EP0164302B1 - Conveyor system with movement-controlled conveyor vehicles - Google Patents

Abstract

A computer-controlled conveying system is provided for use in transporting materials between different locations. The system includes a plurality of carriages for receiving and holding the materials and a track along which the carriages move in transporting the materials. Each of the carriages has a unique identifier, which is used by a system controller to monitor and control the movement of the carriage. A number of transfer units, and corresponding transfer unit controllers, are provided along the track. The transfer unit controllers communicate with a system controller and, in conjunction with the transfer units and information received from the system controller, act to provide the desired path for end of the carriages.

Description

The invention relates to a method according to the preamble of claim 1 and a conveyor system for carrying out this method according to the preamble of claim 14.

In relatively large office buildings or hospitals, the task is to transport various types of goods from one place to another with the greatest possible efficiency. Conveyor systems are used for this in a known manner, in which the transport takes place in track-bound trolleys. The trolleys have conveying containers for receiving the material to be conveyed, which is conveyed with the aid of the trolleys from a station (transmitting station) arranged next to a section of the conveying track to another conveying station (receiving station) located next to another section of the conveying track.

Conveyor systems are known in which the movement of trolleys along a main conveyor track is controlled, from which secondary conveyor tracks branch off to individual stations. Each of the trolleys is assigned a destination address, which is queried when the respective trolley moves along the main conveyor track at the branch points of the individual sub-conveyor tracks from the main conveyor track, in order to determine whether the trolley has reached the addressed destination station.

A computer-controlled conveyor system is also known, in which a central main processor is connected to each conveyor car with conveyor containers. The trolleys in turn each hold a microprocessor, which is in a data exchange with the main processor and enables the storage of a destination address assigned to the assigned trolley; In this way, the known conveyor system enables the transport of the goods to be conveyed to their destination to be controlled.

According to a further known system (US-A-3 908 113), each trolley is provided with a bar code for identity identification, which can be read by reading devices arranged over the system. When a trolley is sent, a destination address assigned to the receiving station is transmitted to a central control unit together with the identification number. If the trolley moves into a switch which is assigned a reading unit, the identification number is recorded via the reading unit and a control signal is sent to the switch according to the target address in order to control the trolley according to the assigned target address to the receiving station. However, such a system does not provide sufficient security against queries, because damage or contamination of the bar codes can lead to error detections. Even if a bar code passes the optical reading unit once, there is no sufficient security against interrogation. Finally, complex traffic controls are required in order to rule out error detection when a tram is stopped.

The invention has for its object to provide a method that enables reliable control of the movements of a plurality of trolleys in a conveyor system.

This object is achieved for the method by the features contained in the characterizing part of claim 1. For the conveyor system, the object is achieved by the features contained in the characterizing part of claim 14. Appropriate further training is specified in the subclaims.

Figur 1

ein Funktionsdiagramm eines Auführungsbeispiels der erfindungsgemäßen Förderanlage,

Figur 2

das Datenformat einer Sendeinformation von der Zentralsteuereinheit zu den Weichensteuereinheiten,

Figur 3

eine Ausgangssteuertabelle für eine Weichensteuereinheit,

Figur 4

ein Datenformat für ein Antwortsignal von einer Weichensteuereinheit zu der Zentralsteuereinheit,

Figur 5

ein Schaltbild eines Kennungssignalgebers in einem Förderwagen,

Figur 6

ein Schaltbild einer Empfangseinrichtung einer Weichensteuereinheit,

Fig. 7

ein Schaltbild einer Antriebsteuereinrichtung eines Förderwagens,

Fig. 8

eine Detektor- und Steuereinrichtung einer Weichensteuereinheit,

Fig. 9

den schematischen Aufbau einer Weicheneinrichtung,

Fig. 10

einen schematischen Aufbau der erfindungsgemäßen Förderanlage mit neun Weicheneinrichtungen und sechs Stationen,

Fig. 11

eine Förderwegtabelle, wie sie in einem Speicher der Zentralsteuereinheit der erfindungsgemäßen Förderanlage entsprechend Fig. 10 gespeichert ist, und

Fig. 12A bis 12D

Flußdiagramme von Steuer- und Überwachungsfunktionen der erfindungsgemäßen Förderanlage.

An exemplary embodiment of the invention is described below with reference to the drawing. Show in it

Figure 1

2 shows a functional diagram of an exemplary embodiment of the conveyor system according to the invention,

Figure 2

the data format of a transmission information from the central control unit to the switch control units,

Figure 3

an output control table for a switch control unit,

Figure 4

a data format for a response signal from a switch control unit to the central control unit,

Figure 5

1 shows a circuit diagram of an identification signal transmitter in a tram,

Figure 6

1 shows a circuit diagram of a receiving device of a switch control unit,

Fig. 7

1 shows a circuit diagram of a drive control device of a trolley,

Fig. 8

a detector and control device of a switch control unit,

Fig. 9

the schematic structure of a switch device,

Fig. 10

1 shows a schematic structure of the conveyor system according to the invention with nine switch devices and six stations,

Fig. 11

a conveyor path table, as it is stored in a memory of the central control unit of the conveyor system according to FIG. 10, and

Figures 12A to 12D

Flow charts of control and monitoring functions of the conveyor system according to the invention.

1 shows the functional diagram of the conveyor system according to the invention, in which material to be conveyed is transported in trolleys 10 via conveyor tracks 12 between transmitting and receiving stations. Each of the trolleys 10 has its own identification signal transmitter, which emits an identification signal that differs from those of the other carriages 10. The conveyor tracks 12 comprise a main conveyor track 14, which forms a main section or a loop, along which the trolleys 10 are moved to secondary conveyor tracks 16 which branch off from the main conveyor track 15. Both the main conveyor track 14 and the secondary conveyor tracks 16 each contain detector rails 18 and power supply rails 20. Each individual trolley 10 contains a motor, to which a supply voltage for driving the trolley 10 along the conveyor tracks 12 is supplied via the power supply rails 20. The detector rails 18 serve to detect the identification signal emitted by the respective identifier of the trolley 10 or to detect the presence of a trolley 10 on the respective conveyor track 12. For this purpose, the detector rails 18 can be arranged at predetermined locations along the conveyor tracks 12, so that with their help an approximate determination of the position of the trolleys 10 on the conveyor tracks 12 is possible.

The conveyor system according to the invention also contains a number of switch devices 22 which are arranged at predetermined locations along the conveyor tracks 12. The switch devices 22 generally represent switching devices for the trolleys 10 between the main conveyor track 14 and the secondary conveyor tracks 16. However, the switch devices 22 can also be used to change the direction of the movement of the trolleys 10 along the main conveyor track 14. Each switch device 22 contains control rails 24 and a movable track section 26.

The control rails 24 of the switch devices 22, like the detector rails 18, contain rail sections for detecting the identification signals of the individual trolleys 10 and rail sections for detecting the presence of the trolleys 10. In addition, the control rails 24 include further rail sections for stopping the trolleys 10.

The movable track section 26 is slidably mounted between two positions relative to the main conveyor track 14 and the secondary conveyor tracks 16. In the first position, the movable track section 26 is aligned with the main conveyor track 14 between two connection points of the respective switch device 22. In the second position, the movable track section 26 is aligned with the secondary conveyor tracks 16 between two other connection points of the switch device 22. For control purposes, the connection points of the individual switch devices 22 are each assigned numbers 0 -3 such that the movable track section 26 is in a straight position, if it is aligned with the connection points 0 and 2 and is in the second (odd) position, if it is in line with the connection points 1 and 3.

The conveyor system according to the invention contains a number of transmitting / receiving control units 28, which are assigned to corresponding transmitting and receiving stations for sending and receiving trolleys 10. Each transmitter / receiver control unit 28 is assigned a station address for its identification. Each transmission / reception control unit is usually arranged on a secondary conveyor track. In a preferred embodiment of the conveyor system according to the invention, the stations are used in two ways, namely as turning stations and as transfer stations. A turning station enables the movement of the trolleys 10 in each case on the same secondary conveyor track into and out of the respective station on the same secondary conveyor track 16.

The result of this is that the trolley 10 that last entered the turning station must be the first to leave it. A pass-through station is characterized in that it allows the trolleys 10 to travel only in a single direction along the secondary conveyor track 16, so that a trolley 10 entering the pass-through station first leaves it. Thus, while only one trolley can either be received or sent in a turning station at the same time, a pass-through station makes it possible to receive a trolley 10 at the same time and to send a further trolley. In a preferred embodiment of the conveyor system according to the invention, at least some of the switch devices 22 can be designed as end stations or can be connected to one, but preferably to two, stations for sending and receiving trolleys 10.

The conveyor system according to the invention also contains a number of switch control units 30, of which one unit each has a switch device 22 in connection stands. The switch control units 30 serve to monitor and control the assigned switch devices 22 and their movable track sections 26 and to monitor the control rails 24 in the respective switch devices 22.

A switch device 22 is controlled by the associated switch control unit 30, which moves the movable track section 26 via a motor with a drive device in the switch device 22 until the desired end position of the movable track section 26 is communicated to the switch control unit 30 by limit switches. Furthermore, each turnout device 22 contains a polarity reversal relay 32 controlled by the associated turnout control unit 30, in order to be able to reverse the polarity of the supply voltage on the sections of the power supply rails 20 in the region of the movable track section 26. Activation of the polarity reversal relay 32 causes a carriage 10 located on the movable track section 26 to move in one direction, while if the polarity reversal relay 32 is not actuated, the carriage 10 moves in the opposite direction. To monitor the switch device 22, the associated switch control unit 30 receives input signals via the control rails 24.

Each turnout control unit 30 can be connected to one or two transmit / receive control units 28, which in turn are connected to the station or stations to which the associated turnout device 22 sends or receives tram 10. The turnout control units 30 are each informed of the numbers of the connection points of the turnout devices 22 connected to the respective station via programmable address switches. Likewise, further programmable address switches are used to tell the switch control unit 30 whether a single station serves as a turning station or as a pass-through station.

This information serves to determine the individual control steps for controlling the movement of a trolley 10 between a station and the switch device 22 connected to it.

A central control unit 34, which is connected to each of the switch control units 30, is used for central control of the conveyor system according to the invention. The central control unit 34 contains a program-controlled processor and a memory as well as an input keyboard 36 for inputting data and information to the memory and a display unit 38 for the optical display of the desired information about the movement states of the trolleys 10. The central control unit 34 serves for the delivery of information to the Different switch control units 30, so that even with a large number of different trolleys 10 in the conveyor system, the movement of an individual trolley 10 from a transmitting station to a receiving station is made possible in the shortest possible time.

In order to ensure exact control by the central control unit 34, this is programmed with a large amount of information about the configuration of the conveyor system according to the invention. A corresponding address is thus communicated to the central control unit 34 for each point control unit 30. For each of the associated switch devices 22, the central control unit 34 is given a number of a so-called standard input connection point (SE) and a so-called standard output connection point (SX). The standard input connection point (SE) is generally the connection point of the switch device 22, which is located on the main traffic line of the tram 10 on the main conveyor track 14 and thus defines the starting or rest position of the movable track section 26. The standard output connection point (SX) is the connection point of the switch device 22, which points in the direction of the main traffic flow and on which all trams 10 die Exit switch device 22, unless another connection point is specified as an exit for the trolley 10 by an instruction.

In order to control and monitor the movement of the trolleys 10, the central control unit 34 sends out a transmission information which is transmitted serially to each point control unit 30. The transmission information, the data format of which is shown in FIG. 2, contains several bytes. The first byte contains the address of the switch control device 30 and the associated switch device 22, for which the following bytes are intended. The second byte contains the numbers of the connection points of the turnout device 22 addressed in byte 1, which form the standard input connection points or the standard output connection points. Byte 3 is used by the central control unit 34 to request information from the switch control units 33 and is also used to control certain functions associated therewith. Byte 4 is not used. Byte 5 contains the identification number of one of the trolleys 10 in the conveyor system according to the invention; With this identification number, the central control unit 34 informs the switch control unit 30 addressed in byte 1 about the identification number of the respective trolley 10, the path of which is to be controlled by the associated switch device. With byte 6, the central control unit 30 informs the switch control unit 30 addressed in byte 1 of the number of the connection point of the associated switch device 22, which is to serve as an output for the trolley 10 identified in byte 5 when the trolley leaves the switch device 22 again. Bytes 7 and 8 each serve to transmit status or control information to the switch control unit 30. Two different bytes are provided for this, because each switch control unit 30, as already mentioned above, is connected to two transceiver control units 28 can stand, so that the information in byte 7 of one transmission / reception control unit 28 and the information in byte 8 of the other transmission / reception control unit 28 is to be assigned.

In connection with the transmission of the identification signals or the identification numbers of the trolleys 10 contained in them as information, an output control table 40 is stored in each switch control unit 30 in a memory, as shown in FIG. 3, with one storage location for each trolley 10 in the conveyor system is provided. Each storage location has a length of 8 bits, bits 4 and 5 identifying the connection point of the corresponding switch device 22 which serves as the exit for the relevant trolley 10. For example, the junction 3 serves as the exit for the trolley 10 with the identification number n. As a result, apart from a change by the central control unit 34, the trolley with the number n leaves the relevant switch device 22, whose associated switch control unit 30 has stored the table shown in FIG. 3, at the connection point 3.

Each time the central control unit 34 selects a point control unit 30, the relevant point control unit 30 responds with its own response signal. FIG. 4 shows a data format for such a response signal. The response signal contains 8 bytes, the first byte containing the address of the answering point control unit 30 or the associated point control device 22. Byte 2 contains monitoring information at predetermined times or status information about the switch device 22. Byte 3 provides the central control unit 34 with information about the entry of a trolley 10 into the control area of the switch control unit 30. Byte 4 contains the identification number of a trolley 10, which in the case of detection of a trolley 10 together with byte 3 serves as information for the central control unit 34. Bytes 5 and 6 contain information for sending and / or receiving a trolley 10 in the area of the station, which is controlled by the corresponding switch control unit 30. When sending a trolley 10, byte 6 contains the destination or receiving address of the trolley 10 being sent, while byte 4 contains the identification number of this trolley. For each response signal, byte 4 is used together with either byte 3 or with bytes 5 and 6. Since the switch control unit 30 preferably controls two transmit / receive control units 28, the output signal contains two further bytes 7 and 8 instead of bytes 5 and 6 in order to provide the corresponding information for a second addressed transmit / receive control unit 28.

In the following, it will be described with reference to FIGS. 5 and 6 how the respective trolleys 10 are detected in the conveyor system according to the invention. Each trolley 10 in the conveyor system contains an identification signal transmitter 44 with a programmable address switch 42. The address switch 42 can be used to set a multiple-bit identification number so that, for example, with an 8-bit identification number, a total of 256 trolleys with different identification numbers are used in the conveyor system can find. The programmable address switch 42 is followed on the output side by a parallel / serial data converter 46, which converts the parallel output data of the programmable address switch 42 into serial data. A driver amplifier 48 is connected to the serial output of the parallel / serial data converter 46, the output signal of which has a level of approximately 6 V. This signal is fed to the control rail 24 via a diode 50 as soon as the trolley 10 comes into contact with this control rail 24 via a sliding contact.

As FIG. 6 shows, the control rail 24 is connected to a switch control device 30. As soon as a trolley 10 comes into contact with a control rail 24, the amplified serial output signal is transmitted from the identification signal generator 44 of the trolley 10 via the control rail 24 to a receiving device 52 in the switch control unit 30. The receiving device 52 contains a comparator device 54, 56, 58 with a differential amplifier 54, the inverting input (-) of which is connected to a voltage tap of a voltage divider consisting of two resistors 56 and 58 and is thus at a voltage of approximately 4 V. Since the output signal of the identifier 44 of the trolley 10 has a level of approximately 6 V, the voltage of 4 V at the inverting input (-) of the differential amplifier 54 serves as a threshold voltage. The serial output signal of the identification signal generator 44 is supplied via the control rail 24 to the non-inverting input (+) of the differential amplifier 54 and is amplified therein. In a downstream serial / parallel data converter 60, the amplified serial signal is converted into a parallel signal which corresponds to the identification number of the trolley set with the programmable address switch 42 of the identification signal transmitter 44. The output of the serial / parallel data converter 60 is connected to a data memory 62, which supplies the identification number to the turnout control unit 30 on request. For this purpose, the serial / parallel converter 60 and the data memory 62 are connected on the control side to the switch control unit 30. After reading the identification number of the respective trolley 10, the switch control unit 30 in question is able, by accessing the output control table 40 stored in it (see FIG. 3), to determine the connection point of the corresponding switch device 22 serving as the output for the trolley 10.

In addition to the respective transmission device 44, each trolley 10 contains a drive control device 64 as shown in FIG. 7. The drive control device 64 contains a motor 66 which is electrically connected to the power supply rails 20 via sliding contacts. The power supply rails 20 consist of two adjacent contact rails 68 and 70, each carrying different voltage potentials, so that the motor 66 connected to the two contact rails 68 and 70 drives the trolley 10. The drive control device 64 also contains a switching relay 72 which, in a first switching position, connects the motor 66 to the voltage potential on the contact rail 70, so that a current flows through the current supply rails 20 through the motor 66 and drives the trolley 10. In the second switching position, the switching relay 72 short-circuits the motor connections in order to bring the motor 66 to a standstill and the trolley 10 to stop.

The switching relay 72 is controlled via the control rail 24 by the point control unit 30 connected to it. For this purpose, each point control unit 30 contains a detector and control device 76, which is shown in more detail in FIG. The detector and control device 76 contains a threshold voltage detector 78, 80, 82 with a differential amplifier 78, the non-inverting input (+) of which is connected to the voltage tap of a voltage divider with the resistors 80 and 82. The threshold voltage present at this voltage tap is approximately 22 V. The inverting input (-) of the differential amplifier 78 is connected to the voltage tap of a further voltage divider, which consists of a resistor 84 and the control rail 24. As long as there is no trolley 10 in the area of the conveyor rail 24, the voltage signal at the inverting input (-) of the differential amplifier is 78 approximately 24 V and is therefore greater than the threshold voltage at the non-inverting input (+). As a result, the differential amplifier 78 outputs an output signal with a low level (low). If, on the other hand, there is a trolley 10 in the area of the control rail 24, the internal resistance 86 of the trolley 10 (see FIG. 7) causes the voltage at the inverting input (-) of the differential amplifier 78 in the event that the value of the internal resistance 86 is approximately 8.2 kiloohms and the value of resistor 84 is about 100 kiloohms lowered to about 2 volts. The result of this is that a high signal level (high) is generated at the output of the differential amplifier 78, which indicates the presence of the trolley 10 on the control rail 24.

In addition to the detection of the presence of a trolley 10 by the detector and control device 76 described above, the voltage on the control rail 24 also serves to control the trolley 10 and is supplied to the drive control device 64 of the trolley 10 via a Zener diode 88 (see FIG. 7) . A zener diode 88 is followed by a two-stage arrangement with a first transistor switch 90 and a second transistor switch 92, the second transistor switch 92 being in a current path with the excitation coil 94 of the switching relay 72. During the presence of a trolley 10 in the area of the control rail 24, the voltage on the control rail 24 is approximately 2 V, so that the Zener diode 88, which has a Zener voltage of approximately 12 V, is in a non-conductive state. This has the consequence that the downstream first switching transistor 90 is controlled in a current-blocking state and the second switching transistor 92 in a current-conducting state, so that an excitation current flows through the excitation coil 94 of the switching relay 72 and the switching relay 72 into the first motor 66 the switching rails 68 and 70 connecting switching position is controlled. In this operating state, the trolley 10 is driven by the motor 66.

The detector and control device 76 of the switch control unit 30 shown in FIG. 8 also has a transistor 96 which is connected to the control rail 24 via a resistor 98. In order to bring the trolley 10 to a standstill, the switch control unit 30 generates a stop signal which is fed to the base of the transistor 96 and controls the transistor 96 in a current-conducting state. The resistor 98 acts via the control rail 24 together with the internal resistor 86 of the drive control device 64 of the trolley 10 as a voltage divider which applies a voltage of approximately 19 V to the Zener diode 88 in the drive control device 64 of the trolley 10. Since this voltage exceeds the Zener voltage (approximately 12 V) of the Zener diode 88, the Zener diode 88 is in a current-conducting state, so that the downstream first switching transistor 90 is also controlled in a current-conducting state and the second switching transistor 92 in a current-blocking state. This results in an interruption of the current flow through the excitation coil 94 of the switching relay 72, so that the switching relay 72 falls back into its second switching position, in which the motor connections of the motor 66 are short-circuited and, accordingly, the trolley 10 is at a standstill.

A rectifier bridge circuit 100, which is connected to the contact rails 68 and 70 on the AC side, serves to supply power to the two-stage arrangement with the first switching transistor 90 and the second switching transistor 92 and the excitation coil 94 of the switching relay 72.

In order to achieve a fault-free function of the conveyor system according to the invention, the identification signal transmitters 44 of the various trolleys 10, the drive control devices 64 of the trolleys 10 or the detector and control devices 76 of the switch control units 30 must not influence one another. If at the exit of a Identifier 44 an output signal with a level of about 6 V is present, this signal has no influence on the conductivity of the Zener diode 88 in the drive control device 64, so that no current flows through the excitation winding 94 of the switching relay 72 and the motor 66 to the contact rails 68 and 70 remains switched. If the trolley 10 is stopped due to a stop signal, the diode 50 at the output of the transmitter 44 of the trolley 10 is controlled by the voltage of about 19 V on the control rail 24 in a non-conductive state, so that a possible by the output resistance of the Transmitter 44 causes the voltage at the zener diode 88 to drop below the zener voltage (approximately 12 V). The consequence of this is that the idle number of the trolley 10 cannot be detected while a trolley 10 is stationary in the area of a control rail 24. In the conveyor system according to the invention, however, it is not necessary due to the control to record the identification number of a trolley 10 which is at a standstill.

It should also be noted that when the transistor 96 is activated by a stop signal from the switch control unit 30, the inverting input (-) of the differential amplifier 78 is at a voltage of 19 V, which is in any case lower than the voltage at the non-inverting input (+) of 22 V, so that the threshold voltage detector 78, 80, 82 receives a high level (high) as long as the trolley 10 is at a standstill and in contact with the control rail 24.

FIG. 9 shows an exemplary embodiment of a switch device 22a. The switch device 22a shown has four connection points with the numbers 0 to 3. A trolley 10, which enters the switch device 22a at one of the four connection points 0 to 3, leaves it at one of the three other connection points on the way to its destination. The connection points 0 and 2 are each connected to sections of the main conveyor track 14, sections of a secondary conveyor track 16a and 16b being connected to the connection points 1 and 3. As already described above in the explanation of the construction of the conveyor system according to the invention, one connection point of the switch device 22a is defined as the standard input connection point (SE) and another connection point as the standard output connection point (SX). In the event that z. B. move the tram 10 in the direction from left to right, the junction 0 to the standard entrance junction (SE) and the junction 2 to the standard exit junction (SX) is chosen because these two junction 0 and 2 are in the course of the main traffic line, namely the main conveyor track. The switch device 22a further includes a movable track section 26a, which is positioned between the standard input connection point 0 and the standard output connection point 2. If a trolley 10 moves on one of the branching sections of the secondary conveyor track 16a or 16b, the movable track section 26a is moved into the position shown in broken lines.

Control rails 24a, which consist of a pair of detector rails 105 and a stop rail 104 lying between them, are arranged on the movable track section 26a. The stop rail 104 is used to stop a trolley 10 and to detect its presence. The detector rails 105 detect the presence of a trolley 10 on the movable track section 26a in the event that the trolley 10 is not in the area of the stop rail 104. The control rails 24a thus serve to notify the switch control unit 30 via the detector rail 105 when a trolley has entered the associated switch device 22a, and they also serve to bring the trolley 10 to a stop on the movable track section 26a via the stop rail 104. After the conveyor carriage 10 has stopped, the movable track section 26a can be moved into its second position, shown in broken lines, in order to enable the conveyor carriage 10 to move further on the sections of the secondary conveyor track 16a and 16b.

The sections of the main and secondary conveyor tracks connected to the connection points 0 to 3 of the switch device 22a likewise each have a stop rail 104 and a detector rail 106. The detector rails 106 are used, on the one hand, to detect the presence of a trolley 10 on the relevant conveyor track by the downstream detector and control device 76 of the associated point control unit 30. In addition, the receiving device 52 of the point control unit 30 reads in the identification number of the trolley 10 via the detector rail 106. The stop rail 104, like the corresponding stop rail 104 of the movable track section 26a, serves for detecting the presence and for stopping a trolley 10. Since each conveyor track in the area of the respective connection point 0 to 3 of the switch device 22a has a stop rail 104 and a detector rail 106 it is possible to prevent the transport of a trolley 10 into the switch device 22a as long as a trolley 10 is already in the switch device 22a; the turnout control unit 30 is informed at all times of the presence and the identification numbers of the trolleys 10 ready to enter or leave the turnout device 22a.

In connection with the movement of the trolley 10 from the movable track section 26a to one of the branching sections 16a and 16b of the secondary conveyor track, the polarity reversal relay 32 (cf. FIG. 1) serves to set the desired voltage polarity on the power supply rails 20a of the movable track section 26a such that the trolley 10 can leave the switch device 22a in different directions, namely on the section 16a or on the section 16b.

The exemplary embodiment of the conveyor system shown schematically in FIG. 10 serves to explain the functioning of the conveyor systems according to the invention. In the embodiment shown, six stations A to F are provided for sending and / or receiving trolleys 10; each transmission / reception station A to F is assigned a transmission / reception control unit 28a to 28f. The conveyor system also contains nine switch devices 22a to 22i, each of which is connected to its own switch control unit 30a to 30i for controlling and monitoring the sequence of movements of the trolleys 10.

Some of the switch devices 22 serve different functions. The switch devices 22e and 22i are thus exclusively intended to divert the direction of travel of the trolleys 10 at each end of the main conveyor track 14. The main conveyor track 14 consists of two parallel directional tracks, along which the trolleys 10 travel in opposite directions. Each trolley 10 that enters one of the two switch devices 22e or 22i is transferred from one directional track to the other directional track of the main conveyor track 14 with the aid of the respective movable track section 26e or 26i.

The switch device 22a, 22f and 22g serve u. a. to redirect the trolley 10 to a turning conveyor track 16a, 16d or 16e. On each of the turning conveyor tracks 16a, 16d and 16e, the trolley 10 can be bidirectionally either from the corresponding switch device 22a, 22f or 22g to a turning / receiving station A, D or E or in the opposite direction from one of the transmitting / receiving stations A, Drive D or E to the corresponding switch device 22a, 22f or 22g. This means that the switch device 22a can transport trolley 10 both to the transmitting / receiving station A and can receive from it. Likewise, the switch device 22f serves both for sending trolleys 10 to the transmitting / receiving station D and for receiving the trolleys 10 from this station D. In addition, in the exemplary embodiment of the conveyor system according to the invention shown, station D serves to temporarily park certain trolleys 10. Accordingly the standard exit connection point (SX) of the switch device 22f is assigned to the connection point 2 connected to the station D. As long as no other connection point of the switch device 22f to the standard exit connection point (SX) is selected, all of the trolleys 10 entering the switch device 22f are sent to the station D. This will be explained in more detail later. The turnout device 22g in turn serves to send or receive the trolleys 10 to and from the transmitting / receiving station E via the turning conveyor track 16e.

In addition to the reversing conveyor tracks 16a, 16d and 16e, the conveyor system shown in FIG. 10 also contains secondary conveyor tracks 16b, 16c and 16f, which only allow conveyor car transport in one direction. These secondary conveyor tracks 16b, 16c and 16f serve to convey the trolleys 10 from the respective switch devices 22a, 22d and 22h in one direction to transmitting / receiving stations, so that they receive the trolleys 10 from this one direction Stations that can only forward trams in the same direction. Specifically, the switch device 22a, which, as already described, is connected to the station A via the turning conveyor track 16a, is additionally connected to the transmitting / receiving station B for receiving the trolleys 10 via a section of the secondary conveyor track 16b. The switch device 22d enables the transport of the trolleys 10 to the station C via the secondary conveyor track 16c, and the switch device 22h is connected via a section of the secondary conveyor track 16f to the transmitting / receiving station F, which receives the conveyor cars 10 from the switch device 22h. To transport the trolleys 10 from the stations B, C and F to a respective switch device, the switch devices 22c and 22g are each connected to the stations B and F via sections of the secondary conveyor tracks 16b and 16f, while the switch device 22d both for reception and is also connected to the station C for sending the trolleys 10 via the secondary conveyor track 16c.

In the course of the main conveyor track 14, the switch device 22b is furthermore arranged, which has two simultaneously movable track sections 22b and 22b 'lying parallel to one another. The two movable track sections 22b and 22b 'are slidably mounted between the connection points 0 to 3 of the switch device 22b in such a way that the track section labeled 26b can be moved from a position aligned with the connection points 1 and 3 to a position between the connection points 0 and 2 and the other track section 26b 'is simultaneously shifted from a position between the connection points 0 and 2 into the position shown in broken lines. With the help of this switch device 22b, it is possible to divert a trolley 10 from one directional track of the main conveyor track 14 to the other directional track, so that there is the possibility of the route and the Shorten the travel time of a tram 10 from one station to another station. If, for example, a trolley 10 is dispatched from station A, to which station E is assigned as the destination address, where trolleys 10 entering the movable track section 26b 'between the connection points 1 and 3 of the point device 22b are moved between the connection points 0 and 2, so that the trolley 10 can reach the station E from this position via the switch device 22g. Otherwise, the trolley 10 would have had to pass through switch devices 22c, 22d, 22e and 22f on its way to station E.

With regard to the switch directions 22e and 22i at the ends of the main conveyor track 14, it should be pointed out that it is also possible to guide the direction tracks of the main conveyor track 14 into one another at their ends in a semicircle, so that the two direction tracks of the main conveyor track 14 are one in this way form a closed loop. In this case, the two switch devices 22e and 22i can be omitted. Furthermore, it is also not necessary for the two directional tracks of the main conveyor track 14 to run parallel to one another, as shown in FIG. 10; In accordance with the respective spatial requirements, it may be more advantageous to loop the directional tracks at a large distance from one another.

In the illustrated embodiment of the conveyor system according to the invention, the switch devices 22 serve to connect secondary conveyor tracks to the main conveyor track 14. In addition, within the scope of the invention it is also possible to connect or connect entire conveyor track systems to the main conveyor track 14 with the help of the switch devices 22. With regard to the control and monitoring of the conveyor system according to the invention, there are no restrictions.

In connection with the input of information to the central control unit 34 required for the configuration of the conveyor system according to the invention, a conveyor path table 110 is created in the memory of the central control unit 34. With reference to the exemplary embodiment of the conveyor system according to the invention shown in FIG. 10, such a conveyor path table 110 is shown in FIG. The conveyor path table 110 contains all the transmitting or receiving stations A to F and all the switch devices 22a to 22i of the conveyor system according to FIG. 10, the rows and the switching devices 22a to 22i the columns of the conveyor path table 110 being assigned to the transmitting / receiving stations A to F. In order to store the necessary conveyor path information of a trolley 10 on the way to its destination station, the number of each connection point 0 to 3 serving as the exit for the trolley 10 of the switch devices 22 a to 22 i that the trolley 10 is entered in the line of the respective destination station on the way to the destination station. Only those points 22 with their connection points 0 to 3 serving as an exit for the trolley 10 are entered in the conveyor path table 110, in which a different connection point is intended as an exit for the trolley 10 on its way to the destination station than the respective standard exit connection point (SX ). The conveyor path table 110 arises from the point of view of determining the shortest possible conveyor path for the trolley 10 on the way to its receiving station, including the switch devices 22 with which the trolley 10 comes into contact and whose connection point serving as an exit for the trolley 10 is other than is the respective standard output connector (SX). The content of the conveyor path table 110 is independent of the station from which the conveyor truck 10 was sent.

According to the conveyor path table 110, a trolley 10, to which station B (see FIG. 10) is assigned as the destination address, must instead leave the switch device 22f instead of at the standard exit connection point 2 at the connection point 1, with the corresponding movable track section 26f by the associated switch control device 30f is moved into an aligned position with the connection point 1. If this trolley 10 comes from the right into the area of the switch device 22b, the associated switch control unit 30b will preferably determine the connection point 0 as the output for the trolley 10 and not the standard exit connection point 3. Likewise, the trolley 10 with the station B as the destination address Switch device 22a does not leave the standard exit connection point 2, but instead the trolley 10 is controlled to leave the switch device 22a by means of the movable track section 26a in a position aligned with the connection point 3. In the case of the other switch devices 22 which the trolley 10 traverses on its way to the destination station B, the associated switch control device 30 controls the respective movable track section 26 such that the trolley can leave the respective switch device 22 at its standard exit connection point (SX).

The movement of a trolley 10 from a transmitting station to a receiving station is explained below using an example. It is assumed that station B contains a trolley 10 to be sent to station E. The user of the conveyor system first enters the address of the receiving station E into the transmitting / receiving control unit 28b assigned to the transmitting station B. This address information is received by the switch control device 30a, via which the transceiver control unit 28b is connected to the central control unit 34. Is the receiving station E for the trolley 10th Ready to receive, the central control unit 34 transmits corresponding information to the switch control unit 30a for sending the trolley 10. As soon as the trolley 10 leaves the transmitting station B, its identification number is detected via the detector rail 106 of the secondary conveyor track 16b indicated by a point in FIG. The identification number is transmitted to the central control unit 34 together with the transmission address of the transmission station B via the switch control unit 30a. It is further assumed that the conveyor system shown in FIG. 10 is capable of controlling and monitoring 16 individual trolleys 10 and that the trolley 10 sent to the receiving station E has the identification number 13. The central control unit 34 now accesses the conveyor path table 110 stored in its memory in order to determine the desired conveyor path of the trolley 10 with the identification number 13 to the station E. At the station E as the receiving station, the conveyor path table 110 contains the instruction to assign the trolley 10 in the switch device 22b to the connection point 0 as an output. This instruction is communicated to the switch control unit 30b by the central control unit 34. Correspondingly, the switch control units 30f and 30e receive the instruction from the central control unit 34 based on the conveyor path table 110 to control the associated switch devices 22f and 22g in such a way that the trolley 10 with the identification number 13 leaves the connection points 1 and 2, respectively. The switch control unit 30g thus contains the information that the trolley 10 with the identification number 13 reaches the receiving station E when it leaves the switch device 22g at its junction 2. On its way to the station E, the trolley 10 with the identification number 13 will additionally pass through the switch devices 22c, 22d and 22e, the associated switch control units 30c, 30d and 30e determining the respective standard exit connection point (SX) as the exit for the trolley 10.

In connection with the instructions received from the central control unit 34, the point control units 30b, 30f and 30g store in the output control table 40 (see FIG. 3) stored in their memories in the row for the trolley 10 with the identification number 13 the respective number as the output for the trolley 10 serving connection point of the associated switch devices 22b, 22f and 22g. In the table spaces for the individual trolleys 10, in which no entry of a number of the connection point has been made, a substitute code word is stored instead, which designates the respective standard exit connection point of the relevant switch device 22.

When the trolley 10 with the identification number 13 leaves the transmitting station B, the switch control unit 30a outputs a response signal containing the identification number 13 of the trolley 10 to the central control unit 34. As already shown in FIG. 4, this response signal contains a number of information bytes, of which byte 4 the identification number 13 of the trolley 10, byte 6 the address of the receiving station E and byte 1 the address of the switching device 22a or the one assigned to it and the response signal sending switch control unit 30a contains. If the trolley 10 with the identification number 13 reaches the switch device 22c, the assigned switch control unit 30c accesses the output control table 40 stored in it and takes from it the information that the tram 10 located in the switch device 22c has the standard exit connection point 2 as an exit to the main conveyor track 14 can be assigned. This determination is made by querying the identification bit 6 in the line for the trolley 10 with the identification number 13 of the output control table 40, a value 0 of the identification bit meaning that the standard exit connection point (SX) is provided as the output for the trolley 10. The switch control unit 30c 4 in turn sends a transmission information to the central control unit 34 with the data format shown in FIG. 4, which in bytes 3 and 4 informs the central control unit 34 that the point control unit 30c identified in byte 1 has detected the presence of a trolley 10 with the identification number 13 . Correspondingly, the switch control units 30d and 30e control the switch devices 22d and 22e assigned to them in such a way that the trolley 10 with the identification number 13 leaves both switch devices 22d and 22e via their standard exit connection points 2 and 0, respectively.

In the case of the switch devices 22f and 22b, the associated switch control units 30f and 30b determine from the output control tables 40 stored in them that the tram 10 with the identification number 13 is not the respective standard exit point (SX), but the connection point 1 of the switch device 22f or the connection point 0 the switch device 22b serves as an output. Correspondingly, the switch control units 30f and 30b control the movable track sections 26f and 26b of the switch devices 22f and 22b so that they are aligned with the connection points intended for outputs.

As soon as the trolley 10 with the identification number 13 reaches the switch device 22g, the output control table 40 in the memory of the associated switch control unit 30g for the identification number 13 indicates that the relevant trolley 10 is to be rerouted to the connection point 2. Before the trolley 10 with the identification number 13 enters the switch device 22g, it is identified via the detector rail 106 on the section of the main conveyor track 14 connected to the connection point 3 and the arrival of the trolley 10 is communicated to the central control unit 34. Until then, the central control unit 34 has the entire movement sequence of the trolley 10 with the identification number 13 is monitored with the aid of the transmission information received and given by it in the data formats indicated in FIG. 2 or in FIG. 4. If the transfer of the trolley 10 from the transmitting station B to the receiving station E has ended, the central control unit 34 terminates the execution of the program part currently running in it and gives the instructions to the switch control units 30b, 30f and 30g, in the respective output control tables 40 the to replace the respective exit for the trolley 10 with the identification number 13 by corresponding information values which denote the standard exit connection points (SX) of the respectively assigned switch devices 22b, 22f and 22g.

The control sequence for the movement of two different trolleys 10 to and from a common switch device 22 is described below with the aid of a further example. It is assumed here that the two trolleys 10 have the identification numbers 7 and 12 and move together on the main conveyor track 14 in the direction of the switch device 22a. It is further assumed that the tram 10 with the identification number 7 is assigned the destination address of the station C and that the trolley 10 with the identification number 12 has the destination A as its destination, which is connected to the switch device 22a via the turning conveyor track 16a. Finally, it is assumed that the trolley 10 with the identification number 7 moves in front of the trolley 10 with the identification number 12 on the main conveyor track 14. As soon as the trolley 10 with the identification number 7 arrives in the section of the main conveyor track 14 immediately in front of the connection point 0 of the switch device 22a, the detector and control device 76 in the switch control unit 30a detects the presence of the trolley 10 via the stop rail 104 (see FIG. 9) with the Identification number 7 immediately in front of the connection point 0 and generates a stop signal for the stop rails 104 of those conveyor track sections which are connected to the other connection points of the switch device 22a serving as an input. In the case of the switch device 22a, only the connection point 1 serves as a further input, so that the switch control unit 30a generates a stop signal on the stop rail 104 of the section of the turning conveyor track 16a connected to the connection point 1. Since the switch devices 22 can each accommodate only a single trolley 10, the stop signal on the stop rail 104 prevents further trolleys 10 from entering the switch device 22a as long as the trolley 10 with the identification number 7 is in the switch device 22a. In the case of the switch device 22a, this has the consequence that each trolley 10 which is emitted by the station A is stopped in front of the connection point 1 of the switch device 22a.

As soon as the trolley 7 reaches the subsequent detector rail 106 in front of the connection point 0 of the switch device 22a after driving over the stop rail 104 on the main conveyor track 14, the associated switch control unit 30a also generates a stop signal for the stop rail 104 just passed by the trolley 10 with the identification number 7, so that the subsequent trolley 10 with the identification number 12 is stopped on the stop rail 104 until the trolley 10 with the identification number 7 has left the switch device 22a. As already explained above with reference to the trolley 10 with the identification number 13, the receiving device 52 in the switch control unit 30a reads in the identification number 7 emitted by the transmitting device 44 of the trolley 10 via the detector rail 106. On the basis of the detected identification number 7, the switch control unit 30a determines from the one stored in it Output control table 40 that connection point which is intended as an output for the tram 10 with the identification number 7. In this case, since the trolley 10 with the identification number 7 is assigned the station C as the destination address, the standard exit connection point (SX) of the switch device 22a serves as an exit. This information results from the identification bit 6 in the output control table 40, which indicates with a 0 as an information value that the corresponding trolley 10 is assigned the standard exit connection point (SX) as an exit for leaving the switch device 22a. Since the movable track section 26a of the switch device 22a is in its rest position between the connection points 0 and 2, the trolley 10 with the identification number 7 passes through the switch device 22a without stopping and leaves it at the connection point 2 on the way to its destination station C.

The switch control unit 30a detects, via the detector rail 106 of the section of the main conveyor track 14 connected to the connection point 2 of the switch device 22a, the time at which the trolley 10 with the identification number 7 has left the switch device 22a and thereby recognizes the control of the trolley 10 with the identification number 7 in the area of the switch device 22a as finished. The switch control unit 30a then interrogates the stop rails 104 of the conveyor track sections connected to the connection points serving as inputs for the presence of further trolleys 10. In the example dealt with here, the switch control unit 30a detects the presence of the further conveyor carriage 10 with the identification number 12 on the stop rail 104 of the section of the main conveyor track 14 which is connected to the connection point 0. The switch control unit 30a now cancels the stop signal lying on the stop rail 104, so that the trolley 10 with the Identification number 12 continues its journey via junction 0 to the movable track section 26a of the switch device 22a. The trolley 10 with the identification number 12 passes over the detector rail 106 upstream of the junction 0 on the main conveyor track 14, the switch control unit 30a - as already described above for the trolley 10 with the identification number 7 - the stop rail 104 located in front of the detector rail 106 with a The stop signal is applied and the identification number 12 of the relevant trolley 10 is read in via the detector rail 106. On the basis of the detected identification number 12, the point control unit 30a determines from the output control table 40 stored in it the connection point which is intended as the output for the trolley 10 with the identification number 12. Since the trolley 10 with the identification number 12 is assigned the station A as the destination address, in the example described here, the junction 1 serves as an exit for the trolley 10. It is therefore necessary to move the trolley 10 to the junction 1 using the movable track section 26a to postpone. As soon as the trolley 10 entering the switch device 22a with the identification number 12 reaches the stop rail 104 on the movable track section 26a, the presence of the trolley 10 is detected by the switch control unit 30a and a stop signal for stopping the trolley 10 is emitted. The switch control unit 30a then controls the movable track section 26a from the position aligned with the connection points 0 and 2 into a new position aligned with the connection points 1 and 3 and shown here in broken lines. As soon as the movable track section 26a is in this new position, the switch control unit 30a, by actuating the polarity reversal relay 32, reverses the polarity of the supply voltage on the power supply rails 20a of the movable track section 26a, so that after the stop signal on the stop rail 104 has been removed, the trolley 10 with the identification number 12 the switch device 22a leaves at its junction 1. The trolley 10 travels over the detector rail 105 of the movable track section 26a and subsequently over the detector rail 106 and the stop rail 104 of the section of the turning conveyor track 16a connected to the connection point 1. The switch control unit 30a detects via the stop rail 104 the time at which the trolley 10 with the identification number 12 leaves the switch device 22a and thereby recognizes the control of the trolley 10 with the identification number 12 in the area of the switch device 22a as finished. Thereafter, the switch control unit 30a controls the movable track section 26a back to its rest position between the connection points 0 and 2 and ends the activation of the polarity reversal relay 32, so that the direction of travel for the trolleys 10 on the movable track section 26a again runs from left to right in the direction of the default exit port (SX) of the switch 22a is set. The turnout control unit 30a then again interrogates the stop rails 104 of the conveyor track sections connected to the connection points serving as inputs for the presence of further conveyor carriages 10, in order to control them one after the other as described above by the turnout device 22a.

If the user of the conveyor system according to the invention wishes to send another conveyor truck 10 from station A after the presence of the conveyor truck 10 with the identification number 12 has been determined by the switch control unit 30a, the central control unit 34 provides the evaluation of the by the transmission / reception control unit 28a Transmission information transmitted to the central control unit 32 via the switch control unit 30a (see FIG. 4) for so long until the central control unit 32 has determined that the trolley 10 ready for dispatch in station A is determined next in the sequence of the trolleys 10 to be controlled by the switch device 22a.

Another control function of the central control unit 34 serves to prevent the sending of additional trolleys 10 into the conveyor system if the central control unit 34 has been informed by the user of a maximum permissible number of trolleys 10 rotating in the conveyor system. In this case, the central control unit 34 rejects all transmission information sent by the transmission / reception control units 28, which contains a request to send trolleys 10.

In addition to controlling the travel of the individual trolleys 10 through the conveyor system according to the invention, the central control unit 34 is equipped with a large number of further monitoring functions. A first monitoring function relates to the detection of the average time that a trolley 10 needs to travel from one switch device 22 to another switch device 22. In order to determine whether a trolley 10 is moving properly along the main conveyor track 14 to its destination address, the central control unit 34 determines whether a trolley 10 requires an above-average travel time between two switch devices 22. For this purpose, the central control unit 34 stores information about the travel sequences of the individual trolleys 10 in its memory. This information includes, in particular, the address of the sending and receiving stations assigned to the respective trolley 10, the identification numbers of the individual trolleys 10 and the elapsed travel time of the trolley 10. In order to record the travel time of the trolley 10 between two switch devices 22, the central control unit 34 contains for each Trams 10 each have a counter is reset each time the trolley 10 leaves a switch device 22. The detection of the moment at which a trolley 10 leaves a switch device 22 has already been described in detail above. The central control unit 34 constantly compares the counter reading of each individual counter with a predetermined time value. If the counter reading exceeds the specified time value, the central control unit 34 issues an error message together with the identification number of the respective trolley 10 for the user of the conveyor system. The predefined time value is preferably selected to be somewhat longer than the time period which a trolley 10 requires on its way between the most distant switch devices 22 or the detector rails 18 or the control rails 24.

An extension of the monitoring function of the central control unit 34 described above relates to the determination of the approximate position of the respective trolley 10 in the conveyor system at the point in time at which the counter reading the predetermined time value in connection with the detection of the travel time of the trolley 10 between two switch devices 22 described above exceeds. This is done in that the central control unit 34 additionally stores the address of the last switch device 22 that the trolley 10 passed through before the error message occurred. On the basis of this additional information, the user of the conveyor system is able to find the relevant conveyor 10 in the conveyor system in the event of a fault.

According to a second monitoring function of the central control unit 34, the dwell time of each individual trolley 10 in the conveyor system is recorded from a transmission station from the time of its dispatch. For this purpose, the central control unit 34 contains for everyone to be monitored Trams 10 each have a further counter, which is reset as soon as the trolley 10 in question leaves the transmitting station. If the dwell time of the trolley 10 in the conveyor system reaches a predetermined maximum duration, then the central control unit 34 causes a further error message to be issued. The predefined maximum duration is chosen to be slightly longer than the maximum expected time that a trolley 10 needs on its way from a transmitting station to a receiving station when the conveyor system is functioning properly.

This second monitoring function is used to record possible errors that would otherwise go undetected. To explain this fact, reference is made below to the example already described above, in which a trolley 10 with the identification number 13 is sent from station B to station E. It is assumed that, for some reason of error, the soft device 22g does not assign the trolley 10 the connection point 2, but the standard exit connection point 0 as the output. In this case, the trolley 10 with the identification number 13 would constantly circulate on the main conveyor track 14 through the switch devices 22a, 22b, 22g, 22h and 22i, and at each of these switch devices the position of the trolley 10 would be detected by the central control unit 34. In this fault case, after some time the duration of the trolley 10 with the identification number 13 in the conveyor system exceeds the predetermined maximum duration, so that the central control unit issues an error message together with the identification number 13 for the user of the conveyor system.

In connection with this monitoring function, the central control unit 34 advantageously contains a program part which causes the trolley 10 to be controlled back into its transmitting station. The return of the respective trolley 10 can be carried out very easily because the central control unit 34 contains in its memory the addresses of the transmitting stations from which the individual trolleys 10 have been sent to the conveyor system. In a modification of this, it is possible not to send the relevant trolleys 10 back to their respective transmitting stations, but instead to assign the addresses of the storage station D as the destination address to the trolleys 10.

A third monitoring function of the central control unit 34 relates to the recording of the total length of stay of all trolleys 10 in the conveyor system. The total time of stay corresponds to the sum of all times of stay of the individual trolleys 10. With this monitoring function, the user of the conveyor system receives all the necessary information about the degree of utilization of the conveyor system according to the invention.

According to the invention, a further monitoring function of the central control unit 34 relates to the control of trolleys 10 in the event that the receiving station assigned to them in each case via the destination address is overcrowded with other trolleys 10 and is therefore no longer ready to receive. To detect the overloading of a station, each station is assigned a rail, which is connected to the switch control unit 30 associated with the station. If a trolley 10 is located on such a rail, this indicates to the respective switch control unit 30 that the station in question can no longer accommodate any further trolleys 10. In this case, the station in question blocks the access of further trolleys 10 and redirects them. The trams 10 thus redirected continue their journey and, if necessary, reach their desired destination address. The central control unit 34 receives the number of trolleys 10 diverted at the overcrowded station via the respective switch control unit 30 Central control unit 34 compares the current number of redirected trolleys 10 with a predetermined numerical value, and if this numerical value is exceeded, central control unit 34 can, for example, arrange for further trolleys 10 to be sent back to their respective transmitting station on the way to the overcrowded station.

According to the invention, the central control unit 34 carries out an additional monitoring function which serves to provide a predetermined number of trolleys 10 in each station of the conveyor system. For this purpose, the central control unit compares the number of trolleys currently in a station with the predetermined minimum number of trolleys 10 in each station. If the current number of trolleys 10 in the station is less than the predetermined number, the central control unit 34 automatically sends a corresponding number of further trolleys 10 to the station. For this purpose, the conveyor system according to the invention can have a storage station from which the trolleys 10 required to fill up the other stations can be called up.

In addition to the control and monitoring functions described above, the central control unit 34 of the conveyor system according to the invention provides for the display of important information relating to the individual trolleys 10 controlled in the conveyor system travel via a display unit 38 (cf. FIG. 1). The input keyboard 36 allows the user to select the information to be displayed. This information includes the display of all the trolleys 10 that are in motion with their respective identification numbers and their respective sending and receiving stations. Further information of this type relates to the display of the travel times of the individual trolleys 10, the indicators of the current location of the individual trolleys 10 and the display of the respective operating states of the individual stations and switch devices 22. The information about the operating states includes e.g. B. the display of whether a turning point to the central control unit 34 to send a tram 10, or whether the entry and exit of the tram 10 via the corresponding standard input connection points (SE) or standard output connection points (SX) of the switch devices 22.

FIGS. 12A to 12D show flow diagrams of the control and monitoring functions of the central control unit 34 described above.

The invention relates to a computer-controlled conveyor system with a number of trolleys for conveying various types of conveyed goods from transmitting stations to receiving stations. The conveyor system according to the invention has a main conveyor track, along which the trolleys are moved between individual stations. Secondary conveyor tracks branch off from the main conveyor track, on which the trolleys are transported between the main conveyor track and sending or receiving stations.

Sectional switch devices are provided along the main conveyor track. Each switch device has four connection points and a movable track section. The four connection points form connection points for sections of the main conveyor track and / or the secondary conveyor track, with which the movable track section can be brought into an aligned position. The movable track section serves as a link between the main conveyor track and a secondary conveyor track. For this purpose, the movable track section can be moved into two positions, wherein it forms part of the main conveyor track in the first position and forms part of the secondary conveyor track in the second position.

Each turnout device is connected to a turnout control unit. The individual turnout control units are in turn connected to a central control unit which carries out control and monitoring functions in accordance with the invention. Transmit / receive control units, which are assigned to the respective secondary conveyor tracks and are arranged at the various transmit and receive stations, are connected to the central control unit via the individual switch control units. Each trolley is assigned its own identification signal transmitter for controlling and monitoring the movement of the large number of trolleys by the central control unit.

The user of the conveyor system according to the invention enters into the central control unit a receiving address for the transmitting / receiving station to which a conveyor car is to be sent via the main conveyor track. With these two pieces of information, namely the receiving address (or destination address) and the trolley identifier, the central control unit is able to control the movement of the trolley along a desired conveyor track. As soon as the trolley reaches a point device on its way, the associated point control unit uses the information received from the central control unit and spoken by the point control unit to assign the movable track section of the point device to the desired position, so that the trolley can find its way along the desired or selected conveyor track can continue. For this purpose, the point control unit determines the tram identifier and uses it to determine the desired position of the movable one Track section. When the trolley finally reaches a switch device on which the secondary conveyor track connected to the receiving station branches off, the switch control unit controls the movable track section into a position in which the trolley is moved onto the secondary conveyor track and can reach the receiving station addressed by the receiving address.

In addition to the function of controlling the movement of the trolleys from the transmitting stations to the receiving stations with the aid of the trolley identifier, the central control unit with the associated switch control units provides a large number of other additional functions which are important for the function of the conveyor system according to the invention. The central control unit also serves to prevent trolleys from being sent from a transmitting station if the addressed receiving station is not available. The central control unit also automatically changes the specified route during the movement of a trolley if the receiving station is not ready to receive. The central control unit also serves to monitor the approximate position of each individual trolley during its movement along the conveyor track. There is also the possibility of recording the elapsed time of a trolley moving in the conveyor system according to the invention since it was sent from a transmitting station. The duration of use of each individual trolley in the conveyor system according to the invention can be determined accordingly. Another control function of the central control unit is to provide a sufficient number of trolleys for each individual station. In addition, empty trolleys or trolleys, the identification of which cannot be determined, are controlled by the central control unit at specified stations.

From the above description of the conveyor system according to the invention, there are many advantages. Thus, the computer-controlled conveyor system according to the invention enables efficient transportation of each of many trolleys to the desired destination. As a result of the use of identifiers on the trolleys, it is possible to control the movement of each individual trolley on the basis of its trolley identification. The identifier can thus be attached to the trolley with little effort and can easily replace actuators for controlling the movement of the trolley. In addition, the conveyor system according to the invention enables a display and monitoring of the movement of the various trolleys with different target directions, so that the user of the conveyor system is informed about the targets of the various trolleys, their current position and their conveyance in the conveyor system.

Claims (25)

1. Method for controlling the movement of guided conveyor vehicles (10) in a conveyor system from sending stations to receiving stations by way of switch means (22) along conveyor tracks (12), during which, when a conveyor vehicle (10) is transmitted from a sending station to a receiving station, a destination address associated to the receiving station is transmitted, together with a code number associated to the conveyor vehicle (10), from a sending/receiving control unit (28) associated to the sending station to a central control unit (34),
   and during which that address is, at each admission of a conveyor vehicle (10) running along a conveyor track (12), identified by receiving a code signal transmitted by the vehicle and corresponding to its code number, in a switch control unit (30) controlling the respective switch means (22) and being in connection with the central control unit,
   and during which the switch means (22) is controlled by the associated switch control unit (30) as a function of the code number corresponding to the received code signal and of the associated destination address for forwarding in the direction of the receiving station the conveyor vehicle (10) arriving in the switch means (22),
   characterized in
   that, each time, the code signal of a conveyor vehicle (20) is detected by means of an electrical contact and transmitted serially by a detector rail (105,106) associated to the switch means (22), as soon as that rail is passed by a conveyor vehicle (10).
2. Method according to claim 1, characterized in that the route of the conveyor vehicles (10) through the switch means (22) is determined, each time, as a function of the destination addresses of the receiving stations by means of a conveying route list (110) stored in the central control unit (34).
3. Method according to claim 1 or 2, characterized in that ends of the conveyor tracks (12) connected with places of attachment (PORT) of each switch means (22) are observed regarding the appearance of a code signal transmitted by a conveyor vehicle (10) and that detected code signals are received by the switch control unit (50) and transmitted to the central control unit (34).
4. Method according to claims 2 and 3, characterized in that, by means of the central control unit (34) and according to an output control list (40) stored in each switch control unit (30), a coordination is effected between each code number of a conveyor vehicle (10) and the number of the place of attachment (PORT) of the respective switch means (22) serving as output for the conveyor vehicle (10) having the respective code number
5. Method according to one of the preceding claims, characterized in that in each switch means (22) there is received the code signal of a conveyor vehicle (10) located in the switch means, on a track portion (26) travelling between two places of attachment (PORT).
6. Method according to one of the claims 3 to 5, characterized in that, on the ends of the conveyor tracks (12) connected with the places of attachment (PORT) of a switch means (22), the presence of conveyor vehicles (10) is detected by means of stop rails (104) having a greater distance to the corresponding place of attachment (PORT) than the detector rails (106).
7. Method according to claim 6, characterized in that conveyor vehicles (10) arrived on the stop rails (104) are stopped by the switch control unit (30), by sending a stop signal to the stop rails (104), as long as a conveyor vehicle (10) is in the switch means (22).
8. Method according to one of the preceding claims, characterized in that, together with the code number of every single conveyor vehicle, the address of the sending station transmitting the vehicle is stored in a storage of the central control unit (34) and that the destination address of a conveyor vehicle (10) is replaced by the address of the corresponding sending station so that the conveyor vehicle (10) can be sent back, if necessary, to the sending station.
9. Method according to one of the preceding claims, characterized in that a conveyor vehicle (10) to be transmitted from a sending station is prevented from leaving the sending station by sending a stop signal to a stop rail located at the exit of the sending station, if the receiving station addressed by the destination address is not ready for reception.
10. Method according to one of the claims 1 to 8, characterized in that the destination address associated to a conveyor vehicle (10) to be transmitted is replaced by the address of a storage station, if the receiving station determined by the destination address is not ready for reception, and that the conveyor vehicle (10) is moved to the storage station.
11. Method according to one of the preceding claims characterized in that the time required by a conveyor vehicle (10) for running from one switch means (22) to another switch means (22) is registered by the central control unit and that an error message is effected by the central control unit (34) if the registered time exceeds a given time value.
12. Method according to one of the preceding claims, characterized in that the period of dwell of every single conveyor vehicle (10) in the conveyor system is registered by means of the central control unit from the moment of the sending of the vehicle from a sending station and that an error message is effected by the central control unit (34) if the period of dwell exceeds a given maximum period.
13. Method according to one of the preceding claims, characterized in that the momentary number of the conveyor vehicles (10) present in the receiving stations is, each time, registered by the central control unit (34) and that the sending of a conveyor vehicle (10) from a sending station to a receiving station is prevented if the number of the conveyor vehicles (10) present in the receiving station exceeds a given value.
14. Conveyor system for realizing a method according to claim 1 having guided conveyor vehicles (10) whose movement from sending stations to receiving stations by way of switch means (22) along conveyor tracks (12) is controllable,
    in which every sending station is connected, via a sending/ receiving control unit (28) associated to that station, with a central control unit (34) for transmitting a destination address, which is associated to the receiving station, for a conveyor vehicle (10) to be transmitted, in which a switch control unit (30) is associated to every switch means (22) for controlling it,
    characterized in
    that every conveyor vehicle (10) contains a code signal transmitter (44) for the serial transmitting of a code signal, that in the area of every switch means (22) there are located receiving elements (24) for receiving the code signal of a conveyor vehicle (10) present in said area, that the receiving elements (24) are detector rails (105,106) located in the area of the switch means (11) in the course of the conveyor tracks (12) and that in every conveyor vehicle (10) a sliding contact is connected to the exit side of the code signal transmitter (44) in such a way that it gets into contact with the detector rail (105,106) when passing it and that the receiving elements (24) are, with the corresponding switch control unit (30), connected with the central control unit (34) for controlling the movement of the conveyor vehicles (10).
15. Conveyor system according to claim 14, characterized in that every end of the conveyor tracks (12) connected to a place of attachment (PORT) of a switch means (22) has a detector rail (106).
16. Conveyor system according to claim 14 or 15, characterized in that every switch means (22) has a track portion (26) travelling between two positions, said track portion being, in every position, in alignment with two places of attachment of the switch means (22) and that the travelling track portion (26) also has a detector rail (105).
17. Conveyor system according to one of the claims 14 to 16, characterized in that the code signal transmitter (44) in every conveyor vehicle (10) contains an address switch (42) connected to the exit of the code signal transmitter (44) via a parallel/ serial data converter (46).
18. Conveyor system according to claim 17, characterized in that every switch control unit (22) contains a receiving means (52) having a comparator (54,56,58), the entrance side of which is connected to the detector rails, and at the exit side of which a serial/ parallel data converter (60) is inserted.
19. Conveyor system according to one of the claims 14 to 19, characterized in that every detector rail (105,106) is a component part of a control rail (24) with an additional stop rail (104), that the stop rail (104) is stationarily connected with a detector- and control means (76) of the switch control unit (22) and that the stop rail can be loaded by said means with a stop signal (STOP), that every conveyor vehicle (10) has a further sliding contact and that the further sliding contact is connected with a driving control means (64) for stopping and starting the movement of the conveyor vehicle (10).
20. Conveyor system according to claim 19, characterized in that on the ends of the conveyor tracks (12) connected to the places of attachment (PORT) of a switch means (22), the detector rail (106) is connected closer at the corresponding place of attachment (PORT) than the corresponding stop rail (104).
21. Conveyor system according to claim 19 or 20, characterized in that the detector- and control means (76) of every switch control unit (22) contains a threshold voltage detector (78,82,84) whose entrance side is connected to the stop rails (104) and whose exit transmits a detector signal (DETECT) if a conveyor vehicle (10) is present on the corresponding stop rail (104).
22. Conveyor system according to claim 21 characterized in that the driving means (64) has, in every conveyor vehicle (10), an internal resistance (86) connected to the further sliding contact and that the detector- and control means (76) has, in every switch control means (22), a resistance (84) connected with the corresponding stop rails (104) in such a way that, when the further sliding contact contacts the corresponding stop rail (104), the internal resistance (86) of the driving means (64) and the resistance (80) of the detector- and control means (76) form a voltage divider, to the voltage tap of which the entrance of the threshold voltage detector (78,82,84) is connected.
23. Conveyor system according to one of the claims 14 to 22, characterized in that every switch control means (22) contains an electronic storage connected with the central control unit (34), for storing information for controlling the associated switch means (22) as a function of the code number of the corresponding conveyor vehicle (10).
24. Conveyor system according to claim 23, characterized in that the central control unit (34) contains a storage for storing a conveying route list (11) having given conveying routes for several receiving stations.
25. Conveyor system according to one of the claims 14 to 24, characterized in that the central control unit (34) has a display unit (38) for monitoring the movement of the conveyor vehicles (10) in the conveyor system.

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