WO2008126112A1

WO2008126112A1 - Device and method to control operating machines

Info

Publication number: WO2008126112A1
Application number: PCT/IT2007/000271
Authority: WO
Inventors: Gianmarco Bonetti; Alessandro Bertola
Original assignee: C.O.B.O. S.P.A.
Priority date: 2007-04-12
Filing date: 2007-04-12
Publication date: 2008-10-23

Abstract

A controlling device for operating machines comprises an identifier of a tool (3) removably associable to an arm (2) of an operating machine, said identifier comprising a first portion (5) associable to the arm (2) and a second portion (6) associable to the tool (3); wherein the first portion (5) is connected to the second portion (6) by way of electromagnetic waves.

Description

DESCRIPTION DEVICE AND METHOD TO CONTROL OPERATING MACHINES

The present invention relates to a controlling device and method, in particular for operating machines. In particular, the present invention applies to^' the control of safety parameters for the coupling of a swinging arm of an operating machine with a working tool. The operating machines to which the invention advantageously applies are by way of example vehicles moving in a given work area and provided with at least one telescopic arm to handle the tool connected to said arm, said tool typically being interchangeable. Said operating machines can be associated to a plurality of types of interchangeable tools or equipment, such as for instance forks or footboards for people transport. In order to ensure acceptable safety levels also in compliance with specific law regulations, the operation of, the operating machine depends on the type of tool used. In other words, the operating machine should be subject to limitations depending on the coupling of the tool with, the arm and in particular precisely on the type of tool used.

By way of example, such limitations can relate to the feeding speed of the operating machine or to- the exten- sion of the- swinging arm or to the inclination thereof. Known controlling devices include an identifier of the tool consisting of connection systems between the tool and , the arm comprising a series of jumpers or encoded microswitches, or the operator, once the tool is mounted, enters the tool identification data into a controlling computer on board of the machine, which configures the safety parameters associated to the tool. Another limitation relates to the safe connection, between the tool and the arm. As a matter of fact, a safety pin is mounted between arm and tool so as to prevent unwanted rotations or shifts between arm and tool. It is known about devices for controlling the safe insertion of the pin, comprising a sensor checking the exact positioning of the pin. If the latter is not exactly in position, the controlling device prevents the operating machine from moving.

Disadvantageously, known controlling devices for operating machines are not reliable enough and do not ensure acceptable safety levels. First of all, known controlling devices can be misused, thus highly jeopardizing safety conditions. As a matter of fact, the limitations of a certain type of tool can be bypassed by easily tampering with the connection between the latter and the swinging arm of the operating machine and "simulating" the presence of a different tool with lower safety requirements. This possibility can lead to - even serious - accidents jeopardizing operators' safety. Moreover, the traditional configuration of tool identifiers shows the disadvantage of having a limited number of combinations that can be used to identify the various types of -tool applicable to the arm of the operating machine . In other words, given a certain type of connection, only a limited and precise number of tools can be recognized by known devices.

Furthermore, the sensor apt to detect the position of the safety pin is not reliable enough in known devices. As a matter of fact, said sensor, which is generally a proximity detector, has an extremely reduced field of action and the radial clearances of the pin, if present, can give rise to false sensor readings.

The aim of the present invention, therefore, is to propose a controlling device and method for operating machines that is free from the drawbacks mentioned above. In particular, the aim of the present invention is to propose a controlling device and method for operating machines that is characterized by high reliability and safety. Moreover, the aim of the present invention is to- propose a controlling device and method for operating machines in which tool recognition is univocally determined and cannot be illegitimately altered.

Furthermore, the aim of the present invention is to pro- pose a controlling device and method to operate machines in which the position of the safety pin is efficiently and reliably evaluated.

The technical task and the aims referred to above are basically achieved by a controlling device and method to operate machines according to one or more of the appended claims .

Further characteristics and advantages of the present invention will be more apparent from the indicative and therefore nόn-limiting description of a preferred though not exclusive embodiment of a controlling device and method to operate machines, as shown in the accompanying drawings, in which:

- Figure 1 shows a perspective view of the device according to the present invention associated to the arm of an operating machine;

- Figure 2 shows a perspective view of a first portion of the device of Figure 1;

- Figure 3 shows a functional block diagram of a second portion of the device of Figure 1; and - Figure 4 shows an exploded view of a sensor associated to the first portion of the device of Figure 1. Referring to the accompanying figures, the numeral 1 globally refers to a controlling device for operating machines. The device 1 is advantageously applied to an operating machine (not shown) such as for instance a vehicle equipped with a swinging and/or telescopic arm 2 onto which is mounted near a free end 2a thereof (head 2a of the arm .2) a working tool 3 that is interchangeable de- pending on the various needs. Said tool 3 can be by way of example a fork to handle pallets (shown by way of ..example in Figure 1) or a footboard or cage to transport people. The device 1 comprises a_. first portion Ia mounted onto the arm 2 of the machine. In particular, the first portion Ia is mounted near the end 2a of the arm 2 to which the tool 3 is associated. The device 1 further comprises a second portion Ib mounted onto the tool 3. The device 1 comprises an identifier of the tool.3 used. As a matter of fact, in operating machines as described/ it is necessary to recognize the tool that is mounted every time so that the machine can be operated with the limitations required to obtain a suitable safety level. The identifier includes a first portion 5 integrated into the first portion Ia of the device 1 and a second portion 6 integrated into the second portion Ib of the device 1. The first 5 and the second portion 6 of the identifier communicate with each other by way of electromagnetic waves. Preferably, the link is carried out with radio waves (RF) .

The first portion 5 of the identifier comprises a transceiver station 7 sending and receiving radio signals to and from the second portion 6 (Figure 2). The transceiver station 7 includes an antenna 8 for transmitting said radio signals.

The second portion 6 of the identifier includes a transponder 9 comprising its own antenna 10 for receiving and transmitting said radio signals (Figure 3) . During operation, when the tool 3 is moved near the arm 2 of the machine, a link is established between the first 5 and the second portion 6 by way of radio waves in order- to recognize the tool 3. In detail, the transceiver station 7 sends by means of its antenna 8 a guery radio signal that reaches the transponder 9. The transponder 9 can include its own power supplier. Or, as in the case of the described embodiment, the transponder 9 is a passive element, i.e. free of its own power supplier. In this case the energy required is taken from the query signal itself. As a matter of fact, said signal strikes the antenna 10 of the transponder 9 and generates by magnetic induction an electric current supplying the transponder 9 itself.

In practice, since the query signal is an electromagnetic wave, it carries energy that is collected by the antenna 10 of the transponder 9. In other words, the step of sending energy from the first portion 5 to the second portion 6 and the step of sending the query signal from the first portion 5 to the second portion 6 are the same step. The transponder 9 further comprises a permanent memory, connected to the antenna 10, on which information of various type can be written and read. The permanent memory 11 can be by way of example an EEPROM memory. The permanent memory 11 contains in particular an iden- tification code of the tool 3 to which the transponder 9 is applied, said code identifying univocally the tool, such as for instance series number, or identifying the tool class. When the query signal is picked up by the antenna 10 of the transponder 9, the memory 11 is supplied with power and generates a reply signal containing the identification code and sends it by way of said antenna 10 to the transceiver station 7 through radio waves. The reply signal thus generated is picked up by the an- tenna 8 of the transceiver station 7 and is sent to a first microprocessor unit (not shown in the figures and typically contained in the first portion Ia of the device 1) associated to said station 7. The task of said first microprocessor unit is to demodulate the reply signal so as to obtain the identification code of the tool 3 being used.

The device 1 communicates with the rest of the operating machine by way of a known interface (for instance a connector) 12. Preferably, the interface consists of serial connections (for instance of CAN BUS type) . In particular, the interface 12 is apt to interface with the controller of the operating machine (not shown in the figure) so as to enable the communication of the identification of the tool 2 (for instance the serial code or the code identifying tool type or class) from the first microprocessor unit to the controller of the operating machine. Such controller is known and does not require a detailed description. It includes at least one processing unit (or on-board computer) and. a database (not shown in the figure) containing a list of identification codes of removable tools 3 and a list, connected to the list of codes, of sets of safety parameters or limitations to the operation of the machine. The processing unit is configured so as to receive from the device through the connector 12, and in particular from the first microprocessor unit associated to the transceiver station, the identification code of the tool 3, to query the database in order to associate a plurality of functional parameters of the operating machine to . the identification code and to check the operation of the operating machine so as to ensure the compliance with the functional parameters. In other words, the processing unit sets the necessary limitations for the operating machine as a function of the tool '3 or of the class of tool 3 mounted onto the extensible arm 2. Said limitations can relate to the feeding speed of the machine or the extension of the arm 2 and are necessary to ensure a suitable safety level that might be required by law. It should be noted that the set of limitations -as- sociated to a tool class code also depends on the operating machine itself or on the operating status thereof, since the same type of tool can have different limitations on different machines or on the same machine under different operating conditions. Optionally, the processing unit carried out an intermediate step in which it obtains the tool class starting from the tool identification code, possibly with the help of another database of by processing the identification code itself (for instance checking the value of an encoded field within the tool code) . It is also pos- sible that the first microprocessor unit has the task to select the class of the identified tool, for instance by comparing the received identification code with an inside stored database containing the codes of the classes of enabled tools. This solution proves to be particularly useful in the case of non-serial connections between the device 1 and the on-board unit, since on/off outputs can be used for sending to the on-board computer of a code of tool class (for instance for a code of tool class that can take 16 values, 4 on/off parallel connections are to be used) . If the received code does not belong to any tool class, the microprocessor unit sends to the on-board computer the information of unrecognized tool. In order to increase the safety level, the device 1 is preferably equipped with a second processing unit (not shown) assisting the first one so as to grant redundancy to the transponder detection circuit. Also the second processing unit is configured like the first processing unit. It can demodulate the reply signal and obtain the identification code of the tool 3 being used. Furthermore, it can also be provided with the internal database containing the codes of the classes of enabled tools so as to perform the comparison as described above for the first unit. In one embodiment, the second processing unit receives the signal- from the transceiver station 7 parallel to the first unit (i.e. the first signal that is also received by the first unit) . In a second embodiment, the second processing unit receives a second signal containing the tool identification code stored in the transponder from another transceiver station (not shown) . The redundancy of the detection circuit for the identification code is thus extended also to the receiver of the transponder signal.

The two microprocessor units are configured to exchange sensitive information, such as the tool code or the class of tool code. In case of agreement, one of the two units (master unit, e.g.. the first one) sends to the onboard computer the result of the recognition. In case of disagreement, the master unit sends an error signal. As an alternative, both units send their respective results of the recognition to the on-board computer, which checks them for agreement or disagreement. In a preferred embodiment, the transceiver station 7 cyclically sends by way of its antenna 8 the query radio signal. The transponder 9, after receiving the query signal, replies by sending its own identification code, as explained above. The device thus periodically checks the identity of the tool being fitted and enhances ^'to safety level.

In one embodiment, other data are also stored in the transponder (in particular in the permanent memory 11) beyond the identification code, such as for, instance a date representing the expiry date for the use of the tool. For instance such date can be the date of the last servicing or maintenance or the date on which the validity of the last servicing or maintenance expires. In this Case the transponder 9 is provided with writing functions in the memory 11 beyond reading functions. The writing in the memory 11 can be piloted by way of the transceiver station 7 of the device of the present invention or by way of other external means, such as stationary or mobile positions. For instance, when the tool 3 is undergoing a servicing operations, an electronic tool can be connected to the machine processing unit, said electronic .tool being provided with writing authorization in the transponder 9 (e.g. with electronic keys or certificates) . The on-board computer can thus be controlled from the electronic tool so that it writes such additional data into the transponder, by control- ling the first processing unit arid piloting the transceiver station 7. A similar procedure can be used to store modifications or updates of the tool 3 into the transponder. Further limitations to the function of the operating machine can arise from the correct coupling between the arm 2 and the tool 3. More specifically, the tool 3 is connected to the arm 2 in a known manner. Such connec- tiόn, however, is not enough to ensure the safety level enforced by the rules. Therefore, in order to prevent relative rotations or shifts between tool 3 and arm 2, a safety pin 13 is placed therebetween. The controlling device 1 further comprises a sensor 14 for checking the correct positioning of said pin 13 (Figures 1 and 4) .

Said sensor 14 comprises a generator 15 of a magnetic field. In the described embodiment the generator 15 comprises a coil 16 and a supplier 17 (schematically shown in Figure 4) of an electric current (for instance alternate current) in said coil 16. When a current passes through the latter, said magnetic field is generated. The sensor 14 further comprises a winding 18 through which no current passes in absence of magnetic fields. Stated otherwise, the winding 18 is not supplied with an electric current as for the coil 16.

Said winding 18 is arranged near the coil of the generator 15 of the magnetic field. In further detail, the coil 16 and the winding 18 are coaxial to one another. The sensor 14 is associated to the swinging arm 2 on the seat, obtained in said arm, where the pin head is housed and from which it partially projects. In detail, said seat is coaxial to the coil 16 and to the winding 18. Moreover, in the described embodiment, the coil 16 is getting near the arm 2 whereas the winding 18 is getting away from the arm 2. The position of the two coils 16 and 18 can however be reciprocated.

The sensor 14 further comprises a bobbin 19 supporting both the coil 16 and the winding 18. Said bobbin 19, preferably made of plastic, keeps coil 16 and winding 18. coaxial and separate as well as electrically insulated. Bobbin 19, coil 16 and winding 18 are contained inside an envelope 20, the latter comprising a housing 21 and a cover 22 closed by mans of screws 23. During operation, when the safety pin 13 is not fitted into the housing seat and therefore into the sensor 14, the magnetic field generated by the coil 16 does not interact or weakly interacts with the winding 18. When the safety pin 13 is fitted into the arm 2 and into the tool 3, it is pushed until it is fitted into said seat, for instance by getting sequentially into the coils 16 and 18, until it goes beyond the winding 18. The pin 13 thus conducts the variable magnetic field generated by the coil 16 until it interacts with the winding 18 to a sufficient extent to cause on the latter a magnetically induced electric current that can be detected as better described below.

Preferably, the pin 13 is made of ferromagnetic material so that the conduction of the magnetic field_ is as efficient as possible.

The device 1 further comprises a detector 24 (schematically shown in Figure 4) for detecting the current induced in the winding 18. The detector 24 comprises a first detection circuit (not shown in the figures), which generates a first operating signal representing the current induced on the winding 18 by. the magnetic field.

The device 1 further comprises a third microprocessor unit (not shown in the figures) associated to the detector 24 and connected to the first detection circuit to receive and analyze the first operating signal and generating -as a result an acknowledgement or denial signal for the operation of the machine. In detail, when the pin 13 is correctly fitted into its seat, the third microprocessor unit receives a first operating signal representing a correct induced current, for instance the first operating signal represents a value of amount of current above a certain threshold. In this case the third microprocessor unit, for instance after comparing the amount of current with the threshold value, gener ates the acknowledgement signal authorizing the operation of the operating machine.

The variable current (and as a consequence the magnetic field) generated by the supplier 17 is preferably modu- lated (e.g. a pulsed alternate current), even more preferably with a suitable encoding (e.g. a pulsed alternate current, where pulsed follow a pre-established pattern) As a result, the signal of current induced in the winding 18 is demodulated and decoded by the detector 24 so as to be immune from environmental noise and/or from electromagnetic^' interferences outside the magnetic field generated by the coil 16.

Preferably, the third microprocessor unit further pilots the supplier 17 or at least receives the information re- lating to how the current generated by the supplier 17 is modulated. Demodulation and decoding can thus be performed by the third microprocessor unit. Advantageously, the first microprocessor unit and the third microprocessor unit coincide. -Otherwise stated, the first microprocessor unit and the third microprocessor unit constitute one element that analyses both the signals from the identifier 5, 6 and those from the sensor 14. Moreover, the detector 24 comprises a second detection circuit . (not shown in the figures) connected to the coil 18 parallel to the first circuit and generating a second operating signal which also represents the electric current induced on the winding 18.

The first and the second- circuit make up a redundant system so as to ensure a further safety degree and prevent false readings of the sensor. In detail, when the pin 13 is correctly fitted into its seat and the detection circuits generate consistent operating signals, the third microprocessor unit generates the acknowledgement signal authorizing the operation of the operating machine.

In order to extend the redundancy of the circuit detecting the presence of the safety pin and therefore enhance the safety level, the device 1 is preferably eguipped with a fourth processing unit (not shown) assisting the third one so as to grant redundancy to the detection circuit of the safety pin. The fourth processing unit is also configured like the third processing unit. It is configured to receive the second operating signal from the second detection circuit, demodulate it if required, and decide the acknowledgement or denial signal. The third and fourth microprocessor units are configured to exchange sensitive information, such as the acknowledgement or denial signal. In case of agreement, one of the two units (master unit, e.g. the third one) sends to the on-board computer the result of the checking of the correct insertion of the pin. As an alternative, both units send their respective results of the recognition to the on-board computer, which checks them for agreement or disagreement.

Advantageously, the first and the second microprocessor units coincide with the third and the fourth microprocessor units, respectively. In other words, the functions described above for the first and- the third microproces- sor units are performed by one microprocessor which analyzes both the signals from the identifier 5-, 6 and those from the sensor 14. The same applies to the functions of the second and fourth microprocessors. The present invention achieves the aims established and results in important advantages.

First of all, since the recognition of the tool 3 occurs by way of the transponder 9 applied to the tool 3, such recognition is univocally determined and cannot by altered in any way by an operator, since the identifica- tion code of the tool 3 is sent by means of radio waves . to the transceiver station 7 located on the arm 2 and typically remains unknown to the operator. Moreover, the controlling device according to the present invention is highly versatile. As a matter of fact, the memory 11 of the transponder 9 can contain a very large number of identification codes and the device 1 can recognize quite a larger number of tools 3 that can be applied to the arm 2 of the operating machine. Furthermore, since in order to perform the recognition a contact between the portions of the identifier is no longer required, small clearances between arm 2 and tool 3 are admitted without jeopardizing the identification of the latter. Another advantage to be mentioned consists in that the sensor designated for the evaluation of the position of the safety pin has improved features of accuracy and reliability.

As a matter of fact, since the pin 13 is fitted completely into the sensor 14, the magnetic field gets fully linked to the winding 18 so as to generate the induced electric current. Thus, the sensor 14 has a larger field of action and radial clearances which the pin 13 can be subj ect to are irrelevant for determining whether the pin 13 is in its seat or not. It should be noted that the identification of the tool 3 received by the first microprocessor unit can be related synergically to the pin safety information received by the device 14. As a matter of fact, the signal acknowledging the use of the tool 3 can depend on the pin safety signal in a different way according to the spe cific identification code of the tool 3.

* * * * *

Claims

1. A controlling device (1) for an operating machine, the device comprising an identifier of a tool (3) remov- ably associable to an arm (2) of the operating machine, said identifier comprising a first portion (5) associable to said arm (2) and a second portion (6) associable to said tool (3) , said first portion (5) being linkable to said second portion (6) by way of electromagnetic waves in order to obtain an identificati'on of said tool (3), said device further comprising an interface (12) apt to communicate said identification of the tool (3) to a controller of the operating machine.

2. The device according to claim 1, wherein the first portion (5) comprises a transceiver station (7) apt to send and receive signals by way of said electromagnetic waves to and from the second portion (6), respectively, by means of an antenna (8) associated to the transceiver station (7) . .

3. The device according to any of the preceding claims, wherein the second portion (6) comprises a transponder

(9); said transponder (9) comprising a permanent memoxy (11) and an antenna (10) connected to the permanent memory (11) for communicating, with the first portion (5).

4. The device according to claim 3, wherein the perma- nent memory (11) contains at least one identification code of the tool (3) , which is univocally associated to the latter.

5. The device according to claim 4, wherein the antenna (10) of the second portion (6) is apt to emit an electromagnetic wave for communicating the identification code contained in the memory (11) to the transceiver station (7) .

6. The device according to any of the claims 3 to 5, wherein the electromagnetic waves emitted by the first portion (5) and received by the second portion (6) are the only source of energy for the operation of the transponder (9).

7. The device according to any of the preceding claims, further comprising at least one sensor (14) apt to check the correct positioning of a safety pin (13) for coupling the tool (3) to the swinging arm (2) of the operating machine, the sensor (14) comprising a generator (15) of a magnetic field, a winding (18) and a housing seat (30) for the safety pin (13), said magnetic field being apt to generate a suitable induced electric current in said winding (18) when the safety pin (13) is fitted into said seat (30) .

8. The device according to claim 7, wherein the generator (15.) of the magnetic field comprises at least one coil (16) and a supplier (17) of an electric current in said coil (16) .

9. The device according to claim 8, wherein said coil (16) and the winding (18) are coaxial.

10. The device according to any of the claims 7 to 9, wherein said sensor (14) is associable to the arm (2) of the operating machine near a seat housing the pin (13) obtained on said arm (2) ; said seat (30) of said sensor (14) being coaxial to said seat housing the pin (13) .

11. The device according to any of the claims 7 to 10, further comprising at least a detection circuit connected to said winding (18) so as to generate at least one first operating signal when the magnetic field generates the induced electric current in the winding (18) .

12. The device according to claim 11, further compris- ing at least a microprocessor unit connected to said at least one detection circuit so as to analyze said at least first operating- signal and to generate an acknowledgement signal as a function of said first operating signal.

13. A controlling system for an operating machine comprising:

- a device (1) according to any of the preceding claims, and

- said controller operatively connected to said device (I)- by means of said interface (12) , wherein said controller comprises at least a processing unit configured to receive from the device (1) by way of said interface (12) the identification of the tool (3) and to check the function of the operating machine on the basis of said identification.

14. The controlling system according to the preceding claims, wherein said identification of the tool (3) takes place by way of an identification code and wherein said controller further comprise a database containing a list of the identification codes of the tools (3) and a list, connected to said list of identification codes, of related sets of functional parameters of the machine.

15. The controlling system according to the preceding claim, wherein said processing unit is configured to query said database so as to associate a specific set of functional parameters of the operating machine to said identification code and to check the function of the operating machine in order to ensure the compliance with said specific set of functional parameters.

16. An operating machine comprising a swinging arm (2) and a controlling system according to any of the claims 1 to 12, wherein said first portion (5) of the identifier is associated to the arm (2) .

17. An operating machine comprising a swinging arm (2) and a controlling device according to any of the claims 12 to 16, wherein said first portion (5) of the identifier is associated to the arm (2) .

18. A controlling method for an operating machine, comprising the following steps: - coupling a tool (3) to an arm (2) of the operating machine;

- identifying the tool (3) by way of an identifier comprising a first portion (5) associated to the arm (2) and a second portion (6) associated to the tool (3); the step of identifying the tool (3) comprising the step of establishing a connection between the first portion (5) and the second portion (6) of the identifier by way of electromagnetic waves, and

- checking the function of the operating machine on the basis of said identification of the tool (3) .

19. The method according to claim 18, wherein said step of establishing a connection by way of electromagnetic waves comprises the step of sending a query signal from the first portion (5) to the second portion (6) by means of an antenna (8) associated to a transceiver station (7) of the first portion (5) and the step of sending a reply signal from the second portion (6) to the first portion (5) by means of an antenna (10) associated to a transponder (9) of the second portion (6) .

20. The method according to claim 19, wherein said step of sending the reply signal includes the step of sending at least one identification code univocally associated to the tool (3) ; said identification code being stored in a permanent memory (11) associated to the transponder (9).

21. The method according, to claim 20, further comprising the step of associating said identification code to a set of functional parameters of the operating machine and wherein the step of checking the function of the op- erating machine includes the step of checking the- compliance with said functional parameters .

22. The method according to any of the claims 19 to 22, further comprising the step of supplying said second portion (6) of the identifier by sending energy from the first portion (5) to the second portion (6) by way of electromagnetic waves.

23. The method according to any of the claims 18 to 22, further comprising the step -of checking the correct positioning of a safety pin (13) for coupling the tool (3) to the swinging arm (2) of the operating machine; said checking step comprising the following steps:

- creating a variable magnetic field;

- generating at least one first operating signal representing an electric current induced by the magnetic field on a winding (18); and - analyzing said at least one first operating signal so as to generate an acknowledgement signal as a function of the first operating signal.

24. The method according to claim 23, wherein the safety pin (13) fitted inside the winding (18) conducts said magnetic field inside said winding (18) so as to induce on said winding (18) said induced electric current .

25. The method according to claim 22 or 23, wherein said magnetic field is encoded to induce on said winding

(18) said encoded induced electric current.