WO2015070831A1

WO2015070831A1 - Position measuring device

Info

Publication number: WO2015070831A1
Application number: PCT/DE2013/000676
Authority: WO
Inventors: Werner Bloch; Jürgen Gutekunst
Original assignee: Balluff Gmbh
Priority date: 2013-11-13
Filing date: 2013-11-13
Publication date: 2015-05-21
Also published as: DE112013007594A5

Abstract

The invention proposes a position measuring device (10) having a position sensor (12) which contains a position sensor transmitting/receiving antenna (40), a transmitting unit (44), a power supply (42) and a switching element (14), having an evaluation unit (16) which contains an evaluation unit transmitting/receiving antenna (60) which is used by the evaluation unit (16) to emit an energy signal (30a) from which the power supply (42) of the position sensor (12) obtains the energy for the transmitting unit (44), wherein the evaluation unit (16) also contains a receiving unit (64) and provides an output signal (22), and having an actuation element (20) which is associated with a movable object (18) and actuates the switching element (14) of the position sensor (12) in the case of a predefined position (24) of the object (18) or as of a predefined distance (26) between the object (18) and the position sensor (12), wherein the position sensor (12) emits a data signal (32a) via the position sensor transmitting/receiving antenna (40) when the switching element (14) is actuated, which data signal is received by the evaluation unit transmitting/receiving antenna (60) and is provided by the receiving unit (64), with the output signal (22), as a measure of the position (24) of the object (18) with respect to the position sensor (12) or as a measure of the distance (26) between the object (18) and the position sensor (12).

Description

Description title

Position measuring device

The invention relates to a position measuring device according to the independent claim.

The Applicant offers, for example, under the Applicant's Internet link: http://www.Balluff.com, object detection measuring devices based on different physical principles, such as inductive distance sensors, micropulse transducers, magneto-inductive displacement sensors, magnetically coded path and angle measuring systems and, for example, optoelectronic distance sensors. The measuring devices ultimately determine the position of a moving object with respect to a position sensor or the distance of a moving object from the position sensor.

DE 10 2010 008 495 A1 describes a method for measuring the position of an object, in which a magnet associated with the object is moved along a magnetostrictive waveguide, wherein the magnet causes a first magnetic field component in a region in the waveguide, in which case a current signal is provided with a current pulse which causes a current magnetic field in the waveguide, which has at least one field component in the waveguide, which deviates from the field component caused by the magnet, so that in the specific area of the magnetostrictive

Bestätigungskopiel Due to the field change during the current pulse due to the magnetostrictive effect, a wave is produced by the waveguide. The wave is detected in an evaluation unit, wherein the position of the object is determined from the transit time of the wave in the waveguide. The known procedure is characterized in that the current signal begins with a deliberately predetermined current rise ramp, the time course is set so that no wave is detected, and that following the current rise ramp such a current pulse is provided, the Emergence of a detectable wave leads.

In the patent DE 101 40 930 C1, a tactile sensor system is described with which a pinch protection is realized on bus doors. In the door, a transponder realized as RFID (Radio-Frequency Identification) is provided which constantly transmits a sensor signal to an evaluation unit arranged in the door frame. The energy supply of the arranged in the bus door transponder is obtained from a continuously radiated from the evaluation unit energy signal. In a pinching operation arranged in the door seal switching strip is actuated, which is contacted with two damping coils. The two damping coils influence the

Radiation of the sensor signal as a function of the switching state of

Safety edge. With a closed contact of the safety edge, the sensor signal is greatly attenuated or completely suppressed. The field strength drop or the complete omission of the radiated sensor signal is evaluated by a receiving unit in the evaluation as Einklemmvorgang.

The published patent application DE 10 201 1 1 14 612 A1 discloses a method for

Processing of Kanban orders and an RFI D pallet box became known. For the processing of order processes in the context of an order processing in the small parts delivery between a provider and a customer are filled with small parts container from the supplier to a

Delivered and returned from the customer emptied container. The containers are equipped with readable RFID transponders containing data about the container. Several containers are arranged in a box. The reading process after setting an empty container into the box is triggered by a door or a lid of the box is closed.

The invention has for its object to provide a position measuring device that allows easy installation without much effort.

The object is achieved by the features specified in the independent claim.

Disclosure of the invention

The position measuring device according to the invention has a position sensor which contains a position sensor transmit-receive antenna, a transmitting unit, a power supply and a switching element. The position measuring device according to the invention further comprises an evaluation unit, which contains an evaluation unit transmit-receive antenna, via which the evaluation unit radiates an energy signal, from which the power supply of the position sensor gains the energy for the transmission unit. The evaluation unit also contains a receiving unit which provides an output signal. The position measuring device according to the invention further comprises an actuating element which is associated with a movable object which actuates the switching element of the position sensor at a predetermined position of the object with respect to the position sensor or from a predetermined distance of the object from the position sensor. Only with an actuated switching element does the position sensor emit a data signal via the position sensor transceiver antenna which receives the evaluation unit and the receiving unit as the position of the object in relation to the position sensor or as at least a measure of the distance of the object from the position sensor provides.

The position measuring device according to the invention provides a wireless position sensor, so that a hitherto required complex wiring of the position sensor is eliminated. The advantage is particularly noticeable bar, if numerous position sensors are to be installed in an industrial environment.

Due to the fact that the position sensor of the position-measuring device according to the invention emits the position signal only when the switching element is actuated and does not transmit otherwise, the evaluation unit receives a unique signal which clearly corresponds to a specific position of the mobile object with respect to the position sensor or a distance of the mobile object from the position sensor Position sensor can be assigned.

Advantageous developments and refinements of the position measuring device according to the invention are each objects of the dependent claims.

An advantageous embodiment provides that the switching element is a tactile switch and the moving object associated actuator is a simple mechanical actuator. The object associated with the simple mechanical actuator actuates the tactile switch when striking the object or the mechanical actuator to the tactile switch of the position sensor. This embodiment allows a very inexpensive realization on the one hand the simple mechanical actuator and on the other hand of the tactile switch.

Another embodiment provides that the switching element is a magnetically actuated switch and the actuating element is a magnet. The magnet actuates the magnetically actuated switch from a predetermined distance of the object from the position sensor. With this configuration, non-contact detection of the position of the movable object with respect to the position sensor or the distance of the movable object from the position sensor becomes possible. A development of this embodiment provides that the magnet is realized as a permanent magnet. In this case, the actuating element associated with the moving object does not require its own power supply, which is required in an alternative development of this embodiment, namely when the magnet is realized as an electromagnet.

The magnetically actuated switch is preferably realized as a reed contact.

A further embodiment provides that the switching element is a radiation sensor and the actuating element is a radiation source. The radiation source actuates the radiation receiver from a predetermined distance of the object from the position sensor. The optical implementation can be used in particular in an industrial environment in which the introduction of an additional magnetic field is undesirable.

The radiation sensor is, for example, a photodiode and the radiation source is preferably an LED.

Another possible embodiment provides that the switching element is a temperature sensor and the actuating element is a heat source. The heat source actuates the temperature sensor from a predetermined distance of the object from the position sensor.

A development of this embodiment provides that the switching element is a temperature sensor and the actuator is the ambient temperature itself. The temperature sensor is activated at a predetermined temperature in the area of the object and sends the data signal to the receiver.

The present invention distinguishes between the radiation source and the heat source. Radiation source is understood to mean a radiation source which emits electromagnetic radiation outside the infrared range. Det, for example, a light source that emits light in the visible range or in the ultraviolet range. Heat source, on the other hand, means a radiation source which emits light exclusively in the infrared range.

The embodiments with the electromagnet, the radiation source and / or the heat source, ie an active realization of the actuating element, each with a required power supply, allows a diagnosis of the position measuring device according to the invention in that the actuating element is switched at least within the detectable distance range with a predetermined clock. The clocking of the actuator must lead to a corresponding clocking of the output signal. In the case of a deviation of the predetermined signal clock or a complete signal failure, it must be assumed that there is a defect within the position-measuring device according to the invention, so that a corresponding warning can be given. Thus, the reliability and reliability of the position measuring device according to the invention is increased.

A particularly advantageous embodiment of the position measuring device according to the invention provides that the switching element is arranged in the circuit of the position sensor transmitter-receiver antenna. In this embodiment, the power supply of the position sensor is only possible when the switching element is actuated.

A further development provides that the position signal contains a specific position sensor number and / or a specific position specification. Thus, in addition to the determination of the position or the distance, a specific position sensor and / or a specific position can be clearly identified on the basis of the output signal. Furthermore, status information can be transmitted. Furthermore, it can be provided that the data signal contains status information about the object. In the case of a container as an object, the status information can be, for example, the fill level of a medium in the container.

Further advantageous developments and refinements of the position measuring device according to the invention will become apparent from the following description.

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

Brief description of the figures

FIG. 1 shows schematically a position measuring device according to the invention, FIG. 2 shows a position sensor which is contained in the position measuring device according to the invention,

FIG. 3 shows an evaluation unit which is contained in the position-measuring device according to the invention,

FIG. 4 shows a first embodiment of an actuating element associated with a movable object and a switching element contained in the position sensor,

FIG. 5 shows a second embodiment of the actuating element and of the switching element,

FIG. 6 shows a third embodiment of the actuating element and of the switching element,

Figure 7 shows a fourth embodiment of the actuating element and the switching element and

Figure 8 shows a fifth embodiment of the actuating element and the switching element.

Detailed description of the embodiments FIG. 1 shows a position-measuring device 10 according to the invention which has a position sensor 12, a switching element 14 contained in the position sensor 12, an evaluation unit 16 and an actuating element 20 assigned to a movable object 18.

The evaluation unit 16 provides an output signal 22 which reflects at least one measure of a position 24 of the movable object 18 with respect to the position sensor 12 or at least a measure of the movable object 18 located within a predetermined distance 26 from the position sensor 12.

Between the position sensor 12 and the evaluation unit 16 there is a bidirectional radio-frequency radio link 28 which comprises an energy signal 30a emitted by the evaluation unit 16 in the direction of the position sensor 12 and a data signal 32a emitted by the position sensor 12 in the direction of the evaluation unit 16.

Figure 2 shows a block diagram of the position sensor 12. Those parts which correspond to the parts shown in Figure 1, are designated in Figure 2 each with the same reference numerals. This agreement also applies to the following figures.

The position sensor 12 includes a position sensor transceiver antenna 40, symbolized as a dipole arrangement. As an example in the circuit of the position sensor transceiver antenna 40, the switching element 14 is arranged, which is actuated by the actuating element 20.

The position sensor transceiver antenna 40 is connected to both a power supply 42 and a transmitting unit 44, wherein the connection in the exemplary embodiment shown in Figure 2 only exists when the switching element 14 is actuated. The power supply 42, which is provided with a received power signal 30b, and The transmitting unit 44, which provides a data signal 32b which is emitted by the position sensor transceiver antenna 40 as a data signal 32a, may be referred to as the first transponder. Such a

Transponder is available as RFID (Radio-Frequency Identification) device particularly inexpensive.

The power supply 42 obtains from the received energy signal 30b, which corresponds to the radiated energy signal 30a, a power supply signal 46 which is made available to the transmitting unit 44 and supplies the transmitting unit 44 with electrical energy. The transmission unit 44 is provided with a position sensor number 48 and a position specification 50, which can each be transmitted by the transmission unit 44 as part of the data signal 32a, 32b to the evaluation unit 16.

FIG. 3 shows a block diagram of the evaluation unit 16.

The evaluation unit 16 includes an evaluation unit transceiver antenna 60, a power source 62 and a receiving unit 64, which provides the output signal 22.

The energy source 62 provides an energy signal 30c which emits the evaluation unit transceiver antenna 60, which is also symbolized as a dipole, as the energy signal 30a and which corresponds in the position sensor 12 to the received energy signal 30b. The receiving unit 64 receives the data signal 32b provided by the transmitting unit 44 of the position sensor 12 and data signal 32a radiated by the position sensor transmitting-receiving antenna 40 as a received data signal 32c.

The receiving unit 64 determines the output signal 22 from the received data signal 32c.

The position measuring device 10 according to the invention according to FIGS. 3 works like this:

The data signal 32a emits the position sensor 12 only when the switching element 14 of the position sensor 12 is actuated. The actuation takes place by means of the actuating element 20 associated with the movable object 18. The actuation takes place either at a specific position 24 of the movable object 18 with respect to the position sensor 12 or when the movable object 18 is within the distance 26 from the position sensor 12. The data signal 32a is therefore not emitted when the switching element 14 is not actuated.

The position measuring device 10 according to the invention thereby has a high level of operational reliability. An erroneous emission of the data signal 32a, for example due to interference in the position sensor 12 interference, which would otherwise be possible at any time without the activation by means of the inventively provided switching element 14, is effectively prevented. The actuation of the switching element 14 ensures that the position signal 32a is legitimately emitted.

The power supply of the position sensor 12 via the radiated from the evaluation unit 16 energy signal 30a. The energy source 62 in the evaluation unit 16 constantly provides the energy signal 30c which is emitted by the evaluation unit transceiver antenna 60 at least also in the direction of the position sensor 12 as an energy signal 30a and by the position sensor transceiver antenna 40 as a received energy signal 30b of the power supply 42 in the position sensor 12 is provided.

According to one embodiment, the received energy signal 30b of the power supply 42 is constantly made available, so that the transmitting unit 44 is constantly supplied with energy.

According to a preferred embodiment shown in FIG. 2, it is provided that that the received energy signal 30b of the power supply 42 is provided only when the switching element 14 is actuated. The realization is simply possible because the switching element 14 is arranged in the circuit of the position sensor transceiver antenna 40, so that the reception of the energy signal 30a is possible only when the switching element 14 is actuated.

The output signal 22 may be a simple switching signal signaling that the moving object 18 has reached the determined position 24 with respect to the position sensor 12 or that the object 18 is within the determined distance 26 from the position sensor 12.

The output signal 22 may alternatively or additionally include the position sensor number 48, so that an assignment to a specific position sensor 12 is easily possible.

Furthermore, the output signal 22 may alternatively or additionally include the position indication 50, so that an unambiguous position indication or distance indication is possible.

In addition, the received data signal 32c may include other information, such as status information about the status of the object 18 being monitored by the position sensor 12. For example, reaching a certain level of a medium may be communicated in a container that is at the particular location.

FIG. 4 shows a first exemplary embodiment of the switching element 14 arranged in the position sensor 12 and of the actuating element 20 assigned to the movable object 18. The switching element 14 is realized as a tactile switch 70 which is switched when striking or pressing a simple mechanical actuating element 72. The particular position 24 is when the switch 70 is closed. Only then is the data signal 32a emitted by the position sensor 12. Figure 5 shows a second embodiment of the switching element 14 and the actuating element 20. The switching element 14 is realized as a magnetically actuated switch 80, in the present case as a reed contact, and the actuating element 20 as a magnet 82, in the present case as a permanent magnet. With a sufficiently strong magnetic field 84 closes the magnetically actuated switch 80. The predetermined distance 26 is reached or falls below when the magnetically actuated switch 80 is closed. Only then is the data signal 32a reflecting the specific distance 26 radiated by the position sensor 12.

FIG. 6 shows an exemplary embodiment according to a development of the actuating element 20 shown in FIG. 5 realized as a magnet 82. In the third exemplary embodiment, the permanent magnet is replaced by an electromagnet 90 which requires a power supply 92.

FIG. 7 shows a fourth exemplary embodiment of the switching element 14 and the actuating element 20. The switching element 14 is implemented as a radiation sensor 100 and the actuating element 20 as a radiation source 102. In the present case, the radiation source 102 is an LED and the radiation sensor 100 is a photodiode. The radiation source 102 requires a power supply 104.

Figure 8 shows a fifth embodiment of the switching element 14 and the actuating element 20. The switching element 14 is implemented as a temperature sensor 110 and the actuator 20 as a heat source 1 12. The heat source 102 also requires a power supply 1 14.

In a further embodiment, the switching element 14 is again realized as a temperature sensor 110, but the actuating element is the ambient temperature in the region of the object 18 per se. The temperature sensor 110 is activated from a predetermined temperature. In the exemplary embodiments of both the switching element 14 and the actuating element 20 shown in FIGS. 5, 6, 7 and 8, the switching element 14 is actuated whenever the actuating element 20 or the movable object 18 is at the beginning of the determined distance 26 or is within the predetermined distance 26 from the position sensor 12.

The exemplary embodiments shown in FIGS. 6, 7 and 8 each show an active actuating element 20, which in each case requires a power supply 92, 104, 114. The advantage with these implementations is that a diagnosis of the position measuring device 10 according to the invention can be carried out. By switching the power supply 92, 104, 114 with a predetermined clock and a comparison of the output 22 provided by the evaluation unit 16 with the known clock can be concluded in case of deviations or a complete absence of the clock on a fault in the position measuring device 10 according to the invention. A corresponding warning signal can be provided which prompts an operator of the position-measuring device 10 according to the invention for checking the position-measuring device 10. This further increases the operational safety and reliability of the position-measuring device 10 according to the invention.

Claims

claims

1. Position measuring device (10)

a position sensor (12) including a position sensor transceiver antenna (40), a transmitting unit (44), a power supply (42), and a switching element (14),

with an evaluation unit (16) which contains an evaluation unit transceiver antenna (60), via which the evaluation unit (16) radiates an energy signal (30a), from which the power supply (42) of the position sensor (12) the energy for the transmitting unit (44) wins, wherein the evaluation unit (16) further contains a receiving unit (64) and provides an output signal (22), as well as

with an actuating element (20) which is associated with a movable object (18), which the switching element (16) of the position sensor (12) at a predetermined position (24) of the object (18) with respect to the position sensor (12) or from a predetermined distance (26) of the object (18) from the position sensor (12) is actuated, wherein the position sensor (18) with actuated switching element (14) a data signal (32a) via the position sensor transmitting-receiving antenna (40) radiates the Evaluation unit transmit-receive antenna (60) receives and the receiving unit (64) with the output signal (22) as a measure of the position (26) of the object (18) or as a measure of the distance (26) of the object (18 ) from the position sensor (12).

2. Position measuring device according to claim 1, wherein the switching element (14) is a tactile switch (70) and the object (18) associated with the actuating element (20) is a mechanical actuating element (72).

3. Position measuring device according to claim 1, wherein the switching element (14) is a magnetically operated switch (80) and the actuating element (20) is a magnet (82).

4. Position measuring device according to claim 3, wherein the magnet (82) is a permanent magnet.

5. Position measuring device according to claim 3, wherein the magnet a

Electromagnet (90) is.

6. Position measuring device according to one of claims 3 to 5, wherein the magnetically actuated switch (80) is a reed contact.

7. Position measuring device according to claim 1, wherein the switching element (14) is a radiation sensor (100) and the actuating element (20) is a radiation source (102).

8. Position measuring device according to claim 7, wherein the radiation sensor (100) is a photodiode and the radiation source (102) is an LED.

9. Position measuring device according to claim 1, wherein the switching element (14) is a temperature sensor (110) and the actuating element (20) is a heat source (112).

10. Position measuring device according to claim 9, wherein the heat source is the ambient temperature.

A position measuring apparatus according to any one of claims 5 to 10, wherein clocking of a power supply (92, 104, 114) of the operating member (20) and diagnosis of the position measuring apparatus (10) are provided on the basis of the clocking.

12. Position measuring device according to claim 1, wherein the switching element (14) is arranged in the circuit of the position sensor transceiver antenna (40), so that the power supply (42), the transmitting unit (44) only with actuated switching element (14) with energy.

13. Position measuring device according to claim 1, wherein the data signal (32a) is associated with a predetermined position sensor number (48) contained in the output signal (22).

14. Position measuring device according to claim 1, wherein the data signal (32a) is associated with a position indication (50) contained in the output signal (22).

15. Position measuring device according to claim 1, wherein the data signal (32a) is associated with a status information about the object (18) contained in the output signal (22).

16. Position measuring device according to claim 15, wherein the status information corresponds to a level in a container as object (18).