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Timestamp: 2019-10-17 11:16:20
Document Index: 282948114

Matched Legal Cases: ['art 11', 'art 11', 'art 11', 'art 11', 'art 11', 'art 1', 'art 1', 'art 1', 'art 2', 'art 1', 'art 1', 'art 1', 'art 1', 'art 1']

Position monitoring device - K.A. Schmersal Holding KG
United States Patent 7520426
Hoepken, Hermann (Sprockhovel, DE)
Stratmann, Christoph (Essen, DE)
11/221330
K.A. Schmersal Holding KG (Wuppertal, DE)
235/435, 235/449, 340/539.23
340/539.23, 235/449, 235/382, 235/436, 235/439, 235/382.5, 235/435
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20060220846 Switch acting in a contactless fashion 2006-10-05 Stratmann 340/545.2
DE19928641C1 2001-05-03
DE10230564A1 2004-01-29
DE10348884A1 2005-05-25
GB1452132A 1976-10-13
GB2354557A 2001-03-28
JP63014541 January, 1989 DATA COMMUNICATION SYSTEM
JP11191666 January, 2001 PRINTED CIRCUIT BOARD
WO2003052455A1 2003-06-26 COMMUNICATION SYSTEM COMPRISING A FIRST AND SECOND TRANSCEIVER AND METHOD FOR THE OPERATION THEREOF
JPS6314541A 1988-01-21
JPH11191666A 1999-07-13
1. A position monitoring device for establishing the position of a first part with respect to a second part, the position monitoring device comprising: a transceiver being provided at the first part, a transponder being provided at the second part, the transceiver for emitting an interrogation signal and for receiving a response signal that can be emitted in reaction to the interrogation signal by the transponder, a screen which is adapted to attenuate signals between the transponder and the transceiver corresponding to the relative position of the transceiver at the first part, the transponder at the second part and the screen, wherein two members of the group consisting of the transceiver, the second part and the first part are movable relative to one another, and wherein via the screen a limiting distance between the first and second part is adjustable.
16. The device according to claim 13, wherein two transponders being detectable in a middle position by a transceiver and being transportable by the second part in a position shifted to one or other side of the middle position in which shifted positions one of the two transponders is screened by a screen against the transceiver.
The interrogation signals are received by a coil 10a coupled to a transponder IC 10b, for instance a bar-type coil, in the transponder 3. The received energy expediently supplies the operating energy for the transponder 3, which, however, may also be supplied with power via the bus 7, a separate terminal, a battery or the like. In reaction to the interrogation signals, the transponder 3 emits response signals expediently via the same coil 10a or, if appropriate, a further coil. In the simplest case, said response signals may have a specific frequency or be marked in some other way, in particular contain information bits, e.g a unique transponder identifier. The response signals may additionally depend on the received information bits; by way of example, a key may be stored in the transponder 3, by means of which key received information bits are encrypted and subsequently sent back.
The closed position limiting distance is set by means of the screen 4, which can be adjusted, in particular in a continuously variable manner, between positions having different degrees of attenuation of the signals that propagate between the transceiver 5 and the transponder 3 and which can be fixed, in particular fixedly screwed or fixedly clamped, at least in two positions, but preferably in all or in a plurality of positions, relative to the transponder 3. The screen 4 may in this case be, as illustrated, a metal sleeve into which the transponder 3 can be inserted and which forms a mount for the transponder 3. In the inserted position, the screen 4 completely covers the coil 10a, thereby achieving a maximum possible attenuation. The closed position limiting distance is the smallest in this position, that is to say that the transponder 3 has to be very near to the transceiver 5 in order that the position switch signals a completely closed state. If the transponder 3 is not inserted into the screen 4, the attenuation is the least and the closed position limiting distance is the largest, that is to say that the completely closed position is signaled even when there is a large distance between transponder 3 and transceiver 5. If the transponder 3 is only partially inserted into the screen 4, the attenuation and thus the closed position limiting distance lies between the two extreme values.
Instead of being a metal sleeve, the screen 4 may also be formed as a metal sheet or a grid or some other structure which, in an attenuating position, covers at least part of the coil 10a of the transponder 3. The screen 4 may additionally or alternatively also be provided on the transceiver 5.
In the case of the embodiment illustrated in FIG. 2, provision is made of two transponders 3a, 3b arranged on a stationary or movable, for instance longitudinally displaceable, part 11 at a distance from one another in the direction of movement. For each of the two transponders 3a, 3b, there is a coil 9a, 9b arranged in a stationary manner in this regard, which coils are in each case connected to a separate transceiver 6a, 6b, which, for their part, are connected to an evaluation logic 12. If appropriate, the coils 9a, 9b may enclose the part 11, as illustrated. The part 11 and a screen 4, for instance a screening sleeve, are movable relative to one another for instance between two end positions, so that the screen 4, in the respective end position, can screen one of the two transponders 3a, 3b with respect to its coil 9a or 9b.
The part 11, for instance, a bolt, may be movable in its longitudinal direction in accordance with the arrow 14 for example on a closing part such as a gate, while the screen 4 is arranged on a with regard to the closing part stationary closable part in the form of a wall, fencing or the like with gate or access opening in a machine lining, machine fencing or the like, or is Notionally coupled thereto. In accordance with the relative position of the screen 4 with regard to the respective transponder 3a, 3b, it is thus possible to establish the closed or open state of the closing part. If an echo with a sufficient level does not come from any of the transponders 3a, 3b, the closing part is open. If an echo returns from both transponders 3a, 3b or only from a specific one of the two transponders 3a, 3b, the closed position has not yet been reached. If, by contrast, only the other specific one of the two transponders 3a, 3b responds, the closing part is in the closed state with respect to the part that can be closed off.
What may also be involved in this case, however, is a part e.g. sliding gate, that can be extended or moved with respect to another part, so that it is possible to establish whether the retracted or extended state of the screen-carrying part, for instance, with respect to the part 11 that carries the transponders 3a, 3b is present.
If appropriate, provision may be made of more than two transponders 3a, 3b arranged at a distance relative to one another with associated coils and transceivers in order to detect different states of extension that are determined by the screening of one of the transponders by the screen.
If appropriate, a further transponder 14a, 14b may also be provided in a manner arranged in stationary fashion with respect to each of the at least two coils 9a, 9b, which further transponder can be addressed by the respective coil 9a, 9b in order thus to be able to test the functionality of the position monitoring device.
If a plurality of position switches are provided, the respective housing 13 may be provided with at least one window 15, while at least one additional transponder 14a, 14b is arranged on the part to which the housing 13 is fixed, which transponder can be permanently detected by a corresponding coil 9a, 9b in order to supply a corresponding address for the respective position switch in order to be able to distinguish between signals of position switches situated at different locations on the bus 7. The abovementioned possibility of testing for functionality is afforded if a respective transponder 14a, 14b is present for a respective coil 9a, 9b.
In the case of the embodiment of FIG. 3 the screen 4 consists of a sheet strip provided with equidistant holes 16 and is fastened at the moving part 1, whereby the transponder 3 and the transceiver 5 are stationary with respect to part 1 and thus to screen 4. Thus, a kind of an electromagnetic “light barrier” by which for instance the rotational or longitudinal speed of part 1 with respect to part 2 can be determined according to the time distance of detecting the transponder 3 between the interruptions provided by the screen 4.
In the case of the embodiment of FIG. 4 in the form of a cable line switch, part 1 in the form of a plunger provided with two transponders 3a, 3b spaced to each other in longitudinal direction of part 1 is guided within a housing 17, extends to the outside of the housing 17 and is provided with a cable line 18 which normally is in tension. Two screens 4a, 4b which may be sleeve-like and are able to screen the transponders 3a, 3b against the coil 9 of the transceiver 5 are provided. Part 1 is biased by a spring 19 with respect to the housing 17 in the direction against the tension of the cable line 18. The cable line 18 holds part 1 in a starting position which is a medium position between the transponders 3a, 3b and thus between the screens 4a, 4b so that both transponders 3a, 3b are in the reading area of the coil 9. In the case the cable line 18 is actuated, i.e. is pulled, the transponder 3b reaches the area of the screen 4b and is thus no more detectable by the coil 9. This provides the release of a corresponding signal via the coil 9. In the case the cable line 18 ruptures so that the cable line switch is out of order, the spring 19 pushes part 1 in a position wherein the transponder 3a reaches the area of the screen 4a so that the transponder 3a is no more detectable by the coil 9. Because of the transponder codes thus a failure of the switch is detectable and a corresponding disorder signal can be produced.
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