JP2007224940A - Position detection device for hydraulic cylinder and driving state setting method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust so that a proper detection signal can be output from a position detection device even when a mounting position of the position detection device attached to a hydraulic cylinder cannot be manually adjusted in a state wherein the hydraulic cylinder is installed in a predetermined installation position. <P>SOLUTION: The position detection device 10 is provided with a plurality of magnetic sensors Sa to Sd, a magnetic sensor selection circuit for selectively setting one of the plurality of the magnetic sensors in an operable state, and an outside operation means capable of setting the magnetic sensor selection circuit in a desirable output state. The magnetic sensors Sa to Sd are arranged along a moving direction of a piston 12 in the state wherein the position detecting device 10 is attached to the hydraulic cylinder 11, and are arranged so that a part of an operation region of adjacent magnetic sensors is overlapped. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluid pressure cylinder position detection device and a driving state setting method of the fluid pressure cylinder position detection device, and more specifically, detects a piston position of a fluid pressure cylinder using an MR element (magnetoresistance element). The present invention relates to a fluid pressure cylinder position detection device and a driving state setting method for a fluid pressure cylinder position detection device.

  Conventionally, a fluid pressure cylinder using fluid pressure, such as an air cylinder, is known. When this type of fluid pressure cylinder is used, it is usually necessary to detect the position of the piston in some stroke by some means. As a means for realizing detection of such a piston position, a fluid pressure cylinder position detection device (hereinafter simply referred to as a magnetic sensor) having one magnetic sensor having an MR element (magnetoresistive element) as a detection element. (In some cases, it is also referred to as a position detection device.) (See, for example, Patent Document 1).

These position detection devices are fluid pressure cylinders that are movable along mounting grooves formed on the outer peripheral surface of the fluid pressure cylinder so as to extend in the direction of movement of the piston rod, and can be fixed with a fixing screw at an arbitrary position. Attached to. When attaching the position detection device to the fluid pressure cylinder, engage the position detection device with the attachment groove, move the piston along the attachment groove to the position where you want to detect it, and then turn the fixing screw with a screwdriver to fix it. It was.
Japanese Patent Laid-Open No. 10-38628

  There is no problem if the installation position of the fluid pressure cylinder with the position detection device relative to the device main body is a position where the position of the position detection device can be adjusted. However, with the miniaturization of today's devices, the installation location of the fluid pressure cylinder may not be able to manually adjust the attachment position of the position detection device attached to the fluid pressure cylinder. In that case, before the fluid pressure cylinder was installed in the apparatus main body, the position detecting device was attached to the fluid pressure cylinder in accordance with the approximate piston stop position, and it was assembled in the apparatus main body.

  However, in this assembling method, there is no problem if the stop position of the piston matches the operating position of the position detection device when the fluid pressure cylinder is driven. However, if the actual operating stroke is deviated from the full stroke of the piston, the operation may become unstable or stop working at all due to stopping in the hysteresis zone of the position detection device. It was. In this case, after disassembling the assembled device, taking out the corresponding fluid pressure cylinder with the position detection device, correcting the mounting position of the position detection device, and then reassembling the device, enormous man-hours and labor costs are required. It was.

  The object of the present invention is to detect the position even when the mounting position of the position detecting device attached to the fluid pressure cylinder cannot be manually adjusted when the fluid pressure cylinder is installed at a predetermined installation location. An object of the present invention is to provide a fluid pressure cylinder position detecting device and a driving state setting method thereof that can be adjusted to a state in which an appropriate detection signal can be output from the device.

  In order to achieve the above object, according to the first aspect of the present invention, the output voltage of the magnetoresistive element showing the resistance value corresponding to the strength of the magnetic field from the magnetism generating means is compared with the reference voltage by the comparator and compared. A position detection device for a fluid pressure cylinder provided with a magnetic sensor for outputting a result, wherein the position detection device is disposed along a moving direction of a piston of the fluid pressure cylinder when the position detection device is attached to the fluid pressure cylinder. And a plurality of the magnetic sensors arranged so that a part of the operation range of adjacent magnetic sensors overlaps, and a magnetic sensor selection circuit for setting the plurality of magnetic sensors in a state in which they can be selectively operated And an external operation means capable of setting the magnetic sensor selection circuit to a desired output state.

  In the state where the position detection device of the present invention is attached to the fluid pressure cylinder, the plurality of magnetic sensors are arranged along the moving direction of the piston of the fluid pressure cylinder. Therefore, the range in which the position detection device can be operated by the magnetic field of the magnetic generation means is wider than that of a conventional position detection device having one magnetic sensor. Then, by operating the magnetic sensor selection circuit by the external operation means, it becomes possible to set a desired magnetic sensor in a drivable state. Therefore, when the fluid pressure cylinder is installed at a predetermined installation location, even if the mounting position of the position detector attached to the fluid pressure cylinder cannot be manually adjusted, the position detector can It can be adjusted to a state in which the detection signal can be output.

  According to a second aspect of the present invention, in the first aspect of the present invention, the magnetic sensor selection circuit is externally connected via a lead wire that is pulled out from the position detection device and forms at least a part of the external operation means. It is possible to operate. According to the present invention, when the position detection device is assembled to the fluid pressure cylinder, the position detection device can be mounted within the range of the lead wire length without changing the position of the position detection device. It is possible to freely adjust to a state where an appropriate detection signal can be output.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the magnetic sensor selection circuit includes a logic circuit that can operate any one of the plurality of magnetic sensors. ing. Therefore, according to the present invention, it is possible to accurately detect that the piston of the fluid pressure cylinder has reached a predetermined position as compared with a case where a plurality of adjacent magnetic sensors are set in a drivable state.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the magnetic sensor selection circuit sets the magnetic sensor that can be driven depending on a connection state of the lead wire to a power source or a ground. In the present invention, the magnetic sensor is driven by changing the connection state of the lead wire to the power source or the ground while the position detection device is assembled to the device together with the fluid pressure cylinder and the piston is stopped at a desired stop position. Check possible connection status. And it can set to the state which a position detection apparatus performs required detection operation by setting to the state.

  According to a fifth aspect of the present invention, in the first or second aspect of the present invention, the magnetic sensor selection circuit includes a microcomputer. In the present invention, the number and combination of magnetic sensors that can be operated can be freely and easily set as compared with the case where the magnetic sensor selection circuit includes a logic circuit.

  According to a sixth aspect of the invention, in the fifth aspect of the invention, the magnetic sensor selection circuit sets the magnetic sensor that can be driven by a signal from an external setting means connected to the lead wire. . In the present invention, an operation for storing in the memory of the microcomputer the operation content indicating which magnetic sensor can be operated by the microcomputer can be performed by a signal from the external setting means.

  According to a seventh aspect of the present invention, the microcomputer according to the fifth aspect of the present invention is configured such that the microcomputer performs the plurality of magnetic operations based on an ON operation of a setting switch provided in an external setting unit connected to the lead wire. One magnetic sensor that should be in an operable state is automatically retrieved from the sensors, and only the magnetic sensor is set in an operable state. In the present invention, only one magnetic sensor that should be in an operable state can be easily set in an operable state.

  The invention according to claim 8 is the invention according to claim 7, wherein the microcomputer performs the search by using an output signal of the magnetic sensor in a state where the position detecting device is assembled in a device. According to the present invention, one magnetic sensor that should be operable can be set easily and accurately.

  According to a ninth aspect of the present invention, in the invention according to any one of the first to eighth aspects, each of the magnetic sensors can be displayed in order to display which of the plurality of magnetic sensors is in an operating state. An indicator lamp that is lit in correspondence with the operation of each magnetic sensor is provided. In the present invention, the user can visually determine which magnetic sensor is in an operable state.

  According to a tenth aspect of the present invention, in the invention according to the seventh or eighth aspect, the microcomputer sets one specific magnetic sensor to an operable state in an initial state, and the magnetic sensor There are provided a first indicator lamp that lights in correspondence with the operation of the above, and a second indicator lamp that lights up in correspondence with the operation of the other magnetic sensor. In the present invention, the user can visually determine whether the magnetic sensor that is currently operable is a magnetic sensor that is operable in the initial state.

  According to the eleventh aspect of the present invention, the output voltage of the magnetoresistive element showing the resistance value corresponding to the strength of the magnetic field from the magnetism generating means in the state attached to the fluid pressure cylinder is compared with the reference voltage by the comparator. A plurality of magnetic sensors for outputting the comparison results are arranged along the moving direction of the piston of the fluid pressure cylinder so that a part of the operation range of the adjacent magnetic sensors overlaps, and the plurality of magnetic sensors A drive state setting method for a fluid pressure cylinder position detecting device having a magnetic sensor selection circuit for setting a sensor in a selectively operable state, wherein the fluid pressure cylinder is incorporated in the device and the fluid pressure is The magnetic sensor selection is performed by an external operation so that the magnetic sensor corresponding to the magnetism generating means can be driven in a state where the cylinder is operated and the piston is stopped at a desired position. To set the output state of the circuit.

  In the present invention, the magnetic sensor corresponding to the stop position of the piston of the fluid pressure cylinder can be obtained without changing the attachment position of the position detection device with respect to the fluid pressure cylinder in a state where the fluid pressure cylinder is assembled to the device. It can be in an operable state. Therefore, when the fluid pressure cylinder is installed at a predetermined installation location, even if the mounting position of the position detector attached to the fluid pressure cylinder cannot be changed manually, an appropriate It can be adjusted to a state in which the detection signal can be output.

  According to the present invention, in a state where the fluid pressure cylinder is installed at a predetermined installation location, even if the position of the position detector attached to the fluid pressure cylinder cannot be changed manually, the position detection is performed. It is possible to adjust to a state in which an appropriate detection signal can be output from the apparatus.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
A fluid pressure cylinder position detection device (hereinafter simply referred to as a position detection device) is used for detecting a piston position in a fluid pressure cylinder such as an air cylinder or a hydraulic cylinder. As shown in FIG. 1 (b), the position detecting device 10 is movable along an attachment groove 13 formed on the outer peripheral surface of the fluid pressure cylinder 11 so as to extend along the moving direction of the piston rod 12a. It is attached to the fluid pressure cylinder 11 so that it can be fixed by a fixing screw 14 at a position. As shown in FIG. 1A, a magnet 16 is provided in the accommodation groove 15 formed on the outer peripheral surface of the piston 12. The position detection device 10 is configured to generate an output signal when the magnet 16 moves together with the piston 12 to a predetermined position. Although not shown, the mounting groove 13 is also provided on the other surface of the fluid pressure cylinder 11 so that the mounting position of the position detection device 10 can be appropriately changed.

  As shown in FIG. 1A, the position detection device 10 includes various electronic components. These electronic components are mounted on the circuit board 17. As the electronic components, there are a plurality (four in this embodiment) of magnetic sensors Sa, Sb, Sc, Sd, a light emitting diode 18, a regulator circuit 19, and transistors and resistors not shown. Various electronic components and the circuit board 17 are accommodated in the case 20. The four magnetic sensors Sa, Sb, Sc, and Sd are arranged along the moving direction of the piston 12 when the position detecting device 10 is attached to the fluid pressure cylinder 11, and the operating range (ON (Section) is disposed in the case 20 so as to partially overlap. FIG. 1A schematically shows the configuration of the position detection device 10. For convenience of illustration, in order to exaggerate some dimensions and make it easy to understand, the width of each part, The ratio of dimensions such as length and thickness is different from the actual ratio.

  As shown in FIG. 2, each magnetic sensor Sa, Sb, Sc, Sd includes an MR element (magnetoresistance element) 21, a comparator 22, and a reference voltage generation circuit 23. The MR element 21 is connected between the power supply Vcc and the ground GND, and the output terminal is connected to the non-inverting input terminal of the comparator 22. The reference voltage generation circuit 23 includes resistors R2 and R3, and outputs a reference voltage obtained by dividing the power supply Vcc by both resistors R2 and R3 to the inverting input terminal of the comparator 22. A resistor R4 is connected between the output terminal and the non-inverting input terminal of the comparator 22 for positive feedback. The comparator 22 compares the output voltage of the MR element 21 with the generated voltage of the reference voltage generating circuit 23, and the input voltage on the non-inverting input terminal side of the comparator 22 is higher than the generated voltage of the reference voltage generating circuit 23. When it becomes larger, a signal of H (High) level is output.

  As shown in FIG. 3, each magnetic sensor Sa, Sb, Sc, Sd is connected to the power supply line via bus switches 24a, 24b, 24c, 24d. The output terminals of the magnetic sensors Sa, Sb, Sc, and Sd are wired OR connected through the diodes 25a, 25b, 25c, and 25d, and are connected to the base terminal of the first transistor Tr1 through the resistor R5. . That is, the outputs of the magnetic sensors Sa, Sb, Sc, and Sd are input to the base terminal of the first transistor Tr1. The cathode terminal of the light emitting diode 18 is connected to the collector terminal of the first transistor Tr1, and the anode terminal of the light emitting diode 18 is connected to the power source Vcc via the resistor R6. The emitter terminal of the first transistor Tr1 is connected to the base terminal of the second transistor Tr2. The emitter terminal of the second transistor Tr2 is connected to the ground GND, and the collector terminal of the second transistor Tr2 is connected to the output terminal P. The second transistor Tr2 has a collector terminal connected to the cathode terminal of the Zener diode 26 and an emitter terminal connected to the anode terminal of the Zener diode 26. That is, when an H level signal is output from any one of the magnetic sensors Sa, Sb, Sc, and Sd, the first transistor Tr1 is turned on and the light emitting diode 18 emits light. NPN transistors are used for the first and second transistors Tr1 and Tr2.

  Each of the bus switches 24a to 24d is connected to output terminals 27a, 27b, 27c, and 27d of the logic circuit 27 shown in FIG. A magnetic sensor selection circuit that sets the magnetic sensors Sa to Sd to be selectively operable by the bus switches 24a to 24d, the logic circuit 27, and the input signal generation circuit 28 that generates an input signal to the logic circuit 27. It is configured.

  The logic circuit 27 includes a first inverter (negative circuit) 29a, a second inverter 29b, a first AND circuit 30a, a second AND circuit 30b, a third AND circuit 30c, a fourth AND circuit 30d, and an exclusive OR circuit 31. The first signal generated by the input signal generation circuit 28 is input to the first AND circuit 30a, the second AND circuit 30b, the exclusive OR circuit 31 and the first inverter 29a. The second signal generated by the input signal generation circuit 28 is input to the first AND circuit 30a, the third AND circuit 30c, the exclusive OR circuit 31 and the second inverter 29b. The output terminal of the exclusive OR circuit 31 is connected to the second AND circuit 30b and the third AND circuit 30c. The output terminals of the first inverter (negative circuit) 29a and the second inverter 29b are connected to the fourth AND circuit 30d.

  The input signal generation circuit 28 that generates an input signal to the logic circuit 27 includes a first series circuit 32a of a resistor R7 and a transistor Tr3, and a second series circuit 32b of a resistor R8 and a transistor Tr4. Series circuits 32a and 32b are connected in parallel to the power supply Vcc. The first signal is output from the first series circuit 32 a to the logic circuit 27, and the second signal is output from the second series circuit 32 b to the logic circuit 27. PNP transistors are used for the transistors Tr3 and Tr4.

  The transistor Tr3 has an emitter terminal connected to the power supply Vcc via the resistor R7, a collector terminal connected to the GDN (grounded), and a base terminal connected to the first lead wire 33a constituting the external operation means. ing. The transistor Tr4 has an emitter terminal connected to the power supply Vcc via the resistor R8, a collector terminal connected to the GDN, and a base terminal connected to the second lead wire 33b constituting the external operation means. As shown in FIG. 1A, the first and second lead wires 33a and 33b are connected to the outside of the case 20 by a cabtyre cord together with the power source wire 34, the ground wire 35 and the output wire 36 of the position detecting device 10. Has been pulled out. The input of the first lead wire 33a is represented as A, and the input of the second lead wire 33b is represented as B.

  Since the components constituting the magnetic sensors Sa to Sd, the logic circuit 27, the input signal generation circuit 28, and the like have a low withstand voltage, their driving is generally low voltage driving such as DC5V. The regulator circuit 19 is used to step down DC24V to DC5V so that it can be used with a generally used DC24V direct current stabilized power supply. The regulator circuit 19 includes, for example, a diode 38, a transistor Tr5, a resistor R9, capacitors C1 and C2, and a Zener diode 39 as shown in FIG. An NPN transistor is used as the transistor Tr5. The diode 38 has an anode terminal connected to the power supply line 34 and a cathode terminal connected to the collector terminal of the transistor Tr5. The Zener diode 39 has an anode terminal connected to the ground line 35 and a cathode terminal connected to the base terminal of the transistor Tr5. The resistor R9 is connected between the base terminal and the collector terminal of the transistor Tr5. The capacitor C1 is connected between the cathode terminal of the diode 38 and the ground line 35, and the capacitor C2 is connected between the emitter terminal of the transistor Tr5 and the ground line 35.

Next, the operation of the position detection device 10 configured as described above will be described.
The position detection device 10 is attached to a predetermined position of the fluid pressure cylinder 11, and, as shown in FIG. 6, the power line 34 is connected to the positive terminal side of the DC stabilized power source 40 of DC 24V, and the ground line 35 is DC stabilized. Connected to the negative terminal side of the power supply 40. Further, the output line 36 is connected to the load 41. Examples of the load 41 include a programmable controller. Then, the direct current 24V voltage supplied from the DC stabilized power supply 40 is stepped down to the direct current 5V by the regulator circuit 19 and used as the power supply Vcc of the position detection device 10.

  In a state in which the position detection device 10 is attached to the fluid pressure cylinder 11, a plurality of magnetic sensors Sa to Sd are arranged along the moving direction of the piston 12 of the fluid pressure cylinder 11, and thus one magnetic sensor is provided. Compared with the conventional position detecting device, the range in which the position detecting device 10 can operate by the magnetic field of the magnet 16 is widened.

  As shown in FIG. 3, the output terminals of the plurality of magnetic sensors Sa to Sd are wired OR connected, and their output signals are input to the base terminal of the first transistor Tr1. Therefore, when an H level signal is output from any one of the magnetic sensors Sa to Sd, the first transistor Tr1 is turned on, the light emitting diode 18 is turned on, and the base terminal of the second transistor Tr2 is turned on. An H level signal is input to. As a result, the second transistor Tr2 is also turned on, and an L level signal is output to the output line 36 of the position detection device 10. Then, the signal is input to the programmable controller via the output line 36 to inform that the position of the piston 12 is a predetermined position, and the entire apparatus is responsible for operating in order.

  Since the strength of the magnetic force of the permanent magnet changes depending on the temperature, if the magnetic sensors Sa to Sd are arranged so that their operating ranges do not overlap at a certain temperature and the operating ranges are continuous, the piston 12 is magnetized depending on the temperature. Stopping in the sensor's hysteresis range may cause unstable operation or a state in which the magnetic sensor does not operate. However, as shown in FIG. 7, each of the magnetic sensors Sa to Sd is disposed so that a part of the operation range of the adjacent magnetic sensors overlaps, so that the occurrence of the above-described problem is avoided.

  When the position detection device 10 is installed so that the piston rod 12a is fully extended and the magnetic sensor Sa is operated, the first and second lead wires 33a and 33b are connected to the power source and the ground. It is in an unwired state. Therefore, the emitter terminals of the transistors Tr3 and Tr4 of the input signal generation circuit 28 shown in FIG. 4 are both at the H level. At this time, from the truth table shown in Table 1, since only the output terminal 27a of the logic circuit 27 becomes H level, only the bus switch 24a connected to the output terminal 27a is turned on, and only the magnetic sensor Sa can be driven. Become.

この位置検出装置１０が取り付けられた流体圧シリンダ１１が組み込まれた装置が完成し、試運転を行った時、磁石１６を備えたピストン１２が磁気センサＳａの動作範囲で停止せず、位置検出装置１０が動作しない（オンしない）不具合が発生する場合がある。その主な原因は、ピストンロッド１２ａの先端に取り付けられたスライドユニット等の治工具のストロークがシリンダフルストロークよりも若干短めに設計されることが多々あり、その値は設計者個々あるいは物件毎に異なることである。

When a device incorporating the fluid pressure cylinder 11 to which the position detection device 10 is attached is completed and a trial operation is performed, the piston 12 including the magnet 16 does not stop within the operation range of the magnetic sensor Sa, and the position detection device. 10 may not operate (does not turn on). The main cause is that the stroke of a jig such as a slide unit attached to the tip of the piston rod 12a is often designed to be slightly shorter than the cylinder full stroke, and the value depends on the individual designer or property. Is different.

  In such a case, conventionally, if the position of the position detection device is within the reach of the operator, the fixing screw 14 of the position detection device 10 is loosened with a screwdriver and moved to a position where the position detection device operates. Was fixed again. However, if the position of the position detection device is not within the reach of the operator, it is necessary to disassemble the device, take out the fluid pressure cylinder, readjust the mounting position of the position detection device, and then assemble the device There is.

  However, when the position detection device 10 of this embodiment is used, if the position detection device 10 does not operate during the trial operation of the device, an operation of changing (adjusting) the position of the position detection device 10 attached to the fluid pressure cylinder 11 is performed. First, this can be dealt with by changing the connection state of the first and second lead wires 33a and 33b to the ground (GND). That is, the first and second lead wires 33a and 33b constituting the external operation means are operated to set any one of the magnetic sensors Sa to Sd to an operable state.

  Specifically, for example, when the piston 12 is stopped at a position corresponding to the magnetic sensor Sb, the bus switch 24b corresponding to the magnetic sensor Sb is turned on, that is, the H level from the output terminal 27b. The second lead wire 33b is connected to GND so that a signal is output, and the first lead wire 33a is used without being wired. In this state, an H level signal is output from the first series circuit 32a and an L level signal is output from the second series circuit 32b. Therefore, an H level signal is output from the output terminal 27b. .

  When the piston 12 is stopped at a position corresponding to the magnetic sensor Sc, the bus switch 24c corresponding to the magnetic sensor Sc is turned on, that is, a state where an H level signal is output from the output terminal 27c. As described above, the first lead wire 33a is connected to GND, and the second lead wire 33b is used without being wired. In this state, since an L level signal is output from the first series circuit 32a and an H level signal is output from the second series circuit 32b, an H level signal is output from the output terminal 27c. .

  When the piston 12 is stopped at a position corresponding to the magnetic sensor Sd, the bus switch 24d corresponding to the magnetic sensor Sd is turned on, that is, an H level signal is output from the output terminal 27d. The first lead wire 33a and the second lead wire 33b are connected to GND so as to be in a state. In this state, since an L level signal is output from the first series circuit 32a and an L level signal is also output from the second series circuit 32b, an H level signal is output from the output terminal 27d. . In this way, by selecting whether the first and second lead wires 33a and 33b are connected to GND or used in an unwired state, the piston 12 can be selected from the plurality of magnetic sensors Sa to Sd. The magnetic sensor corresponding to the stopped position is set to an operable state.

According to this embodiment, the following effects can be obtained.
(1) The position detection device 10 includes a plurality of magnetic sensors Sa to Sd. The plurality of magnetic sensors Sa to Sd are disposed along the moving direction of the piston 12 in a state where the position detection device 10 is attached to the fluid pressure cylinder 11 and are part of the operation range of adjacent magnetic sensors. Are arranged so as to overlap each other. In addition, a magnetic sensor selection circuit (logic circuit 27, input signal generation circuit 28, etc.) that sets a plurality of magnetic sensors Sa to Sd to a state in which they can be selectively operated, and a magnetic sensor selection circuit are set to a desired output state. Possible external operation means (first and second lead wires 33a, 33b). Therefore, in a state where the fluid pressure cylinder 11 is installed at a predetermined installation location, even if the attachment position of the position detection device 10 attached to the fluid pressure cylinder 11 cannot be manually adjusted, the position detection device. 10 can be adjusted so that an appropriate detection signal can be output.

  (2) The magnetic sensor selection circuit can be externally operated via the first and second lead wires 33 a and 33 b drawn from the position detection device 10. Therefore, when the position detection device 10 is assembled to the fluid pressure cylinder 11 and assembled to the device, the position of the lead wires 33a and 33b can be maintained without changing the mounting position of the position detection device 10. The position detection device 10 can be freely adjusted to a state in which an appropriate detection signal can be output.

  (3) The magnetic sensor selection circuit includes a logic circuit 27 that enables any one of the plurality of magnetic sensors Sa to Sd to operate. Therefore, it is possible to accurately detect that the piston 12 of the fluid pressure cylinder 11 has reached a predetermined position as compared with a case where a plurality of adjacent magnetic sensors are set in a drivable state.

  (4) Since the magnetic sensor selection circuit sets a magnetic sensor that can be driven by the connection state of the first and second lead wires 33a and 33b to the ground (GDN), the setting operation is simple.

  (5) When the fluid pressure cylinder 11 to which the position detection device 10 is attached is incorporated in the device and the fluid pressure cylinder 11 is operated and the piston 12 is stopped at a desired position, the piston 12 (magnet 16) and The output state of the magnetic sensor selection circuit is set by an external operation so that the corresponding magnetic sensor can be driven. Therefore, by operating the magnetic sensor selection circuit in the actual operating environment of the position detection device 10, it is possible to easily set a magnetic sensor that can be operated from among the plurality of magnetic sensors Sa to Sd.

  (6) The first series circuit 32a and the second series circuit 32b that constitute the input signal generation circuit 28 each output an H level signal when the first and second lead wires 33a and 33b are not wired. The first and second lead wires 33a and 33b are configured to output an L level signal in a state of being connected to the GDN. Therefore, the signals output from the first series circuit 32a and the second series circuit 32b in the state where the first and second lead wires 33a and 33b are not wired and the state where they are connected to the power source (plus) are set to the H level. Compared with the configuration for switching to the L level, power consumption can be reduced.

  (7) Since the position detection device 10 includes the regulator circuit 19, the position detection device 10 can be used without providing a 5 V power supply exclusively for the position detection device 10 in a device including the general-purpose 24 V DC stabilized power supply 40. it can.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. This embodiment includes a microcomputer in place of the logic circuit 27 constituting the magnetic sensor selection circuit for selectively setting a plurality of magnetic sensors Sa to Sd to be operable, and an input signal generation circuit. The configuration of 28 is different from that of the first embodiment, and the other configurations are the same. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 8, a one-chip microcomputer (one-chip microcomputer) 42 as a microcomputer constituting the magnetic sensor selection circuit has five output terminals GP0, GP1, GP2, GP4, GP5 and one input terminal. GP3 is provided. The output terminal GP0 is connected to the bus switch 24d, the output terminal GP1 is connected to the bus switch 24c, the output terminal GP2 is connected to the bus switch 24b, and the output terminal GP4 is connected to the bus switch 24a.

  The input signal generation circuit 28 includes a first series circuit 32a including a resistor R7 and a transistor Tr3. The transistor Tr3 has an emitter terminal connected to the power supply Vcc via the resistor R7, a collector terminal connected to the GDN (grounded), and a base terminal connected to the first lead wire 33a constituting the external operation means. ing. An intermediate point between the resistor R7 and the emitter terminal of the transistor Tr3 is connected to the input terminal GP3 of the one-chip microcomputer 42.

  The collector terminal of the transistor Tr6 is connected to the power source Vcc via a resistor R10. The transistor Tr6 has a base terminal connected to the output terminal GP5 of the one-chip microcomputer 42 via the resistor R11, and an emitter terminal connected to the second lead wire 33b. That is, in the second embodiment, unlike the first embodiment, the input signal generation circuit 28 does not output a set of signals A and B, but only the output signal of the first series circuit 32a. 42.

  A ROM (not shown) of the one-chip microcomputer 42 stores a program for performing the operations shown in Table 2. As the operation contents, only one of the four output terminals GP0, GP1, GP2, GP4 is set to the H level, the operation of setting any two to the H level, and any three of them. There are an operation to set the H level and an operation to set all four to the H level. The one-chip microcomputer 42 stores the operation content instructed by the external setting means 43 (shown in FIG. 9) connected via the first and second lead wires 33a and 33b in an EEPROM (not shown). It is supposed to be.

図９に示すように、外部設定手段４３は、設定スイッチ４４及び設定確認表示灯４５を備えている。設定確認表示灯４５は発光ダイオードで構成されている。外部設定手段４３は、設定スイッチ４４の一端がアース線に接続され、他端が第１のリード線３３ａに接続されるとともに、設定確認表示灯４５を構成する発光ダイオードのカソード端子がアース線に接続され、アノード端子が第２のリード線３３ｂに接続された状態で使用されるようになっている。

As shown in FIG. 9, the external setting means 43 includes a setting switch 44 and a setting confirmation indicator lamp 45. The setting confirmation indicator lamp 45 is composed of a light emitting diode. In the external setting means 43, one end of the setting switch 44 is connected to the ground wire, the other end is connected to the first lead wire 33a, and the cathode terminal of the light emitting diode constituting the setting confirmation indicator lamp 45 is connected to the ground wire. The anode terminal is connected and used in a state of being connected to the second lead wire 33b.

  The one-chip microcomputer 42 operates based on a signal input to the input terminal GP3 corresponding to the pressing length and the number of times of the setting switch 44, and overwrites the instructed operation content on the EEPROM. Further, the one-chip microcomputer 42 outputs a signal for turning on the setting confirmation indicator lamp 45 from the output terminal GP5 based on a signal input to the input terminal GP3. The pressing operation of the setting switch 44 includes a long press and a short press, and there are 10 types of the press operation: one long press and 1 to 9 short presses. In this embodiment, a program of operations to be performed by the one-chip microcomputer 42 is stored in the ROM in response to ten types of pressing operations of the setting switch 44.

  The long press of the setting switch 44 once is an instruction for initialization and an instruction for outputting an H level signal only to the output terminal GP4. When the one-time long press is performed, the one-chip microcomputer 42 outputs an H level signal from the output terminal GP5 so that the setting confirmation display lamp 45 is always turned on from OFF (extinguishment). When a short press is performed, the setting confirmation display lamp 45 is turned off simultaneously with the pressing, and after the bus switch switching operation is completed, the setting confirmation display lamp 45 blinks once as a setting completion signal.

  Even when the position detection device 10 of this embodiment is used, as in the first embodiment, a device incorporating the fluid pressure cylinder 11 to which the position detection device 10 is attached is completed, and position detection is performed in the trial operation of the device. If the apparatus 10 does not operate, the external setting means 43 is connected to the first and second lead wires 33a and 33b to reset the setting.

  For example, if the position detection device 10 does not turn on in the setting state in which the magnetic sensor Sa is operable, that is, the setting in which only the output terminal GP4 outputs an H level signal, the initial setting is considered to correspond to the stop position of the piston 12. In order to enable the magnetic sensor to be operated, for example, the magnetic sensor Sc, the setting switch 44 is short-pressed twice. When the one-chip microcomputer 42 is short-pressed, the one-chip microcomputer 42 turns off the setting confirmation indicator lamp 45 and then turns on the setting confirmation indicator lamp 45 as a setting completion signal. After the setting is completed, the external setting means 43 is removed. Since the set conditions are stored in the EEPROM, unless the settings are reset, they will not disappear even if the power of the apparatus is turned off at the end of the work. Therefore, the magnetic sensor that can operate before and after the power is turned off is not changed. When changing the setting condition, it may be changed by performing a short press for a predetermined number of times corresponding to the operation after the change, but after performing a long press as an initialization operation once, a short press should be performed. May be.

  In this embodiment, unlike the first embodiment, it is possible to set not only a setting condition that enables only one of the plurality of magnetic sensors Sa to Sd but also a plurality of magnetic sensors to be operable. It is. Therefore, for example, it is the role of the fluid pressure cylinder 11 to fix the work, and when the stop position of the piston 12 varies as in the case where there is a large difference in the dimensions of the work to be fixed, a plurality of magnetic sensors are used. By setting it to be operable, it can be confirmed that the piston rod 12a has moved to the position where the workpiece is fixed, regardless of the size of the workpiece.

Therefore, according to this embodiment, the following effects can be obtained in addition to the same effects as (1), (2), (5), and (7) in the first embodiment.
(8) Since the magnetic sensor selection circuit includes the one-chip microcomputer 42, the number and combination of magnetic sensors to be operable can be freely set as compared with the case where the magnetic sensor selection circuit includes the logic circuit 27. And can be set easily.

  (9) The operation content of the one-chip microcomputer 42 which one of the magnetic sensors the one-chip microcomputer 42 can operate according to the signal from the external setting means 43 connected to the first and second lead wires 33a and 33b. Can be stored in the memory of the one-chip microcomputer 42.

  (10) Since the EEPROM is used as a memory for storing the operation content indicating which magnetic sensor is operable, the stored content is not erased even when the power of the device is turned off. In comparison, there is no need to set conditions each time the apparatus is started.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS. This embodiment is the same as the second embodiment in that it includes a microcomputer that constitutes a magnetic sensor selection circuit that sets a plurality of magnetic sensors in a selectively operable state. However, the second embodiment is that, from the plurality of magnetic sensors, one appropriate magnetic sensor that can be operated in accordance with the installation state of the fluid pressure cylinder can be automatically set in an operable state. It is very different. The same parts as those in the first and second embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 10, the output terminals of the magnetic sensors Sb, Sc, and Sd are wired OR connected through the diodes 25b, 25c, and 25d, and are connected to the base terminal of the transistor Tr11 through the resistor R5. Yes. The output terminal of the magnetic sensor Sa is connected to the base terminal of the transistor Tr12 via the resistor R5. The collector terminal of the transistor Tr11 is connected to the cathode terminal of the light emitting diode LED1 as the first indicator lamp, and the anode terminal of the light emitting diode LED1 is connected to the power supply Vcc via the resistor R6. The collector terminal of the transistor Tr12 is connected to the cathode terminal of the light emitting diode LED2 as the second indicator lamp, and the anode terminal of the light emitting diode LED2 is connected to the power supply Vcc via the resistor R6. The emitter terminals of the transistors Tr11 and Tr12 are connected to the base terminal of the transistor Tr13. The emitter terminal of the transistor Tr13 is connected to the ground GND, and the collector terminal of the transistor Tr13 is connected to the output terminal P. A Zener diode 26 is connected between the collector terminal and the emitter terminal of the transistor Tr13, and a resistor R51 is connected between the base terminal and the emitter terminal of the transistor Tr13.

  As shown in FIG. 11, the one-chip microcomputer 42 includes four output terminals GP0, GP1, GP2, GP4 and two input terminals GP3, GP6. The input signal generation circuit 28 is configured in the same manner as in the first embodiment. The input terminal GP3 is connected to the emitter terminal of the transistor Tr3, and the input terminal GP6 is connected to the emitter terminal of the transistor Tr4.

  The ROM (not shown) of the one-chip microcomputer 42 can automatically operate an appropriate magnetic sensor that can operate according to the installation state when the fluid pressure cylinder 11 is incorporated in the apparatus. The program to be set to is stored. Specifically, the operation shown in the flowchart of FIG. 12 is performed, and only one of the four output terminals GP0, GP1, GP2, GP4 is set to the H level, and the other output terminals are set to the L level. The setting contents are stored in an EEPROM (not shown).

  As shown in FIG. 13, the external setting means 43 includes a battery 46, a terminal 47 a connected to the power supply line 34, a wiring 47 connected to the plus terminal of the battery 46, and a terminal connected to the ground wire 35. 48 a and a wiring 48 connected to the negative terminal of the battery 46. The external setting means 43 includes a setting confirmation indicator lamp 45 having a cathode terminal connected to the output line 36 and an anode terminal connected to the wiring 47, a collector terminal connected to the first lead wire 33a, and an emitter terminal connected to the wiring 48. A phototransistor 49 connected to each other, and a setting switch 44 connected between a terminal connected to the second lead wire 33 b and the wiring 48 are provided.

  When the position detection device 10 of this embodiment is used, when the device incorporating the fluid pressure cylinder 11 to which the position detection device 10 is attached is completed and the position detection device 10 does not operate in the trial operation of the device, FIG. As shown, all the wires of the position detection device 10 are connected to the terminals 47a, 48a, etc. of the external setting means 43. At the same time as the external setting means 43 is connected, the position detection device 10 is in an operating state using the battery 46 as a power source. In this state, the setting switch 44 is pressed once. By this operation, the input to the input terminal GP3 of the one-chip microcomputer 42 is changed from the H level to the L level, and the one-chip microcomputer 42 executes the operation shown in the flowchart of FIG. In the initial state, the output of the output terminal GP4 is at the H level, and the other output terminals GP0, GP1, GP2 are set at the L level. Hereinafter, the H level is abbreviated as H and the L level is abbreviated as L.

  In step S1, the one-chip microcomputer 42 determines whether or not the output of the input terminal GP6 is L. If it is L, the one-chip microcomputer 42 proceeds to step S2 to set the output of the output terminal GP4 to H and the other output terminals GP0, GP1 and GP2. After setting the output to L and writing it to the EEPROM of the one-chip microcomputer 42, the operation is terminated. If the output of the input terminal GP6 is H in step S1, the process proceeds to step S3, the output of the output terminal GP2 is set to H, and then the process proceeds to step S4.

  In step S4, the one-chip microcomputer 42 determines whether or not the output of the input terminal GP6 is L. If it is L, the one-chip microcomputer 42 proceeds to step S5 to set the output of the output terminal GP2 to H and the other output terminals GP0, GP1, and GP4. After setting the output to L and writing it to the EEPROM of the one-chip microcomputer 42, the operation is terminated. If the output of the input terminal GP6 is H in step S4, the process proceeds to step S6, the output of the output terminal GP1 is set to H, and then the process proceeds to step S7.

  In step S7, the one-chip microcomputer 42 determines whether or not the output of the input terminal GP6 is L. If it is L, the one-chip microcomputer 42 proceeds to step S8 to set the output of the output terminal GP1 to H and the other output terminals GP0, GP2 and GP4. After setting the output to L and writing it to the EEPROM of the one-chip microcomputer 42, the operation is terminated. If the output of the input terminal GP6 is H in step S7, the process proceeds to step S9, the output of the output terminal GP0 is set to H, and then the process proceeds to step S10.

  In step S10, the one-chip microcomputer 42 determines whether or not the output of the input terminal GP6 is L. If it is L, the one-chip microcomputer 42 proceeds to step S11 to set the output of the output terminal GP0 to H and the other output terminals GP1, GP2, GP4. After setting the output to L and writing it to the EEPROM of the one-chip microcomputer 42, the operation is terminated. If the output of the input terminal GP6 is H in step S10, that is, the output signal of the magnet 16 is not output from the position detection device 10 regardless of which output of all the output terminals is L, and H is input to the input terminal GP6. When not inputted, it progresses to step S12, an abnormality notification signal is output, and operation | movement is complete | finished. Then, when the operation ends without being notified of abnormality, the external setting means 43 is removed, and the position detection device 10 is connected to the original load as shown in FIG.

  When the fluid pressure cylinder 11 is reassembled or the attachment position of the position detection device 10 is changed after the setting is once completed, it is necessary to connect the external setting means 43 and perform the setting again. At that time, the power is turned on while pressing the setting switch 44, that is, the power line 34 is connected to the terminal 47a, so that the initialization is performed.

  Therefore, according to this embodiment, in addition to the same effects as (1), (2), (5), (7) in the first embodiment and (10) in the second embodiment, the following effects Can be obtained.

  (11) Among the plurality of magnetic sensors Sa to Sd, one appropriate magnetic sensor that can be operated in accordance with the installation state of the fluid pressure cylinder 11 can be set to an automatically operable state. Work becomes easy.

  (12) The one-chip microcomputer 42 should be in an operable state from among the plurality of magnetic sensors Sa to Sd using the output signals of the magnetic sensors Sa to Sd in a state where the position detection device 10 is assembled to the device. Automatically search for one magnetic sensor. Therefore, it is possible to easily and accurately set one magnetic sensor that should be operable.

  (13) The state in which the output terminal GP4 is set to H is set to the initial state, and the first state is set only when H is output from the operable magnetic sensor Sa when the output terminal GP4 is in the H state. The light emitting diode LED1 as the indicator lamp enters the light emitting state, and when H is output from the other magnetic sensors Sb, Sc, Sd, the light emitting diode LED2 as the second indicator lamp enters the light emitting state. Therefore, the user can visually determine whether the position detection device 10 is operating in the initial state or in the reset state from the light emitting state of the light emitting diodes LED1, LED2. Can do. When the light emitting diode LED1 and the light emitting diode LED2 having different emission colors are used, the discrimination becomes easy.

The embodiment is not limited to the above, and may be configured as follows, for example.
A display means may be provided for displaying that the output of each magnetic sensor Sa, Sb, Sc, Sd has become H. For example, as shown in FIG. 14, the output terminals of the magnetic sensors Sa to Sd are connected to the base terminals of the transistors Tr31, Tr32, Tr33, and Tr34 via the resistor R5, and the collector terminals of the transistors Tr31 to Tr34 emit light. The diodes LED11, LED12, LED13, LED14 and the resistor R6 are connected to the power supply Vcc. In this case, the user can visually confirm the operation status of the position detection device 10, that is, which magnetic sensor is operating. Further, the light emitting diodes LED11, LED12, LED13, and LED14 may all have different light emission colors or every other light emission color. When all the light emission colors are different, the discrimination becomes easier.

  As a method for automatically setting one magnetic sensor that should be operable from the plurality of magnetic sensors Sa to Sd by the one-chip microcomputer 42, the position of the position detection device 10 with respect to the fluid pressure cylinder 11 and the fluid The use state of the pressure cylinder 11 may be input, and one magnetic sensor that should be operable based on the value may be set. Here, the use state of the fluid pressure cylinder 11 means a deviation value from the reference position of the position where the piston 12 should be detected. For example, when the position corresponding to the extended end of the piston rod 12a is set as the reference position, it means how much the set position is used.

  Instead of providing the bus switches 24a to 24d on the power line, the input terminals of the magnetic sensors Sa to Sd may be connected to the power line and the bus switches 24a to 24d may be provided on the output line. The bus switches 24a to 24d may be provided between the output terminals of the magnetic sensors Sa to Sd and the diodes 25a to 25d, or may be provided on the cathode sorting terminal side of the diodes 25a to 25d. The bus switches 24a to 24d may be inserted between the GND terminals of the magnetic sensors Sa to Sd and the GND line.

  The input signal generation circuit 28 that generates an input signal to the logic circuit 27 outputs an H level signal to the logic circuit 27 in a state where the first and second lead wires 33a and 33b are not wired. The first and second lead wires 33 a and 33 b may be configured to output L level signals to the logic circuit 27 in a state where the first and second lead wires 33 a and 33 b are connected to the power source. For this configuration, for example, NPN transistors are used instead of PNP transistors as the transistors Tr3 and Tr4. In this case, the signals output from the first series circuit 32a and the second series circuit 32b in the state where the first and second lead wires 33a and 33b are not wired and connected to the power source (plus) are H. Switch between level and L level.

  The logic circuit 27 is used to set not only one of the plurality of magnetic sensors Sa to Sd to an operable state but also to set a plurality of magnetic sensors to an operable state. Also good. For example, in addition to the two series circuits 32a and 32b as the input signal generation circuit 28, a similar series circuit is further provided, and the number of lead wires is three. Then, the logic circuit 27 is configured such that the output state of the H level signal from the logic circuit 27 can be changed by changing the connection state of the three lead wires to the power supply or ground.

  The one-chip microcomputer 42 stores the instruction contents indicating which magnetic sensor is set in an operable state set by the instruction signal from the external setting means 43 in the RAM, instead of overwriting the EEPROM, It is also possible to input from the external setting means 43 every time it is raised.

  As each of the transistors Tr1 to Tr6, N-channel or P-channel MOS transistors (MOSFETs) may be used instead of bipolar transistors such as NPN transistors and PNP transistors.

The number of magnetic sensors is not limited to four and may be three or less or five or more.
The position detection device 10 may not be provided with the regulator circuit 19 for stepping down DC24V to DC5V, and a 5V DC power source may be provided externally (for example, a device in which the fluid pressure cylinder 11 is incorporated).

The following technical idea (invention) can be understood from the embodiment.
In the invention according to any one of claims 6 to 6, the position detection device includes a regulator that steps down DC24V to DC5V.

  The microcomputer according to claim 6 stores a plurality of programs for enabling which one of a plurality of magnetic sensors to operate in a ROM, and is a program that is executed by a signal from the external setting means Is selected, the selected content is overwritten in the EEPROM, and the operation of the overwritten content is executed.

The 1st Embodiment is shown, (a) is a schematic diagram which shows the relationship between a fluid pressure cylinder and a position detection apparatus, (b) is a model perspective view of a fluid pressure cylinder. The circuit diagram which shows the electrical constitution of a magnetic sensor. The circuit diagram which shows the relationship between each magnetic sensor and an output circuit. The circuit diagram which shows a logic circuit and an input signal generation circuit. The circuit diagram which shows a regulator circuit. The schematic diagram which shows the use condition of a position detection apparatus. The schematic diagram which shows the operating range of each magnetic sensor. The circuit diagram which shows the relationship between the one-chip microcomputer and input signal generation circuit of 2nd Embodiment. The schematic diagram explaining an effect | action. The circuit diagram which shows the relationship between each magnetic sensor and output circuit of 3rd Embodiment. The circuit diagram which shows the relationship between a one-chip microcomputer and an input signal generation circuit. The flowchart which shows operation | movement of a one-chip microcomputer. The schematic diagram of the state which connected the external setting means. The circuit diagram which shows the relationship between each magnetic sensor of another embodiment, and an output circuit.

Explanation of symbols

  Sa, Sb, Sc, Sd ... magnetic sensor, Vcc ... power supply, 10 ... position detecting device, 11 ... fluid pressure cylinder, 12 ... piston, 16 ... magnet as magnetism generating means, 22 ... comparator, 27 ... magnetic sensor selection Logic circuit constituting circuit, 33a, 33b ... lead wire constituting external operation means, 42 ... one-chip microcomputer as a microcomputer, 43 ... external setting means, 44 ... setting switch.

Claims (11)

A fluid pressure cylinder position detection device comprising a magnetic sensor for comparing the output voltage of a magnetoresistive element exhibiting a resistance value corresponding to the strength of a magnetic field from a magnetism generating means with a reference voltage and outputting a comparison result. There,
In a state where the position detection device is attached to the fluid pressure cylinder, the position detection device is disposed along the moving direction of the piston of the fluid pressure cylinder, and is disposed so that a part of the operation range of adjacent magnetic sensors overlaps. A plurality of the magnetic sensors;
A magnetic sensor selection circuit that sets a plurality of magnetic sensors in a selectively operable state;
A fluid pressure cylinder position detection device comprising: an external operation means capable of setting the magnetic sensor selection circuit to a desired output state.   The fluid pressure cylinder position detection device according to claim 1, wherein the magnetic sensor selection circuit is pulled out from the position detection device and can be externally operated via a lead wire constituting at least a part of the external operation means.   The fluid pressure cylinder position detection device according to claim 1, wherein the magnetic sensor selection circuit includes a logic circuit that enables any one of the plurality of magnetic sensors to operate.   The fluid pressure cylinder position detection device according to claim 3, wherein the magnetic sensor selection circuit sets the magnetic sensor that can be driven according to a connection state of the lead wire with respect to a power source or a ground.   The fluid pressure cylinder position detection device according to claim 1, wherein the magnetic sensor selection circuit includes a microcomputer.   The fluid pressure cylinder position detecting device according to claim 5, wherein the magnetic sensor selection circuit sets the magnetic sensor that can be driven by a signal from an external setting unit connected to the lead wire.   The microcomputer automatically selects one of the plurality of magnetic sensors to be in an operable state based on an ON operation of a setting switch provided in an external setting unit connected to the lead wire. The fluid pressure cylinder position detection device according to claim 5, wherein only the magnetic sensor is set in an operable state.   The fluid pressure cylinder position detection device according to claim 7, wherein the microcomputer performs the search by using an output signal of the magnetic sensor in a state where the position detection device is assembled in a device.   The display lamp which lights according to the operation | movement of each magnetic sensor is provided for every magnetic sensor so that it can display which of these magnetic sensors is in an operating state. The position detection apparatus for fluid pressure cylinders as described in any one of these.   In the initial state, the microcomputer is set to a state in which one specific magnetic sensor can be operated, and a first indicator lamp that lights in correspondence with the operation of the magnetic sensor, and the operations of the other magnetic sensors The fluid pressure cylinder position detecting device according to claim 7 or 8, wherein a second indicator lamp that lights up correspondingly is provided. A plurality of magnets that output the comparison results while comparing the output voltage of the magnetoresistive element that exhibits a resistance value corresponding to the strength of the magnetic field from the magnetism generating means in a state of being attached to the fluid pressure cylinder with a reference voltage and a comparator. The sensor is arranged along the moving direction of the piston of the fluid pressure cylinder so that a part of the operation range of the adjacent magnetic sensors overlaps, and a plurality of power supply lines and signal lines for driving the magnetic sensors Is a driving state setting method of a fluid pressure cylinder position detecting device including a magnetic sensor selection circuit for selectively setting the state to be operable,
The fluid pressure cylinder is operated in a state where the fluid pressure cylinder is incorporated into the apparatus, and the magnetic sensor corresponding to the magnetism generating means can be driven in an external operation so that the piston is stopped at a desired position. A driving state setting method for a position detecting device for a fluid pressure cylinder, which sets an output state of the magnetic sensor selection circuit.

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