JP2003074742A - Pilot type selector valve with valve position detecting switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pilot type selector valve with a valve position detecting switch capable of detecting the valve position of the pilot type selector valve up to three positions regardless of the pressure and flow of a fluid in the miniaturized valve position detecting switch for the pilot type selector valve. SOLUTION: This pilot type selector valve 1 with the valve position detecting switch is provided with an operator valve for controlling pilot signal pressure, a main valve element 3 driven by the pilot signal pressure, and the valve position detecting switch 2 for detecting the position of the main valve element 3. The valve position detecting switch 2 is provided with a permanent magnet 5 provided at the end part center of a piston 4 jointed to the main valve element 3; a magnetic sensor 7 for detecting the magnetic change generated by the movement of the permanent magnet 5; and a switch circuit 25 for outputting a valve position detection signal on the basis of the detection signal of the magnetic sensor 7. The permanent magnet 5, the magnetic sensor 7 and the switch circuit 25 are mounted in the selector valve 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pilot type switching valve with a valve position detecting switch capable of detecting the position of a main valve body driven by pilot signal pressure.

[0002]

2. Description of the Related Art Conventionally, pilot type switching valves used for pneumatic equipment have been used in various fields because they are low cost, labor-saving and can be automated. Further, in recent years, the size of pilot type switching valves has been reduced. Some systems that require reliability include a device that detects the position of the main valve element that operates to switch the flow paths. A pressure switch or a flow rate switch is used as this detection device.

The pressure switch and the flow rate switch detect the valve position of the pilot type switching valve by displaying an indicator for displaying the operation of the main valve body. For example, there is an indicator lamp shown in Japanese Utility Model Publication No. 1-30523. As shown in FIG. 10, in this indicator lamp, a button battery 108 is connected to one terminal of the lamp 103 in one chamber in a housing chamber 107 in a lamp body 102 having an operation display lamp 103. Are housed in contact with each other. On the other hand, the lamp body 102
The base 105 is provided with a pressure introducing hole 111 for introducing the fluid pressure of the fluid pressure device, and the non-conductive piston 112 driven by the fluid pressure from the pressure introducing hole 111 is
It is slidably fitted in the accommodation chamber 107. further,
The contact 1 is provided between the base 105 and a lamp support 104 made of a conductive material that is in electrical contact with the lamp 103.
14 are sandwiched.

Indicator lamp 1 having the above structure
In No. 01, when the piston 112 is mounted on the end of the pilot type switching valve and the piston 112 is pressed and slides by the fluid pressure flowing from the pressure introducing hole 111, the expanded diameter portion of the spring 109 contacts the contactor 114. Lamp 103 lights up. In this way, the operation of the main valve body is detected. Also, this indicator lamp is smaller than conventional pressure switches and flow switches.

There is known a so-called cylinder switch which detects the position of a piston that reciprocates inside a cylinder by utilizing a magnetic field generated by a magnet attached to the end of the piston. This cylinder switch attaches reed switches to the front and rear ends of the cylinder, and detects the magnetic field generated by the magnet attached to the end of the piston when the piston moves to the mounting position of each reed switch. The position of the piston is detected by opening and closing the reed switch and outputting an electric signal from the electric contact as a position detection signal.

Alternatively, by utilizing a magnetic sensor using a magnetoresistive element, the internal resistance value of the magnetoresistive element is changed by receiving a magnetic field generated by a magnet attached to the end of the piston, There is known a piston position detection device that detects the position of the piston by converting the change in the internal resistance value into an electric signal and outputting it as a position detection signal.

[0007]

However, the conventional pressure switch and flow rate switch have the following problems. That is, these pressure switches and flow switches
The problem is that the system itself becomes large because it is attached to the flow path outside the pilot type switching valve. In addition, since the pressure switch and the flow rate switch have a range of working pressure and working flow rate, there is also a problem that it is necessary to prepare several types according to the working range. Furthermore, since these pressure switches and flow rate switches only detect whether the flow path of the pilot type switching valve has been switched, it is possible to detect only two positions (ON / OFF detection) of the position of the main valve body. There are also problems.

A cylinder switch may be attached to the pilot type switching valve for detecting the position of the main valve body. However, since the stroke of the main valve body in the pilot type switching valve is only a few millimeters, the reed switch is mainly used. It is impossible to install at three places (even two places) within the range where the valve body slides.

Alternatively, when a magnetic sensor is used, two types of output voltage waveforms can be obtained depending on the mounting method. As the attachment method, a method of attaching a magnetic sensor which has been generally used in the past in a lying state (see FIG. 4A) and an attaching method of a magnetic sensor described in Japanese Utility Model Publication No. 7-4486 in an upright state are attached. Method (Fig. 3
(See (a)). The voltage range currently used as the switch output is the operating voltage range V1 or V2 shown in FIG. 3B or 4B.
When a voltage value above the reference voltage (hereinafter referred to as “reference voltage value”) is input within this operating voltage range, the transistor provided in the detection circuit is driven and a pulsed waveform is output. By doing so, the switch output is detected, but in the operating voltage range V1 or V2 shown in FIG. 3B or FIG. 4B, the sliding range of the magnet is limited in the pilot type switching valve. Only one or two points can be output, and three switch outputs cannot be taken. This is because, in the current operating voltage range, if three switch outputs, that is, three reference voltage values are taken due to the hysteresis of the magnetoresistive element and the hysteresis of the output voltage, there is a high possibility that it will overlap with the range of the adjacent switch output. This is because.

Therefore, the present invention has been made to solve the above-mentioned problems, and is a valve position detection switch of a miniaturized pilot type switching valve, which is a pilot type switching valve regardless of the fluid pressure and flow rate. An object of the present invention is to provide a pilot type switching valve with a valve position detection switch capable of detecting the valve positions of the valve up to three positions.

[0011]

A pilot type switching valve with a valve position detecting switch according to the present invention made to solve the above problems is operated by an operator valve for controlling pilot signal pressure and pilot signal pressure. In a pilot type switching valve with a valve position detection switch, which comprises a main valve body and a valve position detection switch for detecting the position of the main valve body, a permanent magnet provided at an end of a piston joined to the main valve body. And the piston fits and slides, and a magnetic sensor that detects the magnetic change generated by the movement of the permanent magnet outside the piston chamber where the pilot signal pressure is supplied, and the valve position based on the detection signal of the magnetic sensor. A switch circuit for outputting a detection signal is provided, and the permanent magnet, the magnetic sensor, and the switch circuit are mounted in the switching valve.

In this pilot type switching valve with a valve position detecting switch, a permanent magnet, a magnetic sensor and a switch circuit necessary for detecting the valve position are mounted in the switching valve. Therefore, the pilot type switching valve with the valve position detection switch can be made smaller than in the case where the components necessary for detecting the valve position are mounted outside the switching valve.

In the pilot type switching valve with the valve position detecting switch according to the present invention, it is desirable that the permanent magnet is provided at the center of the piston. This is because the permanent magnet can be moved in parallel with the magnetic sensor while keeping a constant distance, and thus the detection accuracy of the valve position can be improved.

Further, in the pilot type switching valve with the valve position detecting switch according to the present invention, the switch circuit can output the switch outputs at three points, and the reference voltages corresponding to the switch outputs at the three points are adjusted respectively. It is desirable to have a variable resistor for this. As a result, the magnitude of each reference voltage can be adjusted by each variable resistor, so the entire stroke of the main valve body (left end, middle, right end)
This is because it becomes possible to detect

In order to solve the above-mentioned problems, in the pilot type switching valve with a valve position detecting switch according to the present invention, the magnetic sensor forms a magnetically sensitive pattern in a zigzag shape on the substrate with a magnetic metal thin film. A resistance element,
The resistance of the magnetoresistive element is set so that the substrate is set upright so as to face the permanent magnet and the magnetic field generated by the permanent magnet acts on the magnetic sensitive pattern in the sliding range of the permanent magnet. It is desirable to limit from the position where the value is substantially the minimum to the position where the value is the maximum.

Further, in the pilot type switching valve with a valve position detecting switch according to the present invention, it is desirable that the magnetic sensor is covered with a magnetic shielding plate made of a magnetic material.

Here, as the magnetic shield, for example, a ferromagnetic iron plate or an amorphous metal plate can be used.

Further, it is desirable that the pilot type changeover valve with a valve position detecting switch according to the present invention perform a lamp display in conjunction with a signal output from the switch circuit.

According to the pilot type switching valve with the valve position detecting switch having the above structure, since the magnetic sensor is used, the position of the main valve body is detected regardless of the operating pressure and the operating flow rate of the pilot type switching valve. Therefore, it is possible to reduce the size because no extra circuit is required in the fluid passage. Further, by limiting the mounting method and the mounting position of the magnetic sensor, it is possible to take up to three position detection points of the main valve body.

Further, since the magnetic shield plate is provided, even if the pilot type switching valve is formed into a manifold, the magnetic field generated by the permanent magnets mounted on the adjacent pilot type switching valve is shielded, so that each magnetic field is shielded. The position of the main valve element can be accurately detected without the sensor malfunctioning.

Further, by displaying the lamp using the light emitting diode, the position of the main valve element can be surely detected only by visual inspection in addition to the electric signal.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a valve position detecting switch of a pilot type switching valve according to the present invention will be described in detail with reference to the accompanying drawings with reference to specific embodiments. FIG. 1 shows a pilot type switching valve with a valve position detecting switch according to a first embodiment of the present invention. FIG. 1 is a sectional view of a valve position detection switch of a pilot type switching valve. In FIG.
The valve position detection switch 2 includes a permanent magnet 5 buried in the center of the end of a piston 4 joined to the main valve body 3, and a magnetic sensor 7 installed outside the piston chamber 6 to which pilot signal pressure is supplied. , A switch circuit 25 for converting a change in resistance of the magnetic sensor 7 into an electric signal, and these components are mounted in the pilot type switching valve 1.

A permanent magnet 5 embedded in the end of the piston 4
Has a cylindrical shape with a diameter of 2 to 3 mm and is embedded in the center of the piston 4. Therefore, the permanent magnet 5 moves in parallel with the main valve body 3 with the magnetic sensor 7 at a constant distance.

The magnetic sensor 7 is a magnetoresistive element formed by etching a magnetic sensitive thin film formed of permalloy, which is a ferromagnetic metal, on a substrate into a zigzag pattern (see FIG. 2). Is. The magnetoresistive element has a property that its resistance value decreases when it receives a magnetic field at right angles to the longitudinal direction of the pattern line (y-axis direction in FIG. 2). The resistance value does not change. Therefore, as shown in FIG. 2, the magnetic sensing pattern 10 and the temperature compensation pattern 11
The magnetic sensitive pattern 10 formed of a magnetically sensitive thin film and having a phase difference of 90 degrees with each other has a high temperature dependency, and there is a practical problem as it is. further,
Ferromagnetic metals generally have the property that their internal resistance changes with temperature. Therefore, the internal resistance of the magnetic sensitive pattern 10 changes not only with the strength of the magnetic field but also with the ambient temperature. Therefore, the temperature compensation pattern 11 is created,
Compensates for changes in ambient temperature.

A method of mounting the above magnetic sensor will be described. Generally, as a method of mounting the magnetic sensor,
There are two methods shown in FIG. 3 (a) and FIG. 4 (a). As shown in FIG. 3 (a), there are vertical mounting in which the board is installed upright and horizontal mounting in which the board is laid down and installed as shown in FIG. 4 (a). The output voltage waveforms are different because, in the case of vertical mounting, when the permanent magnet 5 moves in the x direction, the temperature compensating pattern 11 also receives a magnetic field at a right angle to the longitudinal direction of the pattern line. The resistance change of 10 and the resistance change of the temperature compensation pattern 11 occur, and they are combined, and the waveform of the output voltage has a shape that swings to the plus side and the minus side, as shown in FIG. 3B. On the other hand, in the case of horizontal mounting, even if the permanent magnet 5 moves in the x direction,
Since the magnetic field is applied in the longitudinal direction of the pattern line of the temperature compensation pattern 11, the resistance of the temperature compensation pattern 11 does not change. Therefore, as shown in FIG. Has become.

In the above two types of mounting methods, when a magnetic sensor is used as the valve position detection switch of the pilot type switching valve, the range of movement of the permanent magnet is very small, so the voltage range that can be used as the switch output is The moving range of the magnet and the output voltage linearly correspond to each other, that is, the working voltage range V1 or V2 shown in FIG. 3B or 4B, both of which are substantially the same range. When the reference voltage value is input within this operating voltage range, the switch output can be detected by driving the transistor provided in the detection circuit to output a pulsed waveform. FIG. 3B or FIG.
In the operating voltage range V1 or V2 shown in (b), one point or two points can be output.

However, when the magnetic sensor is used as a valve position detecting switch of a pilot type switching valve, it cannot be applied to a 4-port 3-position valve or the like. That is, in order to detect the valve position of the 4-port 3-position valve, three switch outputs are required, but within the current operating voltage range, the switch output will be changed due to the hysteresis of the magnetoresistive element and the hysteresis of the output voltage. This is because if three points, that is, three reference voltage values are taken, there is a high possibility that they will overlap with the range of the adjacent switch output.

Therefore, by limiting the mounting method of the magnetic sensor 7 and the sliding range of the permanent magnet 5, the working voltage range V in which the output voltage is linearly output is as shown in FIG.
It can be 2-3 times the conventional voltage range used. Therefore, the reference voltage value, that is, the switch output can be reliably obtained up to three points. The sliding range of the permanent magnet 5 is
Since it can be arbitrarily changed by changing the combination of the pattern width of the magnetoresistive element and the total length and diameter of the permanent magnet, it is possible to cope with pilot type switching valves of various sizes. Further, the switch circuit shown in FIG. 7 detects the internal resistance of the magnetic sensor 7, converts the resistance value into a voltage value, and further outputs a signal as a switch output to the outside. This circuit configuration is the same as that used for cylinder switches in general, and the output is increased by one point, so that the light emitting diode emits light corresponding to the output signals of each three points. Built into the circuit.

Magnetic sensor 7 and permanent magnet 5 in this embodiment
Fig. 6 shows the relationship between the mounting position of and the output voltage at that time.
Will be explained. First, as shown in FIG. 6A, a state in which the air supply port P and the output port B communicate with each other, and the output port A and the exhaust port R communicate with each other (hereinafter, referred to as “first position”).
Then, the magnetic sensor 7 and the permanent magnet 4 are in the farthest state, and the output voltage value becomes a. Next, as shown in FIG. 6C, a state in which the air supply port P communicates with the output port A and the output port B communicates with the exhaust port R (hereinafter, referred to as “third position”).
Say. ), The magnetic sensor 7 and the permanent magnet 4 are in the state of being closest to each other, and the output voltage value is c. Finally, as shown in FIG. 6B, in the case of being located in the middle of the above two states, that is, in the all-port block state (hereinafter, referred to as “second position”), the output voltage value is b. Become. Since the output voltage value a is near the minimum value (negative value), the output voltage value b is near zero, and the output voltage value c is near the maximum value (plus value), the voltage difference at each point is It is equal to or more than the output voltage difference in the position detection switch used. Therefore, even if the switch outputs are obtained at the respective voltage values a, b, and c, the ranges of the switch outputs at the respective points do not overlap, and it is possible to reliably obtain the switch outputs at the three points. These voltage values a, b, c can be adjusted by a variable resistor provided in the switch main circuit 23 shown in FIG.

The operation of the valve position detecting switch of the pilot type switching valve according to the first embodiment described above will be described. First, at the first position, the decrease in the internal resistance value of the magnetic sensitive pattern 10 provided in the magnetic sensor 7 is small and the decrease in the internal resistance value of the temperature compensation pattern 11 is large, so the output voltage value becomes the minimum voltage value a. . Since the transistor 22 is driven by this voltage value a and the switch output A is output, it can be detected that the main valve 3 is in the first position.

Next, at the second position, since the permanent magnet 5 moves in the X direction in FIG. 6, it approaches the magnetic sensor 7. Then, the internal resistance value of the magnetic sensitive pattern 10 provided in the magnetic sensor 7 decreases and the internal resistance value of the temperature compensation pattern 11 increases, so that the output voltage value increases.
Then, the output voltage value becomes b at the second position. The transistor 21 is driven by this voltage value b, and the switch output B
Is output, it can be detected that the main valve body 3 is in the second position.

Finally, in the third position, the permanent magnet 5
Further moves in the X direction in FIG. 6 and approaches the magnetic sensor 7. Then, the internal resistance value of the magnetic sensitive pattern 10 provided in the magnetic sensor 7 further decreases, and the output voltage value further increases. Then, the output voltage value becomes c at the third position. Since the transistor 20 is driven by this voltage value c and the switch output C is output, it can be detected that the main valve body 3 is in the third position.

Further, as shown in FIG. 7, the switch circuit 25 is provided with a circuit for causing the light emitting diode to emit light in response to each switch output signal, so that the light emitting diode emits light when the main valve body 3 is in each position. Thus, the position of the main valve body 3 can be detected. For example, if the emission color of the light emitting diode is changed corresponding to each position, the position of the main valve body can be visually detected.

As described above, according to the pilot type switching valve with the valve position detecting switch according to the first embodiment, since the magnetic sensor is used, regardless of the operating pressure or the operating flow rate of the pilot type switching valve, The position of the main valve body can be detected. Moreover, since an extra circuit is not required in the fluid flow path, it is possible to reduce the size. Further, the permanent magnet 5, the magnetic sensor 7, and the switch circuit 25 are mounted in the pilot-type switching valve 1 to achieve downsizing.

Further, since the permanent magnet 5 is provided at the center of the piston 4, the permanent magnet 5 can be moved in parallel with the magnetic sensor 7 while keeping a constant distance, so that the main valve body 3 can be moved. The accuracy of position detection can be improved.

Further, since the switch circuit 25 can output the switch outputs at three points and is provided with variable resistors for adjusting the reference voltage values corresponding to the switch outputs at these three points, the respective reference voltages are provided. Since it is possible to adjust the size of each of the variable resistances, it is possible to detect the entire stroke (left end, middle, right end) of the main valve body 3.

Further, by limiting the mounting method and the mounting position of the magnetic sensor, it is possible to take three position detection points of the main valve body. Further, by displaying the lamp using the light emitting diode, the position of the main valve element can be surely detected only by visual inspection in addition to the electric signal.

Next, a pilot type switching valve with a valve position detecting switch according to the second embodiment will be described with reference to FIGS. FIG. 8 is a front view of the valve position detection switch according to the present embodiment, and FIG. 9 is a side view of the same. Here, the valve position detection switch of the first embodiment is, for example, 10 m
Although it can be mounted on a small m-sized solenoid valve, when a small switching valve equipped with a valve position detection switch is used as a manifold, the magnetic field generated by a permanent magnet mounted on an adjacent switching valve is used. The magnetic sensor may malfunction due to the influence of. For example, in FIG. 8, when focusing on the magnetic sensor 7b assuming that the magnetic shield 26 is not provided, the magnetic sensor 7b receives not only the magnetic field of the permanent magnet 5b but also the magnetic fields of the permanent magnets 5a and 5c. Malfunctions.

Therefore, in the valve position detecting switch of the pilot type switching valve according to the second embodiment, the magnetic sensor 7 is used.
Is covered with a magnetic shield plate 26. The mounting method and mounting position of the magnetic sensor and the permanent magnet are the same as those in the first embodiment.

Therefore, the magnetic shield 26 will be described with reference to FIGS. The magnetic shield plate 26 is attached only to one side of the pilot type switching valve, as shown in FIG. Although it may be mounted on both sides, the cost is increased, and the shielding effect is the same as in the case of mounting on one side. Therefore, in this embodiment, the magnetic shield plate is mounted on only one side. Further, as shown in FIG. 9, the size of the magnetic shield plate 26 is such that the width L1 and the length L3 of the magnetic shield plate 26 are the length L2 of the permanent magnet 5,
The mounting pitch distance between the permanent magnet 5 and the magnetic sensor 7 is L4.
Then, if it is determined so as to satisfy the relationship of L1 / L2> 2 and L3 / L4> 2, the influence of the magnetic field generated by the adjacent permanent magnets can be ignored. Further, since the thickness of the magnetic shield plate 26 may be 0.1 mm or more, a foil-shaped member may be attached instead of the iron plate or the like.

In the present embodiment, a ferromagnetic iron plate is used as the magnetic shield plate, but an amorphous metal plate can also be used. Even in this case, the size of the magnetic shield plate may satisfy the above conditions.

As described above, according to the pilot type switching valve with the valve position detecting switch according to the second embodiment, since it has the magnetic shield, it is adjacent even if the pilot type switching valve is manifolded. Since the magnetic field generated by the permanent magnet mounted on the pilot type switching valve is shielded, the position of the main valve element can be accurately detected without malfunctioning of each magnetic sensor.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various applications are possible. For example, although a magnetoresistive element is used as the magnetic sensor in the present embodiment, a Hall element or the like can be used.

[0044]

According to the pilot type switching valve with the valve position detecting switch of the present invention, the operator valve for controlling the pilot signal pressure, the main valve body driven by the pilot signal pressure, and the position of the main valve body are provided. In a pilot type switching valve with a valve position detection switch for detecting a valve position detection switch, a permanent magnet and a piston are fitted in and slid on a piston joined to the main valve body, and the pilot signal pressure is supplied. Since a magnetic sensor that detects a magnetic change generated by the movement of the permanent magnet and a switch circuit that outputs a valve position detection signal based on the detection signal of the magnetic sensor are provided outside the piston chamber The position of the main valve element can be detected regardless of the operating pressure and the operating flow rate of the shape switching valve, and no extra circuit is required in the fluid flow path, so downsizing is possible. Rukoto can. Also, a permanent magnet,
The magnetic sensor and the switch circuit are also miniaturized by being mounted in the switching valve.

Further, in the pilot type switching valve with the valve position detecting switch according to the present invention, since the permanent magnet is provided at the center of the piston, the permanent magnet is parallel to the magnetic sensor while maintaining a constant distance. Since it can be moved, the detection accuracy of the valve position can be improved.

Further, in the pilot type switching valve with the valve position detecting switch according to the present invention, the switch circuit can output the switch outputs at three points, and the reference voltage values corresponding to the switch outputs at the three points are adjusted respectively. Since the variable resistor for adjusting the reference voltage is provided, the magnitude of each reference voltage can be adjusted by each variable resistor, so that the entire stroke (left end, middle, right end) of the main valve body can be detected.

Furthermore, by limiting the mounting method and mounting position of the magnetic sensor, it is possible to take up to three position detection points of the main valve body. Also, since it has a magnetic shield,
Even if the pilot type switching valve is manifolded, the magnetic field generated by the permanent magnets installed in the adjacent pilot type switching valve is blocked, so each magnetic sensor does not malfunction and the position of the main valve element is accurately adjusted. Can be detected.

Further, by displaying the lamp using the light emitting diode, the position of the main valve element can be surely detected only by visual inspection in addition to the electric signal.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a pilot type switching valve with a valve position detection switch according to a first embodiment.

FIG. 2 is a conceptual diagram showing a configuration of a magnetic sensor according to the first embodiment.

FIG. 3 (a) is a magnetic sensor mounting method (vertical mounting).
FIG. 3B is a diagram showing the output voltage in the same mounting state.

[Fig. 4] (a) is a method of mounting the magnetic sensor (horizontal mounting)
FIG. 3B is a diagram showing the output voltage in the same mounting state.

FIG. 5 is a circuit diagram of an electric circuit that converts a resistance change of the magnetic sensor into a voltage value.

FIG. 6 is a diagram showing an output voltage output with respect to each positional relationship between a magnetic sensor and a permanent magnet.

FIG. 7 is a circuit diagram of a switch circuit according to the first embodiment.

FIG. 8 is a front view of a pilot type switching valve with a valve position detection switch according to a second embodiment.

FIG. 9 is a side view of a pilot type switching valve with a valve position detection switch according to a second embodiment.

FIG. 10 is a cross-sectional view of an indicator lamp that is a type of conventional pressure switch.

[Explanation of symbols]

1 Pilot type switching valve 2 valve position detection switch 3 Main valve body 4 pistons 5 permanent magnets 6 piston chamber 7 Magnetic sensor 25 switch circuit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Nobuo Niwa             250 Ojiki 2-chome, Komaki City, Aichi Prefecture             Inside the company F-term (reference) 3H065 AA04 BA01 BA07 BB11 BB18

Claims (3)

[Claims] 1. A pilot with a valve position detection switch, comprising an operator valve for controlling pilot signal pressure, a main valve body driven by the pilot signal pressure, and a valve position detection switch for detecting the position of the main valve body. In the shape switching valve, a permanent magnet provided at an end portion of a piston joined to the main valve body, and the permanent magnet provided outside the piston chamber where the piston is fitted and slides and the pilot signal pressure is supplied. A magnetic sensor that detects a magnetic change generated by the movement of the magnet, and a switch circuit that outputs a valve position detection signal based on a detection signal of the magnetic sensor are provided, the permanent magnet, the magnetic sensor, and the switch circuit. Is a pilot type switching valve with a valve position detection switch, which is mounted inside the switching valve. 2. The pilot type switching valve with a valve position detecting switch according to claim 1, wherein the permanent magnet is provided in a central portion of the piston. valve. 3. The pilot type switching valve with a valve position detection switch according to claim 1, wherein the switch circuit is capable of outputting three switch outputs and corresponds to the switch outputs of the three points. A pilot type switching valve with a valve position detection switch, characterized in that it is provided with variable resistors for adjusting respective reference voltages.