JP2000170940A - Switching valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely recognize the location of a moving body by directly visualizing the moving body. SOLUTION: A moving body 34 is stored within a moving body storing chamber 33 of a casing 29 so as to be movable. In the casing 29, a plurality of ports 37 to 39 communicating with the moving body storing chamber 33 are formed. The casing 29 is provided with a through hole 40 communicating with the moving body storing chamber 33. Within this through hole 40, a light transmissive view window 41 in close connection with the inner peripheral surface is provided. Therefore, the location of the moving body 34 can be surely recognized by directly viewing an upper side piston 26 of the moving body 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve for switching communication between ports by using pilot pressure.

[0002]

2. Description of the Related Art Generally, a spool accommodating portion is formed in a casing of a switching valve, and a spool is movably provided therein. A piston accommodating portion is formed at both ends of the spool accommodating portion in the casing, and a piston provided integrally with the spool is movably provided inside the piston accommodating portion. The piston defines a pressure action chamber in the piston accommodating chamber. The casing has a plurality of ports through which fluid flows in and out of the spool storage chamber. Then, when fluid is introduced into the pressure action chamber of the casing, pilot pressure acts on the piston in the same chamber to move the spool. This allows
Communication switching of each port is performed. With such a switching valve, it is necessary to confirm the position of the spool when performing a failure or maintenance.

Therefore, a spool position detecting device as disclosed in Japanese Utility Model Publication No. 1-35023 has been conventionally known. A fluid introduction chamber is formed in the case of the position detecting device, and the fluid introduction chamber is communicated with the pressure acting chamber of the spool accommodating section or the piston accommodating section via a communication hole. A button battery is housed in the fluid introduction chamber. One pole of the button battery is connected to one terminal of an indicator lamp provided on the case. A sliding body is movably accommodated in the fluid introduction chamber. Then, when a pilot pressure is applied to the pressure action chamber to move the spool, or when a fluid flows in the spool housing chamber, the pressure in the fluid introduction chamber is increased and the sliding body is moved. This movement connects the other electrode of the button battery and the other terminal of the display lamp. As a result, the display lamp is turned on, and the position of the spool can be known.

[0004]

However, in the conventional switching valve, the indicator lamp is turned on by moving the sliding body in the fluid introduction chamber of the position detecting device as described above, so that the moving position of the spool is indirectly determined. Have confirmed. Therefore, the type in which the fluid introduction chamber communicates with the pressure action chamber has the following disadvantages. That is, if the movement of the spool causes an operation failure such as a lock due to some cause and the pilot pressure acts even if the communication switching of each port is not performed, the display lamp is turned on. That is,
When a difference occurs between the position of the piston and the display of the indicator lamp, and a trouble occurs in the fluid pressure system including the switching valve, it takes time to identify a defective portion in the system. Further, when the pilot pressure is not acting on each pressure action chamber, none of the display lamps corresponding to each pressure action chamber is lit. Therefore, if the supply pressure to the spool accommodating portion is temporarily interrupted during maintenance or the like, the position of the spool cannot be grasped until pressure is supplied to the port again.

[0005] The type in which the fluid introduction chamber communicates with the spool accommodating section has the following disadvantages. That is,
If the pressure of the fluid flowing inside the spool housing is extremely low,
The sliding body in the fluid introduction chamber cannot be operated. Therefore, the display lamp cannot be reliably turned on. Therefore, the display lamp cannot be reliably turned on. Therefore, when a difference occurs between the position of the spool and the display of the display lamp, and a trouble occurs in the fluid pressure system including the switching valve, it takes time to identify a defective portion in the system. Further, the indicator lamp does not light when the fluid is not supplied to the spool housing.
For this reason, if the supply pressure to the spool accommodating section is temporarily interrupted during maintenance or the like, the position of the spool cannot be grasped before the pressure is supplied to the port again.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a switching valve capable of reliably grasping the position of a moving body by directly observing the moving body. To provide.

[0007]

According to a first aspect of the present invention, there is provided a casing having a moving body accommodating chamber therein, a moving body movably accommodated in the moving body accommodating chamber, and provided in the casing; A plurality of ports communicating with the moving body accommodating chamber, wherein the communication of the ports is switched by moving the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing. The gist of the present invention is that the switching valve is a switching valve in which a through-hole communicating with the moving body housing chamber is provided in the casing, and a light-transmitting member for closing the through-hole is provided in the through-hole.

[0010] According to this configuration, the moving body in the moving body housing chamber can be directly viewed from the through-hole through the light transmitting member, so that the position of the moving body can be confirmed.

According to a second aspect of the present invention, in the switching valve according to the first aspect, an outer end side opening of the through hole is formed on an end face of a casing corresponding to a moving direction of the moving body. That is the gist.

According to this configuration, it is possible to confirm the position of the moving body by visually checking whether the moving body has approached or moved away from the viewer.
According to a third aspect of the present invention, there is provided a casing having a moving body housing chamber therein, a moving body movably housed in the moving body housing chamber, and a plurality of casings provided in the casing and communicating with the moving body housing chamber. A switching valve for moving the moving body by means of a pilot pressure acting in a pressure action chamber defined by the moving body in the casing and switching communication between the ports, wherein the moving to the casing is performed. A through hole communicating with the body receiving chamber is provided, and an inner end side opening of the through hole is formed in a region of the moving body receiving chamber which is not affected by the pilot pressure and the pressure of the fluid flowing through the port. Is the gist. According to this configuration, since the moving body in the moving body housing chamber can be directly viewed through the through hole, the position of the moving body can be confirmed. Further, since the through-hole is formed in a region where the pressure of the pilot pressure does not affect, it is difficult to reduce the hermeticity of the casing and the operability of the moving body. or,
Since the through-hole is formed in a region where the pressure of the fluid flowing through the port does not affect, there is no fear that the fluid leaks out of the casing through the through-hole.

[0011]

An embodiment of the present invention will be described below in detail with reference to the drawings. As shown in FIGS. 1 and 2, the solenoid valve manifold 1 as a switching valve is composed of two parts: a pilot solenoid valve 2 and a manifold block 3. A plurality of pilot solenoid valves 2 are connected to the left end face 3a of the manifold block 3.

On one side end surface of the manifold block 3, a cylinder connection port group having a cylinder A port 5 and a cylinder B port 6 as a set is arranged. or,
A supply P port 7 for supplying air (air) as a fluid is provided through the manifold block 3. The piping for supplying and discharging air to and from the supply P port 7
It is configured to be connected to a not-shown rear end face.
Cylinder A port 5 is connected to passage 10 and cylinder B port 6
Is in communication with the flow path 11 and the supply P port 7 is in communication with the flow path 12. In addition, these flow paths 10, 11, 12
Both are open at the left end surface 3a of the manifold block 3.

The solenoid valve 2 includes a main valve section 21 and a manual switching section 2.
2 and a pilot valve portion 23.
The pilot valve section 23 is arranged in parallel with the main valve section 21 via a manual switching section 22. Pilot valve part 23
Has solenoids 28a and 28b.

The casing 29 of the main valve portion 21 includes a spool housing portion 30 made of metal and piston housing portions 31 and 32 made of synthetic resin. The piston accommodating portions 31 and 32 are disposed at both upper and lower ends of the spool accommodating portion 30. A moving body accommodating chamber 33 is formed in the casing 29, in which a moving body 34 is slidably accommodated along its own longitudinal direction.

The moving body 34 includes a spool 24 and circular pistons 25 provided at both ends of the spool 24.
26. An insertion hole 30a extending in the longitudinal direction is formed in the spool accommodating portion 30, and the spool 24 is slidably accommodated therein. The packing 50a provided on the outer periphery of the spool 24 allows the port 50
The air flowing in a to 50e does not leak to the outside.

The pistons 25, 26 are housed in pressure action chambers 31a, 32a formed in the piston housings 31, 32, respectively. The outer peripheral surface of each piston 25, 26
The inner surfaces of the pressure action chambers 31a and 32a are slidable. In this embodiment, the moving body accommodating chamber 33 includes the insertion hole 30a and the pressure action chambers 31a, 31 at both ends in the longitudinal direction.
2a. Also, each piston 25, 26
Are provided with annular packings 35 and 36 extending along the circumferential direction thereof. Double packing 3
The outer circumferences of the pressure working chambers 5 and 36 are slidable on the inner surfaces of the pressure action chambers 31a and 32a. And this packing 35,
36 prevents the air in each of the pressure action chambers 31a and 32a from leaking.

The three ports 37, 38, and 39 communicating with the moving body accommodating chamber 33 are all open at the right end face 29a of the casing 29. Each of the ports 37,
The opening portions 38 and 39 match the opening portions of the flow paths 10, 11 and 12 on the manifold block 3 side. or,
The manual switching section 22 and the main valve section 21 are formed with a pilot pressure introduction flow path 27 that branches off midway. One of them, which is divided into the lower side, is communicated with the pilot valve section 23 and the lower pressure action chamber 31a of the main valve section 21 via the manual switching section 22. The other one, which is divided into the upper side, communicates with the pilot valve section 23 and the upper pressure action chamber 32 a of the main valve section 21 via the manual switching section 22.

A pilot pressure is introduced from the A port of the pilot valve portion 23 into the lower pressure action chamber 31a. When the pilot pressure acts in the lower pressure action chamber 31a by the excitation of the lower solenoid 28a, FIG.
, The spool 24 and the pistons 25, 2
6 is pressed upward. The pilot pressure is introduced from the R port of the pilot valve portion 23 into the upper pressure action chamber 32a. When the pilot pressure acts on the upper pressure action chamber 32a by the excitation of the upper solenoid 28b, the spool 24 and the pistons 25 and 26 are pressed downward as shown in FIG.

Next, the main part of this embodiment will be described. As shown in FIG.
A circular through-hole 40 is formed in the upper part of the cylinder 2 and communicates with the upper pressure action chamber 32a from outside. The opening on the inner end side of the through hole 40 is the upper pressure action chamber 32
a. The outer end side opening of the through hole 40 is formed outside. The axis of the through hole 40 is aligned with the spool 24.
Axis. In other words, the axis of the through hole 40 coincides with the center of the upper piston 26.

The through hole 40 is closed by a viewing window 41 as a light transmitting member having a columnar shape. Through this viewing window 41, the position of the upper piston 26 in the upper pressure action chamber 32a can be visually checked. The viewing window 41 is made of a transparent synthetic resin material such as acrylic.

An annular engaging groove 42 is formed on the outer peripheral surface of the viewing window 41, and an O-ring 43 is fitted in the engaging groove 42. The outer peripheral surface of this O-ring 43
0 is pressed against the inner peripheral surface. By this pressure contact, the air introduced into the upper pressure action chamber 32a is prevented from leaking to the outside, and the airtightness in the upper pressure action chamber 32a is ensured. A pair of spring pins 44 is provided on the outer peripheral surface of the viewing window 41 outside the O-ring 43. The viewing window 41 is formed by the spring pin 44 in the through hole 4.
It is attached to 0.

The inner end face of the viewing window 41 is
It is flush with the inner wall. The outer end surface of the viewing window 41 is flush with the upper end surface of the upper piston accommodating portion 32. The axis of the viewing window 41 is arranged at a position coinciding with the axis of the spool 24. In other words, the axis of the viewing window 41 is arranged at a position coinciding with the center of the upper piston 26.

Next, the operation of the solenoid valve manifold 1 of this embodiment will be described. In the state of FIG. With the air supplied, the lower solenoid 28a
Is excited, the air is introduced into the lower pressure action chamber 31a of the lower piston 25 via the pilot valve section 23, the manual switching section 22, and the pilot pressure introduction channel 27.
Then, when the lower piston 25 is pressed by the pressure of the air, the spool 24 moves upward (the position shown in FIG. 2). By this movement, the supply P port 7 and the cylinder A
The communication with the port 5 is established. Therefore, air is supplied to the cylinder A port 5 side.

Conversely, the lower solenoid 28a is demagnetized,
When the upper solenoid 28b is excited, air is not introduced into the lower pressure action chamber 31a and the upper pressure action chamber 3
2a. Then, when the upper piston 25 is pressed by the pressure of the air, the spool 24 moves downward (the position shown in FIG. 1). By this movement, the supply P port 7 and the cylinder B port 6 communicate. Therefore, air is supplied to the cylinder B port 6 side.

In order to confirm the position of the moving body 34, the upper surface of the upper piston 26 is visually checked through the through hole 40 through the viewing window 41. As a result of visual observation, when the upper piston 26 is on the near side (the upper side in FIG. 1), the moving body 34 is located at the upper stroke end. Conversely, when the upper piston 26 is on the depth side (the lower side in FIG. 1), the moving body 34 is located at the lower stroke end.

Therefore, according to this embodiment, the following effects can be obtained. (1) The moving body 3 is placed in the moving body accommodating chamber 33 of the casing 29.
4 are movably accommodated. The casing 29 is provided with a plurality of ports 37 to 39 communicating with the moving body housing chamber 33. The casing 29 is provided with a through-hole 40 communicating with the moving body accommodating chamber 33, and in this through-hole 40 is provided a light-transmissive viewing window 41 which is in close contact with the inner peripheral surface thereof. For this reason, the upper piston 26 of the moving body 34
Can be reliably grasped by directly observing the position of the moving body 34. Therefore, even if the movement of the movable body 34 is locked, air is not supplied to the pressure action chambers 31a and 32a, or the spool 24 malfunctions, there is no problem anywhere. Can be found in a short time. In addition, when air is supplied to the cylinder supply P port 7, it is possible to know in advance whether air comes out to either the cylinder A port 5 or the cylinder B port 6, so that the home position after the maintenance of the equipment is inspected. The return confirmation and start-up time can be shortened.

(2) The outer end side opening of the through hole 40 is formed at the end face of the casing corresponding to the moving direction of the moving body 34, that is, at the upper end face of the casing 29. That is, the through hole 40
Is arranged on the axis of the moving body 34. Therefore, the entire upper piston 26 in the upper pressure action chamber 32a can be seen. As a result, the position of the moving body 34 can be more easily grasped.

(3) The viewing window 41 is attached to the through hole 40 by engaging a pair of spring pins 44 with the circumferential groove of the viewing window 41. For this reason, the viewing window 41 can be attached at low cost as compared with, for example, a configuration in which the viewing window 41 having a screw on the outer peripheral surface is screwed into the through hole 40.

(4) The outer end surface of the viewing window 41 is the casing 2
9 does not protrude from the outer surface. Therefore, it is possible to reduce the size of the entire solenoid valve manifold 1. At the same time, the appearance quality of the solenoid valve manifold 1 can be improved.

(5) The position of the moving body 34 can be surely grasped without projecting a part of the pistons 25, 26 from the insides of the respective pressure action chambers 31a, 32a.
Therefore, the pistons 25 and 26 and the respective piston housings 31 and
32, there is no sliding part between the piston 2
It is possible to prevent the outer peripheral surfaces of the fifth and 26th surfaces from being worn, and to be maintenance-free. (Second Embodiment) Next, a second embodiment of the present invention will be described.
The following description focuses on the differences from the first embodiment.

In the second embodiment, as shown in FIG. 4, pilot valves 23 are provided at both left and right ends of a casing 29, and solenoid valves are housed in each pilot valve 23. . A moving body housing chamber 33 extending in the left-right direction is formed in the casing 29. The lower end surface 29a of the casing 29 has five ports 50a to 50e communicating with the insertion holes 30a of the moving body housing chamber 33.

At the left and right ends of the spool accommodating portion 30 in the casing 29, vertically extending grooves 52,
53 are formed. Each of the grooves 52 and 53 is a spool 2
4 above. Then, each groove 52, 53
Are enclosed by the inner surface of the spool housing portion 30 and the side surface of the spool accommodating portion 30 facing the groove portions 52, 53, so that the through holes 55, 56
Are formed. Each of the through holes 55 and 56 is provided in the moving object accommodation room 3.
3 and is communicated with the insertion hole 30a of the spool 24.

The outer ends of the through holes 55 and 56 are formed on the upper end surface of the spool housing 30. Each through hole 5
The inner end openings of the fifth and 56 are formed in a region where the pilot pressure and the pressure of the air flowing through the ports 50a to 50e are not affected in the moving body housing chamber 33. That is, the inner end side openings of the through holes 55 and 56 are arranged at positions facing the outer peripheral surface of the spool 24. In this embodiment, the pressure in the moving body housing chamber 33 in which the through holes 55 and 56 are provided is atmospheric pressure.

Marks 57, 58 for indicating the position of the moving body 34 are colored on the outer peripheral surfaces of both ends of the spool 24. In this embodiment, each mark 57, 5
The color of No. 8 is red (the portion indicated by the dotted line in FIG. 4).
Then, when the moving body 34 moves to one of the left and right sides, one of the marks 57 and 58 becomes one of the through holes 5.
It is arranged at a position facing 5,56.

Next, the operation of the solenoid valve manifold 1 of this embodiment will be described. To confirm the position of the moving body 34, the outer peripheral surface of the spool 24 is visually observed through the respective through holes 55 and 56. That is, as a result of visual observation, the left through-hole 5
When the mark 57 is confirmed in 5, the moving body 34 is located at the right stroke end. On the contrary, when the mark 58 is confirmed in the right through-hole 55,
The moving body 34 is located at the left stroke end. Further, the marks 57, 5 are formed from the two through holes 55, 56.
If a part of 8 is visible, it means that the moving body 34 is located in the middle of both left and right stroke ends.
In addition, a through hole 5 is provided in an area where the influence of the pilot pressure is not exerted.
Since the members 5 and 56 are formed, the airtightness of the casing 29 and the operability of the moving body 34 are not easily reduced. In addition, through hole 5
Since the holes 5 and 56 are formed in a region where the pressure of the air flowing through the ports 50a to 50e does not affect the air, there is no fear that the air leaks out of the casing 29 through the through holes 55 and 56.

Therefore, the second embodiment has the following effects. (1) The inner ends of the through holes 55 and 56 are connected to the pilot pressure and the ports 50a to 50e in the moving body housing chamber 33.
It is formed in a region that is not affected by the pressure of the air flowing inside. Therefore, the position of the moving body 34 can be reliably grasped by directly viewing the spool 24.

(2) Since the through-holes 55 and 56 are formed in the casing 29, the cost is reduced. (3) The marks 57,
58 is colored. Therefore, by checking whether or not the marks 57 and 58 are present through the through holes 55 and 56, the position of the moving body 34 can be more easily grasped.

The embodiment of the present invention may be modified as follows. As shown in FIG. 5, a cover 65 for covering the outer end surface of the viewing window 41 is provided on the outer end surface of the piston housing portion 32. A locking projection 65a is provided at the base end of the cover 65.
Is formed, and the locking projection 65a is
Is attached to a mounting groove 66 formed at a lower portion of the mounting member. As a result, the cover 65 is fixed to the piston housing portion 32. A thin hinge 67 made of a flexible material is formed at the base end of the cover 65, and the cover 65 is rotatable around the thin hinge 67. An engagement protrusion 65 b is formed at the tip of the cover 65, and the engagement protrusion 65 b can be engaged with an engagement recess 68 formed on the left outer end surface of the piston accommodating portion 32.

When the moving body 34 is viewed through the viewing window 41, the engagement between the engaging recess 68 and the engaging protrusion 65b is released, and the cover 65 is moved rightward (clockwise in FIG. 5). Rotate. Thereby, the outer end face of the viewing window 41 is exposed to the outside. When the moving body 34 is not viewed, the cover 65 is rotated to the left (counterclockwise direction in FIG. 5) so that the engagement protrusion 65b is engaged with the engagement recess 68. By this engagement, the outer end surface of the viewing window 41 is covered by the cover 56. Therefore, since the viewing window 41 is exposed to the outside only when the viewing window 41 is used, it is possible to prevent dust or the like from adhering to the outer end surface of the viewing window 41.

In the first embodiment, the viewing window 41 is made of acrylic, but other synthetic resin materials may be used.
You may change to nylon, polycarbonate, etc. or,
In order to be able to see the piston 26 enlarged,
The shape of the viewing window 41 may be changed.

In the first embodiment, the viewing window 41 is attached to the through hole 40 by the spring pin 44, but the viewing window 41 may be fixed by an adhesive. In the first embodiment, the through hole 40 is provided in the upper piston housing portion 32. However, the through hole 40 may be provided in the lower piston housing portion 31, or the upper and lower piston housing portions 31, 32.

In the first embodiment, the entire piston accommodating portion 32 may be formed of a light transmissive material. According to this configuration, not only can the upper piston 26 be seen, but also the upper part of the spool 24 can be seen.

In the first embodiment, the outer end surface of the viewing window 41 is flush with the outer wall surface of the piston accommodating portion 32. Alternatively, the outer end surface of the viewing window 41 may be provided inside or outside the outer wall surface of the piston housing portion 32.

In the first embodiment, the through hole 40 is closed by providing the viewing window 41 inside the through hole 40.
Alternatively, plate-like viewing windows 41 may be provided at both inner and outer ends of the through hole 40 so that the inside of the through hole 40 is hollow.

In the second embodiment, each mark 57,
The color of 58 is red, but it is also possible to change it to a color such as blue, green, fluorescent color and the like. Also, each of the through holes 55 and 56
May be colored differently from the marks 57 and 58 on the inner surface of the. With this configuration, the marks 57 and 58 are more easily seen.

In the second embodiment, the through holes 55,
56 may be closed by a light transmitting member. Next, in addition to the technical ideas described in the claims, technical ideas grasped by the above-described embodiments are listed below together with their effects.

(1) The switching valve according to claim 1 or 2, wherein the light-transmitting member is disposed on an axis of a moving body. According to this configuration, the position of the moving body can be more easily grasped.

(2) The switching valve according to any one of (1), (2), and (1), wherein an outer end surface of the light transmitting member is flush with an outer surface of the casing. According to this configuration, the appearance quality of the switching valve can be improved.

(3) The switching valve according to any one of (1), (2), (1) and (2), wherein the light transmitting member is attached to the through hole by a spring pin. According to this configuration, the light transmissive member can be attached at low cost.

(4) The switching valve according to any one of (1) to (3), wherein the outer end surface of the light transmitting member is located inside the end surface of the casing. According to this configuration, it is possible to prevent an increase in the size of the light transmitting member.

(5) The switching valve according to any one of claims 1, 2, and (1) to (4), further comprising a cover capable of covering an outer end surface of the light transmitting member. According to this configuration, since the outer end surface of the light transmissive member can be prevented from being stained by dust or the like, a good view can be secured.

(6) A mark for indicating the position of the moving body 34 is provided on at least one of the moving body and the casing. The switching valve according to (1). According to this configuration,
The position of the moving body can be more easily grasped.

(7) A casing having a moving body accommodating chamber therein, a moving body movably accommodated in the moving body accommodating chamber, and a plurality of ports provided in the casing and communicating with the moving body accommodating chamber. A switching valve that moves the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports, wherein the casing includes the moving body. A switching valve with a translucent part for viewing.
According to this configuration, the position of the moving body can be reliably grasped.

(8) A casing having a moving body housing chamber therein, a moving body movably housed in the moving body housing chamber, and a plurality of ports provided in the casing and communicating with the moving body housing chamber. A switching valve that moves the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports, wherein the casing includes the moving body. A switching valve with a viewing window for viewing.
According to this configuration, the position of the moving body can be reliably grasped.

(9) A casing having a moving body accommodating chamber therein, a moving body movably accommodated in the moving body accommodating chamber, and a plurality of ports provided in the casing and communicating with the moving body accommodating chamber. A switching valve that moves the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports, wherein the moving body housing chamber is provided in the casing. A switching valve provided with a through hole communicating with the movable member, and an opening at the inner end side of the through hole is formed in a region where thrust is not applied to the moving body. According to this configuration, the position of the moving body can be reliably grasped, and the moving body can be moved smoothly.

(10) A casing having a moving body accommodating chamber therein, a moving body movably accommodated in the moving body accommodating chamber, and a plurality of ports provided in the casing and communicating with the moving body accommodating chamber. A switching valve that moves the moving body by a pilot pressure acting in the pressure action chamber defined by the moving body in the casing and switches communication between the ports, wherein a transparent port communicating with the moving body housing chamber is provided. A switching valve provided with a hole so that the through hole communicates with a region where the pressure in the moving object housing chamber is atmospheric pressure.
According to this configuration, the position of the moving body can be reliably grasped, and the moving body can be moved smoothly.

(11) A casing having a moving body housing chamber therein, a moving body movably housed in the moving body housing chamber, and a plurality of ports provided in the casing and communicating with the moving body housing chamber. A switching valve that moves the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports, wherein the moving body is spooled and the spool is A pair of pistons provided at both ends of the moving body, a pair of through holes communicating with the moving body housing chamber are provided, and the inner end side opening of each through hole is arranged at a position communicating with each piston of the moving body. Switching valve. According to this configuration, the position of the moving body can be reliably grasped, and the operability of the moving body can be prevented from being reduced.

[0058]

According to the first aspect of the present invention, the position of the moving body can be reliably grasped by directly viewing the moving body.

According to the second aspect of the present invention, the position of the moving body can be more easily and reliably grasped. According to the third aspect of the present invention, the position of the moving body can be reliably grasped with a simple configuration and without adversely affecting the operability of the moving body.

[Brief description of the drawings]

FIG. 1 is a sectional view of a solenoid valve manifold according to a first embodiment, in which a moving body is moved downward.

FIG. 2 is a cross-sectional view of the solenoid valve manifold in which the moving body is moved upward.

FIG. 3 is an enlarged sectional view of a main part, similarly.

FIG. 4 is a sectional view showing a part of a solenoid valve manifold according to a second embodiment.

FIG. 5 is a cross-sectional view of a solenoid valve manifold showing another embodiment.

[Explanation of symbols]

Reference numeral 24: spool, 25: left piston, 26: right piston, 29: casing, 31a: left pressure action chamber, 3
2a: Right pressure action chamber, 33: Moving body housing chamber, 34: Moving body, 37-39: Port, 40, 55, 56: Through-hole,
41 ... viewing window (light transmitting member).

Continuation of the front page (72) Inventor Masahiro Tada 3005, Hayasaki, Kita-gaiyama, Komaki-shi, Aichi F-term (reference) in KK Corporation 3H051 AA10 BB10 CC11 CC17 DD09 FF07 3H056 AA09 BB44 CA02 CD02 CE03 DD10 GG04 GG12

Claims (3)

[Claims] 1. A casing having a moving body housing chamber therein, a moving body movably housed in the moving body housing chamber, and a plurality of ports provided in the casing and communicating with the moving body housing chamber. A switching valve configured to move the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports; A switching valve provided with a communicating hole, and a light transmitting member for closing the communicating hole. 2. The switching valve according to claim 1, wherein an outer end opening of the through hole is formed on an end face of a casing corresponding to a moving direction of the moving body. 3. A casing having a moving body accommodating chamber therein, a moving body movably accommodated in the moving body accommodating chamber, and a plurality of ports provided in the casing and communicating with the moving body accommodating chamber. A switching valve configured to move the moving body by a pilot pressure acting in a pressure action chamber defined by the moving body in the casing to switch communication between the ports; A switching valve provided with a communicating hole, and an opening at the inner end side of the communicating hole formed in a region of the moving body accommodating chamber which is not affected by the pilot pressure and the pressure of the fluid flowing through the port.