JP3141036B2 - Pilot operated switching valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pilot-operated switching valve for switching the main valve spool by controlling the discharge of pressure fluid in each pilot chamber formed at both ends of a main valve body by a pilot solenoid valve.

[0002]

2. Description of the Related Art Such a pilot-operated switching valve is disclosed in Japanese Patent Application Laid-Open No. Sho 62-4983. This is mounted on a main valve main body containing a main valve spool and mounted with a circuit board forming a passage for a pilot solenoid valve, and mounted on this circuit board and mounted with a pilot solenoid valve, A cover that covers the pilot solenoid valve is attached to the circuit board.

[0003]

However, Japanese Unexamined Patent Publication No.
In the configuration described in Japanese Patent Application Laid-Open No. 2-4983, the circuit board is fixed to the main valve body, the pilot solenoid valve is fixed to the circuit board, and the cover is fixed to the circuit board by fixing bolts. There is a problem that the valve cannot be easily assembled in many places. SUMMARY OF THE INVENTION The present invention solves such a problem, and a pilot-operated switching system in which a circuit board and a pilot solenoid valve can be fixedly mounted by mounting a cover with mounting bolts so that assembly of the valve can be simplified. It is intended to provide a valve.

[0004]

According to the present invention, there is provided a main valve body in which pilot chambers are formed at both ends of the main valve body so as to be switchably movable, and a main valve body formed on the main valve body and having a main body. A pilot passage for passing the pressure fluid flowing into and out of the pilot chamber for the switching movement, and a pilot solenoid valve mounted with two solenoids, respectively, and each pilot solenoid valve communicating with the pilot passage of the main valve body. A circuit board having an output hole and mounted on the main valve body, and a cover which is formed in a box shape with one side open, and whose open side is directed downward, is mounted on each solenoid body on the inner surface of the upper wall. Each solenoid body accommodates a movable core that is attracted to a fixed core by energizing a coil in an inner hole that forms an output chamber in which an output hole of a pilot solenoid valve is communicated with the circuit board when mounted on the circuit board. With cover A through hole is formed by opening the upper surface to be mounted and the lower surface to be mounted on the circuit board, and the cover of each solenoid body is placed with a discharge hole having a discharge valve seat around the opening to the output chamber provided in the fixed iron core. A communication groove is formed to penetrate the upper surface, and between the upper surface of each solenoid body and the inner surface of the upper wall of the cover placed thereon, a communication groove communicating the discharge hole and the through hole of each solenoid body is formed. On the circuit board, a through-hole of each solenoid body is formed as a communication passage communicating with a pilot discharge passage formed in the main valve body, and a periphery of an opening to each output chamber is mainly provided as a supply valve seat opened and closed by a movable iron core. A supply hole communicating with the pilot supply passage formed in the valve body is formed in each of the circuit boards, and the circuit board, the solenoids, and the cover are inserted through the cover, and the common valve is screwed to the main valve body by a common mounting bolt. Attached to the body That.

[0005]

According to the present invention, a circuit board is mounted on the main valve body, a solenoid body is mounted on the circuit board, and a cover is mounted on the solenoid body, and mounting bolts for inserting the cover are screwed into the main valve body. When worn, the pilot solenoid valve is formed by the circuit board and the solenoid body, and the circuit board, the solenoid body, and the cover are integrally attached to the main valve body.
The assembly of the valve is extremely simplified as compared with the conventional example.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a main valve main body formed of a body 2 and end covers 3 and 4. A spool 6 serving as a main valve body fitted to a sleeve 5 is accommodated therein so as to be freely movable in the axial direction. Are provided with pistons 7, 8 and form pilot chambers 9A, 9B between the pistons 7, 8 and the end covers 3, 4.

When the detent ball 10 is engaged with the detent groove 11A of the spool 6, the supply port 12 provided on the body 2 is connected to the output port 1 at the left switching position shown in FIG.
3, the output port 14 communicates with the discharge port 15, and the supply port 12 communicates with the output port 14 and the output port 13 communicates with the discharge port 16 at the right switching position where the detent ball 10 fits into the detent groove 11B. The pilot passage 17A, 17B communicating with the pilot chambers 9A, 9B, the pilot supply port 18 communicating with the supply port 12, and the pilot discharge passage 19 are opened in the upper surface 2A of the body 2. The lower end of the pilot discharge passage 19 is open to the lower surface 2B of the body 2.

The main valve body 1 is mounted and mounted on a manifold M as is well known. At this time, the supply port 12, the output ports 13, 14, the discharge ports 15, 16 and the pilot discharge passage 19 Are supply passages P, output passages A and B, and discharge passages E1 and E of the manifold M.
2. The pilot discharge passage PE communicates with each other. Here, although not shown, the supply passage P of the manifold M is connected to a fluid pressure source, the output passages A and B are connected to an actuator, and the discharge passages E1 and E2 are open to the atmosphere. At the same time, the pilot discharge passage PE is also opened to the atmosphere.

Reference numerals 20A and 20B denote pilot solenoid valves formed by a circuit board 21 mounted on the upper surface 2A of the body 2 and solenoids 22A and 22B mounted on the circuit board 21. The circuit board 21 forms recesses 23A and 23B on the upper surface,
The pilot passage 17 is provided in each of the recesses 23A and 23B.
Output holes 24A, 24B communicating with A, 17B are opened, and supply holes 26A, 26B are formed with supply valve seats 25A, 25B around the openings. Each of the supply holes 26A and 26B communicates with the pilot supply passage 18 of the body 2 via a communication groove 27 provided on the lower surface of the circuit board 21.

The solenoid members 22A and 22B have the same configuration, and will be described in detail with reference to the left solenoid member 22A in FIG. 1, and the corresponding portions of the right solenoid member 22B will be given the same numbers with the suffix B and will not be described. I do. Reference numeral 28A denotes a downwardly opened inner hole provided at the center of the solenoid body 22A.
A is vertically movably fitted. A fixed iron core 30A is arranged above the movable iron core 29A, and a coil 31A and a yoke 32A are arranged around the inner hole 28A and covered with a synthetic resin mold body 33A. The fixed iron core 30A has a discharge hole 36A formed around an opening of a discharge valve seat 35A which is opened and closed by a sheet body 34A provided at the upper end of the movable iron core 29A. The discharge hole 36A extends the fixed iron core 30A upward. And is open on the upper surface of the solenoid body 22A. Then, the solenoid body 22A is placed on the upper surface of the circuit board 21 so as to cover the inner hole 28A, and the inner hole 28A is
Together with A, an output chamber 37A of the pilot solenoid valve 20A accommodating the movable iron core 29A is formed, and a seat 38A for opening and closing the supply valve seat 25A is provided at the lower end of the movable iron core 29A. A spring 39A biases the movable iron core 29A to a normal position where the supply valve seat 25A is closed and the discharge valve seat 35A is opened when the coil 31A is not energized.

As shown in FIGS. 2 and 3, two bolt holes 40A and a through hole 41A which is a part of a discharge passage are opened through the upper and lower surfaces of the mold body 33A and penetrate through the solenoid body 22A. On the upper surface of the plate 21, FIGS.
As shown in FIG. 5, a communication groove 42 communicating with the openings of the through holes 41A and 41B on the lower surfaces of the solenoid bodies 22A and 22B is formed. The communication groove 42 is formed on the lower surface of the circuit board 21 and on the upper surface 2A of the body 2. Pilot discharge passage 1 opening in
The communication groove 43 communicates with the communication groove 9 through a through hole 44, and a communication passage 45 is formed by the communication grooves 42 and 43 and the through hole 44. The open side of the communication groove 42 is closed by a packing 46.

Numeral 47 denotes a box-shaped cover having an open side and an open side facing downward. The cover 47 covers the solenoids 22A and 22B and the circuit board 21 on the inner surface of the upper wall 48 so as to cover both solenoids 22A and 22B. As shown in FIG. 3, four mounting bolts 49 which are placed on the upper surface, pass through the cover 47, pass through the circuit board 21 through the bolt holes 40A, 40B of both solenoid bodies 22A, 22B, and are mounted on the upper surface 2A of the body 2. By screwing,
The cover 47 is integrally attached to the main valve main body 1 together with the circuit board 21 and the two solenoid bodies 22A and 22B. On the inner surface of the upper wall 48 of the cover 47, a communication groove 50A for communicating the upper end openings of the discharge hole 36A and the through hole 41A of the solenoid 22A with each other, the discharge hole 36B and the through hole 41B of the solenoid 22B. A communication groove 50 </ b> B that communicates the upper end openings with each other is provided.

Reference numerals 51A and 51B in FIG. 1 denote operation pins for manually switching the spool 6.
In FIG. 6, reference numeral 52 denotes a packing, and 53 denotes a positioning pin.

Next, the operation of this embodiment will be described. In the state shown in FIG. 1, both pilot solenoid valves 20A and 20B are in the normal position, and the pilot chambers 9A and 9B communicate with the pilot discharge passage 19 through the discharge holes 35A and 35B, the through holes 39A and 39B, and the communication passage 45. And the detent groove 1
The spool 6 is maintained at the left switching position by the engagement of the detent ball 10 with 1A, the supply port 12 is connected to the output port 13,
The output port 14 communicates with the discharge port 15. Here, when the coil 31A of the pilot solenoid valve 20A is energized, it is attracted by the fixed iron core 30A, the movable iron core 29A rises, the discharge valve seat 35A is closed, and the supply valve seat 25A is opened to switch to the operating position, and the pilot chamber 9A is switched. The pressure fluid from the supply hole 25A is introduced to the, and the spool 5 is switched to the right switching position. Next, when the energization of the coil 31A is cut off, the movable iron core 29A is returned by the spring 39A, and the pilot solenoid valve 20A again assumes the normal position as shown in FIG. 1 to discharge the pressure fluid in the pilot chamber 9A to the pilot discharge passage 19. The detent ball 10 engages with the detent groove 11B to keep the spool 6 at the right switching position. At this time, the supply port 12 is connected to the output port 14, and the output port 13 is connected to the discharge port 16.

Further, in this state, the pilot solenoid valve 20B
When the coil is energized to switch to the operating position, pressurized fluid is introduced into the pilot chamber 19B and the spool 6 switches to the left switching position as shown in FIG.
Is engaged with the detent groove 11A, and the pilot solenoid valve 20B
1 is switched to the normal position as shown in FIG. 1 and the spool 6 is kept at the left switching position.

Here, when a plurality of pilot operated switching valves are installed in the manifold M, the pressure in the pilot passage PE slightly increases due to discharge of the pressure fluid due to the switching operation of any one of the valves. However, when the spool 6 is held at the left or right switching position by engaging the detent ball 10 with the detent groove 11A or 11B, the pilot chambers 9A and 9B are connected to the same pilot discharge passage 19 by the pilot solenoid valves 20A and 20B. The pilot chambers 9A and 9B are brought into the same pressure by introducing the pressure of the pilot passage PE even if the pressure rises in the pilot passage PE as described above. There is no force to move the spool 6 out of the held switching position, and the switching position of the spool 6 is well maintained.

The circuit board 21 and the solenoid body 22
A, 22B, and the cover 47 are integrally attached to the main valve body 1 by screwing the common mounting bolt 49 to the body 2, so that the assembling operation can be easily performed, and formed along with this assembling. Pilot solenoid valve 2
0A and 20B are covered with a cover 47, and are protected from an external impact or the like. The circuit board 21 is connected to the pilot passages 17A and 17B in the main valve body 1 and the pilot supply passage 1.
8. Pilot discharge passage 19 and pilot solenoid valve 20
In addition to providing a flow path between the solenoid valves 20A and 20B, the solenoid valves 20A and 20B have supply valve seats 25A and 25B and recesses 23A and 23B.
A, 20B are formed, the number of parts is reduced, and the discharge holes 36A, 36 of the solenoid bodies 22A, 22B are formed.
The communication means between B and the through-holes 41A, 41B is formed as communication grooves 50A, 50B provided on the inner surface of the upper wall 48 of the cover 47 placed on the solenoid bodies 22A, 22B, and such communication with the solenoid bodies 22A, 22B. Combined with the elimination of the need to provide a unique end cover forming the means, a pilot operated directional control valve having a small shape is obtained.

In this embodiment, the communication passages 45 are formed as the communication grooves 42 on the upper surface of the circuit board 21 and the communication grooves 43 on the lower surface.
4, but without using such a communication groove 42 or a communication hole 44, a through hole communicating with each of the through holes 41A and 41B is formed in the circuit board 21 so as to communicate with a communication groove 43 on the lower surface thereof. You can also. The communication groove 27 for the supply fluid and the communication groove 43 for the discharge fluid provided on the lower surface of the circuit board 21 can be formed on the upper surface 2A of the body 2 if necessary. 22A, 22
The communication grooves 50A and 50B for communicating the discharge holes 36A and 36B of B with the through holes 41A and 41B are provided on the inner surface of the upper wall 48 of the cover 47, and the communication grooves 50A and 50B are placed on the covers 47 of the solenoid bodies 22A and 22B. It can also be provided on the upper surface.

[0019]

As described above, according to the present invention, the circuit board, the solenoid, and the cover are integrally attached to the main valve body by the common mounting bolts which are inserted through the cover and screwed to the main valve body. Assembly work can be simplified. The circuit board not only provides a flow path between the pilot solenoid valve and the pilot passage, the pilot supply passage, and the pilot discharge passage of the main valve body, but also forms the pilot solenoid valve together with the solenoid. The number of parts is reduced, and this, and the communication between the discharge hole and the through hole of each solenoid body, is caused by the mutual connection between the upper surface of each solenoid body and the inner surface of the upper wall of the cover placed there. In this case, it is not necessary to provide a member such as an end cover provided with a communication means between the discharge hole and the through hole in the solenoid body, so that a small pilot operated switching valve can be obtained. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention mounted on a manifold.

FIG. 2 is a partial cross-sectional view taken along line 100-100 in FIG.

FIG. 3 is a partial cross-sectional view taken along line 102-102 of FIG. 2;

FIG. 4 is a partial cross-sectional view taken along line 103-103 of FIG. 3;

FIG. 5 is a partial cross-sectional view taken along line 104-104 of FIG. 4;

FIG. 6 is a partial cross-sectional view taken along line 101-101 of FIG. 1;

[Explanation of symbols]

 1 Main valve body 6 Main valve body 9A, 9B pilot chamber 17A, 17B pilot passage 19 Pilot discharge passage 20A, 20B pilot solenoid valve 21 Circuit board 22A, 22B solenoid body 24A, 24B output hole 25A, 25B Supply valve seat 26A, 26B Supply hole 28A inner hole 29A, 29B movable iron core 30A fixed iron core 31A coil 35A discharge valve seat 36A, 36B discharge hole 37A, 37B output chamber 41A, 41B through hole 45 communication passage 47 cover 48 upper wall 49 mounting bolt 50A, 50B communication groove

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16K 27/00-27/12 F16K 31/06-31/11 F16K 31/36-31/42

Claims (1)

(57) [Claims] 1. A main valve body in which a pilot chamber is formed at both ends of a main chamber so as to be switchably movable, and a pressure formed in the main valve body to enter and exit the pilot chamber for switching the main valve body. A pilot passage through which fluid flows, and a solenoid valve mounted on each of the two solenoids, each having a pilot solenoid valve, and having an output hole for each pilot solenoid valve communicating with the pilot passage of the main valve body. It has a circuit board to be mounted and a cover which is in the form of a box open on one side and whose open side is downward, and which is mounted on each solenoid body on the inner surface of the upper wall, and each solenoid body is mounted on the circuit board. The output hole of the pilot solenoid valve is communicated with the circuit board by means of an installation. The inner hole that forms the output chamber communicates with the fixed core by energizing the coil in the inner hole, and the upper surface and the circuit board on which the cover is placed. And the lower surface An opening is formed to form a through hole, and a discharge hole having a discharge valve seat around the opening to the output chamber provided in the fixed iron core is formed to penetrate the upper surface on which the cover of each solenoid body is placed,
A communication groove is formed between the upper surface of each solenoid body and the inner surface of the upper wall of the cover mounted thereon to communicate the discharge hole and the through hole of each solenoid body. A pilot passage formed in the main valve main body as a supply valve seat which has a through hole of the solenoid body communicating with a pilot discharge passage formed in the main valve main body and which is opened and closed by a movable core around an opening to each output chamber. A supply hole communicating with the supply passage is formed in each circuit board, and the circuit board, each solenoid body and the cover are integrally attached to the main valve body by a common mounting bolt which is inserted through the cover and screwed to the main valve body. A pilot operated switching valve.