JPH07279907A - Pressure reducing valve type pilot valve - Google Patents

Abstract

PURPOSE:To decrease constituent parts, so as to reduce manufacturing costs in forming a ball joint for supporting an operating lever so as to be oscillated, and capable of preventing the rotation of the operating lover in the oscillating operation. CONSTITUTION:A spherical protrusion 37 is integrally formed on a cam 34 for constituting an operating lever 32, and a spherical surface part 37a and a circular-arc surface part 37b respectively having different radius of curvature are formed on the outer periphery of the spherical protrusion 37. And a fitting recessed part 42 composed of a circular arc-shaped recessed part with which the spherical surface part 37a of the spherical protrusion 37 is to be engaged and a flat surface part with which the circular-arc surface part 37b is to be engaged is provided on a screw member 39 to be screwed to a casing 1. And, a ball joint 43 including a rotation preventing part is constituted by fitting the spherical protrusion 37 into the fitting recessed part 42 while engaging the circular-arc surface part 37b with the flat surface part. Thereby, constituent parts of the ball joint 43 can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-reducing valve type pilot valve suitable for use in, for example, switching control of a directional control valve or the like in a main circuit. The present invention relates to a pressure reducing valve type pilot valve made possible.

[0002]

2. Description of the Related Art In recent years, construction machines, civil engineering machines, and the like have become larger, faster, and have higher performance, which complicates hydraulic circuits and increases the flow rate of pressure oil flowing through the hydraulic circuits. Due to the tendency, a large capacity hydraulic pump is used, and the direction switching valve and the like are also enlarged. In order to easily and smoothly perform the switching control of this kind of directional control valve and the tilt control of the variable displacement pump, a hydraulic pilot circuit for performing these controls using a pressure reducing valve type pilot valve is widely adopted. There is.

A hydraulic excavator is a typical construction machine using the pressure reducing valve type pilot valve. An ordinary hydraulic excavator has operation levers at the left and right positions of the driver's seat, for example, the left operation lever operates the arm cylinder (extend / contract operation) and the swing motor (forward / reverse operation), and the right operation lever operates the boom. Cylinder (expanding and contracting)
And a bucket cylinder (extending and contracting motion).

Therefore, each of the left and right pressure reducing valve type pilot valves is composed of four pressure reducing valve portions.

As such a pressure reducing valve type pilot valve according to the prior art, for example, Japanese Utility Model Laid-Open No. 2-140004,
There is a pressure reducing valve type pilot valve of the type proposed in Japanese Utility Model Laid-Open No. 3-59502. Hereinafter, the pressure reducing valve type pilot valve will be described with reference to FIGS. 7 to 10.

In the figure, reference numeral 1 denotes a casing which constitutes the main body of a pressure reducing valve type pilot valve, and four pressure reducing valve portions 2A, 2B, 2C and 2 having the same structure are provided in the casing 1.
D has been realized. In the following, each pressure reducing valve section 2A, 2
The constituent elements corresponding to B, 2C, and 2D include subscripts A, B, and
It is shown with C and D attached. Further, in FIG. 9, 2A and 2B of the pressure reducing valve units 2A to 2D are shown.

Here, the casing 1 has a pump port 3 into which pressure oil from a hydraulic pump P flows, and a tank T.
And a spring chamber 5 that is in constant communication with the tank port 4, and pusher guide holes 6A and 6B that are formed in the casing 1 at 90-degree intervals in the circumferential direction and open in the spring chamber 5. 6C and 6D (however, 6C and 6D are not shown) are provided on the lower end side of the casing 1 so as to be coaxial with the pusher guide holes 6A to 6D and are connected to the directional control valves V1 and V2. Output ports 7A, 7
B, 7C, 7D (however, for 7C and 7D, see FIG. 8),
The spring chamber 5 and the output ports 7 are arranged so that the output ports 7A to 7D communicate with the pump port 3 and the tank port 4.
Spool guide holes 8A, 8 formed between A and 7D
B, 8C and 8D (however, 8C and 8D are not shown) are provided.

On the other hand, among the pressure reducing valve sections 2A to 2D,
The pair of pressure reducing valve portions 2A and 2B are provided with spools 9A and
9B, pushers 11A and 11B, and return spring 13
It is mainly composed of A and 13B and setting springs 15A and 15B. Since the pressure reducing valve units 2A and 2B have the same structure, only the configuration of the pressure reducing valve unit 2A will be described below.

Reference numeral 9A designates a spool which is slidably displaceable in the spool guide hole 8A, and the output port 7A is provided in the spool 9A in accordance with the position of the spool 9A.
A flow path 10A communicating with either the pump port 3 or the tank port 4 is formed in the axial direction.

A pusher 11A is slidably inserted into the pusher guide hole 6A and has a spherical upper end.
The pusher 11A is retained by an upper lid 12 provided on the upper end side of the casing 1.

Reference numeral 13A designates a return spring disposed in the spring chamber 5. The return spring 13A rotates the pusher 11A via a spring receiving member 14A so as to return the pusher 11A to the initial position shown in the figure. Always urges upward.

Reference numeral 15A denotes a setting spring which is interposed between the pusher 11A and the spool 9A, and which sets the pressure on the output port 7A side by the spool 9A according to the amount of pushing operation on the pusher 11A. 15A is located inside the spring 13 for return in the spring chamber 5, and
It is arranged with a predetermined preset load between A and the pusher 11A.

Reference numeral 16 is an arrow A, B, C by an operator or the like.
And D show the operating levers which are rocked in four directions, and the operating levers 16 include an operating shaft 17 and an operating shaft 17.
And a cam 18 which is swingably supported by the casing 1 by a ball joint 19 described later. The lower surface of the cam 18 is provided with the pusher 11
The pushers 11A, 11B are brought into contact with the upper end portions of the A, 11B and tilted in accordance with the swinging operation of the operation lever 16.
11B is pressed.

A ball joint 19 is provided between the casing 1 and the cam 18, and supports the operation lever 16 so as to be swingable. The ball joint 19 is the casing 1.
The spherical projection 21 is formed on the upper end side of the screw member 20 screwed to the center of the upper end of the cam, and the spherical concave portion 22 is provided on the lower surface side of the cam 18.
After fitting into the inside, the spherical recess 22 is formed by means such as caulking.
It is held in the state of being retained inside.

Reference numeral 23 denotes a connecting shaft provided between the operating shaft 17 and the cam 18. The connecting shaft 23 has a male screw portion formed on the upper end side screwed onto the operating shaft 17, and has an axially intermediate portion. The operation shaft 17 and the cam 18 are connected by sandwiching the provided large-diameter portion between the cam 18 and a nut screwed to the upper end side thereof.

Reference numeral 24 denotes a rotation stopping member provided on the lower end side of the connecting shaft 23, and the rotation stopping member 24 is fitted in a rotation preventing recess 25 provided in the spherical projection 21 of the screw member 20. . Here, as shown in FIG. 10, the detent member 24 is formed in a hexahedron shape having six arc surfaces 24a, 24a, ...
Six flat surfaces 25a having a hexagonal cross-section in the radial direction,
25a, ... The operation lever 16 can be swung in the four directions indicated by arrows A to D by engaging the circular arc surfaces 24a of the rotation stopping member 24 with the flat surfaces 25a of the rotation preventing recessed portion 25. It is designed so that it cannot rotate.

Next, the operation of the prior art pressure reducing valve type pilot valve having the above-mentioned structure will be described.

First, when the operating lever 16 is in the neutral position (initial position) as shown, the flow path 1 of the spool 9A is
0A shuts off the pump port 3 and the output port 7A,
Since the tank port 4 and the output port 7A are communicated with each other,
The output port 7A is kept in a low pressure state. The same applies to the spool 9B, and the output port 7B is also placed in a low pressure state. As a result, the directional control valve V1 is held in the neutral position.

Next, when the operation lever 16 is oscillated in one of the arrow A and B directions, for example, in the arrow A direction, the cam 18 tilts with the ball joint 19 as a fulcrum to push the pusher 11A downward in the axial direction. The spool 9A is operated according to the pressing operation amount at this time and the setting spring 15
Sliding displacement is axially downward via A. This allows
The flow path 10A of the spool 9A connects the pump port 3 and the output port 7A, and the tank port 4 and the output port 7A
And cut off. As a result, the output port 7A is placed in a high pressure state, and the pressure in the output port 7A acts on the spool 9A as a feedback pressure.
Is axially slid and displaced against the spring load of the setting spring 15A, and at this time, the setting spring 15A is compressed from the preset state and bends.

When the flow path 10A of the spool 9A again cuts off the pump port 3 and the output port 7A and connects the tank port 4 and the output port 7A to each other, the pressure in the output port 7A decreases. The setting spring 15A extends from the compressed state, and the setting spring 1
Due to the spring load of 5A, the spool 9A again slides downward in the axial direction. As a result, the flow path 1 of the spool 9A
Since 0A connects the pump port 3 and the output port 7A to each other and shuts off the tank port 4 and the output port 7A, the pressure in the output port 7A increases.

That is, a spring load corresponding to the amount of pushing operation on the pusher 11A is generated in the setting spring 15A, and the pressure in the output port 7A is controlled according to this spring load. Then, the direction switching valve V1 is switched from the neutral position to the switching position with a stroke amount according to the pressure (pilot pressure) in the output port 7A.

By controlling the directional control valve V1 to be switched by the operation of the pressure reducing valve section 2A, the amount of pressure oil flowing through the directional control valve V1 into the main circuit is gradually changed from a small flow rate to a large flow rate. The flow rate can be controlled. Even when the operation lever 16 is rocked in the direction of arrow B, as in the above-described rocking operation in the direction of arrow A,
The directional control valve V1 can be switched and controlled by the operation of the pressure reducing valve section 2B, and the flow rate of the pressure oil in the main circuit can be controlled.

When the operating lever 16 is swung in the directions of arrows C and D, the directional control valve V2 can be switched by operating the pressure reducing valve sections 2C and 2D, and the flow rate of the pressure oil in the main circuit can be controlled. Can be controlled.

[0024]

In the pilot valve according to the prior art as described above, in order to swingably support the operating lever 16 with respect to the casing 1, a space between the operating lever 16 and the casing 1 is provided. Spherical projection 2
1 and the spherical recess 22 are provided, the outer peripheral surface of the spherical projection 21 and the inner peripheral surface of the spherical recess 22 that compose the ball joint 19 are smoothly slid in a mutually fitted state. It is necessary to perform precise spherical surface machining so that it can move.

Further, in order to prevent the operation lever 16 from rotating around the axis during the swinging operation, the ball joint 1
Although the detent member 24 and the detent recess 25 are provided inside 9, the detent member 24 has six arc surfaces 24a, 24a,
Is formed in a hexahedron shape having ...
6 flat surfaces 2 so that the radial cross section is hexagonal
Since 5a, 25a, ... Are formed, the number of processing steps increases.

As described above, in constructing the ball joint 19, the spherical protrusion 21, the spherical recess 22 fitted into the spherical protrusion 21, the rotation-recessing recess 25 formed in the spherical recess 22 and the rotation-relief recess are formed. Since each component such as the detent member 24 that fits in the 25 is required and a large number of processing man-hours are required, the number of components and the processing cost are increased, and the manufacturing cost of the ball joint 19 is increased. There is a problem that it ends up.

The present invention has been made in view of the above-mentioned problems of the prior art, and it is possible to reliably prevent the rotation of the operating lever, reduce the number of parts, and reduce the man-hours for processing each part, thereby reducing the manufacturing cost. It is an object of the present invention to provide a pressure-reducing valve type pilot valve capable of being significantly reduced.

[0028]

In order to solve the above-mentioned problems, the pressure-reducing valve type pilot valve according to claim 1 is
A casing having a pump port, a tank port, and a plurality of output ports, a plurality of spools slidably and movably provided in the casing, and a plurality of spools for communicating the output ports with either the pump port or the tank port, A plurality of pushers for slidingly moving the respective spools, and a setting spring arranged between the respective pushers and the spools for setting the pressure on the output port side by the respective spools according to the pressing operation amount of the respective pushers. And an operating lever having a cam that comes into contact with each pusher in order to press each pusher against the setting spring.

The features of the configuration adopted by the present invention are:
A ball joint that swingably supports the operation lever is provided between the casing and the cam of the operation lever, and the ball joint is provided on one side of the casing and the cam of the operation lever. The fitting recess and the spherical projection that is provided on the other side and fits into the fitting recess, and the operation is performed in a state where the fitting recess and the spherical projection are fitted with the spherical projection. This is because a rotation prevention unit that prevents rotation of the lever is provided.

According to a second aspect of the present invention, the ball joint includes a fitting concave portion integrally formed with a screw member screwed to the casing and a spherical projection integrally formed with a cam of the operation lever. Can be configured.

Further, as described in claim 3, the rotation prevention portion is provided on the flat surface portion provided on the fitting recess and on the outer circumference of the spherical projection, and the radius of curvature of the outer circumference of the spherical projection is And arc surface portions having different radii of curvature.

[0032]

According to the first aspect of the present invention, when the operation lever is swung, the cam supported by the casing via the ball joint pushes the pusher. Then, the spool is slidably displaced by being pressed by the pusher via the setting spring, and the output port communicates with the pump port, whereby a pressure corresponding to the pusher operation amount of the pusher is obtained at the output port side. At this time, the rotation preventing portion provided on the spherical projection and the fitting recess forming the ball joint can reliably prevent the rotation of the operation lever during the swing operation.

According to the second aspect of the invention, the spherical projection integrally formed on the screw member screwed to the casing,
By configuring the ball joint with the fitting recess formed integrally with the cam, the number of parts can be reduced.

According to the third aspect of the invention, the rotation preventing portion of the ball joint is composed of the flat surface portion provided in the fitting recess and the circular arc surface portion provided in the spherical protrusion, thereby reducing the number of parts. In this state, the operation lever can be stopped.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. In the embodiment, the same components as those of the prior art shown in FIGS. 7 to 10 described above are designated by the same reference numerals, and the description thereof will be omitted.

First, FIGS. 1 to 4 show a first embodiment of the present invention.

In the figure, reference numeral 31 indicates a pressure reducing valve type pilot valve 31 according to the present embodiment, and the pressure reducing valve type pilot valve 31 has the same structure as the pressure reducing valve type pilot valve described in the prior art. 2D (only 2A and 2B are shown), the casing 1 has a pump port 3 and a tank port 4
And output ports 7A and 7B are provided. Also,
The pressure reducing valve sections 2A, 2B are slidably displaced so that the output ports 7A, 7B communicate with either the pump port 3 or the tank port 4, and spools 9A, 9B formed with flow paths 10A, 10B, Pushers 11A, 11B for pressing and slidingly moving the spools 9A, 9B, and a setting spring 15A for setting the pressure obtained on the output ports 7A, 7B side in accordance with the amount of pressing operation on the pushers 11A, 11B. , 15B.

However, the pressure reducing valve type pilot valve 31 according to the present embodiment is different from the prior art in the structure of the operating lever 32 and the ball joint 43.

Here, 32 is an operating lever that is rockably operated to press the pushers 11A and 11B, and the operating lever 32 has an operating shaft 33 having a male screw portion formed on the lower end side,
The cam 34 is swingably supported with respect to the casing 1 by a ball joint 43 described later.

As shown in FIG. 2, the cam 34 has a boss 35 extending in the axial direction and having a female screw portion formed on the inner peripheral side thereof.
And a disk-shaped cam body 36 located below the boss 35 and expanding in diameter, and the lower surface side of which contacts the upper ends of the pushers 11A and 11B, and a downward projection from the center of the lower surface side of the cam body 36. The spherical projection 3 is provided and has a substantially spherical tip.
7, and the boss 35, the cam body 36, and the spherical protrusion 37 are integrally formed. Here, on the outer periphery of the spherical projection 37, a spherical surface portion 37a and a single arc surface portion 37b having a radius of curvature larger than the radius of curvature of the spherical surface portion 37a are formed.

A male screw portion formed on the lower end side of the operating shaft 33 is screwed to a female screw portion formed on the boss 35 of the cam 34, and is fixed by a nut 38.

Reference numeral 39 denotes a screw member arranged in the center of the upper end side of the casing 1, and the screw member 39 is the casing 1.
The male screw 40 is screwed to the female screw portion, and the cylindrical portion 41 is provided so as to project upward from the male screw 40. The male screw 40 and the cylindrical portion 41 are integrally formed. Here, on the inner peripheral side of the cylindrical portion 41, as shown in FIGS. 3 and 4, an arcuate concave portion 42a into which the spherical surface portion 37a of the spherical projection 37 is fitted and a flat surface portion 42b into which the circular arc surface portion 37b is engaged.
And a conical concave portion 42c having a conical bottom portion 42c. The bottom 42c of the fitting recess 42 does not necessarily have to be formed in a conical shape, but may be formed in a spherical shape or a flat surface shape, for example.

After the screw member 39 is screwed to the female screw portion of the casing 1, the arc surface portion 37b and the flat surface portion 42b are formed.
The spherical projection 37 is fitted in the fitting recess 42 with a slight clearance while positioning so that
The upper end of 1 is reduced in diameter by means such as caulking over the entire circumference. As a result, the operation lever 32 is swingably supported with respect to the casing 1, and the arcuate surface portion 37b of the spherical protrusion 37 and the flat surface portion 42b of the fitting recess 42 are engaged with each other so that the operation lever 32 can rotate about the axis thereof. The ball joint 43 that prevents rotation can be formed.

That is, in the present embodiment, the operation lever 32 is mounted on the casing 1 by the spherical projection 37 integrally formed on the cam 34 and the fitting recess 42 of the cylindrical portion 41 integrally formed on the screw member 39. Constituting a ball joint 43 for swingably supporting the arcuate surface portion 37b formed on the spherical projection 37 and the flat surface portion 4 provided on the fitting recess 42.
The engagement portion with 2b constitutes a rotation prevention portion 44 that prevents the operation lever 32 from rotating around its axis.

The pressure reducing valve type pilot valve according to this embodiment is
It has the structure as described above, and its basic operation is not different from that of the prior art.

According to this embodiment, however, the spherical projection 37 formed integrally with the cam 34 is provided with the arcuate surface portion 37b, and the fitting recess 42 provided in the screw member 39 is fitted with the flat surface portion engaging with the arcuate surface portion 37b. By providing 42b, the spherical projection 37 is fitted into the fitting recess 42, and the ball joint 4
3 is formed, the arc surface portion 37b and the flat surface portion 42b are formed.
It is also possible to form the rotation preventing portion 44 including an engaging portion with.

Therefore, the detent member 2 described in the prior art is used.
4 and components such as a rotation stopper recess 25 provided in the spherical protrusion 21 for fitting the rotation stopper member 24 in the rotation stopper state, or a complicated component used only for preventing the rotation of the operation lever 16. No processing is required. Therefore, the number of parts can be reduced, the number of processing steps for individual parts can be reduced, and the manufacturing cost can be significantly reduced.

Next, FIG. 5 shows a second embodiment of the present invention. The feature of this embodiment is that a spherical projection and a fitting recess constituting a ball joint are screwed to a casing by a screw member. They are formed integrally with the cam of the operation lever.

In the figure, reference numeral 51 denotes a cam which constitutes an operating lever. Although the cam 51 has a boss 52 and a cam body 53 as in the first embodiment, the lower surface of the cam body 53 is not shown. A cylindrical bearing 54 is provided so as to project downward from the central portion. Then, the bearing 54 has a spherical projection 5 which will be described later.
8 is provided with an arc-shaped concave portion 55a into which the spherical surface portion 58a is fitted, and a flat surface portion 55b (indicated by a chain double-dashed line in the figure) with which the circular arc surface portion 58b is engaged.

Reference numeral 56 denotes a screw member screwed to the casing. The screw member 56 includes a male screw 57 and a male screw 57.
From the above, a spherical projection 58 protruding upward is integrally formed. Here, the spherical projection 58 has a spherical surface portion 58a and an arc surface portion 58b having a radius of curvature larger than the radius of curvature of the spherical surface portion 58a, as in the first embodiment.

After the screw member 56 is screwed into the casing, the spherical projection 58 is fitted into the fitting recess 55 with a slight gap while positioning so that the arc surface 58b and the flat surface 55b are engaged with each other. The ball joint 59 is formed by reducing the diameter of the lower end side of the bearing 54 by means such as caulking. Further, the arc preventing portion 60b is formed by the arc surface portion 58b and the flat surface portion 55b.

Also in this embodiment having the above-mentioned structure, it is possible to obtain the same effects as those of the first embodiment.

Further, FIG. 6 shows an essential part of the third embodiment of the present invention. The feature of this embodiment is that the rotation preventing parts provided in the spherical projection and the fitting recess are provided at a plurality of positions (two positions). It was established in.

In the figure, reference numeral 61 denotes a cam which constitutes an operating lever, and the cam 61 is similar to that of the first embodiment.
Although it has the cam body 63 and the spherical protrusion 64, the spherical protrusion 64 has two spherical portions 64a (only one is shown) and a radius of curvature larger than the radius of curvature of each spherical portion 64a. The two arcuate surface portions 64b, 64b that have the
For example, they are provided alternately at angular intervals of 90 degrees.

Reference numeral 65 designates a screw member screwed to the casing. The screw member 65 has a male screw 66 and a cylindrical bearing 67 as in the first embodiment, but the bearing 67 is provided. Includes two arcuate recesses 68a, 68a fitted into each spherical surface portion 64a of the spherical projection 64, and each arcuate surface portion 64.
Two flat surface portions 68b, 68b engaging with b are 90
Fitting recesses 6 that are alternately provided with an angular interval of 6 degrees
8 is formed.

After the screw member 65 is screwed into the casing, the spherical projection 64 is positioned in the fitting recess 68 with a slight gap while positioning so that the circular arc surface portions 64b and the flat surface portions 68b are engaged with each other. The ball joint 69 is formed by fitting and reducing the diameter of the upper end side of the bearing 67 by means such as caulking. In addition, each arc surface portion 64b
By engaging with the respective flat surface portions 68b, two rotation preventing portions 70, 70 are formed.

In this embodiment having the above-mentioned structure, the same effects as those of the first and second embodiments can be obtained. In particular, in this embodiment, each arc formed on the spherical protrusion 64 is formed. Since the rotation preventing portion 70 is formed at two locations by the engagement of the surface portion 64b and each flat surface portion 68b provided in the fitting recess 68, wear caused by sliding contact between the arc surface portion 64b and the flat surface portion 68b. Etc. can be reduced, and the rotation of the operating lever about the axis can be reliably prevented for a long period of time.

The anti-rotation portion is not limited to that of the above-mentioned embodiment, but is composed of a polyhedral projection such as the hexahedron shown in the prior art and a polyhedral fitting recess that fits into the projection. Good.

[0059]

As described in detail above, according to the invention of claim 1, the rotation preventing portion for preventing the rotation of the operating lever is provided in the spherical projection and the fitting recess forming the ball joint. It is possible to reliably prevent the operation lever from rotating during the operation. Moreover, when the ball protrusion is fitted into the fitting recess to form the ball joint, the rotation preventing portion can also be formed, so that the number of parts can be reduced and the manufacturing cost can be reduced. it can.

According to the invention of claim 2, a spherical projection integrally formed with a screw member screwed to the casing,
Since the ball joint is composed of the fitting recess formed integrally with the cam, it is possible to reduce the number of processing steps for processing individual parts.

Further, according to the invention of claim 3, since the rotation preventing portion of the ball joint is constituted by the flat surface portion provided in the fitting concave portion and the arc surface portion provided in the spherical protrusion, the rotation of the operation lever is prevented. Parts used only for prevention are unnecessary, the number of parts can be reduced, and the manufacturing cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a pressure reducing valve type pilot valve according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing a ball joint and the like in FIG. 1 in a partially enlarged manner.

3 is a cross-sectional view taken along the line III-III in FIG.

FIG. 4 is a vertical sectional view taken along the line IV-IV in FIG.

FIG. 5 is a perspective view similar to FIG. 2, showing a main part of a second embodiment of the present invention.

FIG. 6 is a perspective view similar to FIG. 2, showing a main part of a third embodiment of the present invention.

FIG. 7 is a plan view showing a pressure reducing valve type pilot valve according to a conventional technique.

FIG. 8 is a hydraulic circuit diagram showing a hydraulic pilot circuit using a pressure reducing valve type pilot valve according to a conventional technique.

9 is a vertical sectional view taken along the line IX-IX in FIG.

10 is a partially cutaway perspective view showing the ball joint and the like in FIG. 9 in a partially enlarged manner.

[Explanation of symbols]

 1 Casing 3 Pump Port 4 Tank Port 7A, 7B, 7C, 7D Output Port 9A, 9B Spool 11A, 11B Pusher 15A, 15B Setting Spring 32 Operation Lever 34, 51, 61 Cam 37, 58, 64 Spherical Protrusion 37b, 58b , 64b Arc surface portion 39, 56, 65 Screw member 42, 55, 68 Fitting concave portion 42b, 55b, 68b Flat surface portion 43, 59, 69 Ball joint 44, 60, 70 Rotation preventing portion

Claims (3)

[Claims] 1. A casing having a pump port, a tank port, and a plurality of output ports, and a plurality of casings slidably and movably provided in the casing for communicating the respective output ports with either the pump port or the tank port. And a plurality of pushers for slidingly moving the respective spools, and arranged between the respective pushers and the spools. The pressure on the output port side by the respective spools is adjusted according to the pressing operation amount of the respective pushers. A casing and an operating lever in a pressure-reducing valve type pilot valve comprising a setting spring to be set and an operating lever having a cam that abuts against each pusher for pressing the respective pushers against the setting spring. A ball joint for swingably supporting the operation lever, and the ball joint is
It comprises a fitting recess provided on one side of the casing and the cam of the operating lever, and a spherical projection provided on the other side and fitted in the fitting recess. Is a pressure reducing valve type pilot valve, characterized in that a rotation preventing portion for preventing rotation of the operating lever is provided in a state in which the spherical projection is fitted in the fitting concave portion. 2. The ball joint comprises a fitting recess integrally formed with a screw member screwed to the casing, and a spherical projection integrally formed with a cam of the operation lever. Pressure reducing valve type pilot valve. 3. The rotation preventing portion includes a flat surface portion provided in the fitting recess and an arc surface portion provided on the outer circumference of the spherical projection and having a radius of curvature different from the radius of curvature of the outer circumference of the spherical projection. The pressure reducing valve type pilot valve according to claim 1, which is configured.