KR20200025139A - Oil pressure adjustment valve with improved damping malfunction prevention structrue - Google Patents

Abstract

The present invention provides a hydraulic pressure adjustment valve with an improved damping malfunction preventing structure. The hydraulic pressure adjustment valve comprises: a valve body (3) provided with a working oil chamber (6) and at least one port (7) therein; a plurality of spools (8) inserted and installed into the valve body (3) to be movable in a longitudinal direction through the port (7) and the working oil chamber (6) for adjusting the flow of a working oil; a plurality of spool holes (9) provided within the valve body (3) to guide reciprocating motion of the spools (8) in a longitudinal direction and communicating with or blocking a connection to the working oil chamber (6) by the longitudinal reciprocating motion of the spools (8); a pushing cam (10) connected to an upper side of the valve body (3) via a joint to perform a seesaw motion based on the joint; a push rod (5) pushing the spools (8) while being pushed by the pushing cam (10); a damping chamber (18) formed between the outer circumferential surface of the push rod (5) and the valve body (3); a lower push rod (22) coupled to the push rod (5) to divide the damping chamber (18) into a neutral damping chamber (18A) and a shock-absorbing damping chamber (18B); and a shock-absorbing damping spring (32) provided in the lower shock-absorbing damping chamber (18B) to be arranged on the bottom of the lower push rod (22).

Description

Oil pressure adjustment valve with improved damping malfunction prevention structrue}

The present invention relates to a hydraulic control valve of a new configuration that can prevent the occurrence of malfunction due to the sudden spring force of the return spring at the neutral return after the operation.

In general, in construction equipment such as excavators and rods, a pilot valve (hydraulic control valve) operated by a joystick is widely used, and a spool is operated in response to a driver's pedal to enable driving in response to pilot signal pressure generated. The actuator that drives the hydraulic motor is activated. In the case of the hydraulic control valve, the downward force is applied to the push rod by operating the lever, and when the spool is pushed down by the push rod and opened due to the downward force on the push rod, the corresponding port (supply port) is opened. When the hydraulic oil is discharged, and the hydraulic oil is discharged to the corresponding port, for example, the left and right tracks of the excavator are rotated in the forward or reverse direction, or only one of the left and right tracks is driven so as to operate in the driving track direction. . 1 and 2 are photographs showing a track and a wheel employing a hydraulic control valve.

Conventional hydraulic control valve has a lever pedal operated by the operator by hand or foot is connected to the valve body by a joint and a plurality of push rods protrude from the upper side of the valve body. Press to move the spool connected to the bottom of the push rod in the spool hole.

A hydraulic oil chamber is formed in the valve body, and the hydraulic oil is returned to the tank through a return port formed at the center portion, and the hydraulic oil (hydraulic oil) supplied from the external hydraulic pump and the actuator to the hydraulic oil chamber is discharged to each port of the valve body to operate the actuator of the work machine. It acts as a signal pressure. In other words, the valve body is provided with a plurality of (usually two) ports, the inside of the valve body is provided with a port connected to the external hydraulic pump and the actuator, the hydraulic oil chamber connected to the external hydraulic oil tank is the upper side of the port The hydraulic oil chamber has a structure that communicates with the port or blocks communication with the port according to the operation of the spool provided in each port, so that the pushing cam is moved by means of mechanical operation means for operating the lever. When the spool is lowered and the spool is lowered, the hydraulic chamber and the port of the pressed spool side communicate with each other, and the hydraulic oil in the hydraulic chamber is supplied to the port where the spool is pressed to actuate the actuator signal pressure of the working machine such as the excavator. It can be driven and the spool is brought back up by a spring. That is, the hydraulic control valve is a state in which each spool is blocking the flow path between each port and the hydraulic oil chamber (operator track, etc.) is in a non-operation state, in this state by the spool operated by the operator's pedal operation When the flow path between the port and the oil chamber is opened, the signal pressure (oil pressure) through the port in communication with the oil chamber is supplied to the actuator so that, for example, the boom of the rod is stretched or the track of the excavator is operated. When the spool returns to its original state by the force of the spring, the hydraulic oil returns to the hydraulic oil chamber through a return port formed at the center of the valve body.

In heavy equipment such as an excavator or a crane, the pilot hydraulic operation valve (hydraulic control valve) is operated by a pushing cam connected to a pedal that rotates to operate the driving, and the spring has a spring when the pushing cam returns to the neutral position. It is configured to return to the neutral position by the elastic force.

However, when the pushing cam and the joystick connected thereto are returned to the neutral position, the pushing cam and the joystick touch the opposite ports beyond the neutral position by the repulsive force caused by the excessive elastic force of the spring, thereby causing malfunction or vibration of the device itself. Malfunctions and vibrations caused by these hydraulic control valves can cause serious problems in the service life and safety of heavy equipment. When the spool and the pushing cam, which are the main parts of the hydraulic control valve, return to neutral, the damping malfunction occurs when the pushing cam and the joystick touch the opposite port beyond the neutral position due to the repulsive force caused by the excessive elastic force of the spring. May cause.

Korean Patent Publication No. 10-1998-087734 (published Dec. 5, 1998) Domestic registered patent No. 10-0803963 (registered Feb. 11, 2008)

The present invention for the operation of the bucket of the excavator, the main object of the present invention is to provide a hydraulic control valve of a new configuration that can prevent in advance the malfunction caused by the sudden spring force of the return spring at the neutral return after the operation to be. The hydraulic control valve has an elastic force of the spring at the time of neutral return after the operation (for example, after the joystick operation), resulting in an unexpected sudden signal change. At this time, since the driving device also affects the driving feeling and stability, the present invention has an object to improve such a problem.

According to the present invention for solving the above problems, a valve body having a hydraulic oil chamber and at least one port therein; A plurality of spools inserted into the valve body so as to be movable in the longitudinal direction through a port and a hydraulic oil chamber to regulate the hydraulic oil flow; A plurality of spool holes provided in the valve body to guide the spool in the longitudinal direction and connected to or disconnected from the working oil chamber by the longitudinal reciprocating motion of the spool; Pushing cam connected to the upper side of the valve body via a joint to seesaw movement relative to the joint; A push rod that presses the spool while being pressed by the pushing cam; A damping chamber formed in the valve body to be disposed below the push rod; A lower push rod coupled to the push rod to partition the damping chamber into a neutral damping chamber and a pull up damping chamber; And a damping damping spring provided in the damping damping chamber so as to be disposed on a bottom surface of the lower push rod.

And a support member provided in the pull-up damping chamber to be disposed below the lower push rod, wherein the pull-up damping spring is interposed between the lower push rod and the support member.

The upper end and the lower end of the shock-up damping spring may be in contact with the bottom of the lower push rod and the top of the support member, respectively.

Spring mounting grooves are further provided on the bottom surface of the lower push rod and the top surface of the support member, respectively.

The shock-up damping spring is characterized by consisting of a tapered spring whose outer diameter is gradually larger from the upper end to the lower end.

The shock-up damping spring is characterized by having a coating layer surrounding the outer surface.

An inner orifice communicating with the neutral damping chamber and the shock-up damping chamber may be provided in the lower push rod.

The valve body is characterized in that the main hydraulic passage for supplying the main hydraulic pressure to the neutral damping chamber is provided.

The main hydraulic passage comprises a center main hydraulic passage extending in the vertical direction of the valve body and a plurality of branch main hydraulic passages radially branched from the center main hydraulic passage to communicate with the neutral damping chamber. It is done.

Since the hydraulic damping valve of the present invention has a damping damping function in which the damping spring is buffered at the neutral return after the operation, the elastic force of the returning spring at the neutral return after the hydraulic pressure regulating valve is operated for the operation of the excavator or the like. This prevents accidental sudden signal changes (damping malfunctions) and prevents accidental sudden signal changes from affecting the driving system, causing problems with driving comfort and stability. It is effective to prevent things in advance.

1 is a longitudinal sectional view showing a structure of a hydraulic control valve strengthening a damping malfunction prevention structure according to the present invention;
Figure 2 is a longitudinal cross-sectional view showing a state in which the main spool shown in Figure 1 is pressed
Figure 3 is a longitudinal sectional view showing a structure of a hydraulic control valve strengthening the damping malfunction prevention structure according to another embodiment of the present invention
Figure 4 is a longitudinal sectional view showing a state in which the spool which is the main part shown in Figure 3 is pressed
Figure 5 is a longitudinal sectional view showing a structure of a hydraulic control valve strengthening the damping malfunction prevention structure according to another embodiment of the present invention
Figure 6 is a longitudinal sectional view showing a modified embodiment of the portion supporting the pull-up damping spring which is the main part of the present invention;

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The objects, features and advantages of the present invention will be more readily understood by reference to the accompanying drawings and the following detailed description. In addition, in describing the present invention, if it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. For example, if a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected or connected to that other component, but between each component. It is to be understood that another component may be "connected", "coupled" or "connected".

Referring to the drawings, the hydraulic control valve strengthening the damping malfunction prevention structure according to the present invention is a valve body (3) having a hydraulic oil chamber (6) and at least one port (7) therein, and such a valve body (3) A plurality of spools (8) inserted into the port (7) and the hydraulic oil chamber (6) so as to be movable in the longitudinal direction to regulate the fluid flow, and the valve body to guide the spool (8) in the longitudinal direction. (3) a plurality of spool holes (9) communicated with or disconnected from the hydraulic oil chamber (6) by a longitudinal reciprocating motion of the spool (8) and a joint at the upper side of the valve body (3) Pushing cam 10 which is connected via a means to seesaw movement with respect to the joint, the push rod 5 for pressing the spool 8 while being pressed by the pushing cam 10 and the outer peripheral surface of the push rod 5 And a damping chamber 18 formed between the valve body 3 and the damping chamber 1. 8) the lower push rod 22 coupled to the push rod 5 to partition the damping chamber 18A into the neutral damping chamber 18A and the damping damping chamber 18B, and the damping damping chamber to be disposed on the bottom surface of the lower push rod 22. The damping damping spring 32 provided in 18B is provided.

In the present invention, a plurality of (at least two or four) spools 8 are provided in the valve body 3 so that the spools can be lifted and lowered. A push rod 5 installed on the upper portion of the 8, a pushing cam 10 adapted to press the push rod 5 into the valve body 3, and a return spring 13 supporting each of the spools 8 upwardly; 13 is provided. On the other hand, the pushing cam 10 is connected to the upper side of the valve body 3 via a joint to seesaw movement relative to the joint, the pushing cam 10 is connected to the pushing cam 10 according to the operation A lever (not shown) which moves the seesaw and the spool 8 reciprocates in the spool hole 9 to open and close the port 7 with respect to the hydraulic oil chamber 6, and the pushing cam 10 is operated by operating the lever. And a damping chamber 18 formed between the outer circumferential surface of the push rod 5 and the valve body 3 while being pushed in the seesaw movement and pressing the spool 8. A damping damping spring 32 is provided on the bottom of the lower push rod 22.

The valve body 3 has a structure in which a port 7 connected to an external hydraulic pump and an actuator is provided at an inner lower side thereof, and a hydraulic oil chamber 6 connected to an external hydraulic oil tank is provided at an upper side thereof. A connecting flow path is formed between the port 7 and the hydraulic oil chamber 6 so that the spool 8 is movable, respectively, and a spool hole 9 into which the lower end of the spool 8 is inserted below the connecting flow path. ) Is formed. The spool holes 9 are connected to each other through a connection flow path inside the valve body 3 so that the intermediate connection flow path and the spool hole 9 are closed when the spool 8 is closed. The valve body 3 may have a structure branched in the radial direction with respect to the center. Although not shown, the port 7 is formed with a pump port 7 connected to the hydraulic pump, and the hydraulic oil chamber 6 is formed with a tank port 7 connected to the hydraulic oil tank.

The push rod 5 has a lower end connected to each spool 8 and an upper end protruded out of the valve body 3 so that the push rod 5 can be moved up and down by a guide in the form of a single pipe, and the push rod 5 and the spool ( An annular support plate is provided at the connecting portion of 8), and return springs 13 and 13 are installed inside the hydraulic oil chamber 6 so as to support the support plate upward.

The pushing cam 10 is connected to the center of the upper side of the valve body 3 by a joint (which may be a universal joint, if necessary), and rotates in the form of a seesaw on the upper portion of the valve body 3. It is arrange | positioned as possible. The pushing cam 10 has a portion spaced apart from the center of rotation (that is, the joint portion) to press the upper end protruding to the outside of the push rod (5). A connecting shaft having a screw portion is provided at an outer circumferential surface of the upper side central portion of the pushing cam 10, and a screw portion is provided at an outer circumferential surface of a lower end side of the lever disposed above the pushing cam 10, and the screw portion and the pushing portion of the lever are provided. The levers are mutually connected to the pushing cam 10 by a nut that is commonly coupled to the threaded portion of the connecting shaft of the cam 10. Precisely, a screw hole is formed in a central portion of the pushing cam 10, and a connecting shaft having a screw portion is provided at an outer circumferential surface at a central portion of the upper surface of the joint, and a screw of the pushing cam 10 is formed on the outer circumferential surface of the joint The lever and the pushing cam 10 are bolted to the hole, and the nut is commonly coupled to the screw portion of the outer circumferential surface of the connecting shaft and a screw portion of the lever outer circumferential surface, the portion of which protrudes toward the upper surface of the pushing cam 10. It may have an interconnected structure.

The spool 8 is inserted into the valve body 3 so as to be movable in the longitudinal direction through the port 7 and the hydraulic oil chamber 6 to regulate the fluid flow between the hydraulic pump, the actuator and the hydraulic oil tank. A plurality of spools 8 are provided based on the center of 3). In the present invention, four spools 8 are provided based on the central portion of the valve body 3.

On the other hand, in the embodiment of the present invention the port 7 is made in the form of a pipe and the hydraulic oil chamber 6 is made in the form of a room, two flow paths, that is, the two ports 7 are arranged up and down Although illustrated, the present invention is not limited thereto, and it should be understood that the present invention can be applied to a conventional valve having a port 7 and a hydraulic oil chamber 6 in various forms and positions. In addition, although the pushing cam 10 and the return springs 13 and 13 are illustrated as an operating means for reciprocating the spool 8 in the embodiment of the present invention, the operating means is a spool ( It can be of various structures for reciprocating 8).

The valve body 3 is provided with a spool hole 9 for reciprocating the spool 8 in the longitudinal direction. The spool hole 9 has a spool 8 of the valve body 3. It is formed in the up-down direction inside the valve body 3 so that the relative lifting in the up-down direction. This spool hole 9 is in communication with or disconnected from the hydraulic oil chamber 6 by the longitudinal reciprocating motion of the spool 8. That is, the flow path between the spool hole 9 and the hydraulic oil chamber 6 can be opened and closed according to the reciprocating motion of the spool 8.

In addition, the valve body 3 is provided with a hydraulic oil chamber 6 at an upper position inside the spool hole 9, and a guide hole 4 directly above the spool hole 9 at the upper portion of the hydraulic oil chamber 6. It is provided. The lower end of the guide hole 4 communicates with the hydraulic oil chamber 6, and the upper end thereof communicates with the upper side of the valve body 3. The push rod 5 is slidably coupled to the guide hole 4, and the upper end of the spool 8 is connected to the lower end of the push rod 5 via the support plate, so that the pushing cam 10 The push rod 5 is pressed according to the seesaw movement of the spool, and when the push rod 5 is pressed, the spool 8 is pushed down so that the flow path between the hydraulic oil chamber 6 and the port 7 can be opened. do.

The overall operation of the hydraulic control valve of the present invention is made similar to the conventional one. That is, when the operator pushes or pulls the lever to rotate the pushing cam 10, the push rod 5 on one side that is selectively pressed lowers the spool 8 connected to the lower part thereof, When the force is released, the spool 8 is returned upward by the return springs 13 and 13, and the hydraulic pressure through the port 7 and the hydraulic oil chamber 6 depends on the position of each spool 8 by this operation. The hydraulic oil supply direction and the flow rate between the pump and the actuator and the hydraulic oil tank are controlled, which causes the bucket of the excavator to operate. The present invention can be applied to both a general working machine and a hydraulic system having a hydraulically operated actuator such as an excavator, a hydraulic motor, a hydraulic cylinder, etc. For example, the pushing cam 10 is hinged by operating a joystick provided in the excavator. When pushing by the part, the push rod 5 descends and pushes the spool 8 so that the flow path 7 of the spool 8 is opened from the pump port so that the hydraulic pressure operates the working machine or the hydraulic system. As such, it is common to operate the excavator or the hydraulic system by the operation of the hydraulic control valve 1, and thus, further detailed description of the operation of the present invention will be omitted.

In the present invention, the damping function is strengthened to prevent an unintended signal (here, the signal means that hydraulic oil of the working oil) is generated by the sudden spring force of the return spring 13 at the neutral return. There is a characteristic. To this end, the present invention basically includes a neutral damping chamber 18A, a shock-up damping chamber 18B, a lower push rod 22, and a shock-up damping spring 32.

A guider 7 is slidably coupled to a guide hole provided in the valve body 3, and the guider 7 is disposed under the pushing cam 10, and the push rod 5 ) Is built in the damping chamber 18 inside the valve body 3 in a state arranged below the guider 7 so as to be able to lift and lower. The push rod 5 is pressed by the pushing cam 10, the lower push rod 22 is coupled to the outer circumferential surface of the push rod 5, and the damping chamber 18 is driven by the lower push rod 22. ) Is divided into a neutral damping chamber 18A and a bottom-up damping chamber 18B. A support member is provided to be disposed below the lower push rod 22. A damping chamber 18 is secured between the support member and the guider 7. The damping chamber 18 is partitioned into a neutral damping chamber 18A and a damping damping chamber 18B by a lower push rod 22. The neutral damping chamber 18A is provided on the upper side with respect to the lower push rod 22, and the shock-up damping chamber 18B is provided on the lower side. In addition, the lower push rod 22 has a side wall extending downward. When viewed from the longitudinal section of the valve body, the lower push rod 22 is configured to have a cross-sectional recessed shape that opens downward.

A shock-absorbing damping spring 32 is incorporated in the shock-damping chamber 18B so as to be disposed on the bottom of the lower push rod 22.

The valve body 3 is provided with a hydraulic oil chamber 6 to be disposed under the support member. The hydraulic oil chamber 6 is provided with a spool 8 connected to the push rod 5.

A return spring 13 is interposed between the bottom surface of the hydraulic oil chamber 6 and the lower end of the push rod 5. The lower end of the return springs 13 and 11 touches the bottom surface of the hydraulic oil chamber 6 and the upper end of the spring 11 touches the lower end of the push rod 5.

According to the present invention, when an external operation signal for pushing the pushing cam 10 comes in such that an operator such as an excavator grabs a lever, the pushing cam 10 is pushed to either side while being seesawed relative to the hinge. If the pushing cam 10 is pressed in either direction, the pushing cam 10 presses the push rod 5 and the spool 8 is lowered by the push rod 5 being pressed. As the lower end of the spool 8 descends while the spool 8 descends, the corresponding port 7 opens and oil is supplied when the spool 8 descends.

Next, when the external signal for pushing the pushing cam 10 is released, such as causing the return rotation operation of the lever, the pushing cam 10 presses the push rod 5 and the spool 8 to release the return signal. When the return spring 13 is pushed back, the push rod 5 is pushed upward again to return to the neutral position. When the push rod 5 returns to the neutral position, the pushing cam 10 rotates. The push rod 5 and the lower push rod 22, which are different from the push rod 5 and the lower push rod 22, which are pushed back to their original neutral positions and are pushed up and lower again.

When the push rod 5 and the lower push rod 22 which have been raised in this way are lowered and the push rod 5 and the lower push rod 22 are about to descend by the elastic force of the return spring 13, the lower portion Since the shock-up damping spring 32 under the push rod 22 acts as a shock-absorbing damping function by receiving a force of descending sharply, the shock-up damping spring 32 returns to a neutral return after the hydraulic control valve is operated for the operation of an excavator or the like. It is prevented that the spring force of the spring 13 occurs to cause an unexpected sudden signal change. At this time, if the elastic force of the return spring 13 occurs during the neutral return after the operation of the hydraulic control valve, and causes an unexpected sudden change of the signal, it also affects the traveling device. In the present invention, the shock-absorbing damping spring 32 under the lower push rod 22 acts as a shock-absorbing damping function that receives shocks of a sharply descending force and thus cushions the shock.

Meanwhile, in the present invention, the lower push rod 22 is provided with an orifice 22OP communicating from the top to the bottom, and the orifice 22OP is provided with an upper neutral damping chamber 18A and a lower damping damping chamber 18B. When the push rod 5 and the lower push rod 22 are pressed, hydraulic pressure filled in the damping damping chamber 18B is supplied to the neutral damping chamber 18A through the orifice 22OP, so that the push rod 5 and the lower push rod 22 are pressed. Operation of the rod 5 and the lower push rod 22 can be made smoothly.

In addition, when the push rod 5 and the lower push rod 22 are pressed, and the neutral return, the push rod 5 and the lower push rod 22 are raised again, which is provided in the lower push rod 22. When the hydraulic pressure filled in the neutral damping chamber 18A flows back into the damping damping chamber 18B through the orifice 22OP, the push rod 5 and the lower push rod 22 which are pushed up smoothly rise smoothly. It is possible to return.

In addition, in the present invention, it is possible to smoothly supply the hydraulic pressure using the main hydraulic pressure, and due to the installation of the damping damping spring 32, the lower push rod 22 may be clearly operated. Definite behavior of the lower push rod 22 means that the lower push rod 22 is prevented from being biased or distorted to one side during the lifting operation of the lower push rod 22, thereby enabling precise operation of the hydraulic control valve. At this time, the center main hydraulic flow passage 42A extending in the vertical direction in the valve body 3 and the plurality of branches branched in the radial direction from the center main hydraulic flow passage 42A to communicate with the neutral damping chamber 18A. The main hydraulic flow passage 42B is provided, and the main hydraulic pressure raised from the center main hydraulic flow passage 42A is evenly supplied to each of the neutral damping chambers 18A through the plurality of branch main hydraulic flow passages 42B. The push rod 5 and the lower push rod 22 can be operated uniformly and precisely without deviation. The main hydraulic flow passage 42 including the center main hydraulic flow passage 42A and the branch main hydraulic flow passage 42B is configured to receive the main hydraulic pressure from a main hydraulic device not shown. The main hydraulic flow passage 42 may be configured to communicate with the hydraulic oil chamber 6. The center main hydraulic flow passage 42A may pass through the hydraulic oil chamber 6 so that the main hydraulic flow passage 42 may be in communication with the hydraulic oil chamber 6.

The damping damping spring 32 is composed of a tapered spring whose outer diameter becomes larger and larger from the upper end to the lower end.

When the pull-up damping spring 32 is configured as a tapered spring, when the lower push rod 22 is pressed or raised, the lower push rod 22 is not shaken in the left-right direction when the lower push rod 22 is pushed up. Since it is reliably pressed and rises still, there is an effect of improving the reliability in operating the hydraulic control valve by preventing the occurrence of a faulty hydraulic supply between the neutral damping chamber 18A and the damping damping chamber 18B. When the upper push rod (5) is stably lifted by the tapered spring-type damping damping spring (32) and biased to either side to increase the friction force on the inner wall surfaces of the neutral damping chamber (18A) and the damping damping chamber (18B). Also, since the accuracy of the neutral damping chamber 18A and the damping damping chamber 18B due to the frictional force is reduced, obstacles in operating the hydraulic control valve are reduced. It can be eliminated, and further by reducing wear due to friction life of the oil pressure control valve itself lengthening effect is had.

In addition, the present invention further includes a coating layer 32CT surrounding the outer surface of the shock-up damping spring 32. The coating layer 32CT may be formed of a resin. The coating layer 32CT is preferably made of a resin having properties such as wear resistance while having corrosion resistance to hydraulic oil.

When the outer surface of the shock-up damping spring 32 is wrapped with the coating layer 32CT, it is more preferable to prevent deterioration such as oxidation of the shock-up damping spring 32 with respect to the hydraulic oil. By preventing the deterioration or the deterioration period of the damping damping spring 32, it is more helpful in extending the life of the hydraulic control valve.

On the other hand, the upper end and the lower end of the damping damping spring 32 are in contact with the bottom surface of the lower push rod 22 and the upper surface of the support member, respectively, preferably the bottom surface of the lower push rod 22 and the upper surface of the support member, respectively. A seating groove is further provided.

Thus, the upper end of the shock-absorbing damping spring 32 enters into and engages the spring seating groove of the bottom of the lower push rod 22, and the lower end of the shock-up damping spring 32 enters into and engages the spring seating groove of the upper surface of the support member. The damping damping spring 32 is positioned more stably between the lower push rod 22 and the support member, so that it is structurally more stable. When the push rod 5 and the lower push rod 22 are lifted and operated, By more reliably preventing the shaking in the left-right direction from the damping damping spring 32 side, ultimately, the effect of further increasing the stability and reliability in the damping operation of the hydraulic control valve can be expected.

In the above, the specific Example of this invention was described above. However, the spirit and scope of the present invention is not limited to these specific embodiments, and various changes and modifications can be made without departing from the spirit of the present invention. Those who have it will understand.

Therefore, the embodiments described above are provided to fully inform the scope of the invention to those of ordinary skill in the art to which the present invention pertains, and should be understood as illustrative and not limiting in all respects. The invention is only defined by the scope of the claims.

3. valve body 5. push rod
8. Spool 9. Spool Hole
10. Pushing Cam 18. Damping Chamber
18A. Neutral Damping Chamber 18B. Shock-up damping chamber
22. Lower push rod 32. Pull-up damping spring
42. Main hydraulic flow path 42A. Center main hydraulic flow path
42B. Branch Main Hydraulic Euro

Claims (6)

A valve body 3 having a hydraulic oil chamber 6 and at least one port 7 therein;
A plurality of spools (8) installed in the valve body (3) so as to be movable in the longitudinal direction through a port (7) and a hydraulic oil chamber (6) to regulate the hydraulic oil flow;
A plurality of spools provided in the valve body 3 to guide the spool 8 in the longitudinal direction and connected to or disconnected from the hydraulic oil chamber 6 by the longitudinal reciprocating motion of the spool 8. Holes 9;
Pushing cam 10 is connected to the upper side of the valve body 3 via a joint to seesaw movement relative to the joint;
A push rod (5) pressed by the pushing cam (10) to press the spool (8);
A damping chamber 18 formed inside the valve body 3 to be disposed under the push rod 5;
A lower push rod 22 coupled to the push rod 5 to partition the damping chamber 18 into a neutral damping chamber 18A and a pull-up damping chamber 18B;
And a damping damping spring (32) provided in the pull-up damping chamber (18B) so as to be disposed on the bottom of the lower push rod (22).
The method of claim 1,
And a support member provided in the pull-up damping chamber 18B to be disposed below the lower push rod 22, wherein the pull-up damping spring is disposed between the lower push rod 22 and the support member. 32) is a hydraulic control valve strengthening the damping malfunction prevention structure characterized in that.
The method of claim 2,
An upper end portion and a lower end portion of the damping damping spring 32 are in contact with a bottom surface of the lower push rod 22 and an upper surface of the support member, respectively.
The method of claim 1,
Hydraulic control valve having a malfunction prevention function, characterized in that the lower push rod 22 is provided with an orifice (22OP) in communication with the neutral damping chamber (18A) and the pull-up damping chamber (18B).
The method of claim 1,
The hydraulic control valve having a malfunction prevention function, characterized in that the main hydraulic passage for supplying the main hydraulic pressure to the neutral damping chamber (18A) is provided inside the valve body (3).
The method of claim 5,
The main hydraulic passage includes a center main hydraulic passage extending in the vertical direction of the valve body 3 and a plurality of branch main hydraulic passages branched radially from the center main hydraulic passage to communicate with the neutral damping chamber 18A. Hydraulic control valve with a malfunction prevention function, characterized in that configured to include.

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