JP7093287B2 - Control valve - Google Patents

Description

The present invention relates to a control valve that controls the flow of working fluid.

As a control valve used in a fluid pressure control device, a manual control valve whose position is switched by a manual operation by an operator is known (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 6-227789

In the manual control valve of Patent Document 1, the valve body is accommodated in the accommodating hole opened at the end of the housing, and a cap is provided so as to close the opening of the accommodating hole. Inside the cap, a spring is provided to urge the valve body to one side. The position of the control valve is switched by manually moving the valve body against the urging force of the spring.

In such a manual control valve, there is a demand that the position can be switched by an external signal, for example, when confirming the operation on an automatic inspection line.

As a method of operating the control valve by a signal from the outside, for example, it is conceivable to supply a pilot pressure to the inside of the cap to move the valve body. However, manual control valves are generally configured to drain the pressure in the cap through a drain passage that communicates with the tank. Therefore, even if the pilot pressure is guided into the cap, the urging force to move the valve body cannot be exerted.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a manual switching type control valve that can be operated by an external signal.

The present invention is a control valve for controlling the flow of working fluid, which is a housing, a housing hole formed in the housing and opened at the end face of the housing, a valve body slidably inserted into the storage hole, and a storage hole. A cap that seals the opening of the valve, an urging member that urges the valve body in one direction, and a switching unit that is provided on the cap and moves the valve body against the urging force of the urging member by manual operation. A pilot pressure chamber formed inside the cap to guide the pilot pressure that urges the valve body against the urging force of the urging member, a pilot port formed in the cap to guide the pilot pressure to the pilot pressure chamber, and a pilot pressure. It is characterized by including a drain passage for releasing the pressure of the chamber to the tank and a throttle portion provided in the drain passage to give resistance to the flow of the working fluid passing through the drain passage.

The present invention is characterized in that the switching portion is a switching bolt that is screwed into a screw hole formed in the cap and advances and retreats with respect to the valve body by manual operation.

In these inventions, a drain passage for releasing the pressure in the pilot pressure chamber is provided, and a throttle portion is provided in the drain passage. When the pilot pressure is guided to the pilot pressure chamber, a part of the working fluid in the pilot pressure chamber is discharged through the drain passage, but resistance is applied by the throttle portion, so that a predetermined pressure is generated in the pilot pressure chamber. Therefore, by supplying the pilot pressure to the pilot pressure chamber, a thrust for moving the valve body is generated in the pilot pressure chamber, and the valve body can be moved.

The present invention further includes a pair of seating members provided in the cap, in which both ends of the urging member are seated and move relative to each other as the urging member expands and contracts. It is characterized in that the movement of the valve body against the urging force of the member is restricted. In the present invention, since the movement of the valve body can be restricted by the seating member, the movement amount of the valve body can be easily adjusted by changing the seating member.

The present invention is characterized in that the drain passage always communicates the pilot pressure chamber and the tank, and the communication opening degree of the drain passage to the tank is constant regardless of the stroke position of the valve body.
In the present invention, one of the pair of seating members has a flange portion in contact with the end face of the housing, and the pilot pressure chamber and the drain passage are always communicated with the end face of the flange portion in contact with the end face of the housing. It is characterized in that a slit is formed.

According to the present invention, there is provided a control valve that is operated by manual operation as well as by pilot pressure.

It is sectional drawing of the control valve which concerns on embodiment of this invention, and is the figure which shows the state which is in a communication position. It is sectional drawing of the control valve which concerns on embodiment of this invention, and is the figure which shows the state which is the shutoff position. It is sectional drawing of the control valve which concerns on embodiment of this invention, and is the figure which shows the state which was switched to the shutoff position by a pilot pressure.

Hereinafter, the control valve 100 according to the embodiment of the present invention will be described with reference to the drawings.

The control valve 100 is used in a fluid pressure control device (not shown) mounted on a construction machine such as a hydraulic excavator, and is a working fluid guided from a fluid pressure supply source (not shown) to a fluid pressure device (not shown) or the like. It controls the flow of. In the following embodiment, the case where the working fluid is hydraulic oil will be described. The hydraulic fluid is not limited to the hydraulic fluid, and may be another incompressible fluid or a compressible fluid.

The control valve 100 is a two-position control valve that is switched between two positions by moving the spool 10. As shown in FIG. 1, the control valve 100 includes a housing 1, an accommodating hole 1A formed in the housing 1 that opens into the end surface 1B of the housing 1, and a spool as a valve body slidably inserted into the accommodating hole 1A. A spring 35 provided in the cap 30 as a urging member for urging the spool 10 in one direction, a cap 30 for sealing the opening of the accommodating hole 1A, and a spring provided in the cap 30 by manual operation. A switching unit 40 that moves the spool 10 against the urging force of the 35, and a pilot pressure chamber 50 that is formed inside the cap 30 and induces a pilot pressure that urges the spool 10 against the urging force of the spring 35. As a pair of seating members formed in the cap 30 and guiding the pilot pressure to the pilot pressure chamber 50, and provided in the cap 30, both ends of the spring 35 are seated and move relative to each other as the spring 35 expands and contracts. The spring seats 60 and 65 are provided.

The inflow passage 2A and the outflow passage 2B through which the hydraulic oil flows are formed in the housing 1 so as to be arranged in the axial direction. The inflow passage 2A communicates with the accommodating hole 1A and communicates with the fluid pressure supply source via a pipe or the like (not shown). The outflow passage 2B communicates with the accommodating hole 1A and communicates with the hydraulic equipment or the like via a pipe or the like (not shown). Further, a tank port 2C communicating with the tank T is formed at the bottom of the accommodating hole 1A. The tank port 2C guides the hydraulic oil guided between the bottom of the accommodating hole 1A and the end of the spool 10 to the tank T.

The spool 10 has a main body portion 11 that is in sliding contact with the inner peripheral surface of the accommodating hole 1A, and a support portion 20 that is attached to one end (left end in the drawing) of the main body portion 11.

The main body portion 11 is formed to have a smaller diameter than the first land portion 12 and the second land portion 13 sliding along the inner peripheral surface of the accommodating hole 1A, and the first land portion 12 and the second land portion 13. It has a connecting portion 14 that connects the portion 12 and the second land portion 13.

The connecting portion 14 is formed to have a smaller diameter than the first land portion 12 and the second land portion 13, and forms an annular fluid chamber 5 with the inner peripheral surface of the accommodating hole 1A. The fluid chamber 5 communicates with the inflow passage 2A and the outflow passage 2B as it moves to the spool 10, and guides the hydraulic oil that has passed through the inflow passage 2A to the outflow passage 2B.

One end of the main body 11 is provided with a first small diameter portion 15 having an outer diameter smaller than the inner diameter of the accommodating hole 1A, and a first small diameter portion 15 provided on one end side (support portion 20 side, left side in the figure) of the first small diameter portion 15. A second small diameter portion 16 having an outer diameter smaller than that of the portion 15 is formed. An annular space 6 is formed between the first small diameter portion 15 and the accommodating hole 1A.

The support portion 20 is housed inside the cap 30. The support portion 20 has a shaft portion 21 attached to a second small diameter portion 16 at one end of the main body portion 11 by screw fastening, and a head portion 22 having an outer diameter larger than that of the shaft portion 21. That is, the support portion 20 is detachably attached to the main body portion 11.

The shaft portion 21 has substantially the same outer diameter as the second small diameter portion 16 of the main body portion 11, and is coaxially attached to the second small diameter portion 16. A slit 23 extending in the radial direction is formed on the end surface of the head portion 22.

The cap 30 communicates with a large-diameter hole 31 through which the spool 10 can enter the accommodating hole 1A, a small-diameter hole 32 with a communication with the large-diameter hole 31 and a smaller inner diameter than the large-diameter hole 31, and a communication with the large-diameter hole 31. Pilot port 55 and the like are formed. The pilot pressure chamber 50 is formed by the small diameter hole 32 and the large diameter hole 31. The head portion 22 of the support portion 20 enters the small diameter hole 32.

The spring 35 is provided on the outer periphery of the shaft portion 21 of the support portion 20, and both ends thereof are supported by a pair of spring seats 60 and 65. One spring seat 60 is seated on the stepped surface 22A between the shaft portion 21 and the head portion 22, and the other spring seat 65 is seated on the end surface 1B of the housing 1 to which the cap 30 is attached. As the spring 35 expands and contracts (movement of the spool 10), one spring seat 60 moves relative to the other spring seat 65 along the axial direction of the spool 10. The spring 35 is interposed between the pair of spring seats 60 and 65 in a compressed state. Therefore, the spring 35 exerts an urging force to move the spool 10 in the direction (left direction in the figure) in which the inflow passage 2A and the outflow passage 2B communicate with each other.

The pair of spring seats 60 and 65 are formed to have the same shape. One spring seat 60 has a disc-shaped flange portion 61 in contact with the stepped surface 31A between the large diameter hole 31 and the small diameter hole 32 of the cap 30, and a shaft from the flange portion 61 toward the other spring seat 65. It has a tubular boss portion 62 extending in the direction and a tubular boss portion 62. The inner diameter of the flange portion 61 is formed to be smaller than the outer diameter of the head portion 22. A slit 61A extending in the radial direction is formed on the end surface of the flange portion 61 in contact with the stepped surface 31A between the large diameter hole 31 and the small diameter hole 32.

The other spring seat 65 has a disc-shaped flange portion 66 in contact with the end surface 1B of the housing 1 and a cylindrical boss portion 67 extending axially from the flange portion 66 toward one spring seat 60. .. A slit 66A extending in the radial direction is formed on the end surface of the flange portion 66 in contact with the end surface 1B of the housing 1.

The switching portion 40 is screwed into the screw hole 33 formed in the cap 30 and regulates a change in the screwing position of the switching bolt 41 that advances and retreats with respect to the spool 10 by manual operation and the switching bolt 41 with respect to the screw hole 33. It has a regulating nut 45 and. The screw hole 33 is formed in the cap 30 so as to communicate with the pilot pressure chamber 50 (small diameter hole 32).

The switching bolt 41 has a screw portion 42 screwed into the screw hole 33, a contact portion 43 that comes into contact with the head portion 22 of the spool 10 from the axial direction, and an operation portion 44 operated by an operator. The contact portion 43 is housed in the small diameter hole 32. A part of the screw portion 42 protrudes to the outside of the cap 30, and an operation portion 44 is provided at the end of the protruding screw portion 42. When the operator grips and rotates the operation portion 44, the screwing position of the screw portion 42 with respect to the screw hole 33 is adjusted.

The regulating nut 45 is screwed into the threaded portion 42 exposed to the outside of the cap 30. By tightening the restricting nut 45 screwed into the switching bolt 41 to the cap 30, the change in the screwing position of the switching bolt 41 with respect to the screw hole 33 of the cap 30 is restricted. On the contrary, by loosening the regulation nut 45 to create a gap between the regulation nut 45 and the cap 30, the screwing position of the switching bolt 41 with respect to the screw hole 33 of the cap 30 can be adjusted, and the switching bolt 41 can be used. It is possible to move forward and backward with respect to the spool 10.

The control valve 100 further includes a drain passage 70 for releasing the pressure of the pilot pressure chamber 50, and a throttle portion provided in the drain passage 70 to impart resistance to the flow of hydraulic oil passing through the drain passage 70.

The drain passage 70 is formed inside the spool 10. The drain passage 70 has an axial passage 71 that passes through the axis of the main body 11 of the spool 10 and always communicates with the tank port 2C formed in the housing 1, and an annular space 6 on the outer periphery of the first small diameter portion 15 in the axial direction. It has a throttle passage 72 as a throttle portion that communicates with the passage 71 and has a flow resistance larger than that of the axial passage 71. The axial passage 71 opens at the end surface of the main body 11 of the spool 10. The axial passage 71 always communicates with the tank port 2C through the space (a part of the accommodating hole 1A) between the main body 11 and the bottom of the accommodating hole 1A. Further, the pilot pressure chamber 50 always communicates with the annular space 6 through the slit 66A of the flange portion 66 of the other spring seat 65. Therefore, the pilot pressure chamber 50 always communicates with the tank T through the drain passage 70 and the tank port 2C regardless of the position of the control valve 100 (the position of the spool 10).

Next, the operation of the control valve 100 will be described.

The position of the control valve 100 is switched by adjusting the screwing position of the switching bolt 41 of the switching unit 40. Hereinafter, the state in which the inflow passage 2A and the outflow passage 2B communicate with each other is referred to as a “communication position”, and the state in which the inflow passage 2A and the outflow passage 2B are cut off is referred to as a “blocking position”.

When switching the control valve 100 from the communication position (FIG. 1) to the shutoff position (FIG. 2), the regulation nut 45 is loosened and the switching bolt 41 is rotated so as to move toward the spool 10. As a result, the spool 10 is pressed by the switching bolt 41 and moves against the urging force of the spring 35. Further, as the spool 10 moves against the urging force of the spring 35, it is pressed by the step surface 22A between the shaft portion 21 and the head portion 22, and one spring seat 60 also moves toward the other spring seat 65. do.

The spool 10 moves against the urging force of the spring 35 until the boss portions 62 and 67 of the pair of spring seats 60 and 65 come into contact with each other. In other words, the contact between the pair of spring seats 60 and 65 restricts the movement of the spool 10 against the urging force of the spring 35. When the spool 10 moves until the pair of spring seats 60 and 65 come into contact with each other, the second land portion 13 cuts off the communication between the inflow passage 2A and the outflow passage 2B. In this state, the regulation nut 45 is tightened to regulate the change in the screwing position of the switching bolt 41. In this way, the control valve 100 is switched to the shutoff position.

On the other hand, when switching the control valve 100 from the shutoff position to the communication position, the regulation nut 45 is loosened and the switching bolt 41 is rotated so as to be separated from the spool 10. As a result, the spool 10 receives the urging force of the spring 35 and moves together with the one spring seat 60 so as to follow the switching bolt 41 separated from the spool 10. The spool 10 moves under the urging force of the spring 35 until the spring seat 60 abuts on the stepped surface 31A between the large diameter hole 31 and the small diameter hole 32. When the spring seat 60 moves until it comes into contact with the stepped surface 31A between the large-diameter hole 31 and the small-diameter hole 32, the inflow passage 2A and the outflow passage 2B communicate with each other through the fluid chamber 5, as shown in FIG. In this state, the regulation nut 45 is tightened to regulate the change in the screwing position of the switching bolt 41. In this way, the control valve 100 is switched to the communication position.

In this way, the control valve 100 can switch the position by manually operating the switching bolt 41 of the switching unit 40.

Here, in general, a fluid pressure control device incorporating a control valve that can be switched by manual operation may be inspected at the time of shipment by an automatic inspection line in an inspection process at the time of manufacture. However, when the manually operated control valve is incorporated in the fluid pressure control device, the operation check of the control valve needs to be manually performed by the operator separately from the inspection by the automatic inspection line. Further, when the space around the switching portion of the control valve is small, it becomes difficult to operate the switching portion, and a large number of man-hours are required in the process of confirming the operation of the control valve. In this way, there are cases where even a manually operated control valve is desired to be operated by an external signal, such as when the operation is confirmed by an automatic inspection line together with the fluid pressure control device. However, in a manual control valve, the inside of the cap needs to communicate with the tank in order to prevent malfunction due to the pressure buildup inside the cap. Therefore, even if the pilot pressure is supplied to the inside of the cap, the pilot pressure does not act on the spool, and it is difficult to move the spool.

On the other hand, in the control valve 100, since the throttle passage 72 is provided in the drain passage 70, the pilot pressure chamber 50 communicates with the tank T, but resistance is given to the hydraulic oil passing through the throttle passage 72. Therefore, the pressure of the pilot pressure chamber 50 does not drop to the tank pressure due to the resistance of the throttle passage 72, and the predetermined pressure is maintained. As a result, when the pilot pressure is supplied to the pilot pressure chamber 50 in the state where the control valve 100 is in the communication position, the pressure equal to or higher than the tank pressure is applied to the slit 23 of the head portion 22 through the slit 61A in the flange portion 61 of one spring seat 60. It works. The pressure acting on the head portion 22 urges the spool 10 against the urging force of the spring 35. Therefore, as shown in FIG. 3, while the pilot pressure is being supplied to the pilot pressure chamber 50, the control valve 100 is switched to the shutoff position by the pressure generated in the pilot pressure chamber 50. When the supply of the pilot pressure to the pilot pressure chamber 50 is stopped, the pressure in the pilot pressure chamber 50 is discharged to the tank T through the drain passage 70. Therefore, the spool 10 moves under the urging force of the spring 35 and is switched to the communication position.

As described above, the control valve 100 can switch the position by the pilot pressure in addition to the position switching by the manual operation. Therefore, the operation of the switching valve can be confirmed by the automatic inspection line, and the man-hours required for the inspection process can be reduced. The operation of the control valve 100 by the pilot pressure of the pilot pressure chamber 50 is not limited to the case of inspection in the automatic inspection line, and may be executed in other situations.

Next, a modification of the present embodiment will be described.

In the above embodiment, the control valve 100 is switched from the communication position to the shutoff position by supplying the pilot pressure to the pilot pressure chamber 50. On the other hand, the control valve 100 may be switched from the shutoff position to the communication position by supplying the pilot pressure to the pilot pressure chamber 50.

Further, in the above embodiment, the drain passage 70 is formed on the spool 10. On the other hand, the drain passage 70 may be formed in the housing 1 or the cap 30.

Further, in the above embodiment, the throttle portion is a throttle passage 72 having a flow resistance larger than that of the other drain passage 70 (axial passage 71). On the other hand, the throttle portion may be an orifice plug that is detachably attached to the drain passage 70.

According to the above embodiment, the following effects are obtained.

In the manually operated control valve 100, a throttle passage 72 is provided in the drain passage 70 for releasing the pressure of the pilot pressure chamber 50. As a result, when the pilot pressure is supplied to the pilot pressure chamber 50, a pressure larger than the tank pressure is generated in the pilot pressure chamber 50 due to the resistance of the throttle passage 72. Therefore, the spool 10 can be moved by this pressure. As described above, according to the control valve 100, not only the manual operation is possible, but also the automatic operation is possible by the signal from the outside.

Since the control valve 100 can be manually operated and automatically operated, the operation of the control valve 100 can be confirmed by an automatic inspection line, and an inspection step in manufacturing a fluid pressure control device provided with the control valve 100 and the control valve 100. Can be easily carried out.

Further, in the control valve 100, the movement of the spool 10 is restricted by the contact between the pair of spring seats 60 and 65. The spring seat 65 is provided with a boss portion 67 on the outer periphery of the second small diameter portion 16 of the spool 10 and the shaft portion 21 of the support portion 20. By configuring the control valve 100 in this way, the stroke amount of the spool 10 can be changed by changing the axial length of the second small diameter portion 16. Therefore, even if the control valve 100 moves with a different stroke amount, the spring seats 60 and 65 and the support portion 20 can be used in common, and the manufacturing cost of the control valve 100 can be reduced.

Hereinafter, the configurations, actions, and effects of the embodiments of the present invention will be collectively described.

The control valve 100 that controls the flow of hydraulic oil includes a housing 1, a storage hole 1A formed in the housing 1 that opens into the end surface 1B of the housing 1, and a spool 10 that is slidably inserted into the storage hole 1A. A cap 30 for sealing the opening of the hole 1A, a spring 35 for urging the spool 10 in one direction, and a switching unit provided on the cap 30 to move the spool 10 against the urging force of the spring 35 by manual operation. 40, a pilot pressure chamber 50 formed inside the cap 30 to guide the pilot pressure for urging the spool 10 against the urging force of the spring 35, and a pilot pressure chamber 50 formed in the cap 30 to guide the pilot pressure to the pilot pressure chamber 50. It includes a pilot port 55, a drain passage 70 for releasing the pressure of the pilot pressure chamber 50, and a throttle passage 72 provided in the drain passage 70 to impart resistance to the flow of hydraulic oil passing through the drain passage 70.

Further, in the control valve 100, the switching portion 40 is a switching bolt 41 that is screwed into the screw hole 33 formed in the cap 30 and advances and retreats with respect to the spool 10 by manual operation.

In these configurations, a drain passage 70 for releasing the pressure of the pilot pressure chamber 50 is provided, and a throttle passage 72 is provided in the drain passage 70. When the pilot pressure is guided to the pilot pressure chamber 50, a part of the hydraulic oil in the pilot pressure chamber 50 is discharged through the drain passage 70, but resistance is applied by the throttle passage 72, so that the pilot pressure chamber 50 is predetermined. Pressure is generated. Therefore, by supplying the pilot pressure to the pilot pressure chamber 50, a thrust for moving the spool 10 in the pilot pressure chamber 50 is generated, and the spool 10 can be moved. Therefore, the control valve 100 is operated not only by manual operation but also by pilot pressure.

The control valve 100 is provided in the cap 30 and further includes a pair of spring seats 60 and 65 in which both ends of the spring 35 are seated and move relative to each other as the spring 35 expands and contracts, and the pair of spring seats 60 and 65 hit each other. By contacting the spool 10, the movement of the spool 10 against the urging force of the spring 35 is restricted.

In this configuration, since the movement of the spool 10 can be restricted by the spring seats 60 and 65, the movement amount of the spool 10 can be easily adjusted by changing the spring seats 60 and 65.

Although the embodiments of the present invention have been described above, the above-described embodiments show only a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above-described embodiments. do not have.

1 ... Housing, 1A ... Accommodating hole, 10 ... Spool (valve body), 30 ... Cap, 33 ... Screw hole, 35 ... Spring (biasing member), 40 ... Switching part, 41 ... Switching bolt, 50 ... Pilot pressure chamber , 55 ... pilot port, 60, 65 ... spring seat (seating member), 70 ... drain passage, 72 ... throttle passage (throttle portion), 100 ... control valve

Claims (5)

A control valve that controls the flow of working fluid.
With the housing
A housing hole formed in the housing and opened at the end face of the housing,
A valve body slidably inserted into the accommodating hole and
A cap that seals the opening of the accommodation hole and
An urging member that urges the valve body in one direction,
A switching unit provided on the cap to move the valve body against the urging force of the urging member by manual operation.
A pilot pressure chamber formed inside the cap and in which a pilot pressure for urging the valve body is guided against the urging force of the urging member.
A pilot port formed on the cap and guiding the pilot pressure to the pilot pressure chamber,
A drain passage that releases the pressure in the pilot pressure chamber to the tank ,
A control valve provided with a throttle portion provided in the drain passage and imparting resistance to the flow of a working fluid passing through the drain passage. The drain passage always communicates the pilot pressure chamber and the tank with each other.
The control valve according to claim 1, wherein the communication opening degree of the drain passage to the tank is constant regardless of the stroke position of the valve body. The control valve according to claim 1 or 2 , wherein the switching portion has a switching bolt that is screwed into a screw hole formed in the cap and advances and retreats with respect to the valve body by a manual operation. A pair of seating members provided in the cap, in which both ends of the urging member are seated and move relative to each other as the urging member expands and contracts, are further provided.
The control according to any one of claims 1 to 3, wherein when the pair of seating members come into contact with each other, the movement of the valve body against the urging force of the urging member is restricted. valve. One of the pair of seating members has a flange portion that comes into contact with the end face of the housing.
The control valve according to claim 4, wherein a slit is formed in the end surface of the flange portion in contact with the end surface of the housing so that the pilot pressure chamber and the drain passage are always communicated with each other.

Images