JP2020070904A - Control valve - Google Patents

Abstract

To provide a control valve which enables manual operation and automatic operation.SOLUTION: A control valve 100 includes: a housing hole 1A formed at a housing 1 and opening on an end surface of the housing 1; a spool 10 which is slidably inserted into the housing hole 1A; a cap 30 which seals an opening of the housing hole 1A; a spring 35 which biases the spool 10 in one direction; a switch part 40 which is provided at the cap 30 and moves the spool 10 against biasing force of the spring 35 by manual operation; a pilot pressure chamber 50 which is formed within the cap 30 and into which a pilot pressure for biasing the spool 10 against the biasing force of the spring 35 is introduced; a drain passage 70 which releases pressure of the pilot pressure chamber 50; and a contracted passage 72 which is provided at the drain passage 70 and provides resistance to flow of a working fluid passing therethrough.SELECTED DRAWING: Figure 1

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).

JP-A-6-227789

  In the manual control valve of Patent Document 1, a valve body is housed in a housing hole that opens at an end of a housing, and a cap is provided to close the opening of the housing hole. A spring for urging the valve element toward one side is provided inside the cap. The position of the control valve is switched by manually moving the valve body against the biasing force of the spring.

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

  As a method of operating the control valve by a signal from the outside, for example, supplying pilot pressure to the inside of the cap to move the valve body can be considered. However, manual control valves are generally configured to drain the pressure within the cap through a drain passage that communicates with the tank. Therefore, even if the pilot pressure is introduced into the cap, the urging force for moving the valve element 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 a signal from the outside.

  The present invention relates to a control valve for controlling the flow of a working fluid, including a housing, a housing hole formed in the housing and opening to an end surface of the housing, a valve body slidably inserted into the housing hole, and a housing hole. A cap that seals the opening of the valve, a biasing member that biases the valve element in one direction, a switching unit that is provided on the cap and moves the valve element against the biasing force of the biasing member by manual operation, A pilot pressure chamber that is formed inside the cap and that guides the pilot pressure that biases the valve body against the biasing force of the biasing member; a pilot port that is formed in the cap that guides the pilot pressure to the pilot pressure chamber; A drain passage for releasing the pressure in the chamber, and a throttle portion provided in the drain passage for imparting resistance to the flow of the working fluid passing therethrough are provided.

  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 is moved forward and backward with respect to the valve body by a manual operation.

  In these inventions, the drain passage for releasing the pressure in the pilot pressure chamber is provided, and the throttle portion is provided in the drain passage. When the pilot pressure is introduced into 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 that are provided in the cap, and that both ends of the biasing member are seated and relatively move as the biasing member expands and contracts. It is characterized in that the movement of the valve body against the biasing force of the member is restricted.

  In this invention, since the movement of the valve element can be restricted by the seating member, the amount of movement of the valve element can be easily adjusted by changing the seating member.

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

It is a sectional view of a control valve concerning an embodiment of the present invention, and is a figure showing the state where it is in a communicating position. It is a sectional view of a control valve concerning an embodiment of the present invention, and is a figure showing the state of being in a shut-off position. It is a sectional view of a control valve concerning an embodiment of the present invention, and is a figure showing the state changed to the interception position by pilot pressure.

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

  The control valve 100 is used for 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). It controls the flow of. In the following embodiments, the case where the working fluid is working oil will be described. The working fluid is not limited to working oil, and may be other non-compressible fluid or compressible fluid.

  The control valve 100 is a two-position control valve that is switched between two positions by the movement of the spool 10. As shown in FIG. 1, the control valve 100 includes a housing 1, a housing hole 1A formed in the housing 1 and opening to an end surface 1B of the housing 1, and a spool as a valve body slidably inserted into the housing hole 1A. 10, a cap 30 for sealing the opening of the accommodation hole 1A, a spring 35 as a biasing member provided in the cap 30 for biasing the spool 10 in one direction, and a spring provided by the cap 30 and manually operated. A switching portion 40 for moving the spool 10 against the urging force of the spool 35, and a pilot pressure chamber 50 formed inside the cap 30 for guiding a pilot pressure for urging the spool 10 against the urging force of the spring 35. , A pilot port 55 that is formed in the cap 30 and guides pilot pressure to the pilot pressure chamber 50, and a spring 35 that is provided in the cap 30 End is seated comprises a spring seat 60, 65 as a pair of seat members which relatively move with the expansion and contraction of the spring 35.

  An inflow passage 2A and an outflow passage 2B through which hydraulic oil flows are formed in the housing 1 side by side in the axial direction. The inflow passage 2A communicates with the accommodation hole 1A and communicates with a fluid pressure supply source via a pipe or the like (not shown). The outflow passage 2B communicates with the accommodation hole 1A and communicates with a hydraulic device or the like via a pipe or the like not shown. A tank port 2C communicating with the tank T is formed at the bottom of the accommodation hole 1A. The tank port 2C guides the hydraulic oil, which is introduced between the bottom of the accommodation 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 accommodation hole 1A, and a support portion 20 that is attached to one end (the left end in the figure) 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 and the first land portion 12 and the second land portion 13 that slide along the inner peripheral surface of the accommodation hole 1A. And 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 accommodation hole 1A. The fluid chamber 5 communicates with the inflow passage 2A and the outflow passage 2B as the spool 10 moves, and guides the hydraulic oil that has passed through the inflow passage 2A to the outflow passage 2B.

  A first small-diameter portion 15 having an outer diameter smaller than the inner diameter of the accommodation hole 1A is provided at one end of the main body portion 11, and a first small-diameter portion is provided at one end side of the first small-diameter portion 15 (support portion 20 side, left side in the drawing). 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 accommodation hole 1A.

  The support portion 20 is housed inside the cap 30. The support portion 20 has a shaft portion 21 attached to the 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 has a large-diameter hole 31 that communicates with the accommodation hole 1A and allows the spool 10 to enter, a small-diameter hole 32 that communicates with the large-diameter hole 31 and has an inner diameter smaller than that of the large-diameter hole 31, and communicates with the large-diameter hole 31. And a pilot port 55 that operates. The small diameter hole 32 and the large diameter hole 31 form a pilot pressure chamber 50. The head portion 22 of the support portion 20 enters the small diameter hole 32.

  The spring 35 is provided on the outer circumference of the shaft portion 21 of the support portion 20, and both ends thereof are supported by the pair of spring seats 60 and 65. One spring seat 60 is seated on the step surface 22A between the shaft part 21 and the head part 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. With the expansion and contraction of the spring 35 (movement of the spool 10), the 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 that moves the spool 10 in a direction (left direction in the drawing) that connects the inflow passage 2A and the outflow passage 2B.

  The pair of spring seats 60 and 65 are formed in the same shape. One of the spring seats 60 has a disc-shaped flange portion 61 that comes into contact with a step surface 31A between the large diameter hole 31 and the small diameter hole 32 of the cap 30, and a shaft extending from the flange portion 61 toward the other spring seat 65. And a cylindrical boss portion 62 extending in the direction. The inner diameter of the flange portion 61 is formed 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 that contacts the step 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 that contacts the end surface 1B of the housing 1, and a cylindrical boss portion 67 that extends axially from the flange portion 66 toward the one spring seat 60. .. A slit 66 </ b> A extending in the radial direction is formed on the end surface of the flange portion 66 that contacts the end surface 1 </ b> B 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 with respect to the screw hole 33 and the switching bolt 41 that moves forward and backward with respect to the spool 10 by a manual operation. And a restriction nut 45. 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 that is screwed into the screw hole 33, a contact portion 43 that axially contacts the head portion 22 of the spool 10, and an operation portion 44 that is 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 operating portion 44 is provided at the end of the protruding screw portion 42. The screwing position of the screw portion 42 with respect to the screw hole 33 is adjusted by the operator gripping and rotating the operation portion 44.

  The restriction nut 45 is screwed into the screw portion 42 exposed on the outside of the cap 30. When the restriction nut 45 screwed to the switching bolt 41 is tightened to the cap 30, the change of 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 and creating 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 is The spool 10 can be moved back and forth.

  The control valve 100 further includes a drain passage 70 that allows the pressure in the pilot pressure chamber 50 to escape, and a throttle portion that is provided in the drain passage 70 and that imparts resistance to the flow of hydraulic oil passing therethrough.

  The drain passage 70 is formed inside the spool 10. The drain passage 70 passes through the axial center of the main body portion 11 of the spool 10 and is in continuous communication with the tank port 2C formed in the housing 1, and the annular space 6 on the outer periphery of the first small diameter portion 15 and the axial direction. A throttle passage 72, which is a throttle portion that communicates the passage 71 and has a larger flow passage resistance than 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 a space (a part of the accommodation hole 1A) between the main body 11 and the bottom of the accommodation 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 is always in communication with the tank T through the drain passage 70 and the tank port 2C regardless of the position of the control valve 100 (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, a state in which the inflow passage 2A and the outflow passage 2B communicate with each other is referred to as a "communication position", and a state in which the inflow passage 2A and the outflow passage 2B communicate with each other is referred to as a "blocking position".

  When switching the control valve 100 from the communicating position (FIG. 1) to the shut-off position (FIG. 2), the regulating 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 biasing force of the spring 35. Further, with the movement of the spool 10 against the biasing force of the spring 35, the one spring seat 60 is also moved toward the other spring seat 65 by being pressed by the step surface 22A between the shaft portion 21 and the head portion 22. To do.

  The spool 10 moves against the biasing 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 abutment of the pair of spring seats 60, 65 restricts the movement of the spool 10 against the biasing 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 communication between the inflow passage 2A and the outflow passage 2B is blocked by the second land portion 13, 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 shut-off position.

  On the other hand, when the control valve 100 is switched from the shutoff position to the communication position, the restriction 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 biasing 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 biasing force of the spring 35 until the spring seat 60 contacts the step 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 step 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, in a fluid pressure control device in which a control valve that is switched by a manual operation is incorporated, an inspection at the time of shipment may be performed by an automatic inspection line in an inspection process at the time of manufacturing. 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 performed manually by an operator in addition to 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 lot of man-hours are required for the step of checking the operation of the control valve. As described above, there are cases where it is desired to operate a control valve that is manually operated by a signal from the outside even when the operation is confirmed by an automatic inspection line together with the fluid pressure control device. However, in the case of a manual control valve, the inside of the cap needs to be communicated with the tank in order to prevent a malfunction due to the accumulation of pressure 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 imparted to the hydraulic oil passing through the throttle passage 72. Therefore, the pressure in the pilot pressure chamber 50 does not decrease to the tank pressure due to the resistance of the throttle passage 72, and the predetermined pressure is maintained. As a result, when pilot pressure is supplied to the pilot pressure chamber 50 with the control valve 100 in the communication position, a pressure equal to or higher than the tank pressure is applied to the slit 23 of the head portion 22 through the slit 61A of the flange portion 61 of the one spring seat 60. To work. 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 shut-off position by the pressure generated in the pilot pressure chamber 50. When the supply of 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 is moved by receiving the biasing force of the spring 35, and is switched to the communication position.

  In this way, 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 number of steps 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 performing the inspection in the automatic inspection line, and may be executed in other situations.

  Next, a modified example of the present embodiment will be described.

  In the above embodiment, by supplying the pilot pressure to the pilot pressure chamber 50, the control valve 100 is switched from the communication position to the cutoff position. On the other hand, the control valve 100 may be switched from the shut-off 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 in 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 the throttle passage 72 having a larger flow passage resistance than the other drain passage 70 (axial passage 71). On the other hand, the throttle portion may be an orifice plug detachably attached to the drain passage 70.

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

  In the manually operated control valve 100, a throttle passage 72 is provided in the drain passage 70 that allows the pressure in the pilot pressure chamber 50 to escape. 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 manual operation but also automatic operation by a signal from the outside is possible.

  Since the control valve 100 can be operated manually and automatically, the operation of the control valve 100 can be confirmed by an automatic inspection line, and the inspection process in the manufacture of the control valve 100 and the fluid pressure control device provided with the control valve 100. Can be easily implemented.

  Further, in the control valve 100, the movement of the spool 10 is restricted by the pair of spring seats 60 and 65 contacting each other. In the spring seat 65, the boss portion 67 is provided 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 in the control valve 100 that moves with different stroke amounts, the spring seats 60 and 65 and the support portion 20 can be commonly used, and the manufacturing cost of the control valve 100 can be reduced.

  Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be collectively described.

  The control valve 100 for controlling the flow of hydraulic oil includes a housing 1, a housing hole 1A formed in the housing 1 and opening to an end surface 1B of the housing 1, a spool 10 slidably inserted in the housing hole 1A, and a housing A cap 30 that seals the opening of the hole 1A, a spring 35 that biases the spool 10 in one direction, and a switching unit that is provided on the cap 30 and that moves the spool 10 by a manual operation against the biasing force of the spring 35. 40, a pilot pressure chamber 50 formed inside the cap 30 to which pilot pressure for biasing the spool 10 against the biasing force of the spring 35 is guided, and a pilot pressure chamber formed in the cap 30 to pilot pressure chamber 50. The pilot port 55, the drain passage 70 that releases the pressure of the pilot pressure chamber 50, and the hydraulic oil that is provided in the drain passage 70 Includes a throttle passage 72 that confers resistance to Les, the.

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

  In these configurations, the drain passage 70 for releasing the pressure of the pilot pressure chamber 50 is provided, and the throttle passage 72 is provided in the drain passage 70. When the pilot pressure is introduced into 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 imparted by the throttle passage 72, so that the pilot pressure chamber 50 has a predetermined pressure. 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 operates not only by manual operation but also by pilot pressure.

  The control valve 100 further includes a pair of spring seats 60 and 65 which are provided in the cap 30 and in which both ends of the spring 35 are seated and which move relative to each other as the spring 35 expands and contracts. By the contact, the movement of the spool 10 against the biasing 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 embodiment of the present invention has been described above, the above embodiment merely shows a part of the application example of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  DESCRIPTION OF SYMBOLS 1 ... Housing, 1A ... Storage 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 (3)

A control valve for controlling the flow of working fluid,
Housing,
A housing hole formed in the housing and opening at an end surface of the housing;
A valve body slidably inserted into the accommodation hole,
A cap for sealing the opening of the accommodation hole,
A biasing member for biasing the valve element in one direction,
A switching unit that is provided on the cap and moves the valve element against the urging force of the urging member by a manual operation;
A pilot pressure chamber, which is formed inside the cap, and into which a pilot pressure for urging the valve body is urged against the urging force of the urging member;
A pilot port formed in the cap for guiding pilot pressure to the pilot pressure chamber;
A drain passage for releasing the pressure in the pilot pressure chamber,
A control valve provided in the drain passage, which restricts flow of a working fluid passing therethrough.   The control valve according to claim 1, wherein the switching portion has a switching bolt that is screwed into a screw hole formed in the cap and that moves forward and backward with respect to the valve body by a manual operation. Further comprising a pair of seating members that are provided in the cap and that both ends of the biasing member are seated and that move relative to each other as the biasing member expands and contracts,
The control valve according to claim 1 or 2, wherein movement of the valve body against the biasing force of the biasing member is restricted by the pair of seating members contacting each other.

Images