JP2012017796A - Relief valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a relief valve which can damp sound and vibration caused when a member constituting the relief valve abuts on the other members in operation.SOLUTION: The relief valve includes: a valve body 2 having a first port 11 and a second port 12; a sleeve 4 which is received in the valve body 2 and has an inlet port 7 communicating with the first port 11 and a discharge port 8 communicating with the second port 12; a valve 5 which is received in the sleeve 4 and prohibits the communication between the inlet port 7 and the discharge port 8 when the valve is moved to the inlet port 7 side while permitting the communication between the inlet port 7 and the discharge port 8 when the valve is moved to the side opposite to the inlet port 7; an energizing member 6 for energizing the valve 5 to the inlet port 7 side; a valve position changing mechanism 13 for changing the relative position of the valve body 2 to the sleeve 4 and to the valve 5; and a plug 3 which is supported and fixed to the valve body 2 through an elastic member 16 and abuts on the end 4b of the sleeve 4 when the sleeve 4 moves to the sliding end point opposite to the inlet port 7.

Description

  The present invention relates to a relief valve, and more particularly to a relief valve capable of changing a valve opening pressure used for adjusting hydraulic pressure of an engine lubrication system.

When the pressure in the hydraulic circuit becomes equal to or higher than a set pressure, the relief valve suppresses an increase in pressure in the hydraulic circuit by opening an excess oil relief passage provided in the relief valve.
This type of relief valve is, for example, a body, a valve, a spring, a retainer, a plug, an oil passage for introducing oil between the retainer and the plug, and a back pressure control valve for controlling oil introduction, as in Non-Patent Document 1. Composed.
In this relief valve, when oil is not introduced between the retainer and the plug, the retainer is positioned at the plug end face and the spring length is set longer, so that the oil discharged by the oil pump is more upstream in the oil flow direction than the relief valve. The valve opening pressure required for relief to the side is set to a low pressure. On the other hand, when oil is introduced between the retainer and the plug, the retainer rises to contract the spring, and the valve opening pressure is set to a high pressure.

Published technical report 2006-505946

  In this type of relief valve, sound and vibration are generated by the impact when the retainer moves and comes into contact with the plug, and the sound and vibration are transmitted to the valve body via the plug and further to other parts. There was a risk of transmission. Further, even after the contact, the sound and vibration may occur continuously due to oil pulsation caused by the oil pump. Since such sounds and vibrations cause discomfort to the user and may adversely affect other parts, it is desirable to reduce them as much as possible.

  The present invention has been made in view of the above problems, and provides a relief valve capable of attenuating sound and vibration generated by contact of other members when a member constituting the relief valve is operated. With the goal.

  The first characteristic configuration of the relief valve according to the present invention includes a valve body having a first port and a second port, an inflow port accommodated in the valve body, and communicated with the first port, and the second port. A sleeve having a discharge port communicating with the inlet, and being accommodated in the sleeve and moving to the inflow port side to prohibit communication between the inflow port and the discharge port, and moving to the opposite side of the inflow port A valve that permits communication between the inlet and the outlet, a biasing member that biases the valve toward the inlet, and a valve that changes a relative position between the valve body, the sleeve, and the valve. A position changing mechanism is supported and fixed to the valve body via an elastic member, and when the sleeve moves to the sliding end opposite to the inflow port, the end of the sleeve abuts. It lies in the fact that with a plug that, a.

  According to this configuration, the relative position between the valve body, the sleeve, and the valve is changed by the valve position changing mechanism. That is, it has the state of the 1st state which the sleeve moved to the 1st port side of the valve body with the valve, and the 2nd state which moved to the opposite side to the 1st port side.

  When the sleeve is in the first state, the position of the discharge port provided in the sleeve also moves to the first port side. At this time, since the valve is also moved to the first port side together with the sleeve, the urging member that urges the valve is in an extended state. Therefore, even if the fluid pressure from the first port is low, the biasing member that biases toward the first port is pushed back to the opposite side of the first port, and the valve opens the discharge port to the sleeve. . As a result, the first port and the second port communicate with each other, so that the excess liquid of the fluid on the first port side is drained. Therefore, the valve opening pressure of the relief valve is set to a low pressure when in the first state.

  On the other hand, when the sleeve is in the second state, the position of the discharge port provided in the sleeve moves to the side opposite to the first port side. At this time, since the valve is also moved together with the sleeve to the side opposite to the first port side, the urging member that urges the valve is in a contracted state. Therefore, when the fluid pressure from the first port is low, the urging member that urges the first port is not pushed back to the side opposite to the first port, and the valve does not open the discharge port of the sleeve. When the fluid pressure from the first port becomes high, the biasing member that biases toward the first port is pushed back to the side opposite to the first port, and the valve opens the discharge port of the sleeve. As a result, the first port and the second port communicate with each other, so that the excess liquid of the fluid on the first port side is drained. Therefore, the valve opening pressure of the relief valve is set to a high pressure in the second state.

  For example, when the relief valve according to the present invention is used in the engine oil supply path, when the engine oil is at a low temperature, the first port and the second port are set to the first state by setting the valve opening pressure to a low pressure. Communication with is easier to tolerate. That is, it becomes difficult to supply oil to other parts of the engine that require oil supply. However, when warming up the engine, for example, it is not necessary to immediately supply oil to the part that cools the piston or cylinder. Therefore, warming up can be performed efficiently with a small oil supply load. It can be carried out.

  Also, when the engine is running at a low speed (low load), the valve opening pressure is set to a low pressure in the first state. In this case, when the engine speed is low, there is little friction between members constituting the engine, and it may be less necessary to supply oil to the part. Therefore, when the engine is running at a low speed, oil can be supplied only to a predetermined location, for example, the friction of the oil pump can be reduced, and the engine can be operated efficiently.

  Further, according to the present configuration, the plug with which the end of the sleeve abuts when the sleeve moves to the sliding end point opposite to the inflow port is supported and fixed to the valve body via the elastic member. Therefore, since the sound and vibration generated when the sleeve comes into contact with the plug are attenuated by the elastic member when transmitted from the plug to the valve body, the influence of the sound and vibration can be reduced. Similarly, sound and vibration generated by the contact between the sleeve and the valve can also be attenuated by the elastic member when transmitted from the plug to the valve body.

  According to a second characteristic configuration of the relief valve of the present invention, a protrusion having a height smaller than the thickness of the elastic member is provided at the center of the bottom surface of the plug, and the annular elastic member is provided in the protrusion. It is at the point of fitting.

  According to this configuration, since the annular elastic member is fitted to the protruding portion provided at the center of the bottom surface of the plug, the elastic member can be easily positioned and the elastic member is uniformly arranged in the circumferential direction. Therefore, the inclination of the plug can be prevented. Moreover, since the height dimension of the protrusion is smaller than the thickness dimension of the elastic member, the protrusion can be prevented from coming into contact with the valve body.

  A third characteristic configuration of the relief valve according to the present invention is that the outer edge of the elastic member is located inside the outer edge of the bottom surface of the plug when the elastic member is compressed and deformed. .

  According to this configuration, since the entire area of the elastic member does not protrude from the area sandwiched between the bottom surface of the plug and the valve body, the elastic member is compressed and deformed in the area. The spring constant can be defined only by the hardness and thickness. Therefore, the elastic member can be easily selected according to the performance of the relief valve.

  A fourth characteristic configuration of the relief valve according to the present invention is that a seal ring is provided between the inner peripheral surface of the valve body and the outer peripheral surface of the plug.

  In the relief valve according to the present invention, since the plug is supported and fixed to the valve body via an elastic member, when a fluid such as oil flows between the bottom surface of the plug and the valve body and the fluid pressure rises, the plug May move away from the valve body. When such movement occurs, the valve opening pressure of the relief valve is different from the design value, which may cause a problem that appropriate relief is not performed. However, if a seal ring is provided between the inner peripheral surface of the valve body and the outer peripheral surface of the plug as in this configuration, fluid can be prevented from flowing between the bottom surface of the plug and the valve body. Occurrence can be avoided.

  In a fifth characteristic configuration of the relief valve according to the present invention, the valve position changing mechanism causes the fluid pressure of the fluid flowing through the first port to act on the sleeve to be in the same direction as the urging direction of the urging member. It is in the point to move to.

  Thus, in order to change the relative position of the valve body, the sleeve, and the valve, the fluid pressure of the fluid flowing through the first port is applied to the sleeve, so no additional power is required to move the sleeve, The relief valve structure can be simplified. Moreover, since the sleeve is moved in the same direction as the urging direction of the urging member, the fluid pressure of the fluid flowing through the first port and the urging force of the urging member can be efficiently applied to the sleeve.

  According to a sixth characteristic configuration of the relief valve of the present invention, the valve position changing mechanism causes the fluid pressure of the fluid flowing through the first port to act on the sleeve to be in the same direction as the biasing direction of the biasing member. It is in the point provided with OSV which switches whether to move to.

  In this way, in order to change the relative position of the valve body, the sleeve, and the valve, the fluid pressure of the fluid flowing through the first port is applied to the sleeve and moved in the same direction as the urging direction of the urging member. Since the OSV for switching whether or not is provided, the power for moving the sleeve is not required separately, and the structure of the relief valve can be simplified. Further, it is possible to reliably switch whether or not the fluid pressure of the fluid flowing through the first port acts on the sleeve by the OSV.

  According to a seventh characteristic configuration of the relief valve of the present invention, when the valve position changing mechanism is operated, the fluid is discharged from the discharge port by causing the fluid pressure of the fluid to act on the valve above the first valve opening pressure. When the valve position changing mechanism is not in operation, the fluid is discharged from the discharge port by causing the fluid pressure of the fluid to act on the valve at a second valve opening pressure or higher, and the second valve opening pressure is The fluid pressure is higher than the first valve opening pressure.

  With this configuration, when the valve position changing mechanism is operated, a low pressure setting is made so that the fluid pressure of the fluid in the valve is equal to or higher than the first valve opening pressure, and when the valve position changing mechanism is not operated, the fluid of the fluid in the valve When the pressure is equal to or higher than the second fluid pressure, which is a fluid pressure higher than the first valve opening pressure, the high pressure is set so as to relieve. In this way, it is possible to easily change the setting of the valve opening pressure in the relief valve.

  An eighth feature of the relief valve according to the present invention is that, of the both end faces of the sleeve, one end face faces the first port and the other end face faces the flow path of the valve position changing mechanism. The area of the other end face is set larger than the area of the one end face.

  With this configuration, when the hydraulic pressure of the first port is applied to the other end face, the fluid pressure acting on the other end face is larger than the pressing force due to the fluid pressure acting on one end face due to the difference in area of both end faces. The pressing force due to is increased, and the sleeve can be reliably positioned on the first port side with a simple configuration.

  A ninth feature of the relief valve according to the present invention is that a portion of the outer peripheral surface of the sleeve is formed with sliding surfaces with the valve body at both end portions of the sleeve and is sandwiched between the both end portions. Does not form the sliding surface.

  The sleeve of this configuration is changed in position using, for example, the fluid pressure of the first port. Therefore, it is desirable that the sliding resistance with respect to the valve body is as small as possible. Therefore, by distributing the sliding surface with the valve body to the vicinity of both ends of the sleeve, the area of the sliding surface during sliding is reduced, and the inclination of the sleeve is kept to a minimum. The generated frictional force is minimized.

  A tenth characteristic configuration of the relief valve according to the present invention is a first communication for discharging the fluid or air inside the sleeve out of the fluid or air on the opposite side of the first port across the valve. A hole is provided in the sleeve.

  With this configuration, when the position of the sleeve is changed by the valve position changing mechanism, the volume of the fluid or air on the side opposite to the first port side of the fluid or air inside the sleeve is increased or decreased across the valve. . At that time, by discharging the fluid or air on the opposite side, the fluid can freely enter and exit, and the resistance when the sleeve moves can be reduced.

  An eleventh characteristic configuration of the relief valve according to the present invention is a second communication that discharges the fluid or air inside the sleeve from the side opposite to the first port through the valve. A hole is provided in the valve.

  With this configuration, when the valve is pushed down by the fluid pressure from the first port, the fluid or air on the opposite side of the first port across the valve becomes a resistance. Therefore, the fluid or air communicates with the second port to facilitate the discharge of the fluid or air, thereby smoothing the valve operation.

It is a figure which shows embodiment (low pressure setting state) of the relief valve which concerns on this invention. It is a figure which shows embodiment (low pressure setting state) of the relief valve which concerns on this invention. It is a figure which shows embodiment (high pressure setting state) of the relief valve which concerns on this invention. It is a figure which shows embodiment (high pressure setting state) of the relief valve which concerns on this invention. It is sectional drawing which shows the shape of the elastic member of an uncompressed state. It is sectional drawing which shows the shape of the elastic member of a compression state. It is sectional drawing which shows the shape of the elastic member in other embodiment. It is sectional drawing which shows the shape of the elastic member in other embodiment. It is a figure which shows the relief valve in other embodiment. It is a figure which shows the relief valve in other embodiment.

  Hereinafter, as an embodiment of the present invention, a relief valve for controlling the pressure of a supply passage for supplying oil to an engine will be described with reference to the drawings.

  As shown in FIGS. 1 to 4, in the engine operating state, the oil (oil) stored in the oil pan 21 is sucked out by the oil pump 20 and directed to each lubricated member using the supply channel 10. And send it out. The relief valve 1 includes a valve body 2, a plug 3 supported and fixed to the valve body 2 via an elastic member 16, a cylindrical sleeve 4 that slides relative to the valve body 2 and the plug 3, A valve 5 that slides inside and a biasing member 6 (for example, a spring spring) that applies a biasing force to the valve 5 are provided, and are arranged in the path of the supply flow path 10.

  The valve body 2 includes a body main body 2A that accommodates the sleeve 4, the valve 5, and the like, and a plate member 2B that is fixed to the body main body 2A after the sleeve 4 and the valve 5 are assembled to the body main body 2A. The body main body 2A has a first port 11 through which a fluid flows and a second port 12 through which the fluid is discharged. The sleeve 4 includes an inlet 7 that communicates with the first port 11 and an outlet 8 that communicates with the second port 12. The valve 5 slides inside the sleeve 4 while receiving the pressure of the fluid through the inlet 7, closes the outlet 8 close to the inlet 7, and separated from the inlet 7. An open state in which the discharge port 8 is opened is formed. The biasing member 6 is configured to apply a biasing force in a direction in which the valve 5 resists the fluid pressure from the first port 11. In other words, the valve 5 prohibits communication between the inlet 7 and the outlet 8 by moving to the inlet 7 side, and moves to the opposite side of the inlet 7 by moving the inlet 5 to the inlet 7. Allow communication with.

  The relief valve 1 includes a valve position changing mechanism 13 that changes the relative position of the sleeve 4 with respect to the valve body 2. The valve position changing mechanism 13 is branched from the supply flow path 10 and connected to the side opposite to the first port 11 side of the sleeve 4 (hereinafter referred to as the anti-first port 11 side). And the OSV 15 that is provided in the path of the back pressure flow path 14 and turns on and off the action of the fluid pressure of the first port 11.

  When the OSV 15 is turned ON, as shown in FIGS. 1 and 2, the fluid in the supply flow path 10 is introduced from the back pressure flow path 14 to the side opposite to the first port 11 of the sleeve 4. The fluid pressure of the first port 11 acts in a direction against the fluid pressure from the first port 11. On the other hand, when the OSV 15 is turned OFF, as shown in FIGS. 3 and 4, the fluid in the supply flow path 10 is not introduced from the back pressure flow path 14 to the side opposite to the first port 11 of the sleeve 4. On the other hand, the fluid pressure of the first port 11 does not act in the direction against the fluid pressure from the first port 11.

  Of the two end faces 4 a and 4 b of the sleeve 4, one end face 4 a faces the first port 11, and the other end face 4 b faces the back pressure channel 14 of the valve position changing mechanism 13. Here, the area of the end face 4b is set larger than the area of the end face 4a. In this way, when the hydraulic pressure of the first port 11 is applied to the other end surface 4b, the other end surface 4b is compared with the pressing force applied to the one end surface 4a due to the difference in area between the both end surfaces 4a and 4b. Thus, the pressing force acting on the sleeve 4 becomes larger, and the sleeve 4 can be positioned on the first port 11 side. Therefore, the sleeve 4 can be positioned on the first port 11 side or the second port 12 side (the side opposite to the first port 11) by turning on / off the OSV 15.

  When the OSV 15 is turned on, the fluid pressure of the first port 11 acts on the sleeve 4 in a direction against the fluid pressure from the first port 11, and the sleeve 4 is moved toward the first port 11. When the sleeve 4 is positioned on the first port 11 side, the position of the discharge port 8 approaches the first port 11 side accordingly. Furthermore, since the valve 5 as well as the sleeve 4 is urged by the urging member 6 and is positioned on the first port 11 side, the urging member 6 is in an extended state. The urging member 6 in the extended state is easily pushed back to the side opposite to the first port 11. Therefore, even if the fluid pressure in the supply flow path 10 is low, the urging member 6 is pushed back to the side opposite to the first port 11 as shown in FIG. 2, and the valve 5 is separated from the inlet 7 of the sleeve 4. Thus, the discharge port 8 of the sleeve 4 is opened. Thus, the first port 11 and the second port 12 communicate with each other, and excess fluid (oil) returns to the suction port of the oil pump 20. That is, in this case, the valve opening pressure of the relief valve 1 is set to a low pressure (first valve opening pressure). In other words, when the OSV 15 (valve position changing mechanism 13) is operated, the fluid is discharged from the discharge port 8 by causing the fluid pressure of the fluid to act on the valve 5 at the first valve opening pressure or higher.

  On the other hand, when the OSV 15 is turned OFF, the fluid pressure of the first port 11 does not act on the sleeve 4 in the direction against the fluid pressure from the first port 11. Only the fluid pressure from the first port 11 acts on the sleeve 4, and the sleeve 4 is moved to the second port 12 side (the side opposite to the first port 11). When the sleeve 4 is positioned on the second port 12 side (the side opposite to the first port 11), the position of the discharge port 8 is also moved away from the first port 11 side. Further, since the valve 5 as well as the sleeve 4 is located on the second port 12 side (the side opposite to the first port 11), the biasing member 6 is in a contracted state. The biasing member 6 in the contracted state is hardly pushed back toward the first port 11 side. Therefore, when the fluid pressure in the supply channel 10 is low, the urging member 6 is not pushed back to the side opposite to the first port 11, and the valve 5 is in a closed state in which the discharge port 8 of the sleeve 4 is closed as shown in FIG. Maintained. When the fluid pressure in the supply flow path 10 becomes high, the contracted biasing member 6 is pushed back to the first port 11 side as shown in FIG. 4, and the valve 5 is separated from the inlet 7 of the sleeve 4. Thus, the discharge port 8 of the sleeve 4 is opened. Thus, the first port 11 and the second port 12 communicate with each other, and excess fluid (oil) returns to the suction port of the oil pump 20. That is, in this case, the valve opening pressure of the relief valve 1 is set to a high pressure (second valve opening pressure). In other words, when the OSV 15 (valve position changing mechanism 13) is not in operation, the fluid is discharged from the discharge port 8 by causing the fluid pressure of the fluid to act on the valve 5 to the second valve opening pressure or higher.

  Here, the valve opening pressure refers to a fluid pressure necessary for the inflow port 7 and the discharge port 8 to communicate with each other. Specifically, the fluid (oil) discharged from the oil pump 20 acts on the valve 5, and the valve 5 moves away from the sleeve 4 against the urging force of the urging member 6, thereby moving the inlet 7. And the fluid pressure required for the communication between the outlet 8 and the outlet 8. In addition, the low pressure setting (first valve opening pressure) allows the inlet 7 and the discharge port 8 to communicate with each other with a smaller fluid pressure than the high pressure setting (second valve opening pressure).

  As described above, when the relief valve 1 is operated, sound and vibration may be generated due to contact of each member. For example, when the OSV 15 is turned OFF in order to set a high pressure setting, the sleeve 4 is pushed back to the first port 11 side, and when the end surface 4b of the sleeve 4 moves to the sliding end point, the impact when contacting the plug 3 Causes sound and vibration. Further, when the valve 5 is in an open state in which the valve 5 is separated from the inlet 7 of the sleeve 4 and opens the discharge port 8 of the sleeve 4, the valve 5 is biased 6 when the fluid pressure in the supply flow path 10 decreases. The contact surface 4e of the sleeve 4 and the contact surface 5a of the valve 5 come into contact with each other, and sound and vibration are generated. Further, such sound and vibration may be continuously generated due to the pulsation of the fluid caused by the oil pump 20 even after the members once contact each other.

  In such a case, the relief valve 1 according to the present invention includes the elastic member 16 between the plug 3 and the plate member 2B of the valve body 2, so that sound and vibration are attenuated by the elastic member 16 and Transmission to the member can be suppressed. Further, since the seal ring 17 is provided between the outer peripheral surface of the plug 3 and the inner peripheral surface of the body main body 2A of the valve body 2, sound and vibration transmitted through this path are also attenuated by the seal ring 17. be able to. Further, when fluid flows from the second port 12 or the back pressure channel 14 between the outer peripheral surface of the plug 3 and the inner peripheral surface of the body main body 2A, between the bottom surface of the plug 3 and the plate member 2B. The plug 3 moves to the first port 11 side, the valve opening pressure of the relief valve 1 is different from the design value, and there may be a problem that appropriate relief is not performed. However, by providing the seal ring 17, it is possible to prevent the fluid from flowing between the bottom surface of the plug 3 and the plate member 2B, and to avoid the movement of the plug 3. Therefore, the above problem can be avoided. it can.

  FIG. 5 is a sectional view showing the shape of the elastic member 16 in an uncompressed state, and FIG. 6 is a cross-sectional view showing the shape of the elastic member 16 in a compressed state. The elastic member 16 is formed in an annular shape, and is assembled in a state of being fitted to a columnar protrusion 3 a provided at the center of the bottom surface of the plug 3. The height dimension of the protrusion part 3a is smaller than the thickness dimension of the elastic member 16, and it is comprised so that the plate member 2B of the valve body 2 and the protrusion part 3a may not contact. In the present embodiment, the dimensions and characteristics of the elastic member 16 are determined so that the plate member 2B and the protruding portion 3a do not come into contact with each other even when the elastic member 16 is compressed, thereby further improving the sound and vibration attenuation function. ing. When the elastic member 16 is compressed, a small gap is provided between the inner peripheral surface of the elastic member 16 and the protruding portion 3a so as not to prevent the deformation of the elastic member 16.

  According to the above configuration, the elastic member 16 can be easily positioned by the protruding portion 3a, and the elastic member 16 is uniformly arranged in the circumferential direction, so that the plug 3 can be prevented from being inclined. Furthermore, if the elastic member 16 is configured so that the entire region of the elastic member 16 does not protrude from the region sandwiched between the bottom surface of the plug 3 and the plate member 2B and is compressed and deformed within the region, the outer diameter, inner diameter, The spring constant can be defined only by the hardness and thickness of the member. Therefore, the elastic member 16 can be easily selected according to the performance of the relief valve 1.

  In addition, as other embodiment regarding the shape and arrangement | positioning of the elastic member 16, the shape etc. which were shown, for example in FIG.7 and FIG.8 may be sufficient. In FIG. 7, a recess 3b is formed on the bottom surface of the plug 3, and a disk-shaped elastic member 16 is disposed in the recess 3b. In FIG. 8, the elastic member 16 is easily positioned by fitting the protruding portion 16 a formed on the elastic member 16 into the hole 3 c formed on the bottom surface of the plug 3. The shape and arrangement of the elastic member 16 are not limited to those described above, and any other configuration may be used as long as sound and vibration transmitted from the plug 3 to the valve body 2 can be reduced.

  As shown in FIGS. 1 to 4, the relief valve 1 according to the present invention is connected to the valve body 2 on the outer peripheral surface of the sleeve 4 at both ends of the sleeve 4 (only in the vicinity of both ends). A sliding surface 4c is formed, and a portion (outer peripheral surface 4d) sandwiched between both end portions (both sliding surfaces 4c) does not slide with the valve body 2. Since the position of the sleeve 4 is changed using the fluid pressure of the first port 11, it is desirable that the sliding resistance with respect to the valve body 2 is as small as possible. Therefore, by distributing the sliding surface 4c with the valve body 2 to the vicinity of both ends of the sleeve 4, the area of the sliding surface during sliding is reduced, and the inclination of the sleeve 4 is kept to a minimum. The frictional force generated between the two and the four is reduced as much as possible. By the sliding surface 4c, the sleeve 4 inside the valve body 2 is not inclined with respect to the axial direction inside the valve body 2, and maintains the posture along the axial direction inside the valve body 2. As it is, it moves between the first port 11 and the second port 12.

[Other Embodiments]
(1) The relief valve 1 according to the present invention includes a first communication hole 4f that discharges the fluid or air inside the sleeve 4 from the side opposite to the first port 11 through the valve 5. Is preferably provided on the sleeve 4. When the first communication hole 4f is provided in the sleeve 4, for example, as shown in FIG. 9, the first communication hole 4f is provided on the outer peripheral surface of the sleeve 4 opposite to the first port 11 side. When the position of the sleeve 4 is changed by the valve position changing mechanism 13, the volume of the fluid or air inside the sleeve 4 that is opposite to the first port 11 side with respect to the valve 5 is separated from the valve 5. Increase or decrease. At that time, the fluid or air on the opposite side to the first port 11 side is discharged by the first communication hole 4f, so that the fluid can freely enter and exit, and the resistance when the sleeve 4 moves is reduced. Can do.

(2) In the relief valve 1 according to the present invention, as shown in FIG. 10, out of the fluid or air inside the sleeve 4, the fluid or air on the side opposite to the first port 11 side across the valve 5 is supplied. The valve 5 is preferably provided with a second communication hole 5b for discharging. When the valve 5 is pushed down by the fluid pressure from the first port 11, the fluid or air on the side opposite to the first port 11 across the valve 5 becomes a resistance. When the second communication hole 5b is provided in the valve 5, as shown in FIG. 10 (a), the fluid or air passes through the second communication hole 5b while the valve 5 is being pushed down by the fluid pressure from the first port 11. It will be discharged to the second port 12 through the discharge port 8 of the sleeve 4. Accordingly, the discharge of the fluid in the space is promoted through the discharge port 8 of the sleeve 4, and the operation of the valve 5 becomes smooth. As shown in FIG. 10B, when the valve 5 is in the open state in which the valve 5 is separated from the inflow port 7 of the sleeve 4 and opens the discharge port 8, the second communication hole 5b and the discharge port 8 do not communicate with each other.

  The relief valve according to the present invention is not limited to adjusting the hydraulic pressure of the engine lubrication system, and can be widely used for various hydraulic pressure adjustments.

DESCRIPTION OF SYMBOLS 1 Relief valve 2 Valve body 3 Plug 3a Protrusion part 4 Sleeve 4a End surface 4b End surface (end part)
4c Sliding surface 4d Outer peripheral surface 4f 1st communication hole 5 Valve 5b 2nd communication hole 6 Energizing member 7 Inlet 8 Outlet 11 First port 12 Second port 13 Valve position change mechanism 14 Back pressure channel (valve position) Change mechanism)
15 OSV (Valve position change mechanism)
16 Elastic member 17 Seal ring

Claims (11)

A valve body having a first port and a second port;
A sleeve housed in the valve body and having an inflow port communicating with the first port and a discharge port communicating with the second port;
The sleeve is accommodated and moves to the inlet side to prohibit communication between the inlet and the outlet, and moves to the opposite side of the inlet to connect the inlet and the outlet. A valve that allows communication;
A biasing member that biases the valve toward the inlet;
A valve position changing mechanism for changing a relative position between the valve body, the sleeve and the valve;
A plug that is supported and fixed to the valve body via an elastic member, and that contacts the end of the sleeve when the sleeve moves to a sliding end opposite to the inflow port;
Relief valve with   2. The relief valve according to claim 1, wherein a protrusion having a height smaller than the thickness of the elastic member is provided at the center of the bottom surface of the plug, and the annular elastic member is fitted to the protrusion.   3. The relief valve according to claim 2, wherein an outer edge of the elastic member is positioned inside an outer edge of a bottom surface of the plug when the elastic member is compressed and deformed.   The relief valve according to claim 1, wherein a seal ring is provided between an inner peripheral surface of the valve body and an outer peripheral surface of the plug.   5. The valve position changing mechanism according to claim 1, wherein the pressure of the fluid flowing through the first port is applied to the sleeve to move in the same direction as the urging direction of the urging member. The relief valve described.   2. The valve position changing mechanism includes an OSV that switches whether or not the fluid pressure of the fluid flowing through the first port is applied to the sleeve to move in the same direction as the urging direction of the urging member. The relief valve of any one of -5. When the valve position changing mechanism is activated, the fluid is discharged from the discharge port by causing the fluid pressure of the fluid to act on the valve at a first valve opening pressure or higher,
When the valve position changing mechanism is inoperative, the fluid is discharged from the discharge port by causing the fluid pressure of the fluid to act on the valve at a second valve opening pressure or higher,
The relief valve according to any one of claims 1 to 6, wherein the second valve opening pressure is a fluid pressure higher than the first valve opening pressure. Of the both end faces of the sleeve, one end face faces the first port, and the other end face faces the flow path of the valve position changing mechanism,
The relief valve according to any one of claims 1 to 7, wherein an area of the other end face is set larger than an area of the one end face.   The sliding surface with the said valve body is formed in the site | part of the both ends of the said sleeve among the outer peripheral surfaces of the said sleeve, The said sliding surface is not formed in the site | part pinched by the said both ends. The relief valve according to any one of the above.   10. A first communication hole is provided in the sleeve for discharging the fluid or air in the sleeve, which is on the opposite side of the first port across the valve. The relief valve according to any one of the above.   11. The second communication hole for discharging the fluid or the air inside the sleeve out of the fluid or the air on the opposite side of the first port through the valve is provided in the valve. The relief valve according to any one of the above.

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