JP2024008421A - Damping valve and damper - Google Patents

Abstract

To provide a damping valve which can inhibit increase of manufacturing costs without causing size increase even when enabling adjustment of damping force, and to provide a damper.SOLUTION: A damping valve V includes: a piston 5 having a valve seat 5d erected from an outer periphery of an opening end of a port 5b and enclosing the port 5b; an annular leaf valve 17 which is overlapped with the piston 5 and may be seated on or separated from a valve seat 5e; a facing member 12 which is disposed at the non-valve seat member side of the leaf valve 17, spaced apart from and facing the leaf valve 17; a biasing member 16 disposed between the leaf valve 17 and the facing member 12 and having a magnetic viscosity elastomer which biases the leaf valve 17 toward the valve seat 5e; and a coil 10 which causes a magnetic field to act on the biasing member 16.SELECTED DRAWING: Figure 2

Description

The present invention relates to damping valves and shock absorbers.

2. Description of the Related Art Some damping valves are used in shock absorbers used in vehicle suspensions, etc., and enable adjustment of the damping force generated by the shock absorbers. Such a damping valve includes, for example, a valve seat member having a port, a valve element that seats and separates from the valve seat member to open and close the port, a spring that biases the valve element toward the valve seat member, and a valve element. The valve is equipped with a solenoid that applies a thrust opposite to the biasing force of the spring, and by adjusting the amount of current supplied to the solenoid, the thrust applied to the valve body can be changed to change the valve opening pressure and degree of valve opening. let

A shock absorber using such a damping valve includes, for example, a cylinder, a piston that is inserted into the cylinder and divides the cylinder into a compression side chamber and a compression side chamber in which the cylinder is filled with hydraulic oil, and A piston rod connected to a piston, an outer cylinder that covers the cylinder, an intermediate cylinder arranged between the cylinder and the outer cylinder, a reservoir formed by an annular gap between the intermediate cylinder and the outer cylinder, and a cylinder. a damping passage that is formed in the gap between the cylinder and the intermediate cylinder and communicates the expansion side chamber with the reservoir; a rectification passage that is provided in the piston and allows only the flow of hydraulic oil from the compression side chamber to the expansion side chamber; The damping valve is provided in the middle of the damping passage of the shock absorber.

In the shock absorber configured as described above, when the hydraulic oil is expanded or contracted, the hydraulic oil is pushed out from inside the cylinder to the reservoir and passes through the damping valve. Therefore, by changing the valve opening pressure or the valve opening degree of the damping valve, It is possible to adjust the damping force during expansion and contraction.

Japanese Patent Application Publication No. 2022-55571

However, since the above-mentioned shock absorber is equipped with a damping valve equipped with a solenoid, the solenoid is installed with the solenoid protruding from the side of the outer cylinder, which increases the size of the shock absorber and increases the number of parts. This increases manufacturing costs.

Furthermore, as disclosed in Japanese Patent Application Laid-open No. 2021-027143, there is a shock absorber in which a damping valve equipped with a solenoid is installed in a piston part in a cylinder, but the piston part is elongated in the radial and axial directions. This makes it difficult to ensure the stroke length of the shock absorber, increases the outer diameter, and increases the number of parts, increasing manufacturing costs.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a damping valve and a shock absorber that can adjust the damping force without increasing the size of the valve and suppressing an increase in manufacturing costs.

To achieve the above object, the damping valve of the present invention includes a valve seat member having a port and a valve seat that rises from the outer periphery of the open end of the port and surrounds the port, and a valve seat member that is annular and overlaps the valve seat member. A leaf valve that can be placed on and off from a seat; a facing member that is disposed at a distance on the opposite side of the leaf valve and faces the leaf valve; and a leaf valve that is interposed between the leaf valve and the facing member. The valve includes a biasing member including a magnetorheological elastomer that biases the valve toward the valve seat, and a coil that applies a magnetic field to the biasing member.

The damping valve configured in this manner can adjust the damping force by employing a structure in which the leaf valve is biased with a biasing member having a magnetorheological elastomer whose elasticity can be changed by the action of a magnetic field. The parts required to adjust the damping force are the biasing member and the coil, so it is not only smaller than a large solenoid that has a fixed core, a movable core, and a spring in addition to the coil, but also has fewer parts. Because it requires less, the damping valve can be installed in the piston part or base valve part of the shock absorber.

Further, the damping valve includes a shaft member to which a valve seat member and a facing member are attached, and the leaf valve has an annular shape and is fixed between the valve seat member and the facing member with the shaft member on the inner peripheral side and the outer peripheral side is fixed between the valve seat member and the facing member. The biasing member may be provided between the outer peripheral side of the leaf valve and the opposing member.

According to the damping valve configured in this way, a coil is provided between the leaf valve and the valve stopper, unlike a general damping valve structure that includes a leaf valve and a valve stopper and cannot adjust the damping force. Since the damping force can be adjusted simply by interposing the biasing member, a damping force adjusting function can be easily and inexpensively provided to a damping valve that cannot adjust the damping force. Further, by fixing the leaf valve to the outer periphery of the shaft member, the direction in which the leaf valve is bent can be controlled, so that it becomes easier to cause the urging force of the urging member to match the direction in which the leaf valve is bent.

Furthermore, the damping valve is disposed between a shaft member to which the valve seat member and the opposing member are attached, and the leaf valve and the opposing member, and is movable in the axial direction with respect to the shaft member, The leaf valve may be provided with a valve suppressing member that contacts the member side, and the urging member may be interposed between the opposing member and the valve suppressing member to urge the leaf valve via the valve suppressing member. In addition, since the valve restraining member is movably provided on the outer periphery of the shaft member, the biasing force of the biasing member is applied to the leaf valve in the axial direction via the valve restraining member, effectively suppressing the deflection of the leaf valve. can.

According to the damping valve configured in this way, unlike the structure of the damping valve which has a spring between the leaf valve and the facing member and cannot adjust the damping force, a coil is provided to face the leaf valve instead of the spring. Since the damping force can be adjusted simply by interposing the biasing member between the damping force and the damping force, a damping force adjusting function can be easily and inexpensively provided to a damping valve that cannot adjust the damping force.

Further, the valve seat member and the opposing member in the damping valve may be formed of a soft magnetic material. According to the damping valve configured in this way, the valve seat member and the opposing member form a magnetic circuit, and the magnetic field generated by the coil is efficiently applied to the biasing member to obtain damping force with less electric power. Adjustment is possible.

Further, the shock absorber of the present invention includes a shock absorber body having an outer shell, a rod that is movably inserted in the outer shell in the axial direction, and two working chambers in which liquid is exchanged by moving the rod relative to the outer shell. and a damping valve provided between the working chambers. According to the shock absorber configured in this way, it is equipped with a damping valve that can be manufactured at low cost, so that costs can be reduced.

According to the valve and shock absorber of the present invention, even if the damping force can be adjusted, an increase in manufacturing cost can be suppressed without increasing the size.

FIG. 2 is a cross-sectional view of a shock absorber to which a damping valve is applied in one embodiment. FIG. 2 is an enlarged sectional view of a piston portion to which a damping valve according to an embodiment is applied. It is an enlarged sectional view of the piston part to which the damping valve of the 1st modification of one embodiment is applied. It is an enlarged sectional view of the piston part to which the damping valve of the 1st modification of one embodiment is applied.

Hereinafter, the valve and shock absorber of the present invention will be explained based on the drawings. The damping valve V in one embodiment is used as a damping valve for a piston portion of a shock absorber D, as shown in FIG.

Hereinafter, each part of the damping valve V and the shock absorber D will be explained in detail. The shock absorber D includes a shock absorber main body 1 including an outer shell 2 and a rod 3 that is movably inserted in the outer shell 2 in the axial direction, and two working chambers formed within the shock absorber main body 1. It includes a damping valve V provided between the expansion side chamber R1 and the compression side chamber R2.

The shock absorber main body 1 includes a cylinder 4, a piston 5 that is movably inserted into the cylinder 4 and partitions the inside of the cylinder 4 into a rebound chamber R1 and a compression side chamber R2, and a piston 5 that is inserted into the cylinder 4 and is inserted into the piston 5. It includes a rod 3 to be connected, and an outer shell 2 that covers a cylinder 4 and forms a reservoir chamber R between the cylinder 4 and the cylinder 4.

The cylinder 4 has a cylindrical shape, and the piston 5 is movably inserted therein as described above, and the expansion side chamber R1 is located above the piston 5 in FIG. 1, and the compression side chamber R2 is located below the piston 5 in FIG. are each separated. The expansion side chamber R1 and the compression side chamber R2 are filled with a liquid, specifically, hydraulic oil, for example. Note that as the liquid, in addition to hydraulic oil, water, an aqueous solution, etc. may be filled.

Further, the cylinder 4 is housed in a bottomed cylindrical outer shell 2 disposed on the outer circumferential side, and a reservoir chamber R is formed in an annular gap between the cylinder 4 and the outer shell 2. In this case, the inside of the reservoir chamber R is filled with hydraulic oil and gas, and when the liquid is used as the hydraulic oil, the gas is preferably an inert gas such as nitrogen to prevent deterioration of the hydraulic oil.

A valve case 6 is fitted to the lower end of the cylinder 4 in FIG. 1, and the pressure side chamber R2 and the reservoir chamber R are partitioned by the valve case 6. A rod guide 8 that slidably supports the rod 3 is fitted into the middle upper end. The rod guide 8 is fitted onto the inner periphery of the outer shell 2, and is fixed to the outer shell 2 by crimping the upper end of the outer shell 2 so as to be stacked above the rod guide 8 in FIG. When the rod guide 8 is fixed to the outer shell 2 in this way, the cylinder 4 is held between the valve case 6 placed on the bottom of the outer shell 2 and the rod guide 8, and the cylinder 4 is also inside the outer shell 2 together with the valve case 6. is fixed. Note that instead of crimping the upper opening end of the outer shell 2, a cap is screwed onto the upper opening, and the rod guide 8, cylinder 4, and valve case 6 are held between this cap and the bottom of the outer shell 2. Then, these members may be fixed within the outer shell 2.

The rod 3 is made of a soft magnetic material, and has a small diameter part 3a at the lower end in FIG. It includes a threaded portion 3c provided on the outer periphery of the lowermost end of the portion 3a, and a stepped portion 3d formed between the small diameter portion 3a and a portion above the small diameter portion 3a. Further, the rod 3 has a cylindrical shape, a small diameter portion 3a is closed at the lower end, and is provided with a hole 3e that communicates the inside of the rod 3 with the annular recess 3b.

A coil 10 is housed in an annular recess 3b formed in the small diameter portion 3a of the rod 3, and the coil 10 is connected to a power source (not shown) provided outside the shock absorber D through a cord 11 inserted into the rod 3. It is possible to supply current to.

On the outer periphery of the small diameter portion 3a of the rod 3, an annular valve stopper 12 made of a soft magnetic material, a cylindrical collar 13 made of a non-magnetic material, and an annular spacer 14 made of a non-magnetic material. A compression side leaf valve 15 as a leaf valve, a compression side biasing member 16 as a biasing member, a piston 5 as a valve seat member, a growth side leaf valve 17 as a leaf valve, and a growth side attachment as a biasing member. The biasing member 18, an annular spacer 19 made of a non-magnetic material, and an annular valve stopper 20 made of a soft magnetic material are fitted in this order. The valve stopper 12, the collar 13, the spacer 14, the compression side leaf valve 15, the piston 5, the expansion side leaf valve 17, the spacer 19, and the valve stopper 20 are connected to a piston screwed onto the threaded portion 3c of the small diameter portion 3a. It is held between the nut 21 and the stepped portion 3d of the rod 3 and fixed to the small diameter portion 3a. Further, the compression side biasing member 16 is interposed between the compression side leaf valve 15 and the valve stopper 12, and the growth side biasing member 18 is interposed between the growth side leaf valve 17 and the valve stopper 20. .

The valve stopper 12, which is disposed on the expansion side chamber side of the piston 5, is made of a soft magnetic material and has an annular shape, and is thicker on the inner circumference side than on the outer circumference side, as shown in FIG. 1, with the inner circumference side facing the piston. It has a convex portion 12a that protrudes downward. In addition, the valve stopper 20, which is disposed on the pressure side chamber side of the piston 5, is made of a soft magnetic material, has an annular shape, and is thicker on the inner circumference side than on the outer circumference side, so that the inner circumference side is on the piston side. It has a convex portion 20a that protrudes toward the middle upper side. The valve stopper 20 may be provided integrally with the piston nut 21.

The collar 13 is formed of a non-magnetic tube, is interposed between the valve stoppers 12 and 20, and is held between the stepped portion 3d of the rod 3 and the piston nut 21, and is attached to the rod together with the valve stoppers 12 and 20. It is immovably fixed to the outer periphery of 3.

The spacer 14 is annular and made of a non-magnetic material, and is fitted onto the outer periphery of the collar 13 and placed below the valve stopper 12 in FIG. The spacer 19 is annular and made of a non-magnetic material, and is fitted onto the outer periphery of the collar 13 and placed above the valve stopper 20 in FIG. Although the spacers 14 and 19 are composed of one annular plate, they may be composed of a plurality of annular plates.

The piston 5 is made of a soft magnetic material, has an annular shape, and, as shown in FIG. 2, serves as a valve seat member in the damping valve V and is attached to the outer periphery of the small diameter portion 3a of the rod 3 as a shaft member. It is fitted onto the outer periphery of the collar 13. A small diameter portion 3a fitted with a collar 13 is inserted into the inner periphery of the piston 5, and the small diameter portion 3a of the rod 3 protrudes downward from the lower end of the piston 5 in FIG. 1 to function as a shaft member. There is.

In this embodiment, the piston 5 as a valve seat member includes an annular piston body 5a and a plurality of extension ports that are arranged alternately on the same circumference of the piston body 5a and that penetrate the piston body 5a in the axial direction. 5b, a compression side port 5c, a petal-shaped extension side valve seat 5d that protrudes axially from the lower end of the piston body 5a in FIG. A petal-shaped pressure side valve seat 5e that protrudes and surrounds only the pressure side port 5c is provided. Further, a resin piston ring 22 is attached to the outer periphery of the piston 5 and is in sliding contact with the inner periphery of the cylinder 4. The piston 5 is movable in the vertical direction in FIG. 4 is divided into a growth side chamber R1 and a compression side chamber R2.

As described above, a plurality of the expansion side ports 5b and the compression side ports 5c are provided in the piston 5, and each of them is arranged on the same circumference with respect to the piston 5 around the center of the piston 5. Note that the number of expansion side ports 5b and compression side ports 5c installed is arbitrary and may be one.

Further, the expansion side valve seat 5d is a petal-shaped valve seat that avoids the outlet end of the compression side port 5c and surrounds only the outlet end of each expansion side port 5b without communicating with each other. , is a petal-shaped valve seat that surrounds only the outlet end of each pressure side port 5c without communicating with each other, avoiding the outlet end of the expansion side port 5b. The expansion side port 5b and the compression side port 5c are provided to be inclined with respect to the axial direction of the piston body 5a, and on the expansion side chamber R1 side of the piston body 5a, the compression side port 5c is larger than the expansion side port 5b. When the expansion side port 5b is opened toward the outer periphery side and the expansion side port 5b is opened toward the outer periphery side than the compression side port 5c on the pressure side chamber R2 side of the piston body 5a, both the expansion side valve seat 5d and the compression side valve seat 5e are annular valves. It may also be used as a seat.

The compression side leaf valve 15 is an annular plate formed of a non-magnetic material, and is fitted onto the outer periphery of the collar 13 and stacked so as to be seated on the compression side valve seat 5e on the expansion side chamber side of the piston 5 serving as a valve seat member. The inner periphery is clamped and fixed between the piston 5 and the spacer 14, and the outer periphery side is allowed to flex. In addition, when the outer periphery of the pressure side leaf valve 15 is seated on the pressure side valve seat 5e of the piston 5, the upper end in FIG. 1, which is the outlet end of the pressure side port 5c, is closed, and the outer periphery is bent upward in FIG. When separated from the valve seat 5e, the pressure side port 5c is opened. Although the pressure side leaf valve 15 is shown as being composed of a single annular plate, it may be composed of a plurality of annular plates, and in that case, the outer diameters of the annular plates may be different. .

As described above, since the spacer 14 is arranged on the upper side in FIG. 2, which is the side opposite to the valve seat member of the pressure side leaf valve 15, the valve stopper 12 as a facing member facing the pressure side leaf valve 15 is They are arranged at a distance equal to the height of the spacer 14 on the opposite side of the valve seat member of the pressure side leaf valve 15. When the pressure side leaf valve 15 is bent and comes into contact with the outer periphery of the pressure side leaf valve 15, the valve stopper 12 restricts further bending of the pressure side leaf valve 15 and suppresses plastic deformation of the pressure side leaf valve 15.

The expansion side leaf valve 17 is an annular plate formed of a non-magnetic material, and is fitted onto the outer periphery of the collar 13 so as to be seated on the expansion side valve seat 5d on the pressure side chamber side of the piston 5 serving as a valve seat member. The inner periphery is sandwiched and fixed between the piston 5 and the spacer 19, and the outer periphery side is allowed to flex. In addition, when the outer periphery of the growth-side leaf valve 17 is seated on the growth-side valve seat 5d of the piston 5, the lower end in FIG. 1, which is the outlet end of the growth-side port 5b, is closed, and the outer periphery is bent downward in FIG. When it is moved away from the growth side valve seat 5d, the growth side port 5b is opened. Although the extension side leaf valve 17 is shown as being composed of one annular plate, it may be composed of a plurality of annular plates, and in that case, even if the outer diameters of the annular plates are different, good.

As described above, the spacer 19 is disposed on the lower side in FIG. 20 are spaced apart from each other by the height of the spacer 19 on the side opposite to the valve seat member of the expansion side leaf valve 17. When the growth-side leaf valve 17 is bent and comes into contact with the outer periphery of the growth-side leaf valve 17, the valve stopper 20 restricts further deflection of the growth-side leaf valve 17 and prevents plastic deformation of the growth-side leaf valve 17. suppress.

The compression side biasing member 16 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The compression side biasing member 16 is fitted onto the outer periphery of the convex portion 12a of the valve stopper 12 and positioned in the radial direction, and has an axial length set to be greater than or equal to the axial length of the spacer 14. It is interposed between the stopper 12 and the pressure side leaf valve 15 in a compressed state. Therefore, the pressure-side urging member 16 always urges the pressure-side leaf valve 15 toward the piston 5 using the elastic force generated by itself.

The expansion side biasing member 18 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The expansion side biasing member 18 is fitted onto the outer periphery of the convex portion 20a of the valve stopper 20 and positioned in the radial direction, and has an axial length set to be greater than or equal to the axial length of the spacer 19. It is interposed between the valve stopper 20 and the expansion side leaf valve 17 in a compressed state. Therefore, the expansion-side urging member 18 always urges the expansion-side leaf valve 17 toward the piston 5 using the elastic force generated by itself.

Note that the compression side urging member 16 and the expansion side urging member 18 as urging members only need to be able to urge the corresponding compression side leaf valve 15 and expansion side leaf valve 17, respectively, using magnetorheological elastomer. The entire expansion side urging member 18 may be formed of magnetorheological elastomer, or the compression side urging member 16 and the expansion side urging member 18 partially urge the compression side leaf valve 15 and the expansion side leaf valve 17. It may also have a magnetorheological elastomer that can be used.

When the coil 10 attached to the outer periphery of the small diameter portion 3a of the rod 3 is energized, the small diameter portion 3a, the valve stopper 12, the piston 5, and the valve stopper 20 are made of soft magnetic material, and the spacers 14, 19 and the collar 13 are made of non-magnetic material. Since it is a magnetic material, the lines of magnetic force coming out of the coil 10 return to the coil 10 through the valve stopper 12, the compression side biasing member 16, the piston 5, the rebound side biasing member 18, and the valve stopper 20. The valve stopper 12, the piston 5, and the valve stopper 20 constitute a magnetic circuit, and when the coil 10 is energized, a magnetic field can be efficiently applied to the compression side biasing member 16 and the expansion side biasing member 18. Furthermore, by adjusting the amount of current applied to the coil 10, the strength of the magnetic field acting on the compression side urging member 16 and the expansion side urging member 18 can be adjusted. The elastic modulus of the expansion side biasing member 18 can be increased or decreased. When the elastic modulus of the compression-side biasing member 16 and the rebound-side biasing member 18 changes, the biasing force that the compression-side biasing member 16 applies to the compression-side leaf valve 15 and the biasing force that the rebound-side biasing member 18 applies to the growth-side leaf valve 17 change. and changes. Therefore, by adjusting the amount of current applied to the coil 10, the apparent bending rigidity of the compression side leaf valve 15 and the expansion side leaf valve 17 can be adjusted.

The damping valve V includes a piston 5 as a valve seat member including an expansion side port 5b, a compression side port 5c, an expansion side valve seat 5d surrounding the expansion side port 5b, and a compression side valve seat 5e surrounding the compression side port 5c; A growth-side leaf valve 17 that is stacked on the piston 5 and can be seated and removed from the growth-side valve seat 5d; a compression-side leaf valve 15 that is stacked on the piston 5 and that can be seated and taken off from the compression-side valve seat 5e; A valve stopper 20 as an opposing member that is arranged at a distance on the side opposite to the valve seat member and faces the expansion side leaf valve 17; and a valve stopper 20 as an opposing member that is arranged at a distance on the side opposite to the valve seat member of the compression side leaf valve 15 and is arranged at a distance on the side opposite to the valve seat member and is a compression side leaf. A valve stopper 12 as an opposing member facing the valve 15, and a magnetic viscosity valve interposed between the growth side leaf valve 17 and the valve stopper 20 to urge the growth side leaf valve 17 toward the growth side valve seat 5d. a biasing member 18 having an elastomer; and a biasing member 16 having a magnetorheological elastomer that is interposed between the pressure side leaf valve 15 and the valve stopper 12 and urges the pressure side leaf valve 15 toward the pressure side valve seat 5e. , a coil 10 that applies a magnetic field to the expansion side biasing member 18 and the compression side biasing member 16, and a small diameter portion 3a as a shaft member of the rod 3 rising from the axis of the piston 5.

Continuing, the valve case 6 is fitted to the lower end of the cylinder 4 to partition a pressure side chamber R2 inside the cylinder 4 and a reservoir chamber R formed between the cylinder 4 and the outer shell 2. The valve case 6 includes a pressure side damping passage 6a and a suction passage 6b that communicate the pressure side chamber R2 and the reservoir chamber R. Further, a pressure side valve 23 is provided at the reservoir chamber side end, which is the lower end of the valve case 6 in FIG. A check valve 24 is provided at the pressure side chamber side end of the valve case 6, which is the upper end in FIG. It is provided.

The buffer D is configured as described above, and the operation of the buffer D will be described below. First, when the rod 3 moves upward in FIG. 1 with respect to the cylinder 4 and the shock absorber D is extended, the piston 5 also moves upward with respect to the cylinder 4 together with the rod 3, and the expansion side chamber R1 is compressed. At the same time, the pressure side chamber R2 is expanded. As the growth side chamber R1 is compressed, the pressure in the growth side chamber R1 increases, and the growth side leaf valve 17 in the damping valve V is pressed by the pressure of the growth side chamber R1 acting through the growth side port 5b. When the force pushing downward in FIG. 2 due to the pressure in the growth side chamber R1 exceeds the urging force of the growth side urging member 18, the growth side leaf valve 17 bends and opens the growth side port 5b. Provides resistance to the flow of hydraulic fluid through. In this way, when the shock absorber D is extended, the growth side leaf valve 17 provides resistance to the flow of hydraulic oil, so the pressure in the growth side chamber R1 becomes higher than the pressure in the compression side chamber R2, and the shock absorber D is extended. Generates a damping force that suppresses operation. In addition, when the shock absorber D is extended, the pressure side leaf valve 15 is maintained in a state seated on the compression side valve seat 5e by the pressure of the expansion side chamber R1 and the biasing force of the compression side biasing member 16, so the compression side port 5c is blocked. Therefore, the hydraulic oil does not pass through the pressure side port 5c.

In the damping valve V of the present embodiment, the apparent bending rigidity of the extension side leaf valve 17 can be changed by adjusting the amount of current supplied to the coil 10, so that the damping force generated when the buffer D is extended is reduced. Can be adjusted in height.

Furthermore, when the shock absorber D is extended, the rod 3 withdraws from the cylinder 4, so there is a shortage of hydraulic fluid in the cylinder 4 corresponding to the volume of the rod 3 withdrawing. A check valve 24 provided in the reservoir chamber R is opened to supply water from the reservoir chamber R into the cylinder 4. The opening pressure of the check valve 24 is set very low to prevent the pressure inside the cylinder 4 from falling below atmospheric pressure.

Subsequently, when the rod 3 moves downward in FIG. 1 relative to the cylinder 4 and the shock absorber D is compressed, the piston 5 also moves downward relative to the cylinder 4 together with the rod 3, and the pressure side chamber R2 is compressed. At the same time, the expansion side chamber R1 is expanded. As the pressure side chamber R2 is compressed, the pressure inside the pressure side chamber R2 increases, and the pressure side leaf valve 15 in the damping valve V is pressed by the pressure of the pressure side chamber R2 acting through the pressure side port 5c. The pressure-side leaf valve 15 bends when the force pushing it upward in FIG. 2 due to the pressure of the pressure-side chamber R2 exceeds the urging force of the pressure-side urging member 16, opens the pressure-side port 5c, and causes the valve to pass through the pressure-side port 5c. Provides resistance to oil flow. Furthermore, when the shock absorber D is contracted, the amount of hydraulic oil that the rod 3 enters into the cylinder 4 becomes excessive. It moves to the reservoir room R via. In this way, when the shock absorber D is contracted, the pressure side leaf valve 15 and the pressure side valve 23 provide resistance to the flow of hydraulic oil, so the pressure in the pressure side chamber R2 becomes higher than the pressure in the expansion side chamber R1, and the shock absorber D generates a damping force that suppresses the extension operation. In addition, when the shock absorber D is in contraction operation, the growth side leaf valve 17 is maintained in a state seated on the growth side valve seat 5d by the pressure of the compression side chamber R2 and the urging force of the growth side urging member 18, so that the growth side leaf valve 17 is maintained seated on the growth side valve seat 5d. The port 5b is blocked and hydraulic oil does not pass through the expansion side port 5b.

In the damping valve V of this embodiment, the apparent bending rigidity of the compression side leaf valve 15 can be changed by adjusting the amount of current supplied to the coil 10, so that the damping force generated when the shock absorber D is retracted can be increased or decreased. Can be adjusted.

As described above, the damping valve V includes the expansion side port 5b and the compression side port 5c, the expansion side valve seat 5d that rises from the outer periphery of the opening end of the expansion side port 5b and the compression side port 5c, and surrounds the expansion side port 5b and the compression side port 5c, and the compression side valve. a piston (valve seat member) 5 having a seat 5e; a growth side leaf valve 17 which is annular and is stacked on the piston (valve seat member) 5 and can be seated and separated from the growth side valve seat 5d and the pressure side valve seat 5e; The compression side leaf valve 15, the expansion side leaf valve 17, and the valve stopper (opposing member) 12 that is arranged at a distance from the valve seat member side of the compression side leaf valve 15 and faces the expansion side leaf valve 17 and the compression side leaf valve 15. , 20 are interposed between the expansion side leaf valve 17 and the compression side leaf valve 15 and the valve stoppers (opposed members) 12 and 20 to connect the expansion side leaf valve 17 and the compression side leaf valve 15 to the expansion side valve seat 5d and the compression side. Equipped with a growth side biasing member 18 and a compression side biasing member 16 having a magnetorheological elastomer that biases toward the valve seat 5e, and a coil 10 that applies a magnetic field to the growth side biasing member 18 and the compression side biasing member 16. ing.

The damping valve V configured in this manner attaches the expansion side leaf valve 17 and the compression side leaf valve 15 with the expansion side urging member 18 and the compression side urging member 16, which have a magnetorheological elastomer whose elasticity can be changed by the action of a magnetic field. By adopting a damping structure, the damping force can be adjusted. The components necessary to adjust the damping force are the expansion side biasing member 18, the compression side biasing member 16, and the coil 10, so compared to a large solenoid that has a fixed core, a movable core, and a spring in addition to the coil. The damping valve V can be installed in the piston portion of the shock absorber D because the damping valve V is not only small in size but also requires a small number of parts. Therefore, according to the damping valve V of this embodiment, even if the damping force can be adjusted, it does not increase in size and can suppress an increase in manufacturing costs.

The expansion side biasing member 18 and the compression side biasing member 16 are both annular and have a plurality of column shapes arranged in the circumferential direction between the valve stoppers 12, 20 and the leaf valves 15, 17, or a plurality of columnar shapes provided in the circumferential direction. It may be made of an arc-shaped magnetorheological elastomer. In that case, each magnetorheological elastomer constituting the growth-side biasing member 18 is provided at a position facing the opening end of the growth-side port 5b with respect to the growth-side leaf valve 17 in the axial direction. The apparent bending rigidity can be efficiently adjusted, and each magnetorheological elastomer constituting the pressure side biasing member 16 is provided at a position facing the opening end of the pressure side port 5c with respect to the pressure side leaf valve 15 in the axial direction. The apparent bending rigidity of the pressure side leaf valve 15 can be efficiently adjusted. Note that the shape of the magnetorheological elastomer included in the expansion side biasing member 18 and the compression side biasing member 16 is such that the magnetorheological elastomer can bias the leaf valves 15 and 17, and the biasing force can be adjusted by the amount of current supplied to the coil 10. If possible, the design can be changed arbitrarily. Further, when the expansion side biasing member 18 is held by the valve stopper 20 as an opposing member, and when the compression side urging member 16 is held by the valve stopper 12 as an opposing member, the shapes of the valve stoppers 12 and 20 are The design can be changed as appropriate depending on the shapes of the expansion side biasing member 18 and the compression side biasing member 16. Therefore, for example, by providing holes in the valve stoppers 12 and 20 and fitting the compression side biasing member 16 and the expansion side biasing member 18 into the holes, the compression side biasing member 16 and the expansion side biasing member 18 are fitted to the valve stoppers 12 and 20. The side biasing member 18 may be held.

In addition, in the damping valve V of this embodiment, in order to make it possible to adjust both the damping force when the shock absorber D is extended and the damping force when it is contracted, the extension side leaf valve 17 and the valve stopper 20 are provided. and a growth-side urging member 18 interposed between the growth-side leaf valve 17 and the valve stopper 20, and a compression-side leaf valve 15, a valve stopper 12, a compression-side leaf valve 15, and a valve stopper 12. and a pressure side biasing member 16 interposed therebetween. If the damping force can be adjusted only when the shock absorber D is extended, the compression side biasing member 16 may be eliminated; if the damping force can be adjusted only when the shock absorber D is retracted, the compression side biasing member 16 may be eliminated. The biasing member 18 may be eliminated.

In addition, the damping valve V uses the valve case 6 as a valve seat member, stacks the leaf valve on the valve seat surrounding the compression side damping passage 6a of the valve case 6, and makes the opposing member face the leaf valve with an interval. A biasing member having a magnetorheological elastomer may be interposed between the valve and the opposing member, and a coil may be installed to apply a magnetic field to the biasing member.

The shock absorber D also includes an outer shell 2, a rod 3 inserted into the outer shell 2 so as to be movable in the axial direction, and an expansion side chamber (an operating chamber) in which hydraulic oil (liquid) moves back and forth as the rod 3 moves with respect to the outer shell 2. ) R1 and a compression side chamber (working chamber) R2, and a damping valve V provided between the expansion side chamber (working chamber) R1 and the pressure side chamber (working chamber) R2. According to the shock absorber D configured in this manner, since the damping valve V is provided at a low cost and small size, even if the damping force can be adjusted, an increase in manufacturing cost can be suppressed without causing an increase in size.

In this embodiment, the valve seat member is the piston 5, and the damping valve V is installed in the piston part of the shock absorber D. However, the valve case 6 of the shock absorber D is used as the valve seat member, and two working chambers are installed. Alternatively, a damping valve V may be installed between the pressure side chamber R2 and the reservoir chamber R. That is, the damping valve V may be installed in the base valve portion of the shock absorber D. In this way, the damping valve V is provided between the two working chambers formed in the shock absorber D, and thus can function as a damping force generation source in the shock absorber D, and can adjust the damping force.

The shock absorber D includes a cylinder 4 inside the outer shell 2, and a piston 5 divides the inside of the cylinder 4 into a compression side chamber R1 and a compression side chamber R2. It is said to be a double-tube type shock absorber equipped with a reservoir chamber R, but the cylinder 4 is eliminated and a single-tube type shock absorber is adopted in which a piston connected to a rod 3 is slidably inserted into the inner periphery of the outer shell 2. It may also be a buffer. Since the shock absorber D configured as a single cylinder in this way has two working chambers, the expansion side chamber and the pressure side chamber, the damping valve V may be provided in the piston portion of the shock absorber D. Moreover, although the installation location of the damping valve changes depending on the configuration of the shock absorber D, the damping valve V may be installed at an optimal location according to the configuration of the shock absorber D.

Furthermore, in the damping valve V of this embodiment, the piston (valve seat member) 5 and the valve stopper (opposed member) 12, 20, which are in a positional relationship that sandwich the biasing members 16, 18 in the axial direction, are made of soft magnetic material. Since the piston (valve seat member) 5 and the valve stopper (opposed member) 12, 20 constitute a magnetic circuit, the magnetic field generated by the coil 10 acts efficiently on the biasing members 16, 18. Therefore, it is possible to adjust the damping force with less electric power.

Furthermore, in the damping valve V of this embodiment, since the non-magnetic collar 13 is disposed between the piston 5 as a valve seat member and the small diameter portion 3a holding the coil 10, the lines of magnetic force of the coil 10 are The valve stoppers 12, 20 and the piston 5 can form a magnetic circuit for efficient passage. By providing the collar 13 in this way, the magnetic field can be applied more efficiently to the expansion side biasing member 18 and the compression side biasing member 16, but the collar 13 is abolished and the piston 5 is directly attached to the outer circumference of the small diameter portion 3a. They can also be fitted together. Further, the valve stoppers 12 and 20 may be fitted to the outer periphery of the collar 13 so that the piston nut 21 also constitutes a magnetic circuit. If the collar 13 is to be abolished, the inner and outer parts of the piston 5 are made up of separate parts, with the inner part made of a non-magnetic material and the outer part made of a soft magnetic material. It may also be formed in the body. As the soft magnetic material, for example, iron or iron powder molded by sintering is used. In this way, the lines of magnetic force of the coil 10 pass through the outer periphery of the piston 5, so that a magnetic field can be efficiently applied to the expansion side biasing member 18 and the compression side biasing member 16. Further, the outer peripheral side portion of the piston 5, the expansion side biasing member 18, and the compression side biasing member 16 may be arranged at a position where they overlap in the axial direction of the rod 3. In this way, the direction of the magnetic field generated in the coil 10 and passing through the magnetorheological elastomer in the expansion side biasing member 18 and the compression side biasing member 16 is adjusted. The deviation from the direction of the line of action of the load received from the leaf valves 15, 17 can be reduced, and the adjustment range of the urging force applied to the leaf valves 15, 17 by the expansion side urging member 18 and the compression side urging member 16 can be widened.
Note that since the coil 10 is installed at the outer periphery of the small diameter portion 3a as a shaft member, the coil 10 can be energized by the wiring placed inside the rod 3, and the coil 10 can be installed easily. The coil 10 may be installed at a location other than the outer periphery of the small diameter portion 3a, and may be held by a valve seat member, for example.

Further, the damping valve V of the present embodiment includes a small diameter portion (shaft member) 3a to which a piston (valve seat member) 5 and a valve stopper (opposed member) 12, 20 are attached, and an expansion side leaf valve (leaf valve). ) 17 and a pressure side leaf valve (leaf valve) 15 are fixed between a piston (valve seat member) 5 that is annular and has a small diameter portion (shaft member) 3a on the inner peripheral side and valve stoppers (opposing members) 12 and 20. is allowed to deflect on the outer circumferential side, and the biasing members 16 and 18 are connected to the outer circumferential sides of the expansion side leaf valve (leaf valve) 17 and the compression side leaf valve (leaf valve) 15 and the valve stoppers (opposing members) 12 and 20. is provided in between. According to the damping valve V configured in this way, unlike a general damping valve structure that includes a leaf valve and a valve stopper and cannot adjust the damping force, the coil 10 is provided and the leaf valve 15 (17) Since the damping force can be adjusted simply by interposing the biasing member 16 (18) between the valve stopper 12 (20), a damping force adjustment function can be provided inexpensively and easily to a damping valve whose damping force cannot be adjusted. can. In addition, by fixing the leaf valve 15 (17) to the outer periphery of the small diameter portion (shaft member) 3a, the direction in which the leaf valve 15 (17) bends can be controlled, so that the urging force of the urging member 16 (18) can be controlled by the leaf valve 15 (17). It becomes easier to operate the valve 15 (18) in the same direction as the valve 15 (18) is bent.

Further, the damping valve V1 may be configured like the first modification example of the damping valve V1 of the embodiment shown in FIG. The configuration of the damping valve V1 in the first modification will be described below, but since the same members as those in the damping valve V of one embodiment will be described repeatedly, the same reference numerals will be given and detailed description will be omitted. The damping valve V1 of the first modification is provided in the piston portion of the shock absorber D, and the other structure of the shock absorber D is the same as the above-mentioned structure.

The damping valve V1 of the first modification of the embodiment includes a piston 5 as a valve seat member, a growth side leaf valve 17 that can be seated on and taken off from a growth side valve seat 5d on the piston 5 and a compression side valve seat 5e, and a compression side leaf. The valve 15 , opposing members 30 and 31 that are arranged at intervals on the side opposite to the valve seat member of the expansion leaf valve 17 and the compression side leaf valve 15 and face the expansion leaf valve 17 and the compression side leaf valve 15 , and the coil 10 and a small diameter portion 3a as a shaft member in the rod 3 rising from the piston 5, and a small diameter portion 3a which is disposed between the expansion side leaf valve 17 and the opposing member 30 and is movable in the axial direction on the outer periphery of the expansion side leaf valve 17. A valve suppressing member 32 that comes into contact with the side of the leaf valve 17 opposite to the valve seat member, and a pressure side leaf valve that is disposed between the pressure side leaf valve 15 and the opposing member 31 and is movable in the axial direction on the outer periphery of the small diameter portion 3a. a valve suppressing member 33 that abuts on the side opposite to the valve seat member 15; an expansion side biasing member 34 interposed between the opposing member 30 and the valve suppressing member 32; It is configured to include a growth side biasing member 34 interposed therebetween.

The damping valve V1 is provided in the piston portion of the shock absorber D like the damping valve V, and is assembled to the small diameter portion 3a as a shaft member of the rod 3. On the outer periphery of the small diameter portion 3a of the rod 3, an annular opposing member 31 made of a soft magnetic material, a cylindrical collar 36 made of a non-magnetic material, and a cylindrical spacer 37 made of a non-magnetic material are provided. , a pressure side leaf valve 15 as a leaf valve, a pressure side biasing member 35 as a biasing member, a valve suppressing member 32, a piston 5 as a valve seat member, a growth side leaf valve 17 as a leaf valve, and a valve. The restraining member 33, the expansion side biasing member 34 as a biasing member, and the cylindrical spacer 38 formed of a non-magnetic material are fitted in order. And, the opposing member 31, the collar 36, the spacer 37, the compression side leaf valve 15, the compression side biasing member 35, the valve suppressing member 32, the piston 5, the expansion side leaf valve 17, the valve suppressing member 33, the expansion side biasing member 34, The spacer 38 is fixed to the small diameter portion 3a by being sandwiched between the opposing member 30, which is made of a soft magnetic material and is screwed onto the threaded portion 3c of the small diameter portion 3a, and the stepped portion 3d of the rod 3. In this way, the growth side biasing member 34 is interposed between the opposing member 30 and the valve suppressing member 32 and urges the growth side leaf valve 17, and the compression side biasing member 35 is interposed between the opposing member 31 and the valve suppressing member 32. It is interposed between the holding member 33 and the holding member 33 .

The opposing member 31, which is disposed on the expansion side chamber side of the piston 5, is formed of a soft magnetic material and has an annular shape, and is thicker on the inner circumferential side than on the outer circumferential side, and the inner circumferential side is on the piston side as shown in FIG. It has a convex portion 31a that protrudes downward. The opposing member 30, which is disposed closer to the pressure chamber than the piston 5, is made of a soft magnetic material, has an annular shape, has a threaded groove on its inner periphery so that it can function as a piston nut, and has a threaded groove on its outer periphery. It includes a flange 30a and a convex portion 30b projecting upward in FIG. 3. The opposing member 30 may be fixed to the small diameter portion 3a separately from the piston nut.

The collar 36 is formed of a non-magnetic tube, is interposed between the opposing members 30 and 31, and is held between the stepped portion 3d of the rod 3 and the opposing member 30, and is attached to the rod together with the opposing members 30 and 31. It is immovably fixed to the outer periphery of 3.

The spacer 37 has a cylindrical shape and is made of a non-magnetic material, and is fitted onto the outer periphery of the collar 36 and placed below the opposing member 31 in FIG. The spacer 38 is annular and made of a non-magnetic material, and is fitted onto the outer periphery of the collar 36 and placed above the opposing member 30 in FIG. 3 .

The compression side leaf valve 15, the piston 5, and the expansion side leaf valve 17 are stacked in order and fitted onto the outer periphery of the collar 36, and their inner peripheries are sandwiched and fixed by spacers 37 and 38. The pressure-side leaf valve 15 has an inner peripheral side fixed and an outer peripheral side allowed to flex, and opens and closes the pressure-side port 5c by seating on and leaving the pressure-side valve seat 5e. The growth-side leaf valve 17 has an inner circumferential side fixed and an outer circumferential side allowed to flex, and opens and closes the growth-side port 5b by sitting on and leaving the growth-side valve seat 5d.

At the upper side of the pressure side leaf valve 15 in FIG. It is fitted to the outer periphery so that it can move up and down. Since the valve suppressing member 33 is in sliding contact with the outer periphery of the collar 36, it can move in the axial direction without axial wobbling with respect to the small diameter portion 3a as a shaft member into which the collar 36 is fitted.

At the lower part of FIG. 3, which is the side opposite to the valve seat member of the expansion side leaf valve 17, there is a valve suppressing member 32 which is cylindrical and has a flange on its outer periphery that comes into contact with the side surface opposite to the valve seat of the expansion side leaf valve 17. It is fitted to the outer periphery of 36 so that it can move up and down. Since the valve suppressing member 32 is in sliding contact with the outer periphery of the collar 36, it can move in the axial direction without axial wobbling with respect to the small diameter portion 3a as a shaft member into which the collar 36 is fitted.

The compression side biasing member 35 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The compression side biasing member 35 is fitted to the outer periphery of the convex portion 31a of the opposing member 31 and positioned in the radial direction, and has an axial length set to be greater than or equal to the axial length of the spacer 37. It is interposed between the member 31 and the valve suppressing member 33 in a compressed state. Therefore, the pressure-side urging member 35 always urges the pressure-side leaf valve 15 toward the piston 5 via the valve suppressing member 33 with the elastic force generated by itself.

The expansion side biasing member 34 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The expansion side biasing member 34 is fitted to the outer periphery of the convex portion 30b of the opposing member 30 and positioned in the radial direction, and has an axial length set to be greater than or equal to the axial length of the spacer 38, It is interposed between the opposing member 30 and the valve suppressing member 32 in a compressed state. Therefore, the growth-side urging member 34 always urges the growth-side leaf valve 17 toward the piston 5 via the valve suppressing member 32 with the elastic force generated by itself.

Note that the compression side urging member 35 and the expansion side urging member 34 as urging members only need to be able to urge the corresponding compression side leaf valve 15 and expansion side leaf valve 17, respectively, with magnetorheological elastomer, so the entire body is made of magnetorheological elastomer. Alternatively, a part thereof may include a magnetorheological elastomer that can bias the compression side leaf valve 15 and the expansion side leaf valve 17.

When the coil 10 attached to the outer periphery of the small diameter portion 3a of the rod 3 is energized, the small diameter portion 3a, the opposing member 31, the piston 5, and the opposing member 30 are made of soft magnetic material, and the spacers 37, 38 and the collar 36 are made of non-magnetic material. Since it is a magnetic material, the lines of magnetic force coming out of the coil 10 return to the coil 10 through the opposing member 31, the compression side biasing member 35, the piston 5, the expansion side biasing member 34, and the opposing member 30. The opposing member 31, the piston 5, and the opposing member 30 constitute a magnetic circuit, and when the coil 10 is energized, a magnetic field can be efficiently applied to the compression side biasing member 35 and the expansion side biasing member 34. Furthermore, by adjusting the amount of current applied to the coil 10, the strength of the magnetic field acting on the compression side urging member 35 and the expansion side urging member 34 can be adjusted. The elastic modulus of the expansion side biasing member 34 can be increased or decreased. When the elastic modulus of the compression-side biasing member 35 and the rebound-side biasing member 34 change, the biasing force that the compression-side biasing member 35 applies to the compression-side leaf valve 15 and the biasing force that the rebound-side biasing member 34 applies to the growth-side leaf valve 17 change. and changes. Therefore, by adjusting the amount of current applied to the coil 10, the opening pressures of the compression side leaf valve 15 and the expansion side leaf valve 17 can be adjusted.

Next, the operation of the shock absorber D including the damping valve V1 of the first modification will be explained. First, when the rod 3 moves upward in FIG. 3 with respect to the cylinder 4 and the shock absorber D is extended, the piston 5 also moves upward with the rod 3 relative to the cylinder 4, and the expansion side chamber R1 is compressed. At the same time, the pressure side chamber R2 is expanded. As the growth side chamber R1 is compressed, the pressure in the growth side chamber R1 increases, and the growth side leaf valve 17 in the damping valve V1 is pressed by the pressure of the growth side chamber R1 acting through the growth side port 5b. When the force pushing downward in FIG. 3 due to the pressure of the growth side chamber R1 exceeds the urging force of the growth side urging member 34, the growth side leaf valve 17 bends and opens the growth side port 5b. Provides resistance to the flow of hydraulic fluid through. In this way, when the shock absorber D is extended, the growth side leaf valve 17 provides resistance to the flow of hydraulic oil, so the pressure in the growth side chamber R1 becomes higher than the pressure in the compression side chamber R2, and the shock absorber D is extended. Generates a damping force that suppresses operation. Note that when the shock absorber D is extended, the pressure side leaf valve 15 is maintained in a state seated on the compression side valve seat 5e by the pressure of the expansion side chamber R1 and the urging force of the compression side urging member 35, so the pressure side port 5c is blocked. Therefore, the hydraulic oil does not pass through the pressure side port 5c.

In the damping valve V1 of the present embodiment, the opening pressure of the extension side leaf valve 17 can be changed by adjusting the amount of current supplied to the coil 10, so the damping force generated when the buffer D is extended is adjusted in level. It is possible.

Furthermore, when the shock absorber D is extended, the rod 3 withdraws from the cylinder 4, so there is a shortage of hydraulic fluid in the cylinder 4 corresponding to the volume of the rod 3 withdrawing. A check valve 24 provided in the reservoir chamber R is opened to supply water from the reservoir chamber R into the cylinder 4. The opening pressure of the check valve 24 is set very low to prevent the pressure inside the cylinder 4 from falling below atmospheric pressure.

Next, when the rod 3 moves downward in FIG. 3 with respect to the cylinder 4 and the shock absorber D is compressed, the piston 5 also moves downward with respect to the cylinder 4 together with the rod 3, and the pressure side chamber R2 is compressed. At the same time, the expansion side chamber R1 is expanded. As the pressure side chamber R2 is compressed, the pressure inside the pressure side chamber R2 increases, and the pressure side leaf valve 15 in the damping valve V1 is pressed by the pressure of the pressure side chamber R2 acting through the pressure side port 5c. The pressure-side leaf valve 15 bends when the force pushing it upward in FIG. 3 due to the pressure in the pressure-side chamber R2 exceeds the urging force of the pressure-side urging member 35, opens the pressure-side port 5c, and causes the valve to pass through the pressure-side port 5c. Provides resistance to oil flow. Furthermore, when the shock absorber D is contracted, the amount of hydraulic oil that the rod 3 enters into the cylinder 4 becomes excessive. It moves to the reservoir room R via. In this way, when the shock absorber D is contracted, the pressure side leaf valve 15 and the pressure side valve 23 provide resistance to the flow of hydraulic oil, so the pressure in the pressure side chamber R2 becomes higher than the pressure in the expansion side chamber R1, and the shock absorber D generates a damping force that suppresses the extension operation. Note that when the shock absorber D is retracted, the growth side leaf valve 17 is maintained in a state seated on the growth side valve seat 5d by the pressure of the pressure side chamber R2 and the urging force of the growth side urging member 34, so that the growth side leaf valve 17 is maintained seated on the growth side valve seat 5d. The port 5b is blocked and hydraulic oil does not pass through the expansion side port 5b.

In the damping valve V1 of the present embodiment, the opening pressure of the pressure-side leaf valve 15 can be changed by adjusting the amount of current supplied to the coil 10, so the damping force generated when the buffer D is retracted can be adjusted. obtain.

As described above, the damping valve V1 includes the expansion side port 5b and the compression side port 5c, the expansion side valve seat 5d that rises from the outer periphery of the opening end of the expansion side port 5b and the compression side port 5c, and surrounds the expansion side port 5b and the compression side port 5c, and the compression side valve. a piston (valve seat member) 5 having a seat 5e; a growth side leaf valve 17 which is annular and is stacked on the piston (valve seat member) 5 and can be seated and separated from the growth side valve seat 5d and the pressure side valve seat 5e; a compression side leaf valve 15, an expansion side leaf valve 17 and opposing members 30, 31 that are arranged at intervals on the side opposite to the valve seat member of the compression side leaf valve 15 and face the expansion side leaf valve 17 and the compression side leaf valve 15; The coil 10, the small diameter part (shaft member) 3a to which the piston 5 and valve suppressing members 32, 33 are attached, and the extension side leaf valve 17 and the opposing member 30 are arranged between the small diameter part 3a and the small diameter part 3a in the axial direction on the outer periphery. A valve suppressing member 32 that is movable and comes into contact with the opposite valve seat member side of the expansion side leaf valve 17, and a valve suppressing member 32 that is disposed between the compression side leaf valve 15 and the opposing member 31 and moves axially toward the outer periphery of the small diameter portion 3a. A valve suppressing member 33 that is possible and comes into contact with the side of the compression side leaf valve 15 opposite to the valve seat member, and a growth side that is interposed between the opposing member 30 and the valve suppressing member 32 and urges the growth side leaf valve 17. It includes a biasing member 34 and a growth-side biasing member 34 that is interposed between the opposing member 31 and the valve suppressing member 33 and biases the pressure-side leaf valve 15 .

The damping valve V1 configured in this manner attaches the expansion side leaf valve 17 and the compression side leaf valve 15 with the expansion side urging member 34 and the compression side urging member 35, which have a magnetorheological elastomer whose elasticity can be changed by the action of a magnetic field. By adopting a damping structure, the damping force can be adjusted. The components necessary for adjusting the damping force are the expansion side biasing member 34, the compression side biasing member 35, and the coil 10, so compared to a large solenoid that has a fixed iron core, a movable iron core, and a spring in addition to the coil. The damping valve V1 can be installed in the piston portion of the shock absorber D because the damping valve V1 is not only small in size but also requires a small number of parts. Therefore, according to the damping valve V1 of the present embodiment, even if the damping force can be adjusted, an increase in manufacturing cost can be suppressed without causing an increase in size.

Further, according to the damping valve V1 of the present embodiment, the coil 10 is provided in place of the spring for the damping valve structure in which a spring is provided between the leaf valve and the opposing member and the damping force cannot be adjusted. Since the damping force can be adjusted simply by interposing the biasing member 35 (34) between the valve 15 (17) and the opposing member 31 (30), it is possible to adjust the damping force inexpensively and easily for a damping valve whose damping force cannot be adjusted. A damping force adjustment function can be added. Furthermore, since the valve suppressing member 32 (33) is movably provided on the outer periphery of the small diameter portion (shaft member) 3a, the urging force of the urging member 35 (34) is applied to the leaf via the valve suppressing member 32 (33). By acting on the valve 17 (15) in the axial direction, the deflection of the leaf valve 17 (15) can be efficiently suppressed.

Further, the damping valve V2 of the second modification of the embodiment shown in FIG. 4 may be configured. Hereinafter, the configuration of the damping valve V2 in the second modification will be described, but since the same members as the damping valves V and V2 described above will be explained repeatedly, the same reference numerals will be given and detailed explanation will be omitted. The damping valve V2 of the second modification is provided in the piston portion of the shock absorber D, and the other structure of the shock absorber D is the same as the above-mentioned structure.

The damping valve V2 of the second modification of the embodiment includes a piston 5 as a valve seat member, a growth side leaf valve 17 that can be seated on and taken off from a growth side valve seat 5d on the piston 5 and a compression side valve seat 5e, and a compression side leaf. The valve 15 , opposing members 30 and 31 that are arranged at intervals on the side opposite to the valve seat member of the expansion leaf valve 17 and the compression side leaf valve 15 and face the expansion leaf valve 17 and the compression side leaf valve 15 , and the coil 10 and a small diameter portion 3a as a shaft member in the rod 3 rising from the piston 5, and a small diameter portion 3a which is disposed between the expansion side leaf valve 17 and the opposing member 30 and is movable in the axial direction on the outer periphery of the expansion side leaf valve 17. A valve suppressing member 32 that comes into contact with the side of the leaf valve 17 opposite to the valve seat member, and a pressure side leaf valve that is disposed between the pressure side leaf valve 15 and the opposing member 31 and is movable in the axial direction on the outer periphery of the small diameter portion 3a. a valve suppressing member 33 that abuts on the side opposite to the valve seat member 15; an expansion side biasing member 34 interposed between the opposing member 30 and the valve suppressing member 32; It is configured to include a growth side biasing member 34 interposed therebetween.

The damping valve V2 is provided in the piston portion of the shock absorber D like the damping valves V and V1, and is assembled to the small diameter portion 3a as a shaft member of the rod 3. On the outer periphery of the small diameter portion 3a of the rod 3, an annular opposing member 31 made of a soft magnetic material, a cylindrical collar 36 made of a non-magnetic material, and a cylindrical guide tube 40 made of a non-magnetic material are provided. , a pressure side leaf valve 15 as a leaf valve, a pressure side biasing member 35 as a biasing member, a valve suppressing member 32, a piston 5 as a valve seat member, a growth side leaf valve 17 as a leaf valve, and a valve. The suppressing member 33, the expansion side biasing member 34 as a biasing member, and the cylindrical guide tube 41 formed of a non-magnetic material are fitted in order. And, the opposing member 31, the collar 36, the guide tube 40, the compression side leaf valve 15, the compression side biasing member 35, the valve suppressing member 32, the piston 5, the expansion side leaf valve 17, the valve suppressing member 33, the expansion side biasing member 34, The guide cylinder 41 is fixed to the small diameter portion 3a by being held between the opposing member 30, which is made of a soft magnetic material and screwed onto the threaded portion 3c of the small diameter portion 3a, and the step portion 3d of the rod 3. In this way, the growth side biasing member 34 is interposed between the opposing member 30 and the valve suppressing member 32 and urges the growth side leaf valve 17, and the compression side biasing member 35 is interposed between the opposing member 31 and the valve suppressing member 32. It is interposed between the holding member 33 and the holding member 33 .

The collar 36 is formed of a non-magnetic tube, is interposed between the opposing members 30 and 31, and is held between the stepped portion 3d of the rod 3 and the opposing member 30, and is attached to the rod together with the opposing members 30 and 31. It is immovably fixed to the outer periphery of 3.

The guide cylinder 40 has a cylindrical shape and is made of a non-magnetic material, and is fitted onto the outer periphery of the collar 36 and stacked below the opposing member 31 in FIG. The guide tube 41 is annular and made of a non-magnetic material, and is fitted onto the outer periphery of the collar 36 and placed above the opposing member 30 in FIG. 3 .

The piston 5 is fitted onto the outer periphery of the collar 36, and the inner periphery thereof is held and fixed between the guide tubes 40, 41. The pressure side leaf valve 15 is fitted onto the outer periphery of the guide cylinder 40 so as to be movable in the axial direction, and can be moved toward and away from the piston 5 as a whole, and is seated on and off the pressure side valve seat 5e to open the pressure side port 5c. Open and close. The expansion-side leaf valve 17 is fitted onto the outer periphery of the guide tube 41 so as to be movable in the axial direction, and can be moved as a whole toward and away from the piston 5, and can be seated on and off the expansion-side valve seat 5d for expansion. Open and close the side port 5b.

At the upper side of the pressure side leaf valve 15 in FIG. It is fitted to the outer periphery so that it can move up and down. Since the valve suppressing member 33 is in sliding contact with the outer periphery of the collar 36, it can move in the axial direction without axial wobbling with respect to the small diameter portion 3a as a shaft member into which the collar 36 is fitted.

At the lower part of FIG. 3, which is the side opposite to the valve seat member of the expansion side leaf valve 17, there is a valve suppressing member 32 which is cylindrical and has a flange on its outer periphery that comes into contact with the side surface opposite to the valve seat of the expansion side leaf valve 17. It is fitted to the outer periphery of 36 so that it can move up and down. Since the valve suppressing member 32 is in sliding contact with the outer periphery of the collar 36, it can move in the axial direction without axial wobbling with respect to the small diameter portion 3a as a shaft member into which the collar 36 is fitted.

The compression side biasing member 35 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The compression side biasing member 35 is fitted to the outer periphery of the convex portion 31a of the opposing member 31 and positioned in the radial direction, and has an axial length set to be greater than or equal to the axial length of the guide tube 40. It is interposed between the member 31 and the valve suppressing member 33 in a compressed state. Therefore, the pressure-side urging member 35 always urges the pressure-side leaf valve 15 toward the piston 5 via the valve suppressing member 33 with the elastic force generated by itself. When the force in the direction of separating the pressure side leaf valve 15 from the piston 5 due to the pressure in the pressure side chamber R2 exceeds the urging force of the pressure side urging member 35, the pressure side leaf valve 15 moves upward in FIG. to open the pressure side port 5c.

The expansion side biasing member 34 is annular and made of magnetorheological elastomer, and has elasticity, and when a magnetic field acts on it, the elastic modulus changes depending on the magnitude of the applied magnetic field. The expansion side biasing member 34 is fitted onto the outer periphery of the convex portion 30b of the opposing member 30 and positioned in the radial direction, and has an axial length set to be equal to or longer than the axial length of the guide tube 41, It is interposed between the opposing member 30 and the valve suppressing member 32 in a compressed state. Therefore, the growth-side urging member 34 always urges the growth-side leaf valve 17 toward the piston 5 via the valve suppressing member 32 with the elastic force generated by itself. When the force in the direction of separating the growth-side leaf valve 17 from the piston 5 due to the pressure in the growth-side chamber R1 exceeds the biasing force of the growth-side biasing member 34, the growth-side leaf valve 17 moves downward in FIG. The extension side port 5b is opened by separating them.

Note that the compression side urging member 35 and the expansion side urging member 34 as urging members only need to be able to urge the corresponding compression side leaf valve 15 and expansion side leaf valve 17, respectively, using magnetorheological elastomer. The entire expansion side urging member 34 may be formed of magnetorheological elastomer, or the compression side urging member 35 and the expansion side urging member 34 partially urge the compression side leaf valve 15 and the expansion side leaf valve 17. It may also have a magnetorheological elastomer that can be used.

Then, when the coil 10 attached to the outer periphery of the small diameter portion 3a of the rod 3 is energized, the small diameter portion 3a, the opposing member 31, the piston 5, and the opposing member 30 are made of soft magnetic material, and the guide tubes 40, 41 and the collar 36 are made of non-magnetic material. Since it is a magnetic material, the lines of magnetic force coming out of the coil 10 return to the coil 10 through the opposing member 31, the compression side biasing member 35, the piston 5, the expansion side biasing member 34, and the opposing member 30. The opposing member 31, the piston 5, and the opposing member 30 constitute a magnetic circuit, and when the coil 10 is energized, a magnetic field can be efficiently applied to the compression side biasing member 35 and the expansion side biasing member 34. Furthermore, by adjusting the amount of current applied to the coil 10, the strength of the magnetic field acting on the compression side urging member 35 and the expansion side urging member 34 can be adjusted. The elastic modulus of the expansion side biasing member 34 can be increased or decreased. When the elastic modulus of the compression-side biasing member 35 and the rebound-side biasing member 34 change, the biasing force that the compression-side biasing member 35 applies to the compression-side leaf valve 15 and the biasing force that the rebound-side biasing member 34 applies to the growth-side leaf valve 17 change. and changes. Therefore, by adjusting the amount of current applied to the coil 10, the opening pressures of the compression side leaf valve 15 and the expansion side leaf valve 17 can be adjusted.

Next, the operation of the shock absorber D provided with the damping valve V2 of the second modified example will be explained. First, when the rod 3 moves upward in FIG. 3 with respect to the cylinder 4 and the shock absorber D is extended, the piston 5 also moves upward with the rod 3 relative to the cylinder 4, and the expansion side chamber R1 is compressed. At the same time, the pressure side chamber R2 is expanded. As the growth side chamber R1 is compressed, the pressure in the growth side chamber R1 increases, and the growth side leaf valve 17 in the damping valve V2 is pressed by the pressure of the growth side chamber R1 acting through the growth side port 5b. When the force of pushing downward in FIG. 3 due to the pressure of the growth side chamber R1 exceeds the urging force of the growth side urging member 34, the growth side leaf valve 17 bends and opens the growth side port 5b. Provides resistance to the flow of hydraulic fluid through. In this way, when the shock absorber D is extended, the growth side leaf valve 17 provides resistance to the flow of hydraulic oil, so the pressure in the growth side chamber R1 becomes higher than the pressure in the pressure side chamber R2, and the shock absorber D is extended. Generates a damping force that suppresses operation. Note that when the shock absorber D is extended, the pressure side leaf valve 15 is maintained in a state seated on the compression side valve seat 5e by the pressure of the expansion side chamber R1 and the biasing force of the compression side biasing member 35, so the compression side port 5c is blocked. Therefore, the hydraulic oil does not pass through the pressure side port 5c.

In the damping valve V2 of the present embodiment, the opening pressure of the extension side leaf valve 17 can be changed by adjusting the amount of current supplied to the coil 10, so the damping force generated when the buffer D is extended is adjusted. It is possible.

Furthermore, when the shock absorber D is extended, the rod 3 withdraws from the cylinder 4, so there is a shortage of hydraulic fluid in the cylinder 4 corresponding to the volume of the rod 3 withdrawing. A check valve 24 provided in the reservoir chamber R is opened to supply water from the reservoir chamber R into the cylinder 4. The opening pressure of the check valve 24 is set very low to prevent the pressure inside the cylinder 4 from falling below atmospheric pressure.

Subsequently, when the rod 3 moves downward in FIG. 4 with respect to the cylinder 4 and the shock absorber D is compressed, the piston 5 also moves downward with respect to the cylinder 4 together with the rod 3, and the pressure side chamber R2 is compressed. At the same time, the expansion side chamber R1 is expanded. As the pressure side chamber R2 is compressed, the pressure inside the pressure side chamber R2 increases, and the pressure side leaf valve 15 in the damping valve V1 is pressed by the pressure of the pressure side chamber R2 acting through the pressure side port 5c. The pressure-side leaf valve 15 bends when the force pushing it upward in FIG. 4 due to the pressure in the pressure-side chamber R2 exceeds the urging force of the pressure-side urging member 35, opens the pressure-side port 5c, and causes the valve to pass through the pressure-side port 5c. Provides resistance to oil flow. Furthermore, when the shock absorber D is contracted, the amount of hydraulic oil that the rod 3 enters into the cylinder 4 becomes excessive, so the excess hydraulic oil is transferred to the pressure side damping passage 6a and the pressure side valve 23. It moves to the reservoir room R via. In this way, when the shock absorber D is contracted, the pressure side leaf valve 15 and the pressure side valve 23 provide resistance to the flow of hydraulic oil, so the pressure in the pressure side chamber R2 becomes higher than the pressure in the expansion side chamber R1, and the shock absorber D generates a damping force that suppresses the extension operation. Note that when the shock absorber D is retracted, the growth side leaf valve 17 is maintained in a state seated on the growth side valve seat 5d by the pressure of the compression side chamber R2 and the urging force of the growth side urging member 34, so that the growth side leaf valve 17 is maintained seated on the growth side valve seat 5d. The port 5b is blocked and hydraulic oil does not pass through the expansion side port 5b.

In the damping valve V2 of the present embodiment, the opening pressure of the pressure side leaf valve 15 can be changed by adjusting the amount of current supplied to the coil 10, so the damping force generated when the shock absorber D is contracted can be adjusted. obtain.

As described above, the damping valve V2 includes the expansion side port 5b and the compression side port 5c, the expansion side valve seat 5d that rises from the outer periphery of the opening end of the expansion side port 5b and the compression side port 5c, and surrounds the expansion side port 5b and the compression side port 5c, and the compression side valve. a piston (valve seat member) 5 having a seat 5e; The expansion side leaf valve 17 and the compression side leaf valve 15, and the opposing side which is arranged at intervals on the opposite valve seat member side of the expansion side leaf valve 17 and the compression side leaf valve 15 and faces the expansion side leaf valve 17 and the compression side leaf valve 15. A small diameter portion (shaft member) 3a to which the members 30, 31, the coil 10, the piston 5 and the opposing members 30, 31 are attached, and a small diameter portion 3a disposed between the expansion side leaf valve 17 and the opposing member 30. A valve suppressing member 32 is movable in the axial direction on the outer circumference and comes into contact with the opposite side of the valve seat member of the expansion side leaf valve 17, and a valve suppressing member 32 is disposed between the compression side leaf valve 15 and the opposing member 31 and is attached to the small diameter portion 3a. A valve suppressing member 33 that is movable in the axial direction on the outer circumference and abuts against the side of the compression side leaf valve 15 opposite to the valve seat member, and a valve suppressing member 33 that is interposed between the opposing member 30 and the valve suppressing member 32 and is disposed on the expansion side leaf valve 17. and a growth side urging member 34 that is interposed between the opposing member 31 and the valve suppressing member 33 and urges the compression side leaf valve 15.

The damping valve V2 configured in this manner attaches the expansion side leaf valve 17 and the compression side leaf valve 15 with the expansion side urging member 34 and the compression side urging member 35, which have a magnetorheological elastomer whose elasticity can be changed by the action of a magnetic field. By adopting a damping structure, the damping force can be adjusted. The components necessary for adjusting the damping force are the expansion side biasing member 34, the compression side biasing member 35, and the coil 10, so compared to a large solenoid that has a fixed iron core, a movable iron core, and a spring in addition to the coil. The damping valve V2 can be installed in the piston portion of the shock absorber D because the damping valve V2 is not only small in size but also requires a small number of parts. Therefore, according to the damping valve V2 of this embodiment, even if the damping force can be adjusted, it does not increase in size and can suppress an increase in manufacturing costs.

Further, according to the damping valve V2 of the present embodiment, the coil 10 is provided to replace the spring in the damping valve structure in which a spring is provided between the leaf valve and the opposing member and the damping force cannot be adjusted. Since the damping force can be adjusted simply by interposing the biasing member 35 (34) between the valve 15 (17) and the opposing member 31 (30), it is possible to adjust the damping force inexpensively and easily for a damping valve whose damping force cannot be adjusted. A damping force adjustment function can be added.

Although the preferred embodiments of the present invention have been described in detail above, modifications, variations, and changes can be made without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 1...Buffer body, 2...Outer shell, 3...Rod, 3a...Small diameter part (shaft member), 5...Piston (valve seat member), 5b...Extension side port (port), 5c...pressure side port (port), 5d...extension side valve seat (valve seat), 5e...compression side valve seat (valve seat), 10...coil, 12, 20...・Valve stopper (opposed member), 15... Compression side leaf valve (leaf valve), 16, 35... Compression side biasing member (biasing member), 17... Rebound side leaf valve (leaf valve), 18 , 34... Extension side biasing member (biasing member), 30, 31... Opposing member, 32, 33... Valve suppressing member, D... Shock absorber, R... Reservoir chamber (operation chamber), R1... Rebound side chamber (working chamber), R2... Compression side chamber (working chamber), V, V1, V2... Damping valve

Claims (5)

a valve seat member having a port and a valve seat that rises from the outer periphery of an open end of the port and surrounds the port;
a leaf valve that has an annular shape and is stacked on the valve seat member and can be seated on and taken off from the valve seat;
a facing member disposed at a distance from the valve seat member side of the leaf valve and facing the leaf valve;
a biasing member that is interposed between the leaf valve and the opposing member and includes a magnetorheological elastomer that biases the leaf valve toward the valve seat;
A damping valve comprising: a coil that applies a magnetic field to the biasing member. comprising a shaft member to which the valve seat member and the opposing member are attached;
The leaf valve has an annular shape, and an inner circumferential side is fixed between the valve seat member of the shaft member and the opposing member, and deflection of the outer circumferential side is allowed;
The damping valve according to claim 1, wherein the biasing member is provided between the outer peripheral side of the leaf valve and the opposing member. a shaft member to which the valve seat member and the opposing member are attached;
a valve suppressing member disposed between the leaf valve and the opposing member, movable in the axial direction with respect to the shaft member, and abutting a side of the leaf valve opposite to the valve seat member;
The damping valve according to claim 1, wherein the biasing member is interposed between the opposing member and the valve suppressing member and biases the leaf valve via the valve suppressing member. . The damping valve according to claim 1, wherein the valve seat member and the opposing member are formed of a soft magnetic material. a shock absorber body having an outer shell, a rod that is movably inserted in the outer shell in an axial direction, and at least two working chambers in which liquid moves back and forth by movement of the rod with respect to the outer shell;
A shock absorber comprising: the damping valve according to any one of claims 1 to 4 provided between the working chambers.

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