JP2010144785A - Valve structure for shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve structure for a shock absorber capable of improving ride comfort of a vehicle even if piston speed reaches a high speed area. <P>SOLUTION: This valve structure for the shock absorber includes a channel 7 providing communication between one chamber 41 and an upstream of a port 2a provided on a valve disk 1, a throttle valve 11 provided with a valve element 12 disposed in a middle of the channel 7 capable of reducing a channel area, and a leaf spring 25 applying a pressure of the one chamber 41 on the valve element 12 so as to generate thrust force in a direction reducing the channel area, applying a pressure of another chamber 42 or an intermediate pressure between the pressure of the one chamber 41 and the pressure of another chamber 42 so as to generate thrust force opposing to thrust force by the pressure of the one chamber 41, and biasing the valve element 12 in a direction opposing to the thrust force by the pressure of the one chamber 41, and makes the leaf spring 25 partially abut on the valve element 12 at a circumferential interval. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improved valve structure of a shock absorber.

  Conventionally, this kind of shock absorber valve structure is embodied in, for example, a piston portion of a shock absorber for a vehicle, and an annular leaf valve is laminated on the outlet end of a port provided in the piston portion. A valve that opens and closes a port is known.

  Specifically, for example, as shown in FIG. 13, the valve structure of the shock absorber has a cylindrical shape that fixes the piston P to the piston rod R without fixedly supporting the inner peripheral side of the leaf valve L. A valve structure of a shock absorber is proposed in which the inner periphery of the leaf valve L is slidably contacted with the outer periphery of the piston nut N and the back surface of the leaf valve L is urged by the spring S via the main valve M. However, it is embodied in the expansion side damping valve of the shock absorber (see, for example, Patent Document 1).

In the shock absorber to which this valve structure is applied, as shown in FIG. 14, the inner periphery is fixedly supported when the piston speed when the piston P moves upward is in the low speed region. When the piston speed reaches the middle and high speed range, the pressure of the hydraulic oil passing through the port Po acts on the leaf valve L and the spring S resists the urging force of the spring S. Since the valve L lifts and retreats from the piston P together with the main valve M in the axial direction, the flow path area becomes larger than the shock absorber valve structure in which the inner periphery is fixedly supported, and the damping force is excessive. The ride comfort in the vehicle can be improved.
Japanese Patent Laid-Open No. 9-291196 (FIG. 1)

  However, in the proposed valve structure as described above, although it is a useful technique in terms of improving riding comfort in a vehicle, it may be pointed out that there are the following problems.

  This is because, for example, when the piston speed when the piston P moves upward reaches the high speed region, in the conventional shock absorber valve structure, the leaf valve L moves backward from the piston P in the axial direction according to the piston speed. The damping coefficient does not increase.

  Therefore, when the piston speed reaches the high speed region, the damping force is insufficient, and the vibration is not sufficiently suppressed, so that the riding comfort in the vehicle is deteriorated.

  Also, in the conventional shock absorber valve structure, the leaf valve L is urged by the coil spring S, so the entire length of the piston portion including the coil spring S is increased. If the stroke length, which is the extendable range of the shock absorber, is shortened and the stroke length is to be secured, the overall length of the shock absorber is lengthened, and the mountability on the vehicle is deteriorated.

  When considering shortening the total length of the piston part, it may be possible to use a leaf spring instead of a coil spring, but the urging force of the leaf spring shows a non-linear characteristic with respect to the amount of deflection of the outer periphery, Even with a small amount of deflection, the leaf valve may be excessively biased, and it is difficult to replace the leaf spring with a coil spring.

  Therefore, the present invention was devised to improve the above problems, and the object of the present invention is to provide a shock absorber capable of satisfying both the riding comfort in a vehicle and the stroke length in the shock absorber. It is to provide a valve structure.

  In order to solve the above-described object, the problem-solving means in the present invention includes a valve disk having a port that separates the one chamber and the other chamber in the shock absorber and communicates the one chamber with the other chamber; In the valve structure of the shock absorber provided with a leaf valve that is stacked on the side surface of the other chamber of the valve disk and opens and closes the port, a flow path that connects the one chamber and the upstream of the port, and a flow path that is provided in the middle of the flow path. And a throttle valve having a valve body capable of reducing the passage area, and the pressure of the one chamber is applied to the valve body so as to give a thrust in the direction of reducing the flow path area, and the thrust due to the pressure of the one chamber is opposed. A leaf spring is provided that applies a pressure in the other chamber or an intermediate pressure between the pressure in the one chamber and the pressure in the other chamber so as to apply thrust, and urges the valve body in a direction opposite to the thrust due to the pressure in the one chamber. The Characterized in that is brought into contact with partially valve body at intervals in a direction.

  In order to solve the above-described object, another problem-solving means in the present invention is a port on one side that separates one chamber from the other chamber and communicates the one chamber with the other chamber in the shock absorber. And a valve disc having a port on the other side, a leaf valve on one side stacked on the side surface of the other chamber of the valve disc to open and close a port on one side, and a side plate stacked on the side surface of the one chamber of the valve disc In the valve structure of the shock absorber provided with the leaf valve on the other side for opening and closing the other port, the one-side flow path communicating the one chamber and the upstream of the one-side port, and the upstream of the other chamber and the other-side port The other side flow path, the one side throttle valve provided with a valve body provided in the middle of the one side flow path and capable of reducing the flow area, and the middle of the other side flow path. It is possible to reduce the flow area The pressure of one chamber is applied to the throttle valve on the other side provided with the valve body, and the pressure on the one side is applied to the valve body on one side so as to apply thrust in the direction of reducing the flow path area, The pressure of the other chamber or the pressure of the one chamber and the pressure of the other chamber is applied so as to apply the opposing thrust, and the pressure of the other chamber is applied to the valve body on the other side in order to reduce the flow path area. The pressure of one chamber or an intermediate pressure between the pressure of one chamber and the pressure of the other chamber is applied to the valve body on the other side so as to give a thrust opposite to the thrust due to the pressure of the other chamber, and the valve body on one side is A leaf spring on one side for urging in a direction opposite to the thrust due to the pressure of the other, and a leaf spring on the other side for urging the valve body on the other side in a direction opposite to the thrust due to the pressure in the other chamber, In contact with the valve body at intervals in the circumferential direction. To.

  According to the valve structure of the shock absorber of the present invention, in the valve structure, when the piston speed is in the medium speed region, the piston speed is reduced when the piston speed reaches the high speed region while keeping the damping force low. The damping force can be made larger than when it is in the middle speed range, and even when the piston speed reaches the high speed range, the damping force will not be insufficient, vibration will be sufficiently suppressed, and the ride comfort in the vehicle Can be improved.

  In addition, in a situation where the amplitude at which the shock absorber is fully extended is large and the piston speed reaches the high speed region, the damping force generated by the shock absorber can be increased. It is possible to reduce the impact at the time of maximum extension.

  Furthermore, in this valve structure, the leaf springs are partially abutted against the valve body at intervals in the circumferential direction, so that the urging force of the leaf springs has a characteristic close to linear with respect to the deflection amount of the outer circumference. It is possible to solve the problem of excessively urging the valve body with a slight amount of deflection, and in addition, it prevents the stress generated inside the leaf spring from becoming excessive with a slight amount of deflection. Therefore, a large stroke amount of the valve body can be secured. Therefore, the leaf spring can be replaced with a coil spring, the overall valve length of the shock absorber can be shortened, and the problem of shortening the stroke length of the shock absorber can be eliminated.

  In addition, since the configuration that urges the back of the leaf valve with a coil spring is not adopted, there is no concern that the damping characteristics of each product will vary due to variations in the urging force of the spring. Improves reliability and stability.

  The valve structure of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to an embodiment is embodied. FIG. 2 is a model diagram showing a deformed state of the leaf spring. FIG. 3 is a diagram showing the characteristics of the amount of bending and the urging force when the entire circumference of the leaf spring is urged against the valve body. FIG. 4 is a view showing a state in which a leaf spring in which the valve structure of the shock absorber according to the embodiment is embodied is bent to urge the valve body. FIG. 5 is a diagram illustrating the characteristics of the amount of deflection and the urging force of the leaf spring in which the valve structure of the shock absorber according to the embodiment is embodied. FIG. 6 is a diagram illustrating a result of analyzing the urging force with respect to the bending amount of the leaf spring including the convex portions having different circumferential widths. FIG. 7 is a diagram showing a result of analyzing the maximum value of the internal stress in the leaf spring with respect to the bending amount of the leaf spring provided with convex portions having different circumferential widths. FIG. 8 is a diagram illustrating a damping characteristic in the shock absorber in which the valve structure of the shock absorber according to the embodiment is embodied. FIG. 9 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to a modification of the embodiment is embodied. FIG. 10 is a plan view of a leaf spring in which a valve structure according to another modification of the embodiment is embodied. FIG. 11 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to another modification of the embodiment is embodied. FIG. 12 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to another embodiment is embodied.

  As shown in FIG. 1, the valve structure of the shock absorber in one embodiment is embodied in both the expansion side and pressure side damping valves of the piston portion of the shock absorber. Piston 1 which is a valve disk having a port 2a on one side and a port 2b on the other side that separate the chamber 42 and communicate with the one chamber 41 and the other chamber 42, and is laminated on the side surface of the other chamber of the piston 1 One side leaf valve 10a that opens and closes one side port 2a, the other side leaf valve 10b that is stacked on the side surface of one chamber of the piston 1 and opens and closes the other side port 2b, one chamber 41 and one side Provided in the middle of the one-side flow path 7 communicating with the upstream of the other port 2a, the other-side flow path 8 communicating with the other chamber 42 and the upstream of the other port 2b, and the one-side flow path 7. Reduced flow area One side throttle valve 11 having a valve body 12 that can be used, and the other side throttle valve 13 having a valve body 14 that is provided in the middle of the other side flow path 8 and that can reduce the flow path area. And the pressure chamber 18 on one side for energizing the valve body 12 in the throttle valve 11 on the one side in a direction in which the pressure in the other chamber 42 is guided and the flow passage area is not reduced by the pressure, The pressure chamber 19 on the other side energizes the valve body 14 in the throttle valve 13 on the other side and the pressure in the one chamber 41 on the other side of the valve body 14 in the direction in which the pressure is guided and the flow passage area is not reduced by the pressure. And a leaf spring 29 on the other side for urging the valve body 14 on the other side in a direction opposite to the thrust due to the pressure of the other chamber 42. Configured.

  In this document, in order to facilitate the description of each part, the member that functions when the port 2a on one side is opened is assumed to be a member on one side and functions when the port 2b on the other side is opened. About the member, the member of the same name is distinguished as a member of the other side.

  On the other hand, a shock absorber in which the valve structure is embodied is well known and will not be described in detail, but specifically, for example, a cylinder 40 and a head member (not shown) that seals the upper end of the cylinder 40. ), A piston rod 5 that slidably passes through a head member (not shown), a piston 1 that is inserted into the tip 5a of the piston rod 5 that forms a shaft member, and is fixed to the tip 5a, and a cylinder 40 An upper chamber 41 in FIG. 1, a lower chamber 42 in the lower side in FIG. 1, a sealing member (not shown) that seals the lower end of the cylinder 40, and the cylinder 40 protrude from the cylinder 40. A cylinder or an air chamber (not shown) that compensates for a change in the cylinder volume corresponding to the volume of the piston rod 5 is provided, and the cylinder 40 is filled with a fluid, specifically, hydraulic oil.

  In the valve structure described above, when the piston 1 moves up and down in FIG. 1 with respect to the cylinder 40 and hydraulic oil flows between the one chamber 41 and the other chamber 42 via the ports 2a and 2b. The leaf valves 10a and 10b respectively corresponding to the flow of the hydraulic oil are resisted to cause a predetermined pressure loss, thereby functioning as a damping force generating element that generates a predetermined damping force in the shock absorber.

  Hereinafter, the valve structure will be described in detail. The piston 1 serving as a valve disk is formed in an annular shape, and operates in reverse to the port 2a on one side that allows hydraulic oil to pass from the one chamber 41 to the other chamber 42. The other side port 2b that allows the oil to pass from the other chamber 42 to the one chamber 42, the windows 3a and 3b respectively connected to the outlet ends of the ports 2a and 2b, and the outlet ends of the ports 2a and 2b Annular valve seats 1a and 1b formed on the outer peripheral sides of the windows 3a and 3b are provided.

  Further, in this embodiment, the open ends of the ports 2a and 2b are arranged on the outer peripheral side of the windows 3a and 3b so as not to be blocked by the leaf valves 10a and 10b stacked on the piston 1, respectively. . The one side port 2a is not closed by the other side leaf valve 10b, and the other side port 2b is not limited to the one shown in the figure for its arrangement and shape unless it is closed by the one side leaf valve 10a. For example, a configuration may be adopted in which the ports 2a and 2b are arranged on the same circumference and the valve seats 1a and 1b are so-called petal types.

  As described above, the tip 5a of the piston rod 5 of the shock absorber is inserted into the inner peripheral side of the piston 1, and the tip 5a of the piston rod 5 is protruded downward in FIG. Further, the outer diameter of the tip 5a of the piston rod 5 is set to be smaller than the outer diameter on the upper side in FIG. 1 from the tip 5a, and a step portion 5b is formed at a portion where the outer diameters of the upper side and the tip 5a are different. Yes.

  Furthermore, the piston rod 5 has two vertical holes 15a and 16a that open from the lower end of the tip 5a, and corresponding vertical holes 15a and 16a that open from the side portion above the step 5b of the piston rod 5 and correspond to each other. The horizontal hole 15b is closed by the plug 17a to form a communication passage 15 that communicates only with the other chamber 42 by the paired vertical hole 15a and the horizontal hole 15b. The lower end of the vertical hole 16a is closed by a plug 17b to form a communication path 16 that communicates only with the one chamber 41 by the paired vertical hole 16a and horizontal hole 16b.

  Returning, leaf valve 10a, 10b laminated | stacked up and down in FIG. 1 of the piston 1 is comprised as a lamination | stacking leaf valve by laminating | stacking several sheets formed in cyclic | annular form, The leaf valve 10a of one side is The valve seat 1a formed on the other chamber 42 side of the piston 1 is in contact with the outlet end of the port 2a on one side, and the leaf valve 10b on the other side is formed on the one chamber 41 side of the piston 1. The outlet end of the port 2b on the other side is closed by coming into contact with 1b. In this embodiment, the leaf valves 10a and 10b are configured as laminated leaf valves. However, the number of the annular plates depends on the damping characteristics (relationship of the damping force to the piston speed) realized by this valve structure. Depending on the attenuation characteristics generated in the shock absorber, a plurality of sheets or only one sheet may be used, and the outer diameter of each leaf may be set differently depending on the attenuation characteristics generated in the shock absorber. it can.

  Further, although not shown in detail, a known notch is formed on the outer periphery of the leaf valves 10a and 10b seated on the valve seats 1a and 1b, or is formed by being stamped on the valve seats 1a and 1b. An orifice is provided.

  Subsequently, the spacer 31, the partition member 21, the large-diameter holding member 22, the spacer 32, the annular leaf spring 25, the spacer 33, the small-diameter holding member 23, and the upper part of the leaf valve 10 b on the other side in FIG. A stopper 24 is stacked. Further, a cylindrical valve body 12 in the throttle valve 11 on one side is slidably mounted on the outer periphery of the large-diameter holding member 22 and the small-diameter holding member 23 above the partition member 21 in FIG. The body 12 is urged upward in FIG. 1 by a leaf spring 25, and the upper end of the body 12 abuts against the stopper 24, and further upward movement of the valve body 12 is restricted.

  On the other hand, a spacer 34, a partition member 26, a large-diameter holding member 27, a spacer 35, an annular leaf spring 29, a spacer 36, a small-diameter holding member 28 and a stopper are provided below the leaf valve 10a on one side in FIG. 37, and the cylindrical valve element 14 of the throttle valve 13 on the other side is slidable on the outer periphery of the large-diameter holding member 27 and the small-diameter holding member 28 below the partition member 26 in FIG. The valve body 14 is mounted and urged downward in FIG. 1 by a plate spring 29, and the lower end of the valve body 14 abuts against the stopper 37 to restrict further downward movement of the valve body 14.

  And the stopper 24, the small diameter holding member 23, the spacer 33, the annular leaf spring 25, the spacer 32, the large diameter holding member 22, the valve body 12, the partition member 21, the spacer 31, the leaf valve 10b on the other side, the piston 1. Leaf valve 10a on one side, spacer 34, partition member 26, large diameter holding member 27, spacer 35, annular leaf spring 29, spacer 36, small diameter holding member 28, valve body 14 and stopper 37 Each member is sequentially assembled to the tip 5 a of the piston rod 5, and is sandwiched between a piston nut 30 screwed into a screw groove 5 c provided at the tip 5 a and a step portion 5 b of the piston rod 5 and fixed to the piston rod 5. Is done.

  That is, in this valve structure, the spacer 31, the partition member 21, the large-diameter holding member 22, the spacer 32, the annular leaf spring 25, the spacer disposed in the one chamber 41 above the piston 1. 33, the structure of the small diameter holding member 23, the valve body 12 and the stopper 24, and the spacer 34, the partition member 26, the large diameter holding member 27, the spacer 35, and the annular leaf spring disposed in the other chamber 42 on the lower side. 29, the spacer 36, the small diameter holding member 28, the valve body 14, and the stopper 37 are in a line-symmetric relationship with the piston 1 as a boundary and upside down.

  The partition member 21 disposed above the piston 1 in FIG. 1 has a bottom portion 21a and a cylindrical portion 21b, and has a bottomed cylindrical shape. The cylindrical member 21b is fitted to the outer periphery of the piston 1 so as to fit the piston. 1 and the chamber R1 is partitioned from the one chamber 41 with the piston 1. Further, the bottom 21a of the partition member 21 has a hole 21c into which the tip 5a of the piston rod 5 can be inserted, a plurality of through holes 21d provided on the same circumference and penetrating the bottom 21a, and on the same circumference. And a plurality of through holes 21e disposed through the bottom 21a and disposed on the inner peripheral side of the through hole 21d, and an annular valve seat 21f provided between the through hole 21d and the through hole 21e. The channel 7 on one side is branched into the main channel 7a and the sub channel 7b by the through holes 21d and 21e, and the main channel 7a and the sub channel 7b forming the channel 7 on the one side The one chamber 41 communicates with the upstream of the port 2a on one side through R1.

  On the other hand, the partition member 26 disposed below the piston 1 in FIG. 1 is similarly provided with a bottom portion 26a and a cylindrical portion 26b, and has a bottomed cylindrical shape, and the cylindrical portion 26b is fitted to the outer periphery of the piston 1. The chamber R2 is separated from the other chamber 42 between the piston 1 and the piston 1. Further, the bottom 26a of the partition member 26 has a hole 26c into which the tip 5a of the piston rod 5 can be inserted, a plurality of through holes 26d provided on the same circumference and penetrating the bottom 26a, and the same circumference. And a plurality of through holes 26e disposed on the inner peripheral side of the through hole 26d and an annular valve seat 26f provided between the through hole 26d and the through hole 26e. The other flow path 8 is branched into the main flow path 8a and the sub flow path 8b through the through holes 26d and 26e, and the main flow path 8a and the sub flow path 8b forming the other flow path 8 The other chamber 42 communicates with the upstream side of the port 2b on the other side through R2.

  Subsequently, the valve body 12 in the throttle valve 11 on one side is formed into a cylindrical shape, and a large-diameter portion 12a formed by setting the inner diameter on the partition member 21 side to a large diameter and the inner diameter on the counter-partition member side in a small diameter. The valve element 12 is configured to be fixed in the piston rod 5 and fixed in the axial direction with respect to the piston 2 which is a valve disk. The outer periphery of the large-diameter holding member 22 is slidably mounted on the outer periphery of the large-diameter holding member 22, and the small-diameter portion 12 b is fixed to the piston rod 5 and is slid on the outer periphery of the small-diameter holding member 23. By being mounted freely, the large diameter holding member 22 and the small diameter holding member 23 can be moved in the vertical direction in FIG. Pressure chamber 1 on one side during Defining a.

  In this case, the large-diameter holding member 22 is formed in an annular shape and the inner peripheral portion 22a fixed to the piston rod 5 is set to be thick, and an annular groove 22b formed in the inner periphery, and an opening from the inner periphery. And a passage 22c leading to an end facing the pressure chamber 18 on one side.

  The large-diameter holding member 22 is laminated on the partition member 21 and is fixed to the tip 5a of the piston rod 5 so that the annular groove 22b is not movable in the axial direction with respect to the piston 1. 5 so as to face the through hole 15c branched from the vertical hole 15a of the communication passage 15 provided in the communication passage 15. As a result, the pressure chamber 18 on one side communicates with the other chamber 42 via the communication passage 15, The pressure in the other chamber 42 is guided into the pressure chamber 18.

  Further, the outer shape of the inner peripheral portion 22a of the large-diameter holding member 22 is set to a diameter that does not block the through hole 21e even when the outer peripheral portion 22a is stacked on the partition member 21, and the large-diameter holding member 22 holds the large diameter by the thickness of the inner peripheral portion 22a. A gap is formed between the member 22 and the partition member 21 so that the one chamber 41 communicates with the sub flow path 7b.

  On the other hand, the small-diameter holding member 23 has an annular shape, and the inner peripheral side is fixed to the piston rod 5. The small-diameter holding member 23 and the large-diameter holding member 22 sandwich the spacer 32, the leaf spring 25, and the spacer 33. ing. That is, the leaf spring 25 is housed in the pressure chamber 18 on one side, and the outer periphery that is fixed on the inner peripheral side and that is the free end is bent.

  The leaf spring 25 is configured by laminating a plurality of annular plates, and the outer periphery of the leaf spring 25 is laminated on a step portion 12c formed at the boundary between the large diameter portion 12a and the small diameter portion 12b. The valve body 12 is bent in contact with the ring 38 provided with the portion 38 a and biases the valve body 12 in a direction away from the partition member 21. That is, the valve body 12 is urged by the leaf spring 25 via the ring 38.

  The ring 38 includes three convex portions 38a facing the leaf spring 25. The ring 38 is sandwiched between the leaf spring 25 and the step portion 12c of the valve body 12, and the valve body 12 is displaced in the vertical direction in FIG. Further, the ring 38 is displaced together with the valve body 12 while maintaining contact with the valve body 12, and the ring 38 forms a part of the valve body 12.

  Further, the spacer 31 is formed by laminating a plurality of annular plates having a smaller diameter than the leaf valve 10b, and the number of the annular plates can be arbitrarily determined according to the thickness of the leaf valve 10b. It may be constituted only by a thick annular plate. Even in the spacers 32 and 33, a plurality of annular plates having a smaller diameter than the leaf spring 25 are laminated, and the number of the annular plates laminated is arbitrary according to the thickness of the leaf spring 25. Alternatively, it may be composed of only one thick annular plate.

  Returning, the valve body 12 is urged upward in FIG. 1 by the leaf spring 25, and is arranged at the uppermost position in the figure that is regulated by the stopper 24 in a state where no other force acts. That is, the valve body 12 is disposed in the one chamber 41 and is urged downward by the pressure of the one chamber 41 acting as the pressure receiving area of the upper surface in FIG. 1 of the small diameter portion 12b. The pressure of the one chamber 41 acting as the pressure receiving area in FIG. 1, the pressure of the pressure chamber 18 on the one side acting as the pressure receiving area of the lower surface in FIG. It is energized upward. Therefore, the pressure in the one chamber 41 is urged downward with the area surrounded by the inner edge of the large diameter portion 12a and the inner edge of the small diameter portion 12b (equal to the area of the stepped portion 12c) as a pressure receiving area. In addition, the pressure in the pressure chamber 18 on one side urges the valve body 12 upward with the area surrounded by the inner edge of the large diameter portion 12a and the inner edge of the small diameter portion 12b as a pressure receiving area.

  The groove 12d provided on the upper surface of the small-diameter portion 12b of the valve body 12 guides the pressure in the one chamber 41 to the contact portion through the groove 12d even when the valve body 12 is in close contact with the stopper 24. The pressure in the one chamber 41 can be applied to the entire upper surface of the valve body 12 in FIG.

  The throttle valve 11 on one side includes a valve body 12, a leaf spring 25, and an annular valve seat 21 f provided on the partition member 21, and the valve body 12 resists the urging force of the leaf spring 25. 1, the large-diameter portion 12a approaches the annular valve seat 21f provided on the partition member 21 so as to reduce the flow passage area in the sub flow passage 7b. When the lower end in FIG. 1 of the large-diameter portion 12a of the body 12 is seated on the annular valve seat 21f, the communication between the one chamber 41 and the room R1 by the sub-channel 7b is blocked, and the channel 7 on the one side The channel area is reduced to the channel area of the main channel 7a.

  That is, a downward thrust in FIG. 1 that acts to reduce the flow path area acts on the valve body 12 due to the differential pressure between the one chamber 41 and the other chamber 42 acting on the area of the stepped portion 12c. When the difference from the pressure in the chamber 42 increases, the valve element 12 moves downward in FIG. 1 against the spring force of the leaf spring 25 and operates to reduce the flow area of the flow path 7 on one side. In the case of this embodiment, in order to apply each thrust to the valve body 12 as described above, this is realized by providing the pressure chamber 18 on one side.

  Specifically, in the expansion stroke of the shock absorber in which the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the valve body 12 in the throttle valve 11 on one side is shown by the pressure in the one chamber 41 that is at a high pressure. The downward force in FIG. 1, which is the resultant force of the upward thrust in FIG. 1 due to the differential force between the downward thrust in 1 and the pressure in the other chamber 42, which is a low pressure guided to the pressure chamber 18 on one side, An upward force in FIG. 1 acts. When the resultant force exceeds the force of the leaf spring 25, the valve body 12 in the throttle valve 11 on one side is moved downward in FIG. 1 on the partition member 21 side and passes through the partition member 21. The channel area of the sub-channel 7b communicating with the hole 21e is narrowed to reduce the channel area of the channel 7 on one side.

  That is, in the throttle valve 11 on one side, when the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the valve body 12 moves downward in FIG. In the case of this embodiment, the flow passage area is reduced. Finally, the sub flow passage 7b is cut off, and only the main flow passage 7a communicates only the one chamber 41 and the upstream of the one port 2a. . In the case of this embodiment, the throttle valve 11 on one side closes the sub-flow path 7b in the flow path 7 on the one side, so the final flow when the flow path 7 on the one side is squeezed to the maximum extent. However, it is advantageous that a single flow path can be throttled by the throttle valve 11 on one side without branching the flow path 7 on one side. Also good. When narrowing a single flow path, if the flow path is completely blocked, the communication between the one chamber 41 and the other chamber 42 is cut off, so that the flow path may not be completely blocked.

  And in this invention, the leaf | plate spring 25 is used as a source which produces the thrust which opposes the downward thrust in FIG. 1 by the pressure of the one chamber 41 and the other chamber 42 which act on the valve body 12, The said valve body 12 Displacement from the position at the uppermost position that contacts the stopper 24 and maximizes the flow area of the flow path 7 on one side to the position that contacts the annular valve seat 21f and minimizes the flow area of the flow path 7 Until this is done, the area of the annular gap between the partition member 21 and the valve body 12, that is, the flow passage area of the sub flow passage 7b is not changed suddenly, and gradually, as the pressure in the one chamber 41 increases. It can be gradually reduced. That is, the valve body 12 approaches the annular valve seat 21f of the partition member 21 as the pressure difference in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount and the pressure difference increases, and the flow passage 7 on one side is moved. It works to squeeze a lot.

  Further, when the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the valve body 12 starts to throttle the sub flow path 7b. The predetermined amount is set by the pressure in the one chamber 41 and the pressure in the other chamber 42. However, in this case, the piston speed of the shock absorber is a boundary between a medium speed and a high speed. Is set to

  Further, by using the leaf spring 25, the length in the vertical direction in FIG. 1, which is the axial direction, can be set shorter than that of the coil spring, and the total length of the piston portion including the throttle valve 11 on one side can be shortened. The stroke length in the shock absorber can be easily secured. Further, in this embodiment, since the configuration in which the leaf spring 25 is accommodated in the pressure chamber 18 on one side is adopted, the leaf spring 25 can be arranged in parallel on the inner periphery of the valve body 12. In this respect as well, the overall length of the piston portion including the throttle valve 11 on one side can be set short, and the stroke length in the shock absorber can be more easily ensured.

  However, when the valve body 12 is simply urged by the leaf spring 25, the valve body 12 is greatly urged even by a small amount of deflection, so that a large stress is generated in the leaf spring 25, and the load on the leaf spring 25 is large. It is difficult to ensure the stroke of the body 12. This point will be described with reference to the model diagram shown in FIG.

  As shown in FIG. 2, the stepped portion, which is the seat portion that contacts the leaf spring 25 of the valve body 12, is simply formed into an annular shape and can be brought into contact with the leaf spring 25. As shown in FIG. This is the same as bringing the leaf spring X at the end into contact with the annular seat Y in the valve body. Then, in the unloaded state, the entire circumference of the leaf spring X is brought into contact with the seat portion Y, the leaf spring X and the seat portion Y are approached in the axial direction, the outer periphery of the leaf spring X is bent, and the seat portion Y is urged. In this case, the outer edge diameter of the leaf spring X is reduced in accordance with the amount of deflection, and the plate spring X is deformed by bending in the circumferential direction. There is no escape space which is restrained and allows deformation in the circumferential direction of the leaf spring X, which generates a large reaction force, and the urging force of the leaf spring X is relative to the amount of deflection of the outer circumference as shown in FIG. Non-linear characteristics will be exhibited.

  The amount of deflection indicates the stroke amount at which the seat portion Y approaches the leaf spring X, and the urging force indicates the force that the leaf spring X acts on the seat portion Y with respect to the approach.

  Further, it has been found that the leaf spring X has a large stress acting on the inside even with a slight amount of deflection, and it is difficult to increase the stroke amount of the seat portion Y in consideration of the allowable stress.

  In order to eliminate such problems, the inventor of the present invention, as a result of diligent efforts and research, has tried not to restrain the circumferential wavy deformation that occurs when the outer periphery of the leaf spring X is bent. For example, it was found that the urging force of the leaf spring X is linear with respect to the amount of bending of the outer periphery, and the internal stress with respect to the amount of bending can be reduced.

  Then, by causing the leaf springs to partially abut against the valve body at intervals in the circumferential direction, a space in which the circumferential undulation deformation portion caused by a decrease in the outer diameter due to bending deformation of the leaf springs escapes. It has been found that it can be provided so as not to be restrained, and the urging force of the leaf spring can be made to have a characteristic close to linear with respect to the amount of bending of the outer periphery, and the internal stress with respect to the amount of bending can be reduced.

  Based on the above knowledge, in order to make the leaf spring 25 partially contact the valve body 12 at intervals in the circumferential direction, in the valve structure of the embodiment, the valve body 12 is made of the leaf spring. 25 is provided with a ring 38, and the ring 38 is provided with convex portions 38 a that protrude downward at equal intervals at three locations on the circumference that are smaller than the outer diameter of the leaf spring 25. .

  The leaf spring 25 abuts against the convex portion 38 a of the ring 38 in a state where the initial deflection is applied, and applies a biasing force to the valve body 12 via the ring 38.

  Since the ring 38 comes into contact with the valve body 12 and is displaced together with the valve body 12, the leaf spring 25 does not contact the valve body 12 over the entire circumference and does not apply an urging force. Only the contacted portion abuts on the valve body 12 to urge the valve body 12, and the leaf spring 25 partially abuts on the valve body 12 at intervals in the circumferential direction via the ring 38. Yes. As described above, the concept in which the leaf spring 25 is partially brought into contact with the valve body 12 is substantially integrated with the valve body 12 that is displaced together with the valve body 12 while maintaining contact with the valve body 12 like the ring 38. Indirect contact between the leaf spring 25 and the valve body 12 through a member to be formed is also included.

  In the valve structure configured as described above, when the valve body 12 is moved downward in FIG. 1, the leaf spring 25 is pressed by the convex portion 38 a to bend the outer periphery, and the valve body 12 is larger in the upward direction in FIG. 1. It will give power.

  When the outer periphery of the leaf spring 25 is bent, as described above, the outer diameter becomes smaller. In this case as well, as shown in FIG. 4 is not pressed over the entire circumference but is partially pressed by the convex portion 38a, the portion b facing between the convex portion 38a and the convex portion 38a generates a wave that protrudes downward in FIG. However, the part b does not contact between the convex part 38a and the convex part 38a of the ring 38, and the deformation of the part b is not easily restricted. In FIG. 4, in order to facilitate understanding of the deformed state of the leaf spring 25, the leaf spring 25 is disposed on the upper side, and only a part of the valve body 12 is extracted.

  Further, the portion c of the leaf spring 25 facing the convex portion 38a is pressed upward by the convex portion 38a and the portion b facing the convex portion 38a undulates downward in FIG. Although a convex wave is generated, a ring 38 having a convex portion 38a is laminated on the step portion 12c of the valve body 12, and the outer periphery of the leaf spring 25 slides in the circumferential direction of the convex portion 38a. The edges 38b, 38b are supported from below in FIG. 4, and deformation of the portion c undulating upward in FIG. 4 is not limited.

  Therefore, since the circumferential deformation of the leaf spring 25 is less likely to be limited by the ring 38, the biasing force due to the circumferential deformation of the leaf spring 25 is suppressed from acting on the valve body 12, The urging force acting on the valve body 12 is dominated by the outer periphery bending of the leaf spring 25, and the urging force of the leaf spring 25 is substantially proportional to the outer periphery bending amount as shown by the solid line in FIG. It will show the characteristic.

  In the valve structure according to the embodiment, as described above, the leaf springs 25 are partially in contact with the valve body 12 at intervals in the circumferential direction. It becomes possible to make the characteristic close to linear with respect to the amount of bending of the outer periphery, so that the problem of excessively urging the valve body 12 with a slight amount of bending can be eliminated. Since the undulation deformation in the direction is not limited, it is possible to prevent the stress generated inside the leaf spring 25 from being excessively small with a slight amount of deflection, and to ensure a large stroke amount of the valve body 12.

  Therefore, in the valve structure of the shock absorber in one embodiment, even if the leaf spring 25 is used, the urging force that urges the valve body 12 does not become excessive, and the stroke amount of the valve body 12 can be secured. Therefore, it can replace with a coil spring, the valve | bulb full length of a shock absorber can be shortened, and the malfunction that the stroke length of a shock absorber becomes short can also be eliminated.

  Furthermore, since a linear urging force can be exhibited with respect to the amount of deflection, it is possible to eliminate the problem that the urging force varies for each solid, and the adjustment of the urging force for urging the valve body 12 is also very high. It becomes easy.

  In the case of this embodiment, the convex portions 38a are provided at equal intervals on the circumference of the ring 38, so that the circumferential deformation of the leaf spring 25 is not distorted, and the leaf spring 25 is not distorted. It is reliably avoided that the urging force due to the undulation deformation is superimposed on the urging force, and the urging force of the leaf spring 25 is also biased to be applied to the valve body 12.

  Further, in the case of this embodiment, the convex portion 38a has its inner peripheral edge arranged on the same circumference so that the support points for supporting the leaf spring 25 are on the same circumference. Although it is considered that the urging force that presses 38a does not vary, the convex portions 38a may be arranged at intervals in the circumferential direction, so that the inner peripheral edge is not necessarily arranged on the same circumference. Good.

  Next, the degree of the circumferential width at the inner edge of the convex portion 38a formed on the ring 38 will be described.

  FIG. 6 is a diagram showing the urging force with respect to the amount of bending when the ring 38 having the convex portions 38 a having different circumferential widths is urged by the leaf spring 25. Specifically, the leaf spring 25 has an inner diameter of 12.5 mm, an outer diameter of 25 mm, a thickness of 0.114 mm, and three convex portions 38a are installed on the ring 38 at equal intervals in the circumferential direction. The urging force with respect to the amount of bending when the ring 38 is urged by the leaf spring 25 under the condition that the inner edge of the portion 38a is arranged on a circumference having a diameter of 24 mm and the convex portion 38a is concentrically pressed against the leaf spring 25. Is analyzed.

  FIG. 7 is a diagram showing the maximum value of the internal stress in the leaf spring 25 with respect to the amount of bending when the ring 38 having the convex portions 38 a having different circumferential widths is urged by the leaf spring 25. Specifically, the leaf spring 25 has an inner diameter of 12.5 mm, an outer diameter of 25 mm, a thickness of 0.114 mm, and three convex portions 38a are installed on the ring 38 at equal intervals in the circumferential direction. The urging force with respect to the amount of bending when the ring 38 is urged by the leaf spring 25 under the condition that the inner edge of the portion 38a is arranged on a circumference having a diameter of 24 mm and the convex portion 38a is concentrically pressed against the leaf spring 25. Is analyzed.

  In FIGS. 6 and 7, the circumferential width of the convex portion 38 a is 4.02 mm for sample 1 (the circumferential width between the convex portions 38 a is 21.11 mm), and 6.06 mm for sample 2 (each convex portion). The circumferential width between the portions 38a is 19.07 mm), sample 3 is 8.16 mm (the circumferential width between the convex portions 38a is 16.98 mm), and sample 4 is 10.31 mm (each convex portion 38a). In the sample 5, the width in the circumferential direction is 14.82 mm, 13.22 mm in the sample 5 (the circumferential width between the convex portions 38a is 11.91 mm), and in the sample 6, 17.51 mm (between the convex portions 38a) The circumferential width is 7.62 mm), sample 7 is 20.35 mm (circumferential width between the convex portions 38a is 4.78 mm), and sample 8 is 23.64 mm (circumferential direction between the convex portions 38a). The width is 1.49 mm) and each sun It is shown in FIGS. 6 and 7 the analysis result of each Le. Sample 9 shows the analysis result when the convex portion 38a is eliminated and the entire circumference of the leaf spring 25 is pressed against the valve holding member.

  As can be understood from FIG. 6, the entire circumference of the leaf spring 25 is up to the sample 7 in which the circumferential width of the convex portions 38a is 20.35 mm (the circumferential width between the convex portions 38a is 4.78 mm). For the sample 9 pressed against the valve holding member, the inclination of the line indicating the relationship of the urging force with respect to the deflection amount becomes smaller and the urging force approaches a proportional relationship with respect to the deflection amount, and the circumferential direction of the convex portion 38a It can be seen that as the width becomes smaller, the urging force with respect to the deflection amount decreases.

  As can be understood from FIG. 7, the entire circumference of the leaf spring 25 is up to the sample 4 where the circumferential width of the convex portions 38 a is 20.35 mm (the circumferential width between the convex portions 38 a is 4.78 mm). For the sample 9 pressed against the valve restraining member, the inclination of the line indicating the relationship of the maximum value of the internal stress with respect to the deflection amount becomes smaller, and the smaller the circumferential width of the convex portion 38a, the more the internal stress with respect to the deflection amount. It can be seen that the maximum value decreases.

  From the above results, the circumferential width at the inner edge of the convex portion 38a formed on the ring 38 may be set to such an extent that a gap allowing the undulation deformation of the leaf spring 25 can be formed between the convex portions 38a. When aiming at the effect of approximating the urging force with respect to the deflection amount of 25 to a proportional relationship, the ratio of tightening to the circumferential length of a circle passing through the inner edge of the convex portion 38a of the total extension of the circumferential width of all the convex portions 38a. It can be seen that it is sufficient to set the value to be about 81% or less. In order to reduce the internal stress with respect to the amount of bending of the leaf spring 25, the circumferential length of the circle passing through the inner edge of the convex portion 38a of the total extension of the circumferential width of all the convex portions 38a is generally tightened. It can be seen that the ratio may be set to about 41% or less.

  In the above description, the number of the convex portions 38a is three. However, if the number of the convex portions 38a is two or more, a gap that allows the wave spring deformation of the leaf spring 25 is formed between the convex portions 38a. It has been found by the inventors' research that this is effective.

  Further, although the edges 38 b and 38 b of the convex portion 38 a are oriented in parallel to each other, the edges 38 b and 38 b may be set in a direction toward the center of the ring 38.

  Furthermore, the setting of the height of the convex part 38b is demonstrated. As described above, when the outer periphery of the leaf spring 25 is bent, the outer diameter becomes smaller and the wave is deformed in the circumferential direction. The height of the wave increases as the amount of bending increases.

  And when the height of this wave becomes high and the part b that protrudes downward exceeds the height of the convex part 38a and comes into contact with the upper end surface in FIG. 4 of the ring 38 between the convex parts 38b, The undulation deformation of the spring 25 is limited by the ring 38, and when the amount of deflection of the plate spring 25 is increased at the point of contact, as shown by the broken line in FIG. The urging force has a non-linear characteristic with respect to the deflection amount.

  That is, when the leaf spring 25 is initially bent and only the convex portion 38a of the ring 38 is in contact with the leaf spring 25, the leaf spring 25 is bent to the maximum by causing the valve body 12 to make the maximum stroke. In the embodiment, when the valve body 12 is stroked until the valve body 12 is seated on the annular valve seat 21f of the partition member 21, the portion b that generates a wave that protrudes downward is abutted against the upper end surface in FIG. 4 of the ring 38 between the convex portions 38a. If the height of the convex portion 38a is set so as not to contact, the characteristic of the urging force with respect to the amount of deflection of the leaf spring 25 becomes a characteristic close to linear as shown by the solid line in FIG. That is, when the valve body 12 makes an arbitrary predetermined stroke less than the maximum stroke toward the leaf spring 25, a portion b that generates a wave that protrudes below the leaf spring 25 is a diagram of the ring 38 between the protrusions 38a. 4 Hit the top edge of the middle As described above, if the height of the convex portion 38a is set, the characteristic of the urging force with respect to the amount of bending of the leaf spring 25 becomes a characteristic close to linear until a predetermined stroke, and a broken line in FIG. As shown in FIG. That is, by setting the height of the convex portion 38a, it is possible to keep the urging force characteristic with respect to the deflection amount of the leaf spring 25 as a characteristic close to linear or to change from a characteristic close to linear to a non-linear characteristic. .

  Further, since the leaf spring 25 is in contact with the convex portion 38 a formed on the ring 38, the space formed by the leaf spring 25, the valve body 12, and the small diameter holding member 23 may be isolated from the pressure chamber 18. The pressure acting on the upper and lower surfaces of the leaf spring 25 is made equal.

  In turn, the valve body 14 disposed on the lower side in FIG. 1 of the leaf valve 10a on one side is configured similarly to the valve body 12 described above, and the inner diameter on the partition member 26 side is set to a large diameter. The valve body 14 includes a large diameter portion 14a formed and a small diameter portion 14b formed by setting the inner diameter of the counter partitioning member side to a small diameter. The valve body 14 has the large diameter portion 14a fixed to the piston rod 5. The piston 2 serving as a valve disk is slidably mounted on the outer periphery of a large-diameter holding member 27 that is immovable in the axial direction, and the small-diameter portion 14b is fixed to the piston rod 5 with respect to the piston 2 serving as a valve disk. By slidably mounting the outer periphery of the small-diameter holding member 28 that is immovable in the axial direction, the large-diameter holding member 27 and the small-diameter holding member 28 can move in the vertical direction in FIG. And the valve body 14 Defining a pressure chamber 19 on the other side between the holding members 27 and 28.

  Similarly to the large-diameter holding member 22 that holds the valve body 14 as described above, the large-diameter holding member 27 has an inner peripheral portion 27a that is annular and is fixed to the piston rod 5 and has a thick wall. And an annular groove 27b formed on the inner periphery and a passage 27c that opens from the inner periphery and leads to the end facing the pressure chamber 19 on the other side.

  The large-diameter holding member 27 is laminated on the partition member 26 and fixed to the tip 5a of the piston rod 5 so that the annular groove 27b is not movable in the axial direction with respect to the piston 1. 5, the pressure chamber 19 on the other side communicates with the communication passage 16, and the pressure chamber 19 has an inside of the one chamber 41. The pressure is guided.

  The outer diameter of the inner peripheral portion 27a of the large-diameter holding member 27 is set to a diameter that does not block the through hole 26e even when the outer peripheral portion 27a is stacked on the partition member 26, and the outer diameter is maintained by the thickness of the inner peripheral portion 27a. A gap is formed between the member 27 and the partition member 26 to communicate the other chamber 42 to the sub flow path 8b.

  On the other hand, the small-diameter holding member 28 is also annular like the small-diameter holding portion 23, and the inner peripheral side is fixed to the piston rod 5. The small-diameter holding member 28 and the large-diameter holding member 27 serve as a spacer 35 and a leaf spring. 29 and spacer 36 are sandwiched. In other words, the leaf spring 29 is housed in the pressure chamber 19 on the other side, and the outer periphery which is fixed on the inner peripheral side and which becomes the free end is bent. The leaf spring 29 is formed by laminating a plurality of annular plates, and the outer periphery of the leaf spring 29 is laminated on a step portion 14c formed at the boundary between the large diameter portion 14a and the small diameter portion 14b of the valve body 14. The valve body 14 is bent in contact with the convex portion 38 a and biases the valve body 14 in a direction away from the partition member 26.

  Furthermore, the spacer 34 is formed by laminating a plurality of annular plates having a smaller diameter than the leaf valve 10a. The number of the annular plates can be arbitrarily determined according to the thickness of the leaf valve 10a. It may be constituted only by a thick annular plate. Even in the spacers 35, 36, a plurality of annular plates having a smaller diameter than the leaf spring 29 are laminated, and the number of the annular plates laminated is arbitrary according to the thickness of the leaf spring 29. Alternatively, it may be composed of only one thick annular plate.

  Returning, the valve element 14 is urged downward in FIG. 1 by the leaf spring 29, and is arranged at the lowermost position in the figure regulated by the stopper 37 when no other force is applied. That is, the valve body 14 is disposed in the other chamber 42 and is urged upward by the pressure of the other chamber 42 which acts as the pressure receiving area of the lower surface of the small diameter portion 14b in FIG. 1, the pressure of the other chamber 42 acting as the pressure receiving area, the pressure of the pressure chamber 19 on the other side acting as the pressure receiving area of the stepped portion 14 c in FIG. 1, and the spring force of the leaf spring 29. It is energized downward. Therefore, the pressure of the other chamber 42 is urged upward with the area surrounded by the inner edge of the large-diameter portion 14a and the inner edge of the small-diameter portion 14b as a pressure-receiving area. The pressure urges the valve body 14 downward with the area surrounded by the inner edge of the large diameter portion 14a and the inner edge of the small diameter portion 14b as a pressure receiving area.

  The groove 14d provided on the lower surface of the small-diameter portion 14b of the valve body 14 guides the pressure in the other chamber 42 to the contact portion via the groove 14d even when the valve body 14 is in close contact with the stopper 37. The pressure in the other chamber 42 can be applied to the entire lower surface of the valve body 14 in FIG. Further, in the present embodiment, the lower limit of movement of the valve body 14 is determined using the stopper 37, but the diameter of the upper end of the piston nut 30 in FIG. You may make it perform the function as a stopper.

  The throttle valve 13 on the other side includes a valve body 14, a leaf spring 29, and an annular valve seat 26 f provided on the partition member 26, and the valve body 14 resists the urging force of the leaf spring 29. 1, the large-diameter portion 14a approaches the annular valve seat 26f provided on the partition member 26 so as to reduce the flow passage area in the sub flow passage 8b. When the upper end in FIG. 1 of the large-diameter portion 14a of the body 14 is seated on the annular valve seat 26f, the communication between the other chamber 42 and the room R2 by the sub-channel 8b is blocked, and the channel 8 on the other side The channel area is reduced to the channel area of the main channel 8a.

  In other words, as can be understood from the above description, the other side throttle valve 13 is different from the pressure in the other chamber 42 and the pressure in the one chamber 41 only in the direction of application to the valve body 14, and the one side throttle valve 11 described above. When the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the valve element 14 moves upward in FIG. The operation is performed so as to reduce the flow path area of the side flow path 8. When the valve body 14 is moved upward in FIG. 1 and approaches the partition member 26, the flow passage area of the other flow passage 8 is reduced by narrowing the flow passage area of the sub flow passage 8b leading to the through hole 26e. Eventually, the sub-channel 8b is shut off, and only the main channel 8a communicates the other chamber 42 and the upstream side of the other port 2b.

  Even in the throttle valve 13 on the other side, a single flow path may be throttled by the throttle valve 13 on the other side without branching the flow path 8 on the other side. The sub flow path 8b starts to be throttled, but the predetermined amount can be arbitrarily set by the cross-sectional area of the stepped portion 14c and the spring constant of the leaf spring 29 in the same manner as the throttle valve 11 on one side. The piston speed of the shock absorber is set at the boundary between medium speed and high speed.

  Further, the advantage of using the leaf spring 29 is the same as that of the throttle valve 11 on one side, but the one chamber serving as a reference for the throttle valve 11 on one side to start to throttle the flow path 7 on the one side during the expansion stroke of the shock absorber. The pressure in the other chamber 42, which is a reference for the pressure of the other chamber 42 to exceed the pressure in the other chamber 42, and the reference for the throttle valve 13 on the other side to begin to throttle the channel 8 on the other side during the compression stroke of the shock absorber 41 The predetermined amount that should exceed the pressure may be different.

  In addition, a ring 38 provided with convex portions 38a at three locations is also provided on the stepped portion 14c of the valve body 14 in the throttle valve 13 on the other side, and a leaf spring 29 is brought into contact with the convex portion 38a to provide a valve. Since the body 14 is energized, the total valve length of the shock absorber can be shortened, and the problem that the stroke length of the shock absorber is shortened can be eliminated, so that the stroke amount of the valve body 14 can be secured. It has become. Since the leaf spring 29 is in contact with the convex portion 38 a of the ring 38, the space formed by the leaf spring 29, the valve body 14 and the small diameter holding member 28 is not isolated from the pressure chamber 19. Thus, the pressure acting on the upper and lower surfaces of the leaf spring 29 becomes equal.

  Further, in the configuration of the throttle valves 11 and 13, the valve bodies 12 and 14 are cylindrical and are attached to the holding members 22, 23, 27 and 28, respectively. 23, 27 and 28 are guided to ensure good operation and the pressure chambers 18 and 19 can be easily formed, and the valve can be easily assembled. Naturally, the design can be changed so as to be suitable for the flow path 7 on one side and the flow path 8 on the other side.

  Further, since the communication passage 15 only needs to connect the pressure chamber 18 on one side to the other chamber 42, the communication hole 15 may be configured by the vertical hole 15a and the through hole 15c without the horizontal hole 15b.

  Next, the operation of the valve structure configured as described above will be described. First, when the shock absorber is in the extension stroke and the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the pressure in the one chamber 41 increases, and the hydraulic oil in the one chamber 41 causes the port 2a on one side to flow. Passing through and trying to move into the other chamber 42.

  When the piston speed, which is the expansion / contraction speed of the shock absorber, is in the low speed region, the hydraulic oil is formed by stamping the notch provided on the outer periphery of the leaf valve 10a seated on the valve seat 1a or the valve seat 1a. When passing through the orifice and the piston speed thereafter increases to reach the middle speed region, the hydraulic oil deflects the outer periphery of the leaf valve 10a so that it also passes through the gap between the leaf valve 10a and the valve seat 1a. become.

  When the piston speed is in the low / medium speed region, the predetermined amount is set so that the pressure in the one chamber 41 does not exceed the pressure in the other chamber 42 by a predetermined amount. 1, the valve body 12 cannot move downward in FIG. 1 against the urging force of the leaf spring 25, and the throttle valve 11 on one side throttles the flow path 7 on the one side to flow area. Will not be reduced.

  Therefore, when the piston speed is in the low / medium speed region, the damping characteristic (relationship of the damping force with respect to the piston speed) by the leaf valve 10a on one side is exhibited. Then, by setting the rigidity of the leaf valve 10a low, as shown by the solid line in FIG. 8, the piston speed is set so that the slope of the damping characteristic in the medium speed region is small and the generated damping force is low. Can do.

  On the other hand, the speed of the piston 1 reaches the high speed region, and the difference between the pressure in the one chamber 41 and the pressure in the other chamber 42 increases, and the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount. Then, the thrust that presses the valve element 12 downward in FIG. 1 due to the differential pressure between the one chamber 41 and the other chamber 42 exceeds the force of the leaf spring 25, and the valve element 12 is pushed downward in FIG. Thus, the sub flow path 7b is narrowed to reduce the flow area of the flow path 7 on one side.

  When the difference between the pressure in the one chamber 41 and the pressure in the other chamber 42 further increases after the piston speed reaches the high speed region, the valve body 12 gradually increases the flow path area according to the pressure difference. Gradually decreasing, and finally abutting the annular valve seat 21f of the partition member 21 to cut off the communication between the one chamber 41 and the port 2a through the through hole 21e, the sub flow path 7b is closed, and the main flow path 7a Only the one chamber 41 and the port 2a are communicated with each other to minimize the channel area of the channel 7 on one side.

  Therefore, when the speed of the piston 1 is in the high speed region, the flow path area of the flow path 7 on one side is gradually reduced as the difference between the pressure in the one chamber 41 and the pressure in the other chamber 42 increases. As the speed increases, the pressure loss gradually increases.

  That is, as shown in the solid line in FIG. 8, the channel area is gradually limited when the piston speed reaches the high speed region and the throttle valve 11 on the one side stops the throttle for the first time. Therefore, the inclination becomes larger than that in the middle speed region, and the damping force increases as the speed of the piston 1 increases. For the increase in piston speed after the throttle valve 11 on one side minimizes the flow area of the flow path 7 on the one side, the slope of the damping characteristic decreases again, but the flow area decreases. The damping force becomes high.

  Here, when the leaf spring 25 contacts the valve body 12 over the entire circumference, the spring constant of the leaf spring 25 becomes a non-linear characteristic, and the valve body 12 is greatly urged even with a small amount of deflection. Since the degree to which the flow path area of the flow path 7 of the valve body 12 is decreased is small, as shown in the alternate long and short dash line in FIG. 8, even when the piston speed reaches the high speed range, the slope of the damping coefficient is difficult to increase. However, in the valve structure of the present invention, since the leaf spring 25 is partially in contact with the valve body 12 in the circumferential direction, as described above, when the piston speed reaches the high speed region, the flow path 7 Therefore, the slope of the attenuation coefficient can be increased by gradually reducing the flow path area. In other words, since the biasing force of the leaf spring 25 can be made to have a characteristic close to linear with respect to the amount of deflection, the inclination of the damping coefficient when the piston speed is in the high speed range can be easily changed by setting the number of leaf springs 25. It is possible to tune. Further, when the height of the convex portion 12e is set so that the characteristic of the urging force of the leaf spring 25 changes from a characteristic close to linear to a non-linear characteristic before the valve body 12 reaches the maximum stroke, the damping characteristic is shown. As indicated by the broken line in FIG. 8, the slope of the attenuation coefficient, which was large in the range of characteristics close to linear, can be set to decrease from the middle, and the degree of freedom in tuning the attenuation characteristics can be improved.

  On the contrary, when the shock absorber is in the compression stroke and the piston 1 moves downward in FIG. 1 with respect to the cylinder 40, the hydraulic oil in the other chamber 42 passes through the port 2b on the other side and passes through the one chamber. In order to move into the flow 41, a resistance is given to the flow of the hydraulic oil by the leaf valve 10b on the other side to generate a damping force. When the shock absorber is in the compression stroke, the other throttle valve 13 arranged on the lower side of the piston 1 is operated, but the configuration is arranged on the one side arranged on the upper side of the piston 1. Since it is the same as the throttle valve 11, when the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the flow path 8 on the other side is reduced, and the pressure in the other chamber 42 and the pressure in the one chamber 41 are reduced. As the pressure difference increases, the flow path area of the flow path 8 on the other side is gradually reduced, and finally the other chamber 42 and the port 2b formed by the through hole 26e are brought into contact with the annular valve seat 26f of the partition member 26. The sub-flow path 7b is closed and the other flow path 42 and the port 2b are connected only by the main flow path 7a to minimize the flow area of the flow path 8 on the other side.

  That is, when the shock absorber is in the compression stroke, as in the case of the shock absorber being in the expansion stroke, as shown in FIG. 8, when the piston speed is in the low / medium speed region, the damping by the leaf valve 10b on the other side is performed. When the piston speed reaches the high speed region, the inclination becomes larger than when it is in the medium speed region, and the damping force increases as the speed of the piston 1 increases.

  As described above, in the valve structure of the shock absorber according to the present embodiment, when the piston speed is in the medium speed region, the piston speed is reduced when the piston speed reaches the high speed region while keeping the damping force low. The damping force can be made larger than when it is in the middle speed range, and even when the piston speed reaches the high speed range, the damping force will not be insufficient, vibration will be sufficiently suppressed, and the ride comfort in the vehicle Can be improved.

  In addition, in a situation where the amplitude at which the shock absorber is fully extended is large and the piston speed reaches the high speed region, the damping force generated by the shock absorber can be increased. It is possible to reduce the impact at the time of maximum extension.

  In addition, since the configuration in which the rear surfaces of the leaf valves 10a and 10b are urged by coil springs or the like is not employed, the variation in the damping characteristics of each product occurs due to variations in the urging force that urges the rear surfaces of the leaf valves 10a and 10b. This improves the reliability and stability of the valve structure of the shock absorber.

  And in this valve structure, since the leaf | plate spring 25 (29) is used for the spring which urges | biases the valve body 12 (14), the full length of a valve can be shortened and it is easy to ensure the stroke length of a buffer. It becomes.

  Further, a leaf spring 25 (29) is used as a spring for urging the valve body 12 (14), and the leaf spring 25 (29) is partially brought into contact with the valve body 12 (14) in the circumferential direction. The flow passage areas of the flow passages 7 and 8 can be gradually reduced according to the piston speed, and as shown in FIG. 8, the damping force increases with the increase of the piston speed when the piston speed is in the high speed region. The damping force does not change abruptly, and the vehicle occupant does not feel uncomfortable due to a sudden change in damping force or does not feel a shock. Since the generation of abnormal noise can be suppressed, riding comfort can be further improved.

  Further, a leaf spring 25 (29) is used as a spring for urging the valve body 12 (14), and the leaf spring 25 (29) is partially brought into contact with the valve body 12 (14) in the circumferential direction. Therefore, the variation of the spring constant for each product can be reduced, and a stable damping force can be generated in the shock absorber.

  Further, the main flow paths 7a and 8a and the sub flow paths 7b and 8b can be formed upstream of the ports 2a and 2b by simply stacking the partition members 21 and 26 on the piston 1 that is a valve disk. , 8a and sub-channels 7b, 8b can be easily formed, and the valve structure can be easily assembled.

  In addition, in the place mentioned above, the part which opposes the leaf | plate spring 25 (29) of the valve body 12 (14), the ring 38 provided with the convex part 38a in the step part 12c (14c) in the one embodiment mentioned above is laminated | stacked. Then, the leaf spring 25 is indirectly brought into partial contact with the valve body 12 (14) via the ring 38. However, as shown in FIG. 9, the leaf spring 25 protrudes from the step 12c (14c) where the ring 38 is eliminated. The portion 12e (14e) may be formed, and the convex portion 12e (14e) may be brought into contact with the leaf spring 25 (29). Also in this case, since the leaf spring 25 (29) partially abuts on the valve body 12 (14), the above-described effects can be obtained.

  Further, in the above description, the leaf spring 25 (29) of the valve body 12 (14) is used when the leaf spring 25 (29) is partially brought into contact with the valve body 12 (14) at intervals in the circumferential direction. Instead of this, the ring 38 is used instead of the convex portion 12e (14e) or the ring 38, but instead of this, as shown in FIG. 10, a leaf spring 39 provided with three notches 39a on the outer periphery is provided. You may make it contact | abut to the step part 12c (14c) of the valve body 12 (14) which eliminated 12e (14e).

  Also in this case, even if the valve body 12 (14) is stroked in the direction in which the leaf spring 39 is bent, the outer periphery of the leaf spring 39 is only pressed at a portion other than the notch 39a, and the undulation in the circumferential direction. Even if the deformation occurs, the corrugated deformation is not easily restricted by the valve body 12 (14).

  As described above, the undulation deformation in the circumferential direction of the leaf spring 39 is less likely to be restricted by the valve body 12 (14). 14), and the urging force acting on the valve body 12 (14) is predominantly due to the bending of the outer periphery of the leaf spring 39. The urging force of the leaf spring 39 is the same as that of the embodiment. Similar to the force structure, as shown by the solid line in FIG. 5, the characteristic is substantially proportional to the amount of deflection of the outer periphery, and the internal stress is also reduced, so that the amount of deflection of the valve body 12 (14) is secured. It will be. That is, in this case, the same operational effects as those of the above-described embodiment can be obtained.

  Furthermore, in the valve structure of the shock absorber in the above-described embodiment, the pressure in the other chamber 42 is guided to one pressure chamber 18 by being provided in the communication passages 15 and 16 of the piston rod 5, and the other pressure chamber 19. As shown in FIG. 11, the piston rod 5 is provided with only a single communication passage 43 that communicates the one chamber 41 and the other chamber 42, and this communication passage is provided. At least one or more orifices 44, 45 may be provided at both ends of 43, and the pressure between the orifice 44 and the orifice 45 may be guided to the respective pressure chambers 18, 19. The pressure between the orifices 44 and 45 in the communication passage 43 becomes an intermediate pressure that falls within the range between the pressure in the one chamber 41 and the pressure in the other chamber 42 due to the pressure loss of the orifices 44 and 45. , 45 are arbitrarily set. Two orifices 44 (45) are provided, but one orifice 44 may be provided, and the orifice 44 depends on how the intermediate pressure is set with respect to the pressure in the one chamber 41 and the other chamber 42. The number of (45) may be determined, and the resistance given to the flow in the orifice 44 (45) may be determined depending on the setting of the intermediate pressure.

  Also in this case, when the shock absorber is in the extension stroke, the pressure of the one chamber 41 acts on the valve body 12 of one throttle valve 11 in the closing direction and the intermediate pressure lower than the pressure of the one chamber 41 in the opening direction. Therefore, when the piston speed is increased, the valve body 12 can be moved closer to the partition member 22 to reduce the flow path area of the flow path 7. On the contrary, when the shock absorber is in the compression stroke, the other throttle valve 13 is operated. Since the pressure of the other chamber 42 acts in the closing direction and the intermediate pressure lower than the pressure of the other chamber 42 acts in the opening direction, the valve body 14 approaches the partition member 26 when the piston speed increases. At least, the flow channel area of the flow channel 8 can be reduced, and the operation similar to that of the shock absorber according to the above-described embodiment is exhibited, and the same effect is obtained.

  Subsequently, a valve structure in a modification of the other embodiment shown in FIG. 12 will be described.

  The valve structure in this modified example is different in the shape of the valve body in the throttle valve 11 on one side and the throttle valve 13 on the other side, and the other configuration is the same as the valve structure of the embodiment. Different points will be described, and the same members will be denoted by the same reference numerals and description thereof will be omitted.

  The valve structure in the other embodiment is different from the valve structure in the one embodiment, specifically, as shown in FIG. 12, the valve body in the throttle valve 11 on one side and the throttle valve 13 on the other side. 51 and 52 are formed in a cylindrical shape, with large diameter portions 51a and 52a formed by setting the inner diameter on the partition member 21 and 26 side to a large diameter and the inner diameter on the side opposite to the partition member set to a small diameter. Spring support portions 51c, 52c formed by setting the inner diameters of the small diameter portions 51b, 52b and the intermediate portions between the large diameter portions 51a, 52a and the small diameter portions 51b, 52b to be smaller than the small diameter portions 51b, 52b. These valve bodies 51 and 52 have large-diameter holdings in which the large-diameter portions 51a and 52a are fixed to the piston rod 5 and are immovable in the axial direction with respect to the piston 2 which is a valve disk. Slide on the outer periphery of members 22 and 27 The small diameter portions 51b and 52b are slidably mounted on the outer periphery of the small diameter holding members 23 and 28 fixed to the piston rod 5 and fixed in the axial direction with respect to the piston 2 which is a valve disk. The large-diameter holding members 22 and 27 and the small-diameter holding members 23 and 28 are movable in the vertical direction in FIG. 12, which is the axial direction, and the valve body 51 is interposed between the holding members 22 and 23. A pressure chamber 18 on one side is defined, and the valve body 52 defines a pressure chamber 19 on the other side between the holding members 27 and 28.

  Even in this embodiment, the leaf springs 25 are equidistant in the circumferential direction at three locations of the ring 38 whose outer periphery is stacked on the lower end in FIG. 12 of the spring support 51c of the valve body 51. The valve body 51 is biased in a direction away from the partition member 21 by the leaf spring 25, and the other leaf spring 29 is also spring-supported by the valve body 52. The portion 52c is bent in contact with the convex portions 38a provided at equal intervals in the circumferential direction at three locations of the ring 38 stacked on the upper end in FIG. 12, and the valve body 52 is bent by the leaf spring 29. It is energized in the direction away from.

  That is, even in this embodiment, the ring 38 forms a part of the valve body 51 (52), and the leaf spring 25 (29) surrounds the valve body 51 (52) via the ring 38. The valve body 51 (52) is urged by partially abutting in the direction.

  And in this valve body 51, the internal diameter in the spring support part 51c between the large diameter part 51a and the small diameter part 51b is set to the minimum diameter, and the upper end in FIG. 12 of the said spring support part 51c is small diameter. Since the further upward movement of the valve body 51 is restricted by contacting the lower end in FIG. 12 of the holding member 23, the stopper 24 is eliminated in the valve structure in this modified example. A groove 51d is formed at the upper end of the spring support portion 51c in FIG. 12, and even if the upper end of the spring support portion 51c in FIG. 12 is in close contact with the small-diameter holding member 23, the contact portion is interposed through the groove 51d. The pressure in the pressure chamber 18 on one side can be guided to apply the pressure in the pressure chamber 18 to the entire upper surface of the spring support 51c in FIG.

  Similarly, in the valve body 52, the lower end of the spring support portion 52c in FIG. 10 contacts the upper end of the small diameter holding member 28 in FIG. In the valve structure in this modified example, the stopper 37 is eliminated. A groove 52d is formed at the lower end in FIG. 10 of the spring support portion 52c, and even if the lower end in FIG. 10 of the spring support portion 52c is in close contact with the small diameter holding member 28, the contact portion is interposed through the groove 52d. Thus, the pressure in the pressure chamber 19 on the other side can be guided to apply the pressure in the pressure chamber 19 to the entire lower surface of the spring support 52c in FIG.

  Even in the valve structure according to the modified example configured as described above, the pressure of the one chamber 41 (the other chamber 42) and the pressure chamber 18 facing the pressure are similar to the valve body 12 (14) of the embodiment. The pressure of (19) acts on the pressure receiving area surrounded by the inner edges of the large diameter portions 51a and 52a and the inner edges of the small diameter portions 52a and 52a, and when the piston speed becomes a high speed region, the leaf spring 25 (29) As the valve body 51 (52) approaches the annular valve seat 21f (26f) and restricts the flow path 7 (8), the shock absorber generates a damping force as shown in FIG. Like the valve structure of the embodiment, the above-described various functions and effects can be achieved.

  Further, since the valve body 51 (52) is provided with the spring support portion 51c (52c) that receives the urging force of the leaf spring 25 (29), the one chamber 41 does not depend on the diameter of the leaf spring 25 (29). The area surrounded by the inner edge of the large-diameter portion 51a, 52a and the inner edge of the small-diameter portion 52a, 52a on which the pressure of the (other chamber 42) and the pressure of the pressure chamber 18 (19) opposite to the pressure acts, ie, the pressure receiving area Can be set. Therefore, the pressure receiving area can be set smaller than that of the valve structure of the embodiment, and even if the spring constant of the leaf spring 25 (29) is set to be small, the above-described valve structure of the embodiment of the valve structure can be achieved. The valve according to the embodiment can secure the stroke length of the shock absorber by reducing the total axial length of the piston portion by reducing the thickness of the leaf spring 25 (29). It becomes even easier compared to the structure.

  In the present embodiment, in order to explain the change of the damping characteristic, the piston speed is provided with sections of low speed, medium speed, and high speed, but the speed of the boundary between these sections is arbitrarily set. be able to.

  Further, in the above description, the valve structure of the present invention has been described using an example embodied in the damping valve on both sides of the pressure expansion of the piston portion of the shock absorber, but the damping valve only on the expansion side or only on the pressure side Further, in the case where the shock absorber is set to a double-tube shock absorber provided with a reservoir outside the cylinder and includes a base valve, the valve structure of the present invention is used as the base valve portion. Needless to say, the present invention can be applied to a valve of a shock absorber that functions as a damping force generating element that generates a damping force. That is, when the valve structure is embodied in the base valve portion, one chamber may be one of the piston side chamber or the reservoir chamber, and the other chamber may be the other of the piston side chamber or the reservoir chamber. Furthermore, the valve structure can be embodied in both the piston part and the bale valve part of the shock absorber.

 This is the end of the description of the embodiment of the valve structure of the shock absorber, but the scope of the present invention is not limited to the details shown or described.

It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in one embodiment was embodied. It is a model figure which shows the deformation | transformation state of a leaf | plate spring. It is the figure which showed the characteristic of the amount of bending, and energizing force at the time of energizing making the whole circumference of a leaf spring contact a valve element. It is the figure which showed the state which the leaf | plate spring with which the valve | bulb structure of the shock absorber in one Embodiment was embodied bent and energized the valve body. It is the figure which showed the deflection amount of the leaf | plate spring with which the valve | bulb structure of the shock absorber in one Embodiment was implemented, and the characteristic of urging | biasing force. It is the figure which showed the result of having analyzed the urging | biasing force with respect to the deflection amount of the leaf | plate spring provided with the convex part from which a circumferential direction width differs. It is the figure which showed the result of having analyzed the maximum value of the internal stress in a leaf | plate spring with respect to the bending amount of the leaf | plate spring provided with the convex part from which a circumferential direction width differs. It is a figure which shows the damping characteristic in the buffer which embodied the valve | bulb structure of the buffer of one Embodiment. It is a longitudinal cross-sectional view of the piston part of the shock absorber by which the valve structure in one modification of one embodiment was embodied. It is a top view of the leaf | plate spring with which the valve structure in the other modification of one Embodiment was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in another modification of one embodiment was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in other embodiments was embodied. It is a longitudinal cross-sectional view of the piston part of the buffer which actualized the valve structure of the conventional buffer. It is a figure which shows the damping characteristic in the buffer which actualized the valve structure of the conventional buffer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piston 1a, 1b which is a valve disc Valve seat 2a One side port 2b Other side port 3a, 3b Window 5 Piston rod 5a Piston rod tip 5b Piston rod step part 5c Piston rod screw groove 7 One side flow path 7a, 8a Main flow path 7b, 8b Sub flow path 8 Flow path 10a on the other side Leaf valve 10b on the other side Leaf valve 11 on the other side Throttle valves 12, 14, 51, 52 Valve bodies 12a, 14a, 51a , 52a Large diameter portions 12b, 14b, 51b, 52b in the valve body Small diameter portions 12c, 14c in the valve body Step portions 12d, 14d, 51d, 52d in the valve body Grooves 12e, 14e in the valve body 13 Convex portion 13 in the valve body The other side Throttle valves 15, 16, 43 Communication passages 15a, 16a Vertical holes 15b, 16b Horizontal holes 15c, 16c Through holes 17a, 17 Plugs 18, 19 Pressure chambers 21, 26 Partition members 21a, 26a Bottom portions 21b, 26b in partition members Tube portions 21c, 26c in partition members Holes 21d, 21e, 26d, 26e Through holes 21f, 26f in partition members Partition members Annular valve seats 22 and 27 Large diameter holding members 22a and 27a Inner peripheral portions 22b and 27b in the large diameter holding members Annular grooves 22c and 27c in the large diameter holding members Paths 23 and 28 in the large diameter holding members Small diameter holding members 24 and 37 Stopper 25, 29, 39 Leaf spring 25a, 29a Notch 30 in leaf spring Piston nut 31, 32, 33, 34, 35, 36 Spacer 38 Ring 38a that forms part of valve body 38a Convex part 38b Ring edge 39a Notch 40 in leaf spring Cylinder 41 One chamber 42 Other chamber 44 45 orifices 51c, the spring support portion R1 in 52c the valve body, R2 room

Claims (12)

A valve disc having a port separating the one chamber and the other chamber in the shock absorber and communicating with the one chamber and the other chamber, and a leaf valve stacked on the side of the other chamber of the valve disc to open and close the port And a throttle valve provided with a valve body provided in the middle of the flow path and capable of reducing the flow path area. The pressure of the one chamber is applied to the valve body so as to give a thrust in the direction of reducing the flow path area, and the pressure of the other chamber or the pressure of the one chamber and the pressure of the other chamber is given to the thrust opposite to the thrust by the pressure of the one chamber. An intermediate pressure is applied, and a leaf spring is provided to urge the valve body in a direction opposite to the thrust due to the pressure in the one chamber, and the leaf spring is partially abutted against the valve body in the circumferential direction. It is characterized by Valve structure of 衝器. A valve disk having one side port and the other side port for separating the one chamber and the other chamber and separating the one chamber and the other chamber in the shock absorber, and laminated on the side surface of the other chamber of the valve disk In the valve structure of the shock absorber, comprising a leaf valve on one side that opens and closes a port on one side, and a leaf valve on the other side that opens and closes the port on the other side stacked on one side of the valve disk. Provided in the middle of the one-side flow path that communicates the one chamber and the upstream of the one-side port, the other-side flow path that communicates the other chamber and the upstream of the other-side port, and the one-side flow path. One side throttle valve with a valve body capable of reducing the flow path area and the other side throttle valve with a valve body provided in the middle of the other side flow path and capable of reducing the flow path area In the direction of reducing the flow area to the valve body on one side. The pressure of the one chamber is applied so that the thrust of the one chamber is applied to the valve body on one side, and the pressure of the other chamber or the intermediate pressure between the pressure of the one chamber and the pressure of the other chamber is applied The pressure in the other chamber is applied to the other valve body so as to give a thrust in the direction of reducing the flow passage area, and the pressure in the one chamber or the other valve body is given a thrust opposite to the thrust due to the pressure in the other chamber. An intermediate pressure between the pressure in one chamber and the pressure in the other chamber is applied, and the leaf spring on one side that urges the valve body on one side in a direction opposite to the thrust due to the pressure on the one chamber, and the valve body on the other side A shock absorber valve characterized by comprising a leaf spring on the other side biased in a direction opposite to a thrust due to a chamber pressure, and the leaf spring partially contacting the valve body at an interval in the circumferential direction Construction. The buffer according to claim 1, further comprising a convex portion formed at two or more locations on the circumference of the end portion facing the leaf spring of the valve body, wherein the convex portion is brought into contact with the leaf spring. Valve structure. 4. The shock absorber valve structure according to claim 3, wherein the convex portions are provided at equal intervals on the periphery of the valve body and the inner peripheral edge is disposed on the same circumference. 5. The shock absorber according to claim 3, wherein when the valve body makes a predetermined stroke toward the leaf spring, a portion that protrudes under the wave-deformed leaf spring abuts between the convex portions of the valve body. Valve structure. The valve structure for a shock absorber according to claim 1 or 2, wherein notches are provided at two or more locations on the outer periphery of the leaf spring, and a portion other than the notch of the leaf spring is brought into contact with the valve body. 7. The shock absorber valve structure according to claim 6, wherein the notches are provided at equal intervals on the outer periphery of the leaf spring. A pressure chamber for energizing the valve body of the throttle valve in a direction in which a pressure lower than that of the one chamber is introduced and the flow passage area is not reduced by the pressure is provided, and a leaf spring is accommodated in the pressure chamber. The valve structure of the shock absorber according to any one of 1 to 7. 9. The shock absorber valve structure according to claim 1, wherein the flow path includes a main flow path and a sub flow path, and the throttle valve reduces the flow path area by closing the sub flow path. . A partition member that forms a chamber that is stacked on the valve disk and communicates with the main flow path and the sub flow path is provided upstream of the port, and the flow area of the sub flow path is reduced by the valve body approaching the partition member. The shock absorber valve structure according to claim 9. The valve body has a cylindrical shape, and includes a large diameter portion formed by setting the partition member side inner diameter to a large diameter and a small diameter portion formed by setting the counter partition member side inner diameter to a small diameter. In contrast, a large-diameter holding member and a small-diameter holding member that are immovable in the axial direction are provided, and the large-diameter portion of the valve body is slidably mounted on the outer periphery of the large-diameter holding member, and the small-diameter portion of the valve body is small-diameter holding member A pressure chamber is defined between the valve body and each holding member so as to be slidably mounted on the outer periphery of the valve body. The shock absorber valve structure according to claim 10, wherein the valve body is urged in a direction away from the partition member by abutting against a step portion at the boundary. The valve body has a cylindrical shape, a large diameter portion formed by setting the partition member side inner diameter to a large diameter, a small diameter portion formed by setting the counter partition member side inner diameter to a small diameter, and a large diameter portion A large-diameter holding member and a small-diameter holding member that are fixed in the axial direction with respect to the valve disk. A member is provided, and the large-diameter portion of the valve body is slidably mounted on the outer periphery of the large-diameter holding member, and the small-diameter portion of the valve body is slidably mounted on the outer periphery of the small-diameter holding member. A pressure chamber is defined between the plate member, the leaf spring is annular, and the outer periphery which is a free end is brought into contact with the spring support portion of the valve body to urge the valve body in a direction away from the partition member. The shock absorber valve structure according to claim 10.

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