Damping valve and shock absorber

Abstract

This damping valve (1) is provided with: a valve seat member (2) which is provided with an annular recess (2d), a port (2c) that opens at the bottom (2d1) of the recess (2d), and an annular valve seat (2e) that rises from the outer periphery of the recess (2d), and which has an annular facing section (2f) that faces the inner peripheral surface of the recess (2d); an annular sub-valve (3) which is disposed inside the recess (2d) and away from the bottom (2d1) of the recess (2d), forms an annular gap (P) between the outer peripheral surface of the sub-valve (3) and the facing portion (2f), and is bendable inside the recess (2d) in a direction away from the valve seat member (2) as a free end on the outer peripheral side thereof, the sub-valve (3) being disposed inside the recess (2d) and away from the bottom (2d1) of the recess (2d); and an annular leaf valve (4) which is stacked on the side of the sub-valve (3) opposite to the valve seat member so as to be separated from the axial direction, and which can be seated away from the valve seat (2e) while being bendable on the outer peripheral side as a free end.

Description

Technical Field

[0001] The invention relates to a damping valve and a buffer. Background Art

[0002] In the past, damping valves were generally used to generate damping force by applying resistance to the flow of liquid generated during the expansion and contraction of the buffer. In addition, as shown in Japanese patent JP2019-183918A, such a damping valve includes: an annular valve body whose inner periphery is fixed to the piston rod and is allowed to bend axially on both sides of the outer periphery; a cup-shaped valve housing having an annular relative setting portion that forms a gap relative to the outer periphery of the annular valve body to allow liquid to pass; a gasket that supports the inner periphery of the annular valve body; and a valve stopper that limits the bending of the annular valve seat.

[0003] According to the damping valve constructed in this manner, in a speed range where the expansion and contraction speed (piston speed) of the buffer is low and the annular valve body does not bend, the gap between the outer periphery of the annular valve body and the annular opposing portion of the valve housing can be maintained in a relatively narrow state. On the other hand, if the piston speed of the buffer increases and the outer periphery of the annular valve body bends, the outer periphery end of the annular valve body moves away from the annular opposing portion, and thus the gap widens.

[0004] Therefore, in the buffer that utilizes the damping valve to generate damping force, in the micro-slow speed range where the extension and retraction speed is lower than the low speed, the damping coefficient is increased so that the damping force increases rapidly in proportion to the extension and retraction speed, while in the low speed range, the damping coefficient can be reduced to below the micro-slow speed range, thereby achieving a damping force characteristic that is more conducive to improving the ride comfort of the vehicle. Prior art literature Patent Literature

[0005] Patent Document 1: JP2019-183918A Summary of the invention Problems to be solved by the invention

[0006] The conventional damping valve is used to generate damping force when the buffer is extended and retracted in a micro-low speed range, and is arranged in series with the leaf valve, and the leaf valve is used to generate damping force when the buffer is extended and retracted at a speed greater than or equal to the low speed.

[0007] Specifically, the damping valve faces a piston that divides the inside of the shock absorber's cylinder into an extension side chamber and a compression side chamber, and is stacked with a laminated leaf valve that can open or close a port provided on the piston and mounted on the outer periphery of the piston rod.

[0008] Therefore, such a damping valve is arranged opposite to the piston and the leaf valve and is stacked in the buffer. Since the piston part includes the piston, the leaf valve and the damping valve, its total length becomes longer, so there is a problem that the stroke length of the buffer becomes shorter.

[0009] In addition, in order to manufacture buffers with different cylinder diameters, it is necessary to prepare multiple valve housings corresponding to the cylinder diameters, which makes parts management very troublesome and increases manufacturing costs.

[0010] Furthermore, since the damping valve is composed of a plurality of components including a gasket and a valve stopper in addition to the annular valve body and the valve housing, the damping valve has poor assemblability and is very time-consuming to assemble.

[0011] Therefore, an object of the present invention is to provide a damping valve and a shock absorber which can shorten the total length, are inexpensive, and have good assemblability. Solutions to Solve Problems

[0012] In order to solve the above-mentioned problems, the damping valve of the present invention comprises: a valve seat component, which comprises an annular recess, a port opening at the bottom of the recess, an annular valve seat rising from the outer periphery of the recess, and a relatively set portion which is annular and has an inner peripheral surface facing the recess; an auxiliary valve, which is configured in the recess and away from the bottom of the recess, is annular and forms an annular gap between the outer peripheral surface and the relatively set portion, and the outer peripheral side can be bent as a free end in the recess in a direction away from the valve seat component; a leaf valve, which is annular and is stacked away from the axial direction on the side of the auxiliary valve opposite to the valve seat component, and the outer peripheral side can be bent as a free end so as to be able to be seated relative to the valve seat.

[0013] In the damping valve constructed in this manner, since the valve seat member having the valve seat on which the leaf valve can be seated is provided with a recessed portion that can accommodate the auxiliary valve and allow the auxiliary valve to bend and a relative setting portion that is opposite to the outer periphery of the auxiliary valve, the valve seat member can be used as a valve seat for both the auxiliary valve and the leaf valve. In this way, according to the damping valve, the valve seats for both the auxiliary valve and the leaf valve can be concentrated on one valve seat member, the number of components can be reduced, and the total length can be shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a longitudinal cross-sectional view of a shock absorber including a damping valve according to an embodiment of the present invention. Figure 2 It is a cross-sectional view of a damping valve according to an embodiment of the present invention. Figure 3 This is a partially enlarged view of a damping valve according to an embodiment of the present invention. Figure 4 This is a damping force characteristic diagram of a shock absorber including a damping valve according to an embodiment of the present invention. Figure 5 It is a cross-sectional view of a damping valve according to a first modified example of one embodiment of the present invention. Figure 6It is a cross-sectional view of a damping valve according to a second modified example of the one embodiment of the present invention. DETAILED DESCRIPTION

[0015] The present invention will be described below based on the embodiments shown in the drawings. Figure 1 and Figure 2 As shown, the damping valve 1 of the present embodiment includes a valve housing 2 as a valve seat member, a sub-valve 3, and a leaf valve 4, and is disposed in a telescopic damper body 10 having a housing 14 and a rod 12 movably inserted into the housing 14, and is used as a bottom valve of a damper D. Furthermore, the damper D can be sandwiched between a vehicle body and an axle of a vehicle (not shown) when in use, to suppress vibrations of the vehicle body and wheels.

[0016] The following will describe in detail the various parts of the damping valve 1 and the buffer D. Figure 1 As shown, the buffer body 10 comprises: a cylinder 11, a bottomed cylindrical shell 14 covering the outer circumference of the cylinder 11, a rod 12 in the shell 14 and movably inserted into the cylinder 11, and a piston 13, wherein the piston is connected to the rod 12 and is movably inserted into the cylinder 11 and divides the interior of the cylinder 11 into an extension side chamber R1 and a compression side chamber R2 as a working chamber.

[0017] Furthermore, at the rod 12 Figure 1 A bracket (not shown) is provided on the base end shown as the upper end in the figure, and the rod 12 is connected to one of the vehicle body and the axle via the bracket (not shown). In addition, a bracket (not shown) is also provided on the bottom 14a of the housing 14, and the housing 14 is connected to the other of the vehicle body and the axle via the bracket (not shown).

[0018] In this way, the buffer body 10 of the buffer D is sandwiched between the vehicle body and the axle. When the vehicle travels on an uneven road, the wheel vibrates up and down relative to the vehicle body, the rod 12 moves in and out of the housing 14, and the piston 13 moves up and down (axially) in the cylinder 11.

[0019] The shock absorber body 10 is provided with an annular guide 15 that blocks the upper ends of the cylinder 11 and the housing 14 and into which the rod 12 can be slidably inserted. Therefore, the cylinder 11 and the housing 14 form a sealed space.

[0020] Furthermore, a valve housing 2 serving as a valve seat member is fitted to the lower end of the cylinder 11. Figure 1 The upper end of the middle portion is bent inward from the outer peripheral side by riveting, and together with the bottom portion 14 a , holds the guide 15 , the cylinder 11 , and the valve housing 2 accommodated in the housing 14 .

[0021] The valve housing 2 separates the compression side chamber R2 in the cylinder 11 and the liquid storage chamber R formed by the annular gap between the cylinder 11 and the housing 14. The extension side chamber R1 and the compression side chamber R2 in the cylinder 11 are filled with liquid, and the liquid storage chamber R is filled with gas and liquid. It should be noted that the liquid filled in the buffer body 10 may be hydraulic oil, water, aqueous solution, or other liquids.

[0022] Furthermore, when the buffer D is extended, the rod 12 is withdrawn from the cylinder 11, and as the volume of the withdrawn rod 12 decreases and the volume in the cylinder increases, the liquid storage chamber R supplies liquid into the cylinder 11. Conversely, when the buffer D is contracted, the rod 12 enters the cylinder 11, and as the volume of the entered rod 12 increases and the volume in the cylinder decreases, the liquid in the cylinder 11 is discharged into the liquid storage chamber R.

[0023] As described above, the shock absorber D of the present embodiment is composed of a single-rod, multi-tube shock absorber, and the volume of the rod 12 entering or exiting the cylinder 11 is compensated by supplying or discharging liquid from the liquid storage chamber R to the cylinder 11 .

[0024] The rod 12 includes a small diameter portion 12a provided at the front end side and a Figure 1 A step portion 12c at the junction with the large diameter portion 12b on the upper middle side and a threaded portion 12d provided on the outer periphery of the front end of the small diameter portion 12a.

[0025] Next, the piston 13 is annular and is fitted on the outer periphery of the small diameter portion 12a of the rod 12. The piston nut 21 is screwed on the threaded portion 12d of the rod 12 to be fixed to the rod 12. Figure 1 More specifically, the piston 13 slides in contact with the inner circumference of the cylinder 11 and divides the interior of the cylinder 11 into Figure 1 The expansion-side chamber R1 at the upper middle portion and the compression-side chamber R2 at the lower middle portion are provided with an expansion-side port 13a and a compression-side port 13b for communicating the expansion-side chamber R1 and the compression-side chamber R2.

[0026] In the piston 13 Figure 1 An extension side damping valve 16 and a gasket 17 are overlapped on the middle and lower surfaces, wherein the extension side damping valve is annular and consists of a stacked leaf valve fixed on the inner side to the small diameter portion 12a of the rod 12, allowing the outer side to bend and opening or closing the extension side port 13a, and the gasket is also annular and is used to set the position of the bending fulcrum of the extension side damping valve 16.

[0027] In addition, at the piston 13 Figure 1A compression side check valve 18 and a gasket 19 overlap on the middle upper surface, wherein the compression side check valve is annular and the inner peripheral side is fixed to the small diameter portion 12a of the rod 12, allowing the outer peripheral side to bend and can open or close the compression side port 13b, and the gasket is also annular and is used to set the position of the bending fulcrum of the compression side check valve 18.

[0028] After these gaskets 19, compression side check valve 18, piston 13, extension side damping valve 16 and gasket 17 are assembled in sequence on the outer periphery of the small diameter portion 12a of the rod 12, they are clamped and fixed to the rod 12 by the piston nut 21 screwed on the threaded portion 12d at the front end of the rod 12 and the step portion 12c of the rod 12.

[0029] The extension side damping valve 16 is a laminated leaf valve formed by laminating a plurality of annular plates. As described above, the inner periphery of the laminated leaf valve 16 is fixed to the rod 12 and laminated to the piston 13. Figure 1 The lower end of the expansion side damping valve 16 can open or close the outlet end of the expansion side port 13a of the piston 13, and is provided with a cutout orifice 16a on the outer periphery, and the cutout orifice always connects the expansion side port 13a with the compression side chamber R2. Therefore, the expansion side damping valve 16 connects the expansion side port 13a with the compression side chamber R2 only through the cutout orifice 16a when the opening end of the expansion side port 13a is closed.

[0030] Furthermore, if the side of the extension side port of the expansion side damping valve 16 is the front side, the pressure in the expansion side chamber R1 acting on the front side through the expansion side port 13a is higher than the pressure in the compression side chamber R2 acting on the back side. When the difference between the pressures reaches the valve opening pressure, the outer periphery is bent to open the valve, and the expansion side port 13a is opened. If the expansion side damping valve 16 is bent so that the outer periphery is away from the piston 13, an annular gap is formed between the piston 13, and the expansion side port 13a is connected to the compression side chamber R2 through the gap, and resistance is applied to the flow of the liquid flowing through the expansion side port 13a. It should be noted that in the shock absorber D of the present embodiment, when the expansion speed of the shock absorber D is in the high speed range, the expansion side damping valve 16 is opened to apply resistance to the flow of the liquid flowing from the expansion side chamber R1 to the compression side chamber R2 through the expansion side port 13a.

[0031] The other compression side check valve 18 is composed of a plurality of stacked annular plates, the inner periphery of which is fixed to the rod 12 and stacked on the piston 13. Figure 1At the middle and upper end, the outlet end of the compression side port 13b of the piston 13 can be opened or closed. Moreover, the pressure in the compression side chamber R2 is higher than the pressure in the extension side chamber R1. When the pressure difference between the two reaches the valve opening pressure, the compression side check valve 18 bends the outer periphery to open the valve, so that the compression side port 13b is opened. The compression side check valve 18 opens the valve when the outer periphery is bent away from the piston 13, opens the compression side port 13b, and allows the liquid to flow through the compression side port 13b from the compression side chamber R2 to the extension side chamber R1. It should be noted that the valve opening pressure of the compression side check valve 18 is set very low, and the compression side check valve 18 is set not to impose too much resistance on the flow of liquid flowing through the compression side port 13b when the valve is opened.

[0032] Furthermore, although the extension side damping valve 16 is composed of a plurality of stacked annular plates, the number of stacked annular plates can be arbitrarily changed according to the damping force expected to be generated by the buffer D, and can even be composed of only one annular plate. In addition, although the compression side check valve 18 is composed of a plurality of stacked annular plates, the number of stacked annular plates can be arbitrarily changed, and can even be composed of only one annular plate. The extension side damping valve 16 and the compression side check valve 18 can also be valves other than valves composed of annular plates, but if they are valves using thin annular plates, the advantage is that the total length of the piston portion of the buffer D is not increased, and the stroke length of the buffer D is more easily ensured.

[0033] In addition, the inner circumferences of the extension-side damping valve 16 and the compression-side check valve 18 are supported by the gaskets 17 and 19, respectively, and the outer circumferences not supported by the gaskets 17 and 19 are allowed to bend. Therefore, by setting the outer diameters of the gaskets 17 and 19, the positions of the bending fulcrums of the extension-side damping valve 16 and the compression-side check valve 18 can be changed. It should be noted that the gaskets 17 and 19 may be composed of a plurality of annular linings.

[0034] The damping valve 1 includes a valve housing 2 serving as a valve seat member, a sub-valve 3, and a leaf valve 4. The valve housing 2 includes a ring-shaped inner portion and a lower portion of the inner portion. Figure 2 A base portion 2a at the middle lower end and a cylindrical portion 2b hanging down from the outer periphery of the lower end of the base portion 2a.

[0035] The base 2a of the valve housing 2 is provided with: a compression side damping port 2c, which is a plurality of ports penetrating the base 2a vertically; an annular recess 2d, which is provided at the base 2a; Figure 2 The lower end of the valve seat 2e is connected to the opening end of the compression side damping port 2c; the annular valve seat 2e is the base 2a Figure 2 The lower and middle end stands up from the outer periphery of the recess 2d; the relatively set portion 2f, which is annular and has an inner peripheral surface facing the recess 2d; a plurality of suction ports 2g, which pass through the base 2a up and down and are configured to be closer to the outer peripheral side than the compression side damping port 2c of the base 2a.

[0036] A plurality of compression side damping ports 2c are arranged as ports at equal intervals along the same circumference relative to the base 2a, passing through the base 2a vertically, and communicating with the compression side chamber R2 and the internal space of the cylinder 2b. The recess 2d is annular and is connected to the compression side damping port 2c. Figure 2 The openings at the middle and lower ends are connected. Figure 3 As shown, the concave portion 2d is formed by an annular bottom 2d1 opening at the compression side damping port 2c, an annular conical inner wall 2d2 as the wall portion on the inner peripheral side of the bottom, and an annular outer wall 2d3 as the wall portion on the outer peripheral side of the bottom having a circumferential surface perpendicular to the base 2a, and its shape is such that the opening area faces Figure 3 In addition, at the base 2a Figure 2 An inner peripheral seat surface 2h having an annular shape and a flat surface is provided at a position at the lower middle end and closer to the inner periphery than the recessed portion 2d.

[0037] like Figure 3 As shown, the valve seat 2e is arranged at the lower end of the base 2a from the outer circumference of the recess 2d to the Figure 2 The valve seat 2e protrudes downward from the bottom of the base 2a, and has an annular seat surface 2e1 on which the leaf valve 4 can be seated and an inclined surface 2e2 connected to the outer periphery of the recess 2d, surrounding the outer periphery of the compression side damping port 2c. Figure 2 The bottom 2d1 of the recess 2d is disposed at a position lower than the inner peripheral seat surface 2h on the inner peripheral side of the recess 2d. Therefore, when viewed from the base 2a, the seat surface 2e1 is higher than the inner peripheral seat surface 2h, and a height difference is provided between the two. In addition, since the bottom 2d1 of the recess 2d is formed at Figure 2 The bottom portion 2d1 is disposed at a position higher than the inner peripheral seat surface 2h, and therefore, when viewed from the base portion 2a, the bottom portion 2d1 is lower than the inner peripheral seat surface 2h, with a height difference being provided therebetween.

[0038] In addition, in the damping valve 1 of the present embodiment, the opposing portion 2f is formed by the outer wall 2d3 which forms the recessed portion 2d of the base portion 2a and has an inner peripheral surface facing the recessed portion 2d.

[0039] The plurality of suction ports 2g are provided at equal intervals along the same circumference with respect to the base portion 2a, penetrate the base portion 2a vertically, and communicate with the compression side chamber R2 and the space in the cylinder portion 2b.

[0040] The base 2a of the valve housing 2 is fitted into the cylinder 11. Figure 2On the inner periphery of the middle and lower end, the lower end of the cylinder 2b abuts against the bottom 14a of the housing 14. Moreover, the valve housing 2 is clamped by the cylinder 11 and the bottom 14a of the housing 14, and the compression side chamber R2 in the cylinder 11 is separated from the liquid storage chamber R located between the cylinder 11 and the housing 14. A plurality of cutouts 2b1 are provided at the lower end of the cylinder 2b of the valve housing 2, and the space in the cylinder 2b of the valve housing 2 is connected to the liquid storage chamber R through the cutouts 2b1. Furthermore, the space in the cylinder 2b of the valve housing 2 is connected to the compression side chamber R2 via the compression side damping port 2c and the suction port 2g. In this way, the compression side chamber R2 is connected to the liquid storage chamber R via the compression side damping port 2c and the suction port 2g.

[0041] In the damping valve 1 of the present embodiment, the auxiliary valve 3 is an annular plate, whose inner diameter is equal to the inner diameter of the base 2a and whose outer diameter is smaller than the inner peripheral surface of the opposite setting portion 2f formed by the outer wall 2d3 of the recess 2d, and overlaps with the inner peripheral seat surface 2h provided at the lower end of the base 2a of the valve housing 2. In addition, on the side of the auxiliary valve 3 opposite to the valve seat member, the following are sequentially stacked: a gasket 5, whose inner diameter is equal to the inner diameter of the auxiliary valve 3 and whose outer diameter is smaller than the outer diameter of the auxiliary valve 3; a valve stopper 6, whose inner diameter is equal to the inner diameter of the auxiliary valve 3 and whose outer diameter is smaller than the outer diameter of the auxiliary valve 3 and larger than the outer diameter of the gasket 5; a leaf valve 4, which can be seated on the seat surface 2e1 of the valve seat 2e; and an annular limiting member 20, which limits further bending of the leaf valve 4 when it abuts against the leaf valve 4. As described above, although the auxiliary valve 3 is composed of one annular plate, the number of annular plates constituting the auxiliary valve 3 may be changed. Furthermore, if the auxiliary valve 3 is composed of a plurality of annular plates, the outer diameters of the annular plates may be different from each other.

[0042] On the compression side chamber side of the base 2a of the valve housing 2, a valve body 2 is overlapped with a valve body 2a that can open or close the suction port 2g. Figure 2 The annular suction check valve 7 and the gasket 8 at the upper middle end, i.e., the open end. It should be noted that the suction check valve 7 is composed of a plurality of overlapping annular plates, and has a through hole 7a that passes through the annular plates from top to bottom. Therefore, even if the suction check valve 7 is brought into contact with the base 2a, the compression side damping port 2c can always be connected to the compression side chamber R2 through the through hole 7a, so the suction check valve 7 will not block the compression side damping port 2c.

[0043] Moreover, the shaft portion 9b of the guide rod 9 is inserted into the inner periphery of the gasket 8, the suction check valve 7, the base 2a of the valve housing 2, the auxiliary valve 3, the gasket 5, the valve stopper 6, the leaf valve 4 and the limiting component 20 as a shaft component having a head portion 9a and a shaft portion 9b, and the gasket 8, the suction check valve 7, the base 2a of the valve housing 2, the auxiliary valve 3, the gasket 5, the valve stopper 6, the leaf valve 4 and the limiting component 20 are clamped by a nut 30 screwed on the front end of the head portion 9a and the shaft portion 9b.

[0044] The inner periphery of the auxiliary valve 3 is clamped and fixed by the gasket 5 and the inner peripheral seat surface 2h of the base 2a, and the outer periphery is a free end, allowing the outer periphery to bend. A height difference is set between the inner peripheral seat surface 2h of the base 2a and the bottom 2d1 forming the recess 2d, and a height difference is also set between the seat surface 2e1 that can be separated from the seat of the leaf valve 4. A gasket 5 and a valve stopper 6 are provided between the leaf valve 4 and the auxiliary valve 3, and a gap is formed between the auxiliary valve 3 and the leaf valve 4 to allow the outer periphery of the auxiliary valve 3 to bend. The auxiliary valve 3 is stacked on the gasket 5 and configured to be away from the bottom 2d1 in the recess 2d, so as not to block the compression side damping port 2c as a port, and to allow the auxiliary valve 3 to bend in a direction away from the valve housing 2 (i.e., Figure 3 Lower middle) bend.

[0045] The outer diameter of the gasket 5 is smaller than the outer diameter of the auxiliary valve 3, and a fulcrum is formed at the outer edge of the end surface facing the auxiliary valve 3, which is bent in the direction of the valve housing 2 away from the auxiliary valve 3. Therefore, the auxiliary valve 3 can use the outer edge of the gasket 5 as a fulcrum to make the outer periphery of the auxiliary valve 3 bend laterally. Figure 2 The bending fulcrum of the auxiliary valve 3 can be adjusted by setting the outer diameter of the gasket 5, and the bending amount of the auxiliary valve 3 when it abuts against the valve stopper 6 can also be adjusted by changing the stacking number or thickness of the gasket 5.

[0046] It should be noted that the auxiliary valve 3 can use the outer edge of the inner peripheral seat surface 2h as a fulcrum to make the outer peripheral side Figure 2 The height difference between the bottom 2d1 of the recess 2d and the inner peripheral seat surface 2h is sufficiently set to ensure that the auxiliary valve 3 Figure 2 The upper middle bend will not block the compression side damping port 2c.

[0047] When the auxiliary valve 3 is not bent, Figure 3 In the initial installation state shown, the outer peripheral surface is directly opposite to the inner peripheral surface of the annular relative setting portion 2f, and there is a predetermined annular gap P between the relative setting portion 2f. It should be noted that, in the damping valve 1 of this embodiment, the annular gap P formed between the mutually opposite auxiliary valve 3 and the relative setting portion 2f is very narrow, and the opening area of ​​the annular gap P is smaller than the opening area of ​​the cutout throttle hole 4a provided on the leaf valve 4 described later.

[0048] The outer diameter of the valve stopper 6 is larger than the outer diameter of the gasket 5 and smaller than the outer diameter of the auxiliary valve 3, and is composed of an elastic annular plate. Figure 2 When the lower middle part is bent and abuts against the valve stopper 6 , the side of the auxiliary valve 3 opposite to the valve seat member abuts against the valve stopper 6 and supports the auxiliary valve 3 , thereby limiting the bending of the auxiliary valve 3 .

[0049] The leaf valve 4 is a laminated leaf valve composed of a plurality of annular plates. As mentioned above, the inner periphery is fixed to the valve housing 2 by the guide rod 9, and the outer periphery is seated on the seat surface 2e1 of the valve seat 2e provided on the valve housing 2. Figure 2 The outer diameter of the annular plate on the uppermost valve seat 2e is larger than the outer diameter of the auxiliary valve 3, and a cutout orifice 4a is provided on the outer periphery. Therefore, when the leaf valve 4 is seated on the valve seat 2e, the compression side damping port 2c surrounded by the valve seat 2e is communicated with the reservoir R only through the cutout orifice 4a.

[0050] Furthermore, if the leaf valve 4 has the surface on the valve housing side, that is, the valve seat member side, as the front side, then when the differential pressure between the pressure acting on the front side of the compression side chamber R2 through the compression side damping port 2c and the pressure acting on the back side of the liquid storage chamber R reaches the valve opening pressure, the outer periphery is bent and moves away from the valve seat 2e. If the leaf valve 4 moves away from the valve seat 2e, an annular gap is formed between the leaf valve and the valve seat 2e, and the compression side damping port 2c is connected to the liquid storage chamber R through the gap, and resistance is applied to the flow of liquid flowing through the compression side damping port 2c. In the damping valve 1 of the present embodiment, when the contraction speed of the damper D is in the high speed range, the leaf valve 4 opens and resistance is applied to the flow of liquid flowing from the compression side chamber R2 to the liquid storage chamber R through the compression side damping port 2c. In addition, the leaf valve 4 is set as a one-way passage that allows only the flow of liquid from the compression side chamber R2 to the liquid storage chamber R through the compression side damping port 2c.

[0051] In addition, the inner periphery of the leaf valve 4 is in contact with the valve stopper 6 on the side opposite to the valve seat side end (i.e. Figure 2 Compared with the lower and middle ends of the valve seat 2e, the valve seat 2e protrudes downward more, and a height difference (height difference) is set between the two. If the leaf valve 4, the auxiliary valve 3, the gasket 5 and the valve stopper 6 are overlapped on the valve housing 2, and the inner peripheral side is fixed to the outer periphery of the shaft portion 9b of the guide rod 9, the outer periphery will bend due to the height difference. In this way, the leaf valve 4 is given an initial bend in advance, and uses the elastic force generated by it to press itself against the valve seat 2e. Therefore, the leaf valve 4 will not open until the differential pressure between the pressure in the compression side chamber R2 and the pressure in the storage chamber R causes the bending force of the leaf valve 4 to exceed the pressing force generated by the above-mentioned elastic force, and the differential pressure when the valve is opened is the valve opening pressure of the leaf valve 4. Therefore, the valve opening pressure of the leaf valve 4 can be adjusted by the bending rigidity of the leaf valve 4 and the initial bending amount applied to the leaf valve 4.

[0052] It should be noted that although the leaf valve 4 is composed of a plurality of stacked annular plates, the number of stacked annular plates can be arbitrarily changed according to the damping force expected to be generated by the buffer D, and can even be composed of only one annular plate. In addition, the notched throttle hole 4a can be provided on the leaf valve 4 by engraving or the like to provide a concave portion having the function of a throttle hole, instead of or in addition to providing the notched throttle hole 4a on the leaf valve 4.

[0053] As described above, the inner periphery of the suction check valve 7 is fixed to the guide rod 9 together with the gasket 8 and is stacked on the base 2a of the valve housing 2. Figure 2 The gasket 8 is annular, and its inner diameter is set to be the same as that of the suction check valve 7, and its outer diameter is set so as not to block the through hole 7a of the suction check valve 7. Therefore, the suction check valve 7 uses the outer edge of the valve seat part side end of the gasket 8 as a fulcrum to allow the outer periphery to move laterally. Figure 2 The upper part of the curve.

[0054] Moreover, when the pressure in the liquid storage chamber R is higher than the pressure in the compression side chamber R2, and the pressure difference between the two reaches the valve opening pressure, the suction check valve 7 bends the outer periphery to open the valve, so that the suction port 2g is opened. In addition, the suction check valve 7 opens the valve when the outer periphery is bent away from the valve housing 2, opens the suction port 2g, and allows the liquid to flow from the liquid storage chamber R to the compression side chamber R2 through the suction port 2g. It should be noted that the valve opening pressure of the suction side check valve 7 is set very low, and the suction side check valve 7 is set not to apply too much resistance to the flow of liquid flowing through the suction side port 2g when the valve is opened. Although the suction side check valve 7 is composed of a plurality of stacked annular plates, the number of stacked annular plates can be changed arbitrarily, or it can be composed of only one annular plate. In addition, a cutout throttle hole can be set on the suction check valve 7, or a recessed portion used as a throttle hole can be set on the valve seat of the suction check valve 7 that can be seated.

[0055] The damping valve 1 and the shock absorber D of this embodiment are configured as described above. The operation of the damping valve 1 and the shock absorber D will be described below. First, the state when the shock absorber D is extended will be described. Figure 1 In the embodiment, when the rod 12 moves upward relative to the cylinder 11 and the housing 14, that is, when the buffer D is extended, the piston 13 moves upward relative to the cylinder 11. Figure 1The expansion side chamber R1 moves upward and compresses the expansion side chamber R1, and expands the compression side chamber R2. If the expansion speed of the buffer D is low, since the difference between the pressure in the compressed expansion side chamber R1 and the pressure in the expanded compression side chamber R2 does not reach the valve opening pressure of the expansion side damping valve 16, the liquid in the expansion side chamber R1 flows through the expansion side port 13a and the cut-out throttle hole 16a and moves toward the compression side chamber R2. In addition, in the expanded compression side chamber R2, since the rod 12 withdraws from the cylinder 11, there is a lack of liquid corresponding to the volume of the rod 12 withdrawing from the cylinder 11, and the suction check valve 7 opens, and the insufficient liquid is supplied from the liquid storage chamber R to the compression side chamber R2 through the suction port 2g. When the buffer D extends, the suction check valve 7 opens quickly to open the suction port 2g, so that the liquid moving from the storage chamber R to the compression side chamber R2 will flow through the suction port 2g, and will not flow through the cut-out throttle hole 4a, the annular gap P between the auxiliary valve 3 and the relatively set part 2f, and the compression side damping port 2c.

[0056] Thus, when the extension speed of the buffer D is low, the buffer D applies resistance to the flow of the liquid flowing through the extension side port 13a through the cutout orifice 16a, thereby generating a damping force that hinders the extension of the buffer D. Therefore, if the extension speed of the buffer D is low, the characteristic of the damping force generated by the buffer D relative to the piston speed, that is, the extension side damping force characteristic, is as follows: Figure 4 As shown, it is proportional to the square of the piston speed unique to the throttle hole.

[0057] In addition, if the extension speed of the buffer D becomes high, the difference between the pressure in the compressed extension side chamber R1 and the pressure in the expanded compression side chamber R2 reaches the valve opening pressure of the extension side damping valve 16, and the extension side damping valve 16 opens, thereby opening the extension side port 13a. In this way, when the extension speed of the buffer D is high, the buffer D applies resistance to the flow of the liquid flowing through the extension side port 13a through the extension side damping valve 16, thereby generating a damping force that hinders the extension of the buffer D. Therefore, the damping force characteristics of the extension side of the buffer D when it is extended at a high speed are as follows: Figure 4 As shown, the damping coefficient becomes lower than that at low speeds, and is a characteristic unique to leaf valves that is proportional to the piston speed.

[0058] Next, the situation when the buffer D is contracted will be described. Figure 1 In the embodiment, when the rod 12 moves downward relative to the cylinder 11 and the housing 14, that is, when the buffer D contracts, the piston 13 moves downward relative to the cylinder 11. Figure 1The compression side chamber R2 moves downward and the compression side chamber R2 is compressed, and the extension side chamber R1 is expanded. Due to the contraction of the buffer D, the compression side check valve 18 opens, and the liquid in the compressed compression side chamber R2 moves to the expanded extension side chamber R1 through the compression side port 13b without encountering much resistance. In addition, when the buffer D contracts, since the rod 12 enters the cylinder 11, there will be excess liquid in the cylinder 11 corresponding to the volume of the rod 12 entering the cylinder 11, so the pressure in the cylinder 11 rises. Since the pressure in the compression side chamber R2 is higher than the pressure in the liquid storage chamber R, the suction check valve 7 is closed, thereby blocking the suction port 2g. Therefore, the excess liquid flows through the compression side damping port 2c and moves from the compression side chamber R2 to the liquid storage chamber R. When the contraction speed of the buffer D is low, since the difference between the pressure in the compressed compression side chamber R2 and the pressure in the liquid storage chamber R does not reach the valve opening pressure of the leaf valve 4, the liquid in the compression side chamber R2 will move to the liquid storage chamber R through the compression side damping port 2c, the annular gap P between the auxiliary valve 3 and the relatively set part 2f and the cut-out throttling hole 4a.

[0059] The auxiliary valve 3 of the damping valve 1 bends when the rod 12 moves in the contraction direction relative to the cylinder 11, and the bending amount of the auxiliary valve 3 increases as the contraction speed of the buffer D increases. Moreover, when the contraction speed of the buffer D is close to 0 (zero) at the beginning of the action, the bending amount of the auxiliary valve 3 is very small. Between the slightly low speed range and the low speed range, the auxiliary valve 3 bends to the extent that it cannot be opposite to the inner peripheral surface of the relative setting part 2f, and the auxiliary valve 3 opens. Furthermore, when the contraction speed of the buffer D is low or high, the outer peripheral portion of the auxiliary valve 3 bends with the outer peripheral edge of the gasket 5 as the fulcrum. Figure 3 The lower side of the auxiliary valve 3 is greatly bent. When the auxiliary valve 3 bends away from the relative setting portion 2f and opens, the pressure difference between the pressure in the compression side chamber R2 and the liquid storage chamber R, that is, the valve opening pressure of the auxiliary valve 3 will be lower than the valve opening pressure of the leaf valve 4. When the contraction speed is in the low speed range, the auxiliary valve 3 opens as described above, but the leaf valve 4 does not open, and the liquid moves from the compression side chamber R2 to the liquid storage chamber R through the annular gap P and the cutout throttle hole 4a.

[0060] It should be noted that if the annular gap P is basically 0 when the auxiliary valve 3 is facing the inner circumferential surface of the relatively set part 2f, a differential pressure will immediately occur between the compression side chamber R2 and the liquid storage chamber R after the buffer D starts to move, so when the buffer D switches from an extension action to a contraction action, the buffer D can quickly generate a damping force.

[0061] In this way, when the contraction speed of the shock absorber D is low or high, the outer peripheral portion of the auxiliary valve 3 moves Figure 3The opening area of ​​the annular gap P formed between the auxiliary valve 3 which is greatly bent in the lower middle part and deviated downward and the relative setting part 2f is larger than the opening area of ​​the cutout throttle hole 4a.

[0062] Therefore, when the contraction speed of the shock absorber D is in the micro-low speed range and close to 0, although the pressure in the compression side chamber R2 rises, the differential pressure between the pressure in the compression side chamber R2 and the pressure in the reservoir R does not reach the valve opening pressure of the leaf valve 4, so the leaf valve 4 does not open and keeps the compression side damping port 2c blocked. In addition, since the differential pressure does not reach the valve opening pressure of the auxiliary valve 3, even if the auxiliary valve 3 is bent and the axial width range of the outer peripheral surface and the inner peripheral circumference of the opposing portion 2f is relatively closed, the flow path area of ​​the annular gap P between the auxiliary valve 3 and the opposing portion 2f is maintained within a very small range. The liquid flows through the compression side damping port 2c, the annular gap P and the cutout throttle hole 4a and moves from the compression side chamber R2 to the liquid storage chamber R. However, since the flow path area of ​​the annular gap P on the auxiliary valve 3 in the closed valve state is smaller than the flow path area of ​​the cutout throttle hole 4a, when the contraction speed of the buffer D is in the micro-low speed range, the buffer D mainly generates a damping force that hinders its contraction through the resistance applied to the liquid by the auxiliary valve 3. Therefore, when the contraction speed of the buffer D is in the micro-low speed range, the damping force characteristics of the compression side of the buffer D are as follows: Figure 4 As shown in FIG. 1 , when the contraction speed is close to 0, the damping coefficient increases greatly, and then the damping coefficient decreases due to the opening of the auxiliary valve 3. In this way, when the shock absorber D contracts at a slightly low speed, the damping force is generated by the auxiliary valve 3, so that the shock absorber D can generate a sufficient damping force to suppress its vibration when it starts to expand and contract, thereby improving the ride comfort of the vehicle.

[0063] Therefore, when the contraction speed of the buffer D is low, the buffer D mainly generates a damping force that hinders contraction through the resistance applied to the liquid by the cutout orifice 4a. Therefore, when the contraction speed of the buffer D is low, the damping force characteristics of the compression side of the buffer D are as follows: Figure 4 As shown, the damping coefficient is proportional to the square of the contraction speed of the shock absorber D which is unique to the orifice, but becomes smaller than when the contraction speed is in the slightly low speed range.

[0064] Furthermore, when the contraction speed of the buffer D increases and changes from the micro-slow speed range to the low speed range, the differential pressure between the pressure in the compression side chamber R2 and the pressure in the liquid storage chamber R exceeds the valve opening pressure of the auxiliary valve 3, so the auxiliary valve 3 bends the outer periphery from the inner peripheral axial width range of the relative setting portion 2f to the inner periphery of the relative setting portion 2f. Figure 3The valve is opened by deviating from the middle and lower part, so that the flow path area of ​​the annular gap P between the auxiliary valve 3 and the relative setting part 2f is larger than the flow path area of ​​the cutout throttle hole 4a. If the auxiliary valve 3 is bent and cannot be opposite to the relative setting part 2f, the outer periphery of the auxiliary valve 3 is opposite to the valve seat 2e. Since the inclined surface 2e2 is provided on the inner periphery of the valve seat 2e, when the auxiliary valve 3 is bent, the flow path area between it and the valve housing 2 increases rapidly, so the auxiliary valve 3 can not affect the damping force of the buffer D when it contracts at a low speed.

[0065] In addition, the auxiliary valve 3 is bent and abuts against the valve stopper 6 and the leaf valve 4, so that it is supported by the valve stopper 6 and the leaf valve 4. The auxiliary valve 3 is supported in a state of being bent into an arch in the radial direction by two parts abutting against the valve stopper 6 and the leaf valve 4, thereby limiting the deformation along the width of the valve stopper 6 from the inner periphery to the outer periphery. When the auxiliary valve 3 is deformed by fluctuations, a large stress will act on the auxiliary valve 3 to cause fatigue, but since the valve stopper 6 and the leaf valve 4 can be used to support the two places on the back of the auxiliary valve 3 to prevent the deformation, the fatigue of the auxiliary valve 3 can be reduced.

[0066] Furthermore, when the contraction speed of the shock absorber D exceeds the low speed range and is in the high speed region, the differential pressure between the pressure in the compression side chamber R2 and the pressure in the liquid storage chamber R reaches the valve opening pressure of the leaf valve 4, and the leaf valve 4 bends to open the valve, thereby opening the compression side damping port 2c. When the contraction speed of the shock absorber D is high speed, since the difference between the pressure in the compression side chamber R2 and the pressure in the liquid storage chamber R exceeds the valve opening pressure of the auxiliary valve 3, the auxiliary valve 3 opens the valve, and the flow path area of ​​the annular gap P between the auxiliary valve 3 and the opposing setting portion 2f increases. As a result, the auxiliary valve 3 is kept in a state of contact with the valve stopper 6 and the leaf valve 4, and bends together with the valve stopper 6 and the leaf valve 4. Therefore, when the leaf valve 4 opens the valve to open the compression side damping port 2c, the auxiliary valve 3 can be prevented from squeezing the flow path area of ​​the compression side damping port 2c. Therefore, when the contraction speed of the shock absorber D is high speed, the auxiliary valve 3 bends greatly, and the flow path area of ​​the gap between the leaf valve 4 and the valve seat 2e is smaller than the flow path area of ​​the annular gap P. Therefore, when the contraction speed of the buffer D is high, the buffer D mainly generates a damping force that hinders contraction through the resistance applied to the liquid by the leaf valve 4. Therefore, when the contraction speed of the buffer D is high, the damping force characteristics of the compression side of the buffer D are as follows: Figure 4 As shown, it is proportional to the contraction speed of the shock absorber D unique to the leaf valve 4, but the damping coefficient becomes smaller than when the contraction speed is low.

[0067] In this way, since the sub-valve 3 is provided between the outlet end of the compression side damping port 2 c serving as a port and the leaf valve 4 , the sub-valve 3 in the damping valve 1 generates a damping force only when the damper D contracts.

[0068] The damping valve 1 and the damper D of the present embodiment operate as described above. The damping valve 1 of the present embodiment includes: a valve housing (valve seat member) 2 having an annular recess 2d, a compression side damping port (port) 2c opened at a bottom 2d1 of the recess 2d, an annular valve seat 2e rising from the outer periphery of the recess 2d, and an annular opposing portion 2f having an inner peripheral surface facing the recess 2d; a sub-valve 3 arranged away from the bottom 2d1 of the recess 2d in the recess 2d, an annular outer peripheral surface and an annular outer peripheral surface and an annular outer peripheral surface and the opposing portion 2f, and an outer peripheral side of the free end of the valve housing (valve seat member) 2 can be bent in the recess 2d in a direction away from the valve housing (valve seat member) 2; and a leaf valve 4 that is annular and stacked away from the axial direction on the side of the sub-valve 3 opposite to the valve seat member, and the outer peripheral side of the valve seat 2e can be bent as a free end and can be seated with respect to the valve seat 2e.

[0069] In the damping valve 1 constructed in this way, since a recessed portion 2d that can accommodate the auxiliary valve 3 and allow the auxiliary valve 3 to bend and a relatively set portion 2f opposite to the outer periphery of the auxiliary valve 3 are provided on the valve housing (valve seat component) 2 having a valve seat 2e on which the leaf valve 4 can be detached and seated, the valve housing (valve seat component) 2 can be used as a valve seat for both the auxiliary valve 3 and the leaf valve 4.

[0070] Therefore, in the conventional damping valve, although the auxiliary valve and the leaf valve are provided with valve housings and pistons etc. having valve seats, respectively, in the damping valve 1 of the present embodiment, the valve seats of both the auxiliary valve 3 and the leaf valve 4 can be concentrated on one valve housing (valve seat member) 2, which can reduce the number of components and shorten the total length. In addition, according to the damping valve 1, the valve seats of both the auxiliary valve 3 and the leaf valve 4 can be concentrated on one valve housing (valve seat member) 2, which can reduce the number of components, thereby improving assemblability. Furthermore, according to the damping valve 1, even when manufacturing a buffer D having different diameters of the cylinder 11, it is only necessary to make the valve housing (valve seat member) 2 correspond to the diameter of the cylinder 11, so that compared with the conventional damping valve, since the number of components can be reduced, it is easier to manage the components and reduce the manufacturing cost. In summary, according to the damping valve 1 of the present embodiment, the total length can be shortened, the price can be reduced, and the assemblability can be improved.

[0071] In addition, in the damping valve 1 of the present embodiment, since the auxiliary valve 3 is provided between the outlet end of the compression side damping port (port) 2c and the leaf valve 4, and the auxiliary valve 3 of the damping valve 1 has the suction port 2g that allows only the flow of liquid in the opposite direction to the compression side damping port (port) 2c, the damping force is generated by the auxiliary valve 3 only when the damper D contracts. In this way, the auxiliary valve 3 can be set as a single-acting valve that generates a damping force only in one direction when the damper D is extended or retracted, so that the damping force when the damper D is extended and the damping force when the damper D is retracted can be set independently.

[0072] It should be noted that the damping valve 1 of the present embodiment can also be applied to the piston portion of the buffer D. Therefore, for example, as with the valve housing (valve seat member) 2, if a recessed portion connected to the outlet end of the extension side port 13a, a valve seat surrounding the outer periphery of the recessed portion and allowing the extension side damping valve 16 to be seated, and a relatively arranged portion facing the recessed portion are provided on the piston 13, and the auxiliary valve 3 that allows the outer periphery to bend in the recessed portion is provided between the extension side damping valve 16 and the piston 13, then when the buffer D is extended, and when the extension is performed at a slightly low speed, the damping force can be generated by the auxiliary valve 3.

[0073] In this way, if the damping valve 1 is applied to the piston part and the bottom valve part of the buffer D set as a multi-tube type, when the buffer D is extended and contracted, the auxiliary valve 3 can provide a damping force sufficient to suppress the vibration of the buffer D when it starts to expand and contract. In addition, the auxiliary valve 3 mounted on the valve housing 2 of the bottom valve part does not affect the damping force when the buffer D is extended, and the auxiliary valve 3 mounted on the piston 13 of the piston part does not affect the damping force when the buffer D is contracted. Therefore, the damping force when the buffer D set as a multi-tube type is extended and the damping force when it is contracted can be set separately. In addition, the damping valve 1 of this embodiment is applied to the bottom valve of the buffer D, and can also be applied only to the piston part. In this way, even if the damping valve 1 is applied only to the piston part, the total length of the piston part will be shortened, which can achieve the effect of reducing the number of parts, reducing the price, and improving assemblability.

[0074] Thus, the shock absorber D comprises: a cylindrical housing 14; a telescopic shock absorber body 10 having a rod 12 movably inserted into the housing 14; and a damping valve 1. In the shock absorber body 10, the valve housing (valve seat member) 2 separates the compression side chamber (working room) R2 and the liquid storage chamber (working room) R, and the two chambers are connected through the compression side damping port (port) 2c. According to the shock absorber D of such a structure, since the total length of the damping valve 1 can be shortened, it is easy to ensure the stroke length, reduce the number of parts of the damping valve 1, and improve the assemblability.

[0075] It should be noted that in a single-rod type shock absorber in which the outer casing of the outer box constituting the shock absorber D is used as a cylinder, a bottom valve is not provided, and a damping valve is provided only on the piston portion. More specifically, in the single-rod type shock absorber, a piston connected to a rod is movably inserted on the inner periphery of the outer casing, the inner casing is divided into an extension side chamber and a compression side chamber by the piston, and the two chambers are connected through an extension side port and a compression side port also provided on the piston, a compression side leaf valve that can open or close the compression side port is provided on the extension side chamber side of the piston, and an extension side leaf valve that can open or close the extension side port is provided on the compression side chamber side of the piston, and a free piston is movably inserted into the outer casing, which divides an air chamber facing the compression side chamber in the outer casing to compensate for the volume of the rod entering and exiting the outer casing. For the piston in such a single-rod type shock absorber, if a recess is provided and an auxiliary valve is provided between the leaf valve and the piston, the structure of the damping valve 1 can be applied to the piston portion of the single-rod type shock absorber. In a single-rod type shock absorber, when the structure of the damping valve 1 is applied to the piston part, the auxiliary valve can be provided between the leaf valve on the extension side and the piston, and between the leaf valve on the compression side and the piston, or both. In addition, in such a single-rod type shock absorber, if the auxiliary valve is provided between the leaf valve on the extension side and the piston, and between the leaf valve on the compression side and the piston, the auxiliary valve allows both the flow of liquid from the extension side chamber to the compression side chamber and the flow of liquid from the compression side chamber to the extension side chamber through the port, and can bend the outer circumference toward the piston side and the leaf valve side. If a throttle hole is formed on the leaf valve on the extension side or the leaf valve on the compression side provided with the auxiliary valve, it can be used as a valve that generates a damping force when the shock absorber is extended and contracted. In this way, even if the structure of the damping valve 1 is applied to a single-tube type shock absorber, since one piston can be used as a valve seat for both the auxiliary valve and the leaf valve as a valve seat member, the total length of the piston part can be shortened, and the stroke length of the shock absorber can be more easily ensured.

[0076] Furthermore, the valve housing (valve seat member) 2 in the damping valve 1 of the present embodiment has an inclined surface 2e2 between the relative setting portion 2f and the seat surface 2e1 of the valve seat 2e on which the leaf valve 4 can be detachably seated. In this way, since the valve housing (valve seat member) 2 has the inclined surface 2e2, when the auxiliary valve 3 is bent, the flow path area of ​​the gap between the outer periphery of the auxiliary valve 3 and the valve housing (valve seat member) 2 is rapidly increased, so that the auxiliary valve 3 does not affect the damping force when the buffer D contracts at a low speed.

[0077] In addition, when the valve housing (valve seat member) 2 is manufactured by sintering, the inclined surface 2e2 is provided between the seat surface 2e1 of the valve seat 2e and the opposing portion 2f composed of a cylindrical surface perpendicular to the seat surface 2e1, so that there is no right angle formed by a fragile cross section between the opposing portion 2f and the seat surface 2e1, and therefore, the damping valve 1 of this embodiment can improve the durability of the valve seat (valve seat member) 2. Moreover, when the valve housing (valve seat member) 2 is manufactured by sintering, since the inclined surface 2e2 is provided between the opposing portion 2f and the seat surface 2e1, the durability of the valve seat (valve seat member) 2 can be improved, according to the damping valve 1, the opposing portion 2f can be arranged at a position close to the seat surface 2e1 of the valve seat 2e in the radial direction, and the degree of freedom in designing the inner diameter of the opposing portion 2f and the outer diameter of the auxiliary valve 3 can be improved. It should be noted that, in the present embodiment, the inclined surface 2e2 is a conical surface having a certain gradient in the cross section, but it may also be a curved surface, or an inclined surface with a gradient that changes in stages.

[0078] In addition, the damping valve 1 according to the present embodiment is provided with a valve stopper 6, which is disposed between the auxiliary valve 3 and the leaf valve 4, away from the auxiliary valve 3, is annular, allows bending of the outer peripheral side, and restricts bending deformation of the auxiliary valve 3 when the outer periphery of the auxiliary valve 3 bends and abuts in a direction away from the valve housing (valve seat member) 2. According to the damping valve 1 constructed in this way, when the auxiliary valve 3 abuts against the valve stopper 6 and bends in a direction away from the valve housing (valve seat member) 2, it is supported by the leaf valve 4 in addition to the valve stopper 6, so that the bending deformation of the auxiliary valve 3 can be suppressed, and fatigue of the auxiliary valve 3 can be reduced.

[0079] It should be noted that, in the above case, the outer peripheral side outer wall 2d3 of the concave portion 2d of the valve housing 2 as the valve seat member is provided as the opposing portion 2f which is opposed to the outer peripheral surface of the auxiliary valve 3 and forms an annular gap P with the outer periphery of the auxiliary valve 3. Figure 5 The damping valve 1A in the first variant shown has a valve housing 2 having: a valve seat component body B1 having a recess 2d, a valve seat 2e, and a compression side damping port 2c used as a port; and a ring 31 forming a relatively set portion 2f on the inner periphery of an outer peripheral wall 2d3 of the recess 2d on the valve seat component body B1.

[0080] The ring 31 is annular, and its inner diameter is larger than the outer diameter of the auxiliary valve 3. It is pressed into the inner periphery of the outer wall 2d3 of the recess 2d and fixed in the recess 2d. In this way, the valve housing 2 is provided with the ring 31, and the inner peripheral surface of the ring 31 is used as a relative setting portion facing the outer peripheral surface of the auxiliary valve 3. It should be noted that the axial height of the ring 31 is set to be smaller than the depth of the recess 2d, so that the ring 31 does not protrude axially from the recess 2d.

[0081] The auxiliary valve 3, the gasket 5, the valve stopper 6 and the leaf valve 4 are stacked on the inner peripheral seat surface 2h of the valve housing 2, and the inner periphery of the auxiliary valve 3, the gasket 5, the valve stopper 6 and the leaf valve 4 are fixed to the outer periphery of the shaft portion 9b of the guide rod 9 by the guide rod 9 and the nut 30. Thus, in the damping valve 1A of the first modified example, the valve housing (valve seat member) 2 is provided with a ring 31 mounted on the outer wall 2d3 of the recessed portion 2d, and the inner peripheral surface of the ring 31 is used as a relative setting portion, which is different from the above-mentioned damping valve 1.

[0082] The damping valve 1A of the first modified example thus constructed operates in the same manner as the damping valve 1, and when the damper D contracts at a very low speed, the sub-valve 3 generates a damping force. Furthermore, according to the damping valve 1A of the first modified example, the valve housing (valve seat member) 2 includes a ring 31 serving as a valve seat for the sub-valve 3 and a valve seat 2e for the leaf valve 4, so that, similar to the damping valve 1, the total length can be shortened, the number of parts can be reduced, and the assemblability can be improved. In addition, when the portion other than the ring 31 of the valve housing (valve seat member) 2, that is, the valve seat member body B1, is manufactured by sintering, the ring 31 having a high dimensional accuracy of the inner diameter can be mounted on the outer wall 2d3 of the recess 2d. Therefore, according to the damping valve 1A, the size of the annular gap P between the sub-valve 3 and the ring 31 is easily managed, and the desired damping force characteristics are more easily obtained. Furthermore, even if the valve housing (valve seat member) 2 is composed of the valve seat member body B1 and the ring 31, the ring 31 only needs to be fitted into the recess 2d, so that the valve housing (valve seat member) 2 can be manufactured and the assemblability can be improved.

[0083] In addition, if Figure 6 The damping valve 1B of the second modified example shown may contain a cup 32 in the recess 2d instead of the ring 31 and use the cup 32 as a facing portion. Specifically, the valve housing (seat member) 2 includes a seat member body B2 including the recess 2d and the cup 32.

[0084] The valve seat member body B2 includes a base 2a and a cylindrical portion 2b that hangs down from the outer periphery of the lower end of the base 2a. The base 2a is provided with: a plurality of compression side damping ports 2c that pass through the base 2a from top to bottom; an annular recess 2d that is provided at the base 2a; Figure 6 The lower end of the valve seat 2e is connected to the opening end of the compression side damping port 2c; the annular valve seat 2e is connected to the lower end of the compression side damping port 2c; Figure 6 The lower and middle ends stand up from the outer periphery of the recess 2d; the relatively set portion 2f is annular and has an inner peripheral surface facing the recess 2d; a plurality of suction ports 2g, which penetrate the base 2a up and down and are arranged at a position closer to the outer peripheral side than the compression side damping port 2c of the base 2a.

[0085] The recessed portion 2d is annular and is aligned with the compression side damping port 2c. Figure 6The openings at the middle and lower ends are connected. Figure 6 As shown in FIG. 1 , the recess 2d is formed by an annular bottom 2d4 and an outer wall 2d5, wherein the annular bottom is open at the compression side damping port 2c, and the outer wall is used as a wall portion on the outer peripheral side of the bottom 2d4, is annular, and has a peripheral surface perpendicular to the base 2a. In the valve housing 2 of the damping valve 1B, the bottom 2d4 in the recess 2d extends to the inner periphery of the base 2a, which is different from the damping valve 1.

[0086] The cup 32 is a bottomed cylindrical shape, and includes an annular bottom 32a, a cylindrical portion 32b rising from the outer periphery of the bottom 32a, and a plurality of arc-shaped holes 32c provided on the bottom 32a. Moreover, the inner diameter of the bottom 32a is the same as the inner diameter of the base 2a. When the cup 32 is inserted into the recess 2d and the bottom 32a is placed on the bottom 2d4 of the recess 2d, each compression-side damping port 2c is opposite to any of the holes 32c, and the compression-side damping port 2c is not blocked by the cup 32. In addition, in order to prevent the cylindrical portion 32b of the cup 32 from protruding from the axial direction of the recess 2d, the axial height of the cup 32 is set to be smaller than the depth of the recess 2d.

[0087] The gasket 33, which is annular and has a smaller diameter than the auxiliary valve 3, the auxiliary valve 3, the gasket 5, the valve stopper 6 and the leaf valve 4 are stacked in sequence on the bottom 32a of the cup 32, wherein the cup is accommodated in the recess 2d of the valve seat member body B2. The valve seat member body B2, the cup 32, the gasket 33, the auxiliary valve 3, the gasket 5, the valve stopper 6 and the leaf valve 4 are clamped by the guide rod 9 and the nut 30 inserted into the inner periphery, and fixed to the outer periphery of the shaft portion 9b.

[0088] In the damping valve 1B assembled in this way, the auxiliary valve 3 is arranged at a position away from the cup 32 through the gasket 33, and the outer periphery of the auxiliary valve 3 is opposite to the inner periphery of the cylinder 32b of the cup 32. The inner periphery of the cylinder 32b of the cup 32 is used as a relative setting portion, and an annular gap P is formed between the outer periphery of the auxiliary valve 3. In addition, even if the auxiliary valve 3 is stacked on the gasket 33, the height of the lower end of the auxiliary valve 3 is lower than the lower end of the auxiliary valve 3 when viewed from the valve housing 2. Figure 6 At the height of the lower end of the seat surface 2e1 of the middle valve seat 2e, the outer periphery of the sub-valve 3 can be bent in the recessed portion 2d in a direction away from the valve housing 2.

[0089] As described above, in the damping valve 1B of the second variant, the valve housing (valve seat component) 2 has a bottomed cylindrical cup 32 accommodated in the recessed portion 2d, the relatively setting portion is formed by the cylindrical portion 32b of the cup 32, and annular gaskets 5 and 33 having a smaller diameter than the auxiliary valve 3 are respectively clamped between the auxiliary valve 3 and the bottom 32a of the cup 32 and between the auxiliary valve 3 and the leaf valve 4, and a guide rod (shaft component) 9 is provided for maintaining the inner circumference of the valve housing (valve seat component) 2, the cup 32, the auxiliary valve 3, the gaskets 5 and 33 and the leaf valve 4.

[0090] The damping valve 1B of the second modified example thus constructed operates in the same manner as the damping valve 1, and when the damper D contracts at a slightly low speed, the sub-valve 3 generates a damping force. Furthermore, according to the damping valve 1B of the second modified example, the valve housing (valve seat member) 2 has a cup 32 serving as a valve seat for the sub-valve 3 and a valve seat 2e for the leaf valve 4, so that, as in the damping valve 1, the total length can be shortened, the number of parts can be reduced, and the assemblability can be improved. In addition, when the portion other than the cup 32 of the valve housing (valve seat member) 2, i.e., the valve seat member body B2, is manufactured by sintering, it is only necessary to accommodate the cup 32 having a high dimensional accuracy of the inner diameter of the cylindrical portion 32b in the recess 2d, so that according to the damping valve 1B, it is easier to manage the dimension of the annular gap P between the sub-valve 3 and the cylindrical portion 32b of the cup 32, and it is easier to obtain the desired damping force characteristics. In addition, even if the valve housing (valve seat member) 2 is composed of the valve assembly member body B2 and the cup 32, the valve housing (valve seat member) 2 can be obtained by accommodating the cup 32 in the recess 2d and fixing it with the guide rod (shaft member) 9, so that the assembly performance is improved. It should be noted that the damping valves 1A and 1B can also be applied to the piston part of the buffer D.

[0091] Although the preferred embodiments of the present invention have been described in detail above, modifications, variations and changes may be made without departing from the scope of the claims. Explanation of symbols

[0092] 1 Damping valve 2 Valve housing (valve seat component) 2c Compression side damping port (port) 2d concavity 2d1 Bottom 2d3 outer wall 2e Valve seat 2e1 Seat surface 2e2 Inclined surface 2f Relative setting part 3 Auxiliary valve 4 Leaf valve 5.33 Gasket 6 Valve stopper 9 Guide rod (shaft component) 10 Buffer body 12 Rods 14 Housing 31 rings 32 cup 32b Cylinder B1, B2 valve seat body D-Buffer R Liquid Storage Room (Studio) R2 compression side chamber (working room)

Claims

1. A damping valve, comprising: A valve seat member having an annular recess, a port opened at the bottom of the recess, an annular valve seat rising from the outer periphery of the recess, and an annular opposing portion having an inner peripheral surface facing the recess; The auxiliary valve is arranged in the recess and away from the bottom of the recess, is annular, forms an annular gap between the outer peripheral surface and the oppositely disposed portion, and the outer peripheral side as a free end can be bent in the recess in a direction away from the valve seat component; The leaf valve is annular and is disposed away from the axial direction on the side of the auxiliary valve opposite to the valve seat member, and the outer peripheral side is bendable as a free end so as to be seated on and off the valve seat.

2. The damping valve according to claim 1, wherein: The valve seat member has an inclined surface between the opposing portion and a seat surface of the valve seat on which the leaf valve can be seated.

3. The damping valve according to claim 1, wherein: The valve seat member has a ring mounted on an outer wall on an outer peripheral side forming the recessed portion. The opposing portion is formed by the inner peripheral surface of the ring.

4. The damping valve according to claim 1, wherein: The valve seat member has a bottomed cylindrical cup accommodated in the recessed portion. The oppositely disposed portion is formed by the cylindrical portion of the cup-shaped object, A gasket having a ring shape and a diameter smaller than that of the auxiliary valve is sandwiched between the auxiliary valve and the bottom of the cup-shaped object and between the auxiliary valve and the leaf valve. A shaft member is provided for holding the valve seat member, the cup, the sub-valve, the spacer, and the inner periphery of the leaf valve.

5. The damping valve according to claim 1, wherein: A valve stopper is provided between the auxiliary valve and the leaf valve and away from the auxiliary valve. The valve stopper is annular and allows bending of the outer peripheral side. When the outer periphery of the auxiliary valve bends in a direction away from the valve seat component and abuts, the valve stopper is used to limit the bending of the auxiliary valve.

6. A buffer, characterized in that have: a telescopic buffer body having a cylindrical housing and a rod movably inserted into the housing; The damping valve according to any one of claims 1 to 6, The valve seat member divides the inside of the damper body into two working chambers that communicate with each other through the port.

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