JP2022091485A - Buffer - Google Patents

Abstract

To provide a buffer having three stages or more of damping force properties in a single valve.SOLUTION: The buffer generates a first damping force property by an orifice having a certain opening area at a first operation pressure, generates a second damping force property by a flow passage in which the opening area of the valve is increased after a second operation pressure higher than the first operation pressure is reached, and generates a third damping force property by the flow passage in which the opening area of the valve is increased after a third operation pressure higher than the second operation pressure is reached.SELECTED DRAWING: Figure 2

Description

The present invention relates to a shock absorber which is provided in a vehicle such as a railway and suppresses vibration of the vehicle.

Patent Document 1 discloses a shock absorber in which a valve mechanism is provided in a closing member.

Japanese Unexamined Patent Publication No. 2014-62643

In a conventional shock absorber, one valve mechanism creates two characteristics, an orifice region and a relief region. When increasing this damping force characteristic, it is possible to create characteristics in three or more regions by further providing valve mechanisms having different characteristics. However, depending on the cost, the size and shape of the shock absorber, it may be difficult to provide a plurality of valve mechanisms, and there is a problem that it is difficult to increase the damping force characteristics.

An object of the present invention is to generate three or more damping force characteristics of a shock absorber according to a region with a single valve.

In order to solve the above problems, the present invention divides the inside of the cylinder into a first fluid chamber and a second fluid chamber by being movably inserted into the cylinder and a cylinder in which the working fluid is sealed. A piston rod that is connected to the piston in the cylinder and whose tip extends to the outside of the cylinder, an outer cylinder that is arranged on the outer periphery of the cylinder and forms a reservoir chamber between the cylinder, and the cylinder. A closing member that closes the opening at one end of the cylinder, a flow path that communicates the inside of the cylinder with the reservoir chamber, and a flow path through which the working fluid flows, and a flow path provided in the flow path for the movement of the piston. It is provided with a valve mechanism that suppresses the flow of the working fluid that accompanies it to generate an operating pressure, and an orifice passage that always allows the flow of the working fluid that accompanies the movement of the piston with a flow path resistance. The valve mechanism is a shock absorber, and the valve mechanism includes a valve body, a valve body chamber in which the valve body is movably housed, and a spring means for urging the valve body in a direction of closing the valve body. Is characterized by having a plurality of valve opening flow paths that are opened and closed at different positions when the valve body moves in the valve opening direction.

According to the present invention, it is possible to create three or more damping force characteristics by the action of one valve mechanism.

It is sectional drawing which shows the whole of the shock absorber which concerns on this embodiment. It is an enlarged view around the valve structure of the shock absorber of FIG. It is a damping force characteristic diagram generated by the valve structure of a conventional shock absorber. 2 is an enlarged view of the valve structure according to the present embodiment when the valve is closed. FIG. 2A is a cross-sectional view taken along a uniaxial plane of the valve structure, and FIG. 2B is a cross-sectional view taken along the line AA of FIG. 2A. 2 is an enlarged drawing of the valve structure according to the present embodiment of FIG. 2, where (a) is a cross-sectional view taken along a uniaxial plane of the valve structure, and (b) is a cross-sectional view taken along the line AA of (a). 2 is an enlarged view of the valve structure according to the present embodiment. FIG. 2A is a view of the valve body viewed from the direction of the second axis portion, and FIG. 2B is a modification of the valve body with the valve body as the second axis. It is a figure seen from the direction of the part. 2 is an enlarged view of a modified example of the valve structure according to the present embodiment when the valve is closed. FIG. 2A is a cross-sectional view taken along the uniaxial plane of the valve structure, and FIG. 2B is a cross-sectional view taken along the line AA of FIG. be. 2 is an enlarged view of a modified example of the valve structure according to the present embodiment when the valve is opened. FIG. 2A is a cross-sectional view taken along the uniaxial plane of the valve structure, and FIG. 2B is a cross-sectional view taken along the line AA of FIG. be. It is a damping force characteristic diagram generated by the valve structure of the shock absorber which concerns on this actual form.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to FIGS. 1 to 9.

Here, the present invention will be described using the shock absorber 1 arranged vertically. The upward direction (upper side) and the lower direction (lower side) of the mounted state coincide with the upper direction (upper side) and the lower direction (lower side) in FIG.

It should be noted that the present invention does not depend on the mounting direction, but may be a shock absorber mounted horizontally or diagonally.

The first embodiment is shown and described with reference to FIGS. 1 to 5.

As shown in FIG. 1, the shock absorber 1 has a double-cylinder structure in which a cylindrical outer cylinder 3 is provided on the outside of a cylindrical cylinder 2, and an annular reservoir chamber is provided between the cylinder 2 and the outer cylinder 3. 4 is formed, and the working fluid and a gas such as the atmosphere and compressed nitrogen are sealed in the reservoir chamber 4. The openings at both ends of the cylinder 2 and the outer cylinder 3 are closed by the upper closing member 70 and the lower closing member 6 having a circular outer circumference.

The upper closing member 70 is composed of an annular rod guide 5 and a seal cap 15.

Further, the lower closing member 6 includes a first lid member 7 (bottom cap) that closes the opening of the lower end portion of the outer cylinder 3 and a bottom valve main body 8 that closes the opening of the lower end portion of the cylinder 2. It is divided and configured.

A piston rod 9 is inserted inside the cylinder 2. A piston 10 is fixed to the lower end of the piston rod 9 and is slidably fitted into the cylinder 2. The inner space of the cylinder 2 is divided into a first fluid chamber 2A and a second fluid chamber 2B by the piston 10. The piston 10 is provided with a check valve 11 that allows the flow of the working fluid from the second fluid chamber 2B to the first fluid chamber 2A. Instead of the check valve 11 of the piston 10, a pressure regulating valve that generates a damping force may be used, or the piston 10 is regulated to allow the flow of the working fluid from the first fluid chamber 2A to the second fluid chamber 2B. A pressure valve and a relief valve for releasing the pressure may be further provided.

Further, the bottom valve main body 8 of the lower closing member 6 (second lid member) is provided with a check valve 12 that allows only the flow of the working fluid from the reservoir chamber 4 to the second fluid chamber 2B. The check valve 12 may be a pressure regulating valve that generates a damping force, or may be provided with a relief valve that allows the flow of the working fluid from the second fluid chamber 2B to the reservoir chamber 4 and releases the pressure.

The position of the piston 10 fixed to the piston rod 9 is not limited to the lower end portion, for example, even if the piston 10 is arranged between the upper end portion and the lower end portion and the piston rod 9 extends to the lower closing member 6. good.

The upper end side of the piston rod 9 is inserted into the rod guide 5 and the seal cap 15 of the upper closing member 70 and extended to the outside of the cylinder 2. An oil seal and a dust seal (not shown) that are in sliding contact with the piston rod 9 are provided on the inner circumference of the seal cap 15, and a seal ring (not shown) that seals between the outer cylinder 3 and the seal cap 15 is provided on the outer peripheral side. Not shown) is provided.

The rod guide 5 is provided with a flow path 13 for the working fluid to flow from the first fluid chamber 2A to the reservoir chamber 4 by moving the piston rod 9 in the axial direction. The valve mechanism 14 is opened in the flow path 13 at a predetermined pressure, and the area of the flow path from the first fluid chamber 2A to the reservoir chamber 4 changes according to the amount of valve opening that changes with the change in pressure. Is provided. Further, the flow path 13 is an inflow path 16 that communicates the first fluid chamber 2A and the valve body chamber 20, and an outflow passage 18 that communicates the valve body chamber 20, the outflow port 18A of the valve body chamber 20, and the reservoir chamber 4. And include. A pipe 17 is connected to the reservoir chamber 4 side of the outflow passage 18 so as to extend downward in the axial direction of the piston rod 9. The lower end face of the pipe 17 has a length that fits into the working fluid stored in the reservoir chamber 4.

The valve mechanism 14 is roughly composed of a valve body chamber 20 and a valve body 19 housed therein. The valve body chamber 20 is formed by an opening in the outer peripheral surface 5A of the cylindrical rod guide 5 and a hole having a circular bottom formed radially inward from this opening (from right to left in FIG. 4). To. On the bottom surface of the valve body chamber 20, an inflow port 16A to which a radial portion 16B extending in the radial direction of the inflow path 16 is connected is provided in the center, and the valve body 19 is seated around the inflow port 16A. The annular sheet 29 is protruding. The contact portion between the seat 29 and the valve body 19 constitutes the first valve portion 43. An outlet 18A is connected and opened to the lower portion of the inner peripheral surface of the valve body chamber 20. Further, the inner peripheral surface of the valve body chamber 20 has a small diameter portion 20A on the bottom side and a large diameter portion 20B on the opening side.

Further, the valve body chamber 20 has a female screw 21 formed at the opening side end portion of the inner peripheral surface. A spring receiving member 22 (shaft member) coaxially arranged with respect to the valve body 19 is screwed onto the female screw 21 to close the opening of the valve body chamber 20. The spring receiving member 22 is inserted into a substantially disk-shaped spring receiving portion 26 in which a male screw 23 screwed into the female screw 21 is formed on the outer peripheral surface to receive one end of the valve spring 25, and inside one end of the valve spring 25. It has a valve body stopper 28 that regulates the stroke of the valve body 19 while positioning the valve spring 25 in the radial direction. A counterbore 24 is formed on the peripheral edge of the opening of the valve body chamber 20.

In the valve body stopper 28, when the valve body 19 comes into contact with the valve body stopper 28, the working fluid flowing from the small diameter portion 37B of the orifice hole 37 provided in the valve body 19 described later flows into the valve body chamber 20. A groove extending in the radial direction may be provided.

The valve body 19 has a columnar first shaft portion 31 inserted inside the valve spring 25, a flange-shaped spring receiving portion 33 for receiving the other end of the valve spring 25, and an inflow port 16A from the spring receiving portion 33. It is composed of a columnar second shaft portion 32 extending toward.

The outer diameters of the first shaft portion 31, the second shaft portion 32, and the flange-shaped spring receiving portion 33 of the valve body 19 are formed coaxially. Around the spring receiving portion 33, a circular portion 33A having substantially the same diameter as the small diameter portion 20A of the valve body chamber 20 (a diameter having a size having a gap enough to move smoothly) and a notch portion separated from the small diameter portion 20A. 33B is formed. The notch 33B constitutes a first valve opening flow path 41 that communicates the inflow path 16 and the valve body chamber 20 when the valve body 19 is opened. As shown in FIG. 6A, the cutout portions 33B are arranged at three locations, for example, the outer peripheral portion of the spring receiving portion 33. These three notches 33B are arranged at equal intervals in the circumferential direction of the spring receiving portion 33. As in the modified example shown in FIG. 6B, the notch 33B may be arranged at two locations, for example, the outer peripheral portion of the spring receiving portion 33.

The second shaft portion 32 of the valve body 19 is formed with a groove portion 34 that penetrates in the radial direction and extends to the end face in the inflow path 16 direction. The end of the groove 34 on the spring receiving portion 33 side has a bottom surface 34A substantially perpendicular to the axis of the valve body 19. The shape of the bottom surface 34A may be an arc shape. The position of the bottom surface 34A is arbitrarily set according to the required damping force characteristics. Further, the valve body 19 is formed with an orifice hole 37 having an opening at one end in the bottom surface 34A, extending in the axial direction of the valve body 19 and communicating the inflow path 16 and the valve body chamber 20. The orifice hole 37 has a large diameter portion 37A on the inflow path 16 side and a small diameter portion 37B on the valve body chamber 20 side, and the small diameter portion 37B has a fixed damping force value that changes depending on the size and constantly generates a damping force. It is an orifice. Inside the spring receiving portion 33, one end is opened at the outer periphery of the circular portion 33A of the spring receiving portion 33, and the other end is a radial hole extending in the radial direction of the valve body 19 opening at the large diameter portion 37A of the orifice hole 37. 37C is formed. The radial hole 37C is closed when the spring receiving portion 33 faces the small diameter portion 20A of the valve body chamber 20 (a slight leakage that does not substantially affect the damping force characteristics occurs), and the hole 37C is large. It is configured to open when facing the diameter portion 20B. The second valve portion 44 is formed between the radial hole 37C and the small diameter portion 20A, and the flow path from the large diameter portion 37A of the orifice hole 37 to the radial hole 37C constitutes the second valve opening flow path 42. do.

Next, the operation of the shock absorber 1 of the embodiment will be described.

During the extension stroke of the piston rod 9, the check valve 11 provided in the piston 10 closes, the pressure of the working fluid in the first fluid chamber 2A rises, and the working fluid flows into the valve mechanism 14. Then, until the first operating pressure at which the valve body 19 starts to move, the valve body 19 flows into the inflow path 16 and passes through the orifice hole 37. As a result, the working fluid flows from the first fluid chamber 2A to the reservoir chamber 4, and the damping force of the orifice characteristic A in FIG. 9 corresponding to the flow path area of the small diameter portion 37B of the orifice hole 37 is generated. This is the state shown in FIG.

When the working pressure rises, exceeds the first working pressure and reaches the second working pressure, the valve body 19 opens against the spring force of the valve spring 25, and the first valve portion 43 is opened. .. At this time, the radial hole 37C of the orifice hole 37 is closed, and the second valve opening flow path 42 continues to be shut off. As a result, the working fluid passes from the first fluid chamber 2A through the first valve opening flow path 41 and flows to the reservoir chamber 4, and the working fluid flows from the first fluid chamber 2A to the reservoir chamber 4, and the working fluid corresponds to the flow path area between the valve body 19 and the seat 29. The damping force of the valve characteristic B is generated.

The flow path area of the first valve opening flow path 41 is larger than the flow path area between the valve body 19 and the seat 29, and a damping force is predominantly generated between the valve body 19 and the seat 29.

Further, when the working pressure rises and reaches the second working pressure higher than the first working pressure, the valve opening amount of the valve body 19 increases, and the radial hole 37C of the orifice hole 37 opens. The second valve portion 44 opens, and the second valve opening flow path 42 enters a communicating state. As a result, the working fluid passes from the first fluid chamber 2A through the second valve opening flow path 42 and flows to the reservoir chamber 4, and the damping force of the relief characteristic C of FIG. 9 according to the flow path area is generated. This is the state shown in FIG.

As described above, the damping force on the extension side corresponding to the moving speed of the piston 10 corresponding to the operating pressure of the first fluid chamber 2A is generated. At the time of the extension side stroke, the working fluid corresponding to the amount of the piston rod 9 ejected from the cylinder 2 is replenished from the reservoir chamber 4 to the second fluid chamber 2B via the check valve 12.

On the other hand, during the contraction stroke of the piston rod 9, the check valve 12 provided in the bottom valve main body 8 opens, the pressure of the working fluid in the second fluid chamber 2B rises, and the working fluid moves from the second fluid chamber 2B. It flows to the first fluid chamber 2A via the check valve 11 of the piston 10. As a result, the pressure of the working fluid in the first fluid chamber 2A and the pressure of the working fluid in the second fluid chamber 2B are balanced. Further, the working fluid for which the piston rod 9 has entered the cylinder 2 flows from the first fluid chamber 2A to the reservoir chamber 4 via the valve body 19. As a result, the working pressure of the first fluid chamber 2A and the second fluid chamber 2B increases according to the moving speed of the piston 10, and a damping force on the contraction side is generated.

The principle and characteristics of generating the damping force are the same as those at the time of the extension stroke of the piston rod 9.

According to the first embodiment, in the low speed region of the moving speed of the piston 10 (the state before the valve body 19 is opened) in the operation of the shock absorber 1, the working fluid flows from the first fluid chamber 2A to the inflow path. 16 flows to the reservoir chamber 4 via the groove portion 34, the small diameter portion 37B of the orifice hole 37, the valve body chamber 20, the outflow passage 18, and the pipe 17, thereby obtaining the damping force of the orifice characteristic (orifice characteristic A). Can be done. Further, in the region where the moving speed of the piston 10 is in the medium speed region, the valve body 19 corresponding to the moving speed of the piston 10 opens, and the working fluid flows through the first valve opening flow path 41. At this time, the flow path area changes depending on the moving speed of the piston 10, and a damping force (valve characteristic B) is obtained. Further, in the high speed region of the moving speed of the piston 10, the second valve opening flow path 42 provided in the valve body 19 is opened, and the flow of the second valve opening flow path 42 is generated. As a result, the second valve opening flow path 42 obtains a characteristic (relief characteristic C) in which the flow path area is greatly changed by the movement of the valve body 19 according to the movement speed of the piston 10 and the damping force is hardly changed.

In this way, since the working fluid flows through different flow paths according to the amount of movement of the valve body 19, the rate of change in the flow path area of the valve flow path changes, and the valve characteristics are changed by this single valve body. And the damping force characteristic of the relief characteristic is obtained.

As described above, in the first embodiment, the valve body of one valve mechanism has different flow paths called the first valve opening flow path 41 and the second valve opening flow path 42, and these valve opening flow paths are The first valve portion 43 and the second valve portion 44 open and close respectively. Therefore, by the action of one valve mechanism, the orifice characteristic A before valve opening and the valve characteristic B after valve opening are obtained as in the prior art shown in FIG. 3, and the relief characteristic C shown in FIG. 9 is also obtained. It is possible to get it.

Further, in the first embodiment, since the orifice hole for generating the orifice characteristic A is also provided in the valve body 19, the orifice characteristic can be changed only by changing the valve body portion, that is, changing the shape of the valve body 19 and changing the valve spring 25. A, valve characteristic B, and relief characteristic C can be changed.

In the above embodiment, the orifice hole 37 is provided in the valve body 19, but the present invention is not limited to this, and the orifice hole 37 may be provided in the piston portion or the like. Also in this case, by adopting one valve mechanism, the valve characteristic B and the relief characteristic C after the valve opening can be obtained from the orifice characteristic A before the valve opening. Further, the characteristic can be changed by the valve body portion by changing only the valve characteristic B and the relief characteristic C.

Next, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8. The same or equivalent components as those of the first embodiment are given the same name and reference numeral, and detailed description thereof will be omitted.

In the second embodiment, the position of the second valve opening flow path 42 of the valve mechanism 14 of the first embodiment is changed, and other configurations are the same as those of the first embodiment.

Unlike the first embodiment, the valve body chamber 51 of the valve mechanism 50 has a single inner peripheral surface having a single diameter having no small diameter portion. A valve seat member 53 (shaft member) arranged coaxially with the valve body 52 provided in the valve body chamber 51 is screwed onto the female screw 21 provided on the inner peripheral surface. A male screw 23 screwed into the female screw 21 is formed on the outer periphery of the valve seat member 53 to receive a substantially disk-shaped spring receiving portion 26 for receiving one end of the valve spring 25, and the spring receiving portion 26 is inserted inside one end of the valve spring 25. It has a bottomed tubular valve body stopper 54 to be formed.

The valve body stopper 54 has a small diameter portion 54A (insertion portion) into which the third shaft portion 52B of the valve body 52 is slidably inserted, and a large diameter portion 54B having an inner diameter larger than the small diameter portion 54A on the bottom side thereof. It is formed. Further, a fluid chamber 55 is formed in the large diameter portion 54B of the valve body stopper 54, and the large diameter portion 54B has a communication passage 59 (communication hole) for communicating the fluid chamber 55 and the valve body chamber 51 in the radial direction. It is formed.

The valve body 52 includes a first shaft portion 31 inserted inside the valve spring 25, and a third shaft portion 52B protruding in the axial direction of the first shaft portion 31 to a diameter smaller than the outer diameter of the first shaft portion 31. It is composed of a flange-shaped spring receiving portion 33 having a circular outer diameter for receiving the other end of the valve spring 25, and a second shaft portion 32 extending from the spring receiving portion 33 toward the inflow port 16A. The space between the valve body 52 and the seat 29 and the outside of the spring receiving portion 33 form the first valve opening flow path 58. The third shaft portion 52B constitutes an insertion portion 53B to be inserted into the small diameter portion 54A of the valve body stopper 54.

The third shaft portion 52B is formed with an orifice hole 56 having an opening at one end in the bottom surface 34B, extending in the axial direction of the valve body 52, and communicating the inflow path 16 and the valve body chamber 51. The orifice hole 56 has a large diameter portion 56A on the inflow path 16 side and a small diameter portion 56B on the valve body chamber 51 side, and the small diameter portion 56B is a fixed orifice that constantly generates a damping force.

A second valve opening flow path 60 extending in the radial direction is formed in the third shaft portion 52B by opening one end to the outer periphery of the insertion portion 53B and opening the other end to the large diameter portion 56A of the orifice hole 56. .. In the state of FIG. 7 in which the valve body 52 is in the closed state, the second valve opening flow path 60 faces the small diameter portion 54A of the valve body stop 54 and is closed, and the valve body 52 moves to the right side. Then, when the state shown in FIG. 8 is reached, the large diameter portion 54B is opposed to the large diameter portion 54B and is opened. The second valve opening flow path 60 and the small diameter portion 54A constitute the fourth valve portion 61.

According to the second embodiment, in the low speed region of the moving speed of the piston 10 (the state before the valve body 52 is opened) in the operation of the shock absorber 1, the working fluid flows from the first fluid chamber 2A to the inflow path. The fluid flows to the reservoir chamber 4 via the 16, groove portion 34, the valve body chamber 51, the outflow passage 18, and the pipe 17, whereby the damping force of the orifice characteristic (orifice characteristic A) can be obtained. Further, in the region where the moving speed of the piston 10 is in the medium speed region, the valve body 52 and the seat 29 are separated from each other by the amount of movement of the valve body 52 according to the moving speed of the piston 10, and the flow path area between them changes. The valve opening flow path 58 opens to obtain a damping force (valve characteristic B). Further, in the high speed region of the moving speed of the piston 10, the second valve opening flow path 60 provided in the valve body 52 is opened facing the large diameter portion 54B, and the working fluid flows into the valve body chamber 51. As a result, the flow path area changes greatly depending on the amount of movement of the valve body 52 according to the movement speed of the piston 10, and a characteristic (relief characteristic C) in which the damping force hardly changes is obtained. In this way, as in the first embodiment, the rate of change in the flow path area of the valve flow path through which the working fluid flows varies according to the amount of movement of the valve body, and a plurality of elements are operated by the action of a single valve mechanism. Obtain damping force characteristics.

In each of the above embodiments, the case where the present invention is used for a uniflow structure shock absorber is shown, but the present invention is not limited to this, and it can also be used for a biflow structure shock absorber that allows flow in both directions at the piston portion. .. In this case, the valve mechanism 14 is also provided on the lower closing member 6. Further, although each of the above embodiments shows an example in which the valve mechanism is provided on the upper closing member 70, the valve mechanism may be provided on any member as long as it is provided between the cylinder and the reservoir.

Further, in each of the above embodiments, an example in which one valve mechanism is provided is shown, but the present invention is not limited to this, and a plurality of valve mechanisms may be provided. In this case, the characteristics may be different for each valve mechanism.

In each of the above embodiments, an example in which two valve opening flow paths having a valve portion are provided in one valve mechanism is shown, but three or more valve opening flow paths having a valve portion are provided in one valve mechanism. You may.

1 shock absorber, 2 cylinder, 2A 1st fluid chamber, 2B 2nd fluid chamber, 3 outer cylinder, 4 reservoir chamber, 70 upper closing member, 5A outer peripheral surface, 6 lower closing member, 7 1st lid member, 8 bottom Valve body, 9 piston rod, 10 piston, 11 check valve, 12 check valve, 13 flow path, 14 valve mechanism, 16 inflow path, 16A inlet, 17 pipe, 18 outflow path, 18A outlet, 19 valve body , 20 valve chamber, 20A small diameter part, 20B large diameter part, 21 female screw, 22 spring receiving member, 23 male screw, 24 counterbore, 25 valve spring, 26 spring receiving part, 28 valve body stopper, 29 seat, 31 1st axis Part, 32 2nd shaft part, 33 spring receiving part, 33A circular part, 33B notch part, 34 groove part, 34A bottom surface, 34B bottom surface, 37 orifice hole, 37A large diameter part, 37B small diameter part, 37C radial hole, 41st 1 valve opening flow path, 42 second valve opening flow path, 43 first valve section, 44 second valve section, 50 valve mechanism, 51 valve body chamber, 52 valve body, 52B third shaft section, 53 valve seat member, 53A guide, 53B insertion part, 54 valve body stop, 54A small diameter part, 54B large diameter part, 55 fluid chamber, 56 orifice hole, 56A large diameter part, 56B small diameter part, 58 first valve opening flow path, 59 continuous passages, 60 Second valve opening flow path

Claims (1)

A cylinder with a working fluid inside and
A piston that is movably inserted into the cylinder and divides the inside of the cylinder into a first fluid chamber and a second fluid chamber.
A piston rod that is connected to the piston in the cylinder and whose tip extends to the outside of the cylinder.
An outer cylinder arranged on the outer periphery of the cylinder and forming a reservoir chamber between the cylinder and the outer cylinder.
A closing member that closes the opening at one end of the cylinder, and
A flow path that communicates the inside of the cylinder with the reservoir chamber and allows the working fluid to flow,
A valve mechanism provided in the flow path that suppresses the flow of the working fluid generated by the movement of the piston to generate working pressure.
An orifice passage that always allows the flow of the working fluid generated by the movement of the piston with a flow path resistance,
It is a shock absorber equipped with
The valve mechanism comprises a valve body, a valve body chamber in which the valve body is movably housed, and a spring means for urging the valve body in a direction of closing the valve body.
The valve mechanism is a shock absorber characterized by having a plurality of valve opening flow paths that are opened and closed at different positions when the valve body moves in the valve opening direction.

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