JP2013104477A - Shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a shock absorber in order to enable adjustment of damping force when working fluid passes through a one-side flow passage.SOLUTION: A shock absorber D includes: a piston 1 that demarcates a cylinder into one chamber A and the other chamber B; a one-side flow passage 10 that is formed in the piston 1 and communicates both chambers A, B with each other; a one-side leaf valve 11 that is stacked on the other-chamber side of the piston 1 and closes an outlet of the one-side flow passage 10; a piston rod 2 that holds the piston 1 and in which one side penetrates through the one chamber A while the other side protrudes into the other chamber B; a jack chamber J that is formed in the other chamber B; a jack member 3 that is axially movable along with expansion and contraction of the jack chamber J; a jack flow passage L that is formed in the piston rod 2; and an adjusting member 5 that is mounted on the one side of the piston rod 2 and supplies/discharges jack fluid into/from the jack chamber J via the jack flow passage L. It is configured to adjust spring force of a biasing spring 4, which biases the one-side leaf valve 11 to the closing side, by the movement of the jack member 3.

Description

  The present invention relates to an improvement of a shock absorber.

  In general, in a vehicle such as an automobile or a motorcycle, a suspension device is interposed between a vehicle body and wheels. This suspension device includes a spring called a suspension spring, and the suspension spring absorbs an impact caused by road surface unevenness. Further, the suspension device includes a shock absorber in parallel with the suspension spring in order to suppress the expansion and contraction motion accompanying the shock absorption of the suspension spring.

  For example, the shock absorber D1 shown in FIG. 3 is mounted on a front fork that is a suspension device for suspending a front wheel of a motorcycle. The cylinder 6 and an axial direction (vertical direction in FIG. 3) in the cylinder 6 are mounted. A piston rod 2 as a shaft member movably inserted and a piston 1 as a valve disk held by the piston rod 2 are provided.

  The cylinder 6 is partitioned by the piston 1 into an upper chamber A in FIG. 3 and a lower chamber B in FIG. The piston 1 has a one-side flow passage 10 that allows only movement of the working fluid from the one chamber A to the other chamber B, and a second that allows only movement of the working fluid from the other chamber B to the one chamber A. A side flow path 10a is formed.

  Further, the shock absorber D1 is laminated on the other chamber side (lower side in FIG. 3) of the piston 1, and closes the outlet of the one-side flow path 10 so as to be openable and closable. The other-side leaf valve 11a is stacked on the one-chamber side (upper side in FIG. 3) and closes the outlet of the other-side flow path 10a so as to be opened and closed.

  When the one chamber A is pressurized as the shock absorber D1 expands and contracts, the working fluid in the one chamber A opens the one side leaf valve 11, passes through the one side flow path 10, and moves to the other side chamber B. . When the other chamber B is pressurized, the working fluid in the other chamber B opens the other leaf valve 11a, passes through the other channel 10a, and moves to the one chamber A. At this time, the shock absorber D1 generates a damping force due to resistance when the working fluid passes through the flow paths 10 and 10a, and suppresses the expansion and contraction motion of the front fork.

  Subsequently, the piston rod 2 in the shock absorber D1 holds the piston 1 and has one side extending upward in FIG. 3 and passing through one chamber A, and the other side extending downward in FIG. The shock absorber D1 is a double rod shock absorber.

  An adjuster (not shown) is attached to one side (upper side in FIG. 3) of the piston rod 2 penetrating the one chamber A, and the valve opening pressure of the other leaf valve 11a can be adjusted by this adjuster. it can.

  Specifically, the damping force adjusting means for adjusting the valve opening pressure of the other leaf valve 11a is arranged in the one chamber A and is movable in the axial direction of the piston rod 2 (vertical direction in FIG. 3). A seat member 90 disposed, a valve pressing member 91 formed in a cylindrical shape and having a tip abutting against the outer peripheral portion of the other leaf valve 11a, and the other leaf disposed between the seat member 90 and the valve pressing member 91. An urging spring 92 that urges the valve 11a in the closing direction, a push rod 93 that is inserted in the axial center of the piston rod 2 so as to be movable in the axial direction, and whose tip abuts against the seat member 90, and the push rod And an adjuster (not shown) that contacts the proximal end side of 93 and drives the sheet member 90 through the push rod 93.

  Since the seat member 90 and the push rod 93 are sandwiched between the biasing spring 92 and the adjuster, they move in the axial direction as the adjuster moves. Thereby, the spring force of the urging spring 92 can be changed to adjust the valve opening pressure of the other-side leaf valve 11a, and the damping force generated when passing through the other-side passage 10a can be adjusted.

JP 2009-264489 A

  Here, in the buffer D1, when the damping force when the working fluid passes through the one-side flow path 10 closed by the one-side leaf valve 11, the one-side leaf valve 11 is pressed in the closing direction. That is, it is necessary to apply a force to the upper side in FIG.

  However, with the adjuster that transmits the force with the push rod 93 from one side of the piston rod 2 (upper side in FIG. 3), the force can be applied only to the lower side in FIG.

  Since the shock absorber D1 shown in FIG. 3 is a double rod type shock absorber, if an adjuster for transmitting force with the bush rod is provided from the other side of the piston rod 2 (lower side in FIG. 3), the piston rod 2, the damping force when the working fluid passes through the one-side flow path 10 by adjusting the one-side leaf valve 11 from the other side (the lower side in FIG. 3) can be adjusted. The above adjustment could not be made from the upper side in FIG.

  Accordingly, an object of the present invention is to reduce the damping force when the working fluid passes through a flow path closed by a leaf valve stacked on the other chamber side of a disk valve such as a piston from one side of a shaft member such as a piston rod. It is to provide a shock absorber that can be adjusted.

  Means for solving the above-described problems include a valve disc that is divided into one chamber and the other chamber, a flow passage that is formed in the valve disc and communicates the one chamber and the other chamber, and the other of the valve discs. A leaf valve stacked on the chamber side and closing the outlet of the flow path so as to be openable and closable, passing through the valve disc and the axial center of the leaf valve, one side passing through the one chamber, and the other side protruding into the other chamber In a shock absorber comprising a shaft member, a jack chamber formed in the other chamber, a jack member movable in the axial direction as the jack chamber expands and contracts, and the jack chamber formed in the shaft member and A jack flow path that always communicates, and an adjustment member that is attached to one side of the shaft member and that feeds and discharges the jack fluid to and from the jack chamber via the jack flow path. Is to adjust the spring force of the urging spring for biasing the leaf valve to the valve disk side by the movement of the jack members.

  According to the present invention, it is possible to adjust the damping force when the working fluid passes through the flow path closed by the leaf valve stacked on the other chamber side of the disk valve from one side of the shaft member.

It is a front view which shows the use condition of the buffer which concerns on one embodiment of this invention, and is partially cut away and shown. It is the longitudinal cross-sectional view which expanded and showed the principal part of the shock absorber which concerns on one embodiment of this invention, and was seen from the front side. It is the front view which expands and shows the principal part of the conventional shock absorber, and is partially cut away.

  A shock absorber according to an embodiment of the present invention will be described below with reference to the drawings. The same reference numerals given throughout the several drawings indicate the same or corresponding parts.

  As shown in FIG. 1, a shock absorber D according to the present embodiment includes a piston 1 that is a valve disk that is divided into one chamber A and the other chamber B, and the one chamber A and the other chamber that are formed in the piston 1. It is a leaf valve that is laminated on the other chamber side (lower side in FIG. 1) of the piston 1 so as to open and close the outlet of the one side channel 10 so as to be openable and closable. The one side leaf valve 11, the piston 1 and the shaft of the one side leaf valve 11 pass through, and one side (upper side in FIG. 1) passes through the one chamber A and the other side (lower side in FIG. 1). Includes a piston rod 2 as a shaft member protruding into the other chamber B.

  Further, the shock absorber D includes a jack chamber J formed in the other chamber B, a jack member 3 that is movable in the axial direction (vertical direction in FIG. 1) as the jack chamber J expands and contracts, A jack flow path L formed on the piston rod 2 and always communicating with the jack chamber J, and the jack attached to one side (upper side in FIG. 1) of the piston rod 2 and the jack flow path L. The chamber J is provided with an adjusting member 5 for supplying and discharging the jack fluid.

  Then, the spring force of the urging spring 4 that urges the one-side leaf valve 11 to the piston side (upper side in FIG. 1) is adjusted by the movement of the jack member 3.

  Hereinafter, in more detail, the shock absorber D according to the present embodiment is mounted on a front fork that is a suspension device for suspending a front wheel of a motorcycle. The front fork includes a suspension device body T including an outer tube T1 and an inner tube T2 that is movably inserted into the outer tube T1, and the suspension device body T includes the suspension device body T according to the present embodiment. A shock absorber D is accommodated.

  A suspension spring S that always urges the front fork in the extending direction is accommodated in parallel with the shock absorber D in the suspension device main body T, and the vehicle body is elastically supported by the suspension spring S.

  Further, a reservoir R is formed between the suspension device body T and the shock absorber D. A working fluid is accommodated in the reservoir R, and a gas that generates a reaction force when the suspension main body T is compressed is accommodated on the upper side via the liquid level O. In the present embodiment, the working fluid is made of oil, and the gas is made of an inert gas such as nitrogen.

  And the upper side in FIG. 1 of the said suspension apparatus main body T is obstruct | occluded with the cap member C1 attached to the upper end part in FIG. 1 of outer tube T1. On the other hand, the lower side of the suspension device main body T in FIG. 1 is closed by a bottom bracket (not shown) attached to the lower end of the inner tube T2 in FIG. Further, a cylindrical gap (not shown) formed between the outer tube T1 and the inner tube T2 in the suspension device main body T is attached to the inner periphery of the lower end portion of the outer tube T1 in FIG. Is closed by an annular oil seal C2 and a dust seal C3 which are in sliding contact with the outer peripheral surface of the oil. Thereby, the working fluid and gas accommodated in the reservoir R are prevented from leaking outside the suspension device main body T.

  Subsequently, the shock absorber D according to the present embodiment housed in the suspension device main body T is suspended from the cylinder 6 standing at the axial center portion of the inner tube T2 and the cap member C1. 6 includes a piston rod 2 that is a shaft member that is removably inserted into the piston 6, and a piston 1 that is a valve disk held by the piston rod 2.

  The inside of the cylinder 6 is partitioned by the piston 1 which is the valve disc. One chamber A is formed on the piston rod side (upper side in FIG. 1), and the other chamber B is formed on the piston side (lower side in FIG. 1). Is done. The one chamber A and the other chamber B are filled with a working fluid common to the working fluid stored in the reservoir R. Further, the upper opening in FIG. 1 of the cylinder 6 is closed by an annular rod guide 60.

  The piston rod 2 inserted into the cylinder 6 includes a cylindrical member 20 disposed on one side that is the upper side in FIG. 1 and a tip member 21 that is coaxially connected to the cylindrical member 20. The tip member 21 penetrates the axial center of the piston 1 and holds the piston 1. Further, the other end of the piston rod 2 which is the lower end in FIG. 1 of the piston rod 2 is disposed in the other chamber B, and the shock absorber D according to the present embodiment is a single rod type shock absorber. The

  One end portion of the piston rod 2 that is the upper end portion in FIG. 1 of the cylindrical member 20 is screwed into an adjuster 50 that is attached to an attachment hole C10 that penetrates the axial center portion of the cap member C1. It is locked. Further, the lower side of the cylindrical member 20 in FIG. 1 is pivotally supported by a bearing member 60a fitted to the inner periphery of the rod guide 60, and is movable in the axial direction (vertical direction in FIG. 1).

  On the other hand, as shown in FIG. 2, the tip member 21 has a large-diameter portion 21a that is screwed into the cylindrical member 20, and is coaxially connected to the large-diameter portion 21a and has a smaller diameter than the large-diameter portion 21a. An intermediate diameter portion 21b, a small diameter portion 21c coaxially connected to the intermediate diameter portion 21b and formed to have a smaller diameter than the intermediate diameter portion 21b, and a screw portion connected coaxially to the small diameter portion 21c and formed with a screw groove on the outer periphery. 21d and a distal end portion 21e that is coaxially connected to the screw portion 21d and is the leading edge of the distal end member 21.

  The tip member 21 has a valve stopper 12a, a spacer 13a, a pressure side check valve V2 composed of a plurality of other side leaf valves 11a, a piston 1, and an extended side leaf composed of a plurality of one side leaf valves 11 on the outer periphery of the small diameter portion 21c. The valve V1, the spacer 13, and the spacer 14 are mounted in this order from the upper side in FIG. 2, and the nut 23 is screwed into the screw portion 21d. As a result, the piston 1, the expansion side damping valve V1, the pressure side check valve V2, the valve stopper 12a, the spacers 13 and 13a, and the spacer 14 are stepped portions 21f formed at the boundary between the medium diameter portion 21b and the small diameter portion 21c. And the nut 23 to be fixed to the tip member 21.

  An annular valve stopper 12 for the extension side damping valve V1 is slidably contacted with the outer peripheral surface of the spacer 14 so as to be movable in the axial direction. The valve stopper 12 can move from the spacer 13 disposed in the other chamber B to the nut 23.

  Subsequently, the piston 1 held by the piston rod 2 has a one-side flow passage 10 that allows only the movement of the working fluid from one chamber A to the other chamber B, and the other chamber B to the one chamber A. The other-side flow path 10a that allows only the movement of the working fluid is formed.

  The inlet of the one-side channel 10 is always in communication with the one chamber A, and the outlet of the one-side channel 10 is stacked on the other chamber B side (lower side in FIG. 2) of the piston 1. It is closed by an extension side damping valve V1 composed of one side leaf valve 11 so as to be opened and closed. Further, the inlet of the other channel 10a is always in communication with the other chamber B, and the outlet of the other channel 10a is a plurality of other layers stacked on the one chamber side (upper side in FIG. 2) of the piston 1. The pressure side check valve V2 including the side leaf valve 11a is closed so as to be opened and closed.

  Returning, a base member (not shown) is fixed to the bottom part (lower part in FIG. 1) of the cylinder 6. Since the structure of this base member is well known, it is not shown in the figure. However, the base member includes an extension-side flow passage that allows only movement of the working fluid from the reservoir R to the other chamber B, and the other chamber B to the reservoir R. A pressure-side flow path that allows only the movement of the working fluid to is formed.

  The inlet of the extension side channel is always in communication with the reservoir R, and the outlet of the extension side channel can be opened and closed by an extension side check valve (not shown) stacked on one side of the base member on the other chamber side. Is blocked. The inlet of the pressure side channel is always in communication with the pressure side chamber B, and the outlet of the pressure side channel is closed by a pressure side damping valve (not shown) stacked on the other side of the base member. .

  Note that the compression side check valve V2 and the extension side check valve (not shown) are configured to generate only a small resistance when the working fluid passes through the other side channel 10a and the extension side channel. In contrast, the expansion side damping valve V1 and the pressure side attenuation valve (not shown) are set so as to generate a relatively large resistance when the working fluid passes through the one side flow path 10 and the pressure side flow path. The main damping force in the shock absorber D is generated by the damping valve V1 and the compression side damping valve.

  When the front fork extends so that the piston rod 2 moves out of the cylinder 6, the one chamber A is pressurized by the piston 1, and the working fluid in the one chamber A pushes open the expansion side damping valve V <b> 1 and opens the one side flow path 10. Pass through and move to the other chamber B.

  At this time, since the working fluid corresponding to the volume of the piston rod that has retreated is insufficient in the cylinder 6, the extension side check valve stacked on the base member (not shown) is opened, and the insufficient working fluid is supplied from the reservoir R to the base member. It passes through the extension channel and moves to the other chamber B.

  On the other hand, when the front fork in which the piston rod 2 enters the cylinder 6 is compressed, the other chamber B is pressurized by the piston 6, so that the pressure side check valve V2 is opened and the working fluid in the other chamber B is moved to the other side of the piston 1. It passes through the flow path 10a and moves to the extension side chamber A.

  At this time, in the cylinder 6, the working fluid for the volume of the piston rod that has entered becomes surplus, and the surplus working fluid passes through the pressure side flow path by pushing open the compression side damping valve laminated on the base member (not shown), The pressure side chamber B moves to the reservoir R.

  Therefore, the shock absorber D is attenuated due to resistance when the working fluid passes through each flow path formed in the piston 1 and a base member (not shown) when the front fork extends and retracts in the cylinder 6. Generates force and suppresses the expansion and contraction of the front fork. A change in the cylinder volume corresponding to the volume of the piston rod that appears and disappears in the cylinder 6 is compensated by the reservoir R.

  And the damping force (henceforth an extension side damping force) of the buffer D at the time of expansion | extension of a front fork can be adjusted with the adjustment member 5 attached to the one side (upper side in FIG. 1) of the piston rod 2. FIG. And this invention comprises the extension side damping force adjustment means which adjusts this extension side damping force in this Embodiment.

  The extension side damping force adjusting means includes a jack chamber J formed in the other chamber B, a jack member 3 movable in the axial direction (vertical direction in FIG. 1) in accordance with expansion and contraction of the jack chamber J, An urging spring 4 for urging the one-side leaf valve 11 toward the piston side (lower side in FIG. 1), a jack flow path L formed on the piston rod 2 and always communicating with the jack chamber J, and the jack chamber J includes the adjusting member 5 for supplying and discharging the jack fluid via the jack flow path L.

  As shown in FIG. 2, the jack chamber J includes a connecting member 7 screwed onto the outer periphery of the screw portion 21 d of the tip member 21, and a jack member 3 slidably contacting the outer peripheral surface of the connecting member 7 in the axial direction. Formed between.

  The connecting member 7 includes a bottom portion 70 and a cylindrical portion 71 that stands on the bottom portion 70, and is formed in a bottomed cylindrical shape. The cylindrical portion 71 is screwed into the screw portion 21d to be a tip portion. 21e is covered. Moreover, the outer peripheral part of the said bottom part 70 protrudes from the said cylindrical part 71, becomes a flange shape, and the outer peripheral surface of the connection member 7 is formed in the cross-section L-shape.

  The tubular portion 71 is formed with a communication hole 72 that allows the jack flow path L formed in the piston rod 2 to communicate with the jack chamber J. In addition, a hole 73 that penetrates the thickness of the bottom portion 70 is provided at the center of the bottom portion 70 of the connecting member 7.

  Further, the jack member 3 includes an annular lid portion 30 that is in sliding contact with the outer peripheral surface of the cylindrical portion 71 via a seal 30a, and a cylindrical partition wall portion 31 that is suspended from the outer peripheral end of the lid portion 30. And the inner peripheral surface of the jack member 3 is formed in an inverted L-shaped cross section. And the inner periphery of the partition part 31 is slidably contacted with the outer peripheral surface of the bottom part 70 of the said connection member 7 via the seal | sticker 70a.

  By providing the structure, the jack member 3 moves upward in FIG. 2 to enlarge the jack chamber J when the jack fluid is supplied to the jack chamber J. Further, when the jack fluid is discharged from the jack chamber J, the jack member 3 moves downward in FIG. 2 to reduce the jack chamber J.

  Subsequently, the urging spring 4 for urging the one-side leaf valve 11 toward the piston side (upper side in FIG. 2) is slidably contacted with the outer peripheral surface of the spacer 14 and is movable in the axial direction (vertical direction in FIG. 2). 12 and the jack member 3. Thereby, the spring force of the urging spring 4 can be changed by moving the jack member 3 in the axial direction.

  Subsequently, the jack flow path L communicating with the jack chamber J includes a cylindrical member inner flow path L1 that penetrates the cylindrical member 20 constituting the piston rod 2, and the piston rod 2 together with the cylindrical member 20. And a distal end member flow path L2 formed in the distal end member 21 constituting the above.

  One side, which is the upper side in FIGS. 1 and 2 of the flow path L1 in the cylindrical member, is slidably contacted with the inner periphery of the upper end portion of the cylindrical member 20 in FIG. It is blocked by. In addition, the other side of the tubular member internal flow path L1 communicates with the distal end member internal flow path L2. The inner peripheral surface of the cylindrical member 20 and the inner periphery of the tip member 21 are arranged at the boundary between the cylindrical member 20 and the tip member 21 so that the working fluid does not leak from the connecting portion of the cylindrical member 20 and the tip member 21. An annular seal member 9 is attached to the surface through seals 9a and 9b.

  Subsequently, the tip member inner flow path L2 passes through the tip member 21 in the axial direction and is connected to the axial center hole L20 connected to the tubular member inner flow path L1 through the thickness of the tip portion 21e of the tip member 21. A lateral hole L21 communicating with the communication hole 72 of the member 7 is provided.

  In the present embodiment, the distal end of the distal end portion 21e where the lateral hole L21 is formed is formed with a small diameter, and an annular gap 74 is formed between the tubular portion 71 of the connecting member 7. The horizontal hole L21 and the communication hole 72 communicate with each other through the gap 74, and even if the horizontal hole L21 and the communication hole 72 are displaced in the radial direction, the communication between the horizontal hole L21 and the communication hole 72 is hindered. There is no such thing.

  Further, the distal end side (lower side in FIG. 2) opening of the axial hole L20 faces the hole 73 of the connecting member 7, but the front end portion 21 e of the distal end member 21 and the bottom portion 70 of the connecting member 7. The rubber bush 24 is interposed between them.

  Further, a seal 25 is interposed between the cylindrical portion 71 of the connecting member 7 and the tip portion 21 e of the tip member 21, and the jack fluid flows from the connecting portion between the connecting member 7 and the tip member 21. There is no leakage, and the working fluid in the cylinder 6 does not flow from this connecting portion.

  That is, the jack chamber J and the jack flow path L are in one closed space filled with the jack fluid and are not mixed with the working fluid stored in the cylinder 6 or the reservoir R.

  The adjusting member 5 for supplying and discharging the working fluid into the jack chamber J via the jack flow path L is screwed into the adjuster 50 and is axially connected to the cap member C1 (vertical direction in the figure). The tip of the adjusting member 5 is in contact with a plug member 8 that closes the upper side of the jack flow path L in FIG. Thereby, the plug member 8 moves up and down in FIG. 1 together with the adjustment member 5.

  Further, the shock absorber D according to the present embodiment includes an extension spring 61 disposed between the tip member 21 of the piston rod 2 and the rod guide 60, and the extension fork 61 is used as a front fork. Absorbs the impact at the time of maximum extension.

  Next, the operation of the shock absorber D according to the present embodiment will be described. In the shock absorber D according to the present embodiment, when the adjustment member 5 is moved downward in FIG. 1 so as to approach the piston 1, it is pushed by the adjustment member 5 and the plug member 8 together with the adjustment member 5 in FIG. Move down.

  As the plug member 8 enters the piston rod 2, the jack fluid moves from the tubular member internal flow path L1 into the jack chamber J, and the jack member 3 is pushed upward in FIG. Expands. At this time, since the space between the jack member 3 and the valve stopper 12 is reduced, the spring force of the biasing spring 4 is increased.

  Further, since the jack chamber J and the jack flow path L are constantly pressurized through the biasing spring 4, when the adjustment member 5 is moved upward in FIG. The plug member 8 is pushed upward in FIG. 1 until the plug member 8 abuts against the adjusting member 5 by the internal pressure of the flow path L.

  Then, the amount of the jack fluid that the plug member 8 has retreated from the piston rod 2 moves from the jack chamber J to the tubular member internal flow path L1, and the jack member 3 is pushed down in FIG. to shrink. At this time, since the gap between the jack member 3 and the valve stopper 12 is increased, the spring force of the biasing spring 4 is decreased.

  That is, in the present embodiment, the plug member 8 is disposed on one side of the closed space that has the jack chamber J and the jack flow path L and is filled with the jack fluid, and the jack member 3 on the other side. Are movably disposed, and the jack member 3 can be driven to adjust the spring force of the biasing spring 4 by moving the plug member 8 with the adjusting member 5.

  Furthermore, one end of the biasing spring 4 in the present embodiment is in contact with the valve stopper 12 that is in sliding contact with the outer peripheral surface of the spacer 14. If the piston speed is in the middle or low speed range when the front fork is extended, only the outer peripheral end of the one-side leaf valve 11 constituting the expansion-side damping valve V1 bends and the valve stopper 12 does not function. The one-side leaf valve 11 does not receive the spring force of the biasing spring 4.

  However, when the piston speed reaches a high speed region when the front fork is extended, the outer peripheral portion of the one-side leaf valve 11 is greatly bent and comes into contact with the valve stopper 12, and the one-side leaf valve 11 is brought into the spring force of the biasing spring 4. Accordingly, the valve stopper 12 is pushed downward in FIG.

  That is, in the present embodiment, by changing the spring force of the biasing spring 4, the extension side damping force of the front fork (hereinafter referred to as the extension side high speed damping force) when the piston speed reaches the high speed range is obtained. Adjustment from the one side (upper side in FIG. 1) of the piston rod 2 can be performed by the adjustment member 5.

  Further, in the present embodiment, the jack fluid is made of oil and expands due to heat. Therefore, when the temperature becomes high, the jack member 3 moves upward in FIGS. 1 and 2 and the spring force of the biasing spring 4 increases. Thereby, even when the viscosity of the working fluid is reduced due to heat, the extension side high-speed damping force is automatically adjusted in a direction to increase, so that the extension side high-speed damping force can be kept constant.

  Further, in the present embodiment, since the jack chamber J is formed between the connecting member 7 and the jack member 3, the configuration for forming the jack chamber J can be simplified.

  Further, in the present embodiment, the connecting member 7 includes a bottom portion 70 and a cylindrical portion 71 that stands on the bottom portion 70 and is formed into a bottomed cylindrical shape, and the outer peripheral portion of the bottom portion 70 is the cylindrical portion 71. A lid portion 30 that protrudes from the outer periphery of the cylindrical portion 71 through the seal 30a, and is erected from the outer peripheral end of the lid portion 30 so that the jack member 3 is formed in a flange shape. And a cylindrical partition wall 31 slidably in contact with each other via a seal 70 a, and the jack chamber J is formed between the outer peripheral portion of the bottom portion 70 of the connecting member 7 and the lid portion 30 of the jack member 3.

  Therefore, the jack chamber J can be easily expanded and contracted, and the jack chamber J and the other chamber B can be easily partitioned.

  Further, in the present embodiment, a rubber bush 24 is provided between the tip of the tip member 21 (the lower end in FIG. 2) and the bottom 70 of the connecting member 7, and a hole 73 that communicates with the axial hole L20 by this rubber bush 24. Therefore, the jack fluid can be filled into the jack chamber J and the jack flow path L by inserting the needle into the rubber bush 24 from the hole 73, and the work of filling the jack fluid is facilitated.

  Further, in the present embodiment, a plug member 8 that is inserted in the jack flow path L so as to be able to advance and retreat is provided at the opening on the anti-jack chamber side (upper side in FIG. 1) of the jack flow path L. The member 8 is driven by the adjusting member 5 to supply and discharge the jack fluid to and from the jack chamber J, and the configuration for supplying and discharging the jack fluid into the jack chamber J can be simplified.

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

  For example, in the above embodiment, the shock absorber D according to the present invention is mounted on the front fork. However, even if the shock absorber D is mounted on a rear cushion unit that suspends the rear wheel of a motorcycle, It may be installed.

  The front fork on which the shock absorber D is mounted in the above embodiment is an inverted front fork in which the outer tube T1 is connected to the vehicle body side and the inner tube T2 is connected to the wheel side. May be connected to the wheel side, and the inner tube T2 may be an upright front fork connected to the wheel side.

  Further, the front fork in the above embodiment includes a cylinder 6 standing at the axial center portion of the inner tube T2, a piston rod 2 fixed to the outer tube T1 side and inserted in the cylinder 6 so as to be movable in the axial direction, Although the shock absorber D including the piston 1 held by the piston rod 2 is provided, the cylinder 6 may be eliminated and the piston 1 may be in direct sliding contact with the inner peripheral surface of the inner tube T2.

  In the above embodiment, the working fluid is made of oil, but the working fluid may be made of another liquid such as water or a gas such as an inert gas.

  In the above embodiment, the jack fluid is made of oil. However, the jack fluid may be made of other liquid such as water, or may be made of a gas such as an inert gas. A fluid may be used.

  In the above-described embodiment, the adjusting member 5 adjusts the high-speed damping force on the extension side of the front fork. However, the valve stopper 12 is replaced with a valve presser, and the tip of the valve presser is always the one-side leaf valve 11. If the contact is made, the valve opening pressure of the one-side leaf valve 11 can be adjusted.

  Further, when the one side leaf valve 11 and the spacer 13 are slidably contacted with the outer periphery of the spacer 14 together with the valve stopper 12 to be movable in the axial direction, and when the piston speed reaches the extension side high speed region when the front fork is extended, The one-side leaf valve 11, the spacer 13 and the valve stopper 12 may be lifted downward in FIG.

  The shock absorber D according to the above embodiment is a one-rod type shock absorber, and the other side (the lower side in FIGS. 1 and 2) of the piston rod 2 projects into the other chamber B and the other chamber B. It is good also as a double rod type shock absorber penetrating through.

  In this case, when the front fork is compressed, the damping force due to the resistance of the working fluid passing through the other side flow passage 10a, that is, the compression side damping force may be adjusted using the above configuration.

  In addition, the valve disk in the above embodiment is the piston 1, but may be a base member having a flow path that communicates the other chamber B and the reservoir R. In this case, the shaft member is a base rod that supports the base member.

  In the above embodiment, a hole 73 is provided in the bottom 70 of the connecting member 7, and the hole 73 is closed with the rubber bush 24. However, any structure that forms the jack chamber J or the jack flow path L, for example, the cylindrical member 20 or the tip member 21 that constitutes the piston rod 2 or the jack member 3 is provided with a hole, and the rubber bush 24 In this case, the filling operation of the jack fluid can be facilitated.

  Further, in the above-described embodiment, the anti-jack chamber side (the upper side in FIG. 1) of the jack flow path L is closed by the plug member 8 that can move back and forth in the jack flow path L. This plug member 8 Is driven by the adjusting member 5, thereby supplying and discharging the jack fluid into the jack chamber J. However, the configuration in which the jack fluid is supplied to and discharged from the jack chamber J is not limited to the above, and the jack fluid may be supplied to and discharged from the jack chamber J using a pump or the like connected to the jack flow path L.

  In the above embodiment, the urging spring 4 is interposed between the valve stopper 12 and the jack member 3. However, the present invention is not limited to this. For example, a pair of free contacts that are in sliding contact with the inner periphery of the cylindrical member 20. Pistons may be provided, and the urging spring 4 may be provided between these free pistons. Further, an air chamber may be formed between the pair of free pistons, and the air chamber may function as the biasing spring 4.

A One chamber B Other chamber C1 Cap member C2 Oil seal C3 Dust seal D, D1 Shock absorber J Jack chamber L Flow path for jack L1 Flow path in cylindrical member L2 Flow path in tip member O Liquid level S Suspension spring T Suspension device main body T1 Outer tube T2 Inner tube V1 Extension side damping valve V2 Pressure side check valve 1 Piston 2 as valve disc 2 Piston rod 3 as shaft member Jack member 4,92 Biasing spring 5 Adjustment member 6 Cylinder 7 Connection member 8 Plug members 8a, 9a, 9b, 15, 30a, 70a Seal 10 One-side flow path 10a Other-side flow path 11 One-side leaf valve 11a Other-side leaf valve 12, 12a Valve stopper 13, 13a Spacer 14 Spacer 20 Cylindrical member 21 Tip member 23 Nut 24 Rubber bush 30 Lid 31 Bulkhead 51 Lock nut 60 Rod Id 60a bearing member 61 fully extended spring 70 bottom 71 the cylindrical portion 72 through hole 73 hole 74 gap 90 sheet member 91 the valve presser 93 push rod

Claims (7)

A valve disc that divides into one chamber and the other chamber; a flow passage formed in the valve disc that communicates the one chamber with the other chamber; and a layer stacked on the other chamber side of the valve disc. In a shock absorber comprising a leaf valve that closes the outlet in an openable and closable manner, and a shaft member that penetrates the valve disk and the axial center of the leaf valve, and one side penetrates the one chamber and the other side projects into the other chamber.
A jack chamber formed in the other chamber, a jack member movable in the axial direction as the jack chamber expands and contracts, a jack passage formed in the shaft member and always communicating with the jack chamber, An adjusting member attached to one side of the shaft member and supplying / discharging jack fluid to / from the jack chamber via the jack flow path, and the leaf valve is attached to the valve disc side by movement of the jack member. A shock absorber characterized by adjusting a spring force of a biasing spring.   The shock absorber according to claim 1, wherein the jack chamber is formed between a connecting member that covers the other end of the piston rod disposed in the other chamber and the jack member. The connecting member includes a bottom portion and a cylindrical portion standing on the bottom portion, and is formed into a bottomed cylindrical shape, and an outer peripheral portion of the bottom portion protrudes from the cylindrical portion and is formed into a flange shape,
The jack member includes a lid portion that is in sliding contact with the outer peripheral surface of the cylindrical portion via a seal, and a cylindrical partition wall that is suspended from the outer peripheral end of the lid portion and is in sliding contact with the outer peripheral surface of the bottom portion via the seal. With
The shock absorber according to claim 2, wherein the jack chamber is formed between an outer peripheral portion of the bottom portion of the connecting member and the lid portion of the jack member.   A valve stopper is provided that is movably mounted along the shaft member and that contacts the leaf valve when the leaf valve is deflected by a predetermined amount, and the biasing spring is disposed between the valve stopper and the jack member. The shock absorber according to any one of claims 1 to 3, wherein the shock absorber is interposed.   The anti-jack chamber side of the jack flow path is closed with a plug member that can be advanced and retracted into the jack flow path, and the plug member is driven by the adjusting member. 4. The shock absorber according to any one of 4.   6. The shaft member, the jack member, or the connecting member that forms the jack chamber or the jack flow path therein, a hole is provided, and the hole is closed with a rubber bush. The shock absorber in any one. A cylinder, a piston rod which is inserted into the cylinder so as to be movable in the axial direction, and a piston which is held at the tip of the piston rod and slidably contacts the inner peripheral surface of the cylinder, the shaft member being the piston rod And the valve disc is the piston,
The shock absorber according to any one of claims 1 to 6, wherein the cylinder is partitioned by the piston into the one chamber and the other chamber.

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