JPH0914325A - Hydraulic shock absorber damping force adjustment mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] In a damping force adjusting mechanism of a hydraulic shock absorber, damage to a throttle portion that generates damping force is prevented and adjustment is facilitated. [Structure] When a knob 89 is rotated, a cam 86 is rotated, and the rotation of the cam 86 is combined with the needle 56V so as to move forward and backward with respect to the oil passage 55, which is a throttle portion.
When the pin 111 inserted in 7 hits the adjuster 88, the rotation of the knob 89 is restricted so that the needle 56V does not excessively enter the oil passage 55.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic shock absorber incorporated in a suspension device of a vehicle such as a motorcycle or an automobile, and more particularly to a damping force adjusting mechanism for adjusting the damping force of the hydraulic shock absorber.

[0002]

2. Description of the Related Art The above suspension device is usually composed of a combination of a cushion spring for absorbing irregularities on the road surface and a shock absorber for damping the elastic force of the cushion spring. The shock absorber is generally a hydraulic shock absorber that obtains a damping force by utilizing the flow resistance of the hydraulic oil contained in the cylinder. Japanese Patent Publication No. 5-26050 discloses an example of the hydraulic shock absorber. In this hydraulic shock absorber, a piston supported by a rod is slidably inserted into the cylinder to divide the interior of the cylinder into two chambers in the axial direction.
As the volume of the two chambers changes due to the relative movement of the cylinder and the rod in the axial direction, the hydraulic oil sealed in the two chambers moves back and forth through the throttle portion (orifice) formed between the piston and the rod. Due to the flow resistance at the time, a damping force is obtained.

[0003]

In the hydraulic shock absorber disclosed in the above publication, the needle slidably inserted in the axial center of the rod is advanced and retracted by rotating the nut provided at the end thereof. As a result, the damping force can be adjusted by changing the opening area of the narrowed portion by the conical tip surface of the needle. In order to maximize the damping force, the needle tip surface is brought into contact with the opening edge of the throttle portion to fully close the throttle portion, whereby the amount of advance / retreat of the rod into the cylinder is restricted to the maximum. When the damping force is maximized in this way, the tip end surface of the needle comes into contact with the opening edge forming the narrowed portion as described above. Therefore, while the adjustment of the damping force is repeated, the tip surface of the needle or the opening edge of the throttle portion may be worn, and it may not be possible to obtain a prescribed damping force according to the amount of rotation of the nut. In addition, if the nut is excessively turned, the tip surface of the needle may be pressed against the opening edge of the narrowed portion. Therefore, there is also a disadvantage that a delicate operation is required for adjustment especially when the nut is fully closed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a damping force adjusting mechanism for a hydraulic shock absorber in which damage to the throttle portion is prevented and adjustment is easy.

[0005]

The present invention has been made to achieve the above object, and a damping force adjusting mechanism for a hydraulic shock absorber according to claim 1 is provided in a plurality of parts inside the shock absorber. Damping mechanism for a hydraulic shock absorber for adjusting the damping force by advancing and retracting the throttling member with respect to the throttling portion that communicates the respective oil chambers with each other to change the flow resistance of the hydraulic oil passing through the throttling portion. The stator fixed to the constituent member of the shock absorber, the manipulator rotatably mounted on the stator, and the stator arranged so as to face the stator and integrally rotated together with the manipulator. A diaphragm that moves the diaphragm member forward and backward with respect to the diaphragm part by movement, and a plurality of pin insertion holes are provided on either one of the facing surfaces of the stator and the rotor.
The pins are formed concentrically and equidistantly about the rotation axis of the rotator, and pins are inserted into at least one of them, and the other is formed with the rotation of the rotator. It is characterized in that a stopper portion is formed which abuts the pin and regulates the movement of the diaphragm member.

A damping force adjusting mechanism for a hydraulic shock absorber according to a second aspect of the present invention is the damping force adjusting mechanism for a hydraulic shock absorber according to the first aspect, wherein the stator, the operator and the rotator are provided. Is assembled so that it can be disassembled, and in the assembled state, the pin inserted into the pin insertion hole is retained in the pin insertion hole by an operator.

A damping force adjusting mechanism for a hydraulic shock absorber according to a third aspect of the present invention is the damping force adjusting mechanism for a hydraulic shock absorber according to the first or second aspect, wherein the stator or the rotator is provided with: It is characterized in that the protrusion, which is biased toward the pin insertion hole side by the biasing member, is provided so that it can be inserted into and removed from the pin insertion hole as the rotary member rotates.

[0008]

According to the damping force adjusting mechanism of the hydraulic shock absorber according to the first aspect of the present invention, when the operator is rotated, the rotor is also rotated, and the throttle member is moved forward and backward with respect to the throttle portion. The damping degree is adjusted by adjusting the degree of throttling of the throttling portion. As the rotator rotates, the pin comes into contact with the stopper portion and further rotation is restricted, so damage to the throttle portion is prevented in advance. Further, the adjustment range of the operator can be arbitrarily set depending on which of the plurality of pin insertion holes the pin is inserted.

According to the damping force adjusting mechanism of the hydraulic shock absorber according to the second aspect of the present invention, after assembling, the stator, the operator and the rotator are disassembled and the pin is inserted into another pin insertion hole. It can be reassembled and reassembled, and therefore, the adjustment range of the operator can be easily set arbitrarily.

According to the damping force adjusting mechanism of the hydraulic shock absorber according to the third aspect of the present invention, when the operating element is rotated, the projection element is repeatedly inserted into and removed from the pin insertion hole, and a click sound is generated each time. As it occurs, resistance occurs. Therefore, the damping force can be adjusted stepwise with moderation, and the pin insertion hole can be effectively used.

[0011]

【Example】

A-1. Configuration of One Embodiment One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a hydraulic shock absorber 1 for an automobile according to an embodiment of the present invention.
Is a side view and FIG. 2 is a sectional view thereof. In these drawings, reference numeral 2 is a cylinder, 3 is a piston fitted in the cylinder 2, and 4 is a rod which is fixed integrally with the piston 3 and expands and contracts with respect to the cylinder 2. In this hydraulic shock absorber 1, the cylinder 2 is connected to the lower spring and the rod 4 is connected to the upper spring. A spring seat 5 is mounted on the outer periphery of the upper end of the cylinder 2 to receive the lower end of a cushion spring (not shown) that is bridged between the upper part of the spring and the upper part of the spring.

The cylinder 2 has a triple structure composed of an outer cylinder 6, a middle cylinder 7 and an inner cylinder 8. As shown in FIG. 3, the upper openings of the middle cylinder 7 and the inner cylinder 8 are covered with a rod guide 10 press-fitted into the upper openings of the outer cylinder 6. A circlip 11 is fitted on the inner circumference of the upper opening of the outer cylinder 6, and between the circlip 11 and the rod guide 10, a washer 12, a rubber ring 13 in a compressed state and this rubber ring 13 are seized. A metal plate 14 that is integrally attached by processing is interposed. As shown in FIG. 4, a base housing (constituent member) 15 is fitted into the lower end opening of the outer cylinder 6, the middle cylinder 7 and the inner cylinder 8 are inserted into the outer cylinder 6, and the lower end portion thereof is a base valve 16. Is engaged with the outer peripheral portion of the.

The middle cylinder 7 and the inner cylinder 8 are sandwiched between the base valve 16 and the rod guide 10 and supported by the elastic force of the rubber ring 13. Rubber ring 13 is cylinder 2
The inside and outside are sealed, and the elasticity absorbs variations in dimensional accuracy in the axial direction of the inner cylinder 8, the middle cylinder 7, the rod guide 10 and the like, and shocks. Besides this, washer 1
The fixing force can be adjusted by changing the thickness of 2 to make the elastic force of the rubber ring 13 harder or softer.

As shown in FIG. 3, the piston 3 is constructed by mounting a piston ring 20 on the outer circumference of a piston body 19, and the piston ring 20 slides liquid-tightly on the inner peripheral wall surface of the inner cylinder 8. It is fitted in the inner cylinder 8 so as to be movable. Due to the piston 3, the inside of the inner cylinder 8 has an upper oil chamber 21.
And a lower oil chamber 22. The rod 4 penetrates the rod guide 10, and a piston body 19 is fixed to a lower end portion of the rod guide 10 by being sandwiched between a nut 23 and a washer 24. A bearing 25 is mounted on the rod guide 10, and a seal 26 is mounted on the outer side. A cap 27 is placed on the upper opening of the outer cylinder 6. A bypass oil passage 30 having a narrow gap is formed between the inner cylinder 8 and the middle cylinder 7, and a reservoir chamber 31 is formed between the middle cylinder 7 and the outer cylinder 6. The upper oil chamber 21 and the bypass oil passage 30 communicate with each other through an oil hole 32 formed in the upper end of the inner cylinder 8.

Above the piston 3 of the rod 4,
A collar 33 having a predetermined length is provided on the exterior, and a washer 34 and a rubber ring 35 are provided on the exterior. A washer 36 is fitted between the piston body 19 and the collar 33. The extension stroke of the piston 3 in which the rod 4 withdraws from the cylinder 2 is made a stroke end when the washer 36 hits the collar 33, the washer 34, and the rubber ring 35, and further upward movement is restricted. At the end of that stroke, rubber ring 3
5 absorbs the shock. The stroke end at the time of extension can be selected by the number and length of the collars 33.
2 and 3, the left side shows the case where there is one collar 33, and the right side shows the case where there are two collars 33.

As shown in FIG. 3, the piston body 19 of the piston 3 has a plurality of first oil passages 41 and second oil passages 42 that connect the upper oil chamber 21 and the lower oil chamber 22 to each other. They are formed at equal intervals in the direction and alternately. First oil passage 41
Is opened and closed by a check valve 41V which is a plate valve mounted on the lower surface side of the piston 3. The check valve 41V opens the first oil passage 41 during the expansion stroke of the piston 3 and allows only the working oil L to flow from the upper oil chamber 21 to the lower oil chamber 22. The second oil passage 42 is a check valve 42V which is a plate valve mounted on the upper surface side of the piston 3.
Is opened and closed. The check valve 42V opens the second oil passage 42 during the compression stroke of the piston 3 to open the lower oil chamber 22.
Only allows the hydraulic oil L to flow from the upper part to the upper oil chamber 21.
Although the upper opening of the first oil passage 41 is covered with the check valve 42V, the first oil passage 41 is provided on the upper surface of the piston 3.
The oil passage is secured so that the check valve 42V is not affected. Further, the lower opening of the second oil passage 42 is
It opens to the side avoiding the check valve 41V.

Next, the base valve 16 will be described with reference to FIGS. The base valve 16 has a valve body 50 as a main component. A convex portion 51 is formed in the center of the upper surface of the valve body 50, and a groove portion 52 is formed around the convex portion 51. By the groove portion 52, the groove portion 52
Annular projections 53 and 54 are formed on the outer peripheral side and the inner peripheral side, respectively. An oil passage (throttle portion) 55 is formed at the axial center of the base valve 16 and communicates vertically with the convex portion 51. The area of the lower end opening of the oil passage 55 corresponds to the needle (throttle member) 5 attached to the base housing 15.
It is adjusted by 6V. Further, in the valve body 50, an oil passage 57 and an oil passage 5 that connect the lower oil chamber 22, the reservoir chamber 31, the oil passage 55, and the bypass oil passage 30 to each other.
8 are formed respectively. The oil passages 57 are provided at a plurality of locations (in this case, four locations) equally divided into the circumference so that a large flow passage area can be obtained, and communicate with the groove portion 52 to the outer peripheral side of the lower surface. Two oil passages 58 are formed in a straight line between the oil passages 57.

On the convex portion 51 of the valve body 50, there is a shim 59 that abuts against the convex strip 54 on the inner peripheral side, a washer 60 on the shim 59, and a circlip 6 fitted on the upper end of the convex portion 51.
A wave spring 63 is mounted so as to be sandwiched between the first and the washer 62 below the first spring. A check valve 64V, which is a plate valve that opens and closes the oil passage 57, is attached to the lower washer 60 and the ridge 53 on the outer peripheral side. A relatively large gap is provided between the inner circumference of the check valve 64V and the outer circumference of the shim 59, and the plate thickness of the shim 59 is thinner than the plate thickness of the check valve 64V. A slight gap is provided between the shim 59 and the shim 59.

The check valve 64V is positioned in the center of the valve body 50 by being guided by the inner side surface of a guide protrusion 65 provided outside the upper opening of the oil passage 57. Then, normally, by the elastic force of the wave spring 63, the lower surface on the outer peripheral side is engaged with the convex strip 53 on the outer peripheral side, and the upper surface on the inner peripheral side is engaged with the washer 60, respectively, and the groove portion 52 is
To close the upper opening of the oil passage 57. According to this check valve 64V, during the compression stroke of the piston 3,
When the pressure in the lower oil chamber 22 rises and the inner peripheral side of the check valve 64V is elastically deformed downward beyond the gap between the washer 60 and the shim 59, the oil passage 57 opens, and the hydraulic oil from the lower oil chamber 22 to the reservoir chamber 31 is opened. Only the distribution of L is allowed.

During the expansion stroke of the piston 3, the wave spring 63 is compressed to check the check valve 64V.
The whole floats above the groove portion 52, the oil passage 57 opens, and the hydraulic oil L flows from the reservoir chamber 31 into the lower oil chamber 22. The gap between the washer 60 and the shim 59 is
When the pressure in the lower oil chamber 22 during the compression stroke of the piston 3 is small and the displacement amount of the check valve 64V is smaller than the gap, that is, when the descending speed of the piston 3 is slow,
The check valve 64V is prevented from opening so that the compression-side damping force increases with respect to the descending speed of the piston 3. This is for suppressing posture changes (mainly rolling and pitching) required for vehicles such as automobiles. The characteristics of the compression-side damping force can be easily changed by simply selecting the plate thickness of the shim 59.

The inner cylinder 8, that is, the upper oil chamber 21, the lower oil chamber 22, and the bypass oil passage 30 are filled with hydraulic oil L, and the hydraulic oil L reaches the middle of the reservoir chamber 31. An upper space of the reservoir chamber 31 where the hydraulic oil L does not enter is a gas chamber 70, and in order to suppress expansion of air mixed in the hydraulic oil L, the gas chamber 70 is pressurized to a certain level higher than atmospheric pressure. Nitrogen gas is enclosed.

As shown in FIG. 3, a circlip groove 71, which is a peripheral groove, is formed on the outer peripheral surface of the upper portion of the outer cylinder 6 of the cylinder 2, and the spring seat 5 is attached to the circlip 72 fitted therein. Engaged. Spring seat 5
Is provided with a collar-shaped seat portion 74 integrally on the outer periphery of the ring 73, and the seat portion 74 is formed in a spiral shape so as to match the lower end surface of the cushion spring. Circlip engaging grooves 75 and 76 are formed on the inner peripheral edges of the ring 73 on one end side and the other end side, respectively. In this case, the engagement groove 75 on one end side is formed deeper than the center of the ring 73 in the axial direction, and the engagement groove 76 on the other end side is formed.
Is shallow enough to engage the circlip 72. In the case of the illustrated example, the shallow engagement groove 76 is engaged with the circlip 72 and the ring 73 is attached to the outer cylinder 6. By changing the mounting direction of the spring seat 5 and selecting the engagement grooves 75 and 76 to be engaged with the circlip 72, cushion springs of different lengths can be accommodated. In other words, the deep engagement groove 75
When engaged with 2, the seat portion 74 moves downwards to accommodate a longer cushion spring than in the case of the shallow engagement groove 76.

In the spring seat 5, the axial position of the seat portion 74 can be changed by the difference in the depth of the engaging grooves 75 and 76 to be engaged with the circlip 72. In addition to this, the seat surface shape for receiving the cushion spring of the seat portion 74 may be different on the front and back sides. According to this, one spring seat can handle two models, and in manufacturing, it is possible to reduce the number of parts and the cost accordingly.

A damping force adjusting mechanism 80 for adjusting the damping force (hardness) of the hydraulic shock absorber 1 by advancing and retracting the needle 56V with respect to the oil passage 55 is provided in the base housing 15. Has been. As shown in FIGS. 4 and 8, the damping force adjusting mechanism 80 is mounted in a mounting hole 81 opened from the side of the base housing 15. The needle 56V is slidably fitted in a needle chamber 82 formed in the base housing 15. The needle chamber 82 has an upper end opening in the oil passage 55 and a lower end opening in the mounting hole 81.
The conical tip of V penetrates into the oil passage 55,
The lower end portion formed in a spherical shape is exposed in the mounting hole 81. The needle 56V receives a pressure from the hydraulic oil L receiving the pressure of the pressurized gas and is always urged downward.

The mounting hole 81 has a small-diameter hole 83,
The medium-diameter hole 84 and the large-diameter hole 85 are circular holes that are coaxially formed and gradually expand in diameter. The damping force adjusting mechanism 80 includes a cam 86 rotatably fitted over the small diameter hole 83 and the medium diameter hole 84, a cap (stator) 87 fixed in the large diameter hole 85, and the inside of the cap 87. The adjuster (rotator) 88 is rotatably fitted into the adjuster 88 and the knob (operator) 89 is screwed to the adjuster 88 from the outside. These are assembled in the base housing 15 so as to be disassembled.

The cam 86 includes a cam portion 90 having a cam surface 90a and a disc-shaped shaft portion 9 fitted in a medium diameter hole 84.
1 and a connecting convex portion 92 which is a connecting portion with the adjuster 88. In the cam 86, the shaft portion 91 is rotatably fitted in the small diameter hole 83 and the medium diameter hole 84 with the medium diameter hole 84 as a bearing. The cam portion 90 rotates in the small diameter hole 83, and the lower end surface of the needle 56V is always in contact with the cam surface 90a. As shown in FIG. 9, the cam profile of the cam portion 90 is such that a base portion 93 having the smallest diameter is formed with an enlarged diameter portion 94 whose effective radius gradually increases, and a boundary between the largest diameter enlarged portion 95 and the base portion 93 is formed. An end surface 96 is formed at the end. The connecting convex portion 92 is formed as a circular convex portion having a notch in cross section. The cap 87 is formed by integrally molding a top plate portion 97 and a cylindrical portion 98, and the cylindrical portion 98 is press-fitted and fixed in the large diameter hole 85.

The adjuster 88 has a cap 87 on the outer peripheral surface.
Is rotatably fitted into the inside of the cap 87 so as to be in sliding contact with the inner peripheral surface of the. A fitting hole 99 having a circular cross section with a cutout is formed on the inner end surface of the adjuster 88, and the connecting convex portion 92 is fitted into the fitting hole 99. Since the eccentric connecting convex portion 92 is fitted in the fitting hole 99, the adjuster 88 is rotated by the cam 86.
It is transmitted to. A small space 100 is formed between the connecting convex portion 92 and the fitting hole 99.

At the center of the outer end surface of the adjuster 88,
A convex portion 101 having a circular cross section with a notch is formed. The convex portion 101 is fitted into the concave portion 102 of the knob 89 through a top plate portion 97 of the cap 87 and a through hole 97a formed coaxially with the shaft portion 91 of the cam 86. As shown in FIG. 11, a knob 89 is fixed to the convex portion 101 with a screw 103. In this knob 89, a surrounding collar portion 89a covers the outer periphery of the cap 87, and a dust seal 104 for preventing intrusion of water and dust is interposed between them. When the knob 89 is rotated, the adjuster 88 and the cam 86 are integrally rotated.

As shown in FIGS. 8 and 10, the top plate portion 9 of the cap 87 is provided around the outer end surface of the adjuster 88.
An annular notch 105 is formed so as to leave a space between the notch 7 and the groove 7. The notch 105 is not formed over the entire circumference and is formed with a part left, and the remaining part is formed as a fan-shaped stopper portion 106. This stopper 10
6 is formed with a ball hole 107 opening to the outer end surface.

A plurality of pin insertion holes 110 are formed around the through hole 97a of the top plate portion 97 of the cap 87.
7a are formed concentrically and at equal pitches. These pin insertion holes 110 are formed at positions that match the ball holes 107 of the adjuster 88 that rotates with the knob 89. The pin 111 is inserted in one of the pin insertion holes 110. This pin 1
Reference numeral 11 projects into the notch 105 and cannot be removed by the knob 89. A ball (protrusion) 113 biased by a coil spring (biasing member) 112 is fitted into the ball hole 107 of the adjuster 88,
A part of the ball 113 fits into the pin insertion hole 110 of the cap 87.

According to the damping force adjusting mechanism 80, the knob 8
When the adjuster 88 rotates together with 9, the ball 113
However, while being urged by the coil spring 112, it is pressed by the top plate portion 97 of the cap 87 between the pin insertion hole 110 and the pin insertion hole 110. The part protrudes and fits into the pin insertion hole 110. Therefore, the knob 89
As the ball 113 is rotated, a clicking sound such as "clicking" is generated every time the ball 113 jumps into each pin insertion hole 110, and resistance is generated when the ball 113 is pulled out from the pin insertion hole 110. That is, the plurality of pin insertion holes 110 and the balls 113 fitted in the pin insertion holes 110.
The click mechanism 114 is configured by the above. By using the click mechanism 114, the damping force can be adjusted stepwise by turning the knob 89.

A-2. Operation of One Embodiment The above is the hydraulic shock absorber 1 of the present embodiment. Next, the operation of the hydraulic shock absorber 1 will be described. (1) Action during extension stroke When the cushion spring extends, the piston 3 rises in the inner cylinder 8 together with the rod 4 extending along with it. During this extension stroke, the upper oil chamber 21 is compressed to a high pressure,
The lower oil chamber 22 expands to a negative pressure, and the hydraulic oil L flows as follows to compensate for this pressure change.

A. Part of the hydraulic oil L in the upper oil chamber 21
The oil flows from the oil hole 32 of the inner cylinder 8 into the bypass oil passage 30 and flows downward, and then flows from the oil passage 58 of the base valve 16 through the oil passage 55 into the lower oil chamber 22. When passing through the oil passage 55, flow resistance is received from the needle 56V. B. A part of the hydraulic oil L in the upper oil chamber 21 flows into the lower oil chamber 22 through the first oil passage 41 of the piston 3 while opening the check valve 41V. Check valve 41V
Distribution resistance due to. C. The lower pressure of the lower oil chamber 22 causes the check valve 64V of the base valve 16 to push up the wave spring 63, and the hydraulic oil L in the reservoir chamber 31 flows into the lower oil chamber 22 through the oil passage 57. During the extension process, a damping force is generated by receiving the flow resistance at the two points a and b.

(2) Action during compression stroke When the cushion spring contracts, the piston 3 moves down in the inner cylinder 8 together with the rod 4 which contracts accordingly. During this compression stroke, the lower oil chamber 22 is compressed to a high pressure and the upper oil chamber 21 is expanded to a low pressure, and the hydraulic oil L circulates as follows to compensate for this pressure change.

A. Part of the hydraulic oil L in the lower oil chamber 22
After passing through the oil passage 55 and the oil passage 58 of the base valve 16 and flowing into the bypass oil passage 30 and flowing upward, the oil hole 32 of the inner cylinder 8
Flows into the upper oil chamber 21. When passing through the oil passage 55,
Flow resistance is received from the needle 56V. B. A part of the hydraulic oil L in the lower oil chamber 22 pushes down the inner peripheral side of the check valve 64V of the base valve 16 and flows into the reservoir chamber 31 from the groove 52 through the oil passage 57. Flow resistance is received by the check valve 64V. C. A part of the hydraulic oil L in the lower oil chamber 22 flows through the oil passage 42 of the piston 3 into the upper oil chamber 21 while opening the check valve 42V. Flow resistance is received by the check valve 42V. During the compression stroke, a damping force is generated by receiving the flow resistance at the above three points (a), (b) and (c).

(3) Operation of the damping force adjusting mechanism 80 When the knob 89 is turned to the right, the damping force is improved: hard, and to the left, the damping force is decreased: soft. As the knob 89 is turned to the right, the effective radius of the cam portion 90 expands,
The cam surface 90a of 0 pushes up the needle 56V while slidingly contacting the lower end surface of the needle 56V. Then, the opening area of the oil passage 55 is reduced, the damping force is increased, and the setting becomes hard. When the effective radius of the cam portion 90 is maximized, the amount of rise of the needle 56V is also maximized and becomes the hardest. At this time, the stopper portion 106 of the adjuster 88
If the insertion position of the pin 111 is set so that the pin will hit the pin 111 and further rotation will be restricted, the knob 8
The maximum damping force is obtained when turning 9 to the right and stopping.

When the knob 89 is turned counterclockwise, the needle 56V receiving the pressure of the hydraulic oil L descends as the effective radius of the cam portion 90 decreases. Needle 56V
When is lowered, the opening area of the oil passage 55 is enlarged, and as a result, the damping force is reduced and the setting becomes soft. When the knob 89 is turned counterclockwise, the stopper portion 106 of the adjuster 88 hits the pin 111 and further rotation is restricted, and the damping force is minimized at that time.

A-3. Effects of One Embodiment (1) Effects of Damping Force Adjusting Mechanism 80 According to the damping force adjusting mechanism 80 of the above embodiment, when the knob 89 is rotated, the cam 86 is rotated via the adjuster 88 and the needle 56V is moved. Moves back and forth with respect to oil passage 55, and oil passage 5
The damping force is adjusted by adjusting the aperture degree of No. 5. With the rotation of the adjuster 88, the pin 111 inserted into any of the pin insertion holes 110 comes into contact with the stopper portion 106 and further rotation is restricted, so that the opening edge of the needle 56V or the oil passage 55 is restricted. The damage of the can be prevented. Also,
The rotation range of the knob 89 can be arbitrarily set depending on which of the plurality of pin insertion holes 110 the pin 111 is inserted.
In that case, the cam 86, the cap 87, the adjuster 8
Since the 8, knob 89 and the like can be disassembled, these may be disassembled and the pin 111 may be reinserted into the other pin insertion hole 110 and reassembled.

Also, the click mechanism 114 causes the knob 8
When the ball 9 is rotated, the ball 113 is repeatedly inserted into and removed from the pin insertion hole 110, and a click sound is generated and resistance is generated each time. Therefore, the damping force can be adjusted stepwise with moderation, and the pin insertion hole 110 can be effectively used.

(2) Effect of Damping Force Generating Action The throttle part for obtaining the damping force on the extension side is the check valve 41V,
The throttles are set at two positions of the needle 56V, and the throttle portions for obtaining the compression side damping force are set at three positions of the check valves 42V and 64V and the needle 56V. As described above, in any of the cases, the throttle portions are set at a plurality of positions, so that a stable damping force can be obtained, and the adjustment range of the damping force is widened to allow fine adjustment. In particular, on the compression side, there are as many as three throttle portions, which is excellent in stability of damping force, and the degree of throttle can be adjusted more finely. Further, the degree of reduction of the oil passage 55 by the needle 56V can be adjusted from the outside by the damping force adjusting mechanism 80 without requiring the processing of the rod 4, so that the rod 4 can be manufactured without being affected by the thickness thereof.

Since both ends of the cylinder 2 are sealed by the rod guide 10 on the upper oil chamber 21 side and by the base housing 15 and the base valve 16 on the lower oil chamber 22 side, respectively, the sealing performance is improved. Therefore, the hydraulic oil L does not leak even when operated under high pressure.

Further, during the extension stroke of the piston 3, the hydraulic oil L in the reservoir chamber 31 pressurized by the gas in the gas chamber 70 between the outer cylinder 6 and the middle cylinder 7 passes through the oil passage 57 and the lower oil. Since it flows into the chamber 22, the gas mixing ratio in the hydraulic oil L flowing into the lower oil chamber 22 is reduced, and therefore the damping force is stabilized.

B-1. Modification 1 of Damping Force Adjustment Mechanism 80 FIG. 12 shows a modification of the damping force adjustment mechanism 80.
In this modification, a mounting hole 81 is coaxially formed in the lower end surface of the base housing 15, and the cap 87, the adjuster 88, the knob 89 and the like are similarly mounted in the mounting hole 81. On the other hand, the lower end of the needle 56V is rotatably screwed to the base housing 15, and
Connecting projection 92 having a circular cross section with a cutout on the lower end surface of 6V
Is fitted into the fitting hole 99 of the adjuster 88. According to the damping force adjusting mechanism 80, the rotation of the knob 89 is directly transmitted to the needle 56V, and the needle 56V moves up and down while rotating around the axis. That is, if the knob 89 is turned to the right, the needle 56V is raised, and if it is turned to the left, it is lowered.

B-2. Modified Example 2 of Damping Force Adjusting Mechanism 80 Further, the click mechanism 114 of the above-described embodiment has a plurality of pin insertion holes 110 provided in the fixed side cap 87,
Although it is composed of the ball 113 provided on the movable-side adjuster 88, these may be composed in reverse. That is, as shown in FIG. 13, a ball hole 107 is formed inside the cap 87, and the ball 113 urged by the coil spring 112 is housed in the ball hole 107. Further, a plurality of pin insertion holes 110 are formed on the outer surface of the adjuster 88, and the pin 111 is inserted into one of these pin insertion holes 110. A stopper portion that restricts the rotation of the knob 89 by hitting the pin 111 is provided in the fixed cap 87, and the pin insertion hole 110 that rotates with respect to the fixed ball 113.
Is a structure that fits. The ball 1 in this case
The contact surface of the coil spring 13 with the coil spring 112 is flat.

The damping force adjusting mechanism 80 of the above embodiment
Is configured to move the needle 56V forward and backward with respect to the oil passage 55, but the present invention is not limited to such a form of the throttle portion, and any means may be used for adjusting the degree of throttle of the throttle portion. Good. In addition to the hydraulic shock absorber for automobiles, of course, motorcycles and other vehicles,
Alternatively, it can be applied to various hydraulic shock absorbers attached to other than vehicles.

[0046]

According to the damping force adjusting mechanism of the hydraulic shock absorber according to the first aspect of the present invention, the pin abuts on the stopper portion as the rotator rotates, and further rotation is restricted. As a result, it is possible to prevent damage to the throttle portion and to set the adjustment range of the operator arbitrarily depending on which of the plurality of pin insertion holes the pin is inserted. According to the damping force adjusting mechanism of the hydraulic shock absorber according to the second aspect of the present invention, after the assembling, the stator, the operator and the rotator are disassembled and the pin is reinserted into another pin insertion hole. It can be reassembled, and therefore, the adjustment range of the operator can be easily set arbitrarily. According to the damping force adjusting mechanism of the hydraulic shock absorber according to the third aspect of the present invention, the damping force can be adjusted stepwise with moderation, and the pin insertion hole can be effectively used.

[Brief description of the drawings]

FIG. 1 is a side view of a hydraulic shock absorber according to an embodiment of the present invention.

FIG. 2 is a sectional side view of the same.

FIG. 3 is a side sectional view of the upper end portion.

FIG. 4 is a side sectional view of the lower end portion.

FIG. 5 is a side view of the base valve.

FIG. 6 is a plan view of the same.

7 is a sectional view taken along the line VII-VII of FIG.

FIG. 8 is a side sectional view showing a damping force adjusting mechanism.

FIG. 9 is a front view of a cam portion.

FIG. 10 is a front view showing a click mechanism.

FIG. 11 is a front view of the knob.

FIG. 12 is a side sectional view showing a modified example of the damping force adjusting mechanism.

FIG. 13 is a side sectional view showing another modified example of the damping force adjusting mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Hydraulic shock absorber, 15 ... Base housing (constituent member), 21 ... Upper oil chamber, 22 ... Lower oil chamber, 55 ... Oil passage (throttle part), 56V ... Needle (throttle member), 80 ... Damping force adjusting mechanism , 87 ... Cap (stator), 88 ... Adjuster (rotator), 89 ... Knob (operator), 106 ... Stopper part, 110 ... Pin insertion hole, 112 ... Coil spring (biasing member), 113 ... Ball (Protruder), L ... hydraulic oil.

Claims (3)

[Claims] 1. A damping force is obtained by changing the flow resistance of the hydraulic oil passing through the throttle by advancing and retracting the throttle member with respect to the throttle that connects the plurality of oil chambers provided in the shock absorber to each other. A damping force adjusting mechanism of a hydraulic shock absorber for adjusting a stator, the stator being fixed to a constituent member of the shock absorber, an operator rotatably attached to the stator, and a stator facing the stator. A rotor that is disposed and rotates integrally with the operating element, and the rotation causes the diaphragm member to advance and retreat with respect to the diaphragm portion, and one of the facing surfaces of the stator and the rotor. On one side, a plurality of pin insertion holes are formed concentrically at equal intervals around the rotation axis of the rotator, and at least one of them is inserted with a pin, and on the other side , The pin comes into contact with the rotation of the rotator, and the diaphragm member moves. Hydraulic shock absorber damping force adjusting mechanism, wherein a stopper portion for regulating is formed. 2. The stator, the operator and the rotator are disassembledly assembled, and in the assembled state, the pin inserted into the pin insertion hole is inserted into the pin insertion hole by the operator. The damping force adjusting mechanism for a hydraulic shock absorber according to claim 1, wherein the state is maintained. 3. A protrusion, which is urged toward the pin insertion hole by an urging member, is fitted into the pin insertion hole with the rotation of the rotator. The damping force adjusting mechanism for a hydraulic shock absorber according to claim 1, wherein the damping force adjusting mechanism is provided so as to be able to escape.