JP2015197104A - suspension device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suspension device etc. which achieves better durability.SOLUTION: A suspension device includes: an inner tube 110; an outer tube 210; an axle holder 120; an outer cylinder 150 and an inner cylinder 160 which are disposed at the inner side of the inner tube 110; a coil spring 300 disposed in a space between the inner tube 110 and the outer cylinder 150; a formation member 140 which is attached to an upper end part of the outer cylinder 150 and forms a working fluid chamber filled with a working fluid in an internal space of the outer cylinder 150; a piston rod 230 in which a part thereof penetrates through the formation member 140; a piston 220 attached to a lower end part of the piston rod 230; and a damping force generating part 400 which generates a damping force when the inner tube 110 and the outer tube 210 relatively move as the piston 220 moves.

Description

  The present invention relates to a suspension device disposed between a vehicle body such as a motorcycle and wheels.

Conventionally, as a front fork (suspension device) applied to a vehicle such as a two-wheeled vehicle, a flow path is formed in a piston moving in the axial direction of a cylinder, and a damping force is generated by circulating oil (hydraulic oil) through the flow path. An obtaining device has been proposed.
For example, Patent Document 1 discloses a front fork having an internal first chamber that is at least partially filled with a first fluid that is oil, and the external structure of the front fork is each when an external force is applied. Created by a relatively moving outer member and inner member, the movement is controlled by the main spring and attenuated by the damping part, which is sealed from the first space inside the front fork and higher than the ambient pressure A damping cylinder filled with a second fluid pressurized with pressure, the damping cylinder having a second chamber and divided into two damping chambers by a piston fixed by a piston rod, the piston rod being damped Extending to a first seal head fixed to one end of the cylinder, the outside of the damping cylinder is connected to the first seal head. A third chamber filled with a gas, preferably air, is arranged adjacent to the main body and is preferably a third chamber filled with gas and a first fork filled with oil inside. The boundary between the chamber and the boundary between the third chamber filled with gas and the second chamber of the damping cylinder filled with oil each include at least one seal for sealing between the fluid and the gas, Are preferably X-rings or lip seals.
Further, in Patent Document 2, a pressure side flow path for flowing the oil in the piston side oil chamber from the outer flow path of the cylinder toward the rod side oil chamber in the pressure side stroke is provided in the damping force generator, and upstream of the pressure side flow path. A pressure-side damping valve is provided on the side, and a pressure-side check valve is provided on the downstream side. The extension side flow path that flows from the piston side oil chamber to the piston side oil chamber is provided in the damping force generator, the extension side damping valve is provided upstream of the extension side flow path, and the extension side check valve is provided downstream. There is described a hydraulic shock absorber in which an intermediate portion between an extension side damping valve and an extension side check valve in a passage is communicated with an oil reservoir chamber.

International Publication No. 2008/085097 Pamphlet JP 2011-27255 A

When manufacturing suspension systems, especially when used in mass-produced vehicles, it is important that the structure be simpler and that it is possible to manufacture at a lower cost by improving the productivity by not requiring the accuracy of assembly of each part. . It is also necessary to make it more durable.
An object of the present invention is to provide a suspension device and the like that are excellent in productivity, can be manufactured at a lower cost, and are more durable.

  For this purpose, the suspension device of the present invention is a suspension device for connecting a vehicle body and a wheel, and includes a cylindrical inner tube and a cylindrical member arranged on the radially outer side of the inner tube. An outer tube that moves relative to the inner tube in the axial direction of the inner tube, an axle holder that covers an opening on the axle side of the inner tube, and an axle holder side that is disposed radially inward of the inner tube. A cylindrical outer cylinder that is mounted on the axle holder side so as to be disposed radially inside the outer cylinder, and that forms an outer oil chamber in a space between the outer cylinder and An elastic member that is disposed on the axle holder side in the space between the inner tube and the outer cylinder and absorbs an impact when the inner tube and the outer tube move relative to each other; A forming member that is attached to the upper end portion of the outer cylinder and forms a working oil chamber in which the inner space of the outer cylinder is filled with working oil, and partly penetrates the forming member and enters the working oil chamber, together with the outer tube A penetrating member that moves relative to the inner tube, an oil chamber in the inner cylinder that is attached to an end of the penetrating member on the axle side, and an upper oil chamber located above and a lower oil chamber located below And a damping force generator that generates a damping force by circulating hydraulic oil between the lower oil chamber and the outer oil chamber as the partition member moves.

  ADVANTAGE OF THE INVENTION According to this invention, the suspension apparatus etc. which were excellent in durability can be provided.

1 is a diagram showing a schematic configuration of a motorcycle according to the present embodiment. It is sectional drawing of the front fork which concerns on embodiment of this invention. FIG. 3 is an enlarged view of a part III in FIG. 2. It is an enlarged view of the IV section of FIG. It is an enlarged view of the V section of FIG. It is an enlarged view of the VI section of FIG. (A) And (b) is a figure for demonstrating operation | movement of a damping force generation part. (A) And (b) is a figure for demonstrating operation | movement of a damping force generation part.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing a schematic configuration of a motorcycle 1 according to the present embodiment.
The motorcycle 1 includes a vehicle body 10 having a front wheel 2 that is a front wheel, a rear wheel 3 that is a rear front wheel, a body frame 11 that forms a skeleton of the motorcycle 1, a handle 12, an engine (not shown), and the like. And. The motorcycle 1 also has a front fork 21 that connects the front wheel 2 and the vehicle body 10, one on each of the left and right sides of the front wheel 2, and a rear suspension 22 that connects the rear wheel 3 and the vehicle body 10. Is provided between the rear wheel 3 and the vehicle body 10. FIG. 1 shows only the front fork 21 arranged on the left side. The motorcycle 1 is disposed between the two brackets 14 and the two brackets 14 holding the front fork 21 disposed on the left side of the front wheel 2 and the front fork 21 disposed on the right side of the front wheel 2. A stem shaft (not shown). The stem shaft is rotatably supported by the head pipe 15 of the vehicle body frame 11.

Next, the front fork 21 will be described in detail.
FIG. 2 is a cross-sectional view of the front fork 21 according to the embodiment of the present invention.
FIG. 3 is an enlarged view of a portion III in FIG.
FIG. 4 is an enlarged view of a portion IV in FIG.
FIG. 5 is an enlarged view of a portion V in FIG.
FIG. 6 is an enlarged view of a VI part in FIG.
The front fork 21 according to the present embodiment is disposed between the vehicle main body 10 and the front wheel 2 of the motorcycle 1 to support the front wheel 2, and an inner tube 110 described later is disposed on the front wheel 2 side and an outer tube 210 is disposed on the vehicle main body. This is a so-called inverted front fork disposed on the 10 side.

The front fork 21 includes an axle side unit 100 that has an inner tube 110 and is attached to the axle of the front wheel 2, and a main body side unit 200 that has an outer tube 210 and is attached to the vehicle body 10. Further, the front fork 21 is disposed between the axle side unit 100 and the main body side unit 200, and a coil spring 300 that absorbs the impact received by the front wheels 2 due to the unevenness of the road surface, and a damping force generator that attenuates the impact. 400. Further, the front fork 21 has a spring collar 310 disposed between the coil spring 300 and the main body side unit 200.
The inner tube 110 and the outer tube 210 are substantially cylindrical members arranged coaxially, and the direction of the center line of the cylinder is hereinafter referred to as “axial direction”. In the axial direction, the vehicle body 10 side may be referred to as the upper side, and the front wheel 2 side may be referred to as the lower side.
The front fork 21 suppresses vibration by absorbing the impact received by the front wheel 2 due to the unevenness of the road surface while supporting the front wheel 2 while the axle side unit 100 and the main body side unit 200 move relative to each other in the axial direction. To do.

[Configuration of Axle Side Unit 100]
The axle unit 100 is attached to a substantially cylindrical inner tube 110 having both ends opened, and a lower end (lower end, axle end, one end) of the inner tube 110 and attached to the front wheel 2. An axle holder 120 to be attached and an O-ring 139 that seals between the inner tube 110 and the axle holder 120 are provided. Further, the axle unit 100 is disposed on the further inner side in the radial direction of the outer cylinder 150 and the substantially cylindrical outer cylinder 150 mounted on the axle holder 120 side so as to be disposed on the inner side in the radial direction of the inner tube 110. In this way, a substantially cylindrical inner cylinder 160 mounted on the axle holder 120 side and an upper end (upper end, end on the vehicle body 10 side, the other end) of the inner cylinder 160 are attached to the outer side. Arranged between the forming member 140 that forms the hydraulic oil chamber 41 in which the internal space of the cylinder 150 is filled with hydraulic oil, the axle holder 120, the outer cylinder 150 and the inner cylinder 160, and the outer cylinder 150 and the inner cylinder 160. Is attached to the axle holder 120 side.

(Configuration of inner tube 110)
The inner tube 110 has an outer diameter that is smaller than the inner diameter of the outer tube 210. When the inner tube 110 has entered the outer tube 210, the inner tube 110 and the outer tube 210 have an inner periphery. An annular gap is formed between the surfaces.

The inner peripheral surface of the inner tube 110 is basically formed with a uniform inner diameter along the axial direction, but a later-described female screw 121a of the axle holder 120 is fastened to the outer peripheral surface of the lower end portion. A male screw 111 is formed. On the other hand, the inner peripheral surface of the inner tube 110 is basically formed with a uniform outer diameter along the axial direction.
In addition, a communication hole 112 that communicates the inside and the outside is formed in the central portion of the inner tube 110 in the axial direction.

(Configuration of axle holder 120)
As shown in FIG. 2, the axle holder 120 has an insertion portion 121 to be inserted into the inner tube 110 at the upper portion, and an axle mounting portion in which an axle attachment hole 122 a that can be attached to the axle of the front wheel 2 is formed at the lower portion. Part 122. Further, the axle holder 120 has a flow part 123 that is provided outside the outer periphery of the insertion part 121 and through which oil for generating damping force flows outside the inner tube 110.

  The inner peripheral surface of the insertion portion 121 is formed along the outer peripheral surface of the inner tube 110, and a female screw 121a to which the male screw 111 formed on the inner tube 110 is tightened is formed at the lower portion of the inner peripheral surface. A ring groove 121b into which the O-ring 139 is fitted is formed in the upper part of the outer peripheral surface. With the O-ring 139 fitted in the ring groove 121b, the axle holder 120 holds the inner tube 110 in a state of being fluid-tightly screwed so that oil does not leak.

  The axle holder 120 has a first recess 124a that is a substantially cylindrical recess whose axial direction is the center line direction from the upper end of the insertion portion 121, and an axial direction that is the center line direction from the lower end of the first recess 124a. A second recess 124b that is a substantially cylindrical recess, a third recess 124c that is a substantially cylindrical recess whose axial direction is the center line direction from the lower end of the second recess 124b, and an axial direction from the lower end of the third recess 124c. A fourth recess 124d, which is a substantially cylindrical recess, is formed in the center line direction. The inner diameter of the second recess 124b is smaller than the inner diameter of the first recess 124a, and the inner diameter of the third recess 124c is smaller than the inner diameter of the second recess 124b. Further, the inner diameter of the fourth recess 124d is smaller than the inner diameter of the third recess 124c.

  The circulation portion 123 includes a first cross-direction concave portion 127 that is a substantially cylindrical concave portion in which the cross direction that is a direction intersecting the axial direction is the center line direction, and the axle mounting portion 122 side ( Hereinafter, it may be referred to as a “proximal end side.”) A second cross-direction concave portion 128 that is a substantially conical concave portion whose crossing direction is a center line direction from the end portion, and a base end in the second cross-direction concave portion 128. A third cross-direction recess 129 is formed that is a substantially cylindrical recess whose cross direction is the centerline direction from the end on the side. And the distribution | circulation part 123 is the front-end | tip surface orthogonal to a cross direction at the edge part of the 1st cross direction recessed part 127 on the opposite side (henceforth a "tip side" may be hereafter called) the axle attachment part 122 side. 123a. A female thread 123b is formed on the side of the first cross direction recess 127.

  In addition, the circulation portion 123 has a protruding portion 130 that protrudes upward in a cylindrical shape above the distal end surface 123a. A female screw 131 to which a male screw 451 a formed in a space forming member 451 of the pressurizing unit 450 described later is fastened is formed on the inner peripheral surface of the protruding portion 130. The space forming member 451 of the pressurizing unit 450 is liquid-tightly held in the axle holder 120 by tightening the male screw 451 a to the female screw 131.

  The axle holder 120 includes a base end side communication hole 132 that connects the base end side end of the third cross direction recess 129 of the flow portion 123 and the fourth recess 124 d, and a first cross direction of the flow portion 123. A front end side communication hole 133 that connects the concave portion 127 and the second cross direction concave portion 128 and the second concave portion 124b is formed. Further, the axle holder 120 is formed with a central communication hole 134 that communicates the central portion in the cross direction of the third cross direction recess 129 of the flow portion 123 with the inside of the protrusion 130.

(Configuration of outer cylinder 150)
The outer cylinder 150 is a thin cylindrical member. A male screw 151 to be fastened to a female screw 171c formed on the bottom holder 170 is formed at the lower end portion, and a forming member 140 is formed at the upper end portion. A female screw 152 to be fastened to a male screw 145c described later is formed.
In the outer cylinder 150, a male screw 151 formed at the lower end is fastened to a female screw 171 c formed in the bottom holder 170. Further, the outer cylinder 150 is liquid-tightly held by the bottom holder 170 when an O-ring 175 (described later) fitted into the bottom holder 170 is pressed against the outer cylinder 150.

(Configuration of the inner cylinder 160)
The inner cylinder 160 is a thin cylindrical member, and a lower end is fitted into the bottom holder 170, and a female screw 162 that is tightened to a male screw 143a (described later) formed on the forming member 140 is formed at the upper end. ing. A communication hole 163 as an example of a communication mechanism that communicates the inside and outside of the inner cylinder 160 is formed below the female screw 162. Although described in detail later, the hydraulic oil can be circulated between the annular oil chamber 53 and the upper oil chamber 52 through the communication hole 163.
The inner cylinder 160 is liquid-tightly held by the bottom holder 170 when an O-ring 176 described later fitted into the bottom holder 170 at the lower end is pressed against the inner cylinder 160.

(Configuration of forming member 140)
As shown in FIG. 3, the forming member 140 is attached to the upper end portion of the outer cylinder 150 and covers the upper openings of the outer cylinder 150 and the inner cylinder 160. The forming member 140 includes a rod guide main body 141 that supports a piston rod 230, which will be described later, so as to be slidable in the axial direction, and a rod guide case 145 disposed on the upper side with respect to the rod guide main body 141.

The rod guide body 141 includes a substantially cylindrical first cylindrical portion 142, a substantially cylindrical second cylindrical portion 143 projecting downward from a lower end portion of the first cylindrical portion 142, and an outer periphery of the piston rod 230. An O-ring 144 that seals between the surfaces is provided.
A ring groove 142a that is recessed from the upper end surface is formed at the upper end of the first cylindrical portion 142, and an O-ring 144 is fitted into the ring groove 142a.
Further, the lower end portion of the first cylindrical portion 142 has an abutting surface 142b that is formed so as to be substantially orthogonal to the axial direction and against which the upper end surface of the inner cylinder 160 abuts.

A male screw 143 a to which a female screw 162 formed at the upper end portion of the inner cylinder 160 is fastened is formed on the inner peripheral surface of the lower end portion of the second cylindrical portion 143.
Further, the lower end portion of the second cylindrical portion 143 is formed so as to be substantially orthogonal to the axial direction, and an upper end portion of a rebound spring 235, which will be described later, abuts to suppress the upward movement of the rebound spring 235. A contact surface 143b is provided.

The rod guide case 145 is a substantially cylindrical member, and has an O-ring 146 that seals between the inner peripheral surface of the outer cylinder 150 and a packing 147 that seals between the outer peripheral surface of the piston rod 230. doing.
A ring groove 145a that is recessed from the outer peripheral surface is formed in the outer peripheral portion of the rod guide case 145, and an O-ring 146 is fitted into the ring groove 145a. A groove 145b that is recessed from the lower end surface is formed at the lower end of the rod guide case 145, and a packing 147 is fitted into the groove 145b.

  A male screw 145c to which a female screw 152 formed at the upper end of the outer cylinder 150 is fastened is formed below the ring groove 145a on the outer periphery of the rod guide case 145.

The forming member 140 configured as described above is held in the outer cylinder 150 by the male screw 145c formed in the rod guide case 145 being fastened to the female screw 152 of the outer cylinder 150. The O-ring 146 fitted in the ring groove 145a of the rod guide case 145 is compressed from the inner surface of the ring groove 145a or the outer cylinder 150, so that the oil filled in the outer cylinder 150 is supplied to the O-ring. Accumulate below 146.
That is, the forming member 140 has a space in the inner tube 110 below the O-ring 146 and a hydraulic oil chamber 41 in which a part of the oil filled in the outer cylinder 150 circulates as hydraulic oil, and the O-ring. It is a space above 146 and is partitioned into an air chamber 42 filled with oil or air that circulates as lubricating oil. Lubricating oil passes through a communication hole 112 formed in the inner tube 110, an annular gap formed between the inner surface of the inner tube 110, the outer peripheral surface of the inner tube 110, and the inner peripheral surface of the outer tube 210, Between the inner tube 110 and the outer tube 210 and the sliding portion of the coil spring 300 are lubricated.

  A space sandwiched between the inner peripheral surface of the outer cylinder 150 and the outer peripheral surface of the inner cylinder 160 may be referred to as an annular oil chamber 53. The annular oil chamber 53 functions as an example of an outer oil chamber that is a space formed between the outer cylinder 150 and the inner cylinder 160.

(Configuration of bottom holder 170)
The bottom holder 170 includes a substantially cylindrical first cylindrical portion 171, a substantially cylindrical second cylindrical portion 172 protruding downward from a lower end portion of the first cylindrical portion 171, and an inner periphery of the axle holder 120. O-rings 173 and 174 that seal between the surfaces, an O-ring 175 that seals between the outer peripheral surfaces of the outer cylinder 150, and an O-ring 176 that seals between the outer peripheral surfaces of the inner cylinder 160 ing.

A ring groove 171a that is recessed from the outer peripheral surface is formed on the outer peripheral portion of the first cylindrical portion 171, and an O-ring 173 is fitted into the ring groove 171a.
A ring groove 171b that is recessed from the inner sliding surface is formed in the inner peripheral portion of the first cylindrical portion 171, and an O-ring 175 is fitted into the ring groove 171b.

  A ring groove 172a that is recessed from the lower end surface is formed on the lower end surface of the second cylindrical portion 172, and an O-ring 174 is fitted into the ring groove 172a. A ring groove 172b that is recessed from the inner peripheral surface is formed in the inner peripheral portion of the second cylindrical portion 172, and an O-ring 176 is fitted into the ring groove 172b.

  The second cylindrical portion 172 has a plurality of (for example, four) communication holes 172c formed in a direction substantially orthogonal to the axial direction. The communication hole 172 c is connected to the front end side communication hole 133 and the annular oil chamber 53.

  Further, a washer 301 is disposed on the upper end surface of the first cylindrical portion 171, and the coil spring 300 abuts on the washer 301, thereby suppressing downward movement of the coil spring 300.

With the above configuration, the bottom holder 170 is fitted with the outer cylinder 150 and the inner cylinder 160, and the space between the inner tube 110 and the outer cylinder 150 at the place where the bottom holder 170 is arranged, the outer cylinder 150 and The space between the inner cylinder 160 and the inner space of the inner cylinder 160 are partitioned in a liquid-tight manner.
Further, the communication hole 172 c mediates the flow of hydraulic oil between the front end side communication hole 133 and the annular oil chamber 53. As a result, the damping force generator 400 and the annular oil chamber 53 are connected.

[Configuration of main unit 200]
As shown in FIG. 2, the main unit 200 includes a substantially cylindrical outer tube 210 having both ends opened, a guide bush 211 attached to a lower end (lower end) of the outer tube 210, and a guide bush. And an oil seal 212 attached below 211.
The main unit 200 includes a piston 220 as an example of a partition member that slides inside the inner cylinder 160, a piston rod 230 as an example of a penetrating member that holds the piston 220 at the lower end, and a piston. And a cap 240 that holds the rod 230 and covers the upper open end of the outer tube 210. Further, as shown in FIG. 3, the main unit 200 includes a rebound spring 235 that absorbs an impact when the piston 220 moves in the maximum extension direction, and a bump rubber 239 held by the piston rod 230. ing.
(Configuration of outer tube 210)
The outer tube 210 is a member that is disposed radially outside the inner tube 110 and moves relative to the inner tube 110 in the axial direction of the inner tube 110. As shown in FIG. 2, the outer tube 210 is a substantially cylindrical member, but the lower part is enlarged so that the guide bush 211 and the oil seal 212 can be held inside, and the inner peripheral surface of the upper part. The female screw 210a to which the male screw 252a formed on the cap 240 is fastened is formed. Further, a concave portion 210b that is recessed over the entire circumference is formed slightly above the central portion of the outer tube 210 in the axial direction. A guide bush 213 for smooth sliding with the outer peripheral surface of the inner tube 110 is fitted in the recess 210b.

  The guide bushes 211 and 213 are members for smooth sliding between the inner peripheral surface of the outer tube 210 and the outer peripheral surface of the inner tube 110. These guide bushes 211 and 213 are cylindrical bearings, and in a state where they are attached to the outer tube 210, the guide bushes 211 and 213 are guides so that the inner peripheral surface protrudes inward from the inner peripheral surface of the outer tube 210. The inner diameters of the bushes 211 and 213 are set smaller than the inner diameter of the outer tube 210.

(Configuration of piston 220)
The piston 220 is a member attached to the lower end portion (end portion on the axle side) of the piston rod 230. The piston 220 is a substantially cylindrical member having a through hole, and the piston rod 230 is passed through the through hole.
The outer diameter of the piston 220 is formed to be smaller than the inner diameter of the inner cylinder 160. A groove 221a that is recessed from the outer peripheral surface is formed in the outer peripheral portion of the piston 220, and a piston ring 224 is fitted into the groove 221a.
A nut 225 is disposed on the lower side of the piston 220, and the nut 225 is fastened to a male screw 231 formed at a lower end portion of a piston rod 230 described later.
In addition, a rebound spring 235 is disposed on the upper side of the piston 220, and the lower end portion of the rebound spring 235 abuts against the upper end surface of the piston 220, thereby suppressing the downward movement of the rebound spring 235.

  The piston 220 configured as described above is held by the piston rod 230 when the male screw 231 formed at the lower end of the piston rod 230 is fastened to the nut 225. The piston ring 224 fitted into the piston 220 is compressed from the groove 221a or the inner peripheral surface of the inner cylinder 160, so that the space in the inner cylinder 160 is lowered below the piston ring 224. And an upper oil chamber 52 located above the piston ring 224.

(Configuration of piston rod 230)
The piston rod 230 is a member that partially penetrates the forming member 140 and enters below the forming member 140 and moves relative to the inner tube 110 together with the outer tube 210. The piston rod 230 is a cylindrical member, and a male screw 231 fastened to the nut 225 is formed at the lower end portion, and a female screw 272b (described later) formed on the adjustment member 270 of the cap 240 is formed at the upper end portion. A male screw 232 to be tightened is formed.
The piston rod 230 is held by the cap 240 by tightening the male screw 232 formed on the upper end portion with the female screw 272 b formed on the adjustment member 270 of the cap 240.

  The piston rod 230 is formed with a male screw 231 at the lower end, and the piston 220 is held by the piston rod 230 by tightening a nut 225 to the male screw 231.

(Configuration of cap 240)
As shown in FIG. 4, the cap 240 has a cap base 250 serving as a base, and an adjustment member 270 that is inserted inside the cap base 250 to hold the piston rod 230 and adjust the length of the coil spring 300. doing. The cap 240 includes a slider 280 that slides in the axial direction, a lock nut 285 that is fastened to the adjustment member 270, and a thrust washer 286 that is disposed between the lock nut 285 and the cap base 250. .

The cap base 250 includes a substantially cylindrical first cylindrical portion 251, a substantially cylindrical second cylindrical portion 252 protruding downward from a lower end portion of the first cylindrical portion 251, and a second cylindrical portion 252. A substantially cylindrical third cylindrical portion 253 projecting further downward from the lower end portion of the first cylindrical portion 251, and a substantially cylindrical fourth cylindrical portion 254 projecting upward from the upper end portion of the first cylindrical portion 251. Have.
A ring groove 251a that is recessed from the outer peripheral surface is formed on the outer peripheral portion of the first cylindrical portion 251, and an O-ring 251b is fitted into the ring groove 251a. In addition, the first cylindrical portion 251 has a flange portion 251 c formed at the upper end portion so that the outer diameter is larger than the inner diameter of the outer tube 210.
A male screw 252 a that is fastened to a female screw 210 a formed at the upper end of the outer tube 210 is formed on the outer peripheral surface of the second cylindrical portion 252. And the cap base 250 is airtightly hold | maintained at the outer tube 210, when the external thread 252a is fastened by the internal thread 210a.
The outer peripheral surface of the third cylindrical portion 253 is slightly smaller in diameter than the outer peripheral surface of the second cylindrical portion 252, and a gap between the third cylindrical portion 253 and the outer tube 210 is generated thereby. A holding member 260 is fitted.
A ring groove 254a that is recessed from the inner peripheral surface is formed in the inner peripheral portion of the fourth cylindrical portion 254, and an O-ring 254b is fitted into the ring groove 254a.

  The holding member 260 includes a cylindrical portion 261 that is a portion that is fitted into a gap between the third cylindrical portion 253 and the outer tube 210, and an annular ring shape that extends from the cylindrical portion 261 in a direction orthogonal to the axial direction. Part 262. The inner peripheral surface of the annular portion 262 is in contact with the outer peripheral surface of the spring collar 310, and holds the spring collar 310 on the cap 240 together with a protrusion 281 of the slider 280 described later.

The adjustment member 270 includes a substantially cylindrical first cylindrical portion 271 and a substantially cylindrical second cylindrical portion 272 that protrudes downward from the lower end portion of the first cylindrical portion 271.
The outer diameter of the first cylindrical portion 271 is formed to be equal to or smaller than the inner diameter 251 d of the first cylindrical portion 251 of the cap base 250. In addition, a ring groove 271a that is recessed from the outer peripheral surface is formed on the outer peripheral portion of the first cylindrical portion 271, and an O-ring 271b is fitted into the ring groove 271a. As described above, the O-ring 271b and the above-described O-ring 254b are fitted between the cap base 250 and the adjustment member 270, so that airtightness is maintained. In addition, the first cylindrical portion 271 has a flange portion 271 e formed at the upper end portion so that the outer diameter is larger than the inner diameter of the first cylindrical portion 251 of the cap base 250.
A male screw 272a is formed on the outer peripheral surface of the second cylindrical portion 272, and a lock nut 285 is screwed with a reverse screw. A female screw 272b to which a male screw 232 formed at the upper end of the piston rod 230 is fastened is formed on the inner peripheral surface of the second cylindrical portion 272.

The slider 280 is a substantially cylindrical member, and a hexagonal fitting hole 280a that fits with a hexagon that is the outer shape of the lock nut 285 is formed in the inner peripheral portion. A protrusion 281 is formed on the outer peripheral surface of the slider 280. In the slider 280, the spring collar 310 is fitted into the lower end portion, and the upper end portion of the spring collar 310 abuts at the lower end portion of the projecting portion 281, thereby restricting the upward movement of the spring collar 310.
The outer shape of the upper end surface of the lock nut 285 is formed larger than the outer shape of the lower end surface of the first cylindrical portion 271 of the adjustment member 270, and the upper end surface of the lock nut 285 hits the lower end surface of the thrust washer 286. The adjustment member 270 is prevented from coming off from the cap base 250.

  The cap 240 configured as described above is airtightly screwed into the outer tube 210 by tightening the male screw 252a formed on the cap base 250 to the female screw 210a formed on the upper end portion of the outer tube 210. A lock nut 285 is fastened to the male screw 272a of the adjustment member 270 inserted from the second cylindrical portion 272 side into the cap base 250. The lock nut 285 is also fitted in the fitting hole 280a of the slider 280. When the adjustment member 270 is rotated, the slider 280 rotates and moves in the axial direction as the lock nut 285 fixed to the adjustment member 270 rotates. As the slider 280 moves in the axial direction, the spring collar 310 that supports the upper end surface of the coil spring 300 moves in the axial direction. With such a configuration, the spring length of the coil spring 300 can be adjusted by rotating the adjustment member 270, and the initial set load of the coil spring 300 can be adjusted.

[Configuration of Coil Spring 300]
The coil spring 300 is an example of an elastic member that absorbs an impact when the inner tube 110 and the outer tube 210 move relative to each other.
The coil spring 300 is disposed on the axle holder 120 side in the space between the inner tube 110 and the outer cylinder 150. Further, the coil spring 300 is disposed below the forming member 140.
The lower end portion of the spring collar 310 abuts on the upper end portion of the coil spring 300 and restricts the upward movement of the coil spring 300. Since the upper end portion of the spring collar 310 abuts against the cap 240 as described above, when the inner tube 110 and the outer tube 210 move relative to each other, the movement on the outer tube 210 side causes the coil spring 300 to move through the spring collar 310. It is transmitted to. And the impact at the time of movement is absorbed by the elastic force of the coil spring 300. Therefore, the spring collar 310 is mounted on the outer tube 210 side and functions as a propagation member that transmits the relative movement of the inner tube 110 and the outer tube 210 to the coil spring 300.

[Configuration of Damping Force Generation Unit 400]
The damping force generator 400 generates a damping force when the inner tube 110 and the outer tube 210 move relative to each other. As shown in FIG. 6, the damping force generator 400 is disposed between the first valve unit 410 and the second valve unit 420 that generate damping force, and between the first valve unit 410 and the second valve unit 420. An intermediate member 430, a base member 440 to which the first valve unit 410, the second valve unit 420, and the intermediate member 430 are attached, and a nut 445 for suppressing the first valve unit 410 and the like from dropping off from the base member 440. It is equipped with. The damping force generation unit 400 includes a pressurizing unit 450 (see FIG. 2) that pressurizes hydraulic oil used for generating the damping force, a damping force adjusting unit 460 that adjusts the damping force, and a first intersection of the axle holder 120. And a cap 470 that covers the opening of the directional recess 127.

  The base member 440 includes a first cross-direction recess 127 formed in the flow portion 123 of the axle holder 120 in a state where the first valve unit 410, the second valve unit 420, the intermediate member 430, the cap 470, and the like are mounted. The second cross direction recess 128 and the third cross direction recess 129 are inserted in the cross direction from the front end side toward the base end side and attached to the axle holder 120.

(Configuration of the first valve unit 410)
As shown in FIG. 6, the first valve unit 410 is disposed at a first flow path forming member 411 that forms a flow path of a fluid that generates a damping force, and an end portion on the distal end side of the first flow path forming member 411. The first damping valve 412 that opens and closes the flow path on the distal end side of the first flow path forming member 411 according to the flow of the fluid, and the first end provided on the proximal end side of the first flow path forming member 411 1 damping check valve 413. Further, the first valve unit 410 is between the first flow path forming member 411 and the side surface 129a of the third cross-direction recess 129 of the axle holder 120 (hereinafter sometimes referred to as “third side surface 129a”). And an O-ring 414 provided in between.

  The first flow path forming member 411 is a member formed in a thick, substantially cylindrical shape, and has an outer diameter substantially equal to the inner diameter of the third side surface 129a. The first flow path forming member 411 has a through hole 411a formed in the cross direction to pass a shaft portion 442 described later of the base member 440, and a cross direction in a portion radially outside the through hole 411a. A first pressure side flow path 411b made of a through hole formed in the first and a first extension side flow path 411c made of a through hole formed in the crossing direction are formed. Further, the first flow path forming member 411 is formed to extend in the radial direction at an end portion on the proximal end side, and communicates with the first pressure side flow path 411b, and an end portion on the distal end side. An oil passage 411e that extends in the radial direction and communicates with the first extension-side passage 411c is formed. The first pressure side channel 411b and the first extension side channel 411c are each formed in plural numbers (for example, three) at equal intervals in the circumferential direction, and communicate with the first oil chamber 61 and the intermediate oil chamber 63. Functions as a passage.

  As shown in FIG. 6, the first damping valve 412 is configured by stacking a plurality of substantially disk-shaped metal plates. In the first damping valve 412, a through hole is formed in the approximate center of each metal plate, and a shaft portion 442 described later of the base member 440 is passed through the through hole. For example, the first damping valve 412 closes the first pressure side channel 411b and opens the first extension side channel 411c.

  The first damping check valve 413 is configured by stacking a plurality of substantially disk-shaped metal plates. The first attenuation check valve 413 has a through hole formed at substantially the center of the metal plate, and a shaft portion 442 described later of the base member 440 is passed through the through hole. The first attenuation check valve 413 closes the first extension side channel 411c and opens the first pressure side channel 411b.

  The O-ring 414 seals the gap between the first flow path forming member 411 and the third side surface 129a of the axle holder 120. The O-ring 414 prevents hydraulic fluid from flowing between the outer periphery of the first flow path forming member 411 and the third side surface 129a.

(Configuration of second valve unit 420)
As shown in FIG. 6, the second valve unit 420 includes a second flow path forming member 421 that forms a flow path of a fluid that generates a damping force, and an end portion on the proximal end side of the second flow path forming member 421. The second damping valve 422 that opens and closes the flow path on the proximal end side of the second flow path forming member 421 according to the flow of the fluid, and is provided at the end on the distal end side of the second flow path forming member 421. A second damping check valve 423 and an O-ring 424 provided between the second flow path forming member 421 and the third side surface 129a are provided.

  The second flow path forming member 421 is a member formed in a thick and substantially cylindrical shape, and has an outer diameter substantially equal to the inner diameter of the third side surface 129a. The second flow path forming member 421 has a through hole 421a formed in the cross direction so as to pass a shaft portion 442 described later of the base member 440, and a cross direction in a portion radially outside the through hole 421a. A second pressure side channel 421b made of a through-hole formed in the first and second extending side channels 421c made of a through-hole formed in the crossing direction are formed. Further, the second flow path forming member 421 is formed to extend in the radial direction at an end portion on the proximal end side, and communicates with the second pressure side flow path 421b, and an end portion on the distal end side. An oil passage 421e that extends in the radial direction and communicates with the second extension-side passage 421c is formed. A plurality of (for example, three) second pressure side channels 421b and second extension side channels 421c are formed at equal intervals in the circumferential direction, and communicate with the second oil chamber 62 and the intermediate oil chamber 63. Functions as a passage.

  The second damping valve 422 is configured by stacking a plurality of substantially disk-shaped metal plates. In the second damping valve 422, a through hole is formed in the approximate center of each metal plate, and a shaft portion 442 described later of the base member 440 is passed through the through hole. The second damping valve 422 opens the second pressure side channel 421b and closes the second extension side channel 421c.

  The second damping check valve 423 is configured by a substantially disk-shaped metal plate. The second attenuation check valve 423 has a through hole formed substantially at the center of the metal plate, and a shaft portion 442 described later of the base member 440 is passed through the through hole. The second attenuation check valve 423 closes the second pressure side channel 421b and opens the second extension side channel 421c.

  The O-ring 424 seals a gap between the second flow path forming member 421 and the third side surface 129a of the axle holder 120. The O-ring 424 prevents the working oil from flowing between the outer periphery of the second flow path forming member 421 and the third side surface 129a.

(Configuration of intermediate member 430)
As shown in FIG. 6, the intermediate member 430 is a substantially cylindrical member, and has an inner diameter that is greater than or equal to an outer diameter of a shaft portion 442 described later of the base member 440, and the shaft portion 442 is passed through. In the intermediate member 430, a plurality of (for example, six) side holes 431 that are radial through holes are formed at equal intervals in the circumferential direction so as to communicate the inside and the outside.

(Configuration of base member 440)
As shown in FIG. 6, the base member 440 has a bottomed cylindrical shape, a storage portion 441 that stores an operation portion 500 described later, and a cylindrical shape that protrudes from the base end side end portion of the storage portion 441 to the base end side. The shaft portion 442.
A through hole 441 a in the crossing direction is formed at the center of the bottom of the housing portion 441 so as to communicate the inside of the housing portion 441 and the inside of the shaft portion 442. In addition, a radial through hole 441b is formed in the side portion of the housing portion 441 so as to communicate the inside and the outside of the housing portion 441. A male screw 441c to which a female screw 474a formed on a holding member 472 of a cap 470, which will be described later, is fastened is formed on the outer peripheral surface of the housing portion 441. And the operation part 500 mentioned later is accommodated in the inside of the accommodating part 441. FIG.
A male screw 443 to which the nut 445 is tightened is formed at the proximal end of the shaft portion 442. Further, the inner diameter of the shaft portion 442 changes in stages, and the inner diameter of the proximal inner peripheral portion 442a that is the inner periphery of the proximal end portion is the inner periphery of the distal end portion. It is smaller than the inner diameter of the side inner peripheral portion 442b. In addition, an inclined portion 442c having an inner diameter that gradually changes is provided between the proximal end inner peripheral portion 442a and the distal end inner peripheral portion 442b. Further, a plurality of (for example, six) side holes 442d that are radial through holes are formed in the shaft portion 442 at equal intervals in the circumferential direction.

  As described above, the first valve unit 410 has the O-ring 414 that seals the gap between the first flow path forming member 411 and the third side surface 129a of the axle holder 120, and the second valve unit 420 is By having the O-ring 424 that seals the gap between the second flow path forming member 421 and the third side surface 129a, the first cross-direction concave portion 127 and the second cross-direction concave portion 128 formed in the axle holder 120. And the space in the 3rd cross direction recessed part 129 is divided into three spaces. That is, the first oil chamber 61 that is a space on the base end side with respect to the portion sealed by the O-ring 414 of the first valve unit 410 and the tip side of the portion sealed by the O-ring 424 of the second valve unit 420 The second oil chamber 62 that is the space of the first valve unit 410 and the portion sealed by the O-ring 414 of the first valve unit 410 and the portion sealed by the O-ring 424 of the second valve unit 420 It is divided into an intermediate oil chamber 63 that is a space on the base end side.

The first oil chamber 61 communicates with the lower oil chamber 51 via a base end side communication hole 132 formed in the axle holder 120, and the second oil chamber 62 communicates with a distal end side communication formed in the axle holder 120. It communicates with the annular oil chamber 53 through the hole 133 and the communication hole 172c. The intermediate oil chamber 63 communicates with the inside of the protruding portion 130 of the axle holder 120 via a central communication hole 134 formed in the axle holder 120.
Further, when the first valve unit 410, the second valve unit 420, the intermediate member 430, and the like are attached to the base member 440, the side hole 442d formed in the shaft portion 442 of the base member 440 and the intermediate member 430 The phase with the formed side hole 431 is matched. Therefore, the inside of the shaft portion 442 of the base member 440 and the intermediate oil chamber 63 communicate with each other through the side hole 442d and the side hole 431.
In this manner, the damping force generation unit 400 forms an external flow passage through which hydraulic oil flows through the lower oil chamber 51 and the annular oil chamber 53 outside the inner tube 110.

(Configuration of the pressure unit 450)
As shown in FIG. 2, the pressurizing unit 450 is fastened to a female screw 131 formed on the protruding portion 130 of the flow portion 123 of the axle holder 120 and has a thin cylindrical space forming member 451 that forms a space therein. And a cap 452 that covers the upper end of the space forming member 451, and a free piston 453 that is disposed in the space forming member 451 and partitions the space in the space forming member 451. Further, as shown in FIG. 2, the pressurizing unit 450 includes a stopper ring 454 that suppresses the cap 452 from falling off the space forming member 451.

  The space forming member 451 is a thin cylindrical member, and a male screw 451a fastened to a female screw 131 formed on the protruding portion 130 of the axle holder 120 is formed at the end (lower end) on the axle holder 120 side. Yes. The space forming member 451 is formed with a ring groove 451b that is recessed from the inner peripheral surface, and a stopper ring 454 is fitted into the ring groove 451b.

  The cap 452 is a substantially cylindrical member, and a ring groove 452a that is recessed from the outer peripheral surface is formed in the central portion in the axial direction, and an O-ring 452b is fitted in the ring groove 452a. In addition, a sealing member 452c is fitted in the cap 452 so as to prevent the filled gas from leaking through the inner hole. The cap 452 is held in the space forming member 451 in an airtight manner by preventing the cap 452 from dropping out of the space forming member 451 by the stopper ring 454 as will be described later.

The free piston 453 is a substantially columnar member, and an O-ring groove 453a and a piston ring groove 453b that are recessed from the outer peripheral surface are formed on the outer peripheral portion, and the O-ring 453c is fitted into the O-ring groove 453a. A piston ring 453d is fitted in the groove 453b. Then, the O-ring 453c fitted into the free piston 453 is compressed from the O-ring groove 453a or the inner peripheral surface of the space forming member 451, so that the space in the space forming member 451 is made higher than the O-ring 453c. There are a pressure chamber 71 that is filled with gas and pressurizes the free piston 453, and an oil reservoir chamber 72 that is located below the O-ring 453c and stores hydraulic oil.
The oil reservoir 72 communicates with the intermediate oil chamber 63 through a central communication hole 134 formed in the axle holder 120. Therefore, the oil reservoir chamber 72 is pressurized by the gas filled in the pressurizing chamber 71 via the free piston 453, and the hydraulic oil in the intermediate oil chamber 63, the lower oil chamber 51, and the annular oil chamber 53 is pressurized. The

  The stopper ring 454 is a ring-shaped member whose outer diameter is larger than the diameter of the inner peripheral surface of the space forming member 451 and whose inner diameter is smaller than the diameter of the inner peripheral surface of the space forming member 451 and the outer diameter of the cap 452. After the cap 452 is inserted into the space forming member 451, the stopper ring 454 is fitted into the ring groove 451b formed in the space forming member 451, thereby preventing the cap 452 from falling out of the space forming member 451. .

(Configuration of damping force adjustment unit 460)
As shown in FIG. 6, the damping force adjusting unit 460 adjusts the flow amount of hydraulic oil flowing between the first oil chamber 61 and the intermediate oil chamber 63 through the inside of the shaft portion 442 of the base member 440. The second adjusting unit 490 that adjusts the flow rate of the working oil flowing between the second oil chamber 62 and the intermediate oil chamber 63 through the first adjusting unit 480 and the shaft portion 442 of the base member 440. And an operation unit 500 that operates the adjustment of the first adjustment unit 480 and the second adjustment unit 490.

  The first adjustment unit 480 includes a columnar columnar portion 481 and a conical conical portion 482 provided at the proximal end of the columnar portion 481. A flange portion 481a is provided at an intermediate position on the tip side in the crossing direction of the columnar portion 481.

  The second adjustment part 490 is basically a cylindrical part, the inner diameter is formed larger than the outer diameter of the columnar part 481 of the first adjustment part 480, and the first adjustment part 480 is inserted. The end portion on the base end side is pointed so that the outer diameter becomes smaller toward the base end side. The second adjustment unit 490 according to the present embodiment is provided integrally with a second adjustment nut 521 described later. However, the second adjustment unit 490 and the second adjustment nut 521 may be separate.

  As shown in FIG. 6, the operation unit 500 includes a first operation unit 510 that moves the first adjustment unit 480 in the crossing direction, and a second operation unit 520 that moves the second adjustment unit 490 in the crossing direction. ing. The first operation portion 510 and the second operation portion 520 are accommodated in a space mainly formed by the accommodation portion 441 of the base member 440 and the cap 470.

  The first operation unit 510 is fitted to a first adjustment nut 511 that applies a force in the crossing direction to the first adjustment unit 480 and a female screw 511 a formed on the first adjustment nut 511, and the first adjustment nut 511 is inserted into the first adjustment nut 511. A first adjustment bolt 512 that moves in the crossing direction.

  The second operation portion 520 is fitted to a second adjustment nut 521 that applies a force in the crossing direction to the second adjustment portion 490, and a female screw 521a formed on the second adjustment nut 521, and the second adjustment nut 521 is fitted. A second adjusting bolt 522 that moves in the crossing direction.

  The first adjustment nut 511 is a disk-like member whose outer diameter is slightly smaller than the inner diameter of the accommodating portion 441 of the base member 440, and a female screw 511a into which the first adjustment bolt 512 is fitted and a second adjustment bolt 522 to be described later. And a through hole 511b for allowing the third cylindrical portion 522c to pass therethrough. In addition, a through hole for allowing the columnar portion 481 of the first adjustment portion 480 to pass therethrough is formed at the center of the first adjustment nut 511. Then, the end surface on the distal end side of the first adjustment nut 511 is fitted into a groove formed in the columnar portion 481 of the first adjustment portion 480 to suppress the movement of the first adjustment portion 480 relative to the first adjustment nut 511. A snap ring 511c is attached.

  The first adjustment bolt 512 is a member in which a plurality of cylindrical portions having different outer diameters are arranged in the crossing direction. More specifically, the first adjustment bolt 512 includes a first columnar portion 512a provided at an upper end portion, and a first columnar portion provided at a proximal end side with respect to the first columnar portion 512a. A second columnar portion 512b having an outer diameter larger than the outer diameter of 512a, and a third column having an outer diameter smaller than the outer diameter of the second columnar portion 512b provided on the base end side of the second columnar portion 512b. It has a columnar portion 512c and a fourth columnar portion 512d that is provided closer to the base end side than the third columnar portion 512c and has an outer diameter smaller than the outer diameter of the third columnar portion 512c.

On the outer peripheral surface of the first cylindrical portion 512a, a ring groove 512e recessed inward from the outer peripheral surface is formed over the entire periphery, and an O-ring 512f is fitted into the ring groove 512e. In addition, a concave portion 512g that is recessed from the end surface toward the base end side is formed on the end surface on the distal end side of the first cylindrical portion 512a.
The outer diameter of the second cylindrical portion 512 b is larger than the inner diameter of the through hole formed in the cylindrical portion 473 of the holding member 472 of the cap 470.
On the outer peripheral surface of the third cylindrical portion 512c, a male screw 512h that fits into the female screw 511a formed on the first adjustment nut 511 is formed.

  The second adjustment nut 521 is a disk-shaped member whose outer diameter is slightly smaller than the inner diameter of the accommodating portion 441 of the base member 440, and the female screw 521 a into which the second adjustment bolt 522 is fitted and the first adjustment bolt 512. A through-hole 521b for allowing the four cylindrical portions 512d to pass therethrough is formed. In addition, a through hole for passing the columnar portion 481 of the first adjustment portion 480 is formed in the center portion of the second adjustment nut 521. A second adjustment portion 490 is integrally provided on the end surface of the second adjustment nut 521 on the proximal end side.

  The second adjustment bolt 522 is a member in which a plurality of cylindrical portions having different outer diameters are arranged in the crossing direction. More specifically, the second adjustment bolt 522 includes a first columnar portion 522a provided at the end portion on the distal end side and a first columnar shape provided on the proximal end side with respect to the first columnar portion 522a. A second cylindrical portion 522b having an outer diameter larger than the outer diameter of the portion 522a, and a second cylindrical portion 522b having a smaller outer diameter than that of the second cylindrical portion 522b. A third columnar portion 522c, and a fourth columnar portion 522d provided on the proximal end side of the third columnar portion 522c and having an outer diameter smaller than the outer diameter of the third columnar portion 522c.

On the outer peripheral surface of the first cylindrical portion 522a, a ring groove 522e recessed inward from the outer peripheral surface is formed over the entire periphery, and an O-ring 522f is fitted into the ring groove 522e. Further, a concave portion 522g that is recessed from the end surface toward the base end side is formed on the end surface on the distal end side of the first cylindrical portion 522a.
The outer diameter of the second cylindrical portion 522b is larger than the inner diameter of the through hole formed in the cylindrical portion 473 of the holding member 472 of the cap 470.
The outer diameter of the third cylindrical portion 522c is smaller than the inner diameter of the through hole 511b formed in the first adjustment nut 511.
On the outer peripheral surface of the fourth cylindrical portion 522d, a male screw 522h that fits into the female screw 521a formed on the second adjustment nut 521 is formed.

(Configuration of cap 470)
As shown in FIG. 6, the cap 470 includes a cap base 471 serving as a base and a holding member 472 that holds the base member 440.
The cap base 471 is a cylindrical member, and has a flange portion 471 a formed so that the outer diameter is larger than the opening of the first cross-direction recess 127 of the axle holder 120 at the end portion on the distal end side. Yes. That is, the flange portion 471a is in contact with the front end surface 123a of the axle holder 120. Further, the cap base 471 is formed with a ring groove 471b that is recessed from the outer peripheral surface at a position closer to the base end than the flange portion 471a, and an O-ring 471c is fitted into the ring groove 471b. The cap base 471 has a male screw 471d fastened to a female screw 123b formed on the axle holder 120 on the outer peripheral surface of the base end side of the ring groove 471b. Further, the cap base 471 is provided with a protruding portion 471e that protrudes inward from the inner peripheral surface at an end portion on the base end side.

The holding member 472 includes a columnar columnar portion 473, a cylindrical proximal end cylindrical portion 474 that protrudes from the proximal end of the columnar portion 473 toward the proximal end, and a distal end of the columnar portion 473. A cylindrical tip-side cylindrical portion 475 protruding from the end on the side to the tip side.
The columnar portion 473 has a through hole in the crossing direction through which the first columnar portion 512a of the first adjustment bolt 512 passes, and a through hole in the crossing direction through which the first columnar portion 522a of the second adjustment bolt 522 passes. A hole is formed. A ring groove 473a that is recessed from the outer peripheral surface is formed on the outer peripheral portion of the cylindrical portion 473, and an O-ring 473b is fitted into the ring groove 473a.
A female screw 474 a that is fastened to a male screw 441 c formed in the housing portion 441 of the base member 440 is formed at the proximal end of the proximal cylindrical portion 474.
The holding member 472 holds the base member 440 by tightening the male screw 441c formed on the base member 440 to the female screw 474a formed on the proximal end cylindrical portion 474. The holding member 472 also holds the cap base 471 by sandwiching the protruding portion 471e of the cap base 471 between the base end side end portion of the base end side cylindrical portion 474 and the base member 440.

  The operation unit 500 configured as described above is housed in a space mainly formed by the housing portion 441 of the base member 440 and the cap 470. At that time, the first cylindrical portion 512a of the first adjustment bolt 512 and the first cylindrical portion 522a of the second adjustment bolt 522 are inserted into the through holes formed in the cylindrical portion 473 of the holding member 472 of the cap 470, respectively. Is done.

The first adjustment nut 511 to which the first adjustment bolt 512 is screw-coupled by the rotation operation of the first adjustment bolt 512 is the third circle of the through hole 511b of the first adjustment nut 511 and the second adjustment bolt 522. Since the columnar portion 522c is fitted, rotation is prevented and the columnar portion 522c moves in the intersecting direction. Accordingly, the first adjustment unit 480 moves in the crossing direction.
On the other hand, the second adjustment nut 521 to which the second adjustment bolt 522 is screw-coupled by the rotation operation of the second adjustment bolt 522 is connected to the through hole 521b of the second adjustment nut 521 and the fourth adjustment bolt 512. Since the cylindrical portion 512d is fitted, rotation is prevented and the rod moves in the intersecting direction. Accordingly, the second adjustment unit 490 moves in the crossing direction.

In the damping force adjusting unit 460 configured as described above, the flow rate of the working oil from the first oil chamber 61 to the intermediate oil chamber 63 through the inside of the shaft portion 442 of the base member 440 is the shaft portion 442. By adjusting the position of the conical portion 482 of the first adjusting portion 480 with respect to the inclined portion 442c inside, the flow passage area is changed and adjusted.
On the other hand, the flow rate of the working oil from the second oil chamber 62 to the intermediate oil chamber 63 through the inside of the shaft portion 442 of the base member 440 is the second adjustment with respect to the inner peripheral portion 442b at the front end side inside the shaft portion 442. By adjusting the position of the portion 490, the flow path area is changed and adjusted.

<Operation of Damping Force Generation Unit 400>
FIGS. 7A, 7B, 8A, and 8B are diagrams for explaining the operation of the damping force generation unit 400. FIG. FIGS. 7A and 7B show the flow of hydraulic oil in the damping force generation unit 400 in the case of a compression stroke in which the piston 220 held at the lower end of the piston rod 230 moves downward. 8 (a) and 8 (b) are diagrams illustrating the flow of hydraulic oil in the damping force generation unit 400 in the case of the extension stroke in which the piston 220 moves upward.

(Pressure side stroke)
In the compression side stroke, the outer tube 210 moves downward relative to the inner tube 110. When the outer tube 210 moves downward, the spring collar 310 attached to the cap 240 also moves downward accordingly, so that the coil spring 300 is compressed.
At this time, the piston rod 230 attached to the cap 240 also moves downward together with the outer tube 210, so that the piston 220 moves downward. At this time, the rebound spring 235 is extended and absorbs an impact when the piston 220 moves. Further, the pressure of the hydraulic oil in the lower oil chamber 51 is increased by the movement of the piston 220. Then, the hydraulic oil in the lower oil chamber 51 flows to the first oil chamber 61 through the proximal end side communication hole 132 as indicated by an arrow C1 in FIG.
And the hydraulic fluid which flowed into the 1st oil chamber 61 flows into the 1st pressure side flow path 411b of the 1st flow path formation member 411 from the oil path 411d, as shown by arrow C2 in FIG.7 (b). Further, as indicated by an arrow C3, the hydraulic oil that has flowed into the first pressure side flow path 411b flows into the intermediate oil chamber 63 while the first damping valve 412 is bent and opened toward the distal end side. A compression-side damping force is generated by the resistance that blocks the flow of hydraulic oil by the first damping valve 412.
On the other hand, the hydraulic oil that has flowed into the first oil chamber 61 passes through the inside of the shaft portion 442 of the base member 440, the side hole 442d, and the side hole 431 as shown by an arrow C4 in FIG. It flows into the chamber 63.

The hydraulic oil that has flowed into the intermediate oil chamber 63 via the first pressure side flow path 411b and the hydraulic oil that has flowed into the intermediate oil chamber 63 via the inside of the shaft portion 442 of the base member 440 merge to form the intermediate oil chamber 63. 7 (b), the flow toward the second pressure side flow path 421b indicated by the arrow C5 and the flow toward the oil reservoir 72 via the central communication hole 134 indicated by the arrow C6 in FIG. 7 (b). Divided.
Then, the hydraulic oil that has flowed into the second pressure side flow path 421b flows into the second oil chamber 62 while the second damping check valve 423 is bent and opened toward the distal end as indicated by an arrow C7.
Then, the hydraulic oil that has flowed into the second oil chamber 62 flows into the annular oil chamber 53 through the front end side communication hole 133 as indicated by an arrow C8 in FIG.
Then, the hydraulic oil that has flowed into the annular oil chamber 53 flows into the upper oil chamber 52 through the communication hole 163 formed in the forming member 140, as indicated by an arrow C9 in FIG.

(Extension process)
In the extension stroke, the outer tube 210 moves upward relative to the inner tube 110 by the compressed coil spring 300 trying to return to its original length.
At this time, the piston rod 230 attached to the cap 240 also moves upward together with the outer tube 210, so that the piston 220 moves upward. When the piston 220 moves upward, the pressure of the hydraulic oil in the upper oil chamber 52 rises due to the movement of the piston 220. Then, the hydraulic oil in the upper oil chamber 52 flows to the annular oil chamber 53 through the communication hole 163 formed in the forming member 140 as indicated by an arrow E1 in FIG.
Then, the hydraulic oil that has flowed into the annular oil chamber 53 flows into the second oil chamber 62 through the front end side communication hole 133 as indicated by an arrow E2 in FIG.
Then, the hydraulic oil that has flowed into the second oil chamber 62 flows from the oil passage 421e to the second extension side passage 421c of the second passage formation member 421 as indicated by an arrow E3 in FIG. Further, the hydraulic oil that has flowed into the second extension side flow path 421c is moved to the intermediate oil chamber 63 while the second damping valve 422 is bent and opened toward the base end side as shown by an arrow E4 in FIG. 8B. Flowing. The extension side damping force is generated by the resistance that blocks the flow of hydraulic oil by the second damping valve 422.
On the other hand, as shown by an arrow E5 in FIG. 8B, the hydraulic oil that has flowed into the second oil chamber 62 passes through the through hole 441b formed in the housing portion 441 of the base member 440, the inside of the shaft portion 442, the side hole. It flows to the intermediate oil chamber 63 via 442d and the side hole 431.

The hydraulic oil that has flowed into the intermediate oil chamber 63 via the second extension side flow path 421c, the hydraulic oil that has flowed into the intermediate oil chamber 63 via the inside of the shaft portion 442 of the base member 440, and FIG. The hydraulic oil that has flowed from the oil reservoir 72 to the intermediate oil chamber 63 through the central communication hole 134 indicated by the arrow E6 merges, and the first oil as shown by the arrow E7 in FIG. It goes to the extension side channel 411c.
Then, the hydraulic oil that has flowed into the first extension side flow path 411c is, as indicated by an arrow E8 in FIG. 8B, the first oil chamber 61 while opening the first damping check valve 413 by bending it toward the base end side. It flows to.
Then, the hydraulic oil that has flowed into the first oil chamber 61 flows into the lower oil chamber 51 through the base end side communication hole 132 as indicated by an arrow E9 in FIG.

  Further, in the compression side stroke, as shown in FIG. 7A, the piston 220 moves downward, so that the volume of the lower oil chamber 51 is reduced and the volume of the upper oil chamber 52 is increased. On the other hand, as shown in FIG. 8A, when the piston 220 moves upward, the volume of the lower oil chamber 51 increases and the volume of the upper oil chamber 52 decreases. At these times, the hydraulic oil having a displacement volume (cross-sectional area of the piston rod 230 × displacement amount) accompanying the advance / retreat of the piston rod 230 enters and exits the oil reservoir chamber 72 through the central communication hole 134. In addition, in the oil reservoir 72, the volume of the hydraulic oil whose volume has changed due to temperature during operation is compensated.

  As described above, the damping force generator 400 causes the hydraulic oil to flow between the lower oil chamber 51 and the outer oil chamber 53 as the piston 220 moves, and the resistance generated when the hydraulic oil flows causes the inner force to flow. A damping force is generated when the tube 110 and the outer tube 210 move relative to each other.

The front fork 21 according to the present embodiment configured as described above has a triple tube configuration of the inner tube 110, the outer cylinder 150, and the inner cylinder 160 at the location of the inner tube 110. Then, by adding the forming member 140 and the bottom holder 170 to the inner tube 110, the outer cylinder 150, and the inner cylinder 160, the space inside the inner tube 110 is divided into three spaces.
Specifically, from outside to inside,
(I) Air chamber 42 between inner tube 110 and outer cylinder 150
(II) An annular oil chamber 53 between the outer cylinder 150 and the inner cylinder 160
(III) Lower oil chamber 51 and upper oil chamber 52 inside inner cylinder 160
These three spaces fall under this category.

A coil spring 300 is arranged at the lower end of the air chamber 42 in (I), and (II) and (III) are used as the hydraulic oil chamber 41.
According to this configuration, since the coil spring 300 is disposed near the lower end of the front fork 21, compared with the case where the coil spring 300 is disposed near the upper end of the front fork 21, lubricating oil is contained in the air chamber 42. As a result, the oil level of the oil circulating as can be lowered.

  Further, in the present embodiment, the lengths of the outer cylinder 150 and the inner cylinder 160 are increased, and the forming member 140 is arranged further upward. For this reason, it becomes possible to arrange | position the formation member 140 more upper than oil level height.

Thereby, it is possible to prevent oil from entering the hydraulic oil chamber 41 from the air chamber 42 through the portion of the forming member 140. For this reason, the sealing portion of the forming member 140 can have a simpler configuration, and the manufacturing cost of the front fork 21 can be further reduced.
Further, since the oil enters the hydraulic oil chamber 41, it is possible to suppress the occurrence of a puncture phenomenon because the hydraulic oil cannot be completely absorbed into the oil reservoir chamber 72 during the operation of the front fork 21. Further, the durability of the front fork 21 can be improved.

  Further, when the oil level of the oil circulating as the lubricating oil is lowered, the volume of the air chamber 42 is increased. Therefore, the influence of the air spring caused by the change in the volume of the air chamber 42 becomes smaller. As a result, the reaction force characteristic of the front fork 21 becomes better.

  Further, the forming member 140 is not attached to the inner tube 110, so that it is not necessary to perform honing on the inner surface of the inner tube 110. Moreover, according to the said structure, since the assembly precision is not required so much, the front fork 21 which is excellent in productivity and can be manufactured at a lower cost can be realized.

DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Front wheel, 10 ... Vehicle main body, 21 ... Front fork, 41 ... Hydraulic oil chamber, 42 ... Air chamber, 51 ... Lower oil chamber, 52 ... Upper oil chamber, 53 ... Annular oil chamber, 61 ... 1st oil chamber, 62 ... 2nd oil chamber, 63 ... Intermediate oil chamber, 71 ... Pressurizing chamber, 72 ... Oil reservoir chamber, 100 ... Axle side unit, 110 ... Inner tube, 120 ... Axle holder, 132 ... Base end Side communication hole, 133 ... tip side communication hole, 134 ... central communication hole, 140 ... forming member, 150 ... outer cylinder, 160 ... inner cylinder, 200 ... main body side unit, 210 ... outer tube, 220 ... piston, 230 ... Piston rod, 240 ... cap, 400 ... damping force generating part, 410 ... first valve unit, 420 ... second valve unit, 430 ... intermediate member, 440 ... base member, 450 ... pressurizing part, 460 ... reduction Force adjusting unit, 470 ... cap

Claims (4)

A suspension device for connecting the vehicle body and the wheel,
A cylindrical inner tube;
A cylindrical member disposed on the radially outer side of the inner tube, the outer tube moving relative to the inner tube in the axial direction of the inner tube;
An axle holder that covers the axle-side opening of the inner tube;
A cylindrical outer cylinder mounted on the axle holder side so as to be arranged on the inner side in the radial direction of the inner tube;
A cylindrical inner cylinder that is mounted on the axle holder side so as to be disposed radially inside the outer cylinder, and that forms an outer oil chamber in a space between the outer cylinder;
An elastic member that is disposed on the axle holder side in the space between the inner tube and the outer cylinder, and absorbs an impact when the inner tube and the outer tube move relatively;
A forming member that is attached to the upper end of the outer cylinder and forms a hydraulic oil chamber filled with hydraulic oil in the inner space of the outer cylinder;
A penetrating member that partially penetrates the forming member and enters the hydraulic oil chamber and moves relative to the inner tube together with the outer tube;
A partition member that is attached to an end of the penetrating member on the axle side and divides the oil chamber in the inner cylinder into an upper oil chamber located above and a lower oil chamber located below;
With the movement of the partition member, a damping force generating unit that generates a damping force by circulating hydraulic oil between the lower oil chamber and the outer oil chamber;
A suspension device comprising: A communication mechanism for communicating the outer oil chamber and the upper oil chamber;
The suspension device according to claim 1, wherein hydraulic oil is further circulated between the outer oil chamber and the upper oil chamber as the partition member moves.   2. The suspension device according to claim 1, further comprising: a bottom holder having a communication hole that attaches the outer cylinder and the inner cylinder on the axle holder side and connects the damping force generation unit and the outer oil chamber.   2. The suspension device according to claim 1, further comprising a propagation member that is attached to the outer tube side in the other end portion in the axial direction and transmits a relative movement between the inner tube and the outer tube to the elastic member.

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