JP2020003025A - Front fork - Google Patents

Abstract

To provide a front fork capable of preventing shortage of pressure-side attenuation force even when a piston speed is in a low speed region.SOLUTION: A front fork F includes: a cylinder 3 having a cylindrical shape, disposed in a wheel-side outer tube 1, movably inserted into a vehicle body-side inner tube 2 at its upper end, and partitioning an outer peripheral-side liquid chamber L and a reservoir chamber R formed from an inner side toward an upper side; a piston portion 20 disposed in the inner tube 2 and dividing the liquid chamber L into an elongation-side chamber L1 and a pressure-side chamber L2; a pressure-side orifice 6 communicating the pressure-side chamber L2 and the reservoir chamber R; and a choke member 7 forming a choke passage 8 in the pressure-side chamber L2 or the reservoir chamber R.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an improvement of a front fork.

  2. Description of the Related Art Conventionally, a front fork for suspending a front wheel of a saddle-ride type vehicle includes a telescopic tube member including an outer tube and an inner tube slidably inserted into the outer tube. . Further, among the front forks, there is a so-called upright type front fork in which an outer tube is provided on a wheel side and an inner tube is provided on a vehicle body side (for example, Patent Document 1).

  In such an upright front fork, a cylinder is provided inside the outer tube to partition a liquid chamber formed between the cylinder and a reservoir chamber formed from the inside of the cylinder to the upper side thereof, The liquid chamber is partitioned into a growth side chamber and a pressure side chamber by a piston provided at the lower end of the inner tube. Further, the cylinder is formed with an expansion-side orifice that connects the expansion-side chamber and the reservoir chamber, and a compression-side orifice that connects the compression-side chamber and the reservoir chamber.

  According to the above configuration, when the front fork is extended, the liquid in the extension side chamber moves to the reservoir chamber through the extension side orifice, and the extension side damping force is generated due to the resistance applied to the flow of the liquid. . Conversely, when the front fork contracts, the liquid in the pressure side chamber moves to the reservoir chamber through the pressure side orifice, and a pressure side damping force is generated due to the resistance applied to the flow of the liquid.

JP-A-9-217780

  In a conventional front fork, the compression side damping force is adjusted by changing the size of the compression side orifice formed in the cylinder. However, the characteristic (damping force characteristic) of the damping force with respect to the speed of the piston portion (piston speed) at the time of contraction is a square characteristic peculiar to the orifice as shown in FIG. For this reason, even if the compression-side orifice is reduced, it is difficult to increase the damping force when the piston speed is in a low-speed range, and the compression-side damping force in a low-speed range may be insufficient.

  Therefore, the present invention has been made in order to solve such a problem, and provides a front fork that can prevent insufficient pressure-side damping force even when the piston speed is in a low speed range. With the goal.

  The front fork for solving the above-mentioned problem is cylindrical and provided in an outer tube on the wheel side, the upper end is movably inserted into an inner tube on the vehicle body side, and a liquid chamber on the outer peripheral side, from the inside, A cylinder partitioning a reservoir chamber formed over the upper side, a piston portion provided in the inner tube to divide the liquid chamber into a growth side chamber and a pressure side chamber, an orifice communicating the pressure side chamber and the reservoir chamber, and a pressure side chamber or A choke member for forming a choke passage in the reservoir chamber.

  According to the above configuration, when the front fork contracts, the liquid passes through the orifice and the choke passage, and a pressure loss occurs due to these resistances, and a pressure-side damping force is generated. When the piston speed is in the low speed range when the front fork is contracted, the pressure loss due to the choke passage becomes dominant, and the pressure-side damping force has a proportional characteristic. For this reason, the compression-side damping force in the low-speed range can be increased, so that the compression-side damping force in the low-speed range can be prevented from becoming insufficient.

  In the front fork, the choke passage may be formed by a gap formed between the cylinder and the choke member, or a hole formed in the choke member. According to these configurations, the choke passage can be easily formed.

  In the front fork, the choke member may be arranged in the cylinder. According to this configuration, when the front fork is contracted, the choke passage is disposed downstream of the orifice, so that the liquid can easily pass through the orifice without interruption. Furthermore, since the choke member does not hinder the stroke of the front fork, the provision of the choke member can prevent the stroke length of the front fork from being secured or prevent the front fork from becoming bulky in the axial direction.

  Further, in the front fork, the opening of the choke passage on the pressure side chamber side may not be opposed to the opening of the orifice on the reservoir chamber side, and may be disposed above the opening of the orifice. According to this configuration, the liquid can easily flow back and forth between the orifice and the choke passage.

  In the front fork, the choke member may be attached to a bolt connecting the outer tube and the cylinder. According to this configuration, the choke passage can be easily formed at a predetermined position in the reservoir. Further, since the choke member can be easily attached and detached, tuning of the damping force by replacing the choke member can be facilitated.

  ADVANTAGE OF THE INVENTION According to the front fork of this invention, even when the piston speed is in a low speed area | region, it can prevent that the damping force of a compression side runs short.

It is the side view which simplified and showed the attachment state of the front fork which concerns on one Embodiment of this invention. It is a longitudinal section of a front fork concerning one embodiment of the present invention. FIG. 3 is an enlarged longitudinal sectional view showing a part of FIG. 2. It is a damping force characteristic figure of the front fork concerning one embodiment of the present invention. It is the longitudinal section which showed the 1st modification of the choke member in the front fork concerning one embodiment of the present invention, and expanded and showed the choke member part. It is the longitudinal section which showed the 2nd modification of the choke member in the front fork which concerns on one Embodiment of this invention, and expanded and showed the choke member part. FIG. 9 is a damping force characteristic diagram of a conventional front fork.

  Hereinafter, a front fork according to an embodiment of the present invention will be described with reference to the drawings. Like reference numerals throughout the several figures indicate the same or corresponding parts. The upper and lower sides of the vehicle with the front fork attached to the vehicle are simply referred to as “up” and “down” unless otherwise specified.

  As shown in FIG. 1, a front fork F according to an embodiment of the present invention is a suspension device for suspending a front wheel W in a straddle-type vehicle V. The straddle-type vehicle is a general type of vehicle that rides in a posture that straddles a saddle, and includes motorcycles, scooters, bicycles, and the like. The front fork according to the present invention may be mounted on any saddle type vehicle.

  Subsequently, a specific structure of the front fork F according to one embodiment of the present invention will be described. The front fork F includes a telescopic tube member T configured to include the outer tube 1 and the inner tube 2. Further, the front fork F is an upright type, and the inner tube 2 is slidably inserted from the upper opening of the outer tube 1.

  The outer tube 1 is integrally provided with a wheel side bracket BW, and the outer tube 1 is connected to the axle of the front wheel W via the wheel side bracket BW. On the other hand, the inner tube 2 is connected to the vehicle body B via a vehicle body side bracket BB connected to an upper end portion thereof.

  As described above, the front fork F is arranged with the outer tube 1 toward the front wheel (wheel) W and the inner tube 2 toward the vehicle body B, and is interposed between the vehicle body B and the axle of the front wheel W. . When the front wheel W vibrates up and down, for example, when the saddle-ride type vehicle V runs on an uneven road surface, the inner tube 2 moves in and out of the outer tube 1 and the front fork F expands and contracts.

  Subsequently, the upper end opening of the inner tube 2 is closed with a cap (not shown). On the other hand, the outer tube 1 has a bottomed cylindrical shape as shown in FIG. 2, and a lower opening of the outer tube 1 is closed by a bottom portion 1a. Further, the space between the overlapping portion of the outer tube 1 and the inner tube 2 is closed by an oil seal 10 and a dust seal 11. Thus, the inside of the tube member T is a closed space, and the tube member T is filled with a liquid and a gas.

  The cylinder 3 is connected to the bottom 1 a of the outer tube 1 with bolts 30. The cylinder 3 includes a tubular portion 3a, and an annular valve case portion 3b that projects radially outward from the distal end of the tubular portion 3a. The tubular portion 3a stands upright along the axial direction at the center of the outer tube 1, and the valve case portion 3b is inserted inside the inner tube 2 movably in the axial direction.

  Due to the cylinder 3, the inside of the tube member T has a cylindrical liquid chamber L formed below the valve case section 3b and on the outer peripheral side of the cylindrical section 3a, and a cylindrical section formed from the inside of the cylindrical section 3a. 3a and a reservoir chamber R formed over the upper side of the valve case portion 3b. Further, the liquid chamber L on the outer peripheral side of the cylinder 3 is partitioned into an upper extension side chamber L1 and a lower pressure side chamber L2 by a piston portion 20 provided at a lower end of the inner tube 2.

  An extension spring 21 is laminated on the upper side of the piston portion 20. The extension spring 21 is compressed between the piston portion 20 and the valve case portion 3b when the front fork F is fully extended, so as to reduce the impact at the time of maximum extension. The extension spring 21 shown in FIG. 2 is a coil spring, but may be a spring other than a coil spring. Further, a cushion rubber or the like may be provided instead of the extension spring 21, and the cushion at the time of the maximum extension of the front fork F may be reduced by the cushion rubber.

  Further, a suspension spring S is laminated on the upper side of the valve case portion 3b. The upper end of the suspension spring S is supported by a cap (not shown) that closes the upper end of the inner tube 2. For this reason, it can be said that the suspension spring S of the present embodiment is interposed between the cylinder 3 and the inner tube 2.

  When the inner tube 2 enters the outer tube 1 and the front fork F contracts, the amount of compression of the suspension spring S increases, and the elastic force of the suspension spring S against the compression increases. In this manner, the suspension spring S exerts an elastic force corresponding to the amount of compression, and urges the front fork F in the extension direction to elastically support the vehicle body B.

  Note that the arrangement of the suspension spring S is not limited to that shown in the figure, and can be changed as appropriate. For example, the suspension spring S may be interposed between the lower end of the inner tube 2 and the bottom 1a of the outer tube 1. Furthermore, the suspension spring S of the present embodiment is a coil spring, but may be a spring other than a coil spring such as an air spring.

  Subsequently, the expansion-side chamber L1 and the compression-side chamber L2 are each filled with a liquid such as hydraulic oil. On the other hand, the same liquid as the above liquid is stored in the reservoir chamber R, and a gas such as air is sealed above the liquid surface. The liquid level is higher than the valve case 3b of the cylinder 3.

  An annular valve housing groove 3c is formed on the outer periphery of the valve case portion 3b. An annular check valve 4 slidingly contacting the inner periphery of the inner tube 2 is formed inside the valve housing groove 3c in the axial direction. It is inserted movably. In addition, a portion of the wall surface of the valve housing groove 3c facing the upper end of the check valve 4 is a seat surface 3d, and the check valve 4 is separated and seated on the seat surface 3d.

  When the front fork F is contracted, the check valve 4 is separated from the seat surface 3d, and the flow of the liquid from the reservoir chamber R to the expansion chamber L1 through the inner peripheral side of the check valve 4 is allowed. Conversely, when the front fork F is extended, the check valve 4 is seated on the seat surface 3d, and the state in which the communication between the reservoir chamber R and the extension side chamber L1 is shut off is maintained.

  An expansion orifice 5 communicating the expansion chamber L1 and the inside of the cylinder 3 is formed above the cylindrical section 3a of the cylinder 3, and a compression chamber L2 and a cylinder are formed below the cylindrical section 3a. A pressure-side orifice 6 is formed to communicate with the inside of the nozzle 3. Since the inside of the cylinder 3 is a part of the reservoir chamber R, it can be said that both the expansion-side orifice 5 and the compression-side orifice 6 communicate the expansion-side chamber L1 or the compression-side chamber L2 with the reservoir chamber R.

  Then, when the front fork F extends, the liquid flows from the extension side chamber L1 to the reservoir chamber R through the extension side orifice 5, and resistance is given to the flow. Conversely, when the front fork F is contracted, the liquid flows from the pressure side chamber L2 to the reservoir chamber R through the pressure side orifice 6, and resistance is given to the flow.

  Subsequently, a choke member 7 is provided in the cylinder 3 at a position facing the opening of the pressure-side orifice 6 on the reservoir chamber R side and below the opening of the expansion-side orifice 5 on the reservoir chamber R side.

  As shown in FIG. 3, the choke member 7 includes a needle-shaped valve body 7a and a screw 7b connected to the end of the valve body 7a. The choke member 7 is disposed in the cylinder 3 such that the screw portion 7b is screwed to the tip of the bolt 30, and the tip of the valve body portion 7a faces upward. The outer diameter of the valve body portion 7a is slightly smaller than the inner diameter of the cylindrical portion 3a of the cylinder 3, and the choke passage 8 is formed by a cylindrical gap formed between the valve body portion 7a and the cylinder 3.

  As described above, in the present embodiment, the choke passage 8 is formed in the lower part of the reservoir 3 in the cylinder 3. Then, when the liquid flows from the pressure side chamber L2 to the reservoir chamber R through the pressure side orifice 6 when the front fork F is contracted, the liquid in the reservoir chamber R passes through the choke passage 8 and heads above the choke member 7, and Resistance to flow is imparted.

  Further, in the present embodiment, the portion of the cylinder 3 where the pressure-side orifice 6 is formed is an enlarged diameter portion 3e whose inner diameter is larger than the portion immediately above it, and the enlarged diameter portion 3e and the choke member 7 are provided. Is set so that there is no aperture between them. In other words, in this embodiment, the opening on the pressure side chamber L2 side located at the lower end of the choke passage 8 is above the opening on the reservoir chamber R side of the pressure side orifice 6, and the choke passage 8 and the pressure side orifice 6 are in direct communication. It is not structured.

  If a portion formed between the enlarged diameter portion 3e of the cylinder 3 and the choke member 7 and connects the choke passage 8 and the pressure side orifice 6 is a connection portion 9, in the present embodiment, the connection portion 9 And a choke passage 8 are formed in the reservoir chamber R. In such a reservoir chamber R, a portion that substantially functions as a reservoir chamber is a portion excluding the connection portion 9 and the choke passage 8 above the choke member 7.

  That is, assuming that the portion which substantially functions as the reservoir chamber is the reservoir chamber portion r, in the present embodiment, the pressure side chamber L2 and the reservoir chamber portion r are connected via the pressure side orifice 6, the connection portion 9, and the choke passage 8. It is designed to communicate. On the other hand, the extension side chamber L1 is connected to the reservoir chamber r via the extension side orifice 5.

  Next, the operation of the front fork F according to one embodiment of the present invention will be described.

  When the front fork F in which the inner tube 2 retreats from the outer tube 1 extends, the inner tube 2 retreats from a cylindrical liquid chamber L formed between the outer tube 1 and the cylinder 3, and the piston portion 20 displaces the liquid. By moving upward in the chamber L, the extension side chamber L1 is reduced and the compression side chamber L2 is enlarged.

  When the front fork F is extended, the liquid in the extension side chamber L1 to be reduced moves to the reservoir chamber r (reservoir R) through the extension side orifice 5. On the other hand, the liquid in the reservoir chamber r is supplied to the expanding pressure side chamber L2 via the choke passage 8, the connection portion 9, and the pressure side orifice 6.

  When the front fork F is extended, resistance to the flow of the liquid from the extension side chamber L1 to the reservoir chamber R is given by the extension side orifice 5. For this reason, when the front fork F is extended, the pressure in the extension side chamber L1 increases, and an extension side damping force that hinders the extension operation of the front fork F is generated.

  Conversely, when the front fork F in which the inner tube 2 enters the outer tube 1 contracts, the inner tube 2 enters the cylindrical liquid chamber L formed between the outer tube 1 and the cylinder 3 and the piston The part 20 moves downward in the liquid chamber L to reduce the pressure side chamber L2 and expand the expansion side chamber L1.

  When the front fork F is contracted, the liquid in the pressure side chamber L2 to be reduced moves to the reservoir chamber R through the pressure side orifice 6 and passes through the inside of the reservoir chamber R in the order of the connecting portion 9 and the choke passage 8. Move to the reservoir chamber r. When the front fork F is contracted, the check valve 4 is opened, and the liquid in the reservoir chamber r is supplied to the expanding side chamber L1.

  When the front fork F contracts, a resistance is given to the flow of the liquid from the pressure side chamber L2 toward the reservoir chamber R by the pressure side orifice 6, and the inside of the reservoir chamber R is connected from the connection portion 9 to the reservoir chamber portion r. The choke passage 8 provides resistance to the flow of the liquid flowing toward. Therefore, when the front fork F is contracted, the pressure in the pressure side chamber L2 increases, and a pressure-side damping force that hinders the contraction operation of the front fork F is generated.

  More specifically, the pressure-side orifice 6 and the choke passage 8 provide resistance to the passing liquid to cause a pressure loss. The pressure loss due to the pressure side orifice 6, which is an orifice, has a square characteristic that increases in proportion to the square of the flow rate. On the other hand, the pressure loss due to the choke passage 8 has a proportional characteristic that increases in proportion to the flow rate.

  When the flow rate of the passing liquid is small, the pressure loss caused by the pressure-side orifice 6 is smaller than the pressure loss caused by the choke passage 8. However, the pressure loss caused by the pressure-side orifice 6 overtakes the pressure loss caused by the choke passage 8 as the flow rate increases. It is set to be large.

  Further, since the flow rate is proportional to the speed of the piston portion 20 (piston speed), when the piston speed is in a low speed range when the front fork F is contracted, the pressure loss due to the choke passage 8 becomes dominant. For this reason, the pressure-side damping force in the low-speed region has a proportional characteristic that increases proportionally with an increase in the piston speed as shown by a solid line a in FIG. It becomes larger than the damping force on the pressure side in the low speed range.

  On the other hand, when the piston speed at the time of contraction of the front fork F is in the middle to high speed range beyond the low speed range, the pressure loss due to the pressure side orifice 6 becomes dominant. For this reason, as shown by a solid line b in FIG. 4, the pressure-side damping force in the middle to high speed region has a square characteristic that increases in proportion to the square of the piston speed as the piston speed increases. It becomes equal to the compression damping force in the high speed range.

  Next, the operation and effect of the front fork F according to one embodiment of the present invention will be described.

  The front fork F of the present embodiment has an outer tube 1 on a front wheel (wheel) W side, an inner tube 2 on a vehicle body B side slidably inserted into the outer tube 1, an outer tube 1 having a tubular shape, and A cylinder 3 is provided in the tube 1 and has an upper end movably inserted into the inner tube 2. The cylinder 3 separates a liquid chamber L on the outer peripheral side of the cylinder 3 and a reservoir chamber R formed from the inside to the upper side of the cylinder 3.

  Further, the front fork F of the present embodiment is provided in the inner tube 2 and communicates the piston portion 20 that divides the liquid chamber L into the expansion chamber L1 and the compression chamber L2, and communicates with the compression chamber L2 and the reservoir chamber R. A pressure side orifice (orifice) 6 and a choke member 7 forming a choke passage 8 in the reservoir chamber R are provided.

  According to the above configuration, when the front fork F is contracted, the liquid passes through the pressure-side orifice (orifice) 6 and the choke passage 8, and a pressure loss occurs due to these resistances, and a pressure-side damping force is generated. When the piston speed is in the low speed range when the front fork F is contracted, the pressure loss due to the choke passage 8 becomes dominant, and the damping force on the pressure side has a proportional characteristic (solid line a in FIG. 4).

  For this reason, in the front fork F of the present embodiment, as compared with a case where a compression-side orifice generates a compression-side damping force only by a compression-side orifice (broken line c in FIG. 4, FIG. 7), as in a conventional front fork, Pressure side damping force can be increased. Therefore, according to the front fork F of the present embodiment, even when the piston speed is in the low speed range, it is possible to prevent the pressure-side damping force from becoming insufficient.

  Further, the main change from the conventional front fork required to exhibit such an effect is only the addition of the choke member 7. For this reason, according to the above configuration, a structure for preventing the shortage of the compression side damping force when the piston speed is in the low speed range can be realized at very low cost.

  In the present embodiment, the region of the piston speed is divided into a low speed region and a medium / high speed region, but the threshold of each region can be set arbitrarily.

  In the front fork F of the present embodiment, the choke passage 8 is formed by a gap formed between the cylinder 3 and the choke member 7. Therefore, the choke passage 8 can be easily formed. The method of forming the choke passage 8 can be changed as appropriate. For example, a choke passage may be formed by a hole formed in the choke member 7, and in this case, the choke passage can be easily formed.

  Further, in the present embodiment, the lower end (opening on the pressure side chamber L2 side) of the choke passage 8 is a position not opposed to the opening on the reservoir chamber R side of the pressure side orifice (orifice) 6, and is disposed above the opening. Have been. Thus, in the present embodiment, the structure is such that the pressure side orifice (orifice) 6 and the choke passage 8 are not directly communicated. Therefore, the liquid easily flows between the pressure-side orifice (orifice) 6 and the choke passage 8 without interruption.

  Further, in the present embodiment, the inner diameter of the portion of the cylinder 3 where the pressure-side orifice 6 is formed is enlarged to form an enlarged diameter portion 3e. According to this configuration, a connection portion 9 that does not function as a throttle is formed between the enlarged diameter portion 3 e and the choke member 7, and the pressure-side orifice (orifice) 6 and the choke passage 8 are communicated through the connection portion 9. it can. That is, according to the above configuration, a structure in which the pressure-side orifice (orifice) 6 and the choke passage 8 are not directly communicated can be easily realized.

  The configuration for improving the flow of the liquid by interposing the connecting portion 9 between the pressure side orifice (orifice) 6 and the choke passage 8 is not limited to the above, and can be appropriately changed. For example, like a choke member 7A according to a first modification shown in FIG. 5, a reduced-diameter portion 7c having a smaller outer diameter than other portions is formed at a portion facing the pressure-side orifice (orifice) 6, and the reduced-diameter portion is formed. A connecting portion 9 may be formed between the portion 7c and the cylinder 3.

  Further, the connecting portion 9 may be omitted, and the pressure side orifice (orifice) 6 and the choke passage 8 may be directly communicated.

  Further, the choke members 7 and 7A of the present embodiment including the first modified example are attached to bolts 30 that connect the outer tube 1 and the cylinder 3. Therefore, the choke passage 8 can be easily formed at a predetermined position in the reservoir chamber R.

  Further, according to the above configuration, since the choke members 7, 7A can be easily attached and detached, the tuning of the damping force can be facilitated by replacing the choke members 7, 7A. Specifically, for example, when using the choke member 7 according to one embodiment, a plurality of types of choke members 7 having valve bodies 7a having different outer diameters or axial lengths are prepared in advance, and damping is performed. When tuning the force, it may be replaced with a different type of choke member 7.

  Further, in the present embodiment including the first modified example, the choke members 7, 7A and the bolt 30 are formed separately, and these are connected by screwing. Therefore, when tuning the damping force, only the choke members 7, 7A need to be replaced, and the cost of replacement parts can be reduced.

  However, the choke members 7, 7A and the bolt 30 may be integrally formed as one component. Furthermore, the choke members 7 and 7A do not necessarily need to be attached to the bolt 30. For example, like the choke member 7B according to the second modified example shown in FIG.

  In addition, a hole penetrating in the axial direction is formed in the choke member 7B shown in FIG. 6, and the choke passage 8 is formed by the hole. However, even when the choke member 7B is fitted to the cylinder 3 as in this example, for example, a notch is formed in the outer periphery of the choke member 7B in the axial direction, and the notch is formed by the notch. The choke passage 8 may be formed by a gap formed with the cylinder 3.

  When the choke member 7B is fitted and fixed to the inner periphery of the cylinder 3 as in a choke member 7B shown in FIG. 6, if the choke member 7B is fitted above the pressure side orifice 6, The connecting portion 9 can be formed between the pressure-side orifice 6 and the choke passage 8 without forming the enlarged diameter portion 3e (FIG. 3) or forming the reduced diameter portion 7c (FIG. 5) on the choke member 7A. For this reason, it is easy to form the connection portion 9.

  Further, the choke members 7, 7A, 7B of the present embodiment including the modified examples are arranged in the cylinder 3, and the choke passage 8 is formed in the reservoir chamber R. Therefore, when the front fork F is contracted, the choke passage 8 is arranged downstream of the pressure-side orifice 6, so that the liquid easily passes through the choke passage 8 without any delay.

  Further, according to the above configuration, the choke members 7, 7A, 7B do not hinder the stroke of the front fork F. Therefore, by providing the choke members 7, 7A, 7B, it is possible to prevent the stroke length of the front fork F from being secured or the front fork F from increasing in the axial direction.

  However, the choke passage 8 may be formed in the pressure side chamber L2. In this case, for example, a cylindrical choke member may be provided at a position on the outer periphery of the cylinder 3 facing the pressure-side orifice 6, and a choke passage may be formed by a gap formed between the choke member and the cylinder 3. Further, an annular choke member fitted to the outer periphery of the cylinder 3 and the inner periphery of the outer tube 1 may be provided above the pressure-side orifice 6, and a choke passage may be formed by a hole penetrating the choke member.

  As described above, the preferred embodiments of the present invention have been described in detail, but modifications, variations, and changes can be made without departing from the scope of the claims.

B: body, F: front fork, L: liquid chamber, L1: extension side chamber, L2: compression side chamber, R: reservoir chamber, W: front wheel (wheel), DESCRIPTION OF SYMBOLS 1 ... Outer tube, 2 ... Inner tube, 3 ... Cylinder, 6 ... Pressure side orifice (orifice), 7 ... Choke member, 8 ... Choke passage, 20 ... Piston part , 30 ... bolt

Claims (6)

An outer tube on the wheel side,
An inner tube on the vehicle body side slidably inserted into the outer tube,
A cylinder that is cylindrical and provided in the outer tube, the upper end is movably inserted into the inner tube, and a liquid chamber on the outer peripheral side, and a cylinder that partitions a reservoir chamber formed from the inside to the upper side,
A piston portion provided on the inner tube, for partitioning the liquid chamber into a stretching side chamber and a pressure side chamber,
An orifice communicating the pressure side chamber and the reservoir chamber,
A choke member that forms a choke passage in the compression-side chamber or the reservoir chamber. The front fork according to claim 1, wherein the choke passage is formed by a gap formed between the cylinder and the choke member. The front fork according to claim 1, wherein the choke passage is formed by a hole formed in the choke member. The front fork according to any one of claims 1 to 3, wherein the choke member is arranged in the cylinder. The opening of the choke passage on the pressure side chamber side is a position not opposed to the opening of the orifice on the reservoir chamber side, and is disposed above the opening of the orifice. Front fork. The front fork according to claim 4 or 5, wherein the choke member is attached to a bolt that connects the outer tube and the cylinder.

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