JP2019168095A - Front fork - Google Patents

Abstract

To provide a front fork capable of easily tuning attenuation force and reducing increase of costs.SOLUTION: A front fork F includes a tube member T having a wheel-side outer tube 1 and a car body-side inner tube 2, a rod 3 connected to the outer tube 1, a partitioning member 4 connected to the rod 3 kept into slide-contact with an inner periphery of the inner tube 2, and partitioning the inside of the tube member T into a reservoir chamber R and a liquid chamber L, passages 4a, 4b formed on the partitioning member 4 and communicating the reservoir chamber R and the liquid chamber L, and attenuation valves 41, 42 opening and closing the passages 4a, 4b and applying resistance to flow of a liquid passing through the passages 4a, 4b.SELECTED DRAWING: Figure 2

Description

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

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

  And in such an upright front fork, a cylinder is provided inside the outer tube to partition a liquid chamber formed between them and a reservoir chamber formed from the inside of the cylinder to the upper side thereof, A liquid chamber is divided into an extension side chamber and a pressure side chamber by a piston portion provided at the lower end of the inner tube. Further, the cylinder is formed with an expansion side throttle hole that communicates the expansion side chamber and the reservoir chamber, and a pressure side throttle hole that communicates the compression side chamber and the reservoir chamber.

  According to the above configuration, when the front fork is extended, the liquid in the expansion side moves to the reservoir chamber through the expansion side restricting hole, and the damping force on the expansion side due to the resistance applied to the flow of the liquid is increased. appear. On the contrary, when the front fork contracts, the liquid in the pressure side chamber moves to the reservoir chamber through the pressure side throttle hole, and a pressure side damping force is generated due to the resistance applied to the flow of the liquid.

JP-A-9-217780

  However, when the damping force is generated using the throttle hole as in a conventional upright front fork, it is difficult to tune the damping force, for example, to make the damping force characteristic dependent on speed.

  That said, in the tube member, a cylinder, a piston that is slidably inserted into the cylinder and divides the cylinder into an extension side chamber and a pressure side chamber, and is connected to the piston and protrudes out of the cylinder. A damper cartridge is provided that includes a piston rod, a passage communicating the extension side chamber and the pressure side chamber, and a damping valve that opens and closes the passage and provides resistance to the flow of liquid passing through the passage. If this occurs, the number of parts of the front fork will increase and the cost will rise dramatically.

  Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide a front fork that can easily tune a damping force and reduce an increase in cost.

  The front fork that solves the above problems is a tube member having an outer tube on the wheel side and an inner tube on the vehicle body side, a rod connected to the outer tube, and a sliding contact with the inner periphery of the inner tube connected to the rod. A partition member that divides the inside of the tube member into a reservoir chamber and a liquid chamber, a passage that is formed in the partition member and communicates the reservoir chamber and the liquid chamber, opens and closes the passage, and resists the flow of liquid that passes through the passage. A damping valve is provided.

  According to the above configuration, the inner tube enters and exits the liquid chamber when the front fork extends and contracts. Then, the liquid corresponding to the volume of the inner tube that enters and exits the liquid chamber passes through the attenuation valve and moves between the liquid chamber and the reservoir chamber, and resistance is applied to the flow of the liquid by the attenuation valve. For this reason, a differential pressure is generated between the liquid chamber and the reservoir chamber when the front fork is expanded and contracted, and a damping force that prevents the expansion and contraction operation is generated.

  Thus, according to the above configuration, the damping force can be generated by using the damping valve that opens and closes, so that the tuning of the damping force can be facilitated. Furthermore, according to the above configuration, even if the damping force is easily tuned, at least the cylinder of the damper cartridge can be omitted as compared with the case where the damper cartridge is provided in the tube member, so that an increase in cost can be reduced.

  In the front fork, the damping valve has an extension side damping valve that opens and resists the flow of liquid from the reservoir chamber to the liquid chamber when extended, and the liquid flow that opens from the liquid chamber to the reservoir chamber when contracted. It is desirable to have a pressure-side damping valve that provides resistance. According to this configuration, tuning of the damping force on the expansion side and tuning of the damping force on the compression side can be performed independently, so that tuning of the damping force on both sides of the compression can be easily performed.

  In the front fork, it is preferable that an extension side check valve that opens when extended and a pressure side check valve that opens when contracted are provided in series with the damping valve. According to this configuration, since the number of elements (tuning elements) for tuning the damping force increases, the tuning of the damping force can be further facilitated.

  The front fork may include a fall prevention member that is connected to the upper side of the partition wall member of the rod and that can slide on the inner periphery of the inner tube. According to this configuration, the rod can be prevented from falling.

  In the front fork, the falling prevention member includes an annular bottom portion and a cylindrical portion that rises upward from the outer peripheral portion of the bottom portion, and the compression side check valve is stacked on the upper side of the bottom portion, and the extension side check The valve is preferably formed in an annular shape and attached to the outer periphery of the cylindrical portion.

  According to the above configuration, even if the fall prevention member is provided on the upper side of the partition wall member, the fall prevention member can be prevented from hindering communication between the passage provided in the partition wall member and the reservoir chamber. Furthermore, even if the check valve is attached to the fall prevention member, the configuration of the fall prevention member can be simplified, and the inside of the cylinder portion can be used as a storage space for the pressure side check valve.

  According to the front fork of the present invention, the damping force can be easily tuned, and the increase in cost can be reduced.

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 cross-sectional view of the front fork which concerns on one embodiment of this invention. It is the longitudinal cross-sectional view which expanded and showed a part of FIG.

  A front fork according to an embodiment of the present invention will be described below with reference to the drawings. The same reference numerals used throughout the several drawings indicate the same parts. In addition, the top and bottom 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 that suspends a front wheel W in a straddle-type vehicle V. A straddle-type vehicle is a 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 straddle-type vehicle.

  Next, a specific structure of the front fork F according to the embodiment of the present invention will be described. The front fork F includes a telescopic tube member T that includes an outer tube 1 and an 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 through 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 the upper end portion thereof.

  Thus, the front fork F is disposed with the outer tube 1 facing the front wheel (wheel) W and the inner tube 2 facing the vehicle body B, and is interposed between the vehicle body B and the axle of the front wheel W. . When the straddle-type vehicle V runs on an uneven road surface and the front wheel W vibrates up and down, the inner tube 2 enters and exits the outer tube 1 and the front fork F expands and contracts.

  As shown in FIG. 2, the inner tube 2 is slidably inserted into the outer tube 1 via a pair of bearings 10 and 20. In the present embodiment, one bearing 10 is held on the inner periphery of the upper end portion of the outer tube 1 and is in sliding contact with the outer periphery of the inner tube 2, and the other bearing 20 is held on the outer periphery of the lower end portion of the inner tube 2. In sliding contact with the inner circumference of However, both the bearings 10 and 20 may be held on one side of the outer tube 1 or the inner tube 2.

  Further, 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, and the lower opening of the outer tube 1 is closed by the bottom 1a. Further, an overlapping portion between the outer tube 1 and the inner tube 2 is closed by an oil seal 11 and a dust seal 12. In this way, the inside of the tube member T is a sealed space, and liquid and gas are sealed in the tube member T.

  Further, the rod 3 is connected to the bottom 1 a of the outer tube 1 by a bolt 30. This rod 3 stands up along the axial direction at the center of the outer tube 1, and the tip is inserted inside the inner tube 2. And the stopper member 31, the partition member 4, and the fall prevention member 5 are mounted | worn in order from the lower side at the front-end | tip part outer periphery of the rod 3. As shown in FIG.

  Further, the lower end of the inner tube 2 inserted into the outer tube 1 is positioned at least below the stopper member 31, and a spring receiving member 21 that supports the extending spring 6 is provided at the lower end portion of the inner tube 2. It is attached. The extending spring 6 is compressed between the spring receiving member 21 and the stopper member 31 when the front fork F is extended to alleviate the impact at the time of maximum extension.

  The stopper member 31 is formed with a communication hole 31 a that communicates the upper and lower sides of the stopper member 31 so that the stopper member 31 does not hinder the flow of the liquid moving in the inner tube 2.

  In addition, although the extending spring 6 of this Embodiment is a coil spring, springs other than a coil spring may be sufficient. Further, the stopper member 31 may be eliminated and the extending spring 6 may be abutted against the partition member 4. Further, a cushion rubber or the like may be provided in place of the extending spring 6, and the impact at the time of the maximum extension of the front fork F may be mitigated by this cushion rubber.

  The lower end portion of the spring receiving member 21 constitutes a lock piece together with the lower end portion of the inner tube 2. Further, a cylindrical lock case 13 stands on the bottom 1 a of the outer tube 1, and a lock piece is inserted between the lock case 13 and the outer tube 1 when the front fork F is contracted most. Thereby, the chamber on the outer peripheral side of the lock case 13 is closed with the lock piece, the hydraulic pressure lock is applied, and the impact when the front fork F is contracted is alleviated.

  A suspension spring S is laminated on the upper side of the fall prevention member 5. 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. As described above, since the fall prevention member 5 is attached to the rod 3 and the cap is attached to the inner tube 2, the suspension spring S of the present embodiment is provided between the rod 3 and the inner tube 2. It can be said that it is intervened in.

  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. Thus, the suspension spring S exhibits an elastic force commensurate with the amount of compression, and urges the front fork F in the extending direction to elastically support the vehicle body B.

  Note that the arrangement of the suspension springs S is not limited to the illustration 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, although the suspension spring S of the present embodiment is a coil spring, it may be a spring other than a coil spring such as an air spring.

  Subsequently, the partition member 4 is in sliding contact with the inner periphery of the inner tube 2 and partitions the tube member T into a reservoir chamber R and a liquid chamber L. The liquid chamber L is formed below the partition wall member 4, and the liquid chamber L is filled with a liquid such as hydraulic oil. On the other hand, the reservoir chamber R is formed on the upper side of the partition member 4, and the reservoir chamber R stores the same liquid as the liquid chamber L, and a gas such as air is sealed above the liquid surface. ing.

  In FIG. 2, a seal ring 40 is attached to the outer periphery of the partition member 4, and the partition member 4 is in sliding contact with the inner periphery of the inner tube 2 through the seal ring 40. However, it is needless to say that the seal ring 40 may be eliminated and the partition member 4 may be directly slidably contacted with the inner periphery of the inner tube 2.

  The partition member 4 is formed with an extension side and pressure side passages 4a and 4b penetrating the partition member 4 up and down, and an extension side for opening and closing the outlets of the extension side and the pressure side passages 4a and 4b, respectively. Pressure-side damping valves 41 and 42 are stacked. The expansion side and compression side damping valves 41 and 42 each have one or more leaf valves, and are laminated on the upper side or lower side of the partition wall member 4 in a state where the outer peripheral side is allowed to bend. Yes.

  More specifically, the extension-side damping valve 41 is stacked on the lower side (liquid chamber L side) of the partition member 4. When the front fork F is extended, the extension side damping valve 41 is bent to open the outer peripheral portion downward, and the extension side passage 4a is made to flow into the liquid chamber L from the reservoir chamber R. Give resistance. On the contrary, when the front fork F is contracted, the expansion-side damping valve 41 is kept closed.

  On the other hand, the pressure-side damping valve 42 is stacked above the partition wall member 4 (on the reservoir chamber R side). When the front fork F contracts, the pressure-side damping valve 42 is opened by bending the outer peripheral portion thereof upward, and provides resistance to the flow of liquid from the liquid chamber L toward the reservoir chamber R through the pressure-side passage 4b. . On the other hand, when the front fork F is extended, the compression side damping valve 42 is kept closed.

  Subsequently, the fall prevention member 5 provided on the upper side of the partition wall member 4 is in sliding contact with the inner periphery of the inner tube 2 when the rod 3 is inclined in the tube member T, and the rod 3 is further inclined (falls). To prevent. Further, the fall prevention member 5 includes an extension-side check valve 50 that allows only the flow of liquid from the reservoir chamber R to the partition member 4 side, and only the flow of liquid from the partition member 4 side to the reservoir chamber R. An allowable pressure-side check valve 51 is mounted.

  For this reason, even if the fall prevention member 5 is provided on the upper side of the partition member 4, the fall prevention member 5 does not hinder communication between the passages 4 a and 4 b provided in the partition member 4 and the reservoir chamber R. That is, if the gap formed between the partition wall member 4 and the fall prevention member 5 is an intermediate chamber M, the intermediate chamber M becomes a part of the passage that connects the passages 4a, 4b and the reservoir chamber R. Yes.

  In addition, as shown in FIG. 3, the fall prevention member 5 of the present embodiment includes an annular bottom portion 5 a and a cylindrical portion 5 b that rises upward from the outer periphery of the bottom portion 5 a. The bottom portion 5a is formed with a pressure side communication passage 5c penetrating the bottom portion 5a up and down, and the pressure side communication passage 5c is opened and closed by a pressure side check valve 51. On the other hand, an annular extending communication passage 5d that opens up and down is formed between the tube portion 5b and the inner tube 2, and the extending communication passage 5d is opened and closed by the extension check valve 50. Is done.

  The pressure-side check valve 51 is configured to include one or more leaf valves, and is stacked on the upper side of the bottom portion 5a in a state where the outer peripheral side is allowed to bend. When the pressure in the intermediate chamber M becomes higher than the pressure in the reservoir chamber R, the pressure side check valve 51 opens the pressure side communication path 5c by bending the outer peripheral portion thereof upward, and from the intermediate chamber M to the reservoir chamber R. Allow liquid flow towards. On the other hand, when the pressure in the reservoir chamber R is higher than the pressure in the intermediate chamber M, the pressure side check valve 51 is kept closed.

  On the other hand, the check valve 50 on the extension side is formed in an annular shape and is inserted into an annular groove 5e formed along the circumferential direction on the outer periphery of the cylindrical portion 5b, and is in sliding contact with the inner periphery of the inner tube 2. However, it can move up and down (in the axial direction) in the annular groove 5e.

  When the pressure in the intermediate chamber M becomes lower than the pressure in the reservoir chamber R, the check valve 50 on the expansion side moves downward in the annular groove 5e to open the communication passage 5d on the expansion side, and the reservoir chamber R Allows the liquid to flow toward the intermediate chamber M. On the other hand, when the pressure in the intermediate chamber M is higher than the pressure in the reservoir chamber R, the check valve 50 on the extension side moves upward in the annular groove 5e and sits on the fall prevention member 5 and is closed. Maintained.

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

  The inner tube 2 enters the liquid chamber L when the front fork F contracts so that the inner tube 2 enters the outer tube 1. During the contraction, the pressure-side damping valve 42 is opened, and the liquid corresponding to 2 volumes of the inner tube that has entered the liquid chamber L moves from the liquid chamber L to the intermediate chamber M through the pressure-side passage 4b. Then, the pressure side check valve 51 is opened, and the liquid in the intermediate chamber M is discharged to the reservoir chamber R.

  When the front fork F is contracted, a resistance is applied to the flow of liquid from the liquid chamber L toward the reservoir chamber R by the pressure-side damping valve 42. Therefore, when the front fork F is contracted, the pressure in the liquid chamber L is increased, a differential pressure is generated between the liquid chamber L and the reservoir chamber R, and a pressure-side damping force that prevents the contraction operation of the front fork F is generated. .

  On the contrary, when the front fork F is extended so that the inner tube 2 is withdrawn from the outer tube 1, the inner tube 2 is withdrawn from the liquid chamber L. At the time of extension, the extension-side attenuation valve 41 is opened, and the volume of the inner tube 2 volume that has retreated from the liquid chamber L moves from the intermediate chamber M to the liquid chamber L through the extension-side passage 4a. Then, the check valve 50 on the extension side is opened, and the liquid is supplied from the reservoir chamber R to the intermediate chamber M.

  When the front fork F is extended, resistance is applied to the liquid flow from the reservoir chamber R to the liquid chamber L by the extension-side damping valve 41. Therefore, when the front fork F is extended, the pressure in the liquid chamber L is reduced, a differential pressure is generated between the liquid chamber L and the reservoir chamber R, and an extension side damping force that prevents the front fork F from extending is generated. .

  Hereinafter, the effect of the front fork F according to the embodiment of the present invention will be described.

  The front fork F of the present embodiment includes a tube member T. The tube member T is a front wheel (wheel) W side outer tube 1 and a vehicle body B side that is slidably inserted into the outer tube 1. The inner tube 2 is provided.

  Further, the front fork F of the present embodiment includes a rod 3 coupled to the outer tube 1 and a sliding contact with the inner periphery of the inner tube 2 coupled to the rod 3 and the upper reservoir chamber R inside the tube member T. A partition member 4 partitioned into a liquid chamber L and a lower liquid chamber L, passages 4a and 4b formed in the partition member 4 to communicate the reservoir chamber R and the liquid chamber L, and the passages 4a and 4b are opened and closed. Damping valves 41 and 42 are provided to provide resistance to the flow of liquid passing through the passages 4a and 4b.

  According to the above configuration, the inner tube 2 enters and exits the liquid chamber L when the front fork F extends and contracts. Then, the liquid for 2 volumes of the inner tube entering and exiting the liquid chamber L passes between the attenuation valves 41 and 42 and moves between the liquid chamber L and the reservoir chamber R, and the attenuation valve 41 against the flow of the liquid. , 42 provide resistance. For this reason, a differential pressure is generated between the liquid chamber L and the reservoir chamber R when the front fork F is expanded and contracted, and a damping force that prevents the expansion and contraction operation is generated.

  As described above, when the damping force is generated using the damping valves 41 and 42 that are opened and closed when the front fork F is expanded and contracted, the damping force is reduced as compared with the conventional case where the damping force is generated using the throttle hole. Power tuning can be done easily. Specifically, the opening area of the damping valves 41 and 42 can be gradually increased as the expansion / contraction speed of the front fork F increases. Therefore, the characteristics of the generated damping force can be proportional to the speed.

  In addition, if an orifice that connects the liquid chamber L and the reservoir chamber R with the damping valves 41 and 42 closed is formed, the expansion / contraction speed of the front fork F is low and the damping valves 41 and 42 are not opened at a low speed range. The damping force characteristic can be made a square characteristic by the orifice, and the damping force characteristic in the middle and high speed range where the damping valves 41 and 42 are opened can be made a proportional characteristic.

  That is, according to the above configuration, tuning of the damping force such as making the damping force characteristic dependent on speed is easy. Even if the damping force can be easily tuned in this way, according to the above configuration, at least the cylinder of the damper cartridge can be omitted as compared with the case where the damper cartridge is provided in the tube member T. Can be reduced.

  Further, when a leaf valve is used as the valve body of the damping valves 41 and 42 as in the present embodiment, the leaf valve is a thin annular plate, so it is not bulky in the axial direction, and the axial length of the rod 3 is shortened. it can. Furthermore, the damping force can be tuned by changing the leaf valve thickness, diameter, number of stacked layers, and the like.

  However, the configuration of the damping valves 41 and 42 only needs to be able to open and close the passages 4a and 4b when the front fork F is expanded and contracted, and the configuration of the valve body that opens and closes the passages 4a and 4b is not limited to the leaf valve. For example, a poppet valve that is biased in the closing direction by a biasing spring may be used as the valve body of the damping valves 41 and 42. In such a case, the damping force can be tuned by changing the initial load applied to the poppet valve or by using an urging spring having a different spring constant.

  Further, the damping valves 41 and 42 of the present embodiment include an extension-side damping valve 41 that opens when the front fork F extends and provides resistance to the flow of liquid from the reservoir chamber R to the liquid chamber L, and the front fork F. There is a pressure-side damping valve 42 that opens when the liquid is contracted and provides resistance to the flow of liquid from the liquid chamber L toward the reservoir chamber R. According to this configuration, tuning of the damping force on the expansion side and tuning of the damping force on the compression side can be performed independently, so that tuning of the damping force on both sides of the compression can be easily performed.

  However, for example, even when a damping valve for one of the pressure expansions is provided, at least one of the damping force for the pressure expansion can be easily tuned. Such a change is possible regardless of the configuration of the damping valves 41 and 42.

  Further, the front fork F of the present embodiment includes an extension side check valve 50 that opens when the front fork F extends, and a pressure side check valve 51 that opens when the front fork F contracts, and these are arranged in series with the damping valves 41 and 42. . According to this configuration, since the number of elements (tuning elements) for tuning the damping force increases, the tuning of the damping force can be further facilitated.

  In addition, the front fork F of the present embodiment includes a valve body member (falling prevention member) 5 that is connected to the upper side of the partition member 4 of the rod 3 and that can slide on the inner periphery of the inner tube 2. . For this reason, falling of the rod 3 can be prevented.

  Furthermore, the valve body member (falling prevention member) 5 of the present embodiment includes an annular bottom portion 5a and a cylindrical portion 5b that rises upward from the outer peripheral portion of the bottom portion 5a. A pressure-side check valve 51 is stacked above the bottom 5a. On the other hand, the check valve 50 on the extended side is formed in an annular shape and attached to the outer periphery of the cylindrical portion 5b.

  Thus, in this embodiment, the check valve 50, 51 on the extension side and the pressure side is provided on the fall prevention member 5 for preventing the rod 3 from falling. For this reason, even if the fall prevention member 5 is provided on the upper side of the partition wall member 4, the fall prevention member 5 can be prevented from hindering communication between the passages 4 a and 4 b provided in the partition wall member 4 and the reservoir chamber R.

  Further, according to the above configuration, the extension side check valve 50 is provided on the outer periphery of the cylindrical portion 5b, and the pressure side check valve 51 is provided on the bottom portion 5a. For this reason, for example, compared with the case where both the valve body of the check valve 50 on the extension side and the valve body of the check valve 51 on the pressure side are leaf valves and stacked on the top and bottom of the bottom portion 5a, the extension side and the pressure side are connected. The structure for making the passages 5c and 5d independent and one-way can be simplified, and the structure of the fall prevention member 5 can be simplified.

  Further, according to the above configuration, the pressure-side check valve 51 is stacked on the upper side of the bottom portion 5a, and is disposed on the inner side of the cylindrical portion 5b that rises upward from the outer peripheral portion of the bottom portion 5a. Thus, according to the said structure, the inner side of the cylinder part 5b can be utilized as an accommodation space of the check valve 51 of the compression side.

  However, the pressure-side check valve 51 may be annularly attached to the outer periphery of the cylindrical portion 5b, and the extension-side check valve 50 may be stacked below the bottom portion 5a. Alternatively, the extension side and pressure side check valves may be attached to the bottom portion 5 a so that the fall prevention member 5 is always in sliding contact with the inner periphery of the inner tube 2. In such a case, the fitting length between the inner tube 2 and the rod 3 can be increased.

  Furthermore, the check valves 50 and 51 on the extension side and the pressure side may be eliminated, and a communication hole that allows a bidirectional flow by penetrating the fall prevention member vertically may be provided, or the fall prevention member itself may be eliminated. . These changes can be made regardless of the configuration of the damping valves 41 and 42, as well as in the case where one damping valve is provided for pressure expansion.

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

B ... Vehicle body, F ... Front fork, L ... Liquid chamber, R ... Reservoir chamber, T ... Tube member, W ... Front wheel (wheel), 1 ... Outer tube, 2 ... inner tube, 3 ... rod, 4 ... partition member, 4a ... extension side passage (passage), 4b ... pressure side passage (passage), 5 ... fall prevention member 5a ... bottom part, 5b ... cylinder part, 41 ... extension side damping valve (attenuation valve), 42 ... compression side damping valve (attenuation valve), 50 ... extension side check valve 51 ... Pressure side check valve

Claims (5)

A tube member having a wheel side outer tube and a vehicle body side inner tube slidably inserted into the outer tube;
A rod connected to the outer tube;
A partition member connected to the rod and in sliding contact with the inner periphery of the inner tube, and dividing the inside of the tube member into an upper reservoir chamber and a lower liquid chamber;
A passage formed in the partition member and communicating the reservoir chamber and the liquid chamber;
A front fork comprising: a damping valve that opens and closes the passage and provides resistance to a flow of liquid passing through the passage. The damping valve includes an expansion-side damping valve that opens when extended and provides resistance to the flow of liquid from the reservoir chamber toward the liquid chamber, and a flow of liquid that opens when contracted and flows from the liquid chamber toward the reservoir chamber. The front fork according to claim 1, further comprising a pressure-side damping valve that provides resistance. 3. The front fork according to claim 1, wherein an extension side check valve that opens when extended and a pressure side check valve that opens when contracted are provided in series with the damping valve. 4. The fall prevention member connected to the upper side of the partition member of the rod and capable of sliding contact with the inner periphery of the inner tube is provided. 5. Front fork. The fall-preventing member includes an annular bottom portion and a cylindrical portion that rises upward from the outer peripheral portion of the bottom portion,
The pressure side check valve is laminated on the upper side of the bottom part,
The front fork according to claim 4, which is dependent on claim 3, wherein the check valve on the extension side is formed in an annular shape and is attached to an outer periphery of the cylindrical portion.

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