JP2011122699A - Air valve mounting structure in shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air valve mounting structure housing an air valve in a cap member, and preventing air leakage. <P>SOLUTION: The shock absorber includes a tube (a fork body F), an air chamber A formed in the tube, the cap member 3 facing the air chamber A and blocking one end of the tube, and the air valve 4 provided in the cap member 3 and carrying out supply and discharge of air in the air chamber A. The air chamber A seals air in an interior and functions as an air spring, and spring force of the air spring can be adjusted via the air valve 4. The cap member 3 has a through-hole 30 in an axial direction, and the air valve 4 is screwed from an air chamber side and housed in the hole 30. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an air valve mounting structure in a shock absorber, and more particularly, to an improvement in an air valve mounting structure that houses an air valve in a cap member.

  The shock absorber provided with the air valve mounting structure is embodied in a front fork as shown in Patent Document 1, for example.

  The front fork is provided with an air chamber in which air is sealed above the vehicle body side tube to perform an air spring function, and the upper end of the vehicle body side tube is closed by a cap member.

  The cap member is provided with an air valve for supplying and exhausting air to and from the air chamber so that the air pressure in the air chamber can be adjusted.

  The front fork is useful in that the air valve can be adjusted to any air spring force of the driver by changing the air pressure by providing the air valve. However, the air valve protrudes from the cap member, so that the air valve is damaged. Reinforcing is required to prevent the appearance, and the appearance performance is inferior.

  In view of this, an air valve mounting structure has been proposed in which the air valve is accommodated in a cap member and the above problems can be improved.

  As shown in FIG. 4, the air valve mounting structure is provided with a hole 30A penetrating in the axial direction in the cap member 3A, and the air valve 4A is screwed into the hole 30A from the side opposite to the vehicle body side tube 1 side.

Japanese Patent Laid-Open No. 11-257401

  The proposed air valve mounting structure is useful in that the problem in Patent Document 1 can be solved, but further improvement is desired.

  That is, in the proposed air valve mounting structure, the air valve 4A is screwed into the air chamber A, but the air chamber A is compressed when the front fork contracts, and the air chamber A becomes high pressure. There is a possibility that the air valve 4A is biased in the direction in which the air valve 4A is pulled out by the air pressure, and the air valve 4A is loosened to cause air leakage.

  Therefore, the present invention was created in view of such a current situation, and an object of the present invention is to provide an air valve mounting structure in a shock absorber capable of accommodating an air valve in a cap member and preventing air leakage. Is to provide.

  Means for solving the above problems are a tube, an air chamber formed in the tube, a cap member that opposes the air chamber and closes one end of the tube, and the cap member is provided with the cap member. An air valve for supplying and discharging air to and from the air chamber, wherein the air chamber functions as an air spring with air enclosed therein, and the cap member is capable of adjusting the spring force of the air spring via the air valve. Has a hole penetrating in the axial direction, and the air valve is accommodated in the hole while being screwed from the air chamber side.

  According to the present invention, the air valve can be accommodated in the cap member, and the air valve is screwed into the hole of the cap member from the air chamber side, thereby preventing the air valve from loosening and preventing air leakage. Is possible.

It is a fragmentary longitudinal cross-sectional view which partially fractures | ruptures and shows the front fork which is a shock absorber provided with the air valve attachment structure which concerns on one embodiment of this invention. It is a partial expanded longitudinal cross-sectional view which partially fractures | ruptures and shows the front fork which is a shock absorber provided with the air valve attachment structure which concerns on one embodiment of this invention. It is a partial expanded longitudinal cross-sectional view which shows the piston peripheral part of the front fork which is a shock absorber provided with the air valve attachment structure which concerns on one embodiment of this invention. It is a partial expanded longitudinal cross-sectional view which shows partially the front fork which is a shock absorber provided with the conventional air valve attachment structure, and is shown.

  Hereinafter, an air valve mounting structure in a shock absorber according to an embodiment of the present invention will be described with reference to the drawings. The same reference numerals given throughout the several drawings indicate the same or corresponding parts.

  An air valve mounting structure in a shock absorber according to an embodiment of the present invention is embodied in, for example, a front fork that functions as a hydraulic shock absorber that damps road surface vibration input to a front wheel of a two-wheeled vehicle while suspending the front wheel. .

  The front fork is composed of a pair of fork main bodies F, F standing on the left and right of the front wheel. The fork main body F is a vehicle body side tube 1 and a wheel that is slidably fitted into the vehicle body side tube 1. It consists of a side tube 2.

  As shown in FIG. 1, the air valve mounting structure in the present embodiment includes a tube, that is, a fork main body F composed of a vehicle body side tube 1 and a wheel side tube 2, and an air chamber A formed in the fork main body F. The cap member 3 is configured to oppose the air chamber A and closes one end of the fork main body F, and the air valve 4 is provided on the cap member 3 to supply and discharge air into the air chamber A.

  The air chamber A functions as an air spring with air enclosed therein, and the air spring force can be adjusted by supplying and discharging air into the air chamber A through the air valve 4.

  The cap member 3 has a hole 30 penetrating in the axial direction, and the air valve 4 is accommodated in the hole 30 while being screwed from the air chamber side, that is, the fork main body side.

  By providing the hole 30, the air valve 4 can be accommodated in the cap member 3, and the air valve 4 can be prevented from loosening to prevent air leakage.

  Below, each component of the attachment structure of the air valve in this Embodiment is each demonstrated.

  As shown in FIG. 1, the pair of left and right fork bodies F, F in the front fork are respectively a vehicle body side tube 1 coupled to the vehicle body side via a bracket (not shown), and a bottom member 20 on the wheel side. The wheel-side tube 2 is coupled via a so-called inverted front fork.

  And since the said wheel side tube 2 can be projected and retracted in the vehicle body side tube 1, making the outer periphery slidably contact with the inner periphery of the vehicle body side tube 1, the fork main body F can expand and contract by receiving road surface vibration. Become.

  The fork main body F accommodates a damper D that attenuates the expansion and contraction movement of the fork main body F and a suspension spring S that urges the fork main body F in the extending direction.

  In addition, a reservoir R is formed between the fork main body F and the damper D. The reservoir R has an air chamber A located above the oil level (not shown) and a lower side. The oil chamber O is located.

  The fork main body F is sealed with the cap member 3 at the upper end of the fork main body F and the bottom member 20 at the lower end, thereby maintaining the sealed state in the fork main body F and supplying air into the air chamber A. It can be sealed to function as an air spring.

  The cap member 3 is provided with an air valve 4, and by adjusting the air pressure in the air chamber A via the air valve 4, a desired air spring force can be obtained.

  The suspension spring S accommodated in the fork main body F has an upper end locked to the vehicle body side tube 1 via the spacer S1, and a lower end locked to the bottom member 20 via the cylinder 5 of the damper D. With this configuration, the fork body F is urged in the extension direction by pressing the vehicle body side tube 1 upward and the wheel side tube 2 downward.

  The spacer S1 is formed in a cylindrical shape, and has a screw groove (not shown) on the upper outer periphery in the drawing, and is screwed to the upper end opening of the vehicle body side tube 1 via a seal member C1. Become.

  Further, as shown in FIG. 2, the cap member 3 is screwed to the inner periphery of the spacer S1 via a seal member (not shown). That is, the upper end of the vehicle body side tube 1 can be closed.

  The cap member 3 has a through hole 31 penetrating the shaft center part and a hole 30 penetrating in the axial direction avoiding the through hole 31, and the air valve 4 is screwed into the hole 30 from the fork main body side. Contained while wearing.

  Since the air valve 4 is screwed from the air chamber side toward the anti-fork main body side, even when the fork main body F is contracted, the air valve 4 is moved to the anti-fork main body side, that is, the air valve by the high air chamber A. Since 4 is urged in the screwing direction, the air valve is not loosened, and air leakage can be prevented.

  The hole 30 for accommodating the air valve 4 includes a screw hole 30a on the fork main body side, a large-diameter hole 30b extending from the screw hole 30a to the side opposite to the air chamber and having a larger diameter than the screw hole 30a. The air valve 4 is screwed into the screw hole 30a and has a tip projecting into the large-diameter hole 30b, and a valve cap 40 is screwed onto the outer periphery of the tip.

  By providing the valve cap 40, it is possible to prevent air from leaking due to a pin (not shown) of the air valve 4 being pushed.

  Further, according to the above configuration, the valve cap 40 can be screwed to the air valve 4 using the screw groove for screwing into the screw hole 30a. There is no need to provide it, and the processing cost of the air valve 4 can be reduced.

  The air valve 4 accommodated in the hole 30 includes a cylindrical housing 41 and a valve main body 42 that is accommodated in the housing 41 and supplies and discharges air into and from the air chamber A. An attachment groove 43 formed on the inner periphery of the fork main body is provided.

  The space formed by the mounting groove 43 is formed in a hexagonal column shape, and the air valve 4 can be rotated by engaging a tool such as a hexagonal bar wrench having a hexagonal columnar tip shape with the mounting groove 43.

  That is, when the air valve is rotated by locking a tool or the like on the outer periphery as in the prior art, it is necessary to secure an engagement space for the tool or the like in the hole 30, but according to the configuration including the mounting groove 43, It is possible to attach the air valve 4 in a narrow space without requiring the above-mentioned locking space.

  Accordingly, it is possible to prevent the vehicle body side tube 1 from increasing in diameter due to the increase in the diameter of the cap member 3, and thus it is possible to reduce the weight and cost of the front fork.

  The shape of the mounting groove 43 is not limited to the above, and can be appropriately selected according to the shape of the tool used for mounting the air valve 4. For example, the tool and the mounting groove 43 include a key and a key groove. If it is in the relationship, it is possible to achieve the above-mentioned effect by the mounting groove 43.

  As shown in FIG. 1, a damper D that attenuates the expansion and contraction movement of the fork main body F includes a rod 6 whose base end is fixed to the cap member 3, and a rod 6 that is freely inserted and retracted so that hydraulic oil is inserted thereinto. And a piston 7 which is provided on the distal end side of the rod 6 and divides the inside of the cylinder 5 into two pressure chambers R1 and R2.

  As shown in FIG. 3, the piston 7 provides ports P1 and P2 communicating with the two pressure chambers R1 and R2, and gives a flow resistance when hydraulic oil passes through the ports P1 and P2. Damping force generating means V1 and V2 comprising leaf valves for generating the above damping force are provided.

  The rod 6 that holds the piston 7 at the distal end includes a through hole 6a that passes through the axial center portion and communicates with the through hole 31 of the cap member 3, and a damping force adjusting means to be described later in the through hole 6a. The needle valve 8 and the push rod 9 constituting the above are accommodated so as to be movable in the axial direction.

  A cylinder 5 in which the rod 6 protrudes and retracts is fixed to the wheel-side tube 2 via a bottom member 20, and a sealing member (not shown) that closes the upper end while allowing the rod 6 to slide, and a lower end A bottom valve (not shown) that is provided and supplements the working fluid that is excessive or insufficient as the rod 6 protrudes and retracts from the oil chamber O of the reservoir R is provided.

  By providing the above configuration, the damper D forms a body of a double cylinder type hydraulic shock absorber, and can generate a predetermined damping force as the fork main body F expands and contracts.

  The configuration of the damper D is not limited to the above, and the configuration can be selected as appropriate.

  The damping force adjusting means for adjusting the damping force in the damper D bypasses the damping force generating means V1 and V2 and communicates with the two pressure chambers R1 and R2, and moves forward and backward in the bypass path B. The needle valve 8 that changes the opening amount thereof, the adjuster 10 that moves the needle valve 8 forward and backward, and the needle valve 8 that is provided between the needle valve 8 and the adjuster 10 has an action from the adjuster 10. It consists of the push rod 9 that transmits.

  The push rod 9 is always in contact with the adjuster 10 via a biasing spring S2 that biases the needle valve 8 upward in the drawing.

  By providing the above configuration, the opening amount of the bypass passage B is changed according to the amount of the needle valve 8 entering the bypass passage B, and the flow rate of the hydraulic oil passing through the damping force generating means V1 and V2 is changed. Thus, the damping force of the front fork can be adjusted in height.

  As shown in FIG. 2, the adjuster 10 is provided in a through hole 31 of the cap member 3. The adjuster 10 is inserted into the through hole 31 to be formed into a cylindrical shape and has a groove along the inner periphery in the axial direction (FIG. (Not shown), a adjuster body 12 provided in the case 11 and having a distal end abutting against the proximal end of the push rod 9, and an energizing member provided between the adjuster body 12 and the case 11. A detent ball 13 pressed against the groove of the case 11 via a spring (not shown), and a seal member (not shown) that seals between the adjuster body 12 and the case 11 and the through hole 31; Configure the detent mechanism.

  The tip of the adjuster body 12 is screwed into the through-hole 31, and the adjuster body 12 is rotated so that the tip of the adjuster body 12 appears and disappears in the through hole 6a.

  By providing the above configuration, the needle valve 8 is moved in the axial direction in the through hole 6a via the push rod 9 as the adjuster body 12 rotates, thereby changing the opening amount of the bypass passage B and adjusting the damping force. It becomes possible.

  Although the adjuster 10 is provided with the detent structure, the adjuster body 12 can be prevented from rotating without input of external force. However, it is possible to select an appropriate configuration such as a simple screw type.

  For example, although not shown, the push rod 9 may be moved by using the adjuster 10 as an actuator composed of a motor or a solenoid.

  Further, it is not always necessary to provide the damping force adjusting means. However, when the rod 6 is coupled to the cap member 3 or the adjuster 10 is provided as in the present embodiment, the air valve 4 is particularly attached. Therefore, it is more effective to use the air valve 4 provided with the mounting groove 43.

  While the preferred embodiment of the present invention has been described above, it should be understood that modifications, variations and changes may be made without departing from the scope of the claims.

  For example, in the above-described embodiment, an inverted front fork is employed, but this is not a limitation, and it goes without saying that an upright front walk may be used.

  In the present embodiment, the left and right fork bodies F, F have been described as the same front fork. However, the present invention is not limited to this, and it is a matter of course that both may have different configurations. Only the configuration according to the present invention may be embodied.

  In addition, the air valve mounting structure according to the present invention may be used for a shock absorber other than the front fork. For example, although not shown, it can of course be embodied in a rear cushion unit or another shock absorber.

A Air chamber B Bypass path D Damper F Fork body O Oil chamber R Reservoir R1, R2 Pressure chamber S Suspension spring S1 Spacer S2 Energizing spring 1 Car body side tube 2 Wheel side tube 3 Cap member 4 Air valve 5 Cylinder 6 Rod 7 Piston 8 Needle valve 9 Push rod 10 Adjuster 30 Hole 30a Screw hole 30b Large diameter hole 31 Through hole 40 Valve cap 41 Housing 42 Valve body 43 Mounting groove

Claims (4)

A tube, an air chamber formed in the tube, a cap member that opposes the air chamber and closes one end of the tube, and an air valve that is provided in the cap member and supplies and discharges air into the air chamber. In the shock absorber, the air chamber is filled with air and functions as an air spring, and the spring force of the air spring can be adjusted via the air valve.
An air valve mounting structure in a shock absorber, wherein the cap member has a hole penetrating in an axial direction, and the air valve is housed in the hole while being screwed from the air chamber side.   The air valve includes a cylindrical housing and a valve body accommodated in the housing. The housing includes a mounting groove formed on the inner periphery of the air chamber side, and the air valve is rotated using the mounting groove. The air valve mounting structure for a shock absorber according to claim 1, wherein the air valve is accommodated while being screwed into the hole.   The hole comprises a screw hole and a large-diameter hole extending from the screw hole to the side opposite the air chamber and having a larger diameter than the screw hole. The air valve is screwed into the screw hole and The air valve mounting structure for a shock absorber according to claim 1 or 2, wherein a tip end portion projects into the diameter hole, and a valve cap is screwed onto the tip end portion. A fork main body comprising a vehicle body side tube and a wheel side tube slidably fitted in the vehicle body side tube; a damper which is accommodated in the fork main body and generates a predetermined damping force; and the damping force Damping force adjusting means for adjusting, a reservoir formed between the fork main body and the damper and comprising an upper air chamber and a lower oil chamber, and the upper end of the fork main body being closed facing the air chamber A cap member and an air valve provided on the cap member for supplying and discharging air into the air chamber. The air is enclosed in the air chamber and functions as an air spring. The spring force of the air spring is transmitted through the air valve. In a shock absorber consisting of an adjustable front fork,
The cap member has a through hole penetrating the shaft center part and a hole penetrating in the axial direction while avoiding the through hole, and accommodates an adjuster constituting the damping force adjusting means in the through hole, and The air valve mounting structure in a shock absorber according to claim 2 or 3, wherein the air valve is housed in the hole while being screwed from the air chamber side.

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