JP2001241554A - Sealing device of shock-absorber for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device capable of reducing the number of parts and the assembly man-hour, in designing a mechanism of oil and dust-seal for an opening end of an outer-tube. SOLUTION: In a front fork 10 of a vehicle shock-absorber, this sealing device 13 is provided with a body 81A, an elastic member 81B, a joint 81C, and a retainer 81D. The device is also provided with an inner surface oil-seal lip 82 in the retainer 81D, an outer surface oil-seal lip 83 on outer surface in axial direction of the body 81A, and an inner surface dust-seal lip 84 on inner surface in axial direction of the body 81A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle shock absorber sealing device suitable for use in a front fork of a motorcycle or the like.

[0002]

2. Description of the Related Art Conventionally, as a sealing device for a front fork for a motorcycle, as disclosed in Japanese Patent Application Laid-Open No. 9-287665, an axially inner side of an oil seal case portion provided at an opening end of an outer tube into which an inner tube is inserted. An oil seal is mounted on the oil seal case, and a dust seal is mounted on the outside of the oil seal case in the axial direction. In this conventional technique, the engaging portion formed on the main body portion (metal reinforcing ring) of the dust seal is engaged with the concave groove provided on the oil seal case portion, so that the dust seal does not detach from the oil seal case portion. Can be fixed. Further, the oil seal is pressed from above by the dust seal, and the oil seal can be fixed without using a fixing member such as a stopper ring.

[0003]

However, in the prior art, the dust seal and the oil seal are separate parts, and in this respect, the number of parts and the number of assembling steps are increased, so that the product cost is high.

[0004] It is an object of the present invention to reduce the number of parts and the number of assembling steps when installing an oil seal mechanism and a dust seal mechanism at the open end of an outer tube, thereby reducing product cost.

[0005]

According to a first aspect of the present invention, an inner tube is slidably inserted into an outer tube, and hydraulic oil is sealed inside the outer tube and the inner tube. A first large-diameter hole at an open end of the tube into which the inner tube is inserted, and a second large-diameter hole having an inner diameter larger than the first large-diameter hole provided outside the first large-diameter hole in the axial direction. A sealing device for a shock absorber for a vehicle, comprising a hole, a concave groove provided on an inner periphery of a second large-diameter hole, and mounted on the open end of the outer tube, comprising: an annular main body; An annular shape formed by bending a radially outward portion from the axially outer portion with the main body portion with a gap interposed therebetween and elastically expanding and contracting in the radial direction so as to fit into the second large-diameter hole. An elastic portion, an engaging portion bent radially outward from the elastic portion and capable of engaging with the concave groove, and an axial direction of the main body portion. A supporting portion of the annular and bent forming the inner portion on the inner peripheral side of the body portion, provided on the support portion, and the inner side oil seal lip in sliding contact with the outer periphery of the inner tube,
An outer peripheral oil seal portion fitted to the first large-diameter hole is provided on an outer peripheral portion on the inner side in the axial direction of the main body portion, and slides on an outer peripheral portion of the inner tube provided on an inner peripheral portion on the outer axial side of the main body portion. And an inner-peripheral-side dust seal lip portion in contact therewith.

According to a second aspect of the present invention, in addition to the first aspect of the present invention, there is further provided an outer peripheral side dust seal portion provided in an outer peripheral portion of the elastic portion and fitted to a second large-diameter hole. It is made to be.

According to a third aspect of the present invention, the inner tube is slidably inserted into the outer tube, and hydraulic oil is sealed inside the outer tube and the inner tube. The inner tube of the outer tube is inserted. A sealing device for a shock absorber for a vehicle, which is provided with a large-diameter hole and a concave groove provided on the inner periphery of the large-diameter hole at the open end to be attached to the open end of the outer tube. An annular main body, a notch formed radially outward from the main body, elastically expanding and contracting in the radial direction to engage with the concave groove, and an axial inner side of the main body. An annular support portion formed by bending a portion on the inner peripheral side of the main body portion; an inner peripheral side oil seal lip portion provided on the support portion for sliding contact with the outer periphery of the inner tube; and an outer peripheral portion of the main body portion in the axial direction. Outer peripheral side oil seal part fitted to the large diameter hole, Provided on the inner periphery of the axially outer, it is obtained by the so and an inner peripheral side dust seal lip portion in sliding contact with the outer periphery of the inner tube.

According to a fourth aspect of the present invention, in addition to the third aspect of the present invention, an outer peripheral side dust seal portion fitted to a large-diameter hole is provided on an outer peripheral portion of the main body portion on the outer side in the axial direction. It is intended to have.

The present invention according to claim 5 provides the invention according to claims 1-4.
In the present invention described in any one of the above, further, the support portion may bend the axially inner end of the main body portion so as to be in contact with the inner periphery of the main body portion, and the distal end portion of the bending may be radially inward. It is formed by bending.

The present invention described in claim 6 provides the invention according to claims 1-4.
In the present invention described in any one of the above, the support portion may be formed by bending an axially intermediate portion of the main body portion inward in the radial direction.

[0011]

According to the first aspect of the present invention, the following operations are provided. When a sealing device having an inner peripheral side oil seal lip portion, an outer peripheral side oil seal portion, and an inner peripheral side dust seal lip portion is attached to the open end of the outer tube, the engaging portion of the elastic portion is connected to the second portion of the outer tube. The engaging portion is slid into the second large-diameter hole to engage the concave groove with the elastic portion reduced in diameter against the large-diameter hole, and then the elastic portion is elastically restored to expand. By making the diameter smaller, the sealing device can be securely fixed from the opening end without using a fixing member such as a stopper ring.

Since the sealing device is provided with the inner peripheral oil seal lip, the outer peripheral oil seal, and the inner peripheral dust seal lip, the inner peripheral oil seal lip slides on the inner tube in a liquid-tight manner. The oil seal mechanism in which the side oil seal part is fitted in the first large-diameter hole of the outer tube in a liquid-tight manner and the dust seal mechanism in which the inner peripheral side dust seal part slides on the inner tube are not separated from each other.
The number of parts and assembly man-hours can be reduced, and product costs can be reduced.

According to the second aspect of the present invention, the following operations are provided. The sealing device also has an outer peripheral side dust seal portion, and the outer peripheral side dust seal portion can be integrally provided with a dust seal mechanism that slides on the second large-diameter hole of the outer tube.

According to the third aspect of the present invention, the following operations are provided. When mounting a sealing device having an inner peripheral side oil seal lip portion, an outer peripheral side oil seal portion, and an inner peripheral side dust seal lip portion on the open end of the outer tube, the engaging portion of the main body portion is applied to the large-diameter hole, In a state where the diameter is reduced, the engaging portion is slid into the large-diameter hole to engage with the concave groove, and then the engaging portion is elastically restored to expand the diameter. It can be firmly fixed by making it possible to prevent it from falling off from the opening end without using a fixing member such as.

Since the sealing device includes the inner peripheral side oil seal lip, the outer peripheral side oil seal and the inner peripheral side dust seal lip, the inner peripheral side oil seal lip slidingly contacts the inner tube in a liquid-tight manner, The number of parts and assembly are such that the oil seal mechanism where the side oil seal part fits into the large diameter hole of the outer tube in a liquid-tight manner and the dust seal mechanism where the inner peripheral side dust seal part slides on the inner tube do not become separate bodies. It can reduce man-hours and product cost.

According to the fourth aspect of the invention, the following effects are obtained. The sealing device also has an outer peripheral side dust seal portion, and the outer peripheral side dust seal portion can be integrally provided with a dust seal mechanism in which the outer peripheral side dust seal portion slides on a large-diameter hole of the outer tube.

According to the fifth aspect of the invention, the following operations are provided. In the sealing device, the support portion can be easily formed by bending the inner end in the axial direction of the main body.

According to the sixth aspect of the invention, the following operations are provided. In the sealing device, the support portion can be easily formed by bending the intermediate portion in the axial direction of the main body.

[0019]

FIG. 1 is an overall sectional view showing a front fork, FIG. 2 is an enlarged sectional view of a lower portion of the front fork,
3 is an enlarged cross-sectional view of the upper portion of the front fork, FIG. 4 is a cross-sectional view showing an enlarged sealing device provided at the open end of the outer tube, FIG. 5 is a cross-sectional view showing an enlarged portion of the hollow pipe, and FIG. Is a schematic view showing a manufacturing procedure of a piston portion of a hollow pipe, FIG. 7 is a schematic view showing an operation of a check valve of a piston portion of an inner tube, FIG. 8 is a cross-sectional view showing a first modification of the present invention, and FIG. It is sectional drawing which shows the 2nd modification of this invention.

Front fork 10 (vehicle shock absorber)
As shown in FIGS. 1 to 3, a vehicle body-side inner tube 12 is inserted into an outer tube 11 having one end closed and the other end opened on the wheel side, and both tubes 11, 12 can be slidably extended and contracted. And A sealing device 13 is attached to an open end of the outer tube 11 into which the inner tube 12 is inserted. The sliding structure of the outer tube 11 and the inner tube 12 and the configuration of the sealing device 13 will be described later in detail.

At the bottom of the outer tube 11, a bolt 2
1 is inserted, and the hollow pipe 22 is fixed by the bolts 21 and is erected inside the outer tube 11. The structure for fixing the hollow pipe 22 with the bolts 21 will be described later in detail. A suspension spring 24 is interposed between a later-described piston portion 32 of the hollow pipe 22 (or an upper end surface of the hollow pipe 22) and a spring seat 23 provided at an upper end portion of the inner tube 12. The spring seat 23 is sealed via an O-ring 25 to the inner diameter portion on the upper end side of the inner tube 12, and is held by a stopper ring 26.

A piston 31 facing the outer periphery of the hollow pipe 22 is held by caulking at the inner diameter of the lower end of the inner tube 12, and a piston 32 facing the inner periphery of the inner tube 12 is provided at the tip of the hollow pipe 22. Is provided.

In the front fork 10, the upper oil chamber 33 for generating a damping force during the extension stroke in which the inner tube 12 rises is constituted by the inner tube 12, the hollow pipe 22, the piston 31 and the piston 32. are doing. Further, the front fork 10 forms a lower oil chamber 34 between the outer tube 11 below the piston portion 31 and the hollow pipe 22, and forms a reservoir between the inner diameter of the hollow pipe 22 and the inner tube 12 communicating therewith. A plurality of through holes 36 communicating the lower oil chamber 34 and the reservoir chamber 35 are provided in the hollow pipe 22 as a chamber 35. The reservoir chamber 35 is filled with hydraulic oil, and FIG.
The oil level L in the state is shown. Inside the inner tube 12, the upper space of the reservoir chamber 35 is a gas chamber 37.

At this time, the piston portion 31 at the inner diameter of the other end of the inner tube 12 holds the valve housing 41 and the washer 42 by caulking the inner tube 12, and slides up and down inside the valve housing 41 against the hollow pipe 22. (A) The check valve 43 is moved upward during the compression stroke (the upper oil chamber 33 has a lower pressure than the lower oil chamber 34, and the inner tube 1 of the hollow pipe 22 has
(Upward movement relative to the upward movement relative to the second oil chamber 2) to allow the passage of oil from the lower oil chamber 34 to the upper oil chamber 33 by the upper end groove 43A of the check valve 43 (FIG. 7 (A)). In the extension stroke, the check valve 43 is moved downward (as the upper oil chamber 33 becomes high pressure and as the hollow pipe 22 moves downward relative to the inner tube 12), and the lower end face of the check valve 43 is washed. 42 to prevent the passage of oil from the upper oil chamber 33 to the lower oil chamber 34 (FIG. 7B). Further, the piston portion 32 of the hollow pipe 22 always blocks the passage of oil. The front fork 10 is provided with an orifice 38 communicating the upper oil chamber 33 and the reservoir chamber 35 in the hollow pipe 22, and the oil that moves from the upper oil chamber 33 to the reservoir chamber 35 using the orifice 38 during the extension stroke. , A damping force during the extension stroke is generated based on the passage resistance. The damping force generating means during the extension stroke may be provided in the piston portion 32.

In the front fork 10, a piston 31 provided on the inner tube 12 and a hollow pipe 22 are provided.
, A rebound spring 39 at the time of maximum extension is provided.

In the front fork 10, the piston 32 of the hollow pipe 22 is configured as shown in FIG. The hollow pipe 22 has an upper end portion of a straight pipe 51 as a thin portion 52, and two upper and lower disc-shaped piston pieces 53, 54 are fitted into the thin portion 52 back to back (FIG. 6).
(A), (B)), the tip of the thin portion 52 is crimped to hold the piston pieces 53, 54 (FIG. 6).
(C)). The resin piston ring 5 is inserted into a ring groove 55A formed between the outer circumferences of the piston pieces 53 and 54.
5 is loaded (FIG. 6D). The piston ring 55
It is made of an elastic ring having a cut in a part in the circumferential direction, and forms a perfect circle which is in close contact with the inner periphery of the outer tube 12 in a state where the cut is closed, and is compressed after being loaded into the ring groove 55A. In this state, it is used by being fitted into the inner diameter of the inner tube 12.

In the front fork 10, the suspension spring 24 and the air spring of the gas chamber 37 absorb and reduce the impact received by the wheels, and the vibration of the suspension spring 24 caused by the absorption of the impact is absorbed by the upper oil chamber 33. , By the damping force generated in the lower oil chamber 34.

That is, the front fork 10 performs a damping action as follows. (Compression stroke) During the compression stroke of the front fork 10,
The inner tube 12 is lowered and the pressure in the lower oil chamber 34 is increased, and oil corresponding to the cross-sectional area of the inner tube 12 × the stroke moves from the lower oil chamber 34 to the reservoir chamber 35 through the through hole 36, and this through hole The strain rate of the suspension spring 24 is controlled by obtaining the compression-side damping force due to the passage resistance 36.

At the time of this compression, the oil in the lower oil chamber 34 enters the upper oil chamber 33 by the opening operation of the check valve 43 of the piston part 31 as described above (a), and passes through the orifice 38 of the hollow pipe 22 to the reservoir. The oil in the chamber 35 enters the upper oil chamber 33. As a result, even during compression in which the inner tube 12 descends at a high speed due to unevenness of the road surface, sufficient oil is supplied to the upper oil chamber 33 from the lower oil chamber 34 and the reservoir chamber 35 to prevent a negative pressure from being generated. It is possible to prevent the damping force from no longer being generated in the extension stroke following the compression stroke.

(Telescopic stroke) During the telescopic stroke of the front fork 10, the inner tube 12 rises and the upper oil chamber 33 is raised.
, The oil in the upper oil chamber 33 moves to the reservoir chamber 35 through the orifice 38, and obtains a large extension side damping force due to the passage resistance of the orifice 38, thereby preventing resonance of the suspension spring 24. .

At the time of extension, the inner tube 1
The oil corresponding to the cross-sectional area of 2 × the stroke moves from the reservoir chamber 35 to the lower oil chamber 34 through the through hole 36, and the hydraulic oil corresponding to the rod volume is compensated for in the lower oil chamber 34.

At the time of the extension, the check valve 43 of the piston portion 31 cuts off the communication between the upper oil chamber 33 and the lower oil chamber 34 by the closing operation (b) described above, thereby affecting the generation of the extension side damping force. Has no effect.

However, the front fork 10 has the following configurations (A) to (C). (A) Sliding Structure of Outer Tube 11 and Inner Tube 12 (FIGS. 1 to 3) The inner peripheral surface near the opening end of the outer tube 11 is a first guide portion 61 (length L1) with which the inner tube 12 slides. The inner peripheral surface near the closed end is a second guide portion 62 (length L2) with which the inner tube 12 slides, and the first guide portion 6
The inner peripheral surface between the first and second guide portions 62 is
2 is a large-diameter lightening portion 63 that does not slide.

At this time, the second guide portion 62 is formed continuously from the middle portion of the outer tube 11 to the closed end.

The outer tube 11 can be manufactured by casting a light alloy such as aluminum. The hollow portion 63 is cast (a portion corresponding to a reduced thickness is previously provided to the core, and the core is cast and formed using the core). And the first guide portion 61 and the second guide portion 6
2 can be formed using a BTA tool or the like.

The inner tube 12 is a cold drawn steel tube or a cold extruded steel tube, and the surface of the drawn steel tube or the extruded steel tube is polished and then chrome-plated or the like is applied to the inner tube 12 to form a first guide portion 61 of the outer tube 11. , And a sliding contact surface with the second guide portion 62.

Therefore, according to the front fork 10,
The following operations are provided. The inner tube 12 is supported by the first guide portion 61 and the second guide portion 62 of the outer tube 11 for a long span in the longitudinal direction, and can slide stably.

The outer tube 11 has a first guide portion 61.
Since the lightening portion 63 is formed between the second guide portion 62 and the
The weight of the outer tube 11 and the weight of the front fork 10 can be reduced, and the running performance of the vehicle can be improved.

Outer tube 11 and inner tube 1
The use of the bush eliminates the necessity of using a bush, thereby reducing the number of parts and the associated man-hours and processing man-hours.

(B) Structure of Sealing Device 13 (FIG. 4) As shown in FIG. 4, the outer tube 11 has a first large-diameter hole 71 and a first large hole at the open end where the inner tube 12 is inserted. A second large-diameter hole 72 having an inner diameter larger than that of the first large-diameter hole 71 and a concave groove 73 provided on the inner periphery of the second large-diameter hole 72 are provided on the outer side in the axial direction from the diameter hole 71. Prepare.

As shown in FIG. 4, the sealing device 13 includes a metal reinforcing ring 81 such as a spring material and an inner oil seal lip 82 and an outer oil seal 83 made of a rubber-like elastic material. A peripheral dust seal lip 84, an inner peripheral sub dust seal lip 85, and an outer peripheral dust seal 86 are joined and integrated.

At this time, the reinforcing ring 81 of the sealing device 13
An annular main body portion 81A is bent from the axially outer portion of the main body portion 81A outward in the radial direction with a gap between the main body portion 81A and elastically expanded and contracted in the radial direction to form the second main body portion 81A. An annular elastic portion 81B that can be fitted into the large-diameter hole 72;
An engaging portion 81C that is formed to be bent outward in the radial direction and that can be engaged with the concave groove 73, and an annular support that is formed by bending an inner side portion of the main body portion 81A in the axial direction toward an inner peripheral side of the main body portion 81A. Part 81
D. The support portion 81D is formed by bending the axially inner end of the main body portion 81A so as to be in contact with the inner periphery of the main body portion 81A, and bending the distal end of the bent radially inward.

The inner peripheral oil seal lip 82
Is provided on the support portion 81 </ b> D of the reinforcing ring 81, is provided with a diameter reducing behavior by a spring 87, and comes into sliding contact with the outer periphery of the inner tube 12 in a liquid-tight manner. The outer peripheral oil seal portion 83 is
The reinforcing ring 81 is provided on the outer peripheral portion on the inner side in the axial direction of the main body portion 81A, and is fitted in the first large-diameter hole 71 in a liquid-tight manner.

The inner peripheral side dust seal lip 84
Is provided on the inner peripheral portion of the main body portion 81 </ b> A of the reinforcing ring 81 in the axial direction, and is in sliding contact with the outer periphery of the inner tube 12. The inner peripheral side sub dust seal lip portion 85 is provided outside the inner peripheral side oil seal lip portion 82 (and inside the inner peripheral side dust seal lip portion 84) in the support portion 81 </ b> D of the reinforcing ring 81. In sliding contact with The outer peripheral side dust seal portion 86 is provided on the outer peripheral portion of the elastic portion 81 </ b> B of the reinforcing ring 81, and fits in the second large-diameter hole 72.

The inner peripheral oil seal lip 82 and the inner peripheral sub dust seal lip 85 are integrated, and the inner peripheral dust seal lip 84 and the outer peripheral dust seal 8 are integrated.
6 may be integrated.

Therefore, according to the front fork 10,
The following operations are provided. Inner peripheral oil seal lip 82, outer peripheral oil seal 83, inner peripheral dust seal lip 84, inner peripheral sub dust seal lip 85, and outer peripheral dust seal 8
When the sealing device 13 provided with the outer tube 6 is attached to the open end of the outer tube 11, the engaging portion 81C of the elastic portion 81B is placed in the second large-diameter hole 72 of the outer tube 11, and the elastic portion 8
After the engagement portion 81C is slid into the second large-diameter hole 72 and engaged with the concave groove 73 in a state where the diameter of the elastic portion 1B is reduced, the elastic portion 81
By resiliently restoring B and expanding the diameter, the sealing device 13 can be prevented from coming off from the opening end without using a fixing member such as a stopper ring, and can be firmly fixed.

The sealing device 13 includes the inner peripheral oil seal lip 82, the outer peripheral oil seal 83, the inner peripheral dust seal lip 84, the inner peripheral sub dust seal lip 85, and the outer peripheral dust seal 86. An oil seal mechanism in which the inner peripheral side oil seal lip portion 82 is in sliding contact with the inner tube 12 in a liquid-tight manner, and the outer peripheral side oil seal portion 83 is fitted in the first large-diameter hole 71 of the outer tube 11 in a liquid-tight manner; The inner peripheral side dust seal lip 84 and the inner peripheral side sub dust seal lip 85
, And the dust seal mechanism in which the outer peripheral side dust seal portion 86 slides in contact with the second large-diameter hole 72 of the outer tube 11 does not become a separate body, thereby reducing the number of parts and the number of assembling steps, and reducing the product cost. it can.

The sealing device 13 includes a main body 8 of the reinforcing ring 81.
The supporting portion 81D can be easily formed by bending the inner end in the axial direction of 1A.

(C) Fixing Structure of Hollow Pipe 22 with Bolt 21 (FIG. 5) A mounting hole 91 is provided at the bottom of the outer tube 11, and a small-diameter portion 92 is provided at the base end of the hollow pipe 22.
The small-diameter portion 92 is inserted into the mounting hole 91 of the outer tube 11, and a sealing agent made of resin or the like is applied around a threaded end of the bolt 21 which is engaged with the bottom of the outer tube 11 from outside. The threaded end of the bolt 21 is screwed into the threaded portion 92 </ b> A having the inner diameter of the small diameter portion 92 of the hollow pipe 22.
As a result, the outer peripheral surface 93 on the base end side of the hollow pipe 22 is formed.
Against the inner peripheral surface 94 on the bottom side of the outer tube 11 to draw and fix the hollow pipe 22.

At this time, the outer tube 11 is made of a light alloy of aluminum (for example, AC2BF of Table 1) as described above, and the hollow pipe 22 is made of a steel pipe or the like (for example, STKM of Table 1).
11A), the outer tube 11
Is made of a material which is softer than the hollow pipe 22 as shown in Table 1, for example.
3 and the inner peripheral surface 94 of the outer tube 11 are tapered surfaces that are wedge-coupled (taper-coupled) to each other.

[0051]

[Table 1]

Accordingly, the front fork 10 has the following operation. At the mounting portion of the hollow pipe 22 in the outer tube 11, the tapered outer peripheral surface 93 of the hollow pipe 22 is taperedly fitted to the tapered outer peripheral surface 94 of the outer tube 11 by the fastening force of the bolt 21 and is strongly wedge-coupled.

The tapered inner peripheral surface 9 of the outer tube 11
Numeral 4 is softer than the tapered outer peripheral surface 93 of the hollow pipe 22, and both are well fitted and adhered to each other under the above-mentioned strong wedge connection. Even with a simple structure that does not require the use of packings, a certain sealing action is obtained. And the oil chamber 34 inside the outer tube 11 can be reliably sealed. The reservoir chamber 35 inside the hollow pipe 22 is sealed by a sealing material around the threaded end of the bolt 21.

In the front fork 10, a copper packing or the like is inserted under the neck of the bolt 21 in the above-mentioned mounting portion of the hollow pipe 22 in the outer tube 11, and the head of the bolt 21 and the outer tube 11 are connected to each other. Mounting hole 9
By sandwiching the copper packing or the like between the outer peripheral surface of the outer tube 1 and the outer peripheral surface of the outer tube 11, the oil chamber 34 inside the outer tube 11 can be more reliably sealed.

The first modification of FIG. 8 is different from the embodiment of FIG. 4 in that a supporting portion 81 of a reinforcing ring 81 constituting the sealing device 13 is provided.
D is formed by bending the axially inner middle portion of the main body portion 81A inward in the radial direction. According to this, the sealing device 13 can easily form the support portion 81D by bending the axially intermediate portion of the main body portion 81A.

The difference between the second modification of FIG. 9 and the embodiment of FIG. 4 is as follows. That is, the outer tube 11
A large-diameter hole 101 and a concave groove 102 provided on the inner periphery of the large-diameter hole 101 are formed at the open end into which the inner tube 12 is inserted.
Is provided. The sealing device 110 includes a metal reinforcing ring 111 such as a spring material, and an inner peripheral oil seal lip 112, an outer peripheral oil seal 113, an inner peripheral dust seal lip 114, and an inner peripheral The side sub dust seal lip 115 and the outer peripheral side dust seal 116 are joined and integrated.

At this time, the reinforcing ring 111 of the sealing device 110
Is an annular main body 111A that can be fitted into the large-diameter hole 101.
And an engaging portion 111B which is radially outwardly cut out from the main body portion 111A and elastically expands and contracts in the radial direction to be able to engage with the concave groove 102; and an axially inner portion of the main body portion 111A An annular support portion 111 bent on the inner peripheral side of 111A
C. The support portion 111C is formed by bending the axially inner end of the main body 111A so as to be in contact with the inner periphery of the main body 111A, and bending the distal end of the bend radially inward.

Then, the inner peripheral side oil seal lip 11
Numeral 2 is provided on the support portion 111 </ b> D of the reinforcing ring 111, and is provided with the property of reducing the diameter by the spring 117, and comes into liquid-tight sliding contact with the outer periphery of the inner tube 12. The outer peripheral side oil seal portion 113 is provided on the outer peripheral portion of the main body 111 </ b> A of the reinforcing ring 111 in the axial direction, and is fitted in the large-diameter hole 101 in a liquid-tight manner.

The inner peripheral side dust seal lip 114
Is provided on the inner peripheral portion of the main body 111 </ b> A of the reinforcing ring 111 on the outside in the axial direction, and slides on the outer periphery of the inner tube 12.
The inner peripheral side sub dust seal lip 115 is
1 outside the inner peripheral oil seal lip 112 (and the inner peripheral dust seal lip 1
14 (inside of the inner tube 14), and is in sliding contact with the outer periphery of the inner tube 12. The outer peripheral side dust seal portion 116 is
1 is provided on the outer periphery of the main body 111A, and the large-diameter hole 101 is provided.
Fits.

The inner peripheral oil seal lip 112 and the inner peripheral sub dust seal lip 115 are integrated,
The inner peripheral side dust seal lip portion 114 and the outer peripheral side dust seal portion 116 may be integrated.

Therefore, according to the second modification, the following operation is provided. The sealing device 110 including the inner peripheral side oil seal lip portion 112, the outer peripheral side oil seal portion 113, the inner peripheral side dust seal lip portion 114, the inner peripheral side sub dust seal lip portion 115, and the outer peripheral side dust seal portion 116 At the time of attachment to the open end, the engaging portion 111B of the main body 111A is placed in the large-diameter hole 101 of the outer tube 11 and the diameter of the engaging portion 111B is reduced.
1 to engage with the concave groove 102,
By resiliently restoring B and expanding the diameter, the sealing device 110 can be prevented from coming off from the opening end without using a fixing member such as a stopper ring, and can be firmly fixed.

The sealing device 110 includes the inner peripheral oil seal lip 112, the outer peripheral oil seal 113, the inner peripheral dust seal lip 114, the inner peripheral sub dust seal lip 115, and the outer peripheral dust seal 116. The inner peripheral side oil seal lip portion 112 is in sliding contact with the inner tube 12 in a liquid-tight manner, and the outer peripheral side oil seal portion 1
An oil seal mechanism 13 is fitted in the large-diameter hole 101 of the outer tube 11 in a liquid-tight manner, and an inner-peripheral-side dust seal lip 114 and an inner-peripheral sub-dust seal lip 115 slidably contact the inner tube 12. 11
The dust seal mechanism 6 that slides on the large-diameter hole 101 of the outer tube 11 does not become a separate body, so that the number of parts and the number of assembling steps can be reduced, and the product cost can be reduced.

In the sealing device 110, the support portion 111C can be easily formed by bending the inner end in the axial direction of the main body portion 111A of the reinforcing ring 111.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration of the present invention is not limited to the embodiments, and the design can be changed within a range not departing from the gist of the present invention. The present invention is also included in the present invention.

[0065]

As described above, according to the present invention, when providing the oil seal mechanism and the dust seal mechanism at the opening end of the outer tube, the number of parts and the number of assembling steps can be reduced, and the product cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall sectional view showing a front fork.

FIG. 2 is an enlarged sectional view of a lower portion of a front fork.

FIG. 3 is an enlarged cross-sectional view of an upper portion of a front fork.

FIG. 4 is an enlarged sectional view showing a sealing device provided at an open end of an outer tube.

FIG. 5 is an enlarged sectional view showing a mounting portion of the hollow pipe.

FIG. 6 is a schematic view showing a procedure for manufacturing a piston portion of a hollow pipe.

FIG. 7 is a schematic view showing an operation of a check valve of a piston portion of the inner tube.

FIG. 8 is a sectional view showing a first modification of the present invention.

FIG. 9 is a sectional view showing a second modification of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Front fork (vehicle shock absorber) 11 Outer tube 12 Inner tube 13, 110 Sealing device 71 First large-diameter hole 72 Second large-diameter hole 73, 102 Concave groove 81A, 111A Main body portion 81B Elastic portion 81C, 111B Engagement part 81D, 111C Support part 82, 112 Inner peripheral side oil seal lip part 83, 113 Outer peripheral side oil seal part 84, 114 Inner peripheral side dust seal lip part 86, 115 Outer peripheral side dust seal part 101 Large diameter hole

Claims (6)

[Claims] An inner tube is slidably inserted into an outer tube, and hydraulic oil is sealed inside the outer tube and the inner tube. A first end of the outer tube is inserted into an opening end of the inner tube into which the inner tube is inserted. A large-diameter hole, and a second large-diameter hole having an inner diameter larger than the first large-diameter hole provided outside of the first large-diameter hole in the axial direction;
A sealing device for a shock absorber for a vehicle, comprising a concave groove provided on an inner periphery of a second large-diameter hole, the sealing device being mounted on the open end of an outer tube, wherein an annular main body portion and an axial direction of the main body portion are provided. An annular elastic portion that is bent outward from the outer portion in the radial direction with a gap between the main body portion and the elastic portion and is elastically expandable and contractible in the radial direction and can be fitted into the second large-diameter hole; An engaging portion formed radially outward from the elastic portion and capable of engaging with the concave groove; and an annular support portion formed by bending an axially inner portion of the main body portion on the inner peripheral side of the main body portion. An inner oil seal lip portion provided on the support portion and slidably contacting the outer circumference of the inner tube; and an outer oil portion fitted on the first large-diameter hole provided on the outer peripheral portion on the inner side in the axial direction of the main body portion. A seal portion, and an inner peripheral side dust seal lip portion provided on an axially outer inner peripheral portion of the main body portion and slidably contacting the outer periphery of the inner tube. Sealing device for a vehicle shock absorber comprising a. 2. The sealing device for a shock absorber for a vehicle according to claim 1, further comprising an outer peripheral side dust seal portion provided on an outer peripheral portion of the elastic portion and fitted to the second large-diameter hole. 3. An inner tube is slidably inserted into an outer tube, and hydraulic oil is sealed inside the outer tube and the inner tube. A large diameter is provided at an open end of the outer tube into which the inner tube is inserted. A sealing device for a shock absorber for a vehicle, comprising a hole and a concave groove provided on an inner periphery of the large-diameter hole, the annular body being fitted to the large-diameter hole. And a notch formed radially outward from the main body, and capable of elastically expanding and contracting in the radial direction and engaging with the concave groove; and an inner peripheral portion of the main body in the axial direction. An annular support portion bent on the side, an inner peripheral oil seal lip portion provided on the support portion for sliding contact with the outer periphery of the inner tube, and a large-diameter hole provided on an outer peripheral portion on the inner side in the axial direction of the main body portion. Outer side oil seal part that fits with the inside of the body part on the outside in the axial direction Provided, the vehicle shock absorber of a sealing device comprising a and an inner peripheral side dust seal lip portion in sliding contact with the outer periphery of the inner tube. 4. The sealing device for a shock absorber for a vehicle according to claim 3, further comprising an outer peripheral side dust seal portion provided in an outer peripheral portion of the main body portion on the outer side in the axial direction and fitted to a large-diameter hole. 5. The support portion is formed by bending an axially inner end of a main body portion so as to be in contact with an inner periphery of the main body portion, and bending a tip end of the bend radially inward. Claim 1
The sealing device for a shock absorber for a vehicle according to any one of Claims 4. 6. The sealing device for a shock absorber for a vehicle according to claim 1, wherein the support portion is formed by bending an intermediate portion in the axial direction of the main body portion inward in the radial direction.