JP2023004256A - Fixing structure of seal member, fixing method of seal member and shock absorber - Google Patents

Abstract

To provide a fixing structure of a seal member which can secure favorable seal performance without causing the lowering of the rigidity of a caulking part, a fixing method of the seal member and a shock absorber.SOLUTION: A fixing structure of a seal member 1 of this invention having an annular insert metal 11, and seal parts 12, 13 integrally arranged at the insert metal 11, and fixing the seal member 1 for tightly sealing the inside of a tube 2 by making an external periphery of the insert metal 11 fit to an internal periphery of the tube 2, by caulking a tube end of the tube 2 to an internal peripheral side comprises: a step part 11b formed of an annular recess which is formed up to the outermost periphery at an external peripheral side of an outside end 11a at which the insert metal 11 is oriented outward with respect to the tube; and a chamfered part 11c arranged at an external periphery of the step part 11b at the outside end 11a. A length L1 of the chamfered part 11c in the axial direction is set longer than a length L2 of the step part 11b in the axial direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a sealing member fixing structure, a sealing member fixing method, and a shock absorber.

A conventional shock absorber comprises, for example, a cylinder, a piston that is slidably inserted into the cylinder and partitions the inside of the cylinder into two working chambers, and a rod that is connected at one end to the piston. , when it expands and contracts, resistance is given to the flow of hydraulic oil that flows between the working chambers, creating a differential pressure between the working chambers, generating a damping force, and suppressing the vibration of the object to be damped ( For example, see Patent Document 1).

In addition, this shock absorber is provided with a seal member which is in sliding contact with the outer periphery of the rod, and this seal member prevents hydraulic oil in the cylinder from leaking from around the rod to keep the inside of the cylinder oil-tight. I keep

Specifically, the sealing member includes an annular insert metal, a rubber inner peripheral seal integrated with the inner peripheral side of the insert metal, and a rubber outer peripheral seal integrated with the outer peripheral side of the insert metal. It has Taking a double-cylinder shock absorber as an example, the seal member is stacked on a rod guide that supports a rod and is inserted into the inner circumference of an outer tube that accommodates a cylinder. It is fixed to the outer tube by crimping it to the circumferential side.

The sealing member fixed in this manner brings the inner peripheral seal into sliding contact with the outer periphery of the rod and the outer peripheral seal in close contact with the inner periphery of the outer tube to seal the inside of the outer tube and prevent oil from entering the cylinder and the outer tube. Prevents leaks.

The seal member is formed by insert molding, in which an insert metal is inserted into a mold that forms an inner peripheral seal and an outer peripheral seal, and then a rubber material is filled into the mold to integrate the inner peripheral seal and the outer peripheral seal with the insert metal. can get. It is necessary to apply adhesive to the insert metal before insert molding, but it is troublesome to apply adhesive only to the installation areas of the inner and outer seals, so the entire insert metal is immersed in liquid adhesive. The adhesive is applied to the entire insert metal because the adhesive is applied to the insert metal. Then, in the sealing member obtained after insert molding, a thin rubber film is formed on the insert metal other than the portions where the inner peripheral seal and the outer peripheral seal are installed.

After the seal member thus obtained is fitted to the inner circumference of the outer tube, an axial force is applied, and then the entire circumference of the tube end of the outer tube is crimped to the inner circumference by roll crimping. It is fixed to the outer tube by laying it down and bringing it into close contact with the outer peripheral side of the outer surface facing the outside of the insert metal.

When the sealing member is fixed by such crimping of the outer tube, the rubber film adhered to the outer end of the insert metal is removed from the tube end in the process in which the tube end of the outer tube is folded toward the inner peripheral side. When approaching, a string-like rubber piece is pushed out to the inner peripheral side, and the rubber piece may be torn off and enter between the inner peripheral seal portion and the rod. In such a state, the sealing performance around the outer periphery of the rod deteriorates, so a stepped portion is provided by forming an annular recess on the outer periphery of the outer end of the insert metal.

When the stepped portion is provided in this way, after the tube end of the outer tube is crimped, a space is created between the tube end and the stepped portion on the inner peripheral side to accommodate the rubber piece. Movement to the peripheral side can be suppressed, and good sealing performance of the sealing member can be ensured.

JP-A-2002-070920

When the seal member is fixed by crimping the tube end of the outer tube in this way, the outer tube is bent at a right angle starting from the edge of the outer periphery of the outer end of the insert metal and rides on the corner on the inner peripheral side of the stepped portion. . Therefore, as shown in FIG. 4, the inner periphery of the crimped portion 100a formed by crimping the tube end of the outer tube 100 cannot be in close contact with the insert metal 101 near the outer periphery of the outer end of the insert metal 101. , and a gap A is formed.

When the caulked portion 100a of the outer tube 100 is thus peeled off from the outer peripheral portion of the outer end of the insert metal 101, the strength of the caulked portion 100a of the outer tube 100 is reduced, and the sealing performance at the outer periphery of the sealing member deteriorates. there is a possibility.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a sealing member fixing structure, a sealing member fixing method, and a shock absorber that can ensure good sealing performance without reducing the strength of a crimped portion.

In order to solve the above-described problems, the seal member fixing structure of the present invention has an annular insert metal and a seal portion provided integrally with the insert metal, and the outer periphery of the insert metal is fitted to the inner periphery of the tube. A sealing member fixing structure in which a sealing member that seals the inside of a tube is fixed by crimping the tube end of the tube toward the inner peripheral side, wherein the insert metal is attached to the outer periphery of the outer end facing outward with respect to the tube and a chamfered portion provided on the outer periphery of the stepped portion at the outer end, the axial length of the chamfered portion being equal to the axis of the stepped portion It is characterized by being longer than the directional length.

According to the sealing member fixing structure configured in this way, since the axial length of the chamfered portion is longer than the axial length of the stepped portion, the tube end of the tube is crimped to form the crimped portion. When processed, the caulked portion deforms following the chamfered portion on the outer edge of the insert metal without being affected by the stepped portion. The circumference adheres to the insert metal without peeling.

Further, in the sealing member fixing structure, the tube may be made of an aluminum alloy. According to the fixing structure of the sealing member configured in this way, it is possible to reduce the weight of the shock absorber or the like to which the fixing structure of the sealing member is applied while ensuring the strength even if the tube is made of an aluminum alloy which is softer than steel. .

Furthermore, in order to solve the above-described problems, a method of fixing a seal member according to the present invention provides a ring-shaped insert metal and a sealing portion integrally provided with the insert metal, and a seal member provided on the inner circumference of the tube and the outer circumference of the insert metal. A method of fixing a seal member that seals the inside of the tube by fitting the A seal member provided with a stepped portion formed to the outermost periphery on the outer peripheral side and a chamfered portion having an axial length longer than the axial length of the stepped portion on the outer periphery of the stepped portion is inserted into the tube, and In this method, the seal member is fixed to the tube by crimping the tube end toward the inner peripheral side.

According to the sealing member fixing method configured in this way, since the axial length of the chamfered portion is longer than the axial length of the stepped portion, the tube end of the tube is crimped to form the crimped portion. When processed, the caulked portion deforms following the chamfered portion on the outer edge of the insert metal without being affected by the stepped portion. The circumference adheres to the insert metal without peeling.

Further, in order to solve the above-described problems, the shock absorber of the present invention includes a rod inserted into a tube so as to be movable in the axial direction, and an annular shock absorber fitted to the inner circumference of the tube and the outer circumference of the rod. A rod guide that guides the movement of the rod by slidably contacting the tube, an annular insert metal fitted to the inner circumference of the tube, and an inner circumference seal that is integrally provided on the inner circumference side of the insert metal and is in sliding contact with the outer circumference of the rod. and an outer peripheral seal portion that is integrally provided on the outer peripheral side of the insert metal and contacts the inner periphery of the tube, and the insert metal is brought into contact with the outer end of the rod guide facing outward with respect to the tube. A stepped portion provided by an annular recess formed up to the outermost periphery on the outer peripheral side of the outer end where the insert metal faces outward with respect to the tube and a stepped portion at the outer end The axial length of the chamfered portion is longer than the axial length of the stepped portion, and the seal member crimps the tube end of the tube to the inner peripheral side to secure the tube. It is characterized in that it is fixed to

According to the shock absorber configured in this way, since the axial length of the chamfered portion is longer than the axial length of the stepped portion, the tube end of the tube is crimped to form the crimped portion. Then, the caulked portion deforms following the chamfered portion on the outer periphery of the outer edge of the insert metal without being affected by the stepped portion, and the inner circumference at the starting point of the bending of the caulked portion peels off at the outer periphery of the insert metal. It adheres to the insert metal without

According to the sealing member fixing structure, the sealing member fixing method, and the shock absorber of the present invention, it is possible to ensure good sealing performance without causing a reduction in the strength of the crimped portion.

1 is a vertical cross-sectional view of a shock absorber to which a sealing member fixing structure according to one embodiment is applied; FIG. 1 is a partially enlarged vertical cross-sectional view of a shock absorber to which a sealing member fixing structure according to one embodiment is applied; FIG. It is a figure explaining the fixing method of the sealing member in one embodiment. and FIG. 11 is an enlarged vertical cross-sectional view of a conventional seal member fixing structure.

The present invention will be described below with reference to the drawings. As shown in FIG. 1, the fixing structure of the seal member 1 in one embodiment is applied to the shock absorber D, and is in sliding contact with the outer periphery of the rod 3 entering and exiting the cylinder 2 as a tube in the shock absorber D. It abuts on the inner periphery of the cylinder 2 to seal the inside of the cylinder 2 .

Each part will be described in detail below. First, the structure of the buffer D will be explained. The damper D is configured in this case as a monotube damper, comprising a cylinder 2 as a tube, a rod 3 inserted axially movably in the cylinder 2, and an annular shape, the cylinder 2 and a rod guide 4 fitted to the inner circumference of the cylinder 2 and slidingly contacting the outer circumference of the rod 3 to guide the movement of the rod 3; An annular sealing member 1 is provided.

In addition to the above configuration, the shock absorber D is slidably inserted into the cylinder 2 and divides the cylinder 2 into an air chamber G filled with gas and a liquid chamber L filled with liquid. A free piston 5, a piston 6 which is slidably inserted into the cylinder 2 and which divides the liquid chamber L in the cylinder 2 into an expansion side chamber R1 and a compression side chamber R2, and an expansion side chamber R1 provided in the piston 6. It comprises a passage 7 that communicates with the pressure side chamber R2 and a damping valve 8 that gives resistance to the flow of liquid passing through the passage 7.

In the shock absorber D of the present embodiment, the cylinder 2 is a cylinder made of aluminum alloy, and has a bottomed cylinder shape with the lower end closed in FIG. It fixes the seal member 1 and the rod guide 4 which are accommodated in the cylinder 2 . If the cylinder 2 is a cylinder whose bottom is also open, the opening of the bottom of the cylinder 2 may be closed with a cap.

The rod guide 4 has an annular shape, and has a concave portion 4b provided on the inner peripheral side of an outer end 4a facing outward, which is opposite to the cylinder 2, which is the upper end in FIG. 1, and the upper end in FIG. It comprises an annular recess 4c provided along the entire outer periphery of the outer end 4a and a tubular bush 4d provided on the inner periphery and in sliding contact with the outer periphery of the rod 3. As shown in FIG. Further, the rod guide 4 is fitted to the inner periphery of the cylinder 2 at the upper end in FIG. 1 in a state in which downward movement in FIG. 2 is closed. Further, the rod 3 is inserted in the inner periphery of the rod guide 4, and the rod guide 4 slides the bush 4d on the cylindrical side of the inner periphery against the outer periphery of the rod 3 to move the rod 3 vertically in FIG. guides axial movement.

1 and 2, the sealing member 1 arranged above the rod guide 4 in FIG. An annular inner peripheral seal 12 and an annular outer peripheral seal portion 13 integrally provided on the outer peripheral side of the insert metal 11 are provided. The seal member 1 is fitted to the inner circumference of the cylinder 2 while coming into contact with the outer end 4a of the rod guide 4 opposite to the cylinder side, and the rod 3 is inserted through the inner circumference to form an inner circumference seal 12. The outer circumference of the rod 3 is slidably contacted and the outer circumference seal 13 is brought into contact with the inner circumference of the cylinder 2 to seal the inside of the cylinder 2 .

The insert metal 11 is an annular plate having a substantially rectangular cross section, and extends along the outermost periphery of the outer end 11a, which is the end face (upper end face in FIG. 1) facing outward with respect to the cylinder 2. and a chamfered portion 11c formed on the outer periphery of the stepped portion 11a, which is the outermost periphery of the outer end 11a. The insert metal 11 is fitted to the inner circumference of the cylinder 2 with the outer end 11a on the side opposite to the cylinder facing toward the atmosphere.

The stepped portion 11b is formed by providing an annular recess from the middle of the outer periphery of the outer end 11a of the insert metal 11 to the outermost periphery. be. In the present embodiment, the chamfered portion 11c is formed by chamfering the outermost periphery of the outer end of the insert metal 11, but may be formed by performing a round chamfering. 1 of the chamfered portion 11c is set to be longer than the axial length L2 of the stepped portion 11b in FIG. there is That is, as shown in FIG. 2, when the axial length of the chamfered portion 11c is L1 and the axial length of the stepped portion 11b is L2, the chamfered portion 11c and the stepped portion 11b are arranged so as to satisfy L1>L2. dimensions are set.

The inner peripheral seal portion 12 has an annular shape, and is integrated with the insert metal 11 by insert-molding a rubber material around the entire inner periphery of the insert metal 11. A first lip 12a is provided on the side opposite to the cylinder of the first lip 12a to prevent liquid from leaking out of the cylinder 2. and a second lip 12b to prevent. When the seal member 1 is stacked on the outer end 4 a of the rod guide 4 and inserted into the cylinder 2 , the inner peripheral seal 12 is such that the first lip 12 a is positioned inside the recess 4 b provided on the inner periphery of the rod guide 4 . are housed in In addition, when the seal member 1 is inserted into the cylinder 2 , the inner peripheral seal 12 brings both the first lip 12 a and the second lip 12 b into sliding contact with the outer periphery of the rod 3 to seal the periphery of the rod 3 .

When the seal member 1 is stacked on the outer end 4a of the rod guide 4 and inserted into the cylinder 2, the outer peripheral seal 13 is formed in the annular gap between the cylinder 2 and the recessed portion 4c provided on the outer periphery of the rod guide 4. It penetrates into both the rod guide 4 and the cylinder 2 and seals between the cylinder 2 and the rod guide 4. - 特許庁

The seal member 1 constructed in this manner is inserted into the cylinder 2 together with the rod guide 4, and is formed by rolling the upper end of the cylinder 2 in FIG. 1 and bending it inward. It is fixed to the cylinder 2 by being clamped together with the rod guide 4 by the caulking portion 2a and the snap ring 9. As shown in FIG.

The free piston 5 is slidably inserted into the cylinder 2 and divides the inside of the cylinder 2 into an air chamber G and a liquid chamber L. One of G and liquid chamber L is enlarged and the other is contracted. Further, the piston 6 is slidably inserted into the cylinder 2 and connected to the tip of the rod 3, and divides the liquid chamber L in the cylinder 2 into the expansion side chamber R1 and the compression side chamber R2.

The piston 6 is provided with a passage 7 that communicates the expansion side chamber R1 and the compression side chamber R2, and a damping valve 8 that gives resistance to the flow of liquid passing through the passage 7. In this embodiment, the damping valve 8 is a valve that allows the liquid to flow in both directions from the expansion side chamber R1 to the compression side chamber R2 and from the compression side chamber R2 to the expansion side chamber R1. However, when a plurality of passages are installed in the piston 6, a one-way valve that allows only the flow of liquid from the expansion side chamber R1 to the compression side chamber R2 is provided in a part of the passage, and the flow from the compression side chamber R2 to the expansion side chamber R1 The remaining passages may be provided with one-way valves that allow only the flow of liquid to and from. The liquid filled in the cylinder 2 may be water, an aqueous solution, an electrorheological fluid, a magnetorheological fluid, or any other fluid that is applicable to the shock absorber. In the case of a viscous fluid or a magneto-rheological fluid, instead of the damping valve 8, damping force generating means for applying an electric field or a magnetic field to the passage 7 may be provided. The gas filled in the air chamber G may be air, but is preferably an inert gas such as nitrogen.

As described above, the shock absorber D is a single-tube shock absorber, and when it expands, it is compressed through the passage 7 provided in the piston 6. FIG. The damping valve 8 gives resistance to the flow of the liquid moving to the compression side chamber R2 on the lower side of the 1 to generate a damping force on the expansion side. On the contrary, when the shock absorber D is contracted, the liquid moving from the compression side chamber R2 in the lower part of FIG. The flow is resisted by the damping valve 8 to generate a damping force on the compression side.

Further, in the shock absorber D, the expansion or contraction of the air chamber G compensates for the volume of the rod 3 entering or exiting the cylinder 2 during the expansion or contraction stroke.

The shock absorber D described above is an example, and an outer tube is provided on the outer circumference of the cylinder 2 to compensate for the volume of the rod 3 entering and exiting the cylinder 2 in the annular gap between the cylinder 2 and the outer tube. A dual-cylinder shock absorber provided with a reservoir may be used, or a double-rod shock absorber may be used in which the rod 3 passes through the piston 6 and protrudes from both ends of the cylinder 2 to the outside. In this way, when the shock absorber D is a double-tube shock absorber, the outer tube is used as a tube and the sealing member 1 is fixed by crimping the tube end of the outer tube. should be sealed.

In order to assemble the shock absorber D configured as described above, the following is performed. First, as described above, the insert metal 11 of the seal member 1 is provided with a stepped portion 11b and a chamfered portion 11c at the outer end 11a opposite to the cylinder. Specifically, after forming the stepped portion 11b by cutting the outer peripheral portion of the outer end 11a of the insert metal 11, the outermost periphery of the outer end 11a of the insert metal 11 is chamfered by cutting to form a chamfered portion 11c. to form The order of forming the stepped portion 11b and the chamfered portion 11c in the insert metal 11 may be reversed. When the insert metal 11 is formed by stamping from a plate material, the stepped portion 11b and the chamfered portion 11c may be punched out with a die and formed at the same time. When the insert metal 11 is molded by sintering or the like, a mold capable of forming the stepped portion 11b and the chamfered portion 11c is used to mold the stepped portion 11b and the chamfered portion 11c simultaneously with sintering. may

After the insert metal 11 is obtained, an adhesive is applied to the insert metal 11, and then the insert metal 11 is inserted into a mold (not shown) that forms the inner peripheral seal portion 12 and the outer peripheral seal portion 13. Inject the rubber material and bake it. Then, the inner peripheral seal portion 12 and the outer peripheral seal portion 13 made of a rubber material are integrated with the insert metal 11 by insert molding to obtain the sealing member 1 .

After inserting the free piston 5 into the cylinder 2 and inserting the piston 6 assembled with the rod 3 into the cylinder 2 , the snap ring 9 is attached to the cylinder 2 .

Subsequently, the seal member 1 obtained as described above is attached to the cylinder 2 by moving the rod guide 4 until the rod guide 4 comes into contact with the snap ring 9 previously attached to the inner periphery of the cylinder 2, as shown in FIG. It is inserted into the cylinder 2 after being inserted into the inside.

Specifically, the sealing member 1 is formed by fitting the outer periphery of the insert metal 11 to the inner periphery of the cylinder 2 and bringing the inner side surface 11d of the insert metal 11 facing the cylinder side and the outer end 4a of the rod guide 4 into contact. and is inserted into the cylinder 2. The insertion of the sealing member 1 into the cylinder 2 may be performed together with the rod guide 4 while being superimposed on the rod guide 4 .

When the seal member 1 is inserted into the cylinder 2 together with the rod guide 4, the seal member 1 is inserted from the upper end of the cylinder 2 by a predetermined length, and the pipe end portion of the cylinder 2 is pushed further than the outer end 11a of the insert metal 11. Axial protrude.

With the sealing member 1 inserted into the cylinder 2, the entire circumference or several portions of the tube end of the cylinder 2 are slightly bent inward and temporarily caulked.

Then, the seal member 1 is temporarily fixed to the cylinder 2 by the tube end bent toward the inner peripheral side of the cylinder 2 by temporary crimping. After that, while applying an axial force to the seal member 1 toward the rod guide 4 side, the entire circumference of the pipe end of the cylinder 2 is crimped from the outer peripheral side, thereby forming a shape shown by a broken line in FIG. , the tube end is bent toward the inside of the cylinder 2 to form a caulked portion 2a, and the sealing member 1 and the rod guide 4 are sandwiched between the caulked portion 2a and the snap ring 9 to be fixed to the cylinder 2. be done.

Here, as shown in FIG. 2, the caulking portion 2a of the cylinder 2 is bent and deformed starting from the chamfered portion 11c on the outer periphery of the outer end 11a of the insert metal 11. As shown in FIG. The tip of the caulking portion 2a rides on the corner portion 11e of the inner peripheral wall of the stepped portion 11b formed on the inner peripheral side of the chamfered portion 11c of the outer peripheral surface 11a of the insert metal 11 to reach the inner peripheral side. . In this way, the crimped portion 2a formed by crimping the pipe end of the cylinder 2 rides on the corner portion 11e of the inner periphery of the stepped portion 11b, but the chamfered portion 11c is more than the axial length L2 of the stepped portion 11b. Since the axial length L1 of is longer than the stepped portion 11b, the insert metal 11 deforms following the chamfered portion 11c on the outer periphery of the outer end 11a of the insert metal 11 without being affected by the stepped portion 11b. is in close contact with the upper surface in FIG.

It should be noted that when the tube end of the cylinder 2 is crimped and the tube end is gradually folded inward, the rubber film formed on the upper surface of the stepped portion 11b of the insert metal 11 is removed from the inner periphery. Thread-like rubber pieces are generated by being pushed out to the side. However, a gap S for containing the rubber piece is formed at the corner between the crimped portion 2a after the crimping process and the wall surface of the inner periphery of the stepped portion 11b, and the rubber piece is trapped inside the insert metal 11. Since the movement to the peripheral side is restricted, the sealing performance of the seal member 1 is not impaired.

As described above, the fixing structure of the seal member 1 of the present embodiment includes the annular insert metal 11 and the inner peripheral seal portion (seal portion) 12 and the outer peripheral seal portion (seal portion) provided integrally with the insert metal 11. 13, the seal member 1 for sealing the inside of the cylinder (tube) 2 by fitting the outer periphery of the insert metal 11 to the inner periphery of the cylinder (tube) 2 is placed on the inner periphery side of the cylinder (tube) 2. A fixing structure for a seal member 1 that is crimped and fixed to a cylinder (tube) 2, and an insert metal 11 is provided by an annular recess formed to the outermost periphery on the outer peripheral side of an outer end 11a facing outward with respect to a cylinder (tube) 2. It has a stepped portion 11b and a chamfered portion 11c provided on the outer periphery of the stepped portion 11b at the outer end 11a, and the axial length L1 of the chamfered portion 11c is longer than the axial length L2 of the stepped portion 11b. ing.

According to the fixing structure of the seal member 1 configured in this way, since the axial length L1 of the chamfered portion 11c is longer than the axial length L2 of the stepped portion 11b, the pipe end of the cylinder (tube) 2 is is crimped to form the crimped portion 2a, the crimped portion 2a is deformed following the chamfered portion 11c on the outer periphery of the outer end 11a of the insert metal 11 without being affected by the stepped portion 11b. At the outer periphery of the insert metal 11, the inner periphery at the starting point of the bending of the caulked portion 2a adheres to the insert metal 11 without peeling off. Therefore, according to the fixing structure of the seal member 1 of the present embodiment, the caulked portion 2a of the cylinder (tube) 2 is in close contact with the insert metal 11 without peeling off, so that the strength of the caulked portion 2a is reduced. Therefore, good sealing performance of the sealing member 1 can be ensured.

In addition, in the fixing structure of the seal member 1 of the present embodiment, even if the cylinder (tube) 2 is made of an aluminum alloy that is softer than the case where the cylinder (tube) 2 is made of steel, the tube end of the cylinder 2 is fixed as described above. Since the crimped portion 2a formed by crimping is in close contact with the outer peripheral portion of the outer end 11a of the insert metal 11, strength is guaranteed. Therefore, according to the fixing structure of the sealing member 1 of the present embodiment, the fixing structure of the sealing member 1 is applied while ensuring the strength even if the cylinder (tube) 2 is made of an aluminum alloy which is softer than steel. It is possible to reduce the weight of the shock absorber D and the like.

Furthermore, the method of fixing the seal member 1 according to the present embodiment includes the annular insert metal 11 and the inner peripheral seal portion (seal portion) 12 and the outer peripheral seal portion (seal portion) 13 provided integrally with the insert metal 11. A seal member 1 for sealing the inside of the cylinder (tube) 2 by fitting the outer periphery of the insert metal 11 to the inner periphery of the cylinder (tube) 2 is caulked to the inner periphery side of the tube end of the cylinder (tube) 2. A stepped portion 11b formed to the outermost periphery of an outer end 11a of an insert metal 11 facing outward with respect to a cylinder (tube) 2 and a stepped portion 11b. A seal member 1 provided with a chamfered portion 11c having an axial length L1 longer than the axial length L2 of the stepped portion 11b on the outer periphery is inserted into the cylinder (tube) 2, and the pipe of the cylinder (tube) 2 is inserted. The fixing method is to fix the sealing member 1 to the cylinder (tube) 2 by crimping the end to the inner peripheral side.

According to the fixing method of the sealing member 1 configured in this way, since the axial length L1 of the chamfered portion 11c is longer than the axial length L2 of the stepped portion 11b, the pipe end of the cylinder (tube) 2 is is crimped to form the crimped portion 2a, the crimped portion 2a is deformed following the chamfered portion 11c on the outer periphery of the outer end 11a of the insert metal 11 without being affected by the stepped portion 11b. As a result, the inner circumference at the starting point of the bending of the caulked portion 2a on the outer circumference of the insert metal 11 is brought into close contact with the insert metal 11 without peeling off. Therefore, according to the fixing method of the seal member 1 of the present embodiment, the caulked portion 2a of the cylinder (tube) 2 is not peeled off and adheres closely to the insert metal 11, so that the strength of the caulked portion 2a is not lowered. Therefore, good sealing performance of the sealing member 1 can be ensured.

Furthermore, the shock absorber D in the present embodiment includes a rod 3 inserted axially movably into a cylinder (tube) 2 and an annular shape fitted to the inner periphery of the cylinder (tube) 2 and A rod guide 4 that slides on the outer circumference of the rod 3 to guide the movement of the rod 3, an annular insert metal 11 fitted to the inner circumference of the cylinder (tube) 2, and the insert metal 11 are integrally provided on the inner circumference side of the insert metal 11. The rod guide 4 has an inner peripheral seal portion 12 which is mounted and is in sliding contact with the outer periphery of the rod 3 and an outer peripheral seal portion 13 which is integrally provided on the outer peripheral side of the insert metal 11 and is in contact with the inner periphery of the cylinder (tube) 2. and a seal member 1 that seals the inside of the cylinder (tube) 2 by contacting the insert metal 11 with the outer end 4a facing outward with respect to the cylinder (tube) 2 of the cylinder (tube) 2. and a chamfered portion 11c provided on the outer periphery of the stepped portion 11b at the outer end 11a and the chamfered portion The axial length L1 of 11c is longer than the axial length L1 of the step portion 11b, and the sealing member 1 is fixed to the cylinder (tube) 2 by crimping the pipe end of the cylinder (tube) 2 toward the inner peripheral side. .

According to the shock absorber D configured in this way, since the axial length L1 of the chamfered portion 11c is longer than the axial length L2 of the stepped portion 11b, the tube end of the cylinder (tube) 2 is caulked. Then, the caulked portion 2a is deformed following the chamfered portion 11c on the outer periphery of the outer end 11a of the insert metal 11 without being affected by the stepped portion 11b. 11, the inner circumference of the starting point of the bending of the caulked portion 2a adheres to the insert metal 11 without peeling off. Therefore, according to the shock absorber D of the present embodiment, the caulked portion 2a of the cylinder (tube) 2 is not peeled off and adheres closely to the insert metal 11, so that the strength of the caulked portion 2a is not lowered. Since the sealing member 1 maintains good sealing performance, a stable damping force can be exhibited over a long period of time.

As described above, since the shock absorber D of this embodiment is a single cylinder shock absorber, the cylinder 2 is a tube. The tube may be an outer tube that forms a reservoir between itself and the cylinder. Further, it is sufficient that the outer end 11a of the insert metal 11 in the sealing member 1 is provided with the stepped portion 11b and the chamfered portion 11c. The location, shape, and number of seals to be installed can be appropriately changed in design. In addition, the fixing structure and fixing method of the sealing member 1 according to the present invention can be applied to fluid pressure actuators and other fluid pressure devices other than the shock absorber D. In the description of the shock absorber D, the working fluid is described as liquid, but only gas may be used as the working fluid. The working fluid in pressure equipment is not limited to liquid.

Although preferred embodiments of the invention have been described in detail above, modifications, variations, and changes are possible without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 1... Sealing member 2... Cylinder (tube) 3... Rod 4... Rod guide 4a... Outer end of rod guide 11... Insert metal 11a... Outer end 11b Stepped portion 11c Chamfered portion 12 Inner peripheral seal portion (seal portion) 13 Outer peripheral seal portion (seal portion) D Shock absorber L1: Axial length of the chamfered portion, L2: Axial length of the stepped portion,

Claims (4)

A sealing member having an annular insert metal and a sealing portion provided integrally with the insert metal and sealing the inside of the tube by fitting the outer periphery of the insert metal to the inner periphery of the tube is provided at the tube end of the tube. A sealing member fixing structure that is fixed by crimping to the inner peripheral side,
The insert metal has a stepped portion provided by an annular recess formed up to the outermost periphery on the outer peripheral side of the outer end facing outward with respect to the tube, and a chamfered portion provided on the outer periphery of the stepped portion at the outer end. and
The fixing structure of the sealing member, wherein the axial length of the chamfered portion is longer than the axial length of the stepped portion. The sealing member fixing structure according to claim 1, wherein the tube is made of an aluminum alloy. A sealing member having an annular insert metal and a sealing portion provided integrally with the insert metal and sealing the inside of the tube by fitting the outer periphery of the insert metal to the inner periphery of the tube is provided at the tube end of the tube. A method of fixing a seal member by crimping to the inner peripheral side to fix,
A stepped portion formed to the outermost periphery on the outer end of the insert metal facing outward with respect to the tube, and a surface having an axial length longer than the axial length of the stepped portion on the outer periphery of the stepped portion. inserting a seal member provided with a cut portion into the tube;
A method of fixing a sealing member, comprising: fixing the sealing member to the tube by crimping the tube end of the tube toward the inner peripheral side. a rod axially movably inserted into the tube;
an annular rod guide that is fitted to the inner periphery of the tube and slidably contacts the outer periphery of the rod to guide movement of the rod;
An annular insert metal to be fitted to the inner periphery of the tube, an inner peripheral sealing portion integrally provided on the inner peripheral side of the insert metal and slidably contacting the outer periphery of the rod, and an integral seal portion on the outer peripheral side of the insert metal. and an outer peripheral seal portion that abuts on the inner periphery of the tube, and seals the inside of the tube by bringing the insert metal into contact with the outer end of the rod guide that faces outward with respect to the tube and a sealing member;
The insert metal has a stepped portion provided by an annular recess formed up to the outermost periphery on the outer peripheral side of the outer end facing outward with respect to the tube, and a stepped portion provided on the outer periphery of the stepped portion at the outer end. and a chamfered portion,
the axial length of the chamfered portion is longer than the axial length of the stepped portion;
A shock absorber, wherein the seal member is fixed to the tube by crimping the tube end of the tube inwardly.

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