JP2010127444A - Seal member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal member capable of reducing weight and improving economical efficiency without impairing a sealing function. <P>SOLUTION: The seal member S is laminated on an annular rod guide 4 suitable for the opening end of a container 2 and seals the outer periphery of the rod 3 so supported in the rod guide 4 as to advance and retreat in the container 2. The seal member includes a seal body 10 having an insert metal 12 with an annular shape and an outer diameter set to be smaller than the inside diameter of the container 2 while permitting the rod 3 to be inserted into the inside thereof, and a seal lip 13 having an annular shape, sliding on the outer periphery of the rod 3, and being held in the insert metal 12, and an annular seal holder 11 which is laminated on the rod guide 4 and secured to the container 2 while having the inner periphery to which the seal body 10 is fitted. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a seal member.

In a conventional seal member, for example, a cylinder of a double cylinder type hydraulic shock absorber is laminated on an annular rod guide that fits into an open end of an outer cylinder, and is pivotally supported by the rod guide in the cylinder. It is known to seal the outer periphery of the rod that is advanced and retracted. Specifically, a perforated disc-shaped insert metal that is stacked on the rod guide and the inner periphery of the insert metal that slides on the outer periphery of the rod. An oil lip and a dust lip that are in contact with each other, and an outer peripheral seal that is held on the outer periphery of the insert metal and is inserted into an annular notch provided on the outer periphery of the rod guide to seal the inner periphery of the outer cylinder, The inside of the cylinder is kept oil-tight (for example, see Patent Document 1).
JP 2007-120514 A

  The sealing member has no problem in terms of function, but there is room for improvement in the following points.

  Because the insert metal of the seal member is set to a thickness that can withstand the caulking load, keeping in mind that the open end of the cylinder or the outer cylinder is fixed. The seal member as a whole is not only heavy but also expensive, and there is a demand for light weight and improved economy.

  Also, the integration of rubber materials such as oil seals, dust seals and outer periphery seals with metal insert metal is an insert molding in which high-temperature rubber is injected into a mold in which the insert metal is inserted in advance and the rubber is welded to the insert metal. However, if the hydraulic equipment is a single cylinder type, the outer diameter of the insert metal is set to the same diameter as the cylinder inner diameter. If the hydraulic equipment is a multi-cylinder type, the outer diameter of the insert metal is the same as the inner diameter of the outer cylinder that covers the cylinder. Since the diameter is set, the outer diameter is large and the number of seal members that can be molded with one set of insert molding dies is small, and it is required before insert molding such as the degreasing process of the insert metal and the adhesive application process. Processing takes time and processing costs are high, and in this respect also, improvement in economic efficiency is desired.

  Therefore, the present invention has been developed to improve the above-mentioned problems, and the object of the present invention is to provide a sealing member that can be reduced in weight and cost without impairing the sealing function. Is to do.

  In order to solve the above-described object, the problem-solving means in the present invention includes a rod that is stacked on an annular rod guide that fits into the open end of a container, is supported by the rod guide, and is advanced and retracted into the container. In the seal member that seals the outer periphery, it is annular and the outer diameter is set smaller than the inner diameter of the container, and the insert metal that allows the insertion of the rod into the inner side is annular and slides on the outer periphery of the rod and is held by the insert metal A seal body having a seal lip, and an annular seal holder that is stacked on the rod guide and fixed to the container, and the seal body is fitted to the inner periphery.

The seal body includes a seal body having a seal lip that is held by an insert metal, and an annular seal holder that is stacked on the rod guide and fixed to the container, and the seal body is fitted to the inner periphery. With the same sealing function, the insert metal is reduced in diameter and size to speed up the degreasing and adhesive application operations, and the number of molds that can be taken with one set of molds for insert molding is increased, resulting in efficient production. Can do.
In addition, the total weight of the seal body and the seal holder is lighter than that of a conventional seal member in which the insert metal has to be thick, and this also reduces the cost.

  Therefore, according to the sealing member of the present invention, it is possible to reduce the weight and improve the economy without impairing the sealing function.

  Hereinafter, the sealing member of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a head portion of a multi-cylinder shock absorber to which a seal member according to an embodiment is applied. Drawing 2 is a figure explaining the process of enclosing gas to the double cylinder type buffer which applied the seal member in one embodiment. FIG. 3 is a longitudinal sectional view of a head portion of a multi-cylinder shock absorber to which a seal member according to a modification of the embodiment is applied.

  As shown in FIG. 1, the sealing member S in one embodiment is embodied in the upper end portion of the cylinder 1 as the head portion of the hydraulic shock absorber, with the container as the outer cylinder 2 of the shock absorber. Specifically, the hydraulic shock absorber is disposed outside the cylinder 1, the outer cylinder 2 that covers the cylinder 1 and closes the opening end of the cylinder 1 and the opening end of the outer cylinder 2, and the cylinder 1. A rod guide 4 that pivotally supports a rod 3 that is movably inserted therein, and a seal member S is stacked on the rod guide 4 and fixed to the outer cylinder 2 to seal the outer periphery of the rod 3.

  Also, below the cylinder 1, although not shown, a piston connected to the lower lower end of the rod 3 is slidably inserted, and the rod side chamber R1 filled with hydraulic oil in the cylinder 1 by this piston. A piston-side chamber (not shown) is partitioned, and a reservoir R filled with gas and hydraulic oil is formed between the cylinder 1 and the outer cylinder 2. That is, this shock absorber is configured as a so-called double-tube shock absorber. In the above description, the shock absorber is a hydraulic shock absorber using hydraulic oil as a working fluid, but the working fluid may be another liquid or a gas.

  Subsequently, the rod guide 4 is formed in an annular shape, and is provided so that a convex portion 4a protrudes downward from the lower end in FIG. 1, and the convex portion 4a serves as an upper end in FIG. And the upper end of the cylinder 1 is closed. Moreover, the rod guide 4 is inserted in the inner peripheral side of the opening end used as the upper end in FIG. 1 of the outer cylinder 2, and also obstruct | occludes the upper end of the outer cylinder 2. FIG.

  The outer periphery of the rod guide 4 is provided with an annular groove 4b formed over the entire circumference, and the rod guide 4 and the outer cylinder are in close contact with the inner periphery of the outer cylinder 2 in the annular groove 4b. A seal ring 5 that seals between the two is mounted.

  Further, a cylindrical bearing 6 is mounted on the inner periphery of the rod guide 4, and the rod 3 is slidably inserted into the bearing 6. Further, a concave portion 4c and a step portion 4d connected to the outer peripheral portion of the concave portion 4c are provided on the inner peripheral side of the upper end in FIG. 1 of the rod guide 4, and faces the reservoir R of the rod guide 4 from the outer edge of the step portion 4d. A communication hole 4e that communicates up to the surface is provided.

  Subsequently, the seal member S stacked above the rod guide 4 in FIG. 1 includes a seal body 10 and a seal holder 11 as shown in FIGS. 1 and 2. The seal body 10 is annular and has an outer diameter that is smaller than the inner diameter of the outer cylinder 2, and an annular insert metal 12 that allows insertion of the rod 3 inward. The seal body 10 is annular and slidably contacts the outer periphery of the rod 3. A seal lip 13 held by the insert metal 12, a ring-shaped dust strip 14 which is in sliding contact with the outer periphery of the rod 3 and held by the insert metal 12, and an annular seal 15 integrated with the outer periphery of the insert metal 12. And is configured.

  More specifically, the insert metal 12 includes a cylindrical portion 12a that fits on the inner periphery of the seal holder 11, and a flange 12b that extends from the upper end of the cylindrical portion 12a to the inner peripheral side in FIG. The seal lip 13 is integrated and held on the lower side which is the rod guide side from the flange 12b of the insert metal 12, and the dust lip 14 is the upper side which is on the side opposite to the rod guide from the flange 12b of the insert metal 12. Are integrated and held.

  Further, the seal holder 11 includes an annular plate 11a which is laminated on the upper surface of the rod guide 4 in FIG. 1 and is fixed to the outer cylinder 2 by caulking the tube end of the outer cylinder 2 as a container, and a rod from the inner periphery of the annular plate 11a. A cylindrical socket 11b that rises upward in FIG. 1 in a direction away from the guide 4 and an annular stopper 11c that protrudes inward from the upper end in FIG. 1 on the side opposite to the rod guide of the socket 11b. The outer periphery of the cylindrical portion 12a of the insert metal 12 is fitted to the inner periphery of the socket 11b.

  In this case, for the convenience of fixing the seal holder 11 to the outer cylinder 2, the insert metal 12 only needs to hold the seal lip 13 and the dust lip 14 to be fixed to the outer cylinder 2. The outer diameter can be set smaller than that of a conventional insert metal, and the inner diameter of the socket 11b may be set according to the outer diameter of the insert metal 12. An annular garter spring 16 is attached to the outer periphery of the seal lip 13 to compensate for the tightening force for tightening the rod 3 of the seal lip 13.

  When the seal body 10 thus configured is fitted to the inner periphery of the seal holder 11, the annular seal 15 provided on the outer periphery of the cylindrical portion 12 a of the insert metal 12 is compressed to the inner periphery of the socket 11 b of the seal holder 11. In close contact, the space between the seal body 10 and the seal holder 11 is sealed.

  Further, the seal body 10 is subjected to a force in the direction of pushing upward in FIG. 1 by the action of pressure in the cylinder 1 or the outer cylinder 2, but the socket of the seal holder 11 fixed by caulking the outer cylinder 2. Since the stopper 11c provided at the upper end of 11b restricts the upward movement of the seal body 10, the seal body 10 is prevented from falling off the shock absorber.

  Therefore, when the seal member S is laminated on the rod guide 4 and fixed to the outer cylinder 2, the seal lip 13 of the seal member S comes into sliding contact with the outer periphery of the rod 3 with a pressing force, and the outer periphery of the rod 3 is sealed. The Further, since the outer periphery of the rod guide 4 is sealed by the seal ring 5 as described above, the inside of the cylinder 1 of the shock absorber is oil-tightly sealed and the reservoir R between the cylinder 1 and the outer cylinder 2 is sealed. Leakage of gas from is also prevented.

  The shape of the insert metal 12 may be a shape in which the flange 12b is provided at the lower end in FIG. 1 of the cylindrical portion 12a, and may have a rectangular cross section, but as described above, the cylindrical portion 12a. And the flange 12b are advantageous in that the weight can be reduced while functioning as the core metal of the seal lip 13 and the dust lip 14.

  Further, as described above, the seal holder 11 is laminated on the upper surface of the rod guide 4 in FIG. 1 and is fixed by crimping the tube end of the outer cylinder 2, but the seal on the outer periphery of the rod guide 4 is used as the seal ring 5. The rod guide 4 has an opening on the outer periphery of the upper end surface like the rod guide in the prior art, and there is no notch into which the outer periphery seal is inserted, so that the outer cylinder 2 is formed on the upper end surface of the rod guide 4. It is not necessary to receive the caulking load by increasing the wall thickness of the seal holder 11.

  Further, the seal lip 13 is at least smaller than the inner diameter of the outer cylinder 2 and is integrated with the insert metal 12 which is smaller in diameter and smaller than the insert metal of the conventional seal member. The degreasing and adhesive application work time is also shortened, and the mold area is the same when the insert lip 13 is welded and integrated with the insert metal 12 for insert molding. If this is the case, the number of molds that can be obtained with one set of molds is greater than that of the conventional seal member, and the seal holder 11 does not need to be integrated with the seal. Therefore, the seal member S can be manufactured efficiently and the manufacturing cost can be reduced. Reduced.

  Further, the seal holder 11 can be easily formed by press working by adopting the shape as described above, and even if the seal member S is a two-piece of the seal body 10 and the seal holder 11, the manufacturing cost is increased. There is no invitation.

  Therefore, by forming the seal member S with the seal body 10 and the seal holder 11, the seal body 10 and the seal holder 11 can be compared with a conventional seal member in which the insert metal has to be thick. The total weight is light and manufacturing costs are reduced.

  Subsequently, the seal member S is applied to a double cylinder type shock absorber, and it is necessary to enclose gas into the reservoir R in order to manufacture the double cylinder type shock absorber. Here, in order to enclose the gas into the reservoir using the conventional seal member, the seal member is not completely stacked on the rod guide, but is fitted in the outer cylinder in a slightly floated state so that the tube of the outer cylinder is fitted. The end is temporarily swaged to prevent the seal member from coming off, and the outer peripheral seal of the seal member is not completely brought into close contact with the annular notch provided on the outer periphery of the rod guide. A process of sealing between the outer cylinder and the reservoir, and after sealing the gas, completely seals the seal member to the rod guide and fully crimps the tube end of the outer cylinder.

  On the other hand, the sealing member S described above is constituted by a two-piece part of the seal body 10 and the seal holder 11, and the seal body 10 is pushed into the recess 4c side of the rod guide 4 as shown in FIG. With the gap formed between the seal holder 11 and the seal holder 11, the seal holder 11 is completely stacked on the rod guide 4, and the tube end of the outer cylinder 2 is crimped and fixed, and gas is injected from the gap. Then, the gas can be sent into the reservoir R through the communication hole 4 e of the rod guide 4. When the seal body 10 is pushed into the recess 4c and gas is injected into the reservoir R, the seal member S is pressed by the injected gas, and the seal lip 13 is in close contact with the upper surface of the recess 4c in FIG. Therefore, the gas can be injected only into the reservoir R and is not injected into the cylinder 1.

  When the injection of a predetermined amount of gas into the reservoir R is completed, the seal body 10 is pushed upward in FIG. 2 by the pressure in the outer cylinder 2 and the cylinder 1 and enters the socket 11b of the seal holder 11 to fit. Then, the seal body 10 stays in the socket 11b by the stopper 11c, and the annular seal 15 comes into close contact with the inner periphery of the socket 11b to automatically seal the inside of the cylinder 1 and the outer cylinder 2.

  As described above, when the seal member S of the present embodiment is applied to the seal around the rod 3 of the double-cylinder shock absorber, when the gas is sealed in the reservoir R, the tube end crimping step of the outer cylinder 2 and the reservoir R It is possible to separate the gas filling process.

  That is, when gas is sealed in a reservoir using a conventional seal member, the caulking process of the outer cylinder and the gas sealing process cannot be separated, and the gas is processed using a processing apparatus capable of performing both processes simultaneously. Since the sealing is performed, the processing apparatus is large and has a complicated structure, and the maintenance becomes complicated. On the other hand, by using the seal member S of the present embodiment, as described above, the tube end of the outer cylinder 2 is swaged and the seal holder 11 is completely fixed, and then the gas is sealed. Therefore, there is an advantage that both processes can be completely separated, the caulking apparatus is not enlarged and complicated, and maintenance is easy.

  When the shock absorber includes the reservoir R, when the rod 3 enters the cylinder 1, the gas in the reservoir R passes between the rod 3 and the bearing 6 and is decompressed. In order to prevent the hydraulic oil adhering to the rod 3 from being scraped off by the reel lip 13 and stored in the concave portion 4c of the rod guide 4 while accumulating pressure in the concave portion 4c A seal may be provided.

  In the case where the check seal is provided in this way, as shown in FIG. 3, a flange portion 12c protruding outward is provided at the lower end of the cylindrical portion 12a of the insert metal 12, and an annular check seal 17 is provided on the flange portion 12c. It is good to form.

  The check seal 17 is formed into an annular shape, and the insert metal 12 is insert-molded as an insert, so that the check seal 17 is integrated with the flange portion 12c of the insert metal 12 and extends from the flange portion 12c, and the tip thereof is a step portion 4d of the rod guide 4. The tip is pressed against the step 4d by its own elastic force.

  Since the check seal 17 is bent to generate a resilient force and the tip thereof is in contact with the step portion 4d of the rod guide 4, the check seal 17 is sealed in the reservoir R through the communication hole 4e. While preventing the gas from flowing into the recess 4c, conversely, when hydraulic oil or gas accumulates in the recess 4c and the pressure in the recess 4c rises, it bends away from the step 4d and moves the hydraulic oil to the reservoir R. Demonstrate the ability to escape.

  Thus, even if the seal body 10 and the seal holder 11 are separated, the check seal 17 can be provided on the insert metal 12, and the seal member S is required for the seal member of the shock absorber set to a double cylinder type. The function to be performed can be fully exhibited.

  In the above description, the case where the seal member S is applied to the head portion of the double cylinder type hydraulic shock absorber has been described. However, the working fluid of the shock absorber is a gas even if it is a liquid other than the hydraulic oil. In addition, the inside of the cylinder and the outer cylinder can be sealed, the weight can be reduced and the manufacturing cost can be reduced, and the seal member S can be applied.

  Further, in the above description, the sealing member S has the dust strip 14 integrated with the insert metal 12, but this can be omitted if the dust strip 14 is not required.

  Further, as described above, the seal member S has an excellent advantage of facilitating gas sealing by being applied to a double-tube shock absorber, but can also be applied to a single-tube shock absorber. In this case, the container referred to in the claims is a cylinder, and the outer diameter of the insert metal may be set smaller than the inner diameter of the cylinder. Furthermore, the seal member S can also be used as a seal member for equipment other than a shock absorber such as a cylinder device or a stay damper.

 It should be noted that the scope of the present invention is not limited to the details shown or described.

It is a longitudinal cross-sectional view of the head part of the double cylinder type shock absorber to which the seal member in one embodiment is applied. It is a figure explaining the process of enclosing gas into the double cylinder type buffer which applied the seal member in one embodiment. It is a longitudinal cross-sectional view of the head part of the double cylinder type buffer which applied the seal member in one modification of one embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder 2 Outer cylinder 3 Rod 4 Rod guide 4a Convex part 4b in a rod guide Annular groove 4c in a rod guide 4d Concave part 4d in a rod guide 4e Step part in a rod guide 5 Communication hole 5 in a rod guide 5 Seal ring 6 Bearing 10 Seal body 11 Seal holder 12 insert metal 12a cylindrical portion 12b in insert metal flange 12c in insert metal flange 13c in insert metal 13 seal lip 14 dust lip 15 annular seal 16 garter spring 17 check seal R reservoir R1 rod side chamber S seal member

Claims (6)

A sealing member that is stacked on an annular rod guide that fits into the open end of the container and seals the outer periphery of the rod that is pivotally supported by the rod guide and advances and retracts into the container. A seal body having a smaller diameter and allowing insertion of the rod into the inner side, an annular shape that is in sliding contact with the outer periphery of the rod and held by the insert metal, and laminated on the rod guide A seal member comprising: an annular seal holder fixed to a container and fitted with a seal main body on an inner periphery thereof. The insert metal includes a cylindrical portion that fits on the inner periphery of the seal holder, and a flange that extends from one end of the cylindrical portion to the inner peripheral side, and a seal lip is provided on the rod guide side from the flange of the insert metal. The seal member according to claim 1, further comprising a dust lip slidably contacting the outer periphery of the rod on the side opposite the rod guide from the flange. The seal holder rises in a direction away from the rod guide from the inner periphery of the annular plate, which is laminated to the rod guide and fixed to the container by a nut tightened on the tube end of the container or screwed to the inner periphery of the container. It is configured with a cylindrical socket and an annular stopper that protrudes inward from the end of the socket opposite to the rod guide, and the stopper restricts the movement of the seal body in the direction away from the rod guide. The sealing member according to claim 1 or 2, characterized in that The seal member according to any one of claims 1 to 3, wherein an annular seal is provided on the outer periphery of the insert metal so as to be in close contact with the inner periphery of the seal holder and seal between the insert metal and the seal holder. The container includes an outer cylinder that forms a reservoir that covers the outer periphery of the cylinder and compensates for a change in the volume in the cylinder due to the rod moving forward and backward between the cylinder and the seal holder. The seal structure according to any one of claims 1 to 4, wherein the reservoir is filled with gas through a space between the main body and the main body. The seal member according to any one of claims 1 to 5, further comprising an annular check lip that is held by the insert metal and pressed against and contacted with an end face of the rod guide facing the insert metal.

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