JP6326298B2 - shock absorber - Google Patents

Description

  The present invention relates to a shock absorber.

  Patent Document 1 discloses a twin-tube shock absorber in which a cylindrical diaphragm is provided on the outer periphery of an inner tube and an air chamber is defined in a reservoir.

  In the above shock absorber, gas is sealed in the air chamber. For this reason, even when the shock absorber is installed sideways, gas can be prevented from being mixed into the inner tube.

JP2012-193824A

  When the shock absorber is extended, working fluid corresponding to the volume of the piston rod retracted from the inner tube is supplied from the reservoir into the inner tube, and the gas in the air chamber expands. Further, at the time of contraction, hydraulic oil corresponding to the volume of the piston rod that has entered the inner tube is discharged from the inner tube to the reservoir, and the gas in the air chamber contracts.

  The diaphragm is formed of a material having excellent elasticity such as rubber so as not to hinder gas expansion and contraction. For this reason, for example, when the total length of the shock absorber is increased to increase the stroke and the total length of the diaphragm is increased accordingly, or when the diaphragm plate thickness is decreased to increase the volume of the air chamber, The diaphragm itself is easily bent by its own weight.

  In a shock absorber provided with such a diaphragm, it is considered that the volume of the air chamber cannot be secured as intended if the diaphragm is bent by its own weight during assembly.

  The present invention has been made in view of such a technical problem, and an object of the present invention is to suppress the deflection of the diaphragm toward the air chamber during assembly.

The present invention is a shock absorber, an inner tube filled with a working fluid, and an outer tube disposed so as to cover the inner tube and forming a reservoir for storing the working fluid between the inner tube and the inner tube. A piston that is slidably inserted into the inner tube and divides the inner tube into an extension side chamber and a pressure side chamber; a piston rod that is slidably inserted into the inner tube and connected to the piston; and is fitted to the inner periphery of the outer peripheral or the outer tube of the inner tube, and a tubular diaphragm having to stretch defining an air chamber in which the gas is enclosed in the reservoir, the air of the diaphragm the surface of the chamber side, the outer periphery of the inner tube spaced from the end of the diaphragm or the Autachi Convex portion is provided to abut against the inner periphery of the over blanking, characterized in that.

  According to the present invention, the convex portion is provided on the surface on the air chamber side of the diaphragm so as to be separated from the end portion of the diaphragm. When the diaphragm is fitted on the outer periphery of the inner tube, the air chamber is formed between the diaphragm and the inner tube, and the convex portion abuts on the outer periphery of the inner tube. Further, when the diaphragm is fitted on the inner periphery of the outer tube, an air chamber is formed between the diaphragm and the outer tube, and the convex portion abuts on the inner periphery of the outer tube. Thereby, the bending to the air chamber side of the diaphragm at the time of an assembly | attachment is suppressed. Therefore, the volume of the air chamber can be ensured as intended.

It is sectional drawing of the shock absorber which concerns on 1st Embodiment of this invention. It is II-II sectional drawing of FIG. It is sectional drawing of the shock absorber which concerns on 2nd Embodiment of this invention. It is IV-IV sectional drawing of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
The shock absorber 100 according to the first embodiment of the present invention is interposed, for example, horizontally between a beam and a pillar constituting a framework of a house, and generates a damping force to suppress the vibration of the house due to an earthquake. Device.

  As shown in FIG. 1, the shock absorber 100 is provided with an inner tube 1 filled with hydraulic oil as a hydraulic fluid, and a reservoir that covers the inner tube 1 and stores hydraulic oil between the inner tube 1. 110, an outer tube 2 that forms 110, and an inner tube 1 that is slidably inserted into the inner tube 1, a piston 3 that divides the inner tube 1 into an extension side chamber 120 and a pressure side chamber 130, and an inner tube 1 that is movably inserted into the inner tube 1, A piston rod 4 connected to the piston 3 and a cylindrical diaphragm 5 which is fitted on the outer periphery of the inner tube 1 and defines an air chamber 140 in the reservoir 110 are provided. The air chamber 140 is filled with atmospheric air.

  A rod guide 7 that slidably supports the piston rod 4 via a bush 6 is attached to the end of the inner tube 1 on the extension side chamber 120 side. A valve mechanism 8 is attached to the end of the inner tube 1 on the pressure side chamber 130 side.

  In the outer tube 2, the end on the extension side chamber 120 side is closed by the cap member 9, and the end on the compression side chamber 130 side is closed by the bottom member 10. The cap member 9 and the bottom member 10 are fixed to the outer tube 2 by welding.

  The inner tube 1 is sandwiched between the cap member 9 and the bottom member 10 together with the rod guide 7 and the valve mechanism 8.

  The cap member 9 is annular and the piston rod 4 is inserted therethrough. An oil seal 11 is provided between the piston rod 4 and the cap member 9 to prevent hydraulic fluid from leaking to the outside.

  The bottom member 10 is provided with an attachment member 12 for connecting the shock absorber 100 to a bracket (not shown) provided on a beam or a column of a house. Similarly, an attachment member 13 is provided at the end of the piston rod 4 on the side extending from the outer tube 2.

  The valve mechanism 8 includes passages 8 a and 8 b that communicate the pressure side chamber 130 and the reservoir 110.

  The passage 8a is provided with a check valve 14 that opens when the shock absorber 100 is extended to open the passage 8a.

  The passage 8b is provided with a damping valve 15 that opens when the shock absorber 100 is contracted to open the passage 8b and provides resistance to the flow of hydraulic fluid that passes through the passage 8b and moves from the pressure side chamber 130 to the reservoir 110. It is done.

  The piston 3 includes passages 3 a and 3 b that communicate the extension side chamber 120 and the pressure side chamber 130.

  The passage 3a has a damping valve 16 that opens when the shock absorber 100 is extended to open the passage 3a and applies resistance to the flow of hydraulic oil that passes through the passage 3a and moves from the expansion side chamber 120 to the compression side chamber 130. Provided.

  The passage 3b has a damping valve 17 that opens when the shock absorber 100 contracts to open the passage 3b, and applies resistance to the flow of hydraulic fluid that passes through the passage 3b and moves from the compression side chamber 130 to the expansion side chamber 120. Provided.

  The diaphragm 5 is formed of a material having excellent elasticity such as rubber, and the diameter of the end portions 5 a and 5 b is reduced so as to have a tightening margin with respect to the outer diameter of the inner tube 1.

  The diaphragm 5 is held on the outer periphery of the inner tube 1 by the end portions 5 a and 5 b, and forms an air chamber 140 between the inner tube 1 and the diaphragm 5. In addition, fixing rings 18 for preventing the diaphragm 5 from shifting in the axial direction are mounted on the outer circumferences of the both end portions 5a and 5b, respectively. The diaphragm 5 will be described later.

  When the shock absorber 100 is extended so that the piston rod 4 retracts from the inner tube 1, the hydraulic oil passes through the passage 3 a from the expansion side chamber 120 where the volume is reduced by the movement of the piston 3 to the pressure side chamber 130 where the volume is increased. Move. In addition, the hydraulic oil corresponding to the volume of the piston rod 4 withdrawn from the inner tube 1 passes through the passage 8a and is supplied from the reservoir 110 to the pressure side chamber 130, and the air in the air chamber 140 expands.

  At this time, as described above, the shock absorber 100 applies resistance to the flow of the hydraulic oil passing through the passage 3a by the damping valve 16, and generates a differential pressure between the expansion side chamber 120 and the pressure side chamber 130 to generate a damping force. To do.

  When the shock absorber 100 contracts when the piston rod 4 enters the inner tube 1, the hydraulic oil passes through the passage 3 b from the compression side chamber 130 whose volume is reduced by the movement of the piston 3 to the expansion side chamber 120 whose volume is increased. Move. Further, the hydraulic oil corresponding to the volume of the piston rod 4 that has entered the inner tube 1 passes through the passage 8b and is discharged from the pressure side chamber 130 to the reservoir 110, and the air in the air chamber 140 contracts.

  At this time, as described above, the shock absorber 100 gives resistance to the flow of the hydraulic oil passing through the passages 3b and 8b by the damping valves 17 and 15, respectively, and generates a differential pressure between the extension side chamber 120 and the pressure side chamber 130. To generate damping force.

  Next, the diaphragm 5 will be described.

  The diaphragm 5 is formed of a material having excellent elasticity such as rubber so as not to hinder the expansion and contraction of the air enclosed in the air chamber 140. For this reason, for example, in order to increase the stroke, the overall length of the shock absorber 100 is increased, and the total length of the diaphragm 5 is increased accordingly, or the thickness of the diaphragm 5 is decreased in order to increase the volume of the air chamber 140. In this case, the diaphragm 5 itself is easily bent by its own weight due to insufficient rigidity.

  Further, in the shock absorber 100, since the gas sealed in the air chamber 140 is atmospheric pressure air, the volume of the air chamber 140 is the air sealed in the air chamber 140 when the diaphragm 5 is assembled to the inner tube 1. Determined by quantity.

  Therefore, when the diaphragm 5 is assembled to the inner tube 1, if the diaphragm 5 is bent toward the air chamber 140, the amount of air enclosed in the air chamber 140 is reduced, and the volume of the air chamber 140 is reduced. Become.

  On the other hand, in the shock absorber 100, the hydraulic oil stored in the reservoir 110 is supplied to and discharged from the compression side chamber 130, and the air enclosed in the air chamber 140 expands and contracts, so that the inside of the inner tube 1 during operation is expanded. The volume change is compensated. For this reason, it is important to secure the volume of the air chamber 140 so that the air in the air chamber 140 is not completely contracted even when the shock absorber 100 is contracted to the maximum.

  Therefore, in the shock absorber 100 of the present embodiment, as shown in FIGS. 1 and 2, by providing the convex portion 5c on the surface of the diaphragm 5 on the air chamber 140 side, the volume of the air chamber 140 can be secured as intended. I am doing so.

  This will be described in more detail below.

  As shown in FIG. 1, the convex portion 5 c is provided in the central portion of the diaphragm 5 so as to be separated from the end portions 5 a and 5 b.

  The height of the convex portion 5 c is set so as to be in contact with the outer periphery of the inner tube 1 and to ensure a predetermined interval between the surface of the diaphragm 5 on the air chamber 140 side and the outer periphery of the inner tube 1.

  That is, the convex portion 5c supports the central portion of the diaphragm 5 by contacting the outer periphery of the inner tube 1 so that the diaphragm 5 does not bend toward the air chamber 140 side.

  Thereby, the bending to the air chamber 140 side of the diaphragm 5 at the time of assembling | attaching to the inner tube 1 can be suppressed, and the volume of the air chamber 140 can be ensured as aimed.

  As described above, the diaphragm 5 is held on the outer periphery of the inner tube 1 by both end portions 5a and 5b. That is, as for the diaphragm 5, the both ends 5a and 5b serve as support points, and the center portion is bent most greatly. Therefore, by providing the convex portion 5 c at the center of the diaphragm 5, it is possible to effectively suppress the deflection of the diaphragm 5.

  Since the convex portion 5c is provided so as to protrude into the air chamber 140, the volume of the air chamber 140 is reduced by the volume of the convex portion 5c itself. Therefore, as described above, by providing the convex portions 5c at positions where the deflection of the diaphragm 5 can be effectively suppressed, the number and size of the convex portions 5c can be suppressed, and the volume of the air chamber 140 can be easily secured. .

  Moreover, in this embodiment, as shown in FIG. 2, the four convex parts 5c are provided in the circumferential direction of the diaphragm 5 at equal intervals. According to this, even when the diaphragm 5 is rotated around the axis when the diaphragm 5 is assembled to the inner tube 1, the deflection of the diaphragm 5 toward the air chamber 140 is caused by any one of the convex portions 5 c located above. Can be suppressed.

  As long as the volume of the air chamber 140 can be ensured, the number of the convex parts 5c of the circumferential direction may be 5 or more, for example, and may be 3 or less. When reducing the number of the convex portions 5c, for example, by providing the convex portions 5c so as to extend in the circumferential direction, even if the diaphragm 5 is rotated around the axis, a part of the convex portions 5c is positioned upward. You can do that.

  Moreover, in order to suppress the bending of the diaphragm 5, the convex part 5c should just be provided in the position where the bending of the diaphragm 5 generate | occur | produces. As described above, the diaphragm 5 bends with the end portions 5a and 5b serving as support points. Therefore, if the convex portion 5c is provided apart from the end portions 5a and 5b, the effect of suppressing the deflection of the diaphragm 5 can be obtained. Can be obtained. Therefore, as long as the volume of the air chamber 140 can be secured, the convex portion 5 c may be provided in addition to the central portion of the diaphragm 5.

  Further, if a plurality of convex portions 5 c are provided in the axial direction of the diaphragm 5, the deflection of the diaphragm 5 can be further suppressed.

  As described above, according to the present embodiment, the convex portion 5 c provided on the surface of the diaphragm 5 on the air chamber 140 side so as to be separated from the end portions 5 a and 5 b abuts on the outer periphery of the inner tube 1. Thereby, the bending to the air chamber 140 side of the diaphragm 5 at the time of assembling | attaching to the inner tube 1 can be suppressed, and the volume of the air chamber 140 can be ensured as aimed.

  Moreover, since both ends 5a and 5b serve as support points, the center portion of the diaphragm 5 is bent most greatly. For this reason, by providing the convex part 5c in the center part of the diaphragm 5, the bending of the diaphragm 5 can be suppressed effectively, suppressing the number and magnitude | size of the convex part 5c.

Second Embodiment
Subsequently, a shock absorber 200 according to a second embodiment of the present invention will be described with reference to FIGS. 3 and 4.

  The shock absorber 200 is different from the shock absorber 100 in the diaphragm. Hereinafter, description will be made centering on differences from the shock absorber 100, and the same components as those in the first embodiment will be denoted by the same reference numerals, and description thereof will be omitted.

  As shown in FIG. 3, the shock absorber 200 of the present embodiment has the diaphragm 19 fitted on the inner periphery of the outer tube 2.

  The diaphragm 19 is formed of a material having excellent elasticity such as rubber, and the diameter of the end portions 19 a and 19 b is increased so as to have a tightening margin with respect to the inner diameter of the outer tube 2.

  The diaphragm 19 is held on the inner periphery of the outer tube 2 by the end portions 19 a and 19 b, and forms an air chamber 140 with the outer tube 2. In addition, fixing rings 20 for preventing the diaphragm 19 from being displaced in the axial direction are mounted on the inner circumferences of both end portions 19a and 19b, respectively.

  On the surface of the diaphragm 5 on the air chamber 140 side, a convex portion 19c is provided at the center of the diaphragm 19 apart from the end portions 19a and 19b.

  The height of the convex portion 19 c is set so as to be in contact with the inner periphery of the outer tube 2 and to ensure a predetermined interval between the surface of the diaphragm 19 on the air chamber 140 side and the inner periphery of the outer tube 2. The

  That is, the convex portion 19c supports the center portion of the diaphragm 19 by contacting the inner periphery of the outer tube 2 so that the diaphragm 19 does not bend toward the air chamber 140.

  Thereby, the bending to the air chamber 140 side of the diaphragm 19 at the time of assembling | attaching to the outer tube 2 can be suppressed, and the volume of the air chamber 140 can be ensured as aimed.

  As shown in FIG. 4, four convex portions 19 c are provided at equal intervals in the circumferential direction of the diaphragm 19. According to this, even when the diaphragm 19 is rotated around the axis when the diaphragm 19 is assembled to the outer tube 2, the deflection of the diaphragm 19 toward the air chamber 140 side is caused by any one of the convex portions 19 c positioned below. Can be suppressed.

  According to the said structure, the effect similar to 1st Embodiment can be acquired.

  As mentioned above, although embodiment of this invention was described, the said embodiment showed only a part of application example of this invention, and is not the meaning which limits the technical scope of this invention to the specific example of said embodiment. .

  For example, in the above embodiment, the shock absorbers 100 and 200 are applied to a house, but may be applied to other buildings, vehicles such as automobiles and railways, and the like.

  Moreover, in the said embodiment, although the shock absorbers 100 and 200 are installed horizontally, you may install vertically and may install diagonally.

  Moreover, in the said embodiment, although hydraulic oil is used as a hydraulic fluid, you may use other liquids, such as water.

  In the above embodiment, atmospheric pressure air is sealed in the air chamber 140, but pressurized air may be sealed. Moreover, you may enclose gas other than air.

DESCRIPTION OF SYMBOLS 100 Shock absorber 110 Reservoir 120 Extension side chamber 130 Pressure side chamber 140 Air chamber 1 Inner tube 2 Outer tube 3 Piston 4 Piston rod 5 Diaphragm 5a End part 5b End part 5c Convex part 200 Shock absorber 19 Diaphragm 19a End part 19c End part 19b End part 19b End part 19b

Claims (2)

A shock absorber,
An inner tube filled with hydraulic fluid;
An outer tube disposed over the inner tube and forming a reservoir for storing the hydraulic fluid between the inner tube;
A piston that is slidably inserted into the inner tube and divides the inner tube into an extension side chamber and a compression side chamber;
A piston rod which is inserted into the inner tube so as to freely advance and retract, and is connected to the piston;
Said is fitted to the inner periphery of the outer peripheral or the outer tube of the inner tube, tubular diaphragm having a gas to define a gas chamber to be sealed stretchability in said reservoir,
With
On the surface of the diaphragm on the air chamber side, a convex portion that is spaced apart from the end of the diaphragm and contacts the outer periphery of the inner tube or the inner periphery of the outer tube is provided.
Shock absorber characterized by that. The shock absorber according to claim 1,
The convex portion is provided at a central portion in the axial direction of the diaphragm.
Shock absorber characterized by that.

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