JP2009085261A - Anti-vibration bush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration isolation bushing keeping the connection state of axial both ends of an inner tube and a stop rubber part satisfactory and exhibiting a stable function of the stop rubber part. <P>SOLUTION: This bushing is provided with a rubber-shaped elastic body 16, an outer tube 14 and an inner tube 12 externally attached to and fixed with a piston rod of a shock absorber. The stop rubber parts 24A, 24B to a stop receive part at a vehicle body side arranged at axial both outer sides of the inner tube 12 are attached to both ends in the axial direction of the inner tube 12. The stop rubber parts 24A, 24B are attached to the axial direction ends of the inner tube 12 via an engagement mechanism B comprising an engagement part 24b and an engaged part 16b which are engaged with each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention
An inner cylinder that is extrapolated and fixed to the piston rod of the shock absorber;
An outer cylinder fitted in the fitting hole on the vehicle body side;
A rubber-like elastic body that connects the inner and outer cylinders,
The present invention relates to an anti-vibration bushing in which stopper rubber portions with respect to the stopper receiving portion on the vehicle body side arranged on both outer sides in the axial direction of the inner cylinder are attached to both end portions in the axial direction of the inner cylinder.

  As shown in FIG. 7, in this type of anti-vibration bush A, when the upper and lower stopper rubber portions 24A and 24B are attached to the inner cylinder 12, an adhesive is applied to the flanges 18 formed at both ends in the axial direction of the inner cylinder 12. The stopper rubber portions 24A and 24B were attached to the inner cylinder 12 and fixed.

  However, in this case, since an adhesive is used, the upper and lower stopper rubber parts may be attached to the shaft of the inner cylinder when the adhesive deteriorates during long-term use or adhesion failure is observed during construction. It was easy to peel off from the end of the direction. And when carrying the vibration isolating bush in the state where the stopper rubber portion is attached to the end portion in the axial direction of the inner cylinder, the stopper rubber portion may fall off from the end portion of the inner cylinder.

  The present invention has been made in view of the above circumstances, and its purpose is to prevent the stopper rubber portion from exerting a stable function by improving the connection state between the axial end portions of the inner cylinder and the stopper rubber portion. The point is to provide a swing bush.

[Configuration, Action and Effect of Invention of Claim 1]
〔Constitution〕
The characteristic configuration of the invention according to claim 1 is:
An inner cylinder that is extrapolated and fixed to the piston rod of the shock absorber;
An outer cylinder fitted in the fitting hole on the vehicle body side;
A rubber-like elastic body that connects the inner and outer cylinders,
Anti-vibration bushes attached to both end portions of the inner cylinder in the axial direction with stopper rubber portions for the stopper receiving portions on the vehicle body side arranged on both outer sides in the axial direction of the inner cylinder,
The stopper rubber portion is attached to the end portion in the axial direction of the inner cylinder via an engaging mechanism composed of an engaging portion and an engaged portion that are engaged with each other. Street.

[Action]
Since the stopper rubber portion is attached to the end portion in the axial direction of the inner cylinder via an engagement mechanism including an engagement portion and an engagement portion that are engaged with each other, the engagement portion and the engagement portion are temporarily provided. When engaged, it is difficult to release the engaged state, and it is possible to achieve a retaining effect by the engagement mechanism.
Thereby, when carrying the anti-vibration bush in the state where the stopper rubber portion is attached to the end portion in the axial direction of the inner cylinder, it is possible to avoid the problem that the stopper rubber portion falls off from the inner cylinder.
Moreover, the process of applying an adhesive to both end portions in the axial direction of the inner cylinder is not required, and the manufacturing process can be simplified.
And when an engaging part engages with a to-be-engaged part, since an engagement resistance can be felt to an operator, it becomes easy for an operator to grasp sensuously that the mounting state was completed.

〔effect〕
Accordingly, it is possible to provide a vibration isolating bush that can improve the connection state between the axial end portions of the inner cylinder and the stopper rubber portion, and that the stopper rubber portion can exhibit a stable function.

[Configuration, Action and Effect of Invention of Claim 2]
〔Constitution〕
The characteristic configuration of the invention according to claim 2 is the configuration of the invention according to claim 1,
The engaging portion is a protrusion provided on the stopper rubber portion, and the engaged portion is a protrusion provided on an end portion in the axial direction of the inner cylinder. It is.

[Action]
Both the engaging part and the engaged part are composed of protrusions, and one of the two engages in a state of overcoming the other and exerts a retaining function. Less management is needed.
When one of the engaging portion and the engaged portion gets over the other, the engagement resistance can be felt particularly well by the worker, so that the worker can more sensuously grasp that the wearing state is completed. It becomes easy.

  Therefore, it was possible to provide a vibration-proof bushing that has a strong engagement structure and a small manufacturing burden such as dimensional control.

[Configuration, Action and Effect of Invention of Claim 3]
〔Constitution〕
The characteristic configuration of the invention according to claim 3 is the configuration of the invention according to claim 1,
The engaging portion is a protrusion provided on the stopper rubber portion, and the engaged portion is a side surface of an end portion in the axial direction of the inner cylinder, and its operational effects are as follows. .

[Action]
That is, the stopper rubber portion is mounted by engaging the protrusion with the side surface of the inner cylinder, and the side surface is used as the engaged portion, so that it is not necessary to newly form the engaged portion.

〔effect〕
Thus, the manufacturing cost can be reduced by using the side surface of the inner cylinder also as the engaged portion.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. In the present embodiment, a mode in which the vibration isolating bush is used for an air suspension device will be described.

  As shown in FIGS. 1 and 6, the air suspension device 1 fixes the upper end surface 3 </ b> A of the outer shell 3 to the vehicle body 9 with bolts 8, and shock absorbers in the cylindrical shell lower part 3 </ b> B below the outer shell 3. 2 is arranged, and an anti-vibration bush A is extrapolated to the upper end portion of the piston rod 2 a of the shock absorber 2, and is attached and fixed with a nut 6.

  The outer shell 3 forms an air chamber 7 surrounding the piston rod 2 a, and a cylindrical holder 5 is fixed to the upper part of the outer shell 3. The vibration isolating bush A is held by fitting an outer cylinder 14 (to be described later) of the vibration isolating bush A in which the O-ring 4 is mounted in two upper and lower stages in the cylindrical holder 5.

  A plate-like lower stopper receiving portion 5b for receiving a lower stopper rubber portion 24B of the vibration isolating bushing A from below is provided on the bottom of the cylindrical holder 5, and an anti-vibration is provided on the upper portion of the cylindrical holder 5. A plate-like upper stopper receiving portion 5a for receiving an upper stopper rubber portion 24A (described later) of the bush A from above is provided. That is, the axial displacement of the inner cylinder 12 of the vibration isolating bush A is limited by the stopper receiving portions 5a and 5b.

  As shown in FIGS. 1 and 6, the anti-vibration bush A surrounds the inner cylinder 12 concentrically with a metal inner cylinder 12 that is externally attached and fixed to the piston rod 2 a of the shock absorber 2. The metal outer cylinder 14 fitted in the hollow portion 5T (corresponding to the fitting hole) of the holder 5 of the air suspension device 1, and the inner and outer cylinders 12, 14 are interposed between the inner cylinder 12 and the outer cylinder 14. And a main body rubber portion 16 (corresponding to a rubber-like elastic body).

  Then, the lower stopper rubber portion 24B with respect to the lower stopper receiving portion 5b on the vehicle body side disposed at a distance from the lower side of the inner cylinder 12 (one outer side in the axial direction J) is disposed in the axial direction of the inner cylinder 12. The upper stopper rubber portion 24A is attached to one end portion (lower end portion) of J and the upper stopper rubber portion 24A with respect to the upper stopper receiving portion 5a on the vehicle body side disposed at an interval above the inner cylinder 12 (on the other outer side in the axial direction J). It is attached to the other end portion (upper end portion) of the cylinder 12 in the axial direction J.

As shown in FIGS. 1 to 4, the inner cylinder 12 includes a flange 18 that is located at both ends in the axial direction and spreads outward in the radial direction, and a body portion 20 that is located between the flanges 18. The flange 18 includes a first flange portion having a constant diameter with a first side surface 18m along the axial direction J in a longitudinal section, and a second side surface 18a having an inclined curved surface inclined so as to have a smaller diameter toward the inner side in the axial direction. And a second flange portion.
Further, an end face of the flange 18 in the axial direction J (that is, an outer side face away from the center of the flange 18 in the axial direction J) 18b is an end face of the inner cylinder 12 in the axial direction J. It is configured in a vertical plane.
The trunk portion 20 is smaller in diameter than the flange 18 and has a constant outer diameter in the axial direction J, and has a through hole 18c inserted into the piston rod 2a of the shock absorber 2 therein.

  The outer cylinder 14 is longer than the inner cylinder 12 in the axial direction J, is formed in a cylindrical shape having a substantially constant inner diameter and outer diameter, and the two-stage O-ring 4 is mounted on the outer peripheral surface of the lower end portion. The concave groove 22 is provided. The outer cylinder 14 having such a cylindrical structure is fitted in the hollow portion 5T of the cylindrical holder 5 in a state where the O-ring 4 is mounted in the concave groove 22.

  As shown in FIGS. 1 and 6, the main body rubber portion 16 is vulcanized and bonded to the outer peripheral surface 20A of the body portion 20 of the inner cylinder 12 and the inner peripheral surface 14A of the outer cylinder 14 facing the outer peripheral surface 20A. Has been combined.

  As shown in FIGS. 2 and 3, the upper and lower stopper rubber portions 24A for restricting the displacement in the axial direction J of the inner cylinder 12 are formed on the upper and lower end surfaces 18b as both ends in the axial direction J of the flange 18, as described above. , 24B are attached. The upper and lower stopper rubber portions 24 </ b> A and 24 </ b> B are fitted on the flange 18 so as to protrude outward in the axial direction from the end surface 18 b of the flange 18, and are formed in a ring shape over the entire circumference of the flange 18.

  A plurality of protrusions 26 protruding in the axial direction are provided on the tip surfaces (axially outer surfaces) of the upper and lower stopper rubber portions 24A and 24B. The tip of the protrusion 26 has a hemispherical shape, and as shown in FIGS. 2 and 3, four are provided in the circumferential direction in this embodiment. The upper and lower stopper rubber portions 24A and 24B are provided with a lower surface portion 28 located on the inner side in the axial direction from the end surface 27 in the axial direction J of the stopper rubber portions 24A and 24B around each protrusion 26.

  The space on the axially outward side of the low surface portion 28 is when one of the upper and lower stopper rubber portions 24A and 24B is pressed against one of the upper and lower stopper receiving portions 5a and 5b due to the axial displacement of the inner cylinder 12. The upper and lower stopper rubber portions 24A and 24B function as an air flow passage for communicating the space between the inner peripheral side and the outer peripheral side of the upper and lower stopper rubber portions 24A and 24B. Thereby, generation | occurrence | production of abnormal noise can be aimed at.

  A straight hole 30 concentric with the inner cylinder 12 is provided on both axial end surfaces of the main rubber part 16, and a thin attached part 16 </ b> A, which will be described later, is provided on the outer periphery of the flange 18. The attached portion 16 </ b> A is formed of a thin rubber-like elastic body that is continuous with the main body rubber portion 16, and is formed integrally with the main body rubber portion 16. Reference numeral 34 denotes an annular space that surrounds the outer periphery of the attached portion 16A. The straight hole 30 is provided over the entire circumference of the inner cylinder 12.

  Next, the attachment structure between the upper and lower stopper rubber portions 24A and 24B and the main rubber portion 16 will be described by taking the attachment structure between the upper stopper rubber portion 24A and the main rubber portion 16 as an example. The attachment structure of the lower stopper rubber portion 24B and the main rubber portion 16 is the same as the attachment structure of the upper stopper rubber portion 24A and the main rubber portion 16.

The upper stopper rubber portion 24A and the main rubber portion 16 are manufactured as separate parts in the manufacturing process.
As shown in FIG. 3, in the lower end portion having the downward opening 24a, an annular first protrusion 24b (corresponding to the engaging portion) protruding inward (radially inward) protrudes from the edge of the downward opening 24a. It is formed. As shown in FIG. 5, with respect to the cross-sectional shape of the first protrusion 24b, the inner edge in the axial direction is formed on a flat surface 24e parallel to a line orthogonal to the axis. Further, the outer edge in the axial direction is formed on an inclined surface 24f that spreads downward and becomes larger in diameter toward the outer side in the axial direction. By forming the inclined surface 24f in this way, when the lower stopper rubber portion 24B is covered with the flange 18 (“when fitted”, the same applies hereinafter), the inclined surface 24f is easily covered as a guide surface. can do.

  As shown in FIG. 4, on the flange 18 side, an annular second protrusion 16a having a semicircular arc cross section is formed outward (radially outward) from the outer peripheral surface of the attached portion 16A (on the engaged portion). Equivalent).

  With the above configuration, when the upper and lower stopper rubber portions 24A and 24B are externally fitted to the flange 18, the first protrusion 24b of the stopper rubber portion 24A gets over the second protrusion 16a of the attached portion 16A and the inner side of the second protrusion 16a ( The first protrusion 24b and the second protrusion 16a engage with each other in the retaining direction, and the mounting state of the upper and lower stopper rubber portions 24A and 24B is fixed. The first protrusion 24b is referred to as an engaging part, and the second protrusion 16a is referred to as an engaged part. An engaging mechanism B is constituted by the engaging portion and the engaged portion.

As described above, the use of the engagement mechanism B to connect the upper and lower stopper rubber portions 24A and 24B and the main rubber portion 16 has the following effects.
That is, the upper and lower stopper rubber portions 24A and 24B are attached and fixed using the engaging mechanism B as means for attaching and fixing the upper and lower stopper rubber portions 24A and 24B to the flange 18 of the inner cylinder 12 of the vibration isolating bush A. The combined state is not easily released, and the retaining effect by the engagement mechanism B can be obtained.
Accordingly, when the vibration isolating bush A in a state where the stopper rubber portions 24A and 24B are attached to the end portions in the axial direction J of the inner cylinder 12 is transported, the stopper rubber portions 24A and 24B are dropped from the inner cylinder 12. It can be avoided.
Moreover, the process of applying an adhesive is not necessary, and the manufacturing process can be simplified.
And when the 1st protrusion 24b engages with the 2nd protrusion 16a, an operator can grasp | ascertain sensuously that the mounting state was completed from the place where engagement resistance can be felt to an operator.
Therefore, the mounting state of the upper and lower stopper rubber portions 24A and 24B is stable as compared with the mounting by bonding, and the manufacturing process can be simplified and the reliability of work can be ensured.

Further, the first protrusion 24b is a protrusion provided on the stopper rubber portions 24A and 24B, and the second protrusion 16a is a protrusion provided on an end portion in the axial direction J of the inner cylinder 12, so that There are the following effects.
That is, since both the first protrusion 24b and the second protrusion 16a are formed by protrusions, even when the shapes of the protrusions or the like lack precision when engaging both, the first protrusion 24b and the second protrusion 16a are engaged with each other over the other. Since it exhibits a retaining function, it is not necessary to strictly control the dimensions of the protrusions.
Therefore, it has been possible to provide a structure having a small engagement burden such as dimensional management while having a strong engagement structure.

  As shown in FIGS. 3 and 5, the mounting space a to the flange 18 positioned above the space surrounded by the first protrusion 24b of the upper stopper rubber portion 24A, the outer surface portion on which the protrusion 26 is formed, An annular space b along the mounting space a is formed in the wall thickness between the two. With this structure, when the upper stopper rubber portion 24A is externally fitted to the flange 18, the back wall 24c of the mounting space a is pressed against the one end face 18b in the axial direction J of the flange 18 so that the back wall 24c becomes the space b. When the concave portion is recessed toward the surface, the space b is deformed, and the back wall 24c and the one end face 18b are strongly pressed to exert an elastic holding function, so that the upper stopper rubber portion 24A is attached to the flange 18 The state (attached state) can be stabilized.

When manufacturing the anti-vibration bush A, the inner cylinder 12 and the outer cylinder 14 are set in a mold (not shown), a rubber compound is injected into the cavity, and the main rubber portion 16 is vulcanized. .
Then, drawing is performed after vulcanization and the outer diameter of the outer cylinder 14 is reduced, so that the main rubber portion 16 is pre-compressed to provide durability.
Next, the outer cylinder 14 is cut to form a concave groove 22 for mounting an O-ring. As a result, the vibration isolating bush A is obtained.

[Another embodiment]
(1) Concerning another embodiment of the attachment structure of the upper and lower stopper rubber portions 24A, 24B to the flange 18 of the inner cylinder 12, the attachment structure of the lower stopper rubber portion 24B is taken as an example contrary to the first embodiment. I will explain. The attachment structure of the upper stopper rubber portion 24A is the same as the attachment structure of the lower stopper rubber portion 24B.

As shown in FIGS. 8 and 9, an annular first protrusion 24 b that protrudes inwardly protrudes from an edge 24 a of the upward opening at the lower end portion of the lower stopper rubber portion 24 </ b> B.
On the other hand, in the flange 18 on the side where the lower stopper rubber portion 24B is externally fitted, the mating side that engages with the first protrusion 24b is the first side surface 18m of the flange 18 (in the longitudinal section of the inner cylinder 12). The first side surface 18m) along the axial direction J is an engagement target.

  With the above configuration, in a state where the lower stopper rubber portion 24B is externally fitted to the flange 18 of the inner cylinder 12 (see FIG. 9), the tip of the first protrusion 24b of the lower stopper rubber portion 24B is By engaging the first side surface 18 m of the flange 18, the attachment state to the flange 18 can be maintained. In FIG. 9, the shape of the first protrusion 24b before compression is indicated by a broken line (the first protrusion 24b is compressed in the above-described external fitting state).

  As described above, the engaging portion is the first protrusion 24b provided on the stopper rubber portion 24B, and the engaged portion is the first side surface 18m of the flange 18 in the inner cylinder 12, so that the following operation is performed. There is an effect. That is, since the first side surface 18m can be used as the engaged portion, it is not necessary to newly form the engaged portion, and the first side surface 18m can be used as the engaged portion.

Longitudinal section showing anti-vibration bush Top view of stopper rubber Exploded longitudinal sectional view showing the state before the upper and lower stopper rubber parts are attached to the inner cylinder etc. FIG. 3 is a partially enlarged longitudinal sectional view showing the attached portion in FIG. FIG. 3 is a partially enlarged longitudinal sectional view showing the engaging portion in FIG. Longitudinal section showing the air suspension device Longitudinal section showing a conventional anti-vibration bush An exploded longitudinal sectional view showing another embodiment of the engagement mechanism and showing a state before the lower stopper rubber portion is attached to the inner cylinder or the like The longitudinal cross-sectional view which shows another embodiment of an engagement mechanism, and shows the state after attaching the lower stopper rubber part to an inner cylinder etc.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air suspension apparatus 2 Shock absorber 2a Piston rod 3 Outer shell 3A Upper end surface 3B of outer shell Lower shell 4 O-ring 5 Holder 5T Hollow part (fitting hole)
5a Upper stopper receiving part (stopper receiving part)
5b Lower stopper receiving part (stopper receiving part)
6 Nut 7 Air chamber 9 Car body 12 Inner cylinder 14 Outer cylinder 14A Inner peripheral surface 16 of outer cylinder Main body rubber part (rubber-like elastic body)
16a 2nd protrusion (engaged part)
16A Attached part 18 Flange (Axial end of the inner cylinder)
18a 2nd side surface 18b End surface 18c of the axial direction of a flange Through-hole 18m 1st side surface (engaged part)
20 trunk part 20A outer peripheral surface 22 of trunk part concave groove 24A upper stopper rubber part (stopper rubber part)
24a downward opening 24b first protrusion (engagement portion)
24c Back wall 24e Flat surface 24f Inclined surface 24B Lower stopper rubber part (stopper rubber part)
26 Protrusion 27 End surface 28 Low surface portion 30 Straight hole 34 Space portion A Anti-vibration bush a Mounting space b Annular space B Engagement mechanism J Axial direction

Claims (3)

An inner cylinder that is extrapolated and fixed to the piston rod of the shock absorber;
An outer cylinder fitted in the fitting hole on the vehicle body side;
A rubber-like elastic body that connects the inner and outer cylinders,
Anti-vibration bushes attached to both end portions of the inner cylinder in the axial direction with stopper rubber portions for the stopper receiving portions on the vehicle body side arranged on both outer sides in the axial direction of the inner cylinder,
An anti-vibration bushing in which the stopper rubber portion is attached to an end portion in the axial direction of the inner cylinder via an engagement mechanism including an engagement portion and an engaged portion.   The anti-vibration bushing according to claim 1, wherein the engaging portion is a protrusion provided on the stopper rubber portion, and the engaged portion is a protrusion provided on an end portion in an axial direction of the inner cylinder.   The vibration isolating bush according to claim 1, wherein the engaging portion is a protrusion provided on the stopper rubber portion, and the engaged portion is a side surface of an end portion in an axial direction of the inner cylinder.

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