JPH053670U - Sliding rubber bush - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] In a sliding type rubber bush that is rotatable with respect to a support shaft and is slidable in the axial direction, between the dust boot and the rubber bush that seals the sliding part. To ensure that the [Structure] On the outer peripheral surface of the inner cylinder 26, a rubber-like elastic body mounting portion 38 is provided at a position corresponding to the rubber-like elastic body 28, and an inner cylinder 26 is formed adjacent to both axial end portions of the rubber-like elastic body mounting portion 38. A boot mounting portion 35 to which the one-end large opening portion 36 of the dust boot for sealing the sliding portion with the support shaft is mounted is formed, and an end portion in the axial direction of the rubber-like elastic body mounting portion 38 of the inner cylinder 26 is formed. The radial height H is larger than the radial height h of the one end large opening 36 of the dust boot mounted on the boot mounting portion 35.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rubber bush used for a suspension of an automobile and the like, and more particularly to a slide type rubber bush which is rotatable with respect to a support shaft and slidable in an axial direction.

[0002]

[Prior Art]

 In an automobile suspension, a rubber bush is often used in a link or an arm connecting portion arranged between a wheel and a vehicle body in order to absorb vibration transmitted from the wheel to the vehicle body. Generally, the rubber bush is composed of an inner cylinder and an outer cylinder which are arranged concentrically with a space therebetween, and a rubber-like elastic body which is mounted between the inner and outer cylinders. The rubber-like elastic body is vulcanized and adhered to the inner cylinder and the outer cylinder, respectively. Then, the inner cylinder is fitted and supported by a support shaft attached to the vehicle body or the wheel side, and the outer cylinder is fixed to the other side. When such a rubber bush is used for a suspension, its inner cylinder is usually fixed to the support shaft. By doing so, when the wheel is displaced with respect to the vehicle body, the inner and outer cylinders of the rubber bush are relatively displaced in the radial direction, the circumferential direction, or the axial direction, and the rubber-like elastic body is caused by the relative displacement. Since it is elastically deformed, vibrations in various directions are absorbed by the elasticity.

By the way, there is a vehicle rear suspension in which the posture of the wheels during bump prebound is controlled by one trailing arm and three lateral links, which is disclosed in Japanese Patent Laid-Open No. 62-6806. As disclosed in, a rear suspension is proposed in which the front end side of the trailing arm extends forward of the vehicle body-side connecting portion and one of the three lateral links is connected to the extension portion. Has been done. In such a suspension, the longitudinal impact force applied to the wheels is transmitted to the vehicle body via the trailing arm. Therefore, in order to absorb the impact force and improve the compliance, a rubber bush is used at the vehicle body connecting part of the trailing arm.

In the case of the suspension as described above, it is desirable that the rubber bush used for the vehicle body side connecting portion of the trailing arm be rotatable with respect to the supporting side and slidable in the axial direction. Be done. As such a sliding type rubber bush, there is one as disclosed in Japanese Utility Model Laid-Open No. 63-188348. In the rubber bush, the inner cylinder is a sliding sleeve made of a material having a small coefficient of friction, and the sliding sleeve is fitted and supported by the support shaft. If such a sliding rubber bush is used, the lateral displacement of the trailing arm in the vehicle body can be allowed without any resistance, so that the lateral link can smoothly control the posture of the wheel. Further, even when the trailing arm swings up and down, the inner cylinder of the rubber bush may rotate with respect to the support shaft, and an unnecessary load may be applied to the rubber-like elastic body between the inner cylinder and the outer cylinder. Since it disappears, the durability of the rubber bush is improved.

By the way, when making the inner cylinder of the rubber bush slidable with respect to the support shaft in this way, water, dust, and the like enter the sliding portion between the inner cylinder and the support shaft. It is necessary to prevent the sliding resistance from increasing. Therefore, in the one disclosed in the above publication, one end of the main part of the rubber bush 105 is connected to the rubber bush 105 as shown in FIG. 4, and the other end (not shown) is closely fixed to the outer peripheral surface of the support shaft 132. Is provided, and the sliding portion is sealed from the outside. Since the dust boots 132 are detachably mounted on the inner cylinder 126 of the rubber bush 105, boot mounting portions 135 are formed at both axial end portions of the outer peripheral surface of the inner cylinder 126, and the boot mounting portions 135 have dust boots. A large opening 136 at one end of 132 is fastened and fixed by a circlip or the like.

[0006]

[Problems to be solved by the device]

 However, when such a slide type rubber bush is used for the trailing arm of the suspension as described above, the rubber bush is displaced relative to the support shaft both in the radial direction and the axial direction, and therefore, Torsional and tensile forces act on the dust boot 132. Therefore, only by fixing one end of the dust boot 132 with the circlip 134 or the like, it is inevitable that the end edge portion of the one end opening 136 of the dust boot 132 is deformed.

In particular, when the rubber bush 105 is displaced in the radial direction relative to the support shaft, as shown in FIG. 4, the rubber-like elastic body 128 that is strongly pressed in the displacement direction is the outer cylinder 127. A bulged portion 129 that is compressed between the inner cylinder 126 and is bent outside is formed at both ends in the axial direction that are not restrained. Therefore, the bulging portion 129 of the bent rubber-like elastic body 128 interferes with the end of the one end opening 136 of the dust boot 132 attached to the boot mounting portion 135 of the inner cylinder 126, and the bulging portion 129 In order to press in the bending direction, that is, both ends in the axial direction of the support shaft, even if the one end opening 136 of the dust boot 132 is brought into close contact with the boot mounting portion 135 of the inner cylinder 126, the above-mentioned pressing force is not applied. As a result of repetition, a gap S is generated as shown in FIG. 5, which is an enlarged view of the same portion of FIG. 4A.

When the gap S is thus formed between the dust boot 132 and the boot mounting portion 135, water or the like enters from the portion and adheres to the boot mounting portion 135. Since the rubber bush inner cylinder 126 is generally made of an iron thread material, if water or the like adheres to the boot bush mounting portion 135, rust occurs. In order to prevent the occurrence of such rust, it is conceivable to subject the inner cylinder 126 to anticorrosion treatment. However, if the entire inner cylinder 126 is subjected to antirust treatment, the inner cylinder 126 will have a rubber-like bullet. The physical body 128 cannot be bonded. Although it is sufficient to apply the rustproofing treatment only to the boot mounting portion 135 of the inner cylinder 126, if this is done, the rustproofing treatment will take time and productivity will be reduced. In particular, after the dust boot is assembled, the boot mounting portion 135 is covered with the dust boot 132, so that the boot mounting portion 135 of the inner cylinder 126 cannot be rust-proofed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to ensure that the dust boot and the rubber bush are reliably sealed in the sliding rubber bush as described above. It is to be.

[0010]

[Means for Solving the Problems]

 The present invention has the following configuration.

On the outer peripheral surface of the inner cylinder, the rubber-like elastic body mounting portion is provided at a position corresponding to the rubber-like elastic body, and both ends of the rubber-like elastic mounting portion in the axial direction are adjacent to each other. One end of the dust boot that seals the sliding part between the two boots is formed with a large opening, and the radial height of the axial end of the rubber-like elastic body mounting part of the inner cylinder is formed. The height is set larger than the radial height of the large opening at one end of the dust boot attached to the boot mounting portion.

[0012]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a slide type rubber bush 5 according to the present invention. FIG. 1 is a longitudinal sectional view thereof, and FIG. 2 shows that the rubber bush 5 moves in a radial direction relative to a support shaft 7. It is explanatory drawing which expands and shows the principal part at the time of doing.

The rubber bush 5 is arranged between an inner cylinder 26, an outer cylinder 27 arranged concentrically on the outer peripheral side of the inner cylinder 26 with a space therebetween, and between the inner cylinder 26 and the outer cylinder 27. And a rubber-like elastic body 28. The rubber-like elastic body 28 is a ring-shaped one having a space 29 on both sides in the diametrical direction, and its inner peripheral surface and outer peripheral surface are vulcanized and adhered to the inner cylinder 26 and the outer cylinder 27, respectively, thereby making them inner and outer cylinders. 26 and 27 are connected to each other. The rubber bush 5 is fixed to the trailing arm by press-fitting the outer cylinder 27 thereof into an opening provided in a vehicle body side connection portion of a training arm (not shown).

A sliding collar 30 made of a material having a small friction coefficient is mounted on the inner peripheral surface of the inner cylinder 26 of the rubber bush 5. The collar 30 is fitted on the outer circumference of the support shaft 7 fixed to the vehicle body side. The support shaft 7 is made sufficiently longer than the inner cylinder 26. In this way, the rubber bush 5 is configured such that the inner cylinder 26 thereof can slide in the axial direction and the rotation direction with respect to the support shaft 7. That is, the rubber bush 5 is a slide type rubber bush.

A rubber-like elastic body mounting portion 38 is formed on the outer peripheral surface of the inner cylinder 26 of the rubber bush 5 at a position corresponding to the rubber-like elastic body 28, and the inner cylinder 26 is mounted with the rubber-like elastic body. It is adapted to extend outward in the axial direction from the portion 38. Further, cylindrical dust boots 32, 32 made of an airtight and flexible material such as thin rubber are arranged between the extending portion and both ends of the support shaft 7. The one end large openings 36, 36 of the dust boots 32, 32 are press-fitted into the outer circumference of the end of the inner cylinder 26 and fixed at a position where they abut the axial ends 31, 31 of the rubber-like elastic body mounting portion 38. It has become so . The dust boots 32, 32 have large openings 36, 36 at one end by fitting and tightening a circlip 34 on the outer circumference of the inner cylinder 26 adjacent to both ends 31, 31 in the axial direction of the rubber-like elastic body mounting portion 38. It is locked and fixed in a state where movement in the axial direction is restricted. That is, both ends in the axial direction of the outer peripheral surface of the inner cylinder 26 are boots mounting portions 35, 35.

The axial end portions 31, 31 of the rubber-like elastic body mounting portion 38 are formed, for example, in the shape of protrusions, and the radial heights H of the axial end portions 31 are adjacent to each other as shown in FIG. The dust boot 32 mounted on the boot mounting portion 35 of the cylinder 26 is larger than the radial height h of the one-end large opening 36.

Next, the operation of the slide type rubber bush 5 thus configured will be described.

When the slide type rubber bush 5 attached to the suspension arm or the like is displaced relative to the support shaft 7 in the radial direction as shown in FIG. 1, it is strongly pressed in the displacement direction as shown in FIG. The rubber-like elastic body 28 is compressed between the outer cylinder 27 and the inner cylinder 26 and flexes outward at both axial ends which are not restrained and bulges into a free shape.

However, in the case of the rubber bush 5 of the present invention, the radial height H of the axial end 31 of the rubber-like elastic body mounting portion 38 provided on the outer peripheral surface of the inner cylinder 26 is equal to that of the boot mounting. Since the dust boot 32 mounted on the portion 35 is larger than the radial height h of the large opening 36 at one end of the dust boot 32, even when the compressed rubber-like elastic body 28 swells as described above, The bulging portion 29 comes into contact with the tip of the axial end 31 of the rubber-like elastic body mounting portion 38, but does not interfere with the one end opening 36 of the dust boot 32. Therefore, due to the damming action of the axial end portion 31, there is no gap between the outer peripheral surface of the boot attachment portion 35 and the one end large opening portion 36 of the dust boot 32, and there is no fluid tightness. The sealed state is maintained.

Further, as shown in FIG. 1, the other ends of the dust boots 32, 32 are sealed to the outer peripheral surface of the support shaft 7. That is, both ends of the dust boots 32, 32 are sealed to the rubber bush 5 and the support shaft 7, respectively, and the sliding portions between the inner cylinder 26 and the support shaft 7 are externally sealed by the dust boots 32, 32. It is hermetically sealed to prevent water and the like from entering the dust boots 32, 32. Therefore, rust is not generated on the boot mounting portions 35, 35 of the inner cylinder 26, so that it is not necessary to apply rustproofing treatment to the inner cylinder 26, and the increase in manufacturing cost can be suppressed.

In the above embodiment, one end of the dust boot 32 is fixed to the inner cylinder 26 of the rubber bush 5 as it is, but as shown in FIG. 3B, a material having corrosion resistance such as stainless steel. The fastening force may be strengthened by attaching the attachment ring 33 formed by the above to the large opening 36 at one end of the boot 32 in advance and then fixing it to the boot attachment portion 35.

Further, the end of the rubber-like elastic body mounting portion 38 in the axial direction 31 and the end of the dust boot 32 mounted on the boot mounting portion 35 corresponding to the height difference (H-h) of the large opening portion 36 are the ends. Since the outer peripheral surface of the portion 31 is exposed, as shown in FIG. 3B, an extension portion extending to the boot attachment portion 35 at both axial end portions of the inner peripheral portion of the rubber-like elastic body 28. 37 is provided so that the dust boot 32 can be sandwiched between the large opening 36 at one end of the dust boot 32 and the boot mounting portion 35 of the inner cylinder 26 to prevent water or the like from adhering to the bare portion. Is more desirable.

Further, the present invention is not limited to the rubber bush 5 used for the suspension of the automobile as in the above-described embodiment, but can be similarly applied to the rubber bush having other structures.

[0025]

[Effect of the device]

 As described above, according to the present invention, even when the sliding rubber bush is radially displaced relative to the support shaft and the rubber-like elastic body is compressed and flexed and bulges toward the free end in the axial direction, The radial height of both ends in the axial direction of the rubber-like elastic body provided on the outer peripheral surface of the cylinder is set larger than the radial height of the one end large opening of the dust boot attached to the boot mounting portion. Therefore, the expanded portion of the compressed rubber-like elastic body does not interfere with the large opening of the dust boot at one end. Therefore, there is no gap between the outer peripheral surface of the boot mounting portion and the one large opening of the dust boot, and the fluid-tight sealed state is maintained.

Therefore, it is possible to prevent water, dust, and the like from entering the inside of the dust boot, and to prevent rust due to the water and the like adhering to the inner boot mounting portion.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional plan view showing an embodiment of a sliding rubber bush according to the present invention.

FIG. 2 is a cross-sectional plan view showing a main part when the sliding rubber bush of FIG. 1 is displaced relative to a support shaft in a radial direction.

3A and 3B are cross-sectional plan views showing a main part of a slide type rubber bush according to another embodiment of the present invention.

FIG. 4 is a sectional plan view showing a main part of a conventional slide type bush.

5 is an enlarged cross-sectional plan view showing the same portion as portion A in FIG.

[Explanation of symbols]

 5 Sliding Rubber Bushing 7 Support Shaft 26 Inner Cylinder 27 Outer Cylinder 28 Rubber Elastic Body 31 Axial End 35 Boot Mounting Part 36 Boot One End Large Opening 38 Rubber Elastic Body Mounting Part H Rubber Elastic Body Mounting Part End Radial height of boot h Radial height of large opening at one end of boot

Claims (1)

[Claims for utility model registration] 1. An inner cylinder (26) fitted to the outer periphery of a support shaft (7) so as to be rotatable and slidable in the axial direction, and the inner cylinder (26). An outer cylinder (27) which is concentrically arranged on the outer peripheral side of the core and a rubber-like elastic body (28) which is arranged between the inner cylinder (26) and the outer cylinder (27). In the rubber bush, the rubber-like elastic body mounting portion (38) is provided on the outer peripheral surface of the inner cylinder (26) at a position corresponding to the rubber-like elastic body (28), and the rubber-like elastic body mounting portion (38). Adjacent to both axial end portions (31), (31), one end of the dust boots (32), (32) that seals the sliding portion between the inner cylinder (26) and the support shaft (7) is large. Opening (36),
Boot attachment parts (35), (35) to which (36) is attached
And the radial height (H) of the axial end portions (31) and (31) of the rubber-like elastic body mounting portion (38) of the inner cylinder (26) is the same as the boot mounting portion ( 35), (3
Slides characterized by being provided larger than the radial height (h) of the one-end large openings (36), (36) of the dust boots (32), (32) mounted in 5). Type rubber bush.