JPH068835U - bush - Google Patents

Abstract

(57) [Summary] [Purpose] To secure the dimensional accuracy and strength of an inner cylinder member having a specific outer peripheral surface shape. [Structure] The outer cylinder member 1 has tapered squeezing portions 11 on both ends in the axial direction, the diameter of which becomes smaller toward the tip. The inner tubular member 2 disposed inside the outer tubular member 1 is a straight tubular tubular portion 2.
1, and first and second resin blocks integrally formed at opposite ends centering on the cylinder axis O on both axial ends thereof and having tip inclined surfaces 22a and 23a extending in proximity to the narrowed portion 11. It is composed of bodies 22 and 23. A rubber elastic body 3 which is interposed between the outer tubular member 1 and the inner tubular member 2 and integrally connects the two.
The hollow portion 3a is formed at both ends in the axial direction at opposite positions centering on the cylinder axis O and in the circumferential portion where the resin block bodies 22 and 23 are not arranged.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bush suitable for use in a link type suspension bush of a vehicle.

[0002]

[Prior art]

 BACKGROUND ART Conventionally, as a bush used for a suspension mechanism that supports a wheel of an automobile, one disclosed in JP-A-60-157531 is known. As shown in FIG. 9 and FIG. 10, this bush has an outer cylinder member 5 having tapered narrowed portions 51 whose diameters become smaller toward both ends in the axial direction, and the inside of the outer cylinder member 5, respectively. An inner cylinder member 6 which is formed by bulging and has a bulge portion 61 which is disposed radially outward and bulges radially outward and has a tapered surface 6a extending opposite the narrowed portion 51. It is interposed between the outer tubular member 5 and the inner tubular member 6 to integrally connect the two, and has a pair of hollow portions 7a formed at opposite ends about the tubular axis O on both axial ends thereof. It is composed of a rubber elastic body 7.

In the conventional bush having the above-mentioned configuration, the outer cylinder member 5 is press-fitted into a suspension link or the like, and the shaft portion of a fastening bolt such as a vehicle body is fixed in the inner cylinder member 6 for use. . Then, the structure is configured to receive the prying load in the direction of arrow P in FIG. 9 acting between the outer tubular member 5 and the inner tubular member 6 by the compression / pulling of the rubber elastic body 7 arranged in the arrow P direction. ing.

[0004]

[Problems to be solved by the device]

 By the way, in the above-mentioned conventional bush, a high technique is required to form the bulge portion 61 of the inner tubular member 6 by bulging, and it is difficult to perform the dimensional accuracy with high precision. Further, since the straight tubular metal tubular member is plastically deformed by bulging, there is a problem that the deformed portion becomes weak in strength.

The present invention has been made in view of the above circumstances, and in a bush having a structure in which a rubber elastic body interposed between the inner and outer cylindrical members receives a prying load between the inner and outer cylindrical members, the bush has a specific outer peripheral surface shape. Ensuring the dimensional accuracy and strength of the tubular member is a technical issue to be solved.

[0006]

[Means for Solving the Problems]

 The bush of the present invention has outer cylindrical members each having a tapered narrowed portion that becomes smaller in diameter toward both ends in the axial direction, and a straight tubular member disposed inside the outer cylindrical member. A first resin block body integrally formed on a part of an outer peripheral surface of the tubular portion on one axial side of the tubular portion and having a tip inclined surface extending in proximity to the throttle portion on the one end side; The first resin block body is integrally formed with a part of the outer peripheral surface of the tubular portion on the other end side in the axial direction of the tubular portion at an opposite position with the tubular axis of the tubular portion as a center, and the diaphragm on the other end side is formed. An inner cylinder member made of a second resin block body having a tip end inclined surface extending close to the portion, and interposed between the outer cylinder member and the inner cylinder member to integrally connect the two. At both ends in the axial direction at opposite positions around the cylinder axis and in the circumferential direction where the resin block body is not arranged. It characterized in that it consists of a rubber elastic body hollow portion of the pair is formed.

[0007]

[Action]

 In the bush of the present invention, the inner tubular member is composed of a straight tubular portion and a pair of resin block bodies arranged at predetermined positions on both axial ends of the tubular portion. This resin block body can be made to have a predetermined external shape, size, forming position, etc. easily and highly accurately by injection molding or the like. Therefore, the inner cylindrical member of the bush of the present invention can be easily processed and high dimensional accuracy can be secured.

[0008] Further, since the tubular portion forming the inner tubular member is not subjected to bulging as in the conventional case, the strength is secured.

[0009]

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. (Embodiment 1) The bush of this embodiment shown in the axial cross-sectional view of FIG. 1 is composed of a metal outer cylinder member 1 and a metal straight tubular cylinder arranged concentrically inside the outer cylinder member 1. The inner cylinder member 2 including the portion 21 and the pair of resin block bodies 22 and 23 fixed to the outer peripheral surfaces on both axial ends of the cylinder portion 21, and interposed between the outer cylinder member 1 and the inner cylinder member 2. It is composed of a rubber elastic body 3 which integrally connects the both. 2 is a sectional view taken along the line AA of FIG.

On both axial ends of the outer tubular member 1, tapered narrowed portions 11 each having a diameter smaller toward the tip are formed. The cylindrical portion 21 constituting the inner cylindrical member 2 has a step portion 21a formed on the outer peripheral surface thereof by cutting or forging. The step portion 21a has a first resin block body 22 and a second resin block body 23. And the resin thin portion 24 are integrally formed and fixed by injection molding. By forming the step portion 21a on the outer peripheral surface of the tubular portion 21 and forming the resin block bodies 22 and 23 in the step portion 21a, the axial direction between the tubular portion 21 and the resin block bodies 22 and 23 is formed. Can effectively regulate the relative movement of the. Further, by forming the resin thin portion 24 integrally with each of the resin block bodies 22 and 23, the joint area between the resin portion and the tubular portion 21 can be increased, and the joint strength between both can be increased. One of the first resin block bodies 22 is integrally formed on a part of the outer peripheral surface of the tubular portion 21 at one end side in the axial direction of the tubular portion 21, and extends toward the narrowed portion 11 at the one end side so as to extend toward the tip and be inclined. It has a surface 22a. On the other hand, the other second resin block body 23 is located at a position opposite to the first resin block body 22 and the cylinder axis O of the cylinder portion 21 on a part of the outer peripheral surface of the cylinder portion 21 on the other axial end side of the cylinder portion 21. Has a tip inclined surface 23a which is formed integrally with the other end and extends so as to closely face the narrowed portion 11 on the other end side. Each of the resin block bodies 22, 23 extends from the vicinity of one axial end of the tubular portion 21 to a position slightly beyond the axial center C of the tubular portion 21. Then, the end inclined surfaces 22b and 23b are formed on the terminal sides of the resin block bodies 22 and 23, respectively. When the minimum diameter of the throttle portion 11 of the outer cylinder member 1 is D, the height h of each of the resin block bodies 22 and 23 from the cylinder axis O is set to be larger than D / 2.

The rubber elastic body 3 is fixed to the inner peripheral surface of the outer cylindrical member 1 and the outer peripheral surface of the inner cylindrical member 2 by vulcanization adhesion. The rubber elastic body 3 is formed with a pair of hollow portions 3a at opposite ends with respect to the cylinder axis O on both axial sides and at circumferential positions where the resin block bodies 22 and 23 are not arranged. . The hollow portion 3a has an arc-shaped cross-section in the direction perpendicular to the axis, is formed along the vicinity of the inner peripheral surface of the outer tubular member 1, and extends slightly from the axial end to the axial center C of the tubular portion 21. It extends to the beyond position.

The bush of this embodiment can be manufactured as follows. First, the resin block bodies 22, 23 and the resin thin portion 24 are formed by injection molding at predetermined positions on the outer peripheral surface of the tubular portion 21 formed by cutting the stepped portion 21 a to form the inner tubular member 2. The inner tube member 2 and the straight tube-shaped outer tube member 1 in which the narrowed portion 11 is not formed are placed in a predetermined vulcanization mold, and the rubber elastic body 3 is vulcanized and molded into a predetermined shape. The member 1 and the inner cylinder member 2 and the rubber elastic body 3 are vulcanized and bonded. Then, the drawn portions 11 are formed on both axial ends of the outer tubular member 1 by drawing deformation processing, and the bush of this embodiment is completed.

In the bush of the present embodiment having the above-described configuration, the outer cylinder member 1 is press-fitted into a suspension link or the like, and the shaft portion of a fastening bolt such as a vehicle body is fixed in the inner cylinder member 2 for use. It Then, the prying load in the arrow P direction in FIG. 1 acting between the outer cylinder member 1 and the inner cylinder member 2 is applied to the rubber elastic body 3 of the portion located in the arrow P direction, that is, the throttle of the outer cylinder member 1. It can be received by the compression / pulling of the rubber elastic body 3 interposed between the portion 11 and the tip inclined surfaces 22a, 23a of the resin block bodies 22, 23 constituting the inner tubular member 2.

In the bush of this embodiment, the inner tubular member 2 includes a tubular portion 21 having a straight tubular shape, and resin block bodies 22 and 23 arranged at predetermined positions on both axial ends of the tubular portion 21. It consists of The resin block bodies 22 and 23 can be made to have a predetermined external shape, size, forming position, etc. easily and highly accurately by injection molding or the like. For this reason, the inner cylinder member 2 in the bush of this embodiment is easy to process, and high dimensional accuracy can be secured. Further, since the tubular portion 21 forming the inner tubular member 2 is not subjected to bulging as in the conventional case, the strength is secured.

(Embodiment 2) The bush of Embodiment 2 shown in FIGS. 3 and 4 is the same as the bush of Embodiment 1 except that the shape of the hollow portion 3a of the rubber elastic body 3 is changed. The structure is similar to that of the bush of the first embodiment. That is, in the bush of the second embodiment, the rubber elastic body 3 at the back of the terminal inclined surfaces 22b and 23b of the resin block bodies 22 and 23 is removed from the bush of the first embodiment, and the hollow portion 3a is perpendicular to the axis. Since the directional cross-sectional area is increased, it is possible to reduce the weight by the amount that the rubber elastic body 3 is removed as compared with the bush of the first embodiment. The other actions and effects are similar to those of the bush of the first embodiment.

(Third Embodiment) The bush of the third embodiment shown in FIGS. 5 and 6 is the same as the bush of the first embodiment except that the shapes of the resin block bodies 22 and 23 and the hollow portion 3 a of the rubber elastic body 3 are different. The formation position is changed, and other configurations are similar to those of the bush of the first embodiment. That is, the resin block bodies 22 and 23 in the bush of the third embodiment have the terminal side vertical end surfaces 22c and 23c which are vertically cut at the position of the axial center C of the tubular portion 21. The height H from the apex of the resin block bodies 22 and 23 to the resin thin portion 24 on the opposite side in the radial direction, the radial width L of the resin block bodies 22 and 23, and the minimum of the narrowed portion 11 of the outer cylinder member 1. As shown in FIG. 7, the relationship with the caliber D is such that when the inner cylinder member 2 is displaced toward the outer cylinder member 1 toward one end side in the radial direction (the side where the resin thin portion 24 is formed). , 23 are set so as to be able to pass through the narrowed portion 11 of the outer tubular member 1. In addition, the hollow portion 3a of the rubber elastic body 3 in the bush of the present embodiment is formed along the vicinity of the outer peripheral surface of the tubular portion 21 of the inner tubular member 2, and extends from the axial end to the axial center C of the tubular portion 21. It extends a little to the front.

The bush of the third embodiment can be manufactured as follows. First, the resin block bodies 22 and 23 and the resin thin portion 24 are formed in the tubular portion 21 in the same manner as in the first embodiment to form the inner tubular member 2. Then, as shown in FIG. 7, the inner cylinder member 2 is arranged on one end side in the radial direction (on the side where the thin resin portion 24 is formed) in the outer cylinder member 1 in which the narrowed portions 11 are formed at both ends in the axial direction by drawing deformation processing. While shifting, insert to the center C in the axial direction. As a result, the one first resin block body 22 passes through the narrowed portion 11 of the outer tubular member 1. After that, the inner tubular member 2 is displaced toward the other end in the radial direction with respect to the outer tubular member 1 so that the other second resin block body 23 can pass through the narrowed portion 11, and then the inner tubular member 2 is removed. Insert it completely into the outer cylinder member 1. Then, the inner cylinder member 2 and the outer cylinder member 1 are arranged in a predetermined vulcanization mold, and the rubber elastic body 3 is vulcanized and molded into a predetermined shape, and the outer cylinder member 1 and the inner cylinder member 2 The rubber elastic body 3 is vulcanized and bonded to complete the bush of this embodiment.

As described above, in the bush of the third embodiment, the narrowed portion 11 of the outer tubular member 1 can be formed before the rubber elastic body 3 is vulcanized. Therefore, as in the case where the narrowed portion 11 of the outer tubular member 1 is formed after the rubber elastic body 3 is vulcanized and molded, a large amount of strain is generated in the rubber elastic body 3 due to the drawing deformation processing, and the outer tubular member 1 and The joint strength with the rubber elastic body 3 does not decrease. Therefore, in the bush of the third embodiment, the joint strength between the outer cylinder member 1 and the rubber elastic body 3 is high, and the durability is improved. In addition, if the rust preventive agent is applied after forming the throttle portion 11 on the outer cylinder member 1 and then the rubber elastic body 3 is vulcanized and molded, it is possible to prevent the rust preventive agent from peeling off due to the squeeze deformation process. It is possible to avoid a decrease in the rust preventive power of the tubular member 1.

The other functions and effects of the bush of the third embodiment are similar to those of the first embodiment. The bush of the third embodiment can also be manufactured by the same method as in the first embodiment in which the narrowed portion 11 of the outer tubular member 1 is formed after the rubber elastic body 3 is vulcanized and molded. (Embodiment 4) The bush of Embodiment 4 shown in the axial sectional view of FIG. 8 has a height h of the resin block bodies 22 and 23 from the cylinder axis O and a minimum of the throttle portion 11 of the outer cylinder member 1. It has the same structure as the bush of the first embodiment except that the relationship with the diameter D is changed. That is, in the bush of the fourth embodiment, when the minimum diameter of the throttle portion 11 of the outer tubular member 1 is D, the height h of the resin block bodies 22 and 23 from the tubular axis O is smaller than D / 2. It is set.

Therefore, also in the bush of the fourth embodiment, like the bush of the third embodiment, after the throttle portion 11 is formed in the outer cylinder member 1, the resin block bodies 22, 23 are formed in the outer cylinder member 1. The formed inner cylinder member 2 can be easily inserted. Therefore, as compared with the manufacturing method according to the third embodiment, the workability in inserting the inner cylindrical member 2 into the outer cylindrical member 1 can be improved, and the manufacturing method according to the third embodiment can be performed. The same action and effect as in Example 3 are obtained.

[0021]

【The invention's effect】

 As described above in detail, in the bush of the present invention, the inner tubular member having a specific outer peripheral surface shape can be formed by forming the resin block body on the straight tubular tubular portion. Therefore, the outer peripheral surface shape of the inner cylinder member can be easily formed with high dimensional accuracy, and the degree of freedom in design change is high.

Further, unlike the conventional case, the bushing of the present invention has improved durability because it does not cause a decrease in strength due to bulging.

[Brief description of drawings]

FIG. 1 is an axial sectional view of a bush according to a first embodiment.

FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 according to the bush of the first embodiment.

FIG. 3 is an axial sectional view of a bush according to a second embodiment.

FIG. 4 is a cross-sectional view taken along the line AA of FIG. 3 relating to the bush of the second embodiment.

FIG. 5 is an axial sectional view of a bush according to a third embodiment.

FIG. 6 is a cross-sectional view taken along the line AA of FIG. 5 relating to the bush of the third embodiment.

FIG. 7 is a side view illustrating a state when the inner cylinder member is inserted into the outer cylinder member according to the bush of the third embodiment.

FIG. 8 is an axial sectional view of a bush according to a fourth embodiment.

FIG. 9 is an axial sectional view of a conventional bush.

FIG. 10 is a cross-sectional view taken along the line AA of FIG. 9 relating to a conventional bush.

[Explanation of symbols]

1 is an outer cylinder member, 2 is an inner cylinder member, 3 is a rubber elastic body, 11 is a throttle part, 21 is a cylinder part, 22 and 23 are resin block bodies, 2
Reference numerals 2a and 23a denote tip inclined surfaces, and 3a denotes a hollow portion.

Claims (1)

[Scope of utility model registration request] 1. An outer cylinder member having tapered narrowed portions on both ends in the axial direction, the diameter of which decreases toward the tip, and a straight tubular member arranged inside the outer cylinder member, A first resin block body integrally formed on a part of the outer peripheral surface of the tubular portion at one end side in the axial direction of the tubular portion, the first resin block body having a tip inclined surface extending in proximity to the throttle portion at the one end side; Of the first resin block body and an outer peripheral surface of the tubular portion on the other end side in the axial direction of the tubular portion at an opposite position centered on the tubular axis of the tubular portion. An inner cylinder member formed of a second resin block body having a tip end inclined surface extending in close proximity to the outer cylinder member, and the inner cylinder member and the inner cylinder member interposed therebetween to integrally connect the two members. A pair of hollow parts at opposite positions centered on the cylinder axis on both axial sides and at circumferential positions where the resin block body is not arranged. Bush, comprising the formed with the rubber elastic body.