JP2000280717A - Suspension bush and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively absorb harshness as checking a shock feeling newly produced by installing a separate stopper rubber. SOLUTION: Tubular stopper rubber 9 pressed in the peripheral surface of an inner cylinder 20 from the axial one end is housed in a nearly cylindrical recess 31a or a tubular cavity part where there is no rubber elastic body installed in the axial one end lying between an outer cylinder 10 and this inner cylinder 20. This stopper rubber 9 is formed as a deformed section wherein an outer surface form being only at one side of car longitudinal ones is bulged to the radial outside, therefore an outer surface of this deformed section abuts on an inner surface of the outer cylinder 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension bush used for a vehicle suspension and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in a vehicle, a suspension bush is interposed between a mounting member on a suspension side on which wheels are supported and a mounting member on a vehicle body. Is prevented from being transmitted to the vehicle body.

As a suspension bush as such a vibration isolator, for example, Japanese Patent Application Laid-Open No. 9-104212 discloses a suspension bush used for a torsion beam type suspension. The torsion beam type suspension is a torsion beam arranged with the vehicle width direction as the longitudinal direction, and a pair of left and right wheels which are arranged at the longitudinal ends of the torsion beam at substantially the longitudinal direction of the vehicle and the rear ends thereof are respectively supported by wheels. And a trailing arm. As shown in FIG. 12, the bush used for the torsion beam type suspension is disposed at the front end of each of the trailing arms 80 so that the axial direction thereof coincides with the vehicle width direction. And a mounting member (bracket) 81 on the vehicle body side.

That is, the suspension bush is provided concentrically inside the outer cylinder 82 with the outer cylinder 82 press-fitted into a press-fit portion 80a provided at the front end of the trailing arm 80, and is mounted on the vehicle body. It comprises an inner cylinder 83 fixed to the member 81 and a cylindrical rubber elastic body 84 interposed between the outer cylinder 82 and the inner cylinder 83 to connect them. FIG. 12 shows a horizontal cross section of the suspension bush. The upper part of FIG. 12 is the front side of the vehicle, and the lower part of FIG. 12 is the rear side of the vehicle.

[0005]

In the conventional suspension bush having the above structure, when radial vibration is generated between the outer cylinder 82 and the inner cylinder 83, the rubber elastic body 84 interposed therebetween is elastically deformed. This absorbs the vibration.
However, the conventional suspension bush described above
The cross-sectional shape of the rubber elastic body 84 is a simple cylindrical shape, and there has been no devised shape for absorbing the harshness. Here, the harshness is defined as a difference between 30 to 60 H, which is generated by a difference passing through a seam, a convex portion, or a concave portion of a road surface.
It means shocking vibration or shock sound of about z. As a countermeasure against such harshness, it is effective to increase the suspension front-back compliance, that is, to increase the flexibility (front-back flexibility) of the suspension when a force in the front-back direction is applied to the suspension.

Therefore, in order to reduce the spring constant of the bush in the longitudinal direction of the vehicle, a cylindrical hollow portion where no rubber elastic body 84 exists between the outer cylinder 82 and the inner cylinder 83 is provided at one axial end. Means for accommodating a cylindrical separate stopper rubber pressed into the outer peripheral surface of the inner cylinder from one end in the axial direction may be considered. According to such a separate stopper rubber, since the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder are not fixed, compared to the case where both are fixed and the relative movement between them is mutually restricted. The spring constant decreases. Further, when a gap is formed between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder, when the outer cylinder and the inner cylinder are relatively displaced in a direction to eliminate the gap, the rubber that is subjected to compression is Since the gap does not exist, the spring constant decreases accordingly.

Therefore, if a simple cylindrical gap is temporarily formed between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder, the stopper rubber and the outer cylinder are provided on both the front side and the rear side of the inner cylinder. Therefore, even if the outer cylinder moves relative to the inner cylinder in any direction of the front and rear of the vehicle, the spring constant is reduced by the gap, which is more effective as a measure against harshness. It is a target.

However, in this case, immediately after the outer cylinder and the inner cylinder are relatively displaced by the gap, the outer surface of the stopper rubber collides with the inner surface of the outer cylinder. There is a new problem. In particular, since there is a gap between the stopper rubber and the outer cylinder on both the front side and the rear side of the inner cylinder, the case where the outer cylinder is relatively displaced to the front side of the vehicle with respect to the inner cylinder and the rear side In both cases, the above-mentioned shock occurs, and the discomfort given to the occupant of the vehicle becomes remarkable.

The present invention has been made in view of the above circumstances, and a suspension bush capable of effectively inhaling a harshness while suppressing a newly generated shock feeling problem by providing a separate stopper rubber. It is a technical problem to be solved to provide.

[0010]

A suspension bush according to the present invention for solving the above-mentioned problems is provided so that an axial direction thereof coincides with a vehicle width direction, and a first mounting member on a suspension side and a second mounting member on a vehicle side. A bush for connecting the first and second mounting members, the outer cylinder being fixed to one of the first mounting member and the second mounting member;
A suspension bush comprising: an inner cylinder fixed to the other of the mounting member and the second mounting member; and a cylindrical rubber elastic body interposed between the outer cylinder and the inner cylinder to connect the two. In the cylindrical cavity where the rubber elastic body does not exist, provided at one end in the axial direction between the outer cylinder and the inner cylinder,
A cylindrical stopper rubber press-fitted from one end in the axial direction is housed in the outer peripheral surface of the inner cylinder, and the outer surface of only one side of the stopper rubber in the vehicle longitudinal direction is in contact with the inner surface of the outer cylinder. It is characterized by the following.

In this suspension bush, a cylindrical hollow portion having no rubber elastic body is provided at one axial end between the outer cylinder and the inner cylinder, and the outer surface of only one side in the vehicle front-rear direction is the inner surface of the outer cylinder. The stopper rubber which is in contact with the rubber elastic body and is separate from the rubber elastic body is accommodated in the hollow portion. According to such a separate stopper rubber, the vehicle is more rigid than the case where the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder are not fixed, and the relative movement between the two is restricted. The spring constant of the bush in the front-rear direction decreases. Also, between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder,
Since a gap is formed on the other side of the front and rear of the vehicle,
When the outer cylinder and the inner cylinder are relatively displaced in the direction of eliminating the gap, the rubber that is compressed does not exist by the gap, and the spring constant of the bush in the vehicle front-rear direction decreases accordingly. Therefore, the suspension bush of the present invention has high compliance before and after suspension, and can effectively absorb harshness.

On the other hand, the outer surface of the stopper rubber and the inner surface of the outer cylinder abut on one side of the front and rear of the vehicle between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder. When the inner cylinder is relatively displaced to the one side, since the outer surface of the stopper rubber and the inner surface of the outer cylinder are in contact with each other in advance, they do not collide with each other. There is no shock. If the inner cylinder is displaced relative to the outer cylinder on the other side of the front and rear of the vehicle, that is, on the side where a gap is formed between the outer surface of the stopper rubber and the inner surface of the outer cylinder, the outer surface of the stopper rubber And the inner surface of the outer cylinder collide with each other, and a shock at this time generates a sense of shock.

As described above, in the suspension bush of the present invention, the inner cylinder is displaced relative to the outer cylinder on one of the front and rear sides of the vehicle (on the side where the outer surface of the stopper rubber is in contact with the inner surface of the outer cylinder). In this case, it is possible to eliminate a sense of shock when the outer surface of the stopper rubber collides with the inner surface of the outer cylinder. Therefore, according to the suspension bush of the present invention, it is possible to effectively absorb the harshness while suppressing the problem of a newly generated shock feeling by providing the separate stopper rubber.

In a preferred aspect, the stopper rubber is a deformed portion whose outer surface shape on only one side in the vehicle front-rear direction bulges outward in the radial direction, and the outer surface of the deformed portion is an inner surface of the outer cylinder. Is in contact with According to this aspect, the stopper rubber having the deformed portion is vulcanized and molded, and the stopper rubber is pressed into the outer peripheral surface of the inner cylinder while being positioned in the circumferential direction so that the deformed portion is located in the predetermined direction. The outer surface of the stopper rubber can be brought into contact with the inner surface of the outer cylinder only on one side in the vehicle longitudinal direction by a simple means of drawing the outer cylinder as required.

In the case where the stopper rubber having the irregular shape is used, it is preferable to provide a positioning mark in order to facilitate positioning in the circumferential direction when press-fitting the inner rubber into the inner cylinder. In a preferred aspect, an outer radius of curvature of an outer surface of the irregularly shaped portion is set smaller than an inner radius of curvature of an inner surface of the outer cylinder with which the outer surface of the irregularly shaped portion abuts. By setting the outer radius of curvature of the deformed portion smaller than the inner radius of curvature of the inner surface of the outer tube where the outer surface of the deformed portion abuts, the contact area between the outer surface of the deformed portion of the stopper rubber and the inner surface of the outer tube is reduced. can do. Such a contact portion is a portion that is always in contact in a normal state where relative displacement does not occur between the inner and outer cylinders. Therefore, if the contact area is large, the resistance force due to friction between the stopper rubber and the outer cylinder is reduced. This may cause an adverse effect on the effect of absorbing vibration in the vertical direction of the vehicle. In this regard,
According to the above aspect, it is possible to reduce the contact area between the outer surface of the deformed portion of the stopper rubber and the inner surface of the outer cylinder, thereby reducing the resistance force caused by friction acting between the two, and to reduce the effect of absorbing vibration in the vertical direction of the vehicle. The adverse effects can be reduced.

The suspension bush of the present invention can be preferably manufactured by the following method. That is, the outer cylinder includes an outer cylinder, an inner cylinder disposed inside the outer cylinder, and a cylindrical rubber elastic body interposed between the outer cylinder and the inner cylinder to connect the two. A first step of vulcanizing and forming a bush body having a cylindrical hollow portion in which the rubber elastic body does not exist at one end in the axial direction between the inner cylinders; A second step of press-fitting the outer peripheral surface of the inner cylinder from one end in the axial direction while forming a cylindrical gap between the outer peripheral surface and the inner peripheral surface of the outer cylinder; and at least a portion corresponding to the stopper rubber. The outer peripheral surface of the axial end of the outer cylinder, at least a part in the circumferential direction is drawn, and the inner surface of the outer cylinder reduced in diameter by drawing is partially formed in the circumferential direction with the stopper rubber. The third step of contacting the outer surface is performed in order, so that the It is possible to produce a Deployment bush.

In this manufacturing method, in the second step, the stopper rubber is pressed into the outer peripheral surface of the inner cylinder while forming a cylindrical gap between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder. Therefore, there is no interference between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder at the time of press-fitting. Therefore, the operation of press-fitting the stopper rubber becomes easy, and the shape and posture of the original stopper rubber can be maintained without the stopper rubber being distorted at the time of press-fitting.

The shape of the outer peripheral surface of the stopper rubber to be press-fitted in the second step may be one having the above-mentioned deformed portion on its outer surface or a simple circular shape. Also, when vulcanizing a rubber elastic body between the outer cylinder and the inner cylinder, tensile stress remains at the interface between the rubber elastic body and the inner cylinder and the outer cylinder, and this tensile stress is the durability fatigue property of the rubber elastic body. Is a factor that reduces For this reason, after vulcanization molding, in order to improve the endurance fatigue resistance of the rubber elastic body, a pre-compression is applied to the rubber elastic body by usually drawing the outer peripheral surface of the outer cylinder. In the third step, the inner surface of the outer cylinder reduced in diameter by the drawing process is partially brought into contact with the outer surface of the stopper rubber in the circumferential direction by drawing the outer cylinder. The operation for bringing the rubber elastic body into contact with the inner surface of the outer cylinder and the operation for applying the pre-compression to the rubber elastic body can be easily performed in the same step.

When the stopper rubber having the deformed portion on the outer surface is press-fitted in the second step, at least a part of the outer surface of the deformed portion is brought into contact with the inner surface of the outer cylinder in the third step. The outer peripheral surface of the outer cylinder may be drawn, and when a stopper rubber is pressed into the simple circular outer peripheral shape in the second step, the outer peripheral surface of the outer cylinder is partially removed in the circumferential direction in the third step. By drawing only to the part or by drawing partly larger than many parts,
The inner surface of the outer cylinder reduced in diameter by drawing may be partially brought into contact with the outer surface of the stopper rubber in the circumferential direction.

Further, in the suspension bush of the present invention, the inner surface of the outer cylinder and the outer surface of the inner cylinder are provided in the cylindrical hollow portion provided at one axial end between the outer cylinder and the inner cylinder where the rubber elastic body does not exist. In at least one of them, a thin rubber film formed integrally with the rubber elastic body can be provided on the entire circumferential direction or a part in the circumferential direction. If, for example, a rubber film having a cylindrical cross section is provided on the outer peripheral surface of the inner cylinder, the stopper rubber as a separate body is pressed into the outer peripheral surface of the rubber film. When a rubber film is provided, the outer surface of the stopper rubber as a separate member comes into contact with the inner surface of the outer cylinder via this rubber film, and the rubber film of the outer cylinder with which the outer surface of the stopper rubber comes into contact is It can also function as a stopper rubber portion that can absorb the impact when the stopper rubber collides.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment of a suspension bush according to the present invention will be described below with reference to the drawings. In this embodiment, the suspension bush of the present invention is applied to a torch collect bush used for a torsion beam type rear suspension.

In the following description, the vehicle width direction refers to the left-right direction in FIGS. 1, 4, 5, 7, 9, and 10, and the inside or the inside in the vehicle width direction refers to the vehicle width direction. 1, 4, 5, 7, and 10, and the outside or outside in the vehicle width direction is the right side of FIGS. 1, 4, 5, 7, and 10. Say. FIG. 1 shows the vehicle longitudinal direction.
3 and FIGS. 5 to 10 refer to the vertical direction, the front side or the front refers to the upper side of FIGS. 1 to 3 and FIGS. 5 to 10, and the rear side or the rear refers to FIGS. 3. Refers to the lower side of FIGS. Further, in these figures, an arrow FR appropriately shown indicates a front side of the vehicle, an arrow WI indicates an inner side in the vehicle width direction, and an arrow TS indicates an upper side of the vehicle.

FIGS. 1, 5 and 7 show a torrect bush of this embodiment (disposed on the right side of the vehicle).
FIG. 2 is an axial cross-sectional view taken along the axis in the horizontal direction (cut along the line AA in FIG. 2), and FIG. 2 is a right side view as viewed from the right in FIG. 3 is a left side view as viewed from the left of FIG. 1, FIG. 4 is an axial sectional view taken along line BB of FIG. 2, and FIG. 6 is a right side view as viewed from the right of FIG. FIG. 8 is a right side view as viewed from the right in FIG. And
FIGS. 1 to 4 show a state after vulcanization molding of the bush body 5a, and FIGS. 5 and 6 show a state in which the stopper rubber 9 is pressed into the inner cylinder 20 of the bush body 5a. FIGS. 7 and 8 show the state in which the outer cylinder 10 of the bush main body 5a into which the stopper rubber 9 is press-fitted is drawn to complete the to collect bush of the present embodiment.

The torsion beam type rear suspension shown in FIG. 9 has a torsion beam 1 arranged longitudinally in the vehicle width direction and fixed at both ends of the torsion beam 1 in the longitudinal direction substantially in the longitudinal direction of the vehicle. And a pair of left and right trailing arms 2 and 3 as side mounting members. Cylindrical bush press-fitting portions 2a, 3a are integrally formed at the front end of each trailing arm 2, 3, and each bush press-fitting portion 2a, 3a has an axial direction coinciding with the vehicle width direction. Are press-fitted respectively (see FIG. 10). To the collect bushes 4 and 5, mounting members 6 and 7 on the vehicle body side are mounted by bolts 8 and nuts 9, respectively. Thus, the front ends of the trailing arms 2, 3 of the torsion beam type suspension are connected to the mounting members 6, 7 on the vehicle body side by the collect bushes 4, 5. Note that wheels 2b, 3b (shown in FIG. 11) are rotatably supported at the rear ends of the trailing arms 2, 3 via a spindle.

The toe collect bush 5 shown in FIG. 7 is mounted on the right trailing arm 3 and arranged on the right side of the vehicle. FIG. 7 shows a horizontal sectional structure thereof.
Note that a toe collect bush 4 having the same structure as the toe collect bush 5 shown in FIG. 7 is arranged on the left trailing arm 2 so as to be symmetrical with respect to the vehicle center plane.

The torch collect bush 5 is provided concentrically at a predetermined interval inside the outer cylinder 10 with a substantially cylindrical outer cylinder 10 fixed to the trailing arm 3, and is provided on the vehicle body side with a mounting member. 7, a bush body composed of a substantially cylindrical inner cylinder 20 fixed to and a substantially cylindrical rubber elastic body 30 disposed concentrically between the outer cylinder 10 and the inner cylinder 20 to connect them. 5a and rubber elastic body 3 provided at one axial end (outer end in the vehicle width direction) between outer cylinder 10 and inner cylinder 20
The stopper rubber 9 as a separate body accommodated in the substantially cylindrical hollow portion 5b where no “0” exists is a constituent element.

The outer cylinder 10 is made of metal, and has an inclined bent portion 11 whose inner end on the front side is obliquely bent in the range of 30 to 70 degrees to the front side, and an inner end on the rear side toward the rear side. And a right-angle bent portion 12 bent at a substantially right angle. The outer cylinder 10
(Hereinafter, referred to as “the outer cylindrical portion 1”).
3 ". ), A right angle bent portion 12 is integrally formed at the rear inner end, and an inclined bent portion 11 is integrally formed at the front inner end of the outer cylindrical portion 13.
The axial length of 0 is longer on the front side than on the rear side by the amount that the inclined bent portion 11 is inclined inward in the vehicle width direction.

The inner cylinder 20 is a metal cylindrical inner cylinder main body 2.
1 and a metal plate 22 fixed to an inner end of the inner cylinder body 21 in the vehicle width direction. The plate 22 is formed with a through hole 22a having a hole diameter substantially equal to the outer diameter of the inner cylinder main body 21. After inserting the inner cylinder main body 21 into the through hole 22a, the two are fixed by welding. . The front side of the plate 22 is formed as an inclined protruding portion 22b extending forward from the outer surface of the inner cylinder main body 21 while being inclined inward in the vehicle width direction and facing the inclined bent portion 11 of the outer cylinder 10. On the other hand, the rear side of the plate 22 is a right-angle base 22c extending rearward at right angles (radially outward) from the outer surface of the inner cylinder main body 21, and while being inclined inward in the vehicle width direction from the tip of the right-angle base 22c. Inclined intermediate portion 22d integrally extending rearward
And a right-angled tip (right-angle protruding portion) that extends again integrally at a right angle (radially outward) rearward from the tip of the inclined intermediate portion 22d and faces the right-angle bent portion 12 of the outer cylinder 10 in the vehicle width direction.
22e. Further, the upper side of the plate 22 is an upper protruding portion 22f having an upper end surface flush with the upper end surface of the right-angled tip portion 22e, and the lower side of the plate 22 is flush with the lower end surface of the right-angled tip portion 22e. The lower projection 22g has an end surface (see FIG. 3).

As shown in FIG. 2 and FIG.
0 is a front end F of the outer peripheral surface of the inner cylinder main body 21.
The right-angle bent portion 12 of the outer cylinder 10 is disposed in a range rearward of a rear end R of the outer peripheral surface of the inner cylinder main body 21. The inclined bent portion 11 of the outer cylinder 10 and the inclined protruding portion 22b of the inner cylinder 20 are both formed over a range P that exceeds 60 degrees in the circumferential direction with the axis O as a center. The portion 22d is formed over a range Q of about 60 degrees in the circumferential direction around the axis O. Further, the width d ₁ of the inclined bent portion 11 of the outer cylinder 10 and the inclined protruding portion 22b of the inner cylinder 20 in the vehicle up-down direction (the left-right direction in FIG. 3) is set slightly smaller than the diameter of the outer cylinder 13. width d ₂ in the vertical direction of the vehicle perpendicular tip 22e of the cylinder 20 is larger than the outer diameter of the inner cylinder main body 21, and the vehicle upper and lower inclined protrusion 22b of the inclined bent portion 11 and the inner cylinder 20 of the outer cylinder 10 Width d _{1 in the} direction
It is set smaller than.

The rubber elastic body 30 includes a main body rubber portion (main body portion) 31 for connecting the outer cylindrical portion 13 of the outer cylinder 10 and the inner cylindrical body 21 of the inner cylinder 20 in the radial direction, and an inclined bending of the outer cylinder 10. Part 11
Between the right angle bent portion 12 of the outer cylinder 10 and the right angle tip 22 e of the inner cylinder 20, between the right angle bent portion 12 of the outer cylinder 10 and the right angle tip 22 e of the inner cylinder 20. Width direction connecting portion 33 arranged in the vehicle and connecting them in the vehicle width direction.
Are integrally formed.

A substantially cylindrical concave portion 31a is formed in the main rubber portion 31 from the outer end in the vehicle width direction. The rubber elastic body 30 provided at one axial end (outer end in the vehicle width direction) between the outer cylinder 10 and the inner cylinder 20 is provided with the substantially cylindrical concave portion 31a.
Constitutes a cylindrical hollow portion in which there is no. And, on the bottom surface (the inner end surface in the vehicle width direction) of the substantially cylindrical concave portion 31a,
As shown in FIG. 2, a pair of wide recesses 31b, 31b, which are wide in the circumferential direction so as to face each other in the vehicle longitudinal direction in the radial direction.
Are extended along the axis, and a pair of narrow recesses 31c, 31c having a narrow width in the circumferential direction are formed along the axis so as to oppose the vehicle in the radial direction (vertical direction in FIG. 2). It has been extended. These wide recesses 31b and narrow recesses 3
1c is for adjusting the spring characteristics of the main body rubber portion 31 in the vehicle front-rear direction and the vehicle vertical direction, and the size thereof can be appropriately set. In particular, in the present embodiment, each wide concave portion 31b facing in the vehicle front-rear direction is
Since the width in the circumferential direction is wider than the narrow recesses 31c opposed in the vehicle vertical direction, the main rubber portion 31
Is set smaller in the vehicle longitudinal direction than in the vehicle vertical direction. By doing so, it is possible to achieve the function and effect of ensuring front-to-back compliance.

The main rubber portion 31 has both the inner surface of the outer cylindrical portion 13 of the outer tube 10 and the outer surface of the inner cylindrical body 21 of the inner tube 20 at the substantially cylindrical concave portion 31a serving as the cavity. The rubber films 31d and 31e, which are formed integrally with the main rubber portion 31 and have a thin-walled shape and a substantially cylindrical cross section, are provided in the entire circumferential direction. The rubber film 31d provided on the inner surface of the outer cylindrical portion 13 functions as a stopper rubber portion that can absorb an impact when the outer surface of the stopper rubber 9 collides. Here, a rubber film 31d that can function as the stopper rubber portion
Are thick rubber films 31f, 31f, each of which is slightly thicker than a portion which opposes in the vehicle vertical direction, respectively.

The inclined connecting portion 32 is disposed in a range forward of the front end F of the outer peripheral surface of the inner cylinder main body 21, similarly to the inclined bent portion 11 of the outer cylinder 10 and the inclined protruding portion 22b of the inner cylinder 20. In addition, it is formed over a range P exceeding 60 degrees in the circumferential direction around the axis O. The width of the inclined connecting portion 32 in the vehicle vertical direction is also the same width d ₁ as the inclined bent portion 11 and the inclined protruding portion 22b.

The width-direction connecting portion 33 continuously connects the entire right-angled end portion 22e of the inner cylinder 20 and the right-angle bent portion 12 of the outer cylinder 10 in the vehicle width direction. And the width direction connecting portion 33
Is disposed in a range on the rear side of the rear end R of the outer peripheral surface of the inner cylinder main body 21 in the same manner as the right-angled bent portion 12 of the outer cylinder 10. It is formed over a range Q of about 60 degrees in the circumferential direction around the center O. Furthermore, the width in the vertical direction of the vehicle width direction connecting portion 33, which is smaller than the width d ₁ in the vehicle vertical direction of the slant connection portion 32 is the width d ₂ of the same perpendicular tip 22e, thereby tilting The toe-collecting function of the connecting portion 32 can be effectively exerted.

As shown in FIG. 4, the rubber body 31 has an outer peripheral surface of the inner cylinder main body 21 located inside the inner end of the outer cylinder 13 of the outer cylinder 10 in the vehicle width direction. The upper projection 2 of the inner cylinder 20 is provided at a portion facing the vehicle in the vertical direction.
An upper covering portion 34 and a lower covering portion 35 are integrally formed so as to cover the 2f and the lower protruding portion 22g, respectively.
The upper end surface of the upper covering portion 34 is flush with the upper end surface of the width direction connecting portion 33, and the lower end surface of the lower covering portion 35 is flush with the lower end surface of the width direction connecting portion 33. An upper concave portion 34a and a lower concave portion 35a are formed between the outer end surfaces of the upper covering portion 34 and the lower covering portion 35 in the vehicle width direction and the inner end surfaces of the main rubber portion 31 in the vehicle width direction. The upper concave portion 34a and the lower concave portion 35a are provided for improving the durability of the peripheral portion.

The stopper rubber 9 accommodated in the substantially cylindrical concave portion 31a, which is the hollow portion, is press-fitted into the outer peripheral surface of a rubber film 31e provided on the outer peripheral surface of the inner cylinder main body 21 of the inner cylinder 20. The outer surface shape of only one side in the front-rear direction, in this embodiment, only the front side is a deformed portion 9a that bulges outward in the radial direction, and the outer surface of the deformed portion 9a is partially formed in the outer cylinder 10 in the circumferential direction. Is in contact with a thick rubber film 31f provided on the inner surface of the outer cylindrical portion 13.

The outer radius of curvature of the outer surface of the deformed portion 9a is larger than the radius of curvature of the outer peripheral surface of the inner cylinder body 21 of the inner cylinder 20, and the thick rubber film 31f in contact with the outer surface of the deformed portion 9a. It is set smaller than the inner radius of curvature on the inner surface. The stopper rubber 9 has a built-in cylindrical metal ring 9b in order to increase the rigidity of the stopper rubber 9 itself.

The collect bush 5 having the above configuration
Was manufactured as follows. First, in a first step, a plate 22 having a predetermined shape is fixed to the inner cylinder main body 21 by welding, and then the inner cylinder 20 and the outer cylinder 10 formed into a predetermined shape are arranged in a predetermined vulcanization mold. , Rubber elastic body 3
In addition, the rubber elastic body 30 and the outer cylinder 10 and the inner cylinder 20 are vulcanized and bonded together, and one end in the axial direction between the outer cylinder 10 and the inner cylinder 20 (the outer end in the vehicle width direction). )
A bush body 5a in which a substantially cylindrical concave portion 31a or the like, which is a cylindrical hollow portion having no rubber elastic body 30, is provided in the rubber elastic body 30 by vulcanization molding. This state is shown in FIG.
4 to FIG.

In the second step, the stopper rubber 9 formed into a predetermined shape by vulcanization molding is combined with the outer peripheral surface of the stopper rubber 9 and the inner peripheral surface of the outer cylinder 10 (the rubber film 31d and the thick rubber film 31f). The inner cylinder 20 was press-fitted from one axial end (outer end in the vehicle width direction) to the outer peripheral surface (outer peripheral surface of the rubber film 31e) while forming a cylindrical gap between the inner cylinder 20 and the inner peripheral surface. This state is shown in FIG. 5 and FIG.

Finally, in the third step, the outer circumferential surface of about half of the outer cylindrical portion 13 of the outer cylinder 10 at one end in the axial direction (outer end in the vehicle width direction) is made uniform over the entire circumferential direction. It was drawn. As a result, of the outer peripheral surface of the stopper rubber 9, only a part of the outer surface of the deformed portion 9 b is brought into contact with the inner surface of the outer cylinder 10 (the inner surface of the thick rubber film 31 f), and the torch-collect bush 5 according to the present embodiment. Was completed. This state is shown in FIG. 7 and FIG.

And, this collect bush 5
As shown in FIG. 10, the inclined bent portion 11 and the inclined protrusion 22
The outer cylindrical portion 13 of the outer cylinder 10 is press-fitted into the bush press-fit portion 3a of the trailing arm 3 on the right side in the vehicle width direction so that the b and the inclined connecting portion 32 are located inside the vehicle width direction. The inner cylinder main body 21 of the cylinder 20 is attached to the attachment member 7 on the vehicle body side with the bolts 8 and the nuts 9.

In the toe collect bush 5, the stopper rubber 9 fixes the outer peripheral surface of the stopper rubber 9 and the inner peripheral surface of the outer cylinder 10 to each other, so that the two members are fixed to each other, and the relative movements of the two members are relative to each other. The spring constant of the bush in the vehicle front-rear direction is smaller than in the case where the restriction is imposed. Since a gap c is formed between the outer peripheral surface of the stopper rubber 9 and the inner peripheral surface of the outer cylinder 10 on the rear side of the front and rear of the vehicle, the outer cylinder 10 and the Inner cylinder 2
When 0 is relatively displaced, the rubber to be compressed does not exist by the amount of the gap, and the spring constant of the bush in the vehicle front-rear direction decreases accordingly. Therefore, in the toe collect bush 5 of the present embodiment, the compliance before and after the suspension is increased, and the harshness can be effectively absorbed.

On the other hand, the outer peripheral surface of the stopper rubber 9 and the outer cylinder 10
The outer surface of the stopper rubber 9 and the inner surface of the outer cylinder 10 abut on the front side of the front and rear of the vehicle between the inner cylinder 20 and the inner cylinder 20. In the case of relative displacement, the outer surface of the stopper rubber 9 and the inner surface of the outer cylinder 10 are in contact with each other in advance, so that they do not collide with each other.
There is no occurrence of a shock sensation due to an impact when the two collide. When the inner cylinder 20 is displaced relative to the outer cylinder 10 on the rear side of the front and rear of the vehicle, that is, on the side where the gap c is formed between the outer surface of the stopper rubber 9 and the inner surface of the outer cylinder 10. When the outer surface of the stopper rubber 9 collides with the inner surface of the outer cylinder 10, the thick rubber film 31f provided on the inner surface of the outer cylinder 10 effectively absorbs the impact at the time of the collision. Thus, it is possible to reduce a shock caused by an impact at the time of such a collision.

As described above, in the toe collect bush 5 of the present embodiment, the front side (the stopper rubber 9) of the vehicle front and rear.
Of the outer cylinder 10 and the inner surface of the outer cylinder 10).
When the inner cylinder 20 is relatively displaced with respect to the vehicle, a sense of shock when the outer surface of the stopper rubber 9 collides with the inner surface of the outer cylinder 10 can be eliminated, and the rear side of the front and rear of the vehicle (the stopper rubber 9 Of the inner cylinder 2 with respect to the outer cylinder 10 on the side where the gap c is formed between the outer surface of the
In the case where 0 is relatively displaced, the shock feeling when the outer surface of the stopper rubber 9 collides with the inner surface of the outer cylinder 10 can be reduced.

Therefore, according to the toe collect bush of this embodiment, the provision of the separate stopper rubber 9 makes it possible to effectively absorb the harshness while suppressing the problem of a newly generated shock feeling. Further, since the stopper rubber 9 is provided with the deformed portion 9a, the outer cylinder 10
The outer surface of only the deformed portion 9a of the stopper rubber 9 can be abutted against the inner surface of the outer cylinder 10 by uniformly drawing the outer peripheral surface of the outer peripheral surface in the entire circumferential direction, so that the drawing process is easy. Becomes

Further, the outer radius of curvature of the outer surface of the deformed portion 9a is set smaller than the inner radius of curvature of the inner surface (the inner surface of the thick rubber film 31f) of the outer cylinder 10 with which the outer surface of the deformed portion 9a contacts. Since the contact area between the outer surface of the deformed portion 9a and the inner surface of the thick rubber film 31f is reduced, the resistance force due to friction acting between the two can be reduced, and the effect of absorbing vibration in the vertical direction of the vehicle can be reduced. The adverse effects can be reduced.

In addition, at the stage of press-fitting the stopper rubber 9 into the inner cylinder 20, since a predetermined gap exists between the outer peripheral surface of the stopper rubber 9 and the inner peripheral surface of the outer cylinder 10, The press-in operation of the press-in 9 becomes easy, and the stopper rubber 9 is not deformed at the time of press-in. Further, a drawing process of the outer cylinder 10 for bringing the inner surface of the outer cylinder 10 into contact with the outer surface of the deformed portion 9a of the stopper rubber 9, and a rubber elastic body 30
Can be performed simultaneously with the drawing of the outer cylinder 10 for improving the durability fatigue of the rubber elastic body 30 by applying preliminary compression to the rubber, so that the entire manufacturing process can be simplified.

On the other hand, in this collect bush 5,
The inclined bent portion 11 of the outer cylinder 10 and the inclined protrusion 2 on the inner cylinder 20 side
2b, the inclined connecting portion 32 of the rubber elastic body 30 is compressed.
The outer cylinder 10 and the inner cylinder 2
The relative displacement in the vehicle width direction and the relative displacement in the vehicle front-rear direction between 0 can be mutually converted. As a result, a toe-collect function is exhibited, and oversteer during turning of the vehicle can be reduced.

FIG. 11 shows such a collect function.
This will be described below with reference to a schematic view of a torsion beam type rear suspension shown in FIG. FIG. 11A shows the movement of the twist beam 1 and the like when the bushes Bl and Br having no toe-collect function are used, and FIG. 11B shows the toe-collect bush having the toe-collect function. 4 shows the movement of the twist beam 1 and the like when using 4, 5;

Bush B having no to collect function
In the torsion beam type rear suspension using l and Br, as shown in FIG. 11 (a), the left and right wheels 2b, 3b
When a rightward lateral force F acts on the right bush Br, a forward and backward longitudinal force of Fx (= 2 × F × L / D) acts on the right bush Br. The front-rear force Fx is equal to the arm length of the trailing arms 2 and 3 (in FIG.
L and the distance between the left and right bushes Br and Bl are D. On the other hand, Fx (= 2 × F ×
L / D) is exerted. Therefore, the right-side bush Br is displaced forward and the left bush Bl is displaced rearward by these front-rear direction forces Fx. Therefore, the torsion beam 1 rotates counterclockwise around the center in the vehicle width direction, and the steer angle changes in the oversteer direction.

In order to reduce such oversteer, when a rightward lateral force F acts on the left and right wheels 2b, 3b, a rightward rightward force Fy is applied to the right bush Br.
Acts on the left bush Bl to the right while the right-handed left-right force Fy acts on the left bush Bl. What is necessary is just to give the characteristic which also displaces ahead. This allows the torsion beam 1 to rotate clockwise to correct the steer angle in the understeer direction.

Such characteristics can be exhibited by the torch collect bushes 4 and 5 having a torch collect function. That is, if the right and left wheels 2b and 3b are also subjected to the rightward lateral force F, the right toecorrection bush 5 is applied with the rightward and leftward lateral force Fy by using the toecorrection bushes 4 and 5 having the toecorrection function. Acts, it is displaced rightward and backward, and the left collect bush 4 on the left side exerts a rightward left-right force F
When y acts, it is displaced rightward and displaced forward.

More specifically, in the right collect bush 5 shown in FIG. 10, a rightward left-right force acts via the trailing arm 3 so that the outer cylinder 10 10 to the right (outside in the vehicle width direction). At this time, the inclined connecting portion 32 that connects the inclined bent portion 11 of the outer cylinder 10 and the inclined protruding portion 22b of the inner cylinder 20 in an oblique direction has a repulsive force when pulled in the left-right direction (vehicle width direction). The outer cylinder 10 is relatively displaced rearward with respect to the inner cylinder 20 because the outer cylinder 10 acts as the rearward and frontward force Fx. On the other hand, in the toe collect bush 4 on the left side, the outer cylinder 10 is relatively displaced rightward (inward in the vehicle width direction) with respect to the inner cylinder 20 due to the rightward left-right force acting via the trailing arm 2. I do. At this time, the outer cylinder 10
The inclined connecting portion 32 that connects the inclined bent portion 11 of the inner cylinder 20 and the inclined protruding portion 22b of the inner cylinder 20 in an oblique direction has a repulsive force when compressed in the left-right direction (vehicle width direction) with a forward-backward force Fx. Therefore, the outer cylinder 10 is relatively displaced forward with respect to the inner cylinder 20.

In this way, the torsion beam 1 can be rotated clockwise to correct the steer angle in the understeer direction. As a result, as shown in FIG. 11B, the rotation of the torsion beam 1 is eliminated and the change in the steer angle is eliminated. It becomes possible. In addition, this collect bush 5
In this embodiment, the right-angle bent portion 12 of the outer cylinder 10 and the right-angle tip portion 22e, which is a right-angle projection of the inner cylinder 20, are connected in the vehicle width direction by the width-direction connecting portion 33 of the rubber elastic body 30. For this reason, the rubber elastic body 3
The spring characteristics in the vehicle width direction due to 0 greatly depend on the compression / spring characteristics in the width direction connecting portion 33 in addition to the shearing spring characteristics in the main body rubber portion 31 and the compression / tensile spring characteristics in the inclined connecting portion 32. . That is, when a relative displacement occurs between the outer cylinder 10 and the inner cylinder 20 in the vehicle width direction, the rigidity in the vehicle width direction can be increased by an amount corresponding to the action of the compression and tension applied to the width direction connecting portion 33.

Therefore, even if the vehicle has a high inertial force during turning, such as a heavy vehicle or a high vehicle, the relative displacement in the vehicle width direction between the outer cylinder 10 and the inner cylinder 20 during the vehicle turning. , And oversteer can be suppressed to improve steering stability. further,
In the present embodiment, the plate 22 is provided with an inclined intermediate portion 22d which is inclined inward in the vehicle width direction, and a right-angled tip portion 22e which is a right-angled projecting portion is provided at the tip of the inclined intermediate portion 22d. The space in the vehicle width direction between the right-angled tip portion 22e and the right-angled bent portion 12 of the outer cylinder 10 is increased by the amount of the inclination of the portion 22. Therefore. The volume in the vehicle width direction of the width-direction connecting portion 33 provided between the right-angled tip portion 22e and the right-angle bent portion 12 can be increased to increase the volume, and the durability of the width-direction connecting portion 33 can be improved. It is advantageous in improving.

In the above-described embodiment, an example has been described in which the outer surface of the stopper rubber 9 and the inner surface of the outer cylinder 10 abut only on the front side in the vehicle front-rear direction. Of course, the stopper rubber 90 and the outer cylinder 10 can be brought into contact with each other, and in this case, the same operation and effect can be obtained.

[0057]

As described in detail above, the suspension bush of the present invention has a separate stopper rubber because the stopper rubber and the outer cylinder are in contact with only one of the front and rear sides of the vehicle. It exhibits effective absorption characteristics for harshness while suppressing the problem of newly generated shock feeling.

[Brief description of the drawings]

FIG. 1 relates to a toe collect bush (disposed on the right side of a vehicle) of the present embodiment in which a suspension bush of the present invention is applied to a toe collect bush, and a bush body is cut horizontally along an axis (see FIG. 1). FIG. 2 is a sectional view in the axial direction (taken along line AA of FIG. 2).

FIG. 2 is a right side view of the bush body viewed from the right in FIG.

FIG. 3 is a left side view of the bush body viewed from the left in FIG.

FIG. 4 is an axial sectional view of the bush body taken along line BB in FIG. 2;

5 shows a state in which a stopper rubber is press-fitted into the inner cylinder of the bush main body, which is cut in a horizontal direction along an axis (A- in FIG. 2).
FIG. 3 is an axial cross-sectional view (taken along line A).

FIG. 6 is a right side view of the state in which a stopper rubber is press-fitted into the inner cylinder of the bush body as viewed from the right in FIG.

FIG. 7 is an axial sectional view of the torch collect bush cut along the axis in the horizontal direction (cut along the line AA in FIG. 2).

FIG. 8 is a right side view of the collect bush as viewed from the right in FIG. 7;

FIG. 9 is a plan view showing the overall configuration of a torsion beam type rear suspension using the torch collect bush.

FIG. 10 is a partial cross-sectional view showing a state where the torch collect bush is attached to a right training arm of a torsion beam type rear suspension.

11A and 11B are schematic diagrams of a torsion beam type rear suspension, in which FIG. 11A shows a movement of a twist beam or the like when a bush having no toe correct function is used, and FIG. 11B shows a toe correct function. FIG. 3 shows the movement of a twist beam or the like when a torch collect bush is used.

FIG. 12 is an axial cross-sectional view of a conventional torch collect bush (disposed on the right side of the vehicle) cut in a horizontal direction along an axis.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 torsion beam 2, 3 trailing arm 4, 5 collect bush 5 a bush body 6, 7 mounting member 9 stopper rubber 9 a deformed portion 10 outer cylinder 11 inclined bent portion 12 right angle bent portion 13 ... outer cylinder cylindrical part 20 ... inner cylinder 21 ... inner cylinder main body 22b ... inclined projection part 22e ... right-angled tip part 30 ... rubber elastic body 31 ... main body rubber part 31a ... substantially cylindrical concave part (hollow part) 32 ... inclined connection part 33 … Width direction connecting part

Claims (4)

[Claims] 1. A bush which is disposed so that an axial direction thereof coincides with a vehicle width direction and connects a first mounting member on a suspension side and a second mounting member on a vehicle side. An outer cylinder fixed to one of the second mounting members, and an inner cylinder disposed inside the outer cylinder and fixed to the other of the first mounting member and the second mounting member; A suspension bush comprising a cylindrical rubber elastic body interposed between the outer cylinder and the inner cylinder and connecting the two, wherein the rubber elastic member is provided at one axial end between the outer cylinder and the inner cylinder. A cylindrical stopper rubber press-fitted from one end in the axial direction to the outer peripheral surface of the inner cylinder is housed in the cylindrical hollow portion where the body does not exist, and the stopper rubber has an outer surface on only one side in the vehicle longitudinal direction. Suspension characterized by being in contact with the inner surface of the outer cylinder Mesh. 2. The stopper rubber according to claim 1, wherein the outer surface of only one side in the front-rear direction of the vehicle is a deformed portion that bulges outward in the radial direction, and an outer surface of the deformed portion contacts an inner surface of the outer cylinder. The suspension bush according to claim 1, wherein the suspension bush is provided. 3. The outer radius of curvature of the outer surface of the deformed portion is set smaller than the inner radius of curvature of the inner surface of the outer cylinder with which the outer surface of the deformed portion abuts. Suspension bush. 4. An outer cylinder, an inner cylinder disposed inside the outer cylinder, and a cylindrical rubber elastic body interposed between the outer cylinder and the inner cylinder to connect the both. A first step of obtaining by vulcanizing a bushing body having a cylindrical cavity in which the rubber elastic body does not exist at one end in the axial direction between the outer cylinder and the inner cylinder; A second step of press-fitting the outer peripheral surface of the inner cylinder from one end in the axial direction while forming a cylindrical gap between the outer peripheral surface of the stopper rubber and the inner peripheral surface of the outer cylinder; The outer peripheral surface of the axial end of the outer cylinder in the portion to be drawn, at least a part in the circumferential direction is drawn, and the inner surface of the outer cylinder reduced in diameter by drawing is partially removed in the circumferential direction. And a third step of contacting the outer surface of the stopper rubber with the third step. Method of manufacturing a Deployment bush.