JP4638270B2 - Elastic bush - Google Patents

Description

The present invention is arranged so that the inner tube and a suspension arm which is fixed to the outer cylinder fixed to the vehicle body is displaced relative to the longitudinal direction of the vehicle body, resilient outer peripheral surface of the inner peripheral surface and the inner cylinder of the outer cylinder It relates to an elastic bush connected by the body.

Of the front and rear suspension bushes that elastically support the front and rear ends of the bifurcated lower arm of the suspension device, the front suspension bush includes an inner cylinder fixed to the vehicle body with a vertically extending bolt, and a lower arm Consists of an outer cylinder that is fixed by press-fitting into a mounting hole formed at the front end, and an elastic body that connects the inner cylinder and the outer cylinder, and a spring (space portion) for reducing the spring constant is formed in the elastic body. This is known from the following patent document 1.
JP 2004-308825 A

  By the way, if the elastic body is formed with a curl, the rigidity in the direction perpendicular to the axis of the elastic bushing can be reduced to increase the front-rear compliance of the wheel. There was a possibility of undesired movement.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to make it possible to arbitrarily set the rigidity in the axial direction of the elastic bush and the rigidity in the direction orthogonal to the axis.

In order to achieve the above object, according to the invention described in claim 1, the inner cylinder fixed to the vehicle body and the outer cylinder fixed to the suspension arm are arranged so as to be relatively displaced in the longitudinal direction of the vehicle body, the elastic bushing the inner and outer peripheral surfaces of the inner cylinder are connected by an elastic body of the outer cylinder, the elastic body is the radially outer end is connected to the outer cylinder radially inner end to the inner tube are connected, and a plate-shaped wall portion inclined at a predetermined angle of inclination relative to a plane perpendicular to the axis of the outer cylinder and the inner cylinder, adjacent in the circumferential direction on the plate-shaped wall portion, of the outer cylinder A solid portion having no space between the peripheral surface and the outer peripheral surface of the inner cylinder, the plate-like wall portion is disposed in the longitudinal direction of the vehicle body across the axis, and the solid portion is elastic bushes proposed is characterized in that it is arranged in the lateral direction of the vehicle body across the axis That.

According to the invention described in claim 2, in addition to the configuration of claim 1, the plate-like wall portion includes a first plate-like wall portion and a first plate-like wall portion arranged symmetrically with respect to a plane orthogonal to the axis. The first plate-like wall portion and the second plate-like wall portion, which are configured by two plate-like wall portions, are connected to the inner cylinder, the covering portion covering the outer peripheral surface of the inner cylinder, and the covering portion An elastic bushing is proposed, which is thicker and has a stopper portion interposed between the first plate-like wall portion and the second plate-like wall portion in the axial direction .

According to the invention described in claim 3, in addition to the configuration of claim 1 or claim 2, before Symbol elastic body, the central portion of the plate-shaped wall portion of the front and rear of said axis, said There is proposed an elastic bushing characterized by having a straight through the plate wall in a direction parallel to the axis .

  The lower arm 12 of the embodiment corresponds to the suspension arm of the present invention, and the first and second plate-like wall portions 35a and 35b of the embodiment correspond to the plate-like wall portion of the invention, and the second symmetry of the embodiment. The plane P2 corresponds to a plane orthogonal to the axis of the present invention.

According to the configuration of claim 1, the plate-like wall portion inclined at a predetermined inclination angle with respect to the plane orthogonal to the axis of the outer cylinder and the inner cylinder, and adjacent to the plate-like wall portion in the circumferential direction, The suspension arm is provided with an elastic bushing having a solid portion that does not have a space between the inner peripheral surface and the outer peripheral surface of the inner cylinder, and the plate-like wall portion is disposed in the longitudinal direction of the vehicle body across the axis. The solid part is arranged in the left-right direction of the vehicle body. As a result, when a load in the left-right direction of the vehicle body is input from the wheel, it is possible to prevent the elastic body from being greatly deformed by the solid portion, and to ensure steering stability. In the case of input, the plate-like wall portion allows deformation of the elastic body, suppresses vibration associated with load input, and secures riding comfort. Moreover, the compliance in the longitudinal direction of the vehicle body and the rigidity in the axial direction can be adjusted according to the inclination angle of the plate-like wall portion.

According to the configuration of the second aspect, since the plate-like wall portion of the elastic body is composed of the first plate-like wall portion and the second plate-like wall portion arranged symmetrically with respect to the plane orthogonal to the axis, The plate-like wall portion and the second plate-like wall portion can be uniformly deformed to prevent the outer cylinder and the inner cylinder from being inclined with respect to each other. In addition, the portion where the first plate-like wall portion and the second plate-like wall portion are connected to the inner cylinder includes a covering portion that covers the outer peripheral surface of the inner cylinder, and is thicker than the covering portion and is first in the axial direction. Since it has the stopper part interposed between the plate-like wall part and the second plate-like wall part, it is possible to prevent excessive deformation of the elastic body when the input load exceeds the set value.

According to the configuration of the third aspect , since the elastic body has a straight portion that passes through the plate-like wall portion in a direction parallel to the axial line at the center portion of the plate-like wall portion at the front and rear of the axis line, The front and rear compliances of the wheel can be further enhanced by easily deforming the front and rear portions of the body axis line.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 7 show an embodiment of the present invention. FIG. 1 is a perspective view of a double wishbone suspension of a left rear wheel, FIG. 2 is an enlarged view in two directions in FIG. 1, and FIG. 4 is a sectional view taken along line 4-4 of FIG. 3, FIG. 5 is a sectional view taken along line 5-5 of FIG. 3, FIG. 6 is a sectional view taken along line 6-6 of FIG. 3 is a cross-sectional perspective view taken along line 7-7.

  As shown in FIG. 1, the double wishbone suspension device S includes a knuckle 14 supported by a vehicle body by an upper arm 11 and a lower arm 12. The knuckle 14 includes an axle support portion 14a that rotatably supports the axle of the wheel W, and an upper arm support portion 14b that extends upward from the axle support portion 14a. A ball joint 16 is attached to the upper end of the upper arm support portion 14b. Thus, the outer end in the vehicle width direction of the upper arm 11 is pivotally supported, and the outer end in the vehicle width direction of the lower arm 12 is pivotally supported via the ball joint 17 at the lower end of the axle support portion 14a.

  As shown in FIG. 2, the lower arm 12 is a so-called A-type arm in which a rear arm 12a and a front arm 12b are arranged in a bifurcated manner, and the rear arm 12a is supported by the vehicle body via a first suspension bush 21. The front arm 12 b is supported on the vehicle body via the second suspension bush 22.

  The first suspension bush 21 is formed by connecting the outer peripheral surface of the inner cylinder 23 and the inner peripheral surface of the outer cylinder 24 with an elastic body 25, and a bolt 26 extending in the longitudinal direction of the vehicle body is a fork-like shape of the rear arm 12 a of the lower arm 12. The support portion 12 c and the inner cylinder 23 are passed through and fastened with a nut 27. The outer cylinder 24 is fixed by press-fitting into an annular mounting hole formed in a bracket (not shown) on the vehicle body side.

  The second suspension bush 22 is formed by connecting the outer peripheral surface of the inner cylinder 28 and the inner peripheral surface of the outer cylinder 29 with an elastic body 30, and the outer cylinder 29 is press-fitted into the annular support portion 12 d of the front arm 12 b of the lower arm 12. The bolt 31 extending in the vertical direction passes through the inner cylinder 28 and is fixed to a bracket (not shown) on the vehicle body side with a nut.

  Next, the structure of the elastic body 30 of the second suspension bush 22 will be described with reference to FIGS. The elastic body 30 has a longitudinally symmetrical structure with respect to the first symmetry plane P1 extending in the left-right direction of the vehicle body, and is vertically symmetrical with respect to the second symmetry plane P2 perpendicular to the axis L of the second suspension bushing 22. It has a structure.

  As apparent from FIGS. 3, 4, and 7, in the region A, the elastic body 30 is a solid part 32 having no space, and the two solid parts 32 are provided on both sides in the left-right direction of the vehicle body. positioned.

  As is apparent from FIGS. 3, 5, and 7, the elastic body 30 covers the outer surface of the inner cylinder 28 in a portion excluding the region C in the region B, and the upper and lower covering portions 33. A sandwiched thick stopper portion 34 and first and second plate-like wall portions 35 a and 35 b extending obliquely from the stopper portion 34 and continuing to the inner surface of the outer cylinder 29 and having a certain thickness are provided. The first and second plate-like wall portions 35a and 35b have a shape constituting a part of a cone, and are arranged vertically symmetrically with respect to the second symmetry plane P2. An angle θ formed by the first and second plate-like wall portions 35a and 35b with respect to the second symmetry plane P2 is larger than 45 °.

  As apparent from FIGS. 3, 6 and 7, the first and second plate-like wall portions 35a and 35b are cut off in the central region C of the region B, and the first and second plate-like walls are cut off at that portion. A curb 36 that penetrates the portions 35a and 35b up and down is formed. The two curls 36 are located on both sides in the longitudinal direction of the vehicle body. A thick stopper portion 34 is formed on the inner cylinder 28 facing the curl 36 so as to be opposed to the exposed inner peripheral surface of the outer cylinder 29, and an elastic body 30 is placed on the outer cylinder 29 facing the curb 36. When molding, an opening 29a is formed for removing sand that forms a space surrounded by the upper and lower plate-like wall portions 35a and 35b.

  Now, when the wheel W gets over the road surface unevenness or when the wheel W is suddenly braked, a load in the longitudinal direction of the vehicle body acts on the second suspension bush 22 and the inner cylinder 28 and the outer cylinder 29 are applied. Is relatively displaced in the longitudinal direction of the vehicle body, and the region B of the elastic body 30 is compressed and expanded in the radial direction. At this time, in the region B, the straight 36 and the first and second plate-like wall portions 35a and 35b are arranged, and the angle θ formed by the plate-like wall portions 35a and 35b with respect to the second symmetry plane P2 is 45. Since it is larger than °, the plate-like wall portions 35a and 35b can be easily bent and deformed to effectively increase the front-rear compliance of the wheel W. At this time, since the solid portions 32 of the region A are disposed at both ends of the elastic body 30 in the left-right direction of the vehicle body, the front and rear compliance of the wheel W is not lowered by the solid portions 32. When the load in the front-rear direction exceeds the set value, the inner peripheral surface of the outer cylinder 29 comes into contact with the stopper portion 34 and suppresses excessive deformation of the elastic body 30. In addition, even if a load in the direction of the axis L is applied, the slip 36 is hardly deformed, so that the rigidity of the elastic body 30 in the direction of the axis L is not reduced by the curl 36.

  As described above, by changing the angle θ formed by the first and second plate-like wall portions 35a and 35b of the elastic body 30 with respect to the second symmetry plane P2, the rigidity of the elastic body 30 in the longitudinal direction of the vehicle body and the vertical Directional rigidity can be arbitrarily adjusted. That is, as the angle θ approaches 90 °, the elastic body 30 is easily deformed in the front-rear direction and is difficult to be deformed in the up-down direction. Conversely, as the angle θ approaches 0 °, the elastic body 30 is less likely to be deformed in the front-rear direction and is more likely to be deformed in the up-down direction.

  If the elastic body 30 has only one of the first and second plate-like wall portions 35a and 35b, the relative positions of the inner cylinder 28 and the outer cylinder 29 are shifted in the direction of the axis L when an external force is applied. However, by providing the first and second plate-like wall portions 35a and 35b symmetrically with respect to the second symmetry plane P2, it is possible to prevent the displacement of the inner cylinder 28 and the outer cylinder 29 in the axis L direction. .

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, in the embodiment, the elastic bush for the suspension device is illustrated, but the present invention can be applied to an elastic bush for any other purpose.

Perspective view of left wish wheel double wishbone suspension 2 direction enlarged view of FIG. Part 3 enlarged view of FIG. Sectional view taken along line 4-4 in FIG. Sectional view along line 5-5 in FIG. 6-6 sectional view of FIG. 7 is a cross-sectional perspective view taken along line 7-7 in FIG.

12 Lower arm (suspension arm)
28 Inner cylinder 29 Outer cylinder 30 Elastic body 35a First plate-like wall (plate-like wall)
35b Second plate wall (plate wall)
36 Straight L Axis P2 Second symmetry plane (plane perpendicular to the axis)
θ Predetermined tilt angle

Claims (3)

The inner cylinder (28) fixed to the vehicle body and the outer cylinder (29) fixed to the suspension arm (12) are arranged so as to be relatively displaced in the longitudinal direction of the vehicle body,
The elastic bushing connected by an elastic body (30) the outer peripheral surface of the inner peripheral surface and the inner cylinder of the outer cylinder (29) (28),
It said elastic body (30), radially inner end connected to the outer cylinder radially outer end (29) connected to the inner tube (28), and the outer cylinder (28) and the inner tube ( plate wall portion inclined at a predetermined inclination angle (theta) with respect to the plane (P2) perpendicular to the axis of 29) (L) and (35a, 35b),
A solid portion (32) adjacent to the plate-like wall portions (35a, 35b) in the circumferential direction and having no space between the inner peripheral surface of the outer tube (28) and the outer peripheral surface of the inner tube (28). )
The plate-like wall portions (35a, 35b) are disposed in the vehicle longitudinal direction with the axis (L) interposed therebetween, and the solid portion (32) is disposed in the vehicle body lateral direction with the axis (L) interposed therebetween. elastomeric bushing, characterized in that that. The plate-like wall portions (35a, 35b) are arranged symmetrically with respect to a plane (P2) perpendicular to the axis (L), and the first plate-like wall portion (35a) and the second plate-like wall portion (35b). Consists of
In a portion where the first plate-like wall portion (35a) and the second plate-like wall portion (35b) are connected to the inner cylinder (28), a covering portion (33) covering the outer peripheral surface of the inner cylinder (28). And a stopper interposed between the first plate-like wall portion (35a) and the second plate-like wall portion (35b) in the direction of the axis (L). The elastic bush according to claim 1, comprising a portion (34) . Before SL elastic body (30), front and rear of the plate-like wall portion of the axis (L) (35a, 35b) at the central portion of the plate-shaped wall portion (35a, 35b) to the axis (L) 3. Elastic bushing according to claim 1 or 2, characterized in that it has a tickling (36) that penetrates in a direction parallel to the elastic bushing.

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