JP2006160008A - Suspension arm supporting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the rigidity of a downward suspension stroke without using a rebound spring or the like. <P>SOLUTION: In the suspension arm supporting structure, a lower link 4 of a suspension is connected to a vehicle body through a cylindrical bush 20 so as to be pivotable relative to vertical stroke of a wheel 2. A restriction means for restricting displacement of the bush 20 generated by the downward stroke of the wheel 2 than displacement of the bush 20 generated by the upward stroke of the wheel 2 is provided. Thereby, contact of the bush 20 relative to the stroke of the lower link 4 associated with rebounding of the wheel 2 is restricted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a suspension arm support structure that supports a suspension arm of a vehicle via a bush.

Conventionally, by arranging a rebound spring at the piston rebound end in the cylinder of the shock absorber, when the piston rod is in the most protruding state with respect to the cylinder when the movement of the piston rod is regulated by the rebound spring, the piston It is known to prevent so-called bottom-out collision with a cylinder (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 8-74917

However, in the above-described conventional device, since the rebound spring is provided in the cylinder, there is an unsolved problem that the amount of space and weight is disadvantageous by the built-in amount of the rebound spring.
Therefore, the present invention has been made paying attention to the above-mentioned unsolved problems of the conventional example, and provides a suspension arm support structure capable of increasing the rigidity of a suspension stroke in a certain direction without using a rebound spring or the like. The purpose is to do.

  In order to achieve the above object, the suspension arm support structure according to the present invention is a restricting means, wherein the bush member is generated by a downward stroke of the wheel due to a displacement of the bush member generated by the upward stroke of the wheel. Regulate the displacement of.

  According to the present invention, the restricting means for restricting the displacement of the bush caused by the downward stroke of the wheel from the displacement of the bush caused by the upward stroke of the wheel is provided. Bushing that occurs when the arm strokes can be controlled, and the stroke rigidity in the rebound direction of the suspension arm is increased without using a rebound spring as in the conventional device, and the piston rod of the shock absorber is Therefore, it is possible to prevent the bottom protrusion when it is in the most protruding state.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration in an embodiment of the present invention, in which 1 is a knuckle as a rotation support member that rotatably supports a wheel 2, and the upper and lower ends of the knuckle 1 are respectively A. A double wishbone type suspension is constituted by being rotatably connected to a vehicle body side member via an upper link 3 and a lower link 4 formed in a letter shape.

  The upper link 3 has an apex portion connected to the upper end of the knuckle 1 via a ball joint 5. Also, cylindrical connecting portions 6 are formed at the front end portion and the rear end portion on the opposite side, and bushes 8 are inserted into the through holes of these connecting portions 6 so as to be suspension members as vehicle body side members (not shown). It is configured to be slidably supported by a mounting bracket attached to the.

  On the other hand, the lower link 4 has an apex portion connected to the lower end of the knuckle 1 via a ball joint 10. Further, cylindrical connecting portions 12 are formed at the front end portion and the rear end portion on the opposite side, and bushes 20 are inserted into through holes of these connecting portions 12 so as to be attached to a suspension member (not shown). The bracket is configured to be slidably supported by the bracket.

Here, the connecting portions 6 and 12 are configured such that the bushes 8 and 20 are arranged vertically with their cylinder axes aligned with the vehicle vertical direction. Acts in a twisting direction with respect to the stroke. In other words, the upper link 3 and the lower link 4 can be swung in the vertical direction by the twisting of the bushes 8 and 20.
A cylinder tube 15a of the shock absorber 15 is rotatably attached to the central portion of the lower link 4, and the upper end of the piston rod of the shock absorber 15 is swingably attached to a vehicle body side member (not shown).

By the way, if the rigidity of the suspension in the rebound direction is low, when the wheel strokes in the rebound direction and the piston rod of the shock absorber extends to the cylinder, a so-called bottom-out occurs in which the piston collides with the cylinder. is there.
Therefore, in the present invention, a mechanism for increasing the rigidity (spring constant) in the rebound direction of the suspension is provided to prevent bottom thrust when the piston rod of the shock absorber is fully extended with respect to the cylinder.

The bush that supports the right wheel lower link will be described below.
2A and 2B are diagrams showing details of the bush 20 in the first embodiment, wherein FIG. 2A is a plan view and FIG. 2B is a cross-sectional view. The bush 20 is divided in two into a first bush 21 on the upper side in the axial direction and a second bush 22 on the lower side, and each bush 21 and 22 has inner cylinders 21a and 22a made of cylindrical metal members, Outer cylinders 21b and 22b made of a metal member formed at a distance from the outer side of the inner cylinder, and an elastic portion 21c made of a cylindrical elastic member that is vulcanized and bonded to the outer peripheral surface of the inner cylinder and the inner peripheral surface of the outer cylinder. , 22c.

And flange 21b ', 22b' is formed in the edge part outside the through-hole of the connection part 12 in each outer cylinder 21b, 22b, and the opposing edge part of each outer cylinder 21b, 22b is in a through-hole. It is comprised so that it may mutually contact | abut.
Further, the bush 20 is configured to restrict the twisting with respect to the downward stroke of the wheel 2, and the bushes 21 and 22 are formed with stoppers 21d and 22d as restricting means. The stoppers 21d and 22d are made of an elastic member such as rubber and are integrally formed with the bushes 21 and 22 by being vulcanized and bonded to the outer cylinder flanges 21b ′ and 22b ′.

Further, as shown in FIG. 2A, the stoppers 21d and 22d are arranged on the half circumferences of the outer cylinder flanges 21b ′ and 22b ′. The stoppers 21d and 22d are arranged at the corner positions.
Here, in this embodiment, in order to restrict the twisting of the wheel 2 with respect to the stroke in the rebound direction, the bushes 21 and 22 are arranged so that the stoppers 21d and 22d are arranged on the vehicle inner upper side and the vehicle outer lower side of the bush 20 respectively. Install.

Therefore, in order to attach the lower link 4 to the vehicle body side member, the first bush 21 is first press-fitted into the through hole of the connecting portion 12 from above, and the second bush 22 is press-fitted into the through hole from below. The opposite ends of the bushes 21 and 22 are brought into contact with each other in the hole. At this time, the outer cylinders 21b and 22b are fixed in the through hole of the connecting portion 12 by fitting or welding.
Next, a bolt is inserted into the central portion of the bush 20 and screwed and fastened to the mounting bracket 18 attached to the suspension member with a nut. Thereby, the lower link 4 is attached to the vehicle body side member. At this time, the stoppers 21 d and 22 d provided on the bush 20 come into contact with the axially opposed surface of the mounting bracket 18.

With such a configuration, for example, when the wheel 2 bounces, the vehicle outer side of the lower link 4 rises. At the vehicle inner end portion of the lower link 4, stoppers are not provided at the vehicle inner lower end portion and the vehicle outer upper end portion of the bush 20, so that there is some restriction depending on the rigidity of the bush 20 itself, but the twisting of the bush 20 is restricted. It will never be done.
On the other hand, when the wheel 2 rebounds, the vehicle outer side of the lower link 4 is lowered. At the vehicle inner end of the lower link 4, the stopper 20 d and 22 d provided at the vehicle inner upper end and the vehicle outer lower end of the bush 20 restrict the twisting of the bush 20, and restrict the downward movement of the lower link 4. Is done.

FIG. 3 compares the characteristics of the suspension when the suspension moves up and down, with and without a stopper for restricting the twisting of the bush supporting the lower link. In FIG. 3, a solid line indicates a case where a stopper is provided, and a broken line indicates a case where a stopper is not provided.
As is clear from this figure, it can be seen that when the stopper is provided, the rigidity can be made different between the bound direction and the rebound direction, and the displacement in the rebound direction can be limited. This is the same effect as when a rebound spring is provided on the shock absorber as in the conventional device.

The lower link 4 is provided in a pair on the left and right sides, and the bushes 20 that support the lower link 4 are symmetrical to each other on the left and right. In other words, the left and right bushes 20 are each provided with a stopper at the vehicle inner upper end and the vehicle outer lower end so as to restrict the twisting of the wheel in the rebound direction stroke.
Thus, in the first embodiment, since the stopper is provided at the vertical diagonal position in the bush that supports the lower link so that the lower link can swing with respect to the vertical stroke of the wheel, The rigidity in the bound direction and the rebound direction can be set to different characteristics.

In addition, stoppers are provided at the vehicle inner upper end and the vehicle outer lower end so as to restrict the stroke in the rebound direction of the suspension, so that the piston rod of the shock absorber attached to the lower link is in the most protruding state with respect to the cylinder. It is possible to prevent bottoming when it becomes.
Furthermore, since the bush that supports the lower link is arranged vertically so that the cylinder axis coincides with the vehicle vertical direction, the assembly of the suspension can be improved.
In addition, since the stopper for restricting the stroke in the rebound direction of the lower link is integrated with the bush, even when the insulator is bent in the direction perpendicular to the axis, it does not affect the rigidity during the vertical stroke of the suspension Can be.

Next, a second embodiment of the present invention will be described.
In the second embodiment, the lower link is supported by using a bush that is not divided into two parts in the axial direction, whereas the bushing that is divided into two parts in the axial direction is used in the first embodiment. It is what you do.
That is, as shown in FIG. 4 which is a detailed view of the bush 20 in the second embodiment, the bush 20 is formed at a distance from the inner cylinder 23a made of a cylindrical metal member and the outer side of the inner cylinder 23a. An outer cylinder 23b made of a metal member, and an elastic portion 23c made of a cylindrical elastic member that is vulcanized and bonded to the outer peripheral surface of the inner cylinder 23a and the inner peripheral surface of the outer cylinder 23b.

A flange 23b 'protruding outward in the radial direction is formed at the upper end of each outer cylinder 23b, and a flange 23b "protruding in the radial inward direction is formed at the other end. The bush 20 is not divided into two vertically in the axial direction like the bush 20 in the first embodiment described above, but is an integral object.
Further, the bush 20 is provided with stoppers 23d 'and 23d "for restricting the twisting with respect to a stroke in a certain direction of the wheel 2 at diagonally upper and lower positions of the bush 20. The stoppers 23d', 23d "" Is made of an elastic member such as rubber, and has an integral structure with the bush 20 by being vulcanized and bonded to the outer cylinder flanges 23b 'and 23b ".

Here, in the present embodiment, the bush 20 is attached so that the stoppers 23d ′ and 23d ″ are disposed on the vehicle inner upper side and the vehicle outer lower side of the bush 20 in order to restrict the twisting of the wheel 2 with respect to the stroke in the rebound direction. .
Therefore, in order to attach the lower link 4 to the vehicle body side member, first, the flange 23 ″ side protruding inward in the radial direction of the bush 20 is press-fitted from the upper side of the through hole of the connecting portion 12. At this time, the outer cylinder 23b is connected. It is fixed in the through hole of the portion 12 by fitting or welding.

Next, a bolt is inserted into the central portion of the bush 20 and screwed and fastened to the mounting bracket 18 attached to the suspension member with a nut. Thereby, the lower link 4 is attached to the vehicle body side member. At this time, the stoppers 23 d ′ and 23 d ″ provided on the bush 20 come into contact with the axially opposed surface of the mounting bracket 18.
With this configuration, as in the first embodiment described above, when the wheel 2 rebounds, the vehicle outer side of the lower link 4 is lowered, and the vehicle inner side of the bush 20 is at the vehicle inner end of the lower link 4. The stoppers 23d ′ and 23d ″ provided at the upper end portion and the vehicle outer lower end portion restrict the twisting of the bush 20 and restrict the lower link 4 from moving downward.

As described above, in the second embodiment, since the stopper is provided at the upper and lower diagonal positions of the bush that supports the lower link so as to be swingable with respect to the vertical stroke of the wheel, The rigidity with the rebound direction can have different characteristics.
In addition, a bush having a flange projecting radially outward at one end and a flange projecting radially inward at the other end is arranged vertically so that the cylinder shaft coincides with the vehicle vertical direction. When assembling, it is only necessary to press-fit the bush only from the upper side of the through-hole of the connecting portion, and there is no need to press-fit from above and below the through-hole of the connecting portion as in the case where the bush is divided into two parts. It can be improved further.

Next, a third embodiment of the present invention will be described.
In the third embodiment, the stopper is integrated with the bush in the first and second embodiments described above, but is integrated with the mating member that contacts the upper and lower ends of the bush. Is.
That is, as shown in FIG. 5 which is a detailed view of the bush 20 in the third embodiment, the bush 20 is formed at a distance from the inner cylinder 24a made of a cylindrical metal member and the outer side of the inner cylinder 24a. An outer cylinder 24b made of a metal member, and an elastic portion 24c made of a cylindrical elastic member that is vulcanized and bonded to the outer peripheral surface of the inner cylinder 24a and the inner peripheral surface of the outer cylinder 24b. It is assumed that the bush 20 in the present embodiment has no flange formed on the inner cylinder and the outer cylinder.

In addition, although this embodiment demonstrated the case where the flange was not formed in the inner party and the outer cylinder, it is not limited to this, The flange may be formed.
The mounting bracket 18 as a mating member that contacts the upper and lower ends of the bush 20 is provided with stoppers 18a ′ and 18a ″ for restricting the twisting with respect to the stroke of the wheel 2 in a certain direction. The stoppers 18a ′ and 18a ″ are configured so as to be disposed at diagonally upper and lower diagonal positions of the bush 20 during assembly. The stoppers 18a ′ and 18a ″ are made of an elastic member such as rubber, and are integrally formed with the mounting bracket 18 by being vulcanized and bonded to the axially opposed surface of the mounting bracket 18.

Here, in the present embodiment, the stoppers 18a ′ and 18a ″ are configured to be disposed on the vehicle inner upper side and the vehicle outer lower side of the bush 20 in order to restrict the twisting of the wheel 2 with respect to the stroke in the rebound direction.
Therefore, in order to attach the lower link 4 to the vehicle body side member, the bush 20 is first press-fitted from above the through hole of the connecting portion 12. At this time, the outer cylinder 24b is fixed in the through hole of the connecting portion 12 by fitting or welding.
Next, a bolt is inserted into the central portion of the bush 20 and screwed and fastened to the mounting bracket 18 attached to the suspension member with a nut. Thereby, the lower link 4 is attached to the vehicle body side member. At this time, the stoppers 18 a ′ and 18 a ″ provided on the mounting bracket 18 come into contact with the outer cylinder 24 b of the bush 20 and the connecting portion 12.

With such a configuration, as in the first and second embodiments described above, when the wheel 2 rebounds, the vehicle outer side of the lower link 4 is lowered, and the bush 20 is formed at the vehicle inner end portion of the lower link 4. The stoppers 18a 'and 18a "provided at the vehicle inner upper end and the vehicle outer lower end restrict the twisting of the bush 20 and restrict the lower link 4 from moving downward.
As described above, in the third embodiment, the mounting bracket for attaching the bush is provided with a stopper for restricting the twisting of the bush in a certain direction. Therefore, regardless of the shape of the bush, the bound direction and the rebound when the suspension moves up and down. The direction and the rigidity can be different characteristics.

Next, a fourth embodiment of the present invention will be described.
In the fourth embodiment, a receiving portion, which is one stopper member formed in an integral structure, is provided on the mating member that contacts the upper and lower ends of the bush, and the stiffness of the bush against the suspension stroke is effectively obtained. It is what I did.
That is, in the fourth embodiment, the bush 20 has the same configuration as that of the first embodiment described above, and as shown in FIG. 6, the other stopper 21d formed integrally with the bush 20 side in the vehicle vertical direction. The thickness is configured to be thicker in the direction in which the bush 20 is twisted and the outer side in the radial direction of the bush 20, and the mounting bracket 18 has a convex portion that comes into contact with the stopper 21 d on the bush 20 side. A receiving portion 18b (one stopper member) is provided. Here, FIG. 6A is a plan view of the mounting bracket 18, and FIG. 6B is a side view of the bush 20 and the mounting bracket 18.

The receiving portion 18b is formed by pressing or the like and includes an inclined portion 18b ′. When the bush 20 receives a twisting force with respect to the stroke of the wheel 2 in the rebound direction, the outer cylinder flanges 21b ′ and 22b ′ of the bush 20 and the inclined portion 18b ′ are configured to be parallel to each other.
In FIG. 6, the stopper 21d corresponds to the bush member-side stopper, and the receiving portion 18b corresponds to the counterpart member stopper.

FIG. 7 is a side view of the bush 20 and the mounting bracket 18 in the first embodiment described above. FIG. 7A is a state in which a twisting force is not applied to the bush 20, and FIG. 2 shows a state in which a twisting force is acting on the stroke in the rebound direction.
As is apparent from this figure, when the receiving portion is not formed on the mounting bracket 18 and the contact surface with the bush 20 is flat, the twisting direction is applied even when a twisting force is applied to the bush 20. It can be seen that the portion A extending in the radial direction orthogonal to the distance from the mounting bracket 18 does not change much and the compression rate of the stopper 21d is low. That is, the stopper 21d of the portion A is not a compression element at the time of prying.
Therefore, in this embodiment, the stopper of the portion A is also given a large rigidity in the twisting direction.

FIG. 8 is a side view of the bush 20 and the mounting bracket 18 in this embodiment. FIG. 8A is a state in which a twisting force is not acting on the bush 20, and FIG. 8B is a rebound direction of the wheel 2. This shows a state in which a twisting force is acting on the stroke.
As is apparent from this figure, by forming the receiving portion 18b on the mounting bracket 18, the thickness of the stopper 21d gradually decreases toward the portion B extending in the radial direction perpendicular to the twisting direction. As a result, when a twisting force is applied to the bush 20, the compression rate of the stopper 21d of the elastic center portion B can be increased, so that more elastic members can be used as compression elements when the bush 20 is twisted. .

  Thus, in the fourth embodiment, the thickness of the stopper is in the direction of the bushing and the outer side in the radial direction of the bush is thickened, that is, the thickness of the stopper is directed toward the center of the bushing. Since the mounting bracket is provided so as to be thin, when the bushing receives a twisting force against the vertical stroke of the wheel, the stopper in the portion near the center against the twisting also has a rigidity in the twisting direction. Since it can be made large and more elastic members can be used as compression elements, it is possible to effectively regulate the twisting of the bush.

Further, since the end face of the bush and the receiving portion are configured to be parallel when a twisting force is applied to the bush, the bushing can be more effectively regulated.
In the fourth embodiment, the thickness of the stopper on the bushing side is perpendicular to the prying direction by providing the mounting bracket as a mating member that contacts the upper and lower ends of the bushing with a convex portion that is a stopper member. However, the present invention is not limited to this, and the projection is formed on the flange on the bush side to form an elastic body on the mating bracket. This stopper may be provided, and the thickness of the stopper may be reduced toward the portion extending in the radial direction perpendicular to the prying direction.

In the fourth embodiment, the case where the receiving portion is parallel to the member facing the receiving portion when a twisting force is applied to the bush has been described. However, the present invention is not limited to this. Instead, it may be substantially parallel.
Further, in the fourth embodiment, the case where the configuration of the bush is the same as that of the first embodiment has been described. However, the present invention is not limited to this, and the second or third embodiment described above. You may make it be the same structure as the bush in a form.

In each of the above embodiments, the case where the rubber member is applied to the stopper has been described. However, the present invention is not limited to this, and a coil spring, a leaf spring, or the like may be applied.
In each of the above embodiments, the case where the present invention is applied to the bush supporting the lower link of the double wishbone type suspension has been described. However, the present invention is not limited to this. It may be a suspension.

  Further, in each of the above embodiments, the case where the present invention is applied to the vehicle body side attachment point of the lower link has been described. However, the present invention is not limited to this, and is applied to the vehicle body side attachment point of the trailing arm. You can also. For example, when the present invention is applied to the mounting point (front end portion) of the trailing arm on the vehicle body side, the bush is twisted against the stroke in the rebound direction of the wheel by providing stoppers at the vehicle front upper end portion and the vehicle rear lower end portion. Can be regulated.

It is a schematic structure figure showing an embodiment of the present invention. It is a block diagram which shows the detail of the bush in 1st Embodiment. It is a figure explaining the effect of this invention. It is a block diagram which shows the detail of the bush in 2nd Embodiment. It is a block diagram which shows the detail of the bush in 3rd Embodiment. It is a block diagram which shows the detail of the bush in 4th Embodiment. It is a figure explaining the torsional rigidity of the bush in a 1st embodiment. It is a figure explaining the torsional rigidity of the bush in 4th Embodiment.

Explanation of symbols

2 Wheel 3 Upper link 4 Lower link 10 Ball joint 12 Connection 15 Shock absorber 18 Mounting bracket 20 Bushing 21a, 22a Inner cylinder 21b, 22b Outer cylinder 21c, 22c Elastic part 21d, 22d Stopper

Claims (7)

In the suspension arm support structure in which one end of the suspension arm is connected to the vehicle body via a cylindrical bush member so as to be able to swing with respect to the vertical stroke of the wheel,
A suspension arm support structure, comprising: a restricting means for restricting the displacement of the bush member caused by the downward stroke of the wheel from the displacement of the bush member caused by the upward stroke of the wheel.   The bush member is composed of an inner cylinder that inserts a side portion of the vehicle body, an outer cylinder that houses the inner cylinder, and an elastic member that is interposed between the inner cylinder and the outer cylinder. The cylinder shaft is disposed in the vertical direction of the vehicle, and the restricting means is a stopper member configured to restrict the twisting of the bush member that is generated by the stroke of the suspension arm accompanying the downward stroke of the wheel. The suspension arm support structure according to claim 1.   The suspension arm support structure according to claim 2, wherein the stopper member is integrated with the bush member.   The suspension arm support structure according to claim 2, wherein the stopper member is integrally formed with a mating member facing the upper and lower ends of the bush member.   The said stopper member is comprised by the bush member side stopper formed with the said bush member by integral structure, and the other party member stopper formed by the said counterpart member by integral structure. 3. The suspension arm support structure according to 2.   The suspension arm according to any one of claims 2 to 5, wherein the stopper member is configured to be thicker in a twisting direction of the bush member and on a radially outer side of the bush member. Support structure.   An end surface of the stopper member, which is formed integrally with the counterpart member, is opposed to the end surface of the bush member when a twisting force due to a downward stroke of the wheel is applied to the bush member. The suspension arm support structure according to any one of claims 4 to 6, wherein the suspension arm support structure is configured to be parallel or substantially parallel to each other.

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