JPH08210420A - Mounting structure of strut mount - Google Patents

Abstract

PURPOSE: To suppress the enlargement of the spring constant in the wrench direction of a strut mount by constituting an elastic body interposed between the top of a rod and a tower part out of a lower elastic body whose inside periphery is coupled with the top of the rod and whose outside periphery is coupled with the side of the tower part, and an upper elastic body whose outside periphery is coupled with the side of the tower part. CONSTITUTION: In the top mounting structure of a strut type suspension device for an automobile, the tubular lower inner cylinder 31 is sandwiched and fitted between the end plate 41 and the top end plate 21a, with its top end part fixed to the rod 61 of a shock absorber through an end plate 41, and also with its bottom end part fixed to the top plate 21a of the bumper rubber 21 of a shock absorber. The device is provided with a tubular lower outside cylinder 32a and an upper outside cylinder 32b, and these are made in taper shape, and both are welded to a connection member 33, whereby they are integrated. Moreover, the upper inside cylinder 34 is placed on a circular elastic body 37, with its bottom end face attached to the end plate 41, and an upper elastic body 36 is bonded by baking or the like to the outside periphery of the upper inside cylinder 34 and the inside periphery of the upper outside cylinder 32b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strut mount mounting structure applied to a strut suspension of a vehicle, an actuator portion of an active suspension, or the like.

[0002]

One of the features of strut mounts is that the spring constant can be reduced, and they are widely used in strut suspensions for vehicles such as automobiles. As a strut suspension for an automobile of this type, one disclosed in Japanese Patent Laid-Open No. 3-28541 has been conventionally provided, and the main structure of this is shown in FIG.

In FIG. 3, 50 is a strut mount, 2 is a tower portion standing on the wheel house inner, 3 and 4 are upper support members and lower support members fixed to the upper side of the tower portion 2, 6 Is a shock absorber, 21 is a bumper bar of the shock absorber 6, and 20 is a coil spring. A seat plate 7 and a bottom of an inner cylinder 8 having a bottomed cylindrical shape are fixed to the upper end of the shock absorber 6 by a nut 9.

Reference numeral 10 is an outer cylinder provided outside the inner cylinder 8 with a constant space, and a peripheral edge of the outer cylinder 10 is a bolt 13.
It is fixed to the lower support member 4 by C and nuts 23, and is also fixed to the upper support member 3 by welding.

An elastic body 11 for absorbing vibration is interposed between the outer periphery of the inner cylinder 8 and the inner periphery of the outer cylinder 10, and the inner cylinder 8 and the outer cylinder 10 are separated by the elastic body 11. It is integrally connected.

According to the structure of the prior art, the upper end portion of the tower portion 2 of the wheel house inner 1 supporting the upper mounting portion 5 of the strut suspension is vertically moved by the upper support member 3 and the lower support member 4. Since it has a double structure, great rigidity can be obtained.

Since the upper flange 12a and the lower flange 12b having different height positions are formed on the outer cylinder 8 and fastened to the upper support member 3 and the lower support member 4, respectively, both support members 3 having a double structure are formed. The four opening edges can be connected via the mounting flange 12, and the rigidity can be further enhanced.

Further, an upper support member in which the bending moment transmitted from the input point to the outer cylinder 10 through the seat plate 7, the inner cylinder 8 and the elastic body 11 is arranged at the upper end of the shock absorber 6 with a vertical space. Since it is supported at two points, 3 and the lower support member 4, a large bending rigidity can be obtained.

[0009]

However, in the conventional strut-type suspension device mounting structure, since the inner cylinder 8 and the outer cylinder 10 are connected by the single elastic body 11, the structure shown in FIG. As shown in FIG. 2, when the outer diameter of the strut mount 50 is reduced and the size is reduced, the torsional spring constant B1 sharply increases as compared with the axial spring constant A.

For this reason, friction of the actuator sliding portion of the shock absorber 6 and the suspension as a whole is increased, which leads to deterioration of riding comfort and steering stability of the vehicle and deterioration of durability. If the outer diameter of the strut mount is increased in order to prevent such a problem, the strut mount becomes large, which leads to an increase in the size and cost of the entire strut suspension system.

An object of the present invention is to suppress an increase in the outer diameter of the strut mount, suppress an increase in the torsional spring constant of the strut mount, and secure a required value for the axial spring constant, so that the entire suspension is secured. To reduce the friction of the vehicle to improve the riding comfort, steering stability and durability of the vehicle, and to reduce the strut mount outer diameter to reduce the size and cost of the strut mount. It is to be realized.

[0012]

According to the present invention, an elastic body is provided between the upper end of a rod of a shock absorber or a hydraulic actuator extending above a suspension suspension of a vehicle and the tower portion of a wheel house inner. In the strut mount mounting structure of the suspension device, the elastic body is arranged on the inner peripheral side of the rod upper end and the outer peripheral side of the lower elastic body connected to the tower portion side, and on the upper surface side of the lower elastic body. The outer peripheral side has an upper and lower double structure composed of an upper elastic body connected to the tower portion side.

In this case, the upper elastic body is arranged such that the lower elastic body has a predetermined degree of freedom in the twisting direction and the axial pushing of the lower elastic body can be transmitted to the upper elastic body. The specific arrangement structure of such a configuration is, for example, that the lower elastic body and the upper elastic body are arranged vertically with a predetermined gap therebetween, and that the lower elastic body is connected via a mounting portion of a rod connected to the lower elastic body. It is preferable that the lower elastic body and the upper elastic body are arranged so as to be axially contactable with each other. The specific structure of such an elastic body is such that the lower elastic body and the upper elastic body are each formed into a ring circle having an inner cylinder and an outer cylinder, and the outer cylinders of both elastic bodies are bridged. It is preferable that the upper end of the rod is fixed to the inner cylinder of the lower elastic body via the mounting portion and is fixed to the tower portion so that the mounting portion can contact the lower end of the inner cylinder of the upper elastic body. .

[0014]

According to this invention, the elastic body is arranged on the lower elastic body connected between the rod and the tower portion, and is arranged on the upper surface side of the lower elastic body, and the outer peripheral side is connected to the tower portion side. Since the upper and lower elastic bodies have a double-upper structure, the torsion in the twisting direction transmitted by the rod is absorbed only by the lower elastic body, and the axial oscillation includes the upper elastic body and the lower elastic body. It can be configured to absorb by two elastic bodies. Therefore, in the axial direction, the same spring load as in the case of one conventional elastic body can be secured, and in the prying direction, only the lower elastic body is displaced in the prying direction,
The spring load can be suppressed low. In this case, it is preferable that the thickness of the lower elastic body in the vertical direction be smaller than the thickness of the upper elastic body so that the spring constant in the twisting direction can be further reduced.

In order to smoothly perform such an action, the lower elastic body has a predetermined degree of freedom in the twisting direction, and the axial pushing of the lower elastic body can be transmitted to the upper elastic body. It is preferable to dispose the upper elastic body, and specifically, to contact the lower elastic body on the shock absorber (hydraulic actuator) side where vibration occurs and the upper elastic body. The lower elastic body and the upper elastic body are brought into axial contact with each other through a mounting portion of a rod connected to the body, and a predetermined gap is provided between the lower elastic body and the upper elastic body around the lower elastic body and the upper elastic body so as to have a degree of freedom in the twisting direction. It arranges via and is constituted.

To explain the action of such an elastic body more concretely, for example, the elastic body is formed into a ring-shaped cross section having an inner cylinder and an outer cylinder for the lower elastic body and the upper elastic body, respectively. At the same time, the outer cylinders of both elastic bodies are fixed to the tower portion so as to extend between the outer cylinders, while the upper end of the rod is fixedly mounted on the inner cylinder of the lower elastic body via the mounting portion, and the mounting portion is the upper elastic body. When the axial force from the shock absorber (hydraulic actuator) side acts on the lower inner cylinder, the force can be transmitted to the upper inner cylinder as well, so that it can contact the lower end of the inner cylinder. The displacement is absorbed by both the lower elastic body and the upper elastic body, and is supported by the outer cylinder.
On the other hand, when a force (moment) in the prying direction from the shock absorber side acts on the lower inner cylinder, this force is not transmitted to the upper inner cylinder, and the displacement in the prying direction due to this force is absorbed only by the lower elastic body, It is supported by an outer cylinder.

Therefore, since the axial displacement is absorbed by both the lower and upper elastic bodies, if the combined spring constants of the lower and upper elastic bodies are made the same as those of the conventional one, the same degree of axial movement as that of the conventional one is obtained. A directional vibration damping action is obtained. On the other hand, since the displacement in the prying direction is absorbed only by the lower elastic body, if the axial spring constant that combines the lower and upper elastic bodies is set to the same as the conventional one as described above, the prying of only the lower elastic body will occur. The spring constant in the direction becomes much smaller.

Therefore, even if the outer diameter of the strut mount is reduced, the rate of increase of the spring constant in the twisting direction is small, so that it is possible to reduce the outer diameter of the strut mount, and it is possible to realize the miniaturization of the suspension device. it can.

[0019]

Embodiments of the present invention will now be described in detail with reference to FIGS. However, the dimensions, materials, shapes, relative positions, etc., of the components described in this embodiment are not intended to limit the scope of the present invention thereto, unless there is a specific description, and are merely illustrative examples. Nothing more than.

FIG. 1 shows the details of the upper mounting structure of an automobile strut suspension according to an embodiment of the present invention. In the figure, 31 is a lower inner cylinder formed in a cylindrical shape, and the upper end is a shock. The bolt 6 is fixed to the rod 61 of the absorber 6 (see FIG. 3) via the end plate 41, and the lower end is fixed to the upper end plate 21a of the bumper bar 21 of the shock absorber 6 by the bolt 42. The lower inner cylinder 31 is clamped and fixed between the end plate 41 and the upper end plate 21a of the bumper bar 21.

Reference numeral 32a denotes a lower outer cylinder formed in a cylindrical shape, 32
Reference numeral b denotes an upper outer cylinder, and as shown in FIG. 1, these are formed in a tapered shape such that their diameters decrease upward. The lower outer cylinder 32a and the upper outer cylinder 32b are welded and integrated with the connecting member 33 to form the outer cylinder 32. The flange 33a on the outer periphery of the connecting member 33 is fixed to the upper surface of the tower 2 (see FIG. 1) with bolts 38.

Reference numeral 34 denotes an upper inner cylinder, which is the lower inner cylinder 31.
And a lower end surface thereof is attached to the end plate 41 of the lower inner cylinder 31 and placed on an annular elastic body 37 made of a flexible material such as rubber or rubber. There is. As a result, the shock absorber (actuator) rod 6
The axial up and down movement of 1 is transmitted to the upper inner cylinder 34 via the lower inner cylinder 31, the end plate 41, and the elastic body 37, and the lower elastic body 3
5 and the upper elastic member 36 integrally function as an axial absorber. The contact between the lower inner cylinder 31 and the upper inner cylinder 34 via the annular elastic body 37 is elastic contact on the center side of the lower elastic body, and the lower elastic body 35 and the upper elastic body 3 around the elastic contact.
Since 6 are opposed to each other via the ring-shaped gaps 35/36, swinging of the lower elastic body 35 around the upper end of the actuator rod 61 in the prying direction is guaranteed.

The outer peripheral surface of the lower inner cylinder 31 and the lower outer cylinder 3
A lower elastic body 35 made of a flexible material such as rubber or rubber is adhered to the inner peripheral surface of 2a by means such as baking. The lower elastic body 35 has a lower spring constant than the upper elastic body 36, which will be described later, so that the spring constant of the lower elastic body 35 is set small.

An upper elastic member 36 is made of a flexible material such as rubber or rubber, and is adhered to the outer peripheral surface of the upper inner cylinder 34 and the inner peripheral surface of the upper outer cylinder 32b by means such as baking. . The upper elastic body 36, as described above,
It cooperates with the lower elastic body 35 to cope with an axial load from the shock absorber side.

When a vehicle equipped with the strut type suspension device constructed as described above is running, when the force in the direction of twisting due to the moment M from the shock absorber 6 side acts on the lower inner cylinder 31, the lower elastic body at the lower part is Only 35 is displaced in the twisting direction, and the lower upper elastic body 36 is not displaced.

Further, the axial displacement of the lower inner cylinder 31 due to the axial force F from the shock absorber side is transmitted to the upper inner cylinder 34 via the elastic body 37, and the upper elastic body 3 on the upper side.
It is absorbed by the axial displacement of 6. The displacement due to the axial force F is also absorbed by the displacement of the lower elastic body 35.

Therefore, in this embodiment, the displacement in the twisting direction is absorbed only by the lower elastic body 35, and the displacement in the axial direction is absorbed by both the upper elastic body 36 and the lower elastic body 35.

Therefore, if the axial synthetic spring constants (A in FIG. 2) of the lower and upper elastic bodies 35, 36 are set to be the same as those of the conventional one, the vibration damping action in the axial direction is approximately the same as that of the conventional one. In addition, since the displacement due to the force in the prying direction is absorbed only by the lower elastic body 35, the spring constant in the prying direction (B2 in FIG. 2) becomes significantly smaller than that of the conventional one.

Therefore, as shown in FIG. 2, the spring constant B2 in the twisting direction is significantly smaller than that of the conventional one even if the outer diameter of the strut mount is reduced, and the outer constant of the strut mount is reduced. The diameter can be reduced significantly.

[0030]

According to the present invention, the axial displacement due to the axial force from the rod side is absorbed by both the lower elastic body and the upper elastic body, and is supported by the upper and lower outer cylinders fixed to the tower portion. It

On the other hand, the displacement due to the moment in the twisting direction from the rod side is absorbed only by the lower elastic body, and the upper elastic body does not participate.

Therefore, if the axial spring constant obtained by combining the lower and upper elastic bodies is kept at the same value as that of the conventional one, the torsional spring constant of only the lower elastic body is much smaller than that of the conventional one. Therefore, even if the outer diameter of the strut mount is made small, the rate of increase in the spring constant in the torsion direction becomes small.

As a result, the outer diameter of the strut mount can be greatly reduced compared to the conventional one, and even if the strut mount is made compact and compact, the riding comfort, steering stability and durability of the vehicle are not deteriorated. Therefore, while maintaining good riding comfort and maneuverability of the vehicle and maintaining high durability,
It is possible to obtain a strut mount device that is small in size and low in cost.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a vehicle strut suspension system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a spring constant of the strut mount.

FIG. 3 is a cross-sectional view of a main part of a conventional strut suspension system.

[Explanation of symbols]

 2 tower part 6 shock absorber 31 lower inner cylinder 32 outer cylinder 32a lower outer cylinder 32b upper outer cylinder 34 upper inner cylinder 35 lower elastic body 36 upper elastic body 35/36 ring-shaped void 37 third elastic body 41 end plate 50 strut Mount 61 rod

Claims (5)

[Claims] 1. A structure for mounting a strut mount of a suspension system in which an elastic body is interposed between a rod upper end of a shock absorber or a hydraulic actuator extending above a suspension suspension system of a vehicle and a tower section of a wheel house inner. In the elastic body, the inner peripheral side is arranged at the rod upper end and the outer peripheral side is connected to the tower portion side, and the elastic body is arranged on the upper surface side of the lower elastic body, and the outer peripheral side is arranged at the tower portion side. Strut mount mounting structure characterized by an upper and lower double structure consisting of an upper elastic body connected to the 2. The upper elastic body is arranged so that the lower elastic body has a predetermined degree of freedom in the twisting direction and the axial pushing of the lower elastic body can be transmitted to the upper elastic body. Strut mount mounting structure according to claim 1. 3. The lower elastic body and the upper elastic body are arranged one above the other through a predetermined gap, and the lower elastic body and the upper elastic body are provided with shafts through a mounting portion of a rod connected to the lower elastic body. The strut mount mounting structure according to claim 2, wherein the strut mount mounting structure is arranged so as to be capable of contacting in a direction. 4. The mounting structure for a strut mount according to claim 1, wherein the thickness of the lower elastic body in the vertical direction is smaller than the thickness of the upper elastic body. 5. The lower elastic body and the upper elastic body are formed in a ring-shaped cross section having an inner cylinder and an outer cylinder, respectively,
It is fixed to the tower part as if the outer cylinders of both elastic bodies are installed between the outer cylinders, and the upper end of the rod is fixed to the inner cylinder of the lower elastic body via a mounting portion, and the mounting portion is inside the upper elastic body. The strut mount mounting structure according to claim 1, wherein the strut mount is configured so as to be capable of abutting against the lower end of the cylinder.