JPS641126Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bushing used for connection parts of suspension members of vehicles such as automobiles, and more particularly to a bushing configured to variably control spring characteristics.

In the suspension of a vehicle such as an automobile, in order to suppress the transmission of vibration from the suspension member through the vehicle body and into the passenger compartment when the vehicle is running, there is a A vibration-proof rubber bushing is incorporated that allows for small relative displacements and damps vibrations. It is desirable that such bushings have high rigidity in order to improve the vehicle's handling stability and high-speed straight-line performance, as well as to reduce nose dive, stiffness when starting, and vibration when starting. From the point of view of improving ride comfort and quietness in the vehicle interior, it is desirable that the rigidity is low and the compliance is high.
In order to meet these demands, it is possible to make the spring characteristics of the bush nonlinear or to give directionality to the stiffness of the bush by appropriately selecting the shape of the bush or embedding a metal insert in the bush. This has been done traditionally.

However, conventional bushings are entirely composed of a solid rubber-like elastic body, and once the shape etc. of the bushing is specified, its spring characteristics are also uniquely determined. cannot respond to For example, if the stiffness of the bushings is increased with emphasis on vehicle handling stability, the ride comfort of the vehicle will deteriorate, and conversely, if the stiffness of the bushings is reduced with emphasis on vehicle ride comfort, the vehicle handling stability etc. will deteriorate. In order to change the spring characteristics of the bushing, the bushing must be replaced with another bushing of different rigidity or shape.

For example, as described in Japanese Utility Model Application Publication No. 57-98909, an inner cylinder and an outer cylinder are arranged substantially concentrically with respect to one axis, and an inner cylinder and an outer cylinder are interposed between these and are opposed to each other with respect to the axis. A bushing assembly consisting of a rubber-like elastic bushing having two chamber spaces at one position, and configured to change the relative position of the inner and outer cylinders by selectively supplying hydraulic pressure to the two chamber spaces. Bushing assemblies are already known. However, in such a bushing assembly, since the chamber spaces are provided at positions facing each other with respect to the axis, the direction in which the rigidity of the bush and the relative position of the inner and outer cylinders can be changed is in the direction connecting the two chamber spaces. The rigidity of the bushing and the relative position of the inner and outer cylinders cannot be changed in other directions.

In view of the above-mentioned problems with conventional bushings used in connection parts of suspension parts of vehicles such as automobiles, the present invention has been developed to allow the bushings to be adjusted according to the driving conditions of the vehicle without replacing the bushings. The purpose of the present invention is to provide an improved bushing in which the spring characteristics can be arbitrarily controlled and the rigidity of the bushing and the relative position of the inner and outer cylinders can be changed in directions other than the direction connecting the axis and the chamber space. It is said that

According to the present invention, this object is achieved by a rubber-like elastic bushing interposed between an inner cylinder and an outer cylinder which are arranged substantially concentrically with respect to one axis, and which are arranged substantially concentrically with respect to one axis. It has at least one set of chamber spaces provided in non-opposing positions, each chamber space being communicated with the outside through passage means independently of each other, and configured to introduce controlled fluid pressure into the bush. achieved.

According to this configuration, by changing the pressure of the fluid introduced into the chamber space through the passage means, the rigidity of the bushing can be changed as appropriate even when the vehicle is running. By lowering the pressure and reducing the stiffness of the bush,
It can improve the ride comfort of the vehicle,
Conversely, by increasing the fluid pressure in the room space and increasing the rigidity of the bushing, it is possible to improve the maneuverability of the vehicle.

Furthermore, since the bushing according to the present invention has at least one set of chamber spaces provided at positions that do not face each other with respect to the axis, the combination of chamber spaces into which high or low pressure fluid pressure is introduced and the pressure relationship between them can be adjusted as appropriate. If selected, it is possible to selectively change the stiffness in directions other than the direction connecting the axis and the chamber space, and also change the relative position of the inner and outer cylinders in directions other than the direction connecting the axis and the chamber space. The alignment and geometry of the suspension components can be varied over a wide range.

In addition, in the bushing according to the present invention, the number of chamber spaces may be any number, but two sets of chamber spaces are provided at positions not facing each other with respect to the axis, and one set of chamber spaces is provided. Preferably, each of the chamber spaces is arranged such that one chamber space faces one of the other set of chamber spaces, and the other of one set of room spaces faces the other of the other set of room spaces. Further, in this case, it is preferable that the two sets of chamber spaces, that is, the four chamber spaces, are arranged around the axis so as to be equally spaced from each other. With this configuration, the stiffness of the bushing can be selectively changed in substantially any direction perpendicular to the axis, and the relative positions of the inner and outer cylinders can be changed.

In the bush according to the present invention, the fluid introduced into the chamber space may be either a compressible fluid such as air or an incompressible fluid such as oil, but it is preferable that the fluid is a compressible fluid. In some cases, the spring characteristics of the bushing can be changed to significantly nonlinear spring characteristics by simply cutting off the communication between the chamber space and the fluid supply source without changing the fluid pressure within the chamber space. When the fluid introduced into the chamber space is an incompressible fluid, the bushing is compressed due to the flow resistance generated when the fluid in the chamber space is moved in and out of the chamber space through the passage means due to the elastic deformation of the bushing. Since high frequency vibrations input to the bushing are attenuated, transmission of high frequency vibrations to the body etc. via the bush can be suppressed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a longitudinal cross-sectional view showing one embodiment of the bush according to the present invention, which is integrally constructed with an inner cylinder and an outer cylinder as a bush assembly, and FIG. 2 is a cross-sectional view taken along the line - in FIG. 1. . In these figures, 1 and 2 indicate an inner cylinder and an outer cylinder, respectively, which are arranged concentrically with respect to the axis 3. A flange portion 4 is provided at one end of the outer cylinder 2 to ensure accurate positioning of the bushing assembly relative to the sleeve when the bushing assembly is fitted into the sleeve provided at the end of the control arm or the like. There is. A bush 5 according to the present invention is interposed between the inner cylinder 1 and the outer cylinder 2. The bush 5 is made of anti-vibration rubber, and has an inner circumferential surface 6 and an outer circumferential surface 7, an outer circumferential surface 8 of the inner tube 1 and an inner circumferential surface 9 of the outer tube 2, respectively.
It is fixed by vulcanization adhesive or press fit.

Embedded within the bush 5 are four telescopic hollow bags 10 extending along the axis 3 at equally spaced positions around the axis 3. Four chamber spaces 11 are defined which are equally spaced around and extend along the axis 3. Thus, a pair of adjacent chamber spaces are located at positions that do not face each other with respect to the axis, but one chamber space of one group faces one chamber space of the other group, and the other chamber space of one group The chamber space of is opposite to the other chamber space of the other set. Each hollow bag 10 is fixed at one end to one end of a base 12 also buried in the bush 5 by a clamp 13, and each chamber space 11 is communicated with the outside of the bush 5 by the base 12. One end of a hose 15 is connected and fixed to the other end of the mouthpiece 12 by a clamp 14 . Although the other end of each hose 15 is not shown in the figure, it is connected to a compressed air supply source via a pressure control valve, etc., so that each room space 1
Controlled air pressure can be introduced into the chamber. The hollow bag 10 can be buried in the bush 5 by filling the hollow bag with oil or the like, placing it at a predetermined position in a mold for molding the bush, and molding the bush in a cast-in type. May be achieved.

Thus, according to the illustrated embodiment, each chamber space 11
By changing the air pressure inside the bushing, the stiffness of the bushing can be changed steplessly, and thereby the stiffness of the bushing can be changed as appropriate depending on the driving conditions of the vehicle. In particular, in the illustrated embodiment, there are four chambers equally spaced around the axis 3, so that the fluid in adjacent chambers or in two radially opposite chambers is By selectively changing the pressure, it is possible to selectively change the stiffness in any direction perpendicular to the axis of the bushing, such as in the longitudinal direction of the vehicle, in the vertical direction, or in a direction crossing these directions, and Since the position of the inner tube 1 with respect to the outer tube 2 can be changed in any direction perpendicular to the axis 3, the alignment and geometry of the members constituting the suspension can be changed as desired.

FIG. 3 is a cross-sectional view similar to FIG. 1, showing another embodiment of the bushing according to the present invention; FIG.
3 and 4 are sectional views taken along line 3 of the figure. In Figs. 3 and 4, the same reference numerals are used to designate parts which are substantially the same as those shown in Figs. 1 and 2.

In this embodiment, the bushing 5 has a first portion 16 fixed to the outer circumferential surface 8 of the inner cylinder 1 at the inner circumferential surface 6 by vulcanization adhesive or press fit, and a first portion 16 fixed to the outer circumferential surface 8 of the inner cylinder 1 at the outer circumferential surface 7.
and a second portion 17 fixed to the inner circumferential surface 9 by vulcanization adhesion or press fitting, and the first and second portions are bonded to each other at joint surfaces 18 and 19. Joint surfaces 18 and 19 each have an axis 3
four grooves 20 and 2 having a semicircular cross section and extending along the axis 3 at equally spaced positions around the
1 are formed, and these grooves cooperate with each other to define four chamber spaces 22 which are equally spaced around the axis 3 and which extend along it. Each chamber space 22 is communicated with the outside of the bush 5 through a base 12 embedded within the bush 5. This embodiment is otherwise constructed and adapted to function similarly to the embodiment shown in FIGS. 1 and 2.

FIG. 5 is a sectional view similar to FIGS. 1 and 3, showing still another embodiment of the bushing according to the present invention, and FIG. 6 is a sectional view taken along the line - in FIG. 5. In FIGS. 5 and 6, parts that are substantially the same as those shown in FIGS. 1 to 4 are given the same reference numerals.

In this embodiment, each chamber space 23 is defined by four grooves 24 having a U-shaped cross section and extending along the axis 3 and formed in the outer circumferential surface 7 of the bush 5 and the outer circumferential surface 9 of the outer cylinder 2. has been done. Furthermore, four grooves 25 are formed on the outer peripheral surface 7 of the bush 5 in alignment with the grooves 24, and the grooves 25 and the outer cylinder 2 form four passages 26 that communicate with the chamber space 23 at one end. There is. The other end of each passage 26 communicates with a hole 28 formed in a cylindrical part 27 formed integrally with the flange part 4, and each chamber space 23 is connected to the outside of the bush 5 by these passages 26 and holes 28. It is communicated.
The cylindrical part 27 has a cap 1 at a position aligned with the hole 28.
2 is fixed by welding. This embodiment is otherwise constructed and adapted to function similarly to the embodiment shown in FIGS. 1-4. In this embodiment, the chamber space 23 is located between the inner peripheral surface 6 of the bush 5 and the inner cylinder 1.
It may be formed between the outer circumferential surface 8 of.

Although the present invention has been described above in detail with reference to several embodiments, the present invention is not limited to these embodiments, and various embodiments are possible within the scope of the present invention. This will be clear to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing one embodiment of the bushing according to the present invention, and FIG. 2 is a line taken along the line of FIG.
FIG. 3 is a sectional view similar to FIG. 1 showing another embodiment of the bushing according to the present invention, FIG. 4 is a sectional view taken along the line - of FIG. 3, and FIG. FIG. 6 is a sectional view taken along the line - in FIG. 5, and FIG. 6 is a sectional view similar to FIGS. 1... Inner cylinder, 2... Outer cylinder, 3... Axis line, 4...
Flange part, 5...button, 6...inner peripheral surface,
7, 8... Outer peripheral surface, 9... Inner circumferential surface, 10... Hollow bag, 11... Chamber space, 12... Cap, 13, 1
4... Clamp, 15... Hose, 16... First part, 17... Second part, 18, 19... Joint surface, 20, 21... Groove, 22, 23... Chamber space, 24 , 25... groove, 26... passage, 27...
Cylindrical part, 28... hole.

Claims (1)

[Scope of utility model registration request] At least one pair of rubber-like elastic bushings interposed between an inner cylinder and an outer cylinder arranged substantially concentrically with respect to one axis, and provided at positions not facing each other with respect to the axis. It has a room space of
A bushing configured such that each chamber space is communicated with the outside through passage means independently of each other, and a controlled fluid pressure is introduced thereinto.