JPH0986125A - Strut type suspension device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce steering force by providing a coil spring in parallel with a strut on the outside in the car width direction against the strut and so that a spring central axis passes a connecting point of a wheel supporting member and a lower link and installing a bearing for strut rotation on an upper part of the coil spring. SOLUTION: A coil spring 12 to support car body weight is arranged in parallel on the outside in the car width direction against a strut 5, and an upper end of the coil spring 12 is supported on a car body side member 14 through a bearing 13. Consequently, it is possible to arrange the coil spring 12 without influencing upon a clearance D between the strut 5 and and a front wheel 2. Simultaneously, it is possible to reduce an inclination θk of a king pin axis Lk connecting a center of the coil spring 12 and the bearing 13 and a connecting point of a knuckle 1 and a lower link 4, and it is possible to reduce steering force at the time of steering the front wheel 2 by a steering mechanism at the time of turning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strut type suspension device in which a wheel supporting member is supported by struts, coil springs, lower links and struts.

[0002]

2. Description of the Related Art As a conventional strut type suspension device, for example, JP-A-61-200171 (hereinafter referred to as a first conventional example) and JP-A-2-225116 (hereinafter referred to as a second conventional example) are known. The ones described in are known. In the first conventional example, in a strut upper mount structure in which an upper end of a strut having a suspension spring is attached to a vehicle body via a bearing, a configuration in which the center of the bearing is offset laterally outward from a center point of the upper end attachment of the strut is disclosed. Has been done. According to the first conventional example, by adopting the above configuration, even if the upper end mounting center point of the strut is determined so that the strut does not interfere with the wheel, the inclination angle of the kingpin axis can be made small and the steering force can be reduced. In addition, since the center point of the upper end of the strut relating to the outer front wheel moves to the rear of the vehicle body during turning and strengthens the rear tilt of the strut, it is possible to keep the depression of the outer front wheel during braking and keep the clasp small. In addition, it can greatly contribute to the improvement of maneuverability and stability.

In the second conventional example, the upper end of a strut body having an oil damper inserted in the coil spring is rotatably supported by the vehicle body via a rotating portion formed in the portion, and the lower end is supported by an axle. In a strut-type front wheel suspension device for an automobile, which is fixed to one end of a partial racket, and the other end of the partial racket is rotatably connected to a lower arm,
A configuration is disclosed in which the coil spring and the oil damper of the strut body are offset to the inside of the vehicle with respect to the rotating portion, or the strut body is curved to the inside of the vehicle. According to this second conventional example, by adopting the above configuration, the distance between the strut body and the front wheel is expanded,
The kingpin angle and kingpin offset can be reduced at the same time, and the steering force can be significantly reduced.

[0004]

However, in the above-mentioned first conventional example, since the coil spring is arranged on the outer periphery of the strut, if the offset amount of the strut upper attachment point is increased, the strut upper is increased. There is an unsolved problem that the diameter of the spring upper bearing has to be increased in the form of being pushed out to the attachment point, and the outer diameter of the spring also increases, which increases the layout space and the weight.

Further, in the first conventional example, since the inner side of the coil spring and the strut come close to each other, the axial direction of the coil spring is influenced by the axial direction of the strut, and the optimum direction cannot be set. There is also an unsolved problem that bending force works. On the other hand, in the second conventional example, when the axial direction of the strut and the coil spring is offset from the vehicle body mounting bearing, a bending force acts on the bearing portion, and it is necessary to increase the strength of the bearing and the vehicle body side member. When using the anti-vibration rubber for the part, it is necessary to make the anti-vibration rubber hard, and there is an unsolved problem that the anti-vibration function of the rubber deteriorates. Since a large bending force is applied and the inner and outer cylinders of the strut relatively expand and contract while performing circular arc motion, there is an unsolved problem that smooth expansion and contraction is hindered.

Therefore, the present invention has been made by paying attention to the unsolved problem of the above-mentioned conventional example, and prevents the strut from being acted upon by a bending force to prevent the relative movement of the inner and outer cylinders of the strut. An object of the present invention is to provide a strut-type suspension device that can reduce the steering force by reducing the inclination angle of the kingpin shaft while smoothly performing the operation.

[0007]

In order to achieve the above object, the invention according to claim 1 is a strut type suspension device in which a wheel supporting member is supported by a strut, a coil spring, a lower link and a strut. The coil springs are arranged side by side on the strut outside in the vehicle width direction so that the central axes of the springs pass through the connection points of the wheel support member and the lower link, and the bearings for rotating the strut are attached to the upper part of the coil springs. It is characterized by that.

According to the first aspect of the present invention, since the central axis of the coil spring passes through the connecting point between the wheel supporting member and the lower link, this central line serves as the kingpin axis, and the coil spring is located outside the strut in the vehicle width direction. Since they are installed side by side, it is possible to set the tilt angle of the kingpin axis to a small value, and when a vibration input is transmitted from the wheel support member to the strut, a large bending force does not act on the strut, and the strut's The relative movement of the inner cylinder and the outer cylinder can be smoothly performed.

According to a second aspect of the present invention, in the first aspect of the invention, a guide mechanism is provided which allows relative movement in the axial direction between the inner and outer cylinders of the strut and which is relatively non-rotatably connected. It is characterized by having done. According to the second aspect of the present invention, the guide mechanism can reliably prevent the relative rotation of the inner cylinder and the outer cylinder of the strut, and the central axis of the coil spring can be reliably acted as the kingpin axis.

Further, the invention according to claim 3 is based on claim 2
In the invention described above, the guide mechanism includes a guide bar that is integrally provided in parallel with one of the inner and outer cylinders of the strut and a guide that inserts and guides the guide bar that is formed on the other of the inner and outer cylinders of the strut. It is characterized in that it is configured with a member. According to the third aspect of the present invention, the guide bar is inserted into and guided by the guide member, so that the axial relative movement of the inner cylinder and the outer cylinder of the strut is permitted, but the relative rotation of the inner cylinder and the outer cylinder is prevented. As a result, the strut can be reliably rotated about the central axis of the coil spring.

Further, the invention according to claim 4 is the invention according to claim 1, wherein the strut has a plurality of shock absorbers, and the inner cylinders of the shock absorbers are integrally connected. Is characterized by. In the invention of claim 4, since the inner cylinders of the plurality of shock absorbers are integrally connected, the axial movement between the inner cylinder and the outer cylinder of each shock absorber is allowed, but the inner cylinder and the outer cylinder are not permitted. The relative rotation between the cylinders is prevented, and the strut can be reliably rotated about the axis of the coil spring.

Still further, according to the invention of claim 5, in a strut type suspension device in which a wheel supporting member is supported by a strut, a coil spring, and a lower link and a strut, the coil spring is arranged in a vehicle width direction with respect to the strut. It is characterized in that the central axes of the springs are arranged side by side so as to pass through the connection points of the wheel support member and the lower link, and the upper portions of the struts and the coil springs are attached to the vehicle body side member.

According to the fifth aspect of the present invention, since the central axis of the coil spring passes through the connecting point between the wheel support member and the lower link, this central line serves as the kingpin axis, and the coil spring is located outside the strut in the vehicle width direction. Since they are arranged side by side, it is possible to set the tilt angle of the kingpin axis to a small value, and the upper parts of the struts and coil springs are attached to the body side member, so that the vibration input was transmitted from the wheel support member to the struts. At this time, it is possible to reliably prevent a large bending force from being applied to the strut, and it is possible to smoothly perform the relative movement of the inner cylinder and the outer cylinder of the strut.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration showing a first embodiment when the present invention is applied to a front suspension device. In the figure, reference numeral 1 is a knuckle as a wheel supporting member for rotatably supporting a front wheel 2, and an axle 1a for mounting the front wheel 2 is formed in a central portion thereof, and a lower end portion 1b via a ball joint 3 A lower link 4 that allows movement in the vertical direction but restricts movement in the front-back direction is connected, a strut 5 is connected to the upper end portion 1c, and a support portion (not shown) that extends to the rear side of the central portion in the vertical direction is extended. A tie rod connected to the steering device is connected.

The lower link 4 is arranged so as to extend in the vehicle width direction, the outer end of which is attached to the lower end 1b of the knuckle 1 via the ball joint 3 and the inner end of which is suspended via an elastic bush 6. It is linked to member 7. The strut 5 is composed of a shock absorber having a cylinder tube 5a as an outer cylinder and a piston rod 5b as an inner cylinder connected to a piston (not shown) mounted therein and extending outside the cylinder tube 5a. The lower end of the cylinder tube 5a is connected to the upper portion 1c of the knuckle 1 by a mounting bracket 5c.

A spring upper plate 10 extending outward in the vehicle width direction is integrally attached to the upper end of the piston rod 5b, and a spring lower plate extending similarly outward in the vehicle width direction is provided at the center of the cylinder tube 5a in the axial direction. 11 are integrally mounted, and a spiral coil spring 12 is interposed between the spring upper plate 10 and the spring lower plate 11. The central axis of the coil spring 12 is the strut 5.
It is arranged so as to form a kingpin axis L _K which is parallel to the axis line L _{S of the above} and passes through the center of the ball joint 3 connecting the knuckle 1 and the lower link 4 and further through the ground contact center of the front wheel 2.

An opening 10a is formed at a position intersecting with the central axis of the coil spring 12 of the spring upper plate 10, that is, the kingpin axis L _K, and the opening 10a is formed.
A bumper rubber 10b is fixed inside, and an inner ring of a strut-rotating bearing 13 is externally fitted to a projecting portion of the bumper rubber 10b projecting upward from an opening 10a. The outer ring of the bearing 13 is attached to a vehicle body-side member 14. It is internally fitted to the mounted insulator 15. Therefore, the knuckle 1, the strut 5, the spring upper plate 10, the spring lower plate 11 and the coil spring 12 are rotatably supported with respect to the vehicle body side member 14 about the central axis of the bearing 13, that is, the kingpin axis L _K. .

Further, the spring upper plate 10
A guide mechanism 17 is provided between the cylinder tube 5a of the strut 5 and the cylinder tube 5a. As shown in FIG. 2, the guide mechanism 17 includes a pair of guide bars 1 attached to the spring upper plate 10 so as to extend in parallel with the piston rod 5b at symmetrical positions sandwiching the attachment position of the piston rod 5b.
8a, 18b and a guide member 19 attached to the cylinder tube 5a having guide holes 19a, 19b for inserting and guiding the lower ends of the guide bars 18a, 18b, and the cylinder tube 5a and the piston rod 5b.
Is relatively movable in the axial direction and is relatively non-rotatable in the rotation direction.

Next, the operation of the first embodiment will be described. Now, when vertical vibration is input to the front wheels 2 from the road surface, the knuckle 1 moves up and down in response to this, but the lower link 4 allows the lower knuckle 4 to rotate, and the upper end thereof struts. 5 and the coil spring 12 are connected to the vehicle-body-side member 14, the vibration damping characteristic according to the damping force generated by the strut 5 and the spring constant of the coil spring 12 is exerted, and the vibration from the road surface is exerted. It is possible to suppress the transmission of the input to the vehicle body side and obtain a good riding comfort.

When a front-rear direction force is input to the front wheels 2 when passing through unevenness on the road surface, the front-rear direction force causes the knuckle 1 to move in the front-rear direction. In contrast, the lower link 4 causes the knuckle 1 to move. By restricting the movement of the lower end in the front-rear direction, the strut 5, the bearing 13 between the spring upper plate 10 and the vehicle body side member 14, and the mount insulator 15 restrict the movement of the upper end of the knuckle 1 in the front-rear direction. It is possible to regulate the movement in the front-back direction.

Further, when the turning force is transmitted to the knuckle 1 by a steering mechanism (not shown) when the vehicle shifts to a turning state, the knuckle 1 is centered on the central axis of the coil spring 12, that is, the kingpin axis L _K. By rotating the strut 5, the front wheels 2 can be easily steered. At this time, since the guide bar 18 provided on the spring upper plate 10 is inserted and guided in the guide hole 19a of the guide member 19 attached to the cylinder tube 5a of the strut 5, the cylinder tube 5a of the strut and the piston rod 5b. It is possible to compensate for the smooth turning of the front wheels 2 around the kingpin axis L _K without causing relative rotation between them.

In this turning state of the vehicle, a lateral force acts on the front wheels 2, but in this case as well, the lower link 4 restricts the movement of the lower end of the knuckle 1 in the vehicle width direction, and the strut 5, the spring upper plate 10, and the vehicle body. The movement of the knuckle 1 in the vehicle width direction can be regulated by regulating the movement of the upper end of the knuckle 1 in the vehicle width direction with the bearing 13 and the mount insulator 15 between the side member 14.

By the way, in the suspension having the above-described structure, the coil springs 12 for supporting the weight of the vehicle body with respect to the struts 5 are arranged in parallel outside in the vehicle width direction,
Since the upper end of the coil spring 12 is supported by the vehicle body side member 14 via the bearing 13, the coil spring 12 is separated from the strut 5 and the front wheel 2 by a distance D.
Can be placed without being affected by
The inclination angle θ _K of the kingpin axis L _K that connects the center of the coil spring 12 and the bearing 13 to the connection point of the knuckle 1 and the lower link 4 can be reduced, and when the front wheel 2 is steered by the steering mechanism during turning. The steering force can be reduced.

The bearing 13 for rotating the strut is also used.
Is not affected by the position of the strut 5, and the central axis of the coil spring 12, that is, the kingpin axis L.
_Since it is located on _K , the bending force hardly acts and the bearing diameter can be reduced. Further, since the coil spring 12 can be arranged without being affected by the arrangement position of the strut 5, the coil spring 1
The central axis of 2 can be made to coincide with the kingpin axis L _K , and the strut 5 is arranged in parallel with the coil spring 12, so that the spring force of the coil spring 12 acts in parallel with the strut 5. It is possible to reliably prevent the spring force from acting on the strut 5 as a bending force.

On the other hand, since the installation position of the strut 5 can be set without being affected by the position of the kingpin axis L _K , the distance D between the strut 5 and the front wheel 2 can be made sufficiently wide, and at the same time, the strut 5 can be set. The central axis of the strut 5 can be set parallel to the kingpin axis, and smooth movement can be ensured when the strut 5 expands and contracts. Further, since the coil spring 12 is arranged on the outer side in the vehicle width direction with respect to the strut 5, the space for the coil spring is not required on the inner side in the vehicle width direction of the strut 5 as in the conventional example, and the space for the engine room is secured. can do.

In the first embodiment described above, the guide mechanism 17 is provided to restrict the relative rotation of the cylinder tube 5a and the piston rod 5b corresponding to the outer cylinder and the inner cylinder of the strut 5. However, the present invention is not limited to this, and as shown in FIG. 3, a plurality of struts 5 themselves, for example, two sets of struts 5A, 5B.
And the cylinder tube 5a of both struts 5A and 5B is integrated with the bracket 20 and the piston rod 5b is integrated with the spring upper plate 10. The rotation may be restricted.

Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the present invention is applied to a rear suspension device, and the spring upper plate 10, the bumper rubber 10b, the bearing 13, and the mount insulator 15 in the above-described first embodiment are omitted. , The upper end of the piston rod 5b of the strut 5 is attached to the body-side member 21 by the rubber cushion 2
2, the upper end of the coil spring 12 is directly attached to the vehicle body side member 21 via the spring vibration-proof rubber 23, and the rear wheel 24 is rotatably supported by the knuckle 1, and the lower wheel is also attached. 1 has the same configuration as that of FIG. 1 except that the inner end of the link 4 in the vehicle width direction is attached to a bracket 25 formed on the vehicle body side member 21 instead of the suspension member 7.
Corresponding parts are designated by the same reference numerals, and detailed description thereof will be omitted.

Also in the second embodiment, the central axis of the coil spring 12 is the kingpin shaft having a small inclination angle θ _K , as in the first embodiment except that the wheels cannot be steered. L _K can be made to coincide with each other, and the bending force acting on the strut 5 when a vertical vibration input is transmitted to the strut 5 can be significantly reduced, and further smooth when the strut 5 expands and contracts. Such movements can be compensated for, and the space inside the strut 5 in the vehicle width direction can be further reduced to secure a large space in the luggage compartment.

In the first and second embodiments described above, the case where the axis of the strut 5 and the central axis of the coil spring 12 are arranged parallel to each other has been described, but the present invention is not limited to this and both of them are arranged. It is not necessary to arrange them in strict parallel, and they may be arranged in parallel at an angle within a range in which the action of the spring force does not affect the expansion and contraction of the struts.

Further, in the first and second embodiments, the case where the coil spring 12 formed in a spiral shape is applied has been described, but the present invention is not limited to this, and a conical coil spring or other shapes. You may make it apply the coil spring of.

[0031]

As described above, according to the first aspect of the invention, since the central axis of the coil spring passes through the connecting point between the wheel support member and the lower link, this central line serves as the kingpin axis, and this coil Since the springs are juxtaposed outside the struts in the vehicle width direction, it is possible to set the tilt angle of the kingpin axis to a small value, and when the vibration input is transmitted from the wheel support member to the struts, a large bending force is applied to the struts. The effect that the relative movement of the inner cylinder and the outer cylinder of the strut can be smoothly performed without the action of.

Further, according to the invention of claim 2, in the invention of claim 1, relative rotation of the inner cylinder and the outer cylinder of the strut can be reliably prevented by the guide mechanism, and the central axis of the coil spring can be prevented. It is possible to obtain the effect that the kingpin shaft can be reliably operated. further,
According to the invention of claim 3, in the invention of claim 2, the guide bar, in which the guide mechanism is fixed to one of the inner and outer cylinders of the strut, is inserted and guided in the guide member fixed to the other, The inner cylinder and the outer cylinder of the strut are allowed to move relative to each other in the axial direction, but the relative rotation of the inner cylinder and the outer cylinder is prevented, and the strut can be reliably rotated about the central axis of the coil spring. The effect is obtained.

Further, according to the invention of claim 4, in the invention of claim 1, since the inner cylinders of the plurality of shock absorbers are integrally connected, the inner cylinder and the outer cylinder of each shock absorber are connected. Although the movement in the axial direction is allowed, the relative rotation between the inner cylinder and the outer cylinder is blocked, and the effect that the strut can be reliably rotated about the axis of the coil spring is obtained.

Still further, according to the invention of claim 5, since the central axis of the coil spring passes through the connecting point of the wheel support member and the lower link, this central line serves as a kingpin axis, and this coil spring serves as a vehicle from the strut. Since they are arranged side by side on the outside in the width direction, it is possible to set the tilt angle of the kingpin axis to a small value, and the upper parts of the struts and coil springs are attached to the body side member, so vibration input from the wheel support member to the struts. Is transmitted, it is possible to reliably prevent a large bending force from being applied to the strut, and it is possible to smoothly perform relative movement between the inner cylinder and the outer cylinder of the strut.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment when the present invention is applied to a front suspension device.

FIG. 2 is a side view showing the guide mechanism of FIG.

FIG. 3 is a side view showing another example of the strut.

FIG. 4 is a schematic configuration diagram showing an embodiment when the present invention is applied to a rear suspension device.

[Explanation of Codes] 1 Knuckle 2 Front Wheel 3 Ball Joint 4 Lower Link 5 Strut 5a Cylinder Tube 5b Piston Rod 10 Spring Upper Plate 11 Spring Lower Plate 12 Coil Spring 13 Bearing 14 Vehicle Body Side Member 15 Mount Insulator 17 Guide Mechanism 18 Guide Bar 19 Guide member L _K Kingpin shaft 21 Body side member 22 Anti-vibration rubber 23 Spring anti-vibration rubber 24 Rear wheel

Claims (5)

[Claims] 1. A strut-type suspension device in which a wheel support member is supported by struts, coil springs, and lower links, wherein the coil spring is outside the vehicle width direction with respect to the struts and the center axis of the spring is a wheel support member. And a lower link, which are arranged in parallel so as to pass through a connecting point, and the bearing for rotating the strut is attached to an upper portion of the coil spring. 2. A strut-type suspension device according to claim 1, further comprising a guide mechanism for permitting relative movement in the axial direction between the inner cylinder and the outer cylinder of the strut and for connecting the strut so as not to rotate relative to each other. . 3. The guide mechanism inserts and guides a guide bar integrally provided in one of the inner and outer cylinders of the strut and the guide bar formed in the other of the inner and outer cylinders of the strut. The strut-type suspension device according to claim 2, wherein the strut-type suspension device comprises a guide member. 4. The strut-type suspension device according to claim 1, wherein the strut has a plurality of shock absorbers, and the inner cylinders of the shock absorbers are integrally connected to each other. 5. A strut-type suspension device in which a wheel support member is supported by struts, coil springs, and lower links, wherein the coil spring is outside the vehicle width direction with respect to the struts and the spring center axis is a wheel support member. And a lower link, which are arranged side by side so as to pass through the connecting point, and the upper parts of the struts and the coil springs are attached to a member on the vehicle body side.