JP7239306B2 - Strut type suspension device - Google Patents

Description

The present invention relates to a strut-type suspension system.

Conventionally, a shock absorber and a strut mount are provided, and the central axis of the shock absorber and the kingpin axis when viewed from the front-rear direction of the vehicle gradually extend outward in the left-right direction of the vehicle from the top toward the bottom. Strut-type suspension devices are known in which the inclination angle of the shaft with respect to the vertical direction is greater than the inclination angle of the central axis with respect to the vertical direction.
As a strut-type suspension device of this type, for example, as disclosed in Patent Document 1 below, when a tire and a cylinder rotate integrally around a kingpin axis in accordance with steering, the inner peripheral surface of the cylinder is displaced from the left and right sides of the vehicle. A configuration is known in which a belt-shaped high friction coefficient region extending in the central axis direction and having a higher friction coefficient than other portions is formed in a portion positioned at the end of the direction. In this configuration, when the steering wheel is turned, the piston of the shock absorber is pressed against the high friction coefficient region located at the end in the left-right direction of the vehicle on the inner peripheral surface of the cylinder due to the centrifugal force generated in the vehicle body. The sliding resistance of the rod with respect to the cylinder in the direction of the central axis is increased, and the damping force exerted by the shock absorber is increased. As a result, it is possible to suppress the roll at the time of steering.

JP 2014-46861 A

However, in the conventional strut-type suspension device, when the vehicle turns at a low speed, the pressing force of the piston against the high friction coefficient region is small, and there is a problem that it is difficult to suppress the roll.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a strut-type suspension device capable of suppressing a roll even when the vehicle is turning at a low speed.

In order to solve the above problems, the present invention proposes the following means.
A strut-type suspension device according to the present invention includes a shock absorber and a strut mount, and when viewed in the vehicle front-rear direction, the central axis of the shock absorber and the kingpin axis gradually extend in the vehicle left-right direction from above to below. an inner member extending outward and having a kingpin axis with a greater inclination angle with respect to the vertical direction than the central axis with respect to the vertical direction, wherein the strut mount includes an inner member to which the upper end of the rod of the shock absorber is fixed; The inner member is disposed between an outer member that surrounds the inner member in a circumferential direction along the center axis and is attached to the vehicle body, and the inner member and the outer member are arranged relative to each other. and a main body rubber that supports elastically displaceable, and the shock absorber is arranged between the inner member and the outer member, along with the steering, around the connecting portion between the rod and the inner member, and the outer member. An assist rubber is provided that is compressed and deformed by coming into contact with the inner member or the outer member when rotated in the front-rear direction with respect to the member, and causes the rod to generate a reaction force around the connecting portion.

In the present invention, when viewed from the vehicle front-rear direction, the central axis of the shock absorber and the kingpin axis gradually extend outward in the vehicle left-right direction from the top toward the bottom, and the angle of inclination of the kingpin axis with respect to the vertical direction increases. , is larger than the inclination angle of the central axis with respect to the vertical direction, the shock absorber rotates in the vehicle longitudinal direction with respect to the outer member around the connecting portion between the rod and the inner member when the steering is steered.
An assist rubber is disposed between the inner member and the outer member, and when the shock absorber rotates in the longitudinal direction of the vehicle with respect to the outer member around the connecting portion as the steering is turned, the assist rubber is provided. The rubber contacts the inner member or the outer member and compressively deforms, causing the rod to generate a reaction force around the connecting portion. Therefore, when the steering is turned, the reaction force applied from the assist rubber to the rod via the inner member makes it possible for the shock absorber to strongly press the piston against the end of the inner peripheral surface of the cylinder in the longitudinal direction of the vehicle. It is possible to increase the sliding resistance of the rod with respect to the cylinder in the direction of the central axis. That is, when the steering wheel is turned, the piston can be strongly pressed against the end of the inner peripheral surface of the cylinder in the longitudinal direction of the vehicle, regardless of the centrifugal force generated during turning. Roll can be suppressed.

Here, the outer member includes a pair of support portions that cover the main body rubber from both sides in the vertical direction, and the assist rubbers are arranged on both sides sandwiching the rod in the vehicle front-rear direction as viewed in the vehicle left-right direction. In addition, it may protrude from the main body rubber on both sides in the vertical direction and face the pair of support portions in the vertical direction.

In this case, the assist rubbers are arranged on both sides sandwiching the rod in the longitudinal direction of the vehicle when viewed in the lateral direction of the vehicle, protrude from the main rubber on both sides in the vertical direction, and face the pair of support portions in the vertical direction. Therefore, it is possible to reliably suppress the rolling even when the vehicle is turning at a low speed regardless of the direction of steering.

Further, when the shock absorber rotates about the connecting portion in the vehicle front-rear direction with respect to the outer member, the reaction force received by the rod is such that the shock absorber rotates about the connecting portion around the outer member. It may be larger than the reaction force that the rod receives when it rotates in the vehicle left-right direction with respect to.

In this case, when the shock absorber rotates about the connecting portion in the lateral direction of the vehicle with respect to the outer member during straight running, it is possible to suppress the reaction force received by the rod, which deteriorates the ride comfort. can be suppressed.
It should be noted that the angle at which the shock absorber rotates in the longitudinal direction of the vehicle with respect to the outer member around the connecting portion during straight running is generally smaller than during steering and vertical stroke. Therefore, even if the shock absorber rotates around the connecting portion in the longitudinal direction of the vehicle with respect to the outer member when the shock absorber is traveling straight ahead, the reaction force that the rod receives from the assist rubber is small. Deterioration of comfort is unlikely to occur.

According to the present invention, it is possible to suppress the roll even during turning at low speed.

1 is a cross-sectional view along the vehicle left-right direction of a main part of a strut-type suspension device according to an embodiment of the present invention; FIG. 2 is a partially enlarged view of the strut-type suspension device shown in FIG. 1; FIG. 3 is a cross-sectional view along the vehicle front-rear direction of the strut-type suspension device shown in FIG. 2 ; FIG. 4 is a diagram showing a state in which the shock absorber rotates in the vehicle front-rear direction with respect to the outer member around the connecting portion between the rod and the inner member as the strut-type suspension device shown in FIG. 3 is steered;

An embodiment of a strut-type suspension device according to the present invention will be described below with reference to FIGS. 1 to 4. FIG.

The strut-type suspension device 1 includes a hub 11 that rotatably supports a wheel (front wheel) W, a knuckle 12 that protrudes inward in the left-right direction X of the vehicle from the hub 11, and a knuckle 12 that stands upward. a strut mount 17 to which the upper end of the rod 16 of the shock absorber 13 is attached; and a lower arm positioned below the lower end of the shock absorber 13 and extending inward in the vehicle left-right direction X from the knuckle 12. 14, a ball joint portion 15 that connects the lower arm 14 and the knuckle 12, a spring 18 that integrally supports the rod 16 and the strut mount 17 in an upwardly biased state so that they can move downward, and tie rods and brakes (not shown). apparatus and the like.

The shock absorber 13 gradually extends inward in the vehicle left-right direction X as it goes upward, and includes a rod 16 and a cylinder 19 . Rod 16 and cylinder 19 are arranged coaxially with a common axis. Hereinafter, this common axis will be referred to as the rod axis (central axis) O, and the direction that intersects the rod axis O when viewed from the direction of the rod axis O will be referred to as the radial direction. The direction of rotation is called the circumferential direction.

Rod 16 protrudes upward from cylinder 19 . A male thread is formed at the upper end of the rod 16 . A lower end portion of the cylinder 19 is located inside the ball joint portion 15 in the left-right direction X of the vehicle. A lower end portion of the cylinder 19 is positioned above the ball joint portion 15 . A lower end of the cylinder 19 is fixed to the knuckle 12 . A support plate 29 that supports the lower end of the spring 18 is attached to the outer peripheral surface of the cylinder 19 .

The strut mount 17 includes an inner member 21 to which the upper end of the rod 16 of the shock absorber 13 is fixed, an outer member 22 that surrounds the inner member 21 in the circumferential direction and is attached to the vehicle body B side, the inner member 21 and the outer member 22. and a main body rubber 23 disposed between and supporting the inner member 21 and the outer member 22 so as to be relatively elastically displaceable.

The inner member 21 is formed in an annular shape, and the upper end of the rod 16 is inserted therein. The upper end of the rod 16 is fixed to the inner member 21 by screwing a nut 25 onto a portion of the upper end of the rod 16 that protrudes upward from the inner member 21 . The inner member 21 is arranged coaxially with the rod axis O.
As shown in FIGS. 1 and 2, the outer member 22 includes an inner tubular portion 26 that surrounds the inner member 21 from the outside in the radial direction, and an outer tubular portion 24 in which the inner tubular portion 26 is fitted. Prepare. The inner cylinder portion 26 and the outer cylinder portion 24 are arranged coaxially with the rod axis O. As shown in FIG.

In the inner cylindrical portion 26, the inner and outer diameters of the upper portion 26a are larger than the inner and outer diameters of the lower portion 26b.
The outer cylindrical portion 24 is divided in the vertical direction Y. As shown in FIG. The upper portion 26 a of the inner tubular portion 26 is fitted into the upper portion 24 a of the outer tubular portion 24 , and the lower portion 26 b of the inner tubular portion 26 is fitted into the lower portion 24 b of the outer tubular portion 24 . A flange portion that protrudes radially outward and is arranged on the upper surface of the vehicle body B is formed at the lower end portion of the upper portion 24 a of the outer cylinder portion 24 . An upper end portion of a lower portion 24b of the outer cylinder portion 24 is fitted into a mounting hole formed in the vehicle body B. As shown in FIG.
The main rubber 23 connects the inner peripheral surface of the inner cylindrical portion 26 and the inner member 21 . The body rubber 23 is formed in an annular shape and arranged coaxially with the rod axis O. As shown in FIG. The elastic center of the body rubber 23 is located on the rod axis O. As shown in FIG.

The outer member 22 includes a pair of support portions 22a that cover the main rubber body 23 from both sides in the vertical direction Y. As shown in FIG. In the illustrated example, the support portions 22a are arranged separately at the upper end portion of the upper portion 24a of the outer cylindrical portion 24 and the lower end portion of the lower portion 24b of the outer cylindrical portion 24. As shown in FIG. The pair of support portions 22a covers the outer peripheral edge portion of the inner member 21 from both sides in the vertical direction Y. As shown in FIG. The pair of support portions 22a are formed in an annular shape and arranged coaxially with the rod axis O. As shown in FIG. Of the pair of support portions 22 a , the lower surface of the support portion 22 a positioned below supports the upper end portion of the spring 18 .

Here, a tie rod (not shown) is connected to the end of the knuckle 12 in the vehicle front-rear direction Z. As shown in FIG. The tie rod pushes the end portion of the knuckle 12 in the vehicle front-rear direction Z outward in the vehicle left-right direction X or pulls it inward in the vehicle left-right direction X during steering, thereby integrating the knuckle 12 and the wheel W. , around the kingpin axis K connecting the center of the ball joint portion 15 and the connecting portion P between the rod 16 and the inner member 21 . The connecting portion P serves as the elastic center of the main rubber 23, for example.
The kingpin axis K gradually extends outward in the left-right direction X of the vehicle as it goes downward from above. The angle of inclination of the kingpin axis K with respect to the vertical direction Y is larger than the angle of inclination of the rod axis O with respect to the vertical direction Y when viewed from the vehicle front-rear direction Z.

In the present embodiment, an assist rubber 31 is provided between the inner member 21 and the outer member 22, so that the shock absorber 13 moves as shown in FIGS. 3 and 4 as the steering is turned. When the connecting portion P between the rod 16 and the inner member 21 is rotated in the vehicle longitudinal direction Z with respect to the outer member 22, the assist rubber 31 contacts the inner member 21 or the outer member 22 and is compressed and deformed. A reaction force around the connecting portion P is generated in the rod 16 .

The assist rubber 31 is formed integrally with the main rubber 23 . In addition, the assist rubber 31 may be arranged on the inner member 21 or the outer member 22 apart from the main rubber 23 .
The assist rubbers 31 are arranged on both sides of the rod 16 in the longitudinal direction Z of the vehicle when viewed in the lateral direction X of the vehicle. A plurality of assist rubbers 31 are formed at intervals in the circumferential direction at respective portions of the body rubber 23 located on both sides of the rod 16 in the vehicle front-rear direction Z. As shown in FIG.

The assist rubber 31 protrudes on both sides in the vertical direction Y from the main rubber 23 and faces the pair of support portions 22a in the vertical direction Y. As shown in FIG. The assist rubbers 31 formed on the upper surface and the lower surface of the main rubber body 23 are approximately the same in size, and are substantially symmetrical in shape. The assist rubber 31 is in contact with or close to the support portion 22a in the up-down direction Y. As shown in FIG. The radial positions of the assist rubbers 31 formed on the upper surface and the lower surface of the main rubber body 23 and the outer peripheral edge portion of the inner member 21 are equal to each other.

As shown in FIG. 2 , covering rubbers 32 are provided on respective portions of the outer peripheral edge portion of the inner member 21 that are located on both sides of the rod 16 in the lateral direction X of the vehicle. The covering rubber 32 is arranged on the upper and lower surfaces of the inner member 21 . The covering rubber 32 is formed integrally with the main rubber 23 . A gap is provided in the vertical direction Y between the covering rubber 32 and the support portion 22a. The volume of the covering rubber 32 is smaller than the volume of the assist rubber 31 .
When the shock absorber 13 rotates around the connecting portion P in the vehicle longitudinal direction Z with respect to the outer member 22, the reaction force received by the rod 16 is such that the shock absorber 13 rotates around the connecting portion P, It is larger than the reaction force that the rod 16 receives when it rotates in the vehicle left-right direction X with respect to the outer member 22 .

As the amount of rotational movement of the shock absorber 13 in the vehicle longitudinal direction Z with respect to the outer member 22 around the connecting portion P increases, the reaction force generated in the rod 16 around the connecting portion P and the rod of the rod 16 with respect to the cylinder 19 gradually increase. The sliding resistance in the direction of axis O increases. The relationship between the amount of rotational movement and the sliding resistance can be adjusted by designing the size and material of the assist rubber 31 according to the characteristics of the shock absorber 13 .

As described above, according to the strut-type suspension device 1 according to the present embodiment, the rod axis O and the kingpin axis K gradually move in the vehicle left-right direction X as viewed from the vehicle front-rear direction Z as they go downward. Extending outward, the angle of inclination of the kingpin axis K with respect to the vertical direction Y is greater than the angle of inclination of the rod axis O with respect to the vertical direction Y. It rotates in the vehicle front-rear direction Z with respect to the outer member 22 around the connecting portion P.

Assist rubbers 31 are arranged between the inner member 21 and the outer member 22, and the shock absorber 13 moves around the connection portion P with respect to the outer member 22 in the vehicle longitudinal direction Z as the steering is turned. , the assist rubber 31 abuts against the outer member 22 and is compressed and deformed, causing the rod 16 to generate a reaction force around the connecting portion P. As shown in FIG. Therefore, when the steering is turned, the reaction force applied from the assist rubber 31 to the rod 16 via the inner member 21 strongly presses the piston of the shock absorber 13 against the end of the inner peripheral surface of the cylinder 19 in the vehicle front-rear direction Z. As a result, the sliding resistance of the rod 16 with respect to the cylinder 19 in the direction of the rod axis O can be increased. That is, when the steering wheel is turned, the piston can be strongly pressed against the end of the inner peripheral surface of the cylinder 19 in the longitudinal direction Z of the vehicle, regardless of the centrifugal force generated by the turning. roll can be suppressed.

Assist rubbers 31 are disposed on both sides of the rod 16 in the vehicle front-rear direction Z when viewed in the vehicle left-right direction X, and protrude from the body rubber 23 on both sides in the up-down direction Z to form a pair of support portions 22a. Since they are opposed to each other in the vertical direction Z, it is possible to reliably suppress roll even when turning at low speed regardless of the direction of steering.

Further, when the shock absorber 13 rotates around the connection portion P in the vehicle front-rear direction Z with respect to the outer member 22, the reaction force received by the rod 16 is such that the shock absorber 13 rotates around the connection portion P, It is larger than the reaction force that the rod 16 receives when it rotates in the vehicle left-right direction X with respect to the outer member 22 .
Therefore, when the shock absorber 13 rotates in the vehicle left-right direction X with respect to the outer member 22 around the connection portion P during straight running, it is possible to suppress the reaction force received by the rod 16 to be small. It is possible to prevent the deterioration of comfort.

It should be noted that the angle at which the shock absorber 13 rotates in the vehicle longitudinal direction X with respect to the outer member 22 around the connecting portion P during straight running is generally smaller than during steering and vertical stroke. Therefore, even if the shock absorber 13 rotates in the vehicle front-rear direction X with respect to the outer member 22 around the connection portion P during straight running, the reaction force that the rod 16 receives from the assist rubber 31 is small. Deterioration of ride comfort due to the provision of is unlikely to occur.

The technical scope of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention.

In the above-described embodiment, the sizes of the assist rubbers 31 formed on the upper and lower surfaces of the main rubber body 23 are substantially the same, and the shapes thereof are substantially symmetrical. They may be different from each other.
Also, the assist rubber 31 may be formed in an annular shape extending continuously over the entire circumference.
In addition, although the covering rubbers 32 are provided on the respective portions located on both sides of the rod 16 in the lateral direction X of the vehicle, the covering rubbers 32 do not have to be provided.

In addition, it is possible to appropriately replace the constituent elements in the above-described embodiment with well-known constituent elements without departing from the spirit of the present invention, and the above-described modified examples may be combined as appropriate.

Reference Signs List 1 strut-type suspension device 13 shock absorber 16 rod 17 strut mount 21 inner member 22 outer member 22a support portion 23 main rubber 31 assist rubber B vehicle body K kingpin axis O rod axis (central axis)
P connecting portion X vehicle left-right direction Y vertical direction Z vehicle front-back direction

Claims (2)

Equipped with shock absorbers and strut mounts,
When viewed from the front-rear direction of the vehicle, the center axis of the shock absorber and the kingpin axis gradually extend outward in the vehicle left-right direction from top to bottom, and the angle of inclination of the kingpin axis with respect to the up-down direction is equal to the center. larger than the tilt angle with respect to the vertical direction of the axis,
The strut mount is
an inner member to which the upper end of the rod of the shock absorber is fixed;
an outer member that surrounds the inner member in a circumferential direction along the central axis and is attached to the vehicle body;
a main rubber disposed between the inner member and the outer member and supporting the inner member and the outer member so as to be relatively elastically displaceable;
When the shock absorber rotates between the inner member and the outer member in the vehicle front-rear direction with respect to the outer member around the connecting portion between the rod and the inner member due to steering, an assist rubber that is compressed and deformed in contact with the inner member or the outer member and causes the rod to generate a reaction force around the connecting portion ;
a central axis of the shock absorber is a common axis of a cylinder provided in the shock absorber and the rod projecting upward from the cylinder;
The kingpin axis is an axis that connects the center of the ball joint that connects the lower arm of the vehicle and the knuckle to which the wheel is attached, and the connecting portion,
When the shock absorber is rotated in the longitudinal direction of the vehicle about the connecting portion with respect to the outer member, the reaction force received by the rod rotates the shock absorber about the connecting portion with respect to the outer member. larger than the reaction force received by the rod when it rotates in the vehicle left-right direction,
Strut type suspension device. The outer member includes a pair of support portions that cover the main rubber from both sides in the vertical direction,
The assist rubbers are disposed on both sides sandwiching the rod in the longitudinal direction of the vehicle when viewed in the left-right direction of the vehicle, protrude from the main rubber on both sides in the vertical direction, and face the pair of support portions in the vertical direction. 2. The strut-type suspension system according to claim 1, wherein

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