JPH05104922A - Trailing arm fitting structure - Google Patents

Abstract

PURPOSE:To reduce the longitudinal oscillation of a wheel center at the bumping-rebounding time. CONSTITUTION:An approximately cylindrical fitting hole 3a is formed at the front end part of a trailing arm 3, and a rotary shaft 4 fixed to the body side is disposed in this fitting hole 3a. The upper and lower parts of the rotary shaft 4 are provided with an upper stopper 5 and a lower stopper 6 of plate shape extended upward or downward longitudinally in the thickness direction. A bush 7 is divided longitudinally with the upper and lower stoppers 5, 6 held in between, and a rear bush 7a is removably opposed to the rear faces of both stoppers 5, 6 and set to be higher in rigidity than a front bush 7b. The front bush 7b is provided with a cavity 7c so as to be easily deformed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-body-side mounting structure for a trailing arm used in a suspension for connecting a vehicle body and an axle, and more particularly to a trailing arm mounting characterized by a bush used in the mounting structure. Regarding the structure.

[0002]

2. Description of the Related Art A conventional trailing arm has its rear end connected to an axle supporting a wheel with its shaft facing forward and backward, and its front end connected to a vehicle body side member so as to be vertically rotatable. The structure of the mounting portion on the vehicle body side is such that a substantially cylindrical mounting hole having a shaft oriented in the vehicle width direction is formed at a front end portion of the arm, and a rotary shaft fixed to a vehicle body side member is bushed in the mounting hole. When the wheel bumps and rebounds, the trailing arm rotates up and down about the vehicle body side mounting shaft as a fulcrum.

The elastic force of the bush is uniform.

[0004]

However, in the above-mentioned conventional trailing arm, when the wheel bumps or rebounds, the vehicle body side mounting portion that is the front end of the arm is used as the center of rotation, and the trailing arm is located behind the center of rotation. Since a certain wheel center rotates up and down, the wheel center moves back and forth in an arc in accordance with the bump and rebound,
There is a problem that the torsion bar or the like is twisted according to the displacement, and roll steer occurs in the wheel.

The present invention has been made in view of the above problems, and an object thereof is to reduce the rocking of the wheel center in the front-rear direction during bumping and rebounding.

[0006]

In order to achieve the above object, the trailing arm mounting structure of the present invention is fixed to the vehicle body side in a substantially cylindrical mounting hole formed at one end. In a trailing arm in which a rotating shaft is inserted through a bush and rotatably supported by a vehicle body in the vertical direction, a plate-shaped upper stopper that is integrated with the rotating shaft and extends upward and downward from the rotating shaft, respectively. And a lower stopper is provided, and among the bushes, the rear bush located on the wheel side of both stoppers has higher rigidity, and the rear bush is opposed to both stoppers so that they can come into contact with and separate from each other. There is.

Further, as described in claim 2,
In a trailing arm in which a rotary shaft fixed to the vehicle body is inserted through a bush into a substantially cylindrical mounting hole formed at one end to be rotatably supported by the vehicle body, the mounting hole is Separately from the mounting hole, a second mounting hole is formed in the trailing arm at a predetermined axial distance from the mounting hole, and a second mounting hole is inserted into the mounting hole via a bush and is fixed to the vehicle body. The bushes, each having two rotating shafts, are respectively disposed on the two mounting portions, and one end portion is fixed to the rotating shaft to extend obliquely upward on the wheel side, and the other end portion is fixed to the inner peripheral surface of each mounting hole. Mounting a trailing arm, comprising a first bush and a second bush projecting upward from a lower side of the inner peripheral surface of the mounting hole and having an upper end surface facing the rotating shaft so as to be capable of contacting and separating from the rotating shaft. It may be elephants.

[0008]

In the trailing arm mounting structure according to the first aspect of the present invention, when the wheel bumps, the wheel center tries to rotate upward about the rotation shaft fixed to the vehicle body side member, but when the wheel rotates by a predetermined amount. The upper stopper provided on the rotating shaft contacts the wheel-side bush. Then, since the bush engaged with the upper stopper has high rigidity, the rotation center moves from the center of the rotation shaft to the engagement point between the upper stopper and the bush, that is, moves upward due to the resistance of the bush. The forward displacement of the wheel center connected to the rear end of the trailing arm is reduced, and the roll steer is accordingly reduced. Further, since the bush in the front of the vehicle body is less rigid than the bush in the rear of the vehicle body with the stopper interposed therebetween, the bush on the front side of the vehicle body is bent and the rotating shaft is displaced forward in the vehicle body in the mounting hole, so that the tray is relatively moved. As the ring arm moves to the rear of the vehicle body, the forward displacement of the wheel center becomes smaller and the roll steering becomes smaller.

When the wheel rebounds, it tries to rotate downward about the center of the rotary shaft as described above, but when the wheel rotates a predetermined amount, the lower stopper provided on the rotary shaft causes the bush on the wheel side to rotate. Contact with. Then, since the bush engaged with the lower stopper has high rigidity, the rotation center moves from the center of the rotating shaft to the engaging portion between the lower stopper and the bush, that is, moves downward due to the resistance of the bush. Therefore, the amount of forward displacement of the wheel center to which the rear end of the arm is connected is small, and the roll steer is accordingly small. further,
Since the bush in front of the vehicle body is less rigid than the bushes in the rear of the vehicle body with both stoppers sandwiched between them, the bush in front of the vehicle body is bent and the rotating shaft is displaced forward in the vehicle body in the mounting hole, and the trailing arm is relatively moved. Moves rearward to further reduce the forward displacement of the wheel center and further reduce the roll steer.

In the trailing arm mounting structure according to the second aspect, the center of rotation is located between the two mounting portions formed on the trailing arm in the initial state. When the wheel bumps, the wheel center first rotates upward with the position as the center of rotation, but when the wheel rotates a predetermined amount, the rotation shaft of the mounting portion near the wheel engages with the lower second bush, The spring constant of the second bush increases and becomes rigid, and the rotation center moves to the engaging portion. Then, in the other mounting portion, the rotary shaft separates from the second bush and the first bush is compressed between the rotary shaft and the mounting hole, and the trailing arm is compressed by the compression of the first bush in the compression direction of the first bush. That is, the amount of forward displacement of the wheel center, which is pushed rearward and is connected to the rear end of the arm, is reduced, and the roll steer is accordingly reduced.

When the wheel rebounds, the wheel center first rotates downward about the aforementioned position as the center of rotation, but when it rotates a predetermined amount, the rotation shaft of the front mounting portion engages with the lower second bush. Similarly to the above, the rotation center moves to the engaging portion. Then, in the other mounting portion, the rotary shaft separates from the second bush, the first bush is compressed, and the trailing arm is pushed backward by the compression of the first bush, and the rear end portion of the arm is connected. The amount of forward displacement of the existing wheel center becomes smaller, and the roll steering becomes smaller accordingly.

[0012]

Embodiments of the present invention will be described with reference to the drawings.
This embodiment is an example applied to a trailing arm of a torsion beam axle type suspension. First, the structure of the suspension will be described. As shown in FIG. 2, the left and right knuckle spindles 1 that rotatably support left and right wheels (not shown) are rigidly connected to the ends of the torsion beam 2 that is laid horizontally in the vehicle width direction. Are connected. Trailing arms 3 on the left and right knuckle spindles 1, respectively
The rear end portion is connected, and the trailing arm 3 is connected at its front end portion to a body-side member (not shown) rotatably via a bush.

In FIG. 2, 30 is a coil spring, 31 is a shock absorber, 32 is a pan plover, and 33 is a Panhard rod. The structure of the mounting portion of the trailing arm 3 on the vehicle body side is as follows.
As shown in FIG. 1, a substantially cylindrical mounting hole 3a having a shaft in the vehicle width direction is formed at the front end of the trailing arm 1,
A rotary shaft 4 fixed to the vehicle body side is disposed in the mounting hole 3a coaxially with the mounting hole 3a.

A plate-like upper stopper 5 and a lower stopper 6 extending upward or downward respectively above and below the rotary shaft 4 are provided.
Are provided with the thickness direction in the front-back direction. A bush 7 is filled between the rotary shaft 4 and the mounting hole 3a. The bush 7 is divided into front and back with the upper and lower stoppers 5 and 6 interposed therebetween, and the rear bush 7a faces the rear surfaces of the both stoppers 5 and 6 in a contactable and separable manner and has a rigidity higher than that of the front bush 7b. It's getting higher. Further, the front bush 7b has a void 7c, which facilitates deformation.

In the trailing arm mounting structure having the above construction, when the wheels bump, the trailing arm 3
Moves upward centering on the vehicle body side attachment portion connected to the vehicle body side, drawing a locus of an arc in which the rear end portion side is convex toward the rear of the vehicle body. At this time, at the vehicle body side mounting portion of the trailing arm 3, as shown in FIG. 3, the upper stopper 5 integrated with the rotating shaft 4 engages with the front bush 7a, but the front bush 7a is rigid. Therefore, the rotation center moves to the engaging portion A between the upper stopper 5 and the front bush 7a due to the resistance of the front bush 7a. As a result, the center of rotation moves upward with the upward movement of the wheel center, and the forward displacement of the wheel center is reduced. Further, the front bush 7b is more than the rear bush 7a.
Has a lower rigidity, the front bush 7b bends, and the position of the rotating shaft 4 in the mounting hole 3a moves toward the front side of the vehicle body with the engaging portion as the center, so that the trailing arm 3 is relatively moved. By moving to the rear of the vehicle body, the forward displacement of the wheel center is further reduced.

When the wheel rebounds, the wheel center rotates downward about the vehicle body side mounting portion of the trailing arm 3. At this time, at the vehicle body side mounting portion of the trailing arm 3, as shown in FIG.
The lower stopper 6 integrated with the rotating shaft 4 engages with the front bush 7a to press the front bush 7a, but the front bush 7a resists the pressing, so that the rotation center of the trailing arm 3 rotates. Lower stopper 6 from shaft 4
To the engaging portion B between the rear bush 7a and the rear bush 7a. Further, since the rear bush 7a has higher rigidity than the front bush 7b, the front bush 7b bends and the rotary shaft 4 moves inside the mounting hole 3a. The trailing arm 3 itself is displaced to the front, and the trailing arm 3 itself moves to the rear of the vehicle body, so that the displacement of the wheel center to the front is reduced in the same manner as described above.

As can be seen from the above operation, when the wheel bumps and rebounds, the center of rotation P moves upward and downward in accordance with the vertical movement of the wheel side, and as shown in FIG. The displacement S becomes smaller than that of the conventional one, and the trailing arm 3 itself is displaced rearward, so that the displacement S in the front is further reduced, and the trajectory H of the wheel center is linearized in the vertical direction. In addition, in FIG. 5, the curve shown by the dotted line is the trajectory of the conventional wheel center.

As a result, the roll steer generated by the wheel center being displaced forward and backward and the torsion bar 2 being twisted is reduced as shown in FIG. 6, and the running performance is stabilized. In FIG. 6, the dotted line indicates the conventional roll steer, and the solid line indicates the roll steer according to the present invention. Next, a second embodiment will be described.

Trailing arm 3 in the second embodiment
As shown in FIG. 7, the vehicle-body-side mounting structure is configured to include two mounting portions provided at the front end of the trailing arm 3 with a predetermined gap in the axial direction.
The two mounting portions are respectively provided with rotating shafts 4 and 9 fixed to a vehicle body side member (not shown) at the centers of substantially cylindrical mounting holes 3a and 3b formed in the trailing arm 3. The rotating shafts 4, 9 and the mounting holes 3a, 3
It is connected to b through the first bushes 8a and 10a. The first bushes 8a, 10a have one end fixed to the rotary shafts 4, 9 and extend obliquely upward to the rear of the vehicle from the rotary shafts 4, 9 and the other end fixed to the mounting holes 3a, 3b side. Are provided.

Below the rotary shafts 4 and 9, second bushes 8b and 10b, whose lower ends are fixed to the lower sides of the mounting holes 3a and 3b, extend upward and upper end parts are attached to the rotary shafts 4 and 9. It is detachably faced. The bushes 11 and 12 in the drawing face the front and rear of the rotating shafts 4 and 9, respectively, and can be engaged when the trailing arm 3 swings in the front-rear direction.

In the mounting structure of the trailing arm 3 having the above structure, when the wheel bumps and rebounds, the trailing arm 3 rotates about the central position X between the two mounting portions as the center of rotation. However, when the wheel rotates by a predetermined amount, one of the rotating shafts 4 and 9 is moved to the second bush 8
It engages with b and 10b, and the rotation center shifts to the engaging portion.
For example, at the time of bumping, as shown in FIG. 8, the rotary shaft 9 on the rear side of the vehicle body engages with the second bush 10b and the second bush 1b
The rigidity of 0b increases, and the center of rotation moves to the engaging portion X1. At this time, on the mounting portion side in the front of the vehicle body, the rotary shaft 4 and the second bush 8b are separated from each other with the engaging portion X as the center, and the first bush 8a is compressed, whereby the trailing arm 3 causes the rotary shaft 4 to move. Is pushed in the compression direction, that is, toward the rear of the vehicle body, and the trailing arm 3 itself is displaced toward the rear of the vehicle body to reduce the displacement of the wheel center drawn by the trailing end of the trailing 3 toward the front of the vehicle body.

Further, at the time of rebound, as shown in FIG. 9, the rotating shaft 4 on the mounting portion side in front of the vehicle body collides with the second bush 8b, and the rotation center moves to the engaging portion X2. Accordingly, in the mounting portion on the rear side of the vehicle body, the rotating shaft 9 moves in a direction away from the second bush 10b, and
The first bush 10a is compressed, and the trailing arm 3 is pushed rearward from the rotary shaft 9 by the compression, whereby the trailing arm 3 itself is displaced rearward, and the wheel center drawn by the rear end of the trailing arm 3 is drawn. The displacement of the front of the vehicle is reduced.

As described above, as in the first embodiment, the trailing arm moves backward in accordance with the vertical movement of the wheel during bumping and rebounding of the wheel, whereby the forward displacement S of the wheel center is reduced. The trailing arm 3 itself becomes smaller than the conventional one, and the trailing arm 3 itself is displaced rearward, so that the displacement S in the front direction is further reduced, and the trajectory H of the wheel center is linearized vertically. As a result, the wheel center is displaced back and forth and the torsion bar 2
The roll steer generated by twisting is reduced, and the running performance is stabilized.

Further, in the second embodiment, since the elastic force of the bush can be selected, it is possible to select the elastic force according to the force input in the front-rear direction.

[0025]

As described above, in the trailing arm mounting structure of the present invention, the forward displacement of the wheel center at the time of bumping and rebounding becomes small, and therefore the torsion bar is twisted due to the displacement. Roll roll steering can be reduced, and stability of the vehicle body during rolling is improved.

[0026]

FIG. 1 is a side view showing a mounting structure of a trailing arm according to a first embodiment of the present invention.

[0027]

FIG. 2 is a perspective view showing a torsion beam axle type suspension to which the present invention is applied.

[0028]

FIG. 3 is a side view showing a state at the time of bumping in the first embodiment.

[0029]

FIG. 4 is a side view showing a state at the time of rebound in the first embodiment.

[0030]

FIG. 5 is a diagram showing a trajectory of a wheel center in the first embodiment.

[0031]

FIG. 6 is a diagram showing a relationship between a wheel bump, rebound, and roll steer.

[0032]

FIG. 7 is a side view showing a mounting structure of a trailing arm according to a second embodiment of the present invention.

[0033]

FIG. 8 is a side view showing a state during bumping in the second embodiment.

[0034]

FIG. 9 is a side view showing a state during rebound in the second embodiment.

[0035]

[Explanation of symbols]

 3 Trailing arms 3a, 3b Mounting holes 4, 9 Rotating shaft 5 Upper stopper 6 Lower stopper 7 Bushings 8a, 10a 1st bush 8b, 10b 2nd bush

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[Procedure amendment]

[Submission date] October 15, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-body-side mounting structure for a trailing arm used in a suspension for connecting a vehicle body and an axle, and more particularly to a trailing arm mounting characterized by a bush used in the mounting structure. Regarding the structure.

[0002]

2. Description of the Related Art A conventional trailing arm has its rear end connected to an axle supporting a wheel with its shaft facing forward and backward, and its front end connected to a vehicle body side member so as to be vertically rotatable. The structure of the mounting portion on the vehicle body side is such that a substantially cylindrical mounting hole having a shaft oriented in the vehicle width direction is formed at a front end portion of the arm, and a rotary shaft fixed to a vehicle body side member is bushed in the mounting hole. When the wheel bumps and rebounds, the trailing arm rotates up and down about the vehicle body side mounting shaft as a fulcrum.

The elastic force of the bush is uniform.

[0004]

However, in the above-mentioned conventional trailing arm, when the wheel bumps or rebounds, the vehicle body side mounting portion that is the front end of the arm is used as the center of rotation, and the trailing arm is located behind the center of rotation. Since a certain wheel center rotates up and down, the wheel center moves back and forth in an arc in accordance with the bump and rebound,
There is a problem that the torsion bar or the like is twisted according to the displacement, and roll steer occurs in the wheel.

The present invention has been made in view of the above problems, and an object thereof is to reduce the rocking of the wheel center in the front-rear direction during bumping and rebounding.

[0006]

In order to achieve the above object, the trailing arm mounting structure of the present invention is fixed to the vehicle body side in a substantially cylindrical mounting hole formed at one end. In a trailing arm in which a rotating shaft is inserted through a bush and rotatably supported by a vehicle body in the vertical direction, a plate-shaped upper stopper that is integrated with the rotating shaft and extends upward and downward from the rotating shaft, respectively. And a lower stopper is provided, and among the bushes, the rear bush located on the wheel side of both stoppers has higher rigidity, and the rear bush is opposed to both stoppers so that they can come into contact with and separate from each other. There is.

Further, as described in claim 2,
In a trailing arm in which a rotary shaft fixed to the vehicle body is inserted through a bush into a substantially cylindrical mounting hole formed at one end to be rotatably supported by the vehicle body, the mounting hole is Separately from the mounting hole, a second mounting hole is formed in the trailing arm at a predetermined axial distance from the mounting hole, and a second mounting hole is inserted into the mounting hole via a bush and is fixed to the vehicle body. The bushes, each having two rotating shafts, are respectively disposed on the two mounting portions, and one end portion is fixed to the rotating shaft to extend obliquely upward on the wheel side, and the other end portion is fixed to the inner peripheral surface of each mounting hole. Mounting a trailing arm, comprising a first bush and a second bush projecting upward from a lower side of the inner peripheral surface of the mounting hole and having an upper end surface facing the rotating shaft so as to be capable of contacting and separating from the rotating shaft. It may be elephants.

[0008]

In the trailing arm mounting structure according to the first aspect of the present invention, when the wheel bumps, the wheel center tries to rotate upward about the rotation shaft fixed to the vehicle body side member, but when the wheel rotates by a predetermined amount. The upper stopper provided on the rotating shaft contacts the wheel-side bush. Then, since the bush engaged with the upper stopper has high rigidity, the rotation center moves from the center of the rotation shaft to the engagement point between the upper stopper and the bush, that is, moves upward due to the resistance of the bush. The forward displacement of the wheel center connected to the rear end of the trailing arm is reduced, and the roll steer is accordingly reduced. Further, since the bush in the front of the vehicle body is less rigid than the bush in the rear of the vehicle body with the stopper interposed therebetween, the bush on the front side of the vehicle body is bent and the rotating shaft is displaced forward in the vehicle body in the mounting hole, so that the tray is relatively moved. As the ring arm moves to the rear of the vehicle body, the forward displacement of the wheel center becomes smaller and the roll steering becomes smaller.

When the wheel rebounds, it tries to rotate downward about the center of the rotary shaft as described above, but when the wheel rotates a predetermined amount, the lower stopper provided on the rotary shaft causes the bush on the wheel side to rotate. Contact with. Then, since the bush engaged with the lower stopper has high rigidity, the rotation center moves from the center of the rotating shaft to the engaging portion between the lower stopper and the bush, that is, moves downward due to the resistance of the bush. Therefore, the amount of forward displacement of the wheel center to which the rear end of the arm is connected is small, and the roll steer is accordingly small. further,
Since the bush in front of the vehicle body is less rigid than the bushes in the rear of the vehicle body with both stoppers sandwiched between them, the bush in front of the vehicle body is bent and the rotating shaft is displaced forward in the vehicle body in the mounting hole, and the trailing arm is relatively moved. Moves rearward to further reduce the forward displacement of the wheel center and further reduce the roll steer.

In the trailing arm mounting structure according to the second aspect, the center of rotation is located between the two mounting portions formed on the trailing arm in the initial state. When the wheel bumps, the wheel center first rotates upward with the position as the center of rotation, but when the wheel rotates a predetermined amount, the rotation shaft of the mounting portion near the wheel engages with the lower second bush, The spring constant of the second bush increases and becomes rigid, and the rotation center moves to the engaging portion. Then, in the other mounting portion, the rotary shaft separates from the second bush and the first bush is compressed between the rotary shaft and the mounting hole, and the trailing arm is compressed by the compression of the first bush in the compression direction of the first bush. That is, the amount of forward displacement of the wheel center, which is pushed rearward and is connected to the rear end of the arm, is reduced, and the roll steer is accordingly reduced.

When the wheel rebounds, the wheel center first rotates downward about the aforementioned position as the center of rotation, but when it rotates a predetermined amount, the rotation shaft of the front mounting portion engages with the lower second bush. Similarly to the above, the rotation center moves to the engaging portion. Then, in the other mounting portion, the rotary shaft separates from the second bush, the first bush is compressed, and the trailing arm is pushed backward by the compression of the first bush, and the rear end portion of the arm is connected. The amount of forward displacement of the existing wheel center becomes smaller, and the roll steering becomes smaller accordingly.

[0012]

Embodiments of the present invention will be described with reference to the drawings.
This embodiment is an example applied to a trailing arm of a torsion beam axle type suspension. First, the structure of the suspension will be described. As shown in FIG. 2, the left and right knuckle spindles 1 that rotatably support left and right wheels (not shown) are rigidly connected to the ends of the torsion beam 2 that is laid horizontally in the vehicle width direction. Are connected. Trailing arms 3 on the left and right knuckle spindles 1, respectively
The rear end portion is connected, and the trailing arm 3 is connected at its front end portion to a body-side member (not shown) rotatably via a bush.

In FIG. 2, 30 is a coil spring, 31 is a shock absorber, 32 is a pan plover, and 33 is a Panhard rod. The structure of the mounting portion of the trailing arm 3 on the vehicle body side is as follows.
As shown in FIG. 1, a substantially cylindrical mounting hole 3a having a shaft in the vehicle width direction is formed at the front end of the trailing arm 1,
A rotary shaft 4 fixed to the vehicle body side is disposed in the mounting hole 3a coaxially with the mounting hole 3a.

A plate-like upper stopper 5 and a lower stopper 6 extending upward or downward respectively above and below the rotary shaft 4 are provided.
Are provided with the thickness direction in the front-back direction. A bush 7 is filled between the rotary shaft 4 and the mounting hole 3a. The bush 7 is divided into front and back with the upper and lower stoppers 5 and 6 interposed therebetween, and the rear bush 7a faces the rear surfaces of the both stoppers 5 and 6 in a contactable and separable manner and has a rigidity higher than that of the front bush 7b. It's getting higher. Further, the front bush 7b has a void 7c, which facilitates deformation.

In the trailing arm mounting structure having the above construction, when the wheels bump, the trailing arm 3
Moves upward centering on the vehicle body side attachment portion connected to the vehicle body side, drawing a locus of an arc in which the rear end portion side is convex toward the rear of the vehicle body. At this time, at the vehicle body side mounting portion of the trailing arm 3, as shown in FIG. 3, the upper stopper 5 integrated with the rotating shaft 4 engages with the front bush 7a, but the front bush 7a is rigid. Therefore, the rotation center moves to the engaging portion A between the upper stopper 5 and the front bush 7a due to the resistance of the front bush 7a. As a result, the center of rotation moves upward with the upward movement of the wheel center, and the forward displacement of the wheel center is reduced. Further, the front bush 7b is more than the rear bush 7a.
Has a lower rigidity, the front bush 7b bends, and the position of the rotating shaft 4 in the mounting hole 3a moves toward the front side of the vehicle body with the engaging portion as the center, so that the trailing arm 3 is relatively moved. By moving to the rear of the vehicle body, the forward displacement of the wheel center is further reduced.

When the wheel rebounds, the wheel center rotates downward about the vehicle body side mounting portion of the trailing arm 3. At this time, at the vehicle body side mounting portion of the trailing arm 3, as shown in FIG.
The lower stopper 6 integrated with the rotating shaft 4 engages with the front bush 7a to press the front bush 7a, but the front bush 7a resists the pressing, so that the rotation center of the trailing arm 3 rotates. Lower stopper 6 from shaft 4
To the engaging portion B between the rear bush 7a and the rear bush 7a. Further, since the rear bush 7a has higher rigidity than the front bush 7b, the front bush 7b bends and the rotary shaft 4 moves inside the mounting hole 3a. The trailing arm 3 itself is displaced to the front, and the trailing arm 3 itself moves to the rear of the vehicle body, so that the displacement of the wheel center to the front is reduced in the same manner as described above.

As can be seen from the above operation, when the wheel bumps and rebounds, the center of rotation P moves upward and downward in accordance with the vertical movement of the wheel side, and as shown in FIG. The displacement S becomes smaller than that of the conventional one, and the trailing arm 3 itself is displaced rearward, so that the displacement S in the front is further reduced, and the trajectory H of the wheel center is linearized in the vertical direction. In addition, in FIG. 5, the curve shown by the dotted line is the trajectory of the conventional wheel center.

As a result, the roll steer generated by the wheel center being displaced forward and backward and the torsion bar 2 being twisted is reduced as shown in FIG. 6, and the running performance is stabilized. In FIG. 6, the dotted line indicates the conventional roll steer, and the solid line indicates the roll steer according to the present invention. Next, a second embodiment will be described.

Trailing arm 3 in the second embodiment
As shown in FIG. 7, the vehicle-body-side mounting structure is configured to include two mounting portions provided at the front end of the trailing arm 3 with a predetermined gap in the axial direction.
The two mounting portions are respectively provided with rotating shafts 4 and 9 fixed to a vehicle body side member (not shown) at the centers of substantially cylindrical mounting holes 3a and 3b formed in the trailing arm 3. The rotating shafts 4, 9 and the mounting holes 3a, 3
It is connected to b through the first bushes 8a and 10a. The first bushes 8a, 10a have one end fixed to the rotary shafts 4, 9 and extend obliquely upward to the rear of the vehicle from the rotary shafts 4, 9 and the other end fixed to the mounting holes 3a, 3b side. Are provided.

Below the rotary shafts 4 and 9, second bushes 8b and 10b, whose lower ends are fixed to the lower sides of the mounting holes 3a and 3b, extend upward and upper end parts are attached to the rotary shafts 4 and 9. It is detachably faced. The bushes 11 and 12 in the drawing face the front and rear of the rotating shafts 4 and 9, respectively, and can be engaged when the trailing arm 3 swings in the front-rear direction.

In the mounting structure of the trailing arm 3 having the above structure, when the wheel bumps and rebounds, the trailing arm 3 rotates about the central position X between the two mounting portions as the center of rotation. However, when the wheel rotates by a predetermined amount, one of the rotating shafts 4 and 9 is moved to the second bush 8
It engages with b and 10b, and the rotation center shifts to the engaging portion.
For example, at the time of bumping, as shown in FIG. 8, the rotary shaft 9 on the rear side of the vehicle body engages with the second bush 10b and the second bush 1b
The rigidity of 0b increases, and the center of rotation moves to the engaging portion X1. At this time, on the mounting portion side in the front of the vehicle body, the rotary shaft 4 and the second bush 8b are separated from each other with the engaging portion X as the center, and the first bush 8a is compressed, whereby the trailing arm 3 causes the rotary shaft 4 to move. Is pushed in the compression direction, that is, toward the rear of the vehicle body, and the trailing arm 3 itself is displaced toward the rear of the vehicle body to reduce the displacement of the wheel center drawn by the trailing end of the trailing 3 toward the front of the vehicle body.

Further, at the time of rebound, as shown in FIG. 9, the rotating shaft 4 on the mounting portion side in front of the vehicle body collides with the second bush 8b, and the rotation center moves to the engaging portion X2. Accordingly, in the mounting portion on the rear side of the vehicle body, the rotating shaft 9 moves in a direction away from the second bush 10b, and
The first bush 10a is compressed, and the trailing arm 3 is pushed rearward from the rotary shaft 9 by the compression, whereby the trailing arm 3 itself is displaced rearward, and the wheel center drawn by the rear end of the trailing arm 3 is drawn. The displacement of the front of the vehicle is reduced.

As described above, as in the first embodiment, the trailing arm moves backward in accordance with the vertical movement of the wheel during bumping and rebounding of the wheel, whereby the forward displacement S of the wheel center is reduced. The trailing arm 3 itself becomes smaller than the conventional one, and the trailing arm 3 itself is displaced rearward, so that the displacement S in the front direction is further reduced, and the trajectory H of the wheel center is linearized vertically. As a result, the wheel center is displaced back and forth and the torsion bar 2
The roll steer generated by twisting is reduced, and the running performance is stabilized.

Further, in the second embodiment, since the elastic force of the bush can be selected, it is possible to select the elastic force according to the force input in the front-rear direction.

[0025]

As described above, in the trailing arm mounting structure of the present invention, the forward displacement of the wheel center at the time of bumping and rebounding becomes small, and therefore the torsion bar is twisted due to the displacement. Roll roll steering can be reduced, and stability of the vehicle body during rolling is improved.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Added

[Correction content]

[Brief description of drawings]

FIG. 1 is a side view showing a mounting structure of a trailing arm according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a torsion beam axle type suspension to which the present invention is applied.

FIG. 3 is a side view showing a state at the time of bumping in the first embodiment.

FIG. 4 is a side view showing a state at the time of rebound in the first embodiment.

FIG. 5 is a diagram showing a trajectory of a wheel center in the first embodiment.

FIG. 6 is a diagram showing a relationship between a wheel bump, rebound, and roll steer.

FIG. 7 is a side view showing a mounting structure of a trailing arm according to a second embodiment of the present invention.

FIG. 8 is a side view showing a state during bumping in the second embodiment.

FIG. 9 is a side view showing a state during rebound in the second embodiment.

[Explanation of symbols] 3 Trailing arms 3a, 3b Mounting holes 4, 9 Rotating shaft 5 Upper stopper 6 Lower stopper 7 Bushings 8a, 10a First bushes 8b, 10b Second bushes

Claims (2)

[Claims] 1. A tray in which a rotary shaft fixed to the vehicle body is inserted through a bush into a substantially cylindrical mounting hole formed at one end thereof and is supported by the vehicle body so as to be vertically rotatable. In the ring arm, a plate-shaped upper stopper and a lower stopper which are integrated with the rotary shaft and extend upward and downward from the rotary shaft are provided, and a rear bush of the bush located on the wheel side of both stoppers. The trailing arm mounting structure is characterized in that the rigidity is increased and the rear side bush is opposed to both stoppers so as to be able to contact and separate from each other. 2. A trailing arm rotatably supported on a vehicle body by inserting a rotary shaft fixed to the vehicle body through a bush into a substantially cylindrical mounting hole formed at one end. In addition to the mounting hole, a second mounting hole is formed on the trailing arm at a predetermined distance from the mounting hole in the axial direction, and a second mounting hole is inserted into the mounting hole via a bush and is attached to the vehicle body side. A bush having a second rotating shaft that is fixed, and the bushes that are respectively disposed in the two mounting portions have one end fixed to the rotating shaft and extend diagonally upward on the wheel side, and the other end is attached to each of them. A tray comprising a first bush fixed to the inner peripheral surface of the hole and a second bush projecting upward from a lower side of the inner peripheral surface of the mounting hole and having an upper end surface facing the rotating shaft so as to come into contact with and separate from the rotary shaft. Lingua Attachment structure