JP3602307B2 - Trailing arm suspension - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a trailing arm suspension for a motor vehicle.
[0002]
[Prior art]
Conventionally, as a rear suspension of an automobile, for example, a trailing arm type as shown in FIGS. 3 and 4 has been known (May 10, 1994, Toyota RAV4L New Model Vehicle Description, Service by Toyota Motor Corporation) (See pages 2-49 to 2-52, edited by the Ministry of Internal Affairs, and Toyota RAV4 L, Toyota RAV4J repair book on May 10, 1994, edited by Toyota Motor Corporation Service Division, pages 6-49, 6-54.) That is, this suspension is connected to the trailing arm 2 having one end 2a fixed to the vehicle body via the arm bush 1 and the other end 2b supporting the wheel H, and the other end of the trailing arm 2. A pair of upper arm 3 and lower arm 4 for receiving a load mainly in the lateral direction (vehicle width direction) of the vehicle body, a spring 5 for receiving a load mainly in the vertical direction of the trailing arm 2 on the front side F of the vehicle body with respect to the wheel center O, It is provided on the vehicle body side coaxially with the spring 5 and contacts the trailing arm 2 to prevent the suspension from directly hitting the vehicle body (preventing interference) when the spring 5 is fully contracted at full bound. The bumper bar 6, which determines the upper limit of the movement, and the front end between the other end of the trailing arm 2 and the vehicle body side. And a thick absorber 7 for attenuating the vertical vibration with generated shock absorption by the spring 5.
[0003]
In such a suspension, by setting the spring constant of the arm bush 1 provided at the one end 2a of the trailing arm 2 to be low, it is possible to suppress vibration and vibration noise and secure a good ride comfort. Even if the spring constant is set low, there is an advantage that there is no deviation in wheel alignment at the time of shock absorption, and it is widely used mainly as a rear suspension for front-wheel drive vehicles and four-wheel drive vehicles.
[0004]
[Problems to be solved by the invention]
However, in the suspension described above, both the spring 5 and the bump rubber 6 are arranged closer to the arm bush 1 than the wheel center O. For this reason, at the time of the full bound, the trailing arm 2 acts as a lever at the contact position A with the bump rubber 6, that is, the load transmission position at which the input load is transmitted to the bump rubber 6, while the trailing arm 2 Is subjected to a downward load by the spring 5, a large downward load is applied to the one end 2a of the trailing arm 2, and the arm bush 1 is greatly deformed (bent). For this reason, if the spring constant of the arm bush 1 is set too low, an overstroke phenomenon occurs in which the wheel center O becomes higher than the set position at full bound. Therefore, it is necessary to increase the vertical spring constant of the arm bush 1, and there is a limit in adjusting the spring constant to improve the riding comfort.
[0005]
On the other hand, in the above-described suspension, since the spring 5 and the bump rubber 6 are coaxially arranged, the input load at the time of full bound is concentrated on the trailing arm 2 and one point on the vehicle body side. For this reason, the strength required for the trailing arm 2 and the vehicle body is high, which has been a factor that hinders the weight reduction and cost reduction of the vehicle body and the trailing arm 2.
[0006]
The present invention has been made in view of such circumstances, and can prevent the overstroke phenomenon at the wheel center during full bound, can set the spring constant of the arm bush lower than before, and can reduce the weight and weight. It is an object of the present invention to provide a trailing arm type suspension capable of reducing costs.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, according to the present invention, one end 2a is fixed to a vehicle body via an arm bush 1 while the other end is supported by a trailing arm 2 supporting a wheel H. A pair of upper arm 3 and lower arm 4 that are connected and mainly receive a load in the vehicle width direction, a spring 5 that receives a mainly upward load input to the trailing arm 2, and mainly prevent interference between the suspension and the vehicle body. To prevent the trailing arm 2 from moving upward at the other end of the trailing arm 2, the bumper bar 6 determining the upward movement limit. A first load transmitting position A is set, and the spring 5 is provided between the first load transmitting position A and the vehicle body. A second load transmitting position B is set on the trailing arm 2 on the rear side of the vehicle body with respect to the center O of the wheel H, and a shock absorber 7 is provided between the second load transmitting position B and the vehicle body; the provided the Banparaba 6 on the vehicle body side attachment points of the shock absorbers 7, the upward movement direction side that put the other end of the trailing arm 2 via the shock absorber 7 is restricted by the Banparaba 6, When the other end of the trailing arm 2 reaches the upward movement limit, a part of the load applied to the other end of the trailing arm 2 by the bump rubber 6 is moved to the lower end of the shock absorber 7. 2 is attached to the second load transmission position B so as to be applied as an upward load to one end 2a of the second end 2a.
In this configuration, when the other end side of the front Symbol trailing arm 2 reaches the movement limit of the upward direction, the one end of the trailing arm, spring applied from the center of the wheel to the first load transmission position of the front side of the vehicle body , And a part of the load by the bumper bar 6 applied to the second load transmission position on the rear side of the vehicle body from the center of the wheel , both of which are opposite to each other (the former is downward). On the other hand, the latter is upward), so that the downward load applied to one end of the trailing arm is smaller than before. In addition, since the spring and the bumper bar are installed at different locations, the input load during full bound does not concentrate on one point, and the strength required for the vehicle body and the trailing arm is reduced.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings. Figures 1 and 2 are views illustrating a suspension according to the present invention. As can be seen, the suspension of the present embodiment, that have the same basic configuration as that already theory with FIGS.
[0010]
That is, in the suspension, the one end 2a is fixed to the vehicle body side via the arm bush 1 and a trailing arm 2 wheel H is supported on the other end 2b, the other end of the trailing arm 2 A pair of upper arms 3 and a lower arm 4 that are connected and mainly receive a load in the lateral direction of the vehicle (vehicle width direction) are provided. The trailing arm 2 is provided with a connecting protrusion 2b at the other end located on the rear side of the vehicle body from the center O of the wheel H, and a shock absorber 7 is provided between the connecting protrusion 2b and the vehicle body. I have. The shock absorber 7 has an outer cylinder part 7a connected to the trailing arm 2 and a piston rod 7b connected to the vehicle body. A bumper bar 6 is fixedly provided at the upper end side of the piston rod 7b of the shock absorber 7 at a position away from the outer cylinder portion 7a, and a lower end portion of the bumper bar 6 slides on the upper end side of the outer cylinder portion 7a. A guide stopper 13 on a cylinder that is movably fitted to the outside is fixed. The bump rubber 6 is located on the rear side of the vehicle body with respect to the center O of the wheel H of the side member 11 provided on the vehicle body, and thereby determines the upward movement limit of the trailing arm 2 at full bound. . That is, at the time of the full bound, the upper end of the outer cylinder portion 7a of the shock absorber 7 abuts on the bump rubber 6 via the guide stopper 13, so that the upward movement of the trailing arm 2 exceeding the set amount is restricted. At the same time, when the vehicle moves upward beyond the set amount, the load applied to the other end of the trailing arm 2 by the bump rubber 6 is applied to the one end 2a of the trailing arm 2 as an upward load. . Further, the trailing arm 2 is provided with a circular support projection 2c located forward of the vehicle body with respect to the center O of the wheel H. The spring 5 is compressed between the support projection 2c and the vehicle body. Is established. That is, in the present embodiment, the support protrusion 2c of the trailing arm 2 is in the first load transmitting position A in the present invention, and the connecting protrusion 2b of the trailing arm 2 is in the second load transmitting position in the present invention. B.
[0011]
In the embodiment having the above configuration, while the end of the trailing arm 2 is attached downward load of the spring 5 at all times, at the time of full bound, partially trailing load entered into the trailing arm 2 An upward load is applied to one end 2 a of the arm 2. Therefore, the vertical load applied to the one end 2a of the trailing arm 2 at the time of full bound becomes a difference between the two opposite loads described above, and is smaller than the conventional one. Therefore, even when the spring constant of the arm bush 1 at the one end 2a of the trailing arm 2 is set lower than before, the amount of deformation of the arm bush 1 at full bound can be suppressed. For this reason, even if the spring constant of the arm bush 1 is set low, it is possible to prevent the overstroke phenomenon at the center of the wheel H at full bound, and it is possible to set the spring constant of the arm bush 1 lower. As a result, the riding comfort can be further improved.
[0012]
Further , since the spring 5 and the bump rubber 6 are provided at different positions from each other, the input load at the time of full bound does not concentrate on the trailing arm 2 or one point on the vehicle body side. Therefore, since the strength required for the vehicle body and the trailing arm is lower than before, the weight and cost of the vehicle body and the trailing arm can be reduced. Further, the strength between the trailing arm 2 and the vehicle body can be easily secured, and the degree of freedom in design can be increased.
[0013]
【The invention's effect】
As described above, in the suspension of the present invention, when the other end of the trailing arm reaches the upper limit, the load applied to one end of the trailing arm by the spring and the load input to the trailing arm are reduced. The directions of the loads on both the part and the part are opposite to each other, so that the downward load applied to one end of the trailing arm is reduced as compared with the conventional case.
[0014]
Therefore, even when the spring constant of the arm bush at one end of the trailing arm is set lower than before, the amount of deformation of the arm bush at full bound can be suppressed, and the spring constant of the arm bush is set lower. However, it is possible to prevent the overstroke phenomenon at the wheel center at the time of full bound. Further, it is possible to further improve the riding comfort.
[0015]
In addition, by setting the first load transmission position to the front of the vehicle body and the second load transmission position to the rear of the vehicle body with the center of the wheel therebetween, the installation locations of the spring and the bump rubber are different from each other, Since the input load does not concentrate on one point, the strength required for the vehicle body and the trailing arm decreases. Therefore, the weight and cost of the vehicle body and the trailing arm can be reduced. Further, the strength between the trailing arm and the vehicle body can be easily secured, and the degree of freedom in design can be increased.
[Brief description of the drawings]
FIG. 1 is a plan view showing an embodiment of the present invention.
FIG. 2 is a front view of FIG.
FIG. 3 is a plan view showing a conventional technique.
FIG. 4 is a front view of FIG . 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Arm bush 2 Trailing arm 3 Upper arm 4 Lower arm 5 Spring 6 Bump rubber 7 Shock absorber A First load transmitting position B Second load transmitting position H Wheel O Wheel center

Claims (1)

One end 2a is fixed to the vehicle body via an arm bush 1, the other end supports a wheel H, and a pair of upper arms connected to the trailing arm 2 to mainly receive a load in a vehicle width direction. 3 and a lower arm 4, a spring 5 for receiving a load mainly applied to the trailing arm 2 in an upward direction, and mainly preventing interference between a suspension and a vehicle body, and an upper portion on the other end side of the trailing arm 2. In the trailing arm type suspension equipped with the bumper bar 6 that determines the movement limit to
A first load transmitting position A is set on the trailing arm 2 at a position forward of the vehicle body from a center O of the wheel H, and the spring 5 is provided between the first load transmitting position A and the vehicle body. A second load transmission position B is set on the trailing arm 2 on the rear side of the vehicle body from the center O of the wheel H, and a shock absorber 7 is provided between the second load transmission position B and the vehicle body. the Banparaba 6 provided on the vehicle body side mounting portion of the absorber 7, the upward movement direction side that put the other end of the trailing arm 2 via the shock absorber 7 is restricted by the Banparaba 6, wherein the shock the lower end of the absorber 7, the other end of the trailing arm 2 when it reaches the movement limit of the upward and entered to the other end of the trailing arm 2 As part of the load by the serial Banparaba 6 it is applied as upward load to one end 2a of the trailing arm 2, trailing arm, characterized in that attached to the second load transmission position B.

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