JPS5940910A - Car suspension device - Google Patents

Abstract

PURPOSE:To apply the self-steering function to two rear shafts by constituting the rear shaft fitting side of a torque rod lower than the trunnion shaft fitting side in a two-rear shaft trunnion-type suspension device with a lower torque rod. CONSTITUTION:When a car is turned to the left, for example, it is tilted to the right side of the proceeding direction. Thereby, a large downward force FD is applied to the right side trunnion shaft 3, it pushes down the fitting joint 2a section of the right side lower torque rod 2, swings the torque rod 2 by an angle DELTAalpha, then increases the distance CR between the fitting joints 2b of the first and second shafts 4, 5. On the other hand, a push-up force is applied to the left side, thus decreasing the distance between fitting joints 2b, 2d. Thereby, the self- steering function is generated in two rear shafts 4, 5. At this time, the displacement of two rear shafts 4, 5 is absorbed by the rubber R and smooth self-steering can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle suspension system, and in particular, provides a large inclination angle to the lower torque rond of a rear two-axle trunnion type suspension system, thereby making it possible for the rear two axles to move smoothly when the vehicle turns. This invention relates to a suspension system for a self-steering vehicle.

In the conventional two-axle trunnion type suspension system, the rear two axles do not have a steering function, so the turning radius of the vehicle tends to be large, and side force is generated when the vehicle turns, which increases tire wear. Another drawback is that excessive internal stress is generated in each part of the suspension system. There has also been a proposal (Special Publication No. 5O-25691) in which the rear two axles are linked to the steering operation of the front axle, but this would result in an increase in weight as the rock structure would become a double track.
The problem was that the cost was high.

The present invention has been made in order to eliminate the drawbacks of the prior art described above, and its purpose is to provide a trunnion type suspension for supporting two rear axles of a vehicle with a pair of lower torque rods on each side. In the device, a large inclination angle is given to the lower torque rod, and a rubber member is interposed between the rear two-wheel axle housing and the leaf spring. The second method is to use the difference in the swing angle of the lower torque rod on the left and right sides of the vehicle to force the rear two axles to perform a self-steering function with an extremely simple force configuration. The objective is to improve vehicle maneuverability by reducing the dynamic turning radius of the vehicle, reduce tire wear by reducing side force, and improve durability by reducing internal stress in the suspension system. . Another objective is to enable a lighter design of the suspension system by reducing internal stresses.

In short, the present invention provides a trunnion-type suspension system that includes a pair of lower torque rods on the left and right sides and supports two rear axles of a vehicle, in which at least the pair of lower torque rods are positioned at respective mounting joints to the trunnion shaft. , the mounting joints for the first rear shaft and the second rear shaft are mounted at lower positions, and the axle housing of the first moving shaft and one end of the leaf spring are fixed via a rubber member, The axle housing of the rear second shaft and the other end of the leaf spring are fixed via a rubber member, so that when the vehicle tilts from side to side due to turning, the swing angle of the lower torque rod changes. Taking advantage of the fact that the left and right sides of the vehicle are 1, the first rear axle and the second rear axle are moved closer to each other on one side of the vehicle and separated from each other on the other side to perform self-steering. It is characterized in that the rubber member is configured to absorb the displacement of the rear two axes that occurs.

The present invention will be explained below based on embodiments shown in the drawings. A vehicle suspension system 1 according to the present invention includes a trunnion type suspension system T.
The lower torque rod 2 is provided with a pair of T-portion I torque rods 2 on each side in the direction of travel of the vehicle, and the lower torque rod 2 has a mounting joint 2a to the trunnion shaft 3 mounted at a high position. The attachment joint portions 2b to the first apprentice shaft 4 and the second rear shaft 5 are each mounted at a lower position. This also applies to the pair of upper torque rods 6 attached to the center of the vehicle. That is, the lower torque rod 2 has a steep slope in the front and rear direction from the attachment joint 2a for the trunnion shaft 3 toward the attachment joint 2a for the rear first shaft 4 and the rear second shaft 5. , the angle α of each lower torque rod 2 is set to α<1800. The trunnion shaft 3 is fixed to the chassis frame 8 via a trunnion bracket 7, and a leaf spring 9 is fixed to the trunnion shaft 3 by a U bolt 10.
The axle housing 11 of the rear first shaft 4 and one end 9a of the leaf spring 9 are fixed via a rubber member R.
axle nozzle 12 and the other end 9a of the leaf spring 9
is fixed via a rubber member R. Rear 1st axis 4
And the second moving shaft 5 has wheels 13 and 14, respectively! It is attached.

5- Then, when the vehicle tilts to the left or right due to turning, the swing angle of the lower torque rod 2 is different on the left and right sides of the vehicle. The structure is such that self-steering is performed by bringing them close to each other on one side and separating them from each other on the opposite side, and the displacement of the rear two shafts 4 and 5 caused by the self-steering is absorbed by the rubber member R.

Note that rubber bushings (not shown) are attached to the mounting joints 2a and 2b of the torque rod 2.

The present invention is constructed as described above, and its operation will be explained below. As shown in FIG. 4, for example, when a vehicle attempts to turn to the left as indicated by arrow A, the centrifugal force acts in the right direction in the direction of travel, so that the vehicle tilts to the right due to the resultant force of the vehicle's own weight. Then, as shown in FIG. 2, a large downward force FD acts on the right side chassis frame 8 of the trunnion type suspension T and the right side of the trunnion shaft 3, so that the lower torque rod 2 on the right side is attached to the trunnion shaft 3. The joint part 2a moves downward by a large distance, and the lower torque rod 2 swings by an angle Δα from the solid line state to the virtual line state, and the angle α is large.As a result, the mounting joint part 2b moves forward. As shown in FIG. 4, the first rear shaft 4 is pushed forward and the second rear shaft 5 is pushed backward, and they are separated from each other.

On the other hand, on the left side of the vehicle, the trunnion shaft 3 is lifted upward by the upward force FU, so the third
As shown in the figure, as the angle α of the lower torque rod 2 becomes smaller, the lower torque rod swings by Δα from the solid line state to the virtual line state. As a result, the joint part 2b moves by a distance t in the front and rear directions, and the distance CL is not short, and as shown in FIG. 4, the rear first shaft 4 moves rearward,
The rear second shafts 5 are each drawn forward and approach each other.

As a result of the above, the two rear axles 4°5 perform self-steering as shown in FIG. Also, with this self-steering, the rear first
Displacement occurs between the shaft 4, the rear second shaft 5, and the leaf spring 9, but this is absorbed by the rubber member R, so that no excessive force is applied. Furthermore, when the vehicle turns to the right, self-steering is performed by the opposite effect to the above, and in either case, the vehicle can turn smoothly.

Since the present invention is constructed and operates as described above, in a trunnion-type suspension system that supports two rear axles of a vehicle, which is equipped with a pair of lower torque rods on each side, the lower torque rods have a large size. By providing a tilt angle and inserting a rubber member between the rear two axle axle housings and the leaf springs, when the vehicle tilts while turning, the swing angle of the lower torque rod on the left and right sides of the vehicle is reduced. By utilizing the fact that the rear two axes are different, it is possible to make the rear two axles have a self-steering function with an extremely simple configuration, and as a result, the rear two
The dynamic turning radius of the axle vehicle is reduced to improve the maneuverability of the vehicle, and the reduction in side force reduces wear on the side tires, thereby improving their durability. In addition, internal stress is also reduced, which has the effect of making it possible to design the suspension system to be lighter.

[Brief explanation of the drawing]

The drawings relate to an embodiment of the present invention; FIG. 1 is a side view of a suspension system of a vehicle; FIG. 2 is a schematic diagram of a mechanism showing the operating state of a torque rod on the right side of a vehicle when the vehicle turns to the left; Fig. 3 is a schematic diagram of the mechanism showing the operating state of the left torque rod, and Fig. 4 is a schematic plan view of the two ridge axes, the torque rod, and the wheels, showing the self-steering state when the vehicle turns to the left. . 1 is a vehicle suspension system, 2 is a lower torque rod, 2a, 2
b is the mounting joint, 3 is the trunnion shaft, 4 is the rear first shaft, 5 is the rear second shaft, 9 is the leaf spring, 9a and 9b are one end, 11.12 is the axle housing, R is the rubber member, Δα is the swing angle of the lower torque rod. Patent applicant Hino Motors Co., Ltd. Agent Patent attorney 1) Kazuo 9- Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a trunnion-type suspension system that includes a pair of lower torque rods on each side and supports two rear axles of a vehicle, at least the pair of lower torque rods are arranged such that the attachment joints to the trunnion shafts are located at a high position, and the rear first The axle housing of the rear first shaft and one end of the leaf spring are fixed via a rubber member, and the mounting joint portions for the shaft and the rear second shaft are respectively installed at a lower position, and the axle housing of the rear first shaft and one end of the leaf spring are fixed via a rubber member. The axle housing and the other end of the leaf spring are fixed via a rubber member, so that when the vehicle tilts left and right due to turning, the swing angle of the lower torque rod is fixed to the left and right sides of the vehicle. The first rear axis and the second rear axis are
Self-steering is performed by moving the axles closer to each other on one side of the vehicle and separating them on the opposite side, and the displacement of the two rear axles caused by the self-steering is absorbed by the rubber member. Characteristic vehicle suspension system.