JP3833344B2 - Vehicle damper - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle damper having a function of adjusting vehicle height and roll rigidity.
[0002]
[Prior art]
Conventionally, a damper for a vehicle includes a damper main body, a damper rod protruding above the damper main body and movable in the vertical direction with respect to the damper main body, a lower spring receiver attached to the damper main body, and an upper spring receiver connected to the vehicle body. A suspension spring interposed between the upper end of the damper rod and the upper end of the damper rod.
[0003]
There is also known a vehicle damper provided with a drive mechanism for moving the upper spring receiver relative to the vehicle body in the vertical direction so that the vehicle height can be adjusted by the vertical displacement of the upper spring receiver.
[0004]
[Problems to be solved by the invention]
In order to improve the motion performance during high-speed driving, it is necessary to lower the vehicle height and increase the roll rigidity. However, if the upper spring support is displaced up and down relative to the vehicle body, the vehicle height can be lowered. Roll rigidity cannot be increased.
[0005]
In view of the above, an object of the present invention is to provide a vehicular damper that can change roll rigidity in accordance with vehicle height.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is connected to a damper body, a damper rod protruding above the damper body and movable in the vertical direction with respect to the damper body, a lower spring receiver attached to the damper body, and the vehicle body. In a vehicle damper comprising a suspension spring interposed between the upper spring receiver and the upper spring receiver, there is provided a drive mechanism for moving the damper rod in the vertical direction relative to the upper spring receiver and the vehicle body to which the upper spring receiver is coupled . .
[0007]
The damper rod moves upward relative to the damper body due to the upward relative movement with respect to the upper spring receiver. However, when the damper rod moves to the upper moving end position with respect to the damper body, the damper body is pulled up via the damper rod. As a result, the overall length of the damper is shortened and the vehicle height is lowered, and the extension of the damper is restricted. Therefore, the lifting of the vehicle body on the turning inner ring side is suppressed, and the roll rigidity is increased.
[0008]
In this case, if a rebound stopper capable of elastic deformation that is compressed by the upward movement of the damper rod relative to the damper body is provided in the damper body, the damper body is pulled up via the rebound stopper by the upward movement of the damper rod, The extension of the damper is elastically regulated by the rebound stopper. Therefore, the impact at the time of rebound can be absorbed to some extent by the elastic deformation of the rebound stopper.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a twin-tube type hydraulic damper for a vehicle including a damper main body 1 including an inner tube 1a and an outer tube 1b and a damper rod 2 protruding above the damper main body 1.
[0010]
The inner tube 1a is an oil chamber filled with oil, and the inner tube 1a and the outer tube 1b communicate with the oil chamber via a bottom valve (not shown) at the lower end of the inner tube 1a. It is a reserve room. The damper rod 2 is inserted into the inner tube 1a from above, a damper piston 3 is attached to the lower end of the damper rod 2, and the damper piston 3 is placed between the piston upper chamber portion and the piston lower chamber portion of the oil chamber as the damper expands and contracts. Oil is circulated through the formed squeezed hole (not shown), and a damping force is generated by the flow resistance applied by the squeezed hole.
[0011]
A lower spring receiver 4 is attached to the outer tube 1b of the damper body 1, and a suspension spring 6 is interposed between the upper spring receiver 5 and the lower spring receiver 4 connected to the vehicle body.
[0012]
The damper rod 2 is movable relative to the upper spring receiver 5 in the vertical direction by a drive mechanism 7. The drive mechanism 7 meshes with an electric motor 70 mounted on the upper spring receiver 5, a worm 71 connected to the output shaft of the motor 70, and a worm 71 supported in a gear box 72 on the upper spring receiver 5. And a downward cup-shaped gear 74 connected to the worm wheel 73, and an upward cup-shaped connecting member 75 connected to the upper end of the damper rod 2. A spline 75a that engages with the gear 74 is formed on the inner peripheral surface of the connecting member 75, and the inner surface of the lower portion of the cylindrical body 76 that hangs down from the gear box 72 is formed on the outer peripheral surface of the connecting member 75 as shown in FIG. A male screw 75b is formed to be engaged with a female screw 76a formed on the peripheral surface, and the connecting member 75 is rotated by the electric motor 70 via the worm 71, the worm wheel 73, and the gear 74, and the screws 75b and 76a accompanying this rotation are used. The damper rod 2 is moved relative to the upper spring receiver 5 in the vertical direction by the vertical movement of the connecting member 75. The cylindrical body 76 is fitted to the central cylindrical portion of the upper spring receiver 5 via a mount rubber 77.
[0013]
A rebound stopper 10 made of a coil spring is provided in the inner tube 1 a of the damper main body 1 so as to be positioned between a pair of upper and lower rings 8 and 9 that are externally attached to the damper rod 2. The lower ring 9 is supported by a retainer 9 a fixed to the damper rod 2, and the rebound stopper 10 and the upper ring 8 are pushed up via the lower ring 9 by the upward movement of the damper rod 2 with respect to the damper body 1. The rebound stopper 10 is compressed by further upward movement of the damper rod 2 after the upper ring 8 reaches the upper moving end position regulated by the stopper 11 at the upper end of the inner tube 1a, and the extension operation of the damper, that is, The rebound operation is elastically regulated. Note that the rebound stopper 10 is not limited to a coil spring, and may be formed of an elastic body such as a cylindrical rubber as long as it is elastically deformable.
[0014]
Further, a bump stopper 12 made of a cylindrical rubber suspended from the bottom of the cylindrical body 76 is externally inserted on the upper portion of the damper rod 2 protruding above the damper main body 1.
[0015]
Next, the operation of the damper configured as described above will be described. When traveling at high speed, the damper rod 2 is moved upward relative to the upper spring receiver 5 by the drive mechanism 7 from the state shown in FIG. In this case, initially, the damper rod 2 moves upward with respect to the damper main body 1, but when the upper ring 8 is pushed up to the upper moving end position, the damper main body 1 is subsequently moved via the rebound stopper 10 as the damper rod 2 moves upward. Finally, as shown in FIG. 1B, the damper is contracted until the upper end of the damper main body 1 comes into contact with the lower end of the bump stopper 12.
[0016]
According to this, the vehicle height is lowered, the extension of the damper is regulated by the rebound stopper 10, and the shrinkage of the damper is regulated by the bump stopper 12, and the wheel rate is shown by line a in FIG. 4. It will become stronger. Therefore, both the rising of the vehicle body on the inner ring side and the sinking of the vehicle body on the outer ring side during turning are suppressed, and the roll rigidity is increased.
[0017]
During low-speed traveling, the damper rod 2 is moved downward with respect to the upper spring receiver 5 by the drive mechanism 7 to obtain the state shown in FIG. According to this, the damper is extended by the length indicated by L in FIG. 4 by the urging force of the suspension spring 6, and the vehicle height is increased. Further, a gap is formed between the upper ring 8 and the stopper 11, and the wheel rate becomes a value corresponding to the spring rate of the suspension spring 6 until the damper extends by this gap. Therefore, the wheel rate becomes weak as indicated by line b in FIG. 4, and the cushioning property is improved.
[0018]
By the way, the damper rod 2 is rotatably connected to the damper piston 3, and a variable throttle plate that rotates integrally with the damper rod 2 is provided in contact with the damper piston 3 so that the damping force can be varied by rotating the damper rod 2. A damper is known. When the drive mechanism 7 is used, the damper rod 2 rotates when the damper rod 2 moves up and down with respect to the upper spring receiver 5. Therefore, the drive mechanism 7 is applied to the damping force variable hydraulic damper, If the damping force is increased by the rotation of the damper rod 2 given when the damper rod 2 is moved upward, the motion performance during high-speed traveling can be further improved.
[0019]
The drive mechanism 7 is not limited to the above embodiment. For example, as shown in FIG. 3, the drive mechanism 7 may be configured by a hydraulic cylinder 7 a attached to the upper spring receiver 5. In this case, the damper rod 2 is connected to the piston 7b in the hydraulic cylinder 7a, and the hydraulic pressure is input to the upper chamber of the hydraulic cylinder 7a during low-speed traveling, and the damper is applied to the upper spring receiver 5 as shown in FIG. The rod 2 is moved downward. On the other hand, when traveling at high speed, hydraulic pressure is input to the lower chamber of the hydraulic cylinder 7a, and the damper rod 2 is moved upward with respect to the upper spring receiver 5 as shown in FIG.
[0020]
Moreover, although the hydraulic damper is used in the above embodiment, the present invention can be similarly applied to other types of dampers such as a viscous damper.
[0021]
【The invention's effect】
As is apparent from the above description, according to the invention of claim 1, the roll rigidity can be varied together with the vehicle height, the vehicle height can be lowered and the roll rigidity can be increased during high speed running, and the motion performance can be improved. Furthermore, according to the invention of claim 2, it is possible to improve the shock absorption at the time of rebound.
[Brief description of the drawings]
FIG. 1A is a longitudinal sectional view of a first embodiment during low speed travel, and FIG. 1B is a longitudinal sectional view of the first embodiment during high speed travel. FIG. 2 is an enlarged sectional view of a main part of a drive mechanism according to the first embodiment. 3A is a longitudinal cross-sectional view of the second embodiment during low-speed travel, and FIG. 3B is a longitudinal cross-sectional view of the second embodiment during high-speed travel. FIG. 4 is a graph showing wheel rates.
DESCRIPTION OF SYMBOLS 1 Damper body 2 Damper rod 4 Lower spring receiver 5 Upper spring receiver 6 Suspension spring 7 Drive mechanism 10 Rebound stopper

Claims (2)

It is interposed between the damper body, a damper rod that protrudes above the damper body, and is movable in the vertical direction with respect to the damper body, and a lower spring receiver attached to the damper body and an upper spring receiver connected to the vehicle body. In a vehicle damper comprising a suspension spring,
A drive mechanism for moving the damper rod in the vertical direction relative to the upper spring receiver and the vehicle body to which the upper spring receiver is coupled ;
A vehicle damper characterized by that.   The vehicular damper according to claim 1, wherein an elastically deformable rebound stopper that is compressed by upward movement of a damper rod with respect to the damper main body is provided in the damper main body.

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