JPH0526279A - Rotary type shock absorber - Google Patents

Abstract

PURPOSE:To control a damping force by means of a friction force by a method wherein viscous oil with which a chamber between a partition wall and a rotor is filled generates an internal pressure, responding to a relative rotation speed, in the chamber through resistance of a throttle passage, and the internal pressure is exerted on a piston through an opening, the area of which is differed with a rotor rotation direction to press a friction clutch. CONSTITUTION:The interior of a housing 1 is axially divided into two spaces by means of a partition wall 13. In the one space, a friction clutch 4 and a press piston 9 are provided. In the other space on the back side of the piston 9, a partition wall 11 is located and chambers S1 and S2 are formed at the front and in the rear in a rotation direction by means of a rotor 12 rotatably located in a rotary shaft 3 and the partition wall 11. The two chambers are intercommunicated through a throttle passage 20 formed in a gap between the outer periphery of the rotor 12 and the inner periphery of the partition wall 11. Holes 14a and 14b and holes 15a and 15b opened to the chambers S1 and S2 and to the back of the piston 9, respectively, and differed in an opening area with size are formed in the partition wall 13. The chambers S1 and S2 are filled with viscous oil. Thus, a difference in a damping force is produced by means of the different friction forces of a friction clutch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shock absorber which damps a rotary rocking force by rotary motion, and is applied to a suspension of an automobile.

[0002]

2. Description of the Related Art As a rotary shock absorber that damps a rotational oscillating force by a rotary motion, for example, an actual open shovel 60-33.
No. 36 is disclosed. This is, as shown in FIG. 4, a partition wall 55 protruding radially from the inner peripheral surface of a cylindrical housing 53 in which hydraulic oil is enclosed, a rotary shaft 57 penetrating the center of the housing 53, and the housing 5
3 and a vane 59 that extends in the radial direction from the rotary shaft 57, and the chamber of the housing 53 is formed by the partition wall 5
It is divided into two chambers by 5 and vane 59. Further, the partition wall 55 is provided with an orifice 63 with a flow rate adjusting valve for communicating between these two chambers.

In the rotary shock absorber, when the rotary shaft 57 rotates, the vanes 59 rotate in the same direction as the rotary shaft 57. As a result, the working oil in the chamber where the volume is reduced is pushed by the vane 59, and the working oil flows through the orifice 63 to the chamber where the volume is increased,
A damping force acts on the rotating force of the rotating shaft 57 due to the resistance at that time. This damping force is adjusted by changing the opening of the orifice 63 by the flow rate adjusting valve 51 and changing the resistance by changing the flow path of the working oil flowing through the orifice 63.

[0004]

In the rotary shock absorber described above, the damping force for the rotational force of the rotary shaft 57 is determined by the pressure generated by the resistance of the hydraulic oil as it passes through the orifice. In order to generate force, the generated pressure is insufficient, and there is a problem in quick responsiveness.

Further, the damping force on the forward rotation side swing (rebound side) of the rotating shaft on the extension side and the damping force on the reverse rotation side (bounding side) of the rotating shaft on the contraction side are the rotation speed of the rotating shaft. Accordingly, as shown in (3) of FIG. 3, a damping characteristic that a large damping force is required on the rebound side as shown by a dotted line C and a damping force difference that is a small damping force is shown on the bounding side as shown by a dotted line D is required. However, in the conventional rotary shock absorber described above, there is no difference in damping force as shown by the solid lines a and b in FIG.

An object of the present invention is to provide a rotary shock absorber capable of generating a large damping force at a relatively low generated pressure and capable of generating a damping force difference between forward and reverse rotations.

[0007]

SUMMARY OF THE INVENTION A feature of the present invention for achieving the above object is to provide a cylindrical housing and a rotatably rotatably mounted bearing inside the housing along its axis. A rotary shaft, a partition wall that divides the housing into two spaces in the axial direction, and a friction clutch that is arranged between the housing and the rotary shaft in the one space and that transmits torque between the housing and the rotary shaft. , Provided with a piston for pressing this friction clutch in the contact direction,
A partition wall provided between the inner wall of the housing and the rotating shaft in the other space on the back side of the piston, and a rotor fixed to the rotating shaft to partition the chamber in the other space. The partition wall is provided with a hole that opens in the chamber partitioned by the rotor and has a different opening area on the back side of the piston, and the chamber partitioned by the rotor is filled with viscous oil. It was done.

[0008]

With the above construction, the viscous oil filled in the chamber between the partition and the rotor is caused to flow inside the chamber between the partition and the rotor due to the flow passage resistance of the viscous oil filled in the chamber between the partition and the rotor due to the relative rotation between the housing and the rotary shaft. Is generated according to the relative rotation speed, and this generated internal pressure is applied to the back surface of the piston through one of the holes with different opening areas provided in the partition wall depending on the rotation direction of the rotor, and the piston that is pushed by this causes the pressure reception The friction clutch is pressed with a pressing force according to the area difference, and the friction force of the friction clutch causes a difference in damping force in the relative rotation direction.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a cylindrical housing, and 1
There is an opening on the side, and the end cap 2 is tightly fitted in the opening. The interior of the housing 1 is partitioned by a partition wall 13 between the side wall of the housing 1 and the partition wall 13 and the end cap 2. It is divided into two spaces between the partition wall 13. A rotary shaft 3 is supported in the housing 1 so as to be rotatable relative to the housing 1 along the axis thereof.

In one of the spaces in the housing 1,
A friction clutch 4 that transmits torque between the housing 1 and the rotating shaft 3 and a piston 9 that controls the friction clutch 4 in the connecting direction are arranged. This friction clutch 4 has a structure in which a plurality of inner plates 6 are provided on the outer circumference of the rotary shaft 3.
Are engaged with each other in the rotational direction by the spline 5 and are arranged side by side so as to be movable in the axial direction. Also, a plurality of outer plates 8 are arranged in parallel with each other on the inner periphery of the housing 1 so as to engage with each other by a spline 7 in the rotational direction and to be movable in the axial direction. The multi-disc clutch structure. The housing 1 in which the friction clutch 4 is arranged is filled with oil for lubricating and cooling the friction clutch 4 and the like.

A piston 9 for pressing the friction clutch 4 in the contact direction is slidably provided on the outer circumference of the rotary shaft 3. Further, the end portion of the friction clutch 4 on the side opposite to the piston 9 side is in contact with the ring member 10 fixed to the housing 1.

The housing 1 is provided in the other space.
A partition wall 11 is provided between the inner wall of and the rotating shaft 3.
The partition wall 11 may project from the partition wall 13 as shown in the figure, or may project from the inner wall of the housing 1. Further, a blade-shaped rotor 12 is rotatably provided on the rotating shaft 3 together with the rotating shaft 3, and the chamber S is provided in the front and rear of the rotor 12 in the rotating direction by the rotor 12 and the partition wall 11.
Partitions 1 and S2 are formed. Room S before and after these
1, S2 are communicated with each other through a limited gap (throttle passage) 20 formed between the outer circumference of the rotor 12 and the inner circumference of the partition wall 11.

Further, the partition wall 13 is provided with holes 14a and 14b which open into the chambers S1 and S2 partitioned by the rotor and which are open to the rear surface of the piston 9. The hole 14a opening to the chamber S1 has a large area opening 15a on the back side of the piston 9, and the hole 14a opening to the chamber S2 is on the back side of the piston 9
The opening 15b has an area smaller than 5a. The chambers S1 and S2 are filled with highly viscous oil such as silicone oil.

The operation of the rotary shock absorber of the present invention having the above structure will be described. Although the housing 1 may be fixed and the rotary shaft 3 may be movable, or conversely, the housing 1 may be movable and the rotary shaft 3 may be fixed. Will be described as the movable side.

As shown in FIG. 2, when a rotational force is input to the rotary shaft 3 at the neutral position of the rotor 7, the rotor 7 rotates in the same direction as the rotary shaft 3 in response to this. Now, in FIG. 2, when the rotor 12 rotates in the clockwise direction RB, the volume of the chamber S1 in front of the rotor 12 in the rotating direction of the rotor 12 is reduced, and the volume of S2 in the rear of the rotor 12 is expanded and changed. The viscous oil in the chamber S1 expands the volume through the throttle passage 20 between the rotor 12 and the partition wall S2.
Flow to. An internal pressure is generated in the chamber S1 by the flow path resistance when flowing from the chamber S1 to the chamber S2, and this acts on the rear surface of the piston 9 through the hole 14a.

The opening 15a on the back side of the piston 9 of the hole 14a has a large opening area, and the pressure receiving force on the back side of the piston 9 is applied in accordance with the large opening area of the opening 15a, so that the friction clutch 4 is opened. Press in the contact direction with a strong force. As a result, it acts on the rotating shaft 3 as a damping force, and as shown by the dotted line C in FIG. 3, a large damping force is obtained in the rebound on the extension side according to the rotation speed of the rotating shaft 3.

Further, in FIG. 2, when the rotor 12 rotates in the counterclockwise direction B, the volume of the chamber S2 in front of the rotor 12 in the direction in which the rotor 12 rotates is reduced, and the volume behind the rotor 12 is reduced. The volume of S1 increases and the viscous oil in the chamber S2 flows through the throttle passage 20 between the rotor 12 and the partition wall 11 into the chamber S1 of which the volume is increased.
Internal pressure is generated in the chamber S2 due to the flow path resistance when flowing from 2 to the chamber S1, and this acts on the back surface of the piston 9 through the hole 14b.

The opening 15b of the hole 14b on the back side of the piston 9 has a smaller opening area than the opening 15a on the side of the hole 14a, and the pressure receiving force on the back of the piston 9 is small in the opening 15b. It is given according to the opening area,
The friction clutch 4 is pressed in the contact direction with a force smaller than that in the case of rotating the rotor 12 in the clockwise direction RB. As a result, as shown by the dotted line C in FIG. 3, a smaller damping force according to the rotation speed of the rotary shaft 3 is obtained in the contraction side bound as compared with the extension side rebound.

The rotary shock absorber according to the present invention having such a damping force difference characteristic between the extension side rebound and the contraction side bounce is applied to various devices for relative displacement, but is applied to an axle suspension of an automobile. In this case, by fixing the housing 1 to the suspension member and connecting the upper arm of the suspension to the rotary shaft 3, it is most suitable as a shock absorber of the suspension for achieving a low floor.

[0020]

As described above, according to the present invention, the viscous oil in the chamber formed between the rotor and the partition wall due to the relative rotation of the housing and the rotary shaft is expanded from the chamber whose volume is reduced through the throttle passage. The internal pressure is generated by the flow path resistance when flowing into the chamber, and this internal pressure activates the friction clutch provided between the housing and the rotating shaft via the piston, and the damping force is generated by the frictional force of the friction clutch. With this configuration, a large damping force can be generated at a relatively low pressure of the viscous oil, and responsiveness can be quickly obtained.

Further, the piston is provided with a pressure receiving area difference in the forward and reverse rotation directions of the rotating shaft, and the friction clutch is pressed with a pressing force corresponding to the pressure receiving area difference, whereby the rotating shaft on the extension side is provided. The damping force on the forward rotation side (rebound side) and the damping force on the reverse side (bound side) of the rotating shaft, which is the contraction side, have a damping force difference according to the rotation speed of the rotating shaft. Realize the characteristics.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

[Fig. 3] Damping force characteristic diagram

FIG. 4 is a sectional view of a conventional rotary shock absorber.

[Explanation of symbols]

 1 Housing 2 End Cap 3 Rotating Shaft 4 Friction Clutch 9 Piston 11 Partition 12 Rotor 13 Partition Walls 14a, 14b Holes 15a, 15b Opening 20 Throttle Passage

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsuge Satoshi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Automobile Co., Ltd.

Claims (1)

Claim: What is claimed is: 1. A cylindrical housing, a rotary shaft that is rotatably supported in the housing by being inserted through the housing along an axis thereof, and the housing is provided with two spaces in an axial direction. A partition wall to be divided, a friction clutch arranged between the housing and the rotating shaft in the one space to transmit torque between the housing and the rotating shaft, and a piston for pressing the friction clutch in a contact direction are provided. A partition wall provided between the housing inner wall and the rotary shaft in the other space on the back side of the piston, and the partition wall fixed to the rotary shaft to partition the chamber into the other space. And a hole having a different opening area is opened in the partition wall, the opening opening to the inside of the chamber partitioned by the rotor, and the opening area opening to the back surface of the piston. Rotary shock absorber, characterized in that filled with viscous oil cut the room.