JPH0488232A - Damping force adjusting device - Google Patents

Abstract

PURPOSE:To simplify the circuit constitution of the control pressure and reduce cost by installing an adjusting means for shifting a flexible valve installed in a flow passage in which working oil flows and allowing the adjustng means to operate as a variable throttle valve, pressure control valve, and a stop valve. CONSTITUTION:When the control pressure introduced into the working pressure chamber 65 of a diaphragm 64 is increased, a rod 59 is pushed into a chamber 40B, receiving the thrust of the diaphragm 64, and the second flexible valve 44 acts as variable throttle valve, and the damping force generated with the approach to a valve seat 45 increases. Further, when the control pressure is increased, the second flexible valve 44 acts as relief valve whose set load varies according to the shift quantity of a rod 59 from the time point of the contact with the valve seat 45, and generates a high damping force. When the rod 59 shifts furthermore, the second flelxible valve 44 acrts as closing valve at the position where the flexible quantity is restricted between the valve seat 45 and a cup 60, and shields the flow of the working oil passing through a hollow bolt 43.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a damping force adjustment device for a vehicle damper.

(Prior art) In a vehicle damper, a relief valve is provided in the passage through which hydraulic oil flows at least on both the compression side and the rebound side, and the set load of the relief valve is changed according to external control pressure. The system not only adjusts damping characteristics to maintain good ride comfort and handling during normal driving, but also generates high damping force for anti-roll and anti-dive control when turning or braking. There is a known device that can do this (Japanese Unexamined Patent Publication No. 13407/1999).

(Problem to be Solved by the Invention) In this case, the set load of the relief valve simply changes in proportion to the control pressure from the outside, and therefore, when the vehicle is turning or braking, it does not change during normal driving. In comparison, it is necessary to significantly change the control pressure supplied to the relief valve, which results in a complicated control pressure circuit configuration, resulting in an increase in the size and cost of the entire device.

This invention aims to solve these problems.

(Means for Solving the Problems) Therefore, the present invention provides a plate-shaped flexible valve movably toward the valve seat in the passage through which hydraulic oil flows at least on the compression side and the expansion side of the damper, and An adjustment means is provided to move this flexible valve in response to external control pressure, and the flexible valve functions as a variable throttle valve in the movement range where it is away from the valve seat, and the set load changes in the movement range where it contacts the valve seat. The pressure control valve is configured to function as a shutoff valve at a position where the amount of flexibility of the valve is restricted.

(Function) The plate-shaped flexible valve moves in response to external control pressure, and its function changes from a variable throttle valve to a pressure control valve with a changing set load, and then to a closing valve, so the control pressure is changed. It is possible to greatly adjust the generated damping force without making a large change.

(Example) In FIGS. 1 to 3, the damper 1 has a piston 22 attached to the tip of a piston rod 21 inserted into a cylinder 20, and defines the inside of the cylinder 20 into two oil chambers 23A and 23B.

An outer tube 24 is concentrically disposed outside the cylinder 20 and forms an annular oil reservoir chamber 25 between the outer tube 24 and the cylinder 20 .

The piston 22 has a check valve 26 that allows hydraulic oil to flow only from the oil chamber 23B to the oil chamber 23A, and the bottom of the cylinder 20 has a check valve 26 that allows the hydraulic oil to flow only from the oil reservoir chamber 25 to the oil chamber 23B. A check valve 27 is provided.

On the other hand, a damping force adjustment valve 3 is provided in the middle of a passage 30 connecting the oil chamber 23A and the oil reservoir chamber 25, and generates a damping force for compression side and rebound side operations by applying resistance to the flow of hydraulic oil. let

That is, during overwhelming operation in which the piston 22 moves downward, the compressed hydraulic oil in the oil chamber 23B flows into the expanding oil chamber 23A via the check valve 26 of the piston 22, and is further increased by the intrusion volume of the piston rod 21. Corresponding hydraulic oil flows out from the passage 30 to the oil reservoir chamber 25, and when the piston 22 moves upward in the expansion side operation, the piston 2
Since the second check valve 26 is closed, the hydraulic oil in the oil chamber 23A to be compressed flows from the passage 30 to the oil reservoir chamber 25, and the check valve 27 at the bottom is used for the expanding oil chamber 23B.
Hydraulic oil is replenished from the oil reservoir chamber 25 via the
Hydraulic oil is supplied to the passage 30 for both compression side and expansion side operation.
The oil is circulated to the oil sump chamber 25 via the
Depending on the resistance of the damping force adjustment valve 3 in the middle of the passage 30, predetermined compression side and rebound side damping forces are generated.

The passage 30 is connected to a port 32 provided in a bearing portion 31 at the upper part of the cylinder 20, and is formed as a conduit passing vertically through the cylinder 20, and the damping force adjustment valve 3 is attached from the outside of the outer tube.

As is clear from FIG. 3, in the damping force adjustment valve 3, both ends of a cylindrical valve body 35 are closed by a cap 36 and a rod guide 37, respectively.

The inside of the valve body 35 is separated by partition members 38 and 39.
It is partitioned into two chambers 40A to 40C, and the partition wall member 38
The passage 41 that communicates 0A and 40B is also connected to the partition member 39.
A passage 42 is formed in which the chambers 40A and 40C communicate with each other.

The partition members 38 and 39 have chambers 40B and 4 extending therethrough.
A hollow bolt 43 is provided to communicate the 0C, and a tapered seat portion 45 is formed at the head of the bolt 43 to face a plate-shaped flexible valve 44 as a second damping valve, which will be described later.

46 connects the chamber 40A inside the pulp body 35 to the oil chamber 23AI.
47 also connects the chamber 40C to the oil sump chamber 25 in the passage 30 of Il.
The through holes connected to the side passages 3o are shown.

The partition member 38 is provided with a plate-shaped flexible valve 48 as a first damping valve that opens and closes the passage 41.
A small notch 50 (orifice) is formed that keeps 9 open at all times.

The first flexible valve 48 is connected to the partition wall member 38 on the outer periphery of the hollow bolt 43.
The spring receiver 52 and the shim 53 are sandwiched between the spring receiver 52 and the spacer 51 to support the inner peripheral portion.

Further, 54 is an overload relief valve that opens and closes the passage 42 of the partition member 39, and is biased against the seat portion 57 by a set spring 56 interposed between the hollow rod 43 outer periphery and a spring receiver 55. 58 indicates a nut that supports the yurt/receiver 55.

On the other hand, the rod guide 37 is provided with a freely slidable rod 59, and a cup 60 is coupled to the tip of the rod 59 that projects into the chamber 40B.

Inside the cup 60, a second flexible valve 44 is mounted on the outer periphery of the cup 60, and the gym 6
It is held between 2 and 2.

The rear end of the rod 59 is connected to the diaphragm 6 via the seat 63.
4, and a control pressure (pilot pressure) that changes depending on the operating state is introduced from the outside into the operating/dynamic pressure chamber 65 of the diaphragm 64. Reference numeral 66 indicates a plug having a pressure guiding port 67 that connects the operating pressure chamber 65 of the external diaphragm 64 to an external control pressure circuit, and 68 indicates a through hole that releases the back pressure chamber 69 of the diaphragm 64 to the atmosphere.

In FIG. 1, a gas chamber 71 partitioned off by a free piston 70 is formed inside the piston rod 21, and the pressure of the oil chamber 23A is introduced to the end surface of the free piston 70, and the damping force adjustment valve 3 is closed. When the load suddenly increases in the locked state, the free piston 70 is displaced,
It is designed to absorb shock.

The system is constructed as described above, and its operation will be explained next.

As the piston rod 21 expands and contracts, hydraulic oil flows from the oil chamber 23A to the oil reservoir chamber 25 via the passage 30 in either direction, and therefore the resistance of the damping force adjustment valve 3 is increased on both the expansion side and the compression side. A damping force is generated according to the

The second flexible valve 44 operates at a position where the rod 59 is pushed out by the biasing force of the balance spring 61 and the cup 60 touches the rod guide 37 when the control pressure guided to the operating pressure chamber 65 of the diaphragm 64 is low pressure. Allow free flow of oil.

At this time, the orifice 50 provides a predetermined damping resistance to the hydraulic oil flowing from the oil chamber 23A to the oil reservoir chamber 25 at the initial stage of operation of the biston rod 21, and the orifice 50
When the differential pressure around 0 exceeds a set value, the first flexible valve 49 opens and generates a damping force according to the amount of deflection.

On the other hand, when the control pressure introduced into the operating pressure chamber 65 of the diaphragm 64 is increased, the rod 59 is pushed into the chamber 40B under the thrust of the diaphragm 64, and the second flexible valve 44 is thereby It functions as a valve and increases the generated damping force as it approaches the valve seat 45.

When the control pressure is further increased, the second flexible valve 44 applies a set load (initial deflection amount of the valve 44 into the cup 60) according to the amount of movement of the rod 59 from the time it contacts the valve seat 45.
It functions as a relief valve that changes the damping force and generates a high damping force.

When the rod 59 moves further, the second flexible valve 44 functions as a shutoff valve at a position where the amount of flexibility is limited between the valve seat 45 and the cup 60, allowing the flow of hydraulic fluid through the hollow bolt 43. cut off.

At this time, when the pressure in the oil chamber 23A exceeds a predetermined value, the overload relief valve 54 opens to release the hydraulic oil into the oil reservoir chamber 25.

Therefore, by adjusting the external control pressure, the damping force adjustment valve 3 changes the damping characteristics as shown in Fig. 4. In addition to adjusting damping force, it is possible to generate high damping force for anti-roll and anti-dive control during cornering and control, for example.

In this case, the second flexible valve 44 moves in response to external control pressure, and the function itself changes from free flow to a variable throttle valve, a relief valve with a variable set load, and a shutoff valve. Therefore, the generated damping force can be largely adjusted without greatly adjusting the control pressure.

In addition, FIG. 5 shows the damping characteristics of the second flexible valve 44, and the second flexible valve 44 has a valve seat 45 in the variable throttle area.
As it approaches the cup 60, it is pushed by the hydraulic oil pressure and bends inward, so the orifice opening (a1 to as
) and the amount of deflection ■ (a, +V2~a, +V
, ) generates a damping force.

(Effects of the Invention) In summary, according to the present invention, a plate-shaped flexible valve is movably provided toward the valve seat in the passage through which hydraulic oil flows on at least one of the pressure side and expansion side operations of the damper, and
An adjustment means is provided to move this flexible valve in response to external control pressure, and the flexible valve functions as a variable throttle valve in the movement range where it is away from the valve seat, and the set load changes in the movement range where it contacts the valve seat. Since it is configured to function as a pressure control valve and also as a closing valve at the position where the valve's flexibility is restricted, it is possible to significantly adjust the generated damping force without significantly changing the external control pressure. Therefore, the effects of simplifying the control pressure circuit configuration and reducing costs can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the entire damper showing an embodiment of the present invention;
FIG. 2 is a circuit diagram, FIG. 3 is a sectional view of the damping force adjusting valve, and FIGS. 4 and 5 are damping force characteristic diagrams. 1... Damper, 3... Damping force adjustment valve, 44...
- Plate-shaped flexible valve, 45... Valve seat, 59... Rod, 61... Balance spring, 64... Diaphragm. Figure 4 Bis ratio smolarity -> Figure 5 Procedural amendment (voluntary) October 22, 1990 Mr. Satoshi Uematsu, Commissioner of the Japan Patent Office (2) 1, Indication of the case 1990 patent application @202283 No. 2, Invention Name of damping force adjustment device 3, relationship with the person making the amendment case Patent issued 1tA. Address: World Trade Center Building, 2-4-1 Hamamatsucho, Minato-ku, Tokyo (092) Kayabae Gyo Co., Ltd. 4, Agent 7, Contents of amendment (1) Amended the "Scope of Claims" of Mei IIIF as attached. do. (2) From the 6th line to the 7th line of page 6 of the specification, the phrase ``the tapered sheet portion 45'' is corrected to ``the sheet portion 45''. (3) From line 14 to line 15 on page 6 of the specification, [66 is for external Guya 7 Ram 64] is replaced with “66
is corrected as ``guiya 7 ram 64''. (4) Figures 1, 2, and 3 of the drawings shall be amended as shown in the attached sheets. 5. Date of amendment order Claim 1: A plate-shaped flexible valve is movably provided toward the valve seat in the passage through which hydraulic oil flows during at least one of Gunpa pressure and expansion side operation, and An adjustment means is provided to move this flexible valve in response to external control pressure, and the flexible valve functions as a variable throttle valve in the movement range where it is away from the valve seat, and the set load changes in the movement range where it contacts the valve seat. A damping force adjusting device characterized in that it is configured to function not only as a pressure control valve but also as a closing valve at a position where the amount of flexibility of the valve is restricted. 2. In the damping force adjustment device installed outside the damper body, the first damping valve and the second damping valve are connected in series, the V41 damping valve and the leaf valve are connected in parallel, and Gunpa's damping valve is used as the second damping valve. Adjustment in which a twisted flexible valve is movably provided toward the valve seat in the passage through which hydraulic oil flows during at least one of the compression side and rebound side operations, and the flexible valve is moved in response to external control pressure. A means is provided, and the flexible valve is used as a variable throttle valve in the movement range where it is separated from the valve seat. A damping force adjusting device characterized in that it is configured to function as a shutoff valve at a position where the damping force is adjusted.

Claims (1)

[Claims] 1. A plate-shaped flexible valve is provided movably toward the valve seat in the passage through which hydraulic oil flows on at least one of the pressure side and rebound side of the damper when the damper is operated, and the flexible valve is operated in response to external control pressure. The flexible valve can be used as a variable throttle valve in the range of movement where it is separated from the valve seat, and as a pressure control valve with a set load that changes in the range of movement in which it contacts the valve seat. A damping force adjusting device characterized in that it is configured to function as a shutoff valve at a restricted position.