JPH11280819A - Shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shock absorber which includes a valve for allowing hydraulic liquid to flow in both cases of extension and retraction of a piston rod, and which can change damping characteristics of damping force generated by the valve, in both cases of extension and retraction, independent from each other. SOLUTION: In a hard valve 40, the outer peripheral side part of a leaf valve 82 is bent upward during retraction, and the inner peripheral part of the leaf valve 82 is bent downward. Since a coned disc spring 87 is arranged at the inner peripheral side edge part of the leaf spring 82, the inner peripheral side part is bent overcoming the energizing force of the coned disc spring 87 during retraction. With the provision of the coned disc spring 87, the bend shape of the leaf valve 82 can be hanged during extension without the bent shape thereof being changed during retraction, thereby making it possible to increase the valve opening pressure during extension and to increase the damping coefficient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber including a valve that allows a hydraulic fluid to flow from a high-pressure chamber to a low-pressure chamber during both extension and contraction of a piston rod.

[0002]

2. Description of the Related Art Heretofore, there has been known a shock absorber including a valve which allows a flow of a hydraulic fluid from a high pressure chamber to a low pressure chamber during both extension and contraction of a piston rod. For example, Japanese Utility Model Application No. 61-175188
The microfilm has a cylinder body, a piston that partitions the interior of the cylinder body into two chambers, and increases or decreases the volume of the two chambers with relative movement with respect to the cylinder body, and a piston rod fixed to the piston. A valve that allows the flow of the hydraulic fluid from the higher pressure chamber of the higher pressure to the lower pressure chamber of the lower pressure in the two chambers in both the state where the piston rod is extended and the state where the piston rod is contracted. Shock absorbers are described. The valve included in the shock absorber has an annular plate shape and includes a flexible leaf valve.The leaf valve is supported at an outer peripheral edge during extension of the piston rod. The inner peripheral portion is flexed, and during contraction, the outer peripheral portion is flexed while being supported at the inner peripheral edge. However, in the above-mentioned shock absorber,
The damping characteristics of the damping force generated in the valve cannot be changed only in the other state without being changed in either the elongating state or the contracting state.

[0003] The shock absorber described above is provided with a liquid passage in parallel with the valve, and the flow passage area of the liquid passage can be changed. If the flow path area is reduced, the resistance applied to the hydraulic fluid flowing through the liquid passage increases, and the damping force generated in the shock absorber can be increased.If the flow path area is increased,
The resistance applied to the hydraulic fluid is reduced, and the damping force can be reduced. However, what is changed by changing the flow path area of the liquid passage is the damping force generated in the liquid passage, not the damping force generated in the valve. It is still not possible to change one of the shock absorbers during elongation or contraction and not change the other.

[0004]

[Problems to be solved by the present invention, means of solution, operation and
The present invention has been made in view of the above circumstances.
The challenge is the reduction that occurs in the valve.
To increase the degree of freedom in the design of the damping characteristics of damping force.
Thus, according to the present invention, a shock absorber according to the embodiment described below is provided.
Soba is obtained. Each mode is divided into items and item numbers
And, if necessary, refer to the number of the other section
Describe in the same format. This is only for understanding the present invention.
In order to facilitate the technical features and technical features described in the present invention
And their combinations are limited to the following items
Should not be done. (1) The cylinder body and the inside of the cylinder body
Partitioning chamber and relative movement to the cylinder body
A piston for increasing or decreasing the volume of the two chambers,
And the fixed piston rod and the piston rod
Both extended and contracted states
Pressure from the higher pressure chamber of the two chambers with the higher pressure.
Valve that allows hydraulic fluid to flow to the lower pressure chamber with lower power
Wherein the valve comprises:
A flexible leaf valve, and the piston rod
The above-described reset in either the stretching or the contracting state.
Without changing the shape of the deflection of the valve
Shape changing means capable of changing the shape of the bending in the state
Shock absorber characterized by including
1). The shock absorber valve described in this section is
It is assumed that it has a leaf valve that has flexibility.
The shape of the bent leaf valve is changed by the bent shape changing means.
Therefore, it can be changed separately during extension and contraction.
You. In either state during extension or contraction
Without changing the shape of the deflection of the valve
The shape of the deflection in the state can be changed.
If the shape of the leaf valve deflection changes,
The damping characteristics of the generated damping force naturally change,
The degree of freedom in the design of the decay characteristics can be increased. Book
In the description, the leaf valve is a shock absorber.
Bend at least one time during operation
Should bend during operation of the shock absorber.
It is not necessary. For example, if the piston rod is
Elongate even if it does not bend to a contracted state
Leaf valve if it is bent to the extended state
That's it. In addition, it is seated and separated from the valve seat.
If the above conditions are not met,
Let it be a valve. The bending shape changing means is a shock absorber.
Leaf bar when the operating condition of the bushover is the same
This is a means for changing the shape of the deflection of the lube. Operating status is the same
The shock acting on the shock absorber
If the size is the same, the cylinder
If the magnitude of the relative movement speed to the body is the same,
Applicable. The force acting on the shock absorber is the same
The pressure difference between the high pressure chamber and the low pressure chamber is the same,
In this case, if the bent shape of the leaf valve changes,
Changes the flow rate of the working fluid passing through. That is, shock
The operating speed of the absorber changes, and in the end,
The operating speed corresponding to the same force acting on the absorber changes.
The damping characteristic changes. Show
If the operation speed of the absorber is the same,
The hydraulic fluid flow through the
If the bent shape of the valve changes, the fluid between the high-pressure chamber and the low-pressure chamber
The pressure difference changes and the damping force changes. That is, shock
Since the damping force corresponding to the same operating speed of the busor changes
As a result, the attenuation characteristic changes. Leaf valve
The shape of the bending can be represented by a bending curve, for example.
According to the bending shape changing means, either during elongation or during contraction
The deflection curve in either state is not substantially changed
Thus, the bending curve in the other state is changed. Real
If the deflection curve is not changed, the deflection curve will not
This does not mean that the damping characteristics do not change.
It is a state in which no change appears. The shape of the leaf valve deflection
If changed, the minimum action required for the leaf valve to flex
Changing the force (which may correspond to the valve opening pressure) or damping
Coefficient (movement of piston rod relative to cylinder body)
The amount of increase in damping force with respect to the increase in speed)
Can be These minimum acting force and damping coefficient
Since this is an example of the characteristic, the bending shape changing means
It can also be referred to as further means. Decreases during elongation and contraction
The decay characteristics can be changed independently of each other.
In addition, “changing a bending shape” means that two bending shapes are changed.
When they are superimposed, there will be some deviation,
Means that they do not fit together.
This is a kind of change of the shape. The shape of the deflection, for example,
By changing the bending stiffness of the valve
be able to. Therefore, the bending shape changing means must be
Sex change means may be included. Leaf bal
The flexural rigidity of the valve depends on the material of the leaf valve, heat treatment
Can be changed by changing
Bending shape change described below with respect to paragraphs (2) to (16)
It can also be changed by means. (2) the valve includes a plurality of the leaf valves,
At least one of the plurality of leaf valves
Leaf valve shape changed independently of other leaf valves
Possible and independently modifiable,
The shot according to item (1), which constitutes the bending shape changing means.
A absorber (claim 2). Multiple leaf valves
Change the shape of at least one leaf valve
If the leaf valve whose shape has been changed bends,
Deflected shape, leaf valve whose shape has not been changed
Flexure shape, all leaf valves flex together
In one or two of the bending shapes, etc.
Bending shape is changed, and in other cases the bending shape
Can be kept unchanged. Therefore, the extension
Leaf that bends in either one of the middle and contracting states
Without changing the bending shape of the valve substantially,
The bending shape can be changed in
Without changing the damping characteristics in one state,
It can change that in the state. Leaf
Changing the valve shape involves changing the size of the leaf valve.
Changes, changes in thickness, changes in outer shape, and the like. Leaf bal
If the valve has an annular plate shape,
Furthermore, at least one of the inner diameter and the outer diameter is changed,
When changing the thickness, equalize the thickness of the entire leaf valve.
There are cases where it is changed to one and cases where it is partially changed. Ma
In addition, to change the outer shape, change from circular to rectangular, oval, etc.
Furthermore, change from a flat plate shape to a three-dimensional shape, the inner peripheral edge and the outer
Making one or more notches in the peripheral edge, in the middle
Forming through holes and the shape and size of these notches
Changing the shape and size of the through hole
You. To change to a three-dimensional shape, for example, make a dish or bowl
Steps are formed in the thickness direction, etc.
And forming a curved portion. For example,
Three annular plates with valves stacked in the thickness direction
Leaf valve at one end, including leaf valve
With a through hole in the middle,
The outer diameter of the leaf valve is not large enough to cover the through hole.
In this case, the valve shown in FIG. 27 is obtained.
Change the leaf valve to be dish-shaped, and
Is formed, the valve shown in FIG. 34 is obtained. Described in this section
The leaf shape changing means is
included. (3) the valve includes two leaf valves,
One leaf valve overlaps the other leaf valve
The other leaf valve.
The shape does not change the shape of the one leaf valve
Changeable, and that the change is possible
The system described in (1) or (2), which constitutes the shape changing means
Shock absorber. For the shock absorber described in this section
For included valves, either during extension or contraction
In one state, the two leaf valves flex and the other
In the condition of one of the leaf valves
Can be. In this case, the other leaf valve
If one of the leaf valves bends if the shape is changed
Without changing the shape of the two leaf valleys
The bending shape in the case where the valve bends can be changed. This section
The bending shape changing means described in (1) is the weight of the two leaf valves.
Referred to as superimposed shape changing means for changing the shape of the tatami mat
Can be. (4) The valves are generally in the shape of a circular plate and are mutually
Two leaf valves with different ease of bending, and those two
Inner circumference of the leaf valve that is hard to bend
On either side of the side
Upper support member to support from below, lower side to support from below
A supporting member and a leaf valve which is easy to bend.
The edge on one side of the leaf valve is
Is disposed in a state of being overlapped with the edge on one side, and the upper side
Change the shape of either the support member or the lower support member.
By changing the leaf valve,
The shape can be changed, and the changeable
Any of the above items (1) to (3) that constitute the bending shape changing means
The shock absorber according to any one of the above. The system described in this section
The valves included in the shock absorber have different flexing easiness.
Two leaf valves partially overlap each other in the radial direction.
It is arranged in a state of being twisted. Leaf bar with less bending
The lube is located on the inner circumference side, and the leaf valve
If it is located on the circumferential side, the leaf valve that is less likely to bend
The inner peripheral edge has an upper support member and a lower support member.
Supported from both sides by its outer peripheral edge and flexing
The inner edge of the easier-to-use leaf valve is overlapped
It is arranged in a state. Also, the leaf valve, which is hard to bend,
The leaf valve that is located on the peripheral side and
When installing, the leaf valve which is hard to be bent is
Edges of the upper and lower support members
Side, and the inner edge of the
The valve is arranged in a state where the outer peripheral edge of the
It is. In this valve, either during extension or contraction
In either state, the inner circumference of the two leaf valves
Side and outer peripheral side are both bent on the same side.
In the other state, the different parts
Each bends separately. The leaf valve, which is hard to bend, is on the inner circumference
If it is located, the two
The portion on the outer peripheral side of the leaf valve is bent together. The more flexible
The leaf valve is a leaf valve whose inner edge is hard to bend.
The portion on the outer peripheral side bends in a state of being pressed against the bush. Difficult to bend
The inner edge of the leaf valve has an upper support member.
Pressed against one of the upper and lower support members
Is based on the hydraulic pressure difference that acts on itself
Force and the force applied by the more flexible leaf valve
Therefore, it bends. As a result, the two leaf valves are difficult to bend.
The upper support member and the lower support part of one leaf valve
With one of the outer ends of the material as a fulcrum
The opening amount of the valve is almost two leaf bars.
It is the sum of the amounts of deflection of the lubes. On the other hand,
In one state, the inner circumference of the leaf valve
Side part and the part on the outer peripheral side of the leaf valve that is hard to bend.
Bend separately. The leaf valve, which is hard to bend, is
One of the holding member and the lower supporting member opposite to the above one
Is bent with the end on the outer peripheral side as a fulcrum. The hydraulic fluid flow is
Easy-to-read leaf valve and hard-to-bend leaf valve
Is allowed in the gap between. If the opening of the valve is
This is the difference between the amount of deflection of each of the two leaf valves.
You. In this valve, an upper support member and a lower support
The shape of one of the support members (the outer peripheral end
Change the outside diameter of the other, and do not change the shape of the other support member
In such a case, the outer peripheral portion of the leaf valve
Length between one end of the supporting member on the outer peripheral side (fulcrum)
Only the length is changed, but the outer peripheral end of the other support member
And the length between them will not change. As a result, deflection
Difficult leaf valve is a supporting part whose shape has been changed
The amount of bending when bending to the material side (up or down)
When it is bent to the support member side where the shape has not been changed
Will not be changed. Open valve
When the displacement is approximately the sum of the deflections of the two leaf valves.
The amount of deflection in either case
The deflection in the other case will be changed
In either the elongating or contracting state.
Without changing the shape of the bending
It is possible to change the shape of the sole. For example, 2
When the two valve leaves are bent together, the direction is upward and separate
When the direction of flexing is downward,
Change the shape of the upper support member without changing the shape of the member
If the leaf valve, which is hard to bend, bends upward,
The amount of deflection has changed, and the amount of deflection
Absent. As a result, the same side of the two leaf valves flexes together.
The amount of flexure when bending is changed, but the flexure when flexing separately
The amount is almost the same, and two leaf valves
With almost no change in the shape of the flexure when flexing separately,
It is possible to change the shape of the bending when bending together.
You. When the shape of the lower support member is changed, it bends downward
Only the amount of deflection is changed, and two leaf valves are separately
Only the shape of the flexure when flexing is changed. Where the upper
Of either one of the support member and the lower support member
When changing the shape, make the outer periphery of the support member larger.
Or make it smaller. Larger outer circumference of support member
In other words, the outer edge and fulcrum of the leaf member that is less likely to bend
Because the distance between and becomes small, the amount of bending becomes small,
The smaller the outer circumference, the larger the distance between the fulcrum
Therefore, the amount of deflection increases. Deflection of leaf valve
The shape of the part is considered to be the substantial shape of the leaf valve
For example, the bending shape changing means described in this section includes
Similarly, a means for changing the shape of the leaf valve is included.
The support valve shape changing means is included in the valve shape changing means.
Can be considered. Leaf valve which is hard to be bent is outside
Similarly, if it is installed in a position on the circumferential side,
Easily bends during either long or contracting
Between the leaf valve and the leaf valve
The peripheral part bends together, and easily bends in the other state
Outer peripheral part of one leaf valve and leaf that is hard to bend
The inner peripheral portion of the valve bends separately. Leaf that does not bend easily
The outer peripheral edge of the valve has an upper support member and a lower support member.
It is supported from both sides by the holding member, and in any state
One of the upper support member and the lower support member
The inner peripheral part is bent around the inner peripheral end of
become. Therefore, the upper support member and the lower support member are not connected.
The shape of the other support member (the inner diameter of the inner peripheral end)
If it is changed, it may be bent toward the support member whose shape has been changed.
Only the inner part of the leaf valve which is hard to bend
The length between the fulcrum and the fulcrum can be changed, changing the amount of deflection
can do. (5) The valve is a plurality of valves stacked in the thickness direction.
Leaf valve, and of these multiple leaf valves
Is located on the outermost side on either side in the thickness direction
The thickness of the leaf valve excluding the leaf valve
Including the outermost leaf valve on the other side
Through holes in the thickness direction can be formed in one or more leaf valves
And the through-hole can be formed.
Any one of paragraphs (1) to (4) that constitute the state changing means
The shock absorber according to any one of the above. In the above valve
Is located on the outermost side of either side in the thickness direction
No through hole is formed in the leaf valve, but the other side
One or more leads, including the outermost leaf valve
A through hole can be formed in the valve. Shaped through hole
A leaf valve that is not formed is called a main flexure leaf valve,
A leaf valve with a through hole is used as an auxiliary bending leaf valve.
Is called a bus. The valve has multiple auxiliary bending leaf valves
If included, these multiple auxiliary flexure leaf valves
Are connected to each other through the through holes
Can be stacked. The impulse path is composed of a set of these through holes
And the hydraulic pressure in the other chamber is increased
The other side of the lube (with one or more main flex leaf valves)
Other than the main flexible leaf valve located on the other side of
And abbreviated hereinafter. )
Works. In contrast, one of the main flex leaf valves
The hydraulic pressure of one side chamber acts on the side surface. This state
At the other side of the main flexible leaf valve
Hydraulic pressure acting on one side
Hydraulic pressure difference required for main deflection leaf valve to bend (valve opening
Pressure), all main deflection leaf valves are
Bendable. Also, the surface on one side of the main flex leaf valve
Pressure acting on the other side of the auxiliary flexure leaf valve
The difference between the hydraulic pressure acting on the surface is the main deflection leaf valve and the auxiliary
All leaf valves, including bent leaf valves, bend
If the pressure difference is larger than necessary,
The valve will flex. Change the total number of leaf valves
If the number of main deflection leaf valves is changed
The same as changing the number of leaf valves)
The bending shape of the leaf valve when it is bent is almost unchanged.
By changing the bending shape when the bending leaf valve bends
Wear. As a result, the state of either
Without changing the bending shape in the other state,
The bending shape can be changed. The impulse passage has an axial cross section
Small area and large area even if the shape is uniform in the direction
Part (large diameter part and small diameter part if the cross-sectional shape of the through hole is circular)
The main deflection leaf may be
The area adjacent to the valve should have a large area.
No. In this way, the main flexure leaf valve is connected to the other chamber.
This is because the hydraulic pressure can be favorably applied. Cross section of impulse line
Product determines the shape of flexure during elongation and contraction
Can be When the cross-sectional area is uniform and the area is large
When the hydraulic pressure in the other chamber is higher than the hydraulic pressure in one chamber
Is large even if the operating speed of the shock absorber is low
Even if only the main bending leaf valve is bent, the hydraulic pressure in one chamber
Is higher than the hydraulic pressure in the other chamber,
The lube and the main flex leaf valve flex together. The other room
If the hydraulic pressure in one chamber is higher than the hydraulic pressure in one chamber,
Hydraulic pressure is led through the pressure path and the other of the main flexure leaf valve
Acts on the side of the side. Main bending leaf valve is bent to guide pressure
Hydraulic fluid flows in the passage, but the cross-sectional area of the impulse passage is large.
Is allowed to flow at a sufficient flow rate
Therefore, there is a substantial hydraulic pressure difference on both sides of the auxiliary bending leaf valve.
No, the auxiliary flex leaf valve does not flex. What
The main flexible leaf valve is located above the upper part of the two chambers.
Even if it is located on the room side,
May be used. On the other hand, the impulse
And a portion adjacent to the main flexible leaf valve
In the case of a shape having a large area part,
The number of flexures is determined by the position where the small area portion is formed.
When the hydraulic pressure in the other chamber is higher than the hydraulic pressure in one chamber
Is, when the operating speed of the shock absorber is low,
Only the main bending leaf valve is bent, and the operating speed is high.
Then, the auxiliary bending leaf valve in which the small area portion is formed
And an auxiliary flexible leaf valley located on one side thereof
Bu also bends. As the operating speed increases, the flow of hydraulic fluid decreases.
Since the flow is suppressed in the area,
I can't do that. Therefore, before and after the auxiliary bending leaf valve
A hydraulic pressure difference occurs in the valve and the auxiliary bending leaf valve also bends.
Because In this state, the main flex leaf valve
Flexible leaf valve having a small area portion and
The auxiliary bending leaf valve located on one side
It is. As described above, the leaf valley in which the small area portion is formed
If the operating speed is high by changing the position in the thickness direction of the
Changing the number of leaf valves that are deflected in
Thus, the bending shape can be changed. What
In this section, through-hole forming means, through-hole shape change
Means, etc., correspond to the bending shape changing means.
It can also be referred to as a number changing means. (6) The leaf valve has a generally annular plate shape.
Yes, said valve, its annular plate-shaped leaf valve,
Intermediate support for support at an intermediate position between the inner and outer edges
A member of the leaf valve, from the intermediate support member.
The shape of the part on either one of the outer peripheral side and the inner peripheral side
It can be changed, and its shape can be changed,
(1) to (5) of the bending shape changing means.
The shock absorber according to any one of the claims (claim
3). The leaf valve is located between its inner and outer edges
The position is supported by the intermediate support member. So
Here, in one of the states of stretching and contracting
One of the inner part and the outer part
Part is bent, and in the other state, the part on the other side
Can be deflected between the inner and outer sides
If you change the shape of either side of the
The bending shape in either one of
Change the bending shape in the other state with little change
Can be changed. For example, the outer diameter and inner
By changing either one of the diameters, the intermediate support of the bent part
You can change the distance from the member (distance from the fulcrum)
Change the bending shape when one side is bent.
Can be. The intermediate support member is located outside the leaf valve.
One of the peripheral side and the inner peripheral side is
Provided in a state where it can bend with little effect of the part
Is desirable. For example, the intermediate support member is
Material and an upper supporting member, and a ring-shaped leaf
Supporting the middle part of the valve with it sandwiched from both sides
That is. In this way, the intermediate support member
Therefore, the leaf valve is divided into an outer peripheral portion and an inner peripheral portion.
And can be flexed independently.
Wear. In this case, the intermediate supporting member is separated
It can be referred to as a step, an intermediate portion fixing means, or the like. Also,
The valve is positioned midway between the inner and outer rims.
Is divided into two annular plate-shaped leaf valves.
Supported by the intermediate support member in the split position.
In this case, the same effect can be enjoyed. Book
In the paragraph, the inner and outer peripheral side shape changing means
It can also be considered that a state changing means is configured. (7) The leaf valve has a generally annular plate shape.
Yes, said valve, its annular plate-shaped leaf valve,
Any of the two chambers at the outer periphery thereof
Outer peripheral valve seat supported from one chamber side and inner peripheral edge of it
Including an inner peripheral valve seat supported from the other chamber side,
Either the outer peripheral side valve seat or the inner peripheral side valve seat has a shape.
It can be changed, and its shape can be changed,
(1) to (6) of the bending shape changing means
The shock absorber according to any one of the claims (claim
4). Changing the shape of the valve seat may cause the leaf valve to bend.
The position of the fulcrum can be changed and the bending shape can be changed
can do. Edge on the outer peripheral side during extension and contraction
When the inner part is bent while the outer part is supported by the outer valve seat
When the inner peripheral edge is supported by the inner peripheral valve seat.
Since the circumferential part may bend, the inner valve seat and the outer
If the shape of either of the side valve seats is changed,
With little change in the bending shape in the other state.
The bending shape in one of the states can be changed. Re
Deflection on either the outer or inner circumference of the valve
If the distance between the support and the fulcrum is large,
It becomes easy to bend. As the shape of the valve seat flexes
The fulcrum of the leaf valve is changed to move. fulcrum
When it is formed so as to approach the bent part as it bends
In the meantime, the leaf valve becomes difficult to bend as it bends. This section
In the above, the bending shape changing means by the valve seat shape changing means
Although a step is configured, the valve seat shape changing means includes a leaf valve.
Fulcrum moving means. (8) The leaf valve has a generally annular plate shape,
Either during extension or contraction of the piston rod
In the state, the part on the inner circumference side is bent, and in the other state
An outer peripheral portion is bent, and the bent shape changing means is
However, the inner peripheral part and the outer peripheral part of the leaf valve
Deflection suppressing portion for suppressing deflection of a portion on either side of
The material according to any one of paragraphs (1) to (7),
A shock absorber (claim 5). By the deflection suppression member,
Either the inner or outer part
Minute bending is suppressed. Therefore, the part on one side is bent.
The valve opening pressure is increased and the damping coefficient is increased.
Is changed. As a deflection suppressing member
For example, the direction of deflection of one side of the leaf valve
And an elastic member that applies a biasing force in the opposite direction.
You. Due to this elastic member, the portion on one side is not easily bent.
However, the other side does not become difficult to bend. this
If the valve is bent on one side, open it.
Both the valve pressure and the damping coefficient will be changed. Deflection
The restraining member also reverses direction when the leaf valve begins to flex.
Not to be applied, but to be applied as it bends
It can also be. In this case, the valve opening pressure does not change.
However, the damping coefficient is changed. (9) The valve is a hydraulic pressure in a first chamber of the two chambers.
Is higher than the fluid pressure in the second chamber, and does not
One-leaf leaf valve group including one or more leaf valves
And when the hydraulic pressure of the first chamber is higher than the hydraulic pressure of the second chamber.
Bi-flexure including one or more leaf valves that flex even when low
Leaf valve group, these one-sided leaf valve group and both-sided bending
Between these two groups.
An intervening portion having a flow path for supplying the hydraulic fluid in the second chamber
Material, and the shape of the interposed member can be changed,
The bending shape changing means may change its shape.
In any one of paragraphs (1) to (8)
The shock absorber described above (Claim 6). Double flex leaf bar
Between the lube group and the one-sided bent leaf valve group
The working fluid in the second chamber is supplied via the flow path. Double deflection Lee
In the valve group, the surface on the side where the interposed member is provided
The hydraulic pressure in the second chamber acts, and the hydraulic pressure in the first chamber is applied to the opposite surface.
Works. The hydraulic pressure in the second chamber is greater than the hydraulic pressure in the first chamber,
Higher than the hydraulic pressure difference (valve opening pressure) required for the valve group to bend
When this happens, the two bent leaf valve groups bend. For it
Therefore, in the single bending leaf valve group, the surface on either side
Since the hydraulic pressure of the second chamber also acts on the
The leaf valve group does not bend. The hydraulic pressure in the first chamber
Are higher than the hydraulic pressure in the second chamber, these hydraulic pressure differences are:
Both double bent leaf valve group and single bent leaf valve group
If the leaf is larger than necessary to deflect, all leaves
The valve flexes. By changing the shape of the intervening member,
By changing the channel area and the thickness of the intervening member,
Double bending leaf when the hydraulic pressure is higher than the hydraulic pressure in the first chamber
Changing only the bent shape of the valve group or the hydraulic pressure in the first chamber
Two leaf valves when higher than the hydraulic pressure in the second chamber
Only the bending shape of the group can be changed. Channel
The area of the aperture is large enough to have an aperture function.
It may be a size that does not have
The moving speed of the stone rod relative to the cylinder is high.
In the case, the double-flex leaf valve group and the single-flex leaf valve group
And the flow path resistance of the hydraulic fluid between
Due to the change, both bent leaf valve groups are bent
It is possible to change the damping characteristic of the motor. Also,
Thickness of interposed member (part interposed between both leaf valve groups)
The thickness of the leaf valve group can be increased by increasing the
Weight becomes large and resists the set load of the double-flex leaf valve group.
To adjust the valve opening pressure when the two bent leaf valve groups are bent.
Can be larger. With both flow paths kept constant,
So that the thickness of the part sandwiched between the valve groups changes.
If the shape of the existing members is changed, only the two-flex leaf valve group
Without changing the bending shape when
The bending shape in the case of bending can be changed.
Also, the thickness of the part sandwiched between the leaf valve groups
Of the intervening member so that the flow path area changes while
Changing the shape changes the bending shape when the two groups bend.
When only the double-leaved leaf valve group is bent without any further changes
Can be changed. Note that one-sided deflection
The valve and the intervening member, the deflection suppressing member according to the above mode (8).
Can be considered. The bending suppression member
When the hydraulic pressure in one chamber is higher than the hydraulic pressure in the second chamber,
Only the leaf valve group becomes difficult to bend. In contrast, intervening
If the area of the flow path of the member is sufficiently large, the hydraulic pressure of the second chamber
Leaf valleys when the pressure is higher than the hydraulic pressure in the first chamber
The shape (damping characteristic) of the bending of the group of members is controlled by the bending suppressing member.
It will not be changed. (10) The intervening member is one of the two leaf valve groups.
A spacer portion interposed therebetween, and a diametrical position of the interposed member.
And a positioning part to determine the position.
Quasorber. The leaf valve is shaped like an annular plate
In some cases, the intervening member is also annular, for example,
It can be provided on the outer peripheral side of the leaf valve. Intervening member
The positioning part that determines the diametrical position of the
It is effective as a positioning means in the case. (11) The positioning portion is provided for the plurality of leaf valves.
By engaging at least one of the outer peripheral surfaces,
Concentric positioning of at least one of the intervening members
(10) The shock absorber according to the above (10). (12) The positioning portion is provided with the at least one lead
An annular portion having an inner peripheral surface that can be fitted to the outer peripheral surface of the valve
The shock absorber according to item (11), wherein Of the annular part
If the inner peripheral surface is fitted with the outer peripheral surface of the leaf valve, an annular part
Can be positioned in the diameter direction of the
If the spacer part is projected radially inward from the
Position the spacer part in the diameter direction with respect to the leaf valve
can do. (13) Interposition having the spacer portion and the annular portion
The flow path was formed in a state of penetrating the member in the radial direction
The shock absorber according to (12). (14) The spacer portion is located radially within the annular portion.
Item (13), which is a plurality of inward projections protruding in the direction
The shock absorber according to the above. Multiple inward projections etc.
It is desirable to be provided at angular intervals. (15) At least a part of the spacer portion is the annular shape
Offset in the direction parallel to the center line of the annular part
And the hollow surrounded by the shifted part and the annular part
The shock absorber according to (14), wherein the flow path is formed.
Ba. Reduce the deviation of the spacer from the annular part, and
Or, if the distance between adjacent spacers is reduced,
The product can be reduced. In this embodiment, the spacer portion
Suitable when the thickness is small.
The entire spacer is located inside the annular part.
And at least penetrate the annular part in the radial direction.
Also form one through hole and use that through hole as a flow path.
Both are possible. Instead of the through hole,
Surface from the outer edge to the inner edge
It is also possible to form a groove to form a flow path. (16) The double bent leaf valve group and the single bent leaf
An end on the side where the interposed member is interposed with the valve group;
Has a spacer between the opposite ends (No. 9)
(15) The shock absorber according to any one of the above (15).
For example, a double-flex leaf valve group and the single-flex leaf valve
Group includes a leaf valve having an annular shape,
Material is interposed between the outer peripheral sides of both leaf valve groups
In such a case, the spacer is interposed between the inner peripheral side portions.
If a spacer is interposed, both leaf valve groups of interposed members
While increasing the thickness of the spacer section sandwiched between
The amount of deflection of the valve group can be reduced. In this section
In the shock absorber described,
The lube group is the thickness of the spacer and the spacer part of the interposed member.
Be assembled in a state of being bent by the amount corresponding to the difference
Because it becomes. Separate the spacer and intervening member
Alternatively, they may be integrally configured. (17) Two cylinder bodies and two cylinder bodies
And move relative to the cylinder body
Pistons that increase or decrease the volume of these two chambers
And its fixed piston rod and its piston rod
Both the state in which the arm is extended and the state in which it is contracted
In which the higher pressure chamber of the two chambers has the higher pressure
To allow the flow of hydraulic fluid to the lower pressure chamber with the lower pressure.
A shock absorber comprising:
Is either during expansion or contraction of the piston rod.
A state in which the damping characteristic in one state is kept almost constant
In the other state, the attenuation characteristic can be changed
Shock absorber characterized by including changing means
(Claim 7). The shock absorber described in this section
Characteristics during elongation or contraction.
While maintaining the characteristic almost constant, damping in the other state
Properties can be changed. (18) The valve is a leaf valve having flexibility.
Wherein the attenuation characteristic changing means includes the (1) to (16).
Item 1 includes at least one of the bending shape changing means described in (1).
The shock absorber according to the item 7). The shot described in this section
In the absorber, it is generated at the valve
The characteristic of the damping force is changed by changing the bent shape of the leaf valve.
Changed. (19) Two cylinder bodies and the inside of the cylinder body
And move relative to the cylinder body
Pistons that increase or decrease the volume of these two chambers
And its fixed piston rod and its piston rod
Both the state in which the arm is extended and the state in which it is contracted
In which the higher pressure chamber of the two chambers has the higher pressure
To allow the flow of hydraulic fluid to the lower pressure chamber with the lower pressure.
A shock absorber comprising:
However, the differential pressure between the high pressure chamber and the low pressure chamber is equal to or higher than the valve opening pressure.
When the flow of the hydraulic fluid is allowed,
First, the valve opening pressure at the time of extension during the extension of the piston rod
Opening pressure ratio, which is the ratio between the valve opening pressure during contraction and the valve opening pressure during contraction
Valve opening pressure ratio changing means capable of changing the pressure
Shock absorber (Claim 8). The shot described in this section
In the case of the absorber, the valve opening pressure during extension and the valve opening pressure during contraction
Can be changed. Opening a valve
The pressure ratio is one of the valve opening pressure during extension and the valve opening pressure during contraction.
Can be changed by changing only
You. When changing both the valve opening pressure during extension and the valve opening pressure during contraction
Either the valve opening pressure during extension or the valve opening pressure during contraction
Change the other to change the valve opening pressure
And both valve opening pressures may be changed separately. (20) The valve is a leaf valve having flexibility.
Wherein the valve opening pressure ratio changing means includes the above (1) to (16).
Item 1 includes at least one of the bending shape changing means described in (1).
The shock absorber according to the item 9). The shot described in this section
In the case of the absorber, the valve opening pressure ratio
It can be changed by changing the bending shape of the valve. (21) Two cylinder bodies and the inside of the cylinder body
And move relative to the cylinder body
Pistons that increase or decrease the volume of these two chambers
And its fixed piston rod and its piston rod
Both the state in which the arm is extended and the state in which it is contracted
In which the higher pressure chamber of the two chambers has the higher pressure
To allow the flow of hydraulic fluid to the lower pressure chamber with the lower pressure.
A shock absorber comprising:
Moves relative to the cylinder body of the piston rod.
If the dynamic speed is the same,
Elongated damping force generated and generated during contraction
Damping that can change the damping force ratio, which is the ratio with the contracting damping force
Shock absorber characterized by including power ratio changing means
(Claim 9). Piston rod against cylinder body
Elongation damping force and contraction for the same relative movement speed
The damping force ratio, which is the ratio to the time damping force, is
Change the damping coefficient or change the valve opening pressure.
You can change it. Either during extension or contraction
Even if the damping characteristic and valve opening pressure in either
These may be changed. Damping force ratio changing means,
For example, the bending shape change described in the above items (1) to (16)
May include at least one of the additional means,
In this case, the damping force ratio changes in the bent shape of the leaf valve.
Will change. (22) Two cylinder bodies and two cylinder bodies
And move relative to the cylinder body
Pistons that increase or decrease the volume of these two chambers
And a piston rod fixed thereto, and a high-pressure chamber and a low-pressure chamber in which the pressure of the two chambers is higher.
When the hydraulic pressure difference between the low pressure chamber and the
Valve that allows the flow of hydraulic fluid from the chamber to the low-pressure chamber
And whether the pressure difference between the high pressure chamber and the low pressure chamber is small
A soft valve that allows the flow of hydraulic fluid,
Hardware with throttle function provided in parallel with the load valve
The shock absorber includes a valve bypass passage.
And at least one of the hard valve and the soft valve
The more the piston rod is expanded and contracted
In both the state and the
It allows the flow of hydraulic fluid to the low pressure chamber, and
Either during extension or contraction of the piston rod
The bent shape of the leaf valve in the state of
Flexible shape that can change the shape in the other state without changing
Shock absorber characterized by including a shape changing means.
Ba. If the force acting on the shock absorber is small,
Made via hard valve bypass passage and soft valve
Fluid flows, but if the acting force is large, some
Hydraulic fluid flows through hard and soft valves
Will be. The above-mentioned bending shape changing means is provided by a hard valve.
And at least one of soft valves
Wear. At least one of a hard valve and a soft valve
As described in any one of the above items (2) to (16).
It can be a valve. (23) Both the hard valve and the soft valve are:
In both the extended state and the contracted state of the piston rod,
To allow the flow of the hydraulic fluid from the high pressure chamber to the low pressure chamber.
And the hard valve and the soft valve
Are each one of the two chambers of the piston.
Provided on one side of the other room and on the side of the other room
The hard valve bypass passage is provided with the piston
And the hard valve is provided therein.
Side chamber and between the hard valve and the soft valve
The shock absorber according to item (22), which is open to the liquid passage of
Sorva. Hard valve and soft valve are both pistons
Because it is provided on the side, the size of the piston can be reduced
Can be.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a shock absorber according to an embodiment of the present invention will be described in detail with reference to the drawings. This shock absorber is claimed in claims 1, 5, 7-9.
This is one embodiment common to the embodiments. The shock absorber is one of the components of the suspension. As shown in FIG. 3, the cylinder body 10 of the shock absorber is attached to the wheel member 12 via a bracket, and the piston rod 14 is attached to the vehicle body member 16. Further, the spring 18 is disposed between the upper seat 22 and the lower seat 20 attached to the cylinder body 10.

As shown in FIGS. 1 and 2, the shock absorber includes the cylinder body 10, the piston rod 14, the piston 28, the damping force control device 30, and the like.
The piston rod 14 penetrates through the piston 28, and is fixed at its end by a nut, so that the piston 28 and the piston rod 14 can be integrally moved. The piston 28 is liquid-tight and slidable with respect to the cylinder body 10, and the interior of the cylinder body 10 is partitioned into a lower chamber 34 and an upper chamber 36 by the piston 28.

The damping force control device 30 includes a hard valve 4
0, a soft valve 42, a variable throttle device 44, and the like. A hard valve 40 is provided on the lower chamber side of the piston 28, a soft valve 42 is provided on the upper chamber side, and an intermediate liquid passage 46 is provided between the hard valve 40 and the soft valve 42. Also, the piston rod 14
Is provided with a through hole 48 extending in the axial direction and having an opening in the lower chamber 34, and a spool 50 is slidably disposed in the through hole 48. A plurality of radial holes 52 extending in the radial direction are formed in a portion of the piston rod 14 corresponding to the intermediate liquid passage 46, so that the intermediate liquid passage 46 and the through hole 48 communicate with each other. Through hole 48,
The lower chamber 34 and the intermediate liquid passage 46 are connected by a radial hole 52 bypassing the hard valve 40. Lower chamber 34 of through hole 48 provided in piston rod 14
A hard valve bypass passage 54 is formed by the portion between the fluid passage 46 and the intermediate liquid passage 46, the radial hole 52, and the like.
The opening area of the radial hole 52 is controlled as the spool 50 moves in the axial direction, so that the flow area of the hard valve bypass passage 54 is controlled.

The variable throttle device 44 is provided with the spool 50
And a moving device 56 for moving the spool 50 in the axial direction. The moving device 56 includes an electric motor 60.
And a motion conversion mechanism 62 that converts the rotational motion of the electric motor 60 into a linear movement in the axial direction, and a shaft 64 that is movable in the axial direction. The rotation of the electric motor 60 is converted by the motion conversion mechanism 62 into axial movement of the shaft 64, and the axial movement of the shaft 64 causes the spool 5
0 is moved in the axial direction. As described above, in the present embodiment, the hard valve 40, the soft valve 42, and the hard valve bypass passage 54 are provided in the piston 28, and the variable throttle device 44 that controls the flow passage area of the hard valve bypass passage 54 includes the piston rod 14 is provided inside. In the middle of the piston rod 14,
In addition, a rebound stopper 70 is attached, and the extension limit of the piston rod 14 is defined.

As shown in FIG. 4, the hard valve 40 includes a valve seat 80 provided at a lower portion of the piston 28, a leaf valve 82 having an annular thin plate shape, and a leaf valve 82.
, A positioning member 84 for determining the radial position of the leaf valve 82, an intermediate sheet member 86 for supporting the leaf valve 82 from the intermediate liquid passage side, and an annular plate as a deflection suppressing member And a coned disc spring 87. By the positioning member 84, the leaf valve 82
It can be supported concentrically and coaxially. Intermediate sheet member 8
6 is in contact with the piston body via a spacer 88 so that a differential pressure acting force corresponding to a differential pressure between the lower chamber 34 and the intermediate liquid passage 46 applied to the leaf valve 82 can be received. Have been. The piston 28 has an annular groove 9
A plurality of liquid passages 91 are formed to connect the groove 90 to the lower chamber 34, and the outer peripheral edge of the groove 90 is a valve seat 80 as a chamber-side seat. As a result, the upper surface 92 of the leaf valve 82 is
6 and the lower surface 94 faces the lower chamber 34 and is supported by the valve seat 80 and the intermediate seat member 86 in an elastically deformed state. The disc spring 87 has a generally annular plate shape, and a plurality of through-holes 96 are formed at an intermediate portion thereof. The outer peripheral edge of the groove 9
It is fixed in a state of contact with the bottom of the zero.

The hydraulic pressure of the intermediate liquid passage 46 acts on the upper surface 92 of the leaf valve 82, and the hydraulic pressure of the lower chamber 34 acts on the lower surface 94. The liquid pressure in the lower chamber 34 is controlled by the liquid passage 91 and the through hole 96.
And acts on the lower surface 94. Lower chamber 3 acting on lower surface 94
When the hydraulic pressure of No. 4 becomes higher than the hydraulic pressure of the intermediate liquid passage 46 acting on the upper surface 92 by more than the valve opening pressure (more than the hydraulic pressure difference required to bend the outer peripheral side portion of the leaf valve 82), the inner peripheral side The edge is pressed against the seat member 86, the outer peripheral side is bent upward, and the hard valve 40 is opened. The hydraulic pressure of the intermediate liquid passage 46 acting on the upper surface 92 is higher than the hydraulic pressure of the lower chamber 34 acting on the lower surface 94 by the valve opening pressure (according to the hydraulic pressure difference required to deflect the inner peripheral side of the leaf valve 82). Force and disc spring 8
7) or higher, the leaf valve 82
With the outer peripheral edge pressed against the valve seat 80, the inner peripheral side is bent downward against the urging force of the disc spring 87, and the hard valve 40 is opened.

Therefore, by providing the disc spring 87, the valve opening pressure of the hard valve 40 when the inner peripheral side is bent is hardly changed while the valve opening pressure when the outer peripheral side of the leaf valve 82 is bent is hardly changed. The pressure can be increased. Further, the damping coefficient when the inner peripheral side portion is bent is increased, and the damping force is also increased. It is possible to change the damping characteristic when the inner peripheral part bends while keeping the damping characteristic when the outer peripheral part bends substantially constant, and substantially change the shape when the outer peripheral part bends Instead, it is possible to change the shape when the inner peripheral side portion bends. Also, if the biasing force is changed by changing the installation state (for example, the inclination angle) of the disc spring 87, or if the elastic coefficient has a different magnitude (the biasing force has a different magnitude), The magnitude of the valve opening pressure and the damping coefficient when the peripheral side portion is bent can be changed.

The soft valve 42 also includes a valve seat 100, a leaf valve 102, a positioning member 104, an upper chamber side seat member 106, a disc spring 107 and the like, as shown in FIG. The outer peripheral edge of the formed annular groove 110 is used as the valve seat 100. Soft valve 4
In 2, the ratio of the outer diameter to the inner diameter of the leaf valve 102 is made larger than that of the leaf valve 82, and the radial width of the groove 110 is made larger. As a result, the leaf valve 102 is
The soft valve 42 is made easier to bend, and the soft valve 42 is made easier to open than the hard valve 40. Similarly, in the soft valve 42, the leaf valve 102 is
Can be changed without substantially changing the shape when the inner peripheral side portion bends.

The electric motor 60 is controlled by a control device 120. By controlling the electric motor, the flow passage area of the hard valve bypass passage 54 is controlled, and the damping force generated in the shock absorber is controlled.

In the shock absorber configured as described above, the force acting on the shock absorber is small, and the hydraulic fluid does not flow before the soft valve 42 is opened, but the force acting on the shock absorber increases. When the soft valve 42 is opened, the soft valve 4
2. The working fluid flows through the intermediate fluid passage 46 and the hard valve bypass passage 54. The force acting is even greater,
When the hard valve 40 is opened, a part of the working fluid flows through the soft valve 42, the intermediate liquid passage 46, and the hard valve 40. If the flow area of the hard valve bypass passage 54 is controlled, the ratio between the amount of hydraulic fluid flowing through the hard valve 40 and the amount of hydraulic fluid flowing through the hard valve bypass passage 54 can be controlled, and the ratio is generated in the shock absorber. The magnitude of the damping force can be controlled.

When the distance between the vehicle body-side member 16 and the wheel-side member 12 becomes small and a downward force acts on the piston 28 (a force in a direction to contract the piston rod 14 acts), the lower chamber 34 The hydraulic pressure becomes higher than the hydraulic pressure in the upper chamber 36. When the hydraulic pressure difference between the hydraulic pressure in the intermediate liquid passage 46 and the hydraulic pressure in the upper chamber 36 becomes larger than the opening pressure of the soft valve 42, the outer peripheral side of the leaf valve 102 in the soft valve 42 is bent upward. The hydraulic pressure in the lower chamber 34 is
If the hydraulic pressure of the hard valve 40 is higher than the hydraulic pressure of the hard valve 40, the outer peripheral side of the leaf valve 82 in the hard valve 40 is bent upward. When the distance between the vehicle body-side member 16 and the wheel-side member 12 increases, and an upward force acts on the piston 28 (a force in a direction to extend the piston rod 14), the hydraulic pressure of the upper chamber 34 decreases. It becomes higher than the hydraulic pressure of the lower chamber 36. If the hydraulic pressure difference between the hydraulic pressure in the upper chamber 36 and the hydraulic pressure in the intermediate liquid passage 46 becomes larger than the opening pressure of the soft valve 42, the leaf valve 102
Is bent against the urging force of the disc spring 107. If the fluid pressure in the intermediate fluid passage 46 becomes higher than the fluid pressure in the lower chamber 34 by the opening pressure of the hard valve 40, the hard valve 40
, The inner peripheral side portion of the leaf valve 82 is bent against the urging force of the disc spring 87.

As shown in FIG. 5, in both the hard valve 40 and the soft valve 42, by providing a disc spring, the bending shape during expansion is maintained while the shape of bending during contraction is kept substantially the same. The shape can be changed. Further, the valve opening pressure and the damping coefficient during extension are increased while these are maintained at substantially the same size during contraction, and the damping force when the relative movement speed of the piston rod 14 to the cylinder body 10 is the same is reduced. Be enlarged. Valve opening pressure ratio during extension and contraction,
The damping force ratio will be changed. In both the hard valve 40 and the soft valve 42, the damping force generated during extension is made larger than the damping force during contraction. Therefore, the damping force generated during extension in the entire shock absorber is increased. Therefore, the steering stability of the vehicle can be improved. Further, there is an advantage that the damping characteristic can be changed without increasing the size of the piston 28.

The hard valve and the soft valve are not limited to those in the above-described embodiment, but may be those described below. Hereinafter, the hard valve will be described, but the same can be applied to the soft valve. The hard valve is a hard valve 1 shown in FIGS.
50. The shock absorber provided with the hard valve 150 is a shock absorber according to an embodiment common to claims 1, 3, 7 to 9. The hard valve 150 includes a valve seat 152 provided on the piston 28,
It includes an intermediate support member 154, a positioning member 156, a leaf valve 158, and an intermediate sheet member 160 that supports the leaf valve 158 from the intermediate liquid passage 46 side.
The intermediate support member 154 includes a plurality of lower support members 164 that support the leaf valve 158 from below and an upper support member 166 that supports the leaf valve 158 from above, and the lower support member 164 is formed at an intermediate portion of the piston 28. Provided in the vicinity of the liquid passage 91 of the formed annular groove 90,
The upper support member 166 has an annular shape, and is provided so as to face the plurality of lower support members 164. The upper support member 166 is formed integrally with the intermediate sheet member 160, and a plurality of liquid passages 168 are formed between the intermediate sheet member 160 and the upper support member 166.

The leaf valve 158 is supported by the valve seat 152 and the intermediate seat member 160 at the outer peripheral edge and the inner peripheral edge in an elastically deformed state.
At the intermediate position, the lower support member 164 and the upper support member 166 support it. The leaf valve 158 is
The outer peripheral leaf valve 170, which is an outer peripheral portion of the portion supported by the intermediate support member 154, and the inner peripheral leaf valve 172, which is an inner peripheral portion, are separated. The outer peripheral leaf valve 170 and the inner peripheral leaf valve 172 can be bent independently by the intermediate support member 154.
When either one of the inner leaf valve 172 and the inner peripheral leaf valve 172 bends, the other portion is hardly affected.

When a force for contracting the piston rod 14 acts, the hydraulic pressure in the lower chamber 34 increases
6 higher than the hydraulic pressure. The liquid pressure in the lower chamber 34 is
1, acting on the lower surface of the leaf valve 158 through the groove 90,
The hydraulic pressure in the intermediate liquid passage 46 acts on the upper surface. When the hydraulic pressure of the lower chamber 34 becomes higher than the hydraulic pressure of the intermediate liquid passage 46 by a valve opening pressure or more, the outer peripheral side of the outer peripheral leaf valve 170 is bent upward with the upper support member 166 as a fulcrum. When a force for extending the piston rod 14 acts, the hydraulic pressure in the intermediate liquid passage 46 becomes higher than the hydraulic pressure in the lower chamber 34. The liquid pressure in the intermediate liquid passage 46 acts on the upper surface of the inner peripheral leaf valve 172 of the leaf valve 158 via the liquid passage 168,
The hydraulic pressure in the lower chamber 34 acts on the lower surface. When the fluid pressure in the intermediate fluid passage 46 becomes higher than the fluid pressure in the lower chamber 34 by more than the valve opening pressure, the inner peripheral side portion of the inner peripheral side leaf valve 172 becomes lower supporting member 164.
About the fulcrum.

Here, if the inner diameter of the inner leaf valve 172 is changed without changing the outer diameter of the outer leaf valve 170 (the same as changing the inner diameter of the leaf valve 158), the outer leaf valve 170 is changed. Can be changed without changing the bent shape of the inner peripheral side leaf valve 172. It is possible to change the damping characteristic of the damping force generated during elongation with little change in the damping characteristic of the damping force generated during contraction. If the inner diameter of the inner peripheral leaf valve 172 is increased (if the radial length of the inner peripheral leaf valve 172 is reduced),
As shown by the solid line in FIG. 8, the valve opening pressure during extension is increased, and the damping coefficient is increased. The valve opening pressure ratio and the damping force ratio are changed during extension and contraction. Others
Even if the inner diameter of the inner peripheral side leaf valve 172 is reduced or the outer diameter of the outer peripheral side leaf valve 170 is increased or decreased, the shape of one of the bendings of the other is hardly changed. The shape can be changed, and the attenuation characteristics can be changed. According to the shock absorber in the present embodiment, as will be described later, it is possible to prevent the piston 28 from becoming larger in the axial direction than when the valve includes a plurality of leaf valves stacked in the axial direction.

The shapes of both the outer peripheral leaf valve 170 and the inner peripheral leaf valve 172 may be changed.
When both are changed, the damping characteristics can be relatively changed, and the valve opening pressure ratio and the damping force ratio can be changed during extension and contraction. If the radial position of the leaf valve 158 of the lower support member 164 and the upper support member 166 is changed, the fulcrum of the deflection of the outer peripheral leaf valve 170 and the inner peripheral leaf valve 172 is changed, and the outer diameter and the inner diameter are changed. Can be obtained in the same manner as when both are changed.

As shown in FIG. 9, a hard valve is provided with two leaf valves 1 arranged side by side in the radial direction.
Hard valve 180 including 76, 178 can be provided. In the present embodiment, the outer peripheral side leaf valve 17
6 and the inner peripheral side leaf valve 178 can be flexed completely independently. If one flexes, it has little effect on the other. Therefore, by changing the outer diameter of the outer peripheral side leaf valve 176 and the inner diameter of the inner peripheral side leaf valve 178 independently, the shapes of the bending of the outer peripheral side and the inner peripheral side leaf valves 176 and 178 can be changed independently. The damping characteristics can be changed independently during contraction and during extension. In this embodiment, the outer and inner leaf valves 176 and 178 may be made of different materials. If any one of the materials is changed, the flexibility is changed, so that the elastic modulus can be changed. In this shock absorber, as shown in the figure, the intermediate sheet member 182 is provided separately from the member on which the upper support member 166 is formed. In this way, the degree of freedom in designing the hard valve 180 can be increased. For example, the size of the positioning member 156 and the inner peripheral side leaf valve 178 can be designed irrespective of the shape of the member provided with the upper support member 166 and the liquid passage 168. This aspect is also one embodiment of the invention described in claim 2.

Further, as shown in FIG. 10, the hard valve may be a hard valve 190 in which the intermediate support member includes the lower support member and does not include the upper support member.
Since the upper support member is not provided, the liquid passage 168 which is necessary in the above embodiment is not required. As described above, when the upper support member is not provided, the leaf valve 158 is not necessarily separated into the inner peripheral side and the outer peripheral side. During the contraction of the piston rod 14, the inner peripheral edge of the leaf valve 158 is
The outer peripheral side portion is bent by being pressed against the outer peripheral portion 60. In this case, the outer peripheral end of the intermediate sheet member 160 becomes a fulcrum. During the extension of the piston rod 14, the inner peripheral side portion of the leaf valve 158 is bent about the lower support member 164 as a fulcrum.

In this state, if the inner diameter of the leaf valve 158 is changed, the shape of the bend during extension can be changed without largely changing the shape of the bend during contraction. During contraction, the middle sheet member 160 serves as a fulcrum, so that even if the inner diameter is changed, the shape of the bending does not change so much. By changing the shape of the intermediate sheet member 160 (the position of the end on the outer peripheral side), the shape of the bend during contraction can be changed with almost no change in the shape of the bend during extension. As described above, during the contraction, the leaf valve 1
58, the outer peripheral end of the intermediate seat member 160 serves as a fulcrum, so that if the fulcrum moves to the outer peripheral side, the outer peripheral side of the leaf valve 158 will be less likely to bend; Easy to pick up. However, since the lower support member 164 serves as a fulcrum during extension, the shape of the flexure during extension is substantially the same. Conversely, if the position of the lower support member 164 in the radial direction is moved, the shape of the flexure during elongation can be changed with almost no change in the shape of the flexure during contraction. This is because the inner end of the lower support member 164 becomes a fulcrum during extension. As described above, by changing the shape of one of the intermediate sheet member 160 and the lower support member 164, the shape of flexure can be changed independently during extension and contraction, and the damping characteristics can be changed independently. Can be changed to If both are changed, the valve opening pressure ratio and the damping force ratio can also be changed. In this case, this aspect is an embodiment of the invention which is common to claims 1, 7 to 9.

Further, the hard valve can be a hard valve 200 shown in FIG. Hard valve 2
The shock absorbers containing 00
9 and an embodiment common to the first, second, seventh to ninth aspects. The hard valve 200 includes two plate-like members 20.
2, 204, a valve seat 206, a positioning member 210, an intermediate seat member 212, and the like. Plate member 202
Is supported by the valve seat 206 and the intermediate seat member 212, and the plate-like member 204 is supported by being sandwiched between the lower support portion 213 and the intermediate seat member 212 at the inner peripheral portion thereof. The lower support portion 213 is an inner peripheral edge of the groove 90 provided in the piston 28. The piston 28 also serves as a lower support member, and the intermediate sheet member 212
Will also serve as the upper support member. Plate member 204
Is arranged in a state where its outer peripheral side is overlapped with the inner peripheral edge of the plate-like member 202, and a plurality of cutouts 214 shown in FIG. 12 are formed in the overlapped portion. In the present embodiment, since the thickness of the plate member 202 is larger than that of the positioning member 210, the plate member 204 is supported in an elastically deformed state. Therefore, even when the shock absorber is not in operation,
4 applies an upward urging force to the plate-like member 202.

During the contraction of the piston rod 14, the plate member 202 is bent upward at the outer peripheral side while the inner peripheral edge is pressed against the intermediate sheet member 212. In this case, the plate member 204 is not bent.
During the extension of the piston rod 14, as shown in FIG.
6, the inner peripheral side portion is bent downward against the urging force of the plate-like member 204. The bending of the plate-like member 202 is suppressed by the plate-like member 204, so that the bending becomes difficult, the valve opening pressure increases, and the damping coefficient increases. Further, the hydraulic fluid is supplied to the plate member 202 and the intermediate sheet member 21.
2, the notch 21 provided in the plate-like member 204.
It will flow through 4.

As described above, since the hard valve 200 is opened and closed by the deformation of the plate member 202, the plate member 202 can be a leaf valve. Since the bending is suppressed, the plate member 204 can be considered as a bending suppressing member. The flexure suppressing member 204 can change the flexure shape of the leaf valve 202 during extension without changing the flexure shape of the leaf valve 202 during contraction of the piston rod 14, thereby changing the damping characteristic during extension. You can do it. Also, the deflection suppressing member 20
By changing the width L of the notch 214 of No. 4, the flexibility of the leaf valve 202 can be changed. Width L
Is smaller than when the leaf valve 202 is large, the width L can be reduced to a size corresponding to the inner peripheral end of the leaf valve 202 in FIG. , It is most difficult to bend. Similarly, even if the outer diameter of the deflection suppressing member 204 is changed, the ease of bending of the leaf valve 202 can be changed. Further, as described above, during extension, the hydraulic fluid flows through the notch 214. Therefore, if the width L of the notch 214 is increased, the flow rate of the hydraulic fluid can be increased, and the damping characteristics can be changed. it can.

In the present embodiment, the deflection suppressing member 204 is provided in a state of being elastically deformed. However, it is not essential that the bending suppression member 204 is provided in a state of being elastically deformed. When the thickness of the positioning member 210 and the leaf valve 202 are made substantially the same and the deflection suppressing member 204 is supported in a state where it is not elastically deformed, the valve opening pressure at the time of extension becomes small.

Although the plate-like member 204 is regarded as a deflection suppressing member, it can be regarded as a leaf valve. The plate-like member 204 does not bend during contraction, but bends during extension. Further, the working fluid flows through the notch 214 provided in the plate member 204,
The reason for this is that the shape of the flexure 04 affects the formation of the flow path. As described above, by changing the shape of the leaf valve 204 (the shape and the outer diameter of the notch 214), the damping characteristic during extension can be changed. It can be considered as an embodiment of the shock absorber described in 2.

The hard valve may be a hard valve 230 having the structure shown in FIG. The shock absorber including the hard valve 230 has the following features.
This is an embodiment common to 2, 7 to 9. Hard valve 2
Reference numeral 30 includes leaf valves 232 and 234, a valve seat 236, a positioning portion 240, and the like. Leaf valve 23
2 is easier to bend than the leaf valve 234, and these two leaf valves 232 and 234 have the inner peripheral edge of the leaf valve 232 overlapped below the outer peripheral edge of the leaf valve 234. Arranged in state. The positioning portion 240 is provided at an outer peripheral edge of the groove 90 of the piston 28, and has a plurality of notches 244 formed at an inner peripheral edge thereof. Leaf valve 232
Are positioned in a state where the outer peripheral surface is in contact with the inner peripheral surface of the positioning section 240. Since the notch 244 is provided in the positioning portion 240, even when the outer peripheral side portion of the leaf valve 232 is slightly bent, a sufficient flow rate of the working fluid can be allowed. The leaf valve 234 has a lower support portion 213 and a spacer 246 at an inner peripheral edge.
And supported by.

As shown in FIG. 15, the piston rod 14
During the contraction of the leaf valve 232, the outer peripheral side portion is bent upward while the inner peripheral side edge portion is pressed against the outer peripheral side edge portion of the leaf valve 234. Leaf valve 234
The outer peripheral side portion is bent upward while the inner peripheral side edge portion is pressed against the spacer 246. Leaf valve 234
Is bent by the differential pressure acting force corresponding to the hydraulic pressure difference acting on itself and the pressing force by the leaf valve 232. The opening amount of the hard valve 230 corresponds to the sum of the bending amount of the leaf valve 232 and the bending amount of the leaf valve 234. During the extension of the piston rod 14, the leaf valve 232 is pressed against the outer peripheral edge against the valve seat 236, and the inner peripheral side is bent downward.
The outer peripheral side portion is bent downward while the inner peripheral side portion is pressed against the lower support portion 213. The working fluid in the intermediate fluid passage 46 is
It flows from between the leaf valve 232 and the leaf valve 234. The opening amount of the hard valve 230 corresponds to a difference obtained by subtracting the bending amount of the leaf valve 234 from the bending amount of the leaf valve 232. As described above, since the leaf valve 234 is harder to bend than the leaf valve 232, there is a difference in the amount of bending between the leaves 232 and 234, and the flow of the hydraulic fluid is allowed between the leaves. It is. As described above, during the contraction, the valve opening pressure becomes larger and the damping coefficient becomes larger than during the extension. If both of the leaf valves 232 and 234 are bent in the same direction, the flow of the hydraulic fluid is not allowed unless the amount of bending is increased, so that the valve opening pressure is increased accordingly.

In this state, if the outer diameter of the spacer 246 is changed, the amount of deflection when the leaf valve 234 bends upward can be changed with little change in the amount of deflection when the leaf valve 234 bends downward. As a result, it is possible to change the amount of deflection during contraction without substantially changing the amount of deflection during extension. If the outer diameter of the spacer 246 is increased, the amount of deflection can be reduced, and if the outer diameter is reduced, the amount of deflection can be increased. Conversely, if the shape of the lower support portion 213 is changed, the amount of deflection when the leaf valve 234 bends downward can be changed, and the amount of deflection during extension can be changed without changing the amount of deflection during contraction. can do. Thus, the lower support member 213 and the spacer 246
By changing any one of the above shapes, the shape of the bending can be changed independently during elongation and during contraction. Also,
The damping characteristic can be changed independently, and the valve opening pressure ratio and the damping force ratio during extension and contraction can be changed.

The hard valve may be a hard valve 250 shown in FIG. Hard valve 25
Claims 1, 2, 7 to 9
FIG. Hard valve 250 is 2
Leaf valves 252, 254, positioning member 25
6,258 and the like. 2 leaf valves 2
Numerals 52 and 254 have a small difference in inner diameter and a large difference in outer diameter, and the leaf valve 254 is entirely overlapped with a part of the leaf valve 252. The leaf valve 252 located on the lower chamber 34 side includes a positioning member 256.
The leaf valve 254 positioned on the intermediate liquid passage 46 side is positioned by the positioning member 258.
52 also functions as an intermediate sheet member. The spacer 260 is an intermediate seat member of the leaf valve 254.

During the contraction of the piston rod 14, FIG.
As shown in FIG. 7, the leaf valves 252 and 254 are both bent, but during extension, the leaf valve 254 is hardly bent, and only the leaf valve 252 is bent. Here, if the outer diameter of the leaf valve 254 is changed, the bending shape when the two leaf valves 252 and 254 are bent becomes 1
The bending shape when the leaf valves 252 are bent can be changed with almost no change. If the outer diameter of the leaf valve 254 is reduced, the two leaf valves 25
When both 2254 are bent, the bending becomes easy, but the influence on the case where one leaf valve 252 is bent is small. Therefore, the bending shape during contraction can be changed with almost no change in the bending shape during extension.
In addition, if the thickness of the leaf valve 254 is increased, it is difficult to bend when the two leaf valves 252 and 254 are bent. Can be changed.

When the thickness of the leaf valve 254 is considerably increased, the leaf valve 25
Only the outer peripheral side portion 2 can be bent with the outer peripheral edge of the leaf valve 254 as a fulcrum. In this case, one leaf valve 2 is used during both contraction and extension.
52 will bend.

The leaf valve 254 may be a leaf valve 272 including a hydraulic pressure transmitting portion 268 and a plurality of through holes 270 shown in FIG. Through hole 270,
By providing the hydraulic pressure transmitting section 268, the hydraulic pressure of the intermediate liquid passage 46 can be transmitted to the upper surface 276 of the leaf valve 252 (see FIG. 17) satisfactorily. If the hydraulic pressure acting on the upper surface 276 is higher than the hydraulic pressure of the lower chamber 34 by more than the valve opening pressure, the leaf valve 254 does not flex and only the leaf valve 252 flexes well.

The hard valve may be a hard valve 280 shown in FIG. Hard valve 28
Claims 1, 2, 7 to 9
FIG. Hard valve 280 is 2
It includes leaf valves 282 and 284, an inner peripheral positioning member 286, an outer peripheral positioning member 288, and an intermediate seat member 290. 2 leaf valves 2
82 and 284 have the same outer diameter and different inner diameters, and a part of the leaf valve 284 includes a leaf valve 282.
Will overlap. The leaf valve 284 is positioned by the inner peripheral positioning member 286, and the leaf valve 282 is positioned by the outer peripheral positioning portion 288. A plurality of notches 292 are formed on the inner peripheral side of the outer peripheral side positioning portion 288, and the outer peripheral side positioning portion 288 and the outer peripheral surface of the leaf valve 282 are positioned by contact.

During contraction of the piston rod 14, FIG.
As shown in the figure, the leaf valve 282 is hardly bent,
While the leaf valve 284 is flexed, during extension the leaf valves 282 and 284 are flexed together. During contraction, leaf valve 284 is flexed with little effect from leaf valve 282. Here, if the inner diameter of the leaf valve 282 is changed, it is possible to change the bent shape during expansion without changing the bent shape during contraction. Increasing the inner diameter of the leaf valve 282 makes it easier to bend, while reducing the inner diameter makes it harder to bend. Further, even if the thickness of the leaf valve 282 is changed, the shape of the bending can be changed. Note that the leaf valve 282
May have a through hole and a hydraulic pressure transmitting portion as shown in FIG. In this case, the surface on which the hydraulic pressure transmitting portion is formed is the surface on the leaf valve 284 side.

The hard valve may be a hard valve 300 shown in FIGS. The hard valve 300 includes two leaf valves 302 and 304. The leaf valve 302 has a circular outer shape, and the leaf valve 304 has a generally rectangular shape. The leaf valve 304 is provided so as to be superposed on a part of the leaf valve 302. During the contraction of the piston rod 14, when the hydraulic pressure difference between the hydraulic pressure in the lower chamber 34 and the hydraulic pressure in the intermediate liquid passage 46 is small, only the outer peripheral side of the leaf valve 302 is supported by the outer peripheral edge of the leaf valve 304 as a fulcrum. When the valve is bent and the hydraulic pressure difference increases, both the leaf valves 302 and 304 are bent. During the extension of the piston rod 14, the inner peripheral side portions of the leaf valves 302 and 304 are both bent downward, and a large damping force is generated. When the thickness of the rectangular leaf valve 304 is changed, the fulcrum when the leaf valve 302 is bent does not change.
Although the ease of bending of the leaf valve 302 does not change, the degree of bending when both the leaf valve 302 and the leaf valve 304 bend changes. If the leaf valve 304 is thickened, it becomes difficult to bend and the valve opening pressure during extension increases. As described above, if the thickness of the leaf valve 304 is changed, it is possible to change the bent shape during extension without changing the bent shape during contraction. Also, leaf valve 3
By changing the outer diameter of 04, it is possible to change the valve opening pressure ratio and the damping force ratio during extension and contraction.

As shown in FIGS. 23 and 24, the hard valve can be a hard valve 330 including three leaf valves. The shock absorber including the hard valve 330 is an embodiment common to claims 1, 2, 7 to 9. The hard valve 330 has three leaf valves 3
32, 334, 336, a positioning member 340, an intermediate sheet member 341 and the like. Hard valve 33
At 0, three leaf valves 332, 334, 3
36 are stacked in the axial direction. The leaf valve 332 located closest to the lower chamber 34 has a small-diameter axial through hole 34.
2 are formed along the circumference of substantially the same radius, and the leaf valve 336 located closest to the upper chamber 36 side.
Is thin and easy to bend, and the leaf valve 334 located in the middle is formed with a plurality of large-diameter through holes 344. Two leaf valves 332, 334
Are arranged in a state where the small-diameter through hole 342 and the large-diameter through hole 344 are located in the same phase, that is, in a state where they are communicated with each other. The hydraulic fluid in the lower chamber 34 is supplied to the small-diameter through hole 3.
42, and transmitted to the leaf valve 336 through the large-diameter through hole 344. An orifice is formed by the small-diameter through hole 342, and the hydraulic pressure is transmitted well by the large-diameter through hole 344. These through holes 342 and 344 form a pressure guiding path.

As shown in FIG. 25, during contraction, the lower chamber 3
The fluid pressure of No. 4 acts on the lower surface of the leaf valve 336 via the pressure guiding path, and the fluid pressure of the intermediate fluid passage 46 acts on the upper surface of the leaf valve 336. If these hydraulic pressure differences are greater than the force required to flex the leaf valve 336, the inner peripheral edge of the leaf valve 336 is
1 and the outer peripheral side portion is bent upward. When the hydraulic pressure difference between the lower chamber 34 and the intermediate liquid passage 46 increases,
Since the hydraulic fluid cannot flow at a sufficient flow rate due to the orifice 342, the hydraulic pressure of the lower chamber 34 acts on the lower surface of the leaf valve 332. Three leaf valves 332, 3
The differential pressure acting force corresponding to the hydraulic pressure difference generated between
If the force required to flex the three leaf valves 332, 334, 336 is greater than the three leaf valves 33
2, 334, 336 are flexed together.

During extension, the leaf valve 33
The lower chamber 3 acting on the lower surface of the leaf valve 332 has a hydraulic pressure corresponding to the hydraulic pressure of the intermediate liquid passage 46 acting on the upper surface of the lower valve 3.
When the hydraulic pressure acting force corresponding to the hydraulic pressure of No. 4 is larger than the force required to bend the three leaf valves 332, 334, 336, the leaf valves 332, 334, 336 are moved to the outer edge. Is pressed against the valve seat 346, and the inner peripheral side portion is bent downward. All three leaf valves 332,
Since the 334 and 336 are bent, a large damping force can be generated.

In this state, the large-diameter through-hole 344 formed in the leaf valve 334 located at the middle position allows the hydraulic pressure in the lower chamber 34 to be transmitted to the leaf valve 336 in a satisfactory range. If the bending rigidity is changed to the extent that the bending rigidity is changed, the bending shape when the three leaf valves 332, 334, and 336 bend is changed almost without changing the bending shape when only the leaf valve 336 is bent. Can be. Also, the leaf valves 332, 33
Even if the thickness of the leaf valve 3 is changed, the shape of the three leaf valves 3
32, 334, 336 can be changed in the shape when it bends.

Further, a hard valve 347 shown in FIG.
It can also be. In the hard valve 347,
The inner diameter of the through hole formed in the leaf valve 332 is increased to form a through hole 348. Even if the pressure difference between the fluid pressure in the lower chamber 34 and the fluid pressure in the intermediate fluid passage 46 becomes large, the hydraulic fluid can flow at a sufficient flow rate through the through hole 348, so that the leaf valves 332 and 334 flex. I can't be beaten. Thus, even if the shape of the pressure guiding path is changed, the shape during contraction can be changed without changing the shape during expansion.

The leaf valve 334 located in the middle
If the through-hole is not formed, the leaf valves 334 and 336 will bend together during contraction, and the bent shape during contraction can be changed almost without changing the bent shape during expansion. Thus, depending on the shape of the through hole, the presence or absence of the through hole, etc., during extension and contraction,
The shape of the deflection can be changed independently, and the valve opening pressure ratio and the damping force ratio can be changed during extension and contraction.

The hard valve may be a hard valve 350 shown in FIG. Hard valve 35
0 includes three leaf valves 352, 354, and 356 as in the embodiment shown in FIG. 23, but the leaf valve 354 located in the middle has an outer diameter of a small diameter formed in the leaf valve 352. It is small enough not to block the through hole 358. As described above, since the through holes 358 are provided along the circumference having substantially the same radius,
The outer diameter of the leaf valve 354 is smaller than the radius. In the present embodiment, the outer peripheral edge of the annular groove 90 formed in the piston 28 is the valve seat 362, but the valve seat 362 is protruded from the inner peripheral edge toward the intermediate liquid passage. . The outer peripheral edge of the leaf valve 352 supported by the valve seat 362 is bent upward and pressed against the outer peripheral edge of the leaf valve 356,
These are adhered. Since the outer diameter of the leaf valve 354 is smaller than the outer diameter of the leaf valves 352 and 356, it is possible to prevent the hydraulic fluid from flowing between the leaf valves 352 and 356 when the shock absorber is not operated. In the present embodiment, if the thickness of the leaf valve 354 is changed, the shape of the deflection when the three leaf valves 352, 354, and 356 are bent without changing the shape of the deflection when the leaf valve 356 is bent. Can be changed.

The hard valve may be a hard valve 400 shown in FIG. The shock absorber including the hard valve 400 is an embodiment common to claims 1, 4, 7, and 9. The hard valve 400 includes one leaf valve 402, a positioning member 404, an intermediate seat member 406, a valve seat 408, and the like. When the leaf valve 402 is elastically deformed, And the valve seat 408.
The valve seat 408 has a shape curved inwardly as shown in the drawing. Therefore, when the inner peripheral side portion of the leaf valve 402 bends, the fulcrum thereof is moved along the valve seat 408, as shown in FIG. On the other hand, when the outer peripheral side portion is bent, the inner peripheral side edge portion is pressed against the intermediate side sheet member 406, so that the fulcrum is not moved. As described above, in the present embodiment, while keeping the bending shape during contraction substantially the same,
Since the bending shape during the extension can be changed, and the fulcrum is moved to the inner peripheral side as the fiber is bent, FIG.
As shown in (2), the damping coefficient increases as the material flexes. In this case, the valve opening pressure does not increase. It is not indispensable to change the shape of the valve seat 408 into a curved shape, and any shape may be used as long as it can be moved as the supporting position on the outer peripheral side of the leaf valve 402 is bent. Further, if the shape of the intermediate seat member 406 is similarly changed, the fulcrum when the outer peripheral side portion of the leaf valve 402 bends can be changed, and the bent shape can be changed.

The hard valve may be a hard valve 430 shown in FIG. Hard valve 43
Claims 1, 2, 6 to 9
FIG. The hard valve 430 includes a leaf valve 432 that is flexed when the piston rod is contracted and extended, a leaf valve 434 that is not flexed when extended and flexed when contracted, an intervening member 440 that includes an outer spacer 436 and an inner spacer 438. , Positioning member 44
2, including a valve seat 444, an intermediate seat member 446, and the like. These are assembled with the intervening member 440 disposed between the leaf valves 432 and 434.
The leaf valve 432 is supported on the outer peripheral side of the positioning member 442 by the valve seat 444 and the inner peripheral side spacer 438, and the leaf valve 434 is supported by the inner peripheral side spacer 438 and the intermediate seat member 446 on the inner peripheral side. It is fixed in a sandwiched state. Therefore, the leaf valve 43
4 is fixed in a state where it is bent by an amount corresponding to the difference in thickness between the inner peripheral side spacer 438 and the outer peripheral side spacer 436, that is, in a state where the outer peripheral portion of the leaf valve 434 is pressed against the pedestal 450. Will be. The inner peripheral side spacer 438 has both a function as a support member on the intermediate passage side of the leaf valve 432 and a function as a lower chamber side support member of the leaf valve 434.

As shown in FIG. 32, the outer peripheral side spacer 436 includes a pedestal 450 as a plurality of spacer portions and an annular positioning portion 452.
50 is provided on the positioning portion 452 so as to protrude radially inward with a space between the positioning portions 452.
The area between 0 is the flow path 454. Outer side spacer 436
Are mounted with the outer peripheral surface of the leaf valve 434 fitted to the inner peripheral surface of the positioning portion 452,
Can be accurately positioned with respect to the leaf valve. The outer spacer 436 may be considered as an outer interposed member, and the inner spacer 438 may be considered as an inner interposed member.

The shape of the outer peripheral side spacer 436, that is,
By changing the thickness of the pedestal 450 or changing the flow path area of the flow path 454, the shape of the bending can be changed. What is necessary is just to replace the outer peripheral side spacer 436 with one having a shape suitable for the purpose. If the thickness of the pedestal 450 is changed without changing the flow path area, the shape of the flexure during contraction can be changed without changing the shape of the flexure during extension. If the thickness of the pedestal 450 is changed, the set load of the leaf valve 434 changes, so that the ease with which the outer peripheral side portion of the leaf valve 432 bends changes. As a result, the leaf valves 432, 434
The valve opening pressure when both the outer peripheral side portions are bent can be changed. On the other hand, when the inner peripheral side portion of the leaf valve 432 bends, the ease of bending does not change, and the shape of the bending does not change.

Conversely, if the flow path area of the flow path 454 is changed without changing the thickness of the pedestal 450, the shape of the bend at the time of elongation is changed without changing the shape of the bend at the time of contraction. be able to. If the flow path area is changed, the flow resistance of the hydraulic fluid between the leaf valves 432 and 434 changes, so that the damping characteristic when the inner peripheral side portion of the leaf valve 432 is bent changes, and The shape changes. However, the shape when the outer peripheral side portions of the leaf valves 432 and 434 are both bent does not change.

As shown in FIG. 33, when the piston rod contracts, the hydraulic pressure in the lower chamber 34 becomes higher than the hydraulic pressure in the upper chamber 36. If the pressure difference between the liquid pressure in the lower chamber 34 and the liquid pressure in the intermediate liquid passage 46 becomes larger than the liquid pressure difference (valve opening pressure) required for bending both the leaf valves 432 and 434, both the leaf valves 432 and 434 Of the hard valve 43 is bent upward about the intermediate side seat member 446 as a fulcrum.
0 is opened. During extension, the hydraulic pressure in the upper chamber 36 is reduced.
Larger than the hydraulic pressure of The working fluid in the intermediate fluid passage 46 is supplied between the leaf valves 432 and 434 via the flow passage 454. An intermediate liquid passage 46 is provided on the upper surface of the leaf valve 432.
Of the lower chamber 34 acts on the lower surface.
When these hydraulic pressure differences exceed the valve opening pressure required for the leaf valve 432 to bend, the inner peripheral side portion of the leaf valve 432 is bent downward with the valve seat 444 as a fulcrum, and the hard valve 430 is opened. .

In the above embodiment, the intervening member 440 is formed by the inner spacer 438 and the outer spacer 43.
However, the inner peripheral side spacer 438 is not indispensable. Also, it is not essential that the thickness of the inner peripheral side spacer 438 be smaller than the thickness of the pedestal 450,
It may be the same thickness. Further, the inner peripheral side spacer 438 and the outer peripheral side spacer 436 can be integrally formed. If formed integrally, the positioning portion 452
Is not essential. Further, the shape of the outer peripheral side spacer 436 is not limited to the above-described embodiment, and may be other shapes. Two leaf valves 432, 4
It is only necessary to have a spacer portion for providing a gap between the upper and lower portions 34 and a pressure guiding portion for guiding the hydraulic fluid in the upper chamber 36 to the gap. The annular member may be provided with a through hole extending in the radial direction.

Further, the hard valve may be a hard valve 458 shown in FIG. Hard valve 45
8 is a leaf valve 4 in the hard valve 430.
32 and 434 are turned upside down. Further, the intermediate side seat member 460 is connected to the leaf valves 432, 4
34, a shape extending further from the outer peripheral edge to the outer peripheral side. A plurality of liquid passages 462 are formed in an intermediate portion of the intermediate sheet member 460, and the working fluid in the intermediate liquid passage 46 is supplied to the upper surface of the leaf valve 432 via the liquid passage 462. The above-described leaf valve 4 of the intermediate seat member 460
The portions on the outer peripheral side from the outer peripheral edges of 32 and 434 project downward, and the lower surface of the annular projection 463 is engaged with the outer peripheral edge 464 of the groove 90 of the piston 28 in a liquid-tight manner. The inner peripheral side of the protrusion 463 and the leaf valve 432,
A gap is formed between the first and second leaf valves 432 and 434 through the outer peripheral spacer 436.
It is said. The leaf valve 434 has an inner peripheral side portion,
The leaf valve 4 is supported while being sandwiched from above and below.
32 is an inner peripheral side spacer 438 and an intermediate side sheet member 46.
0 and supported by

During contraction, the liquid pressure in the lower chamber 34 becomes higher than the liquid pressure in the intermediate liquid passage 46. The hydraulic fluid in the lower chamber 34 is
Liquid passage 91, groove 90, liquid passage 466, outer peripheral side spacer 4
36, two leaf valves 434, 4
32, the inner peripheral portion of the leaf valve 432 is bent upward with the lower surface 467 of the intermediate seat member 460 as a fulcrum. During extension, the fluid pressure in the intermediate fluid passage 46 becomes higher than the fluid pressure in the lower chamber 34. The working fluid in the intermediate fluid passage 46 is supplied to the upper surface of the leaf valve 432 via the fluid passage 462, and the outer peripheral portions of the leaf valves 432 and 434 are both bent downward. As described above, in the present embodiment, the valve opening pressure during extension is larger than the valve opening pressure during contraction.

Further, the leaf valve 434 and the outer peripheral side spacer 436 can be considered as a bending suppressing member for suppressing the bending of the outer peripheral side portion of the leaf valve 432. In this case, the shock absorber according to the above embodiment can be considered as one embodiment of the invention described in claim 5. FIG. 35 shows a hard valve 468 as an example. In the hard valve 468, the leaf valve 434 is a dish-shaped leaf valve 470, and the outer peripheral side spacer 436 is not provided. Plate type leaf valve 4
A plurality of flow paths 474 are formed in the inclined portion 472 of 70, and the working fluid in the intermediate liquid passage 46 is supplied to the inside of the dish-shaped leaf valve 470, that is, the upper surface of the leaf valve 432 via the flow path 474. By forming the leaf valve 470 into a dish shape, a gap can be created between the two leaf valves even without the outer peripheral side spacer 436. By providing the dish-shaped leaf valve 470, the outer peripheral side portion of the leaf valve 432 is hardly bent, and the shape of the outer peripheral side portion is changed without changing the shape of the inner peripheral side portion of the leaf valve 432. be able to.

Further, in each of the above embodiments, the valve included in the shock absorber according to one embodiment of the present invention is applied to both the hard valve and the soft valve, but may be applied to only one of them. . It is not essential to apply the same type of valve to the hard valve and the soft valve, and different types of valves may be applied. Further, the positioning member in each of the above embodiments may be provided with a notch. If the notch is provided, the flow of the working fluid at a sufficient flow rate can be allowed at an early stage of the start of bending. Further, the structure of the shock absorber is not limited to that in the above-described embodiment. Even when the hard valve is provided in parallel with the soft valve and the liquid passage provided in series with the soft valve, one of the hard valve and the soft valve may be used. The present invention can be applied to shock absorbers having various structures such as a structure provided with only a shock absorber. Also, the present invention can be applied to a shock absorber in which the piston rod is provided on the wheel side instead of the vehicle body side. That is, the structure of the piston in each of the above embodiments can be made the same, and the piston rod can be extended downward to provide a shock absorber provided on the wheel side. In this shock absorber, the hydraulic pressure in the lower chamber becomes higher than the hydraulic pressure in the upper chamber during extension, and the hydraulic pressure in the upper chamber becomes higher than the hydraulic pressure in the lower chamber during contraction. As described above, some embodiments of the present invention have been described in detail. However, these are merely examples, and the present invention is described in the section [Problems to be Solved by the Invention, Means to Solve, Action and Effect]. The present invention can be carried out in various modified and improved aspects based on the knowledge of those skilled in the art, including the aspects described above.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view around a piston of a shock absorber according to an embodiment of the present invention.

FIG. 2 is a sectional view of the entire shock absorber.

FIG. 3 is an external view of the entire shock absorber.

FIG. 4 is a sectional view of a hard valve included in the shock absorber.

FIG. 5 is a diagram showing a damping characteristic of a damping force generated in the hard valve.

FIG. 6 is a sectional view of a hard valve included in a shock absorber according to another embodiment of the present invention.

FIG. 7 is a view of the piston provided with the hard valve as viewed in the direction of arrow A.

FIG. 8 is a diagram showing a damping characteristic of a damping force generated in the hard valve.

FIG. 9 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 10 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 11 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 12 is a partial plan view of a plate member included in the hard valve.

FIG. 13 is an operation diagram of the hard valve.

FIG. 14 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 15 is an operation diagram of the hard valve.

FIG. 16 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 17 is an operation diagram of the hard valve.

FIG. 18 is a partial sectional view of another leaf valve included in the hard valve.

FIG. 19 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 20 is an operation diagram of the hard valve.

FIG. 21 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 22 is a plan view of the hard valve.

FIG. 23 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 24 is a plan view of a leaf valve included in the hard valve.

FIG. 25 is an operation diagram of the hard valve.

FIG. 26 is an operation diagram of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 27 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 28 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 29 is an operation diagram of the hard valve.

FIG. 30 is a view showing a deflection curve of a leaf valve included in the hard valve.

FIG. 31 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 32 is a perspective view of an outer peripheral side spacer included in the hard valve.

FIG. 33 is an operation diagram of the hard valve.

FIG. 34 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

FIG. 35 is a sectional view of a hard valve included in a shock absorber according to yet another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Cylinder main body 14 Piston rod 28 Piston 30 Damping force control device 40,150,180.190,200,230,25
0,280,300,330,347,350,40
0, 430, 458, 468 Hard valve 42 Soft valve 82, 102, 158, 176, 178, 202, 23
2,234,252,254,272,282,28
4,302,304,332,334,336,35
2,354,356,402,432,434,470
Leaf valve 87, 107 Disc spring 154 Intermediate support member 160 Intermediate seat member 164 Lower support member 166 Upper support member 213 Upper support member 246 Spacer 408 Valve seat 436 Outer peripheral spacer 438 Inner peripheral spacer 440 Interposed member 450 Base 452 Positioning member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazunari Uemura 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Toshiyuki Kobayashi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation

Claims (9)

[Claims] 1. A cylinder body, a piston for partitioning the interior of the cylinder body into two chambers, and increasing and decreasing the volume of the two chambers with a relative movement with respect to the cylinder body, a piston rod fixed thereto, and the piston rod A valve that permits the flow of hydraulic fluid from the higher pressure chamber of the higher pressure chamber to the lower pressure chamber of the lower pressure chamber in both the extended and retracted states. An absorber, wherein the valve is a leaf valve having flexibility, and without substantially changing the shape of deflection of the leaf valve in one of the state of extension and contraction of the piston rod, And a bending shape changing means capable of changing a bending shape in the other state. 2. The method according to claim 1, wherein the valve includes a plurality of leaf valves, and at least one of the plurality of leaf valves has a shape that can be changed independently of other leaf valves. The shock absorber according to claim 1, wherein the flexible shape can be changed independently. 3. The leaf valve has a generally annular plate shape, and the valve has an intermediate support member that supports the annular plate leaf valve at an intermediate position between an inner peripheral edge and an outer peripheral edge. The shape of a portion of the leaf valve on either one of the outer peripheral side and the inner peripheral side of the intermediate support member can be changed, and the shape can be changed, and the bending shape change can be performed. The shock absorber according to claim 1 or 2, which constitutes the means. 4. The leaf valve is generally in the form of an annular plate, and the valve is provided with one of the two chambers at an outer peripheral edge thereof. An outer peripheral valve seat supported from the chamber side, and an inner peripheral valve seat supported at the inner peripheral edge from the other chamber side, and one of the outer peripheral valve seat and the inner peripheral valve seat is included. The shock absorber according to any one of claims 1 to 3, wherein the shape of the shock absorber is changeable, and the shape of the shock absorber is changeable. 5. The leaf valve has a generally annular plate shape, wherein an inner peripheral portion bends in one of a state in which the piston rod is extending and contracting, and an outer peripheral side in the other state. Wherein the bending shape changing means includes a bending suppressing member that suppresses bending of one of the inner peripheral portion and the outer peripheral portion of the leaf valve. The shock absorber according to any one of claims 1 to 4. 6. A one-sided deflection including one or more leaf valves, wherein the valve bends when the hydraulic pressure in the first chamber of the two chambers is higher than the hydraulic pressure in the second chamber, and does not bend when the hydraulic pressure in the first chamber is low. A leaf valve group, a two-leaf leaf valve group including one or more leaf valves that bends when the hydraulic pressure of the first chamber is higher or lower than the hydraulic pressure of the second chamber, An intervening member having a flow path for supplying the hydraulic fluid in the second chamber is provided between the two groups, and a shape of the intervening member is changeable. The shock absorber according to any one of claims 1 to 5, wherein said bending shape changing means comprises a shape that can be changed. 7. A cylinder body, a piston for partitioning the interior of the cylinder body into two chambers, and increasing and decreasing the volume of the two chambers with a relative movement with respect to the cylinder body, a piston rod fixed thereto, and the piston rod And a valve that permits the flow of hydraulic fluid from the higher pressure chamber of the two chambers to the lower pressure chamber of the lower pressure in both the extended and retracted states. An absorber, wherein the valve has a damping characteristic change that can change the damping characteristic in the other state while maintaining the damping characteristic in one of the states of extending and contracting the piston rod substantially constant. A shock absorber comprising means. 8. A cylinder body, a piston for partitioning the interior of the cylinder body into two chambers, and increasing or decreasing the volume of the two chambers with relative movement with respect to the cylinder body, a piston rod fixed thereto, and the piston rod A valve that permits the flow of hydraulic fluid from the higher pressure chamber of the higher pressure chamber to the lower pressure chamber of the lower pressure chamber in both the extended and retracted states. An absorber, wherein the valve allows a flow of the hydraulic fluid when a differential pressure between the high-pressure chamber and the low-pressure chamber is equal to or higher than a valve-opening pressure, and during the extension of the piston rod. Shock absorber comprising valve opening pressure ratio changing means capable of changing a valve opening pressure ratio which is a ratio between a valve opening pressure during extension and a valve opening pressure during contraction during contraction. Server. 9. A piston for partitioning the interior of the cylinder body into two chambers and increasing or decreasing the volume of the two chambers in accordance with relative movement with respect to the cylinder body, a piston rod fixed thereto, and the piston rod A valve that permits the flow of hydraulic fluid from the higher pressure chamber of the higher pressure chamber to the lower pressure chamber of the lower pressure chamber in both the extended and retracted states. An absorber, wherein the valve has an extension damping force generated during extension of the piston rod and a contraction damping force generated during contraction when the relative movement speed of the piston rod to the cylinder body is the same. And a damping force ratio changing means capable of changing a damping force ratio which is a ratio of the shock absorber.