JPH01255734A - Damping force regulating type shock absorber - Google Patents

Abstract

PURPOSE:To enable nearly independent damping force to be set over the whole speed range by making up a piston valve mechanism of a soft valve device and a medium valve device, and enabling the passage of both devices to be opened or closed by means of a changeover valve device. CONSTITUTION:A hard valve device is constituted so that a back-face relief valve 13 for controlling hard-mode pressure side back-face damping force and a relief valve 14 for controlling the same hard-mode extension side low-speed damping force are faced to the other side-surface side of a stopper 11. In a piston nut 19, a medium valve device is incorporated. The passage by which a receiving chamber A is communicated with a receiving chamber 6 via respective valve devices in a first piston 1 and a second piston 15 is opened by a rotary valve 20. Thus, the setting of damping force can be independently carried out over the whole piston speed range.

Description

[Detailed Description of the Invention] [Industrial Application Field] Kibatsuj relates to a shock absorber with adjustable damping force,
More specifically, in addition to a soft damping force generating means and a hard damping force generating means, it is provided with one stage of damping force generating means intermediate between them, and it is possible to switch between these means by external operation. This invention relates to a shock absorber that is optimal for use in vehicle suspensions, etc.

(Prior Art) As an adjustment means for this type of damping force adjustable shock absorber, switching operation of a rotary valve device in a piston valve mechanism is used to adjust two types of shock absorbers with different characteristics. Selectively cut off the valve device and orifice passage (+, 3j! 1
A configuration that obtains a damping force of 3J and a regular jfH has been disclosed (Japanese Utility Model No. 59-93178).

That is, the damping force of the heart motor with this configuration is generated when the rotary valve device is in the operating position where all of the bows 1 on the screw 1 to rotor sides are closed, and the heart valve device assembled to the piston part causes At that time, the rebound and compression damping forces can be adjusted to the state shown by characteristic line I+ in the JSB diagram.

The damping force of the medium motor is generated when the two ports of the rotary valve device or the piston rod are opened to communicate with the L chamber side. The characteristic ff1M in the figure is achieved by a medium valve device placed in the piston nut at the lower end of the piston rod under the closure of the orifice bypass port. It is possible to adjust it to the state shown in .

Furthermore, the damping force of the soft motor can be adjusted by rotating the rotary valve device to open the bypass port in addition to the medium mode switching state, and to control the hydraulic fluid flow path by the medium valve device. By flowing a part of the hydraulic oil flow path through the bypass path that communicates between the upper and lower chambers, the medium damping force is reduced and 5 times 1'
4, L-characteristic line S. The adjustment state shown by is reached.

Therefore, the damping force of the soft moat in such a case is lower than the medium damping force over the entire range of piston speed,
Furthermore, from the viewpoint of the orifice knee 42 of the bypass passage, the larger the difference in damping force between the two motes, the better.

In addition, in this medium mode, the medium valve installation and the heart valve installation are in a configuration under parallel action, so the damping force in this medium mode is also lower than the damping force in the heart mode over the entire speed range. Become.

The damping force characteristics between each mode are as follows:
The compression side damping force, which adjusts and adapts the piston surface damping force, is also substantially the same as the expansion side N and force, and the result is as shown in FIG. 8 above.

(Problem to be solved by Part 4) In other words, according to the conventional damping force adjusting means of the 378 type, the damping force in the heart mode is controlled by the valve, so the damping force at that time is adjusted over the entire speed range. However, since the damping force in soft and medium modes only sets the orifice area of the bypass passage, the degree of freedom in adjusting the damping force in these modes is restricted. However, there may be cases where the shock absorber cannot achieve its full function.

Therefore, in view of the limitation of one degree of freedom in setting the damping force of the soft and medium motors in the conventional means, the present invention provides separate valve devices for the soft valve device and the medium valve device in addition to the bird valve device. hand,
By selectively controlling communication between these valve devices.

The objective is to develop a valve mechanism that can set damping forces that are substantially independent of each other over the entire speed range of each mote.

[Means to solve the problem] In order to achieve this purpose, 6 unreleased Ijll-
In a damping force adjustable piston valve mechanism equipped with a switching valve device inserted into a piston rod, C is a soft valve device and a medium valve disposed above and below the piston valve mechanism or heart valve device. of the passages of each of these valve apparatuses, at least the passages of the soft and medium valve apparatuses are connected to the switching valve! We propose a damping force adjustable shock absorber that can be opened and closed by a device.

[For production]

The switching valve device assembled to the screw-on rod consists of a rotary valve or a slide valve, and by operating this, at least the soft valve device 2
Alternatively, it is possible to selectively open and close each passage of each valve apparatus, such as a medium valve apparatus, which faces the passage communicating with the inside of the cylinder 2, which is divided into upper and lower parts with the piston in between.

This allows the open passage valve device to generate independent damping forces across the range of piston speeds, depending on the damping force setting function built into the valve.

(Examples) Hereinafter, the present invention will be explained based on 171 examples.

In one embodiment of the invention, 1 is a first piston for assembling a soft valve, which is attached to the tip of a piston rod 3 inserted into a cylinder 2 via a collar 4. Or, it is formed in a non-sliding type with a gap between the outer periphery and the inner periphery of the cylinder 2, and the boats 5a and 5b are opened in the axial direction, and the boats 5a and 5b on one end surface are opened. 5b faces the leaf hull pro that controls the damping force in the medium speed range in the soft moat, and the notched leaf valve 7 and the pressure side 1'' facing the boat 5a on the other end seat surface act in the low speed range on the rebound side. A soft valve device consisting of a back leaf valve 8 for controlling the surface damping force, and a leaf spring 93 for urging these from the back is assembled.

Reference numeral 11 denotes a valve stopper, which is constructed so as not to be in sliding contact with the inner periphery of the cylinder 2, and has a through hole 12 opened in the axial direction, and the first piston 1 and its assembly are held at the center of the valve stopper by the valve device. At the same time, the valve lift of the notched leaf valve 7 and the rear leaf valve 8 is controlled at the outer circumferential portion of the negative side.

On the other side of this stopper II (on the right side in the figure), there is a leaf spring gb that is the same as the leaf spring 9d, a back leaf valve 13 that controls the compression side back damping force in the hard mode, and a heart motor extension. A notched leaf valve 14 for controlling the side low-speed damping force is faced, forming a hard valve device, and the stopper I+ is arranged between the first piston L side and the second piston 15 symmetrically. The members 9a, 13 and 14 are sandwiched between the members 9a, 13 and 14, and the lift of the valves 13 and 14 is restricted at the outer periphery.

This second piston 15 has a boat 1 [ia and 16b whose outer periphery is configured in a cylindrical joint type and which is opened in the axial direction. (The valve I7 is arranged to control the damping force in the medium speed range, and the valve stopper 18, which regulates the amount of deflection of the valve 17 through the skin thickness gap, is placed against the center of the valve 17 and assembled. .

Then, each component described in -L is fastened by a piston nut 19 screwed onto the tip of the piston rod 2.

- On the other hand, a rotary valve 20 driven by an external actuator (not shown) is arranged in the hollow piston rod 2, and boats 21a and 21b of the valve 20 are arranged.
In order to assemble the collar 4 and the first piston l, through holes 22a and 22b are opened in the inner circumferential surface of the rod, on which the rod rotates, toward the chamber C formed between the collar 4 and the outer circumference of the rod. At a pivoting position of the rotary valve 20 where the boats 21a, 21b and the through holes 22a, 22b coincide, a passage communicating with the cylinder chambers A and B is opened, and at another pivoting position, the passage is closed. It is.

Further, the rotary valve 20 is connected to the boat 218°21.
In addition to b, an axial boat 29 is provided at a position orthogonal to the boat opening position, and a through hole 30a, :IO
A circumferential groove 31 is provided in the center hole wall 12 of the first piston 1 by drilling b and connecting these through holes 30a and :job, and the circumferential groove 31 faces the punched hole of the notched leaf valve 7. While opening the through hole 33, the boats 21a, 2
Another bow 1-12 in a direction parallel to 1a and 21b
a and 32b, and a corresponding rod side through hole 34a.
, :14b to another circumferential groove 5 and through hole 36.
37 to communicate with the cylinder chamber B.

A medium valve device is assembled to the piston nut 19. That is, the boat 4 opened in the axial direction
A leaf spring 43 is placed on one side of the valve base 41 having the boat 40a and the boat 40b, a rear leaf valve 44 that controls the compression side rear damping force in the medium mode, and a switch valve 44 that also controls the rebound side low speed damping force in the medium mode. A leaf valve 45 is held in the center of the cover 42 under wrist control by the valve cover 42, and a leaf valve 46 for controlling the damping force in the medium speed range of the medium motor is mounted on the seat surface of the boat 40b on the other side as a valve stopper. 4
It is assembled by applying it to its center under the deflection amount Mj according to 7.

In addition, in the configuration of the above embodiment, the first piston ll:
The main components of the soft valve device that attaches Ml (leaf hull pro, notch leaf valve 7, back leaf valve 8.
leaf spring 9a, etc.) and the heart valve device that is assembled to the second piston 15 (leaf valve 17).
, notched leaf valve 147v-plane leaf valve 13, leaf spring 91), etc.) are the valley shape of each of them, the size of the notch, the thickness of the +1v-plane leaf valve, the number of leaf valves. The damping force setting corresponding to each mode can be determined by adjusting the damping force.

According to the embodiment having such a configuration, the rotary valve 20 has a moving position determined by an externally operated actuator, and the boat 21a.

21b is aligned with the boats 22a, 22b of the piston lot 3, and the passage that connects the chamber A to the chamber B via the respective valve devices in the first piston 1 and the second piston 15 is opened.

In this state, in the low-speed operation range of the expansion side piston movement, the hydraulic oil in chamber A or the notch in the first piston 1 side assembly consisting of a soft valve device with low wave path resistance passes through the extension gap of chamber A. It passes through the leaf valve 7, passes through the boat sb, the chamber C1 through holes 22a, 22b, the boats 21a, 21b, and reaches the lot hollow passage, and from there it passes through the boat 12aj2b, the boats 34a, 14b, the circumferential groove [5] and the passage 36.37. It then flows into the chamber B, thereby controlling the damping force in the low speed range. Of course, the medium valve device at this time opens the lot hollow passage to the chamber B side through the passage core.

It is in an inactive state y6.

In the middle and high speed range of piston operation, the hydraulic oil from chamber A passes through the punched hole inside the notched leaf valve 7, passes through the boat 5a, and flows into chamber C while being controlled by 'l#' by the leaf pal flow. After that, via the route described in 1t1, the room B was reached.
2, the damping force in the medium and high speed range is controlled.

Furthermore, even if the heart valve device located in parallel with the soft valve device starts operating in the high speed range, the characteristics of the soft valve device can be set in anticipation of the operation of the heart valve device. Certain degrees of freedom are not lost.

On the other hand, the rotary valve 20 is driven by an actuator and is controlled in the medium mode in the state shown in the second drawing, in which the rotary valve 20 is rotated 90 degrees from the first shown state to the occupied position. That is, the boats 21a, 21b or the through holes 22
a, 22b out of alignment and severing the communication between them, the passage through the soft valve device in the aforementioned first piston 1 is closed, while the boat 29
Since Oa or CoOb coincide with the boat], the extension side piston moves and the hydraulic oil in the chamber A passes through the gap and enters the passage of the punched hole of the notched leaf valve 7, the circumferential groove 31,
It flows from the through holes 30a and 30b and the boat 29 to the lot hollow passage, and flows into the chamber B under the sole control of a medium valve device whose main components are leaf valves 44 and 45t and a leaf spring 43%, and the damping force of the medium moat. controlled or controlled.

The third section shows the damping force adjustment state of the heart motor obtained by further rotating the rotary valve 20 by 90'' from this medium mode control state.

That is, in this state, each ball l-21a, 2 on the valve side that communicates the chamber A and the hollow part of the rotary valve 20 is
Since 1b and boat 29 are occluded, hydraulic fluid flow through the soft and medium valve arrangements is blocked. As a result, the hydraulic oil in the fifth compartment A moves to the compartment B only under the control of the hard valve device including the leaf valves 13, 14, 17, etc., so that the damping force of the heart motor is generated depending on the settings of the valve device.

I will explain a specific example of setting the damping force in each of these valve devices. First, in the case of the rebound damping force of the heart motor described in #iii, the notch face material of the notch leaf valve I4 is adjusted to reduce the speed at low speed. The damping force is set in the range (0.1 m/s), and the damping force in the medium speed range (0.3 m/s) is set depending on the stiffness of the leaf valve 17. Also, the damping force in the high speed range (0.6 m/s or more) is set by adjusting the passage area of the boat +5a.

And the overwhelming heart damping power is 1! Face leaf valve 17
The rear damping force is adjusted and set depending on the rigidity of the boat 16a and the passage area of the boat 16a.

Therefore, in setting the damping force of this Heart Mort, both the extension side and the compression side can be set completely freely.For example, it is possible to set the damping force as shown in the seventh characteristic line H on A. be.

On the other hand, the setting of the rebound damping force of the medium mote is
A low speed range is set by the notch area of the notched leaf valve 45, and a medium speed range is set by the rigidity of the leaf valve 46. The high speed range is set by adjusting the area of the boat 40b. Note that the compression side damping force is set by adjusting the back damping force depending on the area of the boat 40a and the rigidity of the back leaf valve 44. As a result, even in the case of this medium motor, the damping force can be set over the entire speed range, so that the damping force as shown by the characteristic line in FIG. 7 can be obtained.

According to the above-described embodiment, the damping force setting in the soft mode is naturally also a circular motion. That is, the soft mode operates completely independently of the soft valve device or the medium valve device.

The damping force in the low speed range is set by the notch area of the notched leaf valve 7 of the soft valve device, the damping force in the medium speed range is set by the rigidity of the leaf valve 6, and the passage area of the boat 5a is set in the high speed range. Adjust and set. As a result, as shown by the characteristic line Sl in FIG. 7, the notch area of the notched leaf valve 7 is increased to lower the damping force in the low speed range, and conversely, the area of the boat 5a is decreased to reduce the damping force in the high speed range. By increasing the rise of the damping force, it is also possible to set a damping force that exceeds the damping force under the medium mode.

Therefore, for example, in damping force control under soft mode, it is possible to ensure a sufficiently soft riding comfort in a low speed range, and to obtain a damping force equivalent to the medium mode without a switching operation even in a high speed range.

In this manner, according to the above embodiment, it is possible to selectively switch and operate three independent valve devices by operating the rotary valve.

During this switching operation, the hard valve device is placed in the parallel position with respect to the soft or medium valve device, and as mentioned above, damping force control in soft or medium mode, especially in the high speed range, is Soft or medium valve devices must be set to take into account the effects of hard valve devices on the control.6 Therefore, such soft and medium valve device settings should be avoided, including bird valve devices. FIG. 4 shows a configuration in which each valve device is made independent.

That is, in this embodiment, members similar to the functional members in each embodiment described in L will be described with the same symbols, but in particular, in this embodiment, the first piston 1 and the second screw 1
A seal 28 that slides on the inner peripheral wall of the cylinder 2 is installed on the outer periphery of the valve stopper 11' located between the valve stopper 11' and the cylinder 15 to separate the first piston 1 side and the second piston 15 side in the loft outer peripheral area. It is configured as follows.

Further, the rotary valve 20 is connected to the boat 218°21.
In addition to b, :12a, :12b, and 29, there is an axial cut groove 29a in the boat opening position and the 60° turning direction.
At the same time as 1 subsidence, II! ! Through holes SOa and 50b are provided which form a pair with the through holes :lOa and :lOb bored in the loft inner circumferential wall where 29a rotates, and these through holes SOa
, 50b is connected to the valve stopper 11'.
provided in the wall of the center hole, and from the circumference vI451 to the passage 5.
There is no communication with the chamber E via 2.

Therefore, in the rotary valve 20 shown in No. 413, the boats 21a, 21b or the through hole 22a of the piston rod 3,
22b, respectively, the soft valve device in the first piston 1 operates in the same way as in the first illustrated embodiment described above, or when the device δ is connected to the valve stop 11' with the seal 28. The rotary valve 20 is cut off from the second piston 15 side by 9a and through holes 30a, 5
0a] In a state of misalignment with Ob and Sub, the circumferential groove 31
．． 51 is also closed, so only the soft valve device operates independently. Therefore, the soft valve device can obtain the damping force in the soft moat described above by setting its width. , and when performing medium mode operation, the state shown in the fourth figure above is applied! 5
The rotary valve 20 is rotated 60'' in the left-hand thread direction as shown in FIG.
a and] Ob, and the second piston 1
5 and the valve stopper II' and are in the cutoff state, the medium valve device 2 assembled to the piston NAND 19 functions in the same manner as in the state shown in the second figure. , the damping force at that time is controlled.

Furthermore, when performing a heart-swinging operation, the rotary valve 20 is further turned by 60'' by the actuator to occupy the position shown in the sixth figure.

As a result, the through holes 22a, zzb and the through hole 34a
.

14b is closed, while the cut groove 29a of the rotary valve 20 or the through hole: lOa, 50a and the through hole 30b
.

As a result, the hydraulic oil flows through the punched hole of the notched leaf valve 7 in the chamber A]
[K, circumferential groove 311 through hole] Oa, removed? + Kui 29a,
Through the through hole 30b and the through hole 34, the valve stopper 11'
After reaching the side chamber E, the hard valve device is operated to generate a predetermined damping force in the same manner as in the above-mentioned embodiment No. 31.4.

In each of the above embodiments, the positional relationship between the rotary valve side boat and the piston rod side passage hole for mode switching is not limited to the illustrated position, and a passage for the intended switching can be formed. As long as it is in good condition,
In addition to the illustrated rotary valve, a conventionally known mechanism such as a slide valve may be used as the valve system for switching the mote.

(9, Light effect) In this way, according to the end-of-life shock absorber,
Consists of a soft valve device and a medium valve device placed above and below the heart valve device, respectively.
Among the passages of each of these valve units, at least the passages of the soft and medium valve apparatuses are configured to be able to be opened and closed by the switching valve apparatus. It is possible to set the damping force independently over the entire range of piston speed.1 It is possible to adjust the damping force well suited to the application and adjustment intention.01
Its effects are extremely useful in practical applications.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of the main part showing the soft mode operating state in an embodiment of the device of the present invention, FIG. 2 is a longitudinal sectional side view of the main part showing the medium mode operating state, and FIG. FIG. 4 is a longitudinal sectional side view of the main part showing the state of operation, FIG. 4 is a longitudinal sectional side view of the main part showing the rough 1 to mode operating state in another embodiment of the device of the present invention, and FIG. 5 is a main part MFfrgII showing the medium mode operating state. Front view, ``6th
The figure is a vertical sectional side view of the main part showing the hard mote operating state, FIG. 7 is a damping force characteristic diagram in the operating states shown in FIGS. 1 to 3, and No. 8 IN is a damping force characteristic diagram in each operating state in the conventional device. . DESCRIPTION OF SYMBOLS 1...First piston, 2...Cylinder, 3...Piston rod, 11 and 11''...Valve struba, 15...Second piston, 19...Piston Nand, 2υ... Rotary valve. Figure 7 Figure 8

Claims (1)

[Claims] In a damping force adjustable piston valve mechanism equipped with a switching valve device inserted into a piston rod, the piston valve mechanism consists of a soft valve device and a medium valve device respectively disposed on the upper and lower sides of a hard valve device, sandwiching the hard valve device. A damping force adjustable shock absorber characterized in that, among the passages of each valve device, at least the passages of the soft and medium valve devices can be opened and closed by the switching valve device.