JPS5818545B2 - Vehicle hydraulic shock absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic shock absorber for a vehicle in which the damping force characteristics on the compression side can be freely changed.

More specifically, an orifice plate with a plurality of orifices with different diameters is provided at the bottom of the buffer, and this orifice plate is rotated by a simple external operation to select the orifice facing the passage. In addition to making it possible to change the damping force characteristics by selecting oil flow control on the valve side, the operating member of the orifice plate is exposed to the U-shaped bracket provided at the bottom of the shock absorber to protect the operating part. The present invention relates to a hydraulic shock absorber for a vehicle.

Various types of hydraulic shock absorbers that combine a hydraulic damping force generator and an elastic member such as a coil spring have been proposed and put into practical use as shock absorbers for vehicles.

A type of such a shock absorber having an inner cylinder and an outer cylinder, a hydraulic chamber provided in the inner cylinder, and a reservoir chamber provided between the inner cylinder and the outer cylinder is constructed as follows, for example.

That is, it is equipped with a piston that slides in a hydraulic chamber, which is equipped with an orifice, a check pulp, an oil passage, etc. In the hydraulic chamber divided by the piston, damping force is obtained by controlling the flow rate of the orifice during the tension stroke, and during the compression stroke. Now open the check valve to ensure oil flow.

A bottom valve is provided at the bottom of the hydraulic chamber to communicate the reservoir chamber and the hydraulic chamber, and this valve has an orifice that acts during the compression stroke and a return oil passage that opens the check pulp during the tension stroke and allows it to flow between the compartments. Be prepared.

In the tension stroke, the orifice on the piston side acts mainly to obtain a damping force, and in the compression stroke, the orifice on the bottom valve side acts mainly to obtain a damping force.

Incidentally, the damping force characteristics of such a hydraulic shock absorber are determined by the settings of each orifice, and the damping force characteristics are fixedly determined depending on the orifice.

Therefore, when changing the damping force characteristics, the orifice must be changed.

However, the required damping force characteristics of shock absorbers for storage vehicles vary depending on loading conditions, driving conditions, user preferences, etc.
Therefore, there is no choice but to prepare shock absorbers according to each condition and install them selectively for each vehicle, or to share shock absorbers with damping force characteristics similar to the greatest common denominator.In reality, the latter is the most common choice. occupy

To further discuss the damping force characteristics of shock absorbers, the preferred damping force characteristics of shock absorbers vary depending on the user's preferences, loading conditions, and driving conditions. For example, when driving on rough terrain, a shock absorber for general city driving or one with damping characteristics is quick and easy. The ride quality is unfavorable due to the stroke.

-In order to prevent this, increasing the damping force on the compression side is preferable from the above point of view and stability during high-speed driving.However, when driving on ordinary paved roads or at normal speeds, Because the damping force is large, the piston speed is relatively slow, and the shock load is also small, making it difficult for the initial shock absorbing effect to be effective, giving the vehicle a rugged feel, and the shocks caused by small obstacles on the road are directly transmitted to the occupants. Decreases riding comfort.

As mentioned above, the damping force characteristics of a shock absorber vary depending on the usage conditions of the vehicle in which it is used, so it is difficult to practically satisfy all of them with one type of shock absorber. There is no choice but to share a buffer or prepare and select a plurality of buffers; the former cannot solve the above problem, and the latter increases the cost of the buffer, and increases the trouble and complexity of assembly.

In any of the above cases, the set damping force characteristics do not change, and it is not possible to obtain damping force characteristics according to the conditions for the seven types of vehicles.

Therefore, in order to solve the above problem, it is possible to make the orifice on the bottom side variable and change the orifice according to the vehicle conditions, driving conditions, etc. to make the damping force characteristics variable, but this would lead to a complicated structure, There are problems such as the operating mechanism is difficult to operate, the operating section is exposed to the outside and can be used for mischief, and furthermore, the operating section needs to be protected from the outside.

1. In view of the above-mentioned problems with conventional hydraulic shock absorbers for vehicles, particularly in obtaining damping force during the compression stroke, the present inventors have developed the present invention to effectively solve these problems.

The object of the present invention is to provide an orifice plate □ equipped with a plurality of orifices with different hole diameters in the bottom part of the buffer, to selectively expose the orifice plate to the passage, and to pivot the orifice plate out of the bottom of the buffer. The orifice of the orifice plate is rotated through the operating shaft extending in the direction to selectively expose the orifice to the passage, and the end of the operating shaft is inserted into the downwardly open U-shaped bracket provided outside the bottom. To provide a hydraulic shock absorber for a vehicle in which the orifice plate is rotated outside the bottom of the shock absorber in a bracket.

Therefore, it is an object of the present invention to create a system in which the damping force on the compression side can be customized (selected and changed) depending on the loading conditions of the vehicle, driving conditions, user preferences, etc., even though it is a single type of shock absorber. To provide a hydraulic shock absorber for a vehicle that is highly versatile and capable of obtaining optimal damping force characteristics and buffer characteristics for various conditions.

In particular, the present invention has a plurality of orifices with different hole diameters on the plate, and rotates the plate to selectively match any one of the orifices with the oil passage of the bottom valve. It is easy to adjust the damping force, and the selection movement is reliable and easy.The operating shaft, which is the operating member of the plate, extends outside the bottom of the shock absorber and faces inside the U-shaped bracket, making it easy to operate. The present invention provides a hydraulic shock absorber for vehicles with variable damping force designed to protect operating parts.

Another object of the present invention is to fabricate orifices by providing the plurality of orifices radially on a disc-shaped plate, and having at least two of the plurality of orifices facing the oil passage of the bottom pulp provided at a distance. To provide a hydraulic shock absorber for a vehicle that absorbs the above error by controlling the flow rate of at least two sets of orifices, makes the damping force adjustable, and has no variation.

Furthermore, the object of the present invention is to provide a retaining part of at least two stages on the outer periphery of the extending operating part of the operating shaft, and to provide a moderating part on the bracket side that elastically engages with the retaining part. To provide a hydraulic shock absorber for a vehicle with an adjustable damping force, which ensures the above-mentioned adjustment, maintenance operation, and maintenance at the relevant position.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Further objects and advantages of the invention will now become apparent.

FIG. 1 is a longitudinal sectional view showing the whole hydraulic shock absorber according to the present invention, and FIG. 2 is an enlarged sectional view of the bottom portion.

The shock absorber 1 consists of an inner and outer double cylinder body 2 and 3, and a hydraulic chamber A is provided in the inner cylinder 2, and a reservoir chamber B is provided between the inner cylinder and the outer cylinder 2 and 3.

A piston 4 is slidably fitted in a hydraulic chamber A in the inner cylinder 2, and a piston rod 5 fixed to the piston 4 is attached to the inner cylinder 2.
A rod guide 6, an oil seal 7, and a lid body 8 are inserted vertically through the inside.
A mounting member 9 to the vehicle body is fixed to the upper end of the rod 6, and a spring receiver 10 provided at this portion and a receiver provided on the outer periphery of the intermediate portion of the outer cylinder 3; A return spring 12 made of a coil spring is provided between the
has been reduced.

The piston 4 is provided with an orifice 13 running vertically, a return oil passage 14, a slide valve 15 that opens during the tension stroke, a check valve 16 that opens during the compression stroke, and the like.

The bottoms of the inner and outer cylinders 2 and 3 are closed with a bottom piece 20.

The bottom piece 20 has a cup shape. This is fitted and fixed to the lower end of the outer cylinder 3, and a bottom valve body 21 is provided on the bottom piece 20, and a stepped part 22 provided on the upper outer periphery of this is fitted and fixed to the lower end of the inner cylinder 2, It positions the lower ends of both cylinders 2 and 3 and functions as a spacer.

A plurality of oil passages 23 are vertically installed in the valve body 21 in a radial manner, and radial passages 24 are provided below the oil passages 23. communicates with the reservoir chamber B via grooves 25 provided in the inner diameter of the bottom piece 20.

Pulp body 2 corresponding to the upper opening of oil passage 23...
1, a groove 26 is provided at the upper end of each oil passage 23 to fit an appropriate one or all of them, and this groove 26 is provided toward the outside in the radial direction, There are at least two grooves 26, for example approximately 18 grooves.
The grooves 26 are spaced apart by 0°, and the grooves 26 communicate with appropriate or all of the oil passages 23, respectively.

A through hole 27 is provided in the center of the bottom piece 20, and a guide cylinder portion 27 is provided outside the bottom of the hole 27 to surround it.
8 is integrally provided, and the φ of the pulp body 21 is
A through hole 29 is provided in the center portion concentrically with the through hole 27, and an operating shaft 30 is fitted vertically into the through hole 27. 20
The cylindrical portion 28 is extended downward by an appropriate length.

An orifice plate 31 is placed on the valve body 21, and the orifice plate 31 has a large outer diameter so as to close the groove 26.
The diameter is set to be slightly smaller than the diameter of the stepped portion 22.

A regulating hole 32 is provided in the center of the orifice plate 31 and is configured to fit and engage with a regulating portion 33 of an operating shaft 30 having a cross section that matches the opening, so as to rotate together with the operating shaft 30.

A plate-shaped check valve 34 having a diameter sufficiently smaller than the orifice plate 31 is provided on the lower surface of the orifice plate 31.

A valve spring 35 bent into a V shape is provided on the orifice plate 31, and the upper end of the valve spring 35 is connected to the operating shaft 3.
The clip 36 is attached to the upper end of the valve 0, and the orifice plate 31 and check valve 34 are constantly pressed downward.

A plurality of orifices a... are provided radially in the portion near the inner diameter of the orifice plate 31 that is closed by the check valve 34, and these orifices a... It is a square hole and has a fixed orifice.

A plurality of movable orifices b... are provided in a portion near the outer diameter of the orifice plate 31, and these orifices b...
... is 4 in the illustrated column and % bl to b2 z
The diameter of the orifice b is gradually increased from b3 to tb4, and the orifice b is disposed above the groove 26.

In the illustrated example, as shown in FIGS. 5 and 6, orifices b□ and b2 are always engaged with one groove 26A, and orifices b3 and b4 are selectively connected to the other groove 26B.
It takes.

That is, in the illustrated example, a combination of orifices b1 e b2 and b3 and a combination of orifices bl j b2 and b4 can be selected as shown in FIGS. 5 and 6.

This is the combination of groove 26 and orifice b.
and b3 a b2 and b4, or the number of orifices b may be increased and the combination may be three or more (,
In either case, the number of orifices is small (in both cases, two or more orifices are in the concave groove 26).
Be careful.

This has the effect of absorbing variations in damping force characteristics due to errors in molding small-diameter orifices by combining two orifices.

Therefore, even if the orifice is formed into a minute size, the above-mentioned variations can be prevented from occurring, and individual performance can be made uniform.

A bracket 40 is fitted and fixed to the outer periphery of the cylindrical portion 28 extending outward from the bottom of the bottom piece 20.

The bracket 40 forms a U-shape that opens downward, and is fitted and fixed to the outer periphery of the cylindrical portion 28 through a vertical hole 44 provided in a piece 43 that connects the left and right hanging pieces 41 and 42 at the upper part. At the bottom of the pieces 41 and 42, mounting holes 45 and screw holes 46 for the east side of the vehicle are provided concentrically, and the bottom of the shock absorber is attached to the axle extension.

The lower end portion 37 of the operating shaft 30 extends downward from the top piece 43 surrounded by the left and right pieces 41 and 42, and a restraining portion 38 is provided at the extending end. 50 is configured to rotate integrally with the operating shaft 30.

Recesses 51 and 52 are provided on the outer periphery of the moderation member 50, and the recesses 51 and 52 are shaped like <1' as shown in FIG.
Two sets are provided, separated by so degrees.

A moderation spring 60 is mounted on the inner wall of the upper end of the left and right pieces 41, 42 of the bracket 40 on the outside of the moderation member 50.
will be established.

As is clear from FIG. 8, the moderation spring 60 consists of left and right pieces 6L and 62 that are engaged with the left and right pieces 41 and 42, and a bulging engagement portion 63 and 63 that are provided in the middle of these pieces 61 and 62, respectively.
The projections 63 and 63 selectively engage with the recesses 51 and 52 of the moderation member 50 for positioning.

'In the illustrated row, the movable orifices are a combination of two sets, so there are two recesses 51 and 52, but if the number increases, a corresponding number shall be provided to match the combination angle of the movable orifices. .

In the illustrated row, the moderation spring 60 has a connecting piece 64 at the top, a through hole 65 is formed in this part, and this connecting piece 64 is stacked on the bracket top piece 43 and connected to the operating shaft 30 extending from the top piece 43. Fits rotatably and clips 3 on the lower end of the shaft.
The moderation member 50 regulated in the axial direction at 9 restricts the connection piece 64 from being pulled out and removed, and the moderation spring 60 is attached to a predetermined position.

Next, to explain its operation, the downward movement of the piston 4 causes the chamber A to
The oil on the lower surface of the orifice plate 31 is compressed, and the orifices that match the grooves 26A and 26B of the orifice plate 31 described above, in FIG.
B, reservoir chamber B via oil passage 23, passage 24, and groove 25
This oil flows into the orifice b 1 "p'"
Damping force is generated under cross-sectional area control by t)"2 and b3.

When the piston is at high speed, the oil pressure on the lower surface of the piston 4 is also high (in this case, the check valve 34 is closed to the central orifice a.
It is pushed down by the hydraulic pressure acting on the orifice a...
・opens, and oil flows through the above orifice B and this orifice a・
It is controlled by the sum of the cross-sectional areas of...

Therefore, the orifice b on the movable side operates in the low piston degree range.

When changing the damping force characteristics on the compression side described above, insert a tool etc. into the upper part of the bracket 40, rotate the moderation member 50 from outside the bottom of the bottom piece 20 via the tool etc.
For example, as in No. 8-, the engagement between the projection 63 of the moderation spring 60 and the recess 51 is released, and the recess 5'2 and the projection 63 are engaged.

In this case, the protrusion 63 is elastically bent, climbs over the mountain, engages with the recess 52, and is maintained in this position.

As a result, as shown in FIG. 6, the orifice plate 31 rotates when the operation shaft 300 rotates, and the orifice t)
2 and b4 face the concave grooves 26A and 26B, and are subject to cross-sectional area control by the orifice diameter, resulting in a damping force different from that described above.

In this manner, the orifice plate is rotated by operating the bottom portion surrounded by the bracket 40, the orifice is selected, and the damping force characteristics are adjusted in two steps.

As shown above (of course, it is possible to adjust three or more stages, and in the row shown, the low-speed and high-speed orifices are provided in two stages, but it is also possible to provide multiple sets of single-stage orifices and select them.
Of course, it is good to change it.

FIG. 10 shows a modified example of the operation mechanism of the orifice plate 31, and the moderation spring 60 has the same structure as above, but the moderation member is changed.

That is, the central portion 1 coupled to the operating shaft 30 of the moderation member 150
53 is formed into a disk shape, and arms 154, 154 are integrally extended at symmetrical positions on the outer periphery of the disk.
54 extends outwardly from the space between the pieces 41,42 of the bracket 40.

Engagement recesses 151 and 152 are provided on the outer periphery of the central portion 153.
...is provided for protection.

According to this, the moderating member 150 can be rotated via the arms 154, 154, and the orifice plate 31 can be rotated by hand without using any tools.

11 to 13 show a second embodiment of the invention.

The basic structure of the shock absorber is the same as above, only the operating mechanism has been changed, so the same parts are given the same reference numerals.

A moderating member 250 is coupled to the lower end of the operating shaft 30 of the orifice plate 31, and an arm 254254 is integrally extended at a symmetrical position on the outer periphery of the central portion 253 of this member 250, and is connected between the pieces 41 and 42 of the bracket 400. Extends outward from the space.

Part 1, buttock: 2, 3 has an engaging recess 251 on the outer periphery, and one piece 41 of the bracket 40 has a threaded hole 241 extending across it, and inserts an adjustment screw 260 into this from the outside with a washer 266. A blind hole 262 with an opening 261 at the tip is formed in the screw 260, this hole 262 is closed with a head 263, and a coil spring 264 is compressed in the blind hole 262 to close the hole. The steel ball 265 facing the opening 261 of the moderation member 262 is pressed, and the steel ball 265 is engaged with either the recess 251 or 252 of the moderation member 250.

As a result, the feeling of moderation is improved by the elastic locking action between the ball and the coil spring, and the elastic locking becomes more reliable.

In the illustration, it is provided on one side, but it may be provided on both sides, and the elastic locking force can be adjusted by advancing and retracting the screw 260.

As is clear from the above, according to the present invention, the loading conditions of the vehicle,
Even though it is a single type of shock absorber, the damping force on the compression side can be customized and changed depending on driving conditions, user preferences, etc., making it highly versatile and providing the optimal damping force for various conditions. Characteristics, buffers can be custom made.

In particular, according to the present invention, the orifice facing the oil passage is changed by operating the orifice plate with the operating shaft extending outside the bottom of the shock absorber, and the operating portion of the operating shaft faces the base of the U-shaped bracket. In addition to being easy to use, it can be protected from the outside, ensuring operability and preventing erroneous or mischievous operations.In addition, the operation part does not protrude into the outer periphery of the shock absorber, making it easier to use in terms of appearance and layout. This is preferable and also advantageous in terms of space utilization.

In addition, since the orifices are provided in the plate in the present invention, manufacturing is easy, and the number of orifices is small (two orifices are placed facing the oil path, so minute errors in machining the orifices can be absorbed by the combination of the two orifices mentioned above). , a variable damping force type shock absorber having uniform damping force characteristics can be easily obtained.

Further, according to the present invention, since the operating section is provided within the bracket base as described above, the moderation spring can be held in this section and easily engaged with the moderation member provided on the operating section, and the variable The position holding and moderation mechanism can be easily configured.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal sectional view of a hydraulic shock absorber, FIG. 2 is an enlarged sectional view of the same essential parts, and FIG. 3 is a longitudinal sectional view of the bottom part and bracket. Fig. 4 is a side view of the same, Fig. 5 is a plan view of the orifice plate, Fig. 6 is a plan view of the same changed state, Fig. 7 is a longitudinal sectional view, Fig. 8 is a plan view of the moderation spring, Figure 9 is the same side view, Figure 10
The figure is a bottom view of the modified embodiment, FIG. 11 is a vertical cross-sectional view including the buffer of the second embodiment, FIG. 12 is an enlarged view of the same main part, and FIG.
The figure is a partially broken bottom view of the same. In the drawings, 1 is a shock absorber, 2 is an inner cylinder, 3 is an outer cylinder, 4 is a piston, 5 is a rond, 9 is a mounting part, 20°21 is a bottom part, 23 is an oil passage, 30 is an operating shaft, and 31 is a orifice spray), bl ~ b4 is orifice, 40 is bracket, 5
0 is a moderation member, 60 is a moderation spring, A is a hydraulic path,
B is a reservoir chamber.

Claims (1)

[Claims] 1 Equipped with an inner and outer cylinder, a piston provided at the tip of the iron with an attachment part to the vehicle body side etc. at the base end is slidably fitted into the hydraulic chamber in the inner cylinder, and the piston between the inner and outer cylinders is fitted. In a hydraulic shock absorber for a vehicle in which a reservoir chamber and a hydraulic chamber are communicated through a bottom valve section provided at the bottom, an oil passage is provided vertically in the bottom valve part, and a plurality of orifices with different diameters are installed in this oil passage. At least two orifice blenides formed
orifices are provided so as to face the oil passage, and the orifice plate is connected to an operating shaft provided in the axial direction in the bottom valve portion, and the end of the operating shaft is provided at the bottom with the end thereof extending outward from the bottom. A moderation member having at least two pairs of concave mooring portions spaced apart by 180' on the outer periphery is fitted to the extended end of the operating shaft for mounting on a downward-facing vehicle, etc. A hydraulic shock absorber for a vehicle, characterized in that a moderation elastic member is provided at a bracket base, and the moderation elastic member is provided with a bulging engagement protrusion that engages with any pair of concave engagement portions of the moderation member when the operating shaft is rotated. vessel.