JPH022108Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic shock absorber, and more particularly to a hydraulic shock absorber that has a desired large damping effect when contracted.

Extensible hydraulic shock absorbers have long been in demand for use in tensioning caterpillars, for example, and recently there has also been a demand for them in new mounting forms for rear suspension units of motorcycles. There is.

Therefore, the inventor of the present application previously proposed an extendable hydraulic shock absorber as shown in FIG. and,
Since the suspension spring 1 in this hydraulic shock absorber has a repulsive force in the direction of contraction, one end is attached to the base member 2' attached to the outer periphery of one end of the outer tube 2, and the other end is attached to the rear end of the piston rod 3. The base member 4' is connected to a support member 4 attached to the base member 4, and is fixed from the lateral direction using caulking members 5, 5, respectively. Therefore, although it has become possible to achieve the intended purpose of obtaining an extensible hydraulic shock absorber by using this hydraulic shock absorber, the following problems have been found.

That is, in order to fix the suspension spring 1, which has a repulsive force in the contraction direction, in a desired position by a force from the lateral direction, each of the crimping members 5, 5 must ensure a considerably large crimping force, and this crimping pedestal members 2', 4' that receive force, and an outer tube 2 to which the pedestal members 2', 4' are attached;
The support member 4 must have a considerable thickness in order to have sufficient durability, which may significantly increase the weight of the entire hydraulic shock absorber. In order to avoid this increase in weight, if ultra-high hardness steel is used, there is a risk that the hydraulic shock absorber will become expensive and uneconomical. Further, since the suspension spring 1 is exposed to the outside, there is a disadvantage that it is not suitable for use under the requirement that the suspension spring 1 must be hidden.
Even if a cover is to be attached to cover the suspension spring 1, it is difficult to attach a so-called bellows-type cover, and attaching covers that slide into contact with each other will increase the thickness of the entire hydraulic shock absorber. There are some disadvantages that are inconvenient.

Therefore, the present invention provides a hydraulic shock absorber having a new configuration that makes it possible to obtain a desired hydraulic shock absorber equipped with a cover that hides the suspension springs without holding the suspension springs using lateral caulking force. The purpose is to provide Another object of the present invention is to provide a hydraulic shock absorber in which the repulsive force of a suspension spring can be adjusted and the spring constant can be selected.

Then, the basic configuration for achieving the above purpose is as follows.
A piston attached to the tip of a piston rod inserted from one end of the cylinder divides the inside of the cylinder into one chamber and the other, and a free piston placed inside near the other end of the cylinder allows air to flow through the cylinder. In a hydraulic shock absorber which is formed by dividing a chamber and further having a suspension spring on the outside of the cylinder, and is formed so as to provide a desired damping effect by sliding of a piston part, there is a slide cylinder on the outer periphery near the other end of the cylinder. The suspension spring has a repulsive force in the direction of extension, and one end of the suspension spring is latched to the outer periphery of one end of the cylinder from the axial direction, and the other end is attached to a spring receiver arranged on the outer periphery of the other end of the cylinder. The spring receiver is attached to the rear end of the piston rod, and is connected to the other end of the cover extending toward the other end of the cylinder, and its inner periphery coincides with the outer periphery of the slide cylinder. It is designed to make sliding contact.

Hereinafter, the present invention will be explained based on the illustrated embodiments.

As shown in FIG. 2, the hydraulic shock absorber according to the present invention includes a cylinder 10, a piston rod 20 inserted into the cylinder 10, a piston portion 30 formed at the tip of the piston rod 20, and a piston portion 30 formed at the tip of the piston rod 20. a suspension spring 40 interposed externally;
A cover 50 is attached to the piston rod 20.

The cylinder 10 has one chamber A and the other chamber B partitioned by a piston portion 30 inside, and also has a free piston 11 disposed inside near the other end. Thus, it has a partitioned air chamber C inside the other end. One chamber A and the other chamber B are filled with oil, and the air chamber C is filled with gas at an appropriate pressure.

Further, a bracket 12 is fixed to the outside of the other end of the cylinder 10. Inside one end of the cylinder 10, there is provided a bearing 13 that slides on the piston rod 20, and a support member 14 that holds the bearing 13. This support member 14 is prevented from moving by a caulking groove 15 formed in the cylinder 10, and is held in a predetermined position via a seal member 17 by a cap 16 fitted to the other end of the cylinder 10. It is established.

The piston rod 20 has a bracket 21 at its rear end and, as described above, a piston portion 30 at its tip. This piston rod 20 has a through hole 22 bored in its axial center, and a through hole 23 that allows communication between one chamber A and the other chamber B in the cylinder 10 through this through hole 22 is formed in the piston rod. 20 radially perforated holes.
Further, an adjuster 24 is rotatably interposed in a portion of the through hole 22 that faces the through hole 23, and the adjuster 24 has a diameter that selectively faces the through hole 23 when the adjuster 24 rotates. A plurality of orifices 24' having different diameters are bored. This adjuster 24 has a through hole 2 of the piston rod 20.
Adjuster rod 2 rotatably interposed within 2
The tips of 5 are connected by a spline connection or the like. The rear end of the adjuster rod 25 is connected to a rotating mechanism 26 within a bracket 21 which is secured to the rear end of the piston rod 20.

Therefore, the operation knob 26' of this rotation mechanism 26
When the adjuster rod 25 is rotated, the adjuster rod 25 rotates, and as the adjuster rod 25 rotates, the adjuster 24 rotates within the through hole 22 of the piston rod 20. A plurality of orifices 24' having different diameters are bored in this adjuster 24.
One of them is selected and faces the through hole 23 bored in the piston rod 20.
As a result, when the hydraulic shock absorber is extended, the through hole 2 of the piston rod 20 is moved from the other chamber B of the cylinder 10.
A desired damping effect can be produced when oil flows into one chamber A of the cylinder 10 through the opening 2 and the through hole 23.

The piston portion 30 is formed to provide a desired large damping effect when the hydraulic shock absorber contracts.
1 provides the desired damping effect. This leaf valve 31 is connected to a stopper 3 that is engaged with a stepped portion 20' of the piston rod 20.
The oil hole 33' is disposed so as to close an opening at one end of an oil hole 33', which is bored through a thick wall portion of the piston 33 which is in contact with the inner peripheral surface of the cylinder 10 and is in sliding contact with the inner circumferential surface of the cylinder 10. . This leaf valve 31 has a tightening tool 3 that is screwed onto the tip of the piston rod 20 via a shim 34 and a control plate 35 so that the inner peripheral end is fixed and the outer peripheral end is free.
It is fixed by 6. The leaf valve 31 has a non-return spring 37 between its outer peripheral end and the control plate 35 so that the leaf valve 31 functions as a non-return valve.

Therefore, when the hydraulic shock absorber contracts, that is, when the piston part 30 moves to the other chamber B side in the cylinder 10, the leaf valve 31 closes the adjacent oil hole 33' and the piston part 30
However, when the hydraulic shock absorber extends, the piston portion 3
0 moves to the one chamber A side of the cylinder 10, the leaf valve 31 is deflected by the oil flow passing through the oil hole 33', and at this time, the desired large damping effect is performed. .

In addition, one end is attached to the support member 14 so that the piston part 30 does not collide with the bearing 13 or the support member 14 inside one end of the cylinder 10 when the piston part 30 moves toward the one chamber A side. A coil spring 39 is disposed in one chamber A of the cylinder 10, and the coil spring 39 is fixed to a stopper 38 and has its other end engaged with a stopper 32 attached to the piston portion 30.

Further, although it is said that the desired large damping force generation action in the piston portion 30 is performed by the leaf valve 31, it is of course possible to use an appropriate orifice bored in the piston 33 instead of this. be.

The suspension spring 40 is formed to have a repulsive force in its extension direction, and one end is locked to a stopper 41 fixed to the outer periphery of one end of the cylinder 10, and the other end is fixed to the outer periphery of the other end of the cylinder 10. It is locked to a spring receiver 42 located at. The spring receiver 42 is connected to the other end of the cover 50, which will be described later, and is also connected to the cylinder 10.
It is in sliding contact with the outer periphery of a slide cylinder 43 attached to the outer periphery from the other end to the vicinity thereof.

Therefore, when the suspension spring 4 extends, the cylinder 10 moves in the direction of contraction of the hydraulic shock absorber, and when the suspension spring 40 contracts, the cylinder 10 moves in the direction of extension of the hydraulic shock absorber. Become. In either case, the spring receiver 42 is attached to the slide cylinder 4 attached to the cylinder 10.
It will slide on 3. Since this suspension spring 40 has a repulsive force in its extension direction, it slides in contact with a stopper 41 attached to one end of the cylinder 10 and the other end of the cylinder 10, and is supported by a cover 50, which will be described later. By doing so, the cylinder 10 is moved in the direction of contraction of the hydraulic shock absorber. In other words, the hydraulic shock absorber is a hydraulic shock absorber having a repulsive force in the direction of contraction thereof.

A cover 5 that connects the spring receiver 42 to the other end
0 is connected to a mounting member 51 fixed to the rear end of the piston rod 20. However, in this embodiment, the cover 50 is not fixedly attached to the mounting member 51, but is attached to the support member 51, as compared to other embodiments (FIG. 3) described later. A slidable cover 50 is provided so as to be movable in the axial direction of the cylinder 10.

Therefore, a slide member 52 is attached to one end of the cover 50, and the slide member 52 is slidably adjacent to the outer periphery of the mounting member 51. 50 is set to move. The sliding movement of the slide member 52 is as follows.
This is done by allowing oil to flow into the area adjacent to the mounting member 51 or by discharging the oil that has flowed into the area adjacent to the slide member 52.
A hole 52' is bored in the hole 52', a connector 53 is connected to the hole 52', and the connector 53 is connected to an external oil pump 54.

Although the slide member 52 connected to one end of the cover 50 is slid by using hydraulic pressure in this embodiment, it may be moved manually instead of this. The slide member 52 is connected to the slide member 51 by a screw thread.
It may also be done by screwing them together.

Furthermore, in the illustrated embodiment, the sliding movement of the slide member 52 on the outer periphery of the mounting member 51 is restricted by the mounting member 51 on the one hand, and the snap ring 55 attached to the mounting member 51 on the other hand.
It is regulated by. In order to protect the sliding surface of the mounting member 51, the mounting member 5
A telescopic dust cover 56 is attached between the slide member 1 and the slide member 52.

Therefore, when oil is supplied by operating the oil pump 54, the slide member 52 moves in the direction of extension of the hydraulic shock absorber. Since the cover 50 is connected to the slide member 52, the cover 50 also moves in the same direction, and thereby the spring receiver 42 connected to the other end of the cover 50 also slides in the same direction. As a result, the suspension spring 40 is compressed by the amount of movement of the spring receiver 42, and has a larger repulsive force. Furthermore, once the suspension spring 40 is compressed, the oil pump 54
This is restored by moving the slide member 52 in the extending direction of the hydraulic shock absorber, that is, by moving the cover 50 in the same direction. That is, by selectively operating the oil pump 54, it is possible to adjust the repulsive force of the suspension spring 40.

The cushion is designed to prevent one end of the cylinder 10 and the rear end mounting member 51 of the piston rod 20 from directly colliding with each other and damaging either or both of them when the hydraulic shock absorber is fully contracted. A material 57 is attached to the mounting member 51.

FIG. 3 shows a hydraulic shock absorber according to another embodiment of the present invention.

The feature of this embodiment is that the embodiment shown in FIG.
The cover 5 is configured to be slidable at the attached portion to allow the spring receiver 42 to slide.
0 does not allow sliding, but is different in that the spring receiver 42 itself is configured to be directly slidable.

To explain briefly, this hydraulic shock absorber includes a cylinder 10, a piston rod 20 inserted into the cylinder 10, a piston portion 30 formed at the tip of the piston rod 20, and a cylinder 10.
The basic structure, which includes a suspension spring 40 interposed on the outside of the piston rod 20 and a cover 50 attached to the piston rod 20, is the same as the embodiment shown in FIG.

Further, the cylinder 10 has one chamber A and the other chamber B partitioned by the piston portion 30;
The cylinder 10 shown in FIG. 2 has a free piston 11 and an air chamber C.
It's not at all different. And piston rod 20
It has a through hole 22 in its axis, and inside the through hole 22, an adjuster 24 and an adjuster rod 25 are rotatably provided. The piston rod 20 is not different from the piston rod 20 shown in FIG. Further, the piston portion 30 is configured to include the leaf valve 3
1 and is formed so as to be able to generate a desired large damping force when the hydraulic shock absorber contracts, and is completely different from the piston portion 30 shown in FIG.

The suspension spring 40 has one end locked to a stopper 41 fixed to the outer periphery of one end of the cylinder 10, and the other end locked to a spring receiver 42 positioned near the other end of the cylinder 10. This spring receiver 42 is attached to a slide cylinder 4 attached to the outer periphery from the other end of the cylinder 10 to the vicinity thereof.
3 so that it can slide freely.

That is, the spring receiver 42 is connected to the slide cylinder 4
The suspension spring 40 is connected to a piston member 42d that is slidably housed in a casing 42c held by a seat member 42b that is in sliding contact with the outer periphery of the suspension spring 40 through a bearing member 42a. When the cylinder 10 moves in the direction of extension or contraction of the hydraulic shock absorber, the bearing member 4
It slides on the other end of the cylinder 10 via 2a.

Further, the piston member 42d is connected to the casing 42
When pressure oil is supplied from the external oil pump 54 into c, the hydraulic shock absorber moves in the direction of contraction, compressing the suspension spring 40 that is in contact with the spring receiver 42. Conversely, the suspension spring 4 once compressed
0, when the oil pump 54 is operated to discharge pressure oil from inside the casing 42c, the piston member 4
2d is moved in the direction of extension of the hydraulic shock absorber, thereby causing the suspension spring 40 to be extended. That is, the repulsive force of the suspension spring 40 can be adjusted by moving the piston member 42d forward or backward.

The spring receiver 42 is adapted to slide on the inner periphery of the other end of the cover 50 when the piston member 42 d connected thereto slides, and the casing 42 c that accommodates the piston member 42 d slides on the inner periphery of the cover 50 .
Since it is connected to the other end of the cover 50, it is connected to the other end of the cover 50.

This cover 50 is connected to a mounting member 51 fixed to the rear end of the piston rod 20 via a plate 58. Therefore, the suspension spring 40 that is locked to the other end of the cover 50 via the spring receiver 42
has one end locked to one end of the cylinder 10, and since the suspension spring 40 has a repulsive force in its extension direction, this hydraulic shock absorber is configured to have a repulsive force in its contraction direction. As a result, the hydraulic shock absorber becomes an extendable hydraulic shock absorber.

Incidentally, the piston portion 30 is formed so as to exert a desired large damping effect when the cylinder 10 moves in the direction of contraction of the hydraulic shock absorber, as in the case of the embodiment shown in FIG. Of course.

As described above, the present invention has the following effects.

The suspension spring, which functions to contract the hydraulic shock absorber, has a repulsive force in its extension direction, and also locks both ends of the spring in its axial direction, so it can be prevented from lateral movement by using crimping force. Compared to the case of fixing, there is no need to further improve the durability of the fixing member, the fixed member, and the members to which they are attached, and there is no need to increase the weight of thick-walled members or use ultra-high hardness steel. There is an advantage that there is no need to worry about causing uneconomical problems.

The suspension spring is placed inside a cover attached to cover the cylinder, and is locked to a spring holder provided at the end of the cover, so the suspension spring is not exposed to the outside and is free from mud etc. It has the advantage that it can be used even under usage conditions where there is a risk of adhesion. Therefore, it can be used, for example, for tensioning caterpillars, and as a new mounting form for rear suspension units of motorcycles in recent years.
A desired hydraulic shock absorber can be obtained.

Since the spring receiver is in sliding contact with the outer periphery of the slide cylinder, it does not interfere with the vicinity of the other end of the cylinder on which the free piston slides, and does not damage the cylinder in this area or adversely affect the slidability of the free piston.

Since the suspension spring is separated from the outer periphery of the cylinder by the thickness of the slide cylinder and can be expanded and contracted along the outer periphery of the slide cylinder, the suspension spring does not come into contact with the outer periphery of the cylinder, and vibrations in the radial direction are also suppressed. Therefore, damage to the outer periphery of the cylinder and occurrence of abnormal noise can be prevented.

Since the inner periphery of the spring receiver at the cylinder side end of the cover is configured to be in sliding contact with the slide cylinder, when a bending action is applied to the hydraulic shock absorber, this load is borne by the piston rod and is Since there is no need to increase the diameter of the piston rod, the weight can be reduced accordingly.

In addition, if the adjuster is installed internally, it becomes possible to select a suitable damping force, and by configuring the suspension spring so that the repulsion force can be adjusted, there is an advantage that a preferable spring constant can be set. .

[Brief explanation of the drawing]

Fig. 1 is a partially cut-away front view of a conventional hydraulic shock absorber, Fig. 2 is a partially cut-away front view of a hydraulic shock absorber according to an embodiment of the present invention, and Fig. 3 is a partially cut-away front view of a conventional hydraulic shock absorber. FIG. 3 is a front view showing the embodiment similar to FIG. 2; 10...Cylinder, 20...Piston rod,
30...Piston part, 40...Suspension spring, 42...
...Spring holder, 50...Cover, A...One chamber, B...
...The other room.

Claims (1)

[Claims for Utility Model Registration] (1) The inside of the cylinder is divided into one chamber and the other chamber by the piston part attached to the tip of the piston rod inserted from one end of the cylinder, and the interior near the other end of the cylinder is divided into one chamber and the other chamber. A hydraulic shock absorber which defines an air chamber by a free piston disposed in the cylinder, further has a suspension spring on the outside of the cylinder, and is configured to provide a desired damping effect by sliding of the piston part. A slide cylinder is installed on the outer periphery near the other end of the cylinder, and the suspension spring has a repulsive force in the extension direction, one end of which is latched to the outer periphery of one end of the cylinder from the axial direction, and the other end is The other end of the cylinder is locked to a spring receiver arranged on the outer periphery, and the spring receiver is attached to the rear end of the piston rod and is connected to the other end of the cover extending toward the other end of the cylinder. A hydraulic shock absorber characterized in that the inner circumference thereof is in sliding contact with the outer circumference of the slide cylinder. (2) The hydraulic shock absorber according to claim 1, wherein the cover attached to the rear end of the piston rod is formed to be slidable in the axial direction of the cylinder at the attached location. (3) A spring holder that locks the other end of the suspension spring is attached to the rear end of the piston rod and is connected to the other end of the cover that extends to the rear end of the cylinder, and is arranged on the outer periphery of the other end of the cylinder. A hydraulic shock absorber according to claim 1, wherein the hydraulic shock absorber is slidably formed on a casing.