JPS63140138A - Buffer - Google Patents

Abstract

PURPOSE:To obtain a shock absorber which performs a buffer action depending upon the moving direction of a road by pressing a friction member by a pressing member when the rod is moved in one direction and decreasing the pressure to the friction member when the rod is moved in the other direction. CONSTITUTION:When a cushion rod 8 is moved largely upward, a buffer rubber 23 is brought into contact with an upper spring bearing 20 to be deformed. With the upward movement of the cushion rod 18, the first piston 28 is slid while it is strongly pressed to the inner surface of a front fork 11 by expanding force received from an expansion ring 30, so that the first piston slides with frictional resistance larger than the second piston 29. When the cushion rod 18 is moved downward, a taper surface 29a of the second piston 29 is strongly pressed to a taper surface 28a of the first piston 28 to expand the piston 28 outward.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shock absorber that performs different buffering effects when a rod moves in one direction and when the rod moves in the other direction with respect to the shock absorber body. .

[Prior Art] This type of shock absorber is widely used, for example, to absorb shock from the wheels of motorcycles and automobiles, and has an excellent shock absorbing effect in order to promote the convergence of Subrinog waves after absorbing the shock. Do your best.

Generally, such a buffer is called an oil tambour, and is made by sealing oil in a cannon.
It is designed to avoid changing the oil flow resistance depending on the direction of the moving force of the rod. Since the oil damper has such a unique configuration, it is impossible to deny that its configuration is iu ht. i′i convenient small size C) After some hesitation, we proposed a simple friction type shock absorber (damper device for shock absorbers) (Utility Model Application No. 59-27341).This shock absorber has almost the same axis center position and can be moved inward and outward. In a device in which a buffer is interposed between a cylinder and a sliding rod that fit together, a sliding contact piece inscribed in the cylinder is attached to the sliding rod, and the sliding contact piece has a tapered shape on the side in the direction of shock absorption. When the sliding rod moves toward the tapered side of the sliding contact piece, the sliding contact piece makes sliding contact with relatively small frictional resistance, while the sliding rod moves in the opposite direction. When moving in the direction, the sliding contact pieces come into sliding contact with relatively large frictional resistance.

[Problems to be Solved by the Invention] By the way, although the previously proposed shock absorbers mentioned above have a simple friction type structure, the wear of the sliding contact pieces tends to be concentrated at the tips, and there is still room for improvement. was there.

This invention solves these problems.

[Means for Solving the Problems] The shock absorber of the present invention is attached to a rod, can be freely displaced by a predetermined ligament along the moving direction of the rod, and has a predetermined frictional force with a surface on the shock absorber main body side. a friction member that is provided at a fixed position of the rod, and that is opposite to one end of both ends of the friction member in the direction of movement of the rod, and that the rod contacts the other end of the friction member; a suppression member that presses one end of the friction member when a displacement occurs between the rod and the friction member; one end of the friction member; The damping member is formed on at least one of the surfaces facing each other, and when the suppressing member presses one end of the friction member, the friction member is shifted and pressed in the direction of contact with the shock absorber main body. It is characterized by having an inclined surface.

[Operation] In the shock absorber of the present invention, when the rod to which the friction member and the pressing member are attached moves in one direction, the friction member is strongly pressed by the suppressing member, and the peripheral surface of the friction member is moved toward the shock absorber body side. The rod is strongly pressed to increase the frictional resistance, and when the rod moves in the other direction, the suppression of the frictional member by the suppression member is reduced to reduce the frictional resistance. This achieves different damping effects depending on the direction of movement of the rod.

[Example] Hereinafter, one embodiment of the present invention will be described based on the drawings.

This example is an example of application as a shock absorber installed in a front fork of a two-wheeled vehicle.

In the figure, 11 is a pipe-shaped front fork of a two-wheeled vehicle, and the base end of an axle mounting arm 12 is rotatably attached to the lower end of the front fork. The base end of this axle mounting arm 12 is bifurcated, and each of the bifurcated tips is attached to the lower end of the front fork 11 by a bearing.

An axle 13 is attached to the tip of this axle attachment arm 12. Furthermore, a plate 14 extending downward along the axis of the front fork 11 is fixed to the lower end of the front fork 11 . In this example, the plate 14 is fixed to one of the two bearings to which the axle mounting arm 12 is attached. One end of a first link 15 having a crank shape in the width direction is rotatably attached to the lower end of the plate 14.

Both ends of a second link 16 are relatively rotatably attached to the intermediate portion of the axle mounting arm 12 and the tip of the first link 15, respectively. This second link 16 is
When the front fork 11 is viewed from the front in the direction of travel of the two-wheeled vehicle, that is, when the front fork 11 is viewed from the front in the direction of the arrow in FIG.
It is attached so that it is located on the axis of 1. In order to attach it in this manner, the first link I5 is crank-shaped, and the intermediate portion of the axle mounting arm 12 is bulged (see FIG. 5).

With this configuration, the proximal half of the axle mounting arm 12, the plate 14, the first link 15, and the second link 16 form a so-called four-section parallel link.

1. Therefore, in a total of four link parts between each node, the ones facing each other have the same length, and the proximal half of the axle mounting arm 12 and the first link 15
are parallel, and the plate 14 and the second link 16 are parallel. Further, the lower end of the second link 16 is
It extends below the lower end of the front fork 11 and has an L-shape as a whole.

A cushion rod 18 of a shock absorber 17 according to the present invention is connected to the lower end of the second link 16 so as to be relatively rotatable. The shock absorber 17 itself is attached to the front fork 1
The shock absorber body 1 is installed in the front fork 11 of the shock absorber body, and is designed to act as a buffer against the shock absorber rod 18 that moves up and down within the front fork 11.

In the shock absorber 17, the upper end of the cushion rod 18 is received by a spherical seat 19a on the lower surface of the spring receiver 19. The upper end of the cushion rod 18 is a spherical portion 18a, and can be tilted in any direction using a spherical seat 19a of the spring receiver 19 as a fulcrum. A spring receiver 20 is fixed at a fixed position above the front fork 11, and this upper spring receiver 20
and the lower spring receiver 19, the spring 21
is included. The upper spring receiver 20 is stopped by a convex portion 11a formed by inwardly deforming the wall portion of the front fork 11, and is prevented from moving upward. Further, a convex portion 20a is formed on the lower side of the spring receiver 20 and is located inside the spring 21 to position the spring 21. Further, a spacer 22 located inside the spring 21 is attached above the lower spring receiver 19, and a pointed cushioning rubber 23 is attached above the spacer 22.

A clip 24 is attached to the intermediate fixed position of the cushion rod 18.
However, the fitting is fixed. A washer 25, a spring 26, and a guide plate 27 are sequentially set on the upper part of the clip 24 so as to fit on the outside of the cushion rod 18. The spring 26 is
It is stored between the washer 25 and the upper inner flange 27a of the guide plate 27, and the guide plate 2
It is positioned by the cylindrical portion 27b of No.7.

An outer flange 27c is formed on the lower side of the guide plate 27, and a first piston (friction member) 28 and a second piston are fitted onto the outer side of the cushion rod 18 on this outer flange 27c. piston (pressing member) 2
9 is set.

The first piston 28 is molded from a friction part material,
It is an assembly of pieces divided into two or three parts along the circumferential direction of the cushion rod 18, and inside each piece is expanded so that each piece is urged outward and pressed against the inner surface of the front fork 11. A ring 30 is attached. Further, the upper end of the first piston 28 is a tapered surface 28a that slopes downward toward the inside of the front fork 11. On the other hand, the second piston 29 is
The cushion rod 1 is formed of a friction part material and
It is a cylindrical integral body that fits on the outside of the spherical part 18a of the front fork 8, and a tapered surface 29a that slopes downward toward the inside of the front fork 11 is formed at its lower end.
It matches the tapered surface 28a of the first piston 28.

Next, the effect will be explained.

The axle mounting arm 12 has a third
As shown by a solid line or a two-dot chain line in the figure, it swings around its base end. Along with this rocking, the axle mounting arm 1
2 operates, and the upper half of the second link 16 constituting the parallel link remains parallel to the plate 14, that is, parallel to the axis of the front fork 11. While maintaining this state, it is displaced as shown by the solid line or the two-dot chain line in the figure. Therefore, the lower end of the second link 16 pushes or pulls the cushion rod 18 substantially along the axis of the front suspension 11. The reason why the lower end of the second link 16 is not completely displaced along the axis of the front fork 11 is because
This is because the second link 16 is displaced while drawing a slight arc due to the configuration of the parallel link. Therefore, the cushion rod 18 moves up and down while slightly rocking around the spherical portion 18a at its upper end. The lower surface of the spring receiver 19 serves as a spherical seat 19a to allow the swinging motion.

The shock absorber 17 performs different shock absorbing effects on the cushion rod 18, which moves up and down in this way, when it moves upward and when it moves downward. This is because it has an excellent buffering effect similar to an oil damper.

Therefore, first, the buffering effect when the cushion rod 18 moves upward will be explained.

When the cushion rod 18 moves upward from the state shown by the solid line in FIG. 3, the spring 21 is compressed. And, as shown by the two-dot chain line in the same figure, the Kutsunoyon rod I
8 moves upward significantly, the buffer rubber 23 hits the upper spring receiver 20 and is deformed. Further, as the cushion rod I8 moves upward, the eleventh and second pistons 28 and 29 slide while remaining in contact with the inner surface of the front fork 11. The first piston 28 is expanded by the expansion force received from the expansion ring 30, causing the front fork 11 to move.
Since it slides while being strongly pressed against the inner surface of the second piston 29, it slides with greater frictional resistance than the second piston 29. Therefore, the tapered surface 28a of the first piston 28 tends to separate from the tapered surface 29a of the second piston 29. As a result, the first and second pistons 28, 29 individually perform a damping effect with their respective frictional resistances.

In this way, when the cushion rod 18 moves upward, the initial cushioning effect is achieved by the elasticity of the spring 21 and the cushioning rubber 23 and the frictional resistance of the eleventh and second pistons 28 and 29.

Next, the buffering effect when the cushion rod I8 moves downward will be explained.

When the cushion rod 18 moves downward from the state indicated by the two-dot chain line in FIG. Slide the
The frictional resistance created at that time acts as a buffer. As described above, the first piston 28 slides with greater frictional resistance than the second piston 29, so this time, the second piston 29 slides with respect to the tapered surface 28a of the first piston 28. The tapered surface 29a will be strongly pressed. As a result, the lower end of the second piston 29 enters inside the first piston 28 along the tapered surface 28'a (in the direction of arrow B in FIG. 4), forming the first piston 28. Move the pieces outward (fourth
Spread it out in the direction of arrow C in the figure). As a result, the circumferential surface of the first piston 28 is applied to the front fork 1 with an even stronger force.
It is pressed against the inner surface of 1 and has strong frictional resistance, providing a large buffering effect.

In this way, when the Kunjong rod 18 moves downward, the first and second pistons 28, 29 cooperate,
This provides a buffering effect due to large frictional resistance, and provides a different buffering effect than when the cushion rod 18 moves upward.

By the way, the shock absorber 17 of this embodiment is configured inside the front fork 11 of a two-wheeled vehicle so that the front fork 11 serves as the shock absorber main body, so the structure around the front fork 11 is simplified and the appearance is simplified. This is advantageous in terms of design since it can be made in good condition and a large space can be secured around the front fork 11.

Note that it is not necessary to configure the shock absorber I7 inside the front fork II, and the main body of the shock absorber 1817 may be configured separately from the front fork 11, and the shock absorber 17 can be used as a shock absorber for various purposes. Applicable to a wide range of fields.

Further, the second piston 29 does not necessarily need to be molded from the friction material, and may be formed integrally with the Kunjin rod 18. In short, by pressing the first piston 28, the first piston 28 is moved to the shock absorber 17.
Any material may be used as long as it can be pressed strongly against the main body of the device to increase the friction resistance. Therefore, as long as this function is achieved, the first. An inclined surface may be formed on at least one of the mutually opposing surfaces of the second pistons 28, 29. Also, 1st. The second piston 28°29 is
The second piston 29 does not necessarily have to be cylindrical.
It is sufficient that the first piston 28 is strongly pressed against the main body of the shock absorber 17 when the first piston 28 is pressed.

[Effects of the Invention] As explained above, in the shock absorber of the present invention, a friction member and a pressing member are attached to the rod that reciprocates with respect to the shock absorber body, and when the rod moves in one direction, the pressing member causes friction. The structure is such that when a member is pressed, the friction member is strongly pressed against the shock absorber body side, and when the rod moves in the other direction, the suppression of the friction member by the pressing member is reduced, so in the former case, the frictional resistance is increased. In the latter case, it is possible to reduce the frictional resistance, and as a result, it is possible to provide a shock absorber with a simple friction-type structure that achieves different shock absorbing effects depending on the direction of movement of the rod.

Moreover, the structure is such that the shock absorbing effect can be varied by changing the contact pressure of the friction member against the shock absorber body.
Local wear of the friction member can be avoided by setting a large contact surface of the friction member with respect to the shock absorber body. Therefore, the desired buffering effect can be maintained for a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a side view of a two-wheeled vehicle equipped with a shock absorber according to an embodiment of the present invention, Fig. 2 is an enlarged partially cutaway view of the same embodiment, and Fig. 3 is a side view of a motorcycle equipped with a shock absorber according to an embodiment of the present invention.
The figure is an enlarged view of the main part of the same embodiment, and FIG. 4 is a perspective view of the same embodiment. 11...Front fork (buffer body), 1
8... Cushion rod (rod), 21...
...Spring, 23...Buffer rubber,
28...First piston (friction member), 28a
...Tapered surface (slanted surface), 29...
Second piston (pressing member), 29a...tapered surface (slanted surface), 30...expansion ring. Reference person Honda Motor Co., Ltd. Figure 8

Claims (1)

[Scope of Claims] A friction member attached to a rod, movable within a predetermined range along the moving direction of the rod, and in contact with a surface on the shock absorber main body side with a predetermined frictional force; The rod is provided at a position opposite to one of the two ends of the friction member in the direction of movement of the rod, and the rod moves toward the other end of the friction member so that the rod and the a pressing member that presses one end of the friction member when a deviation occurs between the friction member; and at least one of the opposing surfaces of the one end of the friction member and the pressing member. and an inclined surface formed on one end of the friction member to shift and press the friction member in the direction of contact with the shock absorber body when the pressing member presses one end of the friction member. buffer.