JPS58203243A - Spring load adjusting device in hydraulic buffer - Google Patents

Abstract

PURPOSE:To provide a spring load adjusting device which can be applied to high load and be remote-operated by adjusting spring load with oil pressure or air pressure, and bearing the spring load with a housing after adjusting. CONSTITUTION:A pressure chamber 12 is partitioned between the outer periphery of a cylinder 2 and the inner periphery of a housing 10, and a cylindrical piston 13 is inserted in the pressure chamber 12 in such a manner as to move up and down. An adjusting cam 28 comprises a cylinder 29, an upper cam member 30 secured to the cylinder 29, and the lower cam member 31, wherein a plurality of cam surfaces engaged with a stopper 25 of a housing 10 are formed on the lower surface of the upper cam member 30, and the upper surface of the lower cam member 31 is provided with four saw blades engaged with a pin of the housing 10 to turn the adjusting cam 28.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spring load adjustment device, and more specifically to a hydraulic shock absorber for a front fork of a two-wheeled vehicle, which allows the initial pressing force to be set to an appropriate value depending on the weight of the vehicle body, road conditions, etc. This invention relates to a spring load adjustment device for a device.

Generally, front forks for two-wheeled vehicles are formed by an oil damper and a coil spring in order to alleviate the vibrations and shocks that the vehicle body receives from the road surface while driving. It must be set to an appropriate value depending on the conditions, etc., and a coil spring load adjustment device is also required to adjust the initial pressing force according to the weight of the person riding on the vehicle and the weight of the luggage. .

For this reason, the present applicant has developed a conventional spring load adjusting device disclosed in, for example, Japanese Unexamined Utility Model Publication No. 154839/1983.

This one has two upper and lower cam members rotatably arranged,
An operating rod is inserted into the inside or outside of this cam member so as to be able to move up and down, and each of the two cam members has a cam surface that faces each other, and a pin that projects toward the cam surface side is provided on the operating rod. When the operating rod is pushed downward, the pin hits the cam surface of the lower cam member and rotates the lower cam member and the upper cam member that interlocks with it. Then, when the operating rod's pressing force is stopped, the pin moves upward. The pin meshes with another cam surface of the cam member, and the spring load is set according to the height of the cam surface with which the pin meshes.

However, although the above spring load adjustment device is easy to operate and manufacture, the pin carries the spring load, and in the case of a high spring force, the pin itself may not be strong enough, causing the pin to come off, or It may bend and cause discomfort.

Therefore, in order to give strength to the pin, this drawback can be solved to some extent by increasing the outer diameter of the pin, but on the other hand, it is necessary to increase the distance between the upper and lower cam members, and the length of the hydraulic shock absorber itself in the longitudinal direction is increased. The drawback is that it becomes long and large.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a spring load adjusting device for a hydraulic shock absorber suitable for use in a front fork or rear cushion unit of a motorcycle, which can support a high spring force.

To achieve this objective, the present invention provides two upper and lower cam members and a housing that mechanically carry the spring load.

It is characterized by comprising a piston that pushes up the cam member and the spring seat using hydraulic or pneumatic pressure, and a pin that causes the cam member to rise and engage with the nine o'clock cam surface to rotate the cam member.

Embodiments of the present invention will be described below with reference to the drawings.

The hydraulic shock absorber (1) has a cylinder (2) and a cylinder (2).
A piston rod (4)' is slidably inserted into the piston (3) via the piston (3), and brackets (51+61) are provided at the end of the piston rod (4) and the end of the cylinder (2).
A spring seat slidably inserted into the outer circumference of the cylinder.
It consists of a spring seat (8) provided on the upper part of the piston rod and the spring seat +7118+, and a suspension spring (9) telescopically interposed between these spring seats +7118+, and the bracket (5) is held on the vehicle body side of a motorcycle or the like. The other bracket (6) is held on the wheel side, and the suspension spring (9)
always urges the piston rod (4) in the direction of extension.

The present invention adjusts the initial spring load of the suspension spring (9) in the hydraulic shock absorber (1) by selecting the height position of the lower spring seat (7).

A cylindrical housing H is disposed at the bottom of the cylinder (2) at the center of the mouth, and this housing is connected to the cylinder +2+
(It is removably fixed to lljl via a snap ring α force. The housing a1 can be fixed by welding or other known methods.

A pressure chamber (12) is defined between the outer periphery of the cylinder (2) and the inner periphery of the housing 01m, and a cylindrical piston (2) is inserted into this pressure chamber (6) so as to be able to move up and down. are sealed via seals 04 Qd 06 provided on the inner peripheries of the housing (II) and the piston (2).

At the top of the piston (2) there is a locking part (13) that protrudes outward.
a) is provided.

In the pressure chamber (6), hydraulic or pneumatic pressure is supplied and discharged from a through hole α provided in the housing α at the bottom of the piston (toward),
For example, when hydraulic pressure is introduced, the piston (to) rises against the suspension spring (9), and when the four oil pressure is discharged, the piston α
(2) is adapted to be lowered by the restoring force of the suspension spring (9).

The through hole α force is led via the hole λα→ to a hydraulic or pneumatic pressure source. In Figure 1, a pump (see) is connected as a pressure source, and this pump (see) consists of a cylinder holder and a piston (c) movably inserted into the cylinder (a), which is connected to the piston. When the screw rod (2) is rotated in one direction, the piston @ moves to the right.

The oil in the oil chamber (2) is led to the pressure chamber (l, 1) via the hose α, and when the screw rod (c) is rotated in the other direction, the piston &
j moves to the left so that the oil in the pressure chamber (to) is sucked into the oil chamber (to).

As shown in Figures 1 and 2, the housing 0■ has a step (C) formed on its inner periphery, a plurality of stoppers (C), for example four, protruding upward from the upper end, and a stepped portion (C) on the outer periphery of the body. A plurality of locking grooves (2) are formed in the vertical direction, and one or two opposing pins (5) are installed in the horizontal direction adjacent to the stopper (A).

It is also possible to provide the pins (b) close to all the stoppers (c). Also, this pin (support) has a hole in the cylindrical body (
29a).

An adjustment cam (2) is disposed at a position facing the outer periphery and upper end of the housing 00 so as to be movable in the rotational and axial directions.

This adjustment cam (c) consists of a cylindrical body and an upper cam member (a) fixed to the inner circumference of this cylindrical body at an arbitrary interval Y.
and a lower cam member G11, and these cylindrical bodies and the cam member Gυ are configured to move simultaneously in the vertical direction and in the rotational direction.

The upper cam member (A) is made of a cylindrical body, and a number of cam surfaces αl hT C, d provided in a stepped manner on its lower surface face the stopper (A) of the housing a, and this stopper (C) is connected to the cam surface. It selectively engages with any one of α, b, c, and d, and the spring load is set according to the height of the selected cam surface.

The cam surfaces α, A, C, and d form one set, and each set is provided at four locations on the lower surface of the upper cam member (G).

A large number of cam surfaces having different heights may be provided in the circumferential direction on the lower surface of the upper cam member (1), and the number of each set can be formed arbitrarily.

The upper end of the lower cam member C31+ has four saw teeth e,
f, ), h are provided toward the top, and this sawtooth g
The upper tapered surfaces P, Q, R, and S of j, y, and A face the cam surfaces α, b, c, and d and the pin (c), and the lower cam member! 3+) rises, the pin (B) comes into contact with one of the tapered surfaces P, Q, R, and S. At this time, since the bottle (A) is fixed, the tapered surface is pushed by the pin @ and the cam member (
g) 011 rotates in one direction.

A hole C33 is bored in the body of the lower cam member Gυ in the radial direction, and a positioning mechanism (to) consisting of a locking ball (to) and a spring (b) is inserted into this hole (to), and these The positioning mechanism (to) selectively engages with one of the locking grooves (c) provided on the outer periphery of the housing 0ω when the lower cam member C311 rotates, and thereby the adjustment cam (to)
This positioning mechanism (3
By detecting the two positions, the magnitude of the spring load can be confirmed.

The positioning mechanism (c) is prevented from being removed by a lid (g).

The upper end of the locking part (13a) of the piston (to) faces the cam surface of the upper cam member (g), and the upper end of piston 0 faces the spring seat (7). , At this time, the gap between the upper cam member (to) and the locking part (13α) and the upper end of the piston α3 and the spring seat (the monthly gap is l!, >I!
.

As a result, the piston (to) rises and the nine o'clock spring seat (7) and suspension spring (9) are pushed up first, and the upper cam member (1) is pushed up afterwards. Even when the spring seat (force) and the upper cam member (to) are adjusted, a gap is formed between the spring seat (force) and the upper cam member (total), and as a result, the spring force of the suspension spring (9) does not act on the entire adjustment cam holder. The adjustment cam (to) can be rotated freely (Fig. 1) Next, the operation will be described.

The states shown in figures 1 and 3 are the stopper of the housing α (
c) meshes with the cam surface α of the upper cam member (1), and has a spring load corresponding to the height of the cam surface a.

From this state, for example, when the stopper (c) is engaged with the cam surface C and the spring load is adjusted to correspond to the cam surface C, the following procedure is performed.

First, when, for example, hydraulic pressure is supplied from a pressure source to the pressure chamber (2), the piston Ql rises and its tip touches the spring seat (
Push up the force as much as possible to the position where it hits the locking pin 07) and keep the suspension spring (9) flexed. On the other hand, the locking part (13α) of the piston oj is slightly delayed and the upper cam member (1)
push up.

When the upper cam member (A) is pushed up, the cylindrical body - and the lower cam member (311) that are connected to it are also pushed up together, and the pin (C) provided on the housing +11 is moved to the lower member CD.
This corresponds to the tapered surfaces P, Q, R, and S of. At this time, there is also a gap between the pulling seat (force and the upper cam member (1) '/ + 1
Since there is a gap corresponding to a difference of 2, the adjustment cam (c) consisting of the cam member (1) C1ll and the cylindrical body can freely rotate. Therefore, as shown in Figure 3, the pin (A) hits, for example, the position m of the tapered surface Q.

In this state, if the adjustment cam (c) rises further, the pin (a)
Since is fixed, the adjustment cam 2 rotates when pushed by the pin (a), and the pin slope is displaced along the tapered surface Q to the position 2.

This position is opposite to the cam surface C, and this position allows the position of the positioning mechanism to be confirmed from the outside.

When the pin (B) reaches position n, the pressure oil in the pressure chamber (6) is removed, and the lifting of the piston Ql and the rotation of the adjustment cam 2 are stopped.

The fact that the pin (c) is at position n means that the cam surface C of the upper cam member (1) faces the stopper (c).

On the other hand, when the pressure in the pressure chamber (2) is released, the piston (to) is pushed downward via the spring seat (7) by the restoring force of the suspension spring (9), and the spring seat (7) is further pushed downward by the upper cam member ( The adjustment cam (C) is pushed downward while in contact with 1), and the stopper (C) engages with the cam surface C. In this state, the adjustment cam (C) no longer moves due to the engagement of the stopper (C) and the holding force of the positioning mechanism (C).
The initial spring load of the suspension spring (9) is set according to the height of the cam surface C.

In this case, the suspension spring (9) is entirely supported by the housing Q11 via the upper cam member (2) and the stopper (C), and even if the spring load is high, it can sufficiently withstand it.

As described above, according to the present invention, (1) since the housing carries the spring load, it can be used satisfactorily even for high-load applications.

■Since the piston is not pushed up by hydraulic or pneumatic pressure, the spring load can be adjusted, so remote control is possible, and the installation of the hydraulic shock absorber can be adjusted regardless of its position.

■It can be adjusted simply by driving the piston, and since the piston is driven by hydraulic or pneumatic pressure, adjustment is automatic.
In addition, since no force is required from the operator, operability is good.

[Brief explanation of the drawing]

The attached drawings relate to embodiments of the present invention, in which Figure 1 is a longitudinal sectional front view of a hydraulic shock absorber using the spring load adjustment device of the present invention, Figure 2 is an exploded perspective view of an adjustment cam, and Figure 3 is a housing. Figure 4 is a cross-sectional plan view of the lower cam member, and Figure 4 is a developed view of the adjustment cam and housing. (2)...Cylinder, αl...Housing, (In
... Piston - (c) ... φ stopper, @... pin. (c)...adjustment cam, wire, cylinder, (b) Gll
---Cam member, P, Q, R, 5---Tapered surface, a, h
, c, d *** Cam surface. Representative Patent Attorney Izumi Ohno

Claims (2)

[Claims] (1) A housing is arranged around the outer periphery of the cylinder, a piston is slidably inserted between the cylinder and the housing, and a cylindrical body and two upper and lower cam members provided inside the cylindrical body are attached to the outer periphery of the housing. An adjustment cam is disposed to be movable in the vertical and rotational directions, and the upper part of the housing has a stopper that faces one of the cam surfaces of the upper cam member, and the body of the housing has a stopper that faces one of the cam surfaces of the lower cam member. Spring load adjustment in a hydraulic shock absorber in which a pin facing the surface protrudes so that the piston pushes up the spring seat before the upper cam member when the piston rises, and the piston is driven up and down by hydraulic or pneumatic pressure. Device. (2) A locking portion is provided on the outer periphery of the piston, and the gap between the upper end of the piston and the spring seat and the gap J between the locking portion and the upper cam member are l/”:)l. A spring load adjusting device for a hydraulic shock absorber according to claim 1, which is formed as follows.