JPS589828Y2 - Front fork valve device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pulp device for a front fork, and more specifically, the rebound damping force is generated at the orifice of the valve,
The present invention relates to a front fork pulp device suitable for use in two- and three-wheeled vehicles, in which oil flows smoothly from the inner and outer circumferences of the valve and the orifice during compression.

In this type of conventional front fork, an inner tube is slidably inserted into an outer tube, and a piston is provided at the bottom of this inner tube. A valve case is provided at the lower end of the inner tube, and a cross-sectional valve is built into the valve case so as to be movable up and down. Proportionality characteristics are exhibited by the annular gap.

However, with conventional valve mechanisms like this, the annular gap is easily affected by temperature, causing valve noise when operating.
Another disadvantage is that the valve response is poor and the free flow of oil is poor during compression.

Therefore, the purpose of this invention is to solve these drawbacks by creating a pulp device for the front fork that has less influence on the damping force characteristics due to temperature, has good oil inflow on the pressure side, has a light valve, and has good response. It is to provide.

The implementation of the present invention will be explained below with reference to the drawings.

An inner tube 2 is slidably inserted into the outer tube 1, and a hollow cylinder 3 stands up inside the inner tube 2 from the center of the lower part of the outer tube 1, and is provided on the outer periphery of an auxiliary piston 4 at the upper end of the hollow cylinder 3. The slide member 5 is in contact with the inner periphery of the outer tube 1, and the piston I, which is fixed by a stopper 6 at the lower end of the inner tube 2, is in sliding contact with the outer periphery of the hollow cylinder 3.

A bracket 8 is fixed to the lower end of the outer tube 1, and an axle on the wheel side is clamped to the eye 9 of the bracket 8.

The piston 7 also defines two upper and lower liquid chambers 10 and 11 in the outer tube 1 and inner tube 2, and a liquid chamber 12 is formed in the hollow cylinder 3.
An air spring or coil spring is interposed above the inner tube 2 to constantly push the inner tube 2 toward the vehicle body.

An oil lock member 13 having a T-shaped cross section is slidably inserted into the outer periphery of the hollow cylinder 3.
3 is provided with upper and lower stoppers 14, 15, and when the inner tube 2 is fully extended, the upper stopper 15 comes into contact with the auxiliary piston 4, and the lower stopper 14 comes into contact with the pulp stopper 16 on the piston 1. .

A return spring 1γ is interposed between the oil lock member 13 and the auxiliary piston 4, so that the oil lock member 13 is always
is pushed down to the snap ring 18 position.

Also, an outer tube 1 is installed on the outside of the oil lock member 13.
A spring 19 that exhibits composite spring characteristics with a suspension spring (not shown) interposed between the inner tube 2 and the inner tube 2 is arranged in parallel with the return spring 17.

When the front fork starts compressing, the spring 19 acts on the valve stopper 16 to improve the compression operation, and when it is extended, the pulp stopper 16 first collides with the spring 19 and gradually expands while bending it. When the pulp stopper 16 is further extended in this state, it comes into contact with the lower stopper 14 of the oil lock member 13, and oil flows out from the small gap between the two stoppers 14 and 16. While the oil is locked, the upper stopper 15 is moved to the lower surface of the auxiliary piston 4. Extend to the position where it touches.

Next, the valve mechanism, which is the gist of the present invention, will be explained in detail.

A pulp stopper 20 having a hole 19 in the center is disposed inside the lower part of the inner tube 2, and its upper end is supported by the stepped portion of the inner tube 20, and its lower end is supported by the stopper 6.

This stopper 6 bends the lower end of the inner tube 2 to prevent it from falling off downward.

A valve cap 21 is supported within the valve stopper 20, a piston 7 is fixed between the valve cap 21 and the stopper 6, and a valve 22 is loosely fitted between the piston I and the valve cap 21 so as to be movable up and down. There is.

However, this valve 22 has its upper surface and pulp cap 21
It is also possible to use a leaf valve with a low initial load interposed therebetween to press the valve 22 toward the piston γ side.

The valve cap 21 is formed into a star shape, with gaps spaced at equal intervals around the periphery, a plurality of feet 24 hanging downward, and a hole 25 and a plurality of uneven portions 26 formed in the center. .

A through hole 27 is bored in the outer periphery of the piston I to allow the plurality of liquid chambers 10 and 11 to communicate with each other, and a valve 22 with a large central hole 29 and a surrounding orifice 28 is bored at the upper end of the through hole 25. is arranged so that it can be opened and closed freely.

In the above valve device, when the inner tube is extended, the liquid chamber 1
0 oil flows from the holes 19 and 25 to the orifice 28 of the valve 22.
The liquid flows out into the liquid chamber 11 through the hole 27, and at this time, the action of the orifice 28 generates a damping force during expansion.

Also, during compression, the oil in the liquid chamber 11 pushes the valve 22 up through the hole 27 and bends it, and at this time the valve 22 comes into contact with the convex portion 26Vc of the valve cap 21, but the valve cap 21 is shaped like a star and there is no gap. Moreover, since a plurality of uneven portions 26 are formed, the liquid flows from these gaps through the holes 19 to the liquid chamber 10 side.

Therefore, the oil from the hole 2T flows out through the gap in the valve cap 21 from the inside and outside of the valve 22 and the orifice 28, so that it flows smoothly and in large quantities with extremely little resistance.

This is almost the same when a spring with a low initial load is set on the upper surface of the valve 22.

Also, since the valve 22 has a large hole 29 in the center, it does not slide directly into the hollow cylinder, and also has good responsiveness due to its shape.

As mentioned above, the valve device of the present invention: ■ uses a thin-blade orifice, so there is little effect on damping force due to temperature, and ■ has good free flow characteristics, so it can maintain rebound damping force even when compression side damping force is low. The valve is a plate valve, so it is light in weight and has good valve response, which eliminates the valve closing noise.

[Brief explanation of drawings]

The attached drawings relate to one embodiment of the present invention, and FIG. 1 is a partially cutaway vertical side view of the front fork, FIG. 2 is a partially enlarged view of FIG. 1, and FIG. 3 is a vertical side view of the pulp stopper. 4 is a vertical side view of the valve cap, FIG. 5 is a vertical side view of the non-return valve, and FIG. 6 is a vertical side view of the piston. 2... Inner tube, 7... Piston, 20.
...Pulp Stopper, 21...Valve Chara 7",
25...hole, 26...irregularity, 27...hole, 28.
...orifice.

Claims (2)

[Scope of utility model registration request] (1) A valve stopper is fixed to the lower end of the inner tube, a valve cap with a hole in the center and multiple irregularities is fixed to the lower end of the valve stopper, and multiple holes are formed around the lower part of the valve cap. A front fork pulp device has a fixed piston with a fixed hole, and a movable valve with a large hole in the center and an orifice around the circumference between the piston and the valve cap. (2) A front fork valve device according to claim (1), wherein the valve is made of sheet pulp.