JPH0351932B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a damping force adjusting device for a hydraulic shock absorber.

Hydraulic shock absorbers used in motorcycles, especially those used for rear wheels, generally have a piston fitted into a cylinder filled with oil, an orifice that passes through the piston in the axial direction, and an opening degree of the orifice. The buffer force is adjusted by controlling the amount of oil passing through the orifice by adjusting the opening degree of the orifice using the needle valve. Adjustment of the needle valve is performed from the outside via a push rod that passes through the axis of the piston rod by screwing an adjustment nut screwed onto the outer end of the piston rod. be.

However, the adjustment of the needle valve with this adjustment nut is very delicate, and if an amateur general user performs the adjustment over the entire adjustment range of the adjustment nut, it may sometimes be difficult to restore the needle valve to its original normal state. can be difficult.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, an object of the present invention is to provide a shock absorbing force adjusting device for a hydraulic shock absorber that can be easily handled by general users.

The present invention achieves the above object by fitting a piston into a cylinder sealed with oil, providing an orifice penetrating the piston in the axial direction and a needle valve for adjusting the opening degree of the orifice, and connecting the needle valve to a piston rod. In a damping force adjustment device for a hydraulic shock absorber, fine adjustment is made by screwing an adjustment nut screwed onto the outer end of the piston rod through a push rod that penetrates the shaft center of the hydraulic shock absorber. The present invention is characterized in that an engaging element whose relative angle around the center can be changed is mounted, and the rotatable range of the engaging element is restricted to a certain range by a stopper.

The present invention will be explained below with reference to an embodiment of a hydraulic shock absorber provided in a motorcycle shown in the drawings.

In FIG. 1, 1 is a main frame, 2 is a rear arm, and 3 is a rear wheel. A shock absorber 4 provided with a shock absorbing force adjusting device according to the present invention is connected between the rear part of the main frame 1 and the upper end of the rear arm 2.

As shown in detail in FIGS. 2 to 4, the buffer 4
A free piston 6 is fitted into the cylinder 5 constituting the cylinder 5, and the inside thereof is divided into an oil chamber 5a filled with oil and a gas chamber 5b filled with gas. A piston 7 is fitted into the oil chamber 5a side, and the other end of a piston rod 8 connected to the piston extends to the outside of the cylinder 5. The piston 7 is provided with an orifice 9 that penetrates in the axial direction, and a needle valve 10 faces the orifice 9 to define a constant opening degree. The other end of the needle valve 10 is connected to a push rod 11.
1 passes through the axis of the piston rod 8 and reaches the end.

A cylindrical piece 12 is screwed and fixed to the outer end of the piston rod 8. Elongated holes 13, 13 are formed at both ends of the cylindrical piece 12, and a horizontal pin 14 is inserted so as to be movable along the elongated holes 13. An adjustment nut 15 is screwed onto the outer periphery of this cylindrical piece 12, the inner side surface of this adjustment nut 15 is brought into contact with both ends of the horizontal pin 14, and the central side surface on the opposite side of the horizontal pin 14 is connected to the push rod. It is brought into contact with the end of 11. Therefore, when the adjusting nut 15 is adjusted by screwing, the push rod 11 is adjusted via the horizontal pin 14.
The opening degree of the orifice is adjusted by changing the position of the needle valve 10 facing the orifice 9.

A large number of recesses 15a are provided at equal intervals on the outer periphery of the adjustment nut 15, and a recessed groove 15b is provided along the outer peripheral end surface. This adjustment nut 1
A resin annular engaging element 16 is removably attached to the outer periphery of the needle valve 5, and by rotating the engaging element 16, the adjusting nut 15 is rotated together, and the opening degree of the needle valve 10 is adjusted. It is adjustable. This resin-made engagement element 16 has an engagement recess 16d cut out over a certain circumference on the outer circumference side, and a protrusion 16a on the inner circumference side, which is inserted into one of the recesses 15a of the adjustment nut 15. In addition to being selectively fitted, a protrusion 16b is provided on the inner circumferential end surface so that the protrusion 16b is fitted into the groove 15b of the adjustment nut 15.

Further, the engaging member 16 has a slit 16c in a part of the annular portion, and is configured to be pushed apart through the slit 16c. Therefore, in order to attach the engaging element 16 to the adjustment nut 15, the slit 16c is pushed out and placed over the outside of the adjustment nut 15, the protrusion 16a is fitted into one of the recesses 15a, and the protrusion 16b is fitted. The slit 16c may be returned to its original state by fitting the slit 16c into the groove 15b.

With the engaging member 16 mounted and fixed in this manner, a stopper 17 is provided corresponding to the engaging recess 16d, and the stopper 17 is attached to the cylindrical piece 1.
It is fixed on a plate 18 which is unrotatably fixed to 2. Therefore, the rotation range of this engaging element 16 is restricted by the stopper 17, and can only rotate by an opening angle corresponding to the circumferential length of the engaging recess 16d on the outer periphery. Therefore, the adjustment of the opening degree of the orifice 9 by the needle valve 10 is limited to the rotation range of the engager 16. In this embodiment, fine adjustment within this rotation range can be made while observing the relative position between the engagement mark 21 provided on the plate 18 and the engaging element 16.

20 is a spring stretched between the plate 18 and the spring receiver 19 fixed to the cylinder 5 side;
22 and 23 are mounting brackets, respectively.

Now, according to the above-described device, unless the engager 16 is detached from the adjustment nut 15, the engager 16
The adjustment range of the opening degree of the needle valve 10 is limited to a certain range. Therefore, by setting the position of the adjustment nut 15 by the manufacturer or a specialized maintenance shop, and by limiting the range of adjustment that can be made by the engager 16 to a range that can be easily made by an amateur general user, it is possible for general users to It is possible to create a buffer force adjustment device that is easy to use. Moreover, the convex portion 16a of the engaging element 16 is connected to the adjusting nut 15.
By appropriately selecting the position where it fits into one of the plurality of recesses 15a in accordance with the damping force adjustment range depending on the vehicle type, the shock absorbing force adjusting device can be applied to a wide range of vehicle types.

Note that the concave portion 15a and the convex portion 16 between the adjustment nut 15 and the engaging element 16 in the above-mentioned embodiment
The relationship between the grooves a and the grooves 15b and the protrusions 16b may be reversed. Further, although the needle valve 10 and the push rod 11 are connected in the embodiment, they may be separated from each other and only in contact with each other.

As described above, in the present invention, a piston is fitted into a cylinder filled with oil, an orifice passing through the piston in the axial direction and a needle valve for adjusting the opening degree of the orifice are provided, and the needle valve is connected to the piston rod. In a damping force adjustment device for a hydraulic shock absorber, fine adjustment is made by screwing an adjustment nut screwed onto the outer end of a piston rod through a push rod that penetrates the shaft core. An engaging element whose relative angle around the center can be changed is fitted, and the rotatable range of the engaging element is restricted to a certain range by a stopper, so the buffering force can be adjusted by adjusting the opening degree of the needle valve. It becomes possible to perform adjustment only within an easy range in which the engager can rotate, and it is possible to provide a shock absorbing force adjustment device that is easy for general users to operate. Furthermore, since the relative angle of the engaging element to the adjusting nut about the axis can be changed, the adjustment range can be changed as desired depending on the type of vehicle.

[Brief explanation of drawings]

FIG. 1 is a side view showing the main parts of a motorcycle equipped with a shock absorber having a shock absorbing force adjustment device according to an embodiment of the present invention, FIG. 3 is a side view taken in the direction of the arrows in FIG. 2, and FIG. 4 is a cross-sectional view along the line shown in FIG. 4...Buffer, 5...Cylinder, 7...Piston, 8...Piston rod, 9...Orifice, 10
...Needle valve, 11 ... Push rod, 12 ...
Cylindrical piece, 14... Horizontal pin, 15... Adjustment nut, 16... Engagement element, 15a... Recess, 16a...
... Convex portion, 16b... Engagement recess, 17... Stopper, 18... Plate.

Claims (1)

[Claims] 1 A piston is fitted into a cylinder filled with oil, an orifice passing through the piston in the axial direction and a needle valve for adjusting the opening degree of the orifice are provided, and the needle valve is connected to a push rod passing through the axis of the piston rod. In a shock absorbing force adjustment device for a hydraulic shock absorber, which is finely adjusted by screwing an adjusting nut screwed onto the outer end side of a piston rod, the relative angle of the adjusting nut with respect to its axis is changed. 1. A damping force adjustment device for a hydraulic shock absorber, characterized in that an engaging element is mounted thereon, and a rotatable range of the engaging element is restricted to a certain range by a stopper.