JPS59113335A - Spring force adjuster of cylindrical cushion unit - Google Patents

Abstract

PURPOSE:To manually adjust damping force easily by engaging a spring adjusting ring bearing one end of a coiled spring with a screw member coupled to one end of a damper in the above unit where a cylindrical hydraulic damper is disposed on the inside of the coiled spring. CONSTITUTION:In case of a rear wheel suspending device of a motor cycle, when a cushion unit 16 is compressed, a piston 28 is relatively moved to the left, so that oil in an oil chamber 50 flows into an oil chamber 48 through an oil path 52 and a throttle valve 54 of the piston 28. With the movement of the piston, oil in the oil chamber 50 flows in an oil sump 22, so that a free piston 74 is moved to the right, with gas in a gas chamber 76 compressed. At this time, in order to increase damping force at the time of extension, the throttle valve 54 is moved to the left through a control rod 46 to increase the passing oil resistance by turning a damping force adjusting ring 56 clockwise. In order to increase spring force, a spring adjusting ring 62 is turned in one direction to be moved to a cylinder 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical cushion unit equipped with spring force adjustment means.

In vehicles such as motorcycles, a cylindrical cushion unit in which a cylindrical hydraulic damper is provided inside a coil spring is often used. Conventionally, there are cushion units of this type in which the spring force of the coil spring can be adjusted in response to driving conditions such as changes in the amount of cargo on the vehicle.

FIG. 1 is a sectional view of a conventional screw type.

In this case, a spring receiver 3 is screwed into a small diameter screw member 2 fixed to the end of the piston rod 1, and the spring receiver 3 is fixed with a lock nut 4. However, in this screw type, since the threaded portion 2a of the threaded member 2 has a small diameter, increasing the number of threads to sufficiently withstand the spring force causes a problem in that the overall length of the cushion unit increases. There is also the inconvenience that a special tool must be used to loosen the lock nut 4 each time the spring force is adjusted.

The present invention was made in view of these circumstances, and provides a cylindrical cushion unit that is suitable for shortening the overall length of the cushion unit and that allows easy adjustment of spring force by hand without using special tools. It is an object of the present invention to provide a spring force adjustment device.

In order to achieve this object, the present invention provides a cylindrical cushion unit in which a cylindrical hydraulic damper is disposed inside a coil spring. a spring adjustment ring that is screwed onto the outer periphery of the screw member and serves as a spring holder for the coil spring; and a locking mechanism that fixes the spring adjustment ring in a predetermined position. The spring adjusting ring can be rotated by hand by setting the outer diameter of the coil spring to be smaller than the outer diameter of the coil spring.

The present invention will be described in detail below based on the illustrated embodiments.

FIG. 2 is a side view of the vicinity of a rear wheel suspension system of a motorcycle to which an embodiment of the present invention is applied, and FIG. 3 is a partially sectional side view of a beam unit. In FIG. 2, numeral 10 is a vehicle body frame, and 12 is a rear arm. The front end of the rear arm 12 is pivotally supported by the vehicle body frame 10 so as to be able to swing up and down, and the rear wheel 14 is held at the rear end. rear arm 12
The rear part of the cylinder is supported by cushion units 16 arranged in parallel.

The cushion unit 16 has a coil spring 18, a cylindrical hydraulic damper 20, etc. located inside the spring 18, and an oil reservoir 22. The damper 20 includes a cylinder 26 fixed to an upper spring receiver 24, a piston 28, and a piston rod 30.

A cylindrical member 32 is fixed to the end of the piston rod 30. Reference numeral 34 denotes a screw member having a small diameter portion 36, a large diameter portion 38, and a flange portion 40 connecting the two. The inner diameter side of the small diameter portion 36 is press-fitted into the cylindrical member 32 and fixed thereto. The large diameter portion 38 opens in the opposite direction to the cylinder 26, and both ends of a push rod 42 that crosses the cylindrical member 32 protrude within this opening. The member 32 includes a hole 44 having an elongated oval cross section in the longitudinal direction of the piston rod 20.
is formed, and the push rod 42 passes through this hole 44. A throttle control rod 46 is inserted into the piston rod 30, and one end of the control rod 46 projects into the hole 44 and comes into contact with the push rod 42. The other end of the control rod 46 is connected to the cylinder 2 by the piston 28.
The throttle valve 54 is opposed to the throttle part of the oil passage 52 that connects the first and second oil chambers 48 and 50 defined in the interior of the oil chamber 6 .
form. 56 is a damping force adjustment ring, and the member 32
is screwed into the cylinder from the side opposite to the cylinder 26, and its inner diameter part 58 is in contact with the push rod 42, while its outer diameter part 60 is bent so as to surround the opening edge of the large diameter part 38 of the screw member 34. ing.

Reference numeral 62 denotes a spring adjustment ring, which is formed into a substantially cylindrical shape so as to surround the outer periphery of the large diameter portion 38 of the screw member 34 from the cylinder 26 side, and has a threaded portion 36a formed in the small diameter portion 36 on the inner periphery side. A flange portion 64 to be screwed together is integrally formed. This seven-ring portion 64 serves as the coil spring 18.
It is a spring receiver that supports one end of the . Therefore, the diameter of the threaded portion 36a is slightly smaller than the inner diameter of the coil spring 18, and the outer diameter of the ring 62 is larger than the outer diameter of the coil spring 18.

The outer peripheral surface of the large diameter portion 38 of the screw member 34 and the ring 56.6
2 has a scale as shown in FIGS. 4 and 5.

4 shows the spring force of the spring 18 at its maximum, and FIG. 5 shows the spring force at its minimum.

In FIG. 3, 66 is a locking mechanism that locks the spring force adjustment ring 62 every rotation, and the flyge portion 4 of the screw member 34.
A coil spring 68 and a pole 70 are loaded into a concave hole provided in the ring 62, and a concave groove 7 is cut in the axial direction on the inner surface of the ring 62.
It is formed by 2.

A gas chamber 7 is formed in the oil reservoir 22 by a free piston 74.
6 and an oil chamber 78 are defined, and the oil chamber 78 communicates with the second oil chamber 50 in the 7 cylinder 26. The gas chamber 76 is filled with a pressurized gas such as nitrogen.

Next, the operation of this embodiment will be explained. When the cushion unit 16 is compressed, the oil in the second oil chamber 5o flows into the first oil chamber 48 through the oil passage of the piston 28. At this time, the oil flow resistance is small and the damping force is also small. Still piston rod 30
As the oil enters the cylinder 26, the oil flows into the oil reservoir 22 and the free piston 74 moves to compress the gas chamber 76.

When the cushion unit 16 is extended, the oil in the first oil chamber 48 is compressed, but a valve is attached to the oil passage provided in the piston 28, which generates a very large oil flow resistance. Therefore, the oil in the first oil chamber 48 flows into the second oil chamber 50 through the throttle 54.

In order to increase the damping force when the cushion unit 16 is extended, turn the damping force adjustment ring 56 clockwise when viewed from the right in Fig. 3 (Fig. 4), and push the control rod 46 to the left to tighten it. Throttle valve 54.

At this time, the oil flow resistance of the throttle valve 54 increases and the damping force increases. On the other hand, ring 5 is used to reduce the damping force during extension.
6 in the opposite direction (Fig. 5).

To increase the spring force, hold the spring adjustment ring 62 with your hand, rotate it in one direction, and move it toward the cylinder 26 (fourth
(Fig. 5), and in order to reduce the spring force, it is sufficient to rotate in the opposite direction (Fig. 5).

At this time, in FIGS. 4 and 5, the right edge of the ring 62 is connected to the threaded member 34.
Since the scale is located close to the scale attached to the large diameter portion 38, the scale can be read accurately and easily from the relative position of the two.

Also, the diameter of the threaded portion 36a of the threaded member 34 is set to the coil spring 1.
8, the diameter of the threaded portion 2a of the threaded member 2 is increased compared to the conventional one shown in FIG. For this reason, the total length of the thread that engages with the female thread of the ring 62 becomes longer, so the flange portion 64 where this female thread is provided becomes longer.
In other words, the axial length of the female thread can be reduced, and sufficient strength can be ensured without providing the opening and nut 4 as shown in FIG. Therefore, it is suitable for shortening the overall length of the cushion unit 10.

Furthermore, since the outer diameter of the spring adjustment ring 62 is made larger than that of the coil spring 18, the force required to rotate the ring 62 is reduced, and the ring 62 can be easily rotated by hand, improving operability.

As described above, the present invention forms a threaded part with a diameter slightly smaller than the inner diameter of the coil spring in the threaded member, uses the spring adjustment ring screwed into this threaded part as a spring receiver, and sets the outer diameter to the outer diameter of the coil spring. Since it is made to be stiff, the overall length of the cushion unit is shortened, and the spring force can be easily adjusted by hand with a light force. In addition, since the cam and pins are not exposed, there is no risk of your body or clothes getting caught, and the appearance is good, increasing the product value.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted sectional view of a conventional device, Fig. 2 is a view showing the usage state of an embodiment of the present invention, Fig. 3 is a partially sectional side view of a cushion unit, Figs. Figure 5 is a diagram showing the scale when the spring force is maximized and minimized. 16...Cushion;/unit, 18...Coil spring, 20...Attenuator, 30...Piston rod, 3
4... Threaded member, 36a... Threaded portion, 62... Spring adjustment ring, 66... Lock mechanism.

Claims (1)

[Claims] In a cylindrical cushion unit in which a cylindrical hydraulic damper is disposed inside a coil spring, a threaded member is fixed to one end of the damper and has a threaded portion on the outer periphery having a slightly smaller diameter than the inner diameter of the coil spring; A spring adjustment ring that is screwed into the outer circumference of the member and serves as a spring holder for the coil spring, and a locking mechanism that fixes the spring adjustment ring in a predetermined position, the outer diameter of the spring adjustment ring being adjusted to the outer diameter of the coil spring. A spring force adjustment device for a cylindrical cushion unit, which is characterized in that it can be manually rotated as a diameter adjustment device.