JPH02171394A - Transmission for motor cycle - Google Patents

Abstract

PURPOSE:To contrive to actuate gear shifting in a small space in a simple manner by housing a gear shifting mechanism making use of a cone type rotor within a rear wheel hub, and thereby moving the gear shifting ring of it to the direction lowering the revolution speed of the hub while overcoming a spring. CONSTITUTION:The seat 26 of a gear shifting ring 1 within a rear wheel hub 10 is moved by actuating a gear shifting actuation device 20 so that the gear shifting ring 1 is moved on the conical surface of a cone type rotor 2 to the direction lowering revolution speeds while a coil spring is being overcome. Which causes a large diameter transmission wheel 4 to be reduced in rotation, which is connected with a rear axle 12 via an one-way clutch 16 and a sleeve 17. Thus, the degree of movement between the gear shifting ring 1 and the conical surface of the cone type rotor 2 is changed by the actuating degree of a gear shifting actuation cable 23 so that the large diameter transmission wheel 4 can be so changed that it is reduced in rotation. The footing force onto the pedal for uphill roads and the like can thereby be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to a transmission for a bicycle or a two-wheeled vehicle powered by an internal combustion engine with relatively low output.

Conventional technology: Many of the current two-wheeled vehicles use automatic transmissions.

a. In the case of bicycles: The mainstream is to change the chains on a series of tin rocket vehicles installed in multiple rows, and the number of stages of tin rocket vehicles installed gradually increases, making them expensive and have many parts. There is a tendency.

b. In the case of moped two-wheeled vehicles: Some use multi-gear transmissions and others use belt-type continuously variable transmissions, but the transmission occupies a large space, has many parts, and the transmission system The problem is that it is heavy.

In view of the above-mentioned circumstances, the present invention aims to develop a transmission for a two-wheeled vehicle that has a small number of parts, is easy to assemble and maintain, and is manufactured to be relatively lightweight.

Means for Solving the Problems: A two-wheeled vehicle transmission according to the present invention that solves the above problems has the following features:
A conical surface that frictionally engages in the transmission ring, a concave annular transmission surface that frictionally engages a small-diameter track ring fixed to the rear axle, and a large-diameter transmission surface that is frictionally engaged with a foot- or motor-driven large-diameter transmission wheel. A plurality of conical trochanters having mating flat transmission surfaces are housed in a sealed space in the hub of the rear wheel, one end of which is engaged with the hub of the rear wheel, and the other end of which is engaged with a speed change ring. A coil spring is provided that transmits the rotation of the conical rotor to the hub of the rear wheel, and the speed change ring is moved in a direction that resists the force exerted by this coil spring and reduces the rotational speed of the hub of the rear wheel. The present invention is characterized in that it is provided with a speed change operation device for controlling the speed change.

Effect: The transmission mechanism according to the present invention described above is disclosed in Japanese Patent Application No. 59-66237 (Japanese Unexamined Patent Publication No. 60-208675) filed by the applicant.
It is similar to the one in No. 3), and Figure 6 shows its main part.

In this figure, 1 is a speed change ring, 2 is a conical trochanter, and 3
is a conical surface, 4 is a large diameter transmission wheel, 5 is a small diameter raceway ring, 6
7 is a flat friction transmission surface, and 7 is a friction transmission surface with a concave cross section.

a: Effective radius of conical surface 3 for gear shifting ring 1 (2) Effective radius of flat friction transmission surface 6 for large diameter transmission wheel 4 C: Effective radius of transmission ring 1 d: Large diameter for flat friction transmission surface (B) Effective radius e of the transmission wheel 4: effective radius f of the friction transmission surface 7 with a concave cross-section with respect to the raceway ring 5: effective radius of the raceway ring 5 with respect to the friction transmission surface 7 with a concave cross-section, then rotational speed N2 of the speed change ring 1 The ratio N2/N of the rotational speed N1 of the large-diameter transmission wheel 4 is expressed by the following equation.

N2/N1=d(ec+fa)/c(ad+fb)--
filN2/N becomes 1 when the speed change ring 1 is approximately in the illustrated position and the condition a:b=c:a is satisfied. This can be easily confirmed by calculating by substituting the above equation 1ca==bc/d.

The effective radius a is a variable that can be changed by operating the speed change operating device, and N2/N gradually decreases as a decreases. a
If we consider the ultimate state where = Q, the above equation (1) becomes N2/N, = dec/c (ed + fb) = ae/(
ea+fb) = i/ (1+fb/de) fb/do #
1, so N2/N1″, 1/2. Practically, the point a = 0 cannot be used. Therefore, N2/N,
By appropriately selecting the constant a % f, the point set to +0.5 is set to be a point that is a little distance (for example, 6M) from the apex of the conical surface.

Embodiment: FIG. 1 is a longitudinal sectional side view showing an example of a transmission for a two-wheeled vehicle according to the present invention. In this figure, numeral 10 is a hub of a rear wheel, and inside it there are shown in FIG. A continuously variable transmission mechanism 11 is housed therein. 12 is the rear axle, 13.14 is the rear axle 1
The transmission of power to the fork supporting the fork 2 is carried out along the following path: tin rocket vehicle 15 → one-way clutch 16 → sleeve 17 → press force generator 18 → large diameter transmission wheel 4 → conical rotor 2. The speed change ring 1 is rotated.

19 is a coil spring interposed between the hub 10 and the speed change ring 1, and 20 is a speed change operation device that moves the speed change ring 1 in the axial direction. As shown in FIG. 2, the coil spring 19 has one end 21 engaged with the hub 10 and the other end 2.
2 is engaged with the speed change ring 1 and acts as a power transmission element that transmits the rotation of the speed change ring 1 to the hub 10. The coil spring 19 further acts as a return spring for the speed change ring 1 that is moved in the deceleration direction by the speed change operating device 20. The above-mentioned speed change operating device 20 is configured to include a manual or foot-operated operating cable 23, a bell crank 24, an interlocking rod 25, and a catch ring 26 for receiving the gear shift ring 1. When the gear ratio R=N2/N is pulled toward 1, the gear ratio R/G1 is moved in the direction of bringing the gear ratio R=N2/N closer to 1 (speed increasing direction). The above-mentioned movement of the speed change ring 1 by the speed change operation device 20 is performed on the condition that the state of frictional engagement of the speed change ring 1 with the conical rotor 2 is maintained.

During normal driving, the gear shift operating device 20 is operated and the gear shift operating device 20 is operated in a limp state (a state in which a:b=c:a is satisfied between the effective radii a, b, c, and 6 in Fig. 3, and Nz/N+ = 1). The shift operation device 20 is operated as appropriate when transitioning to traveling on a slope. In the case of a bicycle, the change of N2/N by the gear shift operating device 20 is made in consideration of the amount of pedal force required of the rider, and in the case of a motorized two-wheeled vehicle, it is made in consideration of the capacity of the motor. be exposed.

Effects of the invention: Bicycle transmissions are required to have an increased number of gears, resulting in an increase in the number of parts and an increase in price, but the present invention solves this problem and streamlines the supply of bicycle transmissions. This contributes to On the other hand, multi-stage gear reducers and belt-type continuously variable transmissions used as transmissions for moped motorcycles had drawbacks in terms of the amount of space required for installation, the view, and the number of parts. However, the present invention avoids these drawbacks.

Furthermore, the device according to the present invention is extremely easy to inspect and clean, and there is little chance of failure.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional side view showing one example of a transmission for two-wheeled vehicles according to the present invention, FIG. 2 is a partial view showing the installed state of a coil spring as a power transmission element in the transmission shown in FIG. 1, and FIG. The figure is an explanatory diagram of the gear ratio of the friction transmission system shown in FIG. 1. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A conical surface that is inscribed in and frictionally engaged with the speed change ring, an annular transmission surface with a concave cross section that frictionally engages with a small diameter raceway ring fixed to the latter shaft, and a large diameter transmission wheel driven by a foot or motor. A plurality of conical rotors each having a flat transmission surface that frictionally engages with the rear wheel are housed in a sealed space in the hub of the rear wheel, one end of which is engaged with the hub of the rear wheel, and the other end of which is connected to the transmission ring. A coil spring is provided which is engaged with the conical rotor and transmits the rotation of the conical rotor to the hub of the rear wheel. A transmission for a two-wheeled vehicle, characterized in that it is provided with a speed change operation device for moving the.