Inner speed changer of bicycle

Abstract

An internal speed changer of a bicycle is provided with a gear control mechanism and comprises a control assembly and a plurality of rod-like executing assemblies (9, 10); the control assembly comprises a control cam ring (4) sleeved on a wheel shaft (18) in a noncontact manner, and control protrusions (3) are arranged at the both ends of the control cam ring (4); the plurality of rod-like executing assemblies (9, 10) are controlled by the control assembly so as to control the action of various clutches within the internal speed changer; the rod-like executing assemblies (9, 10) are mounted on the wheel shaft (18) in an embedded manner, rendering the speed changer more simplified in structure and lighter in weight; with the contour of the control protrusions (3) matching the action of the rod-like executing assemblies (9, 10), the internal speed changer can be operated only by a bicycle thumb shifter, giving great easiness and convenience to gear operations; the internal speed changer is also applicable for different speed levels, thus the practicability of the internal speed changer is improved.

Description

technical field [0001] The invention relates to an internal transmission of a bicycle. Background technique [0002] Bicycle transmissions are divided into two categories: external transmissions and internal transmissions. The external transmission uses an open chain mechanism as the transmission system. The components of the transmission are exposed, which is easily disturbed by external forces, resulting in unstable shifting action, and generally has the disadvantage of short service life, and the noise is relatively large during the shifting process; the internal transmission uses a planetary gear mechanism as the main transmission body, and at the same time, the assembly is closed In the hub of the rear wheel axle of the bicycle, the above-mentioned defects of the external transmission can be overcome, and better transmission performance of the bicycle can be provided, which is becoming more and more popular in the production and application of bicycles. [0003] The ge...

AI Technical Summary

Problems solved by technology

[0002] Bicycle transmissions are divided into two categories: external transmissions and internal transmissions. The external transmission uses an open chain mechanism as the transmission system. The components of the transmission are exposed, which is easily disturbed by external forces, resulting in unstable shifting action, and generally has the disadvantage of short service life, and the noise is relatively large during the shifting process; the internal transmission uses a planetary gear mechanism as the main transmission body, and at the same time, the assembly is closed In the hub of the rear wheel axle of the bicycle, the above-mentioned defects of the external transmission can be overcome, and better transmission performance of the bicycle can be provided, which is becoming more and more popular in the production and application of bicycles

[0003] The gear position control mechanism of the bicycle's internal transmission is to achieve different transmission speed ratios by controlling the engagement or separation of the sun gear or the planetary carrier or the outer ring gear in the planetary gear mechanism. The clutch mechanism applied to the bicycle internal transmission is usually a pawl Type overrunning clutch, the traditional internal transmission separately controls the ratchet action of the clutch between the gears of the planetary gear mechanism to realize the speed change. Therefore, in the process of controlling the gear shift, it is necessary to set up multiple operating mechanisms to realize the operation, and the operation is complicated. At the same time, this transmission The control actuator is set on the rear wheel shaft of the bicycle. Generally, the more gears there are in the internal transmission, the more the control actuators are, which makes the structure of the internal transmission complex and cumbersome to operate.

On the other hand, the lightweight of bicycles is an important factor in the speed competition of bicycles. The existing gear position control mechanism of internal derailleurs obviously cannot adapt to the development of bicycles in this respect, which further restricts the promotion of internal derailleurs on bicycles.

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