Variable speed chain wheel structure for light load chain transmission and optimization method thereof

Abstract

The invention relates to the technical field of chain transmission, in particular to a variable speed chain wheel structure for light load chain transmission and an optimization method thereof. The variable speed chain wheel structure comprises at least one variable speed chain wheel group, the variable speed chain wheel group comprises a driving chain wheel and a driven chain wheel, and the driving chain wheel is provided with an upper chain avoiding system and a lower chain avoiding system. According to the variable speed chain wheel structure, it can be effectively guaranteed that fast and smooth switching between different speed ratios is achieved under the state that chain loads and transmission are not interrupted, for example, when larger torque is needed, the variable speed chain wheel structure is switched to the small speed ratio at any time, and when higher speed is needed, the variable speed chain wheel structure is switched to the large speed ratio at any time. The structure is high in structural compatibility, and supports mainstream bicycles, spinning bikes and sports equipment needing rapid speed ratio switching in the market; abrasion and scraping between parts are reduced, the mute performance is good, and the service life is long. In addition, the invention further provides an optimization method of the variable speed chain wheel structure, more optimized structural design of the chain wheel structure can be achieved, and the design method is novel and higher in practicability.

Description

technical field [0001] The invention relates to the technical field of chain transmission, in particular to a variable speed sprocket structure for light load chain transmission and an optimization method thereof. Background technique [0002] Chain transmission is the main form of the transmission mechanism in the riding device. It has the advantages of light structure, easy maintenance, stable transmission, and small impact and vibration. With the development of bicycle chain transmission technology, the application advantages of variable speed chain transmission bicycles in complex terrain occasions have been generally recognized. For example, mountain bikes and road bicycles all use sprocket combinations with different transmission ratios to meet different applications. [0003] The speed-changing bicycles currently on the market usually have at least two sprockets and a chain with different numbers of teeth in the transmission mechanism, wherein the chain is encircled a...

AI Technical Summary

Problems solved by technology

During the load operation, the sprocket and the chain are likely to interfere and collide due to the poor precision of the speed change action, resulting in a large amount of wear of the sprocket, low service life and high operating noise.

In the prior art, the chain avoidance groove is set at the appropriate position of the sprocket teeth, and the auxiliary chain is effectively positioned and guided when moving between the sprockets. However, due to the imperfect design of the chain avoidance, there are usually chain Movement failure, low speed shifting efficiency, poor accuracy, and loud noise

At present, the common problems of chain avoidance design in the prior art are as follows: (1) The upper chain avoidance design is only for a single speed change chain, for example: 10 cranksets can only be compatible with 10 chains, 11 speeds and 12 speeds cannot be used, and the applicability is poor; (2) If it is used in a complex environment, such as in rainy or snowy days, when the chain sticks to a small amount of soil, sand, or freezes, the design position of the avoidance space and the fault tolerance rate are insufficient, resulting in a significant drop in shifting efficiency, which may be caused by insufficient shifting. Injuries were caused in a timely manner; (3) due to the imperfect design of the speed change and slope connection, the chain could not be fitted in time and accurately when the chain was going up and down, causing the rider to fall due to stepping into the air; (4) due to the imperfect design of the chain avoidance, As a result, the speed change process cannot be completed in time and accurately, and the tooth plate is worn out in advance, etc.

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