Automatic speed-changing device

Abstract

The invention relates to the technical field of bicycles, in particular to an automatic speed-changing device. The automatic speed-changing device comprises a pull wire, a derailleur, a drive mechanism, a sensor and a controller, wherein one end of the pull wire is connected with the output end of the drive mechanism, and the other end of the pull wire is connected with the derailleur; the drive mechanism and the sensor are electrically connected with the controller respectively; the sensor is used for monitoring a movement frequency value of a pedal crank and sending the movement frequency value to the controller; the controller generates a movement instrument of a corresponding gear according to the movement frequency value and sends the movement instruction to the drive mechanism; the drive mechanism executes the movement instruction, and the derailleur is adjusted to be at an angle of the corresponding gear under drive of the pull wire. According to the automatic speed-changing device, the controller controls the drive mechanism, and the pull wire changes the angel of the derailleur, so that automatic bicycle speed changing can reach the best state.

Description

technical field [0001] The invention relates to the technical field of bicycles, in particular to an automatic transmission. Background technique [0002] The effect of the bicycle speed change system is exactly to change the speed of the vehicle by changing the cooperation of the chain and the gear discs of different front and rear sizes. The size of the front cog plate and the size of the rear cog plate determine how hard the bike spins the pedals. The larger the front cog and the smaller the rear, the harder it is to pedal. The smaller the front cog and the larger the rear, the easier it is to pedal. According to the ability of different riders, the speed of the bicycle can be adjusted by adjusting the size of the front and rear gear discs, or it can cope with different road sections and road conditions. [0003] figure 1 It is a structural schematic diagram of an existing speed change device; see figure 1 As shown, in the existing bicycle, the speed change method of...

AI Technical Summary

Problems solved by technology

[0005] First, the rider usually shifts gears based on experience. Untrained riders lack rationality in the selection of shift gears, and do not understand the interaction force of the derailleur including the front derailleur and the rear derailleur. It is easy to cause low pedaling efficiency, damage to the transmission device and sports injuries;

[0006] Second, the difference in quality of the shifting handle, cable, and derailleur and the technical experience of the technicians lead to cumbersome adjustment of the shifting device, and it is difficult to adjust to the best state, which will easily lead to accelerated wear of the chain and gear discs, unsmooth shifting and Faults such as gear jumping;

[0007] Third, the shifting handles and derailleurs of different brands and different gears are not compatible, resulting in high upgrade costs; for example, the shifting handle of 8th gear cannot work with the derailleur of 9th gear; replace the tower with more pieces In order to achieve the upgrade purpose of increasing gears, the corresponding shifting handle and derailleur must be replaced at the same time.

[0008] To sum up, the shifting of the existing transmission device depends on the technology and experience of personnel, which may easily cause problems such as low pedaling efficiency, damage to the transmission device, and personnel sports injuries.

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