Primary-gear-gearing-down compact-type mid-motor

Abstract

The invention discloses a primary-gear-gearing-down compact-type mid-motor. The primary-gear-gearing-down compact-type mid-motor comprises a shell, a motor body, a clutch, a gear reducing mechanism, acenter shaft and a chain wheel, wherein the motor body comprises a stator, a rotor and a core shaft; the center shaft penetrates through shaft holes in the two ends of the shell, supporting and positioning are carried out through center shaft bearings arranged in the shell, and the core shaft and the center shaft are parallelly arranged; the primary-gear-gearing-down compact-type mid-motor is characterized in that the shell is formed by buckling and fixing a motor front cover and a motor back cover, the motor body is of an outer-rotor inner-stator structure, the gear reducing mechanism comprises a small gear fixed or integrally arranged on the core shaft and a large gear engaged with the small gear, an inner ring of the large gear and an outer ring of the clutch are fixed or integrally formed, an inner ring of the clutch is installed on the center shaft through a clutch bearing, and a chain-wheel positioning sleeve extending out of the shaft holes of the shell is integrally formed atthe front end of the inner ring of the clutch to fix the chain wheel. The motor structure is more compact, smaller in size and much less in part, and is particularly suitable for an electric bicycle with the small motor design power, and the production cost can be greatly saved.

Description

technical field [0001] The invention relates to a gear-reduced compact mid-mounted motor. Background technique [0002] The mid-mounted motor is the core power component of an electric bicycle. At present, the development of the mid-mounted motor in the industry is based on compact structure, small size, and large output torque. [0003] Existing mid-mounted motors usually have a parallel-expandable structure, and their composition usually includes a casing, a motor body, a gear reduction mechanism, a clutch, a central shaft and a crankshaft. The mandrel of the motor body is connected with the crankshaft sleeved on the central shaft or its positioning member through a gear reduction mechanism. At present, the gear reduction mechanism mainly adopts multi-stage gear transmission to replace the original planetary gear reduction mechanism with relatively complicated structure and many parts. The clutch is usually installed between a certain intermediate gear of the gear reduct...

AI Technical Summary

Problems solved by technology

[0005] 1) For some electric bicycles with relatively small motor design power, a higher reduction ratio is actually not needed, but the manufacturer has no choice but to use the above-mentioned multi-stage gear-driven mid-mounted motor. As we all know, The middle motor with multi-stage gear transmission, in addition to including many transmission parts such as the intermediate gear and its transmission shaft, the motor shell part often needs to design the motor middle cover between the rear cover and the front cover of the motor as the mounting bracket for the intermediate gear. Production costs are often high, which undoubtedly results in a waste of production resources

[0006] 2) Apply the existing multi-stage gear transmission mid-mounted motor to an electric bicycle with a small power motor. Because the internal multi-stage gear reduction mechanism occupies a large space, it is impossible to further effectively reduce and optimize the radial size of the motor, resulting in the overall motor The structure and volume are still not compact enough, which also brings inconvenience to the installation and positioning of the motor on the frame

[0007] 3) In order to increase the reduction ratio, the traditional mid-mounted motor often sets the motor body as the structure of the inner rotor and outer stator. The disadvantage is that the output torque of the motor is small

Of course, the current solution is to reprocess the ratchet sleeve to increase the number of ratchet teeth, but on the one hand, it is difficult to process, and on the other hand, the mold needs to be re-opened, and the existing ratchet sleeve will inevitably be scrapped, which is a waste for the enterprise.

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