Patent ID: 6516908
Filing Date: 2003-02-11
Classification: B62M

Abstract:
A transmission for an electric bicycle, the transmission comprising:a housing (10) being composed of a first semi-housing (101) and a second semi-housing (102) symmetrically assembled together; a motor (20) having an output axle (21) extending into the housing (10), and a driving gear (22) secured on the output axle (21) and engaged with an idler (23); a crank axle (30) extending through the housing (10), the crank axle (30) having a stepped sleeve (32) rotatably provided thereon, a driven gear (34) provided on the stepped sleeve (32) and engaged with the idler (23), a first non-return means (35) assembled between the stepped sleeve (32) and the driven gear (34), and a second non-return means (36) assembled between the stepped sleeve (32) and the crank axle (30); a chain wheel (60) secured at a first end of the stepped sleeve (32); a seat (41) for the crank axle (30) extending therethrough, the seat (41) having a first gear (46) rotatably provided on the crank axle (30) and having a first end secured in the second non-return means (36), a second gear (47) secured on the crank axle (30), a duplicate gear (48) being composed of a third gear (481) engaged with the first gear (46) and a fourth gear (482) engaged with the second gear (47), and a nose (50) provided on an outer surface of the seat (41); and a force sensor (55) assembled on an inner wall of the housing (10) and corresponding to the nose (50).