| 摘要 |
<p>#CMT# #/CMT# The device has pedal shafts (34, 1) assembled on respective rolling bearings (35, 37), where the shaft (1) includes a primary multiplication pinion and a smooth cylindrical surface on which secondary pinions (5) are placed. A machined slot is provided on the surface and houses ratchets. A series of circular grooves houses an elastic return system i.e. open annular ring, of other ratchets. A series of openings houses pistons, balls or ratchet raising system. Another series of openings partially engage indexing balls, and large tertiary pinions are assembled on a free wheel. #CMT#USE : #/CMT# Device for changing speed in a gear box e.g. jaw clutch gear box and star wheel gear box, of a bicycle. #CMT#ADVANTAGE : #/CMT# The configuration of the device ensures constant alignment of a chain or a driving belt and permits protection of the gear box against water projections, mud, impacts and branches. The configuration of the device permits increasing of ratios without releasing an effort, and to change the speed even at a stop condition of a bicycle. The configuration of the device permits to change the speed, in a simultaneous manner and to eliminate the need of releasing an effort on pedals during a movement, for decreasing the ratios. The configuration of the device eliminates the need of derailleurs and frequent adjustments and readjustments due to cables. The device has reduced maintenance. The configuration of the device permits reduction of weight of the existing gear box, locking of pinions during changing of speed without blocking and without false dead points, and avoid engagement of a gear teeth and a jaw clutch of the existing box. The configuration of the device permits to avoid displacement and fragility of a star wheel and lateral engagement of the star wheel in furrows, and to limit overgear of the secondary pinions. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a schematic view of a speed changing device. 1, 34 : Pedal shafts 5 : Secondary pinions 35, 37 : Rolling bearings 40 : Tertiary shaft 41 : Chain pinion.</p> |
