Multiple speed hub for a bicycle with centrifugally controlled speed change and override mechanism actuated by back pedaling
AssigneeFichtel & Sachs AG
InventorHans-Joachim Schwerdhofer
Life of this patent
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Abstract
Two transmission members of a planetary gear transmission in a hub of a driven vehicle wheel are driven simultaneously at different speeds in a forward or backward direction. Driven forward movement of the slower transmission member is transmitted to the hub shell by an overrunning clutch. A second clutch connects the other transmission member to the hub shell when operated by a centrifugal governor at a certain rotary speed. A control device responds to backward rotation of the transmission members, as by back-pedaling, for overriding the governor and for operating the second clutch independently of the rotary speed.
Claims18
A two-speed gear hub for bicycles and the like comprising:
- (a) a hub axle;
- (b) a hub sleeve rotatably mounted on said hub axle;
- (c) a planetary gear transmission in said hub sleeve including first and second transmission members operatively connected for simultaneous rotation about said axle at different speeds;
- (d) drive means for rotating said members in a forward direction and in a backward direction;
- (e) an overrunning clutch operatively interposed between said first transmission member and said hub sleeve for transmitting torque from said first member to said hub sleeve when said first member is rotated in said forward direction;
- (f) a pawl-and-ratchet clutch operatively interposed between said second transmission member and said hub sleeve and operable for transmitting torque from said second member to said hub sleeve when said second member is rotated in said forward direction;
- (g) a flyweight switch responsive to the rotary speed of one of said first and second transmission members for operating said pawl-and-ratchet clutch;
- and
- (h) control means responsive to backward rotation of said drive means and operating to be alternatingly switched between two operating positions for overriding said flyweight switch and for permitting engagement of said pawl-and-ratchet clutch in one of said operative positions and for preventing said engagement when in the other of said operative positions.
Dependencies are inferred from the claim text.