GB508461A - Improvements in or relating to motor-propelled bicycles - Google Patents

Abstract

508,461. Motor-cycle driving-gear; back-pedalling brakes. FICHTEL & SACHS AKT.-GES. Dec. 28, 1938, No. 37659. Convention date, Dec. 29, 1937. [Classes 79 (ii), 79 (iii) and 136 (i)] [Also in Group XXVII] A power unit for a bicycle has the pedal shaft 23 at the rear of the unit and below the engine shaft S, this pedal shaft being connected to the engine shaft by a one-way clutch 25, a lay shaft, and a disconnectible clutch, and the rear wheel of the cycle being driven by a sprocketwheel 15 mounted on a lay shaft 14 arranged between the engine and pedal shafts S, 23 and above the level of the pedal shaft. Thus, the driving chain 16 from the sprocket 15 to the rear wheel (not shown) is not interfered with by the pedal shaft. When the pedal shaft is rotated forwardly, it drives through the oneway clutch 25 either the rear wheel or the engine (for starting) at will, or both ; on backpedalling, the pedal shaft acts through a reverse one-way clutch 26 and gears 24, 27 on a shaft 28 having an arm 29 connected to a brake on the rear wheel. The engine shaft S is connected by a chain 7 to a sprocket 8 connected by a disc clutch 9a to a shaft 9 which drives the lay shaft 14 through two-speed gear comprising gears 11, 12 integral with the shaft 9, meshing gears 13, 17 loose on the shaft 14, and a double sliding clutch 30 splined on shaft 14. Thus, the engine can drive the sprocket 15 at either of two speeds. The pedal shaft 23 can also drive the sprocket 15 at either of two speeds : (1) directly through the gear train 22, 21, 20, 18, when clutch 30 connects the double gear 17, 18 to the shaft 14, and (2) indirectly through the shaft 9 when clutch 30 engages the gear 13. For starting the engine, the pedal shaft drives the shaft 9 through the one-way clutch 25 and the gear train 22, 21, 20, 18, 17, 12, the clutch 9a being engaged to drive the engine through the chain 7.