| 摘要 |
632,305. Change-speed gear. SCINTILLA, Ltd. Nov. 13, 1946, No. 33712. Convention date, Aug. 5, 1944. [Class 80 (ii)] In a hub containing an epicyclic gear rendered operative or inoperative by a roller clutch actuated by centrifugal weights, the weights are pivotally mounted in a casing coupled to the internal ring of the roller clutch which forms the annulus of the epicyclic gear. A planet carrier 4 carries the driving sprocket 3 and is journalled on the fixed spindle 1, with which is rigid the sun gear 6. The carrier 4 is rigidly connected with the driving member 10 which is in one-way clutch connection 26 with the hub shell 16, and in similar connection in the opposite sense with a back pedalling brake 30 through a oneway clutch 27. Journalled on the member 10 and driven by a tongue 18 from the annulus 9 is a casing 12 supporting the pivots 14 of two fly-weights 13. The weights 13 are normally held inwards by springs 15 and so, through the projections 24 engaged by the slats 25 of the weights, the cage 23 for a jamming roller free-wheel 22 between the annulus 9 and the hub shell 16 is held in the declutched position. At a predetermined speed the weights move out against the springs and rotate the cage 23 to engage'the clutch 22 which drives the hub shell 16 at a higher speed and causes the clutch 26 to overrun. The weights 13 are pivoted as near the axis of the hub as practicable to ensure a substantially circumferential movement of the slots 25 which are cut 180 degrees from the pivots. |
