GB190117153A - A New or Improved Multiple Speed Gear, applicable to Motor Vehicles, Cycles, Steam Engine Governors, and Chain Driven Mechanism generally. - Google Patents

Abstract

17,153. Wanabrough, W. D. Aug. 27. Chain-wheels.-Relates to an expanding chainwheel for variable-speed gearing in motor vehicles and cycles, for driving steam engine governors &c. of the kind described in Specification No. 12,561, A.D. 1901. A flexible chain ring a is mounted on a pair of discs h, i by means of pins which pass through lugs e and through slots in the discs. The slots are so shaped that the rotation of one disc in relation to the other causes the inward or outward movement of the pins in the manner required to retain the circular form of the ring. The gap between the ends of the ring when expanded is bridged by a strip b, pivoted to one end and adapted to slide under the other ; this piece has radial wings j provided with guide-pins to engage in slots in the discs. The disc i is rotated upon the disc h by means of a toothed segment, formed thereon, which gears with a pinion k<1>, mounted upon a stud on the disc h and formed in one piece with a star-wheel k<2>. The star-wheel is turned one way or the other, according as the diameter of the wheel is to be increased or diminished, by allowing one or other of two spring plungers p<2>, p<3>, mounted in the frame, to advance and bring a pin on its extremity into position for the star-wheel to engage it as it moves round, after another pin placed near it on the same plunger has lifted a pivoted locking-plate l, m. This plate again locks the disc after the star-wheel has been moved. To prevent this device from continuing to act after the chainwheel is fully expanded or contracted, the plungers are pushed in by an inclined flange t and a wing q<1> on the lever q respectively.