GB189708337A - Improvements in Variable Ratio and Reversing Gearing. - Google Patents

Abstract

8337. Woolidge, W. April 1. Boring and drilling; tapping.-Variable ratio and reversing gearing for boring and tapping machines &c. The driving-shaft S carries two coned discs A, A', around which are placed a set of rollers C, the ends T, T' whereof are parts of cones adapted to roll upon the discs, i.e., their surfaces all run into one point S<2>. The roller ends T are embraced by the annular driven wheel R, which has its inner surface correspondingly coned. The bodies of the rollers are coned in the opposite direction to their ends, and so that their outer surfaces are parallel to the shaft. They are embraced by a ring B, which is adjustable in the direction of the length of the shaft by means of a rod 0 and hand-wheel P, or lever V. The latter may be actuated by an endless band J or by a link D, which may be coupled to a governor. When the ring B makes contact with the rollers at the point where the surface of the cones of the roller ends T, T' would intersect that of the cones C, no motion is transmitted to the wheel R. When the ring is on either side of this neutral position, the wheel is driven at a speed in a direction depending upon its distance from such position and upon which side thereof it is. A rod T<2>, passing through the rollers, is attached at each end to a loose ring F, F<1>. The wheel R may be a chain-wheel, and it may be drawn up in the direction of the arrow for pressing the rollers into contact by means of the adjusting-screw U. The cones, rollers, &c. may be partly toothed, and the ring B may likewise be provided with pins adapted to engage in holes in the rollers. The ring may be caused to move along the roller by slewing the latter to one side or the other ; this is effected by giving the disc A a slight rotation in relation to the disc A' by means of a sliding sleeve on the shaft provided with a projection entering a helical groove in the eye of the disc. By interposing springs between the projection and the recess in which it works, the action will be rendered automatic when the strain upon the gear becomes excessive. The arrangement shown may be duplicated upon the other side of the wheel R. Both the discs A, A' and the roller ends T, T' may be on one side of the cone C. In a modification, the cones C are reversed so that their inner surfaces are parallel to the shaft and the ring B is replaced by a disc on the end of a sleeve ; one set of the roller ends T' is then dispensed with.