GB612496A - Improvement in variable speed device - Google Patents

Abstract

612,496. Variable-speed gear. THURSTON, A. P. (Ford Instrument Co., Inc.). July 10, 1946, No. 20610. [Class 80 (ii)] A variable-speed gear, which may be used as a mechanical integrator, comprises a sphere 20 driven by a roller 14 at a controlled rate and steered by a roller 35 mounted for orientation about an axis passing through the centre of the sphere and the point of contact of the roller 35, confining rollers 21 engage the sphere in a diametral plane and are mounted on an output member 22 for rotation about an axis normal to the diametral plane. A motor 10 drives the sphere 20 through the gears 11, 12 and the driving roller 14, the sphere 20 being held by confining rollers 21 mounted on a cage 22 which is journalled in the bearings 24 for rotation about the axis passing through the centre of the sphere and the point of contact of the roller 14. The steering roller 35 is mounted on a shaft 36 in bracket 38, the latter being arranged for rotation about a pin 39 whose axis lies on a line joining the centre of the sphere and the point of contact of the roller 35. Adjustment of the rotation about this axis is effected by an arm 58 rigid with the bracket 38 and having a slot 60 engaged by a roller 61 on a slide 62 movable transversely by a rack and pinion 70, 71, movement of the slide tilting the steering roller 35 and so increasing or decreasing the component of rotation of the sphere received by the confining rollers 21 on the output member. The greater the angle B the less will be the relative speeds of the roller 14 and the cage 22. In a modification, the relative positions of the steering and driving rollers are interchanged.