Mechanical power transmission method and means

The method of making a mechanical transmission of the type having means defining a helix-like race, an input shaft, an output shaft, and one or more gears rotatively mounted to transmit rotary motion between the two shafts comprising the steps of forming each gear with a circular array of teeth engaged in said one or more races and which are

• A. stiff in the circumferential directions around the tooth array, but
• B. resilienty displaceable in planes which include the rotary axis of the gear, and
• C. selecting said resiliency so that when one of said shafts is rotated and the other of said shafts is under a torque load, the transmission has an intrinsic elasticity tailored to the manufacturing tolerances of its internal parts and the extrinsic characteristics of the torque load so that the transmission load is shared substantially equally among all of the engaging teeth in each gear.

The method of making a mechanical transmission of the type including a helix-like race having an axis of rotation a support member extending along the axis, at least one rotary bearing unit axially fixed to the support member and with its periphery positioned in rolling engagement with the race and a gear for rotating each bearing unit about said axis of rotation, comprising the steps of forming each bearing unit with a circular array of independent teeth each of which is

• A. stiff in the circumferential directions around the periphery of the unit, but
• B. relatively elastic in the planes which include said axis of rotation so that each tooth can be resiliently deflected in a said plane independently of the other teeth.

The method of making a mechanical transmission of the type including one or more helix-like races defining a plurality of race convolutions having a common axis of rotation, a support member extending along said axis, at least one planet gear axially fixed to the support member with its teeth positioned in rolling engagement with the race convolutions and a worm for rotating said gear about said axis so that the gear revolves about the worm axis comprising the steps of varying the number of race convolutions or worm threads in a manner which need not be a multiple of the number of teeth on the planet gear for each revolution of the planet gear about the worm axis, while varying the wall thickness between the race convolutions without changing the race, worm or planet gear diameters.