REGELBARES GETRIEBE.

摘要

The invention provides a variable ratio transmission unit including at least one first transmission element (10, 70, 72) mounted for rotation about a first axis (Y-Y), and at least one second transmission element (18; 68) in contact with the first element and mounted for rotation about a second axis (X-X). The first and second axes define a predetermined angle with each other. The first transmission element is generally disc shaped, with a profiled contact face (14) on one major surface thereof, and the second transmission element is generally cylindrical, with a complementally profiled contact face (16) on its periphery. The second element is slidable axially along the second axis to vary the distance between the point of contact (c) of the elements and the first axis, to vary the effective transmission ratio. The first and second elements are so profiled that the common tangent at the point of contact between the elements passes through the point of intersection of the first and second axes irrespective of the axial position of the second element, and relative movement between the elements is substantially rolling movement. The transmission unit finds application in a vehicle transmission, in which a pair of the units are combined with an auxiliary gearbox to provide a steplessly variable friction drive transmission.