17-10-2014, 04:21 PM
Abstracts: The one-way clutches now most commonly in use may be one of three types; the cam and roller type, the spring type, or the helical spring type. Although with long and intensive development these clutches have been made relatively satisfactory, they are comparatively expensive to manufacture and they possess certain inherent disadvantages. Among these disadvantages are, first, loads are transmitted through a line contact between a fairly small diameter roller or sprig and a race, resulting in very high local stresses. This then requires the use of premium steels which are carefully heat treated to withstand these conditions of operation. Second, extreme accuracy is required in the forming of the various pieces and this accuracy is difficult to obtain and increases the cost of the clutch. Finally, in the clutches of the prior art, wear occurs at the line contacts between the sprig and the race, or the cam and the roller, and this wear tends to quickly destroy the required accuracy in the clutches operation.