| 摘要 |
PURPOSE:To lessen torque hysteresis and bending stress by supporting the central portions of plural spiral springs on a core bar to cancel biased force at the time of torque load to reduce contact between the spiral springs. CONSTITUTION:A spiral spring 10 has a central portion 20a thereof mounted in a split groove of a core bar 20 and outer ends 10b, 10c which are respectively supported and fixed on support hooks 30a, 30b. Though at the time of torque load, force is worked in the arrow B and arrow C directions, the spiral spring 10 will not be biased in one direction, becaused such forces of two directions work in such a manner as to cancel each other. Accordingly, contact between the plates caused by a bias of the spiral spring 10 can be reduced to lessen torque hysteresis considerably. |
