To provide a power transmission mechanism to facilitate mounting and demounting on and from one rotary body through simple constitution, to improve workability during mounting and demounting, and reduce a fear of inadvertent movement of the rotary body during assembly.
A spline shaft 75 is formed at the end part of a second rotary body 26 on the driven apparatus side. A twist coil spring 80 is prewound on the outer peripheral surface of a cylindrical intervening member 76 in the inner peripheral surface on which a spline groove 77 is formed. The intervening member 76 is fitted in the end part of the second rotary body 26 and the intervening member 76 and the second rotary body 26 are securely interjoined by a lock bolt 78. Rotation of the twist coil spring 80 is stopped by a coupling plate 70 rotated integrally with a pulley 65.
BAN TAKASHI
YUSA KOJI
NHK SPRING CO LTD