TENSION ADJUSTMENT DEVICE AND METHOD FOR ASSEMBLING TENSION ADJUSTMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a tension adjustment device which performs a superior control over a force applied by a spring without being dependent upon a conical sleeve and has a single spring used for applying torque to one component element of the device and generating attenuation force.SOLUTION: A tension adjustment device 2 comprises: a reception housing 4; a lever arm 6 fixed to the reception housing and rotatable around a first rotating axis X4 with respect to the reception housing; a pulley 8 fixed to the lever arm and rotatable around a second rotating axis X6 in parallel with the first rotating axis with respect to the lever arm; and a spring 14 fixed between the reception housing and the lever arm and constituted to apply torque for use in rotating the lever arm around the first rotating axis. The reception housing and the lever arm are engaged in thread with each other around the first rotating axis. The spring applies an attenuation force E14 of axial direction in parallel with the first axis to cooperating threads 422 and 642 each of which is provided on the reception housing and the lever arm, respectively.