CLUTCH DEVICE

An engagement and disengagement device used in a seat belt retractor includes: a first rotating member (10), capable of being driven to rotate about a rotation axis thereof; a second rotating member (20), provided coaxially with the first rotating member (10), and connected to a reel of the seat belt retractor in an anti-torsion manner; and a transmission member (30), provided between the first rotating member (10) and the second rotating member (20). The first rotating member (10) is capable of transmitting, in a first rotation direction (C1), torque to the second rotating member (20) by means of the transmission member (30). The transmission member (30) includes a holder (31) and a transmission element (32) provided in the holder (31). Afirst elastic component (33) is used to elastically hold the transmission element (32) by radially exerting, on the transmission element (32), a force that enables the transmission element to be located away from the first rotating member (10) or the second rotating member (20), and the first elastic component (33) is integrated on the holder (31).