ENGAGING AND DISENGAGING DEVICE, SEAT BELT RETRACTOR, AND SEAT BELT ASSEMBLY

The present invention relates to an engagement and disengagement device, a seat belt retractor, and a seat belt assembly. An engagement and disengagement device used in a seat belt retractor includes a first rotating member and a second rotating member that are configured to be coaxial, and a transmission member disposed between the first rotating member and the second rotating member. The first rotating member defines an engagement portion on a radial inner surface thereof, and the distance from the engagement portion to an axis of rotation gradually increases in a first direction of rotation. The transmission member can rotate between an engagement position and a non-engagement position relative to the first rotating member. When the transmission member is at the engagement position, the transmission member engages with both the first rotating member and the second rotating member, such that the first rotating member, the second rotating member, and the transmission member can rotate together. When the transmission member is at the non-engagement position, the transmission member does not engage with the first rotating member and the second rotating member, such that the first rotating member and the second rotating member can freely rotate relative to each other.