Abstract: A webbing take-up device includes a spool and a spiral spring that biases the spool in a take-up direction and a motor provided with an output shaft. The webbing take-up device further includes a first clutch that transmits forward direction rotation of the output shaft to the spool, rotating the spool in the take-up direction. The webbing take-up device further includes a second clutch including: weights that are rotated by the output shaft and that open out under their own centrifugal force; a connection-disconnection mechanism that receives force from the weights opening out and connects so as to enable rotation of the output shaft to be transmitted to the spool; and projection portions serving as load limiting portions that limit the load imparted to the connection-disconnection mechanism so as not to become a specific value or greater.

Abstract: An engaging member supporting structure having a rotating body being connected to a spool, transmitting rotation to the spool and having rotation from the spool transmitted thereto; a support body provided coaxially with the rotating body; an engaging member provided at the support body and rotating in one direction to engage with the rotating body; a shaft potion formed at one of the support body or the engaging member; and a bearing portion formed at the other of the support body or the engaging member in such a manner that the shaft portion is inserted therein, whereby the engaging member is rotatably provided at the support body, wherein, in a state in which the engaging member engages with the rotating body, a clearance is formed between an outer peripheral surface of the shaft portion and a portion of an inner peripheral surface of the bearing portion.

Abstract: A webbing winding device includes a clutch mechanism interposed between a spool and an output shaft of a motor and has a simple structure and high operability. In an interference piece that has an interference portion interfering with a connection pawl when an input gear of a clutch is rotated in the winding direction, a base portion is disposed between an outer retaining ring and an inner retaining ring formed at a gear box, and the base portion comes into press contact with an inner peripheral portion of the outer retaining ring and an outer peripheral portion of the inner retaining ring. The interference portion keeps interfering with the connection pawl until a pressing force more than a maximum static frictional force generated between the inner peripheral portion of the outer retaining ring and the outer peripheral portion of the inner retaining ring, and the base portion is applied to the interference portion, thereby rotating the connection pawl.

Abstract: An engaging member supporting structure having a rotating body being connected to a spool, transmitting rotation to the spool and having rotation from the spool transmitted thereto; a support body provided coaxially with the rotating body; an engaging member provided at the support body and rotating in one direction to engage with the rotating body; a shaft potion formed at one of the support body or the engaging member; and a bearing portion formed at the other of the support body or the engaging member in such a manner that the shaft portion is inserted therein, whereby the engaging member is rotatably provided at the support body, wherein, in a state in which the engaging member engages with the rotating body, a clearance is formed between an outer peripheral surface of the shaft portion and a portion of an inner peripheral surface of the bearing portion.

Abstract: A webbing winding device includes a clutch mechanism interposed between a spool and an output shaft of a motor and has a simple structure and high operability. In an interference piece that has an interference portion interfering with a connection pawl when an input gear of a clutch is rotated in the winding direction, a base portion is disposed between an outer retaining ring and an inner retaining ring formed at a gear box, and the base portion comes into press contact with an inner peripheral portion of the outer retaining ring and an outer peripheral portion of the inner retaining ring. The interference portion keeps interfering with the connection pawl until a pressing force more than a maximum static frictional force generated between the inner peripheral portion of the outer retaining ring and the outer peripheral portion of the inner retaining ring, and the base portion is applied to the interference portion, thereby rotating the connection pawl.