Kabushiki Kaisha Tokai Rika Denki Seisakusho

Sumikazu Sasaki

Seiji Hori

Yasuho Kitazawa

Kenji Matsui

Keiichi Kato

Naohiro Tsukiyama

A notched ring rotates together with a spool and opposes a disk of a locking shaft portion. A substantially semicircular engaging projection is formed on an opposing surface of the notched ring in the peripheral direction thereof. An engaging concave portion is formed at the disk so as to correspond to the engaging projection. When the spool is rotated in the withdrawing direction of a webbing and the opposing surface of the notched ring abuts the disk, the engaging projection enters and engages the engaging concave portion without clearance therebetween. Accordingly, even if rotating force is further applied to the spool in the withdrawing direction of the webbing, movement of the notched ring in the outer peripheral direction is prevented, and a state in which the rotation of the spool is restricted is maintained.

Device for restriction an amount of rotation and webbing retractor

A webbing retractor includes a spool around which a webbing is wound in such a manner as to be capable of being pulled out; an energy absorbing member which is deformed by the spool when a rotating force acting in a pulling-out direction of the webbing is applied to the spool at the time of a sudden deceleration of a vehicle, so as to prevent an increase in a tensile force of the webbing; a pretensioner which is connected to the spool when a deceleration of a predetermined value or more is applied, so as to rotate the spool in a taking-up direction of the webbing; and a canceling portion disposed between the spool and the pretensioner so as to cancel the stopping of rotation in a paying-out direction of the webbing by the pretensioner after operation of the pretensioner. Accordingly, after the operation of the pretensioner, the rotation of the spool in the pulling-out direction of the webbing is not restricted, and the energy absorption by the energy absorbing member is not restricted.

Webbing retractor

A webbing retractor comprises a spool around which a webbing capable of being unwound therefrom is wound; a pretensioner for rotating said spool in a webbing winding direction when a deceleration of a predetermined value or more is applied during a sudden deceleration of a vehicle; an energy absorbing member put in a coupled state with said spool, rotated integrally with said spool and deformed by said spool to prevent an increase in tension of the webbing when rotational force in a webbing unwinding direction acts upon said spool after said spool has been rotated in said webbing winding direction by said pretensioner; and a cancelling portion applied with the rotational force in said webbing unwinding direction via said energy absorbing member when the energy absorbing member is deformed by the rotational force in said webbing unwinding direction, for cancelling the state in which rotation of said spool in the webbing unwinding direction is stopped by said pretensioner. Therefore, after the spool is rotated in the webbing winding direction by the pretensioner, the spool is rotatable in the webbing unwinding direction.

There is provided a webbing take-up device in which a load required to rotate a spool in a webbing drawing direction with reference to a shaft is stabilized in the process of rotating the spool, a stable load can be achieved with small deformation, and miniaturization can be achieved. In an ordinary state, an EA plate keeps its original shape, and the shaft and spool are rotated together with each other. When the shaft is prevented from being rotated in the webbing drawing direction in vehicle sudden deceleration, the EA plate is plastically deformed by a webbing drawing force, and the EA plate is pushed in an internal-angle portion of the spool with rotation of the spool in the webbing drawing direction with reference to the shaft. The EA plate is bent by a U-shaped portion and then wound around the outer periphery of the shaft. The other end portion of the EA plate is pushed into the internal-angle portion at a winding start end portion of the EA plate around the shaft to prevent the subsequential rotation of the spool in the webbing drawing direction with reference to the shaft. Thus, when the webbing is prevented from being drawn, the webbing is drawn by a predetermined length, and energy absorption can be achieved.

Growing community of inventors

Aichi-ken, Japan

Sumikazu Sasaki