Patent ID: 7290730
Filing Date: 2007-11-06
Classification: B60R

Abstract:
1. A webbing retractor used in a seat belt device of a vehicle, the webbing retractor comprising: a frame; a webbing; a sensor for sensing an emergency condition of said vehicle; a spool to which one end of the webbing is fixed, and which is rotatably mounted at both ends to said frame and can rotate in a webbing take-up direction and in a webbing pull-out direction which is opposite to the webbing take-up direction; a torsion shaft, a first end of which is fixed to one axial direction end side of the spool; a pretensioner connected to a second end of the torsion shaft by way of a coupling mechanism, and that operates to wind said webbing in a webbing take up direction in response to a preselected emergency condition, and a lock mechanism that is connected to said sensor and that includes a moveable lock plate operating to releasably lock rotational movement of said torsion bar relative to said frame during either said sensed emergency condition or said preselected emergency condition that operates said pretensioner, wherein said lock mechanism releasably locks only the second end of the torsion shaft such that the first end of the torsion shaft remains unlocked and rotation of the spool in the webbing pull-out direction is restricted only at the second end of the torsion shaft, and wherein all of the lock mechanism is provided only at a side of the spool where the pretensioner is provided, and wherein said lock mechanism is mechanically independent from said coupling mechanism and said spool.