| 摘要 |
PURPOSE:To facilitate the releasing of a lock-up condition, by disposing a clutch mechanism between a lock means and a webbing wind-up shaft, and by providing a means for holding the driven side of the clutch mechanism in its lock condition. CONSTITUTION:Upon wind-up of a webbing W, when the wind-up rotation of a wind-up shaft 2 is abruptly stopped, a lock piece 7 meshes with ratchet teeth 11a formed in a ratch cup 11 due to the inertia of an inertia member 9 to establish a lock-up condition. In this condition, it the webbing W is to be forcedly pulled out, gaps between layers of the webbing W may be eliminated, and therefore, the webbing W may be pulled out by a slight amount. The wind-up may be made by an amount corresponding to the slight amount of the webbing W pulled out, and therefore, the shaft 2 is rotated counterclockwise, correspondingly. However, the ratch cup 11 is urged clockwise by means of a toggle spring 16, and therefore, it does not rotate in association with the rotation of the shaft. Therefore, the lock piece 7 and the teeth 11a are disengaged from each other to release the lock-up condition. |
