| 摘要 |
PROBLEM TO BE SOLVED: To make the structure of a webbing take-up device simple which can permit the drawing of webbing to absorb energy. SOLUTION: Usually a spool 22 and a shaft 30 are rotated integrally and are free to make drawing-out and taking-up of a webbing 24. When a vehicle is decelerated rapidly, the rotation in the webbing drawing out direction of the shaft 30 is prevented. In the state where the rotation in the webbing drawing out direction of the shaft 30 is prevented, the webbing tensile force gives the spool 22 rotating force in the webbing drawing out direction to the shaft 30. In the shaft 30 and the spool 22, the spool 22 is rotated to the webbing drawing out direction to the shaft 30 by the rotating force so that a male screw 74 of a large diameter part of the shaft 30 cuts a female screw in an inner circumference 76 of a large diameter part of the spool 22, while the shaft 30 is moved to the shaft direction to the spool 22, causing the webbing 24 to be drawn out, thereby performing the absorption of energy. |
