| 摘要 |
1,032,098. [Taking up slack in fexible elements. E. H. REPLOGLE. Sept. 10, 1964 [Sept. 12, 1963], No. 37173/64. Heading B8B. [Also in Division A3] A retractable safety belt comprises automatic means rendered operative by partial retraction of the strap from a protracted position to prevent the strap from being further protracted. The strap 31 is wound on the shaft 57 of a spring reel 49 which supports a ratchet-wheel 79 which co-operates with a braking pawl 80 pivoting with shaft 82 and spring urged to engage the ratchet-wheel and kept out of engagement both by a finger 84 pivoted to an arm 83 and frictionally engaging a drum 90 on the shaft 57 and by a sensor arm 85 which contacts the surface of the strap. Both the arm 83 and sensor arm 85 pivot with the shaft 82. After the strap has been withdrawn, which renders the sensor arm 85 inoperative, and the buckle fastened, the reel is allowed to rotate to retract the strap to adjust the length to the girth of the body. During this retraction the finger 84 moves upwardly on the drum 90 and frees the shaft 82 to rotate the pawl 80 into braking engagement with the ratchet-wheel 79 under the action of the spring 92 preventing further withdrawal of the strap. When the buckle is unfastened the reel spring retracts the strap which causes the sensor arm 85 to rotate the shaft 82 bringing the finger 84 to its initial position abutting the drum 90. In another embodiment, the ratchet is linear depending from the top of the channel member 110, Fig. 13, and the strap 106, wound on a spool 129, is secured to a pawl 131 movable along the channel member and urged into engagement with the ratchet teeth by an elastic cord 152. The pawl is held out of engagement during withdrawal of the strap by two fingers 160 pivoting at one end of the pawl and spring urged to engage the upper surface of the channel member. During retraction the fingers 160 pivot in a clockwise direction to allow the pawl to engage the ratchet teeth and prevent further withdrawal of the strap. In an alternative form, the strap has to be withdrawn to the fullest extent before the pawl becomes operative. The fingers project into slots provided at the ends of the channel member. One slot prevents the pawl becoming operative and the other slot adjacent the spool allows the fingers to pivot so that during subsequent retraction of the strap the pawl engages the ratchet teeth to lock the spool against further withdrawal. |
