GB1265726A - - Google Patents

Abstract

1,265,726. Safety harness retraction device. JIM ROBBINS SEAT BELT CO. 2 April, 1969 [29 April, 1968], No. 17137/69. Heading A3V. A seat belt retracting device comprises a support 12, Fig. 1, a spring loaded reel, a locking pawl 70, Fig. 3, for preventing the reel rotating in an unwind direction, and a disabling cam follower 60 for disengaging the locking pawl 70 upon rotation of the reel through a predetermined angular distance in the winding direction. The belt 41 is stitched around a tube 36, Fig. 5, and clipped thereto by a member 42; the tube is rotatably mounted on plastics bushes 30, 32, the former being keyed to a non-rotatable inner tube 24 and bolt 18 and being connected by a spring 35 to the bush 32 which is keyed to the tube 36. Ratchets 43, 44 are keyed at 44' to the ends of the belt clip 42, and the reel assembly mounted on the support by bolt 18, with spring 35 biasing the belt to a wound up position. A grooved cam 52 is mounted by lugs 54 on one ratchet 43, and operates a folpin 62, Fig. 3, mounted on the follower 60 having a slotted portion 64 around the bolt 18, so that rotation of the reel translates the follower 60 transverse the bolt. An over-centre spring 65 is mounted on the support at 66 and connected to the follower at 68. Cam 52 has inner and outer circular grooves 56 and 55, centered on the bolt 18 and connected by a spiral groove 58. A pawl 70 is pivoted to the support at 72, and has a pin 78 slidably engaging a slot 80 in follower 60; when the follower is in its left side position shown in Fig. 3, the pawl is held away from ratchet teeth 48 by pin 78, and the reel may be unwound partially or wholly so that a wearer may buckle the belt. The follower 60 moves to the right, Fig. 4 (not shown), during unwinding. When the follower is free from pawl 70, a time delay dash pot 81, which is compressed by a member (75) riveted (at 76) to pawl 70 when the latter is in the position shown in Fig. 3, slowly expands as air enters it through a pin hole and moves pawl 70 into engagement with teeth 48 on ratchets 43. The reel is thus locked against unwinding shortly after the belt is buckled. The spiral groove 58 is formed so that when the reel rotates through a predetermined angle in the wind direction, as on unbuckling the belt, the follower 60 operates on pin 78 and disengages pawl 70. This angle is chosen such that the reel may take up slack in the buckled belt without freeing the pawl from the ratchet, but is also chosen so that the pawl is disengaged without completely winding in the belt.