GB711309A - Improvements in or relating to socket wrenches and box spanners - Google Patents

Abstract

711,309. Spanners. FREEMAN, G. L. March 24, 1953 [March 24, 1952], No. 7464/52. Class 61 An adjustable box spanner comprises a tubular body having at one or both ends two or more jaws radially movable inwards towards the axis of the body by one or more longitudinally movable wedging members, separate springs bearing against each of the jaws to urge them outwardly.. As shown, a pair of jaws 12 slidable towards and away from each other in a housing 11 at the upper end of a body 10 of hexagonal section are grooved to receive inwardly projecting tongues 14. The jaws are pressed apart by leaf springs 15 which extend downwardly inside the body and are pressed apart by a helical spring 19. The lower ends of the springs are forked to straddle the bent over ends 16 of rods 17 which operate wedging members 21 disposed between the outer wall of the housing 11 and the sloping faces of the jaws. The legs 24 of the wedging members are secured to the ends 16 of the rods which extend through longitudinal slots in the body 10 The rods 17 are secured to a threaded collar 29 axially movable on the body 10. A cap 31 secured to the end of the body is provided with a square socket 32 in which a ratchet handle or bent lever may be inserted. In a modification a top plate is provided over the jaw housing. In another modification a spanner has sets of jaws at both ends which are operated by a single collar which when rotated causes one set of jaws to close and the other to open. In another modification, instead of a threaded collar, helical slots may be,provided to receive the ends of the operating rods.