GB872911A - Improvements in or relating to manually operated wrenches - Google Patents

Abstract

872,911. Wrenches. HARE, T. G. April 13, 1960, No. 13184/60. Class 61. A reversible ratchet wrench comprises a rotatable member 14 journalled in a cylindrical opening 13 in the head 12, the opening 13 having a wedge shaped cavity 16 in which a wedge shaped pawl 19 is spring biased to move in a radial direction towards the member 14 and has an arcuate saw of teeth along one edge engageable with ratchet teeth 15 on the member 14, the pawl being shiftable in the cavity circumferentially of the rotatable member 14 in opposite directions as limited by engagement of the side walls of the pawl by the side walls of the cavity 16. As shown, a coil spring 26 is positioned between the pawl 19 and a pin 23 rotatably mounted in the body of the wrench. The pin has a handle 35 by which it may be rotated from a first to a second position, to shift the axis of the spring and with it the pawl, between one side and the other of a line extending between the pin and the axis of rotation of the rotatable member. The pin is locked in one or other position by a spring pressed ball 32 and detent means. The cylindrical member 14 has an axial projection 50 which provides a disconnectable connection for socket wrenches or the like. A cap 39 having a tab 40, and an annular wall 44 having a tab 45 are sealed to the head to provide oil seals. In a modification, Figs. 9-12 (not shown), the movement of the pawl is guided by an upwardly extending pin attached to the foremost end of the spring, the pin being adapted to move in a V-shaped slot in the body. In another modification, Figs. 13, 14 (not shown), an endless coil spring is provided of greater outer diameter than that of a circumferential groove in the circular rotatable member in which it is positioned. A portion of the spring extending between the pawl and the cavity moves the pawl radially outwards during the shifting of the pawl from one position to the other.