GB187065A - Improvements in or connected with artificial limbs - Google Patents

Abstract

187,065. Blatchford, C. A., Blatchford, C. D., and Blatchford, W. A. Aug. 6, 1921. Limbs, artificial.-In an artificial limb of the 'type wherein two members are hinged together and are capable of being positively locked in various angular positions relatively to each other, one member c carries an internally-toothed drum a rotatably mounted on a pin d carried by the other limb member e. The invention is described with reference to an artificial arm in which the pivot pin d is screwed into a square block h on which slides an externally-toothed disc g normally pressed into engagement with the toothed drum, to lock the limb, by one or more springs i. A cable or the like k attached to a bridge-piece l on the disc enables the latter to be disengaged, and the lower limb-member may then be angularly adjusted by means of a control-cable j lying in a peripheral groove b on the toothed drum. A pivoted spring-actuated pawl m holds the disc out of engagement if it be withdrawn sufficiently to enable the hooked end n of the pawl to pass through an opening o and engage the back of the disc. This pawl is automatically tripped by a projection p on the toothed-drum when the drum is rotated to a predetermined angular position. The lock may be released by hand by pressing a button z on one end of a pivoted lever x, the other end y of which engages the bridge-piece l on the locking disc; otherwise the locking is controlled through a strap v by raising or lowering the shoulder, and the lower member is rotated by rounding the shoulders, a back view of the harness is given in Fig. 5.