Patent GB-145646-A (GB)
Title: Improvements in or relating to artificial legs
IPC: A61F2/60
Filed: 1920-06-30
Abstract: 145,646. Beurdeley, A. Dec. 11, 1918, [Convention date]. Limbs, artificial.-An artificial leg is constructed with a special hip support and with an eccentric knee-joint mounting. Constructions of leg framings, artificial feet, and attaching harness also are described to illustrate the application of the invention. The hip support is formed by a stirrup 4, Fig. 1, which engages the thigh closely and is pivoted at each end to spring - mounted telescopic tubes which form part of the leg framing, and yield under the weight of the body. The pivots may be in the line of telescopic movement, as shown, or may be formed in rearwardly - extending lugs at the top of the telescopic member. Two bands are laced round the stump, one being fitted near the hip-support. To adjust the height of the stirrup, a second telescopic joint is introduced between the members 7, 8 of the framing, which is locked in adjusted position by a split screw clamp 13 or by a,cross pin passing through the member 8 and engaging one of a series of holes in the member 7. Pressure on the amputated stump is relieved by the use of the hip-support, since part of the weight of the body is transmitted through the hip-bone direct to the leg framing, and only the remainder transmitted through the stump and the bands to the framing. The knee-joint pivot is formed by eccentrics, integral with the upper ends of the lower leg strap 9, and working in eyes at the bottom of the members 8. The foot is double-pivoted to permit lateral rocking in addition to the ordinary swing- ing movement. The swinging movement takes place round the cross pin 27 and is controlled by a front tendon comprising a rubber spring 20 connected to an adjustable screwed rod 22, and by a rear tendon comprising a spring-controlled piston moving in a cylinder 19 filled with oil. The cylinder is connected to the foot by a hooked bolt 19<1> while the piston is connected to an adjustable screwed rod in the leg. Lateral movements are provided for by a hollow semi-cylindrical bearing 28 which provides a bearing for the pin 27 in its upper surface. The interior is charged with oil through the opening 28<1> and the oil escapes through holes 31 to lubricate the pin. The lateral rocking movement is controlled by adjustable spring rods 25 engaging the bolt 27. The space between the foot and the leg is covered by ' a shaped rubber ring 18. The toe is pivoted at 35, Fig. 2, and is restored by a spring 34, or alternatively, as shown in Fig. 6, by a spring tendon 37 passing from the leg through the heel to a screw turn-buckle 36 which is connected to the toe by a rod 38. A leather covering 33 covers the space between the upper part of the toe and the foot. The harness for connecting the leg to the body comprises a cord 44, Fig. 7, fixed at both ends to the leg and running on a roller 45 carried by a flexible suspension member 43. The member 43 is carried by a second roller 45 running on a loop passing under the near armpit and over the opposite shoulder. The part of the loop running over the back from the shoulder to the armpit is made of wider material than the remainder of the loop. The framing of the leg is built up of steel wire uprights suitably tied together and surrounded by plastic material to form an armoured casing.