Patent GB-191117540-A (GB)
Title: Improvements in Artificial Limbs.
Inventor: IMRAY OLIVER
IPC: A61F2/58
Filed: 1911-08-01
Granted: 1912-05-16
Abstract: 17,540. Imray, O., [Carnes Artificial Limb Co.]. Aug. 1. Limbs, artificial.-An artificial arm, primarily intended for use in cases of amputation below the elbow, comprises a sleeve for the upper arm, a fore-arm A, a rotatable wrist C' and a hand C which is hinged to the wrist and is provided with a resiliently - mounted thumb having a hook, with hinged fingers and finger tips, and with a coin receptacle and pencilholder; locking means and operating mechanism are also provided. The wrist is locked by a bolt L which is pressed through holes in the plates M, N of the fore-arm and wrist by a spring l<2>; it is unlocked by bending the elbow and so causing a rod F to actuate a wheel E secured to a shaft D' longitudinally slidable in the forearm, and a projection e<1> on the wheel to push back the bolt so far that the shoulder j<1>, Figs. 9 and 18, of a lever J, which is pivoted at j to the plate M and pressed by a spring J<1>, is no longer held back by a projection l but catches before it and retains the bolt. As the shoulder j<1> moves upwards, an extension J<2> of the lower end of the lever J falls, and with it the shaft D<1>, so that a catch d' on the shaft engages a loosely-mounted bevel-wheel D in gear with a wheel N<1> secured to the wrist. The wrist can then be rotated by straightening the arm. The lever J is turned back, so that the bolt L is released to lock the wrist in its new position and the shaft D' lifted to disengage the catch d<1> from the wheel D, by movement of the shoulder or upper arm to turn, through cords and pivoted levers, a loosely mounted plate H having a shoulder h, Fig. 9, which tips a bellcrank lever I engaging the upper end of the lever J. The hand C. fingers F, Fig. 10, and finger tips 1 are hinged to the wrist, hand, and fingers respectively by pins p, 6, 6<1> and socket joints. The hand is locked in any position by a spring-pressed toothed lever P<2>, Fig. 7, but may be bent in or out by moving back the catch P<2> by a latch p' and slightly straining the cord Q or cord Q<1> by moving one or other of the shoulders so as to pull on a transverse shaft R mounted in the hand. The fingers and tips may be bent or straightened by locking the hand and increasing the strain on the cord Q<1> or Q so as to rotate the shaft R and operate the cranks and connecting-rods R<3> pivoted to the fingers, the tips being bent relative to the fingers by the action of bars 5 which are pivoted on the hand C and the pins 6 and connected by links 10 to the tips. The thumb 12 is hinged to the hand by a slotted extension 13 pivoted in a socket 15 in the hand by a pin 14, and is held resiliently by springs 21, 25 connecting the hand and thumb respectively to a slotted plate 17 which is mounted in the slot of the extension 13 and engages stops 19, 22 on the hand and extension respectively. The thumb is provided with a hook 27 pressed outwards by a spring but normally retained by a dog 32 which may be released by pressure on a stud 33; after use, the hook is pushed back. The fore-finger has an outwardly-pressed pencilholder 36 which is similarly controlled. Coins may be held in a recess 43 in the hand by spring pressure, and may be discharged singly by a spring-actuated plate normally held by a spring-pressed dog provided with an external operating knob; the plate is returned to its normal position by closing the fingers and so operating a slotted link pivoted to the rear of one of the rods R<3> and in engagement with a stud on the plate.