| 摘要 |
684,888. Hypodermic injection devices. BECTON, DICKINSON & CO. Jan. 15, 1951 [Feb. 7, 1950], No. 1104/51. Class 81 (ii). Hypodermic injection apparatus includes a medicament chamber wherein a needle assembly, which supports a hypodermic needle, is movably mounted so that the needle is projected through an aperture in an end member of the apparatus when the needle assembly is moved towards the end member, resilient means being provided for urging the needle assembly towards its retracted position, and a power-operated plunger to cause projection of the needle assembly and expulsion of medicament. The medicament receiving chamber is included within a casing 10 which also houses an electromagnet 31 and a plunger 28 connected with an armature 29 which is normally held in retracted position by a spring 30. A slidable sleeve 21 is provided with a transverse wall 24 fitted with a cannula 25. An ampoule tube 17 fitted with a piston stopper 18 and another stopper 19 is contained within the sleeve 21. A skin-contacting cap 15 is provided internally with a spring 16 which normally holds the sleeve 21 in retracted position. When the electromagnet 31 is energised by operating a control device 32, the armature 29 and piston 28 move forwardly, the latter pressing against the piston stopper 18. The ampoule, sleeve 21 and cannula 25 are thus caused to move forwardly until the spring 16 in the cap 15 is fully compressed, the cannula 25 being projected from the apparatus to penetrate the tissues. Further forward movement of the armature 29 and piston 28 pushes the piston stopper 18 into the ampoule 17 to expel medicament through the cannula 25. After discharge of medicament the electromagnet 31 is deenergised and the armature 29, piston 28, ampoule and the sleeve 21 carrying the cannula 25 are retracted by the action of the springs 16, 30. Inspection openings 26, 27 are provided in the casing 10 and the sleeve 21. The removal of the cap 15 permits removal of the sleeve 21 and cannula 25 for sterilisation, the renewal of the ampoule 17 and the replacement of parts for re-use. |
