| 摘要 |
1,274,917. Automatic surgical injector. REX CHAINBELT Inc. 16 June, 1969 [28 June, 1968], No. 30302/69. Heading A5R. [Also in Divisions E2 and Fl] An automatic plunger release mechanism comprises a barrel 12, a spring 26 biasing a plunger 14 movable in the barrel between a retracted and extended position, lockable in its retracted position by means of balls 42 which engage recess 54 in the plunger 14, the balls being supported in a ball carrier 34 movably mounted on a guide 30 fixed to barrel 12, the balls 42 being engageable by an actuator 46 which is attached to a sleeve 44, movably supported on barrel 12. In operation, the device is initially cocked as in Fig. 2 and may be used to drive the needle of a serum injecting mechanism 25 (not described) mounted on a thread 24 on an adaptor 20. The carrier is engaged with a resistant surface and sleeve 44 is moved to the left, compressing spring 52, and causing actuator 46 also to move to the left so that balls 42 move free of portions 50 of the actuator. When this occurs, spring 26 drives plunger 14 in the direction of the arrow and head 56 cams the balls 42 outwards into bores 40 in the carrier 34. The plunger is then free for movement under spring 26 and carrier 25 is removed. To re-cock the mechanism (see Figs. 3 to 6), the exposed end of plunger 14 is engaged with a resilient surface and a force is exerted on cap 32 to compress spring 36. Head 56 engages balls 34 and moves them and the carrier 34 to the right until the balls pass locking portions 50 and are adjacent cam surfaces 48. Continued pressure then forces the balls outwards and head 56 moves past the balls. Then carrier 34 is free and spring 52 moves carrier 34 relative to actuator 46 so that locking portions 50 on carrier 34 engage the balls. The operation continues until head 56 abuts cap 32, when the force is removed. Carrier 34 continues to move until it abuts on base 28 as shown in Fig. 2. A lock may be provided to prevent accidental release, such as pins 58 engaging in recesses 60. |
