| 摘要 |
1,254,190. Chucks. JACOBS MFG. CO. 25 April, 1969 [18 June, 1968], No. 21192/69. Heading B3B. A portable rotary power tool, particularly adapted for bone surgery, has a spindle 13 carrying a chuck 10 provided with a jawactuating unit 21 and a collar 29 which in its normal position locks the unit 21 against rotation relative to the chuck body 11 in a jawslackening direction but allows rotation in the jaw-clamping direction, the collar 29 being retractable manually against the pressure of a spring 37 to bring lugs 44 on its rear end into engagement with slots 33 in the tool casing 16 to lock the spindle and chuck against rotation relative to the tool casing. The collar 29 is slidably but non-rotatably mounted on a portion 31 of the chuck body, which portion may be, e.g. squared, polygonal or splined. The jaw-actuating unit comprises a manuallyrotatable sleeve 19 mounted on the chuck body 11, a nosepiece 22 and a jaw-carrying cage 26, the jaws 24 being toothed to engage a conical threaded portion 28 on the chuck body. In the normal position of the collar 29 ratchet teeth 39 thereon engage projecting teeth 41 on the rear end face of the sleeve 19. Retraction of the collar and operation of the jaw-actuating unit can be effected with a single hand by the tool operator while the tool casing is held in his other hand. Reference has been directed by the Comptroller to Specification 1,087,251. |
