AN IMPROVED DEVICE FOR THE ATTACHMENT OF TOOLS FOR TAPPING AND STUDDING OPERATIONS TO POWER OPERATED DRILLING AND LIKE MACHINES

摘要

1,204,482. Tapping or studding attachment. CLYDESIDE MACHINE TOOL CO. Ltd., and G. W. BOXALL. 10 Nov., 1967 [14 Nov., 1966], No. 50878/66. Heading B3N. A tapping or studding attachment comprises a sleeve 21, a tool or stud holder 27 slidable in the sleeve, and a drive member 13 secured to a shank 10 by a shear pin 14, and connected to sleeve 21 by a slipping clutch 34. Holder 27 is slidable in a square-sectioned bore 19, and has a bolt 41 screwed therein which supports two conical springs 22, 23, and abuts a third conical spring 17a. Sleeve 21 is held in member 13 by balls 36 which are releasable by sliding a ring 39 so that the balls enter an annular recess 40. At the commencement of a tapping operation the drilling head to which the attachment is fixed, moves towards the work, and springs 22, 23 are extended. The tap is arrested as it abuts the work, so that spring 17a is compressed. The tap feed is now controlled by the pitch of the thread, and springs 22, 23 are compressed until the machine is reversed, whereupon the tool returns to the Fig. 1 position.