Improvements in and relating to work-holding and positioning means for use in metal-cutting machine tools

摘要

407,761. Making needles &c. FAIRWEATHER, W. C., 65, Chancery Lane, London.-(Singer Manufacturing Co. ; Elizabeth, New Jersey, U.S.A.) Oct. 21, 1932, No. 29466. [Classes 83 (ii) and 83 (iii).] Milling; blanks, transferring.-In a device for positioning round longitudinally grooved articles, such as sewing-machine needle blanks, so as to be presented correctly for a machining operation, the article is frictionally rotated and is arrested in a definite position by a yielding detector which engages the longitudinal groove. As applied to the machining of needles, such as milling near the eye or slabbing of the shank, the needles are fed one at a time along a groove 11 in the bed 1, point first, towards the holding jaws 4, 7. Both jaws are pivoted to the bed at 11, the jaw 4 having an extension 41 connected by a linkage 20, 18, 17, 71 to the jaw 7 so that the two jaws oscillate about the pivot 11 in opposite directions. A spring 10 acting on the extension 41 normally maintains the jaws closed. The jaw 7 is grooved at 21, Fig. 6, to receive the cylindrical shank of the needle and the jaw 4 has a semi-cylindrical recess 5 to receive the blade of the needle and a depression 22 for the end of the shank, the recesses 5, 22 being formed in an interchangeable block 2 attached to the jaw 4. The jaw 7 is also replaceable to suit different sized needles. A spring blade 8 attached to the jaw 7 projects up through a slot 9 in the jaw and into the recess 5 so that as a needle is fed axially between the jaws, its shank is rotated by a friction roller 6 until the end of the blade engages the longitudinal groove therein, thus positioning the needle for the machining operation. On completion of the machining operation, the jaws are released by a cam-actuated lever 14 having an adjustable screw 15 engaging a projection 13 on the jaw 7. Whilst the needle is being machined, its free end is held by a chuck, (not shown). The closed position of the jaws 4, 7 is determined by an adjustable stop contacting with a projection on the jaw 7. Specification 26096/11, [Class 83 (iv)], is referred to.