GB594107A - Improvements in or relating to automatic drilling machines - Google Patents

Abstract

594,107. Drilling. BRITISH TABULATING MACHINE CO., Ltd., and VINES, W. C. June 26, 1945, No. 16302. [Class 83 (iii)] In a drilling machinewith automatic devices for bringing and registering work-pieces into position to be drilled, clamping them during drilling and ejecting them after drilling, the automatic devices are operated electrically by contacts operated by cams on a slow speed shaft driven from the drilling spindle and mechanically connected to the feeding means of the drill. The drill spindle 1 has a pulley 5 and gear-wheel 4 splined to its upper end and is journalled in a sleeve 2 reciprocable in a guide 3 of the frame by means of a rack 6 and a pinion 7 on a shaft 8. A cam 13, on a slowspeed shaft 14 driven from the gear-wheel 4 by reduction gearing 15, 17, 18, 20, 21, feeds the drill up and down by means of a spring-returned rack bar 11 and another pinion on the shaft 8. The slow-speed shaft also carries three cams for operating contacts in the electrical circuit. The work-pieces, such as terminal posts 43, are fitted in holes 47 and scallops 48 in a plate 41 fixed to an indexable table 27 provided with ratchet teeth 29. A ratchet 30 engages the teeth 29 and is reciprocated by the plunger 32 of a solenoid 34 ; a plunger stop 38 and locking stop 40 are provided. For holding a circular work-piece against rotation and for registering it correctly at the drilling station 45, a lever 51 is pressed against the work-piece by the 'energizing of an electromagnet 53. If the work-pieces are held against rotation by reason of their form, the lever 51 is employed only for registering, being given a V-shaped end engaging notches in the plate 41. A stop 54 is provided for the lever. The drilled workpieces are ejected by a lever 59 engaging under the shoulder of the work-piece and tilted when an electromagnet 57 is energized ; a stop 61 is provided. If the work-pieces are of a size larger than the pitch of the teeth 29, the cam for the solenoid 34 may be shaped to energize it twice in rapid succession, so rotating the table by the pitch of two teeth at each operation.