Patent GB-166585-A (GB)
Title: An improved automatic screwing machine
IPC: B23G1/04
Filed: 1919-05-28
Abstract: 166,585. National Acme Co., Smith, O. A., and Rindfleisch, B. F. May 28, 1919. Screwing. -- In an automatic stud-threading machine, the blanks are fed from a hopper 100 to a lot in a block 5 through which they pass one at a time to a bore in the block in front of a pusher rod 22 which is operated by lever mechanism from the main cam shaft 38. They are transferred by the pusher rod to a position between spring gripping-jaws 26b mounted in jaws 26, 26<a> in the block; one of these jaws 26 is fixed while the other 26<a> is spring retracted and is moved forward in two stages with an intermediate pause to first position and then to grip the work by a wedge lever 10 and a lever 9 co-operating therewith. The lever 9 is operated from the main cam shaft and at its upper end, Fig. 1, is of two diameters, the larger diameter rolling on a fixed plate on the machine frame while the smaller diameter contacts with the under side of the lever 10, Fig. 5. The blank is pushed forwards against an adjustable stop 45<b> concentric with the die head and carried by a tube 45<a>, Fig. 13, which at its back end is adjustable in a fixed bracket 6 carried by the die-head housing 4. The dies are lubricated through this tube 45<a> by means of a flexible pipe 47 leading from an oil pump 48 driven by chain gearing from the maindriving pulley shaft 31. The main cam shaft 38 is driven from the pulley shaft 31 by a spiral gear 33 gearing with a similar spiral gear 34, Fig. 4, loosely mounted on a crossworm shaft 36<a> but adapted to be connected therewith by a clutch portion 52 which has a pivoted safety-lever 53 for connection to the shaft. The shaft drives through a further safety slipping connection the change gears 51 mounted upon a sleeve 57 connected to a worm 36 loosely mounted on the shaft, which in turn gears with a wormwheel 37 on the main cam shaft. A hand-lever 35 actuates the clutch portion 52 to start and stop the machine, and a hand lever 53<a> is provided on the worm-shaft to work the machine by hand when required. The die-head 28 is rotated by change-gearing 41, 41a, 41b from the pulley shaft 31, the gear 41b having longitudinal slots in its boss adapted to be engaged by rollers 44 carried by a part 43 into which the boss telescopes and which is secured to the threading spindle 29 carrying the die-head. The die-head is reciprocated to and from the work by a forked arm 80 carried by a shaft 67 which is slidably reciprocated in bearings on the machine frame by a dog 69 spring mounted between collars 81, 83 fixed to the shaft, Fig. 8. The dog slides on a rod 68 and is reciprocated by levers 70, 73 from the main cam shaft. The die closing and releasing head 28 is arrested just before the ends of the stroke of the die-operating gear 80 by stops 84, 84a, the inner die-carrying member moving on relatively to the head to close and open the dies. In case the dies are not opened after the blank is screwed, a stud 76 on the reciprocating lever 70 is adapted to actuate a trip catch 77 pivoted to the fork 79 which engages the die head 28 and to move the head positively in relation to the dies before the dies are moved backwards from the work. This trip catch is tilted to allow the die spindle to be drawn back in relation to the head 28 at the end of the stroke to close the dies by a stop 86 carried by a fixed part of the machine.