Patent GB-449910-A (GB)
Title: Automatic multiple spindle screw machines
IPC: B23B9/02
Filed: 1935-01-05
Abstract: 449,910. Lathes. FAIRWEATHER, H. G. C., 65, Chancery Lane, London.-(National Acme Co. ; 131st Street, Cleveland, Ohio, U.S.A.) Jan. 5, 1935, No. 460. [Classes 83 (iii) and 83 (iv)] Combined turning and drilling machines; rolling.-An automatic multiple-spindle screw machine particularly for making drilled parts such as nuts or rings has a pair of spaced carriers 5, 6 which rotate continuously in the same direction in unison, one of the carriers being provided with a number of rotary work spindles 7 while the other carries a number of aligned end-working tool spindles 11 which during the rotation of the carriers are reciprocated to and from the work spindles. The work spindles carry gears 8 driven either directly or through idlers according to the speed required from a central gear 9 on a central shaft 10. The tool spindles 11, Fig. 9, are also driven from the shaft 10 through a gear 13, 12 their direction of rotation being opposite from that of the work spindle there being either one or two sets of intermediate idler gears 12<1> according to the arrangement of the work spindle drive. In some cases the tool spindle drive may be disconnected so that the tool spindles remain stationary during operation. The stock feeding and chucking mechanism is of any usual type, and a disc 131 movable to permit withdrawal of the feed tubes, engages these tubes during their rotary movement. The work and tool spindle carriers are both secured to a member 14 carrying bearings 15 for the central shaft 10 which is driven from a pulley 18 through change gearing 31<1> and is supported at the end in a bracket 19. One or more stationary work stops S are provided. The shaft 10 is also connected through bevel gearing 20, 23, and change gears 31 to a longitudinal spindle 25 which is connected through bevel and worm gears to drive worm wheels 35, 30 on the work and tool carriers respectively. For feeding the tools sequentially towards the work the tool spindles are normally retracted by springs 40 to engage sliders 38<1> carrying rollers contacting with a fixed cam 36 so that as the tool spindle carrier rotates the tools are progressively fed into and withdrawn from the work spindles, the depth of cut being determined by the rise of the cam 36. The driving shaft 25 is connected by belt gearing to a cam shaft 46 carrying a drum 47 operating lever mechanism A, B, the chucks being successively opened by lever B, closed by lever A on completion of the feed after which lever B is returned to position to coact with the next spindle. The drum has three sets of chuck operating cams and three sets of feed cams so that stock is fed through three spindles at each revolution of the cam drum. No side working tools are provided but a number of stationary tools are arranged round the work carrier housing. Thus the spindles in their orbit may first pass a forming tool 47<1>, Fig. 9a, then a knurling tool 48 and then a cut-off tool 50 each tool coacting simultaneously with several spindles. The spindles then pass through a gap 51 where the bars are fed. The stationary tools may be arranged inside the orbit of the spindles. Milling cutters may be used in place of the stationary tools. In Fig. 11 rotating tools 52 such as drilling cutters knurling, numbering, or burnishing tools may be used. In a modification Fig. 22, a chain or belt drive pulley 20<1> drives the shaft 10a geared to shafts 10b, 10c and 251, a friction clutch being provided between shafts 10b and 10a.