Patent GB-819253-A (GB)
Title: Improvements in or relating to machine tools, for example multiple spindle automatic lathes
IPC: B23B9/10
Filed: 1956-05-01
Abstract: 819,253. Automatic lathes; chucks. CONE AUTOMATIC MACHINE CO. Inc. May 1, 1956 [Nov. 7, 1955], No. 13456/56. Class 83 (3). A multiple-spindle automatic lathe or other machine tool has a number of work-holders arranged in a frame, and corresponding reciprocable tool-holders operated through transmission members by cams, the latter being carried by a shaft housed in an aperture of the frame so that on removal of a bearing member covering the aperture, the shaft with its cams may be removed as a unit. The machine comprises a base 1, Fig. 1, supporting two columns 2, 3 with castcovers 4, 5 respectively, bolted over their top faces. A centre cover 6 is grooved to, and supported by, the covers 4, 5. A main overhead cam-shaft 43, Figs. 6A and 6B, is supported by the columns. The column 3 houses the crosstool slide assembly, the stock-feed gear and spindle-carrier indexing arrangement. The spindle-carrier, reciprocating gripper bar-stock feed and adjustable cam feed for the cross-slides are similar to those described in connection with " lone " multiple-spindle machines in Specifications 528,694, 634,518 and 657,898, [Group XX], respectively. The column 2 houses the end-working tool-holding arrangement and the drive and cam-feed mechanism for a number of auxiliary rotary-tool spindles such as 29, Fig. 6A. The cams such as 171, 179 are mounted on a vertical shaft driven by bevel gears 58-60 so that the cam assembly 61 may be easily removed as a unit from the casing B, when changing from one job to another. Five auxiliary spindles such as 29 are provided, around the axis of the usual reciprocable-tool rest 200, and are rotated by a gear 28. At a sixth position, a pick-off spindle 30 is employed which includes a chuck (see below) and may automatically pick up a workpiece from an oppositespindle position for a further operation or for later ejection. The cams such as 171, Fig. 12A, move cranked levers 173, pivoted about vertical shafts, through follower rollers 172 on one arm. The opposite arms carry adjustable pins 175 which engage slotted arms 176 of levers keyed to vertical shafts 168. The lower ends of these shafts carry arms such as 176a, Fig. 6A, which engage collars on rods 199 adjustably connected by brackets 125 to the auxiliary-tool spindles. The latter are returned by springs 177, 178, Fig. 12A. Stock-stops for bar speeds.-The side-tool rests 300, Fig. 27, are arranged fanwise and an elongated stock-stop 256 is arranged between the uppermost rest slides. The elongated stop enables the stock-feed mechanism to operate during the indexing of the turret. Clutch mechanism is employed to enable the tooling- mechanisms in the right-hand column to operate with the stock-feed, indexing, and locking drives of the left-hand column closed down. Provision is also made through clutch mechanism for " inching " and for reverse rotation of some of the controlling parts, with an interlock to prevent forward and reverse drives being operated at the same time. Chucks.-The bevel-closing pick-off chuck 30, Fig. 6A, is reciprocated similarly to the other end working tools; and a cam-operated quadrant rack in the end of a lever 120, Fig. 22, moves a pinion 121 to rotate a control shaft 123 for chuck operation. This control shaft is provided with right- and left-hand threads at its end, which engage rings 124, 125, for giving relative movement to the tubular parts of the chuck. A sleeve 126, moved by the ring 124, wedges a series of balls 128 into a groove to maintain the chuck in the closed position. An ejector is provided within the chuck spindle.