Patent GB-618417-A (GB)
Title: Improvements in automatic lathe or screw machine
IPC: B23B7/04
Filed: 1945-06-27
Abstract: 618,417. Lathes. CONE AUTOMATIC MACHINE CO., Inc. June 27, 1945, No. 16442. Convention date, May 6, 1944. [Class 83 (iii)] A single spindle automatic turret lathe comprises an indexing turret, a number of tool holders carried by the turret adapted to be moved sequentially into and out of operative relation to the work, a lever, fulcrumed on a reciprocating support, one arm of which carries a follower for engagement with a first cam which is driven continuously, another arm of said lever engaging one of said turret tool holders when in the appropriate indexed position of the turret, the said support being intermittently reciprocated by a second cam driven intermittently, the first cam controlling the productive motion of the said tool holder and the second cam controlling the non-productive motion of the tool holder. The machine frame comprises a bed 1, Fig. 4, from which, at each end, rise hollow columns 2, 3 connected by an overhead hollow triangular section member 4. The single work spindle 5 is journalled in the column 2 and employs known devices for automatically opening the chuck and feeding the stock at intervals against a stock stop 99, Fig. 12. The latter is carried by an arm 100 adjustable longitudinally along a bar 95 which is mounted in a slide 97, Fig. 4, under control of a cam drum 90 forming part of the main cam control carried by the overhead cam-shaft 60. A spiral wheel 105 fixed to the bar 95 engages a stationary rack 107 to oscillate the bar and stock stop on longitudinal feed of the slide 97. Cross slides 50-53 are operated from the main cam-shaft, the upper slides being carried by the overhead member. Feed motions.-A shaft 6 parallel to the spindle and supported at each end in the frame columns rotatably carries a pentagonal turret 17 on the faces of which tool slides 20 are arranged. Each tool slide has an extension block 23, Fig. 18, and rod 221, a slot 24 in the extension is adapted to line up with an annular channel formed between flanges 27, 28 in the webbed extension and supporting member 12 for the turret. Arcuate flanges 33 on a divided upright 32 extend into the annular channel but leave the top opening free, this ensures that all the tool slides are held by their slots 24 except that in the top or working position which is free to be fed axially in this position. A follower 130 on the lower end of a lever 124, Figs. 4 and 13, engages the slot 24 of the tool slide in this top position. This lever is pivoted at 125 to a sliding block 126 and carries at its other end a follower 123 adapted to engage either camplates 121 or the rim 122 of a cam drum 120 on the main cam-shaft 60. The block 126 is moved by a cam drum 136 on a secondary shaft 138 for rapid feed of the tool slide into and out of working position while the working feed is effected by the cam plates 121, the pivot 125 and block 126 meanwhile remaining stationary. The rods 221 carry adjustable stop nuts 220, 222, Fig. 15, which positively limit the feed movement towards and away from the work respectively. The secondary shaft 138 is rotated intermittently and independently from an electric motor 145 and a sprocket chain, Fig. 13, at timed intervals under control of the main cam-shaft 60. The motor is continuously rotated, but a clutch 155 is engaged at intervals to rotate the shaft 151 and worm drive 1510, 1511 rotating the cam drum 173 through a safety shear pin 1512, Fig. 15. The rear end of the cam-shaft 60 is provided with a number (equal to the number of turret faces) of axially spaced discs 170, Figs. 15 and 16, each having a finger 171 positioned by a scale and adapted to strike shorter fingers 178 on a member 180 secured to shaft 165. Also secured to the latter is a star-wheel 190, the projections on which are struck intermittently by a roller 188 on a member 185 secured to a secondary cam-shaft 138. The fingers 171 are adapted to rotate the shaft M5 intermittently, a pentagonal disc 164, Fig. 13, carried by this shaft engaging pins 162, 163 on a rod 158 to move a bell-crank 156 and engage the clutch 155. The secondary cam-shaft through the roller 188 and projections on the star-wheel 190 effects disengagement of the clutch. Rotating and locking turrets.-The member 185, Fig. 16, through a cam rim 186 and roller 187 unlocks and indexes the turret through the latch-operating lever 200 and the Geneva wheel 195 respectively. The shaft 151 for driving the secondary cam-shaft may also be rotated bv a hand wheel 232 which when not in use is removed from the shaft and hung in the reverse position to cover the shaft-end. The clutch 155 is interlocked with a clutch 2350 so that when the former is disengaged the latter is engaged. The hand wheel 232 when in use thus serves also to rotate a worm-wheel 236 with limit stops 238 which positively limit the amount of hand adjustment and automatically operate a switch 240 to open the circuit to the motor 145 and the main drive motor 300. Spindle drive.-The machine spindle is driven from a main electric motor 300 through V-belts 311 and a chain drive, change speed and pickoff gearing all carried in a detachable housing 303, Fig. 3, being provided. A main clutch and brake are provided in this drive, operable by hand or automatically from the cam-shaft 60. This cam-shaft is driven at high or low speeds through a shear-pin safety device and rotates always in the same direction by the provision of one-way drive clutches regardless of a reverse drive for the spindle being engaged. The change speed and reverse devices for the spindle are effected through clutches operated by hand or automatically from cam drums 420. 421, Fig. 4. on the turret-supporting shaft 6. Interlocking gear is provided for preventing more than one clutch for the drive being closed at any one time.