Patent GB-191101542-A (GB)
Title: Improvements in Automatic Turret Lathes.
Inventor: CONRADSON CONRAD MARTINIUS
IPC: B23B7/12
Filed: 1911-01-20
Granted: 1912-01-22
Abstract: 1542. Conradson, C. M. Jan. 20. Lathes.-An automatic turret lathe has means whereby the machine is operated automatically through a complete cycle of the machine by mechanical means instead of fluid pressure means, and has mechanism for returning the feed-con trolling members to their initial positions after the operation of the last tool in the turret. The work w is held in a chuck W on a fixed headstock on a bed A, and is rotated through the cone pulley W<1>, which also drives a train of wheels g, g<1>, g<2>, g<3> mounted on the end plate a<2> of the frame. Tool and saddle feed-motions; reversing- mechanism.-The last member of the train is mounted on a spindle s, which drives through bevel-gearing a shaft s<2> carrying a pinion g<6> at its end, which can gear with gear-wheels g<7>, g<8>. These are arranged one on each side, and are mounted on pivoted arms and adapted to drive, through screw gearing and a movable clutch, a shaft V at either of two speeds, the clutch being operated from a cam-plate T'. A shaft V<1>, parallel to the shaft V, is driven directly from a pulley V<2> at a constant speed, this shaft carrying a gear-wheel v<1> at its inner end, engaging a loose pinion v<3> on a shaft S'. A pinion v on the shaft V engages a loose pinion v<2>, also on the shaft S', and this shaft is adapted to drive the feeding-screw R in one direction through gearing v', v<6>, and in the reverse direction through gearing v<5>, v<7> and intermediate idle pinion, the drive being regulated by clutches C<1>, C operated from a cam-plate T through levers. Turrets.-The turret tool-holder D is rotatably mounted in a slide D<1>, which is traversed by the screw R, and is locked in each position corresponding to a tool by a locking-pin O, unlocked at the end of the traverse of the carriage through a lever o<2> by means of a reciprocating rod E mounted in the slide D' engaging a fixed stop E' on the machine frame. A cam e<5> on this rod actuates the pin, after which a rack on the side of the bar E, driving a clutchwheel J, Fig. 16, causes this wheel to engage a spring pawl J' in the turret extension to rotate the turret until a flat surface j<2> on the wheel engages the surface e<4> on the bar E, a hook e<3> preventing slip. The rod E is returned by a spring e' as the slide moves forward again, the pawl o<3> on the end of the lever o<1> being pivoted so that the locking-pin is not retracted, it having in the meantime been snapped into engagement by a helical spring. Turret and like stop-bar selector mechanisms; speed-controlling mechanism.-A selector stopbar P is rotated synchronously with the turret through chain gearing F, this stop-bar having a series of stops p, p<1>, p<2> mounted on each face thereof to suit each individual tool, except that on the face corresponding to the first traverse of the turret the stop p<2> is omitted, there being as many faces to the stop-bar as there are tools in the turret. By means of these stops, which actuate a system of levers, the rotation of the shaft M which carries the cam-plates T, T' is controlled. For this purpose, bell-crank levers n, n<1> are pivoted on the front plate of the machine and are connected together, Fig. 20, the lever n adapted to be operated by stops p, p', being in a different plane to the lever n<1> which is actuated just before the end of traverse of the turret slide by a stop p<2>. By means of these stops, the ends of the levers are depressed, actuating a lever. n<4> connected to a piece m integral with the handle m<1> and rotatably mounted on a pin k<2>, Fig. 20, carried on a sleeve D<2> fixed to the machine frame. Integral with the piece m is a spring pawl r<3> adapted to engage a notch in a piece m<2>, also rotatably mounted on the pin k<2>, and to rotate it, thus allowing the end of a spring pawl r<5> to drop into a notch m<2>, the other end of the pawl then engaging a continuouslyrotating ratchet-wheel U, and thus communicating rotation to the sleeve U<1> on which the pawl is mounted. A stop r<4> on the sleeve U<1> disengages the pawl r<3> from the part m<2>, which is then returned by a spring to its normal position to disengage the pawl r<5> from the ratchet-wheel after one revolution of the shell U<1>, the pawl being again released on the next depression of the handle m<1>. The shell U<1> rotates the shaft M through spur and screw gearing M<1>, Fig. 2, so that the cam-plates T, T<1> are partly rotated for each depression of the handle m. The number of cams on the camplate is limited to thirty-two, giving thirty-two complete operations of the actuating clutches to each cycle of the machine. Preferably, the shaft M should start from a constant angular position at the commencement of each cycle of the machine, and if the whole of the thirty-two motions are not used, means are adopted to rotate the shaft M idly after motion of the turret slide has ceased. For this purpose, a pin-wheel L is mounted to rotate with the shaft M, this wheel carrying a number of pins l which can be pushed and retained into engaging or disengaging position for the end m<5> of a lever, which is attached by a link to the actuating-handle m<1>. After the shaft M has been actuated according to the number of tools in the turret, and just as the last stop p' leaves the lever n in the last backward movement, the first pin l on the controlling-device comes into actuation and lifts the end m<5> of the lever m<4>, and so ensures continuous rotation of the cam shaft to the initial position. The cams on the cam-plates T are of such a nature as to keep the reversing mechanism of the turret carriage in gear until the carriage has come into the position ready for a new cycle, whereupon cams which throw the clutch levers into the neutral positions come into operation.