GB117837A - Improvements in or applicable to Lathes and other Machine Tools for Facilitating their Operation. - Google Patents

Abstract

117,837. Carson, J., Churchill, A. L., and Gabriel, J. W. W. July 28, 1917. Lathes; driving machines. - A lathe, drilling-machine, or other machine is provided with fluid-pressure means for automatically controlling the mechanical operation of the various parts. The parts are actuated by pistons in cylinders, the admission to and exhaust from which are controlled by valves actuated indirectly by adjustable cams on an intermittingly rotated cam drum. The following operations in a lathe are performed in the order given with the work initially rotating. The leadscrew nut engages the lead-screw a<3> which is driven through a clutch b from the change-wheel drive; the tool is given the necessary movement for the cut; the slide carrying the tool is fed up to the work; the clutch b is operated to operate the screw a<3> ; the nut is opened at the end of the traverse; the slide is operated to withdraw the tool; the saddle is returned to its starting position; the clutch b is opened to disengage the lead-screw; the nut is re-engaged and the cycle is repeated until the necessary number of cuts have been made; and the lathe is finally stopped. The various valves are operated by a series of cams on a shaft d, Figs. 1, 3, and 4, in a frame d' which is rotated by worm gearing e', e driven by a shaft e<2> from a continuously rotating pulley c<3> through a friction clutch f held in engagement by a spring and disengaged by a bell crank f<2>, one arm of which carries a fork engaging a groove in the clutch, and the other arm f<5> is actuated by a disk f<6> carrying cams f<7>, f<8> which engage the end of a bar f<3> slidable in the arm f<5>. The bar f<9> is actuated by a piston i<3> operated by fluid-pressure controlled by a valve h<9>, Fig. 8, in a casing through which slides a bar h' with cam surfaces h<2>, h<3>, h<4>, h<5> which actuate a slide h<6> and lever h'. The bar h<1> is secured to a rod g carrying adjustable tappets g', g<2> and retained in a. central position by a spring g‹. The slide h<6> actuates through a spindle h<8> the valve h<9> when a detent h<10> is withdrawn by the action of cams h<4>, h<5>. The valve is returned by a cam h<12>. The rod i<4> of piston i<3> has a pawl i<5> which moves a pawl i<6> to withdraw the bar f<9> and moves the clutch f to rotate the shaft d, the positioning of which is determined by a locking-bar k which engages notches f<10> in the disk f<6>. The bar k is withdrawn by a lug k<2> on the bar f<9> engaging a lug k<1>. The pawl i<6> is held in engagement with the pawl i<5> by a lever operated by a cam l<1>. When the pawl i<6> is lowered, the bars f<9> and k are released. The bar k locks the disk after one of the cams f<7>, f<8> has engaged the bar f<9> to rock the bell-crank f<2> to disengage the clutch f. The valve m<1> controls the cylinder m actuating the lead-screw nut by means of a lever m<0> carrying the hand-lever m<2>. The valve m<1> is actuated by cams m<3>, m<4> adjustable in a slot in a drum m<x> mounted on the shaft d. The cams m<3>, m<4> engage tappets m<8>, m<9> on a lever m<6> pivoted at m<7> and connected to the valve m<1>, Fig. 11. The feedscrew of the tool-slide is actuated by a cylinder controlled by adjustable cams n<2>, n<3> and actuating a lever n<5> operating a ratchet wheel n<6>. A stepby-step movement is provided by means of a snail cam o, Fig. 13, rotated by ratchet mechanism o<1>, o<2> actuated by a cylinder o<4>, the valve of which is actuated by adjustable stops p<1>, p<2>. The toolcarrying slide is moved up to the work by a rack and pinion q<1>, q<2> actuated by a cylinder q controlled by cams q<3>, q<4>. The clutch b is actuated by a cylinder r controlled by cams r<2>, r<3>. The saddle is returned by air in a cylinder s<2> controlled by cams s, s<4>. When the tool has been moved forward to the requisite depth of cut, a pin t, Fig. 13, on the cam o stops the lathe by actuating a lever connected to a two-way cock which controls a cylinder t<4>, the piston of which carries a rod t<5> carrying a strap fork t<6>. The saddle may be returned by a spring, weight, or rotary motor operating a pinion a<6>.