Patent GB-190101078-A (GB)
Title: Improvements in or relating to Drilling or like Machines.
Filed: 1901-01-16
Granted: 1902-01-16
Abstract: 1078. Pierpont, F. H., and Lanston Monotype Corporation. Jan. 16. Drilling.-Relates to a machine for accurately positioning and forming a conical or other shaped hole in a body, being specially suitable for, and described with reference to, the drilling of a conical hole in the end of a matrix blank such as is employed in the monotype casting and composing machines described in Specifications No. 13,267, A.D. 1897, and No. 8633, A.D. 1899. The machine has a headstock A<3>, Fig. 1, in which is a hollow spindle B with a chuck cavity B<2> in which the blank, Fig. 15, is held while being drilled. A constantly-driven pulley C<6> is automatically coupled to the spindle by a spring clutch, hereinafter described, when the clutch is released from a hook on a rock shaft D. A turret E, capable of reciprocation and rotation in a casing E<1>, has on its front end blank-holding compartments E<6>, E<6>, Fig. 4, and tools <E>, E<8>, while its rear end has an annulus E<3> and a disc E<2>. The annulus is formed as a wide ratchet-wheel operated by a pawl pin on a hand-lever F, pivoted on the turret and having its lower end guided in a way A<5> so that it may also serve to advance and retract the turret. The disc E<2> is formed as a cam to rock the shaft D and allow the clutch to engage the spindle B. The blanks are preferably supplied to the machine in long cases or galleys G, one of which is inserted in a slide-way A<9> on a standard. A similar case is preferably supported horizontally in front, as indicated in dotted lines in Fig. 4, to receive the discharged blanks. The operation of the machine, commencing with the position shown and with a finished blank in the spindle, is as follows :-The turret is moved forward, being registered by a pin E<11> on the casing engaging a slot E<10> in the disc E<2>, so that the compartments E<5>, E<6> are respectively opposite the lower or supply end of the feed-race G<4> and the stationary spindle. An adjustable stop H<1> on the turret moves forward a rod H, operating an ejector rod B<3> to push the finished blank into the compartment E<6> . and a pusher rod (not shown) to push a fresh blank into the compartment E<5>. The turret is now drawn back, and rotated one step until the pin E" registers with another slot E<16>, the fresh and finished blanks being respectively opposite the spindle and discharge race J<1>. The advance of the turret causes the pin E" to strike one end of a lever E<13> pivoted in the turret and projecting into the slot E<16>, and thus to operate two ejector rods to transfer the fresh blank to the spindle and the finished blank to the discharge race. A bevelled tooth J<4> on the front of the turret actuates a spring pusher J<2> at right-angles to move on the previously-inserted blank. The shaft H and the rods connected therewith are restored by the fresh blank in the spindle moving the rod B<3>. The turret is again drawn back and revolved, causing the cam disc E<2> to rock the shaft D and allow the pulley C<6> to become coupled to the spindle to rotate it. The turret is advanced, the pin E" engaging a slot E<17>, and the tool E<7> roughly forms the hole. The turret is again operated for the pin E" to engage a slot E<18>, and the hole is finished by the tool E<8>. The next operation of the turret causes the cam E<2> to rock the shaft D and uncouple the clutch, the parts resuming their initial positions. More than two tools may be used if extra registering-slots are provided in the disc E'. The clutch for connecting the pulley C<6> to the spindle B is shown in Figs. 10 and 11, and comprises a sleeve C, secured to the spindle by a set-screw C', and a sleeve C<3>, screwed on one end of the sleeve C, and having a slot C<9> to receive the head of the screw C'. The sleeves have coned friction surfaces to engage with similar surfaces on the pulley, the sleeve C<3> being normally screwed against the pulley by a coiled spring fastened to the sleeve and the screw C<1>. To stop the spindle, the hook on the rock shaft D is moved into the path of an offset C' on the sleeve C<3>, thus screwing it back from the pulley and disengaging the clutch, the spindle being held by the engagement of the screw with the opposite end of the slot C<9>. The blank is held in the chuck cavity in the spindle by a cap with an aperture of the same shape as the cavity, but held out of register therewith during the rotation of the spindle to keep the blank in place. A second hook on the rock shaft engages an offset on the cap when the clutch is disconnected, and holds the cap in register while the spindle is stationary to allow a blank to be inserted or ejected.