Patent GB-189808349-A (GB)
Title: Improvements in Machines for Cutting Gear Wheels.
Inventor: JUSTICE PHILIP MIDDLETON
Filed: 1898-04-07
Granted: 1899-04-07
Abstract: 8349. Justice, P. M., [Sager, J. H.]. April 7. Milling.-Relates to a gear - cutting machine particularly suitable for producing wheels to gear with pin-wheels. The rotating cutters H are mounted in a slowly-rotating mandrel F, the size and position of the cutters corresponding, in the machine shown, to alternate pins on the wheel which is to gear with the blank X to be cut. Fig. 10 shows a diagram of the cutting operations. The blank X, which may be previously slotted at 1, 3, 5, 7, &c. to relieve the cutters, is slowly rotated in the direction of the arrow. The cutter H having engaged the space 1 and cut the faces 2, the next cutter engages the alternate space 5, cutting the face 4 during approach and the face 6 during the recess, each cutter engaging alternate spaces, thus requiring two revolutions of the blank to complete it. Fig. 2 shows a plan of the machine. A bed-plate A has mounted on it a slide-rest B<1> with slides B, B<2>, on the upper of which is mounted a standard B<3>, Fig. 5, carrying a chuck for holding the blank X. The slide-rest can be slewed on the bed, allowing the position and angle of the blank with respect to the cutters to be varied. The chuck consists of plates C<10>, C<20> on a divided shaft C<1>, C<2>, the plates being drawn together by a collared screw C<3>, on the shank of which the blank fits. The shaft is rotated in the bearings b<30>, b<3> by a gear-wheel C driven by a wheel F'. The wheels F<1>, C are change-wheels corresponding to the velocity ratio of the pin-wheel and the blank. The cutters H, shown as four in number, have cylindrical shanks fitting in split sockets H<1>, Fig. 5, tapered externally and screwed in spindles G to hold the cutters. The spindles are mounted in a mandrel F secured to a sleeve e, the parts revolving in bearings d, d<1 >on the cutter head D. The bearing d<1> is recessed to receive the hub y‹ of the driving-pulley Y, which rotates on the sleeve e. The pulley has an internal wheel Y<01>, Fig. 7, which engages teeth g on the spindles G, driving the cutters at a high speed. A toothed ring y on the pulley hub is connected by gearing y<1>, y<12>, y', y<22> to a toothed sleeve y<3> loosely mounted on a worm shaft y<4> and forming part of a clutch, enabling it to be coupled up to drive a worm-wheel E on the sleeve e. The mandrel F is thus rotated at a slow speed, and the wheel F<1> on it drives the blank at a further reduced speed. The worm shaft may be set by a hand-wheel y<43>. After starting the belt pulley and cutters, the clutch is engaged by a handle Y<10> connected to a bell crank Y<7>, which operates the clutch through a slide block y<6>. This bell crank is also connected by a rod Y<8> to a bell crank Y<9>, which retracts a spring bolt C<5> from a socket C<10> in the wheel C, allowing the blank to rotate. The bolt is then held out of engagement for two revolutions of the wheel C and blank by a disc C<6> engaging a lug c<05> on the bolt. The cutting of the blank is then completed, and an aperture c<6> in the disc is brought opposite the lug c<05>, allowing the bolt to spring into the socket, locking the wheel C and disengaging the clutch to stop the mandrel. This mechanism may be applied to stop the blank in any desired position. Cutters may be employed corresponding in number to the number of pins in the pin-wheel to be used, or only one cutter may be used.