Patent GB-818887-A (GB)
Title: Improvements relating to machines for cutting gears and like toothed parts
IPC: B23F9/10
Filed: 1957-07-01
Abstract: 818,887. Gear-cutting. GLEASON WORKS July 1, 1957 [July 2, 1956], No. 20728/57. Class 83 (3). [Also in Group XXIII] A machine such as a gear-cutting or grinding- machine for spiral bevel and hypoid gears comprises a cutter 36, Figs. 1 and 3, on a slide 28 adjustable in a direction making an acute angle to the horizontal on a second slide 22 adjustable horizontally, the direction of movement of both slides being perpendicular to the cutter axis 37, and a work-spindle on a horizontal axis 53 adjustable in the same direction as the second slide. The slides 22, 28 are adjustable by wrenches applied to dials 25, 32 connected by gearing to screws 23, 29. The cutter head 34 is adjustable axially on roller bearings 38. The work W is mounted on a head 51 by a chuck operated by fluid-pressure means 56. The head 51 is adjustable about a vertical axis 48, intersecting the cutter axis, on circular guides 49 on a slide 43 adjustable transversely on guides 44 on a slide 41 movable to and from working position. The slide 41 is clamped in working position by clamps 42, each consisting of a T-bolt 254, Fig. 8, forced upwardly by hydraulic fluid directed to a chamber 246 by a valve 261, Fig. 15, operated by solenoids 262, 263. A main motor 59, Fig. 13, which drives the form cutter 36 through a magnetic clutch brake 61 and change gears 64, also drives a cam 67 on a shaft 68, through cycle time-change gears 72, to reciprocate a pump 208, Fig. 15, driving a work index piston 223, and controlling the clamping of the work spindle 52 during cutting as in Specifications 803,416 and 818,888. A second cam 78 on the shaft 68 moves the cutter head to and from working position through a lever acting on a follower which can be adjusted to determine the withdrawn position of the head. The cutter head may, however, be clamped in its advanced position if the cutter is a rotary broach. The work-head slide 41 is moved to and from working position, determined by the adjustment of a screw 105, Fig. 14, and a stop 116, by a piston 101 controlled by a solenoid-operated valve 264, Fig. 15. The last part of the advance movement is at slow speed determined by a throttle valve 139. The retracted position is determined by a stop 126 pushing a piston 125 against a dead stop 127 on an adjustable slide 122, the last part of the movement of the piston causing a throttle 137 to be brought into circuit to slow the movement of the head. Scales 142, 146, Fig. 1, are provided for adjusting the stops 127, 116, Fig. 14, together with a hand-held gauge 148. The gauge 148 is first adjusted by a screw 155 according to the plane P containing the cutter blade tips, and is then used to adjust the screw 105 to ensure that the gear-teeth are cut to correct depth. While the cutter 36 is being fed to depth, a cam 187 on the shaft 68 operates a piston 182, Fig. 15, to move an interconnected piston 165 bearing a roller 167, Fig. 12, engaging a cam groove 168 in a chamfering cutter slide 157. The slide 157 is mounted for initial adjustment in three directions, and carries a motor 158 driving a cutter 155 acting on the large ends of the teeth. The controls and valves, including switches for operating the main motor 59, Fig. 1, the chamfering motor 158, an hydraulic pump motor 193, Fig. 3, and a coolant pump motor 285, are contained in a cabinet 291. The main motor 59 is stopped when cutting is complete, by a counting device operated by a cam 289 on the shaft 68. A multi-section guard 293 is detachably connected to the base. In operation, a switch is closed to start the hydraulic pump motor 193, a workpiece W is placed on the chuck, and a switch is operated to actuate the device 56, Fig. 15, to close the chuck and to operate a switch 272. The operator then closes a further switch, causing the work-slide 41 to move to operative position where it actuates a switch to operate the clamps 42. The operator finally closes a switch to start the motors 59, 158, 285. The cutting then proceeds, with the cutter being withdrawn after each tooth has been out, to allow unclamping and indexing of the work-spindle. Specification 803,417 also is referred to.