| 摘要 |
1,254,847. Gear cutting; machine tool details. LAPONTE MACHINE TOOL CO. Ltd. 21 April, 1969 [19 Jan., 1968], No. 3069/68. Headings B3B and B3L. A broaching machine for broaching the peripheries of gears or other centrally apertured components comprises a frame 1, 2, a hollow internally toothed broaching tool 40 mounted for vertical machining movement on the frame and work supporting and locating means comprising an elongated work support member 37 which is movable vertically to abut a coaxial locating member 6, means being provided to rotate the work support member 37 to lock it to the locating member with a workpiece 7 clamped therebetween. Vertical movement of the tool 40 is effected by hydraulic cylinder means (not shown) and of the work support member 37 by hydraulic cylinder 10, the piston-rod 13 of which is connected to the member 37. The latter has at its upper end a projecting pin 38 arranged to pass through a workpiece 7 and to enter a complementary bore 8 in the locating member 6, the pin and bore having matching quick-acting threads to provide a locking action upon rotation of the support member 37. Rotation of the member 37 is effected by means of an hydraulic cylinder 25 the piston-rod of which is connected to rack-and-pinion means in a gear case 15 which is adapted to move vertically with the work support 37. During the working stroke of the tool 40 the upper end of its hydraulic cylinder is connected to the lower end of the cylinder 9 in order partially to balance the cutting load thereby relieving the threaded pin 38, 39 of excessive load. |
