Patent GB-1041480-A (GB)
Title: Automatic gear burnishing fixture
IPC: B24B39/00
Filed: 1964-12-01
Abstract: 1,041,480. Gear-finishing; machine tool details. NATIONAL BROACH & MACHINE CO. Dec. 1, 1964 [Jan. 6, 1964], No. 48733/64. Headings B3B and B3K. A gear burnisher comprises means for driving one of a pair of supports for burnisher gears 26, 28 on a frame 12, a third support for a burnisher gear 49 on a slide 50 movable towards and away from the pair of supports, feed means 14 for feeding a work gear G laterally into mesh with the burnisher gears on the pair of supports, and a pressure device 62 connected to the slide 50 to move it towards and away from the pair of supports to move the burnisher gear on the third support into mesh with the work gear in mesh with the burnisher gears 26, 28 and to apply pressure thereto while the work gear is driven in rotation by the burnisher gear on the driven one of the supports. The burnisher has a base 10 from which extends a vertical plate 12 on which are mounted at fixed locations the supports for the burnisher gears 26, 28. Gear 26 is secured to a shaft 36, Fig. 2 (not shown) which is mounted in the plate 12 and a plate spaced therefrom by a block and is connected by a torsion release drive member 38, Fig. 4 (not shown), to the output shaft 40 of a speed reducer 42 driven by a motor 44. Gear 28 is mounted on a shaft rotatable in a block secured to the plate 12. The third burnisher gear 50 is mounted in the slide 50 which is vertically guided by gibs 51 on the plate 12 and is connected to the rod 60 of the pressure device 62, the operation of which is controlled by a limit switch 64 actuated by an abutment 68 carried by the rod 70. The slide 50 also carries a brake element 72 which is urged downwardly into engagement with the third burnisher gear 49 by a spring 80 except when an abutment carried by the slide engages a gib 51 at the lower part of the movement of the elide. The brake element also has a finger 81 which prevents a succeeding gear to be burnished and carried by an inlet shoot 14 from engaging the burnisher gears and work gear being burnished, the shoot having a release element 16 connected by a crank 18 to the rod 20 of a pressure device 22 for successively releasing gears G to be burnished; a proximity switch 24 stops the operation of the machine in the absence of a work gear in the shoot. In operation, the slide 50 is initially in its upper position and the release element 16 is operated so that a gear rolls into mesh with the burnisher gears 26, 28 and is rotated by the burnisher gear 26 which is continuously rotated. The device 62 is then operated to lower the slide 50, the burnisher gear being held against rotation by the brake element until it meshes with the work gear; if the gear 49 engages the work gear crest-to-crest, the brake element acts to hold the gear 49 until it can engage the work gear correctly. If the driven gear 26 has its rotation opposed, the release drive member 38 will permit relative rotation between the output shaft 40 and the drive shaft 36. After a period of time for burnishing in which the device 62 urges the gears together, the pressure in the device 62 is released but not reversed to relieve the burnishing pressure and pressure is supplied to a cylinder 104 to move an extractor lever 98 having arms which embrace the burnished work gear and are provided with hardened inserts for engaging the gear, the movement of the lever moving the gear axially on to a tray 118 leading to the input shoot 120 of a gear checking machine 122, 124. The operation of the motor 104 is controlled by limit switches 114, 116 actuated by abutments carried by the lever 98. Thereafter the slide is raised to permit the next work gear, which has been released by the element 16 and is retained by the finger 81, to roll on to the burnisher gears 26, 28 for the next burnishing operation.