GB130341A - Improvements in or relating to Machines for Forming Rings having a Profiled Inner Surface. - Google Patents

Abstract

130,341. Aktiebolaget Svenska Kullagerfabriken. July 26, 1918, [Convention date]. Forging-machines; dies; mandrels.-A machine for making outer track rings for ball-bearings &c. by upsetting tubular blanks while held in a die. has a collapsible mandrel with two sets of jaws 1,2 relatively movable axially. The jaws 1 are pivoted to a rod 7 secured to a disk 8 and are arranged between the jaws 2. These are pivoted to a sleeve 15 raised by a spring 16 to project them as shown in Fig. 2, so that the blank can be placed around them. The upper die, Fig. 1, comprises a spring mounted wedge-block 27 to expand the jaws 1, 2 to the correct size and an upsetting sleeve 25. As this is brought down the blank placed around the projecting jaws 2, Fig. 2, the sleeve 3 and the jaws 2 are forced into the die 4 as shown in Fig. 3, until the sleeve 15 engages the tubular stop 17 supported by the disk 8, the spring 16 being compressed. Further movement causes the sleeve 25 to upset the upper edge of the blank, the spring 28 being compressed. At this stage the upper die holder 24 engages the die 4 so that further movement presses this down against the action of stronger springs 12 acting through a disk 11 and rods 20 and as this disk 11 also carries the disk 8 by means of the sleeve 9 the jaws 1, 2 move down with the die 4 and sleeve 25. The sleeve 3 however remains fixed as it engages the holder 5 and it thus upsets the lower edge of the blank. When the upper die is withdrawn the parts should resume the positions shown in Fig. 2, the jaws being free to move inwards to allow the removal of the ring. If the work sticks in the die 4, a blow on the-projection 33 will act through rods 31 and the sleeve 17 to force the jaws 2 and work out.