| 摘要 |
A ring rolling machine for cold rolling bearing cages and the like has a working station (32) at which the rolling operation is performed on an annular blank by an annular die (80,82) co-operating with a mandrel (50). The die is held coaxially in a die housing (74) mounted rotatably in one of two through openings (62,64) in a shuttle (42) which is reciprocated between the working station and two alternate transfer stations (28,30) at which the front die insert (82) is ejected with the rolled ring and re-inserted with a fresh blank. The die housing projects through a slot (70) in the shuttle to engage the die drive roll (78), and via the die transmits rotation derived from the drive roll to the mandrel and a pair of mandrel support rolls (110) which apply radial force to the mandrel. The mandrel support rolls are mounted in a head on a shaft pre-tensioned to control their axial position without fasteners; they also control the axial positions of the die and mandrel. |
