Rolling mill apparatus

Claim 2

Rolling mill apparatus including a pair of roll assemblies (10,12) each constituted by a rotatably mounted support roll (14,16) and a plurality of work rolls (18,20) spaced around said support roll, characterised in that the work rolls are backed by respective cradle elements (22,24), means being provided whereby, as the roll assemblies rotate so that the work rolls and cradle elements orbit the respective axes of the support rolls, each work roll (18,20) and its respective cradle element (22,24) are initially positioned in readiness for a bite by the work roll into a workpiece being fed between the roll assemblies, said work roll and cradle element roll together through an arc of movement in which a bite into the workpiece is taken, and said work roll and cradle element are then caused to precess around the support roll (14,16) to their initial positions relative to said support rolls.

Claim 3

Rolling mill apparatus according to claim 1, further characterised in that the means whereby each work roll (18,20) and its respective cradle element (22,24) are initially positioned in readiness for a bite by the work roll into a workpiece being fed between the roll assemblies (10,12), said work roll and cradle element roll together through an arc of movement in which a bite into the workpiece is taken, and said work roll and cradle element are then caused to precess around the support roll (14,16) to their initial positions relative to said support rolls, are constituted by gear and gear segment drives (48,50) between the support rolls (14,16) and the respective cradle elements (22,24), and by spring return mechanisms (64) whereby the work rolls (18,20) and cradle elements (22,24) are returned to their initial positions relative to their respective support rolls (14,16).

Claim 4

Rolling mill apparatus according to either one of the preceding claims, further characterised in that means are also provided for reducing the rate of orbiting movement of each work roll (18,20) as it reaches the roll bite zone whereby the continued rotation of the respective support roll (14,16) causes the work roll (18,20) and cradle element (22,24) to be rotated in such a way that the workpiece is drawn between the roll assemblies (10,12) and no direct force is required to feed the workpiece between the roll assemblies.

Claim 5

Rolling mill apparatus according to claim 3, further characterised in that the means for reducing the rate of orbiting movement of each work roll (18,20) as it reaches the roll bite zone are constituted by stop mechanism for latching the movement of the respective work rolls (18,20), in turn, to slower moving parts as said work rolls pass through the roll bite zone.

Claim 6

Rolling mill apparatus according to claim 4, further characterised in that the stop mechanism includes pairs of reaction members constituted by further gear pairs (66,66 and 68,68) which flank the roll assemblies (10,12) but which are driven at a somewhat slower speed than said roll assemblies, the reaction members each carrying a plurality of spring loaded stop members (70) associated with respective plungers (72) each of which normally projects laterally from a side surface of the respective reaction member, the pairs of plungers (72,72) at the opposite ends of the roll assemblies (10,12) contacting respective ramps (74) at the commencement of their passage through the roll bite zone which force the respective stop members (70) outwards of the reaction members against the force of their respective springs (76) and into the path of movement of portions of carrier links carrying respective work rolls (18,20) between them, that is to say a pair of synchronised and oppositely rotating work rolls which are about to enter the roll bite zone, the pair of work rolls thus being constrained to move at the speed of movement of the respective pair of reaction members through said roll bit zone.

Claim 7

Rolling mill apparatus according to any one of the preceding claims, further characterised in that the plurality of work rolls (18,20) are capable of adjustment relative to their respective cradle elements (22,24) so that, after a period of use of the apparatus, previously unused segments of the rolls (18,20) can be brought into use.

Claim 8

Rolling mill apparatus according to claim 6, further characterised in that face keys (28) are located in respective cradle extensions (26) so that the work rolls (18,20) can be rotatably adjusted to bring different diametrical end slots (30) formed across the end faces of said rolls into alignment with said keys.

Claim 9

Rolling mill apparatus according to any one of the preceding claims, further characterised in that the cradle elements (22,24) associated with the work rolls (18,20) are located in contact with their respective support rolls (14,16) by respective pairs of carrier links (32,32 - 46,46) which are mounted for limited rotation on cylindrical surfaces of respective shaft extensions (15,15) of the support rolls (14,16).

Claim 10

Rolling mill apparatus according to any one of the preceding claims, further characterised in that the work rolls (18,20) and their respective cradle elements (22,24) are longitudinally located relative to the support rolls (14,16) by means of respective peripheral enlargements (52) which are formed on said cradle elements, the enlargements engaging complementary grooves (54) in the surfaces of the support rolls (14,16).

Claim 11

Rolling mill apparatus according to any one of the preceding claims, further characterised in that idler rolls (108,108) are included to keep the mill under pressure for the instants of time between roll bites by the work rolls (18,20).