Patent GB-873474-A (GB)
Title: Improvements relating to mills for rolling wheels and like blanks
Inventor: KENDALL EDGAR HOMER
IPC: B21H1/04
Filed: 1957-07-23
Abstract: 873,474. Rolling wheels and discs. KENDALL CONTRACTING Inc. July 23, 1957 No. 23225/57. Class 83 (4). A mill for rolling wheel and like blanks comprises two edge rolls of which the axes are divergently related, for working respectively opposed side faces of a blank being rolled, means to urge one of the said rolls forcibly towards and against a corresponding one of the said side faces, and means, responsive to the radial growth of the blank, to control the said urging means during the rolling of the blank. Mounted on parallel tracks 11 and 12 is a frame 13 for an upper edge roll 14 and a lower anvil edge roll 15. On a pair of guide rods 17, 18 extending rearwardly from the frame 13 is a carriage 19, the lower portion 19a of which carries an anvil roll 20 and is moved on the guides by an hydraulic cylinder 23. The upper part 19b is movable longitudinally relatively to the part 19a by hydraulic cylinders 26 and has horizontally pivoted arms 29, 30 which carry guide rolls 21, 22 and which are connected by tie rods 31, 32 to a cross-head 28 of the part 19a. Journalled in side walls 34 of the housing 13 and rotatable by hand wheels 44, 45 are shafts 39, 40 having eccentrics on which are mounted journal housings 41, 42 for the rolls 13, 14 which, as shown in Fig. 3, act on both the web and edges of the wheel 50<SP>1</SP>. The pressure exerted by the anvil roll 20 is opposed by two pressure rolls 51 carried by rods 52 from a cross-bar 53 movable by an hydraulic cylinder 54. Edge roll housing 41 is raised and lowered by mechanism 49, Fig. 5. A member extending upwardly from the housing is coupled to a member 65 from which extend four vertical guide rods 70 while the centre of its upper surface forms a bearing surface for a piston 71 operating in a cylinder 72. Integral trunnions 73 and rods 74 extend laterally from the cylinder and are journalled in annular eccentric rotatable members 76 carrying pinions 78 which may be rotated from a common shaft operated through gearing from a motor 83. The guide rods 70 extend through a pair of U-shaped members 86 secured to the trunnions 73 and are connected in pairs by cross-pieces 87 connected with lifting cylinders 88. During operation the lower edge roll 15 serves as an anvil roll while the upper roll 14 is actuated by the above mechanism to form the wheel as required. Mounted above the ram cylinder 72 is a liquid reservoir 90 communicating with the head end of the cylinder 72 through a dump valve 91 constructed so that during the initial downward movement of roll 14 the ram cylinder is quickly filled by gravity but when the blank is encountered the only fluid admitted to the ram is supplied by a pump 94 under the control of a cylinder 95. The piston-rod 96 of the control cylinder is coupled to a lever 99, which is operated upon by a rod 100 movable with the roll 14 and by a template 107 movable by a rack 109 and pinion 110 which is driven in a manner dependent on the growth of the wheel, e.g. by being coupled to the usual indicator 111 operated in response to movement of the anvil roll 20. Instead of a mechanical control linkage for the pump 94, known forms of hydraulic or electrical control means could be used. The valve 91 comprises a housing 120, Fig. 8, containing a valve piston 121 which in the postion shown allows liquid to pass from the reservoir 90 through passages 122 and 93 to the ram. The valve can be moved to the right by a build-up of pressure in a chamber 130, this being adjustable by means of the knob 134 associated with a check valve 124, after which the ram can receive liquid only from the pump 94 by way of passage 123, check valves 124 and 125 and passages 126, 128, chamber 130 and passage 131. After the movement of the piston 121 to the right, the rolling of the blank starts and proceeds in accordance with the fluid supplied by the pump 94. When roll 14 reaches its lowest position, pressure in the ram cylinder is released and pressure fluid is supplied to the lifting cylinders 88 to retract the roll 14. In order to lower the roll 14 an operator moves the valve member 141 of a four-way valve 142 to the left so that the pump 94, and also a constant delivery pump 144, supply liquid to the port 123 and also to the rod ends of the lifting cylinders 88 while the head ends of the latter are connected to exhaust through a valve 149. As the roll 14 is lowered a crosspiece 87 on one of the pairs of lifting cylinders trips a switch 152 to actuate valve 149 to direct the exhaust from counterbalance valve 150 to counterbalance valve 155 with a higher setting, thus causing a rise of the back pressure in the cylinders. As soon as pressure begins to build up in the fluid circuit the pump 144 is effectively disconnected through a valve 157. To retract the upper edge roll after the rolling is completed, the operator moves the spool 141 of the valve 142 to the right thereby connecting pumps 94 and 144 to the heads of the cylinders 88 and also to the port 135 of the valve 91 to start decompression of the ram cylinder, the rod ends of the cylinders 88 being connected to exhaust. Two alternative forms of fluid circuits for the control of the mill are described with reference to Figs. 10 and 11 (not shown).