Patent GB-340933-A (GB)
Title: Rolling mills and methods
IPC: B21B1/32
Filed: 1929-09-04
Abstract: 340,933. Rolling. BARTEN, E. Buschh³tten. near Siegen, Westphalia, Germany. Sept. 4, 1929, No. 26901. [Class 83 (iv).] Blanks are rolled into sheet or strip metal in a mill having means for gripping the ends of the blank on either side of the mill and maintaining the grip throughout the entire operation, the mill drive being reversed to roll the sheet back and forth. The material is preferably rolled under a tension approaching the elastic limit and this tension may effect the rolling the rolls not being driven. If rolling is commenced with a long thick blank the grippers are not attached during the first few passes, roller tables 16, 17 being then employed to support the work. When the work is sufficiently thin the grippers 9, 10 are attached, being carried by flexible bands on drums 5 having recesses 14 to receive the grippers. When the final reduction has been effected the rolled sheet material is passed to a drum 18 driven by a chain 18<1>, Fig. 2. The bearing 19 swings aside to permit removal of the coiled stock. When driven rolls are employed the drive is from a motor 21 through gearing 25 shaft 27 and reversing train 36, 37 controlled by friction clutches 31, 32 that may be operated by fluid pressure at 34. The shaft 27 also drives the drum 5 through bevel and worm gearing 60, 44, and friction clutches 62, 46. The drum shafts also carry brakes 65, 49. The brakes and clutches are controlled by linkage from treadles 68, 54 so connected that removal of the brake engages the clutch and conversely. The amount of braking is regulated by adjusting the distance apart of the shoes and the slip torgue of the clutches is adjusted by shifting the fulcrum 48<1> of the clutch levers. The brakes and clutches can be variously adjusted, for example the clutch on the leading side of the sheet being rolled may apply a tension just below the elastic limit, the drum tending to wind the stock faster than the rolls deliver, and the brake on the other side of the mill may apply a similar tension. The brake may however be set to apply only sufficient pressure just to keep the sheet taut, and in this case the tension on the leading side may be sufficient to drive the rolls, the clutch D being then in neutral. Various other arrangements may be adopted, the tension in any case being reduced as the sheet becomes thinner. The pass is preferably adjusted as at B whilst the rolls are in operation. Various forms of electromagnetic brakes may replace the friction brakes shown, and such forms may act also as electromagnetic clutches. The working rolls 1, 2 are preferably of small diameter being supported by larger rolls 3, 4. Each working roll may have two supporting rolls. The rolls may be shaped to apply greater pressure at the edges of the sheet. To prevent the strip from deflecting laterally pressure guides such as shown in Fig. 8 may be employed the guides applying pressure to the material at each edge and being gapped in the centre to pass the grippers. The pressure on each edge may be adjusted independently by the gearing shown by declutching the handwheel 91 from the wheel 92. The pressure applying guides may be replaced by staggered rollers similar to those used in straightening machines.