DRIVE FOR METAL STRIP PROCESSING MACHINES IN SERIES PARTICULARLY STRIP REELS FOR STRIP PROCESSING UNITS

摘要

1358007 Hydrostatic transmissions I UNGERER 29 June 1972 [22 July 1971] 30470/72 Heading F2D In a hydrostatic transmission wherein a pump 7 and a motor 8 brake a reel 2 and drive a reel 6 respectively, one a winding-up reel and the other a winding-on reel, the pump and motor (of variable displacement) are supplied from a pump 14, which is also of variable displacement in the embodiment shown, through lines 13a and 13 and four-way valves 26 and 27, the pump 7 and motor 8 being in series, and a pump 18 supplies fluid to line 13 to create a tension in the material (e.g. metal strip) being passed between the reels 2, 6. Load regulators 9, 10 and servo valves 11, 12 are provided for the pump 7 and motor 8, and output regulator 15 and servo valve 16 control the pump 14. In an alternative embodiment a further variable displacement pump drives the strip passing between the reels (Figs. 2 and 4, not shown) and the pump 14 is replaced by a constant displacement pump. Two pumps 18 (Fig. 4, not shown) may also be provided feeding to different points of the hydraulic circuit. In each case an electric motor 24 drives all the pumps. The pump(s) 18 also supply make-up fluid to the main circuit. The pump 7 and motor 8 may be driven in reverse by use of valves 26 and 27, and by closing valve 25, pump 7 and motor 8 can be driven in different directions.