GB1440075A - - Google Patents

Abstract

1440075 Hydraulic presses; cutting-out presses SAMCO-STRONG Ltd 22 Aug 1973 [24 Aug 1972 10 July 1973] 39461/72 and 32804/73 Headings B4B and B5F A press, for example a moving bed, receding head, cutting press, comprises a plurality of cylinder units 58 to effect movement of a platen 40, a spool valve 64 associated with each unit, means 80 to move the spools of the valves to control fluid flow into the units, and drive means to move the means 80 simultaneously to actuate the units 58 together and to maintain the platen 40 parallel to the other platen 46. Each unit 58 is fixed to the platen 40 and has piston-rods extending from both sides of the piston and secured to the press frame. Each spool valve may be mounted on its associated unit 58, and the means 80 mounted on side members 76 which can be raised or lowered to produce corresponding movement of the platen 40 by screws 84 or by bell-crank levers (84<SP>1</SP>, Fig. 12, not shown). Alternatively the valves may be fixed to the frame and their actuating means associated with the platen. The upper platen may be driven into a forward operative position on rollers 116 by chains controlled by limit switches MS1-3. A pressure relief valve (arrangement PV10, PV17, Figs. 10, 11, not shown) is arranged upstream of the spool valves and is arranged to operate at a pressure which increases with the highest pressure in any of the units 58 downstream of the spool valves. The stroke of the lower platen is determined by actuation of a micro-switch the position of which may be adjusted as described in Specification 1,342,585. In this present Specification (Figs. 8 and 9, not shown) the switch is mounted on a slide normally positionally held on a rod but releasable for adjustment. The rod is threadedly mounted in a nut for fine adjustment of the switch.