GB1345064A - - Google Patents

Abstract

1345064 Filter press BERDICHEVSKY ZAVOD KHIMICHESKOGO MASHINOSTROENIA PROGRESS 29 Oct 1971 50322/71 Heading B1D Filter press plates 1 are clamped together against fixed upper plate 3 by a pair of hinged arms 5 whose central hinges are moved together by hydraulic ram 12, 13 to straighten the arms and thereby raise lower plate 4, and the ram is locked by a second ram 16 inserting wedge 17 into rod aperture 14 when the plates are fully clamped. Clamping is initiated by signal Pyl moving valve 18 rightwards, which delivers fluid to the rod space of cylinder 12, wedge 17 being held down by the constant pressure in the rod space of ram 16. When the plates 1 are fully clamped, cam 22 moves valve 21 which moves valve 19 leftwards, thereby supplying fluid to valve 20 which is itself moved rightwards by the rising pressure in the rod space of cylinder 12. Valve 20 then delivers the fluid from valve 19 to the piston space of ram 16 and raises wedge 17 into aperture 14. Ram 16 and wedge 17 are carried by extension 15 of cylinder 12 and move therewith when ram 12, 13 is operated. To lower the plates 1, signal Py2 moves valve 19 rightwards, and the piston space of ram 16 is thereby connected to return. The force available to lower wedge 17 is greater than that which raises it, the latter depending on the differences between upper and lower areas of the piston. Valve 18 is restored to the position shown by its spring and ram 12, 13 expanded. The press may be as described in Specification 1,080,461