Image Number 5 for United States Patent #4317734.
A filtration-compression type filter press comprising a fixed end plate and a movable end plate and compression filter plates suitably disposed therebetween. Each compression filter plate comprises a base plate two flexible fluid-tight sheets applied to the front and rear surfaces of the base plate respectively and having uneven filter surfaces with a filter cloth piece applied thereto to define pressure chamber between the base plate and each of the sheets and to provide a filtration chamber between adjacent filter plates for receiving a prefilt. The compression filter plate has a pressure fluid feed channel communicating with the pressure chamber a filtrate outlet channel open to its filter surface, and a prefilt supply channel open to the filtration chamber. The filter plate is further provided with another pressure fluid feed channel open to its filter surface and having a bypass channel in communication with the first-mentioned pressure fluid feed channel and a pressure fluid feed line and a branch line are provided with valves.