Abstract: A filtration method includes steps of feeding liquid to be filtered into a filter medium between a fixed plate and a movable plate; and reducing capacity of a filter chamber formed by the medium by moving the movable plate in a direction in which the movable plate presses the fixed plate through the medium so as to perform expressing filtration of the liquid and to produce cake. The reducing step comprises alternately repeating at least one time an expressing pressure-increasing process for increasing pressure in the liquid in the medium by a specified increment in the filtration of the liquid, and an expressing pressure-maintaining process for maintaining the pressure constant during a specified period, so that the filtration is performed under a specified pressure corresponding to a desired water content of the cake to produce the cake. A filter press for employing the method has the filter medium arranged between the fixed plate and the movable plate capable of moving toward and away from the fixed plate.

Abstract: The invention relates to an improvement of the construction of filter plates which are mounted on a filter press. The filter plates comprises a frame (1), a flat filtrate drainage guide member (3, 41, 52) disposed in the frame (1), and a supporting member (5, 5d, 40, 48, 53) for movably supporting the filtrate drainage guide member in the frame (1). The filtrate drainage guide member (3, 41, 52) can be prevented from being broken if filtration pressure applied to one face of the filtrate drainage guide member (3, 41, 52) of the filter plate (2) is much different from that applied to the other face of the filtrate drainage guide member (3, 41, 52) because the filtrate drainage guide member (3, 41, 52) is movably provided in the frame (1).

Abstract: A filter press equipped with a filter cloth hanging rod detecting arrangement which includes a support beam which is so arranged between the front and rear stands and above the hanging rods as to suspend the shatter members by means of corresponding brackets. The brackets respectively have longitudinal apertures extending vertically or shafts extending horizontally. Meanwhile the shatter members respectively have shafts inserted in the longitudinal apertures of the brackets or apertures in which the shafts of the brackets are inserted. Accordingly the shatter members may move upwardly and downwardly according the vertical movement of the hanging rods and also swing in an imaginary vertical plane parallel to the support beam following to the horizontal movement of the hanging rods.

Abstract: A filter cloth hanging apparatus for a filter press, including a set of first and second support arms attached pivotally to each side face of each of filter plates, a spring attached to each of the first and second support arms, a set of first and second horizontal rods extending between opposite side faces of each of the filter plates through the springs, and a filter cloth attached, at its opposite ends, to the first and second horizontal rods and brought into contact, at its central portion, with a bottom face of each of the filter plates such that the first and second support arms are pivotally coupled with each other between each pair of adjacent ones of the filter plates.

Abstract: A washing apparatus for filter presses which is used for washing filter cloths on filter plates upon completion of filtration comprises a carriage disposed above the filter plates, a pantograph attached to the carriage, a fluid cylinder having its rod connected to the intermediate pivot of the pantograph, a washing liquid spraying pipe connected to the lower link overlap region of the pantograph and having nozzles, multiple extensible pipes disposed between the carriage and opposite sides of the pantograph attaching region of the washing liquid spraying pipe for holding the washing liquid spraying pipe horizontal, and a flexible conduit connected to the washing liquid spraying pipe and adapted to move to follow the expansion and contraction of the pantograph.

Abstract: A filter press including a plurality of filter plates, a pair of filter cloths disposed at opposite faces of each of the filter plates, a wind-up device for winding up the pair of the filter cloths, a guide member having a pair of curved guide surfaces formed at its opposite side edges, respectively and a pair of guide rollers. The pair of the filter cloths are guided downwardly by the guide member and the pair of the guide rollers so as to be wound up by the wind-up device such that the pair of the filter cloths are bent inwardly toward each other at the pair of the curved guide surfaces of the guide member, respectively.

Abstract: A filter cloth oscillating apparatus for a filter press wherein the filter cloth generally suspended over springs from a filter cloth hanging rod extending laterally perpendicular to the direction in which filter plates are opened to oscillate the rod and cloth to shake off and filter cake adhering thereto has a drive unit and crank mechanism mounted on a moving bed for moving the upper portion of a filter press horizontally, an oscillating head and actuator therefor, and by means of a plurality of guide members for oscillating the head vertically as well as horizontally. The oscillating head is lowered and raised pneumatically so that in the covered position it can engage with and oscillate the filter cloth hanging rod.

Abstract: A cleaning device for a filter press wherein a spray tube for cleaning filter cloths of the filter press is moved in alternate directions during cleaning in a vertically downward position depending from a second carrier movably supported on a first carrier and cleaning liquor is sprayed through spray nozzles provided in the spray tube. When a cleaning cycle is completed, the spray tube is returned by a rack rod and pinion to a slanted waiting position above the filter plates.

Abstract: A filter cloth arrangement for use in a fixed filter cloth type filter press including at least one pair of first and second filter plates and a pair of first and second filter cloths interposed between the first and second filter plates. The arrangement includes a support member for supporting upper ends of the first and second filter cloths, an elastic member for vibratingly supporting the support member, a fixing member for fixing lower ends of the first and second filter cloths to it, and a first slurry feeding plate attached to the first filter cloth.

Abstract: A slurry feeding device for use in a filter press including at least one pair of first and second filter plates formed with first and second slurry holes, respectively, and a pair of first and second filter cloths interposed between the first and second filter plates. The device includes a pair of first and second plate members formed with first and second through-holes, respectively, and a plurality of first and second fastening members by which the first and second filter cloths are, respectively, secured to the first and second plate members.

Abstract: A filter press separates a raw liquid into a filtrate and a filter residue. The filter press includes a plurality of filter residue separating members each composed of a pair of confronting members between which a slit passage for passing a filter cloth is formed, and each provided between a pair of spaced support frames fixed to a lower portion of each filter plate, while a wedge-like edge portion is formed at the upper edge of one of the confronting members of the filter residue separating member for smoothly separating the filter residue from the filter cloth without any damage to the surface of the filter cloth.

Abstract: An expressing plate assembly for an expression type filter press, wherein openings in the four corners of elastic expressing sheets placed on the opposite surfaces of a core plate are aligned with openings in the four corners of the core plate and in such condition the expressing sheets are secured to the core plate. Seating recesses in the form of circles concentric with the above-mentioned openings are formed in the opposite surfaces of the core plate, while raised portions adapted to tightly fit in the recesses are formed on the expressing sheets. Clamping seating rings are fitted in recesses on the outer side of the recesses. Each clamping seating ring is formed with grooves for filtrate.

Abstract: The upper ends of filter cloths attached to two adjacent filter plates are connected to a filter medium hanger suspended from suspension arms pivotally mounted on one of the filter plates in the upper regions on opposite sides thereof. Arm rests for supporting the suspension arms are provided on the other filter plate in the upper regions on opposite sides thereof. When the filter plates are moved from their closed state for filtration to their opened state upon completion of filtration, the suspension arms, tilting as supported by the arm rests, are caused to vibrate, thereby accelerating the stripping of the cake which has accumulated on the filter cloths connected to the filter medium hanger.

Abstract: 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 having a central opening larger than a slurry feed port and a filter compression diaphragm in the form of two flexible fluid-tight sheets applied to the front and rear surfaces of the base plate and having uneven filter surfaces with a filter cloth piece applied thereto. The diaphragm is integrally formed with a cylindrical portion interconnecting the sheets and extending through the opening in the base plate to define the slurry feed port. A pressure chamber is formed between the base plate and each of the sheets. The compression filter plate has a pressure fluid feed channel communicating at least with the pressure chamber and a filtrate outlet channel open to its filter surface.

Abstract: A reinforcing patch plate comprises a boss portion adapted to be fitted in a liquid passage hole, such as one for filtrate or wash liquor, which is open to a filter surface of a filter-surfaced expressing sheet, a liquid guiding flange portion integrally formed on one end of the boss portion to cover the portion of the expressing sheet around the liquid passage hole, and a core embedded therein to serve as an intermediate layer. The liquid guiding flange is provided on its face with liquid guiding outlet grooves which establish communication between the boss portion and the filtrate grooves of the filter surface of the expressing sheet. The liquid guide grooves are each defined between adjacent ridges arranged side by side on the flange portion and removably attached to the latter.

Abstract: An expressing plate comprises a core plate, a pair of flexible fluid-tight sheets applied to the front and back of the core plate and cylindrically connected together at the central prefilt passage bore of the core plate to define a prefilt passage throughgoing bore, an annular body fitted between the core plate throughgoing bore and cylindrical portion of the sheets, and annular body slipping-off preventing members applied to the front and back of the fitting boundary region between the annular body and the core plate to extend over both the core plate and annular body. The slipping-off preventing members are fixed to at least either the core plate or the annular body.

Abstract: An apparatus comprising a pair of reciprocally movable carriers each provided with a drive dog and a stop dog tiltably pivoted to the carrier and biased toward a tilted position in the direction opposite to a direction of transport of filter plates, a stopper for preventing the drive dog positioned toward the opposite direction from tilting toward that direction and releasing the drive dog from its prevented position, another stopper for preventing the stop dog from tilting toward the transport direction, and a freely movable member pushable by the drive dog to raise the stop dog when the drive dog tilts toward the transport direction.

Abstract: A washing apparatus for a filter press comprises a spray pipe having a number of nozzles and disposed outside of the filter plates so as to extend parallel to one side of such filter plate, a movable unit in which one end of the spray pipe opposed to a lower corner of such filter plate is pivotally mounted and which is movable in a region outside of the filter plates parallelly to the latter, a carriage supporting the movable unit and movable in a region outside of the filter plates in the direction of movement of the latter, which carriage, each time a filter plate is transferred toward a movable end plate, serves to carry the movable unit in a direction opposite to the direction of such transfer so as to position the spray pipe between separated filter plates, a mechanism for moving the movable unit to and fro when the spray pipe is positioned between separated filter plates, and a second mechanism for raising and lowering the spray pipe synchronously with the to-and-fro movement of the movable unit, these

Abstract: An expressing filter plate comprising a base plate and a diaphragm sheet covering the base plate and having a filter surface, with a pressure fluid chamber formed between the base plate and the diaphragm sheet. The diaphragm sheet is formed, in its peripheral portion to be clamped between pressed filter plates, with a fluid passing opening in communication with a fluid passage in the base plate. A covering member having a tubular portion fitting in the opening is made of a material having higher hardness than the diaphragm sheet. The covering member has a flange portion formed with fluid grooves for maintaining the tubular portion in communication with filtrate grooves in the filter surface of the diaphragm sheet.