Abstract: A self-cleaning filter with a bypass port is provided for a washing machine that recirculates water back to the wash tub. The filter includes a housing with a filter element disposed therein. The filter element normally filters lint and other material from the water drained from the wash tub, with the water then being recirculated back to the wash tub. When the filter element becomes clogged, the water automatically flows through a bypass port in the filter, such that recirculation continues. The filter element is automatically cleaned by back-washing the filter.

Abstract: A filter housing (14) has a first inlet (16) for receiving a first fluid such as oil from a machine such as an internal combustion engine (12), a first outlet (20) returning the first fluid to the machine, a second inlet (24) selectively receiving a second fluid from a source of cleaning fluid (28), and a second outlet (30) exhausting the second fluid. The filter housing has a first flow path therethrough from the first inlet through a filter element (40) in one direction to the first outlet, and a second flow path therethrough from the second inlet then through the filter element in the opposite direction then to the second outlet. The first and second inlets and the first and second outlets are all provided at the same axial end of the housing, for modularity. First and second common flow channels (58 and 68) in the housing each carry the first and second fluids in opposite directions. First and second valves (84 and 86) in the housing enable switching between filtration and cleaning modes.

Abstract: An apparatus and methods for sanitizing and cleaning filtration systems is provided. The apparatus includes a chamber fluidly connected to a source of fluid for backwashing the system, and a heat exchanger for increasing the temperature of the fluid. A filter media is positioned within the chamber. The method of sanitization involves backwashing the apparatus to remove debris, then continuing to circulate the backwash fluid through the system while increasing the temperature of the fluid, until the temperature of the water and apparatus is sufficient to deactivate microorganisms. The method may also involve increasing the disinfecting power of the fluid by adjusting the pH of the fluid. The apparatus may be provided with a scavenger to assist in the substantially complete removal of fluid from the chamber during and after a steaming or cleaning process.

Abstract: A cap assembly for a vessel having a medial portion and a lower end. The vessel is adapted to contain a filtering medium. The cap assembly is provided with a cap having a lower portion, an upper portion, a sidewall extending between the lower portion and the upper portion, and a fluid outlet being formed through a portion of the sidewall. The lower portion is sized so as to be positioned on the medial portion on the vessel to form a fluid-type relationship between the lower portion of the cap and the medial portion of the vessel when the cap is positioned on the medial portion of the vessel and so that fluid communication is established between the cap and the vessel. The fluid outlet is offset laterally from a centrally disposed elongated axis of the cap so as to form a vortex when back washing the filtering medium.

Abstract: For uniformly, satisfactorily, and automatically removing foreign matter that has accumulated on the filter, the apparatus includes a housing having an inflow portion and an outflow portion, a filter having a large number of piled resilient filter chips between which a filtering gap for passage of fluid to be filtered is formed, an actuator for expanding the filtering gap between spring members in backwashing, and a backwashing channel for causing backwash fluid to flow through the filter.

Abstract: A chemical-mechanical-polishing system having a slurry distribution system, a polisher, a deionized water supply, and a drain, includes a slurry filtration system. The filtration system has two filters for alternately filtering particles in slurry and being backflushed with deionized water. Two input valves have input ports connected to the slurry distribution system and output ports respectively connected to the filters for filtering. Two output valves have input ports respectively connected to the filters for receiving filtered slurry and output ports connected to the polisher. Two backflush valves have input ports connected to the deionized water supply and output ports respectively connected to backflush with deionized water; the output ports are also respectively connected to the input ports of the two output valves. Two drain valves have input ports respectively connected to the filters for receiving backflushed fluid and output ports connected to the drain.

Abstract: A filter cloth comprising at least a base layer and a filtering layer, characterized in that the ratio T/L of the thickness (T) of the filtering layer to the length (L) of fibers of fiber bundles constituting the filtering layer is 0.02 to 0.7 and the sum of a projected area of the fibers onto the base layer surface is 8 to 350 times the area of the base layer surface and, a filter cloth characterized in being constituted with at least a base layer and a filtering layer mainly composed of fiber bundles of crimped fiber ratio over 5%.

Abstract: A manifold system for supplying water to two or more consumer devices on a marine vessel having a primary consumer and one or more secondary consumers has a primary conduit connectable to the primary consumer, the conduit having an interior cross-sectional area determined by water requirements of the primary consumer. A manifold has a threaded inlet fitting, a primary outlet fitting dimensioned to be connectable to the conduit, and a plurality of secondary outlet fittings connectable to secondary conduits for secondary consumers. The inlet and secondary outlet fittings of the manifold have cross-sectional areas determined by dimensions of the primary outlet fitting. A strainer has an inlet connected to a through-hull fitting for receiving and straining incoming raw water and an outlet having a threaded connector for attachment to the manifold inlet fitting, the strainer having a flow capacity determined by the diameter of the strainer outlet.

Abstract: A separator includes a barrier 53 for retaining solid material thereon and an automatic mechanism for alternately preventing and allowing the flow of liquid to the separator outlet. When the flow is prevented, the liquid backs up through the barrier and washes the solids to a solids collection region 55. In one embodiment, the automatic mechanism includes a pivoted flap 101 and, in another embodiment, a siphon.

Abstract: A reciprocating power sprayer for cleaning a rotating cylindrical wastewater screen of the type formed of tubular perforate wedgewire. The spray is reciprocated on an elongated pneumatic cylinder which is arranged in parallelism along the cylinder wastewater screen. Controls are provided for automatically controlling the reciprocation of the spray.

Abstract: A chemical-mechanical-polishing system having a slurry distribution system, a polisher, a deionized water supply, and a drain, includes a slurry filtration system. The filtration system has two filters for alternately filtering particles in slurry and being backflushed with deionized water. Two input valves have input ports connected to the slurry distribution system and output ports respectively connected to the filters for filtering. Two output valves have input ports respectively connected to the filters for receiving filtered slurry and output ports connected to the polisher. Two backflush valves have input ports connected to the deionized water supply and output ports respectively connected to backflush with deionized water; the output ports are also respectively connected to the input ports of the two output valves. Two drain valves have input ports respectively connected to the filters for receiving backflushed fluid and output ports connected to the drain.

Abstract: The filter intercepts dirt emanating from a molten-polymer extruder. The filter is clamped between perforated support plates, and a rotor sweeps the holes in the upstream plate. The rotor defines a cavity which communicates with a small sector of the holes at any one time. The cavity is openable to drain, via a valve. The melt is under high pressure, to which the cavity is exposed. The rotor is rotated by a drive-shaft, and the drain is located co-axially with the drive-shaft.

Abstract: A self-cleaning filter is provided for filtering particulate from a fluid flow stream such as water used in an irrigation system or the like, wherein a segmented filter element is backwashed or flushed clean in response to cyclic on-off supply of fluid. The self-cleaning filter comprises a filter housing having inlet and outlet fittings for in-line connection along a water supply conduit at a location downstream from a system on-off valve. The segmented filter element is supported within the filter housing, with a first filter segment aligned with an inlet port for filtering water. When the water supply is turned on, filtered water passing through the first filter segment initially backwashes through a second filter segment with increasing line pressure to flush prior-collected particulate thereon through a flush port. When the line pressure reaches a predetermined level, a normally open and pressure responsive flush valve closes the flush port.

Abstract: A system for filtering fluids uses the pressure differential across a filter element between an internal filter volume and an external filter volume to control the rate of fluid flow through the filter element. The internal filter volume communicates with a backwash volume contained in the external filter volume. The backwash volume may be movable relative to the filter element to clean accumulated filtrate from the filter element through backwashing. By increasing the pressure in the internal filter volume, the rate of backwashing can be increased while the rate of fluid flow into the internal filter volume is decreased. Particularly when the filter element becomes clogged, damage to a filter caused by an excessive pressure differential across the filter element may be decreased.

Abstract: A filtration unit is provided with a self-cleaning mechanism which backflushes a screening element therein when it becomes blinded by solid material. A reservoir enables a head of screened liquid to be built up above the screening element. Upon blinding of the screening element, a subsequent rise in the pressure at the inlet of the filtration unit is detected by way of a rising fluid level in a vertically extending chamber. The above causes the opening of a discharge valve which enables a discharge flow to rapidly empty the reservoir through the screening element in a reverse direction, thereby clearing the screen. The clearing operation is carried out entirely hydraulically by the action of the screened fluid and thus no brushes, rakes or scraping devices are required.

Abstract: An apparatus for treatment of water for consumption comprises a main storage tank, a pump, a treatment reactor and a valve for controlling the flow of water from the inlet pump to the treatment reactor and from the reactor to a flush discharge and to a waste water discharge. The tank is basically cylindrical with two part cylindrical recesses parallel to the axis of the tank and lying along one side of the tank. Each recess receives a respective one of the cylindrical pump body and the cylindrical reactor body. The pump and reactor are therefore efficiently stored within the cylindrical surface of the main tank.

Abstract: A method of purifying impure water to provide drinking water using an apparatus, the method comprising the steps of providing a microfiltration unit, a reverse osmosis unit and a CIP (clean-in-place) tank containing retentate interconnected to permit backflushing the microfiltration filter with retentate and continued or uninterrupted operation of the reverse osmosis unit by directing retentate thereto.

Abstract: A cleaning apparatus for a magnet filter and a method of cleaning a magnetic filter. The magnetic filter is disposed in a circular passage for processing a cleaning fluid. The cleaning apparatus includes sensors for determining when the magnetic filter should be cleaned, which prevents a loss of effectiveness of the cleaning fluid due to detached metal powder falling off of the filter.

Abstract: A method and apparatus for determining the fouling effect of a feedstream on a filter having known characteristics disclosed. The method comprises passing the feedstream through a filter (5) having known characteristics; determining the change in resistance to flow of the feedstream across the filter, either continuously or over a number of time intervals and from this data, calculating a feed fouling index (FFI) representative of the fouling characteristics of the feedstream with respect to the filter. A method and apparatus for monitoring the operation of a filtration system is also disclosed the method comprising sampling system parameter values at selected locations within the filtration system at a predetermined sampling rate; generating a parameter profile characteristic from the sampled parameter values at predetermined intervals of time; and analysing the parameter profile characteristic to determine correct operation of the filtration system.

Abstract: A liquid filtering apparatus which reduces or eliminates the need for regular manual cleaning or backwashing. Backwashing of the filter occurs automatically in response to sensed conditions of filtering. The filtering apparatus includes a chamber, and a filter element in the chamber, a valve for directing liquid through the filtering element in a first direction to filter the liquid. The valve reverses the direction of liquid flow through the filtering element when excessive resistance to flow through the filter element occurs.

Abstract: The installation disclosed comprises a body of water, a pump, a filter and pipes connecting the body of water, pump and filter. Additional pipes lead from the pipe to the return pipe and to waste. Solenoid operated valves are provided in the pipes so that flow through these pipes can be permitted or prevented depending on whether the valves are open or closed. A pressure sensor detects pressure at the inlet of the filter. A programmable controller controls operation of the valves all of which can be operated independently of the others. The body of water will normally be a swimming pool but could be a tank in which aquatic creatures are grown.

Abstract: A self-gush-cleaning filter device comprises a filter casing (1) provided with an inlet passage (a) and an outlet passage (d), a screen (11) disposed within the filter casing (1) so as to slide along the inner surface of the filter casing (1) in the flowing direction of a fluid, a foreign matter ejecting opening (15) being formed between the screen (11) and the inlet passage (a). A drive shaft (4) for driving the screen (11), a screen driving unit (3) for driving the drive shaft (4) so as to move the screen (11) quickly in a downstream direction in which the fluid flows from the inlet passage (a) toward the outlet passage (d) and to move the screen slowly in an upstream direction. An outlet shutoff valve (14) is disposed in the outlet passage (d) of the filter casing (1). The screen driving unit (3) is actuated after closing the outlet shutoff valve (14) to move the screen (11).

Abstract: The apparatus treats storm water and includes a cylindrical basket that has a housing with a circumferentially extending air slot near the base of the housing. The basket contains an annular bed of absorbent material surrounded by a filter cartridge. Water flows radially inward through the filter and the bed into a cylindrical inner drainage space which has an outlet at its lower end, covered by a float valve. The drainage space is also in fluid communication with a one-way valve that allows air to pass from the housing into the environment. During operation, the float valve lifts when the water level rises and air is expelled from the drainage space through the one-way valve. As a result, water is continuously siphoned through the basket apparatus. When the water level drops, air enters through the air inlet slot of the housing and rises in turbulent fashion along the filter, scouring the filter and dislodging particulates.

Abstract: A differential pressure monitor measures the pressure at a plurality of heights in a filter bed. A preferred embodiment of the monitor comprises an elongated body, a plurality of pressure sensors located on the elongated body for obtaining the pressure readings, a control means for determining differential pressures from the pressure readings, each differential pressure being the difference in pressure between pressures measured at two different heights in the filter bed, and transmission means to transmit the pressure readings from the pressure sensors to the control means. Methods of monitoring and controlling the performance of a filter bed during filtration and during backwashing also are provided. Two such methods include measuring turbidity levels in a filter bed and obtaining water samples from a filter bed.

Abstract: The invention is directed to an apparatus for processing rain and/or surface water having a container for storing the water to be processed, a circulating arrangement for circulating the water to be processed in the container, a measuring arrangement for measuring the water quality of the water to be processed, and a processing arrangement for treating the water to be processed in dependence upon the water quality measured by the measuring arrangement.

Abstract: A method for withdrawing priming fluid from the extracorporeal circuit of a dialysis machine is described which substantially prevents return of the priming fluid back to the patient. In accordance with the method, priming fluid is drawn from the extracorporeal circuit through the dialyzer membrane and into the dialysate circuit. Blood is introduced into the extracorporeal circuit as the priming fluid is withdrawn through the dialyzer. Withdrawal of the priming fluid may be accomplished by pumping the blood pump in the forward direction at a first rate and operating a pump in the dialysate circuit at a second rate. Valves in the dialysate circuit are operated such that the pump in the dialysate circuit draws priming fluid across the dialyzer membrane into the dialysate circuit, and thereby prevents the priming fluid from being returned to the patient.

Abstract: In a filter changing device with a flow path for the plastic in which one two or more filters can be inserted into the flow path as desired, the invention proposes to fit the filter support in such a way that it can assume a working back rinse and filter change position, in which, in the back rinse position, the plastic is caused to reverse its direction of flow through two interconnected flow channels without permitting air to penetrate into the filter changing device and in which there is free access to one of the filters in the filter changing positions. As the back rinse position can succeed a filter changing position, it is possible to clear the whole filter changing device of occluded air before a plastic processing plant starts production.

Abstract: A filtering apparatus is provided wherein the filter can be backwashed by an explosive-like surge of backwashing fluid. The backwashing assembly includes a quick-opening backwash valve which is not actuated by a linearly-acting valve stem disposed on the outlet side of the valve. In a typical embodiment, the inlet valve to the filtering apparatus is a rotating butterfly valve and the backwash valve is physically attached to the inlet valve, such that, when the inlet valve is open, the backwash valve is fully-closed and when the inlet valve is moved towards its fully-closed position, the backwash valve is fully-opened. The invention uses a two-step method of initially applying biasing pressure on the inlet valve/backwash valve combination and to thereafter provide additional pressure to dislodge the backwash valve from the valve seat--whereupon the backwash valve quickly opens and an explosive-like surge of backwashing fluid effectively backwashes the filtering media.

Abstract: A liquid cleaning system, which includes a barrier type filter having a back-flush arrangement for recovering filter contaminants from the back-flushed liquid which is available only at a low, not necessarily consistent, rate, includes a fluid-powered centrifugal cleaner which, in addition to the normal shaft-mounted rotor through which liquid is passed to separate contaminants centrifugally due to rotor speed, includes fluid drive means in the form of fluid reaction drive nozzles supplied with pumped liquid from the system as a drive fluid to rotate the rotor at a speed above the minimum to effect centrifugal separation of the contaminants from the back-flushed liquid in the rotor and accumulation of the outlet of the rotor. The spent drive fluid mixes with the cleaned back-flushed liquid in a discharge region and both may be re-used in the system.

Abstract: A self-purifying filter apparatus comprising (1) a filter having a first surface and a second surface; (2) flow control means, such as a vacuum pump, for causing a stream of fluid interspersed with solid particulates to pass from the first surface to the second surface through the filter, thereby removing some of the solid particulates from the first stream of fluid and depositing them on the first surface; and (3) a purging device, such as a small reservoir of water (potentially formed, in part, by water previously filtered by the filter), for causing a second stream of fluid to pass from the second surface to the first surface through the filter without substantially changing the position of the filter, thereby rinsing and removing from the first surface at least some of the solid particulates that were deposited there.

Abstract: An apparatus is disclosed for salvaging a patient's own blood during intraoperative surgical procedures and reinfusing the blood, washed and filtered, to the patient substantially continuously, on-line and in real-time. The apparatus comprises suction means, admixing means for admixing aspirated blood with a washing fluid, filtering means for filtering the admixture through an emboli filter, monitoring means for measuring the amount of cellular component volume in the aspirated, filtered blood, filtration means for removing excess fluid and impurities from the blood, and reinfusion means for introducing the washed and filtered blood to the patient free of emboli. The apparatus is structured to introduce washing fluid to the aspirated blood in proportion to the measured hematocrit level of the blood that is aspirated. Methods are disclosed for priming of the system, cleaning and flushing the apparatus of blood clots and debris by means of reverse filtration and filtration of blood for reinfusion.

Abstract: This invention comprises a process and apparatus for producing purified drinking water from surface or ground fresh water sources using no chemical pretreatment or coagulants, by usage of a positively-charged filtration media to attract the typically negatively-charged suspended solids present in the water source. The process, which can be portable, includes a filtration system having a filtration/recirulcation/backwash component and a disinfection step. The process further includes a system controller which receives electrical signals from float controls to control the filtration, recirculation, and backwash steps. This process produces drinking water which meets or exceeds the guidelines set by the World Health Organization for turbidity and microbiological content.

Abstract: A filtering assembly for separating solids suspended in a solution includes a control device closing a plurality of supply devices for the solution to be filtered and for washing liquid and opening a drain valve of an outlet of the assembly in response to a critical level of accumulation of solids on a pulp detector.

Abstract: Disclosed is a system for processing relatively small volumes of waste water such as that found in residential home use. The system first comprises a chamber adapted to hold the waste water. The system further comprises a first filter adapted to remove course material from the waste water and a second filter adapted to remove fine materials from the waste water. The system further comprises a disinfectant chamber adapted to disinfect the waste water. The system comprises a pump adapted to pump the waste water from the chamber through the first and second filters, and the disinfectant chamber.

Abstract: A monitoring device for a drinking water purification system comprising a microprocessor that controls the overall operations of the monitoring system, a LCD indicating circuit that relates information to maintenance personnel, a detecting means that analyses related data for determining the condition and extents of clogging of the filtration elements, a warning means that produces verbal or musical sound for warning consumers about the clogged condition of the water filtration elements, and a power switching means that cuts off electricity supply to the water pump of the purification system. In operation, the filtration elements will be clogged by impurities after being used for a period of time. If the filtration elements are clogged, the monitoring device will make a sound to warn of such condition of the filtration elements and will eventually cut off the power supply to the pump for stopping water delivery if the clogged filtration elements are not replaced after a certain period of time.

Abstract: A hemodialysis machine is described that has an extracorporeal circuit that is primed automatically prior to connection of the patient to the machine. The priming is accomplished by filling the extracorporeal circuit with a priming fluid, such as a saline or dialysate solution or blood. The blood pump and clamps in the arterial and venous lines are operated by a control system in a fashion to create multiple brief pressure pulses in the priming fluid. The pressure pulses shear air bubbles present on the blood side of the dialyzer membrane off the membrane. The blood pump is then operated to clear the bubbles from the dialyzer compartment where they are removed from the priming fluid by conventional bubble trap apparatus.

Abstract: The present invention relates to a filter unit, and a filtering system using the filter unit. The filter unit includes a housing having a longitudinal axis and an inlet and outlet for fluid containing solid contaminants and a back-flush inlet and back-flush outlet for cleansing fluid. This housing contains a substantially cylindrical filter element which has a longitudinal axis coincident with the longitudinal axis of the housing. The filter element has disposed within it a conduit, adapted to be opened to atmospheric discharge, having a longitudinal axis coincident with the longitudinal axis of the filter element. The conduit also has disposed along its surface cleansing members, which extend from the conduit to the filter element and have apertures to allow the cleansing fluid to flow through the members and into the conduit.

Abstract: The piston arrangement includes one or more pistons, each propelled by a pneumatic actuator. Alternately, an accumulator-type actuator may be used, wherein compressed gas is inputted directly into the backflushing fluid chamber to reverse fluid flow through the filter arrangement.

Abstract: A filter assembly has a cylindrical filter element immersed in the fluid to be filtered, and which fluid normally flows radially inwards through the filter element and is thereby filtered. When the filter element is to be cleaned by backflushing, fluid flowing inwardly through the filter element is impelled by a rotating pump vane which directs fluid within the filter element outwardly at relatively high through the filter element thereby dislodging debris which may have adhered to the exterior of the filter element.

Abstract: Rolling solutions used in cold rolling are pressurized and filtered at working temperature using a filter of the scanning flush type in which flushing nozzles exhausting to a low pressure zone are scanned over an upstream surface of the filtration medium during flushing cycles triggered by a pressure drop across the filter exceeding a predetermined level. Flushing retentate exhausted during the flushing cycles is treated in a secondary filter. Harmful particulates can be removed without retaining wanted components of the rolling solution.

Abstract: Apparatus for treating a liquid containing suspended solids comprising a clarifying vessel and a number of filters positioned around the periphery of the clarifying vessel for receiving and filtering liquid from the clarifier. A filter may be backwashed by isolating that filter, filling the other filter cells with clarified liquid and draining them into the isolated cell to remove filter media contaminants.

Abstract: A water filter having a strainer mounted on the inside for straining water, and a reciprocating device controlled by a pressure differential controller to reciprocate a disk-like scraper in the strainer, causing it to scrape out dirt from the strainer, the disk-like scraper having a center water hole and a check valve mounted in the center water hole for permitting water to flow downwards in the strainer through the center water hole and stopping water from flowing upwards in the strainer through the center water hole.

Abstract: An apparatus for treatment of water for consumption comprises a main storage tank, a pump, a treatment reactor and a valve for controlling the flow of water from the inlet pump to the treatment reactor and from the reactor to a flush discharge and to a waste water discharge. The tank is basically cylindrical with two part cylindrical recesses parallel to the axis of the tank and lying along one side of the tank. Each recess receives a respective one of the cylindrical pump body and the cylindrical reactor body. The pump and reactor are therefore efficiently stored within the cylindrical surface of the main tank. The valve provides five positions including a central closed position, two flush positions and two processing positions. These five positions are arranged by axial movement of a valve member along a cylindrical bore of the valve body.

Abstract: A backwash sealing shoe is provided for a filtration system including a tank having an undivided filtration bed and a plurality of side-by-side headers within the bed, each header in communication with a respective port in a wall of the tank. The sealing shoe includes a hydraulic section including an opening surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one of the ports; and at least one blocking section adjacent the hydraulic section on one side thereof and including a plate surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one adjacent port to thereby block flow from the tank through at least one adjacent port during a backwash operation.

Abstract: A flotation/entrainment reactor is poured with a plurality of concentric tubes forming respective chambers, the tubewear for receiving and filtering a liquid from solids contained therein, and with an inlet cylindrical base receiving the liquid and guiding it and, a rising flow along a cone wall of a frustoconical cap mounted on the base to the region of formation of a foam column in one of the concentric tubes encompassing an imaginary apex of the cone wall of the cap.

Abstract: Electro-magnetic filter apparatus and method of operating to separate and remove oily magnetic solids from wastewaters. The filter apparatus includes a filter assembly having an electro-magnetic coil that encircles a canister. The canister has an interior space defined by a wall surface and a first perforated baffle spaced apart from a second perforated baffle. The interior space contains a ferromagnetic matrix comprising split ring lock washers. The feed side end portion of the canister communicates with the wastewater source that contains the oily magnetic solids, a wash-water supply, a pressurized air supply and a disposal stream. The discharge side end portion of the canister communicates with a recycling stream, the disposal stream and the wash-water supply.

Abstract: A filter flushing arrangement is provided and includes a first filtering device, a second filtering device, and a valve arrangement connected to the first and second filtering devices. The valve arrangement is operative to change the direction of fluid flow through the first filtering device upon a filter element therein becoming clogged to flush the particles to the second filtering device which collects the particles on a filtering element therein and subsequently allows the foreign particles to freely settle to a collection basin. Some form of vibration and/or a burst of fluid from a fluid accumulating mechanism may be used to free the particles therefrom and allow them to settle to the collection basin. The collection basin is capable of collecting the particles over a long period of operation of the fluid system.

Abstract: A control system for controlling a backwash operation in normal and high flow operating modes is provided in a traveling bridge filter having a filter basin; a filter media bed; a filtrate channel; a traveling bridge adapted to traverse the filter basin with a backwash hood suspended therefrom; a programmable logic controller; a reference sensor and five spaced water level sensors. The controller and the sensors control the backwash operation by sensor functions which differ between the normal and high flow operating modes.

Abstract: A hydraulic circuit includes a fluid pressure inlet line (1); a fluid pressure delivery line (2); and a filter unit (FU) interposed between the inlet line (1) and the delivery line (2), with the circuit incorporating an automatic back flushing facility. The latter comprises a valve arrangement A, B, C, D, capable of temporarily preventing initial flow of fluid through the filter unit (FU) in a delivery direction, causing reverse fluid flow through the filter unit (FU) in a back flushing direction, for a predetermined period, with the flushing sequence initiated by the valve arrangement sensing a flow of fluid, at a predetermined pressure, and after the predetermined period, causing fluid flow in the normal delivery direction.

Abstract: A swimming pool control system automatically controls the daily maintenance functions of a swimming pool. The control system actively monitors system conditions, makes adjustments for abnormal conditions, and provides remote feedback of system problems during its daily cycle. In addition, the control system provides operator assisted manual override operation and control of additional auxiliary equipment. The system includes a novel filter valve, a novel water level system and a novel suction valve that can be run and monitored non-manually by a digital controller.