Abstract: A filter apparatus includes a endless filter belt loop disposed in an interior space within a tank which receives liquid to be filtered. The filter belt has a series of closely spaced parallel guide-flight bars attached which are successively engaged by an extendible element on a pivot plate which is periodically oscillated to under the filter belt. The bars are received in guide spaces to hold the filter belt in position over a filter support having openings allowing filtering flow thererthrough. Collapsible sealed hoses partially filled with liquid are used as edge seals extending along the guide spaces over side edges of the filter belt and are expanded by engagement of an upper end of each of the hoses with a squeeze member on the pivot plate. The squeeze members are moved off the hoses when the pivot plate is oscillated to advance the filter belt during indexing to release the sealing pressure and allow filter belt indexing movement.

Abstract: A lift station for raising the level of an open channel flow of liquid by sweeping blades mounted to a rotated wheel into the liquid flow after entering a housing to sweep the liquid up and back along a housing interior wall and over a weir edge located well above the level of the open channel flow stream. The flow stream is caused to descend as it enters the housing through a drop to increase the flow velocity to a degree sufficient to offset the impeding effect on upstream flow of the encounter of the flow with the rotating blades. Roller bearings are mounted to the inside of the housing to side walls to support the bladed wheel and are packed with a solid lubricant to insure a long service life despite being exposed to the liquid and debris entrained therein. A reverse rotation device positively prevents a backwards rotation of the wheel to prevent damage to the blades. The wheel is driven by a motor mounted in a housing tray affixed to one side wall driving a drive shaft penetrating the side wall.

Abstract: An arrangement and method for maintaining a minimum flow velocity in return piping receiving dirty coolant from a plurality of machine tools receiving filtered coolant from a filter apparatus. A bypass line diverts clean coolant into the return piping via a pressure reducing valve set to allow make up flow of clean coolant into the return piping just sufficient to maintain a pressure corresponding to the minimum flow velocity in the return piping. A pressure maintaining valve is interposed upstream of the pressure reducing valve and set to restrict flow as necessary to maintain adequate pressure to insure that the machine tools are adequately supplied with clean coolant at start up prior to the beginning of contaminated flow in the return piping.

Abstract: An arrangement and method for maintaining a minimum flow velocity in return piping receiving dirty coolant from a plurality of machine tools receiving filtered coolant from a filter apparatus. A bypass line diverts clean coolant into the return piping via a pressure reducing valve set to allow make up flow of clean coolant into the return piping just sufficient to maintain a pressure corresponding to the minimum flow velocity in the return piping. A pressure maintaining valve is interposed upstream of the pressure reducing valve and set to restrict flow as necessary to maintain adequate pressure to insure that the machine tools are adequately supplied with clean coolant at start up prior to the beginning of contaminated flow in the return piping.

Abstract: A filtering apparatus and method is disclosed adapted to filter suspended solids from a liquid, consisting of a filter housing which receives a flexible belt filtering element into a filter chamber, the liquid to be passed through the belt to filter out solids. The flexible belt is movably mounted to be passed through end openings on either side of a filter chamber to enable removal of accumulated solids after each filter cycle. The end openings are sealed during filtering cycles by flexible tube segments extending across the openings which are pressurized to effect a seal and evacuated to allow removal of the belt. A series of such filters may be stacked together with a traveling roller assembly utilized for simultaneously moving the belts of each filter in and out of the chamber.