Lift station and method
View Patent ↗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. The housing tray collects any liquid leaking past the shaft and has a sloping bottom directing liquid back towards a drain hole in the housing side wall.
1. A method of raising the level of liquid in an open channel flow of liquid flowing down an inclined bottom collection trough extending beneath a machine tool installation to collect draining cutting fluid and entrained chips to form an open channel liquid flow stream within said collection trough, comprising the steps of:
guiding said open channel liquid stream in said collection trough into a housing having a bottom surface configured to receive said flowing liquid stream;
successively sweeping each of a plurality of blades into said flowing liquid stream to sweep liquid and chips along said housing bottom surface and up an upwardly curving wall surface into an exit chute extending back in a reverse direction from said flowing liquid stream, and over a weir edge located in said exit chute;
causing said open channel flow stream to plunge down into the region whereat blades sweep into said flow stream through a vertical drop sufficient to prevent a substantial disturbance in said open channel flow upstream from said region whereat said blades sweep into said flow.
2. The method according to claim 1 wherein said vertical drop comprises a distance approximately three inches to cause a sufficient increase in flow to prevent said upstream disturbance.