Automatic self-cleaning grill for rough screening water, effluent etc. - has motorised rake which is cleared after each operating stroke

摘要

Screening grill installation for trapping rubbish suspended in water to be treated has vertical, spaced bars with gaps which can be combed clear by the teeth of a vertically displacable rake. The rake is fixed to one end of a support tube which is powered to move the rake as well as to disengage its teeth from the grill. During the disengagement, which takes place at the top of the strok of the rake, the teeth are drawn across a scraper which clears rubbish from the rake. The support tube is pref. connected by cable to a lifting winch. The tube pref. rises between guide rollers fitted in a pivoted bracket which can be moved by a fluid power cylinder to disengage the rake. The scraper which clears the rake is pref. a rubber blade fixed on resilient mountings. Used for rough filtration of water at pump stations, river water extn. plants, waste water treatment plants etc. Appts. can be constructed as a packaged, monobloc unit. The unit is compact, simple and comparatively inexpensive; it is easily fitted into existing installations. The rake action can be automatically programmed on an electric timer.