Patent ID: 9050563
Filing Date: 2015-06-09
Classification: B01D,C02F,Y02A

Abstract:
1. A filtering device comprising: a primary filtration unit for filtering a raw water, which unit includes a filtrate passage for discharging filtrate water from the filter; a conveyance valve disposed on the filtrate passage for conveyance of filtrate water; a drain passage in fluid connection with the drain port; a drain valve disposed on the drain passage for passage of the fluid used for backwashing and the raw water; a communication passage for communicating the filtrate passage with the drain passage, the communication passage branching off from the filtrate passage upstream of the conveyance valve and is in fluid connection with the drain passage; a switching valve for selectively opening or closing the communication passage; and a controller that controls the conveyance valve, the switching valve, and the drain valve, and controls the operation of the port in the housing that alternately serves as a raw water supplying port and as the drain port.