FLUSH VALVE FOR STOOL AND AUTOMATIC PRELIMINARY WASHING METHOD FOR SIPHON TYPE WESTERN STOOL

摘要

PURPOSE: To prevent shortage of trap water after preliminary washing of a siphon type stool. ;CONSTITUTION: A bypass passage 38 is provided which communicates the main passages 22, 24 of a flush valve 20 with each other and a switching valve 40 is provided within the bypass passage 38. When a sensor 16 detects a human body, a control valve 36 is opened for a predetermined short time and a piston main valve 28 is separated from a valve seat portion 32 for a predetermined short time and preliminary wash water is supplied to a stool by the main passages 22, 24. After preliminary washing is completed, the switching valve 40 is opened to feed trap supply water to the stool through the main passage 22, the bypass passage 38 and the main passage 24. Therefore, a siphon is formed during the preliminary washing and the level of the trap water is heightened to a normal level by the trap supply water even if the level of the trap water is lowered. The siphon for main washing can thus surely be strengthened. Also, dirt is prevented from attaching to the inner surface of the bowl of the stool.;COPYRIGHT: (C)1993,JPO&Japio