Toilet flushing device and flush toilet

Abstract

Providing a toilet flushing device and a flush toilet both of which can desirably execute toilet flushing. A toilet flushing device ( 20 ) includes a first tank ( 21 ) storing flush water, a second tank ( 22 ) having a lower opening ( 22 C) communicating with the first tank ( 21 ) and having a lower region ( 22 D) and an upper region ( 22 U) with a larger capacity per unit height than the lower region ( 22 D), an air passage ( 23 ) communicating between the second tank ( 22 ) and a toilet drainage ( 12 ) via a position located higher than a maximum storage water level (L) in the first tank ( 21 ), a water-supply passage ( 24 ) communicating between the first tank ( 21 ) and a toilet bowl ( 11 ) and a on-off valve ( 25 ) which maximizes a flow rate of an air in the air passage ( 23 ) with a delay to initiation of supply of flush water stored in the first tank ( 21 ) through the water-supply passage ( 24 ) into the toilet bowl ( 11 ), the air flowing from the toilet drainage ( 12 ) side to the second tank ( 22 ) side.

1 . A toilet flushing device which supplies flush water to a toilet body including a toilet bowl and a toilet drainage communicating with a downstream side of the toilet bowl, the toilet flushing device comprising:
 a first tank which stores flush water;   a second tank having a lower opening communicating with the first tank and an interior including a lower region and an upper region having a larger capacity per unit height than the lower region;   an air passage communicating between the second tank and the toilet drainage via a position located higher than a maximum storage water level in the first tank;   a water-supply passage communicating between the first tank and the toilet bowl; and   a delay unit which maximizes a flow rate of an air in the air passage with a delay to initiation of supply of flush water stored in the first tank through the water-supply passage into the toilet bowl, the air flowing from the toilet drainage side to the second tank side.   
     
     
         2 . The toilet flushing device according to  claim 1 , wherein the first tank has an interior including a lower region and an upper region having a smaller capacity per unit height than the lower region. 
     
     
         3 . A toilet flushing device which supplies flush water to a toilet body including a toilet bowl and a toilet drainage communicating with a downstream side of the toilet bowl, the toilet flushing device comprising:
 a first tank configured to store flush water and having an interior including a lower region and an upper region having a smaller capacity per unit height than the lower region;   a second tank having a lower opening communicating with the first tank;   an air passage communicating between the second tank and the toilet drainage via a position located higher than a maximum storage water level in the first tank;   a water-supply passage communicating between the first tank and the toilet bowl; and   a delay unit which maximizes a flow rate of an air in the air passage with a delay to initiation of supply of flush water stored in the first tank through the water-supply passage into the toilet bowl, the air flowing from the toilet drainage side to the second tank side.   
     
     
         4 . The toilet flushing device according to any one of  claims 1  to  3 , wherein the lower opening of the second tank communicates with the first tank at a location lower than a minimum storage water level of the first tank. 
     
     
         5 . The toilet flushing device according to any one of  claims 1  to  3 , wherein the delay unit is an on-off valve which is provided in the air passage so as to open and close the air passage. 
     
     
         6 . The toilet flushing device according to any one of claims  1  to  3 , wherein the second tank is accommodated in the first tank. 
     
     
         7 . A toilet flushing device which supplies flush water to a toilet body including a toilet bowl and a toilet drainage communicating with a downstream side of the toilet bowl, the toilet flushing device comprising:
 a first tank into which flush water flows and which stores the flush water;   a second tank communicating with a lower part of the first tank;   an air passage communicating between the second tank and the toilet drainage;   a water-supply passage communicating between the first tank and the toilet bowl; and   a flush water control unit configured to control a flow rate of the flush water supplied from the first tank to the toilet bowl.   
     
     
         8 . The toilet flushing device according to  claim 7 , wherein the flush water control unit includes a pump provided in the water-supply passage. 
     
     
         9 . The toilet flushing device according to  claim 7  or  8 , further comprising a suction control unit configured to control an air sucking operation of the second tank sucking an air from the toilet drainage. 
     
     
         10 . The toilet flushing device according to,  claim 9 , wherein the suction control unit includes an upper water storage chamber and a lower water storage chamber formed by dividing the second tank by a partition wall having an orifice. 
     
     
         11 . The toilet flushing device according to  claim 10 , further comprising a closing member which is configured to float in the flush water in the lower water storage chamber thereby to close the orifice. 
     
     
         12 . A flush toilet comprising a toilet body having a toilet bowl and a toilet drainage communicating with a downstream side of the toilet bowl, and the toilet flushing device defined in  claim 1  or  7 . 
     
     
         13 . A toilet flushing device which supplies flush water to a toilet body, the device comprising:
 a first tank into which flush water flows and which stores the flush water;   a third tank having an inlet through which flush water flows from a lower part of the fire t tank thereinto and an outlet provided above the inlet and communicating with the toilet body, the third tank being maintained in a state full of flush water under an influence of pressure of flush water in the first tank when air is prevented from flowing through the inlet from the first tank in a case where flush water is supplied to the toilet body;   a let pump disposed at a position where the jet pump is opposed to the outlet in the third tank with a space therebetween, the jet pump having a nozzle ejecting flush water toward the outlet; and   a water-supply passage communicating between the outlet and the toilet body.   
     
     
         14 . The toilet flushing device according to  claim 13 , wherein the outlet is formed so as to extend through an upper part of the third tank, and the nozzle is provided in an upper interior of the third tank. 
     
     
         15 . The toilet flushing device according to  claim 13  or  14 , wherein the nozzle ejects flush water until air flows from the first tank through the inlet into the third tank with a result that the water level in the third tank drops. 
     
     
         16 . The toilet flushing device according to  claim 15 , wherein the water level in the first tank, at which air starts to flow from the first tank through the inlet into the third tank is changeable. 
     
     
         17 . The toilet flushing device according to  claim 13  or  14 , further comprising a communication passage which communicates between a lower part of the first tank and the nozzle and a water feed unit which is provided in the communication passage for feeding flush water stored in the first tank to the nozzle. 
     
     
         18 . A flush toilet comprising a toilet body and the toilet flushing device defined in  claim 13  or  14 .