Liquid treatment unit, toilet seat with washer, washing machine, and liquid treatment apparatus

Abstract

A liquid treatment unit includes: a treatment tank provided with an inlet and an outlet, the treatment tank having a shape that allows a portion of liquid to be retained; a controller that controls supply of liquid into the treatment tank and ejection of liquid from the treatment tank; and a plasma generator generates plasma in the liquid inside the treatment tank. The plasma generator generates plasma while the controller stops supply of liquid and ejection of liquid. After the liquid has been treated, the controller resumes the supply of liquid, and causes the liquid to be ejected from the treatment tank while allowing a portion of the treated liquid to be retained inside the treatment tank.

What is claimed is: 
     
         1 . A liquid treatment unit comprising:
 a treatment tank provided with an inlet and an outlet, the treatment tank having a shape that allows a portion of liquid to be retained;   a controller that controls supply of liquid into the treatment tank and ejection of liquid from the treatment tank; and   a plasma generator that generates plasma in the liquid inside the treatment tank,   wherein the plasma generator generates plasma to cause the liquid to be treated while the controller stops supply of liquid and ejection of liquid in a state where the liquid is present inside the treatment tank, and   after the liquid has been treated, the controller resumes the supply of liquid into the treatment tank, and causes the liquid to be ejected from the treatment tank while allowing a portion of the treated liquid to be retained inside the treatment tank.   
     
     
         2 . The liquid treatment unit according to  claim 1 ,
 wherein, prior to stopping the supply of liquid and the ejection of liquid, the controller causes the liquid to be supplied into the treatment tank.   
     
     
         3 . The liquid treatment unit according to  claim 1 ,
 wherein, when the liquid is ejected while allowing a portion of the treated liquid to be retained inside the treatment tank, the plasma generator further generates the plasma in the liquid inside the treatment tank.   
     
     
         4 . The liquid treatment unit according to  claim 1 ,
 wherein, when the liquid is ejected while allowing a portion of the treated liquid to be retained inside the treatment tank, the quantity of the liquid ejected from the treatment tank is equal to or greater than the volume of the treatment tank.   
     
     
         5 . The liquid treatment unit according to  claim 1 ,
 wherein a cross section of the outlet is smaller than a cross section of an internal space of the treatment tank.   
     
     
         6 . The liquid treatment unit according to  claim 5 ,
 wherein the plasma generator generates a gas bubble, a cross section of the gas bubble being smaller than the cross section of the internal space of the treatment tank.   
     
     
         7 . The liquid treatment unit according to  claim 1 , further comprising:
 a circulation flow passage extending from the outlet to the inlet; and   a distributor that causes a portion of the liquid ejected from the treatment tank to be recirculated to the treatment tank through the circulation flow passage.   
     
     
         8 . The liquid treatment unit according to  claim 1 , further comprising:
 a gas-liquid separator provided in a flow passage upstream or downstream from the treatment tank, the gas-liquid separator extracting gas from a mixture of the liquid and gas and emitting the gas to outside.   
     
     
         9 . The liquid treatment unit according to  claim 1 ,
 wherein the plasma generator comprises:   a first electrode at least a portion of which is arranged inside the treatment tank;   a second electrode at least a portion of which is arranged inside the treatment tank;   an insulator surrounding the periphery of the first electrode with a space therebetween, the insulator having an opening through which the space communicates the inside of the treatment tank;   a power source that applies a voltage between the first electrode and the second electrode; and   a gas supply device that supplies gas to the space.   
     
     
         10 . The liquid treatment unit according to  claim 9 ,
 wherein at least part of the first electrode includes a region where a conductor surface thereof is exposed, and   wherein, when the region is covered by the gas, the power source applies the voltage.   
     
     
         11 . The liquid treatment unit according to  claim 1 ,
 wherein the plasma generator comprises:   a first electrode at least a portion of which is arranged inside the treatment tank;   a second electrode at least a portion of which is arranged inside the treatment tank;   an insulator surrounding the periphery of the first electrode with a space therebetween, the insulator having an opening through which the space communicates the inside of the treatment tank; and   a power source that applies a voltage between the first electrode and the second electrode.   
     
     
         12 . The liquid treatment unit according to  claim 11 ,
 wherein at least part of the first electrode includes a region where a conductor surface thereof is exposed, and   wherein the power source applies the voltage, vaporizing liquid inside the space to produce gas, and causing discharge when the region is covered by the gas.   
     
     
         13 . A toilet seat with a washer comprising:
 the liquid treatment unit according to  claim 1 ; and   a washing nozzle to which the liquid ejected from the treatment tank is supplied.   
     
     
         14 . The toilet seat with a washer according to  claim 13 , further comprising:
 an input part that receives an instruction of washing from a user,   wherein the controller stops the supply of liquid and the ejection of liquid prior to receiving the instruction from the input part,   the plasma generator generates the plasma in the liquid inside the treatment tank while the supply of liquid and the ejection of liquid are stopped, and   the controller, based on the instruction from the input part, causes the liquid to be ejected to the washing nozzle while allowing a portion of the treated liquid to be retained inside the treatment tank.   
     
     
         15 . A washing machine comprising:
 the liquid treatment unit according to  claim 1 ; and   a washing tub to which the liquid ejected from the treatment tank is supplied.   
     
     
         16 . The washing machine according to  claim 15 , further comprising:
 an input part that receives an instruction of starting washing from a user,   wherein the controller stops the supply of liquid and the ejection of liquid on the basis of the instruction from the input part,   the plasma generator generates the plasma in the liquid inside the treatment tank while the supply of liquid and the ejection of liquid are stopped, and   the controller, after the liquid has been treated, causes the liquid to be ejected to the washing tub while allowing a portion of the treated liquid to be retained inside the treatment tank.   
     
     
         17 . A liquid treatment apparatus comprising:
 the liquid treatment unit according to  claim 1 ; and   a water inlet to which the liquid ejected from the treatment tank is supplied,   the liquid treatment apparatus being the one selected from the group consisting of a water purifying apparatus, an air conditioner, a humidifier, an electric shaver washer, a dish washer, a processing apparatus for hydroponic culture, and an apparatus for circulating nourishing solution.   
     
     
         18 . A liquid treatment unit comprising:
 a treatment tank provided with an inlet and an outlet, the treatment tank having a shape that allows a portion of liquid to be retained;   a plasma generator that generates plasma in the liquid in a state where the liquid is present inside the treatment tank;   a circulation flow passage extending from the outlet to the inlet; and   a distributor that causes a portion of the liquid ejected from the treatment tank to be recirculated to the treatment tank through the circulation flow passage.