Laundry Treatment Machine And A Sensor For Sensing the Quality of Water Therefor

Abstract

A wash water sensing apparatus of a laundry treatment machine is provided. The wash water sensing apparatus includes a sealing cover coupled to the tub by being inserted into a hole of the tub, the sealing cover including a through hole; and a sensor body including a plurality of electrodes for measuring the conductivity of wash water and coupled to the sealing cover by being inserted into the through hole. Therefore, it is possible to simplify the structure of a laundry treatment machine and facilitate the assembly of a laundry treatment machine.

1 . A wash water sensing apparatus of a laundry treatment machine, the wash water sensing apparatus comprising:
 a sealing cover coupled to a tub by being inserted into a hole of the tub, the sealing cover including a through hole; and   a sensor body including a plurality of electrodes for measuring the conductivity of wash water and coupled to the sealing cover by being inserted into the through hole.   
     
     
         2 . The wash water sensing apparatus of  claim 1 , wherein the sealing cover is more elastic than the sensor body. 
     
     
         3 . The wash water sensing apparatus of  claim 1 , wherein the sealing cover further includes a cover insertion portion formed so as to be able to be inserted into the hole of the tub and the outer diameter of the cover insertion portion is greater than the diameter of the hole of the tub when the sealing cover is yet to be inserted into the hole of the tub. 
     
     
         4 . The wash water sensing apparatus of  claim 1 , wherein the sensor body further includes a body insertion portion formed as a protrusion so as to be able to be inserted into the through hole and the outer diameter of the body insertion portion is greater than the diameter of the through hole when the sensor body is yet to be inserted into the through hole. 
     
     
         5 . The wash water sensing apparatus of  claim 1 , wherein the sensor body is formed through injection molding and the electrodes are inserted into the sensor body during the formation of the sensor body. 
     
     
         6 . The wash water sensing apparatus of  claim 1 , wherein at least one surface of each of the electrodes is disposed on a level with a surface of the sensor body. 
     
     
         7 . The wash water sensing apparatus of  claim 6 , wherein the electrodes are inserted into the sensor body so that at least one surface of each of the electrodes can be exposed on the surface of the sensor body. 
     
     
         8 . The wash water sensing apparatus of  claim 6 , wherein the electrodes are formed as plates so as to be able to be attached onto the sensor body. 
     
     
         9 . The wash water sensing apparatus of  claim 6 , wherein the sensor body further includes first and second protrusions facing each other and the electrodes include first and second electrodes disposed on the first and second protrusions, respectively. 
     
     
         10 . The wash water sensing apparatus of  claim 1 , wherein the sensor body includes at least three electrodes, at least one of the three electrodes has a different length from the other electrodes, and at least two of the three electrodes are selectively used to measure the conductivity of wash water in consideration of the concentration of detergent. 
     
     
         11 . The wash water sensing apparatus of  claim 10 , wherein two of the three electrodes producing a largest voltage variation for a detergent concentration variation are used to measure the conductivity of wash water. 
     
     
         12 . The wash water sensing apparatus of  claim 10 , wherein a detergent concentration section is divided into a first concentration section and a second concentration section corresponding to a higher detergent concentration than the first concentration section according to the concentration of detergent, the first and second longest electrodes of the three electrodes are used during the first concentration section, and the longest electrode and the shortest electrode of the three electrodes are used during the second concentration section. 
     
     
         13 . The wash water sensing apparatus of  claim 10 , wherein, during a washing operation, the conductivity of wash water is measured by applying a current to the longest electrode of the three electrodes and the shortest electrode of the three electrodes. 
     
     
         14 . The wash water sensing apparatus of  claim 10 , wherein, during a rinsing operation, the conductivity of wash water is measured by applying a current to the first and second longest electrodes of the three electrodes. 
     
     
         15 . The wash water sensing apparatus of  claim 1 , wherein the sensor body further includes an optical sensor measuring the pollution level of wash water. 
     
     
         16 . The wash water sensing apparatus of  claim 15 , wherein the sensor body also includes first and second protrusions facing each other and the optical sensor includes a light emitter disposed on the first protrusion and emitting light and a light receptor disposed on the second protrusion and receiving the light emitted by the light emitter. 
     
     
         17 . A laundry treatment machine comprising:
 a tub in which wash water is loaded;   a sealing cover coupled to the tub by being inserted into a hole of the tub, the sealing cover including a through hole; and   a sensor body including a plurality of electrodes for measuring the conductivity of wash water and coupled to the sealing cover by being inserted into the through hole.   
     
     
         18 . The laundry treatment machine of  claim 17 , wherein at least one surface of each of the electrodes is disposed on a level with a surface of the sensor body. 
     
     
         19 . The laundry treatment machine of  claim 17 , wherein the sensor body includes at least three electrodes, at least one of the three electrodes has a different length from the other electrodes, and at least two of the three electrodes are selectively used to measure the conductivity of wash water in consideration of the concentration of detergent. 
     
     
         20 . The laundry treatment machine of  claim 17 , wherein the sensor body further includes an optical sensor measuring the pollution level of wash water.