Dish washer and control method thereof

Abstract

A dish washer includes a washing tub accommodating a detergent containing a first enzyme activated at an active temperature range and a second enzyme activated at another active temperature range differing from the active temperature range of the first enzyme, and wash water in which the detergent is dissolved, a heating unit heating wash water, and a controller controls driving of the heating unit such that the temperature of wash water is maintained within the active temperature range of the first enzyme for a first designated time, and controls driving of the heating unit such that the temperature of wash water is maintained within the active temperature range of the second enzyme for a second designated time, when the first designated time has elapsed.

What is claimed is: 
     
         1 . A dish washer comprising:
 a washing tub accommodating a detergent containing a first enzyme activated at an active temperature range and a second enzyme activated at another active temperature range differing from the active temperature range of the first enzyme, and wash water in which the detergent is dissolved;   a heating unit heating wash water; and   a controller to control driving of the heating unit such that the temperature of wash water is maintained within the active temperature range of the first enzyme for a first designated time, and controls driving of the heating unit such that the temperature of wash water is maintained within the active temperature range of the second enzyme for a second designated time, when the first designated time has elapsed.   
     
     
         2 . The dish washer according to  claim 1 , wherein the first enzyme is α-amylase, and the second enzyme is protease. 
     
     
         3 . The dish washer according to  claim 1 , further comprising a temperature detection unit detecting the temperature of wash water,
 wherein the controller controls driving of the heating unit based on the detected temperature of the wash water.   
     
     
         4 . The dish washer according to  claim 1 , wherein:
 the active temperature range of the first enzyme is 32° C. to 38° C.; and   the active temperature range of the second enzyme is 45° C. to 55° C.   
     
     
         5 . The dish washer according to  claim 4 , wherein the controller controls driving of the heating unit such that the temperature of wash water is raised step by step within the active temperature range of the first enzyme. 
     
     
         6 . The dish washer according to  claim 5 , wherein:
 the active temperature range of the first enzyme includes a first maintenance temperature range and a second maintenance temperature range higher than the first maintenance temperature range; and   the controller controls driving of the heating unit such that the temperature of wash water is maintained within the first maintenance temperature range for a first maintenance time, and controls driving of the heating unit such that the temperature of wash water is maintained within the second maintenance temperature range for a second maintenance time.   
     
     
         7 . The dish washer according to  claim 1 , further comprising:
 a sump provided within the washing tub;   a circulation unit circulating wash water in the sump; and   a nozzle unit jetting wash water supplied from the circulation unit,   wherein the controller controls driving of the circulation unit for the first designated time such that wash water maintained within the active temperature range of the first enzyme is circulated and jetted, and controls driving of the circulation unit for the second designated time such that wash water maintained within the active temperature range of the second enzyme is circulated and jetted.   
     
     
         8 . The dish washer according to  claim 1 , further comprising:
 a first basket;   a second basket provided above the first basket; and   a cutlery basket provided above the second basket,   wherein the nozzle unit includes a first nozzle provided below the first basket, a second nozzle provided between the first basket and the second basket, and a third nozzle provided above the cutlery basket.   
     
     
         9 . The dish washer according to  claim 8 , further comprising:
 a first valve blocking wash water supplied to the first nozzle;   a second valve blocking wash water supplied to the second nozzle; and   a third valve blocking wash water supplied to the third nozzle,   wherein the controller controls opening and closing of the first, second and third valves such that the amount of wash water jetted through the first nozzle is greater than the amount of wash water jetted through the second and third nozzles during control for the first designated time.   
     
     
         10 . The dish washer according to  claim 9 , wherein the controller controls opening and closing of the second and third valves such that the amount of wash water jetted through the second nozzle is greater than the amount of wash water jetted through the third nozzle. 
     
     
         11 . The dish washer according to  claim 10 , wherein the controller controls at least one of opening degrees, opening times and the numbers of opening frequencies of the first, second and third valves. 
     
     
         12 . The dish washer according to  claim 8 , wherein the controller controls opening and closing of the first, second and third valves such that the amount of wash water jetted through the second nozzle is greater than the amount of wash water jetted through the first and third nozzles during control for the second designated time. 
     
     
         13 . The dish washer according to  claim 12 , wherein the controller controls opening and closing of the first and third valves such that the amount of wash water jetted through the third nozzle is greater than the amount of wash water jetted through the first nozzle. 
     
     
         14 . A dish washer comprising:
 a heating unit heating wash water in which a detergent containing a first enzyme activated at an active temperature range and a second enzyme activated at another active temperature range differing from the active temperature range of the first enzyme is dissolved;   a circulation unit circulating wash water;   a nozzle unit jetting wash water; and   a controller to control driving of the heating unit to heat wash water, stops driving of the heating unit and controls driving of the circulation unit and the nozzle unit for a first designated time to circulate and jet wash water if the temperature of heated wash water is within the active temperature range of the first enzyme, controls driving of the heating unit to reheat wash water when the first designated time has elapsed, and stops driving of the heating unit and controls driving of the circulation unit and the nozzle unit for a second designated time to circulate and jet wash water if the temperature of reheated wash water is within the active temperature range of the second enzyme.   
     
     
         15 . The dish washer according to  claim 14 , wherein the first enzyme is α-amylase, and the second enzyme is protease. 
     
     
         16 . The dish washer according to  claim 14 , wherein the controller controls driving of the heating unit such that the temperature of wash water is raised step by step within the active temperature range of the first enzyme. 
     
     
         17 . The dish washer according to  claim 16 , wherein:
 the active temperature range of the first enzyme includes a first maintenance temperature range and a second maintenance temperature range higher than the first maintenance temperature range; and   the controller controls driving of the heating unit such that the temperature of wash water is maintained within the first maintenance temperature range for a first maintenance time, and controls driving of the heating unit such that the temperature of wash water is maintained within the second maintenance temperature range for a second maintenance time.   
     
     
         18 . The dish washer according to  claim 17 , wherein the first maintenance time is longer than the second maintenance time. 
     
     
         19 . The dish washer according to  claim 14 , further comprising:
 a first basket;   a second basket provided above the first basket; and   a cutlery basket provided above the second basket,   wherein the nozzle unit includes a first nozzle provided below the first basket, a second nozzle provided between the first basket and the second basket, and a third nozzle provided above the cutlery basket.   
     
     
         20 . The dish washer according to  claim 19 , further comprising:
 a first valve blocking wash water supplied to the first nozzle;   a second valve blocking wash water supplied to the second nozzle; and   a third valve blocking wash water supplied to the third nozzle,   wherein the controller controls opening and closing of the first, second and third valves such that the amount of wash water jetted through the first nozzle is greater than the amount of wash water jetted through the second and third nozzles during control for the first designated time.   
     
     
         21 . The dish washer according to  claim 20 , further comprising a temperature detection unit detecting the temperature of wash water,
 wherein the controller controls opening of the first, second and third valves such that wash water is jetted through the first, second and third nozzles if the detected temperature of wash water is not within the active temperature range of the first enzyme.   
     
     
         22 . The dish washer according to  claim 20 , further comprising a temperature detection unit detecting the temperature of wash water,
 wherein the controller controls opening of the second valve such that wash water is jetted through the second nozzle if the detected temperature of wash water is not within the active temperature range of the first enzyme.   
     
     
         23 . The dish washer according to  claim 20 , further comprising a temperature detection unit detecting the temperature of wash water,
 wherein the controller controls opening and closing of the first, second and third valves such that a first jet pattern of jetting wash water through the first, second and third nozzles and a second jet pattern of jetting wash water through the first nozzle are alternately executed if the detected temperature of wash water is within the active temperature range of the first enzyme.   
     
     
         24 . The dish washer according to  claim 23 , wherein the controller simultaneously opens the first, second and third valves during control using the first jet pattern. 
     
     
         25 . The dish washer according to  claim 23 , wherein the controller alternately opens the first, second and third valves in predetermined sequence during control using the first jet pattern. 
     
     
         26 . The dish washer according to  claim 14 , wherein the controller controls driving of the heating unit such that the temperature of wash water is raised by a designated temperature when the first designated time has elapsed. 
     
     
         27 . The dish washer according to  claim 26 , wherein the controller controls driving of the heating unit such that the raised temperature of wash water is maintained for a predetermined time. 
     
     
         28 . A control method of a dish washer which has a washing tub and a heating unit heating wash water in the washing tub, comprising:
 heating, circulating and jetting wash water in which a detergent is dissolved, when water is supplied to the washing tub;   detecting the temperature of wash water in the washing tub;   judging whether or not the detected temperature of wash water is within an active temperature range of a first enzyme contained in the detergent;   circulating and jetting wash water within the active temperature range of the first enzyme for a first designated time while maintaining the temperature of wash water within the active temperature range of the first enzyme, upon judging that the detected temperature of wash water is within the active temperature range of the first enzyme;   reheating wash water when the first designated time has elapsed;   detecting the temperature of reheated wash water in the washing tub;   judging whether or not the detected temperature of reheated wash water is within an active temperature range of a second enzyme contained in the detergent;   circulating and jetting wash water within the active temperature range of the second enzyme for a second designated time while maintaining the temperature of wash water within the active temperature range of the second enzyme, upon judging that the detected temperature of wash water is within the active temperature range of the second enzyme; and   turning the heating unit off when the second designated time has elapsed.   
     
     
         29 . The control method according to  claim 28 , wherein the circulating and jetting of wash water within the active temperature range of the first enzyme for the first designated time while maintaining the temperature of wash water within the active temperature range of the first enzyme includes raising the temperature of wash water step by step within the active temperature range of the first enzyme. 
     
     
         30 . The control method according to  claim 29 , wherein the raising of the temperature of wash water step by step within the active temperature range of the first enzyme includes:
 maintaining the temperature of wash water within a first maintenance temperature range for a first maintenance time; and   maintaining the temperature of wash water within a second maintenance temperature range for a second maintenance time by reheating wash water, when the first maintenance time has elapsed.   
     
     
         31 . The control method according to  claim 28 , wherein the circulating and jetting of wash water includes:
 pumping wash water in the washing tub; and   respectively controlling opening and closing of a first valve blocking wash water supplied to a first nozzle provided below a first basket, a second valve blocking wash water supplied to a second nozzle provided between the first basket and a second basket, and a third valve blocking wash water supplied to a third nozzle provided above a cutlery basket.   
     
     
         32 . The control method according to  claim 31 , wherein the circulating and jetting of wash water within the active temperature range of the first enzyme includes controlling opening and closing of the first, second and third valves such that the amount of wash water jetted through the first and second nozzles is greater than the amount of wash water jetted through the third nozzle. 
     
     
         33 . The control method according to  claim 32 , wherein the circulating and jetting of wash water within the active temperature range of the first enzyme further includes controlling opening and closing of the first and second valves such that the amount of wash water jetted through the first nozzle is greater than the amount of wash water jetted through the second nozzle. 
     
     
         34 . The control method according to  claim 31 , wherein the controlling of opening and closing of the first, second and third valves includes controlling at least one of opening degrees, opening times and the numbers of opening frequencies of the first, second and third valves. 
     
     
         35 . The control method according to  claim 31 , wherein the circulating and jetting of wash water within the active temperature range of the second enzyme includes controlling opening and closing of the first, second and third valves such that the amount of wash water jetted through the second and third nozzles is greater than the amount of wash water jetted through the first nozzle. 
     
     
         36 . The control method according to  claim 35 , wherein the circulating and jetting of wash water within the active temperature range of the second enzyme further includes controlling opening and closing of the second and third valves such that the amount of wash water jetted through the second nozzle is greater than the amount of wash water jetted through the third nozzle. 
     
     
         37 . The control method according to  claim 31 , further comprising controlling opening of the first, second and third valves such that wash water is simultaneously jetted through the first, second and third nozzles, upon judging that the detected temperature of wash water is not within the active temperature range of the first enzyme. 
     
     
         38 . The control method according to  claim 31 , further comprising controlling opening of the first, second and third valves such that wash water is alternately jetted through the first, second and third nozzles, upon judging that the detected temperature of wash water is not within the active temperature range of the first enzyme. 
     
     
         39 . The control method according to  claim 31 , further comprising controlling opening of the second valve such that wash water is jetted through the second nozzle, upon judging that the detected temperature of wash water is not within the active temperature range of the first enzyme. 
     
     
         40 . The control method according to  claim 31 , wherein the circulating and jetting of wash water within the active temperature range of the first enzyme includes controlling opening and closing of the first, second and third valves such that a first jet pattern of jetting wash water through the first, second and third nozzles and a second jet pattern of jetting wash water through the first nozzle are alternately executed. 
     
     
         41 . The control method according to  claim 40 , wherein the controlling of opening and closing of the first, second and third valves using the first jet pattern includes simultaneously opening the first, second and third valves. 
     
     
         42 . The control method according to  claim 40 , wherein the controlling of opening and closing of the first, second and third valves using the first jet pattern includes alternately opening the first, second and third valves in predetermined sequence.