Washing machine and control method thereof

Abstract

A washing machine and a control method thereof in which laundry is washed in a state of being directly heated by steam. The washing machine includes a microcomputer for controlling the overall operation of the washing machine to wash laundry by using steam. The microcomputer controls operations of wetting laundry with a small amount of water prior to generation of steam, uniformly spraying detergent over the wet laundry, and injecting steam onto the laundry. Accordingly, it is possible to achieve a reduction in the amount of water to be used and a reduction in wash time while preventing the laundry from being stained or damaged during the wash operation using steam.

1 . A washing machine comprising: 
 a rotating drum for containing laundry;    a drum driving unit for driving the rotating drum;    a steam generator for generating steamand supplying the steam into the rotating drum; and    a controller for controlling operations of injecting the steam supplied from the steam generator into the rotating drum to heat the laundry into heated laundry, and washing the heated laundry.    
   
   
       2 . The washing machine according to  claim 1 , further comprising: 
 a water supply unit for supplying water into the rotating drum,    wherein the controller drives the water supply unit to wet the laundry with water into wet laundry before the operation of washing the heated laundry.    
   
   
       3 . The washing machine according to  claim 2 , wherein the controller controls the drum driving unit to rotate the rotating drum in forward and reverse directions in an alternating fashion while the laundry is wetted by the water.  
   
   
       4 . The washing machine according to  claim 2 , further comprising: 
 a detergent dissolving unit for supplying a detergent solution into the rotating drum,    wherein the controller drives the detergent dissolving unit to spray the detergent solution over the wet laundry.    
   
   
       5 . The washing machine according to  claim 4 , wherein the controller controls the drum driving unit to rotate the rotating drum at a predetermined speed before the detergent solution is sprayed.  
   
   
       6 . The washing machine according to  claim 5 , wherein the predetermined speed is a speed sufficient to bring the laundry into constant contact with an inner peripheral surface of the rotating drum while defining an empty space at a central interior of the rotating drum.  
   
   
       7 . The washing machine according to  claim 5 , wherein the controller controls the detergent dissolving unit to spray the detergent solution when a rotating speed of the drum corresponds to the predetermined speed, and controls the drum driving unit to reduce the rotating speed of the rotating drum while the detergent solution is being sprayed.  
   
   
       8 . The washing machine according to  claim 4 , wherein the controller controls the drum driving unit to rotate the rotating drum in forward and reverse directions in an alternating fashion to transfer the detergent solution sprayed over the laundry over substantially all portions of the laundry.  
   
   
       9 . The washing machine according to  claim 1 , wherein the steam generator comprises a heating tank for containing water, and a heater installed in the heating tank adapted to heat the water in the heating tank, thereby generating steam, the heater being controlled by the controller.  
   
   
       10 . The washing machine according to  claim 9 , wherein the steam generator further comprises a water level sensor for sensing a water level in the steam generator, and a water temperature sensor for sensing a water temperature in the steam generator, the water level sensor and water temperature sensor providing, to the controller, information about the water level and water temperature sensed thereby.  
   
   
       11 . The washing machine according to  claim 9 , wherein the steam generator further comprises a steam supply valve installed at an outlet of the heating tank, and the controller opens the steam supply valve to supply the steam generated from the heating tank.  
   
   
       12 . A control method for a washing machine comprising the steps of: 
 when a setting of a user corresponds to a wash course for washing laundry using steam, supplying water into a rotating drum as supplied water, and wetting laundry contained in the rotating drum into wet laundry with the supplied water;    spraying a detergent solution over the wet laundry;    generating steam by a steam generator as generated steam;    injecting the generated steam into the rotating drum, thereby heating the laundry as heated laundry; and    washing the heated laundry.    
   
   
       13 . The control method according to  claim 12 , wherein the rotating drum is rotated in forward and reverse directions in an alternating fashion while the laundry is wetted by the supplied water.  
   
   
       14 . The control method according to  claim 12 , wherein the rotating drum is rotated at a predetermined speed to define an empty space at a central interior of the rotating drum.  
   
   
       15 . The control method according to  claim 14 , wherein the detergent solution is sprayed in the empty space defined in the rotating drum, and a rotating speed of the rotating drum is reduced below the predetermined speed while the detergent solution is being sprayed in a spray of the detergent solution.  
   
   
       16 . The control method according to  claim 15 , wherein the rotating drum is rotated in forward and reverse directions in an alternating fashion for a predetermined time after a completion of the spray of the detergent solution.  
   
   
       17 . The control method according to  claim 16 , wherein the predetermined time spans from a point of time when the rotating drum is stopped to a point of time just before the generated steam is injected into the rotating drum.