Washing machine and control method of the same

Abstract

Disclosed herein are a washing machine and a control method of the same wherein image change or light amount change based on displacement of an object, which is changed depending upon the weight of laundry, is sensed to detect the weight of the laundry, thereby improving reliability in detecting the weight of the laundry.

1 . A washing machine comprising:
 an object whose displacement is changed depending upon weight of laundry;   a sensor module to sense an image, light amount or optical pattern changed depending upon the displacement of the object; and   a controller to detect the weight of the laundry based on the image change or the light amount change.   
     
     
         2 . The washing machine according to  claim 1 , wherein the object is at least one of a suspension spring to support a water tub containing a rotary tub in a suspension manner, the water tub, a damper to dampen vibration generated from the water tub, or combinations thereof. 
     
     
         3 . The washing machine according to  claim 1 , wherein the sensor module comprises a light source to irradiate light to the object, an image sensor to receive the light reflected from the object to create (detect) an image of the object, and an image processor to perform a comparison between a reference image, which is an image before the laundry is put into the rotary tub, and a current image, which is an image after the laundry is put into the rotary tub, to sense image change of the object. 
     
     
         4 . The washing machine according to  claim 3 , wherein the image processor sets a mask window of a predetermined size in the reference image, calculates correlation coefficient values while moving the mask window with respect to the entirety of the current image by an arbitrary pixel unit, calculates a displacement value of the mask window with respect to a position having the largest correlation coefficient value, and recognizes the calculated displacement value as an image change value of the object. 
     
     
         5 . The washing machine according to  claim 4 , wherein, if the object is a damper, the sensor module is provided at the damper to sense image change of the damper depending upon displacement of the damper. 
     
     
         6 . The washing machine according to  claim 5 , wherein the damper comprises a cylinder and a piston mounted in the cylinder in an advancing and retreating manner, and
 the sensor module is provided at the cylinder or the piston to sense image change of the cylinder or the piston depending upon displacement of the cylinder or the piston.   
     
     
         7 . The washing machine according to  claim 4 , wherein, if the object is a water tub, the sensor module is provided at a housing of the washing machine corresponding to the water tub to sense image change of the water tub depending upon displacement of the water tub. 
     
     
         8 . The washing machine according to  claim 7 , wherein the sensor module senses image change of the water tub depending upon vertical displacement of the water tub. 
     
     
         9 . The washing machine according to  claim 4 , wherein, if the object is a suspension spring, the sensor module is provided at the suspension spring to sense image change of the suspension spring depending upon displacement of the suspension spring. 
     
     
         10 . The washing machine according to  claim 1 , wherein
 the object is a water tub,   the sensor module comprises a light emitting unit to emit light and a light receiving unit to receive the light emitted from the light emitting unit, the sensor module being disposed such that an amount of the light, corresponding to displacement of the water tub, received by the light receiving unit is changed, and   the controller detects the weight of the laundry based on the change in the amount of the light received by the light receiving unit.   
     
     
         11 . The washing machine according to  claim 10 , wherein the light emitting unit comprises a light source to emit light and a lens to disperse the light emitted from the light source such that the light is irradiated to the light receiving unit in parallel. 
     
     
         12 . The washing machine according to  claim 1 , wherein
 the object is a water tub,   the sensor module comprises a light source unit to emit light and an optical pattern sensor to receive the light emitted from the light source unit, the sensor module being disposed such that an optical pattern, corresponding to displacement of the water tub, sensed by the optical pattern sensor is changed, and   the controller detects the weight of the laundry based on the optical pattern sensed by the optical pattern sensor.   
     
     
         13 . A control method of a washing machine having an object whose displacement is changed depending upon weight of laundry, the control method comprising:
 sensing image change of the object depending upon the displacement of the object; and   detecting the weight of the laundry based on the sensed image change of the object.   
     
     
         14 . The control method according to  claim 13 , wherein the object is at least one of a suspension spring to support a water tub containing a rotary tub in a suspension manner, the water tub, a damper to dampen vibration generated from the water tub, or combinations thereof. 
     
     
         15 . The control method according to  claim 14 , wherein sensing image change of the object comprises setting a mask window of a predetermined size in a reference image, which is an image of the object before the laundry is put into the rotary tub, calculating correlation coefficient values while moving the mask window with respect to the entirety of a current image, which is an image of the object after the laundry is put into the rotary tub, by an arbitrary pixel unit, and calculating a displacement value of the mask window with respect to a position having the largest correlation coefficient value. 
     
     
         16 . The control method according to  claim 15 , wherein detecting the weight of the laundry comprises recognizing a weight value corresponding to the displacement value of the mask window as a weight value of the laundry. 
     
     
         17 . A control method of a washing machine having an object whose displacement is changed depending upon weight of laundry, the control method comprising:
 sensing images of the object before and after the laundry is put into a rotary tub;   sensing position change of a common portion between the sensed images of the object; and   detecting the weight of the laundry based on the sensed position change of the common portion.   
     
     
         18 . The control method according to  claim 17 , wherein sensing position change of the common portion comprises setting a mask window of a predetermined size in a reference image, which is an image of the object before the laundry is put into the rotary tub, calculating correlation coefficient values while moving the mask window with respect to the entirety of a current image, which is an image of the object after the laundry is put into the rotary tub, by an arbitrary pixel unit, and calculating a displacement value of the mask window with respect to a position having the largest correlation coefficient value. 
     
     
         19 . The control method according to  claim 18 , wherein the object is at least one of a suspension spring to support a water tub containing the rotary tub in a suspension manner, the water tub, a damper to dampen vibration generated from the water tub, or combinations thereof. 
     
     
         20 . A control method of a washing machine having a sensor module comprising a light emitting unit to emit light and a light receiving unit to receive the light emitted from the light emitting unit, and a water tub whose displacement is changed depending upon weight of laundry, the sensor module being disposed such that an amount of the light, corresponding to displacement of the water tub, received by the light receiving unit is changed, the control method comprising:
 sensing light amount change depending upon the displacement of the water tub; and   detecting the weight of the laundry based on the sensed light amount change.   
     
     
         21 . A control method of a washing machine having a sensor module comprising a light source unit to emit light and an optical pattern sensor to receive the light emitted from the light source unit, and a water tub whose displacement is changed depending upon weight of laundry, the sensor module being disposed such that an optical pattern, corresponding to displacement of the water tub, sensed by the optical pattern sensor is changed, the control method comprising:
 sensing optical pattern change depending upon the displacement of the water tub; and   detecting the weight of the laundry based on the sensed optical pattern change.   
     
     
         22 . A method for a washing machine having an object which changes responsive to a weight of laundry, the method comprising:
 sensing a change in an image of the object; and   determining the weight of the laundry responsive to the change.