Washing machine and method for controlling washing machine

Abstract

A washing machine and a method for controlling a washing machine are provided. The washing machine includes a frame configured to form an exterior, a tub installed in the frame, a drum accommodated in the tub, a washing motor configured to rotate the drum, a drain motor configured to drain water from the tub, a vibration sensor provided in the frame, memory storing one or more computer programs, and a controller coupled to the memory, the vibration sensor, the drain motor, and the washing motor, wherein the one or more computer programs include computer-executable instructions that, when executed by the controller cause the washing machine to drive the drain motor in a stopped state of the washing motor at a start of a spin-drying process, determine a resonant frequency of the frame based on a vibration value measured by the vibration sensor, and control a revolutions per minute (RPM) of the washing motor to avoid the resonant frequency during the spin-drying process.

What is claimed is: 
     
         1 . A washing machine, comprising:
 a frame configured to form an exterior;   a tub installed in the frame;   a drum accommodated in the tub;   a washing motor configured to rotate the drum;   a drain motor configured to drain water from the tub;   a vibration sensor provided in the frame;   memory storing one or more computer programs; and   a controller coupled to the memory, the vibration sensor, the drain motor, and the washing motor,   wherein the one or more computer programs include computer-executable instructions that, when executed by the controller, cause the washing machine to:
 drive the drain motor in a stopped state of the washing motor at a start of a spin-drying process, 
 determine a resonant frequency of the frame based on a vibration value measured by the vibration sensor, and 
 control a revolutions per minute (RPM), of the washing motor to avoid the resonant frequency during the spin-drying process. 
   
     
     
         2 . The washing machine of  claim 1 , wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to change the RPM of the washing motor, based on a difference between a maximum RPM of the washing motor and a resonant band RPM in the spin-drying process being less than or equal to a predetermined RPM. 
     
     
         3 . The washing machine of  claim 1 , wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to change the RPM of the washing motor, based on a predetermined spin-drying intensity in the spin-drying process. 
     
     
         4 . The washing machine of  claim 3 , wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to reduce a maximum RPM of the washing motor, based on a spin-drying intensity of the spin-drying process being less than or equal to a predetermined reference value. 
     
     
         5 . The washing machine of  claim 3 , wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to increase a maximum RPM of the washing motor, based on a spin-drying intensity of the spin-drying process being greater than a predetermined reference value. 
     
     
         6 . The washing machine of  claim 1 , wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to increase acceleration of the washing motor, based on the RPM of the washing motor being increased and a difference from a resonant band RPM reaching a predetermined RPM or less in the spin-drying process. 
     
     
         7 . The washing machine of  claim 1 , further comprising:
 an output interface,   wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to control the output interface to output a message notifying that a time required for the spin-drying process is changed by controlling the RPM of the washing motor.   
     
     
         8 . The washing machine of  claim 1 , further comprising:
 communication circuitry,   wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to control the communication circuitry to transmit information notifying that a time required for the spin-drying process is changed by controlling the RPM of the washing motor to an external device.   
     
     
         9 . The washing machine of  claim 1 , further comprising:
 an input interface,   wherein the one or more computer programs further include computer-executable instructions that, when executed by the controller cause the washing machine to control the washing motor at an existing RPM, based on a command to stop changing the RPM of the washing motor being input to the input interface.   
     
     
         10 . A method performed by a washing machine, the method comprising:
 driving a drain motor configured to drain water from a tub installed in a frame in a stopped state of a washing motor;   measuring a vibration value by a vibration sensor provided in the frame based on the drain motor being driven;   determining a resonant frequency of the frame based on the vibration value; and   controlling a revolutions per minute (RPM), of the washing motor to avoid the resonant frequency.   
     
     
         11 . The method of  claim 10 , further comprising:
 changing the RPM of the washing motor based on a difference between a maximum RPM of the washing motor and a resonant band RPM in a spin-drying process being less than or equal to a predetermined RPM.   
     
     
         12 . The method of  claim 10 , further comprising:
 changing the RPM of the washing motor based on a predetermined spin-drying intensity in the spin-drying process.   
     
     
         13 . The method of  claim 12 , further comprising:
 reducing a maximum RPM of the washing motor based on a spin-drying intensity of the spin-drying process being less than or equal to a predetermined reference value.   
     
     
         14 . The method of  claim 12 , further comprising:
 increasing a maximum RPM of the washing motor based on a spin-drying intensity of the spin-drying process being greater than a predetermined reference value.   
     
     
         15 . The method of  claim 10 , further comprising:
 increasing acceleration of the washing motor, based on the RPM of the washing motor being increased and a difference from a resonant band RPM reaching a predetermined RPM or less in the spin-drying process.   
     
     
         16 . The method of  claim 10 , further comprising:
 outputting, via an output interface of the washing machine, a message notifying that a time required for the spin-drying process is changed by controlling the RPM of the washing motor.   
     
     
         17 . The method of  claim 10 , further comprising:
 transmitting, via communication circuity of the washing machine, information notifying that a time required for the spin-drying process is changed by controlling the RPM of the washing motor to an external device.   
     
     
         18 . The method of  claim 10 , further comprising:
 maintaining an existing RPM of the washing motor, based on a command to stop changing the RPM of the washing motor being input via an input interface of the washing machine.   
     
     
         19 . One or more non-transitory computer-readable storage media storing one or more computer programs including computer-executable instructions that, when executed by one or more processors of a washing machine cause the washing machine to perform operations, the operations comprising:
 driving a drain motor configured to drain water from a tub installed in a frame in a stopped state of a washing motor;   measuring a vibration value by a vibration sensor provided in the frame based on the drain motor being driven;   determining a resonant frequency of the frame based on the vibration value; and   controlling a revolutions per minute (RPM), of the washing motor to avoid the resonant frequency.   
     
     
         20 . The one or more non-transitory computer-readable storage media of  claim 19 , the operations further comprising:
 changing the RPM of the washing motor based on a difference between a maximum RPM of the washing motor and a resonant band RPM in a spin-drying process being less than or equal to a predetermined RPM.