Refrigerator and control method thereof

1 . A control method of a refrigerator that includes a main body, a first door, a second door, a door opening device, a first switch, and a second switch, the main body including a storage compartment, the first door and the second door being rotatably coupled to the main body and being disposed in left and right directions so as to open and close the storage compartment, the door opening device including a motor configured to allow a first push rod and a second push rod to be interlocked with each other and moved in opposite directions, the first push rod being configured to press the first door, the second push rod being configured to press the second door, the first switch and the second switch being configured to receive a user input, the control method comprising:

in response to receiving a user input from the first switch, driving the motor in a forward direction until the first push rod reaches a maximum forward position of the first push rod from a neutral position of the first push rod;

performing at least one of stopping the motor or driving the motor in a reverse direction at a first reference driving speed before a predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod;

driving the motor in the reverse direction at a second reference driving speed until the first push rod returns to the neutral position of the first push rod after the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod; and

changing the predetermined waiting time from a first reference waiting time to a second reference waiting time, less than the first reference waiting time, in response to receiving a user input from the second switch while (a) the motor is driven in the forward direction until the first push rod reaches the maximum forward position of the first push rod from the neutral position of the first push rod or (b) while the at least one of stopping the motor or driving the motor in the reverse direction at the first reference driving speed is performed before the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod.

2 . The control method of claim 1 , wherein

the changing comprises changing the predetermined waiting time from the first reference waiting time to the second reference waiting time in response to receiving the user input from the second switch while the motor is driven in the forward direction until the first push rod reaches the maximum forward position of the first push rod from the neutral position of the first push rod.

3 . The control method of claim 1 , wherein

the performing comprises driving the motor in the reverse direction at the first reference driving speed before the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod, and

the second reference driving speed is greater than the first reference driving speed.

4 . The control method of claim 1 , wherein the performing comprises:

stopping the motor throughout the predetermined waiting time from when the first push rod reaches the maximum forward position of the first push rod.

5 . The control method of claim 1 , wherein the performing comprises:

driving the motor in the reverse direction at the first reference driving speed throughout the predetermined waiting time from when the first push rod reaches the maximum forward position of the first push rod.

6 . The control method of claim 1 , wherein the performing comprises:

stopping the motor for the second reference waiting time from when the first push rod reaches the maximum forward position of the first push rod; and

driving the motor in the reverse direction at the first reference driving speed for a third reference waiting time, which is a difference between the first reference waiting time and the second reference waiting time, after the second reference waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod.

7 . The control method of claim 1 , wherein the first reference waiting time and the second reference waiting time are set by a user.

8 . The control method of claim 1 , further comprising:

in response to receiving the user input from the second switch, driving the motor in the reverse direction at the second reference driving speed until the second push rod reaches a maximum forward position of the second push rod from a neutral position of the second push rod.

9 . The control method of claim 8 , wherein driving the motor in the reverse direction at the second reference driving speed until the first push rod returns to the neutral position of the first push rod, and driving the motor in the reverse direction at the second reference driving speed until the second push rod reaches the maximum forward position of the second push rod from the neutral position of the second push rod are continuously performed.

10 . The control method of claim 1 , wherein

the changing comprises changing the predetermined waiting time in response to receiving the user input from the second switch while the at least one of stopping the motor or driving the motor in the reverse direction at the first reference driving speed is performed before the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod.

11 . The control method of claim 1 , further comprising:

outputting a notification sound through a speaker in response to receiving the user input from the second switch while the motor is driven in the forward direction until the first push rod reaches the maximum forward position of the first push rod from the neutral position of the first push rod.

12 . The control method of claim 1 , further comprising:

outputting a notification sound through a speaker in response to receiving the user input from the second switch while the at least one of stopping the motor or driving the motor in the reverse direction at the first reference driving speed is performed before the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod.

13 . A refrigerator comprising:

a main body including a storage compartment;

a first door and a second door rotatably coupled to the main body and disposed in left and right directions so as to open and close the storage compartment;

a door opening device including a first push rod configured to move so as to press a rear surface of the first door, a second push rod configured to move so as to press a rear surface of the second door, and a motor configured to allow the first push rod and the second push rod to be interlocked with each other and moved in opposite directions, and configured to be driven in a forward and reverse direction;

a first switch configured to receive a user input for opening the first door;

a second switch configured to receive a user input for opening the second door; and

a controller configured to control the motor,

wherein the controller is configured to:

in response to receiving the user input from the first switch, drive the motor in a forward direction until the first push rod reaches a maximum forward position of the first push rod;

perform at least one of stopping the motor or driving the motor in a reverse direction at a first reference driving speed before a predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod;

drive the motor in the reverse direction at a second reference driving speed until the first push rod returns to a neutral position of the first push rod after the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod; and

change the predetermined waiting time from a first reference waiting time to a second reference waiting time, less than the first reference waiting time, in response to receiving the user input from the second switch while (a) the motor is driven in the forward direction until the first push rod reaches the maximum forward position of the first push rod from the neutral position of the first push rod, or (b) while the at least one of stopping the motor or driving the motor in the reverse direction at the first reference driving speed is performed before the predetermined waiting time elapses from when the first push rod reaches the maximum forward position of the first push rod.

14 . The refrigerator of claim 13 , further comprising a speaker configured to output a notification sound,

wherein the controller is configured to output the notification sound through the speaker in response to receiving the user input from the second switch while the motor is driven in the forward direction until the first push rod reaches the maximum forward position of the first push rod from the neutral position of the first push rod.

15 . The refrigerator of claim 13 , wherein the door opening device further comprises a position detection sensor configured to detect a position of at least one from among the first push rod and the second push rod.

16 . The refrigerator of claim 15 , further comprising:

an opening and closing sensor configured to detect whether the first door and the second door are either opened or closed,

wherein the controller is further configured to drive the motor to allow the first push rod and the second push rod to align with each other based on (i) position information of the first push rod and the second push rod that is detected by the position detection sensor, and (ii) opening and closing information of the first door and the second door that is detected by the opening and closing sensor.

17 . The refrigerator of claim 13 , further comprising:

a hinge disposed on a lower end of the main body that is configured to rotatably support the first door; and

a cam unit configured to allow the first door to be closed by its own weight in response to the first push rod moving from the maximum forward position of the first push rod to the neutral position of the first push rod by the motor driven in the reverse direction, the cam unit comprising a door cam disposed on a lower end of the first door; and a hinge cam disposed in the hinge to correspond to the door cam.