Ice maker and refrigerator including the same

Abstract

An ice tray may include a control box; a motor unit installed in the control box, and generating a rotational force; a gear group receiving the rotating force of the motor unit, and including one or more gears having a gear ratio through which a rotational speed by the rotational force is changed, and an output unit engaged with the one or more gears and transferring a speed-changed rotation to the outside of the control box; and an ice tray having one side connected to a connection shaft extended from the output unit of the gear group, and rotated by a final number of rotations transferred through the output unit, where the one side of the ice tray has a larger rotation angle than the other side of the ice tray. The output unit may receive the rotational force through one or more gears, and include first and second output units which are formed as different modules so as to be rotated through two gear ratios. The rotation centers of the first and second output units may be positioned on the same axis, and the first and second output units are formed in different rotation sections.

1 . An ice maker that is controlled by a signal received from a refrigerator controller installed in a refrigerator, the ice maker comprising:
 a motor unit generating a rotational force corresponding to the signal;   a driving unit comprising a gear group rotated by the motor unit; and   an ice tray twisted by an operation of the gear group, and configured to contain water therein to make ice,   wherein a rotational speed of the ice tray is changed one or more times in a rotation section where the ice tray is twisted by the rotational force corresponding to the signal or a rotational speed difference formed during engagement between gears in the gear group.   
     
     
         2 . The ice maker of  claim 1 , wherein the gear group comprises:
 one or more gears receiving the rotational force of the motor unit, and having a gear ratio to change the rotational speed by the rotational force; and   an output unit engaged with the one or more gears, and transferring a speed-changed rotation to the outside of a control box.   
     
     
         3 . The ice maker of  claim 2 , wherein the output unit comprises first and second output units receiving the rotational force of the motor unit through the one or more gears, and formed as different modules so as to be rotated at two gear ratios,
 wherein the rotation centers of the first and second output units are positioned on a same axis, rotation sections in which the first and second output units are engaged with the respective gears are formed as different sections, the first and second output units form different pitch circles, and the engagement of the first output unit and the engagement of the second output unit is sequentially performed.   
     
     
         4 . The ice maker of  claim 2 , wherein the motor unit comprises one or more of an arrangement in which a motor shaft is extended in an opposite direction of a connection shaft of the output unit and an arrangement in which the motor shaft is eccentrically located with respect to a body of the motor unit. 
     
     
         5 . The ice maker of  claim 2 , wherein in a section where the first output unit is rotated in engagement with the corresponding gear, the ice tray is rotated at a higher speed than in a section where the second output unit is rotated in engagement with the corresponding gear, and
 in the section where the second output unit is rotated in engagement with the corresponding gear, the ice tray is rotated at a higher torque than in the section where the first output unit is rotated in engagement with the corresponding gear.   
     
     
         6 . The ice maker of  claim 5 , wherein one side of the ice tray is rotated when the first and second output units are rotated in engagement with the respective gears, and another side of the ice tray is rotated when only the first output unit is rotated in engagement with the corresponding gear. 
     
     
         7 . The ice maker of  claim 2 , wherein among the one or more gears of the gear group, gears engaged with the output unit have a free rotation section in which the gears are freely rotated before and after the gears are engaged with the output unit in different rotation sections. 
     
     
         8 . The ice maker of  claim 2 , wherein among gear teeth of the second output unit, gear teeth positioned in a start section where the engagement of the first output unit is switched to the engagement of the second output unit have a smaller height than the other gear teeth. 
     
     
         9 . The ice maker of  claim 1 , wherein the gear group comprises:
 a first gear part formed on a connection part installed at one side of the ice tray, rotated by a predetermined length through a rotational force based on the signal, and formed along the rotation direction of the connection part; and   a second gear part installed on a motor shaft of the motor unit, formed at a position corresponding to the first gear part, and rotated in engagement with the first gear part,   wherein the first gear part comprises a plurality of gears which are formed at different radiuses from a rotation center of the connection part rotated by the rotational force, and have rotation sections separated from each other, and   the second gear part comprises a plurality of gears corresponding to the respective gears of the first gear part.   
     
     
         10 . The ice maker of  claim 1 , wherein the gear group further comprises a third gear part positioned between the first and second gear parts so as to transfer the rotational force to the first gear part, and including a first middle gear engaged with the first gear part and a second middle gear engaged with the second gear part,
 wherein the first and second middle gears of the third gear part are disposed to compensate for different rotation directions of the first and second gear parts, and the rotation centers of the first and second middle gears are positioned on the same axis.   
     
     
         11 . The ice maker of  claim 9 , wherein the plurality of gears formed on the connection part comprise first and second engagement gears,
 wherein sections in which the first and second engagement gears are formed to have different lengths, and the first engagement gear which is engaged with the motor shaft later than the second engagement gear has a shorter length than the second engagement gear.   
     
     
         12 . The ice maker of  claim 9 , wherein the plurality of gears formed on the connection part comprise first and second engagement gears,
 the first engagement gear formed at a larger radius distance than the second engagement gear on the connection part is engaged with the motor shaft later than the second engagement gear, and   a difference between the radius distances forms a section in which the rotation of the connection part is changed from a high speed to a low speed.   
     
     
         13 . The ice maker of  claim 1 , wherein the different rotational speeds of the connection part are decided according to one or more of a rotational speed of the motor shaft and a gear ratio of the middle gear. 
     
     
         14 . The ice maker of  claim 1 , wherein when the ice tray is close to a stopper located at one side of the ice maker, the rotation of the motor unit is pulse-controlled to increase a torque of the ice tray. 
     
     
         15 . The ice maker of  claim 1 , wherein the driving unit comprises:
 a drive configured to convert the electrical signal received from the signal receiving unit into rotation information; and   the motor unit configured to receive the rotation information from the drive and rotate in response to the rotation information.   
     
     
         16 . The ice maker of  claim 15 , wherein the ice maker performs transmission/reception with the refrigerator controller through a plurality of communication lines,
 wherein during the reception operation, the ice maker receives the signal from a cross output unit that selectively cross-transmits or non-cross-transmits the signal through the plurality of lines.   
     
     
         17 . The ice maker of  claim 16 , wherein the signal comprises a pulse signal or a digital signal, and the rotation information is decided through direction information contained in the signal transmitted by the cross output unit. 
     
     
         18 . The ice maker of  claim 15 , wherein the controller receives a control waveform to control the driving unit. 
     
     
         19 . A refrigerator comprising:
 a refrigerator controller positioned in the refrigerator;   a signal transmitting unit included in the refrigerator controller, and transmitting a signal;   a cross output unit included in the refrigerator controller, and transmitting the electrical signal received from the signal transmitting unit through a plurality of lines, wherein the cross output unit selectively cross-transmits or non-cross-transmits the electrical signal through the plurality of lines according to control of the refrigerator control unit; and   an ice maker,   wherein the ice maker comprises:   a signal receiving unit receiving the electrical signal transmitted from the cross output unit;   a driving unit comprising: a drive configured to convert the electrical signal received from the signal receiving unit into rotation information; and a motor unit configured to receive the rotation information from the drive and rotate in response to the rotation information; and   an ice tray connected to the motor unit, rotated by the rotation of the motor unit, disposed in sub-zero temperatures in the refrigerator, and having water contained therein to make ice,   wherein the motor unit comprises a stepping motor, and   the rotation information comprises one or more of a rotational speed, a rotation direction, a rotation angle and a torque.   
     
     
         20 . A refrigerator comprising the ice maker of  claim 1 .