Patent Publication Number: US-10775095-B2

Title: Refrigerator

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage application under 35 U.S.C. § 371 of International Application No. PCT/KR2017/000476, filed Jan. 13, 2017, which claims the benefit of Korean Application No. 10-2016-0004831, filed on Jan. 14, 2016. The disclosures of the prior applications are incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The present invention relates to a refrigerator and, more particularly, to a refrigerator having improved convenience of use, the refrigerator being of a type in which two doors arranged side by side are used to open a single storage compartment. 
     BACKGROUND ART 
     In general, a refrigerator is an apparatus that may keep food fresh for a certain duration by cooling a storage compartment (a freezing compartment or a refrigerating compartment) while repeating a freezing cycle. 
     The refrigerator includes a compressor, which compresses refrigerant, circulating through a freezing cycle, into high-temperature and high-pressure refrigerant. The refrigerant, compressed in the compressor, cools air while passing through a heat exchanger, and the cooled air is supplied to the freezing compartment or the refrigerating compartment. 
     The refrigerator may have a configuration in which the freezing compartment is at the upper side and the refrigerating compartment is at the lower side. A side-by-side-type refrigerator may be configured such that the freezing compartment and the refrigerating compartment are arranged side by side on the left and right sides, respectively. 
     In addition, there is another type of refrigerator in which a single storage compartment, provided at the upper side or the lower side, may be opened by two doors, which are arranged side by side. 
     In the case where two doors are arranged side by side to open or close a single storage compartment, a pillar is installed on one of the two doors. The pillar is provided at any one of the two doors, and functions to increase the sealing efficiency of the storage compartment by coming into contact with the two doors when the two doors seal the storage compartment. 
     In the related art, in order to rotate the pillar, an inner case of the refrigerator is generally provided with a structure including a protrusion and a guide groove to guide the rotation of the pillar. 
     According to the related art, the structure for guiding the rotation of the pillar needs to protrude downwards from the upper side of the inner case, and thus a user experiences inconvenience when using the storage compartment. 
     In addition, in the state in which the door provided with the pillar seals the storage compartment, the pillar may block the path along which a drawer installed in the refrigerator moves because the pillar is moved away and unfolded from the corresponding door. Therefore, in the case where two drawers are arranged parallel to each other, the two drawers must have different widths. 
     In addition, in consideration of the fact that the pillar is in the unfolded state, in the case where a basket is installed in the door so as to be rotated together with the door, the basket requires a gently curved corner portion so as not to come into contact with the pillar, which may result in a reduction in the storage capacity of the basket. 
     DISCLOSURE 
     Technical Problem 
     An object of the present invention devised to solve the problem is to provide a refrigerator having improved convenience of use, the refrigerator being of a type in which two doors arranged side by side are used to open a single storage compartment. 
     Technical Solution 
     The present invention provides a refrigerator including a cabinet including a storage compartment, an inner case defining the external appearance of the storage compartment, a first door rotatably installed to the cabinet to open or close a portion of the storage compartment, a second door including a pillar configured to be rotated so as to come into contact with the first door, the second door being rotatably installed to the cabinet to open or close the remaining portion of the storage compartment, and a transmission unit provided in the inner case, the transmission unit being configured to sense rotation of the second door to guide rotation of the pillar, wherein the pillar is disposed so as to be spaced apart from the top wall of the inner case and the bottom wall of the inner case in order to prevent contact with the inner case in the state in which the second door seals the storage compartment, and the transmission unit includes a lifting guide unit that is lowered when the pillar approaches the lifting guide unit and that comes into contact with the pillar in the state in which the pillar is unfolded. 
     The pillar may include a pillar protrusion that protrudes from the upper side thereof to an extent that prevents contact with the ceiling of the inner case, and the pillar protrusion may guide the folding of the pillar through contact with the lifting guide unit. 
     The pillar protrusion may be formed so as to be located on the rear side of the lifting guide unit when the lifting guide unit is lowered. 
     The pillar may be provided at an upper side thereof with a first pillar magnetic member, and the lifting guide unit may be provided with a steel plate member that magnetically interferes with the first pillar magnetic member. 
     The lifting guide unit may include a case enveloping the steel plate member and an elastic member elastically supporting the case in an upward direction. 
     When the pillar approaches the lifting guide unit, the elastic member may be extended, and the case may be lowered. 
     The transmission unit may include a rotary arm that is rotated based on whether the first door is rotated. 
     The rotary arm may be provided at one end thereof with a first magnetic member, and may be provided at the opposite end thereof with a second magnetic member. 
     The rotary arm may have a rotation center located between the first magnetic member and the second magnetic member. 
     The first door may be provided at an upper side thereof with a first door magnetic member that magnetically interferes with the first magnetic member, and may be provided on a lateral surface thereof with a second door magnetic member, and the pillar may be provided on a lateral surface thereof with a second pillar magnetic member that magnetically interferes with the second door magnetic member. 
     The pillar may be disposed so as to be rotatable in the state in which the first door opens the storage compartment and the second door seals the storage compartment. 
     When the first door and the second door seal the storage compartment, the pillar may come into contact with the first door and the second door. 
     The refrigerator may further include a first drawer disposed near the first door and a second drawer disposed near the second door, and the first drawer and the second drawer may have the same width. 
     The first drawer and the second drawer may be disposed in the same horizontal plane, and may be pulled outwards independently of each other. 
     The first door and the second door may have the same width. 
     Advantageous Effects 
     According to the present invention, a structure for rotating a pillar does not protrude toward a storage compartment, which may result in an increase in the capacity of the storage compartment and may resolve inconvenience caused to a user due to the protruding configuration. 
     In addition, in the state in which only a door having a pillar seals a storage compartment and an opposite door opens the storage compartment, the pillar is in the folded state, and therefore does not interfere with a drawer installed near the opposite door when the drawer is pulled outwards. This may allow a pair of drawers having the same width to be installed at both sides. 
     In addition, in the state in which only the door having the pillar seals the storage compartment and the opposite door opens the storage compartment, the pillar is in the folded state, and therefore does not interfere with a basket installed in the opposite door when the opposite door is rotated. This may allow the basket to have a sharp corner, thus increasing the storage capacity of the basket. 
     In addition, when two doors are opened at the same time, the pillar may be folded. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a front view of a refrigerator according to an embodiment of the present invention. 
         FIG. 2  is a view illustrating major parts according to the embodiment. 
         FIG. 3  is a view for explaining a pillar-fixing unit according to the embodiment. 
         FIGS. 4A to 4C  are views for explaining the state in which a first door is being closed when a second door is in the closed state. 
         FIGS. 5A to 5C  are views for explaining the state in which the first door is being opened when the second door is in the closed state. 
         FIGS. 6A to 6C  are views for explaining the state in which the second door is being opened when the first door is in the closed state. 
         FIGS. 7A to 7C  are views for explaining the state in which the second door is being closed when the first door is in the closed state. 
         FIG. 8  is a cross-sectional view illustrating the operation of a lifting guide unit. 
         FIGS. 9A to 9C  are views for explaining the state in which the first door and the second door are both being opened at the same time. 
         FIGS. 10A to 10C  are side views of  FIGS. 9A to 9C . 
     
    
    
     BEST MODE 
     Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings in order to concretely realize the object as set forth above. 
     In the drawings, the sizes or shapes of elements may be exaggerated for clarity and convenience of description. Furthermore, terms particularly defined in consideration of construction and operation of the present invention can be changed according to the custom or intention of users or operators. Therefore, definition of the terms should be made according to the overall disclosures set forth herein. 
       FIG. 1  is a front view of a refrigerator according to an embodiment of the present invention. 
     Referring to  FIG. 1 , the refrigerator according to the embodiment includes a cabinet  1 , which defines the external appearance of the refrigerator. 
     The cabinet  1  has a storage compartment  2  in which food may be stored. 
     The external appearance of the storage compartment  2  may be defined by an inner case  10 , which is provided inside the cabinet  1 . The inner case  10  may include a top wall  12  and a bottom wall  14 , which form the inner surface of the storage compartment  2 , and the front side of the storage compartment  2  may be open in order to allow a user to access the storage compartment  2  through the front side of the storage compartment  2 . The top wall  12  defines a ceiling  12  of the storage compartment  2  or the inner case  10 . 
     The cabinet  1  is provided at the front side thereof with a first door  20 , which is rotatably installed to the cabinet  1  so as to open or close a portion of the storage compartment  2 , and a second door  40 , which is rotatably installed to the cabinet  1  so as to open or close the remaining portion of the storage compartment  2 . At this time, when the first door  20  and the second door  40  close the front side of the storage compartment  2 , the entire storage compartment  2  may be sealed. 
     A pillar  100  may be rotatably installed on the second door  40  so as to come into contact with the first door  20 . The pillar  100  may generally have a rectangular parallelepiped shape, and may be coupled to the second door  40  so as to be rotated relative to the second door  40 . At this time, the pillar  100  may be positioned such that the rotated angle thereof relative to the second door  40  varies based on, for example, the angle by which the second door  40  is rotated relative to the storage compartment  2 , or based on whether the first door  20  opens or closes the storage compartment  2 . 
     The pillar  100  has a length that is shorter than the distance between the top wall  12  and the bottom wall  14  of the inner case  10  so as not to come into contact with the top wall  12  and the bottom wall  14 . That is, even when the second door  40  is rotated and seals the storage compartment  2 , the pillar  100  does not come into contact with either the top wall  12  or the bottom wall  14 . Any element that may restrict the rotation of the pillar  100  is not located at the top wall  12  or the bottom wall  14 , and thus the inner case  10  may have a structural shape in which each of the top wall  12  and the bottom wall  14  is generally formed in a single planar shape. 
     The pillar  100  is provided at the upper side thereof with a pillar protrusion  130 . The pillar protrusion  100  protrudes to an extent that prevents contact with the top wall  12 , i.e. the ceiling  12 . 
     The first door  20  may include a door dike  22 , which defines the rear appearance of the first door  20 . In addition, the second door  40  may include a door dike  42 , which defines the rear appearance of the second door  40 . 
     Baskets  44  and  24  may respectively be installed to the door dikes  42  and  22 , and may be used to store various shapes of food therein. At this time, the basket  24 , which is installed to the first door  20 , which is not provided with the pillar  100 , does not interfere with the pillar  100  when the first door  20  is rotated. Therefore, the basket  24  may have a sharp corner. Accordingly, the basket  24  may store an increased amount of food compared to a basket having a rounded corner. 
     The storage compartment  2  may be provided with a first drawer  34 , located near the first door  20 , and a second drawer  32 , located near the second door  40 . At this time, the first drawer  34  and the second drawer  32  may be disposed in the same horizontal plane. That is, the first drawer  34  and the second drawer  32  may be arranged on the left and right sides, respectively, at the same height within the storage compartment  2 . The first drawer  34  and the second drawer  32  may be pulled outwards independently of each other. 
     The first drawer  34  and the second drawer  32  may have the same width. That is, the first drawer  34  and the second drawer  32  may have the same storage capacity, and may be replaced with each other. Assuming that the first drawer  34  and the second drawer  32  have different widths, and thus different shapes, the first drawer  34  and the second drawer  32  need to be manufactured differently, which may inevitably increase manufacturing costs. On the other hand, assuming that the two drawers have the same shape, manufacturing costs thereof may be advantageously reduced. 
     In the embodiment of the present invention, the function described above may be implemented because, when the first door  20  is opened and the first drawer  34  is pulled outwards in the state in which the second door  40  seals the storage compartment  2 , the pillar  100  is not located in the path along which the first drawer  34  is pulled outwards. The reason why the pillar is not located in the path will be described in detail later with reference to other drawings. 
     Meanwhile, in the embodiment of the present invention, the first door  20  and the second door  40  may have the same width. Thus, the first door  20  and the second door  40  may share some of the production processes thereof, which may reduce the production costs of the doors. The reason for this will be described later with reference to other drawings. 
     A transmission unit  1000  may be provided inside the top wall  12  of the inner case  10 , and may serve to rotate the pillar  100  under a specific condition. 
     In the embodiment of the present invention, the transmission unit  1000  may be installed inside the top wall  12  so as not to be exposed to a user. 
     Accordingly, a portion of the top wall  12  in which the transmission unit  1000  is installed and a neighboring portion thereof in which the transmission unit  1000  is not installed may be formed at the same height. That is, the portion in which the transmission unit  1000  is installed and the remaining portion adjacent thereto are formed in the same plane, and thus it is impossible for a user to recognize whether the transmission unit  1000  is installed inside the inner case  10  merely by viewing the inner case  10 . Therefore, it may be possible to prevent problems such as inconvenience that may be caused to a user due to the configuration in which the portion in which the transmission unit  1000  is installed protrudes, a reduction in the storage capacity, or the like. 
       FIG. 2  is a view illustrating major parts according to the embodiment. 
     Referring to  FIG. 2 , the embodiment of the present invention may be configured such that the pillar  100  is rotated in a manner such that the transmission unit  1000  senses the position of a magnetic member installed in the first door  20  and exerts an influence on a magnetic member installed in the pillar  100 . 
     The transmission unit  1000 , installed inside the top wall  12  of the inner case  10 , may sense the rotation of the second door  40 , and may guide the rotation of the pillar  100 . 
     The transmission unit  1000  includes a space portion  1100 , which defines an empty space therein, a rotary arm  1200 , which is rotatably provided in the space portion  1100 , and an elastic member  1300 , which applies force to the rotary arm  1200  so that the rotary arm  1200  returns to a prescribed position when external force applied to the rotary arm  1200  is eliminated. 
     The space portion  1100  may provide a path along which the rotary arm  1200  is rotated when an external force is applied to the rotary arm  1200 , particularly, when the rotary arm  1200  is influenced by a magnetic force. 
     Here, the space portion  1100  may be a space formed inside a separately provided housing, or may be a certain space formed inside the top wall  12  of the inner case  10 . 
     The rotary arm  1200  may include a rotation center portion  1230 , which is disposed at one side inside the space portion  1100  and about which the rotary arm  1200  rotates. The rotation center portion  1230  may be coupled to the wall surface, which is the outer circumferential surface of the space portion  1100 , so as to enable the rotary arm  1200  to rotate thereabout. 
     The rotary arm  1200  may include a first arm  1210  and a second arm  1220 , which extend from the rotation center portion  1230 . 
     The first arm  1210  may be provided at one end thereof with a first magnetic member  1212  having a magnetic force, and the second arm  1220  may be provided at one end thereof with a second magnetic member  1222  having a magnetic force. The first magnetic member  1212  and the second magnetic member  1222  may be disposed opposite each other about the rotation center portion  1230  of the rotary arm  1200  so as to secure sufficient rotational force when the rotary arm  1200  rotates. 
     Here, the second arm  1220  may have a length that is shorter than the length of the first arm  1210 . Even when the magnetic force that is applied to the first magnetic member  1212  is less than the magnetic force that is applied to the second magnetic member  1222 , the rotary arm  1200  may be rotated by the first magnetic member  1212 . This is because the first arm  1210  generates a relatively large rotational force due to the relatively long length thereof even when the force applied to the first magnetic member  1212  is relatively small. 
     A fixing member  1104  may be provided in the space portion  1100 , and the second arm  1220  may be provided with a fixing protrusion  1240 . The fixing protrusion  1240  may be formed on the surface of the second arm  1220  that faces the fixing member  1104 . The fixing member  1104  and the fixing protrusion  1240  may be fixed by an elastic member  1300 . At this time, the elastic member  1300  may have restoring force by which it is extended when an external force is applied thereto and is restored to the original length thereof when the external force is eliminated. 
     That is, in the state in which the rotary arm  1200  has been rotated in the counterclockwise direction by the external force applied thereto, the elastic member  1300  may provide the restoring force to the rotary arm  1200  so that the rotary arm  1200  can be rotated in the clockwise direction when the external force is eliminated. 
     The transmission unit  1000  includes a lifting guide unit  1400 , which is lowered when the pillar  100  approaches the lifting guide unit  1400 . As shown in  FIG. 2 , in the state in which the lifting guide unit  1400  has been raised, the bottom surface of the lifting guide unit  1400  may be disposed in the same plane as the bottom surface of the transmission unit  1000 , or may be disposed higher than the bottom surface of the transmission unit  1000 . Therefore, when the pillar  100  is distant from the transmission unit  1000 , a user may not recognize the presence of the lifting-guide unit  1400 . 
     The first door  20  may be provided with a first door magnetic member  26 , which magnetically interferes with the first magnetic member  1212 . The first door magnetic member  26  and the first magnetic member  1212  may be arranged such that the surfaces thereof from which magnetic force is generated face each other so as to cause greater magnetic interference therebetween. 
     In addition, the pillar  100  may be provided with a first pillar magnetic member  110 , which magnetically interferes with the second magnetic member  1222 . The first pillar magnetic member  110  and the second magnetic member  1222  may be arranged such that the surfaces thereof from which magnetic force is generated face each other so as to cause greater magnetic interference therebetween. 
     Meanwhile, the pillar protrusion  130  may be located above the first pillar magnetic member  110 . The pillar protrusion  130  may include an outer side, which is formed in the shape of an arc, and an inner side, which is formed in the shape of an arc that has a smaller radius than the arc of the outer side. 
     The inner side of the pillar protrusion  130  may be formed so as to surround the rear surface of the lifting guide unit  1400 . The pillar protrusion  130  is not disposed on the front surface of the lifting guide unit  1400 , but is disposed on the rear surface of the lifting guide unit  1400 . Therefore, the lifting guide unit  1400  may not move independently of the pillar protrusion  130 , but may be caught by the pillar protrusion  130 , thereby restricting the rotation direction of the pillar  100 . That is, in the state in which the lifting guide unit  1400  is in contact with the pillar protrusion  130 , the pillar  100  is rotated only in the counterclockwise direction on the basis of  FIG. 2 , and cannot be rotated in the clockwise direction. That is, in the state in which the lifting guide unit  1400  is caught by the pillar protrusion  130 , the pillar  100  may be folded. 
     In addition, when the pillar  100  is rotated so as to be folded by the respective magnetic members, the pillar protrusion  100  is not caught by the lifting guide unit  1400 , and thus the pillar  100  may be folded without being restricted by the lifting guide unit  1400 . 
     The first door  20  may be provided on the lateral surface thereof with a second door magnetic member  28 , and the pillar  100  may be provided on the lateral surface thereof with a second pillar magnetic member  120 . The second door magnetic member  28  may magnetically interfere with the second pillar magnetic member  120 . The second pillar magnetic member  120  and the second door magnetic member  28  may be arranged such that the surfaces thereof from which magnetic force is generated face each other so as to cause greater magnetic interference therebetween. 
     The first magnetic member  1212  and the first door magnetic member  26 , the second magnetic member  1222  and the first pillar magnetic member  110 , and the second door magnetic member  28  and the second pillar magnetic member  120  may respectively be configured to use repulsive magnetic force. That is, the first magnetic member  1212  and the first door magnetic member  26 , the second magnetic member  1222  and the first pillar magnetic member  110 , and the second door magnetic member  28  and the second pillar magnetic member  120  may respectively be arranged so as to be influenced by the repulsive magnetic force. 
     The use of repulsive magnetic force may overcome shortcomings of use of attractive magnetic force, which requires a large force to separate magnets attracted to each other and which is more sensitive to tolerance variation, because when an attractive magnetic force is generated between two magnets, the magnets try to move so that the magnetic centers thereof coincide with each other. 
       FIG. 3  is a view for explaining a pillar-fixing unit according to the embodiment. 
     Referring to  FIG. 3 , the pillar  100  is rotatably provided at the second door  40 . 
     The pillar  100  may be rotatably installed to a pillar-fixing unit  50  provided at the second door  40 . 
     The pillar-fixing unit  50  may apply force to the pillar  100  in both directions (in the direction in which the pillar is folded and in the direction in which the pillar is unfolded). The pillar-fixing unit  50  may be composed of various elements such as a spring, a rotary cam assembly, or the like. 
     That is, in the state in which the pillar  100  is rotated at a certain angle, the pillar-fixing unit may induce the pillar to be folded, and in the state in which the pillar  100  is rotated at another angle, the pillar-fixing unit may induce the pillar to be unfolded. 
     Because the pillar-fixing unit  50  applies force in the direction in which the pillar  100  is folded, when the second door  40  is opened in the state in which the pillar  100  is folded, the pillar  100  may be prevented from flapping. Because the pillar-fixing unit  50  continuously applies force so that the pillar  100  remains folded, it may be possible to prevent the occurrence of vibration or noise attributable to undesired movement of the pillar  100 . 
     In addition, because the pillar-fixing unit  50  applies force in the direction in which the pillar  100  is folded, when the first door  20  is opened, the pillar-fixing unit  50  may provide auxiliary force for folding the pillar  100 . When the first door  20  is opened in the state in which the second door  40  closes the storage compartment  2 , the pillar  100  needs to be changed to the folded state, which will be described later. 
     In addition, because the pillar-fixing unit  50  also applies force in the direction in which the pillar  100  is unfolded, it may enable the pillar  100  to be unfolded and to come into contact with the first door  20 , so that the storage compartment  2  can be substantially sealed. 
     For convenience of illustration, in  FIGS. 4A to 7C , the lifting guide unit  1400  is omitted from the transmission unit  1000 . Also, in the following description, a detailed explanation of the operation of the lifting guide unit  1400  will be omitted. 
       FIGS. 4A to 4C  are views for explaining the state in which the first door is being closed when the second door is in the closed state. 
     Referring to  FIGS. 4A to 4C , when the second door  40  is in the closed state and the first door  20  is in the opened state, a user may rotate the first door  20  to close the same. 
     In the state in which the second door  40  seals the storage compartment  2 , when the first door  20  is rotated in order to also seal the storage compartment  2 , the pillar  100  needs to be rotated from the folded state to the unfolded state. 
     As shown in  FIG. 4A , when the first door  20  is rotated and approaches the transmission unit  1000 , magnetic interference occurs between the first magnetic member  1212  and the first door magnetic member  26 . At this time, a repulsive force is generated between the first magnetic member  1212  and the first door magnetic member  26 , and thus the rotary arm  1200  is rotated in the counterclockwise direction about the rotation center portion  1230 . 
     As shown in  FIG. 4B , as the first door  20  is closed further, the rotary arm  1200  is continuously rotated by the first magnetic member  1212  and the first door magnetic member  26 , and magnetic interference occurs between the second magnetic member  1222  and the first pillar magnetic member  110 . At this time, a repulsive force is also generated between the second magnetic member  1222  and the first pillar magnetic member  110 . 
     Meanwhile, when the rotary arm  1200  is further rotated in the counterclockwise direction from the state of  FIG. 4B , the second magnetic member  1222  is located on the left side of the first pillar magnetic member  110 , and the pillar  100  may be unfolded by the repulsive force generated between the second magnetic member  1222  and the first pillar magnetic member  110 . Particularly, the second magnetic member  1222  may be located on the left side of a rotation center  102  of the pillar  100 . The left side of the rotation center  102  of the pillar  100  is a position at which a repulsive force is provided so that the pillar  100  can be rotated in the clockwise direction about the rotation center  102 . 
     This is because, when the second magnetic member  1222  is located on the left side of the first pillar magnetic member  110 , the second magnetic member  1222  applies a repulsive force to the first pillar magnetic member  110 , and thus the pillar  100  is rotated away from the second magnetic member  1222 , i.e. is rotated in the direction in which the pillar  100  is unfolded. 
     As shown in  FIG. 4C , when the first door  20  seals the storage compartment  2 , the first magnetic member  1212  is continuously influenced by the first door magnetic member  26 , whereby the rotary arm  1200  is rotated in the counterclockwise direction and the elastic member  1300  is extended. 
     Due to the repulsive force generated between the first pillar magnetic member  110  and the second magnetic member  1222 , the pillar  100  may come into contact with the first door  20  and the second door  40 , and may seal the storage compartment  2 . At this time, the repulsive force generated between the first pillar magnetic member  110  and the second magnetic member  1222  is greater than the force generated by the pillar-fixing unit  50 , and thus it may overcome the force that is applied from the pillar-fixing unit  50  to the pillar  100  in order to fold the pillar  100 . 
     In the state of  FIG. 4C , the lifting guide unit  1400  may be lowered, and may be changed to the state of being caught by the pillar protrusion  130 . A detailed explanation thereof will be made later with reference to  FIGS. 8 to 10C . 
       FIGS. 5A to 5C  are views for explaining the state in which the first door is being opened when the second door is in the closed state. 
     Referring to  FIGS. 5A to 5C , in the state in which the first door  20  and the second door  40  seal the storage compartment  2 , a user may open the first door  20  while leaving the second door  40  as it is. 
     As shown in  FIG. 5A , in the state in which the first door  20  and the second door  40  are closed by a user, the pillar  100  is in the unfolded state, and is in contact with the first door  20  and the second door  40  so as to seal the storage compartment  2 .  FIG. 5A  shows the state in which the lifting guide unit  1400  is lowered and is caught by the pillar protrusion  130 . However, a concrete illustration and explanation thereof will be omitted. 
     As shown in  FIG. 5B , as the first door  20  is rotated, the distance between the first magnetic member  1212  and the first door magnetic member  26  is increased, and thus the rotary arm  1200  may be rotated in the clockwise direction. That is, as the repulsive force between the first magnetic member  1212  and the first door magnetic member  26  is reduced, the first door magnetic member  26  cannot sufficiently repel the first magnetic member  1212 , and thus the rotary arm  1200  may be rotated in the clockwise direction by the restoring force of the elastic member  1300 . The clockwise rotation of the rotary arm  1200  may be stopped at a position where the restoring force of the elastic member  1300  and the repulsive force between the first magnetic member  1212  and the first door magnetic member  26  are in equilibrium. 
     At this time, as the distance between the second door magnetic member  28  and the second pillar magnetic member  120  is decreased, magnetic interference may occur between the second door magnetic member  28  and the second pillar magnetic member  120  due to the repulsive force therebetween. Therefore, the pillar  100  may start to be rotated in the counterclockwise direction by the magnetic interference between the second door magnetic member  28  and the second pillar magnetic member  120 . 
     As shown in  FIG. 5C , when the first door  20  is rotated to a specific position, the first door magnetic member  26  and the first magnetic member  1212  are not substantially influenced by the repulsive force, and the elastic member  1300  may therefore be restored to the original shape thereof. 
     Because magnetic interference due to the repulsive force is not present between the second magnetic member  1222  and the first pillar magnetic member  110 , the pillar  100  may be sufficiently folded. Further, because the pillar-fixing unit  50  applies force in the direction in which the pillar  100  is folded, the pillar  100  may be more easily rotated in the counterclockwise direction so as to be folded. 
     When only the first door  20  is in the opened state, the pillar  100  is in the folded state. Therefore, when a user pulls the drawer located near the first door  20  outwards, the drawer does not interfere with the pillar  100 . Accordingly, even when the drawer located near the first door  20  and the drawer located near the second door  40  have the same width, withdrawal of the drawer by the user is not interrupted. That is, when the drawer is drawn outwards in the state in which only the door not having the pillar is opened, the pillar does not block the path along which the drawer moves outwards. 
     In addition, when only the first door  20  is rotated in the state in which the second door  40  is closed, the pillar  100  is changed to the folded state, and thus the length of the path along which the basket installed to the rear side of the first door  20  moves may be increased. This is because the pillar  100  is folded so as not to interfere with a structure installed on the first door  20 , thereby increasing the moving path of the structure. 
       FIGS. 6A to 6C  are views for explaining the state in which the second door is being opened when the first door is in the closed state. 
     Referring to  FIGS. 6A to 6C , the second door  40  may be rotated in the state in which the first door  20  is closed. 
     At this time, in order to allow the second door  40  to be rotated and opened, the rotation of the second door  40  should not be interrupted by interference between the pillar  100  and the first door  20 . 
     In this embodiment, the pillar  100  may be rotated by interference with the first door  20 . Therefore, when the second door  40  is rotated in the state in which the first door  20  remains stationary, the pillar  100  may collide with the first door  20  and may be folded thereby. 
     Therefore, a user may open the second door  40  without being impeded by the first door  20 . 
     In the state of  FIG. 6A , because the pillar protrusion  130  is caught by the lifting guide unit  1400 , while the second door  40  is rotated together with the pillar  100 , the pillar  100  may be folded by being rotated relative to the second door  40 . 
     Subsequently, in the states of  FIGS. 6B and 6C , because the pillar  100  moves away from the lifting guide unit  1400 , the lifting guide unit  1400  is changed to the raised state. A description related thereto will be made later with reference to  FIGS. 8 to 10C . 
       FIGS. 7A to 7C  are views for explaining the state in which the second door is being closed when the first door is in the closed state. 
     Referring to  FIGS. 7A to 7C , the second door  40  may be rotated in the state in which the first door  20  closes the storage compartment  2 . At this time, the pillar  100  is maintained in the folded state. As shown in  FIGS. 6A to 6C , when the second door  40  is opened, the pillar  100  is changed to the folded state. Furthermore, the pillar-fixing unit  50  applies force so that the pillar  100  remains folded. Therefore, the pillar  100  is in the folded state when the second door  40  is in the opened state. 
     Therefore, when the second door  40  is rotated so as to seal the storage compartment  2  in the state in which the first door  20  seals the storage compartment  2 , the second door  40  may be rotated without interference between the pillar  100  and the first door  20 . 
     That is, as shown in  FIG. 7B , while the second door  40  is rotated, the pillar  100  is in the folded state, and thus is not caught by the first door  20 . 
     As the second door  40  is rotated so as to seal the storage compartment  2 , magnetic interference occurs between the second magnetic member  1222  and the first pillar magnetic member  110 . At this time, a magnetic repulsive force is generated between the second magnetic member  1222  and the first pillar magnetic member  110 , and the pillar  100  may be rotated by the second magnetic member  1222  at a certain time. 
     Because the repulsive force generated between the first magnetic member  1212  and the first door magnetic member  26  substantially makes the rotary arm  1200  stationary, the rotary arm  1200  is not rotated, and thus the position of the second magnetic member  1222  is not changed. As the second door  40  is rotated, the position of the first pillar magnetic member  110  may be changed, and thus the pillar  100  may be rotated in the clockwise direction. 
     As shown in  FIG. 7C , when the second door  40  is rotated so as to seal the storage compartment  2 , the pillar  100  may be rotated so as to come into contact with the first door  20  and the second door  40  while overcoming the force of the pillar-fixing unit  50  due to the repulsive force generated between the second magnetic member  1222  and the first pillar magnetic member  110 . In the state of  FIG. 7C , unlike the states of  FIGS. 7A and 7B , the lifting guide unit  1400  may be lowered, and the pillar protrusion  130  may come into contact with the lifting guide unit  1400 . 
       FIG. 8  is a cross-sectional view illustrating the operation of the lifting guide unit. 
     Referring to  FIG. 8 , the lifting guide unit  1400  is provided with a steel plate member  1420 , which magnetically interferes with the first pillar magnetic member  110 . If a magnet approaches the steel plate member  1420 , the steel plate member  1420  may be moved toward the magnet by an attractive force. 
     The lifting guide unit  1400  includes a case  1410 , which envelops the steel plate member  1420 , and an elastic member  1430 , which elastically supports the case  1410  in the upward direction. One end of the elastic member  1430  is secured to the inside of the transmission unit  1000 , and the opposite end thereof is secured to the case  1410 , thereby guiding the vertical movement of the case  1410  relative to the transmission unit  1000 . The transmission unit  1000  has therein a space in which the case  1410  can move vertically. 
     The steel plate member  1420  may be disposed in the lower side of the case  1410  so as to be located close to the first pillar magnetic member  110 . 
     When the first pillar magnetic member  110  moves close to the transmission unit  1000 , i.e. the lifting guide unit  1400 , magnetic interference between the first pillar magnetic member  110  and the steel plate member  1420  may be increased, the elastic member  1430  may be extended, and thus the case  1410  may be lowered. Conversely, when the first pillar magnetic member  110  moves away from the transmission unit  1000 , i.e. the lifting guide unit  1400 , magnetic interference between the first pillar magnetic member  110  and the steel plate member  1420  may be decreased, the elastic member  1430  may be restored to the original size thereof, and thus the case  1410  may be raised. When the elastic member  1430  has been restored to the original size thereof, the case  1410  is completely embedded in the transmission unit  1000 . Thus, a user may not recognize the presence of the lifting guide unit  1400 . Further, a user may use the storage compartment  2  without being impeded by the lifting guide unit  1400 . 
       FIGS. 9A to 9C  are views for explaining the state in which the first door and the second door are both being opened at the same time, and  FIGS. 10A to 10C  are side views of  FIGS. 9A to 9C . In  FIGS. 9A to 10C , the lifting guide unit is mainly illustrated, and the remaining elements of the transmission unit are omitted. 
       FIG. 10A  is a side view illustrating the state of  FIG. 9A ,  FIG. 10B  is a side view illustrating the state of  FIG. 9B , and  FIG. 10C  is a side view illustrating the state of  FIG. 9C . 
     Referring to  FIGS. 9A and 10A , the first door  20  and the second door  40  close the storage compartment  2  so as to seal the storage compartment  2 . 
     The pillar  100  is in contact with the first door  20  and the second door  40 , and is in the unfolded state so as to seal the storage compartment  2 . 
     Accordingly, the lifting guide unit  1400  is located close to the first pillar magnetic member  110 , and thus the lifting guide unit  1400  is lowered. At this time, because the pillar protrusion  130  is disposed on the rear surface of the lifting guide unit  1400  (the right surface on the basis of  FIG. 10A ), the pillar protrusion  130  may guide the rotating direction of the lifting guide unit  1400 . 
     When a user rotates both the first door  20  and the second door  40  at the same time, the rotary arm  1200  may remain stationary without rotating. This is because, when the first door  20  and the second door  40  are rotated at the same time, variation in the magnetic force occurs on both the left side and the right side of the rotary arm  1200 , and thus the rotary arm  1200  may not be rotated, depending on the circumstances. 
     In this case, referring to  FIGS. 9B and 10B , the rear side of the lifting guide unit  1400  is in contact with the pillar protrusion  130 . When the second door  40  is rotated, the pillar  100 , i.e. the pillar protrusion  130 , is movable, whereas the lifting guide unit  1400  is in a stationary state. Thus, the pillar protrusion  130  cannot pass through the lifting guide unit  1400 , but is folded. That is, the pillar protrusion  130  is moved along the circumference of the lifting guide unit  1400 , and the pillar  100  is therefore rotated in the direction in which the pillar  100  is folded by the pillar protrusion  130  and the lifting guide unit  1400 . 
     Referring to  FIGS. 9C and 10C , the pillar  100  is also folded when the first door  20  and the second door  40  are rotated at the same time. 
     As shown in  FIG. 10C , when the second door  40  is sufficiently opened, the pillar  100  moves away from the transmission unit  1000 . Therefore, the intensity of the magnetic force that is exerted on the lifting guide unit  1400  by the pillar  100  is reduced, and thus the lifting guide unit  1400  is raised. Because the lifting guide unit  1400  is completely inserted into the transmission unit  1000 , a user may not recognize the presence of the lifting guide unit  1400 , and may use the storage compartment without being impeded by the lifting guide unit  1400 . 
     In general, when a user puts food into or takes the same out of the storage compartment, the storage compartment is in the state of being sufficiently opened by the door, and thus the lifting guide unit  1400  is in the state of being inserted into the transmission unit  1000 . Therefore, a user may conveniently use the storage compartment without being influenced by the lifting guide unit  1400 . 
     The present invention is not limited to the above-described exemplary embodiments, and, as is apparent from the appended claims, the present invention may be modified by those skilled in the art to which the present invention pertains, and such modification falls within the spirit and scope of the present invention.