Patent Publication Number: US-7581796-B2

Title: Refrigerator having basket lift apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a divisional of U.S. patent application Ser. No. 11/178,438 filed on Jul. 12, 2005, which claims priority to Korean Application No. 2004-0059927, filed Jul. 29, 2004, the contents of which are expressly incorporated by reference in their entireties. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a refrigerator having a basket lift apparatus, and particularly, to a refrigerator having a basket lift apparatus capable of improving convenience for a user by lifting a basket when the basket received in a lower portion of a body is taken out. 
   2. Description of the Background Art 
     FIG. 1  is a perspective view of a refrigerator in accordance with the conventional art, and  FIG. 2  is a sectional view of a refrigerator showing that a basket is received in a body. 
   The conventional refrigerator includes: a body  1  whose front is open and which has a receiving space; an upper cooling chamber  3  disposed at an upper side of the body  1 , having a pair of upper doors  2  opened in both directions, and storing food items; and a lower cooling chamber  6  disposed at a lower side of the body  1 , separated from the upper cooling chamber  3  by a partition wall  4 , and having a lower door  5  which is slidingly opened. 
   And, a machine room  8  having therein a compressor  7  and the like for generating cool air to be supplied to the upper cooling chamber  3  and the lower cooling chamber  6  is formed at the rear of the body  1 . 
   A basket  9  for receiving frozen food items is disposed at the lower cooling chamber  6  and can slide in the front and rear direction (back and forth). The lower door  5  is fixed at the front of the basket  9 . A user pulls the lower door  5  to open the basket  9  and pushes it to close the basket  9 . Here, a guide rail  10  is installed between the basket  9  and an inner surface of the lower cooling chamber  6  and guides the basket to allow the basket  9  to slide in the front and rear direction (back and forth). 
   And, a plurality of drawers  11  which are slidingly opened and store food items are provided above the basket  9 . 
   In the refrigerator in accordance with the conventional art having such a structure, when a user pulls the lower door  5  frontward in order to take out food items from the lower cooling chamber  6  or to put the food items therein, the basket  9  is slid and opened. And, when the lower door  5  is pushed rearward after the food items are taken out of the basket  9  or received therein, the basket  9  is slid and closed. 
   However, since the refrigerator in accordance with the conventional art having such a structure has a basket at its lower portion (i.e., the basket is installed at a lower side), a user has to stoop or crouch down to put in and/or take out food items into and/or from the basket, which causes inconvenience for the user. 
   SUMMARY OF THE INVENTION 
   Therefore, an object of the present invention is to provide a refrigerator having a basket lift apparatus capable of improving convenience for the user by lifting up a basket when the basket disposed at a lower portion of a body is opened. 
   To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a refrigerator comprising: a refrigerator body having cooling chambers; a frame slidingly received in a cooling chamber disposed at a lower portion of the body; a basket put on the frame and storing food items; a door positioned at the front of the frame and hingedly connected to the frame; a first link, one side of the first link being rotatably connected to the basket and the other side being slidably coupled with the frame; a second link disposed across the first link, one side of the second link being rotatably connected to the basket and the other side being slidably coupled with the frame; and a link drive unit connected to the first link or the second link and driving the link to allow the basket to ascend with respect to the frame. 
   To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a refrigerator comprising: a refrigerator body having cooling chambers; a frame slidingly received in a cooling chamber disposed at a lower portion of the body; a basket put on the frame and storing food items; a lower door positioned at the front of the frame and rotatably connected to the frame; a first link, one side of the first link being rotatably coupled with the frame and the other side being rotatably coupled with the basket; a second link disposed across the first link, one side of the second link being rotatably coupled with the basket and the other side being slidably coupled with the frame; a connection link, one side of the connection link being connected to the lower door and the other side being connected to the first link; and a fixing unit installed at the lower door and fixing the lower door to a specific position. 
   The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a unit of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. 
     In the drawings: 
       FIG. 1  is a perspective view of a refrigerator in accordance with the conventional art; 
       FIG. 2  is a sectional view of a lower portion of the refrigerator in accordance with the conventional art; 
       FIG. 3  is a perspective view of a refrigerator in accordance with a first embodiment of the present invention; 
       FIG. 4  is a sectional view showing a basket lift apparatus in accordance with the first embodiment of the present invention; 
       FIG. 5  is a cross sectional view of a link drive unit in accordance with the first embodiment of the present invention; 
       FIG. 6  is a sectional view taken along line VI-VI of  FIG. 5 ; 
       FIG. 7  is a view showing operation of the basket lift apparatus in accordance with the first embodiment of the present invention; 
       FIG. 8  is a cross sectional view showing a link drive unit in accordance with a second embodiment of the present invention; 
       FIG. 9  is a side view of a basket lift apparatus in accordance with a third embodiment of the present invention; 
       FIG. 10  is a cross sectional view showing a link drive unit in accordance with the third embodiment of the present invention; 
       FIG. 11  is a view showing operation of the basket lift apparatus in accordance with the third embodiment of the present invention; 
       FIG. 12  is a side view of a basket lift apparatus in accordance with a fourth embodiment of the present invention; 
       FIG. 13  is a cross sectional view of a link drive unit in accordance with the fourth embodiment of the present invention; and 
       FIG. 14  is a view showing operation of the basket lift apparatus in accordance with the fourth embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
   A plurality of embodiments of a refrigerator having a basket lift apparatus in accordance with the present invention may exist, and hereinafter, the most preferred embodiment will be described. 
     FIG. 3  is a perspective view of a refrigerator in accordance with a first embodiment of the present invention, and  FIG. 4  is a side view of a basket lift apparatus in accordance with the first embodiment of the present invention. 
   The refrigerator in accordance with the present invention includes: a refrigerator body  15  having cooling chambers; a frame  26  slidingly received in a cooling chamber disposed at a lower portion of the body  15 ; a basket  20  put on the frame  26  and storing food items; a lower door  22  positioned at the front of the frame  26  and integrally connected to the frame  26 ; a first link  28  whose one side is rotatably connected to the basket  20  and the other side is slidably coupled with the frame  26 ; a second link  30  disposed across the first link  28 , whose one side is rotatably connected to the basket  20  and the other side is slidably coupled with the frame  26 ; and a link drive unit (not shown) connected to the first link  28  or the second link  30  and driving the link to allow the basket  20  to ascend with respect to the frame  26 . 
   The body  15  includes: an upper cooling chamber  14  disposed at its upper portion and provided with a pair of upper doors  12  opened in both directions, and a lower cooling chamber  18  separated from the upper cooling chamber  14  by a partition wall  16  and disposed at a lower portion of the body  15 . 
   Preferably, the upper cooling chamber  14  is used as a refrigerating chamber for storing chilled food items, and the lower cooling chamber  18  is used as a freezing chamber for storing frozen food items. 
   A lower door  22  is disposed at the front of the lower cooling chamber  18  and is moved in a front and rear direction of the body  15  such that the basket  20  is taken out of or put into the lower cooling chamber  18 . And, a plurality of drawers  24  storing food items and put in or taken out in a front and rear direction are disposed at an upper side of the lower cooling chamber  18 . A machine room (not shown) that can receive a compressor and the like may be disposed at one side in the lower cooling chamber  18 . 
   The lower door  22  has a handle  21  at its front so that a user can hold and pull the lower door  22 . An operation switch  55  is installed at one side of the handle  21  and can be operated to allow the basket  20  to ascend when the basket is taken out. 
   The first link  28  is formed in a bar type having a certain length and is disposed inclined at a certain angle. One end of the first link  28  is slidably coupled with a first rail portion  32  formed at a lower end of the frame  26 , and its other end is hingedly connected to a shaft  33  formed at a lower end of the basket  20 . 
   Like the first link  28 , the second link  30  is formed in a bar type having a certain length. One end of the second link  30  is slidably coupled with the second rail portion  134  formed at a lower end of the frame  26  and its other end is hingedly connected to a shaft  35  formed at a lower end of the basket  20 . 
   The frame  26  is formed as a quadrangular box shape having a space where the basket  20  can be placed. 
   Two guide rails  40  along which the frame  26  slides in a front and rear direction are installed between a lower surface of the frame  26  and a bottom of the lower cooling chamber  18 . 
   Each guide rail  40  includes: a fixed rail  41  fixed on a bottom of the lower cooling chamber  18 ; a middle rail  42  slidably connected with the fixed rail  41 ; and a moving rail  43  slidably connected with the middle rail  42  and fixed on a bottom surface of the frame  26 . 
     FIG. 5  is a cross sectional view of a link drive unit in accordance with the first embodiment of the present invention, and  FIG. 6  is a sectional view taken along line VI-VI of  FIG. 5 . 
   As shown, the link drive unit  70  includes a pair of pulleys  73  disposed at both edges of the frame  26  along a direction in which the frame  26  moves, and separated from each other at a predetermined distance; a belt  75  movably coupled with a pair of pulley  73 ; and a driving motor  77  for moving the belt  75 . 
   A driving motor  77  for rotating the pulley  73  forward or backward is installed at a pulley  73  disposed at the rear, one of a pair of pulleys  73 . 
   A lower end of the first link  28  is integrally and movably coupled with a lower surface of the belt  75 . And a lower end of the second link  30  is integrally and movably coupled with an upper surface of the belt  75  such that the second link  30  can move in an opposite direction to a moving direction of the first link when the belt  75  runs. 
   In the present embodiment, the basket may be slid by a sprocket and a chain, instead of the pulley  73  and the belt  75 . 
   Also, in the present embodiment, lower ends of the first link  28  and the second link  30  are slidably coupled with the frame, and their upper ends are rotatably coupled with the basket. However, upper ends of the first link  28  and the second link  30  may be slidably coupled with the basket, and their lower ends may be rotatably coupled with the frame. 
   The operation and effects of the present invention will now be described. 
     FIG. 7  is a view showing the operation of the basket lift apparatus in accordance with the first embodiment of the present invention. 
   As shown, when putting and/or taking out food items into from the basket  20 , the user holds and pulls the handle  21  frontward. Then, the rail is extended, thereby allowing the frame  26  and the lower door  22  to be taken out frontward. 
   When intending to lift up the basket  20 , the user inputs a signal with the operation switch  55 . A control unit (not shown) having received the inputted signal controls the driving motor  77  to thereby rotate the driving motor  77  so that lower ends of the first link  28  and the second link  30  approach each other. When the pulley  73  begins to rotate integrally with the driving motor  77 , the belt  75  runs, allowing the lower ends of the first link  28  and the second link  30  to slide along the first rail portion  32  and the second rail portion  34 . When the lower ends of the first link  28  and the second link  30  move in a direction that the two approach each other, upper ends of the first link  28  and the second link  30  ascend vertically. Accordingly, the basket  20  ascends, being separated from the basket  20 . 
   Meanwhile, when the operation switch  55  is operated after the food items are completely received in and/or taken out of the basket  20 , the driving motor  77  rotates in a direction that the lower ends of the first link  28  and the second link  30  recede from each other. Thus, the basket  20  descends, getting near to the frame  26 . After the descending of the basket  20  is completed, the user holds and presses the handle  21  rearward, so that the guide rail  40  is shortened. Then, the frame  26  and the basket  20  are received in the lower cooling chamber  18 , and the lower door  22  blocks a front aperture of the lower cooling chamber  18 . 
     FIG. 8  is a cross sectional view showing a link drive unit in accordance with a second embodiment of the present invention. The same reference numerals designate the same part as those of the first embodiment, and the detailed descriptions thereon will be omitted. 
   As shown, the link drive unit  70  can move along a direction that the frame  26  moves and include a solenoid  78  provided with a rod  79  whose one side is integrally connected with the belt  75 . Namely, the rod  79  is moved forward or backward as an electric signal is supplied to the solenoid  78 , thereby driving the belt  75 . The solenoid  78  is used for the driving motor. 
     FIG. 9  is a side view of a basket lift apparatus in accordance with a third embodiment of the present invention, and  FIG. 10  is a cross sectional view of a link drive unit in accordance with the third embodiment of the present invention. The same reference numerals designate the same part as those of the first embodiment, and the detailed descriptions thereon will be omitted. 
   As shown, one side of a first link  128  is rotatably coupled with the frame  26 , and the other side is slidably coupled with the basket  20 . 
   A second link  130  is disposed across the first link  128 . One side of the second link  130  is slidably coupled with the frame  26 , and its other side is rotatably coupled with the basket  20 . 
   One side of the first link  128  is rotatably coupled with one side of the frame  26 , and a fourth rail portion  134  is formed at the other side of the frame  26  so that one side of the second link  130  can slide therealong in a direction that the frame  26  moves. 
   A third rail portion  132  along which the other side of the first link  128  slides is formed at one side of the basket  20 , and the other side of the second link  130  is rotatably coupled with the other side of the basket  20  by a shaft  66 . 
   The shaft  66  is provided with a link spring  67  for applying an elastic force in a direction that the second link  130  rotates to lift up the basket  20 . 
   The link spring  67  provides an elastic force which makes the first link  128  stand. When the basket  20  ascends, the link spring  67  provides an elastic force thereto, thereby facilitating the ascent of the basket  20 . Preferably, the link spring  67  is a spiral spring or a torsion spring. 
   The link drive unit  80  includes: a gear motor  85  integrally and rotatably coupled with a shaft  62  formed at a lower end of the first link  128 ; a gear  83  engaged with the gear motor  85 ; and a driving motor  87  integrally coupled with the gear  83  and rotating the gear  83 . 
   Although an upper end of the first link  128  and a lower end of the second link  130  slide and a lower end of the first link  128  and an upper end of the second link  130  rotatably coupled with the frame  26  and the basket  20 , respectively, in the present embodiment, the opposite construction may be employed. 
   Also, the shaft  62  formed at the lower end of the first link  128  is rotated by using the driving motor  87  in the present embodiment. However, an upper end of the second link  130  may be rotated, or an upper end of the first link  128  and/or a lower end of the second link may be slid by using a driving motor, a solenoid or the like. 
   The operation of the third embodiment of the present invention having such a structure will now be described. 
     FIG. 11  is a view showing operation of the basket lift apparatus in accordance with the third embodiment of the present invention. 
   As shown, when intending to move the basket  20  upwards in a state that the basket  20  has been taken out, a user operates an operation switch  55  disposed outside the lower door  22 . The link driving motor  87  rotates to rotate the first link upwardly, and thus the basket  20  moves upwardly with respect to the frame  26 . In order to lift up the basket  20 , the lower end of the second link  130  moves along a fourth rail portion  134 . At this time, the link spring  67  applies an elastic force to the second link  130 , thereby facilitating the ascent of the basket  20 . 
   Meanwhile, when the operation switch  55  is operated so as to move the basket  20  downward, the link driving motor  87  rotates to rotate the first link  128  downwardly. Accordingly, the upper end of the first link  128  and the lower end of the second link  130  slide to the rear areas of the basket  20  and the frame  26 , respectively, and the basket  20  descends to come in contact with and be supported by the frame  26 . 
     FIG. 12  is a side view of a basket lift apparatus in accordance with a fourth embodiment of the present invention, and  FIG. 13  is a cross sectional view of a link drive unit in accordance with the fourth embodiment of the present invention. The same reference numerals designate the same part as those of the first embodiment, and the detailed descriptions thereon will be omitted. 
   A refrigerator in accordance with the present invention includes: a refrigerator body  15  having cooling chambers; a frame  226  slidingly received in a cooling chamber disposed at a lower portion of the body  15 ; a basket  20  put on the frame  226  and storing food items; a lower door  22  positioned at the front of the frame  226  and rotatably connected with the frame  226 ; a first link  228  whose one side is rotatably coupled with the frame  226  and the other side is rotatably coupled with the basket  20 ; a second link  230  disposed across the first link  228 , whose one side is rotatably coupled with the basket  20  and the other side is slidably coupled with the frame  226 ; a connection link  300  whose one side is connected with the lower door  22  and the other side is connected to the first link  228 ; and a fixing unit  400  installed at the lower door  22  and fixing the lower door  22  at a specific position. 
   A hinge portion  143  is formed at a lower portion of the lower door  22  and is rotatably supported thereby. 
   A lower end of the first link  228  is rotatably connected to a front area of the frame, and a link spring  68  is connected to a shaft  62  formed at a lower end of the first link  228  so that the link  228  can rotate, moving the basket  20  upwards. Also, a rail portion  234  along which a lower end of the second link  230  slides in a front and rear direction is formed at a rear area of the frame  226 . 
   One end of the connection link  300  is rotatably connected to the lower door  22 , and its other end is rotatably connected to a specific place. 
   The fixing unit  400  includes: a first door fixing unit  410  formed at a rear surface of the lower door  22  and allowing the lower door  22  to remain in a downwardly-rotated (i.e., opened) state as the basket  20  ascends; and a second door fixing unit  420  allowing the lower door  22  to remain perpendicular to the frame  226  as the basket  20  descends. 
   The first door fixing unit  410  includes: a rod  411  having a certain length and rotatably connected to a rear surface of the lower door  22  by a shaft  414 ; a stopping hole  415  formed at the frame  226  such that the rod  411  passes therethrough; and a catching protrusion  412  formed at an end of the rod  411  and getting caught in the stopping hole  415 . Here, the rod  411  preferably has an inclined portion  413  so that the rod  411  can easily pass through the stopping hole  415  when the lower door  22  rotates. 
   Such a first door fixing unit  410  can allow the lower door  22  to maintain a current state since the rod  411  passes through the stopping hole  415  as the lower door  22  rotates and the catching protrusion  412  formed at an end portion of the rod  411  gets caught in the stopping hole  415  when the lower door  22  rotates as much as possible. 
   The second door fixing unit  420  includes: a locking hook  423  linearly movably mounted to the lower door  22 ; a locking hole  424  formed at an upper end of the front of the frame  226 , in which the locking hook  423  is locked; and a spring  427  providing an elastic force to the locking hook  423  in a direction that the locking hook  423  is locked in the locking hole  424 . 
   The locking hook  423  includes: an operation portion  428  disposed at a handle  21  of the lower door  22  and operated by a user; a rod portion  429  integrally connected with the operation portion  428  and linearly movably disposed inside the lower door  22 ; and a locking portion  431  formed at an end portion of the rod portion  429 , passing through a through hole  430  formed at a rear surface of the lower door  22  to be exposed outside the rear of the lower door  22 , and locked in the locking hole  424 . A guide inclined surface  422  is formed at one side of the locking portion  431  for the purpose of smooth contact with the locking hole  424 . 
   Two locking hooks  423  are formed as a pair and disposed at right and left sides of the lower door  22 , respectively. And a spring  427  is disposed between said pair of operation portions  428 . 
   When the user presses an operation portion  428 , the rod portion  429  is linearly moved and the locking portion  431  is separated from the locking hole  424 , so that the locking of the lower door  22  by the second door fixing unit  420  is released. 
   Although the basket  20  is lifted up by a pulling force of the lower door  22  and an elastic force of the link spring  68  in the present embodiment, the basket  20  may be lifted up only by the pulling force of the lower door  22  or by a rotation force of a driving motor. Also, the basket  20  may be lifted up by a rotation force of the driving motor and the elastic force of the link spring  68  that work at the same time. 
   The operation of the basket lift apparatus in accordance with the fourth embodiment of the present invention having such a structure will now be described. 
     FIG. 14  is a view showing operation of the basket lift apparatus in accordance with the fourth embodiment of the present invention. 
   When a user holds and pulls a handle  21  of the lower door  22 , the frame  226  is slid along the guide rail  40  to thereby be taken out from the lower cooling chamber  18 . At this time, the basket  20  put on the frame  226  is exposed to the outside. 
   In such a state, if the user operates the second door fixing unit  420 , the locking between the lower door  22  and the frame  226  is released. Namely, when the user presses the operation portion  428  of the locking hook  423 , the locking portion  431  comes out of the locking hole  424  formed at the frame  226 . Accordingly, the locking of the lower door  22  is released. 
   And, when the lower door  22  is rotated toward the front, a four-linkage mechanism which is hingedly connected between the lower door  22 , the frame  226  and the basket  20  is operated to lift up the basket  20 . Namely, when the lower door  22  is rotated, the first link connected to the lower door  22  by the connection link  300  is rotated together with the lower door  22 , and the second link  230  hingedly connected between the basket  20  and the frame  226  is placed upright by the rotation of the first link  228 , thereby lifting up the basket  20 . 
   At this time, the basket  20  is more easily lifted up by an elastic force of the link spring  68  mounted to the first link  228 , which makes the operation of a user easy. And, when the basket  20  is lifted up as much as possible, the first door fixing unit  410  mounted between the lower door  22  and the basket  20  is operated, thereby preventing the lower door  22  from returning back to an original position and thus allowing the basket  20  to remain lifted. 
   In contrast, when intending to move the basket  20  down, the user releases the locking of the first door fixing unit  410  and then presses the basket  22  downwards. Then, the basket  20  is put on the frame  26 . 
   Effects of the refrigerator having a basket lift apparatus in accordance with the present invention constructed and operated as above will now be described. 
   The user&#39;s convenience can be improved as the basket is lifted up by rotation of the lower door after the basket is taken out of the lower cooling chamber. 
   Also, since the basket is automatically lifted up when the user presses a switch after taking the basket outside, the user can more conveniently use the refrigerator. 
   As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims.