Abstract:
The present disclosure relates to a refrigerator having an air pressure adjusting apparatus for a storage container, and more particularly, a refrigerator having an air pressure adjusting apparatus for a storage container, capable of uniformly maintaining internal air pressure of the storage container by increasing the internal air pressure by way of an introduction of external air when the internal air pressure is excessively lowered and also preventing damages of the storage container. The refrigerator includes a storage container having an inner accommodating space and installed to be drawn out of and inserted into the refrigerator, and an air pressure adjusting apparatus to allow external air to be introduced into the storage container based on internal air pressure of the storage container, so as to increase the internal air pressure.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2012-0068738, filed on Jun. 26, 2012, the contents of which is incorporated by reference herein in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This specification relates to a refrigerator having an air pressure adjusting apparatus for a refrigerator storage container. 
         [0004]    2. Background of the Invention 
         [0005]    In general, a refrigerator is equipment for keeping foods and the like in a cold state for an extended time by generating cold air in response to driving a refrigerating cycle installed inside the refrigerator and supplying the generated cold air into a refrigerating chamber and a freezing chamber. 
         [0006]    The refrigerator is typically provided with a storage container for keeping and storing vegetables. Also, when vegetables are generally stored in the refrigerator, they should be kept in the freshest state. Therefore, it may be important to maintain the space for keeping vegetables in an optimal condition. 
         [0007]      FIG. 1  is a perspective view illustrating a storage container for a refrigerator according to the related art. A storage container  10  for a refrigerator according to the related art may include a box receiving unit  11  and a box  13 . 
         [0008]    The storage container for the refrigerator, as illustrated in  FIG. 1 , is a drawer-type storage container  10 , which has a two-box form having the box receiving unit  11  and the box  13 . Or, although not shown, the storage container  10  for the refrigerator may be implemented as a singe-box form (1-box form) that a cover on a box closes the box. 
         [0009]    For the two-box type storage container as shown in  FIG. 1 , when the box  13  is closed by being inserted into the box receiving unit  11 , an inside of the storage container  10  is sealed and maintained almost in a vacuum state, resulting in improvement of freshness of vegetables stored. 
         [0010]    This related art two-box type storage container is sealed in the form of the drawer to keep foods fresh for an extended time. Here, a vacuum pump is mounted in the sealed storage container and the storage container is set to be under predetermined pressure by the vacuum pump, such that the inside of the storage container can be uniformly maintained in a state close to vacuum (approximately 0.8 atm for example). Accordingly, foods and the like may be kept fresh in the storage container for the extended time. 
         [0011]    However, the related art storage container for vacuum storage has a difficulty in uniformly maintaining an internal vacuum degree (a degree close to vacuum) and sometimes causes an excessive vacuum degree. These may greatly affect the freshness of vegetables and the like stored in the storage container. 
         [0012]    In addition, when the vacuum pump is controlled to maintain a predetermined vacuum degree in the storage container, the vacuum pump may be continuously operating due to several reasons such as system breakdown, a system error and the like. This may cause the internal air pressure of the storage container to be kept lowered. Accordingly, the internal air pressure of the storage container may be in an excessively lowered state. 
       SUMMARY OF THE INVENTION 
       [0013]    Therefore, to overcome the drawbacks of the related art, an aspect of the detailed description is to provide a refrigerator having an air pressure adjusting apparatus for a refrigerator storage container, capable of uniformly maintaining internal air pressure of the storage container by opening a path for allowing external air to be introduced into the storage container when the internal air pressure of the storage container is excessively lowered below a predetermined air pressure. 
         [0014]    Another aspect of the detailed description is to provide a refrigerator having an air pressure adjusting apparatus for a refrigerator storage container, capable of maintaining an appropriate vacuum degree by raising air pressure using external atmospheric pressure so as to prevent internal air pressure of the storage container from being drastically lowered. 
         [0015]    Another aspect of the detailed description is to provide a refrigerator having an air pressure adjusting apparatus for a refrigerator storage container, capable of preventing an abnormal decrease of internal air pressure of the storage container by mounting the air pressure adjusting apparatus onto an outer wall of the storage container to be exposed to external air, and preventing in advance the risk of breakage of the storage container even when internal air pressure is continuously lowered due to breakdown of a vacuum pump, an error and the like. 
         [0016]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, there is provided a refrigerator including a storage container having an inner accommodating space and installed to be drawn out of and inserted into the refrigerator, and an air pressure adjusting apparatus to allow external air to be introduced into the storage container based on internal air pressure of the storage container, so as to increase the internal air pressure. 
         [0017]    The air pressure adjusting apparatus may selectively allow the external air to be introduced into the storage container based on a difference between the internal air pressure of the storage container and external air pressure. 
         [0018]    The refrigerator may further include a vacuum pump to suck internal air of the storage container. Here, the air pressure adjusting apparatus may allow the external air to be introduced into the storage container when the internal air pressure of the storage container is lowered below a predetermined air pressure by the vacuum pump. 
         [0019]    The air pressure adjusting apparatus may further include a casing having a through hole formed through the casing to allow for an introduction of external air therethrough, and a movable member installed in the casing to be movable up and down so as to selectively close and open the through hole based on a difference between the internal air pressure of the storage container and the external atmospheric pressure. 
         [0020]    Here, the casing may be formed in a shape of a hollow tube, and have an upper portion with the through hole formed therethrough, and a lower portion open and inserted into the storage container. 
         [0021]    The movable member may be formed of rubber. 
         [0022]    In accordance with another exemplary embodiment of the present disclosure, the air pressure adjusting apparatus may further include a supporting member fixedly installed within the casing with being spaced apart from the movable member, and an elastic member fixedly installed between the movable member and the supporting member. 
         [0023]    Here, the casing may include a cylindrical part formed in a shape of a hollow circular pipe, and the cylindrical part may include, on an inner circumferential surface thereof, a first contact portion onto which the movable member is adhered, and a second contact portion onto which the supporting member is adhered. 
         [0024]    The movable member may include an opening/closing portion to open and close the through hole, a deformable portion connected to the opening/closing portion and allowing for up and down movements of the opening/closing portion, and an elastic member fixing portion to fix the elastic member. 
         [0025]    Here, the deformable portion may include a plurality of air holes formed through the deformable portion in a thickness direction of the deformable portion. Also, the deformable portion may be formed as a circular rubber member adhered onto an inner circumferential surface of the cylindrical casing, and be concavely deformed and restored in the thickness direction thereof in response to the down and up movements of the opening/closing portion formed on a central portion of the casing, with an outer circumference of the deformable portion being fixedly adhered onto the casing. 
         [0026]    The elastic member may be implemented as a spring. 
         [0027]    The supporting member may include an elastic member fixing portion to fix the elastic member, and a plurality of air holes formed through the supporting member in a thickness direction of the supporting member. 
         [0028]    In accordance with another exemplary embodiment of the present disclosure, the supporting member may include an elastic member fixing portion formed on an upper surface of the supporting member to fix the elastic member, a plurality of air holes formed through the supporting member in a thickness direction of the supporting member, a frame fixedly adhered onto a second contact portion of the casing, and a plurality of supporting legs extending from the frame toward a central portion of the supporting member. Accordingly, the supporting member may fixedly support the elastic member fixing portion on an inner circumferential surface of the casing. 
         [0029]    The storage container may include a box having a front part and a main body, and forming an inner accommodating space, the box being drawn out and inserted, and a box receiving unit to receive the box therein in an airtight state. 
         [0030]    As described above, the present disclosure may acquire the following effects by the aforementioned technical solutions and configurations, coupling relationships and operation relationships to be explained later. 
         [0031]    The present disclosure may allow internal air pressure of a storage container to be uniformly maintained by opening an path for an introduction of external air into the storage container even when the internal air pressure is lowered below a predetermined air pressure. 
         [0032]    The present disclosure may prevent damage of the storage container due to a continuously decrease of the internal air pressure of the storage container, which may be caused by breakdown of a system, a breakdown of a vacuum pump, an error and the like. 
         [0033]    Also, the present disclosure may prevent the internal air pressure of the storage container from being lowered below a predetermined air pressure by adjusting an elastic coefficient of an elastic member of the air pressure adjusting apparatus, namely, a spring constant of a spring. 
         [0034]    Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0035]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments and together with the description serve to explain the principles of the invention. 
           [0036]    In the drawings: 
           [0037]      FIG. 1  is a perspective view of a storage container for a refrigerator according to the related art; 
           [0038]      FIG. 2  is a perspective view illustrating a storage container having an air pressure adjusting apparatus in accordance with one exemplary embodiment; 
           [0039]      FIG. 3  is an inner perspective view of the air pressure adjusting apparatus in accordance with the one exemplary embodiment; 
           [0040]      FIG. 4  is an inner sectional view illustrating an operating state of the air pressure adjusting apparatus in accordance with the one exemplary embodiment; 
           [0041]      FIG. 5  is a perspective view illustrating a movable member of the air pressure adjusting apparatus in accordance with the one exemplary embodiment; and 
           [0042]      FIG. 6  is a perspective view illustrating a supporting member of the air pressure adjusting apparatus in accordance with the one exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0043]    Description will now be given in detail of a refrigerator having an atmospheric pressure controllable storage container and a storage method thereof according to the exemplary embodiments, with reference to the accompanying drawings. 
         [0044]    Terms or words used in this specification and the claims should not be construed as being limited to typical or dictionary definition, but be understood as meaning and conception that come within the technical scope of the present disclosure based on a principle that the inventor is able to appropriately define the conception of terms for describing his invention in the best way. 
         [0045]    Therefore, the preferred embodiments described herein and configurations shown in the drawings are merely illustrative and should not be construed to limit the spirit of the invention. Therefore, it should be understood that there can be various equivalents and variations which can substitute the preferred embodiments at the time point of filing this application. 
         [0046]    Hereinafter, description will be given of an air pressure adjusting apparatus for a storage container and a refrigerator having the same in accordance with one exemplary embodiment, with reference to  FIGS. 2 to 6 . 
         [0047]      FIG. 2  is a perspective view illustrating a storage container for a refrigerator in accordance with one exemplary embodiment,  FIG. 3  is an inner perspective view of the air pressure adjusting apparatus in accordance with the one exemplary embodiment, and  FIG. 4  is an inner sectional view illustrating an operating state of the air pressure adjusting apparatus in accordance with the one exemplary embodiment. 
         [0048]    Also,  FIG. 5  is a perspective view illustrating a movable member of the air pressure adjusting apparatus, and  FIG. 6  is a perspective view illustrating a supporting member of the air pressure adjusting apparatus. 
         [0049]    Referring to  FIGS. 2 and 3 , a refrigerator according to the present disclosure may include a storage container  1  having a box  213  formed by a front portion and a main body, forming an inner storage space as an accommodation space, and installed to be drawn out of and inserted into the refrigerator, and a box receiving unit  211  for receiving the box  213  therein and hermetically closing an inside of the box  213 , and an air pressure adjusting apparatus  100  installed on the storage container  1  to raise internal air pressure of the storage container  1  by allowing an introduction of external air into the storage container  1  based on a level of the internal air pressure. 
         [0050]    The storage container  1  is a container inserted in a general refrigerator and may be implemented as a single-box (or 1-box) type or a two-box (or 2-box) type. The single-box (1-box) type may include a box having an upper opening and a cover to cover the upper opening. The two-box type may be a type of storage container which is sealed in a drawer-like manner, as illustrated in  FIG. 2 , and include a box receiving unit  211  having a front opening and a box  213  inserted in and drawn out of the box receiving unit  211 . This exemplary embodiment illustrates a two-box type storage container  1 , but not be limited to this. The storage container according to the present disclosure may also be implemented as a single-box type. 
         [0051]    The air pressure adjusting apparatus  100 , as illustrated in  FIG. 2 , may preferably be inserted into the storage container  1  from the outside of the box receiving unit  211 . 
         [0052]    Especially, the air pressure adjusting apparatus  100  may be installed on an upper plate  211   a  or a side plate  211   b  of the box receiving unit  211 . Here, when it is installed on the side plate  211   b , the apparatus may overlap the box  213  when the box  213  is inserted. In this case, the apparatus may be inserted into the upper plate  211   a . Although not shown, the air pressure adjusting apparatus  100  may also be installed on a rear surface of the box receiving unit  211 . 
         [0053]    In the air pressure adjusting apparatus  100 , when the internal air pressure of the storage container  1  is lowered below a predetermined air pressure, a path for an introduction of external air into the storage container  1  (a through hole  103  in  FIG. 3 ) may be open to raise the internal air pressure, thereby maintaining uniform internal air pressure of the storage container  1 . 
         [0054]    The air pressure adjusting apparatus  100  may operate as a valve which is driven when the internal air pressure of the storage container  1  is below the predetermined air pressure after the box  213  is hermetically received in the box receiving unit  211 . 
         [0055]    When the internal pressure of the storage container is lowered below the predetermined air pressure, the air pressure adjusting apparatus  100  functioning as the valve may be opened to allow external air to be introduced into the storage container  1 , thereby preventing the internal air pressure of the storage container  1  from being lowered below the predetermined air pressure. This may result in adjusting the internal air pressure, and accordingly avoiding in advance spoiling, drying and the like of stuffs stored in the storage container. 
         [0056]    Referring to  FIG. 3 , the air pressure adjusting apparatus  100  may include a casing having a through hole  103  formed through the casing to allow for an introduction of external air, a movable member  110  installed in the casing and movable forward and away from the through hole, for example, upwardly and downwardly, to selectively open and close the through hole  103  based on a level difference between internal air pressure of the storage container  10  and external air pressure, a supporting member  150  fixed in the casing with being spaced apart from a lower portion of the movable member  110 , and an elastic member  130  fixed between the movable member  110  and the supporting member  150 . 
         [0057]    The air pressure adjusting apparatus  100  may function as a valve which is driven under a predetermined air pressure. Specifically, the air pressure adjusting apparatus  100  may be open below a predetermined air pressure and closed over a predetermined air pressure. Here, the predetermined air pressure may be decided by adjusting an elastic coefficient of the elastic member  130 . 
         [0058]    The casing may have a form of a hollow tube. The casing may include a upper surface through which the through hole  103  is formed, and an open lower surface hermetically inserted into the storage container  1 . The casing may also be formed in a cylindrical shape or a square shape. 
         [0059]    Still referring to  FIG. 3 , an inside of the casing may be divided into a first inner space A, a second inner space B and a third inner space C based on the movable member  110  and the supporting member  150 . Here, an outer circumference of the movable member  110  may adhered onto a first contact portion  105   a  of an inner circumferential surface of the casing. The first inner space A and the second inner space B may change due to curvature of the movable member  110 . 
         [0060]      FIG. 4  illustrates a boundary between the first inner space A and the second inner space B. When the storage container  1  is under an appropriate internal air pressure (see  FIG. 4A ), the movable member  110  may not be downwardly curved (or concavely transformed) and accordingly an even boundary may be present between the first and second inner spaces A and B. However, when the internal air pressure of the storage container  1  is lower than external air pressure (see  FIG. 4B ), the movable member  110  may be downwardly curved and a downwardly curved boundary may be present between the first and second inner spaces A and B. 
         [0061]    The casing may include a cylindrical part  105  formed in a hollow circular tube. On an inner circumferential surface of the cylindrical part  105  may be provided with a first contact portion  105   a  onto which the movable member  110  is adhered, and a second contact portion  105   b  onto which the supporting member  150  is adhered. 
         [0062]    Referring to  FIGS. 3 and 5 , the movable member  110  may include an opening/closing portion  111  to open and close the through hole  103 , a deformable portion  113  to allow for up and down movements of the opening/closing portion  111 , and an elastic member fixing portion  115  to fix the elastic member  130 . 
         [0063]    The opening/closing portion  111 , as shown in  FIGS. 3 to 5 , may open and close the through hole  103 , as an air intake opening through which external air is introduced after the casing is hermetically coupled to the storage container  1 . The through hole  103  may be open and closed in response to down and up movements of the opening/closing portion  111 . Therefore, the opening/closing portion  111  may preferably be formed of rubber to airtightly close the through hole  103 . 
         [0064]    The deformable portion  113  of the movable member  111  may be implemented as a circular rubber member which is adhered onto the inner circumferential surface of the cylindrical casing. The deformable portion  113  may be moved up and down in response to the up and down movements of the opening/closing portion  111 , which is formed on a central area of he deformable portion  113 , in a state that the outer circumference of the deformable portion  113  is fixed onto the casing. 
         [0065]    As illustrated in  FIGS. 4 and 5 , the up and down movements of the opening/closing portion  111  may be realized by the deformable portion  113 . The deformable portion  113  may be formed of rubber to be concavely transformed (downwardly curved) and then restored to its initial shape, with the outer circumference of the deformable portion  113  being fixedly adhered onto the first contact portion  105   a  of the casing. 
         [0066]    The deformable portion  113  may have a planar form as the same shape (for example, a circular shape) as a section of the casing, and be made of rubber with a predetermined elastic coefficient for transformation. Here, the predetermined elastic coefficient of the deformable portion  113  may depend on air pressure, which is desired to be maintained within the storage container. 
         [0067]    Referring to  FIGS. 3 and 4 , the deformable portion  113  may include a plurality of air holes  113   a  formed through the deformable portion  113  in a thickness direction of the deformable portion  113 . The movable member  110  may be made of rubber. 
         [0068]    Referring to  FIGS. 4 and 5B , the elastic member  130  may be fixed to the elastic member fixing portion  115  which is located on a central area of a lower surface of the movable member  110 . The elastic member  130  may have a lower end supported by the supporting member  150  to prevent up and down movements thereof, and an upper end pressed and extended as the movable member  110  moves down and up with being concavely transformed (or downwardly curved) and restored. The elastic member  130  may be a spring having a predetermined elastic coefficient. 
         [0069]    An air pressure maintenance condition, which is preset according to a difference between the internal air pressure of the storage container  1  and external pressure, may be decided based on the elastic coefficient of the deformable portion  113  and the elastic coefficient of the elastic member  130 . Especially, referring to  FIGS. 3 and 4 , when the elastic member  130  is the spring, the internal air pressure of the storage container  1  to be maintained may be set by an elastic restoring force F k  using a spring constant. 
         [0070]    Referring to  FIG. 4 , when the deformable portion  113  is maintained in an even state (see  FIG. 4A ), the internal air pressure of the storage container  1  may be higher than a predetermined air pressure. Accordingly, an upper surface  111   a  of the opening/closing portion  111  may close the through hole  103  to maintain an airtight state of the inside of the storage container  1  and the internal air pressure of the storage container may thusly be maintained as it is (see  FIG. 4A ). 
         [0071]    However, when the internal air pressure of the storage container  1  becomes lower than the predetermined air pressure (for example, 0.8 atm) to generate an air pressure difference (i.e., a pressure difference between inside and outside of the storage container  1 ) which has a greater force than an elastic restoring force, which is generated by the elastic coefficients of the movable member  110  and the elastic member  130 , the opening/closing portion  111  may be pushed down and the deformable portion  113  may be sunk to be elastically transformed (see  FIG. 4B ). 
         [0072]    Referring to  FIG. 4B , when external air is introduced into the storage container  1  due to the generated air pressure difference, the external air may be introduced into the storage container  1  through the air holes  113   a  of the deformable portion  113 . When the internal air pressure of the storage container  1  increases appropriately in response to the introduction of the external air, the opening/closing portion  111  may be moved by the elastic restoring force of the movable member  110  and the elastic member  130  to airtightly close the through hole  103  again. 
         [0073]    As such, when the internal air pressure of the storage container  1  is lowered below the predetermined air pressure, the external air may be introduced by the air pressure adjusting apparatus in accordance with the one exemplary embodiment, so as to maintain a predetermined air pressure based on the elastic coefficients. 
         [0074]    For example, when desiring to maintain internal air pressure of the storage container at about 0.8 atm, the movable member  110  and the elastic member  130  may be designed to have elastic restoring forces due to an air pressure difference between atmospheric pressure (1 atm) and the air pressure of 0.8 atm by way of appropriately combining the elastic coefficient of the movable member  110  and the elastic coefficient of the elastic member  130 . 
         [0075]    Since the elastic member  130  is implemented as a spring, an elastic restoring force F k  may be computed by calculating a spring constant (F k =k (spring constant)*x(spaced distance)). 
         [0076]    Referring to  FIGS. 3 and 4 , the supporting member  150  may include an elastic member fixing portion  151  to fix the elastic member  130 , and a plurality of air holes  153  formed through the supporting member  150  in a thickness direction of the supporting member  150 . 
         [0077]    The supporting member  150  may be made of plastic or the like with rigidity, which is as strong as being unable to be moved up and down. The supporting member  150  may be fixed onto the second contact portion  105   b  of the inner circumferential surface of the casing. 
         [0078]    The third inner space C below the supporting member  150  may be connected to the inner space of the storage container  1 . When the opening/closing portion  111  opens the through hole  103 , external air may pass through the first inner space A to be introduced into the inner space of the storage container  1  through the air holes  113   a  of the movable member  110  and the air holes  153  of the supporting member  150 . 
         [0079]    In accordance with another exemplary embodiment illustrated in  FIG. 6 , the supporting member  150  may include a frame  151   a  fixedly adhered onto the second contact portion  105   b  of the casing, and a plurality of support beams  151   b  extending from the frame  151   a  to a central portion of the supporting member  150 . With the structure, the supporting member  150  may fixedly support the elastic member fixing portion  151  on the inner circumferential surface of the casing. 
         [0080]    In the state that each supporting leg  151   b  extends and is connected to the elastic member fixing portion  151 , a space between the adjacent supporting legs  151   b  may form the air hole  153 . 
         [0081]    When the air holes  153  are great in size, the external air introduced into the second inner space B may smoothly flow into the storage container  1  as the third inner space C. Therefore, the supporting member  150  may be implemented by the frame  151   a  and the supporting legs  151   b.    
         [0082]    Consequently, in order to prevent the internal air pressure of the storage container  1  from being excessively lowered rather than external atmospheric pressure, the internal air pressure of the storage container  1  may be appropriately raised by using the external atmospheric pressure, and maintained in a desired air pressure state. 
         [0083]    The air pressure adjusting apparatus  100  may be installed on an outer wall of the storage container  1  to be exposed to external air, thereby preventing the internal air pressure of the storage container  1  from being abnormally lowered. Also, when the air pressure is continuously lowered due to breakdown of a vacuum pump, an error and the like, the risk of breakage of the storage container  1  may be prevented in advance. 
         [0084]    In addition, the elastic coefficient of the elastic member  130  of the air pressure adjusting apparatus  100 , namely, a spring constant of the spring may be adjusted to prevent the internal air pressure of the storage container  1  from being lowered below a predetermined air pressure. 
         [0085]    In accordance with another exemplary embodiment of the present disclosure, an air pressure adjusting apparatus  100  may include a casing formed in a shape of a hollow tube, and having an upper surface with a through hole  103  formed through the upper surface to allow for an introduction of external air and an open lower surface, a movable member  110  installed in the casing and movable up and down, to selectively close and open the through hole  103  based on a difference between internal air pressure in a weak vacuum state and external atmospheric pressure, a supporting member  150  fixedly installed in the casing with being spaced apart from a lower portion of the movable member  110 , and an elastic member  130  fixedly installed between the movable member  110  and the supporting member  150 . 
         [0086]    The movable member  110  may include an opening/closing portion  111  to open and close the through hole  103 , a deformable portion  113  having a plurality of air holes  113   a  formed through the movable member  110  in a thickness direction of the movable member  110 , and allowing for up an down movements of the opening/closing portion  111 , and an elastic member fixing portion  115  to fix the elastic member  130 . The deformable portion  113  may be made of rubber to allow for the up and down movements of the opening/closing portion  111 . 
         [0087]    The elastic member  130  may be implemented as a spring. The supporting member  150  may include an elastic member fixing portion  151  to fix the spring, and a plurality of air holes  153  formed through the elastic member  130  in a thickness direction of the elastic member  130 . 
         [0088]    The air pressure adjusting apparatus  100  in accordance with the another exemplary embodiment may be an apparatus functioning as a valve, which operates when internal air pressure of the storage container  1  is below a predetermined air pressure. The air pressure adjusting apparatus  100  may be mounted on a place, on which it is conveniently installed, among an upper portion, a side portion or a rear portion of a drawer-type or 1-box type storage container. 
         [0089]    When the elastic member  130  of the air pressure adjusting apparatus  100  is a spring, a spring constant may be adjusted to allow for opening or closing of the valve (i.e., the air pressure adjusting apparatus  100 ) at a predetermined level of pressure. In addition, it may be possible to implement an apparatus which is open under pressure when the spring constant differs by taking into account a predetermined air pressure which is desired to be maintained in the storage container  1 . 
         [0090]    For example, when the internal air pressure of the storage container  1  is lowered below a reference air pressure of 0.8 atm, the air pressure adjusting apparatus  100  may be open to allow for an introduction of external air. This may prevent the internal air pressure from being lowered below the predetermined air pressure, which is desired to be maintained, and avoid in advance damages such as spoiling, drying and the like of stuffs stored in the storage container  1 . 
         [0091]    In addition, in order to prevent the internal air pressure of the storage container from being lowered below the predetermined air pressure and keeping stuff stored in the storage container under an appropriate air pressure state, the spring constant may be adjusted so as to maintain the predetermined air pressure. 
         [0092]    The air pressure adjusting apparatus  100  according to the present disclosure may be configured to open and close the through hole  103  by moving the elastic member  130  as a spring and the opening/closing portion  111  (rubber button) of the movable member  110 . 
         [0093]    That is, under an appropriate internal air pressure state of the storage container  1 , the opening/closing portion  111  (rubber button) may be pushed up by the force of the spring, namely, the elastic member  130 , to airtightly close the through hole  103 , thereby maintaining the airtight state of the storage container  1 . However, in the state that the internal air pressure of the storage container  1  is lowered below the predetermined air pressure (for example, 0.8 atm), the movable member  110  may be concavely transformed (downwardly curved) by a force of a pressure difference which is greater than the elastic restoring force of the spring, namely, the elastic member  130 , and the opening/closing portion  111  may move downwardly. Accordingly, the through hole  103  may be open to allow for an introduction of external air. Here, the predetermined internal air pressure of the storage container  1  may be set by adjusting the spring constant value. 
         [0094]    Referring to  FIG. 4A , when the difference between the internal air pressure of the storage container  1  and external atmospheric pressure is within the predetermined air pressure range, the spring as the elastic member  130  may press up the opening/closing portion  111  by its elastic restoring force, so as to close the through hole  103 . 
         [0095]    On the other hand, referring to  FIG. 4B , when the internal air pressure of the storage container  1  is lowered below the predetermined air pressure, the deformable portion  113  may be concavely transformed (or downwardly curved) due to the difference between the internal air pressure and the atmospheric pressure. Accordingly, the opening/closing portion  111  may move down to press the elastic member  130 , allowing the elastic member  130  to have an elastic restoring force F k1 . 
         [0096]    After the through hole  103  is open by the movements of the opening/closing portion  111 , external air may be introduced into the storage container  1  via the air holes  113   a  of the movable member  110  and the air holes  153  of the supporting member  150 , thereby raising the internal air pressure of the storage container  1 . When the internal air pressure reaches the predetermined air pressure, the opening/closing portion  111  may then move upwardly by the elastic restoring force of the elastic member  130  to close the through hole  103 , thereby airtightly closing the storage container  1 . 
         [0097]    As described above, the air pressure adjusting apparatus according to one exemplary embodiment may prevent the lowering of the internal air pressure of the storage container below the predetermined air pressure, thereby improving freshness of vegetables stored in the storage container. 
         [0098]    The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments. 
         [0099]    As the present features may be embodied in several forms without departing from the 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 scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.