EP2580548A2

EP2580548A2 - Low-pressure storage unit for refrigeration appliance and refrigeration appliance

Info

Publication number: EP2580548A2
Application number: EP11721526.9A
Authority: EP
Inventors: Jan-Grigor Schubert; Yulei Ding; Jingdong Ma; Feng Tao; Zhenyu Yang; Defei Zhao
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2010-05-28
Filing date: 2011-05-26
Publication date: 2013-04-17
Also published as: CN102261800A; WO2011147899A3; CN102261800B; WO2011147899A2

Abstract

The present invention relates to a low-pressure storage unit for a refrigeration appliance and such a refrigeration appliance. The low-pressure storage unit comprises a housing (40) defining an evacuatable storing chamber (32). According to suggestions of the present invention, the housing (40) comprises at least one first member (11) made of metal and at least one second member (10, 16, 17) made of plastic, and the first member (11) and the second member (10, 16, 17) each form a part of walls of the storing chamber (32).

Description

LOW-PRESSURE STORAGE UNIT FOR REFRIGERATION APPLIANCE AND

REFRIGERATION APPLIANCE FIELD OF THE INVENTION

The present invention relates to a low-pressure storage unit for a refrigeration appliance and a refrigeration appliance having said unit. BACKGROUND

Such a refrigeration appliance is well-known in the prior art, in which refrigeration appliance items can be stored in a low-pressure environment. Said refrigeration appliance generally comprises an evacuable storing chamber, wherein by evacuating gas in the storing chamber off, the air content in the storing chamber is reduced such that the hyperoxidation of foods is weakened to prolong the storing period and quality of the foods.

In a refrigeration appliance disclosed by Chinese patent application CN 103243942A and having an evacuable storing chamber (also called as "a low-pressure chamber" or "a vacuum chamber"), a main body of the low-pressure chamber having a food access opening comprises an external contour, which is formed by resin in a box shape and forms the food access opening and a plate-shaped member made of metal, which member extends along a plurality of wall faces (including the bottom face) of the external contour. In this way, because the external contour that is easy to deform is supported by the plate-shaped member made of metal, the deformation of the external contour under pressure is reduced, such that the air tightness at the access site between the external contour and the low-pressure chamber door is improved.

However, when the endured pressure difference is large, the external contour made of resin is easy to deform and thus the air tightness of the low-pressure chamber is weakened.

Furthermore, although a larger thickness can be adopted to prevent the wall of the storing chamber from deforming, in the case that the external contour made of resin is of a box shape, the larger thickness reduces the thermal conductive effect between the exterior and the interior of the storing chamber, and in this case the cabinet molding process is more complex and the defect rate of finished articles is high. SUMMARY OF THE INVENTION

It is an objective of the present invention to solve at least one of the above-mentioned problems, such that it is possible to provide a low-pressure storage unit having a better air tightness and being easy to be manufactured as well as a refrigeration appliance having said low-pressure storage unit.

To this end, the present invention in one aspect relates to a low-pressure storage unit for a refrigeration appliance, wherein the low-pressure storage unit comprises a housing defining an evacuatable storing chamber, characterized in that the housing comprises at least one first member made of metal and at least one second member made of plastic, and the first member and the second member each form a part of walls of the storing chamber.

Because the first metal member and the second plastic member are used to form different pressure enduring portions of the housing, the pressure strength of the housing can be greatly improved due to the metal member, such that this facilitates reducing a possibility that the housing is deformed and thus gas leakages.

Furthermore, by used of the plastic member that is easy to be molded, a structure (especially a structure that needs be sealed, such as a fluid passage or an associated valve structure or the like) that has a high molding requirement can be arranged on the plastic member in the low-pressure storage unit. This facilitates not only manufacturing but also achieving a high air tightness of the low-pressure storage unit. Further, because the metal member can have a small thickness with a good thermal conductance, even if the plastic member has a large thickness, the thermal conductance of the low-pressure storage unit is not greatly degraded. Furthermore, by appropriately arranging the positions of the first metal member and the second member in the housing and appropriately setting the shapes of the members, it is possible that the second plastic member has a simpler shape than the box/casing shape in the prior art. Even if the second plastic member according to the present invention has a relatively larger thickness, it is prospective that the molding process of the plastic member according to the present invention can be controlled more easily than the one in the prior art. Other individual features or features which are combined with other features so as to be considered as belonging to the characteristic of the present invention are defined in the preferred embodiments described below.

According to a particularly preferred embodiment of the present invention, the housing has at least one fluid passage, by which passage the interior and the exterior of the storing chamber are in fluid communication with each other, and a valve for selectively opening or closing the fluid passage, and the fluid passage is provided on the second member. Because plastic is easier to be molded than metal, in the case that the fluid passage and the associated valve structure need high sealing requirements, they may be constructed precisely on the second member even if they have complex structures.

According to a preferred embodiment of the present invention, among all the walls of the storing chamber, the wall having the maximum area is at least mainly formed by the first member. Because the wall enduring the maximum pressure of the storing chamber in a low-pressure state is mainly or completely made of metal, the pressure strength of the storing chamber can be greatly improved, and any deformation, which causes gas leakaging, of the storing chamber is prevented. According to a preferred embodiment of the present invention, among all the walls of the storing chamber, the wall having the minimum area is at least partially formed by the second member. The wall enduring the minimum pressure of the storing chamber in the low-pressure state is at least partially made of plastic. Because the wall having the minimum area of the storing chamber endures a relatively small pressure as the storing chamber is in the low-pressure state, it is prospective that the wall has a relatively small thickness, is easy to be manufactured and does not cause the leakage of the low-pressure storage unit even if the wall is made of plastic having a relative low material strength. According to a preferred embodiment of the present invention, the low-pressure storage unit is of a flat structure, and a top wall and/or a bottom wall of the storing chamber is/are at least mainly formed by the first member

According to a preferred embodiment of the present invention, a front wall and/or a rear wall and/or a side wall of the storing chamber is/are at least partially formed by the second member.

According to a particularly preferred embodiment of the present invention, a door for opening or closing the storing chamber is formed by the second member. Therefore, some complex structures such as a handle, a gas filling valve or the like can be easily and precisely formed on the door.

According to a preferred embodiment of the present invention, the first member has a thickness less than that of the second member. According to a preferred embodiment of the present invention, the thickness of the first member is not more than 4 millimeters, for example, 2 to 2.5 millimeters. According to a preferred embodiment of the present invention, the thickness of the second member is not less than 5 millimeters, for example, 6 millimeters.

According to a particularly preferred embodiment of the present invention, the metal is steel or aluminum.

According to a preferred embodiment of the present invention, the plastic is composed of polycarbonate (PC) or acrylonitrile-butadiene-styrene (ABS) or a mixture of PC and ABS. According to a particularly preferred embodiment of the present invention, the storing chamber comprises a plurality of interconnected walls mainly or completely formed by the first member. This particularly facilitates the pressure strength of the housing.

According to a preferred embodiment of the present invention, the first member is formed in an integral structure manner, such that any connection clearance in the first metal member can be reduced or even eliminated. Therefore, this facilitates improving the air tightness of the storing chamber.

According to an embodiment that is easy to be implemented of the present invention, the first member is manufactured by bending a steel plate.

According to a preferred embodiment of the present invention, the first member has a jointing seam. According to a preferred embodiment of the present invention, the jointing seam is located on the wall having a minimum area of the plurality of walls formed by the first member. According to a preferred embodiment of the present invention, the jointing seam is located centrally in the wall having the minimum area in the plurality of walls formed by the first member.

According to a preferred embodiment of the present invention, the jointing seam is a welding seam.

According to an alternative embodiment of the present invention, the first member is made of aluminum and is integrally molded by extrusion. According to a preferred embodiment of the present invention, the housing comprises a plurality of independently manufactured second members.

According to a preferred embodiment of the present invention, at least one of the second members is made of a material different from that of the other second members.

According to a preferred embodiment of the present invention, the second member is secured to the first member in an air-tight connection manner, the housing comprises a sealing element located between the second member and the first member, and the second member is provided with a groove for at least partially receiving the sealing element. By providing the groove for receiving the sealing element on the second member that is easy to be molded, the sealing system between the first and second members can be more precisely manufactured, which facilitates improving the air tightness of the low-pressure storage unit. According to a preferred embodiment of the present invention, the first member is of a box-shaped structure and has an opening in at least one side thereof, and the second member is connected to the first member along the opening. On the one hand, the first metal and box-shaped member enables the low-pressure storage unit to have a high-strength box-shaped frame. On the other hand, because the second member is connected to the opening of the box-shaped structure, the first member can support the second member, which facilitates reducing a possibility of the second member deforming. This advantage is particularly prominent in the case that the second member is secured to the first member in such a way that the second member is connected to the entire edge of the opening.

According to a preferred embodiment of the present invention, the second member is of a close-loop and frame-shaped structure and forms a connection frame surrounding the opening.

According to a preferred embodiment of the present invention, the second member has a planar abutting surface for abutting with the door constituting the storing chamber in an air tightness manner.

According to a preferred embodiment of the present invention, the second member encloses the opening to form an entire wall of the storing chamber. According to a preferred embodiment of the present invention, the second member is of an approximately plate-shaped structure, which particularly facilitates controlling the manufacturing process of the second member.

According to a preferred embodiment of the present invention, the rear wall or the side wall of the storing chamber is formed by the second member.

According to a preferred embodiment of the present invention, the low-pressure storage unit comprises a plurality of securing units for securing the second member to the first member, and each securing unit comprises a hole provided in at least one of the first member and the second member, wherein the hole is provided in such a way that the interior and the exterior of the storing chamber are not in fluid communication with each other. Therefore, no additional sealing means is necessary to seal the hole of the securing unit, and the air tightness of the low-pressure storage unit can be more reliable.

Although it is possible that the hole is entirely located inside the storing chamber, according to a preferred embodiment of the present invention, the hole is entirely located outside the storing chamber and thus is isolated from the storing chamber. Therefore, items in the storing chamber cannot be interfered with the securing unit, and thus this facilitates the securing operation of the first and second members.

According to a preferred embodiment of the present invention, the low-pressure storage unit comprises a retractable guide unit, and the guide unit is secured on the first member in such a way that the interior and the exterior of the storing chamber are not in fluid communication with each other.

According to a preferred embodiment of the present invention, the first member is not provided with any through hole that enables fluid communication between the interior and the exterior of the storing chamber.

According to a preferred embodiment of the present invention, the first member forms a main body portion of the housing. The present invention in another aspect relates to a low-pressure storage unit for a refrigeration appliance, wherein the low-pressure storage unit comprises a housing defining an evacuatable storing chamber, characterized in that the housing comprises: a first member made of a first material, wherein the first member forms a main body portion of the housing; and a second member made of a second material, wherein the second member forms a part of the housing, and the modulus of elasticity of the second material is greatly less than that of the first material.

According to a preferred embodiment of the present invention, the first material is metal.

According to a preferred embodiment of the present invention, the first material is steel or aluminum. According to a preferred embodiment of the present invention, the first member is a one-piece structure.

According to a preferred embodiment of the present invention, the second material is plastic, for example, polycarbonate (PC) or acrylonitrile-butadiene-styrene (ABS) or a mixture of PC and ABS.

According to a preferred embodiment of the present invention, the first member has a thickness which is less than that of the second member.

According to a preferred embodiment of the present invention, among all walls of the storing chamber, at least a wall having the maximum area is mainly or completely formed by the first member.

According to a preferred embodiment of the present invention, the low-pressure storage unit comprises at least one fluid passage enabling a fluid communication between the interior and the exterior of the storing chamber and a valve capable of closing the fluid passage, and the fluid passage is provided on the second member. According to a preferred embodiment of the present invention, the low-pressure storage unit comprises a securing unit for securing the first member and the second member, and the securing unit comprises a hole which is provided in at least one of the first member and the second member, wherein the hole is provided in such a way that the interior and the exterior of the storing chamber are not in fluid communication with each other.

According to a preferred embodiment of the present invention, the second member is secured to the first member in an air-tight connection manner, the housing comprises a sealing element located between the second member and the first member, and the second member is provided with a groove for at least partially receiving the sealing element.

According to a preferred embodiment of the present invention, the first member is of a box-shaped structure and has an opening in at least one side thereof, and the second member is connected to the first member along the opening.

According to a preferred embodiment of the present invention, the second member is of an approximately plate-shaped structure, and the opening is enclosed by the second member. According to a preferred embodiment of the present invention, the second material is composed of glass.

The present invention in another aspect relates to a refrigeration appliance, comprising a storage compartment and the low-pressure storage unit as recorded above and received in the storage compartment.

According to a preferred embodiment of the present invention, the refrigeration appliance comprises a gap shielding member for shielding a gap between the housing and an inner wall of the storage compartment.

The configuration of the present invention and other objectives and beneficial effects thereof will be well understood by description of preferred embodiment in accompany of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

As a part of the description and for providing further explanation of the present invent, the drawings illustrate preferred embodiments of the present invention and are used together with the description to explain the principle of the present invention. In the drawings:

Figure 1 shows a schematic perspective view of a refrigeration appliance according to a preferred embodiment of the present invention, wherein a door of the refrigeration appliance is not shown;

Figure 2 shows a schematic assembled perspective view of a low-pressure storage unit according to a preferred embodiment of the present invention; Figure 3 is a schematic perspective view, showing that the low-pressure storage unit according to the preferred embodiment of the present invention is opened;

Figure 4 is a schematic exploded view, showing a main body of the low-pressure storage unit according to the preferred embodiment of the present invention;

Figure 5 is a schematic partial cross-sectional view taken in a direction A-A in figure 2;

Figure 6 is a schematic exploded perspective view of a part of the main body according to a preferred embodiment of the present invention;

Figure 7 is a schematic partial cross-sectional view, showing that a guide unit according to a preferred embodiment of the present invention is secured on the main body;

Figure 8 is a schematic perspective view of a gap shielding member according to a preferred embodiment of the present invention; and

Figure 9 is a schematic partial cross-sectional view, showing that the gap shielding member according to the preferred embodiment of the present invention is mounted between an inner shell and the main body.

DETAILED DESCRIPTION OF THE INVENTION As shown in figure 1 , a refrigeration appliance 1 comprises a thermally insulated cabinet 2, the cabinet 2 including an outer shell 2a, an inner shell 2b and a thermal insulation layer (not shown) therebetween. The cabinet 2 defines a plurality of thermally insulated storage compartments 3, 4 and 5 to store items such as foods. In the present embodiment, these storage compartments are an upper refrigeration compartment 3, a lower freezing compartment 5 and a preservation compartment 4 which is located between the upper and lower compartments and is maintained at a temperature of slightly higher than zero Degree Celsius. These storage compartments 3, 4 and 5 can be closed by respective doors (not shown).

It should be understood that the present invention is not limited by the specific arrangement of the storage compartments of the refrigeration appliance. The present invention can be applied for other types of refrigeration appliance, such as a refrigerator having refrigerating and freezing compartments arranged one above the other, a side-by-side combination refrigerator as well as a refrigerator having a drawer-typed door and/or a French door refrigerator or the like.

The refrigeration appliance 1 has a close-looped evaporative refrigeration system. The refrigeration system comprises at least a compressor (not shown), a condenser (not shown), a throttling device (not shown) and an evaporator (not shown). Since this kind of refrigeration system is well-known in the prior art, its detailed explanation is omitted here.

The refrigeration appliance 1 is provided with a low-pressure storage unit 7, having an evacuable storing chamber 32, and an evacuation device (not shown) for evacuating gas out of the storing chamber 32. The evacuation device can comprise a vacuum pump and a pipeline (not shown) connecting between the vacuum pump and the low-pressure storage unit 7. In the present embodiment, the low-pressure storage unit 7 is provided in the preservation compartment 4. The low-pressure storage unit 7 is located at a bottom of the preservation compartment 4, and is supported on a bottom wall of the preservation compartment 4. In the present embodiment, a preservation container 6 is provided above the low-pressure storage unit 7, which preservation container has a higher humidity and is adapted for storing foods such as vegetables. It should be understood that, in an alternative embodiment, the low-pressure storage unit 7 can be provided in other storage compartments, such as the refrigerating compartment 3 or a variable compartment whose temperature zone can be changed between a refrigerating temperature zone and a freezing temperature zone.

Figurer 2 is a schematic assembly perspective view showing the low-pressure storage unit 7 according to a preferred embodiment of the present invention. Figure 3 is a schematic perspective view showing that the low-pressure storage unit 7 according to the preferred embodiment of the present invention is opened. As shown in figures 2 and 3, in this embodiment, the low-pressure storage unit 7 is generally in the form of a flat rectangular parallelepiped and comprises a main body 8 being opened at one end and a drawer-typed container 9 which is movably received in the main body 8. The main body 8 defines a flat receiving space having a front opening. The drawer-typed container 9, at its front wall, is formed with a door 10 for closing the front opening of the main body 8. A tray-shaped container body 12 is connected at a rear side of the door 10 for storing items. The main body 8 is received and secured in the cabinet 2. It is preferable that the main body 8 is detachably secured in the

preservation compartment 4. A user can draw out the draw-typed container 9 to have access to the items in the low-pressure storage unit 7.

The main body 8 and the door 10 have widths which each are slightly less than the width of the preservation compartment 4. Thus it is ensured that the main body 8 and the door 10 can be inserted into the preservation compartment 4 or be pulled out of the preservation compartment 4. Therefore, gaps can be formed between both sides of the low-pressure storage unit 7 and the inner shell 2b of the preservation compartment 4 respectively. In order to shield these gaps, the low-pressure storage unit 7 can comprise a deformable gap shielding member 50 which is provided at the front end of the main body 8. The detailed configuration of the gap shielding member 50 will be explained in the following.

The low-pressure storage unit 7 has a housing 40 which is constituted by the main body 8 and the door 10 of the drawer-typed container 9. The housing 40 defines the evacuable storing chamber 32, wherein the tray-shaped container body 12 is located in the storing chamber 32. In the present embodiment, the storing chamber 32 is essentially formed by the receiving space of the main body 8. When the storing chamber 32 is closed by the door 10 and the evacuation device is switched on, gas in the storing chamber 32 is evacuated off and the storing chamber 32 is in a low-pressure state. According to a preferred embodiment of the present invention, after the evacuation procedure is completed, the storing chamber 32 has a pressure therein, which pressure is between one standard atmospheric pressure and the absolute vacuum (for example, the absolute vacuum being less than 690 millibars). Because the gas pressure in the storing chamber 32 is less than one standard atmospheric pressure, this chamber can also be called as "a vacuum chamber" by the skilled in the art. In the present embodiment, the storing chamber 32 has a volume of about 20 L.

A sealing element (not shown) can be provided at the front end of the main body 8 and/or at the door 10, such that there is a gas tightness engagement formed between the main body 8 and the door 10 after the drawer-typed container 9 is completely closed. Therefore, gas is prevented from entering into the storing chamber 32 via the engagement site between the main body 8 and the door 10.

A telescopic guide unit 14 is provided between the drawer-typed container 9 and the main body 8, such that the drawer-typed container 9 can be smoothly pulled out of the main body 8 or pushed into the main body 8. The manner how the guide unit 14 is secured to the main body 8 will be particularly explained in the following.

The door 10 is provide with a gas filling passage (not shown), which gas filling passage fluidly communicates with the interior and exterior of the storing chamber 32, and a gas filling valve (not shown) for opening or closing the gas filling passage. When the gas filling passage is opened by the gas filling valve, gas from the exterior can enter into the storing chamber 32 via the gas filling passage such that the low-pressure state of the storing chamber 32 is released. The door 10 is provided with a handle 13 at the front end. The user can operate the drawer-typed container 9 by the handler 13. In one preferred embodiment, the gas filling valve is provided in such a way that it is associated with the handle 13. That is, when the handle 13 is operated, the gas filling valve is opened such that the storing chamber 32 fluidly communicates with the exterior. Therefore, gas can enter into the storing chamber 32 such that the low-pressure state of the storing chamber 32 is released. In an alternative embodiment, the gas filling valve can be provided independently from the handle 13. For example, the door 10 is provided with a button thereon. The gas filling valve is opened by pressing the button. Then, the user can operate the handle 13 to open the door 10.

The door 10, constituting the front wall of the storing chamber 32, is made of plastic which is easily molded, because some complex structures such as the gas filling valve and the handler 13 and so on will be formed. In the present embodiment, the door 10 is made of ABS resin (acrylonitrile butadiene styrene).

The inner surface of the door 10 is exposed to the storing chamber 32, and the outer surface of the door constitutes a part of the external contour of the low-pressure storage unit 7 so as to form a part of the wall of the storing chamber 32. When the storing chamber 32 is in the low-pressure state, the door 10 must endure a pressure difference between the interior and the exterior. However, the tray-shaped container body 12 endures no pressure because it is located in the storing chamber 32.

Therefore, the door 10 has a thickness which is larger than the tray-shaped container body 12. In the present embodiment, the thickness of the door 10 is 6 millimeters, and the tray-shaped container body 12 can have a thickness of about 1 to 2 millimeters.

Figure 4 is a schematic exploded perspective view showing the main body 8 according to a preferred embodiment of the present invention. As shown in figures 2 and 3 by combination with figure 4, the main body 8 comprises a box-shaped box body 11 which is opened at front and rear ends, a rear cover 16 which is secured at the rear end of the box body 11 to close a rear opening 26 of the box body 11 , and a front jointing unit 17, which is secured at an edge of a front opening 25 of the box body 11 .

A sealing element 18 is provided between the box body 11 and the rear cover 16 as well as between the box body 11 and the front jointing unit 17 respectively, such that the box body 11 forms a gas tightness engagement with the rear cover 16 and a gas tightness engagement with the front jointing unit 17 respectively.

In the present embodiment, the box body 11 comprises a top wall 21 , a bottom wall 23, left and right side walls 22 which are connected between the top wall 21 and the bottom wall 32. The top, bottom, left and right side walls are made of metal having a larger material strength. The box body 11 constitutes a main part of the housing 40. In the present embodiment, the top wall 21 , the bottom wall 23 and the left and right side walls 22, all of which are made of metal, are exposed at their inner sides to the storing chamber 32 respectively. Outer surfaces of these walls constitute a part of the external contour of the low-pressure storage unit 7, and constitute a majority of the upper wall, the lower wall and two side walls of the storing chamber 32. The front jointing unit 17 is also exposed at its inner side to the storing chamber 32. Therefore, it constitutes a minority of the upper boundary, the lower boundary and the two side boundaries of the storing chamber 32. When the storing chamber 32 is in the low-pressure state, the box body 11 , the front jointing unit 17 and the rear cover 16 endure a pressure caused by the pressure in the storing chamber 32 being less than the pressure of the exterior. It should be understood that, in an alternative embodiment, it is also possible that all of the upper, lower and two side walls of the storing chamber 32 are completely formed by the box body 11 made of metal.

The top wall 21 , the bottom wall 23 as well as the left and right side walls 22 can be produced by a metal sheet, whose thickness is not more than 4 millimeters. Preferably, the thicknesses of these walls 21 -23 are 2 millimeters to 2.5 millimeters.

The top wall 21 , the bottom wall 23 as well as the left and right side walls 22 of the box body 11 are preferably formed in a one-piece structure, such that any jointing seam between these walls can be reduced or even eliminated. In the present embodiment, the top wall 21 , the bottom wall 23 as well as the left and right side walls 22 are formed by a piece of metal sheet (cold rolled plate), which is bent into a rectangular shape and then is welded. As shown in figures 3 and 4, a welding seam 33 is located at the middle site of the right side wall 22. On the one hand, because the side wall 22 endures a less pressure than the top wall 21 and the bottom wall 23, this may facilitate reducing a possibility that air leakage occurs at the welding seam 33 under pressure. On the other hand, this may also facilitate arranging a clamp during the welding procedure.

Furthermore, because the welding seam is located at a side wall which cannot be readily noticed by the user, this may facilitate achieving a better aesthetic of the refrigeration appliance 1 .

It should be understood that, in an alternative embodiment, it is also possible that the top wall 21 , the bottom wall 23 as well as the left and right side walls 22 of the box body 11 are formed by a plurality of metal sheets, which are jointed (such as welded) together. Furthermore, the box body 11 can also be made of other metal such as aluminum. On the case that the box body is made of aluminum, the box body is preferably achieved by an integrally extruding procedure. Because the modulus of elasticity of aluminum is less than that of steel, it is preferable that the box body made of aluminum has a thickness of lager than 2 millimeters, for example being 4 millimeters.

In the present embodiment, the top wall 21 is symmetrical to the bottom wall 23. The two walls constitute a majority of the total wall area of the box body 11. When the low-pressure storage unit 7 is in a low-pressure state, the top wall 21 and the bottom wall 23 endure more pressure than the other walls of the low-pressure storage unit 7. In order to increase moments of inertia of the top wall 21 and the bottom wall 23, the top wall 21 and the bottom wall 23 each are stamped with a plurality of protruding zones 34 which protrude outwards.

According to a preferred embodiment of the present invention, as shown in figures 3, 4 and 5, mounting plates 27 are provided at the front and rear ends of the box body 11 and at outer sides of the top wall 21 , the bottom wall 23 as well as the left and right side walls 22, such that no through hole needs be provided on the top wall 21 , the bottom wall 23 as well as the left and right side walls 22 to secure the front jointing unit 17 and the rear cover 6 to the box body 11. The mounting plates 27 can be made of metal, for example made by steel sheets.

Each mounting plate 27 comprises a jointing foot 27a, which is horizontally secured on a corresponding one of the walls 21 to 23. In the present embodiment, the mounting plate 27 is secured on the box body 11 by welding the jointing foot 27a to the corresponding one of the walls 21 to 23. In an alternative embodiment, the mounting plate 27 can be secured on the box body 11 in other ways, for example is adhered on the box body 11. The mounting plate 27 comprises an extension 27b, which folds from the jointing foot 27a and then extends outwards. In the present embodiment, the extension 27b is substantially perpendicular to the corresponding one of the walls 21 to 23. The extension 27b has a plate shape. It has planar front and rear surfaces. The extensions 27b at the front and rear ends of the box body 11 each are at a distance from the front and rear end faces of the box body 11.

In the present embodiment, the mounting plate 27 has an L-shape in its cross-section, which is formed by the extension 27b and the jointing foot 27a. However, in an alternative embodiment, the extension 27b can be formed integrally on the

corresponding one of the walls 21 to 23 such that the extension extends outwards directly from the corresponding one of the walls 21 to 23 of the box body 11 . Each extension 27b is provided with a plurality of first holes 31 a which extend all the way through the front and rear surfaces of the extension. Preferably, the first holes 31 a of each extension 27b are arranged at a predetermined interval with each other, and they are arrayed in a row. The first holes 31 a located at the front and rear ends of the box body 11 each form a rectangular frame, whose size is larger than the front/rear opening 25, 26. The corresponding rectangular frame encloses the box body 11 therein. The first holes 31 a at the rear end of the box body 11 are threaded. However, the first holes 31 a at the front end of the box body 11 are not threaded.

The rear cover 16 and the front jointing unit 17 according to a preferred embodiment of the present invention are particularly explained in their structures in detail below.

The rear cover 16 is connected to the rear opening 26 of the box body 11 , constitutes the rear wall of the housing 40 and delimits the rear boundary of the storing chamber 32. The rear cover 16 is in the form of a square plate, which corresponds to the rear opening 26. The rear cover 16 has a size which is larger than that of the rear opening 26. The rear cover 16 extends beyond the rear opening 26.

The rear cover 16 is provided with an evacuation passage (not shown) extending through the rear cover 16 and an evacuation valve unit 36 for selectively closing or opening the evacuation passage. In the present embodiment, the evacuation valve unit 36 extends above the top wall 21 , and has a jointing opening 39 above the top wall 21 . The low-pressure storage unit 7 connects with a pipeline secured on the cabinet 2 via the jointing opening 39, such that the low-pressure storage unit 7 can fluidly communicate with the evacuation device.

The rear cover 16 comprises a main wall portion 20 constituting the most part of the rear cover and a rear jointing portion 19, which is provided around the main wall portion 20 and connects the rear cover 16 to the edge of the rear opening 26. The rear jointing portion 19 connects with the entire edge of the rear opening 26.

In the present embodiment, the rear jointing portion 19 and the main wall portion 20 are produced by integral injection molding of plastic, whose modulus of elasticity is less than metal. Preferably, the rear cover 16 is made of material having a larger material strength, such as polycarbonate (PC). The main wall portion 20 made of PC has a thickness of about 6 millimeters. In order to enhance the strength of the main wall portion 20, the main wall portion 20 is provided with a plurality of reinforcing ribs 35 on its rear surface. It should be understood that, in an alternative embodiment, the rear jointing portion 19 and the main wall portion 20 can be provided independently with each other, and then they are airtightly secured to form the rear cover 16. This will be particularly beneficial in the case that the rear jointing portion 9 and the main wall portion 20 are made of different materials. The front jointing unit 17 connects at the entire edge of the front opening 25, and has a square framed structure forming a close-loop. The front jointing unit 17 has an abutting face 37 for abutting with the door 10. In the present embodiment, the abutting face 37 is planar, and is in the same longitudinal plane. When the door 10 is closed, the sealing element on the door 10 is pressed between the abutting face 37 and the door 10 to make a sealing effect.

In order that the front jointing unit 17 and the rear cover 16 are airtightly connected on the box body 11 respectively, the front jointing unit 17 and the rear cover 16 each are provided with a ring-shaped groove 30 at a side facing the box body 11 , which groove is used to receive a ring-shaped sealing element 18. The front and rear ends of the top wall 21 , the side walls 22 and the bottom wall 23 of the box body 11 each are inserted into the corresponding groove 30. The sealing element 18 is located between the groove 30 and the box body 11 .

Outside of the groove 30, the front jointing unit 17 and the rear cover 16 each are provided with a plurality of second holes 31 b. These second holes 31 b are provided on the outer surface portions of the front jointing unit 17 and the rear jointing unit 19 beyond the top wall 21 , the side walls 22 and the bottom wall 23, and are located outside of the storing chamber 32. The second holes 31 b on the front jointing portion 17 and the rear cover 16 form rectangular frames respectively, each of which rectangular frames has a size which is larger than the front/rear opening 25, 26. In the present embodiment, the second holes 31 b on the front jointing unit 17 extend forwards from the rear side of the front jointing unit 17, do not extend through the front jointing unit 17 and thus form blind holes, which are threaded therein for attaching screws 29. The second holes 3 b on the rear cover 16 extend forwards from the rear side of the rear jointing portion 19, through the rear jointing portion 19 and form through holes to be inserted through by corresponding screws 29.

The front jointing unit 17 is formed by integral injection molding of plastic. In the present embodiment, because the front jointing unit 17 is provided with the threaded holes for attaching the screws 29, the front jointing unit 17 is formed from a mixture of PC resin having a larger strength and ABS resin having a better toughness by injection molding, such that the strength and the toughness of the unit is balanced.

The securing manner between the front jointing unit 17, the rear cover 16 and the box body 11 will be particularly explained below.

The front jointing unit 17 and the rear cover 16 are secured on the front and rear ends of the box body 11 by a plurality of securing units respectively. In the present embodiment, each securing unit comprises the screw 29, the first hole 31 a provided on the mounting plate 27 of the box body 11 and the second hole 31 b provided on the front jointing unit 17/the rear cover 16. By inserting the screw 29 into the first hole 31 a and the second hole 31 b and then screwing the screw 29 with the threaded first hole 31 a or the threaded second hole 31 b, the front jointing unit 17/the rear cover 16 each can be reliably secured on the box body 11 . By use of the screw 29, the securing unit provides a pretension force between the front jointing unit 17 and the box body 11 as well as between the rear cover 16 and the box body 11 , such that the sealing elements 18 located between the front jointing unit 17/the rear cover 16 and the box body 11 can be pressed and thus the sealing effect between the front jointing unit 17/the rear cover 16 and the box body 11 can be enhanced.

In an alternative embodiment, the securing unit can adopt another securing piece which can provide the pretension force. For example, the screw can be replaced by a rod-shaped piece which is integrally injection molded on the front jointing unit 17 and the rear cover 16. In this case, the second holes 31 b on the jointing frame 17 and the rear cover 16 can be omitted.

In the present embodiment, because all of the first holes 31 a and the second holes 31 b are located outside of the storing chamber 32, the interior of the storing chamber 32 cannot fluidly communicate with the exterior due to the arrangement of the first holes 31 a and the second holes 31 b. Furthermore, because the first holes 31 a and the second holes 31 b are located outside of the ring-shaped sealing element 18, the first holes 31 a and the second holes 31 b is in fact separated from the storing chamber 32 and does not communicate with it. In this way, a possibility that gas from the exterior enters into the storing chamber 32 via the first holes 31 a and the second holes 31 b is eliminated. That is, these first and second holes 31 a, 31 b cannot have a negative effect on the air tightness of the storing chamber 32, such that the air tightness of the low-pressure storage unit 7 is improved.

The manner how the retractable guide unit 14 is secured on the box body 11 will be explained in detail below.

As shown in figures 3, 6 and 7, each guide unit 14 comprises a fixing rail 14a fixed to the box body 11 , a moving rail 14b fixed to the drawer-typed container 9 and a rolling unit disposed between the fixing rail 14a and the moving rail 14b. The rolling unit can comprise several balls or one or more roller wheels or the like.

The guide unit 14 is located within the storing chamber 32 between an inner side of a corresponding side wall 22 and an outer side of the tray-shaped container body 12. Particularly, the fixing rail 14a is fixed to the inner side of the box body 11 , and the moving rail 14b is fixed to the outer side of the tray-shaped container body 12.

The low-pressure storage unit 7 comprises a securing device for securing the fixing rail 14a on the box body 11 . In the present embodiment, the securing device comprises a screw 41 , a housing hole 42 on the box body 11 and a guide hole 43 on the fixing rail 14a. The housing hole 42 is threaded therein to secure the screw 41 . In the present embodiment, the guide hole 43 is a through hole. The screw 41 is inserted though the guide hole 43 and into the housing hole 42, and then is engaged with the threaded housing hole 42, such that the fixing rail 14a is secured on the inner side of the side wall 22 of the box body 11 .

According to a preferred embodiment of the present invention, although the securing device comprises the hole, the hole is not provided to extend all the way through the side wall 22, that is, the storing chamber 32 cannot be in fluid communication with the fluid from the exterior due to the securing device.

For this reason, the securing device comprises a mounting piece 44 which is secured to the inner side of the side wall 22 and is located in the storing chamber 32. The mounting piece 44 comprises a mounting portion 45 provided with the housing hole 42. A gap is formed between the mounting portion 45 and the inner surface of the side wall 22. Both ends of the housing hole 42 are exposed to the storing chamber 32, and are entirely located inside the storing chamber 32. Therefore, the storing chamber 32 is not in fluid communication with the fluid from the exterior due to the housing hole 42.

Preferably, an end of the screw 41 is protruded into the gap between the side wall 22 and the mounting portion 45, but is not in contact with the side wall 22.

The mounting piece 44 comprises a pair of feet 46 each of which is connected to each corresponding side of the mounting portion 45. The mounting piece 44 is secured on the inner surface of the side wall 22 by the feet 46. In the present embodiment, the feet 46 are welded on the side wall 22. In an alternative embodiment, the feet 46 can also be secured on the side wall 22 in another manner such as bonded, such that the side wall 22 is not penetrated. It should be understood that, it is also possible that the mounting piece is formed integrally on the side wall.

In order to enlarge the gap between the inner surface of the side wall 22 and the mounting portion 45, it is preferable that the side wall 22, at a location corresponding to the mounting portion 45, is provided with a depression 47 which is depressed outwardly to form a depression space. Additionally, the mounting portion 45 can also be of a thin U-shaped structure, such that the bottom of the U-shape of the mounting portion 45 is more far away from the corresponding side wall 22. The gap shielding member 50 will be explained in detail with respect to figures 2, 3, 6, 8 and 9.

A gap G exists between the front jointing frame 17 and the inner shell 2b of the cabinet 2. Some structures (such as a mounting structure for securing the main body 8 on the inner shell 2b) between the inner shell 2b and the main body 8 can be noticed by the user. This influences the impression of the user to the refrigeration appliance 1 , and the gap G itself does not facilitate the aesthetic. Therefore, according to a preferred embodiment of the present invention, the refrigeration appliance 1 comprises the gap shielding member 50, which is located between the front part of the low-pressure storage unit 7 and the inner shell 2b to shield the gap G in front of the main body 8.

The gap shielding member 50 is in the form of an elongated strip and mounted on a corresponding side of the front jointing frame 17. In the present embodiment, one gap shielding member 50 is provided on each of both longitudinal sides of the front jointing frame 17. In an alternative embodiment, the gap shielding member 50 is only provided on one side of the front jointing frame 17, or it is also possible that each of four sides of the front jointing frame 17 is provided with the gap shielding member 50.

The gap shielding member 50 comprises a rigid securing part 51 , which is used to secure the gap shielding member 50 on the front jointing frame 17, and a flexible covering part 52, which extends from the securing part 51 to cover the gap G In the present embodiment, the gap shielding member 50 is an extruded member, wherein the securing part 51 and the covering part 52 are integrally extrusion molded.

The securing part 51 has a first clipping wall 53 and a second clipping wall 54, which are provided opposed to each other, and a connecting wall 55, which connects between the first clipping wall 53 and the second clipping wall 54. The first clipping wall 53, the second clipping wall 54 and the connecting wall 55 together define a clipping slot 56, which opens at one side. In the present embodiment, the first clipping wall 53 has a lateral width, which is larger than that of the second clipping wall 54. Preferably, the securing part 51 extends over the length of the gap shielding member 50. The securing part 51 also comprises a hook 57 on each of the first and second clipping walls, wherein the hook 57 folds from an end of a corresponding one of the first and second clipping walls 53 and 54 towards the other of the first and second clipping walls 53 and 54.

The covering part 52 connects with the first clipping wall 53 at one end and extends in a direction far away from the clipping slot 56. The front surfaces of the covering part 52 and of the first clipping wall 53 are in the same plane. The covering part 52 extends over the length of the gap shielding member 50.

The covering part 52 is provided on the gap shielding member 50 as a limb. Along a direction from the end of the covering part that connects with the first clipping wall 53 to a free end of the covering part, the covering part 52 has a gradually decreasing thickness and thus is elastically deformable.

After the piece is mounted on the front jointing frame 17, the side end of the front jointing piece 17 is clipped in the clipping slot 56, wherein the first clipping wall 53 is abutted immediately against the front face of the front jointing frame 17, and the second clipping wall 54 is abutted immediately against the rear face of the front jointing frame 17. In order to flush the front surface of the first clipping wall 53 with the abutting face 37 of the front jointing frame 17, a depression zone is formed on each of two side ends of the front surface of the front jointing frame 17 respectively, the depth of which depression zone corresponds substantially to the thickness of the first clipping wall 53.

Furthermore, a step is formed on the front and rear surfaces of the front jointing frame 17 respectively, which step corresponds to the hook 57. The hook 57 is hooked on the step such that the gap shielding member 50 is prevented from falling off from the front jointing frame 50.

Before being inserted into the preservation compartment 4, the main body 8 provided with the gap shielding member 50, at the plane where the front surface of the covering part 52 locates, has a lateral width, which is larger than that of the preservation compartment 4. After the main body 8 is completely inserted into the preservation compartment 4, the covering part 52 is pressed by the inner shell 2b, thus is deformed and is abutted against the inner shell 2b. In this way, the gap G and some structures behind the front jointing frame 17 can be shielded by the covering part 52. Therefore, when the door 10 is opened, the user can notice a more clean and neat appearance.

In the embodiment of the present invention, the housing 40 of the low-pressure storage unit 7 comprises a first member (such as the box body 11 ), which is made of metal having a larger material strength, and a plurality of second members (such as the front jointing unit 17, the rear cover 16 and the door 10), which are made of plastic, which has a relatively smaller material strength and is easy to be molded. Therefore, on the one hand, the first member can obtain a larger strength by a smaller thickness to endure the exterior pressure, such that any deformation of the storing chamber 32 in the low-pressure state can be reduced so as to improve the air tightness of the storing chamber 32. This advantage is particularly prominent in the case that the walls (such as the top wall 21 and the bottom wall 23) of the storing chamber 32 occupying the largest area are mainly or completely made of metal. Especially, when the housing 40 is mainly made of metal, this advantage is particularly prominent. On the other hand, because the housing comprises the second members (such as the front jointing unit 17, the rear cover 16 and the door 10), which are made of plastic and endure the pressure when the storing chamber 32 is in the low-pressure state, provided on these second members can be relatively complex, high accuracy requiring and perfect air tightness requiring structures (such as a perfect air tightness requiring gas filling valve, an evacuation valve unit and so on) so as to improve the air tightness of the low-pressure storage unit. Further, because the first member made of metal can have a smaller thickness and a good thermal conductibility, heat can be well conducted between the exterior and the interior of the storing chamber even if the second member has a larger thickness. Furthermore, when the second members constitute only a small portion of the housing and especially they are not provided in a box-shaped structure, the molding process of them is relatively easy. Meanwhile, because they are only the small portion of the low-pressure storage unit 7, they do not have a significant effect on the heat conducting between the exterior and the interior of the low-pressure storage unit 7.

It can be seen that, by constructing the housing by different members made of different materials, an improved air tightness can be obtained by the producer and it is prospective that the low-pressure storage unit is easy to be manufactured. Furthermore, in the embodiment of the present invention, a box-shaped structure with an opening is formed by the top wall, the bottom wall, the left side wall and the right side wall, which are made of metal, of the box body 11 . The front jointing unit and the rear cover, which are made of plastic, are secured on the box body along the opening. That is, the front jointing unit and the rear cover can be supported by a metal frame having a large strength, which facilitates reducing any deformation of the front jointing unit and the rear cover under pressure.

Furthermore, in the embodiment of the present invention, a plurality of protruding regions 34 are provided on each of the top wall 21 and the bottom wall 23 occupying the majority area. By the special arrangement of the protruding regions 34, the strength of the box body 11 is improved.

Furthermore, in the embodiment of the present invention, a fluid passage (such as the gas filling passage and the evacuation passage), by which the interior and the exterior of the storing chamber 32 are in fluid communication with each other, can be provided on a member (such as the door or the rear cover) made of plastic of the housing 40. Because plastic is easy to be molded, the designer can design a gas passage and an associated valve structure which are more complexly and precisely constructed, such that the air tightness of the fluid passage as being closed can be improved.

Furthermore, in the embodiment of the present invention, although the securing unit for securing the independently constructed box body, front jointing frame and rear cover makes the securing by use of the hole, the hole is provided in such a way that the evacuable storing chamber is not in fluid communication with the fluid from the exterior. This improves the air tightness of the housing which is formed by several members being secured together to define the storing chamber.

It should be understood that, although in the above embodiments the top wall, bottom wall, the left and right side walls of the evacuable storing chamber are mainly or completely formed by a metal member, the present invention is not limited by this. For example, in an alternative embodiment, the top wall, the bottom wall, one side wall and the rear wall of the housing for defining the evacuable storing chamber are mainly or completely made of metal, but the other side wall of the evacuable storing chamber can be made of plastic. In another embodiment, the top wall, the left and right side walls of the housing are mainly or completely made of metal, the rear wall is made of plastic, and the rear wall can be at least partially made of transparent glass whose modulus of elasticity is between those of metal and plastic.

Claims

1. A low-pressure storage unit (7) for a refrigeration appliance (1 ), wherein the low-pressure storage unit (7) comprises a housing (40) defining an evacuatable storing chamber (32), characterized in that the housing (40) comprises at least one first member (11 ) made of metal and at least one second member (10, 16, 17) made of plastic, and the first member (11 ) and the second member (10, 16, 17) each form a part of walls of the storing chamber (32).

2. The low-pressure storage unit (7) according to claim 1 , characterized in that the housing (40) has at least one fluid passage, by which passage the interior and the exterior of the storing chamber (32) are in fluid communication with each other, and a valve (36) for selectively opening or closing the fluid passage, and that the fluid passage is provided on the second member (10, 16).

3. The low-pressure storage unit (7) according to claim 1 or 2, characterized in that among all the walls of the storing chamber (32), the wall (21 , 22) having the maximum area is at least mainly formed by the first member (11 ).

4. The low-pressure storage unit (7) according to claim 1 , 2 or 3, characterized in that among all the walls of the storing chamber (32), the wall (10, 16) having the minimum area is at least partially formed by the second member (10, 16, 17).

5. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the low-pressure storage unit (7) is of a flat structure, and a top wall (21 ) and/or a bottom wall (22) of the storing chamber (32) is/are at least mainly formed by the first member (11 ).

6. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that a front wall and/or a rear wall (16) and/or a side wall of the storing chamber (32) is/are at least partially formed by the second member (10, 16).

7. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that a door (10) for opening or closing the storing chamber (32) is formed by the second member (10).

8. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the first member (11 ) has a thickness less than that of the second member (10, 16).

9. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the thickness of the first member (11 ) is not more than 4 millimeters, for example, 2 to 2.5 millimeters.

10. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the thickness of the second member (20) is not less than 5 millimeters, for example, 6 millimeters.

11 . The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the metal is steel or aluminum.

12. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the plastic is composed of polycarbonate (PC) or

acrylonitrile-butadiene-styrene (ABS) or a mixture of PC and ABS. 3. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the storing chamber (32) comprises a plurality of interconnected walls (21 , 22, 23) mainly or completely formed by the first member (11 ).

14. The low-pressure storage unit (7) according to claim 13, characterized in that the first member (11 ) is formed in an integral structure manner.

15. The low-pressure storage unit (7) according to claim 13 or 14, characterized in that the first member (11 ) is manufactured by bending a steel plate.

16. The low-pressure storage unit (7) according to claim 13, 14 or 15, characterized in that the first member (11 ) has a jointing seam (33).

17. The low-pressure storage unit (7) according to claim 16, characterized in that the jointing seam (33) is located on the wall having a minimum area of the plurality of walls (21 , 22, 23) formed by the first member (11 ).

18. The low-pressure storage unit (7) according to claim 17, characterized in that the jointing seam (33) is located centrally in the wall (23) having the minimum area in the plurality of walls (21 , 22, 23) formed by the first member (11 ).

19. The low-pressure storage unit (7) according to claim 16, 17 or 18, characterized in that the jointing seam (33) is a welding seam.

20. The low-pressure storage unit (7) according to claim 13 or 14, characterized in that the first member (11 ) is made of aluminum and is integrally molded by extrusion.

21 . The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the housing (40) comprises a plurality of independently manufactured second members (10, 16, 17).

22. The low-pressure storage unit (7) according to claim 21 , characterized in that at least one of the second members (10, 16, 17) is made of a material different from that of the other second members (10, 16, 17).

23. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the second member (16, 17) is secured to the first member (11 ) in an air-tight connection manner, the housing (40) comprises a sealing element (18) located between the second member (16, 17) and the first member (11 ), and the second member (16, 17) is provided with a groove (30) for at least partially receiving the sealing element (18).

24. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the first member (11 ) is of a box-shaped structure and has an opening (25, 26) in at least one side thereof, and that the second member (16, 17) is connected to the first member (11 ) along the opening (25, 26).

25. The low-pressure storage unit (7) according to claim 24, characterized in that the second member (16, 17) is secured to the first member (11 ) in such a way that the second member is connected to the entire edge of the opening (25, 26).

26. The low-pressure storage unit (7) according to claim 24 or 25, characterized in that the second member (17) is of a close-loop and frame-shaped structure and forms a connection frame surrounding the opening (25).

27. The low-pressure storage unit (7) according to claim 26, characterized in that the second member (17) has a planar abutting surface (37) for abutting with the door (10) constituting the storing chamber (32) in an air tightness manner.

28. The low-pressure storage unit (7) according to claim 24 or 25, characterized in that the second member (16) encloses the opening (26) to form an entire wall of the storing chamber (32).

29. The low-pressure storage unit (7) according to claim 28, characterized in that the second member (10, 16) is of an approximately plate-shaped structure.

30. The low-pressure storage unit (7) according to claim 28 or 29, characterized in that the rear wall or the side wall of the storing chamber (32) is formed by the second member (16).

31. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the low-pressure storage unit (7) comprises a plurality of securing units for securing the second member (16, 17) to the first member (11 ), and each securing unit comprises a hole (31 a, 31 b) provided in at least one of the first member (11 ) and the second member (16, 17), wherein the hole (31 a, 31 b) is provided in such a way that the interior and the exterior of the storing chamber (32) are not in fluid communication with each other.

32. The low-pressure storage unit (7) according to claim 31 , characterized in that the hole (31 a, 31 b) is entirely located outside the storing chamber (32) and thus is isolated from the storing chamber (32).

33. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the low-pressure storage unit (7) comprises a retractable guide unit (14), and the guide unit (14) is secured on the first member (11 ) in such a way that the interior and the exterior of the storing chamber (32) are not in fluid communication with each other.

34. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the first member (11 ) is not provided with any through hole that enables fluid communication between the interior and the exterior of the storing chamber (32).

35. The low-pressure storage unit (7) according to any one of the preceding claims, characterized in that the first member (11 ) forms a main body portion of the housing (40).

36. A low-pressure storage unit (7) for a refrigeration appliance (1 ), wherein the low-pressure storage unit (7) comprises a housing (40) defining an evacuatable storing chamber (32), characterized in that the housing (40) comprises:

a first member (11 ) made of a first material, wherein the first member (11 ) forms a main body portion of the housing (40); and

a second member (10, 16, 17) made of a second material, wherein the second member (10, 16, 17) forms a part of the housing (40), and the modulus of elasticity of the second material is greatly less than that of the first material.

37. The low-pressure storage unit (7) according to claim 36, characterized in that the first material is metal.

38. The low-pressure storage unit (7) according to claim 36 or 37, characterized in that the first material is steel or aluminum.

39. The low-pressure storage unit (7) according to claim 37, 38 or 39, characterized in that the first member (11 ) is a one-piece structure.

40. The low-pressure storage unit (7) according to any one of claims 36 to 39, characterized in that the second material is plastic, for example, polycarbonate (PC) or acrylonitrile-butadiene-styrene (ABS) or a mixture of PC and ABS.

41. The low-pressure storage unit (7) according to any one of claims 36 to 40, characterized in that the first member (11 ) has a thickness which is less than that of the second member (10, 16, 17).

42. The low-pressure storage unit (7) according to any one of claims 36 to 41 , characterized in that among all walls of the storing chamber (32), at least a wall having the maximum area is mainly or completely formed by the first member (11 ).

43. The low-pressure storage unit (7) according to any one of claims 36 to 42, characterized in that the low-pressure storage unit (7) comprises at least one fluid passage enabling a fluid communication between the interior and the exterior of the storing chamber (32) and a valve (36) capable of closing the fluid passage, and that the fluid passage is provided on the second member (10, 16).

44. The low-pressure storage unit (7) according to any one of claims 36 to 43, characterized in that the low-pressure storage unit comprises a securing unit for securing the first member (11 ) and the second member (16, 17), and the securing unit comprises a hole (31 a, 31 b) which is provided in at least one of the first member (11 ) and the second member (16, 17), wherein the hole (31a, 31 b) is provided in such a way that the interior and the exterior of the storing chamber (32) are not in fluid communication with each other.

45. The low-pressure storage unit (7) according to any one of claims 36 to 44, characterized in that the second member (16, 17) is secured to the first member (11 ) in an air-tight connection manner, the housing (40) comprises a sealing element (18) located between the second member (16, 17) and the first member (11 ), and the second member ( 6, 7) is provided with a groove (30) for at least partially receiving the sealing element (18).

46. The low-pressure storage unit (7) according to any one of claims 36 to 45, characterized in that the first member (11 ) is of a box-shaped structure and has an opening (25, 26) in at least one side thereof, and that the second member (16, 17) is connected to the first member (11 ) along the opening (25, 26).

47. The low-pressure storage unit (7) according to claim 46, wherein the second member (17) is of a close-loop and frame-shaped structure and forms a connection frame surrounding the opening (25).

48. The low-pressure storage unit (7) according to claim 46, characterized in that the second member (16) is of an approximately plate-shaped structure, and that the opening (26) is enclosed by the second member (16).

49. The low-pressure storage unit (7) according to any one of claims 36 to 39, characterized in that the second material is composed of glass.

50. A refrigeration appliance (1 ), comprising a storage compartment (4) and a low-pressure storage unit (7) according to any one of the preceding claims received in the storage compartment (4).

51 . The refrigeration appliance (1 ) according to claim 50, characterized in that it comprises a gap shielding member (50) for shielding a gap (G) between the housing (40) and an inner wall (2b) of the storage compartment (4)