EP2577196A2

EP2577196A2 - Storage unit and household appliance having the same

Info

Publication number: EP2577196A2
Application number: EP11725015.9A
Authority: EP
Inventors: 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: 2013-04-10
Anticipated expiration: 2031-05-26
Also published as: EP2577196B1; CN102261802A; WO2011147897A3; WO2011147897A2; CN102261802B

Abstract

The present invention relates to a storage unit and a household appliance having said storage unit. The storage unit comprises a main body (8) having a receiving space (32); a storage member (9) movably received in the receiving space (32); a retractable guide unit (14) connected between the main body (8) and the storage member (9) for guiding the storage member (9) to insert into and retreat from the receiving space (32); and a securing unit for securing the guide unit (14) to an inner side of a wall (22) of the receiving space (32), wherein the securing unit comprises at least one hole (42) provided on the main body (8) and an insertion member (41 ) passing through and being secured to the hole (42). According to suggestions of the present invention, the securing unit is provided such that the interior of the receiving space (32) is not in fluid communication with the exterior thereof.

Description

STORAGE UNIT AND HOUSEHOLD APPLIANCE HAVING THE SAME

FIELD OF THE INVENTION The present invention relates to a storage unit and a household appliance having said storage unit, more particularly to a storage unit having a retractable guide unit and a household appliance, such as a refrigeration appliance, having said storage unit.

BACKGROUND

A household appliance comprising a storage unit equipped with a retractable guide unit is well-known in the prior art. For example, in a refrigerator, the retractable guide unit can respectively be provided between both sides of a drawer-typed storage container and the corresponding sides of a cabinet so as to guide the retracting movement of the storage container. The guide unit generally comprises a fixing rail fixed at a side of the cabinet, a moving rail fixed at a side of the storage container and a rolling unit, such as a ball / a roller wheel, between the fixing rail and the moving rail. In the prior art, in order to secure the fixing rail or the like, a through hole is necessarily formed on an inner shell of the cabinet, such that a screw for securing the fixing rail can be passed through the inner shell and then secures the fixing rail on the inner shell. Before the foaming procedure of the cabinet is carried out, the through hole must be sealed by the manufacturer such that the foaming agent is prevented from leaking through the through hole. Furthermore, Chinese patent application CN1013243942A discloses a refrigeration appliance having an evacuable storing chamber (a low-pressure chamber). A low-pressure storage unit defining the evacuable storing chamber can comprise a low-pressure chamber main body secured in the storing chamber of the cabinet and a drawer-typed container which is retractably received in the low-pressure chamber main body. If a guide unit is provided on the low-pressure storage unit, a technical problem confronted by the designer is how to ensure the air tightness of the low-pressure chamber. SUMMARY OF THE INVENTION

It is an objective of the present invention to solve at least one of the above technical problems so as to obtain a storage unit, in which the retractable guide unit can be reliably secured and meanwhile a securing unit for securing the guide unit needs no additional sealing means, and a household appliance having said storage unit.

To this end, the present invention in one aspect relates to a storage unit, comprising: a main body having a receiving space; a storage member movably received in the receiving space; a retractable guide unit connected between the main body and the storage member for guiding the storage member to insert into and retreat from the receiving space; and a securing unit for securing the guide unit to an inner side of a wall of the receiving space, wherein the securing unit comprises at least one hole provided in the main body and an insertion member extending through and being secured to the hole; characterized in that the securing unit is provided such that the interior of the receiving space is not in fluid communication with the exterior thereof.

Because the securing unit implements the securing in such a way that the receiving space is not in fluid communication with a fluid from the exterior, no additional sealing means needs be adopted. The present invention is more reliable than the traditional technical solution adopting sealing means. This advantage is more prominent for the storage unit having a strict sealing requirement.

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 will be described in the attached claims.

According to a preferred embodiment of the present invention, the hole is a through hole, both ends of the hole are exposed to the receiving space, and the hole is entirely inside the receiving space.

According to a preferred embodiment of the present invention, the main body comprises a mounting piece located in the receiving space, the mounting piece comprises a mounting portion provided with the hole, and a gap is formed between the mounting portion and an inner surface of the wall.

According to a preferred embodiment of the present invention, the wall is depressed outwardly at a location corresponding to the mounting portion. According to a preferred embodiment of the present invention, the mounting piece comprises a connection portion for connecting the wall with the mounting portion, and the mounting portion is closer to the storage member than the connection portion.

According to a preferred embodiment of the present invention, the mounting portion is U-shaped.

According to a preferred embodiment of the present invention, the insertion member extends into the gap and is at a distance from the wall. According to a preferred embodiment of the present invention, the mounting piece is constructed independently from the wall and is then secured to the inner side of the wall.

According to a preferred embodiment of the present invention, the mounting piece is welded or bonded to the wall.

In an alternative embodiment, the mounting piece is formed integrally on the wall. According to a preferred embodiment of the present invention, the securing unit comprises a guide hole provided in the guide unit, the insertion member is inserted through the guide hole and then extends into the hole, and the securing unit secures the guide unit to the main body in a screwed manner. According to a preferred embodiment of the present invention, the receiving space is air-tightly closable and can be maintained in a low-pressure state.

According to a preferred embodiment of the present invention, the wall is made of metal.

The present invention in another aspect relates to a household appliance,

characterized in that it comprises a storage unit as above recorded.

According to a preferred embodiment of the present invention, the household appliance is a refrigeration appliance having a thermally insulated cabinet, and the storage unit is constructed independently from the cabinet and is received in the cabinet.

According to a preferred embodiment of the present invention, the household appliance is a refrigeration appliance having a thermally insulated cabinet, and the wall is formed by the inner shell of the cabinet.

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 in order to provide further explanation of the present invent, the drawings illustrate preferred embodiments of the present invention, and together with the description are used 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 along the direction A-A in figure 2; Figure 6 is a schematic exploded perspective view of a part of a main body according to a preferred embodiment of the present invention; and

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.

DETAILED DESCRIPTION OF THE INVENTION As shown in figure 1 , a refrigeration appliance 1 comprises a thermally insulated cabinet 2, which cabinet 2 includes an outer shell 2a, an inner shell 2b and a thermal insulation layer 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 have front openings 3a, 4a and 5a respectively, which 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 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 retractable 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 below.

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. 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 to 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 19 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 31 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 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 first securing units respectively.

In the present embodiment, each first 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 first 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 first 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. 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 easily 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.

The manner how the retractable guide unit 14 according to a preferred embodiment of the present invention 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 second securing unit for securing the fixing rail 14a on the box body 11 . In the present embodiment, the second securing unit 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 for securing 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 second securing unit 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.

In the embodiment of the present invention, the guide unit 14 is secured on the low-pressure storage unit 7 by the second securing unit in such a way that the interior of the storing chamber 32 is not in fluid communication with the exterior thereof.

Therefore, any additional sealing measure can be omitted, and the air tightness of the low-pressure storage unit is improved by the guide unit. Furthermore, because the hole is provided at the mounting piece at a distance from the inner wall of the storing chamber but is not provided directly on the wall of the storing chamber, this is more beneficial for the inner wall having a smaller thickness. Therefore, such an

embodiment is more applicable to the case that the wall of the storing chamber is made of metal. It should be understood that, although in the above embodiments the guide unit is constructed independently from the cabinet of the refrigeration appliance and then is secured in the storage unit of the cabinet, the securing measure of the guide unit according to the present invention is obviously also applicable to other cases. For example, the case is that the guide unit is secured between the inner shell of the refrigeration appliance and a storage unit (such as a traditional drawer, a shelf or the like), which storage unit is received in the receiving space defined by the inner shell of the cabinet. Of course, this kind of securing measure is also applicable to other household appliance adopting the guide unit.

Claims

1. A storage unit (7), comprising:

a main body (8) having a receiving space (32);

a storage member (9) movably received in the receiving space (32);

a retractable guide unit (14) connected between the main body (8) and the storage member (9) for guiding the storage member (9) to insert into and retreat from the receiving space (32); and

a securing unit for securing the guide unit (14) to an inner side of a wall (22) of the receiving space (32), wherein the securing unit comprises at least one hole (42) provided in the main body (8) and an insertion member (41 ) passing through and being secured to the hole (42);

characterized in that the securing unit is provided such that the interior of the receiving space (32) is not in fluid communication with the exterior thereof.

2. The storage unit (7) according to claim 1 , characterized in that the hole (42) is a through hole, both ends of the hole are exposed to the receiving space (32), and the hole is entirely inside the receiving space (32).

3. The storage unit (7) according to claim 1 or 2, characterized in that the main body (8) comprises a mounting piece (44) located in the receiving space (32), the mounting piece (44) comprises a mounting portion (45) provided with the hole (42), and a gap is formed between the mounting portion (45) and an inner surface of the wall (22).

4. The storage unit (7) according to claim 3, characterized in that the wall (22) is depressed outwardly at a location corresponding to the mounting portion (45).

5. The storage unit (7) according to claim 3 or 4, characterized in that the mounting piece (44) comprises a connection portion (46) for connecting the wall (22) with the mounting portion (45), and the mounting portion (45) is closer to the storage member (9) than the connection portion (46).

6. The storage unit (7) according to claim 3, 4 or 5, characterized in that the mounting portion (45) is U-shaped.

7. The storage unit (7) according to any one of claims 3 to 6, characterized in that the insertion member (41 ) extends into the gap and is at a distance from the wall (22).

8. The storage unit (7) according to any one of claims 3 to 7, characterized in that the mounting piece (44) is constructed independently from the wall (22) and is then secured to the inner side of the wall (22).

9. The storage unit (7) according to claim 8, characterized in that the mounting piece (44) is welded or bonded to the wall (22).

10. The storage unit (7) according to any one of claims 3 to 7, characterized in that the mounting piece is formed integrally on the wall.

11 . The storage unit (7) according to any one of the preceding claims, characterized in that the securing unit comprises a guide hole (43) provided in the guide unit (14), the insertion member (41 ) is inserted through the guide hole (43) and then extends into the hole (42), and the securing unit secures the guide unit (14) to the main body (8) in a screwed manner.

12. The storage unit (7) according to any one of the preceding claims, characterized in that the receiving space (32) is air-tightly closable and can be maintained in a low-pressure state.

13. The storage unit (7) according to any one of the preceding claims, characterized in that the wall (22) is made of metal.

14. A household appliance, characterized in that it comprises a storage unit (7) according to any one of the preceding claims.

15. The household appliance according to claim 14, characterized in that the household appliance is a refrigeration appliance (1 ) having a thermally insulated cabinet (2), and the storage unit (7) is constructed independently from the cabinet (2) and is received in the cabinet (2).

16. The household appliance according to claim 14, characterized in that the household appliance is a refrigeration appliance having a thermally insulated cabinet, and the wall is formed by an inner shell of the cabinet.