Frost-free Refrigeration Appliance

Abstract

A refrigeration appliance, particularly a domestic refrigeration appliance, has a thermally-insulating housing in which at least one first and one second inner chamber are separated from one another by a thermally-insulated wall. The first inner chamber is divided into a storage compartment and an evaporator chamber. A passage in the thermally-insulated wall connects the evaporator chamber to the second inner chamber. At least one closure element for controlling the air exchange is housed, in the passage, between the evaporator chamber and the second inner chamber.

Description

[0001] The present invention relates to a refrigeration appliance, particularly a domestic refrigeration appliance, in which at least one first and one second inner chamber are separated from one another by a thermally-insulating wall, in a thermally-insulating housing, in order to form compartments for the storage of refrigerated goods at different temperatures, and in which the first inner chamber is divided into a storage compartment for the refrigerated goods and an evaporator chamber, and a passage in the thermally-insulating wall connects the evaporator chamber to the second inner chamber in order to permit a cooling of the second inner chamber without this requiring a separate evaporator.

[0002] Generally, in such a refrigeration appliance the second inner chamber is also divided into a storage compartment for refrigerated goods and an air channel, the passage opening therein and the cold air being distributed therefrom in the storage compartment of the second inner chamber via a plurality of openings of an air channel cover.

[0003] In order to be able to control the distribution of cold air to the two storage compartments, a closure element is required, it being possible thereby to cut off one of the storage compartments from the cold air supply or to throttle at least significantly the inflow of cold air to the relevant storage compartment.

[0004] In a conventional refrigeration appliance, such a closure element comprises a flap which is arranged in a lower region of the air channel of the second inner chamber. With this construction, a lower part of the air channel below the closure element is continuously connected to the evaporator chamber and, therefore, may reach temperatures which may be considerably below the desired temperature of the storage compartment of the second inner chamber. When this storage compartment, for example, is a normal refrigeration compartment but the evaporator is also designed at the same time to be able to cool a freezer compartment, this lower region of the air channel may then be cooled to considerably below 0.degree. C. and lead to frost damage to refrigerated goods in the storage compartment of the second inner chamber. In order to eliminate this, firstly it is necessary to configure the air channel cover to be thermally-insulating, wherein the space required for a thermally-insulating layer at this point is lost from the usable volume of the second inner chamber, and secondly a reliable seal between the air channel and the storage compartment of the second inner chamber is necessary in order to prevent an undesirable escape of cold air into the storage compartment past the closure element, which makes the installation of the air channel cover complex and costly.

[0005] It is the object of the present invention to provide a refrigeration appliance of the type mentioned in the introduction which is able to be mounted in a simple and cost-effective manner and which has a large usable volume with the given external dimensions.

[0006] The object is achieved, in a refrigeration appliance in which at least one first and one second inner chamber are separated from one another by a thermally-insulating wall, in a thermally-insulating housing, and the first inner chamber is divided into a storage compartment and an evaporator chamber and a passage in the thermally-insulating wall connects the evaporator chamber to the second inner chamber, by at least one closure element for controlling the air exchange being housed, in said passage, between the evaporator chamber and the second inner chamber.

[0007] This construction ensures that a boundary between the temperature zones of the first and the second inner chamber extends exactly inside the thermally-insulating wall. As a result, the need to provide further costly thermal insulation inside one of the inner chambers is dispensed with, and the spaced saved thereby benefits the usable volume. Since only low temperature gradients are present on those parts which are installed in one of the two inner chambers, however, a costly seal is no longer necessary on said parts in order to prevent an undesired flow of heat, and if a seal is desired it is able to be implemented accurately.

[0008] The closure element may comprise a flap which is rotatable between an open position and a closed position about an axis.

[0009] In order to facilitate the installation and for an effective sealing action of the flap in the closed position, it is advantageous if the closure element also comprises a frame which completely surrounds the flap in its closed position. This frame may function as a sealing frame.

[0010] In this case, the second inner chamber is also preferably divided by an air channel cover into a storage compartment and at least one air channel in order to facilitate a uniform distribution of the supplied cold air in the entire storage compartment.

[0011] Preferably, two parallel air channels are provided, one thereof extending from the passage into a lower region of the second inner chamber and the other thereof extending from the passage past the lower region into an upper region of the second inner chamber.

[0012] In order to be able to control a temperature gradient between the upper and the lower region of the second inner chamber, and thus, for example, to be able to use a region of the storage compartment thereof as a normal refrigeration compartment and a further region thereof as a fresh food refrigeration compartment, a closure element is preferably assigned to each air channel. In this case, a single closure element may be assigned to each air channel but also a single closure element may control a plurality of air channels.

[0013] For facilitating the assembly, the closure element and/or the closure elements are preferably combined with a motor which drives said elements to form a sub-assembly which is mounted in the passage between the inner chambers. In this case, a single motor may be assigned to both closure elements and connected to the closure elements via a gear mechanism, for example by means of two eccentric cams which are arranged in order to initiate phase-shifted movements of the closure elements, so that at least a position of the motor in which both closure elements are closed, a position in which the first closure element is open and the second closure element is closed, and a position in which the first closure element is closed and the second closure element is open, and possibly a position in which both closure elements are open, are present.

[0014] One and the same closure element may also block the passage between the first and the second inner chamber in a first position, connect the first inner chamber to a first air channel of the second inner chamber in a second position and connect the first inner chamber to a second air channel of the second inner chamber in a third position.

[0015] If the first inner chamber and the second inner chamber in each case are defined by an internal container--typically deep-drawn from a flat plastics material--a tubular housing may be provided in the passage between said inner chambers, said housing extending between opposing apertures of the internal containers through a thermally-insulating layer of the wall.

[0016] The housing preferably comprises two flanges which in each case bear against one of the two internal containers. The flanges may bear against the sides of the internal containers facing the inner chambers, so that the internal containers are pressed against the flanges, when the wall between said internal containers is foamed; preferably the flanges bear on the foam side against the internal container.

[0017] In order to permit the production of the housing using simple tools, the housing may be made up of two housing parts, each thereof comprising one of the flanges.

[0018] A foamed part, for example a molded part made of expanded polystyrene, may be arranged between a rear face of the air channel and a rear wall of the internal container of the second inner chamber. Since such a foamed part contributes to the thermal insulation of the second inner chamber, the thickness of the thermally-insulating layer outside the internal container on the rear wall thereof may be correspondingly reduced and/or the depth of the internal container may be increased. This in turn permits the aperture of the second inner chamber, where the passage opens into the first inner chamber, to be positioned outside a rounded transition between the bottom and the rear wall of the internal container, whereby the aperture is able to be molded more easily, without usable volume in the second inner chamber being lost thereby.

[0019] The air channel cover may come into contact with the foamed part on both sides of the air channel, so that said foamed part is fixed between the air channel cover and the rear wall.

[0020] The closure element should be able to be inserted through one of the apertures of the two internal containers into the housing. At its simplest, the mounting of the closure element is generally via the upper aperture.

[0021] A clamp which secures the closure element in its installed position may be latched to the walls of the passage between the closure element and the inner chamber, the closure element being inserted from said inner chamber.

[0022] If the closure element and the motor which drives said closure element are combined to form a sub-assembly, then the clamp is preferably arranged so as to be placed across the motor, since whilst the clamp is able to secure the sub-assembly effectively at that point, at the same time it does not obstruct an air flow passing the closure element.

[0023] Further features and advantages of the invention are disclosed from the following description of exemplary embodiments with reference to the accompanying figures, in which:

[0024] FIG. 1 shows a schematic section in the vertical direction through the body of a refrigeration appliance according to the invention;

[0025] FIG. 2 shows a section in the horizontal direction along the plane II-II of FIG. 1;

[0026] FIG. 3 shows an exploded view of a housing which is arranged in a passage between the compartments of the refrigeration appliance body of FIG. 1 and a sub-assembly to be mounted in the housing;

[0027] FIG. 4 shows a schematic section through the housing and the sub-assembly in the state mounted in the body of the refrigeration appliance; and

[0028] FIG. 5 shows a simplified modification of the housing and the sub-assembly.

[0029] FIG. 1 shows a schematic vertical section through the body of a no-frost refrigeration appliance according to the invention. Two inner chambers 2, 3 are formed in the body 1, one 2 in the upper part of the body and the other 3 in the lower part of the body 1. In a manner known per se, the inner chambers 2, 3 are defined in each case by an internal container 4 and/or 5 which is deep-drawn from flat plastics material. Both internal containers may be deep-drawn in one piece from the same blank; in the case shown in the figure, the internal containers 4, 5 are produced separately and encased in profiles of a frame 6 on the front face of the body 1. An intermediate space between the outer faces of the internal containers 4, 5 and an outer skin of the body 1, not shown in FIG. 1, is filled with an insulating material layer 7 which is obtained by injection-molding and expanding a foam-forming synthetic resin in the intermediate space. The insulating material layer 7 extends in this case in one piece into a wall 8 between the inner chambers 2, 3.

[0030] The inner chamber 3 is sub-divided by a partition 10 substantially parallel to the rear wall 9 of its internal container 5 into a storage compartment for refrigerated goods, in this case a freezer compartment 11 and an evaporator chamber 12. A further wall 13 divides the evaporator chamber 12 into a suction region 14 in which a lamella-type evaporator 15 is also located and a distributer region 16. A fan 17 is arranged in an opening of the wall 13 in order to suction air through the evaporator 15 and to pump the air thus cooled into the distributor region 16. Via distributor openings 18 in the wall 13, a portion of the cooled air passes directly back into the storage chamber 11. The remaining air passes via a passage 19 in the wall 8 into an air channel 20 of the upper inner chamber 2.

[0031] The air channel 20 is defined toward a rear wall 23 of the internal container 4 by a molded part 24 made of expanded polystyrene (EPS) and delimited from a storage compartment 21 by a plate-shaped air channel cover 22. The air channel cover 22, and the wall 13, are provided with distributor openings 18, via which the cold air distributed vertically is able to escape into the storage compartment 21.

[0032] The air channel 20 and the air channel cover 22 may extend over the entire height of the inner chamber 2; in the design shown here they extend only from the bottom 25 of the inner chamber 2 to a horizontal partition 26 inserted in the internal container 4, so that the air guided in the air channel 20 is only able to be distributed in a lower region 27 of the storage compartment 21. In order to supply a region 28 above the partition 26, a second air channel 29 is guided through the molded part 24 partially outside the cutting plane of FIG. 1 and the air circulating in this air channel 29 is distributed in the upper region 28 of the inner chamber 2 via distributor openings 18 of a further air channel cover 30.

[0033] FIG. 2 shows a section through the lower region of the normal refrigeration compartment 2, level with the line II-II of FIG. 1. The cutting plane of FIG. 1 is denoted in FIG. 2 by I-I. The air channel 20 in this case is defined at the front by the air channel cover 22 and toward the rear wall 23 and, in the lateral direction through the molded part 24, the air channel cover 22 bears against the molded part 24 on both sides of the air channel 20.

[0034] Latching connections are provided in order to fix the air channel cover 22 in the position shown and to hold the molded part 24 clamped between the air channel cover 22 and the rear wall 23. Here, the latching connections in each case comprise a sleeve 31 and a latching pin 32 engaging in the sleeve. The sleeve 31 is bonded, welded or fastened in another suitable manner to the rear wall 23 and engages in a passage 33 of the molded part 24. The latching pin 32 has a shank 34 with a plurality of frusto-conical segments which, when inserted into the sleeve 31, which is slotted in the longitudinal direction, widen said sleeve in a resilient manner until the segments come into engagement with complementary latching contours in the interior of the sleeve 31. Each latching pin 32 is inserted sufficiently deeply into its sleeve 31 until a head 35 of the latching pin 32 bears fixedly against the air channel cover 22.

[0035] In each case at both ends of the passage 19 apertures 37 (see FIG. 1) are cut into the bottom 25 of the internal container 4 and the top 36 of the internal container 5. A housing 38 which extends between the apertures 37 through the wall 8, in order to prevent the passage 19 from being closed when the insulating material is foamed, is shown in FIG. 3 in a detailed perspective view. The housing 38 comprises a lower housing part 39 and an upper housing part 40 which are injection-molded from plastics separately from one another and plugged together before inserting into the wall 8.

[0036] The lower housing part 39 in this case comprises two pipe connectors 41, 42 which are slightly widened in the upward direction and are respectively of rectangular cross section and a flange 43 extending around the lower ends of the pipe connectors 41, 42, said flange being provided in order to bear against the top 36, all around the aperture 37 thereof, when the housing 38 is inserted from the rear face of the body 1 into the wall 8. On its lower face, not visible in FIG. 3, the flange 43 may be provided with flat ribs which engage in the aperture 37 of the top 36 along the edges thereof in order to fix the installed position of the housing 38 in an accurate manner.

[0037] In the upper housing part 40 a flange 44 surrounds an individual connector 45 which is also rectangular in cross section and which at its lower end branches into two connecting parts 46, 47 complementary to the pipe connectors 41, 42. On the narrow sides of the flange two projections 67 are formed which together with the flange form grooves which are open in the lateral direction. The aperture 37 of the bottom 25 at its edge facing the rear wall 9 has two widenings 68 (see FIG. 4), the projections 67 passing through said widenings when inserting the housing 38 into the wall 8, so that in the mounted state they bear against the bottom 25 and clamp the housing 38 to the bottom 25.

[0038] When the body 1 is foamed, retaining tools are inserted into the inner chambers 2, 3, said tools forcing the bottom 25 and the top 36 sufficiently far apart until both bear against the flanges 44, 43 in a foam-tight manner.

[0039] In each case a latching projection 49 is positioned on the narrow sides 48 of the connector 45 such that when the downwardly tapering connecting parts 46, 47 engage by a frictional connection in the pipe connectors 41, 42, resilient latching hooks 50 of the lower housing part 39 engage behind the latching projections 49.

[0040] A sub-assembly 51 shown in FIG. 3 above the upper housing part 40 comprises a motor housing 52 in the form of a vertically oriented cuboid, rectangular frames 53, 54 protruding from the two main surfaces thereof in plan view. The sub-assembly 51 is provided in order to be inserted, in the orientation shown, from above into the upper housing part 40; in the installed position the motor housing 52 divides the interior of the connector 45 into two parts, one thereof extending in the extension of the connecting part 46 and the other thereof extending in the extension of the connecting part 47, and the frames 53, 54 are positioned on a shoulder 55 extending on at least one longitudinal wall of the connector 45.

[0041] In each frame 53, 54 a flap 56 (see FIG. 4) is pivotably mounted about an axis 57. In its closed position the walls of the flap 56 bear tightly against the frame 53 and/or 54 so that each flap 56 is able to block one of the two passages on both sides of the motor housing 52. From this closed position shown as an outline in dashed lines in FIG. 4, each flap 56 is pivotable downwardly into the connector 45 until it reaches an open position illustrated in solid lines in FIG. 4, in which it does not prevent an air flow from the evaporator chamber 12 to one of the air channels 20 and/or 29.

[0042] In addition to an electric motor, a gear mechanism is also accommodated in the motor housing 52, said gear mechanism making it possible to control the positions of the flaps 56 independently of one another by means of two eccentric cams, as mentioned above, for example. When refrigeration is not required in the normal refrigeration compartment 2, both flaps 56 are closed, when refrigeration is only required in the lower region 27 only the flap 56 of the frame 53 is open in order to subject only the air channel 20 to cold air, when refrigeration is required in the upper region 28 only the flap 56 of the frame 54 is open and when refrigeration is required at the same time in both regions 27, 28 both flaps 56 may be open at the same time.

[0043] Since the upper region 28 and the lower region 27 of the upper storage compartment 21 are thus selectively able to be subjected to cold air, different temperatures may be set in both regions. The temperature of the lower region 27 should be the lower temperature, not least because at the height of the lower region 27 the molded part 24 is thicker and thus the thermal insulation of the lower region 27 is more effective than that of the upper region. Thus, in particular, the upper region 28 may be used as a normal refrigeration compartment and the lower region may be used as a fresh food refrigeration compartment.

[0044] In a simpler design of the refrigeration appliance, in which the storage compartment 21 is not sub-divided and only one individual air channel is provided behind the cover 30, one of the frames 53, 54, the flap mounted therein and optionally the eccentric cam driving the flap may be dispensed with.

[0045] A clamp 58 is also provided in order to fix the sub-assembly 51 in the connector 45, said clamp in the mounted state extending over the upper face of the motor housing 52 from one longitudinal wall of the connector 45 to the other. The clamp 58 has an upper wall 59 and two side walls 60 which encompass the motor housing 52 on both sides. In the mounted state, the clamp 58, on the one hand, is fixed by engagement in a recess 61 to a rear longitudinal wall of the connector 45 and, on the other hand, is fixed by latching between two latching hooks 62 to a front edge of the flange 44. On the clamp 58, as shown in FIG. 3, a hook 63 may be provided, a supply cable 64 of the motor being able to be secured below said hook in order to ensure that it does not hang into one of the frames 53, 54 and prevent the movement of the flaps 56.

[0046] FIG. 5 shows a simplified variant of the housing 37 and the sub-assembly 51 in a schematic section. The sub-assembly 51 in this case comprises a motor located outside the cutting plane and a single flap 56, of a butterfly shape, which is rotatable about an axis 57 perpendicular to the cutting plane. The sub-assembly is fixed by a clamp 58 extending perpendicular to the cutting plane, acting on front walls of the upper housing part 40, and which divides the opening of the upper housing part 40 into a front part 65 communicating with the air channel 20 and a rear part 66 communicating with the air channel 29. In the position of the flap 56 shown in solid lines, only the air channel 20 is subjected to cold air; after a rotation of the flap 56 clockwise by ca. 30.degree., into the position shown in dashed lines, the cold air is distributed to both air channels 20, 29; after a further rotation by ca. 30.degree., only the air channel 29 is supplied, and after a further rotation by ca. 60.degree. both air channels 20, 29 are blocked. All of the positions are accessible during a continuous rotation, without the rotational direction of the motor having to be altered.

LIST OF REFERENCE NUMERALS

[0047] 1 Body [0048] 2 Inner chamber [0049] 3 Inner chamber [0050] 4 Internal container [0051] 5 Internal container [0052] 6 Frame [0053] 7 Insulating material layer [0054] 8 Wall [0055] 9 Rear wall [0056] 10 Partition [0057] 11 Freezer compartment [0058] 12 Evaporator chamber [0059] 13 Wall [0060] 14 Suction region [0061] 15 Lamella-type evaporator [0062] 16 Distributor region [0063] 17 Fan [0064] 18 Distributor opening [0065] 19 Passage [0066] 20 Air channel [0067] 21 Storage compartment [0068] 22 Air channel cover [0069] 23 Rear wall [0070] 24 Molded part [0071] 25 Bottom [0072] 26 Intermediate wall [0073] 27 Lower region [0074] 28 Upper region [0075] 29 Air channel [0076] 30 Air channel cover [0077] 31 Sleeve [0078] 32 Latching pin [0079] 33 Passage [0080] 34 Shank [0081] 35 Head [0082] 36 Top [0083] 37 Aperture [0084] 38 Housing [0085] 39 Lower housing part [0086] 40 Upper housing part [0087] 41 Pipe connector [0088] 42 Pipe connector [0089] 43 Flange [0090] 44 Flange [0091] 45 Connector [0092] 46 Connecting part [0093] 47 Connecting part [0094] 48 Narrow side [0095] 49 Latching projection [0096] 50 Latching hook [0097] 51 Sub-assembly [0098] 52 Motor housing [0099] 53 Frame [0100] 54 Frame [0101] 55 Shoulder [0102] 56 Flap [0103] 57 Axis [0104] 58 Clamp [0105] 59 Upper wall [0106] 60 Side wall [0107] 61 Recess [0108] 62 Latching hook [0109] 63 Hook [0110] 64 Supply cable [0111] 65 Front part [0112] 66 Rear part [0113] 67 Projection [0114] 68 Widening

Claims

1-15. (canceled)

16. A refrigeration appliance, comprising: a thermally-insulated housing; a thermally-insulated wall having a passage formed therein; at least one first and one second inner chamber being separated from one another by said thermally-insulated wall in said thermally-insulated housing, said first inner chamber is divided into a storage compartment and an evaporator chamber and said passage in said thermally-insulated wall connecting said evaporator chamber to said second inner chamber; and at least one closure element for controlling an air exchange is housed, in said passage, between said evaporator chamber and said second inner chamber.

17. The refrigeration appliance according to claim 16, wherein said closure element has a flap.

18. The refrigeration appliance according to claim 17, wherein said closure element has a frame which completely surrounds said flap in a closed position.

19. The refrigeration appliance according to claim 16, further comprising an air channel cover, said second inner chamber is divided by said air channel cover into a further storage compartment and at least one air channel.

20. The refrigeration appliance according to claim 19, wherein said at least one air channel is one of two air channels, a first of said air channels extends from said passage into a lower region of said second inner chamber and a second of said air channels extending from said passage past said lower region into an upper region of said second inner chamber.

21. The refrigeration appliance according to claim 20, wherein said at least one closure element is assigned to each of said air channels.

22. The refrigeration appliance according to claim 21, further comprising a motor for driving said at least one closure element, said at least one closure element combined with said motor forms a sub-assembly which is mounted in said passage.

23. The refrigeration appliance according to claim 19, wherein said thermally-insulated wall has a thermally insulating layer; wherein said first inner chamber and said second inner chamber in each case are defined by an internal container each having an aperture formed therein; and further comprising a tubular housing and in said passage said tubular housing extends between said apertures of said internal containers through said thermally insulating layer of said thermally-insulated wall.

24. The refrigeration appliance according to claim 23, wherein said tubular housing has two flanges which in each case bear against said internal container of one of said first and said second inner chamber.

25. The refrigeration appliance according to claim 24, wherein said tubular housing has two plug-connected housing parts each with one of said two flanges.

26. The refrigeration appliance according to claim 23, further comprising a foamed part disposed between a rear face of said air channel and a rear wall of said internal container of said second inner chamber.

27. The refrigeration appliance according to claim 26, wherein said air channel cover comes into contact with said foamed part on both sides of said air channel and said foamed part is fixed in position between said air channel cover and said rear wall.

28. The refrigeration appliance according to claim 16, wherein said closure element is able to be inserted from sides of one of said first and said second inner chamber into said passage.

29. The refrigeration appliance according to claim 28, further comprising a clamp, said closure element is secured by said clamp which is latched to said thermally-insulated wall between said closure element and said second inner chamber, said closure element being inserted from said second inner chamber.

30. The refrigeration appliance according to claim 22, further comprising a clamp disposed so as to be positioned across said motor.

31. The refrigeration appliance according to claim 16, wherein the refrigeration appliance is a domestic refrigeration appliance.