EP2113059B1 - Refrigeration device having a water tank - Google Patents

Abstract

A refrigeration device has a heat-insulated interior (3) and a water tank (13) separated from the interior (3) by an insulating layer. A hollow space (17) is defined on a side of the insulating layer facing the water tank (13). An element (24) is arranged on at least one opening (18; 22, 23) of the insulating layer, said opening connecting the hollow space (17) to the interior (3), and controlls the air exchange via the opening (18; 22, 23). An electric heater (32) can be arranged on the tank (13).

Description

The present invention relates to a refrigerator with a thermally insulated interior and a separate from the interior and from the environment by an insulating layer of water tank according to the preamble of claim 1. Such a refrigeration device is for example from the WO 90/15962 known.

The water in such a tank must never freeze, on the one hand, because the expansion of the water associated with the freezing could destroy the tank, on the other hand, because no water can be tapped from an iced tank. The water tank must therefore not have too close thermal contact with an interior if it can be cooled to temperatures below 0 ° C.

There are known refrigeration appliances, which is trying to meet this requirement by the tank is embedded in a wall of the refrigerator housing, so that it is surrounded both to the outside and to the interior of an insulating layer. The ratio of the thermal conductivities of these layers as well as the indoor and ambient temperatures determine the temperature which the contents of the tank assume under steady state conditions. However, there is the problem that the interior temperature and - to an even greater extent than these - and the ambient temperature are variable. A refrigeration appliance designed for use in temperate latitudes can not satisfactorily cool the tank contents when used in a tropical environment. Conversely, in a refrigerator that supplies satisfactorily cold water in a tropical environment, there is a risk that it will freeze the tank contents in temperate latitudes, especially when used in an unheated room. Such a conventional refrigeration device can therefore not be made uniform for different climates. Manufacturing models that differ in the ratio of insulation layer thicknesses on either side of the water tank requires increased manufacturing effort, and also presents a troublesome constraint to the user when the device he receives is useful only in a limited range of ambient temperatures ,

Furthermore, the need to isolate the water tank against the interior of the refrigerator, to the fact that if after draining of water from the tank fresh water flows from ambient temperature, it takes a long time to cool this fresh water.

Out W02005 / 052477A1 a refrigeration device is known in which such a heater embedded in the wall of the refrigerator water tank is assigned. By preventing the tank from freezing, an insulating layer separating the water tank from the interior can be made substantially thinner than the insulating layer between the interior and the surroundings, so that water flowing into the tank quickly cools. However, the thin insulating layer leads to an increased heat input into the interior. This and the energy required for the heating affect the energy efficiency of the device

Object of the present invention is to provide a refrigeration device that enables energy-efficient operation under highly variable ambient temperatures.

This object is achieved by a refrigeration device with the features of claim 1. Thus, it is possible to choose the strength of the insulating layer between the interior and water tank so that even at low ambient temperatures, a freezing of the tank contents is excluded, if at the same time the air exchange over the Passage through the controlling element is limited to a low value. If, under such conditions, the cooling of the water in the tank is no longer sufficient, the element can be controlled in order to effect an increased exchange of air and thus an increased cooling of the tank. The heater can prevent freezing of the tank even if it is well insulated from the environment.

Another advantage of this refrigerator is that even if the temperature of the water tank is increased due to a recent influx of fresh water, the air exchange with the interior can be increased to cool the fresh water quickly.

The air exchange controlling element may for example be a fan, through the operation of the air exchange is actively promoted. Conceivable, however, is also the Use of a flap or other element modulating the free cross-section of the passage, which in the open state permits air exchange driven in another way, for example by convection, and substantially prevents it in the closed or at least constricted state.

Preferably, the cavity is connected to the interior through a plurality of passages, wherein then at least one of these passages air from the interior into the cavity and through another passage can flow back into the interior. Effective control of the air exchange is also possible if at least one of these passages does not have an air exchange controlling element.

In order not to promote air exchange by convection in the case of different temperatures of the interior and cavity, the several passages expediently at the same height in the interior.

If air exchange between the cavity and the interior is desired, it should be possible to quickly and completely flush hot air out of the cavity. For this purpose, a division is expedient in which the cavity comprises a plurality of each communicating at an upper end with each other chambers.

The passages then each preferably open onto a lower end of the chambers.

To structure the cavity in the communicating chambers ribs may serve, which protrude from a wall of the tank. These ribs simultaneously increase the surface area on which heat exchange between the tank and the air in the cavity is possible and thus accelerate the cooling of the tank contents.

It is also expedient that the cavity and the tank are separated by a housing from the insulating layer. By preventing direct contact between the air in the cavity and the insulating layer, the housing also prevents moisture from the circulating air from precipitating in the insulating layer. Furthermore, the separation of the tank from the insulating layer improves the ease of repair of the device.

The cavity articulated ribs can also protrude from a wall of the housing.

As each passage is directed downwards towards the interior, hot air remains trapped in the cavity, unless the air exchange is driven by external energy, in particular by the fan.

Conveniently, a control circuit is provided which operates the heating when the temperature detected by the temperature sensor falls below a first limit, and which actuates the air exchange controlling element to promote the exchange of air when the detected temperature exceeds a second threshold. The limit values can be in particular +2 or + 10 ° C.

To minimize the risk of leakage of the tank and avoid direct contact of the temperature sensor with the drinking water contained in the tank, the temperature sensor is preferably attached to an outer surface of the tank.

A simple mounting of the temperature sensor with simultaneous close thermal contact with the tank allows a pocket attached to the outer surface of the tank into which the temperature sensor is inserted.

The temperature sensor is preferably located adjacent to a highest point of the tank. Since water is at its highest density at 4 ° C, both the warmest water, when the tank is too warm, and the coldest water, when too cold, are near its highest point, and so can one and the other be detected the same temperature sensor.

Fig. 1

einen schematischen Schnitt durch ein erfindungsgemäßes Kältegerät mit einem in einer Nische der Tür montierten Wassertank;

Fig. 2

einen Schnitt durch ein Gehäuse der Nische entlang einer in Fig. 1 mit II bezeichneten Ebene;

Fig. 3

einen Schnitt entlang der in Fig. 2 mit III bezeichneten Ebene gemäß einer ersten Ausgestaltung der Erfindung;

Fig. 4

eine Ansicht der Vorderseite des Wassertanks;

Fig. 5

eine Abwandlung des Wassertanks von Fig. 4;

Fig. 6

eine perspektivische Ansicht des Wassertank gemäß einer zweiten Ausgestaltung der Erfindung; und

Fig. 7

eine Variante des in Fig. 6 gezeigten Wassertanks.

Further advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying figures. Show it:

Fig. 1

a schematic section through a refrigerator according to the invention with a mounted in a niche of the door water tank;

Fig. 2

a section through a housing of the niche along a in Fig. 1 level denoted by II;

Fig. 3

a cut along in Fig. 2 designated III level according to a first embodiment of the invention;

Fig. 4

a view of the front of the water tank;

Fig. 5

a modification of the water tank of Fig. 4 ;

Fig. 6

a perspective view of the water tank according to a second embodiment of the invention; and

Fig. 7

a variant of in Fig. 6 shown water tanks.

Fig. 1 shows a schematic section through a refrigerator with water tank according to the present invention. The refrigerator shown may be a freezer or the freezer compartment of a side-by-side combination appliance. The walls of the body 1 and door 2, which enclose the interior 3 of the device are realized in a conventional manner in each case with a solid outer skin and inner skin, which enclose a gap filled with insulating synthetic resin. The inner skin 4 of the door 2 is molded in one piece from plastic and has in a central region a projecting into the interior 3 projection 5. The outer skin is composed of a substantially flat front panel 6, which is here shown disguised with a furniture panel 7, and in which a central window is cut, and a substantially cuboid, open at the front, molded plastic injection-molded housing 8, which engages in the projection 5 of the inner skin 4 and the window of the front panel 6 fills. Two steps 9 on the bottom and top wall of the housing 8 divide the niche formed in its interior into an inner region 10 and an outer region 11 which is open toward the front side of the device. The inner region 10 is inserted into the housing 8 from the front , applied to the steps 9 heat-insulating plate 12 is substantially closed. In the inner region 10, a water tank 13 is housed. Lines 14 and 15 connect the water tank 13 on the one hand to the drinking water network and the other with a tapping point 16 in the outer region 11 of the housing 8. Between a rear side of the approximately cuboid water tank 13 and a rear wall of the housing 8 is a cavity 17. Several passages 18, of which in the section of the Fig. 1 only one can be seen connecting the cavity 17 with the interior. 3

In the interior 3 there are an automatic ice maker 19 and a reservoir 20, in which the ice maker 19 outputs finished pieces of ice. A discharge opening of the storage container 20 is located above a shaft 21 which extends through the wall of the door 2 and opens at the ceiling of the outer region 11 1 in the housing 8. Thus, a container placed in the outer region 11 can be filled with both cooled water from the tank 13 and ice pieces from the reservoir 20.

Fig. 2 shows a section through the housing 8 at the level of its inner region 10 along the in Fig. 1 Level II. It can be seen in this section three pipe sockets 22, 22, 23 which are integrally formed on the housing 8 and form walls which delimit the passages 18 of the housing 8 surrounding, not shown in the figure insulating material. The two narrower, each outer pipe socket 22 are empty, as well as in Fig. 3 to recognize who made a cut along the level III Fig. 2 shows. In the middle, further pipe socket 23, a fan 24 is mounted. Of the Fan 24 is used to drive an air flow from the middle pipe socket 23 initially in a limited by two partitions 25 middle chamber 26 of the cavity 17 upwards, divides at its upper end and two outer chambers 27 and the pipe socket 22 down and back to the interior 3 is running.

As in particular in Fig. 3 to see a section through the housing 8 along the line III in Fig. 2 shows the pipe socket 22, 23 at the same height in the interior 3. The opening into the interior 3 openings of the pipe socket 22, 23 are lower than the cavity 17, so that when the fan 24 is turned off, air that is in the cavity 17 is heated, does not drain into the interior space 3.

The cavity 17 is forward or to the right in Fig. 3 bounded by a substantially flat in this embodiment, the rear wall 28 of the water tank 13. On the water tank 13 shown in section, a temperature sensor 29 can be seen, which is inserted into a molded-in at the top of the tank bag 36. The temperature sensor 29 is placed so that it measures the temperature of the water, which is in close proximity to an outlet port 30 of the tank 13, at the upper end of a riser, which in the interior of the tank through a from the top to just above the Bodens extending, in the Fig. 3 Sheath 31 shown in plan view is limited. On the outlet port 30, the line 15 is attached.

On the front wall 42 of the tank 13 is an electric heater, here in the form of a glued foil heater, 32, attached. A signal cable 33 of the temperature sensor 29, a supply cable of the film heater 32 and a supply cable of the fan 24 extend together with the line 15 through a section of the insulating plate 12 to a control circuit, which may be housed, for example, in an operating assembly 34, which in Fig. 1 shown in the outer region 11 of the housing 8 is mounted on the ceiling and carries user-operable buttons 35 for controlling the output of water and / or ice. The control circuit monitors the temperature sensed by the sensor 29 and turns on the fan 24 when the sensed temperature exceeds an upper limit of, for example, 10 °, turns it off again when the temperature reaches a lower, second threshold, for example 6 ° C falls below the heater 42 when falling below a third threshold of, for example, 2 ° C and when exceeding a between the second and the third limit lying fourth limit of for example 4 ° C again. So on the one hand it is ensured that despite possibly variable ambient temperature, the water in the tank 13 reaches a reasonably constant low temperature without freezing, and it is a rapid cooling of fresh water ensures that flows after tapping a larger amount of water in the tank 13.

Fig. 4 shows a perspective view of the tank 13 according to a preferred development of the invention. Notwithstanding an exact cuboid shape, the upper side 37 of the tank is slightly sloping in the width direction, wherein the outlet flange 30 extends from the higher edge of the upper side 37 and an inlet pipe 38 extends from the lower edge. The vertical partition 31 in the interior of the tank 13 is shown as a dashed outline, as well as a plurality of horizontal walls 39, each alternately interlocking emanating from the septum 31 and the side facing away from the viewer side wall of the tank 13. While in a directly adjacent to the inlet port 38 portion 40 of the tank mixing of incoming via the inlet port 38 fresh water with the content of the area 40 is possible, the flow is the tapping of water in the riser and between the horizontal walls 39 laminar. Thus, first a larger amount of cold water can be tapped before mixed, warmer tank contents reaches the outlet port 30.

In the vertical partition wall 31, a small passage opening 41 is formed directly at the upper end thereof, through which air trapped in the region 40 of the tank can rise and reach the outlet connection piece 30. This ensures safe venting of the tank 13.

When no water is tapped, water that cools on the rear wall 28 of the tank flows inside the tank to the bottom thereof. Only when this water is colder than 4 ° C, it tends to rise again, in which case it then penetrates substantially into the riser to the outlet port 30. Therefore, in the case of excessive cooling of the tank 13, the environment of the outlet nozzle 30 is its coldest place, and by the placement of the temperature sensor 29 at this point, the risk of hypothermia can be detected safely. According to the distribution of too cold water in the tank in such a situation, near the ground and in the riser, the Foil heater 32 here has an L-shaped configuration with a riser heating vertical leg and a bottom portion of the tank heated horizontal leg.

Fig. 5 shows a modified embodiment of the tank, in which the inserted into the top of the tank bag 36 is replaced by a laterally arranged pocket 43, which is essentially formed by a along a line 44 to the tank 13 glued or welded elastic film. The film, which is provided with a heat-insulating layer, holds a plate-shaped temperature sensor (not shown) firmly pressed against the side wall of the tank.

Fig. 6 shows a perspective view of the tank 13, seen from the back thereof, according to a second embodiment of the invention. In this embodiment, partitions 45, the cavity 17 as in Fig. 2 illustrated, divided into middle and outer chambers 26, 27, 27, integrally formed on the rear wall 28 of the tank 13. The partitions 45 thus increase the surface area which is available to the tank 13 for heat exchange with air circulating in the cavity 17, thus enabling a faster cooling of the tank contents.

A further development of this idea shows Fig. 7 in which again a perspective view of the tank 13 is shown. The chambers 26, 27, 27, which form the cavity 17, are here designed as recessed into the body of the tank grooves, each bounded by hollow ribs 46. Thus, a particularly rapid heat exchange with tank contents is possible, which is located inside the hollow ribs 46.

Claims (15)

1. Refrigerating appliance with a thermally insulated interior space (3) and a water tank (13) separated from the interior space (3) and the environment by an insulating layer, wherein a cavity (17) is formed at a side of the insulating layer facing the water tank (13) and an element (24) is arranged at at least one passage (18; 22, 23) of the insulating layer, the element connecting the cavity (17) with the interior space (3) and controlling air exchange by way of the passage (18; 22, 23), characterised in that an electric heating means (32) and the cavity (17) are arranged at mutually opposite sides (28, 42) of the tank and that the operation of the element (24), which controls the air exchange, and of the heating means (32) is regulated by at least one temperature sensor (29) arranged at the water tank (13).
2. Refrigerating appliance according to claim 1, characterised in that the element controlling the air exchange is a fan (24).
3. Refrigerating appliance according to one of the preceding claims, characterised in that the cavity (17) is connected with the interior space (3) by a plurality of passages (18; 22, 23), wherein at least one of the passages (22) does not have an element controlling the air exchange.
4. Refrigerating appliance according to claim 3, characterised in that the several passages (18; 22, 23) open into the interior space (3) at the same height.
5. Refrigerating appliance according to claim 3 or 4, characterised in that the cavity (17) comprises a plurality of chambers (26, 27) respectively communicating with one another at an upper end.
6. Refrigerating appliance according to claim 5, characterised in that the passages (18; 22, 23) respectively open at a lower end of the chambers (26, 27).
7. Refrigerating appliance according to claim 5 or 6, characterised in that the cavity (17) is divided into the communicating chambers (26, 27) by ribs (45, 46) protruding from a wall of the tank (13).
8. Refrigerating appliance according to any one of claims 1 to 7, characterised in that the cavity (17) and the tank (13) are separated by a housing (8) from the insulating layer.
9. Refrigerating appliance according to claim 5 or 6 and claim 8, characterised in that the cavity (17) is divided into the communicating chambers (26, 27) by ribs (25) protruding from a wall of the housing (8).
10. Refrigerating appliance according to any one of the preceding claims, characterised in that each passage (18) is oriented downwardly towards the interior space (3).
11. Refrigerating appliance according to any one of the preceding claims, characterised in that a respective temperature sensor (29) is provided at the water tank (13) at its upper region and lower region in the installed position.
12. Refrigerating appliance according to any one of the preceding claims, characterised by a regulating circuit for operating the heating means (32) when the temperature detected by the temperature sensor (29) falls below a first limit value and for actuating the element (24), which controls the air exchange, in order to promote air exchange with the interior space (3) when the detected temperature exceeds a second limit value.
13. Refrigerating appliance according to any one of the preceding claims, characterised in that the at least one temperature sensor (29) is fastened to an outer surface of the tank (13).
14. Refrigerating appliance according to claim 13, characterised in that the at least one temperature sensor is plugged into a pocket (36, 43) mounted at the outer surface of the tank.
15. Refrigerating appliance according to any one of the preceding claims, characterised in that the at least one temperature sensor (29) is arranged adjacent to a highest point of the tank (13).

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