RU2690292C2 - Refrigerating and / or freezing device - Google Patents

Abstract

FIELD: cooling.SUBSTANCE: invention relates to cooling and / or freezing device. It comprises cooled internal space and thermoelectric element, in particular, Peltier element, which is located so that inner space is cooled with the help of thermoelectric element. Thermoelectric element is connected to the corresponding heat exchanger by means of conducting heat both on the cold side directed to the inner space and on the outward directed to the warm side. In the zone of the upper side of that heat exchanger, which is connected to the cold side of the thermoelectric element, a condensation surface is formed, having a lower temperature compared to the adjacent surface of the inner space. Condensation zone is formed around the condensation surface and thereon. Provided is a drain element for condensate, which leads from the condensation zone to the evaporation zone, which is formed by the evaporation cup, contacting the heat conducting way with the heat exchanger, which is connected to the thermoelectric element warm side.EFFECT: reduced power consumption.6 cl, 2 dwg

Description

This invention relates to a refrigerating and / or freezing device comprising at least one cooled internal space and at least one thermoelectric element, in particular, at least one Peltier element, which is located so that the internal space is cooled with a thermoelectric element.

When opening refrigerating and / or freezing devices warm air enters the cooled internal space. Due to the cooling of the air, the saturated vapor pressure is reduced, which leads to condensation of moisture from the air on the cold surfaces of the cooled internal space.

In refrigeration and / or freezing devices known from the prior art, condensate is collected by performing a refrigeration system and through a discharge chute or the like. heading out. There he gathers in a bowl for condensate, which may be above the compressor. Based on the compressor waste heat, the water in the bowl evaporates.

In the thermoelectric refrigeration and / or freezer, for efficiency reasons, it is advisable to keep the temperature difference at the heat pump much smaller than in the compressor refrigerating machine. This leads to the fact that in the cooled internal space there is no significantly cooler wall on which condensation occurs, and that there is no place outside on the device with a locally elevated temperature that can be used to evaporate the condensate.

The basis of this invention is to further improve the refrigeration and / or freezing device of the initially mentioned type, so that a reliable evaporation of the condensate discharged from the cooled internal space occurs.

This problem is solved using a refrigeration and / or freezer with signs of paragraph 1 of the claims. In line with this, there are means for evaporation of condensate, which have a heat exchanger located outside the cooled inner space. The term heat exchanger is understood to mean any element that has a temperature that is sufficient to evaporate the condensate.

In one embodiment of the invention, it is provided that the heat exchanger is formed by the warm side of a thermoelectric element or by means of an element that is in heat-conducting connection with the warm side of the thermoelectric element with the possibility of heat transfer, in particular, heat conductivity. This thermoelectric element can be simultaneously located so that it cools the internal space of the device with its cold side.

Such a system can work stationary with the help of a control or adjustment unit, i.e. The thermoelectric element works with a constant power or, respectively, with a power that is required to maintain a constant temperature in a cooled internal space and is in each case independent of the resulting condensate.

For this, it is possible that on the surface in the cooled internal space of the device, on which, based on the arrangement of thermoelectric cooling, the lowest temperature, is provided a device for collecting and draining condensate. He is removed from the device and enters the team bowl, which, for example, is located around the zone of the outer shell, in which there is a high temperature.

These measures may be sufficient for moderate climatic conditions.

For conditions or, respectively, regions with a particularly high air humidity, the amount of moisture produced can be so large that, on the one hand, on the basis of a small temperature difference, i.e. a small temperature gradient in the inner space, condensation no longer occurs locally at the coldest point. Another problem is that the temperature in the evaporation zone is not high enough to evaporate all the condensate.

To counteract this, in another embodiment of the invention, it is provided that there is a control or, accordingly, an adjusting unit for performing one or several condensation cycles. This unit is designed so that it during the condensation cycle increases the temperature difference for the purpose of condensation and / or evaporation.

This means that during a condensation cycle, the power of, for example, a thermoelectric element increases so that its temperature in the cooled internal space decreases compared to normal operation, where there is no condensation cycle, and / or that the temperature of the thermoelectric element on the outside of the device rises compared to normal operation where there is no condensation cycle.

The condensation cycle can be carried out with certain, possibly regular time intervals or depending on one or several parameters. One such parameter is, for example, air humidity and / or the amount of condensate formed. These parameters can be supplied to the control or adjustment unit, which then, depending on them, initiates a condensation cycle or ensures further operation of the device in normal mode.

It is possible that means are provided by which it is possible to determine whether condensate is present, and that a control or adjustment unit connected to these means can be designed so that the capacity of the means for evaporation of the condensate increases and / or the temperature is at least in one place in the cooled internal space decreases, when existence of condensate is defined.

For concentration of condensate in one or several places, it can be provided that there is at least one condensation surface in the cooled internal space, the temperature of which lies below the temperature of other surfaces in the cooled internal space, so that condensate forms on the condensation surface.

The condensation surface can be formed using at least one thermoelectric element. In this case, it can be a thermoelectric element, which is already used to cool the cooled internal space, or else a thermoelectric element used only to form condensate.

The thermoelectric element used only for the formation of condensate can be located so that it releases its waste heat into the cooled internal space. Thus, the element can work very efficiently and can operate with minimal power. Due to this additional thermoelectric element, the creation of cold and the formation of condensate are effectively decoupled, so that when choosing the geometrical parameters of condensation, the frame conditions for the creation of cold should not be taken into account.

It is possible that there is a means for determining the opening of the closing element of the device, and that the control or adjusting unit for cyclic cooling is designed so that it works depending on the detected opening. Thus, according to one embodiment of the invention, the condensation cycle is always initiated after the door is opened, i.e. when the door or other closing element closes again, in order to direct warm air again above the condensation point.

To support the deposition of moisture on the condensation surface, it may be advisable to have a fan that is located so that it mixes the air in the cooled inner space.

Alternatively, or in addition, at least one fan may be provided in the evaporation zone in order to increase the evaporation rate.

At least one waste element may be provided by which the condensate is supplied to the evaporation means, while it is preferably provided that the waste element is of such a size that the condensate is supplied by capillary forces.

In the simplest case, the waste element is located so that the condensate under the action of gravity simply flows down from the cooled internal space.

If evaporation at other points is desired, such as, for example, the lid of the device, it can be provided that the condensate that is generated is directed to a specific point or zone of evaporation using capillary forces, such as, for example, the lid of the device.

In the refrigerator and / or freezer according to the invention between the outer shell, i.e. the outer side of the housing, and the inner wall that restricts the inner space to be cooled, and / or between the inner and outer side of the door or other closure element, is preferably complete vacuum insulation. The vacuum insulation body may be located between the outside of the housing in the inner vessel and / or between the outside and the inside of the door or other closure member.

Thus, in one preferred embodiment of the refrigeration and / or freezer according to the invention, it is partially or completely isolated using a full vacuum system. Here we are talking about a system in which the insulation between the outer side and the inner space on the housing and / or on the closing element consists solely or predominantly of the evacuated element, in particular, in the form of a shell of a vacuum-tight film or, respectively, of a high-barrier film, with an auxiliary material. Preferably, the complete vacuum insulation is formed using one or more vacuum-insulated bodies, which have said film, a zone surrounded by a film, and an auxiliary material contained therein. Additional thermal insulation using insulating foaming and / or vacuum-insulated panels or using other means of thermal insulation between the inside and the outside of the device is preferably not provided.

This preferred type of thermal insulation in the form of a full vacuum system can pass between the inner wall and the outer shell of the housing and / or between the inner side and the outer side of the closing element, such as, for example, a door, flap, cover or the like.

A full vacuum system can be obtained so that the shell of a gas-tight film is filled with auxiliary material, and then vacuum-tightly closed. In one embodiment, both the filling and the vacuum-tight closure of the shell are carried out at normal or ambient pressure, respectively. In this case, the evacuation takes place by connecting a suitable, encased interface, for example, an evacuation pipe, which the valve may have, with a vacuum pump. Preferably, during evacuation, there is normal or, respectively, ambient pressure outside the shell. In this embodiment, preferably at no point in time of manufacture does not require placement of the shell in a vacuum chamber. Therefore, in one embodiment, during the manufacture of vacuum insulation, the vacuum chamber can be dispensed with.

Preferably, the shell contains a high-barrier film or is a high-barrier film that vacuum-closes the vacuum zone formed by the shell.

By vacuum-tight or impermeable to diffusion, respectively, by vacuum-tight or impermeable to diffusion, by a compound, respectively, by a high-barrier film, preferably means a shell or, respectively, a compound or, accordingly, a film, by means of which the gas inlet in a vacuum-isolated body is reduced so much thermal conductivity of a vacuum-insulated body due to gas intake is rather small during its service life. Under the service life is taken a period of time, for example, 15 years, preferably 20 years and particularly preferably 30 years. Preferably, the increase in thermal conductivity of the vacuum-insulated body due to the gas inlet during its service life is less than 100% and particularly preferably less than 50%.

Preferably, the specific relative to the surface gas transmission rate of the shell or, respectively, the compound or, respectively, high-barrier film is less than 10 ^-5 mbar l / s m ² , particularly preferably less than 10 ^-6 mbar l / s m ² (measured in accordance with ASTM D-3985). This gas permeation rate is valid for nitrogen and oxygen. For other gases (in particular, water vapor), the gas penetration rates are also low, preferably in the range of less than 10 ^-2 mbar l / s m ² and particularly preferably in the range of less than 10 ^-3 mbar l / s m ² (when measured according to with standard ASTM F-1249-90). Preferably, due to these low gas penetration rates, the above increases in thermal conductivity are achieved.

The shell system known from the field of vacuum panels is the so-called high-barrier films. In the context of the present invention, this means preferably single-layer and multilayer films (which are preferably heat-sealable) with one or more barrier layers (usually metal layers or oxide layers, while aluminum or, respectively, aluminum oxide is preferably used as a metal or oxide) which meet the above requirements (increase of thermal conductivity and / or specific relative to the surface of the gas penetration rate) as a barrier against n oniknoveniya gas.

The above values or, respectively, the specified implementation of high-barrier film, are given as an example of data that does not limit the invention.

The idea of installing a thermoelectric element in a cooled internal space to thereby form a condensation surface is not limited to thermoelectric devices. Thus, the invention additionally relates to any refrigerating and / or freezing device with a cooled internal space and with a thermoelectric element installed therein, wherein a control or adjustment unit is provided that controls the thermoelectric element so that it forms a condensation surface. The condensation surface is preferably colder than the neighboring surfaces or the coldest surface in the cooled inner space.

In one embodiment, it is provided that the refrigeration and / or freezer is a household appliance or a commercial refrigerator. For example, this includes devices for a fixed location in a household, in a hotel room, in a commercial kitchen, or in a bar. For example, it may be a refrigerator for wine. In addition, the invention relates to refrigerated and / or freezer cabinets. Devices according to the invention can take place mates for connecting to an electrical network, in particular, with an electrical network for domestic needs (for example, a plug) and accessories for installation, for example, staged legs or a mating point for fixing inside a furniture niche. For example, the device may be an embedded device or a floor device.

In one embodiment, the vessel or device is designed so that it can operate with an alternating voltage, such as, for example, a household voltage, for example, 120 V with a frequency of 60 Hz or 230 V and with a frequency of 50 Hz. In an alternative embodiment, the vessel or device can operate with a constant current with a voltage of, for example, 5 V, 12 V or 24 V. In this embodiment, it can be provided that a plug-in power supply unit is provided inside or outside the device, through which the device is supplied electricity. The advantage of using thermoelectric heat pumps in this embodiment is that all electromagnetic compatibility problems arise only in the power supply.

In particular, it can be provided that the refrigerating and / or freezing device is made in the form of a cabinet and has a usable space that is accessible to the user on its front side (in the case of a display case on the upper side). The storage space can be divided into several compartments, all of which operate at the same or different temperatures. As an alternative solution, only one unit can be provided. Inside the storage space or compartment, storage devices, such as, for example, receiving pockets, drawers or bottle holders (in the case of a chest also spacers), can be provided, in order to ensure optimal storage of the items to be cooled or frozen. use of space.

The useful space can be closed by means of at least one pivot about the vertical axis of the door. In the case of a showcase, a damper can be turned around a horizontal axis or a sliding cover as a closing element. In the closed state, a door or other closing element may be in connection with the casing substantially impermeable to air by means of a circumferential magnetic seal. Preferably, also the door or, accordingly, the other closing element is thermally insulated, wherein the thermal insulation can be achieved by foaming and possibly using vacuum insulation panels, or preferably using a vacuum system and particularly preferably using a full vacuum system. On the inside of the door, door shelves can be provided for the purpose of storing refrigerated products there.

In one embodiment, it may be a small device. In such devices, the usable space, which is defined by the inner wall of the vessel, has, for example, a volume less than 0.5 m ³ , less than 0.4 m ³ or less than 0.3 m ³ .

The outer dimensions of the vessel, respectively, the device, are preferably in the range of 1 m relative to the height, width and depth.

Other details and advantages of the invention are explained in more detail below based on an exemplary embodiment with reference to the accompanying drawings, which depict:

FIG. 1 is a longitudinal section of a refrigeration and / or freezer according to the invention; and

FIG. 2 - part of the thermoelectric element zone, the warm side of which contributes to the evaporation of condensate, on an enlarged scale.

FIG. 1, reference numeral 10 denotes a cabinet of a refrigerating and / or freezing device designed as a cabinet.

The housing 10 has two side walls 12, a cover 14 and a bottom 16. Together with the rear wall and the door, they limit the cooled inner space 100.

As shown in FIG. 1, in both side walls 12, in the wall 14 of the lid and in the bottom 19 a corresponding thermoelectric element 20, 20, is provided.

In principle, exactly one such thermoelectric element can be provided for each wall. However, the invention also covers the case when there are two or more two thermoelectric elements in one or several walls.

It is also possible to arrange one or several thermoelectric elements on the back side of the device, which is also covered by the invention.

Each of the thermoelectric elements 20 is in connection both on the cold side facing the inner space 100 and on the outward warm side with a corresponding heat exchanger 30, 40 transmitting heat, in particular, in a heat-conducting manner. These primary heat exchangers 30, 40 are metal bodies, for example, from aluminum.

During the operation of thermoelectric element 20 through its cold side and with the help of the heat exchanger 30 and the inner wall I, heat is removed from the cooled internal space. This heat is removed through the warm side of the thermoelectric element 20, the heat exchanger 40 and the outer wall A into the environment.

In addition, as shown in FIG. 1, the cross section of the primary heat exchangers 30, 40 increases, starting from the thermoelectric element 20, to the outer wall A, as well as to the inner wall I, which, together with the inner side of the door, limits the cooled inner space 100. Thus, it is possible to distribute the exhaust heat, which, using thermoelectric elements 20, is discharged from the inner space 100, over a large surface without a large temperature gradient.

The outer side of the device is formed by the outer wall A, which in general or in some zones consists of a metal sheet, preferably of aluminum sheet.

In the exemplary embodiment shown here, this metal sheet forms the outer side A of the side walls 12, the covers 14, and also the bottom 16. Accordingly, the rear side and / or the door can also be formed on the outer side.

The metal sheet forming the outer wall A forms the secondary heat exchanger 30, which is connected to the primary heat exchangers 40 in a heat transferring or heat conductive manner.

The inner wall I is also formed using a metal sheet, in particular, an aluminum sheet. The inner wall I is connected to the primary heat exchangers 30 which transfer heat or, accordingly, conduct heat.

The term heat exchanger encompasses, according to this invention, any element that is suitable for heat transfer. In a preferred exemplary embodiment, the heat exchangers are formed using metallic bodies.

Position 50 marked thermal insulation, which passes between the inner wall I and the outer wall And the body. This insulation consists of a volume that is bounded by one or several vacuum-tight films and contains auxiliary material, in particular, perlite. Preferably, other insulating materials, such as, for example, foamed plastic and / or vacuum insulation panels between the inner wall I and the outer wall A, are not provided.

Appropriate thermal vacuum insulation may also be provided for the door or for another closing element.

Peltier elements 20 or other thermoelectric elements are distributed over the geometrical space of the device so that their waste heat is possibly well distributed over the outer shell A of the device. To distribute waste heat throughout the outer shell A, it can be made of aluminum sheet with a thickness of 1 to 2 mm.

Since the amount of heat generated is less than the waste heat, there are no high requirements for heat exchangers in the internal space 100 of the device. Preferably, a metal sheet (for example, an aluminum sheet) is also used for the inner wall of the device, which may be thinner than the metal sheet forming the outer shell A, or it may be identical.

The thermoelectric element 20ʹ located at the bottom is located on its cold side in conjunction with the heat exchanger 30, which on its upper side O forms a condensation surface, i.e. a surface that has a lower temperature compared to neighboring surfaces and / or which represents the lowest temperature in a cooled internal space.

The zone of the bottom-located thermoelectric element 20ʹ is shown on an enlarged scale in FIG. 2. A condensation zone 1 forms around and on the condensation surface of the heat exchanger. Proceeding from this condensation zone 1, on the inner side of the insulating wall of the device, condensate drain 2 leads to evaporation zone 200.

The evaporation zone 200 is formed by an evaporating bowl 4, which traps condensate and is in good thermal connection with the 20ʹ Peltier element. In particular, the evaporating bowl 4 is in direct or at least thermally conductive contact with the heat exchanger 40.

In addition, as shown in FIG. 2, the Peltier element 20ʹ, as well as other Peltier elements of the device according to the invention, can have connecting elements 33, which mechanically firmly compress the Peltier element 20ʹ with heat exchangers 30 and 40.

Thermoelectric element or, respectively, located in the bottom surface of the element 20ель Peltier, designed to control separately using not shown control or adjusting unit, namely, so that its power during the condensation cycle or when the need increases. This leads to the fact that the upper cold side O acquires an even lower temperature, and the lower warm side W acquires an even higher temperature.

This improves condensation as well as evaporation.

During normal operation, the thermoelectric element 20ʹ, as well as other thermoelectric elements, can be used to control the temperature depending on the measured temperature of the internal space.

It is also possible to use an additional thermoelectric element, which lies, for example, on the bottom surface of the device and forms the coldest place there. Thus, this thermoelectric element does not pass between the outer and inner sides of the device, but is located entirely in the cooled inner space and transfers its waste heat to it.

Claims (7)

1. A refrigeration and / or freezing device comprising a cooled inner space and a thermoelectric element, in particular a Peltier element, which is arranged so that the inner space is cooled with a thermoelectric element, and the thermoelectric element is thermally conductively connected to the corresponding heat exchanger the cold side and the outwardly directed warm side, and in the upper side of the heat exchanger that is connected to the cold side of the thermoelectric element forms a condensation surface, which has a lower temperature compared to the adjacent surface of the internal space, and moreover, a condensation zone is formed around and on the condensation surface, characterized in that a drainage element for condensate is provided, which leads from the condensation zone to the evaporation zone, which is formed by the evaporation bowl, which contacts the heat-conducting way with the heat exchanger, which is connected to the warm side of the thermoelectric element. 2. The refrigerating and / or freezing device according to claim 1, characterized in that means are provided by which it is possible to determine whether there is condensate, and a control or adjustment unit connected to these means is provided that increases the capacity of the means for evaporation of the condensate, when the presence of condensate is determined. 3. Refrigeration and / or freezing device according to claim 1 or 2, characterized in that a control or adjustment unit is provided with which the condensation surface is cyclically cooled. 4. The refrigerating and / or freezing device according to claim 3, characterized in that means are provided for determining the opening of the closing element of the device, wherein the control or adjustment unit is designed so that it performs cyclic cooling depending on the detected opening. 5. Refrigeration and / or freezing device according to any one of paragraphs. 1-4, characterized in that a fan is provided, which is located so that it mixes the air in the cooled internal space. 6. Refrigeration and / or freezing device according to claim 1, characterized in that the drain element has such dimensions that the flow of condensate is carried out due to capillary forces.

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