DE102005032121A1 - Household refrigerator for refrigeration of food has heat exchanger which is partly or totally protected by glass or plastic surfaces such that it provides thermal shielding against direct radiant heat - Google Patents

Abstract

The household refrigerator (4) has a heat exchanger (5) which is kept close to the food which is to be cooled. The surface of the heat exchanger has a membrane, which is permeable to water or water vapor. The heat exchanger totally or partly and the food partly is protected by glass or plastic surfaces (2) such that it provides thermal shielding against direct radiant heat (6).

Description

The The aim of the invention is the concept of an energy-efficient refrigerated cabinet with spatially even, temperature constant and condensation-free indoor climate.

The cooling of food in open cooling furniture in Food markets leads to Problems in reaching the required temperatures, locally and temporally uniform temperature control and at the height the energy costs. Furthermore must for optical and hygienic reasons, the condensation or Condensation on the food can be prevented.

The Invention describes a device for more uniform and more constant temperature control and to avoid condensation in the interior of vending coolers Claim 1 of the invention. additionally The energy losses in refrigerators over the Enclosing surfaces and over the openings reduced. As refrigerated furniture both refrigerated shelves as well as freezers designated.

At the current State of the art, the operating principle of refrigerated display cases based or counters on a forced curtain of chilled air along the open area. Here it comes forcibly to an unwanted partial mixing the cooled Air with the warmer Ambient air. This convective heat input has a high Proportion of water vapor in the forced air flow result. In brought thermal contact with the evaporator of the refrigerator, it depends the evaporator and its ribs to a progressive deposition of ice. This insulation layer of ice leads to significant cooling power losses.

Various solutions for preventing or controlling the frost layer have been proposed ( DE 699 07 958 T2 ).

One Periodic heating by stopping the coolant circulation, by electrical resistances Heating Cords or by heated Air was suggested.

Of the Operation of two evaporators (one in defrost mode, the other in cooling condition) as well as dehumidifying the air as well as the series connection from several air curtains were considered.

By the ever-repeated defrosting of the evaporator occurs favorable Milieu for the Development of germs, bacteria and microbes. The food inside the fridge contaminated by air circulation with these pathogens.

At the current state of the art are a constant and uniform temperature distribution of the Interior and the prevention of condensation on the Food and the heat exchangers hardly to combine with a reduction in energy costs and losses.

To reduce energy losses, the openings of the refrigeration cabinets are temporarily covered outside office hours. These covers are usually made of perforated or multilayer films ( DE 102 15 420 A1 ), which, however, have a low insulation effect. Or the covers are made of foamed insulating panels, which insulate well, but the handling of these panels is time-consuming and their storage requires space.

OBJECT OF THE INVENTION

Of the Invention is based on the idea, the heat exchanger to the lower or Tops of individual shelves the refrigerated display cases or to be attached comparatively to the partitions of the freezer cabinets. By this spatially uniform and Foods near arranging the heat exchangers is in refrigerated cabinets to achieve a much more constant indoor climate.

The distribution of the heat exchanger in the cold room is due to the use of a water and water vapor permeable membrane ( DE 198 16 185 C1 ) possible because the condensation water condensing on the heat exchangers is fed through the membrane to the cooling circuit. In addition, heat exchangers and food are shielded by transparent and provided with an infrared-reflective layer glass or plastic strips on the fronts of the shelves as far as possible against the entering through the sales opening direct heat radiation. Preferably, the heat exchangers are completely protected against direct heat radiation (see 1 ). Also in cabinets, this application is feasible, in which the heat exchangers are attached to the partitions of the individual food compartments and their upper visible surface is protected against the heat radiation entering through the open surface (see 3 ). If, for example, 30% of the opening area is covered with such infrared-reflecting layers with a thermal emissivity of 0.2, this reduces the radiation input into the cooling furniture by about 25%. By a temperature-adjustable and adjustable pivoting flap (she hey 2 ), which closes the refrigeration furniture outside of the sales hours, the heat radiation entry through the open sales front is further reduced. In the tempered swing flap and in large parts of the outer shell of the refrigerator furniture vacuum insulation panels to reduce the cold losses are integrated.

1

swiveling, temperature-controlled, high-damping flap

2

lion coated glasses, Etc.

3

With Vacuum panels insulated shell

4

cooling unit

5

heat exchangers with semipermeable membranes

6

thermal radiation

7

vacuum insulation

8th

tempered swiveling flap

9

heatable Layer with heat transfer fluid

10

semipermeable membrane

Claims (4)

Sales refrigerated furniture characterized in that a) that the heat exchanger ( 5 ) is located close to the foods to be cooled. b) that the surface of the heat exchanger ( 5 ) consists of a water or water vapor permeable membrane. c) that all or part of the heat exchangers and the food are thermally shielded by low-e coated surfaces of glass or plastic against the direct heat radiation entering through the sales opening. Cooling furniture thereby in a) that the temporary cover during the period the sale insert in almost horizontal position on refrigerated shelves and is located in an almost vertical position in freezer cabinets. b) that for the refrigerator furniture interior visible area both tempered and with a functioning according to claim 1 semipermeable membrane is coated. c) that the temporary cover to the outside of the Cooling furniture all over or partially isolated by a vacuum insulation panel. Refrigerated furniture after Claim 2, characterized in that the edge bond of the temporary cover of the refrigerator in completely or partially closed by overlapping vacuum insulation panels or by an evacuated or highly insulating frame system Interfaces of the Cover with the refrigerator thermally isolated. Refrigerated furniture after Claim 1 or 2, characterized in that the opaque outer surfaces of the refrigerated cabinet completely or partly by vacuum insulation panels against high thermal Losses of the refrigerator furniture interior against the ambient air of the outer space are isolated.