DE29717444U1 - Infrared-free and ultraviolet-free lighting of goods cooled in a refrigerator - Google Patents

Description

Infrared-free and ultraviolet-free lighting of goods cooled in a refrigerated cabinet

The innovation concerns infrared-free and ultraviolet-free lighting of goods cooled in a refrigerated cabinet, with an interior space containing the goods at a low temperature and the outside space, in which people are present and can directly access the cooled goods, at approximately room temperature.

A self-service refrigerated shelf is known from German patent specification No. 3,613,610, in which a cold air flow is directed downwards from outlet openings near an upper shelf in front of the free ends of the shelves arranged at a distance below, and separates the cooled interior containing the goods from the outside area, which is approximately at room temperature and in which people stand to select and access the cooled goods. To illuminate them, one or more spotlights or fluorescent tubes are attached to holders that protrude into the outside area at the top of the refrigerated shelf. The visible light that falls on the cooled goods is inextricably linked to both an infrared component that heats the goods and an ultraviolet component that discolors or makes some goods, such as raw meat, unsightly. Furthermore, the aforementioned light sources tend to decrease in intensity and to shift the spectral range of the emitted light as they burn for longer.

German patent specification No. 4,119,975 describes a glass display case for the effect lighting of objects using 'cold light', as the light guided to the display case wall by light guides no longer contains the infrared component emitted by the light source. Installing light guides to illuminate the goods cooled in the interior of a refrigerated cabinet involves considerable effort.

The innovation is therefore based on the task of installing light sources that emit visible light free of infrared and ultraviolet radiation to illuminate the cooled interior of refrigerated cabinets. These light sources can be operated with as little loss as possible at a constant light intensity and color.

According to the innovation, this task is solved by several rectangular panels, which have numerous light-emitting diodes on their underside, being inserted one after the other on rails that are parallel to the longitudinal dimension of the interior and are mounted on a projection of the refrigeration unit that projects beyond the interior.

In order to illuminate the cooled interior of a refrigerated shelf, in which several shelves are arranged at a distance below the projection, the free end of each shelf can be occupied by rectangular plates in a further development of the innovation, which have numerous light-emitting diodes on their underside and are arranged one behind the other in the longitudinal dimension of the interior.

The installation of the lighting according to the innovation is shown on two different refrigeration units together with details of the lighting in the drawing and is explained in more detail below. They show:

Figure 1 shows the arrangement of the lighting according to the innovation on a self-service refrigerated display case,

Figure 2 the arrangement of the lighting according to the innovation at a service counter and

Figure 3 & 4 Details of the lighting according to the innovation.

Figures 1 and 2 show two well-known and widely used refrigerated cabinets, mainly for food, in elevation and partly in section. The two refrigerated cabinets, namely the self-service shelf in Figure 1 and the service counter in Figure 2, have - as indicated by arrows 10' and 10" respectively - a cold air flow that separates a cooled interior 12' and 12" from the exterior 14' and 14", which is normally at about room temperature and in which people are present. The cold air flow can be kept constantly circulating by a fan (not shown) during operation. To limit it, the self-service shelf in Figure 1 is provided with a transparent roller blind 16, which is brought into the position shown and fixed or raised as required, and is automatically wound up on a roller 18.

The cooled interior 12' or 12" is closed off at the bottom by a plate 20' or 20" on which the objects to be cooled (not shown) in particular

other foodstuffs are stored. In the self-service shelf of Figure 1, in the area of the cooled, vertically extending interior space 12', several shelves 22 to 25 are arranged on the rear wall 26 at a constant distance from one another, on which other items to be cooled (not shown) are stored.

A projection 28' or 28" extends over the interior 12' or 12" of the refrigerated cabinet, as shown in Figure 1 or 2, and forms at least a partial boundary of the cooled interior 12' or 12" upwards. Two rails 30 - only indicated in cross-section in Figures 1 and 2 - are attached to the underside of the projections 28" and 28", the distance between which is adapted to the width of a circuit board 32 or 42 shown in Figure 3 or 4, taking into account the height of a circular module 36 (Figure 3) and other individual parts for establishing electrical connections.

With a minimum width of a refrigeration unit of around 1.25 m, four such boards 32 or 42 are inserted one behind the other on the two rails 30 and are electrically connected to one another and to a power source (not shown) via a transformer. Light-emitting diodes 34 are arranged in 20 rows and 36 columns on the underside of the board 32 (Figure 3), with the module 36 sitting on the board 32 projecting beyond the respective board edge 38 or 39 on both sides.

In the self-service shelf of Figure 1, the free ends of the shelves 22 to 25 are also occupied by the circuit boards 32, which, as the embodiment of Figure 3 shows, have numerous diodes 34 arranged in rows and columns on their underside. This arrangement in rows and columns is advantageous, but, as the embodiment of Figure 4 shows, not absolutely necessary.

In a further embodiment (not shown) of the self-service shelf of Figure 1, the boards 32 are mounted displaced relative to the free end of the projection 28' and/or the shelves 22 to 25 more in the direction of the cooled interior 28'.

A special feature of the embodiment according to Figure 4, which is intended for mass production of the lighting according to the innovation, consists in combining the module containing the electrical circuits and connections with the board 42.

Claims (5)

- 4 CLAIMS FOR PROTECTION 1. Infrared-free and ultraviolet-free lighting of goods cooled in a refrigeration cabinet, wherein an interior space accommodating the goods is at a low temperature and the exterior space, where people are present and can directly access the cooled goods, is at room temperature, characterized in that a plurality of rectangular plates (32; 42) which carry numerous light-emitting diodes (34; 44) on their underside are inserted one behind the other on rails (30) which are parallel to the longitudinal dimension of the interior space (12', 12") and which are mounted on a projection (28 ¹ , 28") of the refrigeration cabinet which projects beyond the interior space (12', 12"). 2. Illumination of goods cooled in a refrigerated shelf according to claim 1, wherein a plurality of shelves are arranged at a distance below the projection, characterized in that the free end of each shelf (22 - 25) is occupied by rectangular plates (32). 3. Lighting according to claim 2, characterized in that the plates (32) are mounted offset from the free end of the projection (28') and/or the shelf (22 - 25) in the direction of the rear wall (26). 4. Lighting according to claims 1 to 3, characterized in that the circuit boards (32) carry a module (36) and further individual parts for the wiring on the broad side opposite the light-emitting diodes (34). 5. Lighting according to claims 1 to 3, characterized in that for series production a control circuit of the diodes (44) is mounted on the upper broad side of the circuit board (42) opposite the diodes (44).