EP1627583B1 - Case for displaying goods, especially refrigerated display case - Google Patents

Abstract

The chill cabinet is lit by an LED lamp (6) mounted at the top, above the side (5) from which food is withdrawn. Each lamp has a housing (10) with inlets (11) for cool air from the cabinet.

Description

The invention relates to a goods presentation container, in particular a refrigerated display, with a housing and a lighting device based on LED and a cooling device, wherein the lighting device is arranged in the region of a removal opening for goods, and wherein the lighting device has a lamp housing, which is closed at the head by a transparent cover is and receives in its interior individual LEDs and a power supply device for the LED's.

Such goods presentation containers or refrigerated counters are generally used for the merchandise presentation of goods to be cooled and are used both in self-service shops and in customer service in shops such as butchers or the like. In this case, the goods presentation container or the refrigerated display generally has a cooling trough, which is covered by a shelf for goods display. In the cooling pan, a cooling unit is arranged together with a fan, which provides for the generation of a merchandise display overflowing air circulation and ultimately the cooling of the presented goods.

A goods presentation container of the embodiment described above is in the US 2003/0137828 A1 presented. Here, the luminaire housing receives LED's, which are arranged like a line. In addition, it is described in the section [0038] that the luminaire housing must be made hermetically sealed due to the cool environment. In this way one tries to avoid moisture precipitation. However, this hermetic conclusion can lead to a heat build-up inside the luminaire housing. In any case, the lighting device is not optimally cooled, so that in the immediate vicinity of placed goods may be thawed or thawed. You may also experience harmful condensation on. This can affect the overall durability of the presented goods and / or their quality. Here, the invention aims to provide a total remedy.

The invention is based on the technical problem of further developing such a goods presentation container so that a lighting device predestined for the described application is made available and the quality of the cooled goods undergoes no impairment.

To solve this technical problem, a generic goods presentation container in the invention is characterized in that the lamp housing of the lighting device is equipped with inlet openings for circulating in the housing of the goods presentation container cooling air. - The inlet openings can be arranged on opposite sides of the lamp housing, in the direction of the cooling air flow. For example, it is advisable to provide the inlet openings on the two end faces of the lamp housing and / or on two flank sides. As a rule, the luminaire housing is elongated in the form of a cuboid, the cross-sectionally transparent cover for the head-side closure being connected in cross-section to a U-shaped base.

In any case, the inlet openings, which are preferably arranged in the flow direction of the cooling air, ensure that the cooling air can enter the luminaire housing unhindered and flows through it. In this way, the illumination device according to the invention or the LEDs realized there including the power supply device is cooled. In fact, temperatures of less than 10 ° C can be reached at this point.

As a result, the efficiency of LED's is increased over room temperature applications because semiconductor devices in general and LED's with their pn junctions, in particular, have increased efficiency with decreasing temperature. That is, in comparison with the fluorescent tubes used so far in combination with the circulating cooling air to an improved and not deteriorated light output of the lighting device. In addition, the heat development of LEDs is low, because almost all provided electrical power is converted into light energy, so that at this point with conversion rates of well over 80% or even more than 90% can be expected.

The risk that individual goods are affected by a connected with the light radiation heating in their durability, so there is not. Likewise, it can be compared to previous designs with reduced power of the cooling device to work, because the heat generation is reduced. In conjunction with the increased light output and the low energy consumption, there are therefore immediate cost advantages over previous embodiments, which are further enhanced by the fact that the LEDs used have a significantly increased lifetime compared to the fluorescent tubes. Here are the main benefits.

In general, worked with a bar that is equipped with several LEDs, because the goods presentation container regularly widths of one or several meters, so that the correspondingly large-scale merchandise display must be lit over the entire length of the plurality of LEDs. In this case, the invention usually uses as LED's so-called white light LEDs. In this context, the concept of monolithic integration of multiple semiconductor layers and corresponding pn junctions on a substrate has proven itself. The semiconductor materials are such composed of the fact that in the pn-junctions concerned by current injection light with different wavelengths is generated.

In this case, it is possible, for example, to work with three pn junctions per LED, which emit light with wavelengths of the complementary colors red, green and blue, which causes the optical effect of a white light source. This concept has the advantage that, in principle, mixed-color light of any desired color and desired shade can be achieved, resulting in a multiplicity of fields of application. In particular, it is possible to adapt the thus implemented white-light LEDs to the spectrum of a blackbody with about 4000 Kelvin temperature. Such a black spotlight is characterized by a particularly "warm" white color and is perceived by the human eye as extremely pleasant. Of course, other spectra can be simulated with such a monolithic semiconductor device.

As is known, a blackbody or a black body has a spectral intensity distribution which can be determined according to Planck's law of radiation as a function of the temperature (in Kelvin). With white light LEDs, beam sources are now available, which can be described as a first approximation (taking into account an assumed temperature, 4000 K in the example).

In addition, the light emerging from the respective LEDs is optionally filtered and fanned out. This is ensured by a superior optics. This optics may be embodied as prism optics or one of Fresnel lenses and can be advantageously realized in the context of a suitably designed plastic film or plastic cap, as for example in the DE 32 35 250 A1 in connection with an infrared radiation receiver is described.

The invention is based on the recognition that typical white light LEDs radiate usually in a solid angle range of about 60 ° to 80 °, wherein for the described application to illuminate the merchandise display in a Warenpräsentationsbehälter enlarged solid angle of 100 ° to 120 ° or even more desirable. In order to increase this solid angle range, the addressed optics or prism or facet optics is provided and ensures the desired beam expansion to 100 ° to 120 ° or even more.

In order to make installation as cost-effective and inexpensive as possible, the LED-based illumination device or the LED illumination device is combined to form a module together with a power supply device and optionally the optics or prism optics. This module can be easily placed as a unit in the form of a lighting rod similar to a fluorescent tube on the head side of the described removal opening. Due to the compact design also existing goods presentation container with, for example, a fluorescent tube as a lighting device can be easily converted.

In this case, the power supply device in detail at least one mains voltage converter and a rectifier. In addition, a dimmer for power control of the LED's may be provided, which is not mandatory. With the help of the mains voltage converter, the power supply device or the lighting device can be connected directly to the usual AC or mains voltage of 220 V LED-based, which in addition to the compact character simplifies the replacement of previous fluorescent tubes and facilitates installation. That is, the LED-based lighting device according to the invention is ultimately designed as an exchange module in comparison to conventional fluorescent tubes.

In this case, the module or the assembly of the LED's, the optics and the power supply device - as already stated - on its luminaire housing on the addressed inlet openings, which favor the entry of circulating through the goods presentation container cooling air from the cooling device.

Fig. 1

einen erfindungsgemäßen Warenpräsentationsbehälter in der Gestalt einer Kühltheke, perspektivisch, und

Fig. 2

einen Ausschnitt aus Fig. 1 im Schnitt.

In the following the invention will be explained in more detail with reference to a drawing showing only one exemplary embodiment; show it:

Fig. 1

a goods display container according to the invention in the form of a refrigerated counter, in perspective, and

Fig. 2

a section from Fig. 1 on average.

In the figures, a goods presentation container is shown, which is designed as a refrigerated counter. In the context of the illustration, the goods presentation container does not have a restrictive cooling tub 1, which is covered by a goods display 2 or a goods floor 2. Above this there are further goods bottoms 2 '. In or on the cooling trough 1 is a cooling device 3 in the form of a cooling unit with fan for generating a the goods display or the respective goods floor 2, 2 'overflowing air circulation. On the individual goods display 2, 2 'individual goods to be cooled 4 are indicated, which can be removed via associated removal openings 5 by a customer from the goods presentation container. In the region of the respective removal opening 5, namely the head end of this removal opening 5, a lighting device 6 is realized in order to put the goods 4 presented on the goods display 2, 2 'in the right light.

In the context of the invention, the illumination device 6 is an LED-based device, that is to say an LED illumination device 6 has in the longitudinal extension of the goods presentation container via a plurality of LED's 7, which are mounted in series and / or parallel on a bar 8 (see. Fig. 2 ). Below this bar 8, a power supply device 9 is arranged. This power supply device 9 is constructed block-like and has at least one not explicitly shown mains voltage converter and a rectifier.

With the help of the mains voltage converter, a mains voltage (usually 220 volt AC voltage) can be transformed down to values that are compatible with the LED 7 of a few volts. In addition, the downstream rectifier ensures that the individual LEDs 7 are supplied with the required DC low voltage. The individual LED's 7 receiving strip 8 with the underlying power supply device 9 is enclosed in total by a lamp housing 10, which is flowed around by the circulating cooling air, so that the lighting device 6 experiences a total of cooling with the effects already described in the introduction.

In fact, the luminaire housing 10 is closed on the head side with a transparent cover 12, which is embodied here as an optic 12. Inside the lamp housing 10 are the LED's 7 in conjunction with the strip 8 and the power supply device 9. Through inlet openings 11 in the lamp housing 10 can now enter into the housing 1 of the goods presentation container circulating cooling air in the respective lamp housing 10. In this case, the inlet openings 11 are usually arranged in the flow direction of the cooling air, for example on opposite end faces and flat sides of the lamp housing 10, as shown in the Fig. 2 is shown.

The luminaire housing 10 has a base area which is U-shaped in cross-section and which is of the cross-sectionally transparent cover 12 is closed. In the present case, the transparent cover or optics 12 is designed as a prismatic look, as the enlarged section in Fig. 2 makes it clear. In this way, the schematic in the Fig. 2 indicated radiation angle of the individual LED's 7 of about 70 ° to 80 ° increase to values of 100 ° to 120 °. - Via the inlet openings 11, the electrical power supply of the lamp housing 10 and the power supply device 9 and consequently the LED's 7 can be made in addition, so that these inlet openings 11 has an additional benefit.

The optics 12 forms in conjunction with the power supply device 9 and the LED's 7 (and the bar 8 and the lamp housing 10) a compact unit or a functionally ready installation module 7, 8, 9, 10, 11, 12, which is located directly in the head area of Removal opening 5 attach behind a panel 13, as shown in the Fig. 2 will be shown. At the same time, this embodiment predestines the illumination device 6 according to the invention for the replacement of conventional fluorescent tubes at this point. - Not shown is a dimmer, which belongs to the power supply device 9 and performs a power control of the LEDs 7, if necessary. It goes without saying that the dimmer can be operated from the outside.

The LED's 7 are essentially adapted to the spectrum of a blackbody with about 4000 Kelvin temperature and thereby produce a warm white color, which is perceived by the human eye as particularly pleasant and natural. As a result, the goods 4 presented on the goods display 2 and cooled with the aid of the cooling device 3 are immersed in a particularly pleasant light, starting from the lighting device 6.

In this case, the lighting device 6 according to the illustration Fig. 2 arranged at an oblique angle α in comparison to a arranged above the bottom 2 commodity floor 2 ', where a values of about 30 ° to 60 °, preferably 40 ° to 50 °, may assume, in conjunction with the output side of the optics or prism optics 12 achieved beam angle of 100 ° to 120 ° to achieve full illumination of the goods display 2 to the rearmost areas.

Claims (10)

1. Case for displaying goods, in particular refrigerated display case, comprising a housing (1), as well as an LED-based illuminating device (6) and a cooling device (3), the illuminating device (6) being arranged in the region of a removal opening (5) for goods (4), and the illuminating device (6) comprising a lamp housing (10), which is closed at the top by a transparent covering (12), and in its interior comprises individual LEDs (7) as well as a power supply device (9) for the LEDs (7), characterised in that the lamp housing (10) is provided with inlets (11) for cool air circulating in the housing (1).
2. Case for displaying goods according to Claim 1, characterised in that the inlets (11) are arranged on opposing sides of the lamp housing (10), preferably in the direction of flow of the cool air.
3. Case for displaying goods according to Claim 1 or 2, characterised in that a strip (8) comprising a plurality of LEDs (7) is combined with a power supply device (9) to form a sub-assembly (7, 8, 9).
4. Case for displaying goods according to one of Claims 1 to 3, characterised in that the light emerging from the respective LEDs (7) is fanned out in an optical system (12) positioned in front.
5. Case for displaying goods according to Claim 4, characterised in that the optical system (12) is configured as a prismatic optical system (12) and the radiation angle of the individual LEDs (7) increases to approximately 100° to 120° or more.
6. Case for displaying goods according to one of Claims 1 to 5, characterised in that the power supply device (9) has at least one mains power converter and a rectifier.
7. Case for displaying goods according to Claim 6, characterised in that the power supply device (9) additionally has a dimmer for controlling the power of the LEDs (7).
8. Case for displaying goods according to one of Claims 1 to 7, characterised in that the LEDs (7) are configured as white light LEDs.
9. Case for displaying goods according to one of Claims 1 to 8, characterised in that the LEDs (7) are adapted to the spectrum of a black body radiator at a temperature of approximately 4000 Kelvin.
10. Case for displaying goods according to one of Claims 1 to 9, characterised in that the illuminating device (6) is arranged in the top region of the removal opening (5) behind a cover (13).

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