AU2005203137B2

AU2005203137B2 - Display case for goods, in particular, a cooling display case

Info

Publication number: AU2005203137B2
Application number: AU2005203137A
Authority: AU
Inventors: Peter Ernst; Robert Ochsenschlager
Original assignee: Aldi Einkauf GmbH and Co OHG
Current assignee: Aldi Einkauf GmbH and Co OHG
Priority date: 2004-08-18
Filing date: 2005-07-19
Publication date: 2010-12-09
Anticipated expiration: 2025-07-19
Also published as: CY1109704T1; EP1627583B1; AU2005203137A1; SI1627583T1; DE502005008268D1; EP1627583A1; ATE444690T1; DE102004042854A1

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The chill cabinet is lit by an LED lamp (6) mounted at the top, above the side (5) from which food is withdrawn.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

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL TO BE COMPLETED BY APPLICANT Name of Applicant: ALDI EINKAUF GMBH & CO. OHG Actual Inventors: ERNST, Peter, of MbnchstraBe 10, 45478 Miilheim/Ruhr, Germany; OCHSENSCHLAGER, Robert, of Lohbecker Berg 9, 45470 Mtilheim/Ruhr, Germany Address for Service: CALLINAN LAWRIE, 711 High Street, Kew, Victoria 3101, Australia Invention Title: DISPLAY CASE FOR GOODS, IN PARTICULAR, A COOLING DISPLAY CASE The following statement is a full description of this invention, including the best method of performing it known to us:- -2 DISPLAY CASE FOR GOODS, IN PARTICULAR, A COOLING DISPLAY CASE Description The invention relates to a display case for goods, particularly a cooling display case, 5 with a housing, an LED-based illuminating-device, and a cooling-device; the illuminating device is preferably arranged in the region of an opening for the removal of goods, and has a light-housing which is covered by a transparent cover at the top and which accommodates, in its interior, individual LEDs and a power supply unit for the LEDs. Such goods display and cooling cases are generally used for the display of goods that 10 require to be cooled, and are used both in self-service stores and in stores with customer service, such as butcher shops or the like. These display and cooling cases generally have a cooling tray, which is covered by a floor or bottom shelf for displaying the goods. In the cooling tray, a cooling unit is arranged, together with a blower, serving to produce circulating air flowing over the goods displayed and thus cooling them. is A goods display case of the above-mentioned design is described in US 2003/0137828 Al. The light-housing concerned contains LEDs in strip form. In paragraph [0038], it is also stated that the light-housing has to be hermetically sealed, due to the cool environment. This is done in an attempt to prevent condensation. This hermetic sealing can, however resulting in heat building up inside the light-housing. In any case, the illuminating-device is not optimally 20 cooled, and therefore, goods placed in its immediate vicinity may start to thaw, or may thaw out. Possibly, harmful formation of condensate may also occur. The overall result may be to impair the storage life and/or quality of the goods displayed. In this regard, the invention will provide an overall remedy. The invention is based on the technical problem of how to further develop a goods 25 display case of the above-described kind, so as to provide an illuminating-device for the described application, without impairing the quality of the goods being cooled. To solve this technical problem, the present invention provides a goods display case, particularly a cooling case, with a housing, a LED-based illuminating-device, and a cooling device, said illuminating-device being arranged in the region of an opening for removing 30 goods, and said illuminating-device having a light-housing sealed at the top with a transparent cover and having in its interior individual LEDs and a power supply unit for the LEDs, wherein the light-housing has inlet openings for cooling-air circulating in the housing. 18/07/05,sw1505 1speci,2 -3 These inlet openings can be arranged on opposite sides of the light-housing, in the direction in which the cooling-air flows. For example, it is advisable to provide inlet-openings on both ends of the light-housing and/or on two sides thereof. As a rule, the light-housing is in the form of an elongated right parallelepiped, with a U-shaped base when viewed in cross 5 section that is sealed at the top by a transparent cover which is bow-shaped when viewed in cross-section. In any case, the inlet-openings, which are preferably arranged in the direction of flow of the cooling-air, enable the cooling-air to enter the light-housing unhindered and to flow through it, thus cooling the illuminating-device of the invention, including the LEDs and the 10 power supply unit, with temperatures of less than 10*C being achieved in practice. This increases the efficiency of the LEDs over their efficiency when used at room temperature, because, as is well known, semiconductor components generally - and LEDs with their pn-junctions in particular - show increased efficiency as the temperature decreases. This means that, due to the circulating cooling-air, the light output of the illuminating-device is is improved, and not degraded, relative to that of the fluorescent tubes used hitherto. In addition, little heat is generated by LEDs, because nearly all of the electric power supplied is converted into light energy, with the result that conversion rates of distinctly more than 80%, or even more than 90%, can be counted on. There is therefore no danger that the shelf-life of individual goods will be impaired by 20 heat from the emission of light. Likewise, the cooling-device can be operated at lower power than with prior embodiments, because less heat is generated. The increased light produced, and low amount of energy consumed, therefore result in direct cost benefits over prior embodiments, and these are increased still further in that the LEDs used have a considerably longer life than fluorescent tubes. Herein lie the essential advantages of the invention. 25 Generally a strip fitted with a number of LEDs is used, because the goods display case is normally one or more metres wide, and the correspondingly-large goods displays have to be illuminated over their entire length by a multiplicity of LEDs. The LEDs used in the invention are generally those known as "white-light LEDs". In this regard, the concept of solid-state integration of a number of semiconductor layers and corresponding pn-junctions on a substrate 30 has proved its worth. The semiconductor materials are put together in such a way that light of different wave-lengths is produced at the pn-junctions concerned, by current-injection. 18/07/05,sw 1505 Ispeci,3 -4 For example, it is possible to utilize three pn-junctions per LED, emitting light with wavelengths of the complementary colours red, green, and blue, thereby producing the optical effect of a white-light source. The advantage with this design is that it is, in principle, possible to obtain mixed-coloured light of any desired colour and shade, thus giving rise to a 5 multiplicity of areas of application. In particular, it is possible to match such white-light LEDs to the spectrum of a black-body radiator with a temperature of approx. 4000 Kelvin. Such a black-body radiator is characterized by producing a particularly warm white colour, which is experienced as particularly pleasant by the human eye. Of course, other spectra can also be produced with a solid-state semiconductor component of this type. 10 As is known in the art, a black body or black-body radiator has a spectral intensity distribution that can be determined by Planck's radiation law, as a function of temperature (in Kelvins). With white-light LEDs, radiation sources are now available which can be described thereby as a first approximation (with respect to a given temperature, e.g. 4000 K). In addition, the light emitted from the LEDs can, if desired, be filtered and fanned out. is This is done by means of an optical system placed in front. This can be a prismatic lens or a lens consisting of Fresnel lenses, and can, advantageously, be embodied as a suitably-designed plastic sheet or plastic cap, as described, for example, in DE 32 35 250 Al in connection with an infrared radiation receiver. In this regard, the invention proceeds from the known fact that typical white-light 20 LEDs generally emit in a solid-angle range of approx. 60 to 800, whereas for the task described here, which is to illuminate the goods on display in a goods display case, larger solid angles of 100 to 1200 or even more are desirable. In order to increase this solid-angle range, said optical system, i.e. prismatic lens or faceted lens, is placed in front, and widens the beam, as desired, to 100 per 1200 or even more. 25 To make installation as inexpensive and convenient as possible, the LED-based illuminating-device is combined with a power supply unit, and possibly the optics or prismatic lens, to create a module in the form of an illuminating-rod, similar to a fluorescent tube, that can be readily installed at the top of the goods-removal opening described above. Due to its compact design, it can also be easily retrofitted to existing goods display cases, to replace e.g. 3o a fluorescent tube as the illuminating-device. In detail, the power supply unit used has at least one mains voltage transformer and a rectifier. In addition, it may have a dimmer for controlling the power to the LEDs, but this is 18/07/05,sw 1505 ispeci,4 -5 not mandatory. By means of the mains voltage transformer, the power supply unit and the LED-based illuminating-device can be connected directly to the normal mains power (220 V alternating voltage), and this, together with its compactness, simplifies its use as a replacement for fluorescent tubes and makes it easier to install. This means that the LED-based 5 illuminating-device of the present invention is, in the final analysis, designed as a replacement module for conventional fluorescent tubes. As already mentioned, the module consisting of the LEDs, lens, and power supply unit, has in its light-housing the above-mentioned inlet openings, which facilitate entry of the cooling-air, produced by the cooling-device, that is circulating in the goods display case. 10 The invention will now be described in greater detail with regard to one embodiment, shown in the accompanying drawings, in which: Fig. 1 is a perspective view of a cooling goods-display case according to the present invention; and Fig. 2 shows a detail from Fig. 1. 15 The Figures show a goods display case in the form of a cooling display case. In the drawings, the goods display case has - but is not limited to - one cooling tray 1, which is covered by a goods display floor or bottom shelf 2, above which there are additional goods shelves 2'. In or on the cooling tray 1, a cooling-device 3 is provided, in the form of a refrigerating apparatus with a blower for producing circulating air that flows over the goods 20 and shelves 2, 2'. On the individual shelves 2, 2', individual goods 4 to be cooled are shown, and these can be removed from the display case by a customer, through the respective removal openings 5. In the region of each removal opening 5, i.e. at the top thereof, an illuminating device 6 is provided, to show the displayed goods 4 on the shelves 2, 2' in a good light. The illuminating-device 6 of the present invention is LED-based, i.e. it is an LED-type 25 illuminating-device 6. It comprises a multiplicity of LEDs 7 in the goods-display case's longitudinal direction, these being mounted in series and/or parallel on a strip 8 (see Fig. 2). A power supply unit 9 is arranged beneath this strip 8. This power supply unit 9 is of modular construction, and has at least one mains voltage transformer (not shown) and a rectifier. 30 By means of the mains voltage transformer, a mains voltage (generally 220 V alternating-current voltage) can be transformed down to levels of a few volts, suitable for the LED 7. In addition, the rectifier connected in series to the output side of the transformer serves 18/07/05,swl505 Ispeci,5 -6 to provide the individual LEDs 7 with the required low, direct-current voltage. The strip 8 bearing the individual LEDs 7, together with the power supply unit 9 beneath it, is surrounded by a light-housing 10 around which the circulating cooling-air flows, with the result that the whole illuminating-device 6 undergoes cooling, with the effects that have already been 5 described in the introduction. The light-housing 10 is sealed at the top with a transparent cover 12 in the form of a lens 12. The LEDs 7, in conjunction with the strip 8 and the power supply unit 9, are inside the light-housing 10. Inlet openings 11 are provided in the light-housing 10; and cooling-air, circulating anyway in the housing 1 of the goods display case, can now enter, through said 10 inlet-openings, into the light-housing 10 concerned. The inlet-openings 11 are as a rule arranged in the direction of cooling-air flow, e.g. on opposite ends and flat sides of the light housing 10, as shown in Figure 2. The light-housing 10 has a base surface which is U-shaped in cross-section, and which is sealed by the transparent cover 12, which has a bow-shaped cross-section. In the present 15 case, the transparent cover 12 and lens 12 is designed as a prismatic lens, as is clearly shown by the enlarged detail in Figure 2. In this way, the angle of the beam from the individual LEDs 7, shown diagrammatically in Figure 2, can be increased from approx. 70- 800 to 100-120*. In addition, the electric power supply to the light-housing 10 and the power supply unit 9, and hence to the LEDs 7, can also be provided through the inlet-openings 11, which thus serve an 20 additional purpose. The lens 12, power supply unit 9, and LEDs 7 (and also the strip 8 and the light housing 10) form a compact, ready-to use module 7, 8, 9, 10, 11, 12, which can be mounted in the top region of the goods-removal opening 5, directly behind a screen 13, as shown in Figure 2. At the same time, this design makes the inventive illuminating-device 6 suitable for 25 replacing conventional fluorescent tubes in this position. Not shown is a dimmer belonging to the power supply unit 9 and serving as a power control for the LEDs 7 if necessary. Obviously the dimmer can be operated from the outside. The LEDs 7 are essentially matched to the spectrum of a black-body radiator with a temperature of approx. 4000 Kelvin, and thus produce a warm white colour which is 30 experienced as particularly agreeable and natural by the human eye. As a result, the goods 4 being displayed on the display shelf 2 and being cooled by means of the cooling-device 3 are bathed in a particularly pleasant light from the lighting-device 6. 18/07/05,sw 15051 speci,6 -7 The illuminating-device 6, as shown in Figure 2, is arranged at an oblique angle a relative to an additional goods display shelf 2' arranged above the bottom goods display shelf 2. The angle a may be approx. 30 to 600, and preferably 40 to 50*, so that, with the beam angle of 100 to 1200 achieved at the output side of the optics or prismatic lens 12, full illumination 5 of the goods display 2 can be achieved, even to the farthest-back regions thereof. Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof. 18/07/05,sw15051 speci,7

Claims

1. A goods display case, particularly a cooling case, with a housing, a LED-based illuminating-device, and a cooling-device, said illuminating-device being arranged in the region of an opening for removing goods, and said illuminating-device having a light-housing sealed at the top with a transparent cover and having in its interior individual LEDs and a power supply unit for the LEDs, wherein the light-housing has inlet openings for cooling-air circulating in the housing.

2. A goods display case as claimed in claim 1, wherein the inlet openings are arranged on opposite sides of the light-housing, preferably in the direction of flow of the cooling-air.

3. A goods display device as claimed in claim 1 or 2, wherein a strip is combined with a multiplicity of LEDs and with a power supply unit to form a module.

4. A goods display device as claimed in any of claims 1 to 3, wherein the light emerging from the respective LEDs is fanned out in an optical system placed in front of them.

5. The goods display device as claimed in claim 4, wherein the optical system is a prismatic lens, and the angle of radiation of the individual LEDs is increased to approx. 100 to 1200 or more.

6. A goods display device as claimed in any one of claims 1 to 5, wherein the power supply unit has at least one mains voltage transformer and a rectifier.

7. A goods display device as claimed in claim 6, wherein the power supply unit has, in addition, a dimmer for controlling the power to the LEDs.

8. A goods display device as claimed in any one of claims 1 to 7, wherein the LEDs are white-light LEDs. 18/07/05,sw 1505 1speci,8 -9

9. A goods display device as claimed in any one of claims 1 to 8, wherein the LEDs are matched to the spectrum of a black-body radiator with a temperature of approx. 4000 Kelvin.

10. A goods display case as claimed in any one of claims 1 to 9, wherein the illuminating-device is arranged in the top region of the goods-removal opening, behind a screen.

11. A goods display case substantially as hereinbefore described with reference to any one of the drawings. Dated this 18 th day of July 2005 ALDI EINKAUF GMBH & CO. OHG By their Patent Attorneys: CALLINAN LAWRIE 18/07/05,sw15051 speci,9