Variable colour temperature lighting device for domestic electrical appliances

Patent metadata

Field	Value
Publication number	US-10724732-B2
Application number	US-201816036981-A
Country	US
Kind code	B2
Filing date	Jul 17, 2018
Priority date	Jul 17, 2017
Publication date	Jul 28, 2020
Grant date	Jul 28, 2020

Abstract

A lighting device for lighting an interior of a domestic electrical appliance is configured to be operated in different lighting modes which differ from one another by the spectral composition of the light of the lighting device delivered into the appliance interior. In some embodiments, the lighting device comprises two light-emitting diodes which differ from one another in terms of the spectral content of the light delivered thereby. The different lighting modes of the lighting device differ from one another by a different operating combination of the light-emitting diodes. By varying the duty cycle and the pulse frequency of a pulse-width-modulated control signal, a control assembly is able to transmit two different pieces of control information to the lighting module in order to control the two light-emitting diodes individually.

First claim

What is claimed is:

1. A lighting device for lighting an interior of a domestic electrical appliance, the lighting device comprising a plurality of light sources and an evaluation unit, wherein the plurality of light sources are configured to emit light of different spectral contents,
wherein the lighting device is configured to be operated in different operating modes which differ from one another by a different operating combination of the light sources so as to create a respective different spectral composition of the light of the lighting device delivered into the appliance interior,
wherein the evaluation unit is adapted to determine from a pulse-width-modulated control signal a first control variable and a second control variable, the first control variable being representative of the duty cycle of the control signal and the second control variable being representative of the period of the control signal,
wherein the evaluation unit is further adapted to control a first light source from the plurality of light sources in dependence on the first control variable and to control a second light source from the plurality of light sources in dependence on the second control variable.

2. The lighting device according to claim 1 , wherein the lighting modes comprise at least two lighting modes in which the light of the lighting device delivered into the appliance interior is white light of different colour temperatures.

3. The lighting device of claim 1 , wherein the plurality of light sources are LEDs.

4. The lighting device according to claim 1 , wherein the light sources comprise at least two white light sources which are configured to emit white light of different colour temperatures.

5. The lighting device according to claim 1 , wherein the light sources comprise at least one light source selected from the group consisting of a red light source, a blue light source, and a yellow light source.

6. The lighting device according to claim 1 , wherein the operating combinations comprise at least two operating combinations which differ from one another by a different combination of radiation intensities of at least two of the light sources.

7. The lighting device according to claim 1 , wherein the operating combinations comprise a first operating combination in which a specific one of the light sources is switched off, and at least a second operating combination in which the specific light source is switched on.

8. The lighting device according to claim 1 , comprising a reflective or/and transmissive diffusion structure for mixing the light of each of the light sources.

9. The lighting device according to claim 1 , wherein the lighting device further comprises a transmissive light outlet structure which is common to each of the plurality of light sources and from which the light of the lighting device emerges into the appliance interior.

10. A domestic electrical appliance comprising:
an appliance interior which can be closed by a door, and
a lighting device for lighting the appliance interior,
wherein the lighting device is configured to be operated in different operating modes which differ from one another by the spectral composition of the light of the lighting device delivered into the appliance interior;
wherein the domestic electrical appliance is selected from a group consisting of a fridge, an oven, and a washing machine;
wherein when the domestic electrical appliance selected is the oven, the appliance interior forms a cooking chamber wherein the oven comprises a control device which is configured, in dependence on the detection of a closed state of the door, to effect operation of the lighting device in a first lighting mode and, in dependence on the detection of an open state of the door, to effect operation of the lighting device in a second lighting mode, wherein in the first lighting mode the light delivered by the lighting device into the cooking chamber has a higher red component than in the second lighting mode;
wherein when the domestic electrical appliance is the refrigerator, the appliance interior forms a cooling chamber, wherein the refrigerator comprises a control device which is configured, in dependence on the detection of a state of relatively slight loading of the cooling chamber, to effect operation of the lighting device in a first lighting mode and, in dependence on the detection of a state of relatively great loading of the cooling chamber, to effect operation of the lighting device in a second lighting mode, wherein in the first lighting mode the light delivered by the lighting device into the cooling chamber has a higher blue component than in the second lighting mode; and
wherein when the domestic electrical appliance is the washing machine, the appliance interior is formed by a rotating washing vessel, wherein the washing machine comprises a control device which is configured to effect operation of the lighting device in different lighting modes depending on the result of a colour analysis of laundry introduced into the washing vessel.

11. A lighting device for lighting an interior of a domestic electrical appliance, wherein the lighting device is configured to be operated in different operating modes which differ from one another by the spectral composition of the light of the lighting device delivered into the appliance interior, wherein the lighting device comprises a plurality of LEDs configured to emit light of different spectral contents, wherein the lighting modes differ from one another by a different operating combination of the light sources,
wherein the lighting device comprises a circuit board having mounted thereon a plurality of groups of individually controllable light-emitting diodes, each light-emitting diode of each group having a spectral composition of emitted light which is different from the spectral composition of emitted light of every other light-emitting diode of the group, wherein each group of the plurality of groups has the same combination of spectrally different light-emitting diodes.

12. The lighting device according to claim 11 , wherein the plurality of groups are arranged in a straight row.

13. The lighting device according to claim 9 , wherein the transmissive light outlet structure is in the form of a pane.

14. The lighting device according to claim 9 , further comprising a reflecting body which forms a reflecting surface, wherein at least part of the light emitted by the plurality of light sources first strikes the reflecting surface, which deflects the light in the direction towards the transmissive light outlet structure, wherein the reflecting surface provides at least in a part-region thereof a diffusely scattering effect.

15. The domestic electrical appliance according to claim 10 , wherein the lighting device comprises a plurality of light sources and an evaluation unit which is adapted to:
determine from a pulse-width-modulated control signal a first control variable which is representative of the duty cycle of the control signal;
determine from the pulse-width-modulated control signal a second control variable which is representative of the period of the control signal;
control a first light source of the plurality of light sources based on the first control variable; and
control a second light source of the plurality of light sources based on the second control variable.

16. The lighting device according to claim 1 , wherein at least one of the light sources is a white light source.

Assignees

• Emz Hanauer Gmbh & Co Kgaa

Inventors

• Schenkl Johann
• Signorino Manfredi
• Brabec Martin
• Laubscher Moritz

Classifications

• F21Y2113/13

  comprising an assembly of point-like light sources · CPC title

• H05B45/325

  Pulse-width modulation [PWM] · CPC title

• H05B45/20

  Controlling the colour of the light · CPC title

• F21W2131/307

  for ovens · CPC title

• F21W2131/305

  for refrigerators · CPC title