System for lighting refrigeration cabinets using LED lights
The invention relates to a lighting system intended to light the interior of cabinets of the type used in commercial refrigerators, having glass doors. The system is based on a series of three interconnected LEDs mounted on a printed circuit board (PCB). The assembly is inserted into a diffusion tube, the shape of which enables optimized light emission and is designed for sections installed inside cabinet door frames. The LEDs can be powered by a current or voltage source and the manner in which the LEDs are housed along the inner periphery of the door enables the optimized lighting of the items on display.
1. A lighting system for an interior space of a refrigeration cabinet having at least one glass door supported by a door frame, the lighting system comprising:
at least two light modules electrically coupled to each other, each light module being mechanically coupled to the door frame adjacent a periphery of the glass door;
each light module including:
a printed circuit board;
a series of LED sets mounted on the printed circuit board, each LED set including two or three LEDs connected in series, wherein each LED is configured to generate light across a projection angle, each LED set being connected in series or in parallel with the other LED sets;
a driver mounted on the printed circuit board and operably coupled to the series of LED sets, the driver including:
a plurality of capacitors connected in parallel and configured to provide a limited current;
a diode bridge receiving the limited current and configured to provide a rectified current signal; and
a linear preprogrammed integrated circuit including a resistor receiving the rectified current signal and configured to provide a regulated supply of direct current to the series of LED sets;
a housing defining an interior chamber configured to receive the printed circuit board with LEDs and driver, the housing defining a base portion and a diffusion portion, the diffusion portion including a transparent wall formed with a number of diffusion lines sufficient to diffuse light from the LEDs across a projection angle, wherein the housing mechanically engages the printed circuit board thereby to thermally couple the housing to the LEDs; and
a pair of caps sealingly coupled to opposite ends of the housing to hermetically seal the housing interior chamber, each cap being configured to allow electric conductors operably connected to the printed circuit board to pass therethrough.
2. The lighting system of claim 1 , in which an incoming current provided to the driver is 80 mA.
3. The lighting system of claim 1 , in which the driver has an operation range of 90 to 230 VAC.
4. The lighting system of claim 1 , in which each LED has a high luminosity at an input current level of approximately 80 mA.
5. The lighting system of claim 1 , in which the projection angle is 120° to 180° .
6. The lighting system of claim 1 , in which the printed circuit board is enclosed by an injected plastic cabinet filled with resin.
7. The lighting system of claim 1 , in which the housing includes a pair of supports extending partially into the housing interior chamber and securing the printed circuit board within the housing interior chamber, the supports being configured to permit light from each LED to diffuse across a projection angle of 180° .
8. The lighting system of claim 1 , in which each cap is formed of a rubber material.
9. The lighting system of claim 1 , further comprising an adhesive to secure the caps on the housing.
10. The lighting system of claim 1 , in which the diffusion lines are formed on an interior surface of the transparent wall.
11. The lighting system of claim 1 , in which the housing is formed of a plastic material resistant to temperature and deformation.
12. The lighting system of claim 11 , in which the plastic material comprises polycarbonate.
13. The lighting system of claim 1 , further comprising a molding configured to secure each light module to the door frame, and in which the molding is thermally coupled to the housing thereby to further direct heat away from the LEDs.