WO2009124937A1

WO2009124937A1 - Lighting device and relative method of production

Info

Publication number: WO2009124937A1
Application number: PCT/EP2009/054150
Authority: WO
Inventors: Ivo Del Ben
Original assignee: Led Go Srl
Priority date: 2008-04-08
Filing date: 2009-04-07
Publication date: 2009-10-15
Also published as: ITUD20080076A1

Abstract

Lighting device (10) and relative method of production, comprising a support structure (13) that supports one or more sources of light (15) to illuminate a determinate surface, and insulating members associated with the support structure (13) and disposed in cooperation with the sources of light (15) to determine the insulation from the outside of the sources of light (15). The insulating members comprise an at least partly transparent layer of resin (25), conformed so as to completely drown at least the sources of light (15), in order to insulate them completely from the outside.

Description

"LIGHTING DEVICE AND RELATIVE METHOD OF PRODUCTION"

FIELD OF THE INVENTION

The present invention concerns a lighting device, such as for example a lamp, a streetlight, a spotlight or suchlike, provided with a source of light, for example incandescent, gas, LED or other, to emit a desired beam of light on an area to be illuminated. In particular, but not exclusively, the lighting device according to the present invention is configured to be installed in applications where it is frequently subjected to the action of atmospheric agents, for example street lamps, luminous tiles or other and/or to contact with water, for example in the boating industry.

BACKGROUND OF THE INVENTION

Lamps, streetlights, spotlights or suchlike are known, provided with a source of light, for example incandescent, gas, LED or other, to emit a desired beam of light on an area to be illuminated.

Lamps are also known, or other lighting devices, specific for illuminating external areas, or for the naval industry.

In this type of lighting devices, for safety reasons, all the electric and electronic components must be protected and completely insulated from the outside, to prevent the action of water or other atmospheric agents from negatively affecting the functioning of the components, causing short circuits which can even have serious consequences.

It is known to make such lighting devices by providing insulating and hermetic closing members or mechanisms, so as to respect specific normalized insulation classes, such as for example the one identified by the abbreviation IP68, or suchlike.

It is also known to provide members, such as insulation packings, disposed in the join zones of the structural components of the lighting device, to prevent the water from filtering toward the electric components. However, these known solutions need specific design and working steps for the structural components in order to make the housing seatings for the packings. Furthermore, the packings must be assembled with expertise and by specialized staff, since if they were positioned erroneously, this might result in the electric components not being properly insulated.

Therefore, the known insulating solutions for lighting devices are particularly complex and costly.

Insulating solutions are also known with snap-in hermetic closing elements, or consisting of complex barriers or walls cooperating mechanically with each other.

These solutions are very expensive and can only be used in limited and sectional applications.

Purpose of the present invention is to achieve a lighting device that, giving the same lighting coverage, is simple and economical to make, and which guarantees effective insulation preventing external agents from negatively affecting the functioning of the electric components.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea. A lighting device according to the present invention comprises a support structure that supports one or more sources of light, to illuminate a determinate surface.

In accordance with the above surface the lighting device according to the present invention also comprises insulating means associated with the support structure and disposed in cooperation at least with the sources of light, to determine the insulation of the latter from external agents, such as water, humidity or others which could compromise the correct functioning thereof.

According to a characteristic feature of the present invention, the insulating means comprise at least a layer of at least partly transparent resin, conformed so as to completely drown at least the sources of light, so as to insulate them completely from the outside.

In this way, the sources of light, and also any other possible electric and electronic components, are insulated by means of complete incorporation in the layer of resin, and hence without needing to provide packings and/or other complex and expensive hermetic closing mechanisms.

The layer of resin is deposited and conformed directly on the sources of light, or other electric compartment to be drowned, without using packings and without designing and making beforehand housing seatings or other complex mechanical interventions on the support structure.

This characteristic feature of the present invention thus allows to reduce the times and costs of making the device, and also to substantially eliminate the disadvantages connected to the erroneous assembly of the packings. According to a variant, the layer of resin comprises at least a bi-component resin, in which the reciprocal dosage of the components is such as to define a colloidal or gelatinous consistency of the layer of resin.

In this way, the gelatinous consistency of the layer of resin is able to absorb possible heat deformations due to the different temperatures between the sources of light and the external environment, limiting to a minimum the risk of surface cracks or fissures.

According to another variant, the bi-component resin comprises at least a polymer with a, for example, epoxy, polyurethane, silicon or other base, and a hardening agent, such as for example a base of isocyanides, amines or other, where the polymer is dosed to a percentage varying from about 50% to about 90%, whereas the hardening agent is dosed to a percentage varying from about 50% to about 10%.

According to this variant the possible bi-component resins obtained with the above percentage compositions and materials have at least characteristics of resistance to ageing and to ultraviolet rays, self-extinguishing and resistance to high temperatures, stability and chemical inertia, compatibility with the electric or electronic components, optical transparency and easy coloring.

According to a variant, at least the polymer is subjected to a surface treatment of the plasma type and/or plasma-corona type, to confer on the bi-component resin characteristics of impermeability and adhesion.

According to a variant, in which the support structure can be coupled with a transparent cover element which determines the closure of the sources of light in a defined area, the layer of transparent resin substantially has the same gelatinous consistency over its whole section.

In this variant, the layer of resin has at least characteristics of adhesion such as to guarantee the attachment of the transparent covering element.

According to another variant, the layer of resin comprises at least an external part with characteristics of surface hardness in order to function as a protection, and an internal part with said characteristics of gelatinous consistency in order to absorb heat deformations.

A method to produce a lighting device according to the present invention provides, after a first step to assemble at least the sources of light on the support structure, at least a second step in which at least on the sources of light a layer of at least partly transparent resin is deposited, so as to completely drown at least the sources of light, and to insulate them completely from the outside.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some preferential forms of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a partly sectioned lateral view of a first form of embodiment of a lighting device according to the present invention;

- fig. 2 shows a cross section from II to II of fig. 1 ; - fig. 3 is a partly sectioned lateral view of a second form of embodiment of a lighting device according to the present invention;

- fig. 4 shows a cross section from IV to IV of fig. 3.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF

EMBODIMENT With reference to figs. 1 and 2, a lighting device 10 in this case is applied to illuminate a roadway, for example mounted on a lighting device of the type described in the Italian patent application IT-A-UD2008A000032 in the name of the present Applicant.

In this case, the lighting device 10 comprises a support structure 13, oblong in shape, and a plurality of LEDs 15, in this case three.

The support structure 13 is made with an aluminum profile and is conformed so that the LEDs 15 can be disposed in a row on the length of the support structure 13. Each LED 15 is electronically connected to an electronic command card 18 attached on the bottom of the support structure 13. In this case the electronic command card 18 is common for all three LEDs 15.

The support structure 13 also comprises two terminal stoppers 16 and a transparent protective cover 17, attached to the support structure 13 and able to define an internal compartment 19 in which the electronic command card 18 and the LEDs 15 are housed.

To give an example, the LEDs 15 are all identical and are the type fed at 24 V, able to emit a cold white light with a luminosity comprised between about 70 lumen/watt and about 100 lumen/watt. A relative collimation lens 21 is associated with every LED 15 and, depending on the specific sector of the surface S to which the beam of light emitted by the LED 15 is directed, has a different degree of opening, so as to optimize the distribution of the light emitted by the individual LEDs 15.

The device 10 according to the invention also comprises a layer of resin 25 disposed completely inside the internal compartment 19, so as to completely drown the LEDs 15 and the electronic command card 18, with all its electric and electronic components.

In this way, the LEDs 15 and the electronic command card 18 are completely insulated from external agents, achieving a class IP68 degree of insulation. The layer of resin 25 is substantially defined by a bi-component resin consisting of a polymer, such as a monomer resin, for example of the silicon, polyurethane or epoxy type, suitably treated, and a reaction activator hardener, for example isocyanide or amine, suitably treated.

Advantageously, at least the polymer is subjected to a surface treatment of the plasma and/or plasma-corona type, in order to confer on the bi-component resin characteristics of impermeability and adhesion.

In particular, the bi-component resin has a dosage of the monomer resin to a percentage varying from about 50% to about 90%, and the hardener agent to a percentage varying from about 50% to about 10%. Other characterizations can be obtained by adding additives and fillers, to obtain characteristics of refraction and diffraction of the light, self-extinguishing and heat conductivity.

In the form of embodiment shown in figs. 3 and 4, the lighting device 10 according to the invention comprises a support structure 13 that, unlike the support structure 13 in the previous embodiment, defines only a base wall, while the transparent cover 17 has a cross section with an arched shape so as to substantially define the external design of the device 10 In this case too, the layer of resin 25 is provided in the internal compartment

19, and functions as an insulation for the LEDs 15 and the electronic command card 18.

It is clear, however, that modifications and/or additions of parts may be made to the lighting device 10 as described heretofore, without departing from the field and scope of the present invention.

For example, it comes within the field of the present invention to provide that the device 10 does not have the transparent cover 17. In this embodiment, the layer of resin 25 comprises an external protective part with characteristics of surface hardness, and an internal insulation part with a gelatinous consistency in order to absorb the heat deformations due to the heat of the LEDs 15.

It is also clear that, although the present invention has been described with reference to specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of lighting device, and relative method of production, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

Claims

1. Lighting device comprising a support structure (13) able to support one or more sources of light (15) to illuminate a determinate surface, and insulating means associated with said support structure (13) and disposed in cooperation at least with said sources of light (15) to determine the insulation from the outside of said sources of light (15), characterized in that said insulating means comprise at least a layer of resin (25), at least partly transparent, conformed so as to completely drown at least said sources of light (15), in order to insulate them completely from the outside.

2. Device as in claim 1, characterized in that said layer of resin (25) comprises at least a bi-component resin with a colloidal or glutinous consistency, such as to absorb possible heat deformations due to the different temperatures between said sources of light (15) and the external environment.

3. Device as in claim 2, characterized in that said bi-component resin comprises at least a polymer and a hardening agent, in which said polymer is dosed to a percentage varying from about 50% to about 90%, whereas said hardening agent is dosed to a percentage varying from about 50% to about 10%.

4. Device as in claim 3, characterized in that at least the polymer is subjected to a surface treatment of the plasma and/or plasma-corona type, in order to confer on the bi-component resin characteristics of impermeability and adhesion.

5. Device as in any claim hereinbefore, wherein said support structure (13) is able to be coupled with a transparent element (17) able to determine the closure of the sources of light (15) in a defined area (19), characterized in that said layer of resin (25) has a uniform consistency over its whole section.

6. Device as in any claim from 1 to 5, characterized in that said layer of resin (25) comprises at least an external part with characteristics of surface hardness, and an internal part with characteristics of absorbing the heat deformations.

7. Method to produce a lighting device comprising a support structure (13) able to support one or more sources of light (15) to illuminate a determinate surface, and insulating means associated with said support structure (13) and disposed in cooperation at least with said sources of light (15) to determine the insulation from the outside of said sources of light (15), said method comprising at least a first step, in which said sources of light (15) are mounted on said support structure (13), characterized in that it comprises at least a second step, in which at least on said sources of light (15) a layer of resin (25) is deposited, at least partly transparent, so as to completely drown at least said sources of light (15) and insulate them completely from the outside.