Lighting Device Field of the invention

The present description relates to lighting devices.

Various embodiments can relate to lighting devices having a box-like housing for an electrically-powered lighting source which generates heat during operation.

Various embodiments can relate to lighting devices which use, as a source of light radiation, LED radiation sources.

Background of the invention

In the construction of light sources, for example for appli ^¬ cations in general lighting technology, it is important to be able to reconcile different requirements such as, for exam ^¬ ple :

- to have a standard structure with a stable and reli ^¬ able assembly,

- capacity for adapting in an efficient manner to the tolerances of the parts that are assembled,

- to be able to integrate mounting parts and functional parts (for example parts that come into play in the mecha ^¬ nisms of an optical, electrical and thermal nature associated with the operation of the device) ; and

- easy assembly/disassembly of the source of light ra ^¬ diation (for example using LEDs) .

In the prior art, a wide range of non-integrated solutions is known, which often require electrical/mechanical connections that are rather complex and the use of additional compo ^¬ nents/processes (for example cables, connections of various types, screws, additional mechanical fixing structures) likely to combine against the flexibility of the assem- bly/disassembly operations and to reduce the total perform ^¬ ance owing to a rather unsatisfactory integration between different components.

In particular, complex and bulky solutions are known that are relatively incompatible with the characteristics of compact ^¬ ness of the light sources such as LED light sources, in par ^¬ ticular as regards the possibility, offered by such light sources, of reducing the complexity and of increasing the ef ^¬ ficiency of the lighting system.

Purpose and summary of the invention

The aim of the present invention is to provide a solution to the requirements listed above.

According to the invention, such an objective is achieved thanks to a lighting device having the features claimed in the claims that follow. The claims form an integral part of the technical teaching presented here in relation to the invention.

Various embodiments allow at least one of the following ad ^¬ vantages to be gained:

- each of the surfaces of the lighting device, for exam ^¬ ple using LEDs, is dedicated to a specific technical function in such a manner as to optimize the efficiency in terms of performance,

- it is possible to achieve a high level of flexibility in relation to the assembly and to the disassembly of the source of light radiation (for example an LED source) even to the end of the useful life of the same;

- the availability of dedicated lateral surfaces allows such surfaces to be used for the electrical power supply function and/or for different communication functions (for example for the transmission of control signals for the light source) using one or more contact lines;

- it is possible to produce a reliable standardized cou- pling system in which the electrical connection functions, the optical functions and the heat dissipation function are uncoupled from one another.

Brief description of the figures

The invention will now be described, purely by way of non- limiting example, with reference to the appended figures, in which :

- figure 1 is a general perspective view of one embodi- ment,

- figures 2 and 3 illustrate the principles of operation of embodiments, and

- figures 4 and 5 are cross-sectional views approxi ^¬ mately corresponding to cross-sectional views along the line IV-IV in figure 1 which highlight features of embodiments.

Detailed description

In the following description, various specific details are illustrated aimed at a deeper understanding of the embodi ^¬ ments. The embodiments can be implemented without one or more of the specific details, or with other methods, components, materials, etc. In other cases, known structures, materials or operations are not shown or described in detail in order to avoid obscuring various aspects of the embodiments.

The reference to "one embodiment" in the scope of this de ^¬ scription is to indicate that a particular configuration, structure or feature described in relation to the embodiment is comprised within at least one embodiment. Thus, phrases such as "in one embodiment", potentially appearing in various places in this description, do not necessarily refer to the same embodiment. Furthermore, particular configurations, structures or features can be combined in any appropriate manner in one or more embodiments.

The references used here are only for convenience and do not therefore define the scope of protection or the range of ap- plication of the embodiments.

In the figures, the reference number 10 indicates a complete lighting device. In various embodiments, the device 10 can use, as a source of light radiation, one or more LED radiation sources indicated by 12.

In various embodiments, the source of light radiation 12 can be mounted on a respective board 14 for example taking the form of a printed circuit board (PCB) on which can be assembled circuit elements 16 which may comprise spring contacts 160a capable of deriving the electrical supply power for the radiation source 12 from a line (rail) 162 mounted on the housing of the device 10, potentially including con ^¬ trol/processing circuitry (for example a microcontroller) 164 capable of receiving and/or of exchanging signals with respect to the external environment of the device (for example, control signals or feedback signals on the operation of the device 10) via contacts 160b cooperating with one or more lines (rails) 166 installed on the housing of the device 10.

In the exemplary embodiments considered here, the source of light radiation 12 is mounted on a first face 14a of the board 14 turned (upward, in the orientation of the figures) in the direction of the opening part of the housing of the device 10 which, in the examples considered here, can have the general configuration of a channel.

A reflector and/or diffuser element 18 (for example made of molded transparent plastic material, potentially colored) , designed to project the light radiation produced by the source 12 toward the outside of the device 10, is installed in this opening part.

In particular, in the exemplary embodiment considered here (which is just that, and thus should not be interpreted in a sense which limits the embodiments) the body 18 has, if ob- served in transverse cross section (see figures 4 and 5) , a generally divergent form starting from the light source 12 with :

- an external face 18a exhibiting a general tile-shaped curvature with the convex surface turned toward the outside of the device 10, and

- an internal face 18b similarly curved in a tile shape, with the concave surface turned (downward, according to the point of observation of the figures) toward the bottom side of the housing of the device 10, hence toward the source 12, which in the exemplary embodiments considered here is com ^¬ posed of a linear array of LED sources.

In various embodiments, both the faces 18a and 18b of the body 18 can ideally describe corresponding substantially cy- lindrical surfaces centered around the axis of extension of the linear array of the sources 12.

In various embodiments, the board 14 can be applied in con- tact, for example in extended surface contact, via its second face 14b, with the base side of the housing of the device 10.

In various embodiments, the device 10 can be designed to ac ^¬ commodate an electrically powered light radiation source ca- pable of generating heat during operation (precisely as does an LED light radiation source) and has a general box shape, for example approximately a parallelepiped with the upper surface 18a curved in a tile shape, comprising several sides amongst which may be identified (as may be observed in fig- ures 1, 4 and 5 in coordination with figures 2 and 3) :

- a first face A (identified, in the exemplary embodi ^¬ ments illustrated here, as the external surface 18a of the reflector/diffuser element 18 associated with the source 12) forming an optical interface through which the light radia- tion is emitted from the device 10,

- a second face B (identified, in the exemplary embodi ^¬ ment considered here, as the base side of the housing) form ^¬ ing a thermal interface through which the heat generated by the light radiation source 12 can be dissipated to the out- side of the device, for example, toward a heat dissipater not specifically shown in the drawings,

- at least one third face C (identified, in the exem ^¬ plary embodiment considered here, as the two opposing lateral faces of the channel-like configuration of the housing of the device 10, carrying electrical contacts such as for example the rails 162 and 166) forming an electrical interface for the distribution, toward the source 12, of the electrical power supply and for the possible transmission of signals re ^¬ ceived by/sent from the "intelligence" installed in the de- vice, for example in the form of a microcontroller 164.

In the exemplary embodiments considered here, the third face C (electrical interface) is divided into two in the form of the two opposing faces (as seen in figures 4 and 5 in coordi ^¬ nation with figure 3) of the housing of the device, with one of the faces (on the left in the view in figures 4 and 5) which performs the function of electrical interface for the electrical power supply for the sources 12 (rail 162), whereas the opposite face (on the right in the view in fig ^¬ ures 4 and 5) carries out the function of electrical inter ^¬ face for the signals relating to "the intelligence" of the device 10. In various embodiments, it is accordingly possible to sepa ^¬ rate the functions of optical, thermal and electrical inter ^¬ facing by assigning:

- the function of optical interface (emission of the light) to the surface A,

- the function of thermal interface to the surface B, and

- the function of electrical interface to the surface or to the surfaces C. In various embodiments, each surface of the device or module 10 can therefore be "specialized" in the performance of a particular function.

For example, the lateral electrical connection offers free space and a high level of flexibility for the interfacing of the wall surface with a wide range of functions for power supply and intelligent communication.

This is achieved without interfering with the optical inter- face A and the thermal interface B, which are themselves dedicated to their specific optical interface and thermal in ^¬ terface functions. Various embodiments therefore allow the production of a com ^¬ pact integrated system (for example using LED radiation sources as light radiation sources) capable of demonstrating a high level of reliability deriving from the fact that each of the light source functions is assigned to a different sur- face of the device, in an independent and completely dedi ^¬ cated manner.

In various embodiments, the choice - as electrical interfac ^¬ ing surface C - of one or both of the side walls can offer the advantage that, in various embodiments, the relevant di ^¬ mension of the housing (the vertical dimension according to the observation viewpoint of the figures) can be specifically designed according to the electrical power sup ^¬ ply/communications requirements.

In an analogous manner, the dimension of the thermal interface (face B, bottom face in the exemplary embodiment illus ^¬ trated here) for example allows a possible increase in the power of the light source 12 to be taken into account in co- ordination with the power supply/communications requirements associated with the electrical interface C.

For example, as regards the definition of the characteristics of the device 10, an increase in the power of the source of light radiation 12 which is not accompanied by an increase in the complexity of the electrical interface can be taken into account by increasing the size of the thermal interface B (for example by doubling the width of the housing) leaving the vertical dimension of the same unchanged. In a complementary fashion, an increase in the complexity and flexibility of the electrical interface which is not accompa ^¬ nied by an increase in the power of the source of light ra- diation 12 can be handled by increasing the corresponding dimension (vertical, in the figures) of the interface C leaving the dimensions of the thermal interface B unchanged, which dimensions may for example be minimized (hence optimized) , in a totally independent manner, by taking only the requirements of the heat dissipation into account.

In other words, the two electrical and thermal functions are rendered "orthogonal" and hence independent from one another. This allows, for example, in the presence of more devices 10 designed to cooperate together, the electrical connection to be made through the lateral faces C of the juxtaposed devices without affecting the other optical and thermal interfacing functions .

In an analogous manner, in the case in which an "upgrade" of the board 14 is carried out, it is possible to make the sub ^¬ stitution of the board of the module 10 leaving the other functions unchanged, for example the electrical connection functions when these do not get involved in the operation by the upgrade operation.

Of course, still keeping to the principle of the invention, the particulars of implementation and the embodiments may vary, even significantly, which embodiments are illustrated here purely by way of non-limiting example, without however straying from the scope of protection of the invention, this scope of protection being defined by the appended claims.