BAR PROVIDED WITH LED LIGHT
DESCRIPTION
The present invention relates to a bar of lights, of a type comprising a light source fitted with a plurality of LEDs (Light Emitting Diodes), a structure adapted for housing said light source and having a side open to allow the light beam generated by said light source to come out from said bar of lights, means adapted for controlling the operation of said light source, and means adapted for supplying said light source.
According to the state of the art, the known bars of lights comprising a light source fitted with a plurality of LEDs (Light Emitting Diodes) and that have an electronic circuit for controlling the operation of the light source, as well as a system for supplying said light source which are both located in a remote position with respect to the bar of lights. Such a solution has been adopted for fear that the heat produced by the light source, especially when equipment having many LEDs is concerned, may cause failures in the electronic control circuit.
This problem virtually prevents from integrating any electronic components, which need to be adequately cooled, within the structure of bars of lights. At present, therefore, for each bar of lights unit used it is necessary to employ a specific power supply system and a specific operation control unit, both of which are located in a remote position with respect to each unit of said bars of lights.
This means that, in order to realize a lighting system, it is necessary to adopt a complex system of connection cables, both for controlling and supplying every single bar of lights; this makes the production and maintenance of a system made up of a plurality of bars of lights very complex and expensive.
In fact, if on one hand the system requires cables to carry the electric current required for the operation of the equipment, on the other hand it also requires additional cables to exchange information necessary to allow the electronic circuits to control the operation of the bar of lights and therefore be able to control the different functions of the light source.
This multiplicity of cables is often subject to the action of atmospheric agents, which may cause its deterioration (in particular given the fact that generally these are not cables having a thick insulating sheath), resulting in interference with the exchange of information between
the bar of lights and the control and supply system.
The presence of external connection cables between the light source and the circuit controlling its operation may also involve either the necessity of using shielded cables, which are expensive and not very flexible, thus being difficult to lay, or, if unshielded cables are used, the risk that these may pick up external interference affecting the reliability of the system controlling the operation of the bars of lights.
Furthermore, in many instances the existence of external cables (in addition to the supply cables), when cables are to be physically laid in places of difficult access (in that bars of lights may be installed in places being very dangerous to reach for technicians, such as, for example, on high or poorly maintained buildings), on one hand would make the installation more complex and on the other hand would produce an aesthetically poor result (in particular for indoor lighting applications).
According to the state of the art, many lighting systems are also known which use a plurality of bars of lights positioned in sequence; let us consider, for example, the lighting systems inside tunnels, where many bars of lights, generally consisting of fluorescent lamps (of the type known as "neon lamps"), are installed in sequence.
Each of said bars of lights is connected to the supply system and is positioned at a certain distance from the previous and the subsequent bars of lights. Such systems therefore have the drawback of not permitting an evenly distribution of light of the adjacent areas; as a matter of fact, in the area between the end of a bar of lights and the beginning of the next one, the lighting of the surrounding environment will necessarily be attenuated, resulting in areas more illuminated followed by areas less illuminated. Moreover, also in these cases a plurality of cables is needed both for carrying the electric current required for the operation of every bar of lights and for exchanging information to allow any electronic circuits present on each bar of lights to control their operation.
According to the state of the art, other bars of lights are also known which use a light source consisting of a plurality of LEDs replacing the conventional neon tubes, in order to exploit the characteristics which are typical of LEDs; in fact, neon lamps are fragile, polluting, drain a lot of electric current and emit a monochromatic light beam, whereas LEDs last longer, drain less electric current, do not pollute the environment and permit to obtain a light beam having different colours.
Said bars of lights having a light source consisting of a plurality of LEDs use a device, located in the area of the open lateral portion of the bars of lights structure and made of an opaque material, which is adapted for reflecting and refracting the light produced by said plurality of LEDs in order to shed said light and consequently evenly distribute the light beam produced by the plurality of LEDs.
Said devices, being made of an opaque material, are also used for hiding the punctiform light source consisting of the various LEDs used, so that the bars of lights looks like a common neon tube. Using such devices has the drawback of attenuating the intensity of the light beam produced by the plurality of LEDs; this drawback is particularly important, for instance, in outdoor lighting applications, where it is necessary to have a light beam available with an intensity such as to allow illumination of wide areas or entire fronts of buildings. Moreover, such diffusing devices increase the external dimensions of the bars of lights. Finally, in the event that said bars of lights use a plurality of coloured LEDs, the presence of said devices made of an opaque material will not allow to obtain a light beam having the desired colour.
In this frame, the main aim of the present invention is to provide a bars of lights manufactured in such a way as to incorporate the electronic parts within its structure through means adapted for preventing the internal components of said bars of lights from being overheated. A further aim of the present invention is to provide a bars of lights manufactured in such a way to allow its connection to the adjacent bars of lights without the need of using cables for carrying electric current and exchanging information.
A further aim of the present invention is to provide a bars of lights manufactured in such a way to be able to evenly illuminate the areas surrounding the lighting system, consisting of a plurality of interconnected bars of lights.
A further aim of the present invention is to provide a bars of lights which is able to produce an evenly distributed light beam without the need of positioning, in the area of the open side of the bars of lights structure, any devices adapted for evenly distributing the light beam produced by the plurality of LEDs and for hiding the light source consisting of said plurality of LEDs.
In order to achieve such aims, it is the object of the present invention to provide a bars of
lights incorporating the features of the annexed claims, which form an integral part of the present description.
Further objects, features and advantages of the present invention will become apparent from the following detailed description and annexed drawings, which are supplied by way of non- limiting example, wherein:
- Fig. 1 shows a perspective view of a bars of lights incorporating the features of the present invention;
- Fig. 2 shows an exploded perspective view of the bars of lights incorporating the features of the present invention; - Fig. 3 shows a section side view of the internal parts of a bars of lights incorporating the features of the present invention;
- Fig. 4a shows a side view of two interconnected bars of lights incorporating the features of the present invention;
- Fig. 4b shows a perspective view of a first bars of lights and of the means for interconnecting a plurality of bars of lights incorporating the features of the present invention;
- Fig. 4c shows a perspective view of a second bars of lights and of the means for interconnecting a plurality of bars of lights incorporating the features of the present invention. As to the description of the drawings, Fig. 1 and Fig. 2 show a bars of lights 1 incorporating the features of the present invention; it comprises a structure 2 and a light source 3, consisting of a plurality of LEDs 4.
Said structure 2 comprises inside of it a plate 8 which allows the exact positioning of said plurality of LEDs 4 as well as the electric (supply) and the electronic (control) connection of each LED 4. Said plurality of LEDs 4 has an arrangement which is substantially linear (i.e. the LEDs 4 are positioned one next to the other), and the light it produces creates a light beam which may have either a diverging or a constant section as necessary, and which comes out of said bars of lights 1 through an open lateral portion 5 of the structure 2 of said bars of lights 1 ; the shape of the light beam section substantially depends on the shape of the reflector surrounding each LED 4. In a preferred embodiment of the present invention, the reflector surrounding each LED 4 consists of a collimator 6; through an appropriate arrangement of each LED 4 on said plate 8
and the use of a collimator 6 associated with each LED 4, the light beam produced by each LED 4 is correctly mixed with the light beams produced by the other LEDs 4, and the resulting light beam has a substantially evenly distributed basic colour, without the need of installing any devices adapted for shedding and evenly distributing the light produced by the plurality of LEDs 4 in the area of the open lateral portion 5 of the structure 2 of the bars of lights 1.
The shape of the section of said light beam may also be further modified by using a substantially flat transparent surface 7, positioned in the area of said open lateral portion 5; for instance, said transparent surface 7 may consist of flat lenses, convex lenses, "frost" lenses, etc., so that the light beam may be adapted to each specific application of the bars of light 1. Said plurality of LEDs 4 is preferably composed of Red, Blue and Green LEDs 4, so as to provide, under the management of the control circuit, all colour shades; in fact, such basic colours of the LEDs 4 may be combined in many ways to generate the whole range of colours that can be perceived by the human eye. It is also possible to add LEDs 4 having a different basic colour, preferably Amber; said Amber-coloured LEDs 4 offer the possibility to further modify (in the sense of adjusting) said range of colours emitted by the bars of lights 1 which is the object of the present invention. A further possibility offered by the combination of the above-mentioned primary colours, with the addition of said Amber-coloured LEDs 4, consists in providing one or more corrections for changing the colour temperature, which allows the elimination certain colour temperature gradations before the resulting light beam comes out from said open lateral portion 5 of the structure 2 of said bars of lights 1.
In this way, it is possible to obtain light beams with a different colour temperature, adapted for different service conditions: outdoor lighting, indoor lighting, and so on. As it can be seen in more detail in Fig. 3, which shows a sectional side view of the bars of lights 1, under the plate 8 there is a heatsink 9 having an array of blades 10. Said heatsink 9 is in thermal contact with the plate 8 on which said plurality of LEDs 4 is located, and allows the dissipation of the heat produced by said plurality of LEDs 4 through the surface of said array of blades 10, which in turn are in contact with the structure 2 also acting as a heatsink, thus avoiding that the heat may increase the temperature within the structure 2 up to values which may cause damage to the electronic circuits 12 within the bars of lights 1.
In addition, on the structure 2 it is possible to provide some openings on the side opposite to the open lateral portion 5, which are not in view when the bars of lights 1 are mounted, and which contribute to cool the area where the electronic components are installed.
Further arrays of blades 14 may be provided on the structure 2 of the bars of lights 1 in order to further dissipate the heat produced by the light source 3 made up of the plurality of LEDs 4.
Under the heatsink 9 there is a plate 11; said plate 11 houses all of the electronic circuits 12 and electric components 13 which are necessary for the proper operation of the bars of lights
1.
In particular, said electronic circuits 12 and said electric components 13 are mounted in such a way to be shielded from the heat produced by said plurality of LEDs 4; in fact, they are turned in the opposite direction with respect to the direction of insertion of the LEDs 4 on the plate 8, thus allowing the heatsink 9 to act as a thermal shield against the heat generated by the plurality of LEDs 4.
It can therefore be understood how, thanks to the measures described above, it is possible to integrate the electronic control circuits 12 within the structure 2 of the bars of lights 1.
In particular, the surface of said plate 11 is adapted for housing a plurality of power supplies and a microprocessor controlling the current supplied to the single LEDs 4 by said plurality of power supplies.
In a preferred embodiment of the present invention, each power supply supplies a plurality of LEDs 4 having the same colour.
Other traditional components may also be installed onto the plate 11, such as capacitors, resistors and coils.
In a further preferred embodiment, said power supplies are of the switching type and have a
"cold" operation, i.e. dissipate little control current; this allows to optimize the consumption of mains voltage, as none of the components housed on the plate 11 has any considerable efficiency losses which may affect their operation. The switching-type power supplies control the current supplied to the LEDs 4, so that it is possible to adjust the brightness by modulating the output current of said power supplies.
The microprocessor may be of the type known as Flash; it controls the current generated by the power supplies so as to vary the characteristics of the light beam produced by the LEDs 4, for example in terms of intensity control, colour and colour temperature, and allows to control
functions which create special effects known as Strobo, Sincro and Delay. In a preferred embodiment, the microprocessor uses the PWM (Pulse- Width Modulation) technique for controlling the output current of the power supplies; said microprocessor can also receive signals, for instance through DMX (Digital Multiplex) or DALI (Digital Addressable Lighting Interface) communication protocols.
Another characteristic of said microprocessor consists in the possibility of being programmed in place or at the factory for having the bars of lights 1 perform particular "shows". The bars of lights 1 to which the present invention is directed is also fitted with connection means 15, 16, 17, 18, 19a, 20a, 19b, 20b manufactured in such a way to allow the interconnection of two or more bars of lights 1 through a "bayonet" type joint; in fact, each bars of lights 1 is provided with a first lid 15 on one end, and a second lid 16 on the other end. As it can be seen in Fig. 4b and Fig. 4c, the lid 15 comprises a male connector 17, adapted for being inserted into a female connector 18 incorporated in the lid 16 of a next bars of lights 1. Said male connector 17 and female connector 18 each have two pairs of electric contacts 19a, 19b and 20a, 20b; a first electric connection takes place between the pair of electric contacts 19a of the male connector 17 and the pair of electric contacts 20a of the female connector 18. Said pairs of electric contacts 19a, 20a are connected to the electric components 13 within the bars of lights 1 and are adapted for carrying the supply current from a bars of lights 1 to an adjacent bars of lights 1. A second electric connection takes place between the pair of electric contacts 19b of the male connector 17 and the pair of electric contacts 20b of the female connector 18; said pairs of electric contacts 19b, 20b are connected to the electronic circuits 12 within the bars of lights 1 and are adapted for carrying the service signals from a bars of lights 1 to an adjacent bars of lights 1. In this way, the male connector 17 and the female connector 18 allow to interconnect two or more bars of lights 1 without using additional cables.
Thanks to the particular design of said male connector 18 and female connector 17 of said lids 15 and 16, the electric current can be carried from the power source to the plurality of bars of lights 1 connected in line to one another. As a matter of fact, the connection of the first bars of lights 1 of a plurality of bars of lights 1 to the power source is sufficient for supplying also the subsequent bars of lights 1 , by simply
connecting the male connector 17 of the bars of lights 1 to the female connector 18 of the adjacent bars of lights 1.
The electronic circuits 12 of every bars of lights 1 are also interconnected by means of said male connector 17 and female connector 18 positioned on said lids 15 and 16; therefore, the microprocessors contained within each bars of lights 1 can communicate with one another.
Moreover, the microprocessor being present in every bars of lights 1 can be programmed, in place or at the factory, so as to be able to manage a certain plurality of bars of lights 1 for having said plurality of bars of lights 1 perform particular "shows".
In particular, the microprocessor contained within one of the bars of lights 1 could act as a "master" for controlling one or more "slave" bars of lights 1 equipped with a microprocessor for information exchange.
In such a situation, each "slave" bars of lights 1 would therefore be in a condition to use the information received from the "master" bars of lights 1 for activating its own functions (e.g. turning on and adjusting the intensity of the light supplied to the LEDs 4, checking the intensity and colour of the light beam, checking and changing the colour temperature of the light beam, execution of a particular show by the plurality of bars of lights 1, etc.).
The communication among the various microprocessors may take place in any known way according to the prior art; for instance, if a conveyed wave system is used, the information for changing the characteristics of the light beam produced by the LEDs 4 can be exchanged on the same electric supply line. In such a case, the presence of the electric contacts 19b and 20b on the male connector 17 and on the female connector 18 is no longer necessary.
The advantages of the present invention are apparent from the above description.
In particular, by using means 9, 10, 14 adapted for dissipating the heat produced by the light source 3 and by correctly positioning and shielding the components within the bars of lights 1 , as well as by providing appropriate vent openings, the heat produced by the light source 3 is adequately dissipated, thus eliminating any overheating problems affecting the electronic circuits 12 housed within the same structure 2.
The integration of the electronic circuits 12 and of the electric components 13 within the structure 2 of the bars of lights 1 allows to realize synchronized combinations of the LEDs 4 of said bars of lights 1 without needing a remote control unit to control said bars of lights 1.
The elimination of said remote control unit drastically reduces the wire harness needed for the
connection of each bars of lights 1, resulting in a reduction of the costs and realization times of the system, as well as of signal interference problems and maintenance difficulties. Another advantage of the present invention lies in the fact that the use of the connection means 15, 16, 17, 18, 19a, 20a, 19b, 20b and the integration of the electronic circuits 12 and of the electric components 13 within the structure 2 of the bars of lights 1 allow to connect each bars of lights 1 to one or more adjacent bars of lights 1 without the need to use a wire harness for carrying the electric current and for exchanging information, as well as to shed a evenly distributed light on the areas surrounding said bars of lights 1 , as the space between two adjacent bars of lights 1 is substantially null. A further advantage of the present invention consists in the fact that the light beam produced by every bars of lights 1 is evenly distributed through a correct positioning of the LEDs 4 and through the use of collimators 6 associated with each LED 4, without requiring further devices for evenly distributing the light beam produced by the plurality of LEDs 4 and for hiding the light source 3 made up of said plurality of LEDs 4. It can be easily understood that the present invention is not limited to the bars of lights described above with reference to its various components, but may be subject to many modifications, improvements, or replacements of equivalent parts and elements without departing from the novelty spirit of the inventive idea. One of the various possible modifications provides connection means 15, 16, 17, 18, 19a, 20a, 19b, 20b made in such a way to allow interconnection of a plurality of bars of lights 1 not only in a straight line, but also in such a way to form different angles between each bars of lights 1 and the next. To this end, the lids 15 and 16 may have a substantially pyramidal shape with appropriate opening angles, or be of the "bellows" type. Another possible modification consists in providing means adapted for facilitating the correct connection between the lid 15 on a bars of lights 1 and the lid 16 on an adjacent bars of lights 1 ; for example, said means may be one of the various known systems adapted for preventing an accidental wrong connection between the pairs of electric contacts 19a, 19b; 20a, 20b in the lids 15 and 16. One of these known means may consist in providing, in a lid 15, 16, a protrusion (key) to be coupled with a corresponding hole in the other lid 15, 16. A further possible modification consists in arranging the LEDs 4 according to a plurality of rows of LEDs 4, e.g. three rows, so that each of said rows of LEDs 4 has a substantially linear
arrangement.
It is clear that many other alternatives and applications of the bars of lights described herein by way of example are possible for those skilled in the art, as well as that in the practical realization of the invention the components may have shapes and dimensions different from those described or be replaced with other technically equivalent elements.