Patent Publication Number: US-10317028-B2

Title: Lighting device made up of lighting elements and striplight made up of a plurality of such lighting devices

Description:
The present invention relates to a lighting device made up of lighting elements and a supply circuit for powering said elements. 
     The present invention also relates to a striplight made up of a plurality of such lighting devices. 
     Such devices are generally known, especially those that use LEDs as lighting elements. LEDs provide powerful light considering the electric power they consume. Many applications require intense omnidirectional lighting, while LEDs instead provide highly directional light outputs. 
     The aim of the invention is to provide a lamp that benefits from the efficiency of LEDs and which lights in an omnidirectional manner, while making it possible to obtain high light intensity. 
     For this purpose, a device of the type mentioned in the preamble is characterised in that said elements are organised in at least one assembly of at least one lighting element. 
     According to one aspect of the invention, the device comprises a plurality of said assemblies arranged on at least one mounting board and arranged so as to provide lighting according to a predetermined coverage. 
     Thus, by increasing the number of assemblies guided in different directions, omnidirectional lighting or lighting having a given light coverage is obtained, as well as luminosity which can be stronger. 
     One interesting application of the invention is that which relates to lighting in car parks, which requires easy maintenance and installation. 
     For maintenance, the invention proposes a system for plugging in boards in order to facilitate the replacement thereof in the event of a fault. As regards ease of installation, the supply circuit is of a type controlled to adjust the supply voltage of the lighting elements by also compensating for possible voltage drops due to the length of the power cable intended for powering the striplight. Indeed, when dealing with a striplight comprising such devices, the accessible voltage at the end of the striplight is considerably lower than at the start. It should be noted that the power cable, preferably carrying a low voltage, does not require any precautions or authorisation for the installation of such a striplight. 
    
    
     
       The following description, supported by the appended drawings, all provided as a non-limiting example, will easily explain how the invention can be carried out. In the drawings: 
         FIG. 1  shows in perspective a lighting device in accordance with the invention, 
         FIG. 2  shows a board for assemblies of lighting elements that is suitable for a device according to the invention, 
         FIG. 3  shows how said boards of assemblies are plugged into light facets placed on the supporting plate of the device, 
         FIG. 4  shows how the protective dome of the device is arranged on the supporting plate, 
         FIG. 5  shows an arrangement of the supply elements of said device of the invention, 
         FIG. 6  shows a strip of lighting devices in accordance with the invention, 
         FIG. 7  shows strips in accordance with the invention for lighting a car park, 
         FIG. 8  shows an example of an embodiment of a lighting device in accordance with the invention, 
         FIG. 9  shows the transmission of images involving the device shown in  FIG. 8 , 
         FIG. 10  explains the connections of the device shown in  FIG. 8 . 
     
    
    
     In these figures, the common elements all have the same references in all the figures. 
     In  FIG. 1 , the lighting device shown is made up of a circular base  5 , for example. The end of a threaded rod  7  is secured to the centre of this base. A supporting plate  10  with said threaded rod  7  passing through same is secured at a certain distance from the base  5 . This distance is determined by a nut, not shown, which blocks the vertical movement of this supporting plate  10 . Light facets F 1 , F 2 , F 3 , F 4  and F 5  are arranged on said supporting plate. Mounting boards are secured to said facets, some of which (PS 1 , PS 2 , etc.) are only referenced in the figure in order to avoid crowding it. An assembly E 1  of lighting elements L 1  to L 20  is placed on each of these boards, as shown in  FIG. 2 . The positioning of the facets and even of said boards makes it possible to adjust the direction and spatial distribution of the light beams. 
       FIG. 3  shows that the mounting boards PS 1  are removable with a view to facilitate the replacement thereof. For this purpose, connectors C 1 , C 2 , C 3 , etc. secured to the boards PS 1  are provided on said boards and engage with sockets P 1 , P 2 , P 3  respectively arranged on the light facets (F 1 , etc.). 
     The lighting device comprises a protective dome made of transparent material such as polymethyl methacrylate, better known by its commercial name of “Plexiglas”. This dome  20  is provided with a semi-spherical shape, and its base rests on the supporting plate  10 . Lugs  25 ,  26 ,  27 , . . . ,  31  are provided in order to centre said dome, as shown in  FIG. 4 . These lugs are arranged at the periphery of the supporting plate  10 . A hole  40  at the top of this dome allows the threaded rod  7  to be pass through same. Another hole  61 , visible in  FIG. 4 , is made in the supporting plate  10  for passing a cable  63 . A nut  43  holds said dome  20  against the supporting plate  10 . 
     A supply circuit  60  is placed under the light facets F 1  to F 5 . Said circuit is connected to the power cable  63  which passes through the hole  61 . Said circuit is made up of a transformer  65 , control electronics  67  and an accumulator system  69 . The transformer is of a controlled type which provides, in particular for lighting, a predetermined voltage for a voltage range which is applied at the input thereof. The accumulator  69  preserves the lighting during a power cut and can also supply a backup voltage to at least one lighting element. 
     The mounting of the device of the invention by means of a threaded rod allows for easy removal which, associated with the possibility of easily changing the mounting boards (PS 1  etc.) allows for very easy maintenance of said device. 
     Advantageously, the devices of the invention are well suited to a strip configuration. The invention makes it possible to play with the distribution of light by tilting the various facets (F 1 , F 2 , etc.) in order to obtain the required distribution or coverage of each device. Moreover, the voltage control provided by the controlled transformers makes it possible to obtain long-span striplights without any deterioration of the light intensity at the end of the line.  FIG. 6  shows the structure of such a striplight, which is made up of a plurality of devices in accordance with the invention  100 ,  101 ,  102 ,  103 , which are all connected to a power cable  63 . 
     One field of application of such a striplight is the lighting of a car park. This is shown in  FIG. 7 . The car park is made up of two rows: a first row for vehicles V 1 , V 2 , . . . , V 5  and a second row for vehicles V 11 , V 12 , . . . , V 15 . A striplight is assigned to each of these rows. A first striplight is assigned to the first row and is made up of lighting devices  111 ,  112 ,  113 ,  114  and  115 . These devices are powered by the cable  63 . A second row is illuminated by the lighting devices  121 ,  122 ,  123 ,  124  and  125 . They are powered via a power cable  63 ′. It should be noted that since such striplights can have a low voltage value, these lamps do pose any danger during crashes with manoeuvring vehicles. 
     Another example of a use of the invention is shown in  FIG. 8 . In this example, the lamp is attached to the ceiling of a room and a video camera  210  has been inserted for surveillance of this room. The lens of this camera is flush with the outside of the facet F 5 , as shown in  FIG. 9 . Its arrangement is such that it makes it possible to view objects according to an angle α which is as large as possible, and it is recessed enough to avoid the glare from the surrounding LEDs. 
     This camera  215  is connected to a PLC device  217  (device for coupling by powerline communication) which makes it possible to transmit a supply current and data over a single line, and thus to transmit the images captured by the camera  215  to a surveillance centre  300  in order to be viewed on a screen  310 . The images can be accessed in the surveillance centre  300  by another PLC device  317 , by travelling through the cable  63 . Reference  330  indicates a power source for at least one lamp. The surveillance centre  300  can be provided with various PLC devices  320 ,  321 , etc., assigned to various cameras which are part of various lamps. 
       FIG. 10  shows that, just like in  FIG. 5 , the various elements, including the coupling device  217 , are placed under the light facets F 1 , . . . , F 5 . 
     The lighting device can also be used in the context of lighting a room such as an office or a meeting room. It is possible to attach a strong Wi-Fi booster of the type used in this type of room to the base  5  of the lamp. This is indicated by reference  350 . This allows the participants meeting in the work room to connect easily to the Wi-Fi network.