A subject of this invention is the lighting element, especially for suspended ceiling, designed to illuminate indoor space, specifically office and industrial spaces.

The structural bar of lighting element fixed to suspended ceiling, usually has a T-bar shape. T-bar arms mount the lighting fitting and the vertical part mounts the lighting element to the structure of suspended ceiling. Such a lighting element can be attached to the suspended ceiling in a similar way as the suspended ceiling structural components, it means, the main structural bars installed in parallel and connected with lateral bars. The lateral bars are usually provided with end links inserted and secured in suitable shaped slots made in the web of main bar. Such a solution is described, among others, in patent PL188085. Structural components of suspended ceilings fabricated by various manufacturers differ from each other with a shape of end links and thus a shape of slots made in the web of structural bars. To install the lighting element in the suspended ceiling grid it is required to previously prepare the ceiling bars to accommodate links of lighting element structural bar, or to tailor the links of lighting element structural bar to match the system of connecting bars of suspended ceiling made by a particular manufacturer. The structural bar of lighting element known from the description of application P.416816 has a T-bar shape, whose vertical element is specially ribbed and joined not permanently with a pair of holders which enable hanging the light on the main or lateral bar of suspended ceiling. Each of the known solutions described above requires to provide the lighting element with additions components which enable attaching the lighting element to the suspended ceiling structure.

The invention objective was the design of lightning element which can be easily attached to a steel structure of any type of suspended ceiling with no need to previously prepare in a special way the components to be assembled.

The lightning element, especially for suspended ceilings, in accordance with the invention, is made from structural bar in a form of flat bar, to which light sources and their protective bowl, made of translucent material, are attached with known methods. The light sources are connected in a known way to power supply. The essence of the invented solution is that the structural bar of lighting element incorporates at least one built-in permanent magnet whose resultant value of nominal magnetic attractive forces is at least twice higher than the weight of complete lighting element. This guarantees the effective and reliable attachment of lighting element to the suspended ceiling. A real value of magnetic attractive force depends on several factors, and above all, on the air or other insulation media between the magnet surface and the attracted surface, a type of material the attracted surface is made of, or temperature. The loss of magnetic properties of the permanent magnet along the duration of its service must be also taken into consideration. It is advantageous that the resultant value on nominal magnetic attractive forces is at least three times higher than the weight of complete lighting element.

It is advantageous that the used permanent magnet is a neodymium magnet, featuring small weight and size, and simultaneously producing a very strong magnetic field which gives a large attractive force.

It is advantageous that the used permanent magnet has a shape of flat disc or rectangular prism.

It is advantageous that the light source is a number of LEDs installed on a printed circuit board.

It is advantageous that the structural bar of lighting element is made of metal or plastic material.

The advantage of lighting element in accordance with this invention is the possibility to easily attach it to the suspended ceiling of any type whose primary structure is made of steel.

A subject of this invention is explained in more details on the examples of fabrication illustrated on the drawing in which fig.1 presents a view of lighting element with four magnets in the structural bar in the axonometric projection, fig. 2 presents the axonometric projection of lighting element in exploded view, fig. 3 presents the cross-section of lighting element along the A-A line in fig. 2, and fig. 4 presents the axonometric projection with one magnet of rectangular cross-section.

The lighting element Λ_ consists of aluminium structural bar 2, which mounts, in a known way, a printed circuit board 3 and LEDs 4 being light sources of the lighting element A and bowl 5, protecting the light sources, made of translucent material. The structural bar 2 of lighting element λ has a form of flat bar in which four permanent magnets 6 in a form of flat discs are built in. The magnets 6 are located in seats made in the lower surface of the structural bar 2, matching in terms of shape and size the magnets, so that the lower surfaces of the magnets 6 and the lower surface of structural bar 2 are flushed. A bottom of each seat is provided with a concentric hole 7 having a diameter smaller than that of the seat. The input of printed circuit board 3 is connected to a power lead 8, via the cable clamp 9. The power lead 8 of lighting element 1 is routed out through the holes VQ in the ceiling structural bar 11 to the space above the grid of suspended ceiling and connected to the power supply located there. The cable clamp 9 is located next to the place where the structural bar 2 is connected to the bowl 5, which allows for making hole 10 in the ceiling structural bar J in convenient places that will not weaken its strength. Spaces between the structural bar 2 and the bowl 5 are stopped with caps 12. The weight of complete lighting element described in this fabrication example is approximately 150 g, and the nominal attractive force of the magnets used is 2.9 N.

In the other fabrication example, the structural bar 2 of lighting element Λ is provided with one magnet ( , having a shape of rectangular plate, is installed in the centre of structural bar 2. The weight of complete lighting element described in this fabrication example is approximately 150 g, and the nominal attractive force of the magnet is 2 N.