SE544746C2 - Light fitting device - Google Patents

Abstract

A light fitting device (200), for removable attachment of a lighting body (20) to a rail of a functional ceiling. The light fitting device (200) comprises a power connector (210) for receiving a primary power (15), a lighting body connector (220) for receiving the lighting body (20), a ceiling attachment means (230) and an electronic power converting circuitry (240). Wherein the primary power connector (210) is operatively connected to the lighting body connector (220) by means of the electronic power converting circuitry (240). The electronic power converting circuitry (240) is configurable to convert the primary power (15) to a secondary power (25) and provide the secondary power (25) to the lighting body connector (220).

Description

TECHNICAL FIELD The present invention relates to light f1tting devices and more particularly to a light fitting device for removable attachment of a lighting body to a functional grid ceiling.

BACKGROUND Indoor lighting is something that is of great importance in virtually all indoor environments. Correct lighting in an office will decrease employee fatigue and sick leave. In a retail facility, correct lighting will increase the shopping experience and creative lighting can help with product promotion and increase sales.

In commercial buildings, lighting is commonly provided via a structure known as for instance a functional grid ceiling, functional ceiling system or system ceiling. These ceilings are typically comprised of horizontal rails fastened to an upper parts of the walls or the ceiling of a structure. These rails can support e.g. electrical wiring or acoustic ceilings. Some functional grid ceilings comprise a power track system in which a standardized system to distribute power is part of the functional grid ceiling. The power distribution may be in form of three circuit track system such as the widely used 3-phase DALI track system. These three circuit track systems provide power in three phases via the rails of the functional ceiling and allows the mounting of lighting fixtures across the functional ceiling. These lighting fixtures are available in various shapes and are attachable to the power distribution system of the functional grid ceiling. Some lighting sources, e. g. LED or halogen light sources, may require a power configuration different from that provided by the power distribution system of the functional grid ceiling.

One way to provide the required power configuration, is by incorporating the power conversion circuitry in the lighting fixture or the light bulb, as is the case in many E27 LED bulbs on the market. These solutions are bulky and reduce the design flexibility of the lighting fixture.

An alternative way is presented in EP 3495 726, wherein a guide provides power to a lighting apparatus. The guide is powered by a power-supply apparatus that can perforrn a transforrnation from 220 VAC at 48 VDC.

Having the entire power distribution system of the functional grid ceiling to provide a power that differs from a typical mains power reduces flexibility in the selection of light sources.

The prior art lacks a lighting solution that is flexible in the choice of light source, easy to move about across the functional grid ceiling and that is easy to install.

From the above, it is understood that there is room for improvements.

SUMMARY An object of the present invention is to provide a light f1tting device which eliminates or at least mitigates the drawbacks discussed above. This object is achieved by the technique set forth in the appended independent claims with preferred embodiments defined in the dependent claims related thereto.

In a first aspect, a light f1tting device for removable attachment of a lighting body to a rail of a functional ceiling is presented. The light f1tting device comprises a power connector for receiving a primary power, a lighting body connector for receiving the lighting body, a ceiling attachment means, and an electronic power converting circuitry. The primary power connector is operatively connected to the lighting body connector by means of the electronic power converting circuitry. The electronic power converting circuitry is configurable to convert the primary power to a secondary power and provide the secondary power to the lighting body connector. Besides mitigating at least the abovementioned drawbacks, this aspect provides a light f1tting device that is possible to use with a plurality of lighting bodies.

In one embodiment of the light f1tting device, the ceiling attachment means comprises at least one magnet for removable attachment of the light f1tting device onto a functional ceiling having ferromagnetic properties. This makes it possible to freely move the light f1tting device, and consequently the lighting body, across the functional ceiling without the use of tool or undue work.

In a further embodiment of the light fitting device, the ceiling attachment means comprises a plurality of magnets facing in both a sideways direction and in an upward direction for removable attachment of the light fitting device onto a functional ceiling having ferromagnetic properties. Having magnets facing different directions allows for a stable attachment of the light fitting device to the functional ceiling regardless of how the mass of the lighting body and the light fixture is distributed.

In another further embodiment of the light fitting device, the ceiling attachment means is arranged such that the light fitting device can be removably attached to the functional ceiling in the upward direction towards the functional ceiling. This is beneficial since it allows the lighting to be adjusted, removed, or expanded in a convenient and safe manner.

In another embodiment of the light fitting device, the secondary power is different from the primary power in that at least one of a secondary voltage, periodicity or current of said secondary power differs from a respective primary voltage, periodicity or current. This is beneficial since it enables lighting bodies requiring a power that is different from the primary power to be used with the light fitting device.

In yet another embodiment of the light fitting device, the electronic power converting circuitry comprises a controller configured to control at least one of the secondary voltage, periodicity or current. Having a controller comprised in the electronic power converting circuitry allows for design freedom in the secondary power and accurate control of the secondary power.

In one embodiment of the light fitting device, the electronic power converting circuitry is configurable to provide the secondary power at one of a plurality of different power configurations. This is beneficial since it allows the same light fitting device to be used with lighting bodies requiring different secondary power.

In an additional embodiment of the light fitting device, at least two power configurations of the plurality of different power configurations differ in the voltage, periodicity and/or current. This is beneficial since it allows the same light fitting device to be used with lighting bodies requiring different secondary power.

In one additional embodiment of the light fitting device, it comprises one or more selectors operatively connected to the electronic power converting circuitry for selecting one of the plurality of different power configurations. This is benef1cial since it enables the desired secondary power to be selected by simple operation of the switches.

In yet one additional embodiment of the light f1tting device, the electronic power converting circuitry comprises a wireless communication module for wirelessly receiving control data. The control data comprise control commands for controlling at least one of the secondary voltage, periodicity or current. This is beneficial since it allows for wireless control of the lighting.

In one embodiment of the light f1tting device, it comprises a housing of a material that is an electrical insulator. This is benef1cial since it may remove requirements for e. g. protective grounding in the primary power connector.

In a further embodiment of the light fitting device, the power connector is a connector without protective grounding. This is beneficial since connectors comprising fewer contacts are typically cheaper and smaller allowing for reduced size and cost of the light fitting device.

In one embodiment of the light f1tting device, the lighting body connector is arranged to provide mechanical support for a lighting body connected to the lighting body connector. This is beneficial since it enables the lighting body connector to be both attached to the functional ceiling and powered by means of the light fitting device.

In yet another embodiment of the light f1tting, the lighting body connector is formed with a radial cut out adapted to receive a mating lighting body connector of the lighting body such that the lighting body can be rotated about a center axis of an interface shaft of the lighting body. This is benef1cial since it allows the direction of the light provided by the lighting body to be easily controlled by rotation of the lighting body.

In another embodiment of the light f1tting device, the primary power is provided from a mains power. This is beneficial since mains power is typically readily available and accessible.

In a further embodiment of the light f1tting device, the primary power is an altemating current, AC, power and the secondary power is a direct current, DC, power.

This is benef1cial since DC is preferred when using e. g. LED lighting bodies.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will be described in the following; references being made to the appended diagrammatical drawings which illustrate non-limiting examples of how the inventive concept can be reduced into practice.

Fig. la is a perspective view of a room with a functional ceiling.

Fig. lb is a perspective view of a lighting fixture.

Fig. 2 is a schematically block illustration of a light f1tting device according to some embodiments of the invention.

Fig. 3 is a schematically shown block illustration of an electronic power converting circuitry according to some embodiments of the invention.

Fig. 4 is a schematically shown block illustration of an electronic power converting circuitry according to some embodiments of the invention.

Fig. 5a is a perspective view of a light fitting device according to some embodiments of the invention.

Fig. 5b is a bottom view of a light f1tting device according to some embodiments of the invention.

Fig. 6a is a perspective view of a lighting body connector according to some embodiments of the invention.

Fig. 6b is a top view of a lighting body connector according to some embodiments of the invention.

Fig. 6c is a top view of a lighting body connector according to some embodiments of the invention.

Fig. 7 is a perspective view of a light fitting device according to some embodiments of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS Hereinafter, certain embodiments will be described more fially with reference to the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention, such as it is defined in the appended claims, to those skilled in the art.

Throughout this disclosure certain terrns are used, these terrns should not be regarded as limited to their literal meaning, but rather considered descriptive and interpreted from their functional meaning. The term functional grid ceiling or functional ceiling is to mean a functional ceiling in that it perforrns additional functions, e.g. provide power, support or damping acoustic properties, to those of a normal ceiling. Further to this, the reference to rail or horizontal rail is to mean a constructional piece that may also be described as a beam or a shaft. A non-limiting example of a functional ceiling l0 is presented in Fig. la. The functional ceiling l0 comprises one or more rails ll arranged to support and provide power to one or more lighting fixtures l The term lighting fixture l00 is, for the purpose of this disclosure, meant to encompass an apparatus comprising a f1tting for lighting ll0 and a body for lighting l20. One such lighting fixture l00 is depicted in Fig. lb, wherein the f1tting for lighting ll0 comprises a power interface l 15 for receiving power through the functional ceiling l0. A prior art lighting fixture l00 may comprise a fitting for lighting ll0 adapted to receive power through a rail ll comprising a three circuit track system such as the widely used 3-phase DALI track system. In the 3-phase DALI track system, the power interface l 15 is used both as a means to provide power to the body for lighting 120, and also to provide mechanical support for the lighting fixture l00. This is achieved by forrning the rails ll of the functional ceiling l0 in a downwardly open U-shape, where the fitting for lighting ll0 is adapted to be received in the U-shaped rail ll.

As mentioned in the background section of this disclosure, there are drawbacks with the lighting fixture l00 shown in Fig. lb. The inventors behind this disclosure have, during their inventive processes, identified further shortcomings with the prior art. The lighting fixture l00 shown in Fig. lb requires a functional ceiling l0 compatible with the power interface l 15 of the fitting for lighting ll0. As a result, if a functional ceiling l0 is not compatible with the provided power interface l 15, major modifications to the functional ceiling l0 are required. These modifications may incur costs in material and labor, but also losses in business due to substantive refurbishments requiring temporary closure of facilities. Further to this, the body for lighting l20 is typically pivotally and/or rotatable attached to the fitting for lighting 110. This means that if the body for lighting 120 is provided with a power Conversion circuitry, the size and weight of the fitting for lighting 110 will be increased due to added components. This in turn, will add stress to the f1tting for lighting 110 especially through increased torque when the body for lighting 120 is pivotally and/or rotatable attached to the f1tting for lighting 1 The inventors behind this disclosure have, through inventive thinking, realized that many of the drawbacks mentioned above are removed, or at least reduced, by a novel and inventive light f1tting device 200. Fig. 2 illustrates one embodiment of the light fitting device 200. The light fitting device 200 may be a stand-alone device 200 comprising a power connector 210 and a lighting body connector 220. The light f1tting device 200 is configured to receive primary power 15 at the power connector 210. The light fitting device 200 further comprises an electronic power converting circuitry 240 configured to convert the primary power 15 to a secondary power 25. The light fitting device 200 also comprises a lighting body connector 220 and the electronic power converting circuitry 240 is configured to provide the secondary power 25 to the lighting body connector 220. The lighting body connector 220 is a connector 220 configured to provide both an electrical interface together with a mechanical interface to a lighting body 20. The lighting body connector 220 will be exemplified in coming sections. The light f1tting device 200 further comprises a ceiling attachment means 230 adapted to attach the light f1tting device 200 to the functional ceiling 10. The ceiling attachment means 230 is formed such that the light f1tting device 200 may be attached to a functional ceiling 10 in a manner such that it can be mounted, removed or moved along the functional ceiling 10 without the use of tools. The ceiling attachment means 230 will be explained in more details in the coming sections. The light fitting device 200 may be enclosed in a housing 250, this will be explained in more detail in coming sections with reference to Figs. 5a-b.

The light f1tting device 200 of Fig. 2 enables any lighting body 20 compatible with the lighting body connector 220 to be connected to the light fitting device 200 regardless of the power requirements of the lighting body 20. This enables freedom when designing the lighting body 20. Since the power converting circuitry 240 is comprised in the light f1tting device 200, the lighting body 20 may be designed without the power converting circuitry 240. This means that the size and cost of the lighting body 20 can be reduced. Also, the same light fitting device 200 may be used with different lighting bodies 20 which makes it cheap and efficient to change lighting for e. g. special promotions, holidays etc. By simply replacing the lighting body 20, a completely new look and design of the lighting of a location may be achieved and the light fitting device 200 enables this in a flexible and cost effective manner. Such a re- design of the lighting of a location would, with previous solutions, have generated significant amounts of used material that in many cases would have ended up in the junk yard. Since the light f1tting device 200 is reused, the amount of material to discard is reduced and the environmental impact is significantly lower compared to previous solutions.

With reference to Fig. 3, the power converting circuitry 240 will be explained in more detail. The power converting circuitry 240, comprised in the lighting body 200, is configurable to convert the primary power 15 to the secondary power 25. The primary power may be described by one or more primary parameters e.g. a primary voltage Vp, a primary periodicity fp and/or a primary current Ip. The skilled person understands that more parameters may be used, such as a phase difference between primary voltage Vp and the primary current Ip. The secondary power 25 may be described using corresponding one or more secondary parameters, e. g. a secondary voltage VS, a secondary periodicity fS and/or a secondary current IS. The secondary power 25 will typically be different from the primary power In one embodiment of the light fitting device 200, the secondary power 25 differs from the primary power 15 in that at least one of the secondary voltage VS, periodicity fS or current IS of the secondary power 25 is different from the respective primary voltage Vp, periodicity fp or current Ip. In a further embodiment, the primary power 15 accepts a primary voltage Vp of 230 V at a primary periodicity fp of 50 Hz and/or 110 V at a primary periodicity fp of 60 Hz. In one embodiment, the power converting circuitry 240 is configured to provide a secondary voltage VS of between 5 to 24 V at a secondary periodicity fS of 0 Hz, i.e. DC. In one embodiment, the power converting circuitry 240 is configured to provide a secondary voltage VS of betweento 48 V at a secondary periodicity fS of 50 Hz. In one embodiment, the power converting circuitry 240 is configured to, when loaded, provide a secondary current IS of between 100 mA to 5 A at a secondary periodicity fS of0 Hz, i.e. DC.

With reference to Fig. 4, some non-limiting embodiments of to the power converting circuitry 240 will be presented. It should be notet that these embodiments may be freely combined with one another and any other embodiment presented in this disclosure. In one embodiment of the power converting circuitry 240, the power converting circuitry 240 comprises a controller 243 for controlling the secondary power 25. This controlling may be achieved by controlling at least one of the secondary parameters presented earlier, the secondary voltage VS, periodicity fS and/or current IS of the secondary power With continued reference to Fig. 4. In some embodiments, the power converting circuitry 240 is configurable to provide, at the lighting body connector 220, the secondary power 25 at one of a number of different secondary powers 25. These different secondary powers 25 may be defined as different power configurations 2461,z,..,n. wherein each power configuration 2461,z,..,n may be configured such that, when it is used at the power converting circuitry 240, the power converting circuitry 240 provides the secondary power 25 with secondary parameters VS1,Sz,..,Sn, IS1,Sz,..,Sn, fS1,Sz,..,Sn configured by the used power configuration 2461,2,..,n. In other words, different secondary powers 25 may be provided depending on power configuration 2461,z,..,n. A particular power configuration 2461,z,..,n may be selected by means of one or more selectors 245. The one or more selectors 245 may be mechanical switches, e. g. dip- switches, potentiometers, jumpers etc., or configurable software switches or flags. The mechanical switches may be connected to electrical circuitry that directly or indirectly affects one or more of the secondary parameters differently depending on the setting of the switch. Altematively, or additionally, the mechanical switches may be used to switch voltages of e.g. a digital or analogue port of the controller 243. In some embodiments, a mechanical switch may very well be used to control a software switch. The skilled person understands, after reading this disclosure, that the way the one or more selectors 245 may be used to select different power configuration 246 are numerous and that not all are feasible to present herein.

In one or more embodiments, the power converting circuitry 240 may further be provided with a wireless communication module 247 for wireless communication of e.g. control data. The wireless technology or protocol used by the wireless communication module 247 may be any suitable technology and protocol such as infrared, IR, or radio frequency, RF, technology and protocols such as Bluetooth, cellular technology, LPWAN technology, Zigbee, KNX RF etc. in the case of RF technology.

In one exemplary embodiment, the power converting circuitry 240 may comprise a wireless communication module 247 configured to receive commands indicating a particular power configuration 246i,2,..,n. The power converting circuitry 240 may be configurable to provide, at the lighting body connector 220, the secondary power 25 at the indicated configuration 246i,2,..,n.

In one exemplary embodiment, the power converting circuitry 240 may comprise a wireless communication module 247 and one or more selectors 245. The selector, or the selectors 245, may be placed at a configuration such that the secondary power 25 is controlled using control commands and/or control data received via the wireless communication module 247. In a further embodiment, the wireless communication module 247 may be used to control the secondary power 25 such that e.g. dimming effects of the are achieved at the lighting body 20. It should be readily understood that the wireless communication module 247 may be replaced by a wired communication module. Further to this, additional functionality may very well be added to the power converting circuitry e.g. control of light temperature provide by the lighting body20, control of color of light provided by the lighting body 20 and the secondary power 25 may be expanded with e. g. control interfaces(s) in order to communicate control data to the lighting body In one embodiment, the lighting body connector 220 is configured to interface with the one or more selectors 245 so that a lighting body 20 can be configured to select a power configuration 246i,2,..,n based on how it interfaces with the lighting body connector 240. This may be achieved by having the lighting body connector 220 provided with e.g. grooves, bumps, pins, slots etc. that are arranged to depress/activate all, none or some of the selectors 245 operatively connected to the power converting ll circuitry 240 such that the power configuration 2461,2,..,n suitable for the lighting body 20 is selected. In other Words, the lighting body connector 220 may be described as having a particular keying interface that unlocks a particular mode of operation of the light fitting device so that the desired secondary power 25 is received.

In one alternative embodiment of the light f1tting device 200, it comprises a battery 249, see Fig. 4. The battery 249 is preferably operatively connected to the electronic power converting circuitry 240 such that the battery 249 may provide the secondary power 25 to the lighting body connector 220 when e. g. no primary power l5 is provided. In a further embodiment, the battery 249 is a rechargeable battery 249 that may be charged when the light fitting device 200 is connected to the primary power l5. The charging functionality may be e.g. comprised in the electronic power converting circuitry 240 or provided by a separate charging circuitry. Having this backup battery 249 makes it possible to provide lighting also in case of a power failure. It may be that the lighting, i.e. the secondary power, provided in case of a power failure, i.e. operation from the battery 249, is different from the lighting provided when the light f1tting device 200 is powered from the primary power l5. The light fitting device 200 may be configured to provide special emergency lighting when powered from the battery 249. This may be accomplished e.g. through automatic selection of a predeterrnined power configuration 2461,z,..,n of the one or more power configurations 2461,z,..,n when no primary power l5 is provided. The automatic selection may be based on a predeterrnined configuration or selected by said one or more selectors Tuming to Fig. 5a, a perspective view of a light fitting device 200 according to a non-limiting embodiment is shown together with three mutually perpendicular coordinate axis X, Y, Z for illustrating the orientation of the perspective view. In Fig. 5a, the power connector 2l0 is accessible through the housing 250. The power connector 2l0 is, in Fig. 5a, shown as an IEC CS connector but the skilled person understand, after reading this disclosure, that the power connector 2l0 may be realized using any suitable power connector 2l0 even those provided with protective grounding such as IEC Cl4 connectors. Depending on legislation and recommendations, the need for protective grounding of the light f1tting device 200 via the power connector 2l0 may be required. It may be that the form and material of the housing 250 will affect ifprotective grounding of the light f1tting device is required or not. In some legislation protective grounding is required, if the housing 250 comprises an electrically conductive material such as metal. In one embodiment of the light f1tting device 200, it comprises a housing forrned from a material that is an electrical insulator. As mentioned above, this is benef1cial since it will remove the requirement for protective grounding and thereby a smaller, cheaper and leaner power connector 210 may be used. Further to this, a cord connecting the light f1tting device 200 to mains power can be provided with two conductors instead of three as in the case of protective ground and consequently reducing the cost of extemal wiring.

The housing 250 introduced earlier, may be formed such that the extemal interfaces, the power connector 210 and the lighting body connector 220 are accessible from an outside the housing 250 as illustrated in Fig. 5a. However, in some embodiments, the power connector 210 is intemal to the housing 250 and accessible by opening the housing 250, the same may apply to the lighting body connector The ceiling attachment means 230 will now be explained in further detail. The ceiling attachment means 230 may be any suitable means for attaching the light f1tting device 200 to a functional ceiling 10. Preferably, the ceiling attachment means are formed such that the light f1tting device 200 can be easily, typically without the use of tools, mounted and removed from the rails 11 of the functional ceiling 10. The ceiling attachment means 230 may be formed as one or more clips or clamps adapted to clamp about the rails 11 of the functional ceiling 10. Preferably, the ceiling attachment means 230 are embodied by magnets 230. Using magnets for the ceiling attachment means 230 makes installation and refurbishing extremely simple and cost effective when the rails 11 of the functional ceiling are formed from a material with magnetic properties, i.e. a magnetic material. Typically, the rails 11 of the functional ceiling are formed from a magnetic material such as a ferromagnetic or ferrimagnetic material.

The light f1tting device 200 may be attached also to a rail 11 without a magnetic material. This may be accomplished by e.g. having plates or discs of materials with magnetic properties provided on an inside of the rail 11. These plates or discs allows the magnets 230 to magnetically connect to the plates or discs through the railand thereby attaching the light f1tting device 200 to the rail 11. In other words, themagnetic ceiling attachment means 230 is possible to use also when rails ll made from plastic or other non-magnetic materials are used.

In the embodiment of Fig. 5a, the magnets 230 are described as provided on an exterior of the housing 250 but the magnets 230 may be hidden from view. This means arranging the magnets 230 inside the housing 250 such that the magnetic force acts through the housing 250. The example with the hidden magnets 230 typically require the housing 250 to be made from a non-magnetic material but will in tum allow greater freedom of design when forrning the exterior of the housing. The number of magnets 230 may be chosen depending on the properties, e.g. magnetic force, of each magnet and the weight of the light f1tting device 200 in combination with the weight and torque provided by the lighting body 20. These magnets 230 may be oriented in a singular direction such that they may attach snuggly to a functional ceiling presenting a substantially flush surface for mounting, e. g. the rails 11 of a functional ceiling 10 comprising acoustically dampening plates.

Retuming again to Fig. 5a and Fig. 5b, a preferred embodiment of the ceiling attachment means 230 will be explained. The light fitting device 200 embodied in Figs. 5a-b is provided with one or more magnets 230 facing in an upward direction Y and in a sideways direction X. The upwards direction Y is preferably substantially perpendicular to the sideways direction X. Having magnets 230 arranged in this manner allows the light f1tting device 200 to interface and attach to the rail 11 of the functional ceiling 10 in two directions X,Y. This will allow for a more secure attachment to the rail 11 when compared to having magnets 230 or other attachment means 230 in only one direction. The substantially perpendicular arrangement of the magnets 230 allows them to attach to rails 11 of any height, length and/or width as long as they have at least one substantially planar surface for the magnets 230 to interface with. Preferably, which is typically the case, the rails ll are formed in an U-shape with perpendicular comers such that they interface with the light f1tting device 200 in two directions X,Y.

In the embodiment shown in Fig. 5a, the light f1tting device 200 is provided with two magnets 230 facing in the sideways direction X and one magnet 230 facing in the upward direction Y. This is just one embodiment and the invention should not be construed as limited to this particular configuration of magnets 230. However, theinventors of this disclosure have realized that this particular configuration of magnets 230 is especially benef1cial since it provides a stable and secure attachment of the light f1tting device 200 to the rail 11. This is in part due to the particular forrn of the light f1tting device 200 of Fig. 5a, wherein the light f1tting device 200 has center of mass distanced from the rail 11 in the sideways direction X. In an alternative embodiment wherein the light f1tting device 200 has a center of mass shifted in a downward direction, opposite to the upward direction Y, it may be more benef1cial to have more magnets 230 facing the upward direction Y than the number of magnets 230 facing the sideways direction X. The center of mass of the light f1tting device 200 typically pertains to the location of e.g. the electronic power converting circuitry 240 inside the housing 250 of the light fitting device 200. The skilled person will know, after digesting the teachings herein, how to design the fastening means 230 such that a stable and secure, but still removable, attachment is achieved of the light f1tting device 200 to the rail The light fitting device 200 depicted in Fig. 5a has further benefits. The arrangement of the ceiling attachment means 230 allows the light f1tting device 200 to be attached to, and removed from, a bottom side of the functional ceiling 10, i.e. from the Y-direction or a floor-side of the functional ceiling 10. This is benef1cial since mounting, movement and removal of the light f1tting device 200 is possible without having access to a top side of the functional ceiling 10. This allows the height of ladders, lifts and/or platforrns used for accessing the light f1tting device 200 to be reduced. The working environment of a person moving, attaching, adjusting or removing a light fitting device 200 is thereby made safer and more convenient. The feature of attaching and removing the light f1tting device 200 form the bottom side of the functional ceiling 10 may be accomplished by other arrangements of the ceiling attachment means 230 wherein i.e. all ceiling attachment means 230 are arranged in the same direction of the light f1tting device 200. The feature of attaching and removing the light fitting device 200 form the bottom side of the functional ceiling 10 is especially benef1cial when the ceiling attachment means 230 comprises magnets 230 since this further enables simple, safe, convenient and tool-less attachment and/or removal of the light fitting device.

In Fig. 5b, a bottom view of the light fitting device 200 according to one embodiment is shown. The bottom view is shown with the corresponding reference for orientating of the bottom view as in Fig. 5a. From this view of this exemplary embodiment of the light fitting device 200, the housing 250 is shown to comprise a lighting body connector lid 255 and a lighting body connector opening 253. The lighting body connector lid 255 may be a removable or movable part of the housing 250 made from the same or a different material as the housing 250. The lighting body connector lid 255 is preferably large enough such that it, when opened or removed from the housing 250, allows for the attachment of the lighting body 20 to the lighting body connector 220. The lighting body connector lid 255 may, in some embodiments of the light fitting device, expose the selectors 245 shown in Fig. 4 such that a desired power configuration 2461,z,..,n may be selected when the lighting body 20 is attached to the light fitting device 200. The lighting body connector lid 255 may be attached to the housing 250 in any suitable manner, such as e. g. one or more hinging arrangements, one or more screws, one or more clips and/or by a design that is lockable when mating the lighting body connector lid 255 with the housing With continued reference to Fig. 5b, the lighting body connector opening 253 is provided through the housing 250 such that the lighting body 20 may extend out from the housing 250 when attached to the light f1tting device. The lighting body connector opening 253 is in Fig. 5b, formed in the housing 250 and the lighting body connector lid 255. However, the lighting body connector opening 253 may altematively be formed solely in the lighting body connector lid In Fig. 6a, a perspective view of the lighting body 20 and part of the lighting body connector 220 according to a non-limiting embodiment is shown. As mentioned earlier, the lighting body connector 220 is a connector 220 formed to provide both an electrical interface together with a mechanical interface from the light f1tting device 200 to the lighting body 20. The lighting body connector 220 is illustrated as a disc with a radial cutout 225 in Fig. 6a. The radial cut out 225 is adapted to receive a mating lighting body connector 27 of the lighting body 20. The mating lighting body connector 27 comprises an interface disc 23 and an interface shaft 2l wherein the interface shaft is connected, at one end, to a head 29 of the lighting body 20 and, at the other end, to theinterface disc 23. The interface shaft 21 may extend through the interface disc 23 or terrninate at or in the interface disc 23. The interface shaft 21 may be provided with an inner lumen 22 extending, at least partly, through the interface shaft 21 and terrninating for instance at the ends of the interface shaft 21 or at radial holes in the interface shaft 21. The inner lumen 22 may be adapted to provide an electrical connection to the head 29 of the lighting body 20. The interface disc 23 is adapted to interface with the lighting body connector 220 when the interface shaft 21 of the lighting body 20 has been inserted into the radial cut out 225. This means that a width of the radial cut out 225 is wider than a diameter of the interface shaft 21 but more narrow than a diameter of the interface disc 23. This arrangement allows the lighting body 20 to be removable attached to the light fitting device 200 and still be possible to rotate about a center axis of the interface shaft 21. The interface disc 23 and/or the lighting body connector 220 may be provided with rotation hindering means such that the head 29 can rotate only one revolution about the center axis of the interface shaft 21. A weight of the head 29 and the interface shaft 21 will allow the interface plate to rest on top of the lighting body connector 220 by gravitational force.

In one embodiment, the light f1tting device 200 may be provided with a guide plate arranged such that the interface disc 23 is sandwiched between the guide plate and the lighting body connector when the lighting body 20 is attached to the light f1tting device 200. This may be beneficial in order to ensure that the lighting body connector 220 and the interface disc 23 are horizontally aligned, or at least substantially aligned, also when the head 29 exerts a torque on the interface shaft 21. In order to reduce the risk of the interface shaft 21 sliding out of the radial cut out 225, the connector lid 255 may be formed to avoid such movement, by e. g, defining one movement of the interface shaft 21 by the lighting body connector opening 253. Note that Any other suitable locking mechanism may be utilized. The interface disc 23 and the interface shaft 21 may be one single component. The radial cut out 225 is clearly visible in the solitary top view of the square, or rectangular, lighting body connector 220 of Fig. 6b.

In Fig. 6c, the same top view as in Fig. 6b is presented, but with the mating lighting body connector 27 arranged in the radial cut outAs mentioned above, the interface plate 23 may be arranged such that it interfaces not only the lighting body connector 220, but also the one or more selectors 2461,z,..,n of the electronic power converting circuitry In Fig. 7, a perspective view of the light f1tting device 200 with a lighting body 20 attached is shown. The corresponding coordinate axis as presented in Figs. 5a-b are shown in Fig. 7. The interface shaft 2l of the lighting body 20 extends into the housing 250 of the light f1tting device 200 via the lighting body opening 253. The mating between the light f1tting device 200 and the lighting body is hidden by the lighting body connector lid.

An electrical connection is required between the electronic power converting circuitry 240 and the lighting body 20. This may be realized in many different ways, and the following examples are suggested embodiments but the invention is not limited to these examples. One implementation may be to directly wire the head 29 of the lighting body 20 to the electronic power converting circuitry 240. This may be accomplished by routing wires, providing the secondary power 25, via the inner lumen 22 of the interface shaft 2l and connecting them to the electronic power converting circuitry 240. The electronic power converting circuitry 240 may be provided with multiple outputs arranged or configurable to provide different secondary powers 25. The connection to the electronic power converting circuitry 240 may be such that the secondary parameters of the secondary power 25 are selected based on the output of the electronic power converting circuitry 240 that is operatively connected to the head 29. For instance, one output of the electronic power converting circuitry 24 may provide 5 V DC and another 24 V AC.

The wires may be routed such that they may be twisted many times before breaking to allow the head 29 to rotate about the center axis of the interface shaft 2l. In one embodiment, the interface disc 23 and/or the lighting body connector 220 are provided with the rotation hindering means mentioned above which will remove the risk of the wires breaking due to tensioning of the wires from rotation of the head Altematively, the electrical connection may be provided as a sliding bearing between the interface disc 23 and the lighting body connector 220. This may be realized by having one or more electrical conductors on the side of the interface disc 23 facingthe lighting body connector 220 and corresponding one or more electrical conductors on the side of the lighting body connector 220 facing the interface disc 23. The sliding bearing with an electrical connection may be designed with any number of conductors. As exemplified above, different conductors may be connected to different outputs of the electronic power converting circuitry 240 thereby providing different secondary parameters of the secondary power 25 to the lighting body 20. In such an embodiment, the interface disc 23 may be adapted to connect to specific conductors on the lighting body connector depending on power requirements of the lighting body It should be mentioned that the different outputs of electronics power converting circuitry 240 may be used in conjunction with the one or more selectors 245. This enables the reduction of the risk that the incorrect secondary power 25 is provided to the lighting body 20. The electronics power converting circuitry 240 may, e.g. for cost reasons, not be designed to provide all power conf1gurations 2461,z,..,n at the same time to multiple outputs, and this means that both the correct output needs to be selected and the correct selector 245 needs to be selected in order for the lighting body 20 to work properly.

Claims (14)

1. A light fitting device (200), for removable attachment of a lighting body (20) to a rail (11) of a functional ceiling (10), the light f1tting device (200) comprising a power connector (210) for receiving a primary power (15), a lighting body connector (220) for receiving the lighting body (20), a ceiling attachment means (230) and an electronic power converting circuitry (240); wherein the primary power (15) is an altemating current, AC, power, the primary power connector (210) is operatively connected to the lighting body connector (220) by means of the electronic power converting circuitry (240), and the electronic power converting circuitry (240) is configurable to convert the primary power (15) to a secondary power (25), wherein the secondary power (25) is a direct current, DC, power, and provide the secondary power (25) to the lighting body connector (220), wherein the ceiling attachment means (230) comprises at least one magnet (230) for removable attachment of the light f1tting device (200) onto the rail (11) of the functional ceiling (10) having ferromagnetic properties.

2. The light f1tting device (200) of claim 1, wherein the ceiling attachment means (230) comprises a plurality of magnets (230) facing in both a sideways direction (X) and in an upward direction (Y) for removable attachment of the light f1tting device (200) onto a~§j'_1_ç;__functional ceiling (10) having ferromagnetic properties.

3. The light f1tting device (200) of any of the preceding claims, wherein the ceiling attachment means (230) is arranged such that the light f1tting device (200) can be removably attached to the functional ceiling (10) in the upward direction (Y) towards the functional ceiling (10).

4. The light f1tting device (200) of any of the preceding claims, wherein the secondary power (25) is different from the primary power (15) in that at least one of a secondary Voltage (VS), periodicity (fS) or current (IS) of said secondary power (25) differs from a respective primary voltage (Vp), periodicity (fp) or current (Ip).

5. The light f1tting device (200) of any of the preceding claims, wherein the electronic power converting circuitry (240) comprises a controller (243) configured to control at least one of the secondary voltage (VS), periodicity (fS) or current (IS).

6. The light f1tting device (200) of any of the preceding claims, wherein the electronic power converting circuitry (240) is configurable to provide the secondary power (25) at one of a plurality of different power configurations (2461,2,..,n).

7. The light fitting device (200) of claim 6, wherein at least two power configurations (2461,z,..,n) of the plurality of different power configurations (2461,z,..,n) differ in the voltage (VS), periodicity (fS) and/or current (IS).

8. The light f1tting device (200) of claim 6 or 7, further comprising one or more selectors (245) operatively connected to the electronic power converting circuitry (240) for selecting one of the plurality of different power configurations (2461,2,..,n).

9. The light f1tting device (200) of any of the preceding claims, wherein the electronic power converting circuitry (240) comprises a wireless communication module (247) for wirelessly receiving control data, wherein the control data comprise control commands for controlling at least one of the secondary voltage (VS), periodicity (fS) or current (IS).

10. l0. The light f1tting device (200) of any of the preceding claims, wherein the light f1tting device (200) comprises a housing (250) of a material that is an electrical insulator.

11. ll. The light fitting device (200) of claim l0, wherein the power connector (2 l 0) is a connector (2 l 0) without protective grounding.

12. The light fitting device (200) of any of the preceding c1ain1s, Wherein the lighting body connector (220) is arranged to provide n1echanica1 support for a lighting body (20) connected to the lighting body connector (220).

13. The light fitting device (200) of c1ain1 12, Wherein the lighting body connector (220) is forrned With a radia1 cut out (225) adapted to receive a niating lighting body connector (27) of the lighting body (20) such that the lighting body (20) can be rotated about a center axis of an interface shaft (21) of the lighting body (20).

14. The light fitting device (200) of any of the preceding c1ain1s, Wherein the primary power (15) is provided from a n1ains power (12).