EP2577153B1

EP2577153B1 - Light fitting for led strips

Info

Publication number: EP2577153B1
Application number: EP11727658.4A
Authority: EP
Inventors: Stephan Gunst; Frank Sinnaeve
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-05-30
Filing date: 2011-05-28
Publication date: 2018-02-28
Anticipated expiration: 2031-05-28
Also published as: WO2011151272A1; EP2577153A1

Description

FIELD OF THE INVENTION

The invention relates to the field of lighting. More particularly, the present invention relates to systems for fitting a plurality of light emitting diodes such as for example light emitting diode strips.

BACKGROUND OF THE INVENTION

Initially, light emitting diodes (LEDs) were mainly used as indicators or signs for identifying the status of a system or as components in LED displays, such as for example in stadium displays or as dynamic message displays. Meanwhile, the LED market has substantially grown. LEDs are now for example also used for traffic lights and signals, exit signs, emergency vehicle lighting, Christmas lights, high-mounted brake lights, glowsticks, etc.
Over the years, a plurality of types of LEDs and LED fittings have been developed, each having particular properties. Single colour as well as white emitting LEDs exist. LEDs with higher efficiency and power have been developed. LEDs with different type of mountings have been introduced, such as surface mounted or mounted using through holes on a printed circuit board.
A class of applications that still is strongly developing is the use of LEDs in lighting and illumination applications, which has amongst others been made possible due to the development of high efficiency and high power white emitting LEDs having a long lifetime and low power consumption. Different types of white emitting LEDs have been developed. One type of white emitting LED is referred to as multi-color LED, whereby a plurality of light emitting diodes emitting at different wavelenghts or in different wavelength regions is combined thus resulting in an overall white emission. A second type of white emitting LED is referred to as a phosphor converted LED, wherein a LED emission at short wavelengths is created which is converted by a fluorescent layer into white emission. As indicated above, light emitting diodes (LED) have a significant longer life time than the incandescent light bulbs they typically are replacing in lighting applications. Nevertheless, the life time of LEDs still is significantly influenced by the cooling provided, especially in case of high power LEDs. Thermal management in this type of LEDs therefore has been extensively studied, resulting in a plurality of solutions, one thereof being the provision of a heat sink. LEDs for lighting and illumination applications have been made available in the form of light bulbs, LED lamps, LED strips, etc. Different types of LED strips exist. One example of a LED strip is a set of LEDs encapsulated in a flexible strip of translucent material. This typically results in a bulky packaging. Another example of LED strip is described in US2010/0097791 A1 , wherein a thin-profiled LED strip is provided having a set of LEDs positioned on a flexible printed circuit, covered with a thin flexible light- transmitting layer and having an electrical connector at one end.
Whereas LED light bulbs or LED lamps often make use of a similar electrical fitting and mechanical positioning system as for other lamp types, this is less the case for LED strips. One example of electrical fittings used in LED strips are electrical connectors at the end of the LED strip.
US 2009/0239393 describes a LED system with a conductive magnetic coupling system for coupling a set of LEDs to a LED fitting. The conductive magnetic coupling system provides both a bonding mechanism for securing the components to one another as well as a mechanism for providing electrical and data signal connectivity. LED strips are especially suitable for use in small spaces as they can be compact in size, but the small available space for mounting and/or connecting, may result in difficulties for mounting and/or connecting the LED strip in the fitting. In some applications, LEDs are used in indirect illumination systems. Such illumination systems typically comprise a holder for mounting the LEDs and a blocking element for blocking direct view of the LEDs, thus creating the experience of indirect illumination.
US2007/263379A1 discloses a LED strip fitting which is considered the closest state of the art for the LED strip fitting of claim 5. WO2008/099306A1 discloses a LED strip which is considered the closest state of the art for the LED strip of claim 1.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide systems for illuminating using LED strips. It is an advantage of the present invention that an easy and user-friendly electrically and/or mechanically positioning and/or connection can be obtained.
It is an advantage of the present invention that LED strips are provided that can be easily applied for indirect lighting. It is an advantage of the present invention that LED strip fittings or luminaires can be provided for indirect lighting, wherein the individual LED sources are not directly visible, without the need for a diffusing filter, such as for example a glass filter.
It is an advantage of the present invention that LED strip fittings are provided, allowing easy mounting of LED strips in the LED strip fitting e.g. in case of installation or in case of replacement after failure of one or more of the LED elements or strips.
It is an advantage that easy mounting is obtained even at positions where the mounting space for the LED strip is not directly in a line of sight of the user or where the available space for manipulating the LED strip is small.
It is an advantage of the present invention that LED strip fittings and corresponding LED strips are provided that allow accurate positioning of the LED strip, e.g. without the risk of the LED strip displacing in the fitting upon use.
It is an advantage of at least some embodiments that LED strip fittings can be provided wherein thermal control, e.g. by heat dissipation or cooling, of the fitting can be easily obtained.
It is an advantage of at least some embodiments that LED strip fittings can be provided that can easily be integrated in profiles for finishing a room, allowing to amplify the effects of contemporary minimalistic architectural designs by isolating or connecting lines, planes and volumes in a place, using fine light lines.
It is an advantage of at least some embodiments that a seamlessly fit in walls, ceilings, floors or furniture can be obtained. It is an advantage of some embodiments that a pure and homogeneous light output can be obtained.
It is an advantage of at least some embodiments that easy selection of the length of the LED strip fitting can be made, as well as that easy connection between different LED strip fittings can be made.
It is an advantage of at least some embodiments that compact LED strip fittings with a limited number of electrical contacts can be provided, while still allowing accurate and relatively complex driving of the LED strip and/or its light emitting elements. It is an advantage of at least some embodiments that a reliable and physically small driver for driving the LED strip and/or its light emitting elements can be obtained.
The above objectives are accomplished by devices according to the present invention laid down in the appended independent claims and its preferred embodiments laid down in the dependent claims.
The present invention relates to a LED strip fitting for holding at least one LED strip as defined in any of claims 1 to 4, the LED strip fitting comprising a cavity adapted for receiving the at least one LED strip so that after installation of the LED strip in the LED strip fitting, the LED strip is substantially not directly visible by a viewer and indirect lighting is provided. It also comprises at least one set of contact electrodes for inducing pressure based contact with the electrical contact electrodes of the at least one LED strip, a magnetically interacting element for magnetically interacting with the at least one LED strip for positioning the at least one LED strip, the magnetically interacting element being adapted for providing, by magnetic interaction with the at least one LED strip, a pressure between the at least one set of contact electrodes and the contact electrodes of the at least one LED strip so as to obtain electrical contact between the LED strip fitting and the at least one LED strip. The LED strip fitting further comprises in a cross-section perpendicular to the longitudinal direction of the LED strip fitting a complementary curved portion wherein the curved portion disposed on the one side of the positioning means of the LED strip is adapted for being fitted and a complementary cornered portion wherein the cornered portion disposed on the one side of the positioning means of the LED strip is adapted for being fitted.
The LED strip fitting further may comprise at least one profile portion for receiving construction material on the profile portion, the LED strip fitting thus forming a construction profile for finishing any of a wall, a ceiling or construction such as furniture, the cavity being formed in the construction profile such that it is suitable for indirect lighting of the wall, the ceiling or the construction.
The magnetically interacting element may extend along a longitudinal direction of the LED strip fitting.
The fitting may comprise a heat sink for removing heat from the LED strip.
The heat sink of the LED strip fitting may comprise cooling fins for cooling the LED strip fitting.
The LED strip fitting may be adapted for contacting the at least one set of electrical contacts from a second side or a side different from the side for contacting electrodes of the LED strip such as for example a side opposite the side for contacting electrodes of the LED strip, thus providing the possibility to contact the at least one set of electrical contacts with an interconnection means for interconnecting different LED strip fittings.
The present invention furthermore relates to a kit of parts comprising a LED strip according to any of claims 1 to 4 and a LED strip fitting according to any of claims 5 to 12.
The present invention relates to a LED strip comprising at least one light emitting device, the LED strip further comprising at least one set of pressure based electrical contact electrodes for electrical connection with a set of contact electrodes of a LED strip fitting, and a positioning means comprising on one side a magnetically interacting element for positioning the LED strip by magnetic interaction with the LED strip fitting, the magnetically interacting element being adapted for providing, by magnetic interaction with the LED strip fitting, a pressure between the at least one set of pressure based electrical contact electrodes and the contact electrodes of the LED strip fitting so as to obtain electrical contact between the LED strip and the LED strip fitting, wherein the LED strip comprises a driving module for generating drive signals for driving the LED strip, wherein the positioning means comprises in a cross-section perpendicular to the longitudinal direction of the LED strip on one side a curved portion, adapted for fitting in a complementary curved portion in the LED strip fitting, and a cornered portion adapted for fitting in a complementary shaped portion in the LED strip fitting, said curved portion) and said cornered portion extending in said longitudinal direction.
The driving module may be adapted for receiving control data from a controller and for generating drive signals for driving the LED strip based on the received control data. The driving module may be adapted for receiving control data from the controller via an intermediate driving module from another LED strip.
The magnetically interacting element may extend along a longitudinal direction of the LED strip. It is an advantage of embodiments according to the present invention that accurate positioning can be obtained as positioning and/or fixation is obtained at different positions along the longitudinal direction of the LED strip.
The LED strip may comprise different sets of pressure based contact electrodes along a longitudinal direction of the LED strip. It is an advantage of embodiments according to the present invention that the plurality of pressure based electrical contact electrodes can provide electrical contact between different parts of a LED strip fitting that are not in direct electrical contact with each other.
Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A, FIG. 1B, FIG. 1C and FIG. 1D illustrate a cross-sectional view, a top view, an elevated front view and an elevated back view respectively of an example of a LED strip comprising a fixation means for positioning the LED strip and for assisting in electrically contacting the LED strip in a LED strip fitting, according to an embodiment of the present invention.
FIG. 2 illustrates a cross-sectional view of an example of a LED strip fitting comprising a LED strip as shown in FIG. 1A, according to an embodiment of the present invention. FIG. 3A to FIG. 3C illustrates an alternative example of LED strip fitting for a LED strip providing direct illumination not supporting the present invention. FIG. 4A to FIG. 4E illustrate an example of a construction profile being a LED strip fitting for providing indirect illumination in a wall, FIG. 4A to FIG. 4C illustrating a cross-sectional view and elevated top views of LED strip fittings with a LED strip incorporated, FIG. 4D illustrating a construction profile without LED strip, FIG. 4E illustrating an embedded construction profile according to an embodiment of the present invention.
FIG. 5A to FIG. 5C illustrates an example of another construction profile comprising a LED strip fitting for providing indirect illumination in a corner between two walls or between a wall and a ceiling, FIG. 5A illustrating a construction profile with LED strip incorporated, FIG. 5B illustrating a construction profile without LED strip, FIG. 5C illustrating an embedded construction profile according to an embodiment of the present invention.
FIG. 6A to FIG. 6C illustrate an example of an illumination spot comprising two portions, a portion for guiding the radiation indirectly to the viewer as shown in FIG. 6B and a portion for mounting the LED strip in FIG. 6C, the illumination spot being adapted for comprising a LED strip for providing indirect illumination according to an embodiment not supporting the present invention.
FIG. 7 illustrates another LED strip fitting according to an embodiment not supporting the present invention.
FIG. 8 illustrates an interconnection means for connecting different LED strip fittings.

Any reference signs in the claims shall not be construed as limiting the scope.
In the different drawings, the same reference signs refer to the same or analogous elements.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The invention will now be described by a detailed description of several embodiments of the invention. It is clear that other embodiments of the invention can be configured according to the knowledge of persons skilled in the art, the invention being limited only by the terms of the appended claims.
Where in embodiments of the present invention reference is made to a light emitting device strip fitting or LED strip fitting, reference is made to a lamp holder, wherein a LED strip can be positioned and which allows or provides for electrical connection of the LED strip to a power source, such as a battery or a mains voltage. Where reference is made to fitting or LED strip fitting, also the terminology lamp holder or luminaire is encompassed.
In a first aspect, the present invention relates to a LED strip for providing lighting or illumination. The LED strips are especially suitable for use in indirect lighting, although embodiments of the present invention are not limited thereto, and the LED strips can also be used for other applications, such as for example direct lighting or illumination. According to embodiments of the present invention, the LED strip is a lighting or illumination source comprising at least one light emitting device, in some embodiments being a plurality of light emitting devices. If a plurality of light emitting devices are used, these may be arranged in a line matrix, column matrix or m x n matrix, although embodiments of the invention are not limited thereto. Also non arranged LEDs may be used. The at least one light emitting device may be any type of light emitting device such as for example more conventional LEDs, high power LEDs, coloured LEDs, white LEDs, single coloured non-dimmable LEDs, single colour dimmable LEDs, tunable white LEDs, RGB LEDs, ...The LED strip according to the present invention comprises at least one set of pressure based electrical contact electrodes for electrical connection with a set of electrode contacts of a LED strip fitting by contacting the contact electrodes using pressure. The electrical contact electrodes for pressure based contact may for example be contacts that can be pressed to corresponding electrode contacts by a resilient means, such as for example a spring. The LED strip furthermore comprises a positioning means comprising a magnetically interacting element for positioning the LED strip by magnetic interaction within the LED strip fitting. The magnetically interacting element thereby is adapted for providing, through magnetic interaction with the LED strip fitting, a pressure between the at least one set of electrical contact electrodes of the LED strip and the contact electrodes of the LED strip fitting so as to obtain electrical contact between the LED strip and the LED strip fitting.
The electrical contact electrodes may be made of any conductive material, such as for example - but not limited to - copper. The electrical contact electrodes may be provided as at least one set of electrodes, such a set of electrodes comprising at least two electrical contact electrodes. Advantageously, more than one set of electrodes may be provided. The provision of more set of electrodes may on the one hand provide a type of redundancy, such that if contact for one set of contacts fails making accurate contact, good contact still can be reached through one of the other sets. Furthermore, each resilient electrical contact itself also may be shaped such that it has more than one position for contacting a counter electrode. The resilient electrical contact may for example be w-shaped. Another advantage can be obtained for configurations wherein more than one LED strip fitting is used and whereby the LED strip is positioned partly on one fitting and partly on another fitting. Providing different sets of contacts for the LED strip may allow overcoming an interruption of electrical contacts at the side of the fittings, thus allowing to still obtain an electrical operating circuit. The different sets of contacts may be provided at different positions along the length direction of the LED strip. According to one embodiment, each set of electrodes may comprise more than two electrodes, thus allowing to drive for example different LEDs provided in the LED strip. If for example different coloured LEDs are used, the electrical circuit in the LED strip may be adapted so that different coloured LEDs can be selected by selecting different electrodes within the set for the driving. In such a way, the LED strip may be tuned to a particular overall colour or to a mixture of different colours.
According to the present invention, the LED strip comprises a driving module for generating drive signals for driving the LED strip. Such drive signals may be derived or generated based on control data provided by a controller being part of the lighting system. The driving module thus may be adapted for receiving control data from a controller and for generating drive signals for driving the LED strip based on the received control data.
It is an advantage that the driving module may be incorporated in the LED strip, as this allows reducing the number of electrical contacts that are required. With a driving module incorporated in the LED strip, the number of electrical contacts for contacting the LED strip may be limited to the number of contacts required for powering the device, while drive signals for the light emitting devices on the LED strip can be obtained separately, e.g. wireless, or through demodulating a modulated power signal.
This furthermore allows to prolong the LED strip fitting used to the length as required, e.g. using multiple fittings coupled to each other, as it reduces the requirements for drive signal transport along the LED strip fitting. The latter may in some embodiments be assisted by the fact that the driving module may be adapted for receiving control data from a controller via an intermediate drive module from another LED strip. In other words, the driving module may be adapted for receiving control data through another LED strip, e.g. an intermediate LED strip and/or a neighbouring LED strip. The driving module therefore may be adapted not only for receiving control data, but also for transmitting control data to other LED strips, e.g. neighbouring LED strips. Control signals may for example comprise signals for dimming or signals for inducing a colour change, although embodiments are not limited thereby.
In some advantageous embodiments, the driving module is adapted for receiving the control data in a wireless manner, i.e. through wireless communication. It is an advantage of embodiments of the present invention using driving modules adapted for wireless communication that such driving modules can be small or compact, such that integration in the LED strip can easily be made. The driving module may for example be a Bluetooth, wireless LAN or ZigBee based or compatible.
If for example ZigBee is considered, transmission or receipt of data control signals can be obtained making use of a low-data-rate short-range wireless network. For the example of ZigBee, different frequency bands can be used, optionally depending on the geographic region wherein the LED strip fitting is used, for example 868MHz, 915MHz or 2.4GHz. Furthermore ZigBee provides a sufficient data rate, e.g. up to 250 Kbits per second. Another advantage is that ZigBee devices can operate at low power. With respect to size, the ZigBee modules typically are compact so these can in at least some embodiments of the present invention be fitted into the LED modules. ZigBee modules also do not seem to suffer from signal disturbance due to the LED strip fitting, even if the profile is made of metal such as Aluminum. The driving module may be an electronic circuit for converting a modulation of an incoming electronic signal to driving signals for driving the at least one light emitting device. In some embodiments, the driving module may comprise an intelligent module for interpreting, e.g. demodulating, a modulated electrical or digital signal provided to the electrical contact, whereby modulation of the electrical signal in a particular way may correspond with a particular driving of the one or more LEDs. Such an intelligent module thus may convert a particularly modulated electrical or digital signal to different drive signals for the different LEDs, thus allowing driving the individual LEDs differently, resulting in e.g. a different overall colour emitted by the LED strip.
The magnetically interacting element may be a magnetic material or a metal material which can magnetically interact with a magnet in the LED strip fitting. The magnetically interacting element may for example be magnetite, cobalt, nickel, ferrite, ainico magnets, ticonal magnets, etc. Advantageously the magnetic material is permanent magnetic material such as for example hard magnetic materials, also referred to as permanent magnetic materials. Some examples thereof, the present invention not being limited thereby, can be commercial materials such as Arnokrom or Crovac. The magnetically interacting element may be in any suitable form, such as for example in the form of a plate or a film. The magnetically interacting element may have an elongated form and may extend along the length direction of the LED strip. In some embodiments, the magnetically interacting element may extend over at least 50%, advantageously over at least 75% of the length of the LED strip.
According to the present invention, the positioning means is provided with curved and corner-shaped portions adapted for assisting, by virtue of their shape, in positioning of the LED strip in the LED strip fitting. The curved and corner-shaped portions are such that they interact with a complementary shaped portion of the LED strip fitting. In this way, when the positioning of the LED strip and the LED strip fitting is accurate, the LED strip can for example be fully adjacent at certain sides with the LED strip fitting. Furthermore, during positioning, the combination of the magnetic force and the shape results in additional mechanical forces on the LED strip, so that an even more accurate positioning is obtained.
According to the present invention, the LED strip shape and the shape of the LED strip are such that that due to the magnetic interaction there is a good contact between the LED strip and the LED strip fitting, allowing to transfer heat from the LED strip to the LED strip fitting. The materials of the LED strip also may be selected for having a good thermal conductivity, such that heat is easily transferred. By way of illustration, embodiments of the present invention not being limited thereby, an exemplary LED strip according to an embodiment of the present invention is shown in FIG. 1A in cross-sectional view and in FIG. 1B in top view. Furthermore FIG. 1C and FIG. 1D show an elevated front view and an elevated back view of the LED strip 100. The LED strip 100 illustrates the electrical contact electrodes 120 for pressure based electrical contact, in the LED strip shown being 4 sets of electrical contact electrodes 120 for pressure based electrical contact. Furthermore, the magnetically interacting element 132 is shown being part of a positioning means 130. In the present example, the magnetically interacting element 132 extends along the full length of the LED strip. In the current example, the magnetically interacting element has a width of about 5mm and a thickness of about 2mm, although embodiments of the present invention are not limited thereby. The positioning means 130 of the present example furthermore has on one side a curved portion 134, adapted for fitting in a complementary curved portion in the LED strip fitting, and a cornered portion 136 adapted for fitting in a complementary shaped portion in the LED strip fitting. In FIG. 1B it is shown that the different LEDs that typically may be grouped on an intermediate device 150 may be mounted in the LED strip using any suitable means, such as by means of screws 152. It is an advantage of embodiments of the present invention that applying such screws 152 can be performed before the fitting of the LED strip into the LED strip fitting, thus avoiding mounting problems in small or difficult reachable spaces. The intermediate device may be a printed circuit board. In some embodiments the major part of the remaining body, e.g. besides the magnetically interacting element and the electrical contacts, can be made of any type of material such as for example a plastic or a metal, such as e.g. aluminum. For heat control reasons the material may be selected for having a high thermal conductivity.
Whereas in the present example the magnetically interacting material and the electrical contacts have been shown as lying in different planes of the LED strip, the latter is not required and magnetically interacting material and electrical contact can also be positioned in the same plane. An example not supporting the independent claims will be visible in FIG. 3A to FIG. 3C, as discussed later.
It is an advantage of the present invention that the positioning means with magnetically interacting element can provide both a good positioning and a good fixing of the LED strip in a LED strip fitting. This may for example allow that the LED strip may be mounted in any direction, without having the risk that the LED strip drops out of the LED strip fitting.
In a second aspect according to embodiments of the present invention, a LED strip fitting is provided. The LED strip fitting according to the present invention is suitable for operation with the LED strip as described in the first aspect. According to the present invention, the LED strip fitting comprises a set of contact electrodes for pressure based contacting electrical contact electrodes of a LED strip and a magnetically interacting element for magnetically interacting with a LED strip for positioning the LED strip. The magnetically interacting element is adapted for providing, by magnetic interaction with the LED strip a pressure between the at least one set of contact electrodes and the contact electrodes of the LED strip so as to obtain electrical contact between the LED strip fitting and the LED strip.
The set of electrodes of the LED strip fitting may comprise at least two electrodes, although also more electrodes may be provided. More than two electrodes may for example allow driving only a selected number of electrodes, resulting in the possibility to select colour if different colour LEDs are used, to drive only a certain part of the LEDs on the LED strip such that only a selected part of the LED strip is illuminating, etc. In this way colour selection of the LED strip can be performed. The LED strip fitting is adapted for operating with LED strips comprising a driving module for converting control signals into drive signals. In such an embodiment the number of electrodes can still be low, e.g. two, while control of the illumination, e.g. with respect to dimming or colour change, can still be obtained, for example by wirelessly obtaining control signals or by modulation/demodulation of control signals applied to the power signals. The LED strip fitting may comprise a controller for generating such control signals and/or modulation. The electrodes may be made of any electrically conductive material, such as for example copper. When a plurality of different LED strip fittings are used to form a long LED strip fitting, the electrodes may be electrically interconnected using interconnection pieces, although in some embodiments interconnection can also be provided via the LED strips, when these are positioned into place. The electrodes may advantageously extend along the full longitudinal direction of the LED strip fitting. The latter results in that the exact position along the longitudinal direction of the LED strip fitting is less critical. In some embodiments, the electrodes advantageously are arranged such that parallel connection of different LED strips in one or more LED strip fitting is obtained.
The magnetically interacting element in the LED strip fitting may for example be a magnetic element , in which case the LED strip itself may comprise merely a metallic material as magnetic interacting element, or for example the LED strip fitting may comprise merely a metallic material as magnetic interacting element, in which case the LED strip itself should comprise a magnetic element. The material may be applied in any suitable form, such as for example as a plate or film of material. In some embodiments the magnetically interacting element may extend along the length direction of the LED strip fitting. It may extend over the full length of the LED strip fitting, although embodiments are not limited thereto. In some embodiments, the magnetically interacting element may extend over at least 50%, advantageously over at least 75% of the length of the LED strip. According to the present invention, the LED strip fitting comprises curved and cornered shaped portions adapted for assisting in positioning of the LED strip. Such assisting may be by virtue of the shape of the curved and cornered portions. The shape of the curved and cornered portions is such that it is complementary to the shape of curved and cornered portions of the LED strip to be positioned. In this way, when the positioning of the LED strip in the LED strip fitting is accurate, the LED strip fitting can, at certain surfaces of the fitting, be adjacent to LED strip. Furthermore, during positioning, the combination of the magnetic force and the shape results in additional mechanical forces between the LED strip and the LED strip fitting, so that an even more accurate positioning is obtained.
It is an advantage of the present invention that a good direct contact between the LED strip fitting and the LED strip is obtained over e.g. one side of the LED strip, so that heat dissipation to the LED strip profile and optionally to a heat sink thermally coupled therewith can be obtained.
The LED strip fitting furthermore may comprise electrical components for providing power to the LED strip, driving the LED strip or providing control signals to the LED strip. Such components could be introduced in the LED strip fitting at any suitable position, for example positioned at a position opposite to where the LED strip is to be positioned with respect to the magnetic interacting element. In some embodiments intelligent driving can be performed, e.g. by modulating the electrical or digital driving signals, whereby interpretation of the modulated signal may indicate a certain driving pattern, such as a timing for the ON time of the individual light emitting devices, dimming or colour control, to be applied in the LED strip to the different LEDs. In such cases, the LED strip typically may comprise an intelligent driving module for translating the modulated driving signals in particular driving signals in the LED strip. As indicated above, when a LED strip with driving module implemented therein is used, the LED strip fitting may comprise a controller for providing control signals to the driving module. Such a controller may be adapted for providing control data to the LED strip for generating drive signals for driving the LED strip. The controller may transmit control signals for a number of LED strips to one or more driving modules which at their turn may transmit control signals to further driving modules of other LED strips or the controller may provide control signals to each of the LED strips separately. Control signals may for example comprise signals for dimming or signals for inducing a colour change, although embodiments are not limited thereby.
The controller may provide data to the driving modules through wireless communication. The controller may for example be a Bluetooth, wireless LAN or ZigBee based or compatible.
According the present invention, the LED strip fitting comprises a cavity adapted for receiving one or more LED strips so that, after installation of the LED strip, the LED strip is substantially not or not directly visible by a viewer and that indirect lighting is provided. The cavity may be formed by a single constructional element of the LED strip fitting, thus avoiding the need for mounting a cover or side wall in front of the cavity after mounting of the LED strip in the fitting. The cavity may have a curved back wall adapted for reflecting radiation from the LED strip out of the cavity towards a viewer. The latter has the advantage of avoiding the need for partial disassembly of the LED strip fitting when a LED strip is to be installed or replaced, but results in the difficulty that the position where the LED strip is to be mounted with respect to the LED strip fitting is not directly visible by the person installing the LED strip. In other words, mounting is to be performed without direct vision on the at least one LED strip. The latter is solved in embodiments of the present invention by providing good mechanical and electrical contact by the magnetic interaction, advantageously further assisted by structural mechanical features, such as curved or cornered portions. In some embodiments of the present invention, the LED strip fitting forms a construction profile comprising at least one profile portion for receiving construction material on the profile portion. The construction profile may be a profile for finishing any of a wall, a ceiling or construction. The cavity thereby may be formed in the construction profile such that it is suitable for indirect lighting of the wall, the ceiling or the construction.
Other components that may be introduced are a heat sink for guiding the heat away from the LEDs, cooling fins, e.g. mounted on a heat sink, ... The material of the LED fitting or a part thereof may be selected such that the fitting has a good thermal behaviour for collecting heat from the LED strip and optionally dissipating it towards a heat sink.
The LED strip fitting furthermore may be adapted with an electrical connector for connecting the contact electrodes of the LED strip fitting to a power source, such as a battery or mains supply. Preferably, the LED strip fitting furthermore may be adapted for being electrically connected to neighbouring LED strip fittings. The latter can for example be obtained by adapting the LED strip fitting for contacting the at least one set of electrical contacts from a second side, thus providing the possibility to contact the at least one set of electrical contacts with an interconnection means for electrically interconnecting different LED strip fittings. Advantageously at the same time also a mechanical interconnection between different LED strip fittings can be obtained. The LED strip fitting may comprise connector spacings in which interconnection means, more particularly connection pieces, can be introduced. By providing such connector spacings at both sides of the LED strip fitting, insertion of a connector at one side of a first LED strip fitting and at another side of a second LED strip fitting, a connection between the first and the second LED strip fitting can be obtained. The connector spacing may be such that by virtue of its shape it fits with the connection pieces.
The connector spacing may comprise extruding portions and indenting portions such that the interconnection piece, or more particularly a connector portion thereof, can be received for example in a sliding manner in one direction, allowing to insert the interconnection piece in the LED strip fitting. By way of illustration, an example of a LED strip fitting 200 with a connector spacing 702 with indentations and extruding portions is shown in FIG. 7. The electrical contacts 220 from one side being electrically connectable to the LED strip and at the other side being electrically connectable with an interconnection means are also indicated, as well as the magnetic interacting element 232. Furthermore, by way of illustration, an interconnecting means is also shown in FIG. 8. The interconnection means 800 may be made of a single piece or may be made of several separate pieces. In the example shown, two connector pieces 802, 804 are provided, each connector piece 802, 804 fitting the connector spacing at one side of a LED strip fitting. The connector pieces may provide an electrical feedthrough , e.g. from one side of the connector piece to the other sied, ad may comprise an electrical socket in connection with the electrical feedthrough and adapted for receiving an electrical contact plug. Furthermore, a third portion 806 is provided for electrically interconnecting the two connector pieces, thus forming the interconnection means. Electrically interconnecting the two portions may be based on any suitable third portion, e.g. wires with electrical contact plugs for electrically contacting the connector pieces. It is to be understood that other connector pieces also can be provided, such as for example sliding electrical contact plugs. A first exemplary embodiment of a LED strip fitting according to the invention, in the present example with a LED strip according to the present invention positioned therein, is shown in FIG. 2.
The LED strip fitting 200 comprises at least one set of electrodes 220, a magnetically interacting element 232 and curved and cornered portions 234, 236 further assisting in accurate positioning when combined with complementary curved and cornered portions of the LED strip. The LED strip shown comprises the same features as described for FIG. 1B. Whereas this example shows the magnetically interacting portion and the electrical contacts in different planes of the fitting, these components also may be positioned in the same plane.
By way of illustration, particular examples are shown, whereby different examples illustrate embodiments of different aspects of the present invention. A number of LED strip fittings being at the same time construction profiles 200 will further be discussed in more detail. In a first example, a LED strip 100 is shown as well as a LED strip fitting 200, whereby direct lighting or illumination is obtained. Whereas a particular example is shown, it is obvious for the person skilled in the art that different shapes of fitting 200 and LED strips 100 are within the scope of the present invention as laid down in the appended claims.
FIG. 3A illustrates a cross section of a LED strip 100, FIG. 3B illustrates a cross section of a LED strip fitting 200 and FIG. 3C illustrates a cross section of a LED strip 100 positioned in a LED strip fitting 200. In this first example not supporting the invention, the magnetically interacting element 132 and the electrical contacts 120 are positioned in the same plane. According to an embodiment of the present invention, that magnetic interaction between the LED strip 100 and LED strip fitting 200, more particularly between the magnetically interacting element 132 and the magnetically interacting element 232 results in the pressure electrical contacts 120 being in direct contact with the electrical contacts 220 of the LED strip fitting 200. The LED strip fitting 200 shown can be used for direct lighting or illumination. In the example shown, additional features are present in the LED strip shape and LED strip fitting shape, assisting in obtaining a more accurate positioning, although embodiments are not limited thereby.
In a second example, a LED strip fitting as described above is provided, whereby the LED strip fitting comprises at least one profile portion for receiving construction material such as for example plasterboard or plaster on the profile portion, such that the LED strip fitting can be used as a construction profile for finishing any of a wall, a ceiling or a construction. By way of illustration, an example of such a profile is shown in FIG. 4A in cross section and in FIG. 4B and FIG. 4C in elevated top views, illustrating a profile that can be used for indirect lighting. In FIG. 4D a profile without LED strip is shown. In FIG. 4E an embedded construction profile is shown. FIG. 4A to FIG. 4D illustrate a LED strip fitting whereby extension profile portions 402 and 404 are suitable for receiving plasterboard material whereby portion 406 and 408 is adapted for mounting against existing construction material and wherein a cavity 410 is provided wherein the LED strip is or can be positioned. The cavity 410 may have a curved back wall 412 adapted for reflecting radiation from the LED strip out of the cavity towards a viewer. The walls of the cavity 410 may have a high reflectivity. The latter may be obtained in any suitable way, e.g. through material selection or coating. The cavity 410 is formed so that the LED strip 100 in the cavity of the profile can be positioned so that, after installation of the profile, the LED strip is not directly visible by a viewer and indirect lighting is provided in the wall, the ceiling or the construction. As mounting is to be performed without direct vision on the LED strip 100, the LED strip and LED strip fitting properties as described above are highly beneficial for these applications. The LED strip fitting may be made of any suitable material.
In FIG. 4E, an example of a similar construction profile is shown, mounted in a construction setting and illustrating how an indirect illumination is obtained. The LED strip fitting 200 is initially positioned against existing construction material 450, in the present example being wood and fixed thereto, in the present example by means of screws 452. The wall further can be finalized by providing finishing materials 460 such as plasterboard in the profile portions and by creating a finished surface using filling material 462 such as plaster. In this way a finished surface is obtained whereby, besides a flat wall, substantially only the cavity entrance 410 of the LED strip fitting is directly visible for the viewer.
In a third example, a LED strip fitting similar as the fitting shown in the second example is provided, but the LED strip fitting is adapted for forming a corner profile between two walls, a wall and a ceiling or two surfaces of a construction that are not parallel to each other. It can be seen that similar components are present, but that one portion of the profile is oriented in a different direction, in order to receive construction material from a different direction. An example of a corner profile LED strip fitting is shown in FIG. 5A to FIG. 5C, FIG. 5A to FIG. 5B illustrating the LED strip fitting in an elevated view, and FIG. 5C illustrating the LED strip fitting being mounted in a construction for finishing a corner. In one embodiment, when forming radiation lines using LED strip fittings and LED strips according to the present invention, these radiation lines typically can be build up of a plurality of LED strips. The strips thereby typically are linear strips and a curvature in an overall radiation line can be formed by varying the direction of different adjacent linear strips. In one aspect, the present invention also relates to a kit of parts comprising one or more LED strip fittings as described in the second aspect and comprising one or more LED strips for use therein, such as for example a LED strip according to the first aspect. The same features and advantages as described in the first and second aspect may be present for the parts in the kit of parts. Interconnection means as described above also can be part of the kit of parts. Disclosed below is a non-claimed method for using a LED strip fitting as described in the second aspect. More particularly, a method for using a LED strip fitting as described above for making a transition between two walls or parts thereof, between a wall and a ceiling or for finishing a construction is provided. The latter can advantageously be used for creating indirect lighting or illumination, although embodiments of the present invention are not limited thereto. The method comprises obtaining a LED strip fitting according to an embodiment as described in the second aspect and positioning profile portions of such a LED strip fitting on existing construction material. The LED strip fitting advantageously is connected, e.g. with a connector, to a power source or mains supply, so that electrical contact can afterwards be provided to the LED strip used. Alternatively, a power source may be integrated in the LED strip fitting or even in the LED strip. Typically such existing construction material will be completely hidden after the installation of the LED strip fitting. The LED strip fitting can be fixed to the existing material using e.g. screws. The method furthermore comprises providing finishing materials on profile portions adapted for receiving such finishing materials. The LED strip fitting profile may for example have profile portions adapted for receiving plasterboard. Receiving finishing materials furthermore may include using filling materials, such as for example plaster, for providing a smooth finished surface. The construction may additionally be finished, e.g. through painting, and may be prepared for use by providing a LED strip in the LED strip fitting. Similar aspects relate to replacing a LED strip from a LED strip fitting, such replacing comprising removing the LED strip from the LED strip fitting by applying a mechanical force stronger than the magnetic interaction force between the LED strip and the LED strip fitting, and positioning a new LED strip in the LED strip fitting by bringing the LED strip in the environment of the magnetic interacting element in the LED strip fitting and allowing magnetic interaction to assist in the positioning. Aspect of the invention also encompass the use of a LED strip or LED strip fitting for generating lighting or illumination, such as for example indirect lighting or illumination, and the use of a LED strip fitting for finishing a wall, ceiling or construction, e.g. for providing lighting or illumination via indirect lighting or illumination.
This method for using a LED strip fitting does not support independent claims 1 and 5. Disclosed is further a non-claimed luminaire for providing indirect illumination. Such a luminaire may be for example introduced in a wall or in a ceiling. The luminaire comprises two components, a first integratable component for building in in a construction and a second component for cooperating with the first integratable component, the luminaire comprising a set of electrodes connectable to a power supply, the second component being adapted for receiving at least one LED strip so that the LED strip is electrically connectable to the set of electrodes, the second component blocking, when cooperating with the first integratable component, direct view of the LED strip by the viewer and forming together with the first integratable component at least one cavity having a transparent outcoupling region for guiding radiation indirectly from the LED strip to the viewer.
It is an advantage of the luminaire that an indirect illumination can be obtained without the need for using a translucent material. It is a further advantage that an efficient outcoupling can be obtained. A heat sink and/or cooling fins can be provided at the first integratable component, e.g. at the backside of walls of the cavity that will be used for guiding radiation indirectly from the LED strip to the viewer. In another embodiment, a heat sink and/or cooling fins can be provided on the second component, for collecting or dissipating heat generated in or through the LED strip. The materials used for the first and or the second component may be or may at least partly be good thermal conductive materials, so that heat transport can more easily be obtained. Provision of heat sinks and/or cooling fins may be performed both on the first integratable component and on the second component.
It is an advantage that accurate cooling of components of the luminaire can be obtained as the different components can be provided with a heat sink and or cooling fins close to the heated materials without interfering with the radiation to be coupled out. The set of electrodes may be provided on the first integratable component and electrical connection of the LED strip to the first set of electrodes may be obtained when positioning the second component with respect to the first component so that these can cooperate. It is an advantage of some embodiments that no direct electrical connection needs to be provided between the second component and the mains supply. The latter allows for example a more easy installation. The transparent outcoupling region may be a transparent glass or may be an opening. It is an advantage that no translucent material is used, as the latter results in a reduction of radiation intensity or the need for stronger radiation sources.
According to the present invention, the adaptation for receiving at least one LED strip is an adaptation according to a LED strip fitting as described in the second aspect. The latter allows for accurate positioning of the LED strip in the system, without the need for screws or alike. Furthermore, a similar manner for building in the first integratable component as described for building in the LED strip fitting in the luminaire, can be applied. The second component may be either mounted to the construction so that it can cooperate with the first integratable component to form the luminaire or it may be mounted directly to the first integratable component. It may be mounted using any suitable mounting means. By way of illustration, an example of a LED strip luminaire is provided whereby the LED strip luminaire is shaped such that it can accommodate LED strips oriented in different directions. In the drawing shown in FIG. 6A to FIG. 6C a cross-sectional side view is provided of a LED strip luminaire 600 generating a rectangular shaped indirect illumination beam. The LED strip profile of the current example comprises two separate portions, one portion 610 comprising surfaces 612 for guiding the radiation indirectly to the viewer which will form at least part of the cavity, as shown in FIG. 6B and one portion 620 whereon the LED strip 100 can be mounted as shown in FIG. 6C. In the current example, the portion 620 comprising the mounting area for the LED strip 100 also comprises a heat sink 630 adjacent the LED strips when mounted and cooling fins 640 for adjusting in further cooling. In this way, a luminaire based on indirect illumination and providing an indirect radiation line for the viewer, e.g. in a closed shape, such as forming a polygonal, can be formed. The embodiments show in FIG. 3A to FIG. 3C, FIG. 6A, FIG. 6B and FIG. 7 do not support the independent claims 1 and 5.

Claims

A LED strip (100) comprising at least one light emitting device (110), the LED strip (100) further comprising
- at least one set of pressure based electrical contact electrodes (120) for electrical connection with a set of contact electrodes (220) of a LED strip fitting (200), and

- a positioning means (130) comprising on one side a magnetically interacting element (132) for positioning the LED strip (100) by magnetic interaction with the LED strip fitting (200), the magnetically interacting element (132) being adapted for providing, by magnetic interaction with the LED strip fitting (200), a pressure between the at least one set of pressure based electrical contact electrodes (120) and the contact electrodes (220) of the LED strip fitting so as to obtain electrical contact between the LED strip (100) and the LED strip fitting (200), wherein the LED strip comprises a driving module for generating drive signals for driving the LED strip (100),
wherein the positioning means (130) comprises in a cross-section perpendicular to the longitudinal direction of the LED strip (100) on said one side a curved portion (134), adapted for fitting in a complementary curved portion in the LED strip fitting (200), and a cornered portion (136) adapted for fitting in a complementary shaped portion in the LED strip fitting (200), said curved portion (134) and said cornered portion (136) extending in said longitudinal direction.
A LED strip (100) according to claim 1, wherein the driving module is adapted for receiving control data from a controller and for generating drive signals for driving the LED strip (100) based on the received control data.
A LED strip (100) according to claim 2, wherein the driving module is adapted for receiving control data from the controller via an intermediate driving module from another LED strip (100).
A LED strip (100) according to any of claims 1 to 3, wherein the driving module is an electronic circuit for converting a modulation of an incoming electronic signal to driving signals for driving the at least one light emitting device.
A LED strip fitting (200) for holding at least one LED strip (100) as defined in any of the claims 1 to 4, the LED strip fitting (200) comprising
- a cavity adapted for receiving the at least one LED strip (100) so that, after installation of the LED strip (100) in the LED strip fitting (200), the LED strip (100) is substantially not directly visible by a viewer and indirect lighting is provided,

- at least one set of contact electrodes (220) for inducing pressure based contact with the electrical contact electrodes (120) of the at least one LED strip (100),

- a magnetically interacting element (232) for magnetically interacting with the at least one LED strip (100) for positioning the at least one LED strip (100), the magnetically interacting element (232) being adapted for providing, by magnetic interaction with the at least one LED strip (100), a pressure between the at least one set of contact electrodes (220) and the contact electrodes (120) of the at least one LED strip (100) so as to obtain electrical contact between the LED strip fitting (200) and the at least one LED strip (100),
wherein the LED strip fitting (200) further comprises in a cross-section perpendicular to the longitudinal direction of the LED strip fitting (200) a complementary curved portion (234) wherein the curved portion (134) disposed on the one side of the positioning means (130) of the LED strip (100) is adapted for being fitted and a complementary cornered portion (236) wherein the cornered portion (136) disposed on the one side of the positioning means (130) of the LED strip (100) is adapted for being fitted.
A LED strip fitting (200) according to claim 5, wherein the LED strip fitting (200) furthermore comprises at least one profile portion for receiving construction material on the profile portion, the LED strip fitting (200) thus forming a construction profile for finishing any of a wall, a ceiling or construction, the cavity being formed in the construction profile such that it is suitable for indirect lighting of the wall, the ceiling or the construction.
A LED strip fitting (200) according to any of the claims 5 to 6, wherein the magnetically interacting element (232) extends along the longitudinal direction of the LED strip fitting (200).
A LED strip fitting (200) according to any of the claims 5 to 7, wherein the at least one set of contact electrodes (220) comprise two elongated electrodes along the LED strip fitting (200).
A LED strip fitting (200) according to any of the claims 5 to 8, the LED strip fitting (200) furthermore comprising at least one electrical component for driving the LED strip, the at least one electrical component being positioned at a position opposite to where the LED strip (100) is to be positioned with respect to the magnetic interacting element (232).
A LED strip fitting (200) according to any of the claims 5 to 9, wherein the fitting (200) comprises a heat sink for removing heat from the LED strip (100).
A LED strip fitting (200) according to claim 10, wherein the heat sink comprises cooling fins for cooling the LED strip fitting (200).
A LED strip fitting (200) according to any of the claims 5 to 11, wherein the LED strip fitting is adapted for contacting the at least one set of contact electrodes (220) from a side different from the side for contacting the contact electrodes (120) of the LED strip (100), thus providing the possibility to contact the at least one set of contact electrodes (220) of the LED strip fitting (200) with an interconnection means for interconnecting different LED strip fittings.
A kit of parts comprising a LED strip (100) according to any of claims 1 to 4 and a LED strip fitting (200) according to any of claims 5 to 12.