FIELD OF THE INVENTION

The invention relates to a luminaire for use with a track lighting system. The invention further relates to systems for track lighting.

BACKGROUND

Track lighting systems provide means of variably positioning and/or directing illumination; for example, according to the needs of an illuminated space. Track lighting can be used as general light in any room type, such as living room, hallways, dining room, etc., for home and/or retail applications. A typical track lighting system comprises a lighting track, one or more luminaires and at least one track lighting connector configured to connect the luminaires mechanically and/or electrically to the lighting track. The lighting track supports not only the power distribution to the luminaires but also the mechanical mounting of the luminaires at a plurality of positions (usually continuously) along their extent. Spotlights arranged via suspended tracks arranged in the ceiling are some typical examples of lighting track systems in the prior art.

Next to the typical spotlights, large area luminaires are currently more and more associated with track lighting systems. When considering mounting large area luminaires using a single track lighting connector, the safety and reliability of the track lighting system may be compromised. For example, the track lighting connector may not provide adequate support to hold the weight of the luminaire, thus, the luminaire may fall out of the lighting track, or the position of the luminaire may appear tilted with respect to the lighting track. This may impair the appearance of the track lighting system.

Hence, it is of interest to provide an improved luminaire for use with a track lighting system such that the reliability, safety and/or appearance of the track lighting system is improved.

SUMMARY OF THE INVENTION

It is an object of the present invention to mitigate the above problems and to provide a luminaire which can be securely used with a track lighting system even when having one track lighting connector.

According to a first aspect, the object is achieved by a luminaire for use with a track lighting system (100), said luminaire having a center of geometry, CG, and a center of mass, CM, said luminaire comprising: a housing (120), said housing defining a contour of the luminaire; a light emitting diode, LED, light source arranged within the housing; a track lighting connector (160) configured to mechanically and electrically connect the luminaire to a lighting track (110) of the track lighting system, said lighting track being electrically connectable to an electric supply; wherein said center of mass, CM, is different from said center of geometry, CG; wherein said track lighting connector is positioned at a connection point, C, on the housing such that a shortest distance, dl, between the connection point and the contour is smaller than a shortest distance, d2, between the connection point and the center of geometry of the luminaire; and wherein wherein a shortest distance, d3, between the connection point and said center of mass is smaller than the shortest distance, d2, between the connection point and the center of geometry.

The inventors have realized that when a luminaire is desired to be asymmetrically connected with respect to a lighting track, such as suspended (mounted) in a suspension direction from the lighting track via the track lighting connector, i.e., the connection point, C, which typically is on a top face, TF, of the luminaire, is closer to the periphery of the luminaire than to the center of geometry of the luminaire, it may be beneficial that the mass of the luminaire is not homogenously distributed across the luminaire but concentrated closer to the connection point. This is achieved with said luminaire according to the invention having its center of mass different from its center of geometry and arranging the track lighting connector at a connection point, C, on the housing such that the shortest distance, d3, between the connection point and the center of mass is smaller than the shortest distance, d2, between the connection point and the center of geometry. Typically, these distances dl, d2, and d3 are measured in a direction perpendicular to the suspension direction.

This is advantageous when luminaires are asymmetrically connected with respect to the lighting track. By having the mass (weight) of the luminaire distributed close to or around the connection point, the luminaire remains well balanced (even if the connection point is asymmetrically located with respect to the center of geometry). Thus, the mechanical and electrical connection of the luminaire with the lighting track is more reliable.

Additionally, the visual appearance of the track lighting system is improved because the luminaire may be easier arranged perpendicular to the ceiling (not tilted due to the unbalanced weight distribution).

Typically, the luminaire has only a single track lighting connector.

Preferably, the shortest distance, dl, between the connection point and the contour of the luminaire may be at least 25% smaller than the shortest distance, d2, between the connection point, C, and the center of geometry of the luminaire, CG. Such an embodiment enables more stability for luminaires asymmetrically mounted to a lighting track, for which the connection point and/or associated connector may be closer to the contour (or: edge) of the luminaire. More preferably, the connection point, C, the center of mass, CM, and the center of geometry, CG, are arranged on a straight line in a projected view along the suspension axis, F, of the luminaire (at least when considering the top, TF, and/or a bottom, BF, face of the luminaire). The bottom face is opposite to the top face which usually comprises the connection point. Typically, at least the bottom face comprises a light exit window. This provides a better aesthetic look for the hanging luminaire.

Preferably, the shortest distance, dl, between the connection point and the contour may be at least 2% of a diameter, D, of the luminaire. In other words, the connection point, C, may not be arranged exactly in the periphery (contour) of the luminaire, but, at a distance at least equal or larger than 0.02D. Here, the diameter, D, of the luminaire refers to the longest distance between two contour points. Said diameter may alternatively be phrased as the effective diameter. This is advantageous as the visual appearance of the track lighting system is improved as the connection (connection point) of the luminaire with the lighting track may not be visible by the user.

According to an embodiment of the current application, there is provided a luminaire for use with a track lighting system, wherein the luminaire may comprise a plane, E, perpendicular to the line defining the shortest distance between the connection point and the contour, said plane separating the luminaire in a first volumetric zone, A, and a second volumetric zone, B, wherein the first volumetric zone contains the center of geometry, and the second volumetric zone does not contain the center of geometry. The luminaire comprises a total weight and a total volume, and the second volumetric zone may comprise at most 15% of the total volume of the luminaire and at least 35% of the total weight of the luminaire. Hence, the total mass (weight) of the luminaire is not homogenously distributed. In fact, the density of the second volumetric zone may be higher than the first volumetric zone, preferably, at least 3 times higher than the first volumetric zone. This leads to a better- balanced luminaire as a larger percentage of the weight of the luminaire is distributed between the connection point and the periphery (contour) of the luminaire compared to the volume of that area (second volumetric zone).

The luminaire according to the current application may have a shape with at least three axes of symmetry. Preferably, there is provided luminaire having a cylindrical shape with diameter, D, equal to or larger than 40cm. Even more preferably, there is provided a luminaire having a cylindrical shape with diameter, D, equal to or larger than 100cm. In projection along a direction perpendicular to the top face, TF, and the bottom face, BF, the (cylindrical shaped) luminaire may have a circular or an elliptical or a (regular) polygonal, such as a triangular, square, hexagonal or octagonal contour or shape.

Preferably, there is provided a luminaire for use with a track lighting system, said luminaire having a length, L, a width, W, and a height, H, said height being equal to or smaller than 10% of said length and equal to or smaller than 10% of said width. Hence, preferably, there is provided a “flat” luminaire. Such a “flat” luminaire may also be referred to as a panel luminaire. Said height H is the largest distance between the top and bottom face as measured in the direction essentially perpendicular to the top and bottom face.

Preferably, there is provided a luminaire for use with a track lighting system, wherein the connection point may be located (at least partially) at the center of mass of the luminaire. Hence, the connection point may be arranged at the point where the weight of the luminaire is equally distributed on all sides of the luminaire. This is beneficial because the luminaire may have no tendency to lean in any direction and possibly tilt with respect to an elongated axis of the lighting track.

According to an embodiment of the current application, there is provided a luminaire for use with a track lighting system, wherein the luminaire may comprise a plane, E, perpendicular to the line defining the shortest distance between the connection point and the contour, said plane separating the luminaire in a first volumetric zone, A, and a second volumetric zone, B, wherein the first volumetric zone contains the center of geometry, and the second volumetric zone does not contain the center of geometry, and wherein the center of mass may be arranged within the second volumetric zone. Since the center of mass may be arranged between the connection point and the contour of the luminaire, the luminaire is more well balanced. According to an embodiment of the current application, there is provided a luminaire for use with a track lighting system, wherein the luminaire may comprise a plane, E, perpendicular to the line defining the shortest distance between the connection point and the contour, said plane separating the luminaire in a first volumetric zone, A, and a second volumetric zone, B, wherein the first volumetric zone contains the center of geometry, and the second volumetric zone does not contain the center of geometry, and wherein the luminaire may comprise one or more components being located in the second volumetric zone, B, and wherein said one or more of components may comprise at least one of: a driver, a controller and a counterweight. By arranging the heavy components (elements) of the luminaire, such as the driver, controller, counterweights, etc., in the second volumetric zone, the majority of the weight of the luminaire may be concentrated in the second volumetric zone leading to a better-balanced luminaire. According to a further embodiment of the current application, said one or more of components may comprise at least a counterweight. Such a counterweight is beneficial as it allows flexibility in arranging the weight distribution, and thus, the center of mass, of the luminaire. Preferably, the counterweight may have a density of at least 2 g/cm ² and/or a mass of at least 0.3 kg, e.g., a part of aluminum, copper and/or iron can be used.

According to an embodiment of the current application, there is provided a luminaire for use with a track lighting, wherein said luminaire may comprise a rotation means for rotating said luminaire around a suspension axis, F, said suspension axis being perpendicular to an axis of elongation of said lighting track, AE, and said suspension axis passing through the connection point, C, (such that a straight line, LI, passing through the center of geometry and the connection point, C, forms a first angle, a, with respect to axis of elongation of said lighting track). This is advantageous as it allows flexibility in the orientation of the luminaire relative to the lighting track. Preferably, the luminaire may further comprise a locking mechanism, configured to lock an orientation of the luminaire around the suspension axis, F. Typically, contour (or contour line) refers to the outline, the periphery, of the luminaire of a top view of the luminaire and/or a projected view of the luminaire when viewed in the direction of the suspension axis F.

According to a second aspect, the object is achieved by a track lighting system comprising, a lighting track being connectable to an electric supply and one or more luminaires according any one of the preceding claims, being electrically and mechanically connectable to the lighting track. Thereby, advantages and/or embodiments applying to the luminaire according to the invention may mutatis mutandis apply to said track lighting system according to the invention.

According to an embodiment of the current application, there is provided a track lighting system, wherein said one or more luminaires may comprise a plurality of luminaires, wherein said plurality of luminaires is arranged such that a straight line, LI, passing through the center of geometry and through the connection point, C, of each luminaire of the plurality of luminaires forms a different first angle, a, with respect to the axis of elongation of said lighting track. This is advantageous as it allows flexibility in individually orienting said plurality of luminaires in a lighting track system. Preferably, the contour of the luminaire has rotational symmetry of at least 180°, e.g., circular, regular polygon, etc. This is beneficial as the contour of the luminaire looks the same when the luminaire is rotated around its suspension axes, F. In an embodiment, the first angle, a, is increasing in the sequence of luminaires, for example, a first luminaire forms a first angle, a, of 0°, a second luminaire forms a first angle, a, of 60°, a third luminaire forms a first angle, a, of 90°, etc. In yet another embodiment, the track lighting system may comprise at least 4 luminaires.

According to an embodiment of the current application, there is provided a track lighting system, wherein the plurality of luminaires may be arranged at different first angles relative to the lighting track, such that the center of geometry of each luminaire of the plurality of luminaires is located on a single substantially straight line, said single straight line forming a second angle, b, with respect to the lighting track. Angle b being in the range of 10 to 40 degrees. Substantially straight meaning, in the context of this invention, of may comprise a deviation by at the most five degrees, such as at the most three degrees. This is beneficial as the visual appearance of the track lighting system is more aesthetically pleasing.

According to an embodiment of the current application, there is provided a track lighting system, wherein the track lighting system may further comprise a controller configured to receive information indicative of said first angle of each luminaire of the plurality of luminaires and control a lighting characteristic of each of said one or more luminaires based on the first angle. For example, the controller may receive signals from a camera sensing unit indicative of the orientation (first angle a between the center of geometry of each luminaire of the plurality of luminaires with respect to the axis of elongation of said lighting track) of the luminaire. In another example, the controller may receive input from a user interface, indicative of the orientation (first angle a between the center of geometry of each luminaire of the plurality of luminaires with respect to the axis of elongation of said lighting track) of the luminaire. The lighting characteristics may comprise at least one of: a light intensity, a light spectrum, a beam width, a time duration. For example, the beam width of each of the luminaires may be adjusted based on their orientation relative to the lighting track. Since the luminaires may be individually controlled based on their orientation with respect to the lighting track, the lighting track system is more flexible and versatile.

Further objectives of, features of, and advantages with, the present invention will become apparent when studying the following detailed disclosure, the drawings and the 30appended claims. Those skilled in the art will realize that different features of the present invention can be combined to create embodiments other than those described in the following.

BRIEF DESCRIPTION OF THE DRAWINGS

This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention.

Fig. 1 shows schematically a track lighting system according to an exemplifying embodiment of the present invention;

Fig. 2 shows schematically a top view of a luminaire according to an exemplifying embodiment of the present invention;

Fig. 3 shows schematically a track lighting system according to an exemplifying embodiment of the present invention;

Fig. 4 shows schematically a track lighting system according to an exemplifying embodiment of the present invention;

Fig. 5 shows schematically a track lighting system according to an exemplifying embodiment of the present invention;

Fig. 6 shows schematically a luminaire according to an exemplifying embodiment of the present invention.

All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the invention, wherein other parts may be omitted or merely suggested.

DETAILED DESCRIPTION

Fig. 1 is a schematic view of a track lighting system 100 according to an exemplifying embodiment of the present invention. The track lighting system 100 comprises a lighting track 110. The track lighting system 100 further comprises one or more luminaires 130, being electrically and mechanically connectable to the lighting track 110. The luminaire has a top face, TF, and a bottom face, BF. The luminaire 130 further comprises a housing 120, said housing defining a contour of the luminaire 130. Here, contour (or contour line) refers to the outline, the periphery of the luminaire 130 (when viewed from the top). The luminaire 130 further comprises a light emitting diode, LED, light source (not depicted) arranged within the housing 120. The luminaire further comprises a light exit window 140 arranged to exit the LED light as luminaire light. The LED light and/or luminaire light may be white light. The white light may have a correlated color temperature in a range of 2000 to 6500 K and/or a CRI of at least 80. The luminaire 130 further comprises a track lighting connector 160 configured to mechanically and electrically connect the luminaire 130 to the lighting track 110 of the track lighting system 100, said lighting track being electrically connectable to an electric supply (not depicted) and arranged to be mountable to a surface. According to this example, the luminaire has a cylindrical shape with diameter, D, and height, H. However, it should be understood that the luminaire 130 may comprise different shapes, e.g., cubic, dimensions and/or sizes than those depicted / described. Preferably, the luminaire is cylindrical with diameter, D>40cm. More preferably, the height, H, may be equal to or smaller than 10% of said diameter, D.

Fig. 2 schematically depicts a top view of the luminaire 130. The luminaire 130 comprises a center of geometry, CG, and a center of mass, CM. The center of geometry of the luminaire 130 is a point in the middle of the luminaire, i.e., the arithmetic mean position of all the points in the luminaire. For example, in a luminaire having a circular contour as in Fig. 2, the center of geometry is the middle point of the luminaire equally distant from all points in the circumference of the luminaire. In another example, when considering a luminaire in the shape of a regular polygon, the center of geometry is a point within the regular polygon equally distant from the vertices of the luminaire. The center of mass of the luminaire 130 is the point on the luminaire which represents the average mass of the luminaire. In general, the center of geometry, CM, and the center of mass, CM, may coincide when the density of the luminaire is uniform. However, the luminaire 130 in Fig. 2, has a center of mass, CM, different from the center of geometry, CG. That is, the luminaire 130 has non-uniform density.

The track lighting connector 160 is positioned at a connection point, C, on the housing 120 such that a shortest distance, dl, between the connection point and the contour is smaller than a shortest distance, d2, between the connection point and the center of geometry, CG, of the luminaire 130. In other words, the connection point, C, is arranged closer to the periphery (contour) of the luminaire 130 than the center, the middle point of the luminaire 130. A shortest distance, d3, between the connection point, C, and said center of mass, CM, is smaller than the shortest distance, d2, between the connection point, C, and the center of geometry, CG. In other words, the connection point (and thus the connector) is located closer to the center of mass of the luminaire 130 than its center of geometry.

In an example, the shortest distance, dl, between the connection point, C, and the contour is at least 25% smaller than the shortest distance, d2, between the connection point, C, and the center of geometry of the luminaire, CG. For example, in the exemplary cylindrical luminaire in Fig. 2, the connection point, C, is located at a distance, dl, at least equal or smaller than 0.2D. In a further example, the shortest distance, dl, between the connection point and the contour is at least 2% of a diameter, D, of the luminaire.

For example, in the exemplary cylindrical luminaire in Fig. 2, the connection point, C, is located at a distance at least equal or larger than 0.02D. Preferably, 0.02<dl<0.2D.

The luminaire 130 may comprise a plane, E, perpendicular to the line defining the shortest distance between the connection point and the contour, dl, said plane separating the luminaire in a first volumetric zone, A, and a second volumetric zone, B, wherein the first volumetric zone contains the center of geometry, and the second volumetric zone does not contain the center of geometry, wherein the luminaire comprises a total weight and a total volume, wherein said second volumetric zone comprises at most 15% of the total volume of the luminaire and at least 35% of the total weight of the luminaire.

In the example of Fig. 2, the center of mass, CM, is arranged within the second volumetric zone. Preferably, the connection point, C, the center of mass, CM, and the center of geometry, CG, are arranged in a single straight line in a projected view along the suspension (mounting) direction. Most preferably, the connection point, C, is located (at least partially) at the center of mass of the luminaire.

Fig. 3 is a schematic view of a track lighting system 300 according to an exemplifying embodiment of the present invention. Regarding the features and/or functions of the luminaire for use with the track lighting system 300, it is referred to Figs. 1 and 2 for an increased understanding. The track lighting system 300 comprises a lighting track 310 arranged to be mountable to a surface 320, wherein the surface 320 may constitute e.g., a ceiling, a vertical wall or a wall being inclined with respect to a ceiling (e.g., that the wall is inclined 0-90° with respect to the ceiling). The track lighting system 300 further comprises one or more luminaires 330, being electrically and mechanically connectable to the lighting track 310 with a track lighting connector 360. The luminaire 330 may further comprise a rotation means 340 for rotating said luminaire around a suspension axis, F, said suspension axis being perpendicular to an axis of elongation of said lighting track 310 and said suspension axis passing through the connection point, C.

Fig. 4 is a schematic view of a track lighting system 400 according to an exemplifying embodiment of the present invention. The track lighting system 400 comprises a plurality of luminaires 432, 434. In the example of Fig. 4, the connection point, C, is located at the center of mass, CM, of each of the luminaires 432, 434. A straight line, LI, passing through the center of geometry and through the connection point, C, of each of the luminaires 432, 434, forms a different first angle, a, with respect to the axis of elongation, AE, of the lighting track 410. In the example of Fig. 4, the first angle, a, is increasing in the sequence of luminaires, for example, the first luminaire 432 forms a first angle, a, of 30° and the second luminaire 434 forms a first angle, a, of 90°.

Fig. 5 is a schematic view of a track lighting system 500 according to an exemplifying embodiment of the present invention. The track lighting system 500 comprises a plurality of luminaires 532, 534, 536. The luminaires are arranged such that the center of geometry of each luminaire 532, 534, 536 is located on a single straight line, L2, said single straight line forming a second angle, b, with respect to the lighting track, i.e., the axis of elongation, AE, of the lighting track 510.

Fig. 6 is a schematic view of a luminaire 630 according to an exemplifying embodiment of the present invention. The luminaire 630 has a length, L, a width, W, and a height, H. Preferably, the height may be equal to or smaller than 10% of said length and equal to or smaller than 10% of said width. The luminaire 630 may further comprise one or more components 600, said one or more of components comprise at least one of: a driver, a controller and a counterweight. Preferably, the one or more components 600 may be located in the second volumetric zone, B.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.