Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S4/00—Lighting devices or systems using a string or strip of light sources
  • F21S4/20—Lighting devices or systems using a string or strip of light sources with light sources held by or within elongate supports
  • F21S4/22—Lighting devices or systems using a string or strip of light sources with light sources held by or within elongate supports flexible or deformable, e.g. into a curved shape
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S4/00—Lighting devices or systems using a string or strip of light sources
  • F21S4/20—Lighting devices or systems using a string or strip of light sources with light sources held by or within elongate supports
  • F21S4/22—Lighting devices or systems using a string or strip of light sources with light sources held by or within elongate supports flexible or deformable, e.g. into a curved shape
  • F21S4/24—Lighting devices or systems using a string or strip of light sources with light sources held by or within elongate supports flexible or deformable, e.g. into a curved shape of ribbon or tape form, e.g. LED tapes
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
  • H05B45/40—Details of LED load circuits
  • H05B45/44—Details of LED load circuits with an active control inside an LED matrix
  • H05B45/48—Details of LED load circuits with an active control inside an LED matrix having LEDs organised in strings and incorporating parallel shunting devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
  • F21V23/00—Arrangement of electric circuit elements in or on lighting devices
  • F21V23/001—Arrangement of electric circuit elements in or on lighting devices the elements being electrical wires or cables
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
  • F21V23/00—Arrangement of electric circuit elements in or on lighting devices
  • F21V23/06—Arrangement of electric circuit elements in or on lighting devices the elements being coupling devices, e.g. connectors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
  • F21V3/00—Globes; Bowls; Cover glasses
  • F21V3/04—Globes; Bowls; Cover glasses characterised by materials, surface treatments or coatings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
  • F21Y2107/00—Light sources with three-dimensionally disposed light-generating elements
  • F21Y2107/30—Light sources with three-dimensionally disposed light-generating elements on the outer surface of cylindrical surfaces, e.g. rod-shaped supports having a circular or a polygonal cross section
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
  • F21Y2107/00—Light sources with three-dimensionally disposed light-generating elements
  • F21Y2107/70—Light sources with three-dimensionally disposed light-generating elements on flexible or deformable supports or substrates, e.g. for changing the light source into a desired form
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
  • F21Y2115/00—Light-generating elements of semiconductor light sources
  • F21Y2115/10—Light-emitting diodes [LED]

Definitions

• Elongated flexible lighting device based on solid-state lighting technology
• the present invention relates to an elongated lighting device which is flexible and based on solid-state lighting (SSL) technology.
• SSL solid-state lighting
• Light-emitting diode (LED) strips formed by a flexible flat substrate with surface-mounted LEDs are widely used in many applications, for example cove lighting, wall washing and other decorative lighting applications.
• LED Light-emitting diode
• a factor that limits their applicability is that they are typically only easily flexible out of the plane of the substrate, the in-plane stiffness of the substrate being too high to allow extensive in-plane bending.
• Various attempts have been made to provide lighting devices that are easily flexible in several directions an example being the lighting device disclosed in US 2005/0162850 Al . That lighting device has a flexible cylindrical tube inside which a helically wound LED strip with a stiffening wire is arranged.
• a lighting device comprising: an elongated flexible core having a polygonal transverse cross section; and a flexible circuit strip having several SSL elements mounted thereon, the flexible circuit strip being helically wound around the core.
• the present invention is based on the realization that one way of overcoming the problem that flexible circuit strips are generally not flexible in the plane of the strip is to form the circuit strip into a helix and to arrange the helix around a flexible core.
• the above- described lighting device which is designed in that way, can be easily and extensively flexible in several directions.
• the lighting device may for example be adapted so as to be bendable in at least two non-parallel directions. It is also possible to produce the above- described lighting device in a relatively fast, simple and inexpensive manner.
• the core greatly facilitates the helical winding of the circuit strip, and the fact that the cross section of the core is polygonal facilitates accurate positioning of the SSL elements and thus the provision of a light distribution that is not omnidirectional. For example, a light distribution that equals the beam angle(s) of the SSL elements is easy to provide using such a core.
• the cross section of the core may have the shape of a regular or an irregular polygon. Examples of cross sections include, but are not limited to, cross sections that are triangular, rectangular, pentagonal, hexagonal or heptagonal. All of the SSL elements may be arranged on a single longitudinal side of the core. In that way all of the SSL elements may be oriented so that all of them have the same general direction of illumination.
• the SSL elements may be arranged on several longitudinal sides of the core. In that way the SSL elements may be oriented so that the lighting device is capable of emitting light in several general directions of illumination.
• the core may have a modulus of elasticity in the range from 0.001 GPa to 1 GPa, for example from 0.1 GPa to 1 GPa, and/or a yield strength in the range from 5 MPa to 50 MPa, for example from 25 MPa to 50 MPa.
• the core can for example be made of a plastic material. Examples of core materials include PUR (foam), PVC and silicone.
• the lighting device may comprise a flexible light-transmissive housing inside which the core and the flexible circuit strip are arranged.
• the housing may for example be translucent or transparent.
• the housing may be adapted to control the light distribution. By combining such a housing with a polygonal core it is possible to control the direction of the light emitted by the lighting device to a particularly high degree.
• the housing may for example have a lens shape.
• the housing may have a modulus of elasticity in the range from 0.001 GPa to 1 GPa, for example from 0.1 GPa to 1 GPa, and/or a yield strength in the range from 5 MPa to 50 MPa, for example from 25 MPa to 50 MPa.
• the housing can for example be made of PVC or silicone.
• the lighting device may comprise a first set of connectors which are mounted on the flexible circuit strip and which are adapted for electrically connecting the SSL elements to a power supply.
• the first set of connectors can be used as aligning features to make sure that the SSL elements are correctly aligned/oriented.
• the first set of connectors and the SSL elements can be arranged on different sides of the core.
• the lighting device may comprise a wire which electrically connects the first set of connectors to each other and which extends along a side of the core where the first set of connectors are arranged.
• the lighting device may comprise a second set of connectors which are mounted on the fiexible circuit strip and which are adapted for electrically connecting the SSL elements to a power supply. Like the connectors of the first set, the connectors of the second set can be used as aligning features. Moreover, the second set of connectors may provide redundancy. The second set of connectors may be arranged on a different side of the core than the first set of connectors and the SSL elements. The lighting device may comprise a wire which electrically connects the second set of connectors to each other and which extends along a side of the core where the second set of connectors are arranged.
• a method for producing a lighting device comprising: providing an elongated flexible core having a polygonal transverse cross section; providing a flexible circuit strip having several SSL elements mounted thereon; and helically winding the flexible circuit strip around the core.
• the step of helically winding the flexible circuit strip around the core may comprise arranging all of the SSL elements on a single side of the core.
• the step of helically winding the flexible circuit strip around the core may be performed in such a way that the SSL elements end up being positioned on a single side of the core.
• the step of helically winding the flexible circuit strip around the core may be performed in such a way that the SSL elements end up being positioned on two or more sides of the core.
• the method may comprise: overmolding the flexible circuit strip and the core to form a flexible light-transmissive housing; or inserting the flexible circuit strip and the core into a pre-formed flexible light-transmissive housing.
• the overmolding can for example be performed by co-extrusion.
• FIG. 1 shows a perspective view of a lighting device according to an embodiment of the invention.
• Fig. 2 shows a cross sectional view along line X-X in Figure 1.
• Fig. 3 shows a flowchart of a method for producing the lighting device in Figures 1 and 2.
• Figures 1 and 2 show a lighting device 1 which is suitable for use in applications such as, for example, cove lighting, wall washing, signage and architectural lighting.
• the lighting device 1 is elongated.
• the lighting device 1 is shown in a straight configuration and defines a longitudinal direction L.
• the length 1 of the lighting device 1 in the longitudinal direction depends on the application, but is typically in the range from 5 m to 10 m.
• the width w of the lighting device 1 is typically in the range from 10 mm to 20 mm.
• the height h of the lighting device 1 is typically in the range from 10 mm to 15 mm.
• the lighting device 1 has a central elongated flexible core 2, henceforth referred to as the "core" for brevity.
• the major extension of the core 2 is in the longitudinal direction L.
• the core 2 is capable of flexing in any direction perpendicular to the longitudinal direction L. Differently stated, the core 2 is bendable in any direction perpendicular to the longitudinal direction L.
• the core 2 is in this case made of a plastic material with a low modulus of elasticity and a high yield strength.
• the core 2 has the shape of a prism, more precisely a rectangular prism.
• the cross section of the core 1 , transverse to the longitudinal direction L, is substantially rectangular, and the core 2 has four flat outer side surfaces extending in the longitudinal direction L. The side surfaces are pairwise oppositely arranged.
• the core 2 is a hollow tube and may thus be referred to as a core tube. In a different example the core 2 may be solid.
• the flexible circuit strip 3 will in the following be referred to as the "strip" for brevity.
• the strip 3 follows the contour of the core 2 in a helical path in the longitudinal direction. This means that the strip 3 has the shape of a helix, the axis of which is parallel with the longitudinal direction L.
• the strip 3 includes electrical circuitry for electrically connecting the SSL elements 4 (further discussed below).
• the strip 3 may for example be formed by a flexible plastic substrate on which a conductive pattern has been printed.
• the strip 3 is wound around the core 2 so that there is a longitudinal gap, or space, between consecutive portions of the strip 3.
• the gap follows a helical path in the longitudinal direction L.
• the width d of the gap is typically in the range from 0.1 mm to 1 mm. The gap facilitates movement of the strip 3 during bending of the lighting device 1.
• SSL elements 4 are mounted on and electrically connected to the strip
• the SSL elements 4 are adapted to emit light.
• Each SSL element 4 includes one or more light sources, such as semiconductor LEDs, organic LEDs, polymer LEDs, or laser diodes. All of the SSL elements 4 may be configured to emit light of the same color, for example white light, or different SSL elements 4 may be configured to emit light of different colors.
• the SSL elements 4 are arranged in a row in the longitudinal direction L. It should be noted that even if the illustrated SSL elements 4 are aligned with each other, they could be arranged in for example a zigzag pattern in a different example. All of the SSL elements 4 are arranged along the same side of the core 2 (the top side in Figure 1). Further, the SSL elements 4 are oriented so that, when the lighting device 1 is in the straight configuration illustrated in Figure 1, all of the SSL elements 4 have the same general direction of illumination. The general direction of illumination is in this case perpendicular to the longitudinal direction L.
• SSL elements 4 it is not necessary that all of the SSL elements 4 be oriented so as to emit light in the same general direction. In a different example (not shown), different SSL elements 4 may be oriented to emit light in different directions. For example, instead of all of the SSL elements 4 being positioned on the core's 2 top side, there may, alternatively or in addition, be SSL elements positioned on the core's 2 bottom side and/or lateral side(s). In this way the lighting device 1 may be adapted to emit light in two or more directions.
• a first set of connectors 5 are mounted on the strip 3 and electrically connected to the SSL elements 4.
• the first set of connectors 5 are arranged in a row in the longitudinal direction L.
• the connectors 5 in the first set are aligned with each other.
• the first set of connectors 5 are arranged along a different side of the core 2 than the SSL elements 4, a lateral side in Figure 1.
• the first set of connectors 5 may for example be SMT crimp contacts, like the Harwin S1721-06R.
• the connectors 5 in the first set are typically equidistant ly arranged in the longitudinal direction L.
• the longitudinal distance between the connectors 5 in the first set may for example be in the range from 10 mm to 20 mm.
• the first set of connectors 5 are electrically connected to each other by a first wire 6 for providing electrical power to the SSL elements 4.
• the first wire 6 is in this case a main bus wire adapted to carry a current from an electric power supply, such as the mains electric power supply, via an LED driver (not shown).
• a second set of connectors 5 ' are mounted on the strip 3 and electrically connected to the SSL elements 4.
• the second set of connectors 5' are arranged in a row in the longitudinal direction L.
• the connectors 5' in the second set are aligned with each other.
• the second set of connectors 5 ' are arranged along a different side of the core 2 than the SSL elements 4 and the first set of connectors 5', a lateral side in Figure 1.
• the first set of connectors 5 and the second set of connectors 5' are arranged on opposite sides of the core 2.
• the connectors 5' in the second set are typically of the same type as the connectors 5 in the first set.
• the connectors 5' in the second set may be SMT crimp contacts, like the Harwin S1721-06R.
• the connectors 5 ' in the second set of connectors are typically equidistantly arranged in the longitudinal direction L.
• the longitudinal distance between the connectors 5' in the second set may for example be in the range from 10 mm to 20 mm.
• the second set of connectors 5' are electrically connected to each other by a second wire 6' for providing electrical power to the SSL elements 4.
• the second wire 6' is in this case a main bus wire adapted to carry a current from an electric power supply, such as the mains electric power supply, via an LED driver (not shown).
• the connectors 5, 5' may depend on the pitch of solder pads on the strip 3 and the diameter and the pitch of the helix.
• the lighting device 1 further comprises an outer housing 7.
• the housing 7 has a hollow tubular shape.
• the shape of the housing 7 may alternatively be referred to as hollow and cylindrical.
• the housing 7 has an interior space, and the core 2, the strip 3 with the SSL elements 4, the connectors 5, 5' and the wires 6, 6' are arranged in the interior space of the housing 7. These components are thus arranged inside the housing 7.
• the housing 7 is light-transmissive and flexible.
• the housing 7 is capable of flexing in any direction perpendicular to the longitudinal direction L.
• the housing 7 is bendable in any direction perpendicular to the longitudinal direction L.
• the housing 7 is in this case made of a plastic material with a low modulus of elasticity and a high yield strength.
• the lighting device 1 usually comprises additional components not shown in Figures 1 and 2, such as one or more drivers for the LEDs and end caps for connecting the lighting device 1 to a mains electric supply and/or to other lighting devices.
• the end caps may for example form a housing for the driver(s).
• the lighting device 1 is put in operation by connecting it to an electricity supply so that power is supplied to the SSL elements 4 via the driver(s), the wires 6, 6', the connectors 5, 5' and the strip 3.
• the SSL elements 4 emit light that is transmitted through the housing 7.
• the lighting device 1 may be produced by the method schematically illustrated in Figure 3, i.e. by first, in steps SI and S2, providing the core 2 and the strip 3 with the SSL elements 4, and then, in step S3, helically winding the strip 3 around the core 2.
• the SSL elements 4 of the illustrated lighting device 1 are positioned on the same side of the core 2, and this may be achieved by helically winding the strip 3 around the core 2 in the appropriate manner.
• the housing 7 may be formed by overmolding the strip 3 and the core 2.
• the housing 7 may be pre-formed separately, whereafter the strip 3 and the core 2 are inserted thereinto.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Arrangement Of Elements, Cooling, Sealing, Or The Like Of Lighting Devices (AREA)
• Non-Portable Lighting Devices Or Systems Thereof (AREA)
• Fastening Of Light Sources Or Lamp Holders (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=58668756

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (2)

Citations (8)

Family Cites Families (18)

• 2018
  • 2018-04-24 EP EP18718838.8A patent/EP3619462B1/en active Active
  • 2018-04-24 US US16/610,137 patent/US10808895B2/en active Active
  • 2018-04-24 JP JP2019560100A patent/JP7096269B2/ja active Active
  • 2018-04-24 WO PCT/EP2018/060464 patent/WO2018202480A1/en not_active Ceased
  • 2018-04-24 CN CN201880029075.9A patent/CN110582668B/zh active Active

Patent Citations (8)

Also Published As

Similar Documents

Legal Events