GB2561382A

GB2561382A - Luminaire with replaceable light emitting diode light board for external use

Info

Publication number: GB2561382A
Application number: GB1705944.5A
Authority: GB
Inventors: Michael Parslow Neil
Original assignee: Light Visuals Ltd
Current assignee: Light Visuals Ltd
Priority date: 2017-04-13
Filing date: 2017-04-13
Publication date: 2018-10-17
Anticipated expiration: 2037-04-13
Also published as: GB2561382B; GB201705944D0

Abstract

A luminaire has a replaceable LED light board 3, with two fixing holes 6 having an adjacent electrically conductive part 7 connected to an LED circuit. The LED board 3 is fastened to a mounting structure 2. The fixing holes 6 are aligned with two mounting holes 5 in the mounting structure 2, and an electrically conductive connector 9, such as a bolt or screw, is pushed through each pair of holes. The connectors 9 pass through a pair of sleeves 4, extending from the mounting structure 2, and make an electrical connection with a lead 12 to deliver power to the light board. The light fitting is suitable for external use, and the sleeve may include a moisture barrier. The mounting structure may be within a housing, filled with electrically insulating packing material to render it watertight. The mounting structure may be thermally conductive, providing a heat sink.

Description

(71) Applicant(s):

(56) Documents Cited:

WO 2014/036579 A1 US 8414150 B1

DE 202007012249 U US 20070041220 A1

Neil Michael Parslow

Parkview Road, New Eltham, London, SE9 3QP, United Kingdom (58) Field of Search:

INT CL F21K, F21V Other: WPI, EPODOC

Light Visuals Ltd (Incorporated in the United Kingdom)

Parkview Road, New Eltham, London, SE9 3QP, United Kingdom (72) Inventor(s):

Neil Michael Parslow (74) Agent and/or Address for Service:

Invicta IP Ltd

18c Fairfield Road, Petts Wood, ORPINGTON, Kent, BR5 1JR, United Kingdom (54) Title of the Invention: Luminaire with replaceable light emitting diode light board for external use Abstract Title: A luminaire with replaceable LED board (57) A luminaire has a replaceable LED light board 3, with two fixing holes 6 having an adjacent electrically conductive part 7 connected to an LED circuit. The LED board 3 is fastened to a mounting structure 2. The fixing holes 6 are aligned with two mounting holes 5 in the mounting structure 2, and an electrically conductive connector 9, such as a bolt or screw, is pushed through each pair of holes. The connectors 9 pass through a pair of sleeves 4, extending from the mounting structure 2, and make an electrical connection with a lead 12 to deliver power to the light board. The light fitting is suitable for external use, and the sleeve may include a moisture barrier. The mounting structure may be within a housing, filled with electrically insulating packing material to render it watertight. The mounting structure may be thermally conductive, providing a heat sink.

Fig 6

1/2

Fig 3

Fig 4

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Fig 6

Fig 5

LUMINARE WITH REPLACEABLE LIGHT EMITTING DIODE LIGHT BOARD FOR EXTERNAL USE

Technical Field and Prior Art [ooi] The present invention relates to a luminaire assembly including a replaceable light emitting diode (LED) mounted onto a light board, and especially such a luminaire suitable for use in an external location. The invention also relate to a method of construction of the luminaire.

[002] Luminaires using LED light sources generally comprise a printed circuit light board (hereinafter known as a light board) on which one or more LED’s are surface mounted. The LED’s may be covered by a transparent lens. The light board provides conductive terminals for connection to an electrical supply. Connection of the light board has commonly been achieved by soldering the light board connectors to insulated conductors which extend through a mounting platform or chassis. The chassis is installed in a chamber formed within a housing and located behind a main lens through which light from the LED will pass. The portion of the chamber behind the mounting is then filled with a sealant, commonly a catalytically hardening resin which is intended to prevent the ingress of moisture.

Although LED’s are very durable they do eventually fail. When the LED fails in this type of luminaire the entire luminaire must be replaced since replacement of the light board in situ is practically impossible.

[003] Recycling a luminaire of this type is liable to be challenging. Furthermore where the housing is manufactured from high quality materials and of quality design, disposal and replacement of a luminaire is uneconomic and inconvenient. Even if the housing is inexpensive, process of wiring in a replacement is labour intensive, will commonly require a qualified electrician and is therefore expensive and inconvenient. Matching the original luminaire is problematic and could necessitate replacement of entire sets of luminaires to achieve aesthetic demands [004] To alleviate this problem efforts have been made to develop luminaires with replaceable light boards. Of these the most commonly used in the UK has a light board provided with a pair of pins on the side opposite the LED. The mounting structure includes a socket having two pin holes arranged to receive the pins. The light board can be replaced by the process of removing a lens housing part.

Extracting a fastening screw which retains the board, pulling the failed light board and replacing the failed board with a working board by the reverse operation. It has been found that the pins of such assemblies are not particularly easy to align with the receiving holes and are susceptible to being bent out of alignment. The light board may be retained simply by a light compression fit between the pin and the socket. In consequence the fastening screw may not be replaced due to loss, carelessness or haste resulting in premature failure caused by the light board falling out of the hole due to thermally induced strain.

[005] In US9065187B2, particularly as illustrated in figures 4 and 6E a connector is illustrated and described for a lighting board. The connector includes through passages for two electrical leads connected to the positive and negative terminals of a DC power source. Two cylindrical electrical contacts are received one each into corresponding cylindrical apertures formed into the body of the connector.

each electrical contact is fused to a conductive lead (column 5 line 31) to form an electrical connection between the lead and the electrical contact. Each electrical contact includes a bore with a female thread. The female thread is arranged to receive a conductive screw fastener received one each through corresponding holes in the light board whereby the light board circuit is electrically connected to the power supply and mechanically secured to the connector. The connector is first secured to a lighting frame (housing) of a luminaire by wings moulded onto the connector which engage with locating “L” shaped brackets by means of screws.

[006] In luminaires adapted for external applications where the luminaire is liable to encounter damp conditions it is important to thoroughly isolate the light board from the ingress of water otherwise corrosion, short circuit and other problems will arise reducing the endurance of the luminaire.

[007] It is an object of the present invention to provide a luminaire assembly with a replaceable light emitting diode light board suitable for external use which alleviates at least one of the technical problems apparent from the prior art referenced above.

Statement of Invention [008] A luminaire assembly with a replaceable light emitting diode light board suitable for external use comprising:

a mounting structure having a front surface to bear a replaceable light emitting diode light board, a pair of sleeves extending rearwardly from the mounting structure, a pair of mounting holes formed in the mounting structure coincident with the bore of each sleeve;

said lighting board including two mounting holes located to coincide one each with the bore of each sleeve, each mounting hole having a conductive part electrically communicating with a circuit including the light emitting diode, a pair of electrically conductive fasteners extending one each through each mounting hole to releasably secure, into the corresponding sleeve bore and fasten the light board to the mounting structure, and a connector structure formed in the end of the sleeve remote from the mounting structure to connect each sleeve to an electrical lead whereby a power supply is deliverable to the light board.

[009] Preferably the mounting structure is provided by a front panel having a rim with side walls extending rearwardly from the rim of the front panel to form a tubular skirt. Preferably the front panel and skirt is cylindrical. The mounting structure is preferably formed of a thermally conductive material to provide a heat sink. The thermally conductive material may be a metal such as aluminium .

[010] Where an electrically conductive material is used to provide the mounting structure a portion of each sleeve extending through holes in the front panel is electrically insulated from the front panel. This may be achieved by forming a front portion of each sleeve from an electrically isolating material.

[on] Preferably the fasteners are screws and a rearward portion of each sleeve is electrically conductive and threaded to receive and retain a light board fastening screw.

[012] The rearmost portion of each sleeve may include a diametric bore. To connect the light board to the power supply the bared end of a lead from one of the positive and negative terminals of the powersupply is threaded, one each into the rearmost end of the diametric bore of each sleeve. A screw is then driven into the threaded axial bore to engage and secure each lead.

[013] The luminaire assembly will preferably comprise a housing having a chamber into which the mounting structure is received. The housing preferably comprises a lens mounting body removably mounted onto a main body part which provides the chamber into which the mounting structure is received. Preferably the dimensions of the mounting structure and housing chamber provide a location interference fit to facilitate heat transfer from the mounting structure to the main body.

[014] Removal of the lens mounting body will expose the light board and fasteners to facilitate removal and replacement of the light board. The sleeve and mounting structure may be permanently retained in the chamber by packing the chamber with a packing material. Preferably the packing material is an insulating setting resin or foam. Preferably the packing provides a barrier to water ingress. Water may also be drawn through the insulating bores of insulator surrounding the conductor leads. To prevent this water reaching the light board each sleeve may be packed with a moisture barrier or formed with a blind bore. Apart from preventing damage to the light board this also reduces condensation forming on the inside of the main lens or on a reflector which may be provided in the lens housing part.

Brief Description of Drawings [015] An embodiment of a luminaire assembly with a replaceable light emitting diode light board suitable for external use will now be described, by way of example only, with reference to the accompanying illustrative drawings, in which:

figure 1 is an isometric SE view of the luminaire, figure 2 is an isometric NE view of the luminaire, figure 3 is a plan view of the luminaire, figure 4 is a sectional plan view of the luminaire, figure 5 is a side elevation of the luminaire with the housing parts removed, figure 6 is a sectional side elevation of the luminaire with the housing parts removed.

Detailed Description of Drawings [016] The luminaire illustrated has a mounting structure 1 having a front panel 2 to bear a replaceable light emitting diode light board 3. The light board in this case is a disc but other shapes are possible. The front panel 2 is cylindrical and a tubular wall 2’ extends rearwardly from the rim of the front panel 2. The mounting structure is fabricated from a thermally conductive metal such as aluminium or copper to provide a heat sink.

[017] A pair of similar sleeves 4 extend rearwardly from the mounting structure. A pair of mounting holes 5 extend through the front panel 2 and the front end of each sleeve 4 is received, one each into the respective holes 5.

The lighting board 3 includes two mounting holes 6 located to coincide one each with the bore of each sleeve 4. Each mounting hole 6 has a conductive rim part 7 electrically communicating with a circuit including a light emitting diode 8. A pair of electrically conductive fasteners are provided by machine screws 9 and extend one each through each mounting hole 6.

[018] Each sleeve 4 is assembled from a rearmost part 4’ a front part 4”. The rearmost part is formed from a cylindrical tube of conductive material such as copper or aluminium. A thread is cut in the bore of the part 4’ corresponding to the diameter and thread of the machine screws 9. The front part 4” is formed from a tube of electrically insulating material with a smooth bore through which the screw 9 passes unobstructed. The front part 4” electrically insulates the machine screw from the mounting 1 to prevent a short circuit. The screw 9 threadedly engages in the rear part 4’ so that the rear part is in electrical communication with the screw

9. The rear part 9 has a cross bore 10 extending diametrically through the threaded axial bore and close to the rear end of the sleeve 4. The cross bore 10 is provided to receive a conductive core 11 of a twin core lead 12 with the insulating jacket 13 stripped oft. The exposed core 11 is retained by a securing screw 14 threaded into the axial bore. The light board 3 can thereby be connected to a power source, not shown.

[019] The axial bore in the rear sleeve part 4” is closed by blind boring from each end so that a moisture barrier 4”’ is formed between the front end and rear end.

[020] The internal structure is assembled by the steps of presenting the light board 3 to the front panel 2 and inserting the screws 9. the front parts 9” of the sleeves are sleeved over the screws 9 and then the rear parts 4’ is screwed onto the screw 9.

The lead core is secured into the cross bore 10 by tightening the securing screw

14. The resulting internal structure assembly is inserted into a cylindrical main chamber 15 formed in a main body 16 of a housing. The diameter of the chamber is such that the tubular wall 2’ makes good thermal contact with the main body to provide effective heat transfer. The rear of the chamber is then filled with an insulating resin 17 which is allowed to set catalytically to form a water impermeable insulating barrier and retains the sleeves 4 and mounting 1 permanently in place. When the resin has set a protective cosmetic cylindrical cover plate 18 is secured into place in a correspondingly shaped recess 19 by means of screws 20 received into threaded holes 21.

[021] A lens mounting body 22 is fastened onto the main body 16 by means of cooperating screw threads 23 formed on each of the main body and lens body with a resilient washer 24 providing a moisture seal. The lens mounting body supports a lens 25 and reflector 26.

[022] Once assembled the light board 2 can readily be removed and replaced by unscrewing and removing the lens mounting body 22. Unscrewing the screws 9 to free the failed light board and reversing the process to restore the luminaire to function.

Claims

1. A luminaire assembly with a replaceable light emitting diode light board suitable for external use comprising:

2. An assembly according to claim 1 wherein the mounting structure is provided by a front panel having a rim with side walls extending rearwardly from the rim of the front panel to form a tubular skirt

3. An assembly according to claim 2 wherein the front panel and skirt is cylindrical.

4. An assembly according to any preceding claim wherein mounting structure is preferably formed of a thermally conductive material to provide a heat sink.

5. An assembly according to any preceding claim wherein a portion of each sleeve extending through holes in the front panel is electrically insulated from the front panel.

6. An assembly according to claim 5 wherein a front portion of each sleeve is formed from an electrically isolating material.

7. An assembly according to claim 6 wherein the rearmost portion of each sleeve includes a diametric bore to receiving a bared core of an otherwise insulated power supply lead and retained by a securing screw driven into a threaded axial bore.

8. An assembly according to claim 7 wherein the chamber is sealed by a cover.

Intellectual

Property

Office

Application No: Claims searched:

GB 1705944.5 1-11

8. An assembly according to claim 7 wherein the rear portion of the sleeve includes a moisture barrier.

9. An assembly according to claim 8 wherein the moisture barrier is formed by material remaining after blind axial bores are driven from each end of the rear portion.

10. An assembly according to any one of the preceding claims wherein the assembled mounting structure is closely received into a chamber formed in a housing and retained by filling the chamber behind the mounting structure with an electrically insulating packing material to render it watertight.

11. An assembly according to claim 10 wherein the chamber is sealed by a cover.

Amendments to the claims have been filed as follows:

08 06 18

Claims

said lighting board including two mounting holes located to coincide one each with the bore of each sleeve, each mounting hole having a conductive part electrically communicating with a circuit including the light emitting diode, a pair of electrically conductive fasteners extending one each through each mounting hole to releasably secure, into the corresponding sleeve bore and fasten the light board to the mounting structure, and a connector structure formed in the end of the sleeve remote from the mounting structure to connect each sleeve to an electrical lead whereby a power supply is deliverable to the light board, a portion of each sleeve extending through holes in the front panel is electrically insulated from the front panel, a front portion of each sleeve is formed from an electrically isolating material, the rearmost portion of each sleeve includes a diametric bore to receive a bared core of an otherwise insulated power supply lead and retained by a securing screw driven into a threaded axial bore.

08 06 18

4. An assembly according to any preceding claim wherein mounting structure is formed of a thermally conductive material to provide a heat sink.

5. An assembly according to claim 1 wherein the rear portion of the sleeve includes a moisture barrier.

6. An assembly according to claim 5 wherein the moisture barrier is formed by material remaining after blind axial bores are driven from each end of the rear portion.

7. An assembly according to any one of the preceding claims wherein the assembled mounting structure is closely received into a chamber formed in a housing and retained by filling the chamber behind the mounting structure with an electrically insulating packing material to render it watertight.