"An Illuminator"

INTRODUCTION

Field of the Invention

The invention relates to illuminators for applications including, for example, display cases or cabinets.

At present, illuminators for applications such as retail display cases give rise to problems including having high power consumption, and/or unreliability due to failure of incandescent and fluorescent light sources, and/or costly maintenance, and/or difficulty of retrofitting to existing display cases or cabinets.

The invention addresses these problems.

Another object is to provide an illuminator which is more versatile to manufacture in the factory or to customise on site during installation.

SUMMARY OF THE INVENTION

According to the invention, there is provided an illuminator assembly comprising an illuminator having a housing and at least one light emitting diode mounted on a substrate within the housing, and an illuminator support for mounting the illuminator in a goods cabinet,

wherein the illuminator is of elongate shape, and

wherein the illuminator support comprises at least one bracket for fitting to a planar goods cabinet shelf or shelf support, the bracket being configured to straddle the shelf or shelf support at an edge thereof and including a support means to engage the housing to support the illuminator.

In one embodiment, the housing comprises a housing body of elongate material, and end caps secured to the ends of the housing body.

In one embodiment, the housing comprises a platform for the substrate.

In one embodiment, the housing comprises at least one receiver for fasteners securing the substrate on the platform, the fastener receiver comprising a channel extending along the length of the housing.

In one embodiment, the channel comprises side ridges along its length for engagement with screw fastener threads.

In a further embodiment, the housing comprises a base of thermally-conductive material under the substrate to provide a heat transfer path for heat from the substrate.

In one embodiment, the illuminator further comprises a heat transfer material between the substrate and the platform.

In one embodiment, the housing comprises heat transfer fins.

In another embodiment, the fins are substantially parallel and fit within an overall curved outer periphery configuration.

Ih one embodiment, the cross-sectional shape of the housing is substantially circular.

In one embodiment, the illuminator further comprises a cover over the diodes.

In one embodiment, the cover is of flexible material, retained in its shape by engaging the housing on opposed sides.

In one embodiment, the housing comprises a pair of opposed grooves to receive and retain opposed side edges of the cover.

In one embodiment, the grooves are configured to allow manual removal and reinsertion of the cover.

In a further embodiment, the cover is of transparent plastics or polymer material.

In one embodiment, the substrate comprises modular substrate parts with end terminals for inter-connection.

In one embodiment, the diodes comprise diodes of different types to achieve a desired illumination effect.

In one embodiment, the bracket is of U-shaped configuration, having a pair of opposed flanges interconnected by a web, said flanges being configured for gripping a planar shelf or shelf support on opposed surfaces.

In one embodiment, the support means allows the housing to be rotated.

In one embodiment, the bracket support means allows the housing to be rotated through 360°.

In one embodiment, the support means comprises a seat for an end of the illuminator.

In one embodiment, the seat comprises a pair of opposed receivers, and the illuminator comprises a flange for engaging in the receivers.

In a further embodiment, the receivers are inclined downwardly and inwardly towards each other.

In one embodiment, the support means comprises an annular support configured to receive an end of the housing.

In one embodiment, the illuminator comprises a flange on a sleeve-shaped coupler secured to a housing main body, said flange being for engagement with the support means.

In one embodiment, there is a circumferential groove behind the flange, and the support means engages in the groove.

In one embodiment, the illuminator further comprises a lock for preventing sliding movement of the bracket.

In one embodiment, the lock comprises a pin engaging the shelf support.

In another aspect, the invention provides an illuminator comprising:

an elongate housing body having a support platform,

light emitting diodes mounted on a substrate, in turn mounted on said platform,

the housing body having a base of thermally-conductive material below the platform and extending along the length of the housing body, said base terminating in heat dissipation fins,

said housing body having a pair of opposed grooves over the substrate, and a resilient transparent cover over the diodes and being snap-fitted in place with opposed edges engaging in said grooves, and

an end cap secured to each end of the housing body.

In one embodiment, the illuminator has a substantially circular cross-sectional shape.

In one embodiment, the illuminator further comprises a circular flange at each end of the illuminator, said flange being configured for engagement with a support means in a manner which allows rotation about a longitudinal axis of the illuminator.

In another aspect, the invention provides a method of manufacturing any illuminator as defined above, the method comprising the steps of:

cutting a length of extruded housing body extrusion material to provide the housing body with a desired length,

cutting a length of cover material to provide the cover with a desired length,

providing at least two modular light emitting diode substrates, and interconnecting them on the platform of the housing body,

snap-fitting the cover in place between the opposed grooves, and

securing the end caps to the ends of the housing body.

In one embodiment, the housing body has a channel running along the length of the platform, and the substrate is secured in place by fastening screws at appropriate locations along the channel.

Detailed Description of the Invention

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: -

Fig. 1 is a perspective view from above of an illuminator of the invention, and Fig. 2 is a perspective view from behind;

Figs. 3 (a) and (b) are diagrammatic cross-sectional views through the illuminator, showing the configuration of a housing body and how an LCD substrate PCB is secured to it;

Fig. 4 is a perspective view of an end cap for the housing;

Fig. 5 is a perspective view of the illuminator during manufacture with mounting fixtures attached;

Figs. 6, 7, and 8 are perspective, end, and side views respectively of a straddle bracket for mounting the illuminator onto conventional shelf supports;

Figs. 9 and 10 are perspective views showing the illuminator being mounted onto the shelf support;

Fig. 11 is an end view showing an illuminator supported by the brackets; and

Figs. 12 and 13 are side and front views showing an alternative illuminator and bracket of the invention.

Description of the Embodiments

Referring to the drawings an illuminator 1 is of elongate overall configuration, generally similar to that of a conventional illuminator of the fluorescent tube type. The illuminator 1 comprises a housing body 2 which is a section of a length of extruded aluminium. A transparent polymer cover 3 is snap-fitted in place across a front opening of the housing body 2. There is an end cap 4 at each end of the housing body 2, secured in place by screws into the end faces of the housing 2.

A circuit board 5 is supported on the housing 2, and it is a substrate for LEDs 6 and drive circuits 7.

As shown most clearly in Figs. 3 (a) and 3(b) the housing body 2 has a supporting platform 9 for the PCB 5. A channel 10 runs centrally along the length of the housing body 2, acting as a guide and receiver for screws 11 to secure the PCB 5 to the housing body 2. The channel 10 comprises ridges along each side, allowing secure engagement of the screw threads. There is a heat transfer pad 18 between the board 5

and the housing platform 9, allowing optimum thermal contact. Alternatively, there may be a different thermally conductive material such as thermally conductive greases or rubber. If there is a pad, it may have an adhesive.

This arrangement presses the board 5 against the housing 2 so that there is optimum heat transfer from the underside of the board 5 into the housing 2. It also allows the illuminator to be easily assembled during manufacture, and for the PCB to be removed and replaced for any maintenance or upgrade that may be required during its lifetime. Also, there is no need for pre-drilling in the housing 2 for the screws 11 as the channel 10 provides a sufficient guide for engaging screws at any position.

The housing 2 comprises a base 12 for physical support of the board 5, for overall strength, and for heat transfer. Heat transfer pads 18 and integral fins 13 complete a heat transfer path to the surrounding environment. The edges of the fins are rounded to avoid sharp edges.

The housing body 2 also comprises longitudinal grooves 14 on each lateral side at the front for retaining the transparent cover 3. Because the cover is flexible, it can be easily snap-fitted into position. This allows the cover 3 to be easily fitted . during manufacture and to be fitted and removed during the lifecycle of the illuminator. In another embodiment, there is less flexibility in the cover.

It will be appreciated from Figs. 3 (a) and 3(b) that the internal surfaces of the housing surrounding the PCB 5 will reflect some light from the LEDs 6, thus optimising the extent of light output and also allowing significant control over the directionality of the light according to the shape of the housing 2. The shape of the housing may be different from that illustrated in order to achieve a different light output pattern with a different extent of reflection from the internal surfaces.

Fig. 4 shows an end cap 4 in more detail. It will be noted that there is a ledge 15 for additional support of the board 5, fixing screw apertures 16, and an aperture 17 for electrical cable 20 for the board.

It will also be appreciated from the drawings that the illuminator may be manufactured with excellent versatility in terms of its length. One must only cut the extruded aluminium housing body 2 to the desired section length and cut the plastics cover 3 accordingly. The PCB 5 is in modular sections with terminals for interconnection. Indeed it is envisaged that the illuminator may even be customised on site to suit the display case into which it is being fitted.

Referring to Fig. 5 the illuminator 1 also comprises mounting couplers 25 secured by grub screws. Each coupler 25 is of tubular shape, and at its outer extremity there is a circumferential groove 26 defining an end flange 27. The cable 20 is trained through the coupler 25.

The couplers 25, together with straddle brackets 30, allow the illuminator to be easily and securely mounted onto conventional shelf supports or brackets B, for retrofitting or original installation. As shown in Figs. 6 to 8 inclusive each straddle bracket 30 comprises a top web 31 and two downwardly-depending flanges 32, forming together an inverted U-shaped configuration. The flanges 32 have corresponding vertical slots 33 to accommodate the cable 20. Also, there is a pair of receivers 34 and 35 on each flange 32, together forming a seat. Each receiver extends at an angle between vertical and horizontal tapered downwardly towards each other. Each receiver 34, 35 comprises a pressed-out length of the bracket metal forming a slot to receive the end flange 27.

Referring to Figs. 9, 10, and 11 on one side of a straddle bracket 30 the pair of receivers 35 together form a seat to receive the flange 27 of a coupler 25. Because of the angles at which the receivers 34 and 35 are inclined they form a particularly stable seat for the ends of the illuminator 1, and furthermore they allow the illuminator to be rotated for optimum direction of the light. The illuminator further comprises a fixture which is secured to the shelf support B by engagement of a pin in an aperture of the shelf support. This is secured in place at a location to prevent sliding of a straddle bracket 30.

It will also be appreciated that the sleeve-shaped couplers 25 and the straddle brackets 30 allow the illuminator to be easily and quickly mounted in a display cabinet having conventional shelf supports or brackets B, allowing very easy retrofitting. What has been achieved is excellent illuminator support stability, versatility for rotation to a desired illumination direction, and very simple fitting/installation either retrofitted or original. Fig. 11 in particular shows how the top web 31 of the bracket 30 is matched in height by a fixture 40 over the shelf support B to ensure horizontal mounting of the shelf S.

The illuminator, when installed, can be rotated to any desired orientation so that it may for example illuminate items on a shelf underneath it. Alternatively, it may be upwardly directed to illuminate items above it through a glass shelf supported on the shelf support brackets.

Another advantage of the illuminator is that the manufacturer can easily choose illumination parameters by simply choosing the desired configuration of modular boards 5. For example, there may be a specific chosen pattern of different LEDs to achieve a particular illumination effect. Another versatile parameter is the length of the housing body 2, and hence of the illuminator.

It will be appreciated that the illuminator has a similar physical configuration to a conventional fluorescent illuminator, allowing the latter to be replaced with illuminators which do not give rise to hazardous waste disposal issues. Indeed, it is envisaged that, in another embodiment, the illuminator may be configured to fit into a support and power supply of a conventional fluorescent illuminator. Thus the illuminator may be supplied as a plug-in replacement for a fluorescent tube, with the fluorescent tube electrical supply providing power to the circuit. The power supply may be mains or down-converted AC or DC depending upon the illumination requirements. This embodiment may include a safety feature for by-passing or disconnecting a ballast to ensure that high voltages are not applied.

In use, it is preferable that a pair of opposed straddle brackets 30 supports an illuminator, however with suitable configuration of the brackets and couplers (and

possible size and weight of housing) a single straddle bracket may provide cantilevered support. This allows further versatility.

It is also envisaged that the illuminator may form part of a frame of a display case, such as a mullion.

Referring to Figs. 12 and 13 in another embodiment a bracket 50 has a U-shaped shelf edge surround 51 for straddling the front edge of a shelf S and a screw 52 to secure the bracket 51 in place. The lower flange of the surround 51 is secured to a depending and circular illuminator support 53 through which the illuminator coupler 25 fits. Again, this allows the illuminator to be easily retro-fitted to an existing cabinet, and to be rotated to an optimum illumination position.

In a further embodiment, an illuminator support may have a bracket similar to the bracket 50, but the support means may be similar to the arrangement in the bracket 30, with opposed cut-outs or grooves forming a seat for the ends of the illuminator.

The invention is not limited to the embodiments described but may be varied in construction and detail. For example, the illuminator may not include any support. In this embodiment, it may for example be the equivalent of a replacement "bulb". Where there is a support, it may be of any other suitable configuration.