INTRODUCTION Field of the Invention

The invention relates to a linear LED illuminator having an elongate housing and an end cap at one or both ends for an auxiliary component such as a sensor or an auxiliary light emitter.

Prior Art Discussion

Our prior PCT Patent Specification No. WO2015/110455 describes such an illuminator.

EP3196549 (Zumtobel) describes an elongate illuminator in which access is provided to the housing by pivoting end caps. US2013/0094225 (Ecosense) describes a linear illuminator having removable end caps.

An object of the invention is to provide an illuminator of this type in which there is improved versatility in the auxiliary components and also ease of access to the auxiliary components and for example electrical connectors.

Summary of the Invention

We describe an LED illuminator comprising an elongate housing having a transparent wall for light emission and LEDs on a substrate in said housing and at least one end cap comprising an end cap housing arranged to engage an end of the elongate housing, and a cover) to the end cap housing, allowing access to space within the end cap housing.

Preferably:

the cover is pivotally connected to the end cap housing by a hinge, and/or

there is a resilient seal between the cover and the housing, and/or

there is a cover fastener for securing the cover to the end cap housing.

Preferably, the cover is over a longitudinal face of the end cap housing on a light-emitting side of the illuminator. Preferably, the hinge has an axis extending transversely across the illuminator. Preferably, the hinge is across an inner end of the end cap housing, closest to the elongate housing.

The hinge may be configured to allow the cover to hang down when open and facing downwardly. Preferably, the hinge allows the cover to be removable and comprises a part on the end cap housing and an inter-engaging part of the end cap cover. Preferably, one part comprises a groove and the other part comprises a bar or axle configured to fit within the groove. Preferably, the groove is open-ended. The axle may be supported by end supports arranged to fit beyond each end of the groove.

Preferably, the cover fastener includes a lockable fastener. The lockable fastener may comprise a tab in one of the cover or end cap housing arranged to engage in a seat of the other of the cover and end cap housing. Preferably, the cover fastener comprises at least one snap fit fastener or latch. Preferably, the end cap housing has an integral end wall. The integral end wall may include an opening to receive a cable for power or data and the end cap includes terminals for connection to such cables. Preferably, the opening includes a gland.

The cover may include at least two spaced-apart retainers extending from an inner surface of the cover, said retainers being configured to retain a component within the end cap, and to expose the component when the cover is open.

Preferably, there is a resilient seal for engagement of the end cap housing with the elongate housing. Preferably, at least one end cap cover is configured to support an exposed auxiliary component.

Preferably, the end cap cover includes a threaded support extending through the cover and configured to be retained by a nut engaging threads on the inside of the cover and to engage the auxiliary component on the outside of the cover.

The threaded support may be of metal to act as a heat sink for an auxiliary component. Preferably, the threaded support comprises external threads for engaging the nut and internal threads for engaging an auxiliary component.

Preferably, said auxiliary component includes an emergency light emitter. Preferably, the elongate housing includes a pair of opposed internal grooves supporting a partition wall between an elongate chamber for electrical connectivity components and an elongate chamber for the LEDs.

The partition wall may comprise at least one pair of longitudinal grooves retaining an LED substrate.

Preferably, the elongate housing comprises a pair of opposed external lips or grooves supporting luminaire mounting brackets.

Additional Statements

According to the invention, there is provided an LED illuminator comprising:

an elongate housing having a transparent wall for light emission and containing LEDs on a substrate;

at least one end cap comprising:

an end cap housing arranged to engage an end of the elongate housing, a cover to the end cap housing, allowing access to space within the housing. In one embodiment, the cover is hinged to the end cap housing. In one embodiment, the cover is over a longitudinal face of the end cap housing. In one embodiment, the cover hinge has an axis extending transversally across the illuminator. In one embodiment, the hinge is across an inner end of the end cap housing, closest to the elongate housing. In one embodiment, the hinge allows the cover to hang down when open. In one embodiment, the hinge is removable and comprises a part on the end cap housing and an inter-engaging and part of the end cap cover. In one embodiment, one part comprises a groove and the other part comprises a bar or axle configured to fit within the groove. In one embodiment, the groove is open-ended. In one embodiment, the axle is supported by end supports arranged to fit beyond each end of the groove. In one embodiment, the cover is lockable. In one embodiment, the end cap housing has an integral end wall.

In one embodiment, the integral end wall includes an opening to receive a cable for power or data. In one embodiment, the opening includes a gland. In one embodiment, the cover includes at least two spaced-apart retainers extending from an inner surface of the cover, said retainers being configured to retain a component within the end cap, and to expose the component when the cover is open.

In one embodiment, there is a resilient seal for engagement of the cover with the end cap housing. In one embodiment, there is a resilient seal for engagement of the end cap housing with the elongate housing. In one embodiment, at least one end cap cover is configured to support an exposed auxiliary component. In one embodiment, the end cap cover includes a threaded clamp extending through the cover and configured to be retained by a nut engaging the threads on the inside of the cover. In one embodiment, said auxiliary component includes an emergency light emitter. In one embodiment, the elongate housing includes a pair of opposed internal grooves supporting a partition wall between an elongate chamber for electrical connectivity components and an elongate chamber for the LEDs.

In one embodiment, the partition wall comprises at least one pair of longitudinal grooves retaining an LED substrate.

In one embodiment, the elongate housing comprises a pair of opposed external lips or grooves supporting luminaire mounting brackets. DETAILED DESCRIPTION OF THE INVENTION

Brief Description of the Drawings

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 of an illuminator of the invention;

Fig. 2 is a cut-away perspective view showing mounting of components within the elongate housing; Fig. 3 is a perspective view of an end of the illuminator, showing an end cap when open; Fig. 4 is a perspective view, showing detachment of an end cap cover;

Fig. 5 is an exploded view of mounting of an auxiliary, emergency, light emitter on an end cap cover;

Fig. 6 is a view into an end cap with the cover removed; and

Fig. 7 is a diagrammatic longitudinal sectional view of the illuminator. Description of the Embodiments

Referring to Fig. 1 an illuminator 1 comprises an elongate housing 10 which is transparent on an illumination side (top as shown in Fig. 1). It is of approximately rectangular cross-sectional shape, having a larger width than depth. This provides the overall illuminator 1 with a low- profile configuration. There are end caps 15 and 16 secured to the ends of the housing 10, and the end cap 16 has an auxiliary light emitter 17 for emergency use. The illuminator 1 is mounted with brackets 77.

Referring to Fig. 2, the space within the elongate housing 2 is divided into an optical compartment 79 for LEDs and their substrate for light emission, and a power supply compartment 78 for drive circuits and power supply components. The compartments are divided by a plate 70 of aluminium material.

The plate 70 has two pairs of longitudinal grooves 71 retaining PCBs 72 having linear arrays of LEDs 73. The plate 70 is itself supported by a pair of opposed longitudinal grooves 75 forming an integral part of the housing 10. The housing 10 is also formed with a pair of opposed external lips 76 on the side of the drive circuit compartment for supporting the luminaire mounting brackets 77. The brackets 77 can be clipped to any desired longitudinal position, for mounting the luminaire at a desired location.

Fig. 2 also shows cables 85 in the drive circuit compartment 78, beneath the dividing plate 70 as viewed in Fig. 2. It will be appreciated that there is considerable space within this compartment for any of a range of drive circuit and power supply components. Power supply connections to these circuits are via an end cap, as described in more detail below.

The housing 10 material within the field of view of emission of the LEDs 73 integrally forms a diffuser 81 for a 100° beam emitted by the LEDs 73.

In many examples of use, the luminaire 1 is secured to a ceiling by the mounting brackets 77, and hence the power supply compartment 78 is above the LED compartment 79, the field of emission through the diffuser 81 being downward.

Referring to Figs. 3 to 7, the end cap 15 has a gland 26 for IP66 sealing training of power cables into terminals 97 within the end cap 15. The end cap 16 has a similar overall configuration, but does not receive power cables, and includes the auxiliary light emitter 17 for emergency use. The end cap 15 has an end wall 25 with the gland 26. The end wall 25 is an integral part of a housing 28 of the end cap 15.

Each end cap has a hinged cover 27, shown in its open position in Fig. 3. Each cover 27 is hinged by an integral hinge 35 comprising a curved retainer 36 on the end cap housing and which is open-ended, and a bar 37 extending between supports 38 on the cover. The curved retainer 36 extends transversely across the end cap housing 28, and the bar 37 extends transversely across the cover 27. As is clear from Fig. 4, the retainer 36 retains the bar 37 so that it is free to rotate within the retainer, and so the cover 27 is free to rotate. If the luminaire 1 is mounted with the brackets 77 secured to the ceiling, the cover 27 can be opened and allowed to hang down to provide full access by a technician to within the end cap 15 or 16.

A sealing ring or gasket 50(a) on the cover 27 seals the cover 27 against a corresponding rim 50(b) on the end cap housing 28. This, together with an axial sealing ring 55 between the end cap housing 28 and the elongate housing 10 provides IP 66 sealing engagement of the end cap housing 28 to the main housing 10.

As shown in Fig. 3 each end cap cover 27 is retained closed by a screw 84 engaging through a tab 80(a) on the cover 27 and the end wall 25. The tab 80(a) fits into a seat provided by a pair of ridges 80(b) on the housing end wall 25. Also, there are also two pairs of snap fit barbs 83 on the housing and corresponding eyelets 82 on the cover for snap-fitting closing of the lid 27.

Sealing of each end cap is therefore achieved by the cover 27 being sealed comprehensively to the end cap housing 28. The seal comprises the hinge 35, the interfacing seal gasket 50(a) and rim 50(b), the snap-fitting latch or clip fasteners 82/83 at the end opposed to the hinge, and engagement of the tab 80(a) in the seat 80(b) by the screw 84.

It will be appreciated that the end caps can contain any desired auxiliary component, such as a proximity sensor, an emergency light and/or a wireless transceiver. Opposed walls 32 on the cover 27 extend into the volume of the end cap, allowing a component to be gripped and easily inserted and removed.

Fig. 5 shows mounting of an auxiliary light emitter 17. It comprises:

a lens 90 on a base with both internal and external threads,

an LED 91 configured to fit into the lens base,

a threaded tubular support 92,

a gasket 93, and

a nut 94.

The tubular support 92 passes through a hole 95 in the cover 27. The lens 90 incorporates a mounting flange below which there are external threads which engage internal threads of the tubular support 92, which in turn has external threads 96 engaging the nut 94. This allows easy assembly of the emergency LED 91, or indeed any other auxiliary component such as a sensor. The tubular support 92 acts as a support for the whole assembly when it engages the nut 94 and the cover. Also, it acts as a heat sink for heat conduction from the LED 91 or other auxiliary component. Because the lid 27 is removable the auxiliary component can be conveniently assembled away from the luminaire 1. Power can be provided by any suitable power connection within the end cap.

It will be appreciated that the light emitter 17 may be easily installed because of convenience of this mounting assembly and access to both sides of the cover 27 when it is opened. Also, there is excellent resilient sealing to prevent dust and water ingress provided by the seal components 50(a), 50(b) and 55.

Also, there is considerable space within each end cap, to accommodate a number of auxiliary components if desired, and/or to allow convenient connection or disconnection of cable ends to terminals (85/97). This is especially apparent from Fig. 6. This space is readily accessed using a tool to open the cover 27, thereby revealing the full space with access along its full length. Moreover, the cover 27 is retained in place because it is hinged, and it can be easily closed in a manner to re- seal the end cap. These are achieved without need for particular skill or experience by the technician. The versatility is achieved despite the fact that the end cap is sealed, preferably according to IP66 standards.

The hinged cover may be provided with any of a range of components such as an in-built light, a sound emitter, a presence detector electrically linked to a terminal within the end cap. A mounting arrangement such as that of the emergency light emitter 17 may advantageously be used.

The invention is not limited to the embodiments described but may be varied in construction and detail. For example, sealing may be achieved by way of a gasket on the end cap housing instead of or in addition to being on the cover. Fastening of one or both end cap covers may be by way of only a snap-fit or latch fastener without a screw fastener arrangement, or vice versa. The cover hinge may have a groove in the cover instead of in the housing, the bar being on the housing.