GB2064089A - Improvements in or relating to lighting apparatus - Google Patents

Abstract

Lighting apparatus comprises a lamp assembly having a housing (10) for supporting a lamp (12), the housing having a pair of electrical sockets (14) formed in end plates (11) of the housing. The socket spigots are accessible from outside the housing and wiring means is provided for conducting electrical power from the sockets to the lamp (12). Connectors comprising a pair of connected plug means (20) each capable of being inserted in a socket (14) are provided for electrically connecting together adjacent lamp assemblies in use. <IMAGE>

Description

SPECIFICATION Improvements in or relating to lighting apparatus The invention relates to lighting apparatus, and more particularly but not exclusively to luminaires the type comprising an elongate housing and a tubular lamp supported by the housing.

In, for example, shop fittings where many luminaires of the type hereinbefore mentioned are required in order to light a large area, it has in the past been necessary for each luminaire to be connected individually to the power supply. Each such an operation involves at least some dismantling of the luminaire to afford access to the interior of the housing so that a wire from the power supply of the building can be connected to the luminaire. Such a lighting installation has therefore in the past been time consuming and also labour intensive to install.

According to the invention there is provided lighting apparatus comprising a lamp assembly having a housing for supporting lamp means, the housing having at least one electrical socket means accessible from outside the housing and wiring means for conducting electrical power from the or each socket means to the lamp means, and connector means comprising pair of plugs means and a flexible cable connecting the plug means, each plug means being capable of being inserted in a socket means for electrically connecting together adjacent lamp assemblies in use.

The lamp assembly may comprise an elongate housing for supporting an elongate lamp, and may comprise a pair of end plates mounted on the housing, which end plates support a lamp in use.

One socket means is preferably formed in each end plate, and each end plate may be in the form of a one-piece moulding.

The apparatus preferably comprises means for permitting insertion of a plug means into a socket means in one relative orientation only. Said orientation defining means may comprise an elongate rib on one or other of each socket means and an elongate groove engageable by the rib on the other of the plug means and socket means.

The groove may be formed on each plug means.

The plug means and socket means may be substantially cylindrical.

The or each socket means may comprise a cylindrical recess and three tubular spigots extending from the base thereof inside the recess, an electrically connected socket being located within each tubular spigot.

The plug means may comprise a cylindrical engagement portion for engaging the cylindrical recess in the socket means, three cylindrical recesses for engagement by the spigots of the socket means and an electrically connected pin located in each cylindrical recess for engagement with an electrically connected socket of the socket means.

The socket means may comprise a first moulding of plastics material providing said recess and spigots, and a second moulding of plastics material carrying said electrically connected sockets.

The plug means may comprise a cylindrical outer body portion, a cylindrical inner body portion carrying the electrically connected pins and means for holding together the inner and outer body portions.

The inner body portion may be formed in two parts.

The invention further provides lighting apparatus according to the invention comprising a plurality of lamp assemblies connected together electrically by one of the connector means between the or each pair of lamp assemblies.

By way of example, two embodiments of lighting apparatus according to the invention wili now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a series of lamp assemblies connected by connectors; Figure 2 is a front view of an end plate of a lamp assembly; Figure 3 is a rear view of the end plate of Figure 2; Figure 4 is a view of one end of a plug; Figure 5 is a view of the other end of the plug of Figure 4; Figure 6 is a sectional view along the lines VI--VI of both Figures 3 and 4 to indicate how a plug is inserted in a socket; and Figure 7 is a sectional side view, partly exploded, of a second embodiments of an end plate having a socket therein and a plug.

As shown in Figure 1, a lamp assembly comprises a housing 10 on which are mounted end plates 1. An elongate lamp 12 of conventional design is supported by the end plates 11 and the ends of the lamp 12 make electrical contact with contact elements 13 mounted one on each end plate 1 The contact elements 13 are conventional in design.

Each end plate 11 is a one piece moulding, conveniently of plastics material and preferably apolycarbonate material. Each end plate 11 is formed with a socket 14 which is substantially cylindrical in cross-section and has three tubular spigots 1 5 extending from the base 1 6 of the socket to the front face 1 7 of the end plate 11.

The rear face of the end plate 11 (Figure 3) is provided with projections for engaging parts of the housing 10 to maintain the end plate in position relative to the housing 10. In addition, the socket 14 is provided with an alignment rib 18 extending perpendicular to the front face 1 7 of the end plate 11.

Female contact elements 1 9 are inserted one in to each of the tubular spigots 1 5 of each end plate 11 and electrical connections are made between corresponding female contact elements 1 9 in each end plate and from appropriate female contact elements 1 9 to the contact plates 13 to carry electrical power to the lamp 12. The connections between the sockets 14 and the contact plates 13 are made during assembly of the housing 10.

In order to make an electrical connection between adjacent lamp assemblies, connector elements comprising a pair of plugs 20 connected by a three core wire 21 are provided. Each plug 20 is substantially cylindrical in cross-section and is formed with three tubular recesses 22, each dimensioned to be engageable by a tubular spigot 1 5 of the socket means. Male contact elements 23 are inserted into a forward block portion 24 of each plug 20 in such a way that a pin 25 lies centrally in the tubular recess 22. Thus when a plug member 20 is inserted into a socket 14 the pins 25 engage the female contact elements 19 to make electrical connections therebetween.

Electrical connection is made between corresponding male contact elements 23 by the three core cable 21. The three core cable 21 passes through a plastics ring 26 which, when jammed in the end of rear plug portion 27 grips the cable 21 to prevent pulling of the wire of the cable 21 from the male contact elements 23. As shown in Figure 4, each plug 20 is provided with an elongate groove 28 which is engageable in use by an elongate rib 18 to ensure that the plug 20 can be engaged in the associated socket 14 in one orientation only. This prevents incorrect electrical connection between the plug and the socket.

A second embodiment of a plug and socket arrangement is shown in Figure 7. An end plate 30 is moulded from plastics material and adapted to be secured to the housing 10 (Figure 1). The external appearance of the end plate 30 is identical to that of the end plate 11, and has a socket 31 consisting of cylindrical recess from the base of which extend three tubular spigots 32.

However, whereas the end plate 11 of the first embodiment is a one piece moulding, in the second embodiment a socket holding member 33 is formed as a separate moulding. The socket holding member 33 has three tapered passages 34 through it, and an electrically connected socket 35 is engaged in each passage 34. The holding member 33 has a pair of annular ribs 36 on the cylindrical surface thereof, and these ribs 36 engage an annular rib 37 on a receiving portion 38 of the end plate 30.

Whereas the plug 20 of the first embodiment is a two piece moulding, the second embodiment provides a plug formed in three parts, with a further part for gripping the cable. The plug consists of cover moulding 39 of plastics material, a cable grip 40, a body 41 and a pin locator moulding 42 locating electrically connected pins 43.

The cover moulding 39 has a frustoconical inner end surface 44 against which seats frustoconical surface 45 of the cable grip 40. The frustoconical portion of the cable grip is in the form of a split ring, and legs 46 are pushed during assembly of the plug, by the body and pin locator mouldings to force the cable grip against the surface 44 of cover moulding and thereby clamp the cable grip around the cable.

The pin locator moulding 42 has three passages through which the electrically connected pins 43 pass, and aligned passages are provided in the body moulding 41. Cylindrical recesses 46 in the end of the body moulding are engaged by tubular spigots 32 of the socket 31.

The body moulding 41 has an annular rib 47 which engages on annular recess 48 in the cover moulding 39 to lock the plug parts together.

To ensure that the plug may be inserted in one orientation only in the socket 31, an axially extending rib 49 is provided on the socket, and an axially extending groove 40 is formed in the body 41 of the plug.

In use, the lighting apparatus is assembled and the electrical connections made as follows. An electrical power source from the building must be wired into one of the lamp assemblies and when this has been done, further lamp assemblies can be fixed in position adjacent one another and electrical connections made between adjacent lamp assemblies simply by inserting one plug member of a connector element into a socket of one lamp assembly and the other plug member of the connector element into a socket of the adjacent lamp assembly. This offers a significant advantage over lighting apparatus which has hitherto been used since it is no longer necessary to wire in each individual lamp assembly directly from the building; one lamp assembly only needs to be connected to the building and the remaining lamp assemblies can be provided with electrical power through the connector elements connected to the sockets.

Claims (14)

1. Lighting apparatus comprising a lamp assembly having a housing for supporting lamp means. the housing having at least one electrical socket means accessible from outside the housing and wiring means for conducting electrical power from the or each socket means to the lamp means, and connector means comprising pair of plug means and a flexible cable connecting the plug means, each plug means being capable of being inserted in a socket means for electrically connecting together adjacent lamp assemblies in use.

2. Lighting apparatus as claimed in Claim 1 comprising means for permitting insertion of a plug means into a socket means in one relative orientation only.

3. Lighting apparatus as claimed in Claim 2 wherein said orientation defining means comprises an eiongate rib on one or other of each socket means and an elongate groove on the other of the plug means and socket means engageable by the rib.

4. Lighting apparatus as claimed in Claim 3 wherein the groove is formed on each plug means.

5. Lighting apparatus as claimed in any preceding claim wherein the plug means and socket means are substantially cylindrical.

6. Lighting apparatus as claimed in Claim 5 claim wherein the or each socket means comprise a cylindrical recess and three tubular spigots extending from the base thereof inside the recess, on electrically connected socket being located within each tubular spigot.

7. Lighting apparatus as claimed in Claim 6 wherein the plug means comprises a cylindrical engagement portion for engaging the cylindrical recess in the socket means, three cylindrical recesses for engagement by the spigots of the socket means and an electrically connected pin located in each cylindrical recess for engagement with an electrically connected socket of the socket means.

8. Lighting apparatus as claimed in Claim 6 or Claim 7 wherein the socket means comprises a first moulding of plastics material providing said recess and spigots, and a second moulding of plastics material carrying said electrically connected sockets.

9. Lighting apparatus as claimed in Claim 6 or, Claim 7 wherein the socket means comprises a one piece moulding of plastics material.

10. Lighting apparatus as claimed in any one of Claims 6 to 9 wherein the plug means comprises a cylindrical outer body portion, a cylindrical inner body portion carrying the electrically connected pins and means for holding together the inner and outer body portions.

11. Lighting apparatus as claimed in Claim 10 wherein the inner body portion is formed in two parts.

12.Lighting apparatus as claimed in any preceding claim wherein lamp assembly comprises an elongate housing for supporting an elongate lamp.

13. Lighting apparatus as claimed in Claim 12 wherein the housing comprises a pair of end plates for supporting the elongate lamp.

14. Lighting apparatus as claimed in any preceding claim wherein each end plate has a socket means.

1 5. Lighting apparatus as claimed in any preceding claim comprising a plurality of the lamp assemblies connected together electrically by one of the connector means between the or each pair of lamp assemblies.

1 6. Lighting apparatus substantially as hereinbefore described with reference to and shown in Figures 1 to 6 or in Figures 1 and 7 of the accompanying drawings.