GB2194625A

GB2194625A - Lamp unit

Info

Publication number: GB2194625A
Application number: GB08620318A
Authority: GB
Inventors: Ian Jack Pickering; Henry Charles Horton
Original assignee: Crabtree Electrical Industries Ltd
Current assignee: Crabtree Electrical Industries Ltd
Priority date: 1986-08-21
Filing date: 1986-08-21
Publication date: 1988-03-09
Anticipated expiration: 2006-08-21
Also published as: FR2603091A1; GB2194625B; FR2603091B1; GB8620318D0; IE872137L; ZA875922B; IE60367B1

Abstract

A lamp unit comprises a housing (6) of generally conventional construction, located within which is an electric circuit. Located at spaced intervals within the housing are a pair of primary contacts or terminals, adjacent to each of which in an upper surface of the housing a small aperture (12) is provided. The unit comprises a diffusing cover (14) comprising at each inner end region a socket assembly, the socket assemblies providing means by which an incandescent lamp (18) may be mounted on the cover (14) in electrical contact with auxiliary terminals. A sub-unit comprising lamp (18) and cover (14) may be removed from the housing, for example for replacement of the lamp (18), and re-assembled with the housing into a position in which each auxiliary contact is in electrical connection with one of the primary contacts. <IMAGE>

Description

SPECIFICATION Improvements relating to lamp units This invention is concerned with improvements relating to lamp units, particularly of the kind (hereinafter referred to as being of the kind specified) comprising a housing, an elongate lamp adapted to be located in the housing in electrical contact with terminals of the housing, and a diffusing cover adapted to be mounted over the lamp.

Coventionally the housing is adapted to be secured to a wall or other flat surface, and the lamp may be fluorescent or incandescent.

With increasing safety requirements it is desirable for such units to be electrically safe, and in particular it is not possible to touch any live terminals especially in units (usually incandescent) of the type found commonly in bathrooms.

According to this invention there is provided a lamp unit of the kind specified wherein the diffusing cover comprises a mounting for the lamp, and auxiliary terminals with which a lamp when mounted on the cover is in electrical contact, the cover being mountable on the housing with the auxiliary terminals in electrical contact with the terminals (hereinafter referred to as the primary terminals) of the housing.

In this manner when the lamp needs replacing, the cover and lamp may be removed from the housing as a sub-unit, with the lamp remaining in electrical contact with the auxiliary terminals.

Since the primary terminals need not be such as to enable them to be engaged by the lamp, they may be shielded relatively easily to prevent touching when the cover and lamp are removed.

Thus preferably the housing comprises an aperture adjacent to each primary terminal, each aperture being of a size sufficient to prevent the insertion of a finger, but being sufficiently large to permit passage therethrough of part one of the auxiliary terminals.

Preferably the cover comprises at each end region a shield which provides a recess into which recess an end portion of the lamp may be inserted into engagement with the auxiliary terminals. Preferably the shields each cooperate with the housing when the cover is engaged with the housing, the housing partially covering the recess to provide an aperture through which the end portion of the lamp extends. Thus preferably the aperture defined by the shield and housing is sufficient in size to accommodate the end portion of the lamp with sufficient clearance to permit passage therethrough of a finger.

Preferably the cover comprises a shutter which is urged normally into an operative position in which, in the absence of a lamp on the cover, prevents finger contact with the primary terminals when the cover is mounted on the housing.

Thus advantageously each shutter is mounted adjacent to a shield, and in the absence of a lamp, the shutter extends across the aperture defined by the shield and the housing - i.e. adopts at least in part the position which otherwise would be adopted by the lamp when present.

Thus when the cover alone is mounted on the housing, the shutter restricts access to the auxiliary terminals.

According to this invention there is also provided a lamp unit of the kind specified comprising: (a) a housing; (b) primary terminals located within the housing at spaced regions; (c) an aperture in the housing adjacent to each primary terminal; (d) a diffusing cover member comprising formations engagable with the housing to enable the cover member to be mounted on the housing; and (e) two sockets assemblies in the cover member, each socket assembly comprising an auxiliary terminal and the two socket assemblies providing means by which an elongate lamp may be mounted on the cover.

Thus the cover member and lamp provide a sub-unit which may be engaged with the housing with the auxiliary terminals in electrical connection with the primary terminals.

There will now be given a detailed description, to be read with reference to the accompanying drawings, of a lamp unit is the preferred embodiment of this invention, having been selected for the purposes of illustrating the invention by way of example, and a modified construction thereof, In the accompanying drawings:: Figure 1 is a schematic perspective view of the preferred embodiment, showing a sub-unit separated from a housing thereof; Figure 2 is a schematic view of an electrical circuit of the lamp unit; Figure 3 is a schematic sectional view showing the sub-unit separated from the housing; Figure 4 is a view corresponding to Fig. 3 showing the sub-unit in operative engagement with the housing; Figure 5 is a view of part of the modified construction, corresponding to Fig. 4 but with a lamp of the unit removed; Figure 6 is a end elevation, view in the direction of the Arrow A of Fig. 5; Figure 7 is a view corresponding to Fig. 3 of the modified construction; and Figure 8 is a view corresponding to Fig. 4 of the modified construction.

The lamp unit which is the preferred embodiment of this invention comprises a housing 6 generally of conventional construction, located within which is an electric circuit (see Fig. 2) comprising a power circuit adapted to power a shaver socket outlet 8, through a voltage-selector switch 9, and a lighting circuit under the control of a pull-cord 5. The outlet 8 is switched on and off automatically on insertion and withdrawal respectively of a shaver plug.

Located at spaced intervals within the housing are a pair of primary contacts or terminals 10, adjacent to each of which in an upper surface of the housing a small aperture 12 is provided.

The unit comprises a diffusing cover 14 comprising at each inner end region socket assembly 16, the socket assemblies providing means by which an incandescent lamp 18 may be mounted on the cover 14 in electrical contact with auxiliary contacts or terminals 20. Extending above and partially round each auxiliary contact 20 is a shield 22, the shield providing an upwardly-open recess, as viewed in Fig. 3, into which the end portions 19 of the lamp may be located.

The Auxiliary contacts 20 are so constructed as to provide a concave seating for the lamp contact, and comprises a downwardly-extending stem 21.

The housing 6 is provided with a channel 7 on each side, into which a lip 15 of the cover may be slotted to secure the cover to the housing in a desired location, in which the stem 21 ofthe auxiliary terminals protrude through the apertures 12 of the housing in an electrical engagement with the primary contacts, (see Fig. 4).

In this manner when the cover 14 is removed from the housing, it will carry with it the lamp 18 as a sub-unit, the stem 21 of each auxiliary contact sliding from engagement with one of the two primary contacts, and by virtue of the small size of the aperture 12, possibilty of live terminals being touched inadvertently is eliminated, (see Fig. 3).

In the modified construction shown in Figs.

5 to 8, a shutter 26 is pivotally mounted in the recess provided by each shield 22, each shutter 26 being urged into an operative position shown in Fig. 5, by a spring 28. In said operative position the shutter, when the cover along is mounted on the housing extends across the aperture defined jointly by the shield and the housing, within which aperture the end region 19 of the lamp would normally extend, when in position, thus restricting access to the auxiliary terminals when the lamp is not in position, (see Fig. 5).

With the cover removed from the housing, on the upward insertion of the lamp into engagement with the two sockets 22, the end regions 19 of the lamp each engage a respective one of the two shutters 26 to move the shutter into an inoperative position (shown in Fig. 7), permitting subsequent reassembly of the sub-unit comprising the cover and lamp into engagement with the housing, as can be seen in Fig. 8.

The features disclosed in the foregoing description, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, or a class or group of substances or compositions, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A lamp unit of the kind specified wherein the defusing cover comprises a mounting for the lamp, and auxiliary terminals with which a lamp when mounted on the cover is in electrical contact, and the cover being mountable on the housing with the auxiliary terminals in electrical contact with the terminals of the housing.

2. A lamp unit according to Claim 1 wherein the terminals of the housing are shielded to prevent touching when the cover and lamp are removed from the housing.

3. A lamp unit according to Claim 2 wherein the housing comprises an aperture adjacent to each terminal, each aperature being of a size to prevent the insertion of a finger, but being sufficiently large to prevent passage therethrough of part of one of the auxiliary terminals.

4. A lamp unit according to any one of the preceding claims wherein the cover comprises at each end region a shield which provides a recess into which an end portion of the lamp may be inserted into engagement with the auxiliary terminals.

5. A lamp unit according to Claim 4 wherein the shields each co-operate with the housing when the cover is engaged with the housing, the housing partially covering the recess to provide an aperture to which an end portion of the lamp extends.

6. A lamp unit according to Claim 5 wherein the aperture defined by the shield and housing is sufficient in size to accomodate an end portion of the lamp with insufficient clearance to permit passage therethrough of a finger.

7. A lamp unit according to any one of the preceding claims wherein the cover comprises a shutter which is normally urged into an operative position in which, in the absence of a lamp on the cover, the shutter prevents finger contact with the terminals of the housing when the cover is mounted on the housing.

8. A lamp unit according to Claim 7 wherein each shutter is mounted adjacent to a shield, and in the absence of a lamp the shutter extends across the aperture defined by the shield and the housing.

9. A lamp unit of the kind specified com prjsing: (a) a housing; (b) primary terminals located within the housing at spaced regions; (c) an aperture in the housing adjacent to each primary terminal; (d) a defusing cover member comprising formations engagable with the housing to enable the cover member to be mounted on the housing, and (e) two sockets assemblies in the cover member, each socket assembly comprising an auxiliary terminal and the two socket assemblies providing means by which an elongate lamp may be mounted on the cover.

10. A lamp unit according to Claim 9 wherein the cover member and lamp provide a sub-unit which may be engaged with the housing with the auxiliary terminals in electrical connection with the primary terminals.

11. A lamp unit constructed and arranged substantially as hereinbefore described with reference to the accompanying drawings.

12. Any novel feature or novel combination of features disclosed herein and/or shown in the accompanying drawings.