IE60367B1

IE60367B1 - Improvements relating to lamp units

Info

Publication number: IE60367B1
Application number: IE213787A
Authority: IE
Original assignee: Crabtree Electrical Ind Ltd
Priority date: 1986-08-21
Filing date: 1987-08-10
Publication date: 1994-07-13
Also published as: IE872137L; GB2194625A; FR2603091A1; FR2603091B1; GB8620318D0; ZA875922B; GB2194625B

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.

Description

This invention is concerned with improvements relating to lamp units, particularly of the kind (hereinafter referred to as being of the kind specified) comprising o 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.

Covent iona I ly 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 reguirements it is desirabie for such units to be electrically safe* and in particular it is not passible 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 comprising: (a) a housing comprising a pair of primary contacts spaced apart in a longitudinal direction of the housing, each being accessible through an aperture in a surface of the housing; (b) a cover assembly comprising a diffusing cover member and spaced socket assemblies providing o mounting for on elongate lamp, wherein the cover assembly is provided with spaced auxiliary contacts, and the cover assembly with the lamp is adapted to be mounted on the housing ( by movement of the cover assembly towards the housing in a direction at right angles to said longitudinal axis whereby the auxiliary contacts pass through the apertures into engagement with respective primary contacts.

In this manner when the lamp needs replacing, the cover and lamp may , be removed from the housing as o 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 each aperture is of a size sufficient to prevent the insertion of a finger, but being sufficiently large to permit passage therethrough of part of one of the auxiliary terminals.

Preferably each socket assembly comprises a shield which provides a 5 recess into which recess an end portion of the lamp may be inserted into engagement with the auxiliary terminals. Preferably each shield cooperates with the housing when the cover assembly is engaged with the housing, the housing partially covering the recess to provide an aperture into 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 insufficient clearance to permit passage therethrough of a finger.

Preferobly each socket assembly comprises a shutter which is urged normally into an operative position in which, in the absence of a lamp on the cover, the shutter prevents finger contoct with the auxiliary terminal when the cover is mounted on the housing.

Thus advantageously each shutter is mounted odjacent to o 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 occess to the auxiliary 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: - 4 FIGURE I 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 Figure 3 showing the sub-unit in operative engagement with the housing; FIGURE 5 is o view of part of the modified construction, corresponding to Figure 4 but with a lamp of the unit removed; FIGURE 6 is o end elevation, view in the direction of the Arrow A of Figure 5; FIGURE 7 te a view corresponding to Figure 3 of the modified construction; and FIGURE 8 is a view corresponding to Figure 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 Figure 2) comprising o power circuit adapted to power o shaver socket outlet 8, through o 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 on upper surface of the housing o small aperture 12 te provided.

The unit comprises o diffusing cover 14 comprising at each inner end region o socket assembly 16, the socket assemblies providing means by which on 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 te a shield 22, the shield providing an upwardly-open recess, os viewed in Figure 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 contoct, and comprises a downwardly-extending stem 21.

The housing 6 te provided with a channel 7 on eoch side, into which o lip 15 of the cover may be slotted to secure the cover to fhe housing in a desired location, in which the stem 21 of the auxiliary terminals protrude through the apertures 12 of the housing in electrical engagement with the primary contacts, (see Figure 4k In this manner when the cover 14 is removed from the housing, it will λ 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 J of the small size of the aperture 12, possibilty of live terminals being touched inadvertently is eliminated, (see Figure 3).

In the modified construction shown in Figures 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 Figure 5, by a spring 28. In said operative position the shutter, when the cover alone 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 Figure 5).

With the cover removed from the housing, on the upward insertion of fbe 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 Figure 7), permitting subsequent reassembly of the sub-unit comprising the cover and lamp into engagement with the housing, as can be seen in Figure 8, involving movement of the cover assembly towards the housing in a direction ot right angles to the longitudinal axis of the lamp 18.

Claims

CLAIMS: V

1. A lamp unit comprising: (a) a housing comprising o pair of primary contacts spaced apart in. a longitudinal direction of the housing, each being accessible through on

2. A lamp unit according to Claim I wherein each aperture is of a size to 15 prevent the insertion of a finger, but is sufficiently large to permit passage therethrough of part of one of the auxiliary terminals.

3. A lamp unit according to one of Claims I and 2 wherein each socket assembly comprises a shield which provides a recess into which on end portion of the lamp may be inserted into engagement with the auxiliary terminals. 20 “4. A lamp unit according to Claim 3 wherein each shield co-operates with the housing when the cover assembly is engaged with the housing, the housing partially covering the recess to provide an aperture into which an end portion of the lamp extends. * σ

4. Sheets Sheet 4 CRABTREE ELECTRICAL INDUSTRIES LIMITED -: j.G V. R. Kelly & Ce. 4 Sheets <·:·' :iNA ,14 F. SL Kelly & O 4 Sheets Sheet 2 CRABTREE ELECTRICAL INDUSTRIES LIMITED P. & Kelly & Co. CRABTREE ELECTRICAL INDUSTRIES LIMITED 4 Sheets Sheet 1 CRABTREE ELECTRICAL INDUSTRIES LIMITED FIG 1 5. Assembly is mounted on the housing.

5. A lamp unit according to Claim 4 wherein the aperture defined by the 25 shield and housing Is sufficient in size to accomodate an end portion of the lamp with insufficient clearance to permit passage therethrough of o finger. 5 aperture in a surface of the housing; (b) a cover assembly comprising a diffusing cover member and spaced socket assemblies providing a mounting for an elongate lamp, wherein the cover assembly is provided with spaced auxiliary contacts, and the cover assembly with the lamp is adapted to be mounted on the housing 10 by movement of the cover assembly towards the housing in a direction at right angles to said longitudinal axis whereby the auxiliary contacts pass through the apertures into engagement with respective primary contacts.

6. A lamp unit according to any one of the preceding claims wherein each socket assembly comprises o 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 auxiliary terminal when the cover

7. A lamp unit according to Claim 6 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.

8. A lamp unit according to Claim . 1 constructed and arranged 10 substantially as hereinbefore described with reference to the accompanying drawings.