GB2452747A

GB2452747A - Lamp holder with internal obstruction

Info

Publication number: GB2452747A
Application number: GB0717879A
Authority: GB
Inventors: Peter Staniforth
Original assignee: NVC
Current assignee: NVC
Priority date: 2007-09-13
Filing date: 2007-09-13
Publication date: 2009-03-18
Also published as: GB0717879D0

Abstract

A collar 1 of a lamp holder has a pair of diametrically opposed protrusions (8, Fig 3) projecting from its internal circumference. These projections enable the holder only to be connected to electric lamps 3 whose terminal caps 2 include open ended channels 14 which complement the sizes and positions of the diametrically opposed protrusions. This can be used to ensure that the lamp holder is only used with energy efficient light bulbs. The lamp holder may have a bayonet fitting.

Description

Electric lamp holders and lamps therefore This invention relates to lamp holders for electric lamps. The invention also relates to a lamp holder in combination with a lamp, and to electric lamps per Se.

Energy efficient electric lamps are available but are not used as widely as they should be to mcet the need to conserve energy wherever possible. One object of this invention is to provide lamp holders to which only a limited range of electric lamps, eg energy efficient lamps, can be attached thereby extending the use of energy efficient lamps. The invention further sets out to provide electric lamps modified to enable them to be accepted by lamp holders in accordance with the invention.

In one aspect the invention provides a lamp holder having a collar from the internal circumference of which protrudes at least one abutment surface.

Preferably, two diametrically opposed abutment surfaces are provided.

The or each abutment surface may comprise indentations pressed or otherwise formed in the internal circumference of the collar. The or each abutment surface is preferably generally circular in cross section. Other cross sections can, however, be used.

In another aspect, the invention provides, in combination, a lamp holder connectable at one end to a source of electric current and including at its other end a collar into which the terminal cap of an electric lamp can be received, the collar including at least one inwardly projecting abutment surface positioned and dimensioned to move within an open ended channel formed in the terminal cap of a lamp to permit connection of the lamp to the holder.

Preferably, two diametrically opposed abutment surfaces are formed in the collar circumference each of which is positioned and dimensioned to be received within an open ended channel formed in the terminal cap of the lamp.

The width of the or each channel is preferably at least twice that of the or each abutment surface to facilitate a bayonet fitting of the lamp to the lamp holder.

Preferably, the lamp is an energy efficient lamp.

In a further aspect, the invention provides an electric lamp having a terminal cap secured to an evacuated bulb housing a light emitting element, the cap including at least one lengthwise extending open-ended channel formed in its surface remote from the bulb.

The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side view of a lamp holder in accordance with this invention; Figure 2 is a section taken along line II-!! of Figure 1; Figure 3 is a plan view from above of the lamp holder shown in Figures 1 and 2; Figure 4 is a side view of the end cap of an electric lamp in accordance with the invention; Figure 5 is a section taken along line V-V of Figure 4; Figure 6 is a plan view from below of the lamp shown in Figures 4 and 5; and Figure 7 shows an energy efficient lamp and lamp holder in accordance with the invention.

The lamp holder shown in Figures 1 to 3 and 7 comprises an open-ended collar 1 for receiving, in use, the end cap 2 (see Figure 7) of an electric lamp 3. The collar I is secured to a base 4 having a terminal block 5 connectable by wiring (not shown) to a source of electric current. Formed in the opposite sides of the collar 1 are two open-ended arcuate slots 6 which cooperate with pins 7 protruding from the perimeter of the end cap 2 to define a conventional bayonet fitting.

Protruding inwardly from the internal surface of the collar 1 are two diametrically opposed projections 8.

Turning now to Figures 4 to 6 and 7, the illustrated electric lamp 3 is an energy efficient lamp which comprises a sealed evacuated bulb 10 housing a light emitting S tube II connected to terminals 12 carried by the end cap 2. Formed in the perimeter of the end cap 2 are diametrically opposed open-ended channels 14. These channels are dimensioned and positioned to receive the projections 8 of the lamp holder when the lamp is being connected to the lamp holder. The width of each channel is sufficient to enable the bayonet connection between the lamp and the lamp holder to be effected.

In use, provided the channels 14 are aligned with the projections 8 the lamp can be connected to the holder in the conventional way. However, a lamp not having the channels will be prevented from forming a connection with the holder by the projections 8 protruding inwardly from the surface of the collar 1. Thus, extensive use of lamp holders in accordance with the invention can provide a useful incentive to a greater use of energy efficient electric lamps simply by ensuring that such lamps are substantially as described above.

It will be appreciated that the foregoing is simply exemplary of electric lamp holders and lamps in accordance with the invention and that modifications can readily be made to these lamp holders and lamps without departing from the true scope of the invention.

Claims

Claims I A lamp holder for connection to a lamp comprises a collar which is open at one end and includes a pair of open ended channels for receiving pins protruding outwardly from the external surface of the terminal cap of a lamp to define a bayonet fitting, the collar including at least one abutment surface protruding from its internal circumference.
2 A lamp holder as claimed in Claim 1 wherein the collar includes two diametrically opposed abutment surfaces protruding from its internal surface.
3 A lamp holder as claimed in Claim 1 or Claim 2 wherein the or each abutment surface comprises an indentation formed in the circumference of the collar.
4 A lamp holder as claimed in any one of the preceding Claims wherein the or each abutment surface is generally circular in plan view.
In combination a lamp holder connectable at one end to a source of electric current and including at its other end a collar into which the terminal cap of an electric lamp can be received, the collar including at least one inwardly projecting abutment surface positioned and dimensioned to move within an open ended channel formed in the terminal end of the lamp to permit connection of the lamp to the lamp holder.
6 A combination as claimed in Claim 5 wherein two diametrically opposed abutment surfaces are formed in the collar circumference each of which is positioned and dimensioned to be received within a complementary open ended channel formed in the terminal cap of the lamp.
7 A combination as claimed in Claim 5 or Claim 6 wherein the width of the or each channel is at least twice that of the or each abutment surface.
8 A combination as claimed in Claim 7 wherein the channel width is approximately three times that abutment surface.
9 A lamp holder having a collar from the internal circumference of which protrudes at least one abutment surface.
An electric lamp having a terminal cap secured to an evacuated bulb housing a light emitting element, the cap including at least one lengthwise extending channel formed in its surface remove from the bulb.
11 A lamp holder substantially as herein disclosed and as illustrated in Figures 1 to 3 of the accompanying drawings.
12 A lamp substantially as herein disclosed and as illustrated in Figures 4 to 6 of the accompanying drawings.