GB2305496A

GB2305496A - A lamp

Info

Publication number: GB2305496A
Application number: GB9619731A
Authority: GB
Inventors: David Baxter
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-09-21
Filing date: 1996-09-20
Publication date: 1997-04-09
Anticipated expiration: 2016-09-20
Also published as: GB9619731D0; GB9519335D0; GB2305496B

Abstract

A lamp for decorative effects comprises a fluorescent tube 12 held vertically inside a tubular light shield 29 which has a longitudinally extending aperture 26 whose width is variable by means of a sliding barrier 42. A motor-driven rotating cylindrical filter having different colours spaced around it may be placed between the tube 12 and the shield 29. The lamp may be wall mounted with the aperture towards the wall.

Description

TITLE: A Lamp DESCRIPTION This invention relates to a lamp and, in particular, to a lamp incorporating a fluorescent tube.

The use of fluorescent tubes in lighting units is well known and they have the distinct advantage of being relatively cheap to power compared with the cost of powering a conventional incandescent bulb having the equivalent light output. However, the size of fluorescent tubes has to date largely restricted their use to offices and to utility rooms in domestic households.

An aim of the present invention is to provide a lamp incorporating a fluorescent tube and which can be used in any domestic location.

In accordance with the present invention there is provided a lamp comprising a fluorescent tube, means for holding said fluorescent tube substantially vertically and a shield whereby light from said fluorescent tube is emitted from the lamp in a predefined direction only.

The shield may surround all but a predetermined longitudinal area of the fluorescent tube. The shield may be of any shape but preferably is substantially circular in cross-section. Preferably, the shield is formed by a tube having a longitudinal aperture formed therein and through which light from the fluorescent tube is emitted.

The aperture forms an arc of the circumference of the tube. Said arc may subtend an angle in a range of 60 -180 but preferably in a range of 1000-1500.

A movable shutter may be provided so as to enable the size of the aperture through which the light is transmitted to be varied.

The shield may have an inner surface which is reflective thereby reflecting light emitted from the fluorescent tube towards said aperture.

The shield may be formed of aluminium.

The lamp may be provided with a transparent cover for said aperture.

The lamp may further comprise a coloured filter through which light emitted by the fluorescent tube is transmitted. The filter may be fixed across said aperture. Alternatively, the filter may form a wall or a part thereof of a hollow cylinder which is preferably located inbetween said fluorescent tube and the shield.

It is preferred that said cylinder is rotatable about a vertical axis which may also be the axis of said fluorescent tube. The lamp may further comprise an electric motor for rotating the cylinder with respect to the fluorescent tube and shield.

The wall of said cylinder may be formed by a plurality of different coloured filters. Preferably, the section of the wall formed by each coloured filter forms an arc which subtends an angle which corresponds to the arc subtended by said aperture. In one embodiment of the present invention, when said arc formed by the aperture subtends an angle of XO, there are provided approximately n different coloured filters where n=360/X. Preferably, there are provided three different coloured filters.

In a preferred embodiment of the invention, the lamp further comprises a support base from which said shield may extend substantially vertically.

The lamp may be free standing and is preferably constructed so as to enable it to be moved easily to any desirable location. In use, the lamp may be positioned such that it is adjacent a wall or corner of a room with, preferably, said aperture directly opposing said wall or corner. The lamp may be positioned such that the fluorescent tube is spaced from the wall or corner by a distance of no more that 50cm and, preferably, in the range of 10-30cm. By positioning the lamp in such a manner, the room is illuminated by virtue of emitted light being reflected from the wall or corner.

In an alternative embodiment of the invention, said lamp is supported by one or more wall brackets wherein said wall brackets preferably ensure that the fluorescent tube is held parallel to a wall. In this alternative embodiment, it is preferred that the aperture, through which light from the fluorescent tube is emitted, is positioned directly opposing a wall. In this embodiment, a room in which a lamp is located is illuminated by virtue of the fact that the light emitted by the lamp is reflected from said associated wall.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings wherein: Figure 1 is a front view of a lamp according to an embodiment of the present invention; Figure 2 is a detail of a lamp taken along the lines X-X of figure 1; Figure 3 is a front view of a lamp according to a further embodiment of the present invention; and Figure 4 is a detail of a lamp taken along the lines Y-Y of figure 3; Figure 5 is a front detail of a lower part of a lamp according to yet a further embodiment of the invention; Figure 6 is an enlarged view, taken along lines Z-Z, of the lamp illustrated in figure 5; Figure 7 is a side sectional view of the lamp shown in figures 4 and 5 taken in the direction of lines A-A; and Figure 8 is a front detail of a lower part of a lamp illustrating an alternative arrangement for rotating a filter.

With reference to figures 1 and 2 in the first instance, a lamp is indicated generally by numeral 10.

Lamp 10 comprises a fluorescent tube 12, tubular shield 14, holding means 16 and a base 18.

Holding means 16 comprises a rear support strip 20 which extends the vertical height of the fluorescent tube 12 between a bottom and top base (not shown). The top and bottom bases form the necessary electrical contact with the fluorescent tube and supply electrical power thereto. The manner in which power can be supplied to the fluorescent tube via the top and/or bottom base will be understood by the man skilled in the art and hence further details will not be given here.

An aperture 26 is formed in the tubular shield and extends the vertical height of the fluorescent tube.

Light from said fluorescent tube is emitted from the lamp through said aperture. The lamp further comprises a coloured light filter 28 formed across said aperture.

The arc which the aperture forms subtends an angle of 900.

The shield 14 has an inner surface 29 which is reflective and reflects light incident thereon towards said aperture 26.

In use, the lamp is positioned in a room adjacent a wall or a corner formed by two walls such that aperture 26 is directly opposing the wall or corner.

The distance. of separation between the lamp and wall/corner and the angle of the arc is such that an observer in the room will only view light emitted by the lamp which has been reflected from the wall or corner.

The distance of separation is, ideally, between 10cm and 30cm as measured between the fluorescent tube and the wall or corner.

Referring to figures 3 and 4, a further embodiment of the present invention is illustrated with like numerals denoting like features in figures 1 and 2.

A lamp 40 comprises a movable shutter 42 having a handle 44. The shutter 42 is located on shield 14 and can be moved in the direction indicated by arrows 'A'.

The shutter can be moved so as to narrow or widen aperture 26 and thereby change the light effect of lamp 40. The lamp may be provided with a coloured light filter (not shown) and located across aperture 26.

In use, the lamp is positioned in a room adjacent a wall or a corner formed by two walls such that aperture 26 is directly opposing the wall or corner. As a result, the room is illuminated by the emitted light reflecting off the wall or corner.

Another embodiment of the present invention will now be described with reference to figures 5, 6 and 7.

A lamp 50 comprises a fluorescent tube 52, a tubular shield 54, filter 56, fluorescent tube support means 58, 60 and base 62.

The. fluorescent tube 52 is held vertically between support means 58 and 60 located one at the bottom and one at the top of tubular shield 54. The support means 60 located at the top of the fluorescent tube is secured to the shield 54. The shield 54 has an aperture 64 formed therein and said aperture is defined by an arc which subtends an angle of 120 degrees.

Formed in the shield 54, near the bottom end thereof, are two horizontal slots 65, 66 which extend partly around the shield's circumference.

A filter 56 comprises a cylinder wherein a wall thereof is formed by a red, blue and green filter 68, 70 and 72. Each coloured filter forms a third of the cylinder wall and is defined by an arc which subtends an angle of 120 degrees. The filter. 56 is positioned between the fluorescent tube and shield 54. The filter 56 is rotatable about the fluorescent tube and to ease said rotation it is supported on bearings (not shown).

Provided near the bottom end of the filter 56 are a series of holes 74 which are aligned with slots 65, 66.

The electrical connection between the ends of the fluorescent tube is formed by an electrical cable 76 which passes from support means 58 through base 62, runs the length of a channel 78 formed on the rear of shield 54 and then through shield 54 to support means 60.

The lamp 50 is used in a similar manner as described in the above embodiments although the filter 56 can be rotated about. the fluorescent tube to the desired colour of filter. The filter is rotated by inserting a peg through one of the slots and into the hole of the filter. The peg is then moved within the slot thereby rotating the filter. The filter is rotated into a position such that a single colour filter is aligned with aperture 64.

It is envisaged that the wall of the cylinder forming filter 56 may comprise more than three different coloured filters. Furthermore, the section of the wall aligned with aperture 64 ie the part of the cylindrical filter through which light emitted from the lamp passes, may be formed by a plurality of different coloured filters.

An alternative arrangement for rotating filter 56 is illustrated in figure 8 wherein like numerals represent like items. Aperture 64, formed in shield 54, is defined by an arc which subtends an angle which is slightly less than 120 degrees ; 116 degrees. The shield 54 has two opposing side edges 80, 82 each having a recess 84, 85 respectively. Said recesses are formed in the side edges at a position located at the bottom of aperture 64. Formed in filter 56 are three holes 86 which are located one at the junction of each of the three coloured filters 68, 70 and 72 and at a position so as to be alignable with recesses 84, 85.

The filter is mounted on bearings, in a similar manner as in the arrangement,described with reference to figure 5, so as to ease its rotation about fluorescent tube 52.

In order to change the colour of the filter through which light is emitted it is necessary to rotate filter 56 about fluorescent tube 52. This is simply achieved by inserting a peg into the hole in the filter which is aligned with recess 85 and moving the peg in a direction towards recess 84. Once the peg is located in recess 84, filter 56 will have been rotated to such an extent that the next coloured filter will cover aperture 56. In this manner, filter 56 can be rotated so to position the desired colour of filter.

In yet a further embodiment of the invention (not illustrated), filter 56 is rotated by an electric motor.

The motor may be operated such that the filter is rotated slowly and continually. Hence, if the filter comprises three different colour filters then for most of the operation of the motor, the lamp will emit two different colours of light.

It is envisaged that a lamp described in any one of the above described embodiments could be secured in position relative to a wall by one or more brackets.

The lamp would be positioned such that the aperture formed in the shield is located directly opposing said wall.

Claims

1. A lamp comprising a fluorescent tube, means for holding said fluorescent tube substantially vertically and a shield whereby light from said fluorescent tube is emitted from the lamp in a predefined direction only.

2. A lamp as claimed in claim 1 wherein said shield is formed by a tube having a longitudinal aperture formed therein and through which light from the fluorescent tube is emitted.

3. A lamp as claimed in claim 2 wherein said aperture forms an arc of the circumference of the tube and said arc subtends an angle in a range of 60 -180 .

4. A lamp as claimed in claim 2 or 3 wherein said lamp further comprises a movable shutter so as to enable the size of the aperture through which the light is transmitted to be varied.

5. A lamp as claimed in claim 2, 3 or 4 wherein said shield has an inner surface which is reflective thereby reflecting light emitted from the fluorescent tube towards said aperture.

6. A lamp as claimed in any one of claims 1 to 5 wherein the lamp further comprises a coloured filter through which light emitted by the fluorescent tube is transmitted.

7. A lamp as claimed in claim 6 wherein the filter forms a wall or a part thereof of a hollow cylinder located around said fluorescent tube and in between said tube and the shield.

8. A lamp as claimed in claim 7 wherein the wall of said cylinder is formed of a plurality of different coloured filters.

9. A lamp as claimed in claim 8 wherein a section of the wall formed by each coloured filter forms an arc which subtends an angle which corresponds to the arc subtended by said aperture.

10. A lamp as claimed in claim 7, 8 or 9 wherein said hollow cylinder is rotatable about a vertical axis.

11. A lamp as claimed in claim 10 wherein said hollow cylinder is rotated under the control of an electric motor.

12. A lamp as claimed in any one of claims 1 to 11 wherein, in use, said lamp is wall mounted.

13. A lamp as claimed in any one of claims 2 to 11 wherein, in use, said lamp is positioned adjacent a wall such that said aperture is directly opposing said wall.

14. A lamp substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.