GB2184649A - Lighting device for lighting writing tables or similar work tables - Google Patents

Abstract

In a lighting device an end portion of a light fitting (1) of the lighting device is secured to a column (2) which is arranged upon the writing table (4) at the side of the working surface (15) thereof, the light fitting (1) being so designed that the light emitting parts (10) with fluorescent tube (11) and reflector (12) are located substantially above an edge (13) of a writing table, and the reflector (12) is asymmetrically designed and provided to throw light towards the working surface (15) located in front of said writing table edge (13) permitting a person to sit in a mainly shadowed area and free from glare when he is outside said writing table edge (13). <IMAGE>

Description

SPECIFICATION Lighting device for lighting writing tables or similar work tables The present invention refers to a lighting device for illumination of writing tables orsimilarworktables said lighting device comprising one or several light fittings with light emitting parts, which has a reflector and a fluorescent tube provided therein, said reflector being provided to throw light towards a working surface situated at such an edge of a writing table at which a person isto be seated during performing work at the working surface, said reflector being further provided to th row the light in such a manner thatthe working surface and/or papers orthe like being placed thereupon will reflect said light sub stantiallyawayfrom said person.

Lighting devices ofthe kind referred to have proved useful in many instances but they do notfulfil all requirements,forexamplewhen it is desired: (A) thatthe lighting device is to followthework table if the latter is moved, which means that light ing device which is originally properly located relative to the work table as regards a non-glare illumination will be correctly placed independent of how and where to the work table is moved; (B) thatthreesides oftheworktableare leftfree, ie. three sides lack columns which may be hindering; (C) thatthe person mayworkin a non-glare and pleasant lightwithout having to sit in it; (D) that right-handed as well as left-handed persons may work without creating undesired shadows;; (E) that the same fluorescent tube is used to emit effective light downwards as well as upwards; (F) that the light fitting does not receive sufficient rigidity to extend from the column and hang freely along the entire edge ofthewriting table.

The object of the present invention is to provide an illumination device which fulfils all ofthe requirements referred to.

According to the invention, a lightingdeviceforil- luminating writing tables orsimilarworktables and comprising one or several light fittings having light emitting parts, comprises a reflector and a fluorescent tube arranged therein, said reflector being provided to throw lighttowards a working surface located at such a writing table edge where a person is to sitwhen performing work at the working surface said reflector being further provided to throw the light in such a mannerthattheworking surface andl or papers orthe like lying upon the same will reflect this light substantially away from said person, wherein one ofthe end portions of the light fitting is secured to a column which is arranged atthewriting table at the side of the working surface, the lightfitting is so arranged that the light emitting parts thereof with the fluorescent tube and the reflector are located substantially above said writing table edge, the reflector is asymmetrically shaped and designed so asto throw lighttowardstheworking surface located in front of said edge ofthewriting table causing said person to be in a substantially shadowed area when he is at the outer side of said writing table edge, the light emitting parts ofthe light fitting extend along a central part of the working sur face and at least somewhat longer at each side of the same and along the entire orat least almostthe en tire writing table edge causing outer portions ofthe light emitting parts to be located at both sides ofthe central part and provided to throw light against the working surface in such a mannerthatsaid lightwill hit the working surface and/or papers orthe like thereon at both sides of the central parts and further from both sides fall obliquely downwards towards the central parts and be reflected by the latterand/or papers orthe like lying thereupon in a direction away from the person offering the person a non-glare lighting which is free from undesired shadowcreation independentofwhetherthe person is right handed or left-handed.

The lighting device according to the invention provides among otherthings a non-glare lightand eliminates undesired creation of shadows during writing independent ofwhetherthe person using the able is right-handed or left-handed.

The invention will now be described in more detail with reference to the accompanying drawings in which: Figure 1 is a perspective view illustrating a lighting device according to the invention arranged at a writ ingtable; Figure2 is a side view ofthe lighting device of Figure1; Figure 3 is a rear view of the lighting device of Figure 1; Figure 4 illustrates the lighting device of Figure 1 on an enlarged scale; Figure 5 is a perspective view obliquelyfrom above of a light fitting forming part of the lighting device; Figure 6 is a view obliquely from below of the light ing deviceaccording to Figure 5; and Figure 7is a section through said lightfitting.

The lighting device illustrated in the drawings comprises a lightfitting 1 which is supported buy a column 2, which by means of a holding device 3 is arranged on a writing board 4.

The holding device 3 has the appearance of a cclamp, ie. it has a U-shaped portion 5 which is intended to embrace the edge ofthe writing table. The Ushaped portion 5 is secured by means of a screw 6 which from below may be screwed against the under side ofthewriting table edge oragainsta part7 underlying the writing table edge and is intended to protect the writing table edge and/or to distribute the load impressed upon it by the light fitting 1. The column 2 may have a sideways directed arm 8which supportsthelightfitting 1 andthelightfitting 1 may be connected to this arm 8 by means of an oscillation damping means 9 which is intended to counteract transmission of such vibrations or the like from the writing table4via the column 2tothe lightfitting 1, to which the writing table 4 is exposed when in use.

The column 2 is arranged in such a manneratthe writing table 4that the light emitting parts 10ofthe lighting device, ie. the fluorescent tu bell and the reflector 12 extend substantially along the writing table edge 13 at which a person 14 should sitwhen working ataworking surface 15. By locating the light fitting 1 in this mannerthe light emitting parts 10 thereofwill emitlightbeams 16 in the direction ofthe working surface 15 in such a mannerthat papers or the like lying upon it will reflect the light beams 16 in a direction away from the person 14.

The lightfitting 1 and the light emitting parts 10 thereof have such a length that outer portions 1 Oa, 1 Ob are situated at each side of such central parts 1 5a ofthe working surface 15 which constitutes the substantial working field ofthe working surface 15 for the person 14. The outer part 1 0a also emits light beams 17, 18 from which the light beams 17 are directed substantially downwardly such that they hit the working surface 15 and/or papers thereon to the left of the central parts 1 5a, while light beams 1 8 are directed obliquely downwards towards the central parts 15a,which reflectthem in a direction away from the person 14.The outer part 10b also emits light beams 19 and 20 from which the light beams 19 are directed substantially downwardly such thatthey will hit the working surface 15 and/orpaperthereon to the right ofthe central parts 15a, while the light beams 20 are directed obliquely downwards tow- ardsthe central parts 1 5a, which reflect them in a direction awayfrom the person 14 (see Figure 3). For explanatory purposes only the main light beam directions ofthe outer portions 1 Oa,1 Ob have been shown and the light beams which are directed downwards from the central portion 1 Oa of the light emitting part 10 have been omitted in Figure 3.

Owing to the fact that the light emitting parts 10 of the light fitting 1 emit light in the manner just described the light beams will illuminate the working surface 15 and especially the central parts 1 5a ofthe working surface at both sides of the hand which the person 14 use in his writing work independent of whether he uses his right or left hand. This is true as long as the person 14 moves his hand towards the central parts 15a and the working area 15 probably with the exception of the outermost parts ofthe working area 15. Also shadows created by writing implements are eliminated completely or in part.

Since the light emitting parts 10 ofthe light fitting 1 are so arranged and/or shaped thatthey will throw substantiallyall lighttoan area located infrontofthe said edge of the writing table 13 (ie. substantiallythe writing area) there is attained behind the writing table edge 13 (ie. substantially outside the writing area) an area within which there resides substantial shadow. This means that the person 14may with- draw himselffrom the lightfield simply by leaning back (see Figure 2).This special light field may for instance be generated by giving the light emitting parts 10 an asymmetrical reflector 12 having rear parts which throw light beams 21 straight down wardstowardstheedge 13 or parts ofthewriting table 4 just atthe edge 13 but not backwardly, other reflector parts throwing other light beams in a direction downwardly/forwardly (see Figure 2).

The light emitting part 10 has two end pieces 22,23 from which one end piece 22 is connected to the arm 8 ofthe column 2, for instance via the vibration damping part 9. At the end pieces 22,23 there are provided reinforcing profiles 24, 25 which extend along the light emitting part 10 intermediate said end pieces 22,23. The reinforcing profiles 24,25 extend in such a distance from each otherthatthere is generated between them and in the upper part an open slit 26. The reflector 12 is located intermediate the reinforcing profiles 24,25 and preferably is releasable therefrom.A screen 33 is positioned beneath the reflector 12 and preferably held secured to the reinforcing profiles 24,25 by means of a locking element 27 which is provided at the lower part of one ofthe reinforcing profiles 24 or 25 probably buy a further locking element28 at the reinforcing profile 24. Each locking element 27 and/or 28 comprises a profile which is pivotally mounted on edges 29 ofthe respective reinforcing profile 24 or 25. The profile may be locked to the end pieces 22,23 in an upswung locking position (drawn in full lines in Figure 7) and may be swung down to a release position (shown in dash-dotted lines in Figure 7) for releasing the screen 33 such that it can be dismantled by being removed in a downwards direction.

The reflector 12 preferably is made from light transmitting material 30, which atthe side facing the fluorescent tu bell and/or the side facing awayfrom the fluorescent tube 11, exceptfor an area 31 located above the fluorescenttube, is coated with a light reflecting material 32. The area 31 is located at the slit 26 such that lightfrom thefluorescenttube 11 will be transmitted in an upwards direction.

The invention is not limited to the embodiment described and shown above but may be varied within the scope of the appended claims. Thus the upper parts including the area 31 ofthe reflector 12 prefer- ably may be completely or partly located above the slit 26 and the lighting device may consist of one or several light fittings which may be arranged at the writing table 4 or at another working table to be illuminated. In order to counteract the transmission of vibrations from the writing table 4to the light fitting 1 morethan one damper9 may be arranged and one several dampers may be housed in the column 2 itself. The construction and location oftheholderde vice may bevaried; in rectangularwriting tables 40f the illustrated type it is preferably provided at one short side ofthe writing table edge.

Claims (8)

1. Lig hting device for il l uminating writing tables orsimilarworktablesandcomprisingoneorseveral light fittings having lightemitting parts, comprising a reflector and a fluorescent tube arranged therein, said reflector being provided to throw light towards a working surface located at such a writing table edge where a person is to sit when performing work at the working surface, said reflector being.further provided to throw the light in such a mannerthatthe working surface and/or papers orthe like lying upon the same will reflect this light substantially away from said person, wherein one of the end portions of the lightfitting is secured to a column which is arranged at the writing table atthe side of the working surface, the light fitting is so arranged thatthe light emitting parts thereof with the fluorescent tube and the reflector are located substantially above said writing table edge, the reflector is asymmetrically shaped and designed so asto throw lighttowards the working surface located in front of said edge of the writing table causing said person to be in a sub stantiallyshadowed area when heisattheouterside of said writing table edge, the light emitting parts of the light fitting extend along a central part ofthe working surface and at least somewhat longer at each side ofthe same and along the entire or at least almostthe entirewriting table edgecausing outer portions of the light emitting parts to be located at both sides of the central part and provided to throw lightagainsttheworking surface in such a manner thatsaid lightwill hittheworking surface and/or papers or the like thereon at both sides of the central parts andfurtherfrom both sides fall obliquely downwards towards the central parts and be reflected bythe latterand/or papers orthe like Iyingthere- upon in a direction away from the person offering the person a non-glare lighting which is free from undesired shadow creation independent of whether the person is right-handed or left-handed.

2. Lighting device according to claim 1, wherein the reflectorconsists of or includes lighttransmitting material which, except for a section above the fluorescent tube, comprises a light reflecting material causing the section above the fluorescent tube to transmit light from the fluorescent tube in an upwards direction.

3. Lighting device according to claim 2,wherein the light emitting part has two end pieces, one con- nected to the column and the other in the length direction ofthe light emitting part extending reinforcing profiles between them, and wherein the reflector is detachably mounted between the reinforcing profiles and upper parts ofthe reflector have the light transmitting section thereof situated at a slit between the reinforcing profiles.

4. Lighting device according to claim 3, wherein the upper parts of the reflector having the light trans- mitting section are located abovetheslit.

5. Lighting device according to claims 3 or4, wherein at least one ofthe reinforcing profiles at the lower end thereof has a locking element which in a locking position is intended to support a screen positioned beneath the reflector between the profiles and is intended to be moved out of its locking position for releasing the screen from its position between the reinforcing profiles.

6. Lighting device according to any the preceding claims, wherein the light fitting and/orthe column has one or several vibration damping means intended to counteract the transmission of such vibrations orthe like from the writing table viathe column to the light fitting as are acting upon thewrit ingtablewhen in use.

7. Lighting device according to claim 6, wherein thevibrationdamping means,oroneofthevibration damping means, comprises a connecting piece of rubber material orsimilarelastic material by means of which the light fitting is secured to the column or to an arm projecting sideways therefrom.

8. Lighting device substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.