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(11) | EP 0 870 981 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Luminaire for line illumination |
| (57) The luminaire for line illumination has a trunk (10) to which a light carrier (1)
is detachably fastened. The luminaire has a coupling member (20) inside the trunk
(10) for aligning said trunk (10) with an adjoining trunk (10'). The coupling member
(20) has a trunk-shaped coupling piece (21) with a top (22) at the outside of which
a tensioning disc (30) with a relief (31) is present, which tensioning disc can be
rotated by means of a rotation disc (40) present in the coupling piece (21) and coupled
to the tensioning disc. When rotated, the relief (31) of the tensioning disc (30)
is moved onto a relief (24) of the top (22) of the coupling piece (21). The coupling
piece (21) is pressed thereby with its sides (23) into flanged portions (15) of the
trunk (10) and is fixed therein in alignment with an adjoining trunk (10') which is
passed over the coupling member (20). |
[0001] The invention relates to a luminaire for line illumination comprising:
a first trunk with a top wall and side walls, which side walls each have a inwardly flanged portion which runs parallel to the top wall;
an elongate light carrier provided with an outer surface which has means for holding and electrically supplying an electric lamp, which carrier is detachably fastened to the trunk;
a coupling member having a longitudinal direction for connecting the first trunk to an adjoining trunk in line, such that the coupling member partly overlaps the first and the adjoining trunk and is provided with a trunk-shaped coupling piece which has a top alongside the top wall of the first trunk and which has sides which are present in the flanged portions of the side walls of the first trunk, said coupling member having fixation means for securing the coupling piece in the first trunk.
[0003] Studs are present at the top of the coupling piece in the known luminaire, which studs are rotatable about an axis parallel to the top by means of a handle and are capable of pressing against the top walls of the trunks. The deformations which occur then cause bulges in the side walls of the coupling piece to press against the side walls of the trunks, with the result that these trunks are tightly clamped in.
[0004] It is a disadvantage of the known luminaire that the coupling member causes a substantial local narrowing of the trunks. This means that the trunks have to be constructed more voluminously. Another disadvantage is that deformations in the coupling piece and/or the trunk are to be realized in order to render the bulges effective. There is a risk that the deformations of the trunk become visible.
[0005] A coupling member for trunks is known from US-A-3,275,355 and comprises two mutually facing U-shaped bodies which enter one another and whose bottoms can be urged towards one another by means of screws, so that the bodies will clamp themselves into the trunks. The coupling piece occupies much space, also on account of a reinforcement provided therein.
[0006] A coupling member is known from DE-U-1 693 140 and comprises a U-shaped body and a loose plate cooperating therewith, which components are forced away from one another by means of screws so as to have a clamping effect in trunks. It is a substantial disadvantage that the coupling piece consists of two separate parts and that screws are to be tightened or loosened inside the trunks.
[0007] It is an object of the invention to provide a luminaire of the kind described in the opening paragraph which is of a simple construction which occupies little space.
[0008] According to the invention, this object is achieved in that the coupling piece comprises a tensioning disc as the fixation means between its top and the top wall of the first trunk, which disc is coupled via an opening in the top to a rotation disc inside the coupling piece, the coupling piece having in its top a high relief which is directed towards the top wall so as to cooperate with a high relief of the tensioning disc which is directed towards the top.
[0009] The coupling member of the luminaire according to the invention is highly suitable for aligning mutually adjoining trunks with respect to one another and keeping them aligned, so that any staggered transition between adjoining trunks of luminaires, for example mounted in line against a ceiling, is prevented. The construction of the coupling member lends itself to a very slim design, the coupling member having a thickness of no more than, for example, approximately 10 mm against the top wall. The coupling member is also easy to apply and secure. The coupling member may be inserted into the trunk in the longitudinal direction and subsequently be secured by a small rotation of the rotation disc, for example through approximately 45° or 90°.
[0010] When the rotation disc is rotated, the tensioning disc is taken along and the relief of the tensioning disc is moved onto the relief of the coupling piece, with the result that the tensioning disc and the coupling piece together will assume a greater dimension transversely to the top wall and any clearance previously present is taken away from the coupling piece in the trunk, to the effect that the coupling piece will exert pressure in the flanged portions of the side walls while the tensioning disc presses against the top wall of the trunk.
[0011] In a favorable embodiment, the high relief of the top and of the tensioning disc is of a dual, symmetrical construction so as to obtain a symmetrical pattern of forces.
[0012] The tensioning disc and the rotation disc may be interconnected, for example, by means of rivets, hollow rivets, etc. It is convenient, however, when the discs are coupled to one another by means of tongues which project through slots and which have subsequently been deformed, for example have bent or twisted end portions. In an embodiment, the rotation disc has such tongues and the tensioning disc has such slots. In a favorable modification, the end portions of the tongues lie recessed each in a cavity. This has the advantage that they are not mechanically loaded when the rotation disc rotates the tensioning disc up against the top wall.
[0013] In a favorable embodiment which is easy to operate, the rotation disc has a slot by which it can be operated with a screwdriver.
[0014] The coupling member may be so used that the tensioning disc also presses against the top wall of an adjoining trunk. It is convenient for mounting purposes, however, when the tensioning disc acts only on the first trunk. An adjoining trunk may then be easily provided over the coupling member without the risk of shifting this member. It is favorable for an accurate alignment of two trunks, however, when the coupling member comprises separate fixation means for the adjoining trunk similar to those for the first trunk.
[0015] The luminaire may be suitable, for example, for accommodating one or several tubular lamps, such as fluorescent lamps.
[0016] An embodiment of the luminaire according to the invention is shown in the drawing, in which
Fig. 1 is an exploded view of the luminaire;
Fig. 2 is an elevation viewed along II in Fig. 1;
Fig. 3 is an elevation of the coupling piece viewed along III in Fig. 2;
Fig. 4 is a cross-section taken on the line IV-IV in Fig. 3;
Fig. 5 is a side elevation of the rotation disc;
Fig. 6 is an elevation viewed along VI in Fig. 5;
Fig. 7 is an elevation of the tensioning disc viewed along VII in Fig. 2; and
Fig. 8 is a cross-section taken on the line VIII-VIII in Fig. 7.
[0017] In Fig. 1, the luminaire for line illumination comprises a first trunk 10 with a top wall 11 and side walls 13 which each have an inwardly flanged portion 15 running parallel to the top wall 11. This portion 15 is an inward fold in the Figure which lies at a distance from an inwardly flanged lower rim 14 of the respective side wall 13. The lower rim 14, however, may itself be used for the same purpose. An elongate light carrier 1 having an outer surface 2 provided with means 3 for accommodating and supplying an electric lamp, a tubular fluorescent lamp in the Figure, is detachably fastened to the trunk 10. The light carrier 1 has for this purpose a member 6 at an inner surface 4, see also Fig. 2, comprising movable hooks 7 which rest on the flanged lower rim 14, see Fig. 2. A coupling member 20 having a longitudinal direction is present for connecting the first trunk 10 to an adjoining trunk 10' in line with one another, such that the coupling member 20 partly overlaps the first 10 and the adjoining trunk 10'. The coupling member 20 is provided with a trunk-shaped coupling piece 21 having a top 22 alongside the top wall 11 of the first trunk 10 and having sides 23 which lie within the flanged portions 15, i.e. the folds, of the side walls 13 of the first trunk 10. The coupling member 20 comprises fixation means for securely fastening the coupling piece 21 in the first trunk 10.
[0018] The coupling piece 21, see Fig. 2, has a tensioning disc 30 as the fixation means between its top 22 and the top wall 11 of the first trunk, which tensioning disc is coupled via an opening 25 in the top 22 to a rotation disc 40 inside the coupling piece 21. The coupling piece 21 has in its top 22 a high relief 24 which is directed towards the top wall 11, see also Figs. 3 and 4, so as to cooperate with a high relief 31 of the tensioning disc 30, see Figs. 7 and 8, which is directed towards the top 22. The high relief 24 for the tensioning disc 30 is present twice, along the sides 23. In Figs. 3 and 4, the relief 24 is formed by a stamped-out and folded strip against which the tensioning disc 30 can run up with its high relief 31 and which in the embodiment shown has a depression 24' near its highest point, in which depression the high relief 31 of the tensioning disc 30 can be held fixed.
[0019] The coupling member 20 aligns the trunks 10, 10' both in vertical and in lateral direction as a result of the downward pressure exerted by the tensioning disc 30 on the coupling piece 21, and thus on the trunks 10, 10', and as a result of the lateral force thus exerted by the coupling piece 21 on said trunks 10, 10'.
[0020] The tensioning disc 30 and the rotation disc 40 are coupled by means of tongues 41, present at the rotation disc 40 in the Figures, which project through slots 32, present in the tensioning disc 30 in the Figures, and which have deformed end portions 42, which end portions lie recessed in respective cavities 33 of the tensioning disc 30. The slots 32 are each placed in a cavity 33 for this purpose.
[0021] The rotation disc 40, see Fig. 6, has a central slot 43 by means of which this disc can be easily rotated with a screwdriver.
[0022] The coupling member 20 in the embodiment shown in Figs. 1 and 3 has separate fixation means for the adjoining trunk 10'. Openings 26 in the coupling piece 21 may serve to guide an electric cable into the trunks 10, 10' in those embodiments in which the trunks 10, 10' have corresponding openings.
a first trunk (10) with a top wall (11) and side walls (13), which side walls each have an inwardly flanged portion (15) which runs parallel to the top wall (11);
an elongate light carrier (1) provided with an outer surface (2) which has means (3) for holding and electrically supplying an electric lamp, which carrier is detachably fastened to the trunk (10);
a coupling member (20) having a longitudinal direction for connecting the first trunk (10) to an adjoining trunk (10') in line, such that the coupling member (20) partly overlaps the first (10) and the adjoining trunk (10') and is provided with a trunk-shaped coupling piece (21) which has a top (22) alongside the top wall (11) of the first trunk (10) and which has sides (23) which are present in the flanged portions (15) of the side walls (13) of the first trunk (10), said coupling member (20) having fixation means for securing the coupling piece (21) in the first trunk (10), characterized in that the coupling piece (21) comprises a tensioning disc (30) as the fixation means between its top (22) and the top wall (11) of the first trunk (10), which disc is coupled via an opening in the top (22) to a rotation disc (40) inside the coupling piece (21), the coupling piece (21) having in its top (22) a high relief (24) which is directed towards the top wall (11) so as to cooperate with a high relief (31) of the tensioning disc (30) which is directed towards the top (22).