EP0826920B1

EP0826920B1 - Luminaire for line illumination

Info

Publication number: EP0826920B1
Application number: EP19970201960
Authority: EP
Inventors: Hans Hermann Jämmrich; Bernd Stigrot; Wolfgang Henze; c/o Internationaal Octrooibureau Gert Winkler
Original assignee: Koninklijke Philips Electronics NV
Current assignee: Koninklijke Philips NV
Priority date: 1996-08-28
Filing date: 1997-06-26
Publication date: 2006-08-30
Anticipated expiration: 2017-06-26
Also published as: EP0826920A2; EP0826920A3

Description

The invention relates to a luminaire for line illumination, comprising:

a first trunk with a top wall;
an elongate light carrier having an outer surface which comprises means for accommodating and supplying an electric lamp, detachably fastened to the trunk;
a trunk-shaped coupling member with a longitudinal direction, a top wall, and side walls for connecting the first trunk in line to a second, adjoining trunk, the coupling member partly overlapping the first and the second trunk and comprising means for securing it to the first trunk.

Such a luminaire is known from DE-A-32 14 595.
In the known luminaire, the coupling member is present in the trunks, supported in flanged rims thereof. Projections are present at the top wall of the coupling member which are rotatable about an axis parallel to the top wall by means of a handle and which are capable of pressing against the top walls of the trunks. Owing to the deformations caused thereby, bulges in the side walls of the coupling member will press against the side walls of the trunks, so that these trunks are retained with clamping force.
It is a major disadvantage of the known luminaire that the coupling member leads to a substantial local narrowing of the trunks. This means that the trunks must be constructed with greater volume than if the coupling members were absent. It is another disadvantage that deformations must be realized in the coupling member and/or the trunk for rendering the bulges effective. There is a risk of deformations of the trunk becoming visible.
A coupling member for trunks is known from US-A-3 275 355 which comprises two mutually opposed U-shaped bodies projecting through one another whose bottoms can be pulled towards one another by means of screws so that the bodies will be clamped in the trunks. The coupling member is very voluminous, also because of a reinforcement provided therein.
A coupling member is known from DE-U-1 693 140 which comprises a U-shaped body and a loose plate cooperating therewith which are pressed apart from one another in trunks by means of screws so as to achieve clamping action. It is a substantial disadvantage that the coupling member is formed by two loose components and that screws are to be tightened or loosened inside the trunks.
It is an object of the invention to provide a luminaire of the kind described in the opening paragraph in which the coupling member occupies little space in the trunk and yet is of a simple, sturdy construction which is easy to operate.
According to the invention, this object is achieved in that the coupling member has inwardly flanged portions extending in longitudinal direction at its side walls, the coupling member hooks with clearance around the exterior of the first trunk with said inwardly flanged portions, and the coupling member has a resilient member which is fastened to the top wall, which is laterally rotatable, and which clamps against the top wall of the first trunk, substantially releasing said top wall upon a lateral rotation.
The coupling member of the luminaire is not present on the inside, but on the outside around the trunk, so that it does not occupy any space inside the trunk and allows a free passage to any elements extending through the trunk, such as electric cables. The coupling member may hook entirely around side walls of the trunk with its flanged portions, for example flanged rims, or around a profile extending in longitudinal direction of the trunk, for example an external or internal fold or rim. A resilient member is present at the top wall of the coupling member, pressing against the top wall of the trunk and thus retaining this trunk, and capable of rotation about an axis transverse thereto along the top wall to laterally of the trunk so as to release the latter. This means that the resilient member can be operated from outside the trunk.
The resilient member may press on the trunk in the extended direction of the coupling member, but alternatively the coupling member may have a split, for example in the shape of an arc of a circle, in its top wall through which the resilient member can project into the coupling member.
It is favorable, however, when the resilient member is fastened to the top wall of the coupling member inside this coupling member. The resilient member may then project to the exterior at an end of the coupling member. This embodiment has the advantage that the top wall of the coupling member supports the resilient member, so that the latter may be of a lighter construction. Another advantage is that the connection of the resilient member to the coupling member is less subject to tensional stresses.
The coupling member renders it easy to introduce a second trunk into the coupling member after the latter has been fixed around the first trunk by means of the resilient member. The trunks are then coupled transversely to their longitudinal direction. It is favorable when the resilient member also presses against the top wall of a second trunk, if present. The trunks are then coupled also in their longitudinal direction.
A preferred embodiment is characterized in that windows are present in the coupling member through which the resilient member can be rotated. The coupling member may then have a comparatively short length, and pressure application points of the resilient member against the top wall of the trunk and the top wall of the coupling member may then lie comparatively close together, so that a resilient member of low rigidity can be used.
It is favorable when a separate resilient member is present for the second trunk. The coupling member may then be fixed around the first trunk to facilitate the insertion of a second trunk, while this second trunk nevertheless can be coupled also in its longitudinal direction.
It is favorable when the resilient members substantially have an axis of symmetry where they are fastened to the coupling member. The resilient members are then symmetrically loaded. The connection between the resilient members and the coupling member then has an even better stress relief. The clamping force on both the trunk and the coupling member can be enhanced. It is also ensured thereby that the trunk is symmetrically pressed home into the coupling member. At the same time the operation of the coupling member during mounting and dismantling is facilitated.
In a favorable embodiment, the resilient member has a flanged rim which lies permanently at the exterior of the trunk-shaped coupling member. This rim is favorable for the purpose of pushing against it or pulling at it during mounting or dismantling of the coupling member. The rim may be flanged towards the top wall or away from the top wall.
In a favorable modification, the flanged rim is sleeve-shaped and extends to beyond the top wall of the coupling member. A pin or rod, for example a screw driver, may then be inserted into this sleeve so as to form a lever for operating the resilient member. In particular, the flanged, sleeve-shaped rims of each resilient member widen in a direction towards one another and lie at least partly in one another's extended direction. It is easy in this modification to insert a rod through the one flanged rim of a resilient member into the other one, whereby the operation is rendered even easier.
An embodiment of the luminaire according to the invention is shown in the drawing in which

Fig. 1 shows a luminaire in perspective view;
Fig. 2 shows the trunk-shaped coupling member with the trunks of Fig. 1 in perspective view;
Fig. 3 shows the trunk-shaped coupling member of Fig. 2 prior to its assembly; and
Fig. 4 shows the resilient member as viewed along IV in Fig. 3.

In Fig. 1, the luminaire for line illumination has a first trunk 1 with a top wall 10. An elongate light carrier 2 has an outer surface 20, comprising means 21 for accommodating and supplying an electric lamp, a tubular fluorescent lamp in the Figure. The light carrier 2 can be detachably fastened to the trunk 1 by means of a fastening member 22. The luminaire has a trunk-shaped coupling member 3 with a longitudinal direction, a top wall 30, and side walls 31, see Fig. 2, for connecting the first trunk 1 to a second, adjoining trunk 1' in one line, partly overlapping the first 1 and the second trunk 1'. The coupling member comprises means for fixing it to the first trunk 1.
The coupling member 3 has inwardly flanged portions 32, an inwardly flanged rim in the Figure, at its side walls 31, which portions extend in longitudinal direction. With these rims the coupling member 3 hooks with clearance around the outside of the first trunk 1, in the Figure around an inward fold 11 thereof. The coupling member 3 has a resilient member 4 which is fastened to the top wall 30, which is laterally rotatable, and which clamps against the top wall 10 of the first trunk 1, see Fig. 4, releasing this top wall 10 substantially upon a lateral rotation.
The resilient member 4, see Fig. 2, is fastened inside the coupling member 3 to the top wall 30 thereof, for example with staples, rivets, or pop rivets 34 in the Figure, see Fig. 3.
If the trunk 1 were to project less far into the coupling member in Fig. 2, the relevant resilient member 4 could also hold the second trunk 1' by clamping against the top wall 10 thereof.
Windows 33 through which the resilient member 4 can be rotated are present in the coupling member 3, see Fig. 3.
A separate resilient member 4 for the second trunk 1' is present in Fig. 2.
The resilient members 4, see also Fig. 3, substantially have an axis of symmetry 40 where they are fastened to the coupling member 3.
A flanged rim 41 is present at the resilient member 4, which rim permanently lies at the exterior of the trunk-shaped coupling member 3, both in the clamping position, on the left in Fig. 2, and in the non-clamping position, on the right in Fig. 2.
The flanged rim 41 in the embodiment shown is sleeve-shaped and extends to beyond the top wall 30 of the coupling member 3, see Fig. 2. The flanged rims 41 of the resilient members 4 widen in directions towards one another and lie at least partly in one another's extended direction, so that a rod can be inserted through the two sleeve-shaped flanged rims 41 so as to operate the member 4.
The coupling member 3 has a central opening 35 through which an electric cable can be passed to the interior, or in which a suspension member can be fastened for connecting the coupling member to a ceiling.
Fig. 4 shows the functions of the resilient member 4, for example made of spring steel, see also Fig. 3. The resilient member 4 has a central portion 42 which rests with its upper side (Fig. 4) against the top wall 30 of the trunk-shaped coupling member 3 with rotation possibility and is connected thereto. A guiding surface 47 for a trunk 1 merges into this, with a level difference. When the trunk 1 is introduced into the coupling member 3, a ramp 43 leads the trunk 1 towards the guiding surface 47. The resilient member has a resilient tongue 44 with an upper 45 and a lower bend 46, which at the same time form pressure application points. The resilient member 4 is shown in the unloaded state in Fig. 4. The upper pressure application point 45 projects above the central portion 42. The lower pressure application point 46 lies practically in the guiding surface 47. When the resilient member 4 is rotated into the trunk-shaped coupling piece 3 for fixing the trunk 1 by means of a pressure exerted on the flanged rims 41, the lower pressure application point 46 initially slides without substantial friction over the top wall 10 of the trunk 1 until the resilient tongue 44 hits against the top wall 30 of the coupling member 3. Then any clearance between the coupling member 3 and the trunk 1 is eliminated, and the resilient tongue 44 is pressed into a flatter shape until the upper pressure application point 45 presses against the top wall 30 of the coupling member 3. The two pressure application points 45, 46 lie comparatively close together.

Claims

A luminaire for line illumination, comprising:
a first trunk (1) with a top wall (10);

an elongate light carrier (2) having an outer surface (20) which comprises means (21) for accommodating and supplying an electric lamp, detachably fastened to the trunk (1);

a trunk-shaped coupling member (3) with a longitudinal direction, a top wall (30), and side walls (31) for connecting the first trunk (1) in line to a second, adjoining trunk (1'), the coupling member (3) partly overlapping the first (1) and the second trunk (1') and comprising means for securing it to the first trunk (1),
characterized in that the coupling member (3) has inwardly flanged portions (32) extending in longitudinal direction at its side walls (31), the coupling member (3) hooks with clearance around the exterior of the first trunk (1) with said inwardly flanged portions (32), and the coupling member (3) has a resilient member (4) which is fastened to the top wall (10), which is laterally rotatable, and which clamps against the top wall (10) of the first trunk (1), substantially releasing said top wall (10) upon a lateral rotation.
A luminaire as claimed in Claim 1, characterized in that the resilient member (4) is fastened to the top wall (30) of the coupling member (3) inside this coupling member (3).
A luminaire as calimed in Claim 1 or 2, characterized in that the resilient member (4) also presses against the top wall (10) of a second trunk (1'), if present.
A luminaire as claimed in Claim 2 or 3, characterized in that windows (33) are present in the coupling member (3), through which windows the resilient member (4) can be rotated.
A luminaire as claimed in Claim 1 or 2, characterized in that a separate resilient member (4) is present for the second trunk (1'), and windows (33) are present through which the resilient members (4) can be rotated.
A luminaire as claimed in Claim 5, characterized in that the resilient members (4) substantially have an axis of symmetry (40) where they are fastened to the coupling member (3).
A luminaire as claimed in Claim 4, characterized in that the resilient member (4) has a flanged rim (41) which lies permanently at the exterior of the trunk-shaped coupling member (3).
A luminaire as claimed in Claim 7, characterized in that the flanged rim (41) is sleeve-shaped and extends to beyond the top wall (30) of the coupling member (3).
A luminaire as claimed in Claim 6 and 8, characterized in that the flanged rims (41) of each resilient member (4) widen in a direction towards one another and lie at least partly in one another's extended direction.