Luminaire

Abstract

 Luminaire for a tubular discharge lamp having an elongate thin-walled housing (1) having at its end fittings (8, 9) for accommodating the lamp, the housing furthermore comprising at least an electric component for operating the lamp, for example an electric stabilisation ballast (14), the space limited by the housing (1) being filled with cured foamed plastics material (7), the wiring embedded in the foam having two parallel wires (10, 11), for each lamp to be accommodated, a first wire (11) being interrupted between connecting means (12, 13) of a component (14), said means (12, 13) being located on an imaginary line which coincides with the said wire (11).

Description

[0001] The invention relates to a luminaire for a tubular discharge lamp having an elongate thin-walled housing which at its ends is provided with end partitions which are arranged substantially transversely of the longitudinal axis of the housing, at least one electric component for operating the lamp being provided in the space limited by the wall of the housing and the end partitions, said housing having wires for connecting the component and the lamp to be placed in the luminaire to a power line, the space limited by the housing and the end partitions being filled with cured foamed plastics material. Such a luminaire is disclosed in DE-OS 1,914,094.

[0002] The above-described luminaire is used as a carrier of tubular discharge lamps, which as low-pressure mercury vapour discharge lamps. Such lamps are frequently used for general lighting purposes (for example in offices etc.), but also for special purposes, for example, for irradiating people, animals or plants. A thin-walled lumin- sire filled with cured foamed plastics material and having thin walls, for example sheet metal is very easy to handle owing to its comparatively lowweight. An electric component required for operating a lamp to be fitted in the luminaire is understood to mean, for example, an electric component for stabilizing a discharge lamp (an electric stabilisation ballast), a starter or a capacitor. Electric wires are provided in the housing to connect the lamp and one or more of the components to power mains. The component(s) and the wires are embedded in the foam. During the manufacture of the luminaire described in the above-mentioned Offen- legungsschrift, a trough with a generally U-shaped cross-section in which the components and the associated electric wires are provided is the starting point. Thereafter the U-shaped trough is provided with end partitions and is closed with a metal lid, whereafter, via an aperture in the lid or in the wall of the U-shaped trough foamed plastics material is injected into the space enclosed by said walls. Thereafter the liquid compound flows into the housing and cures to form a foamed solid material.

[0003] Positioning the components in the U-shaped trough and wiring them as well as connecting the wires to the terminals of the components is a complicated and time- consuming procedure.

[0004] .It is an object of the invention to provide a luminaire which is easy to handle and is of such a shape that its manufacture can be mechanized in a simple way so that it is suitable for mass-production.

[0005] According to the invention, aJuminaire of the type defined in the opening paragraph is characterized in that the wiring for each lamp to be accommodated in the luminaire is formed by two electric wires extending between the end partitions of the housing substantially parallel with the longitudinal axis of the housing and embedded in the foam, a first wire being interrupted at least between two current-connecting means of a component, said current-connecting means being located on an imaginary line which coincides with the first wire, the housing comprising means which cooperate with fittings for the accommodation of the lamp, said fittings having current connecting means which are electrically connectable to the parallel wires.

[0006] A luminaire in accordance with the invention can be mass-produced in a simple way.

[0007] The luminaire is formed and dimensioned such that the manufacture of the thin-walled housing, the provision of the wiring and the components and connecting the components to the wiring as well as filling the housing with foamed plastics material can be easily integrated in one mechanized procedure. Then no special measures, such as the temporary fixation of the wires and the components in the housing (for example during establishing the connection between the connecting means of the components and the wiring or during foaming) are not necessary.

[0008] The connecting means of the components are, for example, in the form of thin metal horseshoe-shaped piercing contacts (of a type, as described in, for example German Gebrauchsmuster 7508503). Such means are eminently suitable for usedn a mechanized manufacturing process for high-speed interconnections of the components and wires. The junctions between the connecting means and the wire are wholly embedded in the foam. They are consequently little vulnerable to vibration etc. The use of a special cover plate of the housing, as is described in the said DE-OS 1,914,094 is not necessary. The thin-walled housing of a luminaire in accordance with the invention has preferably a U-shaped cross-section so that during manufacture the housing can be positioned around the components and the wires. In addition, it is easy to inject an accurate dose of the foam (as a liquid) in the space limited by the wall of the housing and the end partitions.

[0009] The housing comprises means whereby fittings to accommodate the lamp are so connected to the housing that an electric contact with the wires is established. For that purpose the wall of the housing is provided with, for example special apertures of such a shape that the fittings can be locked in the apertures, In a practical embodiment the end partitions have double walls in which the fittings may be accommodated.

[0010] The fittings to accommodate the lamp can be connected by a user, as separate components, in a detachable manner to the housing, for example by means of a snap connection. However, the fittings may alternatively be connected to the housing during the manufacturing process.

[0011] In one embodiment of a luminaire in accordance with the invention the fittings may be connected, depending on the positions of the component, in comparatively randomly- selected positions (depending on the length of a lamp to be fitted in the luminaire) to the housing. In a practical embodiment the housing is of such a shape that when providing the fittings at the ends near the end partitions, several tubular low-pressure discharge lamps of a standardized length can be accommodated in the luminaire. In a special embodiment the housing serves as a mounting channel for a pendant luminaire.

[0012] In a luminaire in accordance with the invention the first electric wire is interrupted between connecting means of a first component, such as the electric stabilisation ballast. In a practical embodiment, to accommodate a second component being a unit (for example consisting of plastics material) provided with metal current connecting pins as means for connection to a power supply mains of, for example, the ballast and the fittings, the first wire is also interrupted in a different place between the two current connecting terminals of said unit. Lamps which can start without the aid of a starter are suitable for such a luminaire. To accommodate many low-pressure mercury vapour discharge lamps for general lighting purposes there is, however, in one embodiment an interruption in the second wire between current connecting means of a starter. The starter is, for example, provided in a special unit, the said interruption being located between current connecting means of said unit for the electrical and mechanical connection to the second wire. These current connecting means are located on an imaginary line which coincides with the second wire.

[0013] The invention will now be further described by way of example with reference to the accompanying drawing which shows an embodiment of a luminaire in accordance with the invention,

[0014] In the drawing:

Fig. 1 is a perspective view of a luminaire and

Fig. 2 shows diagrammatically the wiring and the associated components in a luminaire in accordance with Fig. 1.

[0015] The luminaire shown in Fig. 1 comprises an elongate housing 1 which is a trough with a U-shaped cross-section. The wall 2 of the housing is made from pre-lacquered steel or aluminium and in a practical embodiment is approximately 0.2 mm thick. The edges 3 and 4 situated near the open side are folded inwards. At its ends the housing has end partitions 5 and 6 which are positioned substantially transversely of the longitudinal axis of the housing. In the space limited by the wall of the housing and the final partitions there is a quantity of a cured foamed plastics material 7 which extends to the open side. The luminaire shown is suitable to accommodate one lamp (not shown) which is supported by two fittings 8 and 9. A number of electric components and also the wiring for connecting said components and the lamp in the luminaire to a power mains are embedded in the foam. Since only one lamp can be placed in the luminaire-shown, the wiring consists of two electric wires 10 and 11 which between the end partitions 5 and 6 extend in parallel with each other and with the longitudinal axis of the housing and are embedded in the foam. A first wire (denoted by 11) is interrupted between two terminals 12 and 13 of a first electric component, namely the electric stabilisation ballast 14 (formed from a plurality of windings of insulated copper wire around a laminated iron core). In addition, wire 11 is interrupted between two connecting means 15 and 16 of a second component, namely the unit 17, which supports the current connecting pins 18 and 19 for the power mains. Finally, an interruption is provided in wire 11 between terminals 20 and 21 of a third component, namely the capacitor 22. The said terminals are in the form of metal horseshoe-shaped piercing terminals, in which electric contact with a copper core of wire 10 or 11 is made by piercing through the insulation which is usually provided around the wire core. The terminals grip the copper core and are not detachable. The connections of wires and connecting means are wholly embedded in the foam.

[0016] Near the final partitions, via an aperture in the wall of the housing, the fittings 8 and 9 are electrically and mechanically connected to the wires 10 and 11 by means of elements 23 and 24 (fitting 8) and elements 25 and 26 (fitting 9).

[0017] In a practical embodiment the end partitions (5, 6) have double walls, it being possible to secure the fittings (8, 9) mechanically in the final partitions. At their ends facing the housing 1 the current supply means 23, 24, 25 and 26 located in the fittings are folded to a U-shape. When they are positioned in the final partitions an electric connection is made to the ends of the wires 10 and 11, which are connected in the end partition wall portions facing the foam and folded thereafter.

[0018] The current connecting means 24, 20, 21, 12, 13, 15, 16 and 26 are located on an imaginary line which coincides with the wire 11.

[0019] Wire 10 has only one interruption, namely between the terminals 27 and 28 of a starter 30 with associated anti-interference capacitor (not shown), see Fig. 2, which in a practical embodiment is included in unit 17. The terminals 27 and 28 of the unit by means of which the terminals of the starter are connected are located on an imaginary line which coincides with the wire 10. Also the current supply means 3 (of Fitting 8) and 25 (Fitting 9) are located on said imaginary line. The situation described in the foregoing is shown diagrammatically in Fig. 2.

[0020] It should be noted that in a luminaire which is suitable to accommodate, for example, two lamps, four parallel wires are provided in the housing. The housing then comprises two electric stabilisation ballasts, two starters etc.

[0021] A luminaire as shown in Fig. 1 can be made starting from two substantially parallel-extending electric wires formed from a copper core having a plastic material insulation. The length of the wires substantially corresponds to the length of the housing of the luminaire. The wires are thereafter connected in the final partitions (5, 6). Then the metal terminals of the capacitor are positioned on and connected to a first wire and the electric stabilisation ballast on that same wire. By means of the above-mentioned terminals which are in the form of piercing contacts the insulation of the wire is cut and the elements grip the copper core. Thereafter those portions of the wire which extend between the connecting means of a component are removed. In like manner, unit 17 which comprises the pins 18 and 19 for connection to the power supply and also comprises the starter 30 is positioned on the wires and the different portions between the connecting means 15, 16 and 27, 28, respectively are removed.

[0022] Thereafter the trough-shaped thin-walled housing is positioned so that it accommodates the wiring and the components, the wall of the ballast bearing substantially on three sides of the housing. Thereafter the end partitions are connected to the wall 2 of the housing, whereafter the housing is turned until the open side faces an injector of a foaming machine. The foam is injected in a measured quantity in liquid form, the injector moving along substantially the full length of the housing. After a comparatively short period of time the liquid material expands and cures, a uniform cellular structure being obtained. The foam has then adhered to the wall of the housing and to the components located therein. Also the wiring is wholly embedded in the foam. The density of the foam (consisting of polyisocyanurate foam in a practical embodiment) is comparatively low and its weight is correspondingly low. This procedure results in a luminaire having a housing which has a high degree of rigidity.

[0023] The luminaire may be fastened to a ceiling or a wall, for example by means of a metal support in the form of a plate. Said support may be fastened to a ceiling, for example by means of a screwed connection. The open side of the housing having a U-shaped cross-section faces the support and is fastened thereto in a detachable manner, for example by means of a snap connection.

Claims

1. A luminaire for a tubular discharge lamp having an elongate thin-walled housing which at its ends is provided with end partitions which are positioned substantially transversely of the longitudinal axis of the housing, at least one electric component for operating the lamp being provided in the space limited by the wall of the housing and the end partitions, said housing having wires for connecting the component and the lamp to be placed in the luminaire to a power line, the space limited by the housing and the end partitions being filled with cured foamed plastics material, characterized in that the wiring for each lamp to be accommodated in the luminaire is formed by two electric wires which extend between the final partitions substantially parallel with the longitudinal axis of the housing and are embedded in the foam, a first wire being interrupted at least between two connecting means of a component, said current connecting means being located on an imaginary line which coincides with the first wire, the housing comprising means which cooperate with fittings for the accommodation of the lamp, said fittings having current connecting means which are electrically connectable to the parallel wires.

2. A luminaire as claimed in Claim 1, characterized in that the second wire is provided with an interruption between two connecting means of at least a starter, said terminals being located on an imaginary line which coincides.with the second wire.

3. A luminaire as claimed in Claim 1 or 2, characterized in that the connecting means are in the form of horseshoe-shaped metal piercing contact.

4. A luminaire as claimed in Claim 1, 2 or 3, characterized in that the thin-walled housing has a U-shaped cross-section, the foam extending to the open side of the housing.

Drawing