NL1020377C2 - Light pipe, has multiple light sources connected to power cable extending through light casing - Google Patents

Abstract

The light includes a power cable (12) extending through the light casing (2) substantially in the length direction of the latter. Multiple light sources (1) are connected to the power cable and at least one is secured inside the light casing. The light casing is elongated and has a light emission surface provided with a light distribution means.

Description

Short indication: Lamp

The present invention relates to a lamp, comprising an elongated hollow lamp body with a light-emitting surface provided with light-distributing means, as well as a light source connected to the lamp body.

Such lamps are generally known, for example fluorescent tubes, whether or not incorporated in a luminaire, and more particularly also lamps which are known under the name "light-pipes". For example, US-A-5901266 discloses a light pipe of any length with a uniform surface brightness. This comprises a light source that radiates bundled light 10, and a module. On the inner surface of this module a light extraction mechanism is present which, depending on the distance along the module, emits a certain portion of the incident light outwards, such that the decrease in intensity of the incident light as a function of the distance to the light source is compensated.

The light pipe described, as well as the other known lamps of the type mentioned in the preamble, have the disadvantage that they are not very flexible, for example with regard to later adjustment of the brightness distribution. Although in principle any desired brightness distribution is possible with a light pipe, there are a number of limitations. Thus, only one light source, or at most two light sources, is used at the end (s) of the module or pipe. This means, for example, that if the light pipe should have a large length, the overall brightness level will be very low. In addition, the light extracting agent must be accurately calculated on the radiation profile of the light source of the module. The relative brightness distribution over the length of the module is then fixed and cannot be changed later.

The present invention aims to provide a need for lamps in which a greater freedom is provided when adjusting the relative brightness distribution, in particular the possibility of later modification. This is based on the; "; 2 U ^ i 1.

Realize that the almost absolutely homogeneous brightness distribution of a light pipe can in many cases also be approached in a different way, but many new design options can be provided.

The invention achieves the above-mentioned object in that the lamp also comprises a supply cable extending substantially through a longitudinal direction of the lamp body, and that a plurality of light sources are present which are each electrically connected to the supply cable and at least one of which is attached in the lamp body. Because a power supply cable extends in the lamp in substantially a longitudinal direction of the lamp body, there is a possibility of electrically connecting a light source at any desired location in that lamp body. Because the light sources are therefore no longer tied to the end or the ends of the lamp body, it is much simpler to obtain, for example, a higher light intensity because several light sources of lower power each can be used. This also implies better control of the thermal power. In addition, it is also simple to obtain a higher light intensity at any desired location by simply placing one or more additional light sources, or a stronger light source.

By "attached in the lamp body" is meant in the context of the invention that the light source in question is not placed at the end of the lamp body, that is to say that on both sides of the light source in question a part of the light emitting surface of the lamp body is present .

The supply cable is preferably included in a recess in the lamp body. Thus, in principle, the entire inner section of the lamp body remains available for the light sources and thus for the passage of the light emitted thereby. This ensures the smallest possible influence on the course of the light in comparison with a light pipe with light sources at the ends according to the prior art. The recess can for instance be designed as a groove or trough along the length of the lamp body 35 or over a part thereof. Nevertheless, it is also possible to install the power cable within the inner circumference of the lamp body. This offers the possibility of also converting existing light-pipes, or other bodies suitable for serving as a lamp body, into a lamp according to the invention. It is furthermore conceivable to attach the supply cable to the outside of the lamp body, for instance by means of an adhesive suitable for this purpose, wherein the electrical connection is established through the wall of the lamp body. The electrical connection means which are to establish the electrical connection must then penetrate the wall, wherein this wall preferably consists of a simply permeable material, for instance a plastic that is not too hard.

A favorable embodiment is characterized in that the supply cable comprises current conductors which are provided with insulation, and that the light sources are provided with connection pins which are adapted to pierce through the insulation so as to make electrical contact with the current conductors. Thus, a connection can be made between light source and power cable in a simple, fast and reliable manner. The connection pins are, for example, pins with a pointed point which can easily penetrate through the insulation of the power cable. If desired, one or more connecting pins can be provided with barb means for an even more reliable attachment to the current conductors. This is particularly the case with current conductors constructed as so-called litzen, each consisting of bundles of twisted metal fibers. Nevertheless, it is also possible to connect the light sources to the power cable in a different way, for example by means of crown stones, weld connections, etc.

The light sources are advantageously provided with first fastening means and the lamp body is provided with second fastening means which cooperate with the first fastening means. In this way, the light sources can also be simply mechanically connected to, i.e. attached to, the lamp body. This guarantees a constant illumination pattern and a greater stability of the lamp as a whole. A special embodiment is characterized in that the second fastening means comprise a recess extending in the longitudinal direction of the lamp body and that the first fastening means can be displaced in the second fastening means and can be fixed therein. The first fastening means in this case comprise, for example, a protuberance with a cross-section that can cooperate with the said recess. The first fastening means may, for example, comprise spreading pins or combinations of bolts and nuts, so that the light sources can simply be detached from the lamp body, moved and fixed again. Preferably the electrical connection between light source and supply cable must be disconnected prior to displacement, but in the case that the supply cable is loose in the lamp body, this is not always necessary. Said embodiment provides a lamp with stably placed light sources that can nevertheless be adjusted afterwards as desired.

In an advantageous embodiment of the lamp according to the invention, the light distributing means comprise a diffuser. The diffuser contributes to a more uniform brightness on the surface of the lamp body, so that the individual light sources can be perceived less clearly. The diffuser can be designed in all manners known in the art. For example, the diffuser comprises a structuring of the light-transmitting surface, for example in the form of scratches, pits of ridges and the like. The surface can also be sanded or etched, or provided with a layer of light-scattering material.

In another advantageous embodiment of the lamp according to the invention, the light distributing means comprise a prism film. In the context of the present invention, by "prism film" is meant: a film with such a structure that, if a piece of prism film is illuminated from the side with a bundle of collimated light, the surface of the prism film lights up substantially uniformly bright. Such prism films are used in particular in light pipes where they ensure uniform brightness. They often comprise a prismatic structure on the outside that extends over the length of the light pipe in such a way that, in lateral exposure, an increasing portion of the incident light is emitted on the outside of the light pipe. Thus, the amount of light presented to the prism film in the light pipe, which naturally decreases with increasing distance from the light source, can be compensated. Although the term "prism film" contains the word part 5 "prism", it is not necessary to use prism-shaped structures. An example of such a prism foil is the so-called OLF foil from the manufacturer 3M.

With the prism films, it is desirable to tune the structure, that is, the emitted fraction of the applied light 10 as a function of the distance, to the offered light. This is at least necessary in order to obtain a uniform brightness on the surface of the prism film. It is thus not possible, or only to a limited extent, to use other light sources or a different light distribution without losing the intended advantages of the use of prism foil. On the other hand, however, if the light sources are changed in number and / or light intensity, it is also possible to adapt the light distribution means used accordingly.

In an efficient embodiment of the lamp according to the invention, the prism film comprises at least two mutually parallel strips which are releasably arranged in the lamp body with the aid of retaining means. The strips can then be arranged in the lamp body and held at the desired location with the aid of the retaining means, for example ridges with a widened top. Parallel in this context may mean extended and / or side by side in each other. By making use of the above-described structure with at least two strips of prism foil, it is easy to adjust the lamp to the desired surface brightness. After all, a strip of prism foil can be chosen which is adapted to the light source used on site. An adapted strip can thus be used for each light source in the lamp according to the invention. In addition, it is independently possible to use several prism foil next to each other. This is advantageous, for example, if an unequal brightness of the lamp is desired all around. It is thus possible, for example, to obtain only one-sided light emission by providing one side of the lamp with a light source. opaque or reflective prism film, while the other side is provided with the normal, light-transmitting prism film. Of course, other broadcast angles are also possible. We will come back to this later.

The shape and design of the lamp are not particularly limited. For example, the lamp is a so-called light pipe, i.e. the lamp body is a more or less cylindrical tube. Other profiles, such as oval, square, etc., are also possible. The lamp body is expediently constructed in one piece.

Nevertheless, in a special embodiment of the lamp, the lamp body comprises a support part as well as an at least partially light-transmitting cap part, wherein the carrier part and the cap part are releasably attached to each other with the aid of cap fixing means. In this embodiment, the light-emitting surface thus comprises the light-transmitting cap part. With the aid of the support part the lamp can be attached to a support, a surface such as a wall, etc. For this purpose the support part is provided with suitable fastening means, such as screw eyes, whether or not already provided with screws, surfaces with adhesive, etc.

The above-mentioned construction has the advantage that, if, for example, maintenance or a modification of the light sources, the prism film, etc. is desired, the cap component can be detached from the carrier component. The light sources, the prism foil and possibly other parts present on the inside of the lamp body are thus easily accessible for maintenance, modification, etc.

Advantageously, the cap fastening means comprise a protrusion extending in the longitudinal direction of the cap part, which projection cooperates with a groove in the carrier part. Of course, in another suitable embodiment, the protrusion and the groove may be interchanged. In principle, the presence of one protrusion and of one groove is sufficient if a suitable complementary cap fastening means is present on the other side of the lamp body, for example a hinge or for instance hook parts. Advantageously, a groove or a protrusion is provided on either side of the hood component, and at corresponding locations on the carrier component resp. a protrusion or a groove present. In this way, the cap part and the carrier part can be fastened to each other quickly and reliably. Not only are no projecting parts present on the outside of the lamp, but moreover said construction can be so-called self-supporting. This means that the cap part and the carrier part can in principle be attached to each other with one hand by simply pressing each other, in particular if the cap fastening means are designed to be counter-releasing. The latter means that the distance between the aperture 10 of the groove and the hood attachment means, whether or not complementary, on the other side of the hood member is greater than the distance between the projection cooperating with said screw and the aforementioned hood attachment member, whether or not complementary. A certain resistance must then be overcome in order for the hood mounting means to engage. To this end, at least one protrusion and / or one groove are advantageously made from at least somewhat elastic material. Nevertheless, any other fastening means known in the art is in principle possible as a hood fastening means. Mention may be made, inter alia, of screws, spreading pins, adhesive, etc.

The cap component comprises very advantageously at least two sub-caps which can be detached from the carrier component independently of each other. Detaching in this context means that the relevant cap part can be moved relative to the carrier part. This may involve complete removal, but also pivoting open, shifting, etc. The advantage of the presence of at least two sub-caps is that the entire cap component does not have to be detached from the support component in one go. Particularly in the case of large and thus heavy hood parts, this could encounter great difficulties for persons who have to carry out work. By only detaching that partial cap from the supporting part that covers the relevant part of the lamp (e.g. light source, strip of prism film), the relevant activity can be carried out much more simply. The carrier part, on the other hand, does not have to consist of several parts, since this remains fixed in principle.

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In order to obtain an even more reliable attachment of the cap part to the carrier part, an additional fastening means can, if desired, be provided in the groove in which the protrusion is already present, for example a cord or the like.

By introducing this additional fastening means into the groove with some force, an additional clamping effect is created, which moreover seals the opening between cap part and carrier part better against, for example, penetrating moisture.

The carrier portion advantageously comprises a reflector. Particularly if the carrier part is mounted on a slightly extended support part, in particular a lamp, it is advantageous if any light emitted in the direction of that support part can be reflected in the direction of the light-emitting surface provided with light-distributing means. This naturally results in a higher useful light output. Among other things, a smaller or larger part of the carrier part can be provided with a reflector, if desired, a part of the cap part can also be provided with a reflector. In particular if the cap component as a whole defines a greater angle than is desired as a light-emitting surface, a part of the cap surface can be used as a reflective surface, so as to obtain an even higher light output. The reflector can be any reflective material used in the prior art, including reflective reflective material such as metals or polished minerals, but also stray light materials, such as finely divided titanium dioxide powder, etc.

In an advantageous embodiment, the reflector comprises a foil that at least partially covers the recess and the supply cable contained therein. Such a reflector can comprise the foil 30 in the form of a metal foil, which can thus reflect on itself, but the foil can also only be a carrier part of the reflective material of the reflector, for example titanium dioxide powder. A clear advantage of the presence of the reflector over the recess is that the recess mentioned in this way is accurately covered, so that the light propagating through the interior of the lamp body encounters as few obstacles as possible and is retained as much as possible in order to to be broadcast. Moreover, the supply cable can thus be effectively insulated and protected against any moisture and the like that penetrates through holes in the hood component, through gaps between hood component and support component, etc. In that case, of course, the reflector comprising metal foil should also comprise an electrically insulating layer. If desired, the reflector comprising a foil can run through at the location of the light sources. The connecting pins of the light source then penetrate the reflector. In the case of electrically conductive reflectors, including metal foils, additional insulation measures must of course be taken to prevent short-circuiting between connecting pins and reflector.

The lamp according to the invention preferably comprises light sources which radiate light in substantially a longitudinal direction of the lamp body. Thus, optimum use can be made of the properties of the light distribution means, and a desired homogeneity of the surface brightness of the lamp can be obtained. By "substantially a longitudinal direction of the lamp body" is meant that the main emission direction of the light coincides with a main axis of the lamp body. The light is then preferably bundled, with a beam angle that is, for example, a maximum of 15 °. However, other angles are not excluded.

Depending on the dimensions of the lamp body, all desired types of light sources can in principle be used as light sources. For example, light bulbs, high-pressure lamps, LEDs, etc. are possible. If desired, these light sources can be provided with associated reflectors, so that they can emit a light beam when properly aligned. For example, reflector filament lamps, reflector high pressure lamps etc. can also be used. However, it is not necessary for the light sources to emit light in substantially a longitudinal direction of the lamp body. Particularly if the light sources are small and are at a large distance relative to the dimensions of the lamp body, suitable diffuser means and the like can already provide a sufficiently homogeneous surface brightness.

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The light sources advantageously comprise an LED. Of the light sources mentioned above, LEDs offer the advantage of a high efficiency with a very long lifespan. This offers great advantages, especially in places where maintenance is difficult. LEDs can moreover be designed in all kinds of colors, and even as so-called white light LED. They are also easy to control, whereby their lifespan, unlike many other types of light sources, hardly or not at all.

In a special embodiment of the lamp according to the invention, the light sources comprise a light source housing which comprises a heat-conducting housing provided with cooling ribs for receiving a light-generating means and a cavity enclosed by the heat-conducting housing for accommodating light-generating means control means.

Such a light source is known from EP-A-0350522. The light source housing comprises a hollow heat-conducting body with electrical connection means, which can be connected to the base portion of a light-generating means with a reflector portion. Heat shield means in the form of a graphite foil form a thermal connection between the foot portion of the light generating means and the heat dissipation means, which are connected to cooling ribs on the housing. The foot portion of the light generating means thereby protrudes through the graphite foil.

If such a combination of light source housing and halogen incandescent lamp is designed as a compact lighting device, for instance for so-called light pipes or spotlights, the problem of a low light output in relation to the heat generated and thus a low efficiency occurs. Especially in closed housings, in which therefore no active cooling with outside air can take place, this low efficiency limits the maximum light output of the lighting device. Increasing the lamp power will result in such an increase in the amount of heat produced that the lamp life is unacceptably reduced or that there is even a risk of fire. Moreover, the light source housing, as described in EP-A-0350522, is not particularly suitable for those light sources that require high (ignition) voltages, including gas discharge lamps. There is a great risk of electrical breakdown with the graphite foil. There is thus a need for a light source housing that enables lamp operation with more efficient light sources.

The above disadvantages can be eliminated with a generally improved light source housing. To this end, the light source housing is characterized in that the heat-conducting housing is adapted to receive a gas discharge lamp and comprises a cavity enclosed by the housing for accommodating light-generating means for the light-generating means.

Such a light source housing suitably offers the possibility of accommodating a gas discharge lamp. With a gas discharge lamp, a higher light output can be achieved with constant heat development. To ensure safe and efficient light generation control, the cavity of the light source housing is arranged as close as possible to the gas discharge lamp. In this way it can be guaranteed that any light generating means control means and / or electrical connecting means to be arranged in the cavity are protected as well as possible against external influences, including moisture. Depending on the type of gas discharge lamp selected, the suitable light-generating means can be accommodated in the cavity. On the other hand, it is advantageous from a thermal viewpoint to make the distance between the cavity and the gas discharge lamp as large as possible. 25 In practice, the distance must be chosen optimally.

The light-generating means control means for operating a gas discharge lamp are preferably included in the cavity. This offers the advantage that good coordination between the gas discharge lamp and the light generating means is already made in advance. This guarantees greater electrical safety and optimum efficiency.

Preferably, the light generating means comprises electronic light generating means. Electronic light-generating control means have an even greater efficiency than conventional light-generating control means, which comprise, for example, a ballast and an ignition device. The higher efficiency of electronic light-generating control means ensures that with the same light output less heat is generated by the light source and by the light-generating control means. On the other hand, with constant heat development, a higher light output is possible.

The cooling capacity of the part of the housing at the location of the cavity is advantageously greater than that of the other parts of the housing. As a result of this measure, the light-generating means control means can be cooled even better. For a safe and efficient operation of the light-generating means, the temperature of the light-generating means must also remain below a certain value. Especially in closed housings, the cooling capacity must be adjusted to this value. Therefore, the possibility of heat dissipation (the cooling capacity) should be greatest with the sensitive (electronic) light generating control means.

In a special embodiment, the cooling surface of the cooling fins per unit length, as seen in the longitudinal direction of the light source housing, at the location of the cavity is larger than that of the possible cooling ribs on the other parts of the housing. Thus, it is expediently achieved that the cooling capacity is greater on site than on the other parts of the housing. Said measure can easily be realized by providing larger cooling ribs or a greater density of cooling ribs.

In a particularly attractive embodiment, the outer circumference of all cooling fins is substantially the same. By the outer circumference of the cooling fins is meant the largest circumference of a cross-section through the cooling fins, seen parallel to the longitudinal axis of the light source housing. Such an embodiment has a uniform outer circumference over, in principle, the entire length of the housing, so that the maximum cross-section can remain limited and constant. Aesthetically, in many cases this is preferable to different dimensions of the cooling fins. Thus, for example, the density of cooling ribs at the location of the cavity should be greater than elsewhere on the housing. However, the individual cooling ribs preferably have a larger cooling surface at the location of the cavity than the possible cooling ribs on the other parts of the housing. With the same outer circumference, this means that the inner dimensions of the housing at the location of the cavity must be correspondingly smaller than in the other parts of the housing. This has the further advantage that the cross-sectional area of the heat-conducting housing itself, i.e. without cooling fins, is smaller at the cavity than elsewhere in the housing. This further limits the heat supply to the cavity.

The cooling fins can form part of the housing, or can also form separate parts. In the latter case, the cooling fins 10 are connected to the housing for example with screws, thermal glue or the like. The cooling fins are usually made of a good heat-conducting material, for example a metal. Other materials, such as graphite, are also suitable. In addition, the surface of the cooling fins can be arranged for improved heat dissipation. To that end, for example, the surface of the cooling fins comprises dark-colored paint, or, for example, grooves and other surface roughnesses to further increase the heat-emitting surface.

The cooling ribs preferably run in a substantially vertical plane. The vertical direction is thereby determined by the direction of gravity. In this way, optimum cooling is ensured by the air flowing along the cooling fins.

If the light source housing and the cooling ribs form a whole, and are for instance made of metal in a casting process, it is advantageous if thin parts, including cooling ribs, are short and / or slightly tapered. This improves the release from the mold. Despite this production-technical difficulty, it is nevertheless preferable to increase the surface area of the cooling fins at the cavity. The surface change of the cooling fins in the direction of the cavity can be sudden but also gradual. For example, the effective inner diameter of the housing decreases toward the cavity. The effective inner diameter of the housing can also change stepwise at the level of the transition from the cavity to the other parts of the light source housing.

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The housing is advantageously thermally connected via the heat-conducting means to substantially the entire outer surface of a reflector surrounding the working light-generating means. In this way as much heat as possible is already dissipated as close as possible to the source to the housing, and in particular to the cooling fins on the housing. As a result, the supply in the direction of the cavity, and in particular in the direction of the light-generating means control means, is further limited. The reflector can herein form a part of the housing.

It is also possible to combine the gas discharge lamp with a reflector. Although an optimum alignment of the gas discharge lamp with respect to the reflector can hereby be ensured, such light-generating means are usually much larger.

Preferably, the reflector is a dichroic reflector. In particular, this reflector reflects the visible light falling on it, while infrared heat radiation is essentially transmitted and / or absorbed. As a result, the radiation emitted by the light-generating means becomes relatively infra-red, while the heat and the radiation can be efficiently dissipated via the heat-conducting means thermally connected to the reflector.

In an attractive embodiment the space between the heat-conducting means and the reflector surrounding the working light-generating means is substantially filled with a deformable heat-conducting mass. An even better thermal contact is thus guaranteed between the heat conducting means and the reflector. In addition, differences in expansion between the reflector and the heat-conducting means can be absorbed by the deformation of the heat-conducting mass. The heat-conducting mass is advantageously a paste, such as heat-conducting silicone paste, but the invention is not limited thereto.

Preferably, the deformable heat-conducting mass absorbs infrared radiation. Thus, the infrared radiation is prevented from reflecting on the heat-conducting mass and in this way the reflector 35 again passes and is emitted. For example, it is possible to use a heat-conducting mass comprising graphite, carbon black or another substance absorbing infrared radiation. Other surfaces in the housing, in particular that of the heat-conducting means, are preferably also provided with infrared radiation-absorbing means, for example black lacquer or paint. Thus, it is further prevented that infrared radiation reflects and the reflector passes.

In an attractive embodiment of the light source housing, it is substantially splash-proof. Because the light source housing according to the invention is not dependent on cooling with air, it is suitable for being made substantially splash-proof. Thus, the light source housing can be used in many places, for example in the open air, or in other places where the housing can be exposed to water or other drop-shaped substances.

Advantageously, the diameter of the light source housing 15 perpendicular to the longitudinal axis thereof is a maximum of 150 mm. More advantageously, the diameter of the light source housing perpendicular to the longitudinal axis thereof is a maximum of 100 mm. The light source housing, including the cooling fins, can herein have a substantially cylindrical shape. The light source housing, or a part thereof, such as for example the cooling fins, could also have a different shape, for example block-shaped. In that case diameter means the length of the longest side. With the light source housing according to the invention it is possible for the first time to form such compact gas discharge light sources, in particular but not only suitable for use outdoors or in other less favorable conditions. Naturally, indoor use is also possible.

Further provided is a light generating assembly comprising a light source housing according to the invention and a gas discharge lamp. A compact light source can thus be obtained. The choice of the gas discharge lamp is not particularly limited.

For example, a so-called compact fluorescent lamp (PL) could be used. The gas discharge lamp is preferably selected from a high-pressure mercury vapor lamp or a metal halide lamp. A simple and compact construction is possible with these light-generating means. However, other gas discharge lamps known in the prior art can also be used in the light-generating assembly according to the invention.

The invention will be explained in more detail below with reference to the accompanying drawing. In the drawing: Fig. 1 shows partially cut away and in perspective a lighting device according to the invention; Fig. 2 shows an example of a lamp body in cross section and in perspective; Fig. 3 is a perspective view of a cap portion 16 for a beam angle 10 of 90 °; Fig. 4 is a cross-sectional view of a lighting device according to the invention, comprising a light generating assembly with light source housing according to the invention and a light pipe; and Fig. 5 shows another cross-sectional view of an embodiment of the light source housing according to the invention.

Fig. 1 shows a partial cut-away and a perspective view of a light source 1 and a carrier part 2.

The light source comprises a light source housing 3, here in two assembled parts. The light source housing 3 comprises a cavity 4 for light generating means 6 as well as a cavity 5 for light generating means control means (not shown). 7 indicates a connection opening, 8 indicates fastener eyes and 8a a light source fastener. 9 is a lamp cap as a connection between cavity 4 and cavity 5.

The carrier part 2 comprises a profile body with first grooves 10, second grooves 11 and in one of the second grooves 11 a supply cable 12. Furthermore, the carrier part 2 comprises on its outside suspension grooves 13 for back or side mounting, and a cap mounting groove 14.

The possible light source 1 to be used will be further elucidated in the following figures. It is noted here that the light source 1 can be slidable in the lamp relative to the carrier portion 2. To that end, a schematically illustrated light source attachment means, e.g. a spreader pin, can be connected via fastener eye 8 in a first groove 10 of the carrier portion} 0 λ. .. - ·: <- 17 - are stung. The light source 1 can thus be fixed at the desired location.

The light generating means control means (not shown) in cavity 5 can be connected to supply cable 12, which is located in a second groove 11. To this end, the light-generating control means comprise, for example, connection pins which can be brought through connection opening 7 to the electrical conductors of the supply cable 12. If desired, the connecting pins must penetrate the insulation of the supply cable for this purpose. This manner of fixing, through the connection opening 7, at the same time results in a good shielding of the electrical connection.

Although the cap portion of the lamp body of the lamp according to the invention is not shown in Fig. 1, it can be formed over the light source 2, or the cap portion can connect to the light source 2 on the left and / or right.

The lamp cap 9 is, for example, a ceramic lamp cap, which enables good electrical and heat insulation between the part where the light is generated and the part where the power supply enters the light source or the control is located. It is important that the lamp cap forms a separation between the two cavities 4 and 5, such that no connecting wires need to be present in the cavity 4.

FIG. 2 shows an example of a lamp body in cross-section and in perspective. The same reference numbers indicate the same parts everywhere.

A reflection film is indicated by 15.

Cap portion 16 is provided with prism foil 17 on the inside, and is attached with cap protrusions 18 in cap mounting grooves 14. The grooves 14 comprise a deeper portion 19 and a higher portion 20.

In the figure, supply cable 12, located in a second groove 11, and also the rest of the inner surface of the carrier part 2, are covered with a reflection foil 15. In this connection, the term foil must be interpreted broadly and can be a flexible or rigid thin or thick film, consisting of or provided with reflective material, for example titanium dioxide or magnesium oxide powder, reflective paint, etc. The reflective film 15 may be made, for example, by laminating a reflective film on a supporting film. The reflection foil 15 can also be, for example, preformed into a profile part or molded part that is itself form-retaining.

If the reflection foil 15 does not have its own shape, for example is a thin flexible foil, it can easily be used to coat the inside of the carrier portion 2. If desired, for example in order to obtain a different radiating angle of the reflector, a different shape than the usual semicircle can be provided to the reflection foil 15. For example, a parabola can be provided, which, incidentally, also by means of own protrusions or the like in first grooves 10 can be confirmed. Of course, other methods of attachment, such as sticking, can also be used.

In addition to a different beam angle, a different beam direction can be chosen for the lamp than straight to the front, for example diagonally to the left or right. To that end, for example, the reflection foil can be arranged in the carrier part at the relevant angle, for instance by arranging the fixing means in the relevant angle thereto and subsequently arranging the reflection foil 15 in the correct first grooves 10.

Cap portion 16 in the figure comprises substantially half a tube. It can be made from a variety of materials, preferably crystal-clear material, including polycarbonate, but preferably a suitable bio-resin, because when used outdoors it is very resistant to aging, yellowing, scratching, etc. Bio-resins are in particular resins, or generally: polymers, based on organic raw materials, and therefore not on petroleum basis. In addition to crystal-clear materials, it is of course also possible to use colored materials, or for example milky materials, to achieve certain light effects.

The cap portion 16 is mounted in carrier portion 2 with the aid of cap protrusions 18. These are pressed into cap attachment grooves 14. Grooves 14 and protrusions 18 together form cap attachment means. These cap fastening means are of anti-loosening design in the figure. A water-repellent gel or the like may preferably be provided in the deeper portion 19 of the cap attachment groove 14. This can then be pressed by the cap protrusion 18 and thus form a water-repellent seal between cap part 16 and carrier part 2.

Moreover, at the top of the hood attachment groove 14, in particular in the higher portion 20, a lace, strip or the like (not shown) can be provided, preferably under pressure, to exert additional connection pressure 10 on the combination of hood portion 16 and carrier portion 2. Thus, provides an even more reliable watertight connection of cap portion 16 to carrier portion 2. However, hardly any protruding parts are present. Said lace, strip or the like can simply be pulled loose in order to be able to easily remove the associated hood portion 16 from the hood portion 2.

For the purpose of sealing, one of the cap fastening means 14, 18 may comprise a soft material which can be yielded or compressed to some extent. For example and preferably a portion of the cap protrusion 18 is made of said soft material. If desired, this soft material can be co-extruded with an associated part of hard material, if the latter material is desired for, for example, the profile part with the reflection film 15, or the carrier part 2, the soft material can also be a part of the reflection film 15, for example a portion that is folded around the edge of the carrier portion 2, and pressed together with the cap protrusion 18 into the cap attachment groove 14.

Fig. 3 shows in perspective a cap portion 16 for a beam angle of 90 °.

Hood protrusion 18 is provided here with a bulge 21. A prism film 15 here consists of three parallel strips between retaining cams 22.

The thickening 21 fulfills the function mentioned in the discussion of Figure 2 35 of more reliable clamping of the cap portion 16 in the cap retaining groove 14. Advantageously, the thickening comprises 21 - 20 - softer material than the rest of the cap protrusion 18, for the more reliable seal.

In the figure, the reflection foil 15 is made up of three parallel strips of prism foil, for example OLF foil from the manufacturer 3M. The three parallel strips provide a beam angle, i.e., an enclosed angle of the light emitting portion, of 90 °, but this can be easily increased or decreased by adding or removing strips, or by changing the distance between the retaining cams 22. For example, with six parallel strips, the beam angle is 180 °.

A reflection foil 15 in the form of, for example, OLF film is relatively rigid in itself. Moreover, the textured surface is on the outside of the film, so fixing by means of gluing is very problematic. Heretofore, the film was confirmed by forming the film into a complete tube. However, by applying the film in the form of strips, one is much more variable in the design of lamps.

The retaining cams 22 used for mounting are, for example, ridges or aligned cams with, for example, a mushroom-shaped profile. The strips of foil can then be clicked or slid in between or the like. The strips of foil can then easily be shifted and / or exchanged.

Up to now there has been talk of light sources in a housing that preferably emit bundled light. However, it is also possible to provide several LEDs as light generating means. For example, LEDs can be cast in a transparent plastic holder that can be mounted in the carrier portion in the same manner as a light source 1 can be mounted. Connection wires for connecting the LEDs to the power supply cable can then come from each holder with one or more LEDs. The connection can be made in a variety of ways, for example with the aid of crown stones, weld connections, pointed connection pins etc.

FIG. 4 is a sectional view of a light generating means assembly 31 which connects to a lamp body 42.

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The light generating assembly 31 can serve as a light source in the lamp according to the invention, which lamp is then formed as the combination in FIG. 4, coupled with other such combinations.

The light generating assembly comprises a light source housing 32.

Circular cooling ribs 33 emanate from the light source housing 32. In the light source housing 32 there is a cavity 34 in which light generating means 35 are arranged. The light-generating control means 35 are connected via a wire 36 to an energy source, read with the power supply cable 12 of the lamp, which, however, is not drawn through the lamp body for the sake of clarity, and via light-generating means connection means 37 in connection with a gas discharge lamp 38.

The gas discharge lamp 38 is an example of another light generating means that can be used. The gas discharge lamp 38 is arranged in a reflector 40 by means of light generating means 39. The reflector 40 is sealed with a glass plate 41.

A light pipe 42 connects to the light generator assembly 31. The light pipe 42 comprises a transparent tube 43 which is provided on the inside with light scattering means 44. The light pipe 42 is mounted on the light generating means assembly 31 by means of a slidable ring 45.

In the embodiment shown, the light source housing 32 combines the functions of casing and heat conducting means. In principle, the light source housing 32 consists of a piece of heat-conducting material. A metal such as aluminum or copper is usually used for this, but in theory a plastic is also possible with a high content of fillers that increase the thermal conductivity. However, metals are preferred because of their higher melting temperature.

Cooling ribs 33 are located on the outside of the light source housing 32. Near the gas discharge lamp 38, the cooling ribs 33 often have a relatively small cooling surface. The heat dissipation means which in this embodiment form an integral part of the light source housing 32 have a large cross-sectional area, and can therefore dissipate heat simply and efficiently to the cooling ribs 33. At the cavity 34, the cooling ribs 33 have a (- 22 - much larger) cooling surface, whereby at the same time the light source housing 32 has been given a correspondingly smaller diameter, the heat-conducting cross-sectional area of the light source housing 32 at the level of the cavity 34 is hereby smaller.

By this is meant that the surface of the material of the heat-conducting housing is smaller in a cross-section at the height of the cavity than in a cross-section elsewhere on the housing. As a result, less heat is supplied in the direction of the cavity 34. Because at the same time the cooling capacity of the cooling ribs 33 is greater at the level of the cavity 34, the temperature of the light-generating means control means 35 accommodated in the cavity 34 can remain effectively low.

The light generating means 35 can for instance be arranged in the cavity 34 via an opening at the rear of the light source housing 32. The light source housing 32 can also be composed of two or more parts to be assembled. In this way the light generator assembly can easily be repaired or adapted to other wishes.

The light-generating means control means 35 in this case 20 comprise an electronic ballast. The more conventional combinations of a ballast and an ignition device could also be used. Preferably, the light-generating means connection means 37 and the light-generating means fixing means 39 must be able to withstand the often high ignition voltages, for example 4.5 kV. The light-generating means connecting means 37 for this purpose are usually double or, for example, Teflon®-insulated electric wires and the light-generating means fixing means 39 are often partly ceramic lamp bases.

Incidentally, in this description of the figures it is assumed that there is a light generating means control means in the cavity 34 in the form of, for example, a ballast. However, this can be changed to a power supply for LEDs or other light generating means, or a control unit therefor. They can also produce a lot of heat.

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The gas discharge lamp 38 is a high-pressure mercury vapor lamp. If desired, it can be provided with one or more additives to increase the light output. The power is freely selectable within the maximum prescribed by the heat dissipation capacity of the light generator assembly 31. For example, the power of the gas discharge lamp 8 is approximately 100 watts. In practice, other types of light generating means are also suitable, such as sulfur vapor lamps. In these light-generating means, the light-generating means are often microwave sources.

The gas discharge lamp 38 is arranged in a reflector 40. The shape of the reflector 40 is appropriately chosen. For example, the reflector 40 is a paraboloid and the gas discharge lamp 38 is arranged so that the center of the arc discharge is at the focal point of the paraboloid. In this way a parallel light beam is obtained. If desired, other arrangements of the gas discharge lamp 8 in the reflector 40 are also possible, for example slightly from the focal point in order to obtain a converging or diverging light beam. Moreover, other efficient forms of the reflector 40 are also possible, for example a facet reflector.

In the shown embodiment of the light-generating device assembly according to the invention, the reflector is sealed with a transparent plate 41. Preferably, the light-generating device assembly 31 is water-tightly sealed. The material 25 of the transparent plate 41 is not particularly limited. This can be selected from glass, quartz, other transparent minerals, high-temperature resistant plastics, etc. It is also possible to take a grid, for example from metal. If desired, the transparent plate 41 can be provided with optical elements, for example lenses, prisms, etc. It is also possible to choose a material for the transparent plate 41 which absorbs a part of the light from the gas discharge lamp 38. Certain color effects can thus be achieved.

The light pipe 42 comprises a tube 43 of a transparent plastic. On the inside, this tube 43 is provided with light-scattering means 44. Preferably, these light-scattering means 44 comprise a series of prisms, for example in the form of an Optical Lighting Film from the company 3M. In this way a uniform appearance can be obtained through the light pipe. Other light scattering agents are also possible. For example, 5 grooves, pyramids, etc., depending on the desired light properties.

The light pipe 42 is attached to the light-generating device 31 by means of a slidable ring 45. In this simple manner, the light-generating device 31 of the lighting device shown can be changed, cleaned, repaired, etc.

The light pipe 41 is, for example, essentially a cylinder with a diameter of at most 150 mm or even of at most 100 mm. The light-generating assembly 31 preferably has cross-sectional dimensions 15 corresponding to those of the light pipe 42.

Fig. 5 shows another embodiment of the light source housing according to the invention. Some components have been omitted for the sake of clarity, such as the light generating means and the gas discharge lamp.

In this case, the light source housing comprises a housing 46 enclosing a cavity 34. At the level of the cavity 34 the housing 46 comprises large cooling ribs 47, and elsewhere smaller cooling ribs 48. On the other side of the housing 46 a reflector 40 is included which is enclosed on the outside by heat conducting means 49 and closed on the other side by the transparent plate 41.

Between the reflector 40 and the heat-conducting means 49, and between the heat-conducting means 49 and the housing 46, there is a deformable heat-conducting mass 50, in the form of a silicone paste with a soot filling, so that infrared radiation 30 is well absorbed.

Large cooling ribs 47 are located at the level of the enclosed cavity 34. These can be separate elements, for example metal rings. These do not have to be part of the housing 46, but can also be provided by means of welding, (hard) soldering, gluing with a heat-conducting glue, etc. Similarly, the cooling ribs 48 with a smaller surface area can are provided.

- / - 25 -

The cooling ribs 47 and 48 are preferably not circumferential cooling ribs, but each consist of two half-rings. In this way the housing 46 remains easily divisible, for receiving or exchanging light generating means (not shown) or a gas discharge lamp (not shown). The cooling ribs may otherwise also have a different shape, for example oval or square for maximum cooling surface.

The heat-conducting means 49 also preferably comprise two or more parts, as a result of which easy access can also be obtained to the space in which the gas discharge lamp can be arranged. The heat conducting means 49 must have a good thermal connection to both the reflector 40 and the housing 46, advantageously to enable good heat dissipation. To this end, there is a heat-conducting mass 40, for example a soft silicone paste, between the heat-conducting means and either the reflector 40 or the housing 46. This can also accommodate expansion differences and must therefore be of the permanently deformable, non-drying type.

In the exemplary embodiment shown there are two types of cooling fins, small cooling ribs 48 and large cooling ribs 47. It is also possible to give the housing 46 a gradually narrowing inside diameter, the cooling ribs on the outside, with the outside circumference remaining the same, have a gradually increasing cooling surface in the direction of the cavity 34. In addition, it is optically attractive to keep the outer circumference of the cooling fins constant over the length of the light source housing. However, it is of course also possible to vary the outer circumference of the cooling fins, depending on the desired cooling capacity of the cooling fins.

The exemplary embodiment shown in Figs. 4 and 5 describes a lamp in which lamp body and light source have substantially the same diameter. Such lamps have a different, less regular brightness distribution than other described shapes. These could be made more homogeneous by a diffuse outer cover, or other measures.

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Claims (16)

A lamp, comprising an elongated hollow lamp body with a light-emitting surface provided with light-distributing means (15), and a light source (1) connected to the lamp body, characterized in that the lamp also comprises a supply cable (12) which extends therethrough substantially in a longitudinal direction of the lamp body (2, 16), and that a plurality of light sources (1) are present, each of which is electrically connected to the power supply cable (12) and at least one of which is mounted in the lamp body (2) , 16). 10 Lamp according to claim 1, characterized in that the supply cable is received in a recess in the lamp body (2). 3. A lamp according to any one of the preceding claims, characterized in that the supply cable (12) comprises conductors which are provided with insulation, and that the light sources (1) are provided with connecting pins adapted to pierce through the insulation in order to thus making electrical contact with the current conductors. A lamp according to any one of the preceding claims, characterized in that the light sources (1) are provided with first fixing means (8, 8a) and that the lamp body is provided with second fixing means which cooperate with the first fixing means (8, 8a). 25 5. A lamp according to claim 4, characterized in that the second fastening means comprise a recess (10) extending in the longitudinal direction of the lamp body (2) and that the first fastening means can be displaced in the second fastening means and can be fixed therein. 6. A lamp according to any one of the preceding claims, characterized in that the light distribution means comprise a diffuser. J02u3.7 - 27 - A lamp according to any one of the preceding claims, characterized in that the light-distributing means comprise a prism film (15). A lamp according to claim 7, characterized in that the prism foil 5 (15) comprises at least two mutually parallel strips, which are releasably arranged in the lamp body (21) with the aid of retaining means (22). 9. A lamp according to any one of the preceding claims, characterized in that the lamp body comprises a support part (2) as well as an at least partially light-transmitting hood part (16), wherein the support part (2) and the hood part (16) are detachably attached to each other with the aid of hood fasteners (14, 18). A lamp as claimed in claim 9, characterized in that the hood mounting means comprises a protrusion (18) extending in the longitudinal direction of the hood component and cooperating with a groove (14) in the support component (2). A lamp according to claim 9 or 10, characterized in that the cap component (16) comprises at least two sub-caps that can be detached from the carrier component (2) independently of each other. 12. A lamp according to any one of claims 9-11, characterized in that the support part (2) comprises a reflector (15). A lamp according to claim 12, characterized in that the reflector comprises a foil (15) which at least partially covers the recess (11) and the supply cable (12) located therein. 30 A lamp according to any one of the preceding claims, characterized in that it comprises light sources that emit light in substantially a longitudinal direction of the lamp body (2, 16). A lamp according to any one of the preceding claims, characterized in that the light sources (1) comprise an LED. - 28 - 16. A lamp according to any one of the preceding claims, characterized in that the light sources (1) comprise a light source housing, which comprises a heat-conducting housing provided with cooling fins for receiving a light-generating means and a cavity enclosed by the heat-conducting housing for accommodating light generator control means. ; ü v JÖ / ƒ