EP3794276B1 - Led lighting module and method for producing same - Google Patents

Description

Description: TECHNICAL AREA

The present invention relates to the technical field of light generation using light-emitting diodes (LED); LEDs denotes a number of such diodes.

A lamp module is the light-generating lighting device or the light-generating illuminant of a lamp or lamp. The lighting module according to the invention is preferably intended for outdoor use and can be provided here in particular in lights for illuminating streets, paths and squares according to DIN EN 13201. For this purpose, the LED lamp module according to the invention can be attached as a light source to a corresponding predetermined street lamp.

Furthermore, the present invention specifies a method for producing such an LED lamp module.

STATE OF THE ART

• das besteht aus einem Gehäuseteil und einer transparenten Abdeckplatte,
• wobei je am Gehäuseteil und/oder an der Abdeckplatte einstückig eine umlaufende Seitenwand so angeformt ist, dass das Gehäuseteil, die eine Seitenwand oder beide
• Seitenwände und die Abdeckplatte gemeinsam einen hermetisch dichten Gehäuseinnenraum begrenzen,
• in dem sich eine Platine befindet, auf der eine Anzahl je beabstandet zueinander angeordnete LEDs sitzen,
• wobei jeder einzelnen LED je ein Sekundäroptikelement zugeordnet ist, welches das von einer gegebenen LED erzeugte LED-Licht einfängt und entsprechend einem vorgegebenen Beleuchtungszweck richtet und bündelt.

More specifically, the present invention relates to an LED lamp module with a two-part module housing,

• which consists of a housing part and a transparent cover plate,
• wherein a peripheral side wall is integrally formed on the housing part and/or on the cover plate in such a way that the housing part, one side wall or both
• Side walls and the cover plate together delimit a hermetically sealed housing interior,
• in which there is a circuit board on which a number of spaced-apart LEDs are located,
• with each individual LED being associated with a secondary optical element which captures the LED light generated by a given LED and directs and focuses it in accordance with a predetermined lighting purpose.

An LED lamp module of this kind is in the document WO 2016/094038 A1 described. This document relates to an outdoor LED light with a plastic housing provided with an outer frame. The plastic housing has two main parts, namely an upper housing part and a cover plate. The upper housing part consists of a flat plate, on the periphery of which a peripheral side wall is integrally attached. In some embodiments, a peripheral side wall may or may not also be formed on the perimeter of the cover plate, which is flush with the side wall on the housing part. These two plastic parts can be bonded together using standard means of joining plastic parts, such as hot staking, vibration welding, ultrasonic welding, gluing, and the like, to create a weatherproof module housing. The plastic housing can be made of polycarbonate (PC), polymethyl methacrylate (PMMA), glass or a combination of these materials. In the module housing there is a circuit board on which an LED or several LEDs are attached. A secondary optical element, which is also referred to as a lens, is assigned to each of these LEDs. Such optical lenses may be fixed to the circuit board, or a number of such optical lenses may be assembled into a matrix formed on a planar optical board. Such an optical panel may be made of polymethyl methacrylate (PMMA), polycarbonate (PC) and/or the like and may be attached to the module body, possibly with the aid of gasket material to create a seal around the optical panel. The LED light module described here is provided with a mechanically stable metal frame with which the two-piece plastic housing is attached to a mast, post or the like.

• die Metall-Gehäuseplatte aus einem, für Gehäuse geeigneten Leichtmetall oder aus einer Zamak-Legierung besteht;
• die Abdeckplatte aus einem weitgehend UV-undurchlässigen oder UV-undurchlässigen PMMA-Material oder aus einem UV-stabilisierten PC-Material besteht;
• jedes Sekundäroptikelement ein Lichtleitelement oder ein alternatives Lichtleitelement aufweist, das aus dem Abdeckplattenmaterial besteht und das an der Abdeckplatte einstückig angeformt ist; und
• zwischen Metall-Gehäuseplatte und Abdeckplatte eine hermetisch dichte Verbindung ausgebildet ist.

The document KR 2014 0076390 A relates to an LED fish lamp. This is understood to mean a lamp equipped with a large number of LEDs, which is used under water to attract fish; Because of the use under water, this LED fish lamp must be watertight. The words and terms of the present application essentially disclose:
An LED light module with a two-part module housing, which consists of a metal housing plate and a transparent cover plate, with a peripheral side wall being integrally formed on the metal housing plate and/or on the cover plate, so that the metal housing plate, the one Side wall or both side walls and the cover plate together define a hermetically sealed housing interior, in which there is a circuit board on which a number of spaced-apart LEDs sit; andeach individual LED is associated with a secondary optical element which captures the LED light generated by a given LED and directs and focuses it in accordance with a predetermined lighting purpose, wherein

• the metal housing plate consists of a light metal suitable for housings or of a zamak alloy;
• the cover plate consists of a largely UV-impermeable or UV-impermeable PMMA material or of a UV-stabilized PC material;
• each secondary optic element comprises a light guide element or an alternative light guide element which consists of the cover plate material and which is integrally formed on the cover plate; and
• a hermetically sealed connection is formed between the metal housing plate and the cover plate.

In the known LED fish lamp, the LEDs are arranged on the circuit board in several parallel rows spaced apart from one another, and the light guide elements are elongated bead-like thickenings on the outside of the cover plate, with each LED row being assigned such a thickening arranged in alignment is. The hermetically sealed connection consists of two rubber rings, with each sealing ring inserted in a groove that is recessed in opposite surfaces in the edge area of the metal housing plate and cover plate.

• Ein flaches, quaderförmiges, hermetisch dichtes Gehäuse, das einen Gehäuseinnenraum begrenzt und das besteht aus
  • -- einer, im Wesentlichen rechteckigen Bodenplatte aus Aluminium (AI) oder einer Al-Legierung;
  • -- einem einstückigen, geschlossenen, die Gehäuseseitenwände bildenden Rahmen, der zwei voneinander beabstandete Rahmenstirnflächen hat, und der auf der Bodenplatte sitzt und im Wesentlichen mit deren Außenumfang fluchtet; und
  • -- einer, auf dem Rahmen aufliegenden, aus einem transparenten Kunststoff bestehenden Deckenplatte, die im Wesentlichen mit dem Außenumfang des Rahmens fluchtet; wobei
  • -- die eine Rahmenstirnfläche hermetisch dicht mit der Deckenplatte verbunden ist, und die andere Rahmenstirnfläche hermetisch dicht mit der Bodenplatte verbunden ist; und mit
• mehreren, im Gehäuseinnenraum befindlichen LEDs und mit einer, diesen LEDs zugeordneten Sekundäroptik, welche das von den LEDs über einen recht großen Raumwinkelbereich abgestrahlte Licht zu einem begrenzten bandförmigen Lichtstrom richtet und bündelt; und mit
• einer im Gehäuseinnenraum befindlichen Platine mit elektrischen und/oder elektronischen, mit Betriebsstrom, Signalspannungen und gegebenenfalls weiteren Signalen versorgbaren Bauelementen zur Versorgung, Steuerung und Kontrolle der LEDs; wobei
• in diesem Gehäuseinnenraum eine argonhaltige Atmosphäre vorgesehen ist. Entsprechend dem einzigen Ausführungsbeispiel wird der Rahmen aus vier quaderförmigen Seitenwänden zusammengeklebt, die teilweise oder vollständig hohl sind, und in den so gebildeten Hohlräumen soll pulverförmiges Trocknungsmittel, wie etwa Zeolith und/oder Silicagel, untergebracht sein. Das hermetisch dichte Verbinden der einen Rahmenstirnfläche mit der Bodenplatte und der anderen Rahmenstirnfläche mit der Deckenplatte soll durch Kleben erfolgen. Als Klebstoff wird insbesondere ein dauerelastischer, UV-beständiger sowie wasser- und wasserdampf-undurchlässiger Butylkleber, hier insbesondere Isobutylen, empfohlen. Ferner soll der Rahmen von einer elastischen Abdeckung eingehüllt sein, die aus Silikon, Polyurethan und/oder Polysulfid bestehen kann und ebenfalls mit der Bodenplatte sowie mit der Deckenplatte verklebt sein soll.

The document DE 10 2008 058 757 A1 relates to an LED light module, which is referred to there as a lighting device and which essentially has:

• A flat, cuboid, hermetically sealed housing that delimits a housing interior and consists of
  • -- a substantially rectangular bottom plate made of aluminum (Al) or an Al alloy;
  • -- a one-piece, closed frame forming the housing side walls, having two spaced-apart frame faces, and which sits on the bottom plate and is substantially flush with the outer periphery thereof; and
  • -- a cover plate resting on the frame, consisting of a transparent plastic and essentially flush with the outer circumference of the frame; whereby
  • -- a frame face is hermetically connected to the top panel, and the other frame face is hermetically connected to the bottom panel; and with
• a plurality of LEDs located in the interior of the housing and with secondary optics assigned to these LEDs, which directs and bundles the light emitted by the LEDs over a fairly large solid angle range into a limited linear luminous flux; and with
• a circuit board located in the interior of the housing with electrical and/or electronic components that can be supplied with operating current, signal voltages and optionally other signals for the supply, control and monitoring of the LEDs; whereby
• an argon-containing atmosphere is provided in this housing interior. According to the only embodiment, the frame is glued together from four parallelepiped-shaped side walls, which are partially or completely hollow, and in the cavities so formed it is intended to house powdered desiccant, such as zeolite and/or silica gel. The hermetically sealed connection of one end face of the frame to the base plate and the other end face of the frame to the top plate should be done by gluing. As an adhesive, in particular Permanently elastic, UV-resistant and impermeable to water and water vapor butyl adhesive, especially isobutylene, is recommended. Furthermore, the frame should be encased by an elastic cover, which can consist of silicone, polyurethane and/or polysulfide and should also be glued to the floor panel and to the ceiling panel.

The document EP 2 776 883 B1 discloses a street lamp equipped with LEDs as a light source. Each LED is assigned a light guide element made of transparent material, which modifies the light distribution pattern of the light beams generated by an LED. The street lamp is arranged at a given height "H" above the road surface, and such a light distribution pattern is aimed at that a street lamp can uniformly illuminate a road surface whose length is about 4.5 times the height "H" and whose Width corresponds to about half the height "H".

The unpublished German patent DE 10 2017 000 571 B3 relates to an LED lamp module and a method for its production.

• ein flaches, quaderförmiges, hermetisch dichtes Modulgehäuse, das
  einen Gehäuseinnenraum begrenzt und das besteht aus drei Bestandteilen, nämlich
  • -- einer, im Wesentlichen rechteckigen Bodenplatte aus Aluminium (Al) oder einer Al-Legierung;
  • -- einem einstückigen, geschlossenen, die Gehäuseseitenwände bildenden Rahmen, der zwei voneinander beabstandete Rahmenstirnflächen hat und der auf der Bodenplatte sitzt und im Wesentlichen mit deren Außenumfang fluchtet;
  • -- einer, auf dem Rahmen aufliegenden, aus einem transparenten Kunststoff bestehenden Deckenplatte, die im Wesentlichen mit dem Außenumfang des Rahmens fluchtet; wobei
  • -- die eine Rahmenstirnfläche hermetisch dicht mit der Deckenplatte verbunden ist, und die andere Rahmenstirnfläche hermetisch dicht mit der Bodenplatte verbunden ist; und mit
• mehreren, im Gehäuseinnenraum befindlichen Licht emittierenden Dioden (LEDs von light emitting diodes) und mit einer, diesen LEDs oder LED-Gruppen zugeordneten Sekundäroptik, welche das von den LEDs über einen weiten Raumwinkelbereich abgestrahlte Licht zu einem begrenzten, bandförmigen Lichtstrom richtet und bündelt; und mit
• einer im Gehäuseinnenraum befindlichen Platine mit elektrischen und/oder elektronischen, mit Betriebsstrom, Signalspannungen und gegebenenfalls weiteren Signalen versorgbaren Bauelementen zur Versorgung, Steuerung und Kontrolle der LEDs; und
• in diesem Gehäuseinnenraum eine argonhaltige Atmosphäre herrscht.

This LED light module has

• a flat, cuboid, hermetically sealed module housing that
  delimits a housing interior and that consists of three components, viz
  • -- a substantially rectangular bottom plate made of aluminum (Al) or an Al alloy;
  • -- a one-piece, closed frame forming the housing side walls, which frame has two spaced-apart frame faces and which sits on the bottom plate and is substantially flush with the outer periphery thereof;
  • -- a cover plate resting on the frame, consisting of a transparent plastic and essentially flush with the outer circumference of the frame; whereby
  • -- a frame face is hermetically sealed to the ceiling panel, and the other frame face is hermetically sealed the bottom plate is connected; and with
• several light-emitting diodes (LEDs of light emitting diodes ) located in the interior of the housing and with secondary optics assigned to these LEDs or LED groups, which directs the light emitted by the LEDs over a wide solid angle range to a limited, linear luminous flux and bundles and with
• a circuit board located in the interior of the housing with electrical and/or electronic components that can be supplied with operating current, signal voltages and optionally other signals for the supply, control and monitoring of the LEDs; and
• an argon-containing atmosphere prevails in this housing interior.

• die Deckenplatte aus einem weitgehend UV-undurchlässigen oder aus einem UV-undurchlässigem PMMA-Material besteht, und an einer Hauptfläche der Deckenplatte in deren Randbereich eine umlaufende Nut ausgespart ist;
• der Rahmen aus einem PMMA-Material besteht, und an der einen Rahmenstirnfläche ein umlaufender Steg einstückig angeformt ist, der in Richtung der Rahmenhöhe von der Rahmenstirnfläche absteht;
• diese Rahmenstirnfläche mittels Ultraschallverschweißung mit der Deckenplatte verbunden ist; und
• das Modulgehäuse eine Langzeitdichtigkeit aufweist, die gewährleistet, dass nach Durchführung einer 46 Wochen dauernden beschleunigten Alterungsbehandlung, während der das Modulgehäuse stets bei etwa 50 °C sowie pro Tag eine Std. lang unter Umgebungsluftdruck sowie 23 Std. lang unter einem, gegenüber dem Umgebungsluftdruck um 100 mbar verminderten Luftdruck gehalten wird, die Atmosphäre im Gehäuseinnenraum des Modulgehäuses immer noch zu wenigstens 30 Vol.-% aus Argon aus der ursprünglich eingebrachten 100 %-igen Ar-Befüllung besteht.

The inventive feature of this LED lighting module is that

• the cover panel consists of a largely UV-impermeable or UV-impermeable PMMA material, and a peripheral groove is cut out on a main surface of the cover panel in the edge area thereof;
• the frame consists of a PMMA material, and on the one end face of the frame a circumferential web is formed in one piece, which protrudes from the end face of the frame in the direction of the frame height;
• this frame end face is connected to the ceiling panel by means of ultrasonic welding; and
• the module housing has a long-term tightness that ensures that after performing an accelerated aging treatment lasting 46 weeks, during which the module housing is always at around 50 °C and for one hour per day under ambient air pressure and for 23 hours under one, compared to the ambient air pressure 100 mbar reduced air pressure is maintained, the atmosphere in the housing interior of the module housing still consists of at least 30% by volume of argon from the originally introduced 100% Ar filling.

OBJECT OF THE PRESENT INVENTION

Proceeding from this, the object of the present invention is to provide an LED lighting module of the generic type according to the proven prior art according to the document KR 2014 0076390 A provide that has a simpler structure housing and which ensures an even better long-term tightness under the conditions of an accelerated aging treatment described above.

A further aim of the present invention consists in specifying a simple, efficient and reliably reproducible method for producing such LED lighting modules.

THE SOLUTION ACCORDING TO THE INVENTION

• das besteht aus einer Metall-Gehäuseplatte und einer transparenten Abdeckplatte, wobei je an der Metall-Gehäuseplatte und/oder an der Abdeckplatte einstückig eine umlaufende Seitenwand angeformt ist, so dass die Metall-Gehäuseplatte, die eine Seitenwand oder beide Seitenwände und die Abdeckplatte gemeinsam einen hermetisch dichten Gehäuseinnenraum begrenzen,
• in dem sich eine Platine befindet, auf der eine Anzahl je beabstandet zueinander angeordnete LEDs sitzen, und
• jeder einzelnen LED je ein Sekundäroptikelement zugeordnet ist, welches das von einer gegebenen LED erzeugte LED-Licht einfängt und entsprechend einem vorgegebenen Beleuchtungszweck richtet und bündelt,
• wobei
  • die Metall-Gehäuseplatte aus einem für Gehäuse geeigneten Leichtmetall oder aus einer Zamak-Legierung besteht;
  • die Abdeckplatte aus einem weitgehend UV-undurchlässigen oder UV-undurchlässigen PMMA-Material oder aus einem UV-stabilisierten PC-Material besteht;
  • jedes Sekundäroptikelement ein Lichtleitelement oder ein alternatives LichtleitElement aufweist, das aus dem Abdeckplattenmaterial besteht und das an der der Abdeckplatte einstückig angeformt ist; und
  • zwischen Metall-Gehäuseplatte und Abdeckplatte eine hermetisch dichte Verbindung ausgebildet ist;
• ist die erfindungsgemäße Lösung obiger Aufgabe dadurch gekennzeichnet, dass
  • jedes Lichtleitelement an der zur Platine benachbarten Innenseite der Abdeckplatte einstückig angeformt ist;
  • die hermetisch dichte Verbindung zwischen Metall-Gehäuseplatte und Abdeckplatte eine Klebeverbindung ist, die mit Hilfe eines bei Raumtemperatur aushärtenden 2-Komponenten-Acrylat-Klebstoffes erzeugt worden ist;
  • innerhalb des Gehäuseinnenraums eine argonhaltige Atmosphäre herrscht; und
  • das Modulgehäuse eine solche Langzeitdichtigkeit aufweist, die gewährleistet, dass nach Durchführung einer 46 Wochen dauernden beschleunigten Alterungsbehandlung, während der das LED-Leuchtenmodul stets bei etwa 50 °C sowie pro Tag eine Stunde (Std.) lang unter Umgebungsluftdruck sowie 23 Std. lang unter einem gegenüber dem Umgebungsluftdruck um 100 mbar verminderten Luftdruck gehalten wird, die Atmosphäre im Gehäuseinnenraum immer noch zu wenigstens 58 Vol.-% aus der ursprünglich eingebrachten 100 %-igen Ar-Befüllung besteht.

Based on a generic LED lighting module with a two-part module housing,

• This consists of a metal housing plate and a transparent cover plate, with a peripheral side wall being formed in one piece on the metal housing plate and/or on the cover plate, so that the metal housing plate, one side wall or both side walls and the cover plate together form one limit the hermetically sealed interior of the housing,
• in which there is a circuit board on which a number of spaced-apart LEDs are located, and
• a secondary optical element is assigned to each individual LED, which captures the LED light generated by a given LED and directs and bundles it according to a specified lighting purpose,
• whereby
  • the metal case plate is made of a light metal suitable for cases or of a zamak alloy;
  • the cover plate made of a largely UV-impermeable or UV-impermeable PMMA material or of a UV-stabilized PC material consists;
  • each secondary optic element comprises a light guide element or an alternative light guide element which consists of the cover plate material and which is integrally formed on the cover plate; and
  • a hermetically sealed connection is formed between the metal housing plate and the cover plate;
• the inventive solution to the above object is characterized in that
  • each light guide element is formed in one piece on the inside of the cover plate adjacent to the circuit board;
  • the hermetically sealed connection between the metal housing plate and the cover plate is an adhesive bond that has been produced using a 2-component acrylate adhesive that hardens at room temperature;
  • an argon-containing atmosphere prevails inside the housing interior; and
  • the module housing has such a long-term tightness that ensures that after performing an accelerated aging treatment lasting 46 weeks, during which the LED light module is always at around 50 °C and for one hour (hours) per day under ambient air pressure and for 23 hours under is maintained at an air pressure reduced by 100 mbar compared to the ambient air pressure, the atmosphere in the interior of the housing still consists of at least 58% by volume of the originally introduced 100% Ar filling.

The features according to the invention in the above overall combination interact in a synergistic manner in order to provide an LED lamp module that can be manufactured simply, efficiently and reliably in a reproducible manner, and that is designed for a long and maintenance-free service life. The LEDs in the LED light module are operated in an environment that can be kept largely or completely free of harmful influences over a very long period of time. A service life of the LEDs used of more than 100,000 hours (hours) can be guaranteed. Service life refers to the period of time within which the LEDs can be operated without their initial light output (lumen/watt) decreasing by more than 20%. continues to remain the initial light color is largely retained. These results are based on the following considerations and contributions.

The LED lighting module is intended to provide light that comes as close as possible to the daylight provided by the sun. Consequently, LEDs are used that deliver white or warm-white light, typically with color temperatures between 2700 and 6500 Kelvin (K), in particular with color temperatures of 3000 or 4000 or 5000 Kelvin (K). The LED semiconductor chip generates narrow-band blue light ("royal blue") at a wavelength of 442 nm (nanometers), which has to be converted into broad-band yellow light by means of fluorescence in order to achieve cool-white (color temperatures of around 5000 to 6000 K) to warm-white (color temperatures of about 2000 to 3000 K) light. This fluorescence is provided by selected powdered, yellow to orange-colored phosphors, such as cerium-doped yttrium aluminum garnet, which are applied as a layer on the LED semiconductor chip. This phosphor layer is covered with a layer of a silicone material, or encapsulated with this silicone material. This silicone encapsulant is particularly close to the LED semiconductor die and is exposed to the heat and "high photon energy" generated by the LED semiconductor die during LED operation. Often there is a lens or a dome made of additional silicone material on this silicone encapsulating material, with which the radiation of the light emitted by the LED is already directed and controlled to a limited extent in the sense of primary optics; this latter silicone material is also referred to as silicone lens material. Experience shows that these two silicone materials are not damaged by the blue light generated by the LED semiconductor chip with an emission maximum at around 442 nm.

However, the atmosphere inside the housing can contain incompatible organic compounds (experts speak of VOCs , derived from volatile organic compounds) that can outgas from various sources, such as adhesives, coatings on a printed circuit board, certain soldering materials, as well as sealants and gaskets such as O-rings and the like. These VOCs diffuse into these silicone materials, lodge and become trapped in voids between the silicone polymer chains. Subsequent exposure to the "high photon energy" produced by the LED, the heat generated by the operation of the LED, and other environmental factors will discolor the VOCs trapped or "trapped" in the silicone encapsulant and silicone lens material. This discoloration of the trapped VOCs can damage the light emitted by the LED. This discoloration occurs in particular with LEDs producing blue light; however, this blue light is required to provide white light that corresponds to daylight. Such damage to the light emitted by the LEDs can lead to complete failure of the LED lamp module.

It is also known that moisture affects the operation of LEDs that produce white light. Therefore, LEDs that produce white light are typically operated in a water and water vapor-free inert gas atmosphere, such as argon. Within the scope of the present invention, it was recognized that UV components of sunlight can also have harmful effects on LEDs that produce white light, which can affect precisely these VOCs. On a typical street light, the transparent cover plate is not directly exposed to sunlight, but faces the ground. However, scattered and/or reflected sunlight can enter the interior of the module housing through the transparent cover plate and cause long-term damage to the silicone encapsulant material, the silicone lens material, and/or the VOCs trapped within these silicone materials. An important aspect of the present invention is therefore to prevent harmful UV components of sunlight from penetrating into the interior of the module housing, which is why the cover plate, including the secondary optics elements molded onto it in one piece, consists of a largely UV-opaque or a completely UV-opaque, transparent plastic is made. According to the invention, a largely UV-impermeable or UV-opaque PMMA material or a UV-stabilized PC material is provided here. In detail, materials are selected that not only provide the necessary UV protection, but also for the LED light generated - depending on the layer thickness to be penetrated - also ensure a high transmission of up to 92% and also have the necessary weather resistance to be able to use an LED light module with such a cover plate outdoors for many years.

ADVANTAGEOUS FEATURES

Advantageous refinements and developments of the invention are described below; in some cases, such configurations are also the subject of dependent claims.

The LED lamp module according to the invention has a module housing consisting of two components; one component is a plate-shaped housing part made of metallic material, which is referred to below only briefly as the metal housing plate. This metal housing plate can consist of a light metal or a zamak alloy. It is known that metals that have a density of less than 5.0 g/cm ³ are referred to as light metals. In the case of a light metal, light metals suitable for housing materials that form a permanently protective and weatherproof surface layer in the ambient air come into consideration, here in particular light metals based on aluminum (Al), magnesium (Mg), titanium (Ti) and beryllium (Be) .

• Aluminium (Al),
• AI-Legierungen mit Beimengungen an Si, Cr, Mg, Fe, Cu, Mn, Ti und/oder Zn, typischerweise je in Anteilen kleiner 1 %;
  Al-Si-Legierungen mit einem Si-Anteil von 10,0 bis 13,0 % und kleineren Anteilen an Mg, Fe, Mn, Ni, Zn,und/oder TI typiscerweise kleiner als 0,5 %
• Magnesium (Mg) und
• Zamak-Legierungen die neben dem Hauptbestandteil Zn kleinere Anteile an Al, Cu und/oder Mg enthalten können.

According to the invention, the metal housing plate preferably consists of a housing material that is selected from a group that includes:

• aluminum (Al),
• Al alloys with additions of Si, Cr, Mg, Fe, Cu, Mn, Ti and/or Zn, typically in proportions of less than 1%;
  Al-Si alloys with a Si content of 10.0 to 13.0% and smaller amounts of Mg, Fe, Mn, Ni, Zn, and/or TI typically less than 0.5%
• Magnesium (Mg) and
• Zamak alloys which, in addition to the main component Zn, can contain small amounts of Al, Cu and/or Mg.

Metal injection molding can be used to obtain castings from these housing materials, on which even small details with dimensions of 0.1 mm can be realized faithfully and repeatably. The castings are relatively light weight, corrosion and weather resistant, and have good thermal conductivity. Alternatively, suitable housing parts can also be obtained by deep-drawing pre-products. The aluminum alloy "6061-T6 aluminum" is particularly preferably used as the light-metal housing material, which contains 0.8 to 1.2% Mg and 0.4 to 0.8% Si as the main alloying elements. Mechanically stable and durable castings can be produced with very fine details, even on the order of 0.1 mm; the cast parts have a comparatively high thermal conductivity of up to about 170 W/(m K) for Al cast parts.

The second component of the module housing according to the invention is a transparent cover plate onto which a number of light-guiding elements consisting of the cover plate material are integrally formed and integrated. UV-opaque or UV-opaque PMMA material is largely used as the cover plate material; PMMA stands for polymethyl methacrylate. Here, "UV-opaque" means that more than 99% of incident UV radiation with a wavelength of 400 nm or less is absorbed and blocked. UV-stabilised PC material can be considered as an alternative cover plate material; PC stands for polycarbonate. "UV stabilized" here means that the PC material is provided with a UV stabilizer throughout the mass, which blocks incident UV radiation. The cover plate, including the light guide elements, forms a body with a complex three-dimensional contour and must be produced from meltable starting material using an injection molding process; typically powdered or pelleted starting materials are used. Substantially UV-opaque or UV-opaque, pellet-shaped PMMA material as well as UV-stabilized pellet-shaped PC material is commercially available.

Typical suppliers of pellet-shaped PMMA in Europe are the companies of the ALTUGLAS INTERNATIONAL GROUP, for example in 97100 Bronderslev, Denmark or in 59700 Marcq-en-Baroel, France. Selected and specific types of PMMA can be procured that have high scratch resistance, high impact strength, have high weather resistance and/or a high glass transition temperature. According to the invention, the cover plate has been injection molded from a granular PMMA material sold by CHI MEI CORPORATION, San Chia, Jen Te District, Tainan City, TAIWAN under the trade name PMMA ^ACRYREX® (ACRYREX is a registered trademark). This PMMA material has a density of 1.19 g/cm ³ , a tensile strength of 67 MPa, a Vicat softening point of 107°C and a refractive index of about 1.49. The material is available in the form of granules with an average particle size of 3 mm. The granules are heated to a temperature of around 220 °C, forming a medium-viscosity melt. This melt is processed under a pressure of about 700 bar to form a plate-shaped injection molded body. After cooling, this body is finely machined to obtain a light guide cover plate having rounded corner portions and bevelled edges.

• eine, an einer 3 mm dicken Platte nach ASTM D1003 bestimmte Lichtdurchlässigkeit von 88 bis 89 %;
• eine an einer 3,2 mm dicken Platte nach ASTM D1003 bestimmte Trübung (Haze) kleiner 0,8 %; und
• einen nach ASTM D542 bestimmten Brechungsindex von 1,585.

A UV stabilized PC material well suited for the present purposes is marketed by CHI MEI CORPORATION, 59-1, San Chia, Jen Te, Tainan City 71702, Taiwan under the trade name "WONDERLITE PC" ( ^WONDERLITE® is a registered trademark). ; The UV-stabilized WONDERLITE PC materials PC-110U, PC-115U and PC-122U are particularly suitable for the present purposes. These materials include:

• a light transmittance of 88-89% as determined on a 3mm thick sheet according to ASTM D1003;
• a haze determined on a 3.2 mm thick plate according to ASTM D1003 of less than 0.8%; and
• a refractive index of 1.585 as determined by ASTM D542.

Workpieces of "optical quality" can be produced from these materials. According to an essential aspect of the present invention, light guide elements are integrally formed and integrated on the transparent cover plate. An LED would typically emit first LED light rays uniformly in all spatial directions radiate hemispherical space. The light guide elements preferably provided here provide transparent material with a high refractive index on the path of these first LED light beams, which modifies the light distribution pattern of these first light beams in such a way that finally a rectangular road surface can be uniformly illuminated that has a comparatively large length and a comparatively small has width; typically this length is eight to ten times the width.

According to the invention, a number of identical light-guiding elements are formed in one piece on the inside of the cover plate adjacent to the circuit board, all of which are arranged in the same arrangement or orientation. All light guide elements produce the same light distribution pattern. It is sufficient to describe a single light guide element.

A light guide element that is particularly preferred according to the invention forms an additional flat, approximately cuboid layered body on the inside of the cover plate, which is about 25 mm long, about 20 mm wide, about 3 to about 4 mm thick and has a layered body surface; a first cavity and two second cavities being formed in this laminated body, all of which are open to the laminated body surface. "About" is intended to mean a range of the given value ranging from 10% smaller to 10% larger; a width of about 20 mm thus includes widths of 18.0 to 22.0 mm

The first cavity is arranged in the center of the light-guiding element, forms the focus of the light-guiding element and is used to hold an LED; the surface of the layered body is then in contact with the circuit board.

The larger second cavity has a contour which is strongly convexly curved with respect to the focus and is inclined with respect to the plane of the cover plate, the apex of which is directed towards the focus.

The smaller, second cavity has a contour that is moderately convexly curved with respect to the focus and is inclined relative to the plane of the cover plate, the apex of which is on the focus is on. On the surface of these contours, there is a total reflection of LED light beams that hit these surfaces from the inside of the layered body. The layered body has two longer, parallel, planar sides, the direction or extension of which defines a long-side direction and a short-side direction of the light-guiding element that is orthogonal thereto. Further, over each layered body on the outside of the cover plate is integrally formed a coextensive, moderately convex curved bulge made of the cover plate material and having an apex line oriented parallel to the short-side direction of the light guide member. On the surface of this curvature, the LED light beams that have passed the cover plate are deflected in the direction of the longitudinal center of the road surface to be illuminated.

A light guide with all of these features modifies the LED light distribution pattern optimally for street lighting purposes and can be used for all LEDs intended for street lighting purposes on the market. With the aid of an LED lighting module according to the invention, which is fitted with a number of LEDs, with the LED light of each LED being modified with a light-guiding element of the type described above, at least the roadway luminance can be obtained for dry and wet road surfaces which according to DIN EN 13201 -2 is required for Me lighting classes Me5 and Me6.

According to a further embodiment of the present invention, an alternative cover plate with alternative light-guiding elements can be used. The essential difference is that the convex contours of the light-guiding element described above are replaced in the alternative light-guiding element by truncated cone lateral surfaces and conical lateral surfaces. The asymmetrical luminance distribution desired for street lighting can be increased even further. Furthermore, a flat lens design can be implemented in which the LED light otherwise trapped in the module housing is redirected in other usable directions in the light guide element, which means that the light output can be increased by up to 7% compared to conventional lights of this type.

The LED lamp module according to the invention has a closed, hermetically sealed module housing in which a number of LEDs can generate LED light. Each glowing LED converts about 2/3 of the supplied electrical energy into heat. Excessive heating of the LEDs and the module housing must be avoided in order not to impair the useful life of the LEDs.

The LED lamp module according to the invention is to be attached to the rear part of the street lamp via the back of its metal housing plate. Preferably, a number of flanges arranged in pairs are integrally formed on the rear side of the metal housing plate, each flange forming a pair of flanges. When the LED light module is placed on the rear part of the street light, each pair of flanges enters a complementary groove cut out there, which has such dimensions that a pressure is generated between the groove flanks and the outer flanks of the pair of flanges entering. This pressure ensures a particularly good, unhindered heat transfer between the metal housing plate on the LED light module and the relatively large rear part of the street light.

On the LED lamp module housing according to the invention, there is a hermetically sealed adhesive connection between the metal housing plate and the cover plate explained above, which has been produced with the aid of a 2-component acrylate adhesive which cures at room temperature.

• einen ersten Klebstoff aus 10 Vol.-Teilen Methacrylsäuremethylester-A-Komponente und 1 Vol.-Teil Peroxid-B-Komponente; oder
• einen zweiten Klebstoff aus 1 Vol.-Teil Methacrylsäuremethylester-A-Komponente und 1 Vol.-Teil Methacrylsäuremethylester-B-Komponente; oder
• einen dritten Klebstoff aus 1 Vol.-Teil 2-Cyanacrylsäureethylester-A-Komponente und 1 Vol.-Teil Epoxidharz-Komponente.

An adhesive can preferably be used here, which is selected from a group that includes:

• a first adhesive of 10 parts by volume methyl methacrylate component A and 1 part by volume peroxide component B; or
• a second adhesive of 1 part by volume methyl methacrylate component A and 1 part by volume methyl methacrylate component B; or
• a third adhesive composed of 1 part by volume 2-cyanoacrylic acid ethyl ester A component and 1 part by volume epoxy resin component.

The first adhesive is sold, among others, by Adchem GmbH, 90530 Wendelstein, DE under the trade name ^ACRALOCK® ( ^ACRALOCK® is a registered trademark); according to the invention, the product "ACRALOCK SA 10-05 LV" is used here in particular. It is a primerless metal and plastic adhesive that is excellent for bonding Al and plastics such as PMMA and PC. Peroxide-induced radical polycondensation delivers a fully reacted, cured product that emits no volatile organic compounds (VOCs). The hardened adhesive is impact-resistant, UV-stable and shows very high weather resistance.

The second adhesive is marketed inter alia by Permabond Engineering Adhesives Ltd., Hampshire, UK under the trade name ^Permabond® ( ^Permabond® is a registered trademark); according to the invention, the products "Permabond TA4202" (with lower viscosity and a maximum gap filling capacity of up to 0.5 mm) or "Permabond TA4200" (with higher viscosity and a maximum gap filling capacity of up to 4 mm) are used here in particular. It is a structural 2-part 1:1 acrylic methyl ester based adhesive system ideal for bonding a wide range of materials including Al, PMMA and PC; For example, shear strengths (according to ISO 4587) of 3 to 6 N/mm ² are obtained on untreated Al, 3 to 4 N/mm ² on PMMA and 3 to 4 N/mm ² on PC.

The third adhesive is one of the ^LOCTITE® products sold by Henkel AG & Co. KGaA, 40191 Düsseldorf, DE ( ^LOCTITE® is a registered trademark); According to the invention, the products "LOCTITE HY 4080" and "LOCTITE HY 4090" (with a particularly high final strength on PC) are used here in particular. The adhesives show good gap filling properties and are also suitable for applications that are exposed to high temperatures and/or high humidity.

According to the invention, the product ACRALOCK SA 10-05 LV is particularly preferably used as the adhesive because the peroxide-induced free-radical polycondensation yields a fully reacted, cured product that releases no volatile organic constituents or components (VOCs).

The lighting module housing provided according to the invention should have a particularly high level of long-term tightness. In addition to the selection of specific adhesives, a specific adhesive joint designed according to the invention is also provided for this purpose in the peripheral area of the light metal housing plate and cover plate.

• am Plattenrandinnenumfang der Metall-Gehäuseplatte ein zum Plattenboden stufenförmig abfallender umlaufender Sockel einstückig angeformt ist, auf dem eine aufrechte, umlaufende und ununterbrochene Drei-Flansch-Dichtkontur sitzt, die am Sockel einstückig angeformt ist und die aufweist - benachbart und beabstandet zum Plattenrandinnenumfang - einen Außenflansch, einen dazu beabstandeten Mittelflansch und einen dazu beabstandeten Innenflansch; und
• ferner an der Abdeckplatte - benachbart und beabstandet zu deren Seitenwand an deren Innenseite - eine umlaufende und ununterbrochene Drei-Nuten-Dichtzone ausgebildet ist, die eine Außennut, eine Mittelnut und eine Innennut aufweist, und diese Drei-Nuten-Dichtzone komplementär zur Drei-Flansch-Dichtkontur an der Metall-Gehäuseplatte ausgebildet ist; und
• nach Einbringen von flüssigem oder plastischem Klebstoff in die Mittelnut und nach Anlage der Abdeckplatte an der Metall-Gehäuseplatte zwischen Drei-Flansch-Dichtkontur und Drei-Nuten-Dichtzone ein ununterbrochener Spalt gebildet ist, der mit einem ununterbrochenen Klebstoffstrang gefüllt ist.

It is preferably provided for the design of the adhesive joint according to the invention that

• on the inner periphery of the plate edge of the metal housing plate, a circumferential base is integrally formed which slopes down in steps towards the plate floor, on which an upright, circumferential and uninterrupted three-flange sealing contour sits, which is integrally formed on the base and which has - adjacent to and at a distance from the inner periphery of the plate edge - an outer flange , a center flange spaced therefrom and an inner flange spaced therefrom; and
• further formed on the cover plate - adjacent and spaced from its side wall on the inside thereof - is a circumferential and uninterrupted three-groove sealing zone having an outer groove, a central groove and an inner groove, and this three-groove sealing zone complementary to the three-flange - the sealing contour is formed on the metal housing plate; and
• After introducing liquid or plastic adhesive into the central groove and after the cover plate has been placed against the metal housing plate, an uninterrupted gap is formed between the three-flange sealing contour and the three-groove sealing zone, which is filled with an uninterrupted strand of adhesive.

This adhesive line preferably extends uninterruptedly from a first adhesive line in the outer groove, which is parallel to the plane of the cover plate, to a second adhesive line in the inner groove, which is parallel to the plane of the cover plate.

A first and/or second adhesive strand level, each parallel to the plane of the board, cannot be perceived optically, so that the adhesive used to produce the adhesive connection does not cause any visible soiling. Because the second layer of adhesive adjoining the interior of the housing has a comparatively small cross-sectional area, typically less than 1.2 cm ² , a noteworthy escape of VOCs from the polymerized and cured adhesive at this adhesive cross-sectional area is not to be expected. On the other hand, a comparatively long, uninterrupted line of adhesive is formed between the first adhesive line level and the second adhesive line level, which offers an insurmountable resistance to the escape of argon from the interior of the housing and/or the entry of air and moisture from the external environment into the interior of the housing; a particularly high long-term tightness of the module housing is obtained.

• Mittelleistungs-LEDs eingesetzt werden, die bei einer Flußspannung von etwa 2,7 bis etwa 2,9 Volt mit einer maximalen Leistungsaufnahme von etwa 3 Watt (W) betrieben werden; und
• die Platine solche Abmessungen hat, dass für jede Mittelleistungs-LED wenigstens eine Platinenfläche von 5 bis 9 cm² zur Verfügung steht.

In the hermetically sealed interior of the housing, which is delimited by the metal housing plate, cover plate and adhesive connection, there is a printed circuit board on which a number of LEDs are located. A glowing LED converts about 2/3 of the supplied energy into heat. On the other hand, the average operating temperature of a lit LED should not exceed around 85 °C in order not to impair its usable long-term service life. The LED lamp module according to the invention has a comparatively small housing interior. In order to nevertheless avoid excessive heating of the glowing LEDs, it is preferably provided according to the invention that

• medium-power LEDs are used, which are operated at a forward voltage of about 2.7 to about 2.9 volts with a maximum power consumption of about 3 watts (W); and
• the board has dimensions such that at least one board area of 5 to 9 cm ² is available for each medium-power LED.

Medium power LEDs well suited for the purposes of the present invention are sold, for example, by Samsungs Electronics Co., Ltd., Yongin-si, Gyeonggi-do, 446-711 KOREA under the trade designation LM101A; such medium-power LEDs from the LM101A series are available with color temperatures of 6500 to 2700 Kelvin, for example.

Provided that the circuit board is made of a material with good thermal conductivity, such as the aluminum alloy "6061-T6 aluminum" that is preferably used, and this circuit board is in good thermal contact with the metal housing plate, which in turn is in good heat conduction with the light metal back of a lamp of sufficient size , good dissipation of the process heat generated during operation of the LEDs can be achieved with such circuit board dimensions, so that without complex heat management and/or without additional cooling measures, heating of the LEDs to temperatures above 80 °C is reliably avoided even if they are operated for hours. A long service life of the LEDs of 100,000 operating hours and more can be achieved; operating the LEDs with limited power consumption of less than or equal to about 3 watts (W) of the LEDs increases their efficiency, improves efficiency and extends the usable service life of the LEDs.

According to a further advantageous embodiment, a board is placed inside the housing interior on the base plate of the metal housing plate; and a graphite foil is inserted between the base plate and the circuit board.

An LED mounted on the circuit board forms a point source of heat that can typically reach an operating temperature of around 85 °C. A heat propagation cone emanates from this heat source. The graphite foil inserted between the circuit board and the base plate spreads and expands this heat propagation cone and thus improves the heat dissipation from the light-emitting LED via the metal housing plate to a solid light metal back of a street lamp.

As already stated above, a circumferential and uninterrupted three-groove sealing zone is formed on the cover plate--adjacent to and spaced from the side wall on the inside thereof--which has an outer groove, a central groove and an inner groove.

According to an advantageous embodiment of the method according to the invention, a liquid or plastic adhesive is introduced into the central groove of the three-groove sealing zone, namely a room temperature-curing 2-component acrylate adhesive based on acrylic acid ester, with which a hermetically sealed adhesive bond between metal and Housing plate and cover plate is generated. A methyl methacrylate-based 2-component acrylate adhesive, which is cured by peroxide-induced radical polycondensation, is particularly preferably used as the 2-component acrylate adhesive.

The faceplate coated with this adhesive is brought into abutment with the metal case plate until a faceplate sidewall face abuts a socket on the metal case plate. Preferably, this engagement can be assisted by applying mechanical compressive force to the cover plate while holding the metal housing plate in place; a compressive force of up to 100 N can preferably be exerted.

After such a system, an uninterrupted gap is formed between the three-flange sealing contour and the three-groove sealing zone, which gap is filled with an uninterrupted strand of adhesive. Preferably, such an amount of adhesive is introduced so that an adhesive strand is formed which extends uninterruptedly from a first adhesive strand level in the outer groove, parallel to the plane of the panel, to a second adhesive strand level in the inner groove, parallel to the plane of the panel - in each case at the three-groove sealing zone .

According to a further advantageous embodiment of the method according to the invention - after the production and curing of the adhesive connection on the module housing of the LED lighting module that has been completed to this extent - a leak test is carried out, for which purpose the gas pressure in the housing interior of the module housing is reduced to a value of 100 mbar or less.

Failure of this leak test is an exclusion criterion; faulty module housings can be identified and discarded.

Further preferably, before and during the leak test, the module case can be heated to a moderately high temperature of about 50 to 80°C, and the depressurization can be performed for a while.

With the help of such a treatment, stubbornly adhering VOCs can also be removed from the housing interior of the module housing. The color change of the emitted light to be expected over a long period of operation of a high-performance LED and a decrease in the light output can be slowed down even further.

With the present invention, an LED lighting module can be provided with such a module housing, which has a long-term tightness that ensures that, after an accelerated aging treatment lasting 46 weeks, during which the module housing is always at about 50 °C and one hour per day (hour) under ambient air pressure and for 23 hours under an air pressure reduced by 100 mbar (millibar) compared to the ambient air pressure, the atmosphere in the housing interior of the module housing still consists of at least 58% by volume of argon from the originally introduced 100% -igen Ar filling exists.

In this way, the LEDs that generate white light in an LED lamp module according to the invention can also be operated under a protective atmosphere over a long service life of at least 20 years.

DETAILED DESCRIPTION

Fig. 1

anhand einer Schrägbilddarstellung eine Straßenleuchte, an der ein erfindungsgemäßes LED-Leuchtenmodul angebracht ist;

Fig. 2

anhand einer Schrägbild-Explosionsdarstellung das von der Straßenleuchte getrennte LED-Leuchtenmodul;

Fig. 3

anhand einer Schrägbild-Explosionsdarstellung die wesentlichen Bestandteile des LED-Leuchtenmoduls, nämlich Metall-Gehäuseplatte, Platine mit LEDs und transparente Abdeckplatte in je einer Anordnung, in der das an der Straßenleuchte befindliche LED-Leuchtenmodul eine Straßenfläche beleuchten könnte;

Fig. 4a

eine Schrägansicht der Rückseite der Metall-Gehäuseplatte;

Fig. 4b

eine Schrägansicht der Sichtseite der Metall-Gehäuseplatte;

Fig. 4c

eine Schrägansicht der Außenseite der transparenten Abdeckplatte;

Fig. 4d

die längs der Schnittlinie B-B aus Fig. 4c erhaltene Schnittdarstellung;

Fig. 5a

eine ausschnittsweise, stark vergrößerte Schnittdarstellung einer Drei-Flansch-Dichtkontur im Umfangsbereich der Metall-Gehäuseplatte;

Fig. 5b

eine ausschnittweise, stark vergrößerte Schnittdarstellung einer Drei-Nuten-Dichtzone im Umfangsbereich der Abdeckplatte;

Fig. 5c

eine ausschnittsweise, stark vergrößerte Schnittdarstellung des Spaltes, der nach Anlage der Abdeckplatte an die Metall-Gehäuseplatte zwischen Drei-Flansch-Dichtkontur und komplementärer Drei-Nuten-Dichtzone verbleibt;

Fig. 6a

eine im Verhältnis 1 : 4 vergrößerte Darstellung einer Draufsicht auf ein einzelnes Lichtleitelement;

Fig. 6b

die längs der Schnittlinie A-A aus Fig. 6a erhaltene Schnittdarstellung;

Fig. 6c

eine Draufsicht auf vier aneinandergrenzende Lichtleitelemente nach Fig. 6a;

Fig. 6d

eine Schrägansicht der Abdeckplatte, an deren Innenseite eine ganze Anzahl aneinandergrenzender Lichtleitelemente einstückig angeformt ist;

Fig. 7

in einer Schrägbilddarstellung ein erfindungsgemäßes LED-Leuchtenmodul;

Fig. 8

fünf Spektren von, im Innenraum des Modulgehäuses befindlichen Gaszusammensetzungen, die unterschiedliche Anteile an Argon (Ar) enthalten;

Fig. 9

fünf Spektren von, im Innenraum des Modulgehäuses befindlichen Gaszusammensetzungen, die an verschiedenen Tagen im Verlauf einer 46-wöchigen beschleunigten Alterungsbehandlung des Modulgehäuses aufgenommen worden sind;

Fig.10

anhand einer graphischen Darstellung die - hier unter den genannten Voraussetzungen - zu erwartende Abnahme des Ar-Gehaltes der im Innenraum eines Modulgehäuses enthaltenen Gaszusammensetzung während der zu erwartenden Lebensdauer des LED-Leuchtenmoduls;

Fig. 16a

eine alternative Abdeckplatte mit alternativen Lichtleitelementen;

Fig. 16b

eine Draufsicht auf ein einzelnes isoliertes alternatives Lichtleitelement, das im Maßstab 1 : 4 vergrößert dargestellt ist;

Fig. 16c

ein Schnittbild, das bei einem Schnitt längs der Schnittlinie A - A' am alternativen Lichtelement nach Fig. 16b erhältlich ist;

Fig. 16d und 16e

je eine orthogonale Seitenansicht des alternativen Lichtleitelementes nach Fig. 16b; und

Fig. 16f

anhand eines Diagrammes die bei Einsatz der alternativen Abdeckplatte erhältliche unterschiedliche Leuchtdichtenverteilung in einerseits der C0 - C 180 Richtung und andererseits der C90 - C270 Richtung.

In the following the invention will be explained in more detail by means of preferred embodiments with reference to drawings; the latter show with:

1

a street lamp on which an LED lamp module according to the invention is attached using an oblique representation;

2

using an oblique exploded view, the LED lamp module separated from the street lamp;

3

using an oblique exploded view of the essential components of the LED lamp module, namely metal housing plate, circuit board with LEDs and transparent cover plate, each in an arrangement in which the LED lamp module located on the street lamp could illuminate a street surface;

Figure 4a

an oblique view of the back of the metal housing plate;

Figure 4b

an oblique view of the visible side of the metal housing plate;

Figure 4c

an oblique view of the outside of the transparent cover plate;

Figure 4d

those along the cutting line BB Figure 4c preserved sectional view;

Figure 5a

a fragmentary, greatly enlarged sectional view of a three-flange sealing contour in the peripheral area of the metal housing plate;

Figure 5b

a fragmentary, greatly enlarged sectional view of a three-groove sealing zone in the peripheral area of the cover plate;

Figure 5c

a fragmentary, greatly enlarged sectional view of the gap that remains after the cover plate has been attached to the metal housing plate between the three-flange sealing contour and the complementary three-groove sealing zone;

Figure 6a

a ratio of 1: 4 enlarged representation of a plan view of a single light guide element;

Figure 6b

those along the section line AA Figure 6a preserved sectional view;

Figure 6c

a top view of four adjacent light guide elements Figure 6a ;

Figure 6d

an oblique view of the cover plate, on the inside of which a whole number of adjacent light-guiding elements are integrally formed;

7

in an oblique representation of an inventive LED lighting module;

8

five spectra of gas compositions inside the module housing that contain different proportions of argon (Ar);

9

five spectra of gas compositions in the interior of the module housing, which were recorded on different days during a 46-week accelerated aging treatment of the module housing;

Fig.10

on the basis of a graphic representation of the expected reduction in the Ar content of the gas composition contained in the interior of a module housing—here under the conditions mentioned—during the expected service life of the LED lamp module;

16a

an alternative cover plate with alternative light guide elements;

Figure 16b

a plan view of a single isolated alternative light guide, which is shown enlarged at a scale of 1: 4;

Figure 16c

a sectional image that follows the alternative light element in a section along the section line A - A' Figure 16b is available;

Figures 16d and 16e

according to an orthogonal side view of the alternative light guide element Figure 16b ; and

16f

based on a diagram, the different luminance distribution available when using the alternative cover plate in the C0 - C 180 direction on the one hand and the C90 - C270 direction on the other.

• eine "kleine Straßenleuchte", die typischerweise in einer Höhe von 4 bis 6 m über der zu beleuchtenden Fläche angeordnet wird, die mit 12 Mittelleistungs-LEDs bestückt ist, und die bei Aufnahme einer elektrischen Leistung von 35 W einen Lichtfluss bis zu etwa 4400 Im liefert; ferner
• eine "mittelgroße Straßenleuchte", die typischerweise in einer Höhe von 6 bis 10 m über der zu beleuchtenden Fläche angeordnet wird, die mit 36 Mittelleistungs-LEDs bestückt ist, und die bei Aufnahme einer elektrischen Leistung von 100 W einen Lichtfluss bis etwa 12.500 Im liefert; und
• eine "große Straßenleuchte", die typischerweise in einer Höhe von 8 bis 14 m über der zu beleuchtenden Fläche angeordnet wird, die mit 64 Mittelleistungs-LEDs bestückt ist, und die bei Aufnahme einer elektrischen Leistung von 180 W einen Lichtfluss bis zu etwa 22.500 Im liefert.

The LED lamp module according to the invention is preferably used as a light-generating element or as a lamp in a street lamp. The applicant has developed streetlights of different dimensions,
for example

• a "small street lamp", which is typically arranged at a height of 4 to 6 m above the area to be illuminated, which is fitted with 12 medium-power LEDs and which consumes an electrical power of 35 W and has a luminous flux of up to around 4400 lm supplies; further
• a "medium-sized street light", which is typically placed at a height of 6 to 10 m above the area to be illuminated, which is fitted with 36 medium-power LEDs and which supplies a luminous flux of up to around 12,500 lm while consuming an electrical power of 100 W ; and
• a "large street light", which is typically arranged at a height of 8 to 14 m above the area to be illuminated, which is equipped with 64 medium-power LEDs and which, with an electrical power consumption of 180 W, has a luminous flux of up to around 22,500 lm delivers.

Without intending to be limited to use in specific streetlights with specific dimensions, the present invention will be described in detail below with reference to an inventive LED lighting module intended for such a "small streetlight" having a flat, approximately rectangular shape with a length of about 250 mm, with a width of about 220 mm and with a thickness/height of about 20 mm.

Fig.1 shows a street lamp 1, which can be attached to a vertically aligned mast 2 at different angles. The street lamp 1 has a back part 3 on which a service part 4 and an inventive LED lamp module 5 can be attached in a detachable manner; the service part 4 contains transformers, rectifiers, driver circuits and other elements of the LED power supply, as well as signal receiving, control and regulation electronics and is provided with an adjustable bracket, via which the entire street light 1 can be attached to the mast 2.

2 shows the LED lamp module 5 separated and removed from the back part 3 in a kind of exploded view. Metal housing plate 10 and cover plate 60 delimit a housing interior 9 within the module housing 8. 3 shows in a kind of exploded view the metal housing plate 10, the cover plate 60 separated and removed from the housing plate 10 and in between a circuit board 40 equipped with a number of LEDs 44, which is placed on a flat plate base 22 of the metal housing plate 10 and fixed there . 2 and 3 12 show the metal housing plate 10 and the cover plate 60 in an arrangement in which the LED lamp module 5 located on the street lamp 1 could illuminate a street surface.

the Figure 4a and Figure 4b show the metal housing plate 10 in an inverted configuration revealing more detail; the Figure 4c shows the cover plate 60 in another view; the Figure 4c shows a schematic sectional view of a section of the cover plate, on the inside of which a light-guiding element is formed in one piece, and on the outside of which a curvature with the same area as the light-guiding element is formed.

This metal case plate 10 is made of a light metal suitable for case materials or a zamak alloy, typically Al, an Al alloy, or an Al-Si alloy, may be painted, and has a substantially rectangular shape Shape. In the case of the lamp module intended for a "small street lamp", this metal housing plate 10 has a length of approximately 250 mm, a width of approximately 220 mm and a thickness of less than 20 mm. Two brackets 14 and 14' are formed on one narrow side, with which the metal housing plate 10 can be hinged to the service part 4 in the manner of a hinge. the Metal housing plate 10 has a - according to the illustration 3 bottom visible side 15 and a removed top back 16.

Like in particular Figure 4a As can be seen, flanges 17 and 17' arranged in pairs are integrally formed on the rear side 16 of the metal housing plate 10. The two flanges 17 and 17' of a pair of flanges are separated from one another by a gap 19 and are spaced apart from one another. The two flanges 17 and 17' of a pair of flanges have dimensions and mechanical strengths such that they can be deformed slightly towards one another when considerable forces are applied. The two outer flanks 18 and 18' of a pair of flanges are positioned at a slight angle relative to a vertical on the plane of the housing plate and are inclined toward one another. Each pair of flanges is assigned a groove in the bottom of the back part 3 of the street lamp 1, which has such dimensions that when a pair of flanges is inserted with considerable force into the assigned groove, the outer flanks 18 and 18' sliding on the flanks of the groove are slightly deformed towards one another. The outer flanks 18 and 18 ′ of a pair of flanges should rest under pressure on the flanks of the grooves in the back part 3 , which promotes heat transfer from the metal housing part 10 to the back part 3 of the street lamp 1 .

In each corner area of the metal housing plate 10 a hole 13 is cut out, through which a screw can be passed, with which the LED lamp module 5 can be attached via its metal housing plate 10 to the back part 3 of the street lamp 1 under considerable contact pressure; the surfaces that come into contact with each other should be blank and bare to enable good, unhindered heat transfer.

Like in particular Figure 4b and 5b As can be seen, the metal housing plate 10 has a flat recess 20 which is open towards the visible side 15 and is delimited by a flat plate base 22 and a peripheral plate edge section 25 which has a plate edge inner circumference 26 . The recess 20 has a rectangular shape with straight sides and rounded corners; in the case of the one considered here LED light module for a "small street light" this recess 20 has a length of about 170 mm, a width of about 145 mm and a depth, which is the distance from the plate bottom 22 to the flat surface of the plate edge section 25, of about 7 mm. A one-piece molded peripheral base 27 connects to the inner periphery 26 of the plate edge, which forms a step that slopes down to the plate bottom 22 . On this base 27 sits - adjacent to and spaced from the plate edge inner circumference 26 - an integrally formed on the base 27 upright, circumferential and uninterrupted three-flange sealing contour 30, which - significantly enlarged - with Figure 5b shown and explained in detail below.

A printed circuit board 40 is prepared, on which a number of LEDs 44 are attached. This circuit board 40 can consist of a 1.5 mm thick Al plate on which there is an insulating coating on which the conductor tracks of an electrical circuit are applied; in the case of an LED lamp module according to the invention for a “small street lamp”, this Al plate can have dimensions of 130 mm×120 mm, for example. The LEDs are arranged in multiple rows aligned parallel to the longer side of the board. Medium-power LEDs are preferably used, each of which is operated with a power consumption of less than or equal to 3 watts (W).

A distance of at least 20 mm and preferably an even larger distance is provided between two adjacent LEDs in both orthogonal surface directions. Each LED 44 can be arranged in the focus of a cuboid light-guiding element which, within the scope of the present invention, preferably has dimensions of approximately 20 mm×approximately 25 mm and which rests on circuit board 40 . An effective dissipation of the operating heat of a luminous medium-power LED operated under the above conditions can be achieved without complex temperature management if each individual LED maintains a distance of more than 20 mm from each adjacent LED, and the circuit board 40 has such dimensions that each individual LED at least a circuit board area of 5 to 9 cm ² is available.

The conductor tracks leading to the LEDs 44 are connected to connection pieces 45 . Furthermore, thermal sensors 47 are mounted on the circuit board 40 and are connected to contact pieces 48 .

According to an important aspect of the present invention, apart from the components mentioned above, such as LEDs 44, thermal sensors 47 and connection and contact pieces 45, 48, no other electrical and / or electronic components provided. Instead, such components, including transformers, rectifiers, driver circuits and the like, are provided exclusively in the service part 4, which is fastened to the back part 3 of the street lamp, which consists of a light metal with good thermal conductivity.

The circuit board 40 prepared in this way is placed on the panel base 22 of the metal housing panel 10 within the three-flange sealing contour 30 . A graphite foil 23 can be inserted between circuit board 40 and panel base 22 in order to improve the heat transfer between circuit board 40 and metal housing panel 10 . With the aid of a number of screws 42 which can be screwed into blind holes cut out in the metal housing plate 10 , the circuit board 40 is pressed tightly and firmly against the flat plate base 22 . A pair of cables 46 is connected to the two connecting pieces 45, via which the LEDs on the circuit board 40 are supplied with current and voltage. The signals of the thermal sensor 47 are fed to the contact piece 48 via conductor tracks of the electrical circuit, to which in turn a conductor bundle 49 is connected.

These conductors 46, 49 must be led out of the module housing 8 or inserted into it in a fluid-tight manner. This can be done, for example, with the help of a conically sealing compression screw connection inserted into the plate base 22 of the metal housing plate 10, or with other sealing means familiar to the person skilled in the art, for example with the help of a conductor bushing in which each individual conductor 46 or 49 is routed into a selected embedded in material adapted to the conductor insulation is. Since in the present case only a small number of conductors 46 and 49 have to be guided into and out of the module housing 8 in a fluid-tight manner, a conically sealing compression screw connection is sufficient as a sealing means. A typical conical seal compression fitting has a male threaded tube which threads into female threads in the panel base 22 of the metal shell plate 10 and is then secured with a nut threaded onto the male threads; such a mother 50 is in Figure 4a shown on the back 16 of the metal housing plate 10.

Adjacent to and spaced from nut 50, a first round post 52 and a second round post 55 are integrally formed on plate base 22, with each corresponding counterpart 53 and 56 being assigned to rear side 16 of metal housing plate 10. A threaded bore 54 and 57 is formed through each post 52 and 55, as well as through the respective counterpart 53 and 56 and through the plate section located therebetween. Argon can be introduced into the housing interior 9 through one bore 54, and the gas located in the housing interior 9 can simultaneously escape through the other bore 57, while argon (Ar) is being introduced. The composition of the effluent gas can be detected and the Ar introduction can be stopped when the effluent gas consists only of Ar. After the housing interior 9 has been filled with Ar, each bore 54 or 57 is sealed in a pressure-tight manner by screwing a screw 58 or 59 into the threaded bore 54 or 57.

In the metal housing plate 10 there is a flat recess 20 which is open towards the visible side 15 and into which a transparent, essentially flat cover plate 60 is inserted, the flat orientation or extension of which defines a cover plate plane which is aligned therewith. As already explained above, this cover plate 60 consists of a transparent plastic, namely a largely UV-opaque or UV-opaque PMMA material or a UV-stabilized PC material. The cover plate 60 has a rectangular shape with longer sides 61 and 61', with shorter sides 62 and 62' and with rounded corner areas. The orientation or extension of the longer sides 61, 61' defines a cover plate longitudinal direction parallel thereto; the orientation or extent of the shorter sides 62, 62' defines a cover plate transverse direction parallel thereto. The longer sides of the circuit board 40 are aligned parallel to the longitudinal direction of the cover plates. When an LED lamp module 5 according to the invention is used as intended, the longitudinal direction of the cover plates extends in the longitudinal direction of the street lamp 1, and the transverse direction of the cover plates extends in the longitudinal direction of the road surface to be illuminated.

How out Figure 5a As can be seen, the cover plate 60 has an inside 63 adjacent to the metal housing plate 10 and an outside 64 spaced therefrom. A peripheral, uninterrupted side wall 65 is integrally formed on the edge or outer circumference of the cover plate 60 and protrudes from the cover plate 60 perpendicularly with respect to the plane of the cover plate. This side wall 65 has a flat side wall face 66.

• Fig. 5a zeigt in einer erheblich vergrößerten Schnittdarstellung ausschnittsweise die Drei-Nuten-Dichtzone 70 an der Abdeckplatte 60;
• Fig. 5b zeigt in einer erheblich vergrößerten Schnittdarstellung ausschnittsweise die Drei-Flansch-Dichtkontur 30 an der Metall-Gehäuseplatte 12;
• Fig. 5c zeigt Drei-Flansch-Dichtkontur 30 und Drei-Nuten-Dichtzone 70 ineinander gefügt, zusammen mit zusätzlichem dazwischen eingebrachtem Klebstoff, um eine hermetisch dichte Klebeverbindung und Abdichtung zwischen Abdeckplatte 60 und Metall-Gehäuseplatte 10 zu schaffen.

When the cover plate 60 is inserted into the recess 20 on the housing part plate 12, the side wall end face 66 rests on the base 27, and the cover plate 60 and the metal housing plate 10 together delimit a housing interior 9, which is formed in the module housing 8 thanks to the recess 20 . This housing interior 9 can be hermetically sealed using a specific seal and then filled with argon. This particular seal includes a continuous three-flange circumferential seal zone 30 integrally formed on the metal body plate 10 adjacent the plate edge portion 25 thereof, and a complementary continuous three-flange circumferential seal zone 30 integrally formed on the inner surface 62 of the cover plate 60 in the peripheral region thereof -Seal zone 70.

• Figure 5a shows a significantly enlarged sectional view of a detail of the three-groove sealing zone 70 on the cover plate 60;
• Figure 5b shows a significantly enlarged sectional view of a detail of the three-flange sealing contour 30 on the metal housing plate 12;
• Figure 5c shows three-flange sealing contour 30 and three-groove sealing zone 70 joined together, together with additional adhesive introduced in between, in order to create a hermetically tight adhesive connection and seal between cover plate 60 and metal housing plate 10.

Three-flange sealing contour 30

Figure 5b shows a section of the metal housing plate 10 with plate edge section 25, plate edge inner circumference 26 and base 27, which falls in steps towards the plate bottom 22. A section of the graphite foil 23 and the circuit board 40 can be seen on the panel base 22 . The base 27 is integrally formed and extends vertically upwards from the outer flange 32 at a distance from the inner circumference of the plate 26, the central flange 34, which tapers to a point here, at a distance from the outer flange 32 and the inner flange 36 at a distance from the central flange 34. Outer flange 32 and inner flange 36 have a matching rectangular cross-section.

Three groove sealing zone 70

Figure 5a shows a sectional view of an edge section of the cover plate 60 with side wall 65 and a first peripheral flange 68 spaced therefrom, both of which jointly delimit an outer groove 72. Furthermore, a central groove 74 is delimited by this first flange 68 and a second peripheral flange 69 spaced therefrom. Finally, this sealing zone 70 includes an inner groove 76, which is delimited by the second flange 69 and raised surfaces on the inside 62 of the cover plate 60. The outer groove 72 has dimensions such that the outer flange 32 of the three-flange sealing contour 30 fits with play of the metal housing plate 10 can be inserted into this outer groove 72 . The central groove 74 has such a shape and dimensions that the central flange 34 of the three-flange sealing contour 30 on the metal housing plate 10 can be inserted into this central groove 74 with play. The surfaces on the center flange 34 and center groove 74 that are inclined with respect to the plane of the cover plate 60 produce an attempt to adjust the cover plate 60 relative to the metal housing plate 10 a shear stress on the sealant introduced between these surfaces; As is known, the sealing means used here offer a particularly high resistance to such a shearing stress, which prevents the cover plate 60 from being displaced relative to the metal housing plate 10 . The dimensions of the inner groove 76 are such that the inner flange 36 of the three-flange sealing contour 30 on the metal housing plate 10 can be inserted into this inner groove 76 with play.

Figure 5c shows a sectional view on a much larger scale in Figures 5b and 5a indicated and fitted into each other components from three-flange sealing contour 30 and three-groove sealing zone 70. The side wall 65 on the cover plate 60 has a slightly greater length than central flange 74 and inner flange 76; the abutment of sidewall face 66 against base 27 limits the insertion of three flange sealing contour 30 into complementary three flange sealing zone 70 such that a small gap remains between opposing faces; typically the remaining gap may have a gap width of about 0.2 to about 0.5 mm. The initially freshly prepared hardening 2-component acrylate adhesive introduced into the central groove 74 in liquid or plastic form has a gap-filling capacity that depends on its viscosity, migrates in the remaining gap and forms a coherent, hardened adhesive bead 77 between an adhesive bead level 78 in the outer groove 72 and a further adhesive bead level 79 in the inner groove 76. The amount of adhesive introduced is chosen so that both in the outer groove 72 and in the inner groove 76 a level adhesive bead level 78 or 79 parallel to the plane of the board of the entire adhesive bead 77 is formed. Such levels of adhesive strands 78 or 79 parallel to the plane of the board cannot be seen from the outside, so that visible dirt caused by the adhesive introduced is avoided. The migration of the freshly prepared, liquid or plastic adhesive in the entire gap can be promoted by the metal housing plate 10 being held in place during the gluing process and mechanical pressure being exerted on the cover plate 60 at the same time, for example a compressive force of up to 100 Newtons ( N) to bring the side wall face 66 on the cover plate 60 into abutment with the base 27 of the metal housing plate 10.

As a result, after adhesive has been introduced into the central groove 74 and the cover plate 60 has rested against the metal housing plate 10, an uninterrupted, hardened adhesive strand 77 can be formed in the remaining gap between the three-flange sealing contour 30 and the three-groove sealing zone 70 an adhesive line level 78 parallel to the plane of the board in the outer groove 72 to an adhesive line level 79 in the inner groove 76 parallel to the board plane. Such a long adhesive strand 77 provides an insurmountable resistance to the escape of argon from the housing interior 9 and the entry of air and moisture from the external environment into the housing interior 9, so that an extraordinarily high long-term tightness of the module housing 8 is obtained.

Light guide element 80

In accordance with an important aspect of the present invention, cover plate 60 incorporates and integrally molds secondary optics elements therein. Each secondary optics element has a light guide element 80 integrally formed on the inner side 63 of the cover plate 60, to which an integrally formed, coextensive curvature 112 is assigned on the outer side 64 of the cover plate 60; Each individual LED 44 on circuit board 40 is assigned its own light guide element 80, which is used to modify the light distribution pattern of the LED light emitted by the LED. Each light-guiding element 80 forms an additional flat, approximately cuboid layered body 81, which is about 25 mm long, about 20 mm wide and about 3 mm to about 4 mm thick, and which rests in one piece on the cover plate material. "About" is intended here and elsewhere to mean a range of the specified value ranging from 10% smaller to 10% larger; a width of about 20 mm thus includes widths of 18.0 to 22.0 mm.

With Figure 6a is a plan view of a single light guide element 80 on a scale of 1: 4 is shown enlarged. The approximately cuboid laminated body 81 considered here has two longer, parallel, flat sides 82 and 82' and two shorter sides 83 and 83'. The direction of the longer sides 82 and 82' defines a long-side direction and a short-side direction of the light guide member 80 orthogonal thereto. Each stacked body 81 is attached and oriented to the cover plate 60 so that its long-side direction is parallel to the cover plate width direction. The layered body 81 has a flat surface 84 which is aligned parallel and at a distance from the plane of the cover plate and which rests on the printed circuit board 40 on the fully assembled module housing 8 . Quarter-circle-shaped recesses 85 are formed on the layered body 81 in the area of the four corners; in the case of adjacent and adjacent light guide elements 80 (cf. Figure 6d ) Each four recesses 85 together form a round bore 85', through which a screw can be passed, with which the cover plate 60 can be fixed to the metal housing plate 10. In each of the shorter sides 83 and 83' of the layered body 81 is a reentrant triangular recess 86 or 88 which is delimited by straight surfaces 86' and 86" or 88' and 88"; these recesses 86 and 88 have no optical function and only serve to save material.

A first cavity 90 and two second cavities 100 and 106 are formed in the laminated body 81 made of transparent material having a refractive index significantly greater than one; each cavity 90, 100 and 106 is open to the composite surface 84 towards. The first cavity 90 arranged centrally in the layered body 81 has a bell-shaped inner contour 91 with a spherically and concavely curved bottom contour 92 that rises in relation to the plane of the cover plate, opposite a flat base 93, forms the focus 95 of the light-guiding element 80 and serves to accommodate an LED 44. The larger second Cavity 100 is delimited in addition to a flat base surface 101 by a contour 103 which is strongly convexly curved with respect to the focus 95 and is inclined with respect to the plane of the cover plate, the apex 104 of which is directed towards the focus 95 . The smaller second cavity 106 is bounded by a flat base surface 107 and a contour 108 that is moderately convexly curved with respect to the focus 95 and is inclined with respect to the plane of the cover plate. It is chosen such a configuration that on these convexly curved contours 103 and 108, which are inclined relative to the plane of the cover plate, there is a total reflection of LED light rays, which are emitted from the interior of the layered body 81 onto the Surfaces of these contours 103 and 108 meet. This total reflection forces a majority of the LED light to follow a path that is parallel or substantially parallel to the long-side direction of the light guide element 80 .

With Figure 6b is a schematic section along the line AA through the with Figure 6a illustrated light guide element 80 shown. A single light guide element 80 is arranged in an isolated manner on the inside 62 of the cover plate 60 .

With the light-guiding element 80 an asymmetrical distribution, alignment and bundling of the LED light is achieved.

All surfaces on the laminated body 81 that are not aligned parallel to the long-side direction, i.e. the surfaces 86', 86", 88', 88", 93, 103 and 108 are also aligned with an increasing inclination in relation to the plane of the cover plate, so that on these surfaces the incident LED light is deflected and reflected in a direction that is perpendicular or substantially perpendicular to the plane of the cover plate. The LED light directed in this way will then emerge from the module housing 8 on the outside 64 of the cover plate and can be used for lighting purposes.

the Figure 4d Using a schematic, limited sectional view, FIG. This light guide element 80 is assigned a curvature 112 of the same area and integrally formed on the outside 64 of the cover plate. This bulge 112 is delimited in the transverse direction of the cover plate by a moderately concave contour 113 and extends in the longitudinal direction of the cover plate with the same contour. This contour 113 has an apex 114 which, in the example considered here, is at a distance of 3.5 mm from the otherwise flat cover plate surface. On the surface of this bulge 112, the LED light beams that have passed the cover plate 60 are deflected in the direction of the longitudinal center of the road surface to be illuminated.

At least one secondary optical element of the type described above is assigned to each individual LED 44 located on the circuit board 40 . Several secondary optics elements of this type can be formed on the cover plate 60 in isolation and spaced apart from one another. Alternatively, in the case of a number of secondary optics elements on a single cover plate 60, an arrangement can also be selected in which adjacent light-guiding elements 80 touch one another; With Figure 6c such an arrangement of four light guide elements is shown. A row-like arrangement of a plurality of secondary optics elements touching one another has a common curvature 112 on the outside 64 of the cover plate, which extends uninterruptedly in the longitudinal direction of the cover plate. Furthermore, it is possible, independently of the number of LEDs 44 on the circuit board 40, to completely occupy a surface section on the cover plate 60 with the same surface area as the circuit board surface with contacting secondary optical elements of the type described above. The number of secondary optics elements on a cover plate 60 can be greater than the number of LEDs 44 on the associated circuit board 40. Such a cover plate can be manufactured comparatively inexpensively by injection molding and can then be used in different module housings that have a different arrangement of the LEDs the circuit board.

The oblique view Figure 6d shows the inside 63 of a cover plate 60, on which a whole number, for example 30, adjacent light-guiding elements 80 are integrally formed; in this illustration, only three light-guiding elements 80 are delimited with dashed lines and marked as such in isolation; each light guide element 80 corresponds to the representation Figure 6a . The total number of light guide elements 80 is arranged in six rows and five rows; these rows are aligned parallel to the longer sides 61, 61' of the cover plate 60 (cover plate longitudinal direction).

the 7 shows a lighting module 5 according to the invention using an oblique view. Five parallel, uninterrupted, adjacent and touching curvatures 112 can be seen on the outside 64 of the cover plate; each bulge 112 extends equal in area to a series of light guide elements 80, which - like Figure 6d shows - on the inside 63 of the cover plate 60 are formed.

Alternative cover plate 160 with alternative light guide elements 180

With 16a an alternative cover panel 160 is shown having a cover panel longitudinal direction 161 and a cover panel transverse direction 162 orthogonal thereto; in the peripheral area of this cover plate 160 the above-described uninterrupted circumferential three-groove sealing zone 70 is formed. Unless otherwise stated, the alternative cover plate 160 corresponds to the cover plate 60 described above. The cover plate 160 has a total of seven rows that extend in the cover plate transverse direction 162 and five rows that extend in the cover plate longitudinal direction 161 35 alternative light guide elements 180 are formed. This cover plate 160 is intended for a medium-sized street lamp, which is equipped with a rectangular circuit board with dimensions of 17×19 cm on which 35 LEDs are seated, each LED being at least 1.5 cm apart from the next adjacent LED. A single light guide element 180 is marked in the upper left corner of the cover plate 160 with dashed lines. Each light guide element 180 has a light guide element body 181 which forms an integral part of the cover plate 160 . In the longitudinal direction of the cover plates, all seven light guide elements 180 form a homogeneous body without parting line(s); a production-related separation or limitation can be seen between each two adjacent rows of light-conducting elements. The entire alternative cover plate 160 is typically injection molded from high quality PMMA.

With Figure 16b is a plan view of a single insulated light guide element 180 on a scale of 1: 4 shown enlarged, with an arrow B each pointing at a transverse side face 183 of the light guide element 180 and another arrow C pointing at the longitudinal side face 184 of the light guide element 180; each a plan view of these side surfaces 183 and 184 - in the above scale 1: 4 - is with the Figures 16d and 16e shown. Because the light guide member 180 is made of a transparent material, these top views also show structures and boundaries of the light guide member 180 trained cavities to recognize. the Figure 16c shows this in a section along the section line A - A' in Figure 16b available section. With reference to 16f light distributions are explained that can be achieved with an LED lighting module that is equipped with an alternative cover plate 160 .

The individual insulated light guide element 180 forms a flat body 181 with a flat rectangular base surface 182, which has a side length of about 20 mm in the long side direction and a side length of about 25 mm in the short side direction. Here and elsewhere, "approximately" is intended to denote a range of the specified value ranging from 10% smaller to 10% larger; a side length of about 20 mm thus includes side lengths of 18.0 to 22.0 mm. The side surfaces 183 and 184 have a height of about 8 mm. How in particular Figure 16d shows, above this level the light guide element 180 has a slightly contoured top surface 185; in cross-section this contour follows a flat double wave with a central valley 186 extending longitudinally.

The cover plate 160 and thus also each individual light guide element 180 consists here of high-quality, transparent polymethyl methacrylate (PMMA) with a refractive index of 1.49. Three cavities are formed in each light-guiding element body 181, namely a first cavity 190 and two second cavities 194 and 200, all of which are open to the base area 182. The first cavity 190 arranged centrally in the light-guiding element body 181 forms the focus of the light-guiding element 180 and serves to accommodate an LED 44 which dips into this cavity 190 . An arrangement is realized on the finished LED lamp module 5 in which the base area 182 rests on the circuit board 40 and the light-generating LED semiconductor chip is located within the light-guiding element body 181 in its first cavity 190 . The light-guiding element 180, which is also referred to as a lens in the professional world relevant here, has only a small height of approximately 9 to 10 mm, which is why the so-called “flat lens design” (flat-lens design) is implemented according to the invention. The horizontal LED light emerging parallel or nearly parallel and close to the base 182 accounts for about 10% of the total LED light and would be absorbed by the lamp module housing. With the flat lens design, in the light guide element Special cavities are provided, at the boundary surfaces of which a total reflection of the horizontal LED light can take place, so that this light component is forced from the horizontal direction back into the functional direction. On the light guide element 180, the second cavities 194 and 200 form such returning cavities.

• einer großen ebenen Teilkreisfläche 191, die an einem Kreis mit einem Krümmungsradius von etwa 20 mm einen Winkelbereich von etwa 120° abdeckt, und die senkrecht zur Grundfläche 182 ausgerichtet ist;
• einer kleinen ebenen Teilkreisfläche 192, die an einem Kreis mit einem KrümmungsRadius von etwa 10 mm einen Winkelbereich von etwa 120° abdeckt, und die parallel zur großen Teilkreisfläche 191 aus gerichtet und in einem Abstand von etwa 5 mm zu dieser angeordnet ist; und
• von einer anteiligen Kegelstumpfmantelfläche 193, die den Teilkreisumfang der großen Teilkreisfläche 191 mit dem Teilkreisumfang der kleinen Teilkreisfläche 192 verbindet.

The first cavity 190 formed within the light-guiding element body 181 is delimited by

• a large flat pitch circle surface 191 which covers an angular range of approximately 120° on a circle with a radius of curvature of approximately 20 mm and which is oriented perpendicularly to the base surface 182;
• a small flat pitch circle surface 192, which covers an angular range of about 120° on a circle with a radius of curvature of about 10 mm, and which is oriented parallel to the large pitch circle surface 191 and is arranged at a distance of about 5 mm therefrom; and
• by a proportionate truncated cone surface 193, which connects the pitch circle circumference of the large pitch circle surface 191 with the pitch circle circumference of the small pitch circle surface 192.

Adjacent the small pitch area 192 is formed within the light guide body 181, a second cavity, referred to herein as the large retrograde cavity 194; further, adjacent to the large pitch circular area 191 within the light guide body 181, another second cavity is formed, referred to herein as the small receding cavity 200. FIG

• von einer Teilkreisfläche 195, die an einem Kreis mit einem Krümmungsradius von etwa 9 mm einen Winkelbereich von etwa 130° abdeckt, und die parallel und beabstandet zur großen Teilkreisfläche 193 angeordnet ist; und
• von einer anteiligen großen Kegelmantelfläche 196, die an einem Teilkreisumfang der Teilkreisfläche 195 ansetzt und in einer ersten Kegelspitze 197 zusammengeführt ist und endet, die sich an der Grundfläche 182 befindet und dort nur einige wenige Bruchteile eines Millimeters von der kleinen Teilkreisfläche 192 des ersten Hohlraums 190 entfernt ist.

The large receding cavity 194 is confined

• a pitch circle surface 195, which covers an angular range of about 130° on a circle with a radius of curvature of about 9 mm, and which is arranged parallel to and spaced from the large pitch circle surface 193; and
• of a proportional large cone surface 196, which is attached to a pitch circle circumference of the pitch circle surface 195 and is brought together and ends in a first cone tip 197, which is located on the base 182 and there only a few a few fractions of a millimeter from the small pitch surface 192 of the first cavity 190.

• von einer Teilkreisfläche 201, die an einem Kreis mit einem Krümmungsradius von etwa 9 mm einen Winkelbereich von etwa 130° abdeckt, und die parallel und beabstandet zur großen Teilkreisfläche 191 angeordnet ist; und
• von einer anteiligen kleinen Kegelmantelfläche 202, die an einem Teilkreisumfang der Teilkreisfläche 201 ansetzt und in einer zweiten Kegelspitze 203 zusammengeführt ist und endet, die sich an der Grundfläche 182 befindet und dort nur einige wenige Bruchteile eines Millimeters von der großen Teilkreisfläche 191 des ersten Hohlraums 190 entfernt ist.

The small receding cavity 200 is limited

• a pitch circle surface 201, which covers an angular range of about 130° on a circle with a radius of curvature of about 9 mm, and which is arranged parallel to and spaced from the large pitch circle surface 191; and
• of a proportionately small lateral cone surface 202, which starts at a pitch circle circumference of the pitch circle surface 201 and is brought together and ends in a second cone tip 203, which is located on the base surface 182 and there only a few fractions of a millimeter from the large pitch circle surface 191 of the first cavity 190 is removed.

The distance between the partial circular surface 201 on a light-guiding element 180 and the adjacent partial circular surface 195 on the adjacent light-guiding element 180 is approximately 3 mm.

Each light-conducting element 180 and the cavities 190, 194 and 200 formed therein are formed symmetrically to a longitudinal center plane which is aligned with the cutting line AA' and parallel to the longitudinal side direction.

Because each cone apex 197 and 202 is located on the base 182, the adjoining proportionate cone surface 196 or 201 rises obliquely in the longitudinal direction until it has reached the pitch circle circumference on the respective pitch circle 195 or 201. A total reflection of LED light can take place on these rising cone surfaces 196 and 202, which light strikes these cone surfaces on its way through the light-guiding material.

The LED light hits the surface of the cone at an angle of incidence, which here forms an interface between air and PMMA or PC. PMMA has a refractive index of 1.49 and PC has a refractive index of 1.585. Depending on this refractive index, there is a material-specific critical angle, which is 42.17° for PMMA and for PC is 39.13°. If the angle of incidence at which the LED light hits the cone surface is greater than this critical angle, then total reflection of the incident LED light takes place on the cone surface. The LED light reflected in this way will finally emerge from the light-guiding element 180 at the light-guiding element cover surface 185 . With the help of this total reflection, LED light that is parallel or largely parallel to the plane of the board, which is also referred to as "horizontal LED scattered light", can be directed back and forced in a direction in which it emerges from the LED lighting module 5 and is used for lighting purposes can.

There is a desire to keep the overall height of the LED lighting module 5 as small as possible, including the flanges on the back part typically less than 30 mm, and in the case of the medium-sized street light considered here less than 25 mm. With the flat lens design required for this, the proportion of horizontal LED light accounts for up to 10% of the total LED light. With the help of the redirecting cavities 194 and 200 provided according to the invention within the alternative light guide element 180, up to 70% of this horizontal LED scattered light can be redirected, thus saved and additionally used for street lighting. The light yield of an LED lighting module according to the invention can thus be increased by up to 7%.

An alternative LED lamp module 5' can be provided with an alternative cover plate 160, which has a lamp module longitudinal direction and a lamp module transverse direction orthogonal thereto, and on which a total of 35 alternative light guide elements 180 described above are formed in seven rows and five rows; and
all flat partial circular surfaces 191, 192, 195 and 201 of these light guide elements 180 are aligned parallel to the transverse direction of the lamp module. The LED light is intended to emerge from each light-guiding element 180 mainly in the lateral direction in order to achieve an asymmetrical distribution of the illuminance on the illuminated surface.

A street lighting lamp equipped with such an alternative LED lamp module 5' is typically arranged in such a way that the longitudinal direction of the light guide element, the longitudinal direction of the cover plate and thus also the longitudinal direction of the lamp module are aligned perpendicular to the direction of travel of the road to be illuminated. The following results were obtained with the alternative LED lighting module 5' described here:
The light guide element 180 consists of PMMA, with a refractive index of 1.49; the surfaces of cavities 190, 194 and 200 are finely machined and have high smoothness (rough surfaces would scatter light in different directions). A total reflection of LED light can take place on the conical surfaces 196 and 202 delimiting the redirecting cavities 194 and 200, which light hits this conical surface on its way through the light-guiding element material if its angle of incidence is greater than the critical angle of 42.17°.

For the measurements below, an LED lamp module according to the invention was used, which contains 24 LEDs (light wattage 72 W), each of which is associated with an alternative light guide element 180 that delivers a luminous flux of around 8750 lm and that is attached to a street light. which in turn is attached to a whip pole at a height of 10 m above the roadway. This street light is intended to illuminate a typical street with a lane width of 6 m (two directions of travel), which is followed by a 2.5 m wide parking zone and a 2.4 m wide footpath. With the usual measurement and evaluation method, the illuminance is determined on a circular, flat surface at a number of measuring points, which are identified by their polar coordinates. For the C0 - C180 plane (middle of the lane and parallel to the direction of the lane) and for the C90 - C270 plane, the results obtained in this way are included 16f . shown; the range obtained for the C0 - C180 plane is shown with a solid line; the range obtained for the C90 - C270 plane is shown with a dashed line. The delimited areas are a measure of the luminance levels obtained in the respective direction. Obviously, a very different luminance distribution is obtained, which is adapted to the respective needs; the lane is on a Long area is sufficiently and evenly illuminated, so that a distance of 40 m between two whip masts, each with a street lamp, is possible. The illuminance values required by DIN EN 13 201 for various areas are also met:
Road, selected lighting class ME4a, measured on a grid with 14 × 6 measuring points: roadway luminance _Lm (cd/m2 ⁾ U ₀ U ₁ TI (%) SR calculated from measured values: 0.55 0.50 0.70 13 0.85 required by the standard: > 0.40 > 0.40 > 0.60 < 15 > 0.50
Parking zone 1, length 40 m, width 2.5 m, selected lighting class CE5, measured on a grid with 14 × 3 measuring points medium luminance E _av (Ix) U0 calculated from measured values: 6.08 0.56 required by the standard: > 6.00 > 0.40
Footpath 1, length 40 m, width 2.4 m, selected lighting class S5, measured on a grid with 14 × 6 measuring points: medium luminance E _av (Ix) Emin (Ix) calculated from measured values: 3.77 2.60 required by the standard: > 3.00 > 0.60

Hermetically sealed adhesive connection

A hermetically sealed adhesive bond is created between the metal housing plate 10 and the transparent cover plate 60 using an adhesive which, both during the reaction of the two adhesive components and later in the cured state, poses the risk of releasing, outgassing or evaporating incompatible, volatile, organic Compounds, so-called VOCs, minimal is. As is well known, the simple 1-component cyanoacrylate adhesives that are often used, such as "Superglue", are less suitable here. According to the invention, a selected 2-component acrylate adhesive that hardens at room temperature and in which this risk is minimal is used here.

According to the invention, the hermetically sealed adhesive connection between cover plate 60 and metal housing plate 10 is particularly preferably produced using a 2-component acrylate adhesive based on methyl methacrylate, which is cured by peroxide-induced radical polycondensation. The peroxide-induced radical polycondensation provides a fully reacted, cured product that emits no volatile organic compounds or components (VOCs). Typically, one part by volume of peroxide component B is used for ten parts by volume of methyl methacrylate component A.

• je eine Kartusche für die Komponente A (400 ml) und die Komponente B (50 ml);
• einen Statikmischer und
• eine, an eine Druckluftquelle angeschlossene 2-Komponenten-Pistole.

After about 4 to 10 minutes of mixing the two components A and B (pot life), the adhesive is ready for use. Mixing and application can be carried out at room temperature (approx. 25 °C). Mixing and application can be done using a portable applicator that includes:

• one cartridge each for component A (400 ml) and component B (50 ml);
• a static mixer and
• a 2-component gun connected to a source of compressed air.

The prepared adhesive mixture is introduced into the central groove 74 of the three-groove sealing zone 70 on the cover plate 60 with the aid of the 2-component pistol. The adhesive mixture adheres to the groove surfaces. The cover plate 60 provided with adhesive mixture is immediately placed on the metal housing plate 10 in such a way that its three-flange sealing contour 30 penetrates into the three-groove sealing zone 70 on the cover plate 60. Subsequently—with the housing plate 10 held in place—a considerable compressive force, for example up to 100 N, can be exerted on the cover plate 60 in order to achieve its final arrangement on the housing plate 10 .

A quantity of 2-component acrylate adhesive is introduced into the central groove 74 so that the adhesive mixture introduced can form an uninterrupted adhesive bead 77, which extends from a first adhesive bead level 78 in the outer groove 72 to a second adhesive bead level 79 in the inner groove 76. The entire arrangement is then left to rest for at least 12 hours in order to achieve sufficient strength of the adhesive bond for further processing. Thereafter, the LED lighting module 5 obtained in this way can be subjected to further processing.

As the next step, a leak test is carried out on the LED lamp module 5 that has been completed to this point. As stated above, a first round post 52 and a second round post 55 are integrally formed on the plate bottom 22 of the metal housing plate 10, each of which has a corresponding counterpart 53 and 56 associated with it on the rear side 16 of the housing plate 10; through each post 52 and 55, as well as through the respective counterpart 53 and 56 and through the plate section located between them, a bore 54 and 57 provided with an internal thread is guided. An air pressure gauge is connected to one bore 54 . A suction pump is connected to the other bore 57, with which the air pressure in the interior 9 of the module housing 8 is lowered to a value of 100 millibars (mbar) or less. Preferably, before this vacuum treatment, the LED lamp module 5 is heated to an elevated temperature, for example to about 50 to 80° C., and the application of vacuum is continuously carried out at this elevated temperature for at least 20 minutes. With this special vacuum treatment, even stubbornly adhering VOCs can be largely removed from the interior 9 of the module housing 8 . The connection to the suction pump is interrupted and this hole is sealed pressure-tight. Then, with the help of the air pressure gauge connected to the other hole 57, it is checked whether the negative pressure set in the interior 9 remains constant for at least 30 seconds. A noticeable drop in pressure within this period of time would be an exclusion criterion. An LED light module that is found to be good in this vacuum test is fed to the next work step.

In the course of this step, the lamp module interior 9 is filled with argon (Ar). Ar is preferably used which has a purity greater than 99.99%, for example a purity of 99.996%. Such Ar can be provided from commercially available compressed gas cylinders. Suitable Ar compressed gas bottles can be obtained, for example, from KRAISS & FRIZ, 70190 Stuttgart, Germany. A probe downstream of a gas pressure reducing valve is connected to one bore 54 in order to introduce Ar into the interior 9 of the lamp module. A gas analyzer is connected to the other hole 57 and analyzes the composition of the gas emerging from the lamp module interior 9 . A gas analyzer marketed by Helantec GmbH, 76646 Bruchsal, Germany under the trade name GAS FILLING STATION “MINI” is well suited for this purpose. With this device, the composition of the escaping gas can be determined with an accuracy of more than 2%. After the gas analyzer indicates that the exiting gas consists of 100% Ar, the gas exchange is terminated and the two bores 54 and 57 are sealed pressure-tight with the aid of the screws 58 and 58', respectively. For this purpose, one screw 58 or 58' wrapped with Teflon tape can be screwed into the associated bore 54 or 57 and secured there. The LED lighting module filled with the desired Ar gas filling is fed to the next work step.

In this final work step, the function of the electronics and the light generation caused by the LEDs as well as the desired light propagation are checked. If the tested LED lighting module meets all specified requirements, a test certificate with the item number and the time of testing is issued and attached to the tested LED lighting module.

EXPERIMENT FOR THE ACCELERATED TEST OF THE LONG-TERM TIGHTNESS OF THE MODULE HOUSING

The space between the two panes of a double pane window assembly is often filled with argon or krypton to improve the thermal insulation of such window assemblies. Experience has shown that it escapes Argon from such window assemblies re-enters the enclosed space between the two panes three times faster or more faster than nitrogen and oxygen from the ambient air. Over time, a negative pressure builds up in this closed space, which can lead to implosion. There is therefore a need to determine the argon content in such closed double pane window assemblies without destroying the assembly and/or removing and analyzing gas from the enclosed space. the authors Alex Sergeyev and Jacek Borysov with their contribution "Nondestructive Method of Measuring Relative Concentration of Gases (eg Argon) in Double-Pane Windows", published in "Sensors and Materials", Vol. 20, No. 3 (2008), pages 123- 130 , MYU Tokyo described a method to solve this problem. Essentially, it is intended to ignite and operate a DC arc within the gas atmosphere in the closed space between the two panes, and to analyze the light generated by this arc. This light has emissions characteristic of nitrogen between 330 and 420 nm and emission characteristic of argon at 750.4 nm. The relative ratio of the proportions of air and argon in the gas atmosphere between the two panes can be deduced from the relative ratio of the measured absorptions of these emissions. The authors state that this method can determine the argon content with an accuracy of approximately 5% at moderate to high argon concentrations in air.

As described above, three identical module housings I, II and III are manufactured and provided. In each module housing I, II and III, a bracket is attached to the base of the metal housing plate, which holds two electrodes in such a way that when a DC voltage of between 2 and 5 kV is applied between the electrodes, an arc is ignited and can be operated. Voltage and current are supplied via a multi-core cable which is sealed to the housing with the aid of a standard, conically sealing compression fitting. The sensor of a spectrometer can be attached to the transparent cover plate of each module housing I, II and III Detects and evaluates the radiation formed in the gas atmosphere and prints out and saves a corresponding spectrum.

A spectrometer sold by Medialas Electronics GmbH, 72336 Balingen, DE under the trade name "Spectrometer USP-1" is well suited here, and has a measuring range of 200 to 1200 nm. The interior of module housings I and II is filled with 100% Ar. The interior of the module housing III is filled with different gas compositions for calibration purposes, and comparison spectra are generated from them; The following gas compositions are measured in detail: 100% Ar, 90% Ar + 10% air, 80% Ar + 20% air to ... 10% Ar and 90% air and 100% air. In 8 the spectra thus obtained are shown for the gas compositions 100% Ar, 70% Ar+30% air, 50% Ar+50% air, 30% Ar+70% air and 100% air.

The actual experiment started in January 2017 and ended in November 2017. During this period of time, the module housing I, which is filled with 100% Ar, is kept at a constant temperature of 25 °C and below the ambient air pressure. The arc is ignited at least once a week and a spectrum of the current gas composition is produced and saved. This is considered a reference treatment for typical aging under ambient conditions.

Furthermore, a drying oven is provided in which a closable pressure chamber is set up. The module housing II filled with 100% Ar is placed in this pressure chamber and kept there for 23 hours per day at 50 °C and under an air pressure that is reduced by 100 mbar (millibar) compared to the ambient air pressure. During the 24th hour, the pressure chamber is opened, the module housing II is exposed to the ambient air pressure, the arc is ignited and a spectrum of the current gas composition is produced and saved. This type of treatment is classified as an accelerated aging treatment.

It is found that after one week of accelerated aging treatment, the gas composition formed in module housing II has a spectrum which agrees with the spectrum obtained from the gas composition in module housing I after 23 weeks of typical aging under ambient conditions. From this it is concluded that the accelerated aging treatment under the conditions practiced here has an "acceleration factor" of 23. Consequently, after 46 weeks of accelerated aging treatment, the gas mixture formed in the module housing II should have a composition which, after conventional aging under ambient conditions, is only obtained after 1058 weeks; that is a period of 20.7 years. A comparison with a comparative spectrum confirms that the gas composition formed in module housing II after 46 weeks of accelerated aging treatment still contains at least 58% of the originally filled argon (Ar). the 9 Figure 12 shows some spectra obtained from the gas composition formed in Module Housing II at specified times of accelerated aging treatment.

The test results obtained in this way lead us to expect that the argon content within the atmosphere in a specific module housing manufactured as described over the course of 20 years under normal ambient conditions in accordance with the 10 shown curve decreases and is replaced by ambient air.

In any case, the above test confirms the expectation that the LEDs in the module housing manufactured according to the invention of an LED lighting module according to the invention and producing white light can be operated under a protective atmosphere for a service life of at least 20 years.

Claims (21)

1. LED lighting module (5)

   comprising a two-part module housing (8)

   consisting of a metal housing plate (10) and of a transparent cover plate (60, 160), wherein a circumferential side wall (65) is integrally formed on each of the metal housing plate (10) and/or on the cover plate (60, 160), such that the metal housing plate (10), one side wall (65) or both side walls and the cover plate (60, 160) together delimit a hermetically sealed housing interior (9), in which a circuit board (40) is provided, on which a number of spaced-apart LEDs (40) are seated; and

   each individual LED (44) is assigned a secondary optical element, which captures the LED light generated by a given LED (44) and directs and focuses this LED light in accordance to a predetermined lighting purpose,

   wherein

   - the metal housing plate (10) consists of a light metal suitable for housing or of a Zamak alloy;

   - the cover plate (60, 160) consists of a largely UV-impermeable or of a UV-impermeable PMMA material or of a UV-stabilized PC material;

   - each secondary optical element has a light-guiding element (80) or an alternative light-guiding element (180) consisting of the cover plate material and integrally formed with the cover plate (60, 160); and

   - a hermetically sealed bond is provided between the metal housing plate (10) and the cover plate (60, 160)

   characterized in that

   - each light-guiding element (80, 180) is integrally formed with the cover plate (60, 160) at the inner side (63) thereof adjacent to the printed circuit board (40);

   - the hermetically sealed bond between the metal housing plate (10) and the cover plate (60, 160) is an adhesive means bond obtained with the aid of a two-component acrylate adhesive curable at room temperature;

   - an argon-containing atmosphere prevails inside the housing interior (9); and

   - the module housing (8) has such a long-term tightness, which ensures that after performing a 46 weeks lasting accelerated ageing treatment, during which the LED lighting module (5) is always kept at approximately 50°C and is further kept for one hour per day under ambient air pressure and for further 23 hours under an air pressure reduced by 100 mbar compared to the ambient air pressure,

   the atmosphere within the housing interior (9) still consists in an amount of at least 58 % by volume of the originally introduced 100 % argon-filling.
2. The LED-lighting module according to claim 1,

   characterized in that

   the light-guiding element (80) provided at the cover plate (60) forms an additional flat, approximately cuboid-shaped layered body (81), comprising

   - a length of about 25 mm,

   - a width of about 20 mm,

   - a thickness of about 3 mm to about 4 mm, and

   - having a layered body surface (84); and

   a first cavity (90) and two second cavities (100) and (106) are formed within said layered body (81), all of which are open towards the layered body surface (84).
3. The LED-lighting module according to claim 2,
   characterized in that

   - the first cavity (90) is arranged in the center of the light-guiding element (80), forming a focus (95) of the light-guiding element (80) and serving to receive an LED (44);

   - the larger second cavity (100) has a contour (103) which is strong convexly curved with respect to the focus (95) and which is inclined relative to the cover plate plane, and said contour (103) having an apex (104) which is directed towards the focus (95);

   - the smaller second cavity (106) has a contour (108) which is moderately convexly curved with respect to the focus (95) and which is inclined relative to the cover plate plane, and said contour (108) having an apex (109) which is directed towards the focus (95); and

   - a total reflection of the LED light beams emanating from the interior of the layered body (81) and impinging on these surfaces of the contours (103) and (108) occurs at these surfaces.
4. The LED-lighting module according to claim 2 or claim 3,

   characterized in that

   the layered body (81) has two longer parallel planar sides (82 and 82'), the direction and extension thereof define a long-side direction and a short-side direction orthogonal thereto of the light-guiding element (80); and

   a coextensive, convex bulge (112) consisting of the cover plate material is integrally attached at the outer side (64) of the cover plate (60)

   over each layered body (81), said bulge (112) has an apex line (114) directed parallel to the short-side direction of the light-guiding element (80).
5. The LED-lighting module according to one of claims 1 to 4,
   characterized in that
   the LED lighting module is suited to provide a roadway luminance which meets at least the requirements of the M lighting classes ME5 and ME6 according to DIN EN 13201-2 on dry and wet road surfaces.
6. The LED-lighting module according to one of claims 1 to 5,
   characterized in that

   - the LED lighting module (5) may be attached via the rear side of its metal housing plate (10) to the back part (3) of a street lamp (1);

   - a number of flanges (17 and 17') is integrally arranged in pairs at the rear side (16) of the metal housing plate (10) and thus forming pairs of flanges each having outer flanks (18 and 18'); and

   - when attaching the LED lighting module (5) at the back part (3) of the street lamp (1), each pair of flanges enters a complimentary groove recessed there and having such dimensions that a contact pressure between the groove flanks and the outer flanks (18 and 18') of each entering pair of flanges will be generated.
7. The LED-lighting module according to one of claims 1 to 6,
   characterized in that

   - a stepped, circumferential and uninterrupted base (27) is integrally attached to the inner circumference (26) of the metal housing plate (10), and an upright, circumferential and uninterrupted three-flange sealing contour (30) is integrally attached to said base (27), and this three-flange sealing contour (30) comprises an outer flange (32), a central flange (34) spaced apart therefrom and an inner flange (36) spaced apart therefrom, and each flange (32, 34 and 36) is arranged adjacent and spaced to the inner circumference (26) of the metal housing plate (10);

   - further, a circumferential and uninterrupted three-groove sealing zone (70) is formed at the cover plate (60), adjacent and spaced to a side wall (62) of a cover plate inner side (63), and this three-groove sealing zone (70) comprises an outer groove (72), a central groove (74) and an inner groove (76), and this three-groove sealing zone (70) is formed complementary to the three-flange sealing contour (30) on the metal housing plate (10); and

   - after introducing liquid or plastic adhesive into the central groove (74) and after attachment of the cover plate (60) at the metal housing plate (10), an uninterrupted slit is formed between the three-flange sealing contour (30) and the three-groove sealing zone (70), and this slit is filled with an uninterrupted adhesive strand (77).
8. The LED-lighting module according to claim 7,
   characterized in that
   the adhesive strand (77) extends uninterrupted from a first adhesive strand level (78) arranged parallel to the cover plate plane within the outer groove (72) up to a second adhesive strand level (79) arranged parallel to the cover plate plane within the inner groove (76).
9. The LED-lighting module according to one of claims 1 to 8,

   characterized in that

   a number of medium-power LEDs which are operated with an average power consumption of approximately 3 watts (W) sit on the circuit board (40); and

   the circuit board (40) has dimensions such at least a circuit board area of 5 to 9 cm² is available for each medium-power LED.
10. The LED-lighting module according to one of claims 1 to 9,

    characterized in that

    the circuit board (40) is placed within the housing interior (9) upon a plate floor (22) of the metal housing plate (10); and

    a graphite foil (23) is inserted between said plate floor (22) and the circuit board (40).
11. A method of manufacturing the LED lighting module (5) according to one of claims 1 to 10.
12. The method according to claim 11,
    characterized in that
    as 2-component acrylate adhesive a 2-component acrylate adhesive based on methacrylic acid methacrylate is used, which is cured by peroxide-induced radical polycondensation.
13. The method according to claim 11 or claim 12,
    characterized in that

    - an upright, circumferential and uninterrupted three-flange sealing contour (30) comprising an outer flange (32), a central flange (34) spaced apart therefrom and an inner flange (36) spaced apart therefrom is integrally formed at the metal housing plate (10 in the circumferential area thereof and adjacent and spaced apart to the inner circumference (26) thereof;

    - further, a circumferential and uninterrupted three-groove sealing zone (70) which is complementary to the three-flange sealing contour (30) and which has an outer groove (72), a central groove (74) and an inner groove (76) is formed at the cover plate (60, 160) in the circumferential area and at the inner side (65) thereof, adjacent and spaced to a side wall (62) thereof; and

    - such an amount of 2-component acrylate adhesive is introduced into said central groove (74), that

    - after introducing liquid or plastic adhesive into the central groove (74) and after attachment of the cover plate (60) at the metal housing plate (10), an uninterrupted slit is formed between the three-flange sealing contour (30) and the three-groove sealing zone (70), and this slit is filled with an uninterrupted adhesive strand (77), which extends uninterrupted from a first adhesive strand level (78) arranged parallel to the cover plate plane within the outer groove (72) up to a second adhesive strand level (79) arranged parallel to the cover plate plane within the inner groove (76).
14. The method according to one of claims 11 to 13,
    characterized in that
    after preparing and curing said adhesive bond at the module housing (8), the LED lighting module (5) has been completed to this extent, a leak test is carried out, for which purpose the gas pressure in the housing interior (9) is lowered to a value of 100 mbar or less.
15. The method according to claim 14,
    characterized in that
    before and during said leak test, the module housing (8) is heated to a temperature of from 50 to 80 °C.
16. The LED-lighting module according to claim 1,
    characterized in that
    the alternative light-guiding element (180) comprises a flat body (181) having

    - a planar rectangular base surface (182) with side lengths of about 20 mm x about 25 mm;

    - side surfaces (183) with a height of about 8 mm; and

    - in this body (181) a first cavity (190) and two second cavities (194 and 200) are formed, all of which are open towards said base surface (182).
17. The LED-lighting module according to claim 16,
    characterized in that
    the first cavity (190) is delimited by

    - a large partial circle surface (191) which covers an angular area of about 140° on a circle having a curvature radius of 12 mm;

    - a small partial circle surface (192) which covers an angular area of about 140° on a circle having a curvature radius of about 8 mm and which is arranged parallel and at a distance from the large partial circle surface (191); and by

    - a truncated cone surface (193) which connects the partial circle circumference of the large partial circle surface (191) with the partial circle circumference of the small partial circle surface (192).
18. The LED-lighting module according to claim 16 or claim 17,
    characterized in that
    the second cavity (194) is delimited by

    - a partial circle surface (195) which covers an angular area of about 140° on a circle having a curvature radius of about 9 mm and which is arranged parallel and at a distance from the large partial circle surface (191); and by

    - a proportionately large cone surface (196), which starts at a partial circle circumference of the partial circle surface (195) and which is brought together and ends in a first cone tip (197), which is located on the base surface (182) and there only a few fractions of a millimeter remote from the small partial circle surface (192) of the first cavity (190).
19. The LED-lighting module according to one of claims 16 to 18,
    characterized in that
    the second cavity (200) is delimited by

    - a partial circle surface (201) which covers an angular area of about 140° on a circle having a curvature radius of about 9 mm and which is arranged parallel and at a distance from the large partial circle surface (191); and by

    - a proportionately small cone surface (202), which starts at a partial circle circumference of the partial circle surface (201) and which is brought together and ends in a second cone tip (202), which is located on the base surface (182) and there only a few fractions of a millimeter remote from the large partial circle surface (191) of the first cavity (190).
20. The LED-lighting module according to one of claims 16 to 19,

    characterized in that

    the LED lighting module (5) is provided with an alternative cover plate (160) having a lighting module longitudinal direction and a lighting module transverse direction, orthogonal thereto; and

    wherein a total of 35 alternative light-guiding elements (180) are arranged in seven lines and five rows; and

    all planar partial circle surfaces (191, 192, 195 and 201) of these light-guiding elements (180) are aligned parallel to said lighting module transverse direction.
21. The LED-lighting module according to claim 20,
    characterized in that
    with the light-guiding element (180) up to 70 % of the horizontal scattered LED light can be used for illumination purposes, whereby the light yield or efficiency of the LED lighting module can be increased by up to 7 %.

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