Lighting fixture

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention has a housing that defines an internal space, in which at least one light source composed of light emitting diodes (LEDs) and optical means for guiding light generated from these LEDs to the outside of the housing. It is about the lighting equipment to be housed.

【0002】

[Conventional technology]

Such luminaires are described in International Publication No. WO 98/33007. This luminaire is designed for street lights and uses the light generated by LEDs. Optical guidance means are used to focus the lumen intensity (luminosity) generated by the LED on the beam on the one hand and to ensure that the beam is directional on the other hand.

【0003】

The light emission characteristics of LEDs have a special shape. Optical means that operate by optical principles have a shape arrangement (geometry) that can be used to provide optimum performance if the optical means takes an accurate and constant position with respect to the emission characteristics of the LED. Since luminaires are first transported and then installed, robustness must be ensured in the attachment of optical means to the LED if the illuminant maintains the properties required by the manufacturer.

【0004】

[Problems to be Solved by the Invention]

In WO98 / 33007, the LED is fixed inside the optical means, and this optical means is fixed to the housing. Delicate handling of LEDs is required to realize this structure. However, LEDs are extremely sensitive to mechanical handling, and their lifespan and light emission performance depend in particular on their delicate attention to proper handling during installation inside the above-mentioned luminaires. Among other things, LEDs have a fragile dome where no significant force is allowed. Delicate installation work such as the luminaires proposed in WO 98/33007 should be avoided. Moreover, this installation is time consuming and costly in the automation work.

【0005】

Therefore, an object of the present invention is to obtain a luminaire that greatly reduces the problem of attaching optical means to the LEDs inside the luminaire.

【0006】

[Means for solving problems]

In order to achieve this object, the luminaire of the present invention is characterized in that the LED is attached to a support connected to a housing and the optical means is held between the housing and a holding element connected to the LED support. To do.

【0007】

According to this configuration of the present invention, this attachment is performed by arranging the optical means on the support of the LED and using a holding element that is connected to the housing and fixed in position. This mounting has the advantage that the LEDs are pre-installed on the support, eliminating the need for delicate handling of the LEDs and thus being easy to automate.

【0008】

In a preferred embodiment of the present invention, the optical means is elastically held between the holding element connected to the housing and the LED support via the elastic holding means. This elastic holding means, which operates in conjunction with a holding element connected to the housing, exerts pressure on the optical means. As a result, the optical means applies pressure to the LED support. Any mechanical play that exists between the retaining element and the optical means connected to the housing and between the optical means and the LED support is eliminated, thereby allowing the optical means to the LED support. Eliminate relative movement. The shape of the optical means and the shape of the LED support ensure a precise and constant position for optimum performance by contact between the optical means and the LED support when pressure is applied. It is preferable to adapt to.

【0009】

In a preferred embodiment of the present invention, the elastic holding means of the optical means is in the form of a block of elastic material, and the block is placed at a predetermined position to be compressed between the holding means connected to the housing and the optical means. To do. This elastic material can be, in particular, one of many foam type materials. This method has the advantage of being easy to implement and allowing the strength of the pressure exerted by the optical means on the LED support to be controlled by selecting the properties of the elastic material used.

【0010】

In a preferred embodiment of the present invention, a material having a low adhesive coefficient is arranged between the optical means and the holding element connected to the housing. This material provides contact between the optical means and either the retaining element or the elastic retaining means of the optical means. The action of this material with a low adhesive coefficient, such as polyethylene, only makes contact between the optical means and either the holding element or the elastic holding means connected to the housing, facilitating relative translational movement. The translational movement of the holding element connected to the housing or the LED support of the elastic holding means to the housing to which the LED support is fixed is when the optical means and either the holding element of the optical means or the elastic holding means are fixed. In practice, translational movement with optical means occurs, in which case the optical means shift from the optimum performance position for the light emission characteristics of the LED. This translational movement, which results in relative movement at the contact level between objects, may be the result of external mechanical stress caused by the difference in thermal expansion of different material brackets. Differences in expansion cause objects to form objects of different materials and become extremely hot, causing relative movement between objects in an environment where movement is not negligible.

【0011】

In a preferred embodiment of the present invention, the holding element connected to the housing is connected to the housing by an adhesive means. This method eliminates the need to use screws. Although screws are customarily used in the field of luminaires, they cause problems related to differences in expansion when the materials to be joined to each other are different, which is common in the types of luminaires mentioned above. .. The use of adhesive means has the advantage that the luminaire can be significantly smaller than those that use screws. That is, the bonding means requires only a certain surface area and does not require a large volume of the material.

【0012】

In a preferred embodiment of the present invention, the adhesive means is an adhesive tape.

【0013】

Further, in a preferred embodiment of the present invention, the holding element connected to the housing is a plate that transmits light. This configuration is suitable when applied when the light transmissive plate is placed on the optical means. That is, in order to satisfy the two functions of protecting the fragile optical means and holding the optical means in a predetermined position.

【0014】

BEST MODE FOR CARRYING OUT THE INVENTION

Next, a preferred embodiment of the present invention will be described with reference to the drawings.

【0015】

The luminaire according to the present invention has a housing 1 that houses a light emitting diode, that is, a light source composed of LEDs 2, and the LEDs 2 are attached to a support 3 fixed to the housing 1. The LED support 3 can be, for example, a printed circuit board, and the support 3 is fixed by, for example, an adhesive means. The use of an adhesive means, for example, an adhesive tape, has the advantage of contributing to proper heat dissipation. In fact, the bonding means exhibits good thermal conductivity properties and maximizes the contact area between the support 3 and the housing 1. In the illustrated embodiment, the support 3 is planar, but the support 3 having another shape is not excluded.

【0016】

In the illustrated embodiment, as an optical means, a collimator 4 formed of a heat-resistant material such as polymethylmethacrylate (PMMA) that transmits light is provided. This optical means is formed by a "full body" collimator 4, but can also be formed by, for example, a conical concave reflector. The collimator 4 has a symmetrical side surface 5 based on a parabolic or conical rotating body, a planar front surface 6 (in the illustrated embodiment), and a bottom surface 7 opposite the front surface 6. In the illustrated embodiment, the bottom surface 7 is flat, but other shapes are not excluded. The light generated by the LED 2 is focused as a beam by the side surface 5 of the collimator 4. The beam generated in this way is a directional light beam forming parallel rays. The light beam is emitted from the collimator 4 at the front surface 6, and the direction of the light beam is orthogonal to the plane defined by the front surface 6. The emission characteristic of the optical system including the LED 2 and the collimator 4 has the maximum emission direction, and this maximum emission direction is orthogonal to the plane defined by the front surface 6 of the collimator 4 in the case of the illustrated embodiment. [0017]

The collimator 4 further provides a cavity 8 on the bottom surface 7 for accommodating the LED 2. The collimator 4 is located above the LED 2. Since the LED is susceptible to the pressure applied to the dome 9, the contact between the LED 2 and the collimator 4 is minimized, the inside dimension of the cavity 8 is made larger, and the bottom surface 7 is placed on the support 3 to which the LED 2 is attached. Let me do it.

【0018】

The optimum illumination characteristics of the collimator 4, that is, the control of the beam configuration and the beam output, are obtained by precisely positioning the collimator 4 with respect to the light emission characteristics of the LED 2. If the bottom surface 7 of the collimator 4 is shifted sideways with respect to the LED 2 by 4% or more of the LED diameter, an efficiency loss of 10% occurs. Therefore, the manufacturing tolerance of the bottom surface 7 of the collimator 4 and the dimensional tolerance of the cavity 8 are calculated so that the lateral translation of the collimator 4 with respect to the LED 2 is sufficiently small to guarantee good lighting characteristics at the output of the collimator 4. To do. These dimensions take into account that no large lateral stress is applied to LED2.

【0019】

By arranging the collimator 4 on the support 3 of the LED 2, the initial positioning is ensured, and this initial positioning is maintained by the holding element connected to the housing 1. In the illustrated embodiment, the holding element is a light transmissive plate 10. The light-transmitting plate 10 is placed on the collimator 4 and the block of the elastic material 11 is compressed. The plate 10 is connected to the housing 1 by the double-sided adhesive tape 12. Since the collimator 4 is a fragile optical instrument, the light transmissive plate 10 protects the collimator from external adverse effects that damage it or impair its optical performance. The use of adhesive means such as adhesive tape 12 also helps to improve the sealing performance of the luminaire. In principle, housing 1 and plate 10 are made of different materials and therefore undergo different expansions, so using an adhesive means such as adhesive tape 12 that allows a good choice of shear resistance can be used with housing 1 and plate 10. Gives a solution that allows relative movement of.

【0020】

In the illustrated embodiment, the block of elastic material 11 is placed on the front surface 6 of the collimator 4. The elastic material can be selected from different densities, different shapes and multiple foam materials as a function of the strength of the pressure desired to be applied to the collimator 4 to keep the collimator 4 in place. In one embodiment, for example, a block of elastic material 11 is woven from a vinyl foam exhibiting single-sided adhesion to a density of 225 kg / m.³ , 6 mm thick and 3 mm wide. Various changes are possible with respect to the elastic retention of the optical means and the relative positioning of the elastic retention means with respect to other elements of the luminaire. For example, the use of springs is conceivable, and other methods may be considered for the arrangement of elastic holding means between the LED support and the surface forming portion of the housing itself, for example, the holding means constituting the holding element connected to the housing. Be done.

【0021】

The collimator 4 is configured to have optimum efficiency when the contact of the collimator 4 with the support 3 of the LED 2 is flat. Rotational motion around a number of axes orthogonal to the direction of the maximum emission of the light emission characteristics of the optical system consisting of the LED 2 and the collimator 4 impairs the planar contact between the collimator 4 and the support 3 of the LED 2. .. In the case of the illustrated embodiment, rotating the collimator more than 3 ° around these axes results in a loss of 10% of the maximum amount of light. Such rotational movement causes play between various elements such as the LED support 3, the collimator 4, and the plate 10 that transmits light in a direction that approximates the maximum emission direction of the optical system consisting of the LED 2 and the collimator 4. Occurs only in certain cases. Elastic material 11, i.e., the elastic retaining means applies pressure to the collimator 4 to ensure planar contact with the LED support 3. In this way, the collimator's elastic holding means can eliminate play and thus prevent rotation.

【0022】

A material with a low adhesive coefficient, for example, polyethylene strips 13 is inserted between the elastic holding means composed of blocks of the elastic material 11 and the optical means composed of the collimator 4, and between various elements made of different materials. Allows translational movements that occur with different expansions of. In particular, the pressure exerted by the block of elastic material 11 on the collimator 4 prevents such translational movements that can occur in the absence of a material with a low adhesive coefficient, and also a light-transmitting plate 10 connected to the housing. Guarantee the movement of the collimator along. The presence of polyethylene, i.e., low-adhesion coefficient strip 13, separates the translational motion of the elastic material 11 from the collimator 4, thus avoiding the movement of the collimator 4 with respect to the support 3 of the LED 2.

【0023】

The housing may be made of a heat conductive material, for example, aluminum on which an anodized film is formed, and a corrugated surface 14 is provided on the outer surface. LED2 generates heat during operation. Temperature control is required to obtain optimum LED performance, mainly in terms of luminous flux lumens. The heat generated by LED2 must be eliminated. The heat conductive material of the housing transfers heat to the outside, and the corrugated surface improves the heat dissipation effect.

【0024】

FIG. 2 shows the inside of a luminaire having a plurality of LEDs and fixing optical means by the method of the present invention. Increasing the number of LEDs increases the length of the luminaire, which in turn increases the relative movement caused by different expansions between different materials. The present invention is particularly advantageous for application in such cases.

【0025】

The support 21 carrying a large number of LEDs 22 is fixed to the housing 20. A single collimator 23 is aligned and placed on the support 21 of each LED 22. In a special embodiment of the present invention, as an alternative, several collimators 23 are arranged on the support 21 so that each collimator is aligned with one LED 22. A light transmissive plate 24 is placed on the top surface of the set of collimators 23 to compress two strips 25a, 25b of elastic material. The plate 24 is connected to the housing 20 by two strips 26a, 26b of double-sided adhesive tape. Polyethylene, i.e., two strips 27a, 27b of a material with a low adhesion coefficient are inserted between the collimator 23 and the strips 25a, 25b of an elastic material, and between various elements formed of different materials, eg, a plate. Allows translational movement caused by different expansions between 24 and housing 20.

【0026】

In the illustrated embodiment, by using several assemblies formed by the LED and the optical means, the several assemblies formed by the LED and the optical means need to have a uniform lumen output. It becomes. Differences in lumen output between individual assemblies will reduce the aesthetics and / or efficiency of overall performance. Fixing the optical means in an optimal position with respect to the emission characteristics of the LED is particularly important to ensure the uniformity of light output of the LED and each assembly formed by the optical means. By ensuring the optimal individual positioning of the optical means with respect to the emission characteristics of each LED, the present invention paves the way for uniform illumination configurations of various shapes based on the emission of multiple LEDs. ..

【0027】

In the illustrated embodiment, the collimator 23 has a rectangular wide front surface 28 that is larger than the actual output surface of the light beam. This wide front surface 28 provides a support surface for two strips 25a, 25b of elastic material, which strips 25a, 25b are placed on the edge 28a, 28b of the front surface 28 so as not to reduce the luminous flux lumen. To do.

【0028】

The collimator is not rotationally symmetric because the front surface 28 is rectangular. It is desirable for aesthetic reasons to prevent rotation around an axis orthogonal to the plane defined by the front surface 28. This rotation is even unpleasant if the optical means are not rotationally symmetric for the purpose of generating an output beam that is also not rotationally symmetric. This rotation affects the photometric characteristics of the luminaire. This rotation is restricted by the shoulders 29a, 29b provided on the housing 20. In the embodiment shown in FIG. 2, however, it exists between the collimator 23 and the shoulders 29a, 29b in the housing 20 formed by extruding aluminum in view of the industrial treatment method used in housing manufacturing. Play is difficult to control. Therefore, this rotation is only roughly restricted.

【0029】

FIG. 3 shows a part of an improved embodiment of the luminaire of FIG. 2, and components similar to the embodiment of FIG. 2 will be described with the same reference numerals. This improved embodiment is identical in that it limits the range of rotational motion of the collimator 23 around an axis orthogonal to the plane defined by the front surface 28 of the collimator 23. A rigid piece 30 is inserted between the sequential front 28s of the collimator 23 for the purpose of this rotation limitation. The rigid portion piece 30 has dimensions calculated so as to create a clearance between the rigid portion piece 30 and the collimator 23. The presence of this rigid piece makes it possible to limit the degree of rotation of the collimator 23 without actually finishing the assembly of the collimator 23 into a rigid body, keeping the collimator 23 individually independent. It is possible to prevent stress from being applied to the LED22. In this embodiment, the optimum shape of these rigid pieces 30 is a parallelogram that fills the empty space between the two front 28s of the two collimators 23, but this shape is absolute. Many changes can be made to fit the shape arrangement of the luminaire and / or the optical means, not the one. These rigid portion pieces 30 can be used in combination with the present invention or independently of the present invention.

【0030】

Two protrusions 31a, 31b are provided on each rigid piece 30, and these protrusions 31a, 31b are used for the elastic material strips 25a, 25b shown in FIG. 2 and for the polyethylene strips 26a, 26b. Used as an abutting part for. According to these convex portions, it is possible to prevent these strips from covering the portion where the light beam of the front surface 28 of the collimator 23 is emitted to the outside. As another embodiment, these protrusions 31a and 31b can be provided on the front surface 28 of the collimator 23.

【0031】

FIG. 4 shows another embodiment of the rigid portion piece 30. These rigid piece pieces 30, which have a parallelogram shape and are inserted between the front surfaces 28 of the individual collimators 23, are grouped into, for example, two sets to form a single play adjustment piece 33. At the time of this grouping, the two parallelogram-shaped rigid portion pieces 30 are integrally connected by the connecting element 32. The play adjusting piece 33 can be formed, for example, by molding / casting any kind of rigid material. Molding and casting are particularly preferred because it is easy to form the convex portion 31.

【0032】

The special shape of the play adjusting piece 33 in this embodiment allows for limiting the movement of the rigid pieces 30 between the collimators 23 seen in the case of the individual rigid pieces 30.

[Simple explanation of drawings]

[Figure 1]

It is a vertical sectional view of the Example of the luminaire according to this invention.

[Figure 2]

It is an exploded perspective view of the luminaire of another Example of this invention.

[Fig. 3]

It is a perspective view seen from above of the luminaire as yet another embodiment which improved the luminaire of FIG.

[Fig. 4]

FIG. 3 is a perspective view of a piece for adjusting mechanical play used in a special embodiment of the type shown in FIGS. 2 and 3.

[Explanation of symbols]

1 housing 2 light emitting diode, i.e. LED 3 Support 4 Collimator 5 symmetrical sides 6 Front 7 bottom 8 cavities 9 dome 10 plates 11 Elastic material 12 Double-sided adhesive tape 13 Fine strips with low adhesive coefficient 14 Corrugated surface 20 housing 21 Support 22 LED 23 Collimator 24 plates 25 Strips of elastic material 26 Double-sided adhesive tape 27 Fine strips of material with low adhesion coefficient 28 Front 29 shoulders 30 Rigid part piece 31 Convex part 32 Connecting element 33 Play adjustment piece