Abstract:
The invention relates to an elongate light fixture having a substantially triangular cross-section. The light fixture is screwed to a supply duct with the rear wall thereof. A front rail runs parallel to the rear wall. Transparent panels and are inserted detachably between the rear wall and rail. In the interior of the light fixture, a fluorescent lamp is provided as the luminous element. The light emitted by said fluorescent lamp is reflected upward by way of reflector surfaces that open in the shape of a funnel and is scattered diffusely in the direction A by means of the frosted panel. The panel surfaces, which likewise open in the shape of a funnel, reflect the light exiting downward from the lamp in the direction toward the panel, the grooved structure of which ensures that the light is deflected substantially in the direction B, while the portion of the side light exiting in the direction C is reduced. With this reflector and panel configuration, firstly good illumination of the space and secondly specific and glare-free workplace lighting is made possible.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority from PCT Patent Application Ser. No. PCT/EP2009/007770, filed Oct. 29, 2009, the entire contents of which is herein incorporated fully by reference, which in turn claims priority form German Patent Application Serial No. 10 2009 007 308.6 filed Aug. 3, 2009. 
     
    
     FIGURE FOR PUBLICATION 
       [0002]    
       FIG. 2 
     
       BACKGROUND OF THE INVENTION 
       [0003]    1. Field of the Invention 
         [0004]    The present invention relates to a surface-mounted or wall-mounted luminaire with improved reflection. More particularly, the present invention relates to an elongate light fixture having a substantially triangular cross-section with a particular construction substantially enhancing direct and reflected light and which is operably useful in installation. 
         [0005]    2. Description of the Related Art 
         [0006]    The related art involves surface-mounted luminaries substantially composed of an elongated housing having an approximately triangular cross-section, the back wall of the housing being fastened to the media distributor. Inside the housing, a fluorescent lamp is disposed, the light of which is emitted directly to the workplace or indirectly in the direction of the room ceiling by way of reflectors that extend parallel to the lamp and screens disposed at an angle relative to each other. 
         [0007]    A surface-mounted luminaire for media supply is known from DE 20 2007 004 239 U1, which is incorporated by reference. Based upon this reference it is difficult to achieve an optimal workplace and space illumination while also being both easy to install and highly service-friendly. 
         [0008]    To solve the lighting problem, the surface-mounted luminaire provided is suitable for attachment to both the aforementioned media distributor or to a vertical wall. 
         [0009]    Accordingly, there is a need for an improved device enabling surface-mounting or wall-mounting luminaires, especially that is both easy to install and highly service-friendly. 
       ASPECTS AND SUMMARY OF THE INVENTION 
       [0010]    The proposed invention provides an elongate light fixture having a substantially triangular cross-section. The light fixture is screwed to a supply duct with the rear wall thereof A front rail runs parallel to the rear wall. Transparent panels and are inserted detachably between the rear wall and rail. In the interior of the light fixture, a fluorescent lamp is provided as the luminous element. The light emitted by said fluorescent lamp is reflected upward by way of reflector surfaces that open in the shape of a funnel and is scattered diffusely in the direction A by means of the frosted panel. The panel surfaces, which likewise open in the shape of a funnel, reflect the light exiting downward from the lamp in the direction toward the panel, the grooved structure of which ensures that the light is deflected substantially in the direction B, while the portion of the side light exiting in the direction C is reduced. With this reflector and panel configuration, firstly good illumination of the space and secondly specific and glare-free workplace lighting is made possible. 
         [0011]    An aspect of the present invention is to provide a luminaire that significantly improves the quality of the directly and indirectly emitted light. This is achieved, for one, by a particular reflector geometry, which ensures the emission of extremely homogeneous light both upward and downward relative to a fixed position, and secondly by the configuration of the screens which cover the luminaire toward the top and the bottom and by which the light is scattered diffusely upward and the light is oriented downward such that the portion of horizontally exiting light is as low as possible. 
         [0012]    It is another aspect of the proposed invention that reflector configurations are provided which both favor the light direction described and are economical to produce and install. 
         [0013]    It is also an aspect of the proposed invention that the screens used for light direction are removably insertedable. 
         [0014]    It is another aspect of the proposed invention that the resultant unit is easy production and improves the service friendliness, while offering safe handling for installers. 
         [0015]    It is another aspect of the proposed invention that at least one screen, located at the top, can be pivoted away for service purposes and that optionally a bottom screen can be securely fastened. 
         [0016]    It is another aspect of the proposed invention that solutions are proposed for fastening the lateral parts to the luminaire housing and for fastening the luminaire to a supply duct or a wall. 
         [0017]    Another aspect of the present invention provides a luminaire that is configured so that a plurality of luminaires of this type can be disposed in series next to one another, as is desirable for the aforementioned media distributor. 
         [0018]    Another aspect of the present invention provides a luminaire element that is not only easy to orient in series, but also is easy to install and remove. 
         [0019]    The above, and other aspects, features and advantages of the present invention will become apparent from the following description read in conduction with the accompanying drawings, in which like reference numerals designate the same elements. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a perspective illustration of a luminaire according to the invention, in which the top screen is open. 
           [0021]      FIG. 2  is a cross-section of the luminaire installed on a supply duct, having a schematically indicated beam path. 
           [0022]      FIG. 3  is a perspective and enlarged illustration of one of the two lateral parts of the luminaire shown in  FIG. 1 . 
           [0023]      FIG. 3A  is an enlarged detail III of the lateral part shown in  FIG. 3 . 
           [0024]      FIG. 4  is a cross-section of the luminaire according to  FIG. 1  close to the lateral part  10  with closed screens. 
           [0025]      FIG. 4A  is a cross-section according to  FIG. 4  with partially open screens. 
           [0026]      FIG. 5  is a cross-section of the luminaire screwed onto a supply duct. 
           [0027]      FIG. 5A  is an enlarged perspective detailed illustration of a keyhole-shaped opening provided in the rear wall, comprising a threaded pin used for fastening and a nut. 
           [0028]      FIG. 6  is a perspective partial views of two luminaire elements having top screens that are folded open, the elements being disposed in series and connected to one another, 
           [0029]      FIG. 6A  is a perspective larger illustration of a locking pin used to mechanically connect the luminaire elements. 
           [0030]      FIG. 7  is a cross-section of the luminaire according to  FIG. 4  with the top screen being entirely folded open. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    Reference will now be made in detail to several embodiments of the invention that are illustrated in the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms, such as top, bottom, up, down, over, above, and below may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope of the invention in any manner. The words “connect,” “couple,” and similar terms with their inflectional morphemes do not necessarily denote direct and immediate connections, but also include connections through mediate elements or devices. 
         [0032]    The luminaire housing is substantially composed of a rear wall  30 , to which lateral parts  10  and  20  are screwed perpendicularly by countersunk head screws  16 , the lateral parts being connected to one another at the front by means of a profiled rail  40 . This rail is also connected to the lateral parts  10  and  20  by means of countersunk head screws  16 . 
         [0033]    As is apparent in particular from  FIG. 3A , the countersunk holes  11  for receiving the countersunk head screws  16  are provided with lobular recesses  12 , which remove the paint adhering to the countersunk head screw when the same is screwed in and thereby ensure good electrical connection between the lateral parts  10 , the countersunk head screws  16  and the rear wall  30  connected thereto or the front profiled rail  40 . 
         [0034]    Inside the housing, a fluorescent lamp  2  is provided as the luminous element  2 , which is inserted in bases  3  attached to the lateral parts  10  and  20 . 
         [0035]    Reflectors are disposed between the rear wall  30  and fluorescent lamp  2 , with the drawing showing the reflector surfaces  61   a  and  62   c.    
         [0036]    The luminaire is covered toward the top and the bottom by transparent screens, of which only the upwardly folded-open screen  50  is shown in  FIG. 1 . 
         [0037]    For the electrical connection of the luminaire, connecting cables  91  are provided inside the luminaire housing between the rear wall  30  and the reflector  61   a,  wherein the plugs  92  and sockets  93  located at the ends of the cables are shown, which can be guided through feedthrough openings  18  or  18 ′ provided in the lateral walls  10  or  20 . Moreover, locking pins  15  and detent openings  17  associated with one another are provided in the lateral parts  10  and  20  and are used to orient and lock the luminaire elements disposed in series, as will be explained in more detail hereinafter. 
         [0038]    Keyhole-shaped openings  31  are provided in series next to one another for fastening the luminaire  1  to a rear wall, which is not shown in  FIG. 1 . 
         [0039]    The most important measures for the configuration of the luminaire according to the invention relate to the light distribution and light direction, the latter being illustrated by the cross-section according to  FIG. 2 , which schematically indicates the light beams generated by the lamp  2  for generating the indirect light A, for generating the direct light B and the lateral light C. 
         [0040]    The light direction symbolized here is made possible by the special configuration of the rear reflector comprising the reflector surfaces  61   a  and  61   b  and the front reflector comprising the reflector surfaces  62   a,    62   b  and the screens  50  and  70 . 
         [0041]    The reflector surfaces  61   a  and  62   a  delimit a bottom chamber  63  opening downward in a funnel shape, and the reflector surfaces  61   b,    62   b,  and  62   c  delimit a top chamber  64  opening upward in a funnel shape. 
         [0042]    The bottom chamber  63  is covered by a bottom screen  70  having a flute-shaped structure. The reflector surfaces  61   a  and  62   a,  together with the fluted bottom screen  70 , cause the light generated by the lamp  2  for illuminating the workplace to be deflected notably perpendicularly downward in the direction B, while laterally emitted light in direction C is substantially suppressed, which results in extraordinarily good freedom of glare. 
         [0043]    The top chamber  64  is covered by a frosted screen  50 . The light emitted upward by the lamp  20  is reflected by means of the reflector surfaces  61   b,    62   b  and  62   c  and diffusely scattered more strongly by means of the frosted screen  50  than by the bottom screen  70 , whereby indirect light that is emitted in direction A and reflected by the room ceiling is generated. 
         [0044]    For design reasons, the reflector surfaces  61   a  and  61   b  and the reflector surfaces  62   a,    62   b  and  62   c  are integrally produced, respectively. 
         [0045]    The design measures also proposed by the invention and described in more detail based on the remaining figures are no less important for production, installation and maintenance. 
         [0046]    The configurations and arrangements of the top screen  50  and bottom screen  70  are important for installation and maintenance; they are disposed between the rear wall  30  and the forward rail  40 , which are advantageously produced as extruded sections. 
         [0047]    With a lip  51   a  which is located at the rear edge  51  and bent downwardly, the top screen  50  is pivotably suspended in a flute  35  provided at the upper edge of the rear wall. The top screen  50  can thus be pivoted away toward the top, as is shown in  FIG. 4   a . A front lip  51   b,  which likewise runs at the rear edge of the top screen  50  parallel to the lip  51   a  and is seated against the front wall part  35   a  of the rear wall  30  that delimits the flute  35 , prevents the top screen  50  from being detached when it is folded up. Given this special shape, the top screen  50  can also be easily installed and removed without tools. 
         [0048]    The rear wall  30  advantageously transitions upward into an extension  35   c  forming a stop for the screen  50 , the operating principle of the extension being apparent in particular from  FIG. 7 . 
         [0049]    This configuration makes it possible for the screen  50  to be locked in the folded-up state, so that the service technician has both hands free when replacing the lamp, performing the repair work or cleaning. 
         [0050]    At the front end, the closed top screen  50  engages with a groove  42  of the profiled rail  40  via a downwardly directed, elastically spring-loaded lip  52  for locking purposes. The top screen  50  and the profiled rail  40  are dimensioned such that, when the screen  50  is closed, the surface thereof is flush with the surface of the rail  40 , so that only a narrow gap is formed between the mutually adjoining edges of the screen  50  and rail  40 . This substantially prevents accidental opening of the screen, because a tool, for example a screwdriver to be introduced in the gap, is required for opening. 
         [0051]    For service purposes, for example to replace a lamp  2 , it suffices to open the top screen  50 , and the bottom screen  70  can remain fixedly installed. However, so as to enable economical production, the rear wall  30 , rail  40  and the lateral parts  10  and  20  are configured so that easy installation and removal are possible. The screen  70 , for example, comprises edges  71  that are tapered on both sides relative to the screen thickness, which are removably inserted on one side in a groove  32  of the profiled rear wall  30  and on the other side in a groove  41  of the profiled rail  40 . The distance between the mutually facing edges  32   a  of the rear wall  30 , and  41   a  of the rail  40 , is smaller than the width of the inserted screen  70 , while the distance of the bases  41   b  of the groove  41 , and  32   b  of the groove  32 , is larger than the width of the bottom screen  70 , whereby easy insertion and retention of the screen  70  are assured. So as to fix the screen  70  in the position thereof, a fixing pin  13  engages in the intermediate space between the groove base  32   b  and the edge  71  of the screen  70 , the pin being provided on the lateral part  10 , as is shown in particular in  FIG. 3 . The edges  71  and  72  of the bottom screen  70  and the screen are dimensioned such that a smooth transition is obtained when the screen  70  is inserted. 
         [0052]    In particular when using the luminaire as a luminaire element in a lighting strip, the easy and flush installation thereof is required. For this purpose, a series of keyhole-shaped openings  31  are provided in the rear wall  30  of the luminaire  1 , which have already been mentioned in connection with  FIG. 1 . 
         [0053]    The special configuration of the openings is shown in the perspective illustration according to  FIG. 5A . During installation, the luminaire  1  is placed on threaded pins  81  located on the supply duct  80 , which penetrate the keyhole-shaped openings  31 . The nuts, preferably self-locking nuts  33  with serrated bearing surfaces, screwed onto the threaded pins  81  must be tightened to fix the luminaire  1 . The elongated hole  31  a provided on the opening  31  makes it possible to orient the luminaire  1  vertically. 
         [0054]    To further fix the position of and mount the luminaire, an upwardly bent lug  82  which engages in a receiving flute  36  of the rear wall  30  is provided at the lower end of the supply duct  80 . This ensures secure fastening of the luminaire. As soon as the luminaire  1  is suspended on the threaded pins  81  and the self-locking nuts  33  with serrated bearing surfaces are screwed on, the luminaire is fixed in place. The lug  82  prevents the luminaire from being pushed upward. Even if the self-locking nut  33  with serrated bearing surfaces is not tightened, secure fastening is assured. 
         [0055]    When the luminaire elements  1 ,  1 ′ are used in a strip lighting fixture, as is shown in  FIG. 6 , it is important that they are oriented such that they are aligned with one another. 
         [0056]    So as to ensure or facilitate this, a spring-loaded locking pin  15 ′ is provided in each lateral wall  10 ′, the pin engaging in a detent opening  17  associated therewith, which is apparent, for example, from  FIGS. 1 and 3 . During removal, this locking pin  15 ′ must be loosened. 
         [0057]    To remove a luminaire element  1  or  1 ′ from the lighting strip, not only the fastening and locking elements  81  and  15  must be loosened, but the electrical connections of the cables  91 ,  91 ′ must also be disconnected. For this reason, the cables  91 ,  91 ′ are equipped at the mutually associated ends with plugs  92 ′ or sockets  93 , which can easily be connected to one another and disconnected from one another. 
         [0058]    The spaces between the rear walls  30 ,  30 ′ and the reflector surfaces  61   a  and  61   a′  are dimensioned such that, after the connecting cables  91  and  91 ′ are disconnected, they can be stored together with the sockets  93  and plugs  91 ′ without difficulty behind the reflectors  61   a  and  61   a′.    
         [0059]    In the claims, means or step-plus-function clauses are intended to cover the structures described or suggested herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, for example, although a nail, a screw, and a bolt may not be structural equivalents in that a nail relies on friction between a wooden part and a cylindrical surface, a screw&#39;s helical surface positively engages the wooden part, and a bolt&#39;s head and nut compress opposite sides of a wooden part, in the environment of fastening wooden parts, a nail, a screw, and a bolt may be readily understood by those skilled in the art as equivalent structures. 
         [0060]    Having described at least one of the preferred embodiments of the present invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes, modifications, and adaptations may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.