Patent Document

BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to an electrical household appliance, in particular a refrigerator and/or freezer, having an appliance body with a body interior and a shelf, made of a light-permeable material and inserted into the body interior, for storing refrigerated and/or frozen goods. 
         [0003]    2. Description of the Prior Art 
         [0004]    In refrigerators and/or freezers for household use, there is generally a need for ensuring at least partial illumination of the interior in the opened state of the appliance in order to provide the user with better visibility of the objects inside. To achieve such illumination, there is the option of irradiating a light-permeable shelf with light from a narrow side of the shelf, the light coupled into the shelf being scattered at scattering points within the shelf, thus illuminating the shelf. Another option is to irradiate light from a light source directly into the interior of the appliance body, for example toward the top side of a shelf on which objects to be kept cold are situated. 
         [0005]    With regard to the prior art concerning interior illumination for a refrigerator and/or freezer, reference is made to US 2014/0376213 A1 by way of example. 
       SUMMARY OF THE INVENTION 
       [0006]    It is an object of the present invention to provide an approach having a simple design which allows a shelf in a refrigerator and/or freezer as well as a surrounding area in the interior of the appliance to be illuminated. 
         [0007]    To achieve this object, for an electrical household appliance of the type described at the outset, the invention additionally provides an illumination device having at least one light source, and one light-directing structure which couples one portion of the light generated by the light source into the shelf at its narrow side, and directs another portion of the light generated by the light source into the body interior. Exemplary embodiments of the invention are set forth in the subclaims. 
         [0008]    In the approach according to the invention, it is not necessary to use different light sources on the one hand for coupling light into a shelf at its narrow side, and on the other hand for irradiating light directly into the body interior. Instead, the light provided by a light source is split, one portion of this light being coupled into the shelf at its narrow side by the light-directing structure, and another portion being directed into the body interior by the light-directing structure. 
         [0009]    In one embodiment, it is provided that the other portion of the light generated by the light source, i.e., the portion that is not coupled into the shelf, is directed by the light-directing structure into the body interior in the direction beneath the shelf. Objects stored inside the electrical household appliance beneath the shelf may thus be well illuminated. 
         [0010]    In one embodiment, it is provided that the electrical household appliance has an appliance door mounted on the appliance body, through which the body interior is accessible to the user. The light-directing structure is situated adjacent to a front narrow side of the shelf facing the appliance door, and couples the one portion of the light generated by the light source into this front narrow side of the shelf. A cover part for covering the front narrow side of the shelf may be provided, at least a portion of the light-directing structure resting between the front narrow side of the shelf and the cover part. By use of such a cover part, the light-directing structure may be protected from damage due to impacts when objects are placed on the shelf or removed from it. Due to the coupling of a portion of the light into the shelf, it is possible to illuminate structures introduced within the shelf itself, such as logos or other design details. In addition, good illumination of the objects stored on the shelf may be achieved by light-scattering structures within the shelf. 
         [0011]    With regard to the design of the light-directing structure, it may be formed by a hollow profile member having at least one light source accommodated in the cavity thereof. For illuminating a large area of the body interior and the shelf, it may be advantageous to insert a support strip (for example, in the form of an elongated circuit board) into the hollow profile member, a plurality of light sources being mounted in succession on the support strip, in the longitudinal direction thereof. 
         [0012]    In one embodiment, the light-directing structure is formed by a light-directing wall made of a light-permeable material, the light-directing wall having a first wall section, situated in front of the narrow side of the shelf, and a second wall section which adjoins the first wall section, with the light source resting behind the light-directing wall, viewed from the shelf. The second wall section is situated in such a way that it preferably protrudes downwardly in the vertical direction relative to the shelf. The light source, viewed in a section perpendicular to the longitudinal extension of the shelf narrow side, may be offset downwardly relative to the center of the thickness of the shelf. The light source may even protrude downwardly, at least partially, relative to the shelf, and, for example, may be situated partially within the area of the thickness of the shelf and may partially protrude downwardly relative to the shelf. By selecting the position of the light source in relation to the shelf, the ratio of the portion of the light that is coupled into the shelf to the portion of the light that is directed into the body interior may be appropriately set. 
         [0013]    According to one possible embodiment, the first wall section, viewed in the section perpendicular to the longitudinal extension of the shelf narrow side, may have a nose on its side facing away from the narrow side of the shelf, which protrudes away from the shelf narrow side. Light from the light source enters the nose at its bottom side; the bridge of the nose causes a reflection, preferably a total reflection, of light from the light source in the direction toward the shelf narrow side. The first wall section may have a planar wall outer surface on its side facing the shelf narrow side. The second wall section, viewed in a section perpendicular to the longitudinal extension of the shelf narrow side, may extend with an arch-like curvature, whereby it curves away from the shelf with increasing distance from same. The second wall section may have essentially the same wall thickness throughout. 
         [0014]    According to one embodiment, the light source may be a light-emitting diode, preferably a light-emitting diode having a beam angle range of not less than 60 degrees or 90 degrees or 120 degrees in a plane perpendicular to the longitudinal extension of the shelf narrow side. 
         [0015]    Within the scope of one embodiment of the invention, it is possible that, of the radiant power emitted by the light source, a larger portion is directed by the light-directing structure into the body interior, and a smaller portion is coupled into the shelf narrow side. 
         [0016]    The invention is explained in greater detail below with reference to the appended drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective front view of a refrigerator with the door open, according to one exemplary embodiment 
           [0018]      FIG. 2  is a sectional view of components of an illumination device of the refrigerator in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Reference is first made to  FIG. 1 . The appliance illustrated therein is denoted overall by reference numeral  10 . The appliance is a refrigerator having a cabinet construction, which is used for keeping foods cold, and if needed may additionally have a freezer compartment which is situated either within the cooling chamber of the refrigerator  10  and closable with respect to the cooling chamber by a door, or, as in the case of top freezer or bottom freezer refrigerators, is situated above or below the cooling chamber. The refrigerator  10  has a cabinet body  12  with a base wall  14 , a top wall  16 , a rear wall  18 , and two side walls  20 . The cabinet body  12  forms an access opening  22  which is bordered by the base wall  14 , the top wall  16 , and the two side walls  20 , and which is closable by a cabinet door  24  which is hinged so that is pivotable about a vertical pivot axis, and through which an interior  26  of the refrigerator  10  is accessible to the user. 
         [0020]    The interior  26  of the refrigerator  10  may be equipped with a wide variety of built-in parts which are suitable for the storage and placement of foods. At least one of these built-in parts is a plate-shaped shelf  28  made of a light-permeable material (for example, glass or plastic), with a lighting strip  30  situated on its front narrow side, i.e., facing the user, which extends essentially over the entire width of the shelf  28  (i.e., from one of the side walls  20  to the opposite side wall  20 ). The lighting strip  30  has an illumination function for the shelf and also for the area of the interior  26  situated beneath the shelf  28 . For this purpose, the lighting strip  30  contains a plurality of light sources, situated in succession in the strip longitudinal direction (corresponding to a direction from one of the side walls  20  to the opposite side wall  20 ), a portion of whose light is coupled into the front narrow side of the shelf  28  and another portion of which is directed past the shelf  28  and into the area of the interior  26  situated beneath the shelf  28 . Particulars concerning the design of the lighting strip  30  are explained in greater detail below in conjunction with  FIG. 2 . 
         [0021]    The lighting strip  30  may be fastened to the shelf  28 . Alternatively, it may be mounted on the side walls  20  or on retaining elements (not illustrated in greater detail) which are fastened to the side walls  20 . Besides its illumination function, the lighting strip  30  provides for edge protection of the shelf  28  by covering the front narrow side of the shelf  28  and thus protecting if from mechanical damage. 
         [0022]    In the example shown, the refrigerator  10  contains an additional shelf  32 , which like the shelf  28  is used for placing foods on it. Although this is not illustrated in  FIG. 1 , the shelf  32  may also be equipped with a further lighting strip  30 . Regardless of whether the shelf  32  is equipped with its own lighting strip  30 , it is preferably likewise (the same as the shelf  28 ) made of a light-permeable, i.e., transparent or translucent, material. 
         [0023]    Reference is now also made to  FIG. 2  for explaining the design particulars of the lighting strip  30 . In this figure the lighting strip  30  is shown in a sectional illustration; a corresponding section plane is depicted in dashed lines and denoted by reference character E in  FIG. 1 . The lighting strip  30 , which forms an illumination device within the meaning of the invention, has a cover part  34  made of a light-impermeable material (plastic or metal, for example) which has an essentially constant cross section over the entire length of the lighting strip  30  and which forms a receptacle for a lighting unit  36 . The lighting unit  36  may be preassembled as a unit and inserted into the receptacle formed by the cover part  34 . The cover part  34 , viewed in the sectional illustration according to  FIG. 2 , as a rough approximation is designed as an angled strip having a horizontal upper strip leg  38  and a vertical strip leg  40  adjoining at essentially right angles to the strip leg  38 , and situated in front of the shelf  28  as viewed by the user of the refrigerator  10 . At a distance from the upper horizontal leg  38 , a further horizontal leg  42  which is shorter than the upper horizontal leg  38  and situated at a distance beneath the shelf  28 , viewed in the vertical direction, extends from the vertical leg  40 . The lighting unit  36  is inserted into the space between the upper horizontal leg  38  and the lower horizontal leg  42  of the cover part  34 . A secure connection between the lighting unit  36  and the cover part  34  may be established, for example, by a snap connection or an adhesive bond between the two components. 
         [0024]    The lighting unit  36  has a hollow profile member  44  manufactured from a light-permeable plastic by extrusion, for example, with a profile cavity  46  that is closed all around. An elongated circuit board  48  which is used as a support strip is inserted into the profile cavity  46 , and a plurality of light-emitting diodes  50  are mounted in succession on the circuit board in the strip longitudinal direction (corresponding to a direction perpendicular to the plane of the drawing in  FIG. 2 ). Only one of these light-emitting diodes  50  is discernible in  FIG. 2 . The following explanations for directing the light generated by the one light-emitting diode  50  in  FIG. 2  similarly apply for the remaining light-emitting diodes of the lighting unit  36 . The board plane of the circuit board  48  is vertically oriented, so that a center axis of the main beam lobe of each of the light-emitting diodes  50  is oriented essentially horizontally for a customary installation of the light-emitting diodes  50  on the circuit board  48 . 
         [0025]    A portion of the profile wall of the hollow profile member  44  forms a light-directing wall  52 , through which the light generated by the light-emitting diode  50  is directed into the shelf  28  and into the interior  26  of the refrigerator  10 . The light-directing wall  50  [sic;  52 ] is made up of a first wall section  54  and a second wall section  56 . The first wall section  54  is situated directly in front of the front narrow side of the shelf  28  denoted by reference numeral  58 , and in the example shown is in contact with this narrow side  58 . In other embodiments, an intermediate space may be present between the first wall section  54  and the narrow side  58  of the shelf  28 . Light which exits from the first wall section  54  is coupled into the shelf  28  via the narrow side  58 , as indicated by dashed-line arrows in  FIG. 2 . In contrast, light which exits through the second wall section  56  passes directly into the interior  26  of the refrigerator  10 , as indicated by a solid-line arrow in  FIG. 2 . The second wall section  56  bridges the vertical intermediate space between the lower horizontal leg  42  of the cover part  34  and the bottom side of the shelf  28 , and in this area extends at an angle with respect to the vertical direction. In the example case shown, the second wall section  56  is slightly curved, and has an essentially constant wall thickness in the area in which it is penetrated by light from the light-emitting diode  50 . 
         [0026]    The first wall section  54  has a planar design on its outer side facing the narrow side  58  of the shelf  28 , and on its inner side facing the profile cavity  46  has a nose-like projection  60 , at the bottom side of which (oriented vertically downwardly) light enters from the light-emitting diode  50  into the projection  60 , and whose nose bridge forms an optical interface with the air present in the profile cavity  46 , so that the light which has passed into the projection  60  may be totally reflected there via the nose underside. As an alternative to a totally reflective interface, it is conceivable to mirror coat the nose bridge with a reflective metal layer. 
         [0027]    It is apparent in  FIG. 2  that the light-emitting diode  50 , viewed in the vertical direction, protrudes partially downwardly over the bottom side of the shelf  28 . This is equivalent to a portion of the light-emitting diode  50  overlapping vertically with the shelf  58 . By a suitable selection of the vertical position of the light-emitting diode  50  relative to the shelf  28 , the ratio of the radiant power that is emitted by the light-emitting diode  50  through the second wall section  56  into the interior  26  of the refrigerator  10  to the radiant power that is coupled into the shelf  28  by the light-emitting diode  50  through the first wall section  54  via the shelf narrow side  58  may be set as desired. For example, of the radiant power that is emitted overall by the light-emitting diode  50 , a larger portion is emitted into the interior  26  through the second wall section  56 , and a smaller portion is coupled into the shelf  28  through the first wall section  54 . 
         [0028]    At its top side and/or at its bottom side and/or in its interior, the shelf  28  may be designed with one or more light-scattering structures which may be created, for example, by printing, sandblasting, engraving (by means of a laser, for example), or some other suitable method. These types of light-scattering structures may ensure good illumination of objects that are placed on the shelf  28 . 
         [0029]    The light-directing wall  52  together with the two wall sections  54 ,  56  forms a light-directing structure within the meaning of the invention. 
         [0030]    Although the preferred embodiments of the present invention have been described herein, the above description is merely illustrative. Further modification of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention as defined by the appended claims.

Technology Category: 2