Patent Publication Number: US-2022235942-A1

Title: Cooking device with holding plate for a cooking device light

Description:
RELATED APPLICATIONS 
     This application claims priority from and incorporates by reference German Patent Application DE 10 2021 101 699.1 filed on Jan. 26, 2021. 
     FIELD OF THE INVENTION 
     The invention relates to a cooking appliance including a cooking appliance light. 
     BACKGROUND OF THE INVENTION 
     Cooking devices are known in the art configured as ovens, steam cookers, microwave ovens or other devices for home use and commercial use. They are used for preparing foods and include a cooking cavity that is formed by a so-called muffle and its walls, thus the muffle walls or the cooking cavity walls. 
     In order to be able to watch and assess the cooking process, cooking devices include lighting as described e.g. in DE 50 2006 001 187 owned by applicant. Lights of this type are arranged in pass through openings of the cooking cavity wall that are introduced into the cooking cavity wall during fabrication of the muffle. 
     The muffle is typically made from plural metal components. Muffle elements are stamped from sheet metal. 
     Tools and equipment for fabricating muffle elements are quite expensive so that manufacturing of cooking devices strive to sufficiently load the tooling by using the same muffle in various types and models of appliances. 
     Recent developments in illumination technology have led to an increased use of cooking cavity lights that are based on LED modules that provide high energy saving potential and thus improve energy efficiency of cooking appliances. However specific requirements of LED lighting technology led to new cooking cavity lights that have different configurations, installation dimensions and arrangement requirements in the cooking appliance. In particular temperature sensitivity of the LED light source has the effect that the LED light source has to be arranged at a significantly larger distance from the cooking cavity and that the emitted light is typically conducted into the cooking cavity through a light conductor. This has the effect that oven muffles with accordingly configured wall openings are developed for using LED based cooking appliance lights for conducting the light into the cooking cavity and existing production tooling has to be adapted or replaced. This is detrimental from an economic and environmental point of view. 
     BRIEF SUMMARY OF THE INVENTION 
     Thus, it is an object of the invention to provide a microwave oven with an LED based cooking appliance light using an opening in the cooking cavity wall that is configured for conventional lights. 
     The object is achieved by A cooking appliance including a cooking cavity defined by a cooking cavity wall; a cut out provided in the cooking cavity wall; a cooking appliance light arranged in the cut out and configured to illuminate the cooking cavity; and a support plate including a receiving opening for the cooking appliance light, wherein the cooking appliance light is supported in the receiving opening, wherein the support plate fixes the cooking appliance light in the cut out, wherein the support plate including the cooking appliance light closes the cut out in the cooking cavity wall, wherein the cooking appliance light includes a LED illuminant and a light conductor rod, wherein the light conductor rod is supported in the cut out in the cooking cavity wall. 
     Thus, the cut out in the cooking cavity wall has a first opening dimension, the receiving opening of the mounting plate, however has a second opening dimension that is reduced relative to the first opening dimension. 
     The invention is characterized in particular by the mounting plate described supra which adapts the mounting contour and mounting position defined by the opening in the cooking cavity wall for using an LED illuminant. This way neither the cooking cavity wall which is part of the muffle has to be adapted to modern LED based cooking appliance lights nor efforts have to be made to redesign cooking appliance lights which have been developed to use advantageous LED technology so that the LED cooking appliance lights are adapted to existing cooking appliance walls that are still configured for conventional lights. 
     Thus, the mounting plate according to the invention facilitates a continued use of production tooling that is configured for producing components for conventional illumination until tooling has to be acquired e.g. due to wear which goes hand in hand with a change in tooling. Simultaneously illuminants adapted to new requirements can be used without redesign, thus the mounting plate facilitates a seamless and soft transition from conventional technology to new technology. 
     Typically the cut outs in the cooking cavity wall include grooves. With conventional illuminants the grooves typically secure the lamp socket against rotation in order to be able to rotate a glass cover relative to a socket housing and remove the glass cover for replacing the illuminant. The invention proposes to use this groove as a positioning groove in order to assure a defined orientation of the mounting plate. Thus, the mounting plate forms a positioning lug that engages the positioning groove. 
     In an advantageous embodiment the mounting plate, in particular the positioning lug of the mounting plate includes at least one interlocking lug that reaches behind the cooking cavity wall, in particular when the mounting plate includes at least one mounting base that reaches behind the cooking cavity wall. 
     This way it is assured that the mounting plate is easily insertable into an existing cutout in the cooking cavity wall and that the mounting plate is securely retained therein. 
     Advantageously the mounting plate includes an alignment contour for correctly positioning the cooking appliance light in the mounting plate. This assures that the LED based cooking appliance light is installed in the cooking cavity wall with a correct orientation through the cooperation of positioning groove and positioning lug. This is an essential prerequisite for light fed into the cooking cavity to be radiated in a defined manner e.g. by coating the light conductor. 
     From a fabrication point of view it is advantageous when the mounting plate is configured as a stamped component in which the mounting base and the positioning lug are bent from the material of the mounting plate. 
     The cooking appliance light advantageously includes a mounting socket that fixes the cooking appliance light in the mounting plate. 
     In order to prevent an exit of cooking gases through the cut out in the cooking cavity wall an elastic element is arranged between the mounting socket and the mounting plate wherein the elastic element has a sealing effect. 
     Alternatively, the mounting plate is provided with a seal element with a receiver for the light conductor rod of the cooking cavity light. The seal element prevents an exit of cooking gasses from the cooking cavity but also supports the cooking cavity light. 
     In particular the mounting plate is provided annular and includes two mounting bases and a positioning lug wherein the mounting bases and the positioning lug are respectively circumferentially offset by approximately 120 degrees. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is subsequently described in more detail based on two embodiments with reference to drawing figures, wherein: 
         FIG. 1  illustrates a first embodiment of the cooking appliance light in an exploded view; 
         FIG. 2  illustrates a top view of the cooking appliance light according to  FIG. 1 ; 
         FIG. 3  illustrates a sectional view according to sectional line in  FIG. 2 ; 
         FIG. 4  illustrates a mounting plate in a perspective view of a top side; 
         FIG. 5  illustrates the mounting plate according to  FIG. 4  in a perspective view of a bottom side; 
         FIG. 6  illustrates a second embodiment of the invention; 
         FIG. 7  illustrates a top view of the embodiment according to  FIG. 6 ; 
         FIG. 8  illustrates a sectional view according to the section line VIII-VIII in  FIG. 7 ; 
         FIG. 9  illustrates a mounting plate according to the second embodiment in a top view; 
         FIG. 10  illustrates the mounting plate according to  FIG. 9  in a bottom view; 
         FIG. 11  illustrates a perspective view of the mounting bracket shown in  FIG. 1 ; and 
         FIG. 12  illustrates a sectional view according to the section line XII-XII in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The drawing figures show an arrangement of a cooking appliance light in a cooking cavity wall section overall designated with the reference numeral  10  and shown in  FIGS. 1-5  in a first embodiment and in  FIGS. 6-10  in a second embodiment.  FIGS. 11-12  show additional components of the first or second embodiment of the invention. Only components essential for the particular embodiment are shown. 
       FIG. 1  illustrates the arrangement  10  with a section of a cooking cavity wall  11  of a cooking appliance. The cooking cavity wall  11  includes a cut out  12  that is substantially circular and that forms a positioning groove  13 . 
       FIG. 1  shows the light conductor rod  14  of the cooking appliance light  48 . A LED module  49  including support and cooling element that introduces light into the light conductor rod  14  is attached at the light conductor rod. 
     The mounting socket  15  includes a bore hole  16  that penetrates the mounting socket  15  and that is used for receiving the light conductor rod  14 . The mounting socket  15  supports a graphite ring  17  that seals relative to the light conductor rod  14  and which is supported at the mounting base  15  by a mounting bracket  18 . The mounting bracket  18  is fixed at the mounting socket  15  by retaining pins  19 . 
     A support plate  20  receives the mounting socket  15  with a sealing elastic element  21  arranged between the support plate and the mounting socket so that the mounting socket  15  is supported in the cut out  12  of the cooking cavity wall  11 . 
     The support plate  20  is shown in a perspective top view in  FIG. 4  and in a perspective bottom view in  FIG. 5 . The support plate  20  is annular. Its diameter is larger than the diameter of the cut out  12  of the cooking cavity wall  11  in order to be able to cover the cut out  12 . 
     The support plate  20  includes a receiving opening  47  and a positioning lug  22  and forms two retaining bases  23  that are bent out of the annular wall  24  of the support plate  20  in identical directions toward a bottom side of the support plate  20  in the embodiment according to  FIGS. 4 and 5 . 
     The positioning lug  22  is configured substantially V-shaped, wherein an originating arm  25  connected to the support plate  20  extends downward relative to the support plate  20  and transitions at its lowest point through a connection arc into a positioning arm  26 . The positioning arm  26  itself is oriented in a direction towards a top side of the support plate  20 , wherein a free end of the positioning arm  26  extends at least into a plane of the annular wall  24  of the support plate  20 , but the positioning arm  26  can also penetrate the annular wall  24  of the support plate  20  in upward direction. 
     Furthermore, the positioning arm  26  includes an interlocking lug  27  that is bent radially outward and that provides attachment by reaching behind the cooking cavity wall  11 . 
     The annular wall  24  of the support plate  20  forms an annular cavity  28  that receives the mounting socket  15 . Thus, the annular cavity  28  is the receiving opening of the support plate  20 . Additionally, the annular cavity  28  respectively transitions into an alignment contour  29  in the first embodiment at two diametrically apposed sections. The alignment contour  29  is formed congruent to alignment devices  30  of the mounting socket  15  described infra and thus facilitates defined positioning the mounting socket  15  in the support plate  20 . 
     An origin of the mounting bases  23  as well as the origin of the originating arm  25 , thus the respective root that ties the mounting bases  23  or the positioning lug  22  to the annular wall  24  of the support plate  20  are arranged on a common radius. This radius is slightly reduced relative to the radius of the cut out  12  of the cooking cavity wall  11  so that the root of the mounting bases  23  and the root of the originating arm  25  are arrangeable within the cut out  12 . The free ends of the mounting bases  23  are arranged on an accordingly larger radius so that they can reach behind or below the cooking cavity wall  11  on a side that is opposite to the support plate  20 . 
       FIG. 11  shows the attachment bracket  18  by itself. The attachment bracket  18  includes a base bar  31  that includes a central pass-through opening  32  for the light conductor rod  14  and a respective retaining pin opening  33  on a right side and a left side of the pass-through opening  32 . 
     The base bar  31  fixes the graphite ring  17  in a mounting bracket  43  of the mounting socket  15  as illustrated in  FIGS. 3 and 12 . The base bar respectively includes an interlocking arm  34 , wherein the interlocking arms  34  are bent funnel shaped from their root at the base bar  31 . Each interlocking arm  34  is bent at its free end against the deflection direction. These formed ends respectively form a centering and interlocking section  35 . Directly in front of a bending line that defines a transition into the centering and interlocking section  35 , a reset elastic fixing base  36  is bent outward from each interlocking arm  34 , wherein a free end of fixing base  36  is arranged approximately at a level of the bending line of the respective fixing base  36 . 
       FIGS. 3 and 12  show the arrangement  10  according to  FIG. 1  in a mounted condition according to the sectional lines or XII-XII in  FIG. 2 . Both figures initially show the bore hole  16  of the mounting socket  15  that receives the light conductor rod  14  and the support chamber  43  for the graphite ring  17  that is formed by the mounting socket  15 , wherein the graphite ring  17  seals the bore hole  16  relative to the light conductor rod  14  and thus prevents an exit of cooking vapors through the bore hole  16 . 
     The mounting socket  15  forms a sealing collar  44  that forms a sealing groove  45  that is open in a direction towards the support plate  20  wherein the sealing elastic element  21  is arranged in the open sealing groove  45  and prevents an exit of cooking vapors through the annular cavity  28  past the mounting socket  15 . 
       FIG. 3  shows how the support plate  20  is supported in the cut out  12 , wherein the positioning lug  22  is inserted into the positioning groove  13 . The free end of the positioning arm  26  is arranged in the plane of the cooking cavity wall  11 . The locking lug  27  reaches behind the cooking cavity wall  11  and thus secures the support plate  20  at the cooking cavity wall  11  together with the mounting bases. 
     A function of the mounting bracket  18  is now further described with reference to  FIG. 12 . The mounting bracket  18  is secured at the mounting socket  15  by the retaining pins  19  which penetrate the retaining pin openings  33  and engage dead holes  46  of the mounting socket  15  so that the attachment bracket  18  supports the graphite ring  17  in the retaining chamber  43 . 
     The interlocking arms  34  that are bent into a funnel shape and are oriented away from the bore hole  16  of the mounting socket  15 , engage the alignment contours  29  of the support plate  20 , wherein the support plate  20  is supported between the centering and interlocking section  35  of each interlocking arm  34  and the sealing collar  44  of the mounting socket  15 . Thus, the interlocking arms  34  function as alignment devices  30  for the mounting socket  15 . 
     A forming portion that is formed by the respective centering and interlocking section  35  of each interlocking arm  34  protrudes relative to an inner edge of the support plate  20  that forms the respective alignment contour  29  and thus functions as an interlocking protrusion that reaches behind the support plate  20 . Slanted surfaces of the centering and interlocking section  35  align the support plate  20  relative to the mounting socket  15  and compensate for fabrication tolerances. Each fixing base  36  provides a pull-out safety for the support plate  20  at the mounting socket  15  and can additionally reach behind the cooking cavity wall  11  with a corresponding deflection so that the mounting plate is supported at the cooking cavity wall  11  in addition to the mounting bases  23  and the interlocking lug  27  of the positioning arm  26 . 
       FIGS. 6-10  illustrate another embodiment of the invention. The exploded view according to claim  6  shows the arrangement  10  of the cooking cavity light represented by the light conductor rod  14  and a cut out portion of the cooking cavity wall  11  showing essential components. The cooking cavity wall  11  and the support plate  20  are essentially configured according to the first embodiment so that their descriptions provided supra also apply to the second embodiment. 
     In particular also the second embodiment includes a cut out  12  in the cooking cavity wall  11  wherein the cut out forms a positioning groove  13 . The support plate  20  illustrated in  FIGS. 9 and 10  in a perspective view from above or from below also includes a positioning lug  22  that is configured according to the first embodiment and support bases  23  that correspond to the first embodiment. Also, here the annular wall  24  forms an annular cavity  28 , however an alignment contour  29  is omitted. Another significant difference from the first embodiment is an annular collar  37  that is formed by the annular wall  24  and that protrudes from the bottom side of the support plate  20 . 
     The second embodiment of the invention according to  FIG. 6  additionally includes a seal element  38  with a central cut out  39  that functions as a receiver  40  for the light conductor rod  14 . 
       FIG. 8  illustrates a sectional view according to the section line VIII-VIII in  FIG. 7  and shows the arrangement of the second embodiment according to  FIG. 6  in assembled condition. The seal element  38  is arranged in the annular cavity  28  of the support plate  20 . A circumferential grove  41  formed on an outer circumference of the seal element  38  receives an edge of the annular wall  24  that defines the annular cavity  28  wherein the annular collar  37  is received in the annular groove  41 . 
     The mounting plate  20  that receives the seal element  38  is inserted into the cut out  12  of the cooking cavity wall  11  wherein the support bases  23  reach behind the cooking cavity wall  11  and thus receive the cooking cavity wall  11  between themselves and the annular wall  24  that sits on the cooking cavity wall  11 . The positioning lug  22  of the support plate  20  sits in the positioning groove  13  of the cut out  12  wherein the free end of the positioning arm  26  sits in the plane of the cooking cavity wall  11 , whereas the interlocking lug  27  reaches behind the cooking cavity wall  11  and thus anchors the support plate  20  in the cut out  12 . The light conductor rod  14  of the cooking appliance light sits in the receiver  40  of the seal element  38  and thus retains the cooking appliance light at the cooking cavity wall  11 , which does not preclude additional fasteners in particular in a light portion that is oriented away from the free end of the light conductor rod. 
     Both embodiments show how a cooking cavity wall  11  with a cut out  12  for anchoring conventional cooking cavity lights with halogen or incandescent bulbs can be provided with a modern LED technology cooking cavity light using an adapted support plate  20 . In particular a cooking appliance lights with a light conductor rod  14  only requires small cut outs  12  in the cooking cavity wall  11  in order to feed the light into the cooking cavity. The support plate  20  reduces the diameter of the cut out  12  to a size that is suitable for inserting a light conductor rod  14  possibly additionally using a mounting socket  15  or a seal element  38 . Furthermore, the support plate  20  can be used to fix the cooking appliance light in the cooking appliance, in particular when the support plate  20  receives a mounting socket  15 . Therefore, the support plate  20  is an adapter plate. The adapter plate facilitates using existing dies and tools and LED lights without having to adapt a configuration of the LED lights to instant installation conditions. 
     Thus, it is a key feature of the invention to provide a suitable feed for the light conductor rod  14  by reducing dimensions of an oversized cut out of the cooking cavity wall  11  by using the support plate  20  for passing the light conductor rod  14  through. 
     Though the preceding description shows circular cut outs  12  and a circular adaptor plate  20 , the key feature of the invention is also suitable for less common rectangular or otherwise shaped cut outs by adapting the shape of the support plate  20  and a shape of the seal element  38  or the mounting socket  15 . In addition to circular cylindrical light conductor rods, also rectangular or oval light conductor rods and light conductor rods with non-symmetrical cross sections are known. The teachings of the inventions can also be adapted to these light conductor rods. 
     REFERENCE NUMERALS AND DESIGNATIONS 
       10  arrangement with cooking appliance light 
       11  cooking cavity wall 
       12  cut out 
       13  positioning groove 
       14  light conductor rod, cooking appliance light 
       15  mounting socket 
       16  bore hole 
       17  graphite ring 
       18  mounting bracket 
       19  retaining pin 
       20  support plate 
       21  sealing elastic element 
       22  positioning lug 
       23  mounting base 
       24  annular wall 
       25  originating arm 
       26  positioning arm 
       27  interlocking lug 
       28  annular cavity 
       29  alignment contour 
       30  alignment device 
       31  base bar 
       32  pass-through opening 
       33  retaining pin opening 
       34  interlocking arm 
       35  centering and interlocking section 
       36  fixing base 
       37  annular collar 
       38  seal element 
       39  cut out 
       40  receiver 
       41  annular groove 
       42  undercut 
       43  mounting bracket 
       44  sealing collar 
       45  sealing groove 
       46  dead hole 
       47  receiving opening 
       48  cooking appliance light 
       49  LED illuminant