Patent Publication Number: US-9840862-B2

Title: Oven door opening magnetic hinge

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 14/294,183, filed on Jun. 3, 2014, entitled “OVEN DOOR OPENING MAGNETIC HINGE,” the disclosure of which is hereby incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     The present invention generally relates to an oven door hinge used to connect the oven door to the main oven unit, and more particularly to an oven door hinge that utilizes magnets to provide a closing force sufficient to keep the door closed against the oven opening. 
     BACKGROUND OF THE DISCLOSURE 
     Ovens and other appliances having doors that rotate to open by downward rotation, require hinges connecting the oven door to the main appliance unit that provide a closing force sufficient to keep the door closed against the weight of the door. Such closing force may prevent unintended opening and, in the case of an oven or the like, provide proper insulation. For such operation it is also generally desired for the hinges to also provide balancing force sufficient to maintain a partially open position of the door, as desired by the user. Generally, oven door hinges are configured such that the hinges apply the closing force when the door is at a position within a desired angle from the closed position and such that the balancing force is applied through the remainder of the range of motion provided by the hinge, up until the door is fully opened. 
     Oven door hinges have used various mechanisms including combinations of linkages, multiple springs, or cams to provide the desired combination of closing and balancing forces within the desired portions of oven door range of motion. Such mechanisms can be mechanically complex, resulting in high tooling and assembly costs and introducing multiple failure modes. Accordingly further advances for hinges used in ovens and other appliances are desired. 
     SUMMARY OF THE DISCLOSURE 
     According to one aspect of the present disclosure, a hinge for rotatably coupling an appliance door with an appliance body includes an input arm affixable with the body and a housing affixable within the door and coupled with the input arm so as to be rotatable through a range of motion between a closed position and an open position. The hinge further includes a spring engaged between the housing and the input arm and deformable to apply a balancing torque to the housing relative to the input arm and a first magnet coupled with one of the housing and the input arm and magnetically applying a closing torque between the housing relative and the input arm when the housing is within a predetermined range of the closed position. 
     According to another aspect of the present disclosure, an appliance includes a body defining an opening with a lower edge and a door positionable over the opening of the body. The appliance further includes a hinge having an input arm coupled to the body and a housing extending along a first axis within the door and rotatably coupled with the input arm such that the door is rotatable adjacent the lower edge of the opening and rotates away from the opening in a vertical direction between a closed position and an open position. The hinge further has a spring engaged between the housing and the input arm and deformable to apply a balancing torque to the input arm relative to the housing that substantially matches a weight torque of the door about the hinge and a first magnet coupled with one of the housing and the input arm and magnetically applying a closing torque between the housing relative and the input arm when the housing is within about 25 degrees from the closed position. 
     According to yet another aspect of the present disclosure, a hinge for rotatably coupling a door with a body includes a housing extending along a first axis and affixable within the door and an input arm coupled to the housing and rotatable through a range of motion between a closed position and an open position, the input arm being affixable with the appliance body. A spring is engaged between the housing and the input arm and is deformable to apply a balancing torque to the input arm relative to the housing during rotation of the input arm relative to the housing. A first magnet is coupled with one of the housing and the input arm and magnetically applies a closing torque between the housing relative and the input arm when the housing is within a predetermined range of the closed position. 
     These and other aspects, objects, and features of the present disclosure will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a hinge; 
         FIG. 2  is a perspective view of an oven with which one or more hinges according to  FIG. 1  can be used; 
         FIG. 3  is a cutaway view of a hinge showing various internal features thereof in a first position; 
         FIG. 4  is a further cutaway view of the hinge of  FIG. 3  in a second position; 
         FIG. 5  is a further cutaway view of the hinge of  FIG. 3  in a third position; 
         FIG. 6  is a graph showing the levels of various torques provided by the hinge throughout a range of motion thereof; 
         FIG. 7  is a cutaway view of an alternative hinge showing various internal features thereof in a first position; 
         FIG. 8  is a further cutaway view of the hinge of  FIG. 7  in a second position; and 
         FIG. 9  is a further cutaway view of the hinge of  FIG. 3  in a third position. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the disclosure as oriented in  FIG. 1 . However, it is to be understood that the disclosure may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     Referring to  FIGS. 1-9 , reference numeral  10  generally designates a hinge for rotatably coupling a door  12  of an appliance  14  with a body  16  thereof. Hinge  10  includes an input arm  20  affixable with the body  16  and a housing  18  affixable within the door  12  and coupled with the input arm so as to be rotatable through a range of motion  22  ( FIG. 6 ) between a first position (for example, housing  18   c  in  FIG. 3 ) and a second position (for example, housing  18   o  in  FIG. 5 ). A spring  24  is operably engaged between the housing  18  and the input arm  20  to apply a balancing torque to the housing  18  relative to the input arm  20 . A first magnet  26  is fixed relative to the housing  18 , and a second magnet  28  is movably received within the housing  18  and is operatively coupled with the input arm  20  so as to be positioned adjacent the first magnet  26  when the housing  18  is in the first position and moved away from the first magnet  26  by rotation of the housing  18  with respect to the input arm  20  from the first position toward the second position. A mutual attraction between the first and second magnets  26  and  28  applies a closing torque to the housing  18  relative to the input arm  20  when the housing  18  is within about 25 degrees from the first position. 
     As shown in  FIG. 2 , appliance  14  can be in the form of an oven or another similar appliance wherein a door  12  is mounted to the body  16  of the appliance to cover an opening  32  along a vertical face  34  of the appliance  14 , and more particularly, one in which one or more hinges  10  rotatably couple door  12  to the body  16  at a location adjacent a lower edge  36  of the opening  32 . In such an arrangement the hinges  10  provide for rotation of door  12  about a horizontal axis  38  such that the door  10  opens in a vertical direction, downward and away from the opening  32 . In an appliance  14  with a door  12  positioned for such downwardly rotating opening, it may be desired to provide a hinge  10  that is capable of balancing against the weight of a partially opened door through a range of possible positions of door  12  such that a user may open door  12  to a desired, partially-open position that the hinge  10  will maintain. 
     Further, additional functionality may be desired in which the hinge  10  can facilitate complete and secure closing of a door  12  over an opening  32  of an appliance  14 . This functionality can help to fully close door  12  when a user, for example, brings the door  12  to within a predetermined range proximate to the fully closed position (as indicated by door  12   c  in  FIG. 2 ). Further hinge  10  can be configured to provide an additional force to help maintain the door  12  in a fully closed position against body  16 . This force may supplement the force of the spring  24 , which may be low or zero in the instance of a fully closed door  12   c . Both the balancing force and the closing force may be referred to as a balancing torque and a closing torque, as the forces related thereto are applied about axis  38 . Aspects of hinge  10  that provide the balancing torque and closing torque are discussed further herein. 
       FIGS. 3-5  show an embodiment of a hinge  10  including a spring  24  and a pair of magnets including a first magnet  26  and a second magnet  28 . As shown a slider  40  extends axially out of an end  42  of housing  18  opposite input arm  20 . Spring  24  is positioned over and surrounding slider  40  and is captured between end  42  of housing and flange  44  on the opposite end of slider  40  therefrom. Slider  40  is operatively coupled with input arm by connector  46 , which is rotatably coupled with input arm  20  at a location spaced apart from the rotatable coupling between input arm  20  and housing  18 . Accordingly, when housing  18  is rotated relative to input arm  20  (such as by rotation of door  10 , to which housing  18  is attached) connector  46  moves relative to housing  18  in a direction away from end  42 , thereby moving slider  40  in the axial direction  48 , as shown in  FIG. 4 , in which housing  20   a  has been rotated relative to input arm  20  by approximately 25°. Such movement causes compression of spring  24 , thereby increasing the spring force proportionate to the spring coefficient thereof. The particular spring coefficient of spring  24  may vary according to the geometry of hinge  10 , including the amount of compression imparted on spring  24  by rotation of housing  18  relative to input arm  20 , as well as the weight of door  12  such that spring  24  applies the desired balancing torque about axis  38  (which may also include an allowance for internal friction among components). This operation is reversed during closing of door  12 . 
     As further shown in  FIGS. 3-5 , each of first magnet  26  and second magnet  28  are positioned within a chamber  50 , which is positioned within and connected to housing  18 . First magnet  26  is fixed within chamber  50 , and second magnet  28  is slidably received within chamber  50  so as to be moveable toward and away from first magnet  26 . A bar  52  is rigidly connected to second magnet  28  and bar  52  is coupled with input arm  20  by link  54 . Link  54  is rotatably coupled with bar  52  at an end thereof opposite second magnet  28  and is further rotatably coupled with input arm at a location remote from axis  38 . By this arrangement, rotation of housing  18  relative to input arm  20  causes second magnet  28  to move away from first magnet  26 . In the example shown in  FIGS. 3-5 , link  54  is rotatably coupled with input arm  20  at a location farther from axis  38  than the location of rotatable coupling of connector  46  with input arm  20 , which causes second magnet  28  to move through a distance greater than slider  40  for a given rotation of housing  18  relative to input arm  20 . 
     First magnet  26  and second magnet  28  are arranged so as to be mutually attracted to each other. As with magnets in general, the amount of mutual attraction between first magnet  26  and second magnet  28  depends on the distance therebetween, as well as the size and magnetic field strength of the magnets. In an example first magnet  26  and second magnet  28  can each have a magnetic field strength between about 1 T and 1.5 T. As shown in  FIG. 3 , the distance  56  between first magnet and second magnet  28  is zero when housing  18   c  is in the position that corresponds to a fully closed door  12   c  ( FIG. 2 ). Accordingly, in such a position, the mutual attraction between first magnet  26  and second magnet  28  is greatest in such a positioning of housing  18   c  relative to input arm  20 . This mutual attraction resists movement of second magnet  28  relative to first magnet  28  and, accordingly, rotational movement of housing  18   c  relative to input arm  20 . This additional force helps maintain door  12   c  in the closed position relative to body  16 , as described above, through the application of a closing torque about axis  38 . In an embodiment, the closing torque applied when housing  18   c  is in the closed state can be between about 60 N-m and 80 N-m. In a more particular embodiment, the closing torque in associated with the closed position of housing  18   c  can be about 70 N-m. 
     As shown in  FIGS. 3 and 4 , the above-describe coupling of slider  40  and second magnet  28  with input arm  20  is such that second magnet  28  moves away from first magnet simultaneously with compression of spring  24  by rotation of housing  18  relative to input arm  20 . Such movement of housing  18  is implemented by, for example, an opening movement of door  12  relative to body  16  of an associated appliance  14 , such as by downward rotation thereof. During initial rotation of housing  18 , first magnet  26  and second magnet  28  move away from each other but remain proximate to each other such that the mutual attraction therebetween remains appreciably present. In an example, the strength of first and second magnets  26  and  28 , as well as the proportion of movement of second magnet  28  relative to the rotation of housing  18  can be such that the mutual attraction between first magnet  26  and second magnet  28  remains appreciably present through an auto-closing range of motion. As illustrated in  FIG. 4 , such an auto-closing range of motion can be a rotational range of motion Θ a  of housing  18   a  relative to the closed position of housing  18   c  ( FIG. 3 ). In an embodiment, the auto-closing range of motion Θ a  can be through a rotation of between about 15° and 45°, and in a particular embodiment, a rotation of about 25°. Such a range can also apply to movement of door  12  relative to body  16 , as depicted by the position of door  12   a  in  FIG. 2 , which has been rotated to the end of auto-closing range Θ a . Such a range may correspond to a distance  56  between first magnet  26  and second magnet  28  of between 4 mm and 5 mm and in one embodiment about 4.13 mm. 
     The appreciable mutual attraction between first and second magnets  26  and  28  within auto-closing range Θ a  is such that an auto-closing torque is applied about axis  38 , acting through housing  18  to urge door  12  toward the closed position (door  12   c  in  FIG. 2 ). In an example, the auto-closing torque can be such that, if door  12  is moved from a position farther open than auto-closing range Θ a  (for example, within balancing range Θ b , as shown in connection with door  12   c  in  FIG. 2  and with housing  18   b  in  FIG. 5 ) into auto-closing range Θ a  and then let go, the auto-closing torque will act on door  12   a  to bring it to the closed position of door  12   c  ( FIG. 2 ). In a further example, if door  12   c  is moved from out of the closed position to a position within auto-closing range Θ a  and then released, the auto-closing torque will move door  12   a  back to the closed door  12   c  position. 
     Once housing  18  is moved outside of the auto closing range Θ a  toward the open door  12   o  position, shown in  FIG. 5  by movement of door  12  toward the open door  12   o  position ( FIG. 2 ), first magnet  26  and second magnet  28  will have been moved far enough apart such that the mutual attraction therebetween is no longer sufficient to produce an auto-closing torque. For example, a mutual attraction between first magnet  26  and second magnet  28  may be present, but the torque produced about axis  38  may not be sufficient to overcome the inertia of door  12   b  when positioned within the balancing range Θ a  between the auto-closing range Θ a  and the open door  12   o  position. Such a force may also be insufficient to produce a torque that is sufficient to overcome the resting friction between the various components of hinge  10 . As such, when housing  18   b  is in the balancing range Θ b , a selected position thereof may be maintained by the balancing torque applied by the spring  24  due to the increased compression thereof. When in the fully open door  12   o  position, such positioning of door  12   o  and housing  18   o  may be maintained by the mechanical limits of hinge  10  or by the geometry of appliance  14  or by a combination thereof with the balancing torque provided by spring  24 . 
     As shown in the graph of  FIG. 6 , the peak  56  of the auto-closing torque, represented by line  58  corresponds to the position of door  12   c  and housing  18   c  when closed and in which second magnet  28  contacts first magnet  26 . With movement of door  12   a  away from the closed position and toward the open door  12   o  position, the mutual attraction between first magnet  26  and second magnet  28  decreases logarithmically with the corresponding movement of second magnet  28  away from first magnet  26 . During this movement, movement of slider  40  begins to compress spring  24  such that the balancing torque, represented by line  60 , which is combined with auto closing torque  58  to achieve a total torque  62 . 
     The transition Θ t  from the auto-closing range Θ a  to the balancing range Θ b  occurs when the torque provided by the attraction between first magnet  26  and second magnet  28  reaches a minimum level  64 . In an example, such a minimum level  64  may be such that the total torque  62  is only sufficient to balance against the increasing opposite torque provided by the weight of door  12  as the moment arm thereof increases in horizontal length. Continued compression of spring  24  results in an increase in balancing torque  60  that corresponds to the increasing torque (e.g. between 0 and 30 N-m) applied about axis  38  by door  12   b  by selection of a spring  24  with a coefficient that corresponds to the movement of slider  40  achieved by the geometry of hinge  10 . The combination of the torques provided by the balancing torque  60  and the auto-closing torque  58 , thusly, provides the movement characteristics for door  12  described above. In an embodiment, the auto-closing torque at a point  66  where door  12  is at the transition angle Θ t  can be about 3 N-m or less and, in one embodiment can be about 2.7 N-m. Continued movement of door  12   b  within the balancing position can further decrease the auto-closing torque below the level at the transition angle Θ t . 
       FIGS. 7-9  show another embodiment of a hinge  110  that can carry out the auto-closing and balancing functionality described above with respect to  FIGS. 1-6 . As with the previous embodiment, hinge  110  includes including a spring  124  and a pair of magnets including a first magnet  126  and a second magnet  128 . Slider  140  extends axially out of end  142  of housing  118  opposite input arm  120 . Spring  124  is positioned over and surrounding slider  140  and is captured between end  142  of housing and flange  144  on the opposite end of slider  140  therefrom. Slider  140  is operatively coupled with input arm  120  by connector  146 , which is rotatably coupled with input arm  120  at a location spaced apart from the rotatable coupling between input arm  120  and housing  118 . Accordingly, when housing  118  is rotated relative to input arm  120  (such as by rotation of door  12 , to which housing  118  may be attached in a manner similar to that of housing  18 , described above) connector  146  moves relative to housing  118  in a direction away from end  142 , thereby moving slider  140  in the axial direction  148 , as shown in  FIG. 8 , in which housing  118   a  has been rotated relative to input arm  120  by approximately 25°. Such movement causes compression of spring  124 , thereby increasing the spring force proportionate to the spring coefficient thereof. The particular spring coefficient of spring  124  may vary according to the geometry of hinge  110 , including the amount of compression imparted on spring  124  by rotation of housing  118  relative to input arm  120 , as well as the weight of door  112  such that spring  124  applies the desired balancing torque about axis  138  in a manner similar to that described above, including with reference to  FIG. 6 . This operation is reversed during closing of door  12 . 
     As further shown in  FIGS. 7-9 , first magnet  126  is fixed within housing  118 , and second magnet  128  is fixed with slider  140  so as to be moveable with slider  140  within housing  118  and moveable toward and away from first magnet  126 . By this arrangement, rotation of housing  118  relative to input arm  120  causes second magnet  128  to move away from first magnet  126  by the same distance and the compression of spring  124 . As shown in  FIG. 7 , the distance  156  between first magnet  126  and second magnet  128  is zero when housing  118  is in the position that corresponds to a fully closed door  12   c  ( FIG. 2 ) such that the force provided by the mechanism (i.e. the closing force) is provided by both the spring and the magnets. Initially during opening of door  12   a  corresponding to the movement of housing  118   a  within auto-closing range Θ s , shown in  FIG. 8 , the first magnet  126  and second magnet  128  continue to contribute an appreciable auto-closing torque, as described above with respect to  FIG. 6  (and with quantities that can be the same as or similar to those described above with respect to hinge  10  in  FIGS. 3-5 ). As also described above, movement of door  12   b  to within balancing range Θ b  results in the auto-closing torque being lower than that needed to implement auto-closing of door  12 , at which point spring  124  and the torque about axis  138  provided thereby continues to balance against the weight torque of door  12 , thereby maintaining a selected position of door within balancing range Θ b  up to the fully open housing  118   o  position (as shown in  FIG. 9 ). 
     It will be understood by one having ordinary skill in the art that construction of the described disclosure and other components is not limited to any specific material. Other exemplary embodiments of the disclosure disclosed herein may be formed from a wide variety of materials, unless described otherwise herein. 
     For purposes of this disclosure, the term “coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated. 
     It is also important to note that the construction and arrangement of the elements of the disclosure as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations. 
     It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting. 
     It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present disclosure, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.