Abstract:
The present teachings disclose a wire mesh heater including: a wire mesh element having a surface area including a non-contact area and a contact area along at least 50% of a wire mesh element length; a primary conductor including a slit having a contact surface, wherein the contact area contacts the contact surface to provide an electrical connection between the wire mesh element and the primary conductor. In some embodiments, the primary conductor is welded to the wire mesh element, wherein the contact area contacts the contact surface to provide an electrical connection between the wire mesh element and the primary conductor. In some embodiments, an elastic is stretched and secured tautly under tension prior to operation of the wire mesh heater, and the elastic keeps the wire mesh element tautly under tension during operation of the wire mesh heater.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a 371 of International Patent Application No. PCT/US2016/013183 filed Jan. 13, 2016, which claims the benefit of U.S. Provisional Application No. 62/102,612, filed Jan. 13, 2015, and U.S. Provisional Application No. 62/218,578, filed Sep. 15, 2015, all of which are incorporated in their entirety by reference for all purposes as if fully set forth herein. 
     
    
     FIELD 
       [0002]    The present disclosure teaches a wire mesh energy transfer system that enables an uninterrupted or long term consecutive heating of a wire mesh for use in high speed heating applications. In particular, the system includes a primary conductor having a primary bond to a wire mesh heater and a secondary conductor to allow for the efficient transfer of electrical energy to the electrode and from there to the wire mesh heater. Aspects of a wire mesh heating system and oven may be found in U.S. Pat. Nos. 8,126,319, 8,145,548 and 8,498,526, and U.S. Application Nos. 13/284,426, 12/345,939, 13/405,975, 13/430,189, and 61/916,705 (provisional application) the contents of which are incorporated herein by reference in their entirety. 
       BACKGROUND 
       [0003]    U.S. Pat. No. 8,498,526 to De Luca discloses using stored energy to energize a wire mesh heating element to heat an item within a heating cavity. Temperatures inside the heating cavity reach the temperature of the heating element itself very quickly, in some cases up to 1500° C. When the one or more elements are used without interruption, the heating cavity and wire mesh element holders holding the wire mesh heating element heat up. Without limitation, it is theorized that the wire mesh element holders heat due to heat from the wire mesh heating element and from transferring electrical energy at contact points. It is also theorized that the wire mesh heating element holders increase in temperature faster than the heating cavity. 
         [0004]    A strong and stable electrical connection to the wire mesh is needed to provide even heating in the radiant oven and to extend the life of the wire mesh heating element. When an electrical connection to the element is not uniform, for example, when contact pressure between the wire mesh element holder and the wire mesh element is uneven then the electrical current tends to travel through or concentrates in the contact area where the contact is better. As such, the concentrated area of contact becomes hotter than the remaining area of the wire mesh element or the wire mesh element holder, and a failure point is created. The use of materials that are both strong at high temperatures, but are also electrically conductive is a difficult match to achieve at a reasonable price point. Many such materials, for example, aluminum, also melt well below the operating temperature of the wire mesh element. 
         [0005]    Tensioning of a wire mesh heating element is also more difficult than the tensioning of a single wire strand as the expansion and contraction of the element can vary if the heating is uneven or the mesh is oriented in such a fashion that could create zones of greater expansion. This is especially true if the element is oriented as further described by De Luca in co-pending PCT application PCT/US14/70601 entitled “A Continuous Renewal System for a Wire Mesh Heating Element and a Woven Angled Wire Mesh”, filed Dec. 16, 2014. The high rate cycling of the mesh further increases the probability of a mesh failure with an unevenly tensioned mesh. The use of a warped element in the heating or cooking chamber can cause uneven heating or cooking of the item. 
         [0006]    In the prior art, changing wire mesh heating elements is difficult, however, it is needed for many commercial ovens. The use of fasteners that are tightened to a precise torque value is often difficult to achieve in the field, for example, for restaurants, where a lack of necessary training may be found. 
       SUMMARY 
       [0007]    The present teachings provide embodiments of heating system and methods, and features thereof, which offer various benefits. The system can employ multiple electrodes, systems, operations, and the like to promote safe, efficient, and effective use of the devices and methods disclosed herein. 
         [0008]    The present teachings disclose a wire mesh heater including: a wire mesh element having a surface area including a non-contact area and a contact area along at least 50% of a wire mesh element length; a primary conductor including a slit having a contact surface, wherein the contact area contacts the contact surface to provide an electrical connection between the wire mesh element and the primary conductor. 
         [0009]    The present teachings disclose a wire mesh heater including: a wire mesh element having a surface area including a non-contact area and a contact area along at least 50% of a wire mesh element length; a primary conductor welded to the wire mesh element, wherein the contact area contacts the contact surface to provide an electrical connection between the wire mesh element and the primary conductor. 
         [0010]    The present teachings disclose a wire mesh heater including: a wire mesh element having a surface area including a non-contact area and a contact area along at least 50% of a wire mesh element length; a conductor in electrical contact with the wire mesh; an elastic bonded to at least one edge of the wire mesh element; and a fastener to secure the elastic, wherein the contact area contacts the conductor and the elastic is stretched and secured tautly under tension to the fastener prior to operation of the wire mesh heater, and the elastic keeps the wire mesh element tautly under tension during operation of the wire mesh heater. 
         [0011]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0012]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention. 
           [0013]      FIG. 1A  is an isometric view of an unassembled wire mesh heater including a wire mesh element and a primary conductor according to various embodiments. 
           [0014]      FIG. 1B  is an isometric view of an assembled wire mesh heater including a wire mesh element and a primary conductor according to various embodiments. 
           [0015]      FIG. 2A  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. 
           [0016]      FIG. 2B  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. 
           [0017]      FIG. 3A  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. 
           [0018]      FIG. 3B  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. 
           [0019]      FIG. 3C  is an enlarged isometric view of a wire mesh heater assembly of  FIG. 3A  including a connection point between the primary conductor and a secondary conductor according to various embodiments. 
           [0020]      FIG. 4A  is an isometric view of a tensioning system based on multiple tensioned points and a partially segmented primary conductor according to various embodiments. 
           [0021]      FIG. 4B  is an isometric view of a tensioning system based on multiple tensioned points and a fully segmented primary conductor according to various embodiments. 
           [0022]      FIG. 5A  and  FIG. 5B  are isometric views of an oven cavity including a wire mesh heater assembly disposed therein according to various embodiments. 
           [0023]      FIG. 5C  is an enlarged isometric view of an oven cavity including a wire mesh heater assembly and a flexible braided connection to a secondary conductor according to various embodiments. 
           [0024]      FIG. 6A  and  FIG. 6B  are isometric views of a cooking cavity with heat shielding to thermally protect the primary conductor and an elevator usable to alter the distance between two wire mesh heater assemblies according to various embodiments. 
           [0025]      FIG. 7  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
           [0026]      FIG. 8  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
           [0027]      FIG. 9A  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
           [0028]      FIG. 9B  is a logical view of a wire mesh heater assembly, according to various embodiments. 
           [0029]      FIG. 10  is an isometric of a wire mesh and microwave heater, according to various embodiments. 
       
    
    
       [0030]    Throughout the drawings and the detailed description, unless otherwise described, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. The relative size and depiction of these elements may be exaggerated for clarity, illustration, and convenience. 
       DESCRIPTION 
       [0031]    The present teachings disclose efficiently transferring electrical energy to a wire mesh heating element. In exemplary embodiments, the transfer is evenly distributed over a breadth or length of the wire mesh. This may reduce the stress induced in the wire mesh, and reduce the heat being generated during the electrical energy transfer. The present teachings may evenly distribute any heat being generated during the electrical energy transfer. By reducing the heating and/or more evenly distributing the heat, the mean time between failures of the wire mesh heater may be increased. 
         [0032]    The present teachings disclose a heating element system able to operate semi-continuously or continuously at high temperatures. The present teachings also disclose constant tensioning of a wire mesh heating element during use so that the element as a whole remains flat. The present teachings also disclose a wire mesh heating element that can operate in a heating cavity in a semi-continuous or continuous mode and that can be replaced easily. 
         [0033]    In exemplary embodiments, a wire mesh heating assembly may include a primary conductor directly attached to the wire mesh heating element, and a secondary conductor or holder to secure the primary conductor through which the electrical current can flow. In some embodiments, the primary conductor may include a primary conduction rod or electrode. 
         [0034]    According to various embodiments, the primary conductor may be continuous or fully or partially segmented. The primary conductor may contact a length of the wire mesh element. 
         [0035]    The secondary conductor may tension, stretch or keep taut the wire mesh heating element in operation. In some embodiments, the secondary conductor may provide an adjustable tension for the wire mesh heating element in operation. The secondary conductor may include multiple tension points, a heat shield protection, and a latch or the like to provide ease of gripping and release of the primary conductor. 
         [0036]    In exemplary embodiments, a flexible or movable electrical connection may connect an electrical energy source to the primary conductor. The flexible or movable electrical connection may include a stranded wire or telescoping nested tubes attached to the secondary conductor. 
         [0037]      FIG. 1A  is an isometric view of an unassembled wire mesh heater including a wire mesh element and a primary conductor according to various embodiments. An unassembled wire mesh heater  100 ′ may include a wire mesh element  102  and a primary conductor  104 . The wire mesh element  102  may have a length L M , for example, along an X-axis. The wire mesh element  102  may have a width W M , for example, along a Y-axis. The wire mesh element  102  may be planar. The wire mesh element  102  may be planar after application of a force or tension along the X-axis and the Y-axis. A surface of the wire mesh element  102  may be divided into a contact area  106  and a non-contact area  108 . The non-contact area  108  may include a majority of the surface of the wire mesh element  102 . The contact area  106  may be separated from the non-contact area  108  by an imaginary axis  110 . The non-contact area  108  may have a width W NC  that is smaller than the width W M  of the wire mesh element  102 . The non-contact area  108  may be adjacent to the contact area  106 . In some embodiments, the non-contact area  108  may be surrounded by two contact areas  106 . The primary conductor  104  may have a length L PC  and a width W PC . The primary conductor  112  may include a slit  112 . The slit  112  may run along the whole W PC  or a portion thereof. The slit  112  may run along the whole L PC  or a portion thereof. In some embodiments, the length L PC  may be greater than or equal to the length L M . 
         [0038]      FIG. 1B  is an isometric view of an assembled wire mesh heater including a wire mesh element and a primary conductor according to various embodiments. An assembled wire mesh heater  100  may include the wire mesh element  102  and the primary conductor  104 . In the assembled wire mesh heater  100  the contact area  106  of  FIG. 1  maybe secured in the slit  112  along the imaginary axis  110 . The securing of the wire mesh heater  100  in the slit  112  may be bonded with a press. In some embodiments, the assembled wire mesh heater  100  is formed by assembling the unassembled wire mesh heater  100 ′ of  FIG. 1A . 
         [0039]      FIG. 2A  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. A wire mesh heater assembly  200  may include an assembled wire mesh heater  100  including a wire mesh element  102  and a primary conductor  104 . The wire mesh heater assembly  200  may include a first portion  202  of a secondary conductor  210  that engages with a second portion  204  of the secondary conductor  210 . The first portion  202  of the secondary conductor  210  may connect to the second portion  204  of the secondary conductor  210  at a hinge  206  or the like about which the first portion  202  can pivot to join with the second portion  204 . 
         [0040]    The second portion  204  of the secondary conductor  210  may include a trough or void  208  to trap a portion of the primary conductor  102 . The first portion  202  of the secondary conductor  210  may include a trough or void (not shown), similar to trough or void  208 , to trap a portion of the primary conductor  102 . The second portion  204  of the secondary conductor  210  may include a fastener  212  to secure the first portion  202  and the second portion  204 . 
         [0041]      FIG. 2B  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments. The wire mesh heater assembly  200  may be secured by disposing closing the first portion  202  and securing it with the fastener  212 . According to various embodiments, in  FIG. 2B  the hinge  206  is in a closed position such that the first portion  202  joins or meets the second portion  204  along a majority of a length of the first portion  204 . 
         [0042]      FIG. 3A  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments.  FIG. 3B  is an isometric view of a wire mesh heater assembly including a wire mesh element and a primary conductor according to various embodiments.  FIG. 3C  is an enlarged isometric view of a wire mesh heater assembly of  FIG. 3A  including a connection point between the primary connection rod and a secondary connector according to various embodiments. 
         [0043]    A wire heater assembly  300  may include a wire mesh element  302 , a primary conductor  320  to secure the wire mesh element  302  in a slit  312  (see  FIG. 3C ), a first portion  306  of a secondary conductor, a fastener  308 , and a groove  310  in a second portion  304  of the secondary conductor to secure the primary conductor  320  when the fastener  308  is disposed to secure the first portion  306  to the second portion  304 . A length L G  of the slit  312  (see  FIG. 3C ) can be less than a diameter or cross-width of the primary conductor  320 . The wire mesh hearing element  302  may be secured in the slit  312 . The slit  312  may be crimped to secure the write mesh hearing element  302 . The crimping may be performed by pressing the slit  312  closed, for example, with a press. In some embodiments, the second portion  306  of the secondary conductor can be disposed in a frame  316 . As such, the frame  316  may form one pole of an electrical circuit energizing the wire mesh hearing element  302 . 
         [0044]    In some embodiments, an electrical cable connector  314  can extend from the secondary conductor. The frame  316  can pivot about the electrical cable connector  314 . In some embodiments, the electrical cable connector can be disposed on the second portion  304  of the secondary conductor (see  FIG. 3B ). The second portion  304  of the secondary conductor may be electrically insulated from the frame  316  by insulating washers (not shown). 
         [0045]      FIG. 4A  is an isometric view of a tensioning wire mesh heater assembly based on multiple tensioned points and a partially segmented primary conductor according to various embodiments. 
         [0046]    A tensioning wire mesh heater assembly  400  may include a wire mesh heater  402  and a first conductor assembly  420  including multiple tensioning points  432  connected via springs  430  to a segmented secondary conductor  434 . The first conductor assembly  420  may include a primary conductor  412  with a slit therein. In some embodiments, the tensioning wire mesh heater assembly  400  may include a second conductor assembly  422  including a primary conductor  424  including a slit. The second conductor assembly  422  may be fixedly held at a first end of an oven cavity. The multiple tensioning points  432  may be fixedly held at a second end opposite the first end of the oven cavity. As the wire mesh heater  402  stretches due, for example, to the stress of repeated heating of the oven, the springs  430  may keep the wire mesh heater  402  taut. According to various embodiments, the segmented secondary conductor  434  of the first conductor assembly  420  may be connected to one pole of an electrical power source, and the second conductor assembly  422  may be connected to another pole of the electrical power source. 
         [0047]      FIG. 4B  is an isometric view of a tensioning system based on multiple tensioned points and a fully segmented primary conductor according to various embodiments. 
         [0048]    A tensioning wire mesh heater assembly  400 ′ may include a wire mesh heater  402 ′ and a first conductor assembly  420 ′ including multiple tensioning points  432 ′ connected via springs  430 ′to a segmented secondary conductor  434 ′. The first conductor assembly  420  may include a segmented primary conductor  412 ′ with a slit therein. The segmented primary conductor  412 ′ may be segmented by a cut  436  across the full or partial width of the segmented primary conductor  412 ′. In some embodiments, the tensioning wire mesh heater assembly  400  may include a second conductor assembly  422 ′ including a primary conductor  424 ′ including a slit. The second conductor assembly  422 ′ may be fixedly held at a first end of an oven cavity. The multiple tensioning points  432 ′ may be fixedly held at a second end opposite the first end of the oven cavity. As the wire mesh heater  402 ′ stretches due, for example, to the stress of repeated heating of the oven, the springs  430 ′ may keep the wire mesh heater  402 ′ taut. According to various embodiments, the segmented secondary conductor  434 ′ of the first conductor assembly  420 ′ may be connected to one pole of an electrical power source, and the second conductor assembly  422 ′ may be connected to another pole of the electrical power source. 
         [0049]      FIG. 5A  and  FIG. 5B  are isometric views of an oven cavity including a wire mesh heater assembly disposed therein according to various embodiments. 
         [0050]      FIG. 5C  is an enlarged isometric view of an oven cavity including a wire mesh heater assembly and a flexible braided connection to a secondary conductor according to various embodiments. 
         [0051]      FIG. 6A  and  FIG. 6B  are isometric views of a cooking cavity with heat shielding to thermally protect the primary conductor and an elevator usable to alter the distance between two wire mesh heater assemblies according to various embodiments. 
         [0052]    An oven  600  may include a cooking cavity  602 . A wall  604  may be disposed as a heat shield. The wall  604  may thermally isolate or protect a primary conductor  606  from heat generated by a wire mesh heater assembly  608 . An elevator  610  may alter a gap or distance between two wire mesh heater assemblies  608 , according to various embodiments. 
         [0053]      FIG. 7  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
         [0054]    The wire mesh heater assembly  700  may include a wire mesh  702  secured to a primary conductor  704  by a solder, swage or weld  712 . The primary conductor  704  of the wire mesh heater assembly  700  may be secured by a secondary conductor  706  and  708 . Secondary conductor  7678  may be covered or coded with an insulative material  710 . 
         [0055]      FIG. 8  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
         [0056]    A wire mesh  800  can be provided with a bent edge  802  along a periphery of the wire mesh. In some embodiments, the wire mesh  800  may be provided with a second bent edge (not shown) along an edge opposite the bent edge  802 . The bent edge  802  may reduce a flex produced in the wire mesh  800  when the wire mesh  800  is heated to high temperatures. 
         [0057]      FIG. 9A  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
         [0058]      FIG. 9B  is a logical view of a wire mesh heater assembly, according to various embodiments. 
         [0059]    The wire mesh assembly  900  may include the wire mesh  902  and a thermal insulative material  904  disposed along an edge of the wire mesh  902 . The insulative material  904  may include a fastener  910  that can be secured in a wire mesh heater. The wire mesh assembly  900  can be disposed over two conductors  906 ,  908  to provide a heat zone  926  between the two conductors  906 ,  908 . The two conductors  906 ,  908  can be energized by a voltage source  920  in series with a switch  922 . The fastener  910  can be secured to a chassis of the wire mesh heater (not shown) using a fastener holding device  924 . In some embodiments, the thermal insulating material  904  can include silicon. The wire mesh assembly  900  can be fastened under tension (tautly). 
         [0060]      FIG. 10  is an isometric of a wire mesh and microwave heater, according to various embodiments. 
         [0061]    A wire mesh and microwave heater  1000  may include the wire mesh element  1002 , a magnetron  1004  and a high wattage power supply  1006  including a stored energy device. The wire mesh element  1002  can be disposed in a heating cavity  1008  where radiation from the magnetron  1004  impinges on the wire mesh element  1002 . Both the magnetron  1004  and the wire mesh element  1002  may be operated simultaneously. Power in excess of the capacity of the AC power line may be provided by the stored energy device includes with the high wattage power supply  1006 . 
         [0062]      FIG. 11A  is an isometric view of a wire mesh heater assembly, according to various embodiments. 
         [0063]      FIG. 11B  is a logical view of a wire mesh heater assembly, according to various embodiments. 
         [0064]    A wire mesh assembly  1100  may include the wire mesh  1102  and an elastic  1104 . The wire mesh assembly  1100  may include a secondary conductor  1110 . The elastic  1104  may be secured, fastened or joined to one or more edges of the wire mesh  1102  to form a bendable closed loop  1130 . The elastic  1104  maybe fastened to one or more edges of the wire mesh  1102  using a fastener (not shown) such as a bolt and nut, or the like. The elastic  1104  maybe secured or joined to one or more edges of the wire mesh  1102  by embedding one of the edges in the elastic  1104 . The closed loop  1130  may be disposed over two conductors  1106 ,  1108  to provide a heat zone  1126  between the two conductors  1106 ,  1108  (primary conductors). In exemplary embodiments, the secondary  1110  contacts one or more of the two conductors  1106 ,  1108 . The two conductors  1106 ,  1108  can be energized by a voltage source (not shown) in series with a switch (not shown). 
         [0065]    The elastic  1104  may be a springy material able to withstand high temperatures, for example, silicone. The wire mesh  1102  may be secured or fastened to the secondary conductor  1110 . The secondary conductor  1110  may be movably disposed over one or more of the two conductors  1106 ,  1108  in order to provide a high-performing electrical contact between the wire mesh  1102  and one or more of the two conductors  1106 ,  1108 . In some embodiments, a solder, swage, weld or the like may be used to secure the wire mesh  1102  to the secondary conductor  1110 . The wire mesh assembly  1100  can be disposed under tension (tautly) over the two conductors  1106 ,  1108 . In some embodiments, the two conductors  1106 ,  1108  may be immovably secured in a holder  1142 . In some embodiments, one of the two conductors  1106 ,  1108  may be movably secured in the holder  1142 , while the other of the two conductors  1106 ,  1108  may be immovably secured in the holder  1142 . A heat shield  1144  may be disposed between the heat zone  1126  and the elastic material  1104 . 
         [0066]    The examples presented herein are intended to illustrate potential and specific implementations. It can be appreciated that the examples are intended primarily for purposes of illustration for those skilled in the art. The diagrams depicted herein are provided by way of example. There can be variations to these diagrams or the operations described herein without departing from the spirit of the invention. For instance, in certain cases, method steps or operations can be performed in differing order, or operations can be added, deleted or modified.