Abstract:
An air duct system may employ an HVAC case having an exit air duct and a return air duct, a windshield with an interior surface, an approximately vertical duct, and a horizontal duct. Ducts mount to the windshield and each define an interior passageway with the interior surface of the windshield and a second, return air, passageway. The interior passageway may receive air from the exit air duct and the second passageway may return air to the return air duct. End chambers of each duct reverse air direction 180 degrees. Air of each interior passageway may warm an adjacent area of the windshield that forms part of each interior passageway and a windshield wiper. The first air duct interior passageway may warm a windshield area coincident with a maximum non-park wiper position and the second air duct interior passageway may warm a windshield area coincident with a wiper park position.

Description:
FIELD 
       [0001]    The present disclosure relates to a heating, ventilating and air-conditioning system and associated air ducts used to warm a windshield and wiper blades. 
       BACKGROUND 
       [0002]    This section provides background information related to the present disclosure which is not necessarily prior art. Modern vehicles such as automobiles may be equipped with a windshield wiping system that to varying degrees of effectiveness, wipes water, snow, ice and other debris from an exterior surface of a windshield. However, such a system is not without its limitations for removing such snow and ice from an exterior surface of the windshield. An effective system for melting such ice and snow from specific areas of the windshield to prevent obstruction with one or more windshield wipers is needed. 
       SUMMARY 
       [0003]    This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. An apparatus to warm a windshield may employ an HVAC case, unit or assembly having an exit air duct and a return air duct, a windshield having an interior surface, and an approximately vertical duct. The vertical duct may entail a first approximately vertical wall arranged next to the windshield to define an interior passageway with the interior surface of the windshield, and a second approximately vertical wall arranged next to the interior wall to define an exterior passageway with the first wall. The interior passageway may receive air from the exit air duct and the exterior passageway may deliver air to the return air duct. The approximately vertical duct may define an end chamber where flowing air reverses direction 180 degrees, or whatever angle is necessary to return air within the vertical duct. The horizontal duct, or approximately horizontal duct, may entail a first horizontal wall arranged next to the windshield and defining a horizontal, or approximately horizontal, interior passageway with the interior surface of the windshield, and an second horizontal wall arranged next to the first horizontal wall and defining an horizontal exterior passageway with the first horizontal wall, wherein the horizontal interior passageway receives air from the exit air duct and the horizontal exterior passageway delivers air to the return air duct. The horizontal duct may define an end chamber where flowing air reverses direction 180 degrees within the horizontal duct. An A-pillar, or vehicle body structure, within which the windshield may partially mount, may be parallel to or approximately parallel to the vertical duct. A heated zone of the windshield heated by the approximately vertical duct may be completely beside the A-pillar, or body component. A manifold may divide air from the HVAC case to the approximately vertical duct and the horizontal duct, and combine return air from the approximately vertical duct and the horizontal duct before the air is returned to the HVAC case, unit or assembly. 
         [0004]    In another arrangement, an apparatus for warming a windshield may employ an HVAC case having an exit air duct and an inlet air duct, a windshield having an interior surface, an approximately vertical duct and a horizontal or approximately horizontal duct. The approximately vertical duct may employ a first approximately vertical wall arranged next to the windshield and define an interior passageway with the interior surface of the windshield, and a second approximately vertical wall arranged next to the first approximately vertical wall that may define an exterior passageway with the first wall. The interior passageway may receive air from the exit air duct and the exterior passageway may return or deliver air to the return air duct. The horizontal duct may employ a first horizontal wall arranged next to the windshield and define a horizontal interior passageway with the interior surface of the windshield. A second horizontal wall may be arranged next to the first horizontal wall and define a horizontal exterior passageway with the first horizontal wall. The horizontal interior passageway may receive air from the exit air duct and the horizontal exterior passageway may deliver air to the return air duct. 
         [0005]    A manifold may define a vertical branch and a horizontal branch, the vertical branch may connect to the approximately vertical duct and the horizontal branch may connect to the horizontal duct. The manifold may further define a first chamber in which air moves away from the HVAC case and a second chamber in which air moves toward the HVAC case. The first chamber of the manifold may direct air into the approximately vertical duct and the horizontal duct. The approximately vertical duct may define an end chamber where flowing air reverses direction 180 degrees, and similarly, the horizontal duct may define an end chamber where flowing air reverses direction 180 degrees. The second approximately vertical wall and the first approximately vertical wall may be connected together along parallel longitudinal edges, and the second horizontal wall and the first horizontal wall are connected together along parallel longitudinal edges. 
         [0006]    In yet another configuration, an apparatus to warm a windshield may employ an HVAC case having an exit air duct and an inlet air duct, a windshield having an interior surface, a first air duct and a second air duct. The first air duct may employ a first air duct interior longitudinal wall arranged next to the windshield and may define a first air duct first interior passageway with the interior surface of the windshield. A first air duct exterior longitudinal wall may be arranged partially against the first air duct interior longitudinal wall to define a first air duct exterior passageway. The second air duct may employ a second air duct interior longitudinal wall arranged next to the windshield to define a second air duct interior passageway with the interior surface of the windshield. A second air duct exterior longitudinal wall may be arranged in part against the second air duct interior longitudinal wall to define a second air duct exterior passageway with the second air duct interior longitudinal wall. 
         [0007]    An air manifold may define a first chamber and a second chamber. The first chamber may direct air into the first air duct interior passageway and the second air duct interior passageway and receive air from the exit air duct. The second chamber may receive air from first air duct exterior passageway and the second air duct exterior passageway and direct the air into the inlet air duct. The first air duct may define an end chamber where flowing air reverses direction 180 degrees, and similarly, the second air duct may define an end chamber where flowing air reverses direction 180 degrees. The first air duct and the second air duct are mounted to the windshield, which may be a boundary of air ducts and a wall of a chamber of either duct where air is reversed in direction. The first air duct interior longitudinal wall and the first air duct exterior longitudinal wall may be connected together along parallel longitudinal or lengthwise edges, and the second air duct interior longitudinal wall and the second air duct exterior longitudinal wall may be connected together along parallel longitudinal or lengthwise edges. The first air duct may be located parallel to an A-pillar within which or to which the windshield may be secured. The first air duct interior passageway may warm an area of the windshield coincident with a maximum non-park position (a position of the wiper closest to the A-pillar) of a windshield wiper. The second air duct interior passageway may warm an area of the windshield coincident with or surrounding a horizontal or park position of the windshield wiper. 
         [0008]    Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0009]    The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
           [0010]      FIG. 1  is a perspective view of a vehicle depicting a location of ducting in accordance with the present disclosure; 
           [0011]      FIG. 2  is a front view of a vehicle depicting a location of ducting relative to windshield wipers in accordance with the present disclosure; 
           [0012]      FIG. 3  is a view through a windshield from an interior of a vehicle depicting a location of ducting on an interior of the windshield in accordance with the present disclosure; 
           [0013]      FIG. 4  is a cross-sectional view of a windshield and adjacent ducting in accordance with the present disclosure; 
           [0014]      FIG. 6  is a cross-sectional view of an HVAC case depicting an inlet duct and HVAC case with an evaporator and heater core in accordance with the present disclosure; 
           [0015]      FIG. 5  is a side view of how air returning to an HVAC case may be conditioned and warmed in accordance with the present teachings; and 
           [0016]      FIG. 7  is a perspective view of a manifold to distribute air to and receive air from vertical and horizontal ducts adjacent a windshield. 
       
    
    
       [0017]    Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
       DETAILED DESCRIPTION 
       [0018]    Example embodiments will now be described more fully with reference to  FIGS. 1-7  of the accompanying drawings.  FIG. 1  is a perspective view of a vehicle  10 , such as an automobile, depicting a location of wiper blades  14 ,  16  in a low position  12 . Low position  12  may be a horizontal or approximately horizontal low park position when blades  14 ,  16  are turned off and not operating or a maximum pivot, low operating position when blades  14 ,  16  are turned on or operating. Each of driver wiper  14  and passenger wiper  16 , may be biased toward and rest against an exterior surface of windshield  18 . When in position  12 , driver side wiper  14  may reside within an approximately horizontal or horizontal zone  20 , which may be a heated zone of windshield  18 . Moreover, wiper  14  may pass within an approximately vertical or vertical zone  22 , which may also be a heated zone of windshield  18 . Zones  20 ,  22  may be heated from an interior surface of windshield  18 , as will be further described later. 
         [0019]    With reference now including  FIG. 3 , heated zones  20 ,  22  of windshield  18  become heated by ductwork inside a vehicle passenger compartment that is connected to a heating, ventilating and air conditioning (“HVAC”) system of vehicle  10 . An approximately vertical or vertical duct  24 , hereinafter referred to as “vertical duct” and an approximately horizontal or horizontal duct  26 , hereinafter referred to as “horizontal duct” may be fluidly connected to HVAC system  28  to deliver warmed and conditioned air through vertical duct  24  and horizontal duct  26 . With reference including  FIG. 6 , HVAC system  28  may employ an external case  30  within which an evaporator  32 , a heater core  34 , a motor  36 , and a fan  38  may reside. At fresh/re-circulating inlet  40 , air  41  may enter due to a drawing force of rotating fan  38  which is turned by electric motor  36 . Air  41  may then be forced into foot duct  42 , for example, and into feeder duct  44  as conditioned air  46 . Foot duct  42  is being referred to as such, although another duct may be suitable. Feeder duct  44  may be an HVAC case exit duct, such that air  46  may exit and be directed into vertical duct  24  and horizontal duct  26 . Upon passing through one or both of vertical duct  24  and horizontal duct  26 , air  46  then is directed back to HVAC case  30  where it is re-conditioned and/or warmed and again directed out of HVAC case  30 .  FIGS. 3 and 6  depict one arrangement of evaporator  32 , heater core  34 , motor  36 , duct feeder pipe  44  and return air duct  48  although other arrangements are conceivable. Regardless, air  46  returning to HVAC case  30  may be returned to HVAC case  30  to pass through evaporator  32  and heater core  34  as required by an operator of a vehicle using HVAC controls in an interior compartment of a vehicle  10 . 
         [0020]    Continuing with  FIGS. 3 and 4 , details of vertical duct  24  will be presented. Vertical duct  24  may be located against an interior surface  52  windshield  18  such that a seal  50  is adhered to an interior surface  52  of windshield  18 . Seal  50  may prevent the escape of air between windshield  18  and an interior wall  54  of vertical duct  24 . Interior wall  54  and an exterior wall  56  form part of vertical duct  24 . Interior wall  54  may be called such because it is close to an interior surface  52  of windshield  18 ; similarly, exterior wall  56  may be called such because it is farther from interior surface  52  of windshield  18  than interior wall  54 . Interior wall  54  may be formed to adhere to seals  50  and define an interior air passageway  58  between interior wall  54  and interior surface  52  of windshield  18 . Exterior wall  56  may be formed to adhere to interior wall  54  and define an exterior air passageway  60  with interior wall  54 . Thus, vertical duct  24 , in conjunction with interior surface of windshield  18 , defines two flow paths to direct air from and to HVAC case  30 . More specifically, air passage  58  is defined between interior surface  52  and interior wall  54  and is first to receive warmed air from HVAC case  30  from air conditioned by evaporator  32  and warmed by heater core  34 . Upon air  46  passing through air passageway  58  against interior surface  52  of windshield  18 , air warms windshield  18  and reaches an end  62  of interior wall  54  of vertical duct  24  and flows around end  62  and into air passage  60 . At end  62  of vertical duct  24 , a chamber may exist within which air is directed into exterior passageway  60  at 180 degrees in the opposite direction as in air passage  58 . Once in exterior passageway  60 , air  46  is directed back to return air duct  48  so that air  46  may be delivered to HVAC case  30 , where it may again be conditioned and warmed. Vertical duct  24  may reside beside an A-pillar  25  of a driver side of vehicle  10  such that vertical duct  24  may be parallel to or approximately parallel to vertical duct  24 . 
         [0021]      FIG. 4  depicts a cross-section of vertical duct  24 . More specifically, when wiper blade  14  is in an upright or nearly vertical position, such as when wiper  14  is a maximum pivot point when operating, as depicted in  FIG. 4 , an unobstructed path upon exterior surface  76  of windshield  18  will be provided by operation of vertical duct  24 . More specifically, exterior surface  76  will be unobstructed by accumulated snow and ice  78 . Because vertical duct  24  via interior passageway  58  passes warmed air over an interior surface  52  of windshield  18 , by conduction, heat passes through a thickness of windshield  18  to an exterior surface  76  of windshield  18  and melts any accumulated snow and ice  78  that may exist and may prevent any future accumulation of snow and ice. 
         [0022]    With reference to  FIG. 5 , air  46  may be delivered into horizontal duct  26 , which may be located against windshield  18  such that seals  64  are adhered to an interior surface  52  of windshield  18 . An interior wall  66 , an exterior wall  68 , and interior surface of windshield  18  may form air passageways within horizontal duct  26 . More specifically, interior wall  66  may be formed with flanges to adhere to seal  64  and define an interior air passageway  70  between interior wall  66  and interior surface  52  of windshield  18 . Exterior wall  68  may be formed with flanges to adhere to flanges of interior wall  66  such that an exterior air passageway  72  is formed between interior wall  66  and exterior wall  68 . Thus, horizontal duct  26 , in conjunction with interior surface  52  of windshield  18 , defines two flow paths to direct air relative to HVAC case  30 . More specifically, air passageway  70  is defined between interior surface  52  of windshield  18  and interior wall  66  and is an interior passageway of horizontal duct  24  that receives warmed air from HVAC case  30  from air conditioned by evaporator  32  and warmed by heater core  34 . Upon air  46  passing through air passageway  70  against interior surface  52  of windshield  18 , air reaches an end  74  of interior wall  66  of horizontal duct  26  and flows around end  74  and into air passage  72 . Like duct  24 , a chamber may be formed beside end  74 , at an end of duct  26 , such that air is turned or directed 180 degrees in the opposite direction as air in air passageway  70 . Thus, air in air passageway  70  and air passageway  72  flows in opposite directions and air  46  within air passageway  72  is returned to return air duct  48  so that air  46  may be delivered into HVAC case  30 , where it may again be conditioned. 
         [0023]      FIG. 7  depicts an enlarged view of manifold  80 , which as depicted in  FIG. 1 , facilitates a juncture of vertical duct  24  and horizontal duct  26 . Manifold  80  may be an air distributing and blending device that may receive air  46  from feeder duct  44  connected to HVAC case  30 . More specifically, an inlet  88  at an HVAC branch  82  of manifold  80  may receive air  46  from feeder duct  44 . Upon air  46  being received at branch  82 , air  46  may subsequently be divided such that a portion flows to each of vertical branch  84  and horizontal branch  86 . Thus, air  46  is depicted as exiting vertical branch  84  at an outlet  90  en route to vertical duct  24  and exiting horizontal branch  86  at an outlet  92  en route to horizontal duct  26 . Because manifold  80  is a dual direction flow device, manifold  80  may receive air  46  returned from vertical duct  24  at a vertical branch inlet  94  and may receive air  46  at a horizontal branch inlet  96 . Air  46  received at inlets  94 ,  96  is blended together and then exits manifold  80  at a manifold outlet  98 , which fluidly connects to return air duct  48 . An internal manifold wall  100  separates airflow directions within manifold  80 . That is, internal manifold wall  100  separates air flowing to each of vertical and horizontal ducts  24 ,  26  from air flowing from each of vertical and horizontal ducts  24 ,  26 . Manifold  80  may be a molded, one piece part and connect to vertical duct  24 , horizontal duct  26 , feeder duct  44  and return air duct  48  by any method known by one skilled in the art, such as by clamping, gluing, press fit, etc. 
         [0024]    The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention. 
         [0025]    When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
         [0026]    Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
         [0027]    Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Moreover, the terms “vertical,” “horizontal,” “approximately vertical,” and “approximately horizontal” are meant to convey locations or positions relative to a surface of the Earth. Still yet, terms indicating “degrees” with regard to airflow, such as “180 degrees” may be other angular directions, depending upon the direction of airflow actually required.