Abstract:
A tractor-trailer wind fairing panel assembly includes two side and one top fairing panels that mount to a truck tractor and aerodynamically bridge the air gap to any fifth-wheel utility trailer being pulled by the tractor. Such fairing panels are hinged on their leading edges so their distal trailing edges can swing a bit to accommodate twisting and turning of the utility trailer during use. The hinges all mount to a cab adapter collar that helps fit the whole to the contoured surfaces of the rear of a typical truck tractor cab. The distal ends of the trailing edges are fitted with inward directed wind seals. Rows of ball bearing pucks are arranged in the crowns of the inward directed wind seals to reduce friction and wear as the fairing panels swing to accommodate the twisting and turning of the utility trailer.

Description:
1. FIELD OF THE INVENTION 
     The present invention relates to methods and devices to improve the operating fuel economy of tractor-trailers operated on highways, and more specifically to practical and lightweight wind fairing panels that aerodynamically eliminate turbulence and air drag by bridging the gaps between the rear of tractor cabins and the noses of the trailers the tractors pull. 
     2. DESCRIPTION OF THE PRIOR ART 
     It is generally understood that tractor-trailer combinations create a lot of wind turbulence and air drag as they move at speed down highways across American highways. Natural Resources Canada (NRC) estimated in 2010 that given 100% of fuel energy, 50% is lost in heat rejection and exhaust heat. Of the 50% left, 42% is lost in braking power, 22.3% in aerodynamic drag, 13.4% in rolling resistance, etc. So the elimination or reduction in aerodynamic drag can result in substantial savings of fuel energy. 
     Aerodynamic drag cannot be eliminated entirely, but significant fuel savings can be obtained by the careful placement of chassis skirts, side extenders, roof fairing panels, wheel covers, and spoilers about both the tractor and trailer and the coupling area between them. 
     A typical commercial truck-tractor in the United States is usually driven about 12,000 miles a month on average. Any less than that its operation will not be profitable. The average fuel economy for semi-trucks is about six miles-per-gallon. On average, such trucks consume 2,000 gallons of diesel fuel each month. The cost of diesel has been very high lately. The amount of fuel consumed by the entire trucking industry is staggering. By one estimate, there are fifteen million trucks travelling on American highways. 
     A change is needed in making our use of fuel more efficient. 
     One day watching how a truck with a manufacturer-installed gap spoiler was doing at parking up to a loading dock, the driver made too sharp a turn and busted the spoiler. Closing the tractor-trailer gap completely seemed to be a superior idea, if it could be accomplished. Aerodynamically it would make a tractor and its trailer one continuous whole. The secondary air pressure on the front of the trailer could be reduced or nearly eliminated. 
     Reducing the trailer&#39;s wind resistance will reduce the amount of energy required to run at highway speeds. The amount of fuel consumed would be less, significantly less. Lower expenses on fuel would indirectly benefit the Economy and everyone of us. Moreover, using less fuel helps to better preserve our Environment because fewer pollutants and other particles are released into the atmosphere. 
     SUMMARY OF THE INVENTION 
     Briefly, a tractor-trailer wind fairing panel assembly embodiment of the present invention comprises two side and one top fairing panels that independently mount to a truck tractor and bridge the air gap to any fifth-wheel utility trailer being pulled by the tractor. Such fairing panels are each hinged on their leading edges so their distal trailing edges can swing a bit to accommodate the twisting and turning of utility trailers during use. The hinges all join to a cab adapter collar that helps fit the whole to the contoured surfaces of the rear of a typical truck tractor cab. The distal ends of the trailing edges are fitted with inward directed wind seals. Rows of ball bearing pucks are arranged on the crowns of the inward directed wind seals to reduce friction and wear as the fairing panels slide on the trailer sides to accommodate the twisting and turning of the utility trailer. 
     These and other objects and advantages of the present invention no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments which are illustrated in the various drawing figures. 
    
    
     
       IN THE DRAWINGS 
         FIG. 1  is an exploded assembly view in above-right-rear perspective of a tractor-trailer wind fairing panel assembly embodiment of the present invention; 
         FIGS. 2A-2E  provide further detailed views of the pieces of the tractor-trailer wind fairing panel assembly of  FIG. 1 ; 
         FIG. 2A  shows the tractor-trailer wind fairing panel assembly as assembled from above-left-rear perspective; 
         FIG. 2B  shows the tractor-trailer wind fairing panel assembly from the rear as viewed from a utility trailer attached to the truck-tractor; 
         FIG. 2C  shows the tractor-trailer wind fairing panel assembly from the top with the truck-tractor facing left in the drawing; 
         FIG. 2D  is a drawing showing the left side of a left facing tractor-cab and cab adapter collar of the tractor-trailer wind fairing panel assembly of  FIG. 1 . And further shows an exploded view of the right side fairing panel seen from its left, and an end view of the outer part and corner cover, and an exploded bottom view of the two parts of the right side fairing panel; 
         FIG. 2E  is a drawing of an assembled wind fairing panel assembly of  FIG. 1  as seen from the left side of a left facing tractor-cab; 
         FIG. 3  is an exploded assembly view drawing of an alternative construction for a side fairing panel with the corner cover integrated into the outer skin. Two rows of ball bearing pucks are disposed in a wind seal channel that is covered by an access plate; 
         FIG. 4  is a perspective view diagram of a spring bracket used to mount the assembly of  FIG. 1  to the tractor can and that controls the side panel swings. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  represents a tractor-trailer wind fairing panel assembly  100  that aerodynamically bridges the air gap between the rear cab of a truck-tractor  102  and the front flat nose of its fifth-wheel type trailer. The object of which is to make the tractor-trailer combination more aerodynamic, reduce air drag, and yield fuel savings at highway speeds. 
     The tractor-trailer wind fairing panel assembly  100  comprises a cab adapter collar  104  having vertical left and right side lengths  105 ,  106  and an inter-connecting horizontal top length  107 . Such cab adapter collar  104  is typically one hundred seventeen inches tall, ninety three inches wide, and at least six inches thick. The cab adapter collar  104  is contoured on its front face  108  in a way that matches the contours of a rear outer periphery of a drivers cab of a particular type of truck-tractor  102 . A set of left, top, and right continuous hinges  110 - 112  are correspondingly disposed vertically in each of a rear face of each the left and right side lengths  105 ,  106 , and horizontally in a rear face of the inter-connecting top length  107 . 
     A left fairing panel  114  is vertically hinged to the left length  105  of the adapter collar  104  at its rear face, and is supported by the corresponding continuous hinge  110 . A distal vertical edge with a wind seal  116  is free to swing left-right within a limited range. For example, to accommodate a typical fifth-wheel type trailer one hundred and eight inches wide. During use, such distal vertical edge at wind seal  116  is kept closed up against the front nose of the fifth-wheel type trailer by a heavy spring, e.g., in continuous hinge  110 . Such wind seal  116  slides fore-and-aft as the tractor-trailer combination makes left and right turns. The left fairing panel  114  has at its top edge an inwardly curled lip, e.g., a corner cover  118  to wind seal that corner edge with the adjacent edge of a top fairing panel  120 . 
     Conventional fifth-wheel type utility trailers are usually wider abeam and taller than the rear of popular types of truck-tractor cabs  102 . So, in normal operation the three fairing panels of tractor-trailer wind fairing panel assembly  100  on the whole will be flared out a bit toward the trailer. For example, flaring in width from 94″ to 108″. 
     The top fairing panel  120  has a straight rectangle shape, not trapezoid. Such is needed in order for the top fairing panel  120  to be able to fold completely down between hinges  110  and  112  during storage. The leading edge of top fairing panel  120  is attached by top hinge  111  to the horizontal rear face of the inter-connecting top length  107 . A distal horizontal edge is kept closed down to form a wind seal  122  down against the top of the front nose of the fifth-wheel type trailer. Such wind seal  122  twists, rotates, and slides around as the tractor-trailer combination makes left and right turns and goes up and down bumps and dips in the road. 
     A pair of gas charged piston lifts allow the user to position top fairing panel  120  at various elevations. See  FIG. 2B . For example, to enable positioning of the top fairing panel  120  and wind seal  122  to just clear the top edge of the front nose of the fifth-wheel type trailer during its coupling to the truck-tractor. 
     A right fairing panel  130  is vertically hinged to the right length  106  of the adapter collar  104  at its rear face, and is attached by corresponding continuous hinge  112 . A distal vertical edge with a wind seal  132  is free to swing left-right within a limited range. During use, such distal vertical edge  132  is kept closed up against the front nose of the fifth-wheel type trailer by a heavy spring, e.g., incorporated within continuous hinge  112 . This wind seal  132  too twists, and slides fore and aft as the tractor-trailer combination makes left and right turns and maneuvers the road. The right fairing panel  130  has at its top edge an inwardly curled lip  134  to seal out wind at that corner edge with the adjacent edge of top fairing panel  120 . 
     Nothing of tractor-trailer wind fairing panel assembly  100  needs to be mounted to the utility trailer. This is an advantage because utility trailers belonging to large hiring companies can be freely mixed and matched to the truck-tractors of independent owner-operators. The aerodynamic fuel savings stay with the truck-tractors of their independent owner-operators. 
     Set of brackets and springs are conventionally arranged to press the distal edges of the left, right, and top fairing panels against any trailer coupled to the particular type of truck-tractor. Here, these are further arranged to limit the inward swings of each of the left, right, and top fairing panels to no less that that needed for any trailer coupled to the particular type of truck-tractor to press itself in between the distal ends while coupling. 
       FIG. 2A  shows an assembled tractor-trailer wind fairing panel assembly  100  mounted to the backside of a tractor-cab  102 . 
     The top fairing panel  120  represents a special case in that it must be held aloft high enough during tractor coupling to the trailer that the top fairing panel&#39;s horizontal distal edge can ride up over the top of the nose of the trailer without interference or damage. The top fairing panel  120  must also be able to fold down flat enough against the rear of the tractor cab such that the two side fairing panels can be folded over it for secure storage. 
       FIG. 2B  alone shows how two gas lift support struts  201  and  202  are attached to the bottom outside pivot points of a top hinge support and bracing bracket  203 . Bracket  203  bolts to the tractor-cab  102  at the center and provides a shelf to support the forward fixed part of top hinge  111  and the whole of cab adapter  104 . The two gas lift support struts  201  and  202  are very similar to those used to support opening and closing tailgates and hoods in common SUV&#39;s, only heavier duty, and attach up under top fairing panel  120 . They completely counter-balance the weight of top fairing panel  120  and make it easy for a user to raise and lower top fairing panel  120 . 
     A very important consideration in such construction is that the whole, and especially the fairing panels must be lightweight and yet stiff enough not to rattle and buffet in highway winds. The top and side fairing panels are therefore preferably two-ply, hollow and formed of two acrylonitrile butadiene styrene (ABS) plastic sheets  210  and  211  (as shown only in  FIG. 2D ). The inner sheets  210  have several stiffening ribs  212  that control panel twisting, flexing, and bowing. For example, these ribs  212  can be vacuum-formed. Other contours and shapes can also be employed to impart stiffness and strength. 
       FIG. 3  represents an alternative construction of a side fairing panel  300 . An outer skin  302  is notched to receive a ball bearing galley access panel  304 . The outer skin  302  incorporates a rollover in a curved section  306 . Here, a separate corner cover  118 ,  134  is not used, it is integrated. A slightly shorter length inner skin  308  is welded, fastened, or otherwise joined to the outer skin  302  all along its outer periphery. A set of several reinforcing ribs  310  are disposed parallel to one another within inner skin  308 . 
     A ball-bearing channel  312  forms a dished gallery of ball bearing pucks  314 . These are set into two parallel rows of bearings  316  and  318 . A single large ball bearing exposed in the center of each ball bearing puck  314  faces toward a line of contact where the side fairing panel  300  forms a sliding wind seal with a utility trailer. These ball bearing pucks  314  can comprise all plastic materials, such as nylon which has good wear resistance. 
     Referring now to  FIG. 4 , at least four brackets  400  are used to mount assembly  100  securely to cab  102  by the custom cab adapter  104 , e.g., two at both sides. Each model of truck will require a customized bracket to insure the best fitment. When two such brackets  400  are used on each side, each includes a heavy piece of curved spring steel  402  captured behind a pair of removable locking pins  404  and  406 . The springs  402  counteract any unwanted folding of the side fairing panels too far in and/or out while in use. But the configuration shown here still allows a user to open a side panel to access the fifth wheel coupling, air hoses, and electrical cables. Removal of such locking pins  404  and  406  lets the assembly  100  to be folded-up for storage. The brackets  400  may also use extension pieces and blocks to cover wider gaps between the truck cab and the fairing panels. 
     Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that the disclosure is not to be interpreted as limiting. Various alterations and modifications no doubt become apparent to those skilled in the art after having read the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the “true” spirit and scope of the invention.