Abstract:
A diverter for vehicle exhaust fumes inhibits or prevents the accumulation of exhaust fumes in a trailer towed by a vehicle. The diverter includes a flexible component ( 67 ) which is able to accommodate misalignment between the vehicle and trailer during transport. A coupling ( 64, 65 ) is used to removably attach the diverter to a vehicle exhaust ( 62 ).

Description:
BACKGROUND OF THE INVENTION 
   1. Technical Field 
   The present invention relates to exhaust components and more particularly to a diverter which is used in conjunction with a trailer or float. 
   2. Background Art 
   A motor vehicle typically includes a rear-mounted exhaust pipe. If the vehicle is designed and sealed correctly and the exhaust pipe is properly located, it is expected that exhaust fumes will not enter the passenger compartment when the vehicle is in motion. However, some vehicles have faulty sealing or suffer from faulty exhaust systems. Furthermore, when towing a trailer, float or other vehicle, the wake or pattern of air flow behind the vehicle and in front of the trailer, float or other vehicle may become distorted. This may cause exhaust fumes to enter the passenger compartment, for example from the trunk or boot or station wagon door. Further, it is believed that noxious exhaust fumes are drawn into a trailer, horse float or other trailer-type vehicle when it is being towed. Thus, when a vehicle such as a trailer or float is being towed, noxious fumes from the towing vehicle may enter the trailer or float when it is in motion. 
   For the purposes of the present disclosure, enclosed trailers, horse floats and a broad range of enclosed trailer structures such as those which are used as temporary or permanent residences or shelters for humans or animals are all deemed “trailers”. The purpose of the present invention is to provide an exhaust fume diverter which reduces or eliminates the flow of noxious exhaust fumes into the interior of a trailer, particularly when it is being towed. 
   SUMMARY OF THE INVENTION 
   Accordingly, the invention provides an extension conduit which extends from a forward coupling which is adapted to attach and seal the conduit to an exhaust of a towing vehicle. The conduit extends from the towing vehicle&#39;s exhaust to a location on or under a trailer. The conduit comprises a flexible portion. 
   In one embodiment of the invention, the conduit further comprises a rear coupling and a chimney. The rear coupling may be adapted to engage and seal against a lower extremity of the chimney. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings in which: 
       FIG. 1  is a schematic side elevation of a towing vehicle and a trailer; 
       FIG. 2  is a side elevation of a towing vehicle and trailer equipped with an exhaust fume diverter shown in  FIG. 2 ; 
       FIG. 3  is a top plan view of a trailer hitch frame within which is concealed a section of the conduit of the exhaust fume diverter shown in  FIG. 2 ; 
       FIG. 4  is a schematic side elevation of a towing vehicle and trailer incorporating an exhaust diverter according to a second embodiment of the present invention; 
       FIG. 5  is a perspective side elevation of a vehicle and trailer incorporating a further example of an exhaust fume diverter of the present invention; 
       FIG. 6  is a plan view of an exhaust fume diverter of the present invention; 
       FIG. 7  is a perspective side elevation of a vehicle and trailer incorporating another example of the exhaust fume diverter of the present invention; 
       FIG. 8  is a partially cross-sectioned side elevation of a bend and exhaust adapter which may be used in the exhaust fume diverter of the present invention; and 
       FIG. 9  is a side elevation of a bayonet coupling used in an example of the exhaust fume diverter of the present invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As shown in  FIG. 1 , a towing vehicle  10  which is pulling or towing a trailer, float or other type of trailer  11  creates a wake zone  12 . Within the wake zone  12 , air is accelerated and in part turbulated by the movement of the vehicle and trailer  10 ,  11 . Air  13  which is out of the wake zone  12  is not affected by the movements of the vehicle  10  or trailer  11 . In a towing vehicle  10  with a conventional exhaust pipe  14 , noxious fumes  15  from the vehicle&#39;s exhaust  14  are likely to enter the interior of the trailer  11 . In some cases, turbulent patterns are created in the space  16  located between the vehicle  10  and the trailer  11 , which patterns cause exhaust fumes to enter the passenger compartment of the vehicle  10 . The intrusion of exhaust fumes into the passenger compartment of the vehicle  10  has obvious negative consequences. 
   It should also be noted that where the trailer  11  is carrying live animals such as in the case of a horse float, the entry of exhaust fumes into the interior can have serious consequences to the health or sporting performance of any animal contained within the trailer or float  11 . 
   Noxious exhaust fumes can also accumulate within an empty trailer  11  and remain within it after the trailer is parked, so that humans that enter the trailer  11  even after it is parked are exposed to accumulated exhaust fumes. Vehicle exhaust gases are rich in carbon monoxide, which is an odorless, colorless toxic gas which is heavier than air. For this reason, the occupants of the trailer  11 , whether human or animal, may not be aware of the presence of exhaust fumes which have entered or accumulated within the interior compartment of the trailer  11 . 
   As shown in  FIG. 2 , an exhaust fume diverter  20  comprises a conduit  21  which extends from the vehicle exhaust pipe  14  to the lowermost extent  22  of an exhaust riser or chimney  23 . A coupling  24  is used to join and seal the conduit  21  to the exhaust pipe  14 . The coupling  24  may be flexible enough to seal against the exhaust pipe  14  or may be equipped with straps or buckles to positively seal the conduit  21  against the exhaust pipe  14 . The conduit  21  may comprise a flexible hose, a rigid pipe or any combination of these. In the example depicted in  FIG. 2 , the riser or chimney  23  is a rigid tube or pipe which is attached to the conduit  21  by a coupling  25 . In preferred embodiments of the invention, the distal end  26  of the riser or chimney  23  is high enough above the highest point  27  of the trailer  11  so as to vent the exhaust fumes  28  above and out of the wake zone  12 . In this example, the chimney or riser  23  is shown as being located at the rear of the trailer  11 . It will be appreciated that the riser or chimney  23  could be mounted toward a forward portion  29  of the trailer if it were high enough to minimize the risk that exhaust fumes  28  could be introduced into the interior compartment of the trailer  11 . 
   In many instances, some or all of the frame or chassis of the trailer vehicle  11  are fabricated from tubular or hollow steel components. As shown in  FIG. 3 , portions of the conduit  21  may be concealed within hollow chassis elements. In this example, the conduit  21  enters a forward portion  30  of the trailer hitch  31 . The conduit  21  then passes through the hollow frame to a convenient exit point. 
     FIG. 4  illustrates an embodiment wherein the conduit  21  leads from the exhaust coupling  24  to a riser coupling  41  which is located adjacent a forward portion  42  of the trailer  11 . Accordingly, the riser or chimney  43  is mounted adjacent the front portion  42  and rises to a point above the wake zone  12 . 
   As shown in  FIG. 5 , a further embodiment demonstrates that the conduit  21  can extend from the exhaust  14  and the exhaust coupling  24  to a point below the chassis of the trailer  11  and terminating at the rear of the trailer  11  at a position which would correspond to the location of a conventional exhaust discharge in a motorized vehicle. In some cases, the terminal portion  50  of the conduit  21  may be turned downward so as to encourage the exhaust fumes to either exit the wake zone  12  or at least prevent them from entering the interior compartment of the trailer  11 , once such fumes are discharged from the diverter. 
   It will be appreciated that the conduit  21  may be fabricated from flexible hose or from rigid elements such as steel tubes. Where flexible hose is used, for example, at the forward portion of the conduit where it couples with the vehicle&#39;s exhaust  14 , such flexible hose must be selected so as to withstand the heat and pressure generated by the vehicle&#39;s exhaust. 
   An example of such a system is disclosed with reference to  FIGS. 6 and 7 . As shown there, a diverter  60  comprises an (optional) exhaust adapter  61  which attaches to a vehicle exhaust pipe  62 . Attachment may be by welding or by a set screw or other clamping apparatus  63 . In the alternative, the flexible component or the bend  66  may be coupled directly to the vehicle exhaust. 
   The flexible component may assume various forms. In simple embodiments, a heat-resistant polymer may be used to construct a flexible hose or tube. An all-polymer construction, reinforced or otherwise, is easy to couple and inexpensive but not as durable as other flexible component options. Another flexible component is depicted in  FIGS. 6 and 7 . This embodiment uses a flexible metal spring or coil outer piece  67   a  to contain and protect an inner tube  67   b . The inner flexible tube  67   b  may be fabricated from one or more layers of woven heat-resistant textile fabrics. In preferred embodiments, the inner layers are more resistant to heat than the outer layers. In this way a gas-tight, strong, heat-resistant and flexible structure is formed for carrying exhaust gases away from the vehicle exhaust. Unlike other flexible heat-resistant tubes, this type of structure is highly flexible, offers little resistance to flexing, has a small bend radius and may be flexed repeatedly without failure. 
   The adapter  61  is sized to fit a particular exhaust pipe size and present a coupling half  64  to a cooperating coupling half  65  which is carried by a rigid exhaust bend  66 . In this example the bend is a ninety degree bend. The bend changes the direction of flow of the exhaust gases toward the towing ball. The exhaust gases are carried in this direction by a flexible component  67  which is coupled to the bend  66  with a suitable fixture  68  or coupling. This allows a central section  69  of the flexible component  67  to be positioned adjacent to the tow ball. In this way the flexible component  67  flexes with minimum stretching as the vehicle turns and negotiates bumps and the angle between the vehicle and trailer changes. The distal end  70  of the flexible section  67  couples or is otherwise affixed to a rigid section of exhaust pipe  71  which extends from the flexible section termination point to preferably a location under the trailer. The rigid section  71  is therefore exposed. To protect the safety of humans and animals in the vicinity, a protective heat shield  72  is located over the exposed section  71  of pipe. The heat shield  72  is, for example, a perforated metal half tube or “U”-shaped structure (in cross-section) which includes tabs  73  or other means for attaching the shield  71  to the trailer structure. The exposed section then continues by way of a rigid section  74 , under the trailer in this example, to a location  75  just forward of the front trailer wheels  76 . The rigid section  74  may incorporate whatever bends  76  and brackets  77  as are required to suit a particular trailer. 
   As shown in  FIG. 8 , coupling between any rigid or flexible components of the present invention may be achieved by providing flanges  81 ,  82  on adjacent components and a clamp  83  having a “U”-shaped cross-section around the adjacent flanges  81 ,  82 . In this example the coupling is made between the exhaust adapter  61  and the bend  66 .  FIG. 8  also shows the use of cooling fins on the bend  66 , particularly near the hottest portion of the bend where the exhaust fumes impact on the turning portion of the bend wall. 
   As shown in  FIG. 9 , a bayonet coupling with two halves  90 ,  91  may also be used. As is known in the coupling art, the female half  91  receives the male half with an optional rotating action which seals the halves together. Locking arms are pivotable to interlock the halves. This type of coupling is particularly useful in joining the flexible portion  67  to the bend  66  or the bend  66  to the exhaust adapter  61 . In some embodiments, the halves do not rotate and in fact are prevented from rotating by an anti-rotation pin  92  on the inner male and a cooperating slot  93  on the inner wall  94  of the female half  91 . This prevents the coupling from rotating during use. In preferred embodiments the male is fitted to the vehicle exhaust, for example, with set screws  95 . Also preferred is that a single locking lever is used (two are shown). The single lever  96  should point down toward the ground in use, for ease of assembly. An opening  97  in the retention ear  98  is provided for receiving a safety anti-release pin or chain. 
   It will also be appreciated that one purpose of the exhaust fume diverter of the present invention is to minimize the risk of noxious exhaust fumes entering the interior compartment of a towed trailer, float or other vehicle. To do this, the exhaust fumes must exit the diverter at a point which minimizes this risk of entry. In some examples (for example  FIG. 5 ) the exhaust exit is toward, adjacent to or beyond the rearmost portion of the towed vehicle  11 . This corresponds to a generally conventional exhaust discharge point in the sense that it is where the exhaust discharge would be located if the trailer  11  were a powered vehicle. In other embodiments (for example  FIGS. 2 and 4 ) the exhaust fume diverter incorporates a riser or chimney which allows the discharge point of the diverter to be above the uppermost point of the trailer  11 . It is desirable but not essential that the discharge point be near to or above the uppermost point of the trailer  11 . In particularly preferred embodiments, the riser or chimney extends above the point which constitutes the boundary of the wake zone  12 . 
   It will also be appreciated that the exhaust fume diverter of the present invention may be provided as an after-market kit which may be installed on practically any towed vehicle. However, it is equally desirable that the exhaust fume diverter be installed by the manufacturer of a trailer  11  so that the trailer  11  is purchased with the exhaust fume diverter installed and ready for coupling to the exhaust of the vehicle which tows it. When provided on or for a particular vehicle, it may have fewer points of coupling of components and may not necessarily require an exhaust adapter. 
   Although the present invention has been disclosed with reference to particular materials and details of construction, these should be understood as having been provided by way of example and not as limitations to the scope or spirit of the invention.