Patent Abstract:
An exhaust module made of a thermoplastic material which is connected to a fascia or bumper of a vehicle. In one embodiment, the hybrid fascia mounted exhaust tip assembly includes a bracket. The bracket has a large diameter portion which surrounds, but is not in contact with, an exhaust pipe. The exhaust pipe is free to move around as a result of the vehicle traveling over bumps in the road and around turns. The bracket also has a small diameter portion which is connected to the large diameter portion. A ring tip has a portion that slides onto a bezel portion of the small diameter portion.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/574,251, filed Jul. 29, 2011 and U.S. Provisional Application No. 61/574,330, filed Aug. 1, 2011. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to hybrid fascia mounted exhaust module made primarily of thermoplastic material resistant to corrosion, which requires minimal secondary operations during assembly. 
     BACKGROUND OF THE INVENTION 
     Exhaust systems are used for just about every type of vehicle currently in production around the world. It is commonplace for vehicle owners to add accessories to the vehicle to change the appearance of the vehicle. Once particular type of accessory is a decorative exhaust tip typically made of steel or another type of metal which is chrome plated to provide for an aesthetically pleasing appearance. 
     One type of design uses a slip-on type steel exhaust tip that is connected directly to the end of the exhaust pipe. This design is subject to corrosion and requires additional welding during assembly operations. 
       FIGS. 1-2  depict a prior art design that has a metal exhaust module  100  that attaches to the rear bumper fascia  102  of the vehicle. The exhaust module  100  has metal body  104  and welded mounting flanges  106 . The welded flanges  106  are used to connect the metal body  104  a larger spacer bracket  108  that connects to the rear fascia  102 . The connection of the welded flanges  106 , spacer  108  and rear fascia  102  is made with several bolts  110  and nuts  112 . An outer surface  114  of the metal body  104  is often chrome polished or painted and can be seen when a person looks at the rear bumper fascia  102  of the vehicle. The exhaust module  100  is not connected to the exhaust pipe but has an inlet portion  103  that is positioned in close relation to the end of the exhaust gas tailpipe for receiving and passing exhaust gas through the exhaust module. Exhaust modules of this type often are formed of several welded steel parts and brackets that come into direct contact with the exhaust gas from the exhaust pipe being formed of steel or some other types of metal. 
     The above described designs result in undesirable gap between the chrome tip of the exhaust tip or exhaust module and the rear bumper fascia of the vehicle because the design must account for thermal expansion of the metal portions exposed to the hot gasses from the exhaust pipe. The exhaust modules designs that mount to the rear fascia also add a considerable amount of weight causing undue stress on the rear fascia, which is often made of plastic. Also both the metal slip on exhaust tip and exhaust module designs described above are costly to produce because they are primarily made of metal. It is therefore desirable to design an exhaust module that is light weight, low cost, and aesthetically pleasing by having a tight fit or minimal gap to the rear fascia of the vehicle. It is also desirable to produce an exhaust gas module that has a minimal number of components for ease of assembly, which would also result in cost savings. 
     SUMMARY OF THE INVENTION 
     The present invention is an exhaust module made of a thermoplastic material which is connected to a fascia or bumper of a vehicle. In one embodiment, the hybrid fascia mounted exhaust tip assembly includes a bracket. The bracket has a large diameter portion which surrounds, but is not in contact with, an exhaust pipe. The exhaust pipe is free to move around as a result of the vehicle traveling over bumps in the road and around turns. The bracket also has a small diameter portion which is connected to the large diameter portion. A ring tip has a portion that slides onto a bezel portion of the small diameter portion. The connection between the ring tip and the small diameter portion provides for a reduced clearance between the ring tip and the fascia, helping to provide for an aesthetically pleasing appearance. In one embodiment, the ring tip is chrome plated. In other embodiments, the ring tip may be made of bright stainless steel, and stamped into the correct shape. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a prior art exhaust gas module and fascia; 
         FIG. 2  is a side plan view of a mounted prior art exhaust gas module to a rear fascia of a vehicle; 
         FIG. 2A  is an exploded perspective view of an exhaust gas module in accordance with one embodiment of the present invention; 
         FIG. 2B  is a perspective view of an assembled exhaust gas module in accordance with one embodiment of the present invention; 
         FIG. 3A  is a schematic side view diagram of a prior art exhaust tip connected to an exhaust pipe and positioned relative to a portion of a partially broken away portion of the rear fascia; 
         FIG. 3B  is a side schematic view of an exhaust module relative to the rear fascia and exhaust pipe in accordance to one embodiment of the present invention; 
         FIG. 4A  is a perspective view of an alternate embodiment of a ring tip assembly in accordance with one embodiment of the present invention; 
         FIG. 4B  is an exploded perspective view of an alternate embodiment of the bracket assembly and ring tip assembly of the exhaust gas module in accordance with the present invention; 
         FIG. 4C  is a perspective view of the assembled exhaust gas module of  FIG. 4B ; 
         FIG. 5  is a cross-sectional plan view of the exhaust gas module assembled to the bracket taken along section line  5  in  FIG. 2B ; 
         FIG. 6  is an exploded perspective view of an alternate embodiment of the exhaust module assembly wherein the bracket is integrated into the rear fascia; 
         FIG. 7A  is a cross-sectional side schematic view of a mold machine for an alternate embodiment of the present invention where the ring tip is insert molded to the bracket; 
         FIG. 7B  is a cross-sectional side schematic view of a mold machine for an alternate embodiment of the present invention where the ring tip is insert molded to the bracket; and 
         FIG. 7C  is a cross-sectional side view of an alternate embodiment of the exhaust module wherein the ring tip has been insert molded onto the bracket. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Referring to the  FIGS. 2A ,  2 B,  4 A,  4 B,  4 C,  5 ,  6  and  7 C, which are the figures of the embodiments of the present invention generally, an exhaust module according to the present invention is shown generally at  10 . The module  10  includes a bracket, shown generally at  12 , and a ring tip, shown generally at  14 . The bracket  12  has a plurality of mounting flanges  16 , which are used for connecting the bracket  12  to the fascia or bumper of a vehicle (not shown). 
     The bracket  12  includes a large diameter portion  18  and a small diameter portion  20 . The large diameter portion  18  surrounds the end portion of an exhaust pipe  22 , which is connected to a muffler, or other exhaust system component. The large diameter portion  18  is about four inches in diameter, and the exhaust pipe  22  is about two inches in diameter, which creates about a one-inch clearance between the exhaust pipe  22  and the large diameter portion  18  of the bracket  12 . This clearance limits the exposure of the bracket  12  to the temperatures of the exhaust pipe  22 , and allows for the exhaust pipe  22  to have some movement, or “play,” as the vehicle travels over bumps, around curves, and the like. While a diameter of four inches for the large diameter portion and a diameter of two inches for the exhaust pipe is disclosed, it is within the scope of this invention for different diameters to be used depending upon the size of the diametrical size of the exhaust pipe. 
     The bracket  12  in one embodiment of the invention is formed entirely of plastic or polymer such as glass filled nylon, ABS or other polymer materials such as thermoplastic olefins. Forming the bracket  12  out of entirely polymer material is a significant advantage over the prior art which is typically formed of some type of metal, such as steel. Therefore, it is within the scope of this invention for the bracket  12  and to not be formed of metal. It is also within the scope of this invention for the bracket  12  including the large diameter portion  18 , small diameter potion  20  to not be formed of metal. It is further within the scope of this invention for the bracket  12 , including the large diameter portion  18 , small diameter portion  20  and mounting flanges  16  to not be formed of metal. It is also within the scope of this invention for the bracket  12 , including the large diameter portion  18 , small diameter portion  20 , mounting flanges  16  and ring tip  14  to not be formed of metal. 
     The connection between the ring tip  14  and bracket  12  can vary depending on the particular embodiment of the invention. Referring to  FIGS. 2A ,  2 B and  5  the ring tip  14  is connected to the bracket  12  by snap fit tabs. The ring tip  14  has resilient tabs  34  having apertures  36  that connect with protrusions  38  formed on the bracket  12 . In another embodiment of the invention shown in  FIGS. 4A and 4B  the ring tip  14  is slid over the small diameter portion  20  until the mounting features  26  of the small diameter portion  20  becomes interlocked with the mounting features  28  formed integrally with a sleeve  30  of the ring tip  14 . In this particular embodiment the mounting features  26 ,  28  are a “toy tab” or tongue in groove feature. In other embodiments, the ring tip  14  and bracket  12  are connected through other processes, such as adhesion, vibration welding, or the like. 
     In the embodiments of the invention described herein the bracket  12  has a small diameter portion  20 . The small diameter portion  20  is connected to the large diameter portion  18  through a tapered portion or bezel portion  24 . The sleeve  30  of the ring tip  14  terminates at a groove  32  portion of the ring tip that receives at least part of the small diameter portion  20  when the module  10  is assembled together. When assembled the bezel portion of the small diameter portion  20  rests against and supports the ring tip  14 . This allows the ring tip  14  to be made thinner, which cuts cost and weight. The ring tip  14  in one embodiment is formed of thin gauge stainless steel that is less than fifty thousandths of an inch thick. In another embodiment of the invention the ring tip  14  is formed of thin gauge stainless steel that is between twenty thousandths to forty thousandths of an inch thick. In another embodiment of the invention the ring tip  14  is formed of thin gauge stainless steel that is between twenty thousandths and thirty thousandths of an inch thick. The thickness of the ring tip  14  can vary depending upon the environmental factors, including exhaust gas temperatures exposure for a particular application. It is also possible for the ring tip  14  to be formed of polymeric material and would include a chrome plated plastic that is accomplished using a Polychlorinated Biphenyls PCBs resin or ABS resin with subsequent chrome plating of the resin material. 
     An alternate method of assembling the ring tip  14  to the bracket  12  is shown in  FIGS. 7A-7C  wherein insert molding is used to connect the ring tip  14  to the bracket  12 . This process involves pre-forming the ring tip  14 , which has flow grooves  15  formed at opposite edges of the ring tip  14 . The ring tip  14  is placed into a mold cavity of a first platen  48  of a molding machine  46 . A second platen  50  is closed on to the first platen  48  and molten polymer  52  is flowed into the molding machine  46  to form the bracket  12 . The ring tip  14  becomes connected to the bracket  12  by molten polymer  52  material flowing into the flow grooves  15  of the ring tip  14  prior to solidifying and forming the completed bracket  12 . 
     Once the ring tip  14  is connected to the bracket  12  according to either the snap fit, toy tab, or insert molded methods of assembly described above, the ring tip  14  is brushed and polished to achieve an aesthetically acceptable part. Performing the brush and polish step once assembly is completed allows for the removal of any mold release material that can be present, particularly if the insert molding method of assembly is used. The brush polishing step also removes scratches or flash material that can be present on the ring tip  14 . 
       FIG. 6  shows another alternate embodiment of the invention wherein an exhaust module  300  is integrated into a fascia  302 . In this particular embodiment of the invention, the bracket  12  shown in the other embodiments is not present since the exhaust module  300  is molded into the rear fascia during the process of forming the rear fascia. Once the rear fascia  302  is conformed, a large diameter portion  18  and small diameter portion  20  is present and is capable of receiving the ring tip  14 . The ring tip  14  can connect to the small diameter portion  20  in the same manner as described in all the embodiments above. This particular embodiment of the invention further eliminates components by no longer requiring a bracket  12  and fasteners for connecting to the rear fascia. Additionally, prior to assembly of the ring tip  14 , the fascia  302  can be painted or completed without any special or additional steps since the ring tip  14  will be connected to the small diameter portion  20  in a subsequent step. Therefore, there is no concern about painting or treating the exhaust module  300  during the formation of the fascia  302 . 
     Referring now to  FIGS. 3A and 3B , the advantages of the present invention are over prior art as shown.  FIG. 3A  is a schematic side view of a prior art steel exhaust tip assembly  200 . A steel exhaust tip  202  is connected to the end of an exhaust tail pipe  204 , usually by welding, fasteners or some other attachment mechanism. The steel exhaust tip  202  is positioned below a rear fascia  208  at a distance that provides a suitable gap  206  between the rear fascia  208  and the steel exhaust tip  202 . The gap  206  distances can vary but is usually approximately 28 mm or enough distance to account for thermal expansion of the exhaust tip  202  and movement of the assembly  200  as the vehicle moves. 
       FIG. 3B  shows the exhaust module  10  schematically assembled to a rear fascia  40  in accordance with the present invention. A gap  44  is shown between the exhaust module  10  and rear fascia  40 . The gap  44  is less than or equal to 5 mm. Thus, the present invention is an improvement over the prior art because a more aesthetically pleasing appearance can be achieved due to the tighter fit and reduced gap  44  between the exhaust module  10  and rear fascia  40 . 
     One reason for the present invention&#39;s improvement over prior designs is that the prior designs use a large percentage of metal parts, which requires the designs to account for thermal expansion of the exhaust tip or steel exhaust module. The exhaust module  10  of the present invention is formed entirely of polymer material and in one embodiment implements a thin gauge steel ring tip  14 . A smaller gap can be achieved since the polymer material of the exhaust module  10  will not be subject to the same level of thermal expansion that the prior modules are exposed to. Thus, forming the exhaust module  10  of polymer material represents an improvement over existing exhaust modules and exhaust tip designs. 
     The bracket  12  is a glass-filled, nylon part, or is made from another type of thermoplastic material. The ring tip  14  is made from a polycarbonate (PC), acrylonitrile butadiene styrene (ABS), or other type of thermoplastic material which is injection molded. The ring tip  14  is also chrome plated, to provide an aesthetically pleasing appearance. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the essence of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Technology Classification (CPC): 5