Abstract:
Either or both of an exhaust pipe coupled to the output end of an automobile engine collector pipe or the plurality of pipes coupled to the input apertures of the collector pipe from the engine are apertured along their lengths and contained within a further surrounding pipe in providing an exhaust which simultaneously serves as a muffler for the vehicle and to traverse the various component parts of its exhaust system and/or the vehicle engine when composed of a plurality of pipe segments, individual ones of which are of preselected length, and cut at their respective ends at preselected angles for joining together in appropriate orientation.

Description:
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Research and development of this invention and Application have not been federally sponsored, and no rights are given under any Federal program. 

   CROSS-REFERENCE TO RELATED APPLICATIONS 
   NONE 
   REFERENCE TO A MICROFICHE APPENDIX 
   NOT APPLICABLE 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to internal combustion automotive vehicles, in general, and to an exhaust system which improves fuel economy, torque, and horsepower while reducing back-pressure, in particular. 
   2. Description of the Related Art 
   As is well known and understood, individual pipes are connected to the cylinder head exhausts of an internal combustion automotive engine, and coupled to the apertures of a collector pipe which in turn is coupled to the vehicle&#39;s exhaust system. As set out in my U.S. Pat. No. 5,199,258 (“Adjustable Torque/Horsepower Exhaust Control System”), header systems are available and individually tailored to a particular make and model of the vehicle to improve operating performance—but suffer the disadvantage that a header system designed for one vehicle is not interchangeable with another. As described, this follows because of the different spacings and locations of systems in the engine compartment and undercarriage of the vehicle, so that different physical and mechanical specifications have to be satisfied for each individual installation. While system performance can be improved by these header designs, their actual installation into the motor vehicle has proven quite cumbersome. In many installations, for example, the bendings in the header pipes appear to come unreasonable close to power systems for ease of installation—and, in many instances, led to a need to actually hoist the engine in order to properly place the header into position. 
   As also set out in my U.S. Pat. No. 5,144,799 (“Crossfire Calibrated Exhaust System”), the exhaust pipe which leaves the muffler in typical automotive engine constructions is most oftentimes bent in various odd-shapes so as to clear the rear housing of the automotive vehicle, the power steering systems, and other control installations, in joining up with the tailpipe to channel the exhaust flow away. Experimentation showed that these bends added such length of piping to the exhaust system as to frequently “load-up” the engine, making it difficult to breath, causing an uneven performance, choking the engine. 
   As both my patents describe, overall performance is enhanced by cutting the pipes into individual sections to clear obstructions, rather than being bent into position. Experimentation showed that this shortened the path, for example, that the exhaust gases had to take in being channeled to the outside atmosphere, and lessened any propensity for the engine “loading-up”. By selecting various diameters, lengths, and the angles at which the pipes were cut, not only were the manners of installation simplified, but a degree of calibration became available to control torque, horsepower, manifold vacuum, exhaust flow and engine temperatures associated with the various systems when in use. One of the problems which persisted, however, dealt with the “back-pressure” associated with the muffler employed, and with its overall effect on the exhibited fuel economy. 
   SUMMARY OF THE INVENTION 
   As will be seen below, the piping combination of the present invention simultaneously eliminates the conventional muffler employed in a vehicle exhaust system as a separate component, while directing the vehicle&#39;s exhaust gas flow in a manner which itself provides a “muffling” effect. As will be described, individual pipe segments are cut and angled both in the header system and in the exhaust system of the vehicle, and arranged to seat within surrounding pipes which are themselves cut and angled in individual segments in containing either or both of the exhaust pipe segments and all of the header pipe segments. With both of the exhaust pipe segments and all of the header pipe segments being thus surrounded, optimum performance results from a further provision of including apertures along the lateral lengths of the inside pipe segments, with a steel wool-type wrapping around those apertures within the enclosed space. With the contained pipe segments being centered within the overlying surrounding pipe segments, then, the optimum performance follows—although enhanced results follow with just the exhaust pipe segments being surrounded, with or without the steel wool-type wrapping—or with just each of the header pipe segments being enclosed, with or without its own further wrapping. Essentially an exhaust system of “pipe segments within pipe segments” results, which serves in directing the exhaust gas flow and in reducing the “back-pressures” associated with conventional muffler component systems which typify the prior art. As with the individual pipe segments for the exhaust pipe and for the header pipes, the individual pipe segments of the further surrounding pipes of the invention could be secured by welding, for example. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features of the present invention will be more clearly understood from a consideration of the following description, taken in connection with the accompanying drawings, in which: 
       FIG. 1  pictorially illustrates the four header pipes that typically come off one side of a V-8 automotive internal combustion engine by coupling to the exhaust cylinder heads; 
       FIG. 2  is a front view of a collector constructed in accordance with the teachings of the invention described in my U.S. Pat. No. 5,199,258; 
       FIG. 3  schematically shows the side view of the collector of  FIG. 2 ; 
       FIG. 4  pictorially illustrates the exhaust system of an automotive vehicle in accordance with the teachings of the invention set out in my U.S. Pat. No. 5,144,799; and 
       FIGS. 5–8  are illustrations helpful in understanding the overlying surround pipe segment constructions of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In  FIG. 1 , the engine cylinder heads on one side of a V-8 engine are represented by the notations  10 ,  12 ,  14  and  16 . The collector into which the individual header pipes will couple is shown at  18 , with the four individual header pipes being generally shown as  20 ,  22 ,  24  and  26 . As will be appreciated, because of the other components and systems present in the engine compartment of the vehicle, the header pipes—tailored for a particular vehicle manufacture, model and year—are not all the same length, and not all cut the same way, but are selected of a length, cut and angle so as to provide the needed bend and clearance in eventually coupling with the collector  18 . Thus, and for purposes of illustration, the header pipe  20  is shown as comprising four pipe segments  30 ,  31 ,  32 ,  33  with the segment  33  physically being in front of a portion of the segment  43 , which together with the segments  40 – 42  make up the header pipe  24 . As will be obvious from  FIG. 1 , the overall length of the pipe segments  30 – 33  of header pipe  20  is less than the overall length of the pipe segments  40 – 43  of the header pipe  24 . 
   Also shown in  FIG. 1  is a typical third header pipe  22 , comprised of four pipe segments  50 ,  51 ,  52  and  53 , with the pipe segment  53  being physically placed in front of a portion of the pipe segment  63  of the header pipe  26 , having three other pipe segments at  60 ,  61  and  62 . As will be apparent, the overall length of segments  50 – 53  of header pipe  22  will be seen to be less than the overall length of the pipe segments  60 – 63  of the header pipe  26 . As will also be appreciated from this illustration, the overall length of the header pipe  26  is greater than the overall length of the header pipe  24 —which, in turn, is greater than the overall length of the header pipe  22 , and with the header pipe  20  being of the shortest overall length of the four pipes. In a typical construction, the outside diameters are all selected substantially equal, and in the order of 2″. 
   Referring now to  FIG. 2 , the front view of the collector  18  there shown illustrates the collector as having a plate  70  internally secured to the collector, as by an appropriate welding, along with four apertures or ports  72 ,  74 ,  76  and  78 . As is also shown—and as will be more clearly understood from the following FIG.  3 —, secured to each of the apertures  72 ,  74 ,  76  and  78  are four, smaller collector pipes  80 ,  82 ,  84 ,  86 , each of which has an inner diameter slightly greater than the outer diameter of the header pipes  20 ,  22 ,  24 ,  26 —which, for header pipes of 2″ outer diameter might be 2⅛″ inner diameter for each collector pipe. 
   As will be apparent, and because of this difference in respective diameters, the header pipes  20 ,  22 ,  24  and  26  are each able to slide within the collector pipes  80 ,  82 ,  84  and  86 , in easing their respective insertions and in facilitating their respective removals, one from another. Thus, when imagining the rotation of the collector  18  inwardly of the plane of the paper and to the right of the position shown in  FIG. 2 , one arrives at the orientation shown in  FIG. 3 , wherein the header pipe  24  would be oriented to slide within the upper-left aperture  72  (where collector pipe  80  is secured), while the header pipe  20  would be oriented to slide within the upper right aperture  74  (where collector pipe  82  is secured). In like manner, and with this rotation and orientation, the header pipe  26  would be oriented to slide within the lower-left aperture  76  (where collector pipe  84  is secured), and header pipe  22  would be oriented to slide within the lower-right aperture  78  (where collector pipe  86  is secured). As will be appreciated, because of the clearance of the header pipes with the collector pipes where they are coupled together, it becomes then but a simple matter to slidably remove the header pipe from its respective collector input pipe, and to then adjust the header pipe out-of-the-way when it is desired to service the various components, systems and/or assemblies of the vehicle previously obstructed from access by the header pipes in prior art configurations. 
   In accordance with my U.S. Pat. No. 5,199,258 invention, and as is schematically illustrated in  FIG. 3 , the individual collector pipes  80 ,  82 ,  84  and  86  are selected of a predetermined length so as to substantially equalize the total length of each header pipe and fitted collector pipe, measured from the engine heads to the output of the collector  18 . Thus, for the case where the length of the header pipe  20  is the shortest of the lengths of the header pipes  20 ,  22 ,  24  and  26 , the collector pipe  82  in connection with which it slides, would have the longest length of the four collector pipes  80 ,  82 ,  84  and  86 . In corresponding manner, where the length of the header pipe  26  is as shown in  FIG. 2  to be of the greatest length of the four header pipes employed, the collector pipe  84  in which it slidably is inserted would be of the shortest length of the four collector pipes. In similar fashion, as the header pipe  24  is, as shown in  FIG. 2 , of a greater length than the header pipe  22 , in  FIG. 3 , correspondingly, the length of the collector pipe  80  is shown to be shorter than the length of the collector pipe  86 . In establishing these relative lengths, such invention carried through the concept that best engine performance and least engine “ping” resulted from having the overall individual lengths of the individual header pipes and their respective collector pipes all be substantially equal. 
   As is thus far described, it will be understood that the collector  18  can thus slide toward, or away from the engine, as to the left or to the right, correspondingly, in  FIG. 3 . Testing showed that by sliding the collector  18  forwardly (as to the left in  FIG. 3 ), more engine torque is available, and the time for which exhaust gases take to travel from the engine to the system&#39;s exhaust coupling via the collector output is shortened. Testing has similarly showed that by sliding the collector  18  rearwardly (i.e., to the right in  FIG. 3 ), a longer period of time is taken for exhaust gases to travel to couple to the vehicle&#39;s exhaust system, providing a higher rpm, in holding the horsepower longer, but a slightly-less torque. Analysis showed that by varying the distance that the collector  18  was moved forwardly or rearwardly, an adjustable control of the torque and of the horsepower could be attained, in order to meet vehicle objectives of the user. 
   As generally set out in my other U.S. Pat. No. 5,144,799, the exhaust system from the motor vehicle is most oftentimes bent in various odd-shapes so as to clear its rear housing, its power steering systems, and its other control installations to meet with the tailpipe in channeling the exhaust flow away. As with the teachings of my U.S. Pat. No. 5,199,258, my U.S. Pat. No. 5,144,799 taught that advantages could follow by cutting the exhaust pipe from the muffler to the tailpipe into similar individual sections to clear obstructions, rather than being bent into position. By providing a “straight” exhaust flow in this manner through shortening the path the exhaust gas takes to the outside atmosphere, a degree of calibration was available to likewise control the torque, horsepower, manifold vacuum and engine temperatures associated with the system in use. As therein set forth, and as shown in  FIG. 4  herein, the odd-shaped, bent piping exhaust assembly coming off the muffler  125  is replaced by a series of individually connected short pipe segments  154 ,  156 ,  158 . interconnected to avoid the rear housing and its components, and to exhaust the gases from the motor vehicle (either as shown), or by a separate tailpipe (not shown). Although specifically shown as comprising three separate pipe segments, the pipe exhaust assembly  152  could consist of fewer or less separate pipe segments, as the circumstances warrant—the understanding being, however, that individually cut pipes provide superior performance than to utilize an odd-bent shape, and represents an improvement not only in the ease of manufacture, but in enhanced operation of performance. Specifically, and as such patent indicated, experimentation showed that the use of individually cut pipe segments decreased the path which the exhaust gases flowed in order to leave the automotive vehicle, lessening the chances for the engine “loading-up” and “chugging” or choking in its performance. 
   As will be readily understood by those skilled in the art, to facilitate the interconnections of the pipe segments  154 ,  156 ,  158 —as well as to join them with the output of the muffler  125  which couples to the output end of the collector  18 —the pipe segments  154 ,  156  and  158  are both rotated and cut at various angles, and then welded together to clear the rear housing, and its components. What the length for each of the pipe segments  154 ,  156  and  158  might be, and upon what angle the cutting depends for joining the individual segments together, all depend upon the rear housing configuration. In constructing the arrangement, it will be understood that once one pipe segment is cut, it is rotated until the proper angle is obtained where it is to be joined with the next pipe segment, and with all the segments then being welded together. Where the muffler  125  is located along the line, and whether any tailpipe is to be employed or not (as my U.S. Pat. No. 5,144,799 points out) will obviously depend upon the specific application for the exhaust system described. In this arrangement, the pipe segments  154 ,  156  and  158  could be of a substantially 3″ outer diameter. 
   While testing showed that an internal combustion automotive engine system designed with these individual pipe segments being cut at these individual lengths, angled together in their individual amounts and then welded together, perform quite adequately, one limitation continued to be the “back-pressure” created by the muffler. This, however, can be obviated in accordance with the teachings of the present invention, in which the muffler is entirely eliminated to begin with—, and by redesigning the flow directing pipe segments to themselves serve as the “muffler” for the exhaust. As will be seen from the description which follows, this is accomplished, generally, by the providing of a series of apertures along the lengths of the individual pipe segments of the header pipes and/or providing apertures along the lengths of the rear-housing pipe segments (to be coupled directly to the output of the collector instead of to any included muffler)—and, then by enclosing and containing the individually apertured pipe segments within a surrounding shield or pipe similarly cut and angled so as to overlie the individual segments in corresponding alignment to clear the various undercarriage components of the vehicle. “Pipe segments within pipe segments” thus result, with optimum performance in the nature of improved torque, improved horsepower, enhanced fuel economy, and reduced “back-pressures” following when the apertures are provided both in the exhaust pipe segments and in each of the header pipe segments. Enhanced performance in these areas, although slightly less than optimum, has been also found to result where the apertures are provided either in just the exhaust pipe segments, or just in each of the header pipe segments. With the pipe segments previously dimensioned, the surrounding pipe segments of the invention for that of the header pipe segments could be of a 2½″ inner diameter while the surrounding exhaust pipe segments could be of a 4″ inner diameter. Appropriate “spacers” could be provided on the internal pipe segments so as to center them within the surrounding shield segments in providing the needed “muffling”, which could be increased still further by a steel wool wrapping around the apertures within the space between the overlying segments in providing a very highly effective and efficient muffled environment. 
   Thus, referring to  FIGS. 5–8 , the internal pipe segments of the exhaust pipe and/or of the header pipe are generally shown as  202 ,  204 ,  206  and  208  of the pipe  200 —apertured in a preferred embodiment along their entire lateral lengths, as at  220 . In like manner, the surrounding pipe of like cut and angled segments  302 ,  304 ,  306  and  308  is shown at  300  with the individual segments of both pipes  200  and  300  being cut, angled and secured together as generally shown at  400 . Spacers shown at  402  in  FIG. 6  at 120° spaced intervals about the circumference of the pipe  200  serve to center the pipe  200  within the surrounding pipe  300 , while a steel wool-type wrapping  404  is wound around the various apertures of the inside pipe  200  as shown in  FIG. 7 . The end view of  FIG. 8  illustrates the surrounding of the pipe  200  within the pipe  300 , centered and with the steel wool-type wrapping in place. 
   In accordance with the invention, this “pipe-within-a-pipe” combination could be utilized either for just the exhaust pipe, of the automotive vehicle, for just the header pipe connections from the engine to the input end of the collector, or as both—which provides the optimum performance. Utilizing the teachings for only the exhaust pipe construction, or for only the header pipe constructions, reduces performance somewhat, but still enhanced with respect to that which characterizes conventional muffler use. Testing has shown that to be the same situation with the wrapping of the individual surrounded apertures—namely, leaving the apertures uncovered provides a performance characteristic greater than with the conventional muffler, and even more with the individual apertures being covered. In a preferred construction of the invention, the inner diameter of the surrounding pipe segments when enclosing the header pipe segments may be of the order of 2½″ when the outer diameter of the header pipe segments is of substantially 2″. In like manner, an inner diameter for the surrounding exhaust pipe segments might be of some 4″ with an outer diameter of its contained pipe segments being 3″. 
   While there have been described what are considered to be preferred embodiments of the present invention, it will be readily appreciated by those skilled in the art that modifications can be made without departing from the scope of the teachings herein. For at least such reason, therefore, resort should be had to the claims appended hereto for a true understanding of the scope of the invention.