AUTOMOTIVE EXHAUST SYSTEM

Abstract

The automotive exhaust system includes a plurality of exhaust pipes that feed into a common collector. The collector includes a venturi at the point where the exhaust gases enter the collector from the multiple exhaust pipes. The exhaust gases accelerate through the venturi by virtue that the venturi has a cross-sectional area smaller than that of the exhaust pipes and the collector. A plurality of vanes located in the venturi further accelerate the exhaust gases into a spinning vortex along the interior surface of the main body of the collector to efficiently and quickly expel the exhaust gases out from within the automotive exhaust system. The diameter of the venturi relative to the collector is specific to each diameter of tubing as matched with the corresponding vehicle specifications.

Description

BACKGROUND OF THE INVENTION

The present invention relates to an automotive exhaust system. More particularly, the invention relates to an automotive exhaust system having an improved collector that accelerates the expulsion exhaust gases out the tailpipe.

Over the years, various exhaust systems have been designed to improve the efficiency and power output of four-stroke internal combustion (“IC”) engines. Improvements in engine components and “super tuning,” as is more typically done in racing systems, have produced significant increases in engine power, especially with respect to the exhaust system. The efficiency of expelling exhaust gases resultant from the combustion process in an IC engine is important to the overall efficiency of the engine. For example, increasing exhaust system efficiency can reduce fuel consumption of the IC engine while maintaining and improving output power.

The exhaust gases in an IC engine exit the piston cylinder chamber through an exhaust orifice and into an exhaust manifold. Typically, more than one cylinder in multiple cylinder IC engines (e.g. four-cylinder, six-cylinder, eight-cylinder, etc.) share the same exhaust manifold. Here, exhaust gases travel through the exhaust orifice and flow into a common pipe toward the catalytic converter, the muffler and eventually out through the tailpipe. The piston cylinders may be subject to back pressure because the exhaust gases from one cylinder build up in the exhaust manifold and can affect the next cylinder that opens to use the exhaust manifold.

For example, most automobiles have an IC engine that uses a four-stroke cycle to produce the energy needed to operate the vehicle. The four strokes refer to intake, compression, combustion (power) and exhaustion of waste gases resultant from the compression process. Initially, a mixture of fuel and air is forced into the piston cylinder during the intake stroke. The piston inside the cylinder compresses the fuel/air mixture during the compression stroke. Thereafter, the combustion stroke takes place by igniting the compressed fuel/air mixture with a spark plug. The fuel burns and expands during this stroke to generate the power necessary to move the piston. An exhaust valve opens at the beginning of the exhaust stroke to allow the piston to push out the exhaust gases from within the cylinder. The intake, compression and exhaust strokes are all required to enable the power stroke. These strokes all require energy and thereby reduce the amount of energy that may be used to operate the vehicle. This directly affects vehicle performance, fuel consumption, efficiency and power.

The exhaust valve opens during the exhaust stroke to enable the exhaust gases produced during the combustion stroke to exit the cylinder through the exhaust orifice into the exhaust manifold. The exhaust gases preferably efficiently exit the cylinder at high velocity. Any exhaust gases remaining in the exhaust system may have a tendency to stagnate or even reverse direction due to a change in vacuum. This negative vacuum where exhaust gases are pulled back toward the piston cylinders, may subsequently exert a resistive force on the next round of escaping exhaust gases when the exhaust valve of the next cylinder opens. Ultimately, this force may exert back pressure on the piston, thereby preventing efficient escape of the exhaust gases from within the cylinder. Additional power is wasted if the piston has to push against the back pressure to force the exhaust gases out. This action adversely causes engine torque to fall below its optimum value and the engine subsequently loses power and performance.

An exhaust header is a bolt-on engine accessory designed to improve engine performance by making it easier for the IC engine to push exhaust gases out from within the cylinders. Basically, the exhaust header functions to eliminate back pressure in the exhaust manifold by connecting multiple pipes to multiple exhaust valves in the IC engine, instead of relying on a single, common pipe. First, multiple exhaust pipes alone improve the flow of exhaust gases exiting the cylinder by efficiently providing a larger per-cylinder area through which the exhaust gases may exit. Second, each cylinder gets its own exhaust pipe, instead of sharing a common manifold. The multiple pipes come together into a larger pipe called a collector. Ideally, each pipe is similarly cut and bent to the same length so that the exhaust gases from the various cylinders arrive in the collector spaced out equally to eliminate back pressure generated by the cylinder sharing the collector. Efficient removal of the exhaust gases from the point where the exhaust gases are collected in the collector further enhances the efficiency of the exhaust system such that the vehicle may maintain performance and power. But, the prior art fails to disclose a system for efficiently and expeditiously expelling exhaust gases through the collector and out the end of the tailpipe.

Thus, there exists a significant need for an improved automotive exhaust system capable of accelerating exhaust gases through a collector and out through the end of a tailpipe. Such an improved automotive exhaust system should include multiple exhaust pipes that feed into a common collector, should be capable of accelerating the exhaust gases at the point of entry into the collector from the multiple exhaust valves, and should further be capable of creating a vortex of spinning escaping exhaust gas within the collector to quickly and efficiently expel the exhaust gas through the end of the tailpipe and into the atmosphere. The present invention fulfills these needs and provides further related advantages.

SUMMARY OF THE INVENTION

The improved automotive exhaust system of the present invention includes a plurality of exhaust pipes at the proximal end that join into a common collector at the distal end. The collector includes a venturi at the point of entry of the exhaust gases from the multiple exhaust pipes. The venturi has a cross-sectional area smaller than that of the cross-sectional area of the pipes or the cross-sectional area of the main body of the connector. In turn, exhaust gases accelerate through the venturi and into the main body of the collector. Moreover, the venturi includes a plurality of vanes that further accelerate the exhaust gases into a spinning vortex along the interior surface of the collector to quickly and efficiently expel the exhaust gases out the end of the tailpipe. The diameter of the venturi relative to the collector is specific to each diameter of tubing as matched with the corresponding vehicle specifications.

Other features and advantages of the present invention will become apparent from the following more detailed description, when taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is a perspective view of an improved automotive exhaust system in accordance with the present invention;

FIG. 2 is an end view of a collector integral to the automotive exhaust system;

FIG. 3 is an end view of a plurality of exhaust pipes feeding into the collector; and

FIG. 4 is a schematic view illustrating the internal flow of exhaust gases through the exhaust pipes and the collector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the drawings for purposes of illustration, the present invention for an improved automotive exhaust system is referred to generally by the reference number 10. The improved automotive exhaust system 10 generally includes a plurality of exhaust pipes 12 that feed into a collector 14 through a venturi 16. FIG. 1 illustrates four exhaust pipes 12 converging into a single collector 14. Other embodiments may include any one of a number of plurality of exhaust pipes 12 that feed into a single collector 14, such as two, three, five, etc., in accordance with the present invention. In this respect, the exhaust pipes 12 are shown in FIG. 1 sectioned off from an exhaust header for purposes of describing the improved automotive exhaust system 10 of the present invention. A person of ordinary skill in the art will readily recognize that the exhaust pipes 12 extend back into the exhaust header that couples to the IC engine piston cylinders. That is, during the exhaust stroke in a four-stroke IC engine, exhaust gases exiting the piston cylinder through the exhaust orifice enter the exhaust header and travel through the exhaust pipes 12 into the collector 14. The exhaust pipes 12 may each correspond to a single, or less preferably, multiple exhaust orifices in an IC engine. For example, the automotive exhaust system 10 illustrated in FIG. 1 having four exhaust pipes 12 may correspond to a four-cylinder IC engine. Each of the exhaust pipes 12 would be coupled to the exhaust orifice of each piston cylinder in the IC engine.

Exhaust gas traveling through the exhaust pipes 12 enter the venturi 16 before entering the collector 14. As best shown in FIG. 1, the venturi 16 is smaller in diameter than either the exhaust pipes 12 feeding therein or the collector 14. To satisfy the equation of continuity according to Bernoulli's Principle, the velocity of the exhaust gases traveling through the venturi 16 must increase as the area through which the exhaust gases travel is smaller relative to the exhaust pipes 12 and the collector 14. The acceleration of exhaust gases through the venturi 16 better expels the exhaust gases from the exhaust pipes 12, thereby preventing potential back pressure into the exhaust pipes 12, the exhaust header or the exhaust manifold. Similarly, the pressure of the exhaust gases traveling through the venturi 16 decreases due to the increase in velocity. Of course, the velocity of the exhaust gases slows down in the collector 14 such that a simultaneous increase in pressure is observed due to the larger diameter of the collector 14 relative to the venturi 16. The smaller diameter of the venturi 16 effectively limits any potential back pressure due to exhaust gases slowing down in the collector 14, especially in view of the accelerated exhaust gases passing through the venturi 16. That is, the automotive exhaust system 10 of the present invention limits back flow, or reverse vacuum, because the venturi 16 is capable of accelerating the exhaust gases out of the exhaust pipes 12 and into the collector 14.

FIGS. 2 and 3 illustrate a set of exhaust vanes 18 disposed within the venturi 16, intermediate to the exhaust pipes 12 and the collector 14. Placement of the vanes 18 within the venturi 16 are also shown in the schematic view of FIG. 4. The vanes 18 located along the wall of the venturi 16 further accelerate and turn the exhaust gases traveling from the exhaust pipes 12 to the collector 14. That is, the vanes 18 create a vortex of spinning exhaust gases along the outer edges of the wall of the venturi 16, which more quickly draws the exhaust gases through the center of the venturi 16. In turn, this further acceleration of the exhaust gases helps the performance of the automotive exhaust system 10. As best shown in FIGS. 3 and 4, the vanes 18 are arced to match the interior wall of the venturi 16. The vanes 18 are also centered downstream relative to each exhaust pipe 12 to best deflect and direct the exhaust in the correct direction. The vanes 18 may also be angled relative to the adjacent wall within that arcuate section, depending on the diameter of the venturi 16 and the size of the vanes 18. The spinning exhaust then enters the collector 14, which is preferably manufactured in a diameter of one and one-quarter to three inches, in one-eighth increments in size.

FIG. 4 is a schematic view illustrating exhaust gases, identified by the directional arrows therein, traveling through the various exhaust pipes 12, through the venturi 16 and into the collector 14. The velocity of the exhaust gas increases from the exhaust pipes 12 into the venturi 16. The higher velocity exhaust gases are redirected by the vanes 18 such that the exhaust gases begin spinning within the venturi 16 and into the collector 14. The vortex of spinning exhaust gases along the outer edges of the venturi 16 and the collector 14 reduces the amount of turbulence otherwise experienced in traditional automotive exhaust systems. Reducing the quantity of turbulence effectively increases the efficiency of expelling the exhaust gases out through the collector 14. Efficient removal of exhaust gases from within the exhaust system translates into increased performance of the IC engine. In the realm of automobiles, the operator may experience more power, better fuel efficiency and better response time of the engine. This is all due to the performance of the automotive exhaust system 10 of the present invention through its ability to accelerate and efficiently move the exhaust gases through the venturi 16 and out through the collector 14. Of course, the size of the exhaust pipes 12, the collector 14, the venturi 16, and the size, shape and curvature of the vanes 18 may vary depending on the application of the automotive exhaust system 10 of the present invention. For example, larger automobiles may require larger piping. Alternatively, the ratio of the diameter of the venturi 16 relative to the exhaust pipes 12 and the collector 14 may also vary according to the desired application. Requirements may vary depending on the make and type of the vehicle with which the automotive exhaust system 10 would be fitted. The present invention disclosed herein has been directed to an automotive exhaust system. It is to be appreciated that the exhaust system is applicable to all forms of internal combustion exhaust systems and is not intended to be limited to the precise application described herein.

Fluidity of the automotive exhaust system is an important aspect to maximize performance of the internal combustion engine. Rough transitions and unnecessary obstructions increase internal backpressure and rob efficiency. In an exemplary embodiment, the venturi 16 and collector 14 are formed from a single tube of material through specialized tooling. Next, the vanes are welded inside and thereafter the plurality of exhaust pipes are welded thereby forming the exhaust system described herein. This process results in a smooth form for the exhaust to flow through and results in increased performance. Referring to FIG. 1, the venturi 16 is defined having a converging section 20, a reverse radius section 22 which is the actual venturi, a diverging section 24, and a distal radius section 26. The converging section 20 is typically manufactured at 20 degrees relative to the axis of the incoming exhaust pipe 12. The reverse radius section 22 is typically manufactured from a reverse radius of 2 times the diameter of the exhaust pipes 12. The diverging section 24 is typically manufactured at a 7-10 degree angle relative to the axis of the exhaust pipe 12. The distal radius section 16 is typically manufactured at a radius 2 times the diameter of the exhaust pipe 12. Other variations of radii and angles may be used without departing from the scope of this invention.

Although several embodiments have been described in detail for purposes of illustration, various modifications may be made to each without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.

Claims

1. An exhaust system, comprising:

a plurality of exhaust pipes at a proximal end of the exhaust system for receiving internal combustion engine exhaust, the exhaust pipes having a combined cross-sectional area;

a collector at a distal end of the exhaust system and having a cross-sectional area;

a venturi disposed between and fluidly connecting the exhaust pipes and collector, wherein a cross-sectional area thereof is less than either the collector cross-sectional area or the combined exhaust pipes cross-sectional area; and

a vane fixed to an inner wall of the venturi.

2. The exhaust system of claim 1, wherein the vane comprises an arced vane which matches the inner wall of the venturi.

3. The exhaust system of claim 1, wherein the vane is angled relative to the adjacent inner wall of the venturi.

4. The exhaust system of claim 1, comprising a plurality of vanes fixed to the inner wall of the venturi.

5. The exhaust system of claim 4, comprising at least one vane corresponding to each exhaust pipe.

6. The exhaust system of claim 5, wherein each vane is approximately centered relative to its corresponding exhaust pipe.

7. The exhaust system of claim 1, wherein the collector and venturi are integrally formed from a single piece of tubing.

8. An exhaust system, comprising:

a plurality of exhaust pipes at a proximal end of the exhaust system for receiving internal combustion engine exhaust, the exhaust pipes having a combined cross-sectional area;

a collector at a distal end of the exhaust system and having a cross-sectional area;

a venturi disposed between and fluidly connecting the exhaust pipes and collector, wherein a cross-sectional area thereof is less than either the collector cross-sectional area or the combined exhaust pipes cross-sectional area; and

at least one vane corresponding to each exhaust pipe fixed to an inner wall of the venturi.

9. The exhaust system of claim 8, wherein the vane comprises an arced vane which matches the inner wall of the venturi.

10. The exhaust system of claim 8, wherein the vane is angled relative to the adjacent inner wall of the venturi.

11. The exhaust system of claim 8, wherein each vane is approximately centered relative to its corresponding exhaust pipe.

12. The exhaust system of claim 8, wherein the collector and venturi are integrally formed from a single piece of tubing.

13. An exhaust system, comprising:

a plurality of exhaust pipes at a proximal end of the exhaust system for receiving internal combustion engine exhaust, the exhaust pipes having a combined cross-sectional area;

a collector at a distal end of the exhaust system and having a cross-sectional area;

a venturi disposed between and fluidly connecting the exhaust pipes and collector, wherein a cross-sectional area thereof is less than either the collector cross-sectional area or the combined exhaust pipes cross-sectional area; and

at least one vane corresponding to each exhaust pipe fixed to an inner wall of the venturi, wherein each vane is approximately centered relative to its corresponding exhaust pipe and comprises an arced vane which matches the inner wall of the venturi and is angled relative to the adjacent inner wall of the venturi.