Muffler having fluid swirling vanes

Abstract

A muffler for an internal combustion engine has a casing forming an expansion chamber therein. An inlet duct is connected to the casing and projects into the expansion chamber and discharges exhaust fluid into the expansion chamber. The casing tapers in an upstream direction to form a pocket for receiving reverse flow of the exhaust gases and to minimize reverse flow from flowing back into the inlet duct in an upstream direction. In the discharge end of the inlet duct are a set of primary vanes and a set of secondary vanes. The vanes are secured to the walls of the duct and extend radially toward the central area of the duct. The vanes are angled in order to deflect the exhaust fluid flow into a swirling movement as it is discharged into the expansion chamber and maintains that swirling movement while passing out of the casing through the outlet duct.

Description

BACKGROUND OF THE INVENTION [0001] The present invention relates generally to mufflers for internal combustion engines of the type commonly used in motor vehicles. More particularly, the present invention relates to such mufflers which provide improved engine combustion efficiency resulting in improved performance and reduced toxic exhaust emissions levels. [0002] Motor vehicles utilizing internal combustion engines continue to be the favored form of transportation to most people in the developed countries of the world. This is in spite of their many disadvantages the more important of which include toxic exhaust emissions and exhaust noise. Although mufflers can substantially reduce or perhaps even eliminate the exhaust noise, it is commonly believed that they do so at the expense of reduced power output and reduced fuel economy. [0003] Designers of exhaust systems have recognized that improving the effectiveness of exhaust gas flow out of the engine can provide improved combustion...

AI Technical Summary

Benefits of technology

[0011] It is another object of the present invention to provide a muffler which prevents reverse flow of exhaust fluid therein.

[0025] The muffler of the present invention thus provides an exhaust system component that prevents or reduces reverse flow of the exhaust fluid as well as enhancing fluid flow through the exhaust system. The present invention thus eliminates or minimizes hesitation during acceleration thereby improving performance and improves fuel economy by ensuring a fresh air / fuel mixture in the combustion chamber.

Problems solved by technology

This is in spite of their many disadvantages the more important of which include toxic exhaust emissions and exhaust noise.

Although mufflers can substantially reduce or perhaps even eliminate the exhaust noise, it is commonly believed that they do so at the expense of reduced power output and reduced fuel economy.

However, such systems require retuning of the engine and replacement of major engine system components and are thus impractical for many motor vehicle owners.

Two primary disadvantages of dissipative mufflers are that they lose their effectiveness over time and are expensive to manufacture.

Moreover, dissipative mufflers do not produce good low frequency sound attenuation.

A reactive muffler is inexpensive to manufacture and provides good low frequency sound attenuation but has the disadvantage of producing high backpressure.

Variations on these two basic designs have sought to produce desired sound attenuation without substantially or unacceptably increasing the back pressure on the engine since, as is commonly known, excessive muffler induced back pressure will substantially compromise engine combustion efficiency and reduce engine performance.

However, utilization of such structures increases the complexity, cost and size of the exhaust system.

But, a large exhaust system is often very undesirable as motor vehicle space may be limited and ground clearance may need to be high especially for sport utility vehicles.

Nevertheless, its size and shape render it unsuitable for some types of motor vehicles.

Such types of mufflers, however, have inordinate complexity.

However, such designs are not very effective at this because since the tubes are straight tubes the major portion of the gas stream flows through and out of the tube and only a small portion flows out through the muffling apertures.

However, the Chen pipe is only a part of a muffler and many types of muffler casings would not be suitable for such a pipe.

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