US3516247A - Collector for automobile exhaust system - Google Patents

Description

June 23, 1970 J. KNOX, JR

COLLECTOR FOR AUTOMOBILE EXHAUST SYSTEM Filed June 24. 1968 .W Ky 02w 6 TX N i J A United States Patent 3,516,247 COLLECTOR FOR AUTOMOBILE EXHAUST SYSTEM Leon J. Knox, Jr., Los Angeles County, Calif., assignor to California Tube Products, Inc., Burbank, Calif. Filed June 24, 1968, Ser. No. 739,515 Int. Cl. F02b 27/04 US. Cl. 60-32 2 Claims ABSTRACT OF THE DISCLOSURE The tuned exhaust system includes a header pipe appropriately connected to receive exhaust gas from each cylinder and is of predetermined length. The outer ends of each header are received within a one piece collector having internal conduiting means to conduct exhaust gases via a single outlet opening to a muffler and tail pipe assembly.

BACKGROUND OF THE INVENTION The present invention pertains generally to automotive exhaust systems, and, more particularly, to a coupling unit or collector for relating a plurality of tuned exhaust headers to a muffier and tail pipe assembly.

It is conventional to provide separate conduits or header pipes for leading exhaust gases from the individual cylinders of an internal combustion engine to a muffler and tail pipe where each such header pipe is of prescribed capacity and length to permit optimum operation of the engine. Such tuned exhaust systems rely essentially upon removing the exhaust gases without increasing the exhaust pressure which would adversely affect the engine horsepower. More particularly, in a satisfactory tuned exhaust system as exhaust gas from one cylinder is being removed, a reduction in internal pressure below external air pressure is achieved which aids in the removal of the gases from the cylinder that is next in order to fire. This effect is frequently referred to by the term scavenging.

Tuned exhaust systems have been of necessity constructed in complicated configurations, with the various individual header pipes being connected together by Welding, which can be both expensive as well as difficult to accomplish. In explanation, the problem essentially in making a tuned exhaust system. is to provide a precise length of header pipe for each cylinder in order to produce the above mentioned pressure reduction on the removal of exhaust gas to assist in removal of exhaust gas from the other cylinders, and this can necessitate a relatively long pipe for each cylinder. These header pipes must,

therefore, be bent into curved configurations to keep them within a conveniently sized volume available in the automobile. It is also desirable that the precisely measured length header pipes, which are folded about One another,

SUMMARY OF THE INVENTION By the practice of the present invention there are provided a plurality of individual header pipes of prescribed length, one end of which is connected via a fitting to the exhaust manifold to receive the exhaust gases from the respective cylinders. A one-piece cast collector is provided 3,516,247 Patented June 23, 1970 "ice with openings for individually receiving the other ends of each of the header pipes therewithin for conduiting exhaust gases to a single outlet to exit to the atmosphere.

DESCRIPTION OF THE DRAWING FIG. 1 illustrates a tuned exhaust system of the present invention.

FIG. 2 is a sectional view of the exhaust collector of the invention providing interconnection of the header pipes.

FIG. 3 is a further sectional view of the exhaust collector of FIG. 2 taken along the line 33.

FIG. 4 is another sectional view of the exhaust collector taken at an angle of to that of FIG. 3 and along the line 4-4 in that figure.

FIG. 5 is a slightly reduced depiction of the exhaust collector of the invention viewed directly into its outlet.

DESCRIPTION OF A PREFERRED EMBODIMENT FIG. 1 of the drawing shows, in stylized form, an internal combustion engine identified generally as at 10 which for purposes of description here will be considered to have four cylinders. Each of the cylinders is provided with an exhaust manifold and appropriate outlet fittings as shown at 11 and 12. Onto the fittings 11 and 12 there are connected exhaust conduiting means or header pipes 13-16, via appropriately dimensioned matching fittings 17 which are only illustrated for the header pipes 13 and 14. Each header pipe is constructed of a length and internal volume precisely determined as will be described further below. Also, for convenience of placement and to conserve space, each of the header pipes is formed into a curved configuration reducing the total length of extension and thereby utilizing optimally minimum space.

The outer end of each header pipe is received within an appropriately sized opening in a collector 18 having a single outlet from which exhaust gases are directed into the atmosphere.

It is the general principle and theory of operation of the present tuned exhaust system to receive exhaust gases from each cylinder via the associated conducting means or header pipes 13-16 and direct the gases, as they are sequentially received, into a mother and tail pipe assembly 19 without producing an increased pressure against which any other subsequent exhausting gases would have to move. In fact, the various elements of the exhaust system coact in such manner that as exhaust gas from each cylinder leaves the tail pipe 20 it produces a reduced pressure within the collector 18 which enhances scavenging of gasses which are at that same time entering a header pipe from the cylinder next in firing order. It can be shown that by reducing the pressure against which the exhaust gases of an internal combustion engine must move, a corresponding increase in horsepower of the engine is achieved.

Turning now particularly to FIG. 2, the collector means 18 is seen to be of one-piece construction with walls defining four externally directed openings 21-24 for receiving, respectively, the outer ends of header pipes 13-16. These openings are arranged in two pairs which are aligned and which face upwardly away from each other with their axes generally in the same plane and with the inner ends of the header pipes abutting against shoulders 25 formed on the inner walls of the openings. By means of this internal shoulder, uniformity in the total length of path the exhaust gas must follow is maintained for each header pipe.

Referring also to FIGS. 3 and 4, each entrance opening 21-24 is seen to open into a separate passage or chamber, with all such chambers communicating with a single outlet. For example, the gases exiting from header pipe 21 pass into a chamber 26 formed by a curved outer wall 27 that is integral with front and side inner walls 28 and 29, respectively. These walls act upon pressurized exhaust gas moving outwardly of the header pipe 21 into the chamber 26 to direct it toward the viewer in FIG. 2.

Each of the chambers into which the headers empty via respective openings 2124 has a common outer back wall 30 and otherwise is identical to 26. Also, all of them are in communication with a common exit fitting 31 whose exit orifice 32 is indicated in dashed line depiction in FIG. 2. This outlet opening 32 has its axis perpendicular to the plane of the axes of the inlet openings 2124, and is centrally located relative to the inlet openings. As best shown in FIG. 2, the exhaust gas coming from any particular header pipe enters into the exit ori-fice 32 through its own quadrant with the walls 28 and 29 restricting the gas movement into other chambers 26. This feature is further depicted in FIG. 3 where the wall 28 is seen to extend outwardly away from back wall 30 between adjacent chambers 26 for deflecting and directing gases into the exit orifices 32.

In operation, engine exhaust gases are provided via the different header pipes in a sequential manner depending upon the particular firing order prescribed for the engine. The volume capacity and total length of each header pipe and collector 18 is such that at some predetermined rotative velocity of the engine exhaust gas provided from a particular cylinder is emerging from the tail pipe 20 at substantially the same time that the exhaust valves of the cylinder next in firing order are opening. In this manner the interior portions of the header system are periodically placed at a lowered pressure, scavenging exhaust gases and thereby enhancing operation of the engine and increasing its power. The exact total length of conduiting for the exhaust gases must be determined for each type of engine in order to produce optimum results.

By the practice of the present invention the previously encountered ditficult and complex manufacturing welding operations to relate a plurality of header pipes into a common conduiting system has been avoided. It is now possible to construct the headers of appropriate length and configuration with plain ends that are simply received within the openings in the collector 18. Additionally, it is possible through practice of this invention to replace any one header pipe that may become damaged by merely removing the bolts retaining the fittings 17 and 11 to one another, remove the end of the header pipe from the collector and substitute a new one. Such a substitution was simply not possible in prior art systems since the entire complex of piping was in a single integral 4 unit and damage to any one part meant that the entire assembly had to be replaced.

What is claimed is:

1. In a collector for an internal combustion engine exhaust system having four header pipes terminating in outer ends arranged in two facing pairs with the axes of the outer ends of all four header pipes in a common plane and with the outer ends of the header pipes of one pair in alignment with the outer ends of the respective header pipes of the other pair, the combination of:

(a) a one-piece body provided therein with four inlet openings respectively adapted to receive therein the outer ends of the header pipes;

(b) said inlet openings having their axes in a common plane and being arranged in two pairs which face outwardly away from each other;

(c) said inlet openings of one of said pairs being in alignment with the respective inlet openings of the other of said pairs;

(d) said body further being provided therein with a single outlet opening having its axis perpendicular to said common plane of the axes of said inlet openmgs;

(e) said outlet opening being centrally located with respect to said inlet openings so that said inlet openings are symmetrically arranged about the axis of said. outlet opening;

(f) said body being provided therein with passages respectively connecting said inlet openings to said single outlet opening; and

(g) said passages including curved walls providing for smooth flow of exhaust gases from said inlet openings to said single outlet opening.

2. An exhaust collector according to claim 1 wherein said body is provided at the inner ends of said inlet openings with outwardly facing shoulders against which the outer ends of the header pipes are abuttable.

References Cited UNITED STATES PATENTS MARK M. NEWMAN, Primary Examiner D. HART, Assistant Examiner

Images