US2117983A

US2117983A - Internal combustion engine

Info

Publication number: US2117983A
Application number: US52224A
Authority: US
Inventors: Elliott G Reid
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-11-29
Filing date: 1935-11-29
Publication date: 1938-05-17
Anticipated expiration: 1955-05-17

Description

May 17, 1938. E. G. REID I 2,117,983

I INTERNAL COMBUSTION ENGINE Filed Nov. 29, 1935 III, I, II'III/ I Z5 5/ L23 3/ 49 ,,IIIIIIIIIIII j llllll llll Patented May 17, 1938 UNITED STATES PATENT OFFICE 13 Claims.

The present invention relates to internal combustion engines and particularly to intake manifolds for engines of this class.

As is well-known, the present tendency of builders of internal combustion engines is to design and construct such engines with relatively numerous cylinders with the end in view of realizing the advantage of greater uniformity of power delivery for a given combined cylinder volume, and to obtain other recognized advantages. Especially where such an engine is to be employed as a means for supplying power for propelling an automotive vehicle is it appreciated that an engine having a considerable number of cylinders has advantages over those employing relatively few cylinders. Numerous automobile engines now in use have eight cylinders, and some have more. It is also desirable to make use of only ane carburetor or fuel and air mixing device and to provide what is designated an inlet or intake manifold by means of which such single carburetor is connected to all of thegcylinders of the engines for the purpose of supplying each cylinder with the requisite amount of fuel. Naturally, the several pistons being connected to a common crank shaft, the power developed in each cylinder by the ignition of any explosive charge introduced should be equal in magnitude to the power developed in each of the other cylinders in subsequent explosions as otherwise nonuniformity of operation of the engine would result.

The problem of supplying all cylinders of a multi-cylinder internal combustion engine with equal charges of fuel from a common carburetor has, however, not been an easy one to exactly solve and, while many attempts to bring about this desirable result have heretofore been made, no entirely satisfactory, solution has been 40 reached. Thus it is found that, notwithstanding all precautions which it has heretofore been considered possible to take, certain of the cylinders of an engine are frequently supplied with charges which do not have the same power values upon explosion or ignition as have the charges supplied to other cylinders. It will be appreciated that each cylinder is only intermittently charged and that the piston therein is only intermittently driven upon its working stroke by expansion of the ignited charge. In other words, by reason of the action of the inlet valve of such cylinder, the flow of combustible mixture thereto is intermittently initiated and halted. This intermittent starting and stopping of the flow of combustible charge results in what are designated manifold pressure waves, surges, or oscillations, which travel backwardly from the inlet valves toward the carburetor and which tend to destroy the uniformity of the fuel and air mixing action of the carburetor by varying the velocity of the air flowing through the carburetor throat. It has previously been suggested that these variations of Velocity at the carburetor throat may be minimized by the insertion, intermediate the carburetor and the conduits which lead to the engine cylinders, 'of means for damping the oscillations mentioned and thus preventing such oscillations from modifying the action of the carburetor.

The present invention contemplates the provision of an improved means of this character the primary purpose of which is to totally eliminate, or at least to so reduce as to render unimportant, the surges or pressure waves previously referred to and which have heretofore so greatly 0 disturbed carburetion. This I accomplish by designing the intake manifold so that it has intermediate the carburetor and the several con duits which lead to the cylinders of the engine,

a chamber in which'a substantial body of the 25 fuel and gas mixture is temporarily confined on its way to the engine, this chamber being so designed and constructed that the temporarily confined body of gas is caused to circulate rapidly along or around a closed or endless path. This U arrangement interposes between the carburetor and the engine cylinders what may be called a gaseous fly-wheel which, like its mechanical analogue, continues to rotate at a substantially constant angular velocity despite the application of fluctuating accelerating and retarding impulses. Thus the pressure waves originating at the valves are transformed into unimportantly small variations of the velocity of the gaseous fly-wheel and a practically steady, unidirectional flow through the carburetor is maintained. The net result is increased efficiency of operation of the carburetor and more equal distribution of the combustible charges to the several cylinders.

Likewise the Volumetric efficiency of an internal combustion engine with which the improved manifold is used is considerably increased. The charges flowing to the several cylinders are withdrawn tangentially from the whirling or rotating body of the fuel and air mixture instead of being drawn from a body of such mixture which may be stagnant, or even surging away from the cylinder, at that instant. Superior velocities of flow into the several cylinders, respectively, of the gaseous fuel mixture are therefore realized.

The specific means for accomplishing the objects of the invention may be varied somewhat in accordance with the fuel used, the number of cylinders of the engine and other factors, but in each instance a chamber will be provided intermediate the carburetor cr gas and air mixing device and the cylinders within which may be temporarily trapped a body of the fuel and air mixciably less than the volume of any single cylinder to which it is connected. It is best tointroduce the mixture through spiral passages which open into the toroidal chamber through ports in its inner wall and the discharge ends of the passages should be uniformly inclined in the same direction so as to deliver streams of mixture as nearly tangentially into the chamber as is possible; thus unidirectional motion of the entrapped gas is created with the minimum loss of energy. Gas is withdrawn from the toroidal chamber through two or more apertures formed in the outer wall of the chamberat equally spaced intervals and immediately passes into tangentially arranged conduits. These conduits communicate with branch ducts or conduits connected to the several cylinders.

An embodiment of the invention selected for disclosure by way of example is illustrated in the accompanying drawing, in which Figure 1 is a rather diagrammatic view showing in plan a multi-cylinder internal combustion engine to which the invention has been applied;

Figure 2 is a section on line 22 of Figure 1;

Figure 3 is a section on line 3-3 of Figure 2; Figure 4 is a section on line 4-4 of Figure 1;

and

Figure 5 is a partial section on the line 5-5 of Figure l.

The cylinder block of the engine diagrammatically shown in Figure l is illustrated at IE3. No details of the engine proper are shown but it will be understood that the engine may be of any type or design which includes inlet valves controlling the fiow of the fuel and air mixture through suitable passages into the several cylinders, respectively. The engine illustrated is pro vided with eight cylinders and. the axes of these cylinders are disposed in a common plane. It will be understood, however, that the invention is applicable to engines with all other cylinder arrangements as well as to engines of the in line type. In this case, the cylinders are arranged in groups of two for fuel feeding purposes, the outermost groups being supplied with combustible charges through conduits H and i2 and the innermost groups through conduits l3 and M. The inlet ends of conduits l! and i2 communicate re" spectively with a chamber and the inlet ends of conduits I3 and I4 are in communication with a second chamber I8, closely adjacent chamber I5 but not communicating therewith. The toroidal gas chamber is indicated generally at El and the outer wall of this chamber is provided with apertures to permit the outflow of mixture into tangentially arranged ducts or conduits l8 and I9, respectively. Tangential duct l8 communicates with the downwardly and inwardly turned manifold pipe and duct 59 communicates with the downwardly and inwardly turned manifold pipe 25, the outlet ends of these pipes communicating with chambers l5 and [6, respectively, previously described.

A portion of a carburetor is indicated at 25, this carburetor being positioned above and coaxially with the toroidal chamber I? and being of the down-draft type. It will be understood, however, that the invention may be used with full success with carburetors other than those of the down-draft type. The outlet port 26 of the carburetor is in register with a central similarly shaped aperture formed in a flange-like element 2'! and the gaseous mixture flowing downwardly through the carburetor port 2i? is transmitted to the toroidal chamber through a passage which brings this port into communication with all parts of the chamber, 1. e., the passage is brought into communication with a continuous aperture or slot 28 formed in what maybe designated the inner wall of chamber l'i.

The passage just briefly referred to is defined by the generally conical lower wall 29 and the frusto conical upper wall 30, these walls being preferably formed integrally with the walls 5'! of the toroidal chamber since the entire unit, including the ducts ifl, if), 29 and 2i may conveniently comprise a single casting, thus simplifying construction and installation. As shown in Figures 2 and 4, the walls 29 and 3G converge as they approach the circular port 23 so that the passage is constantly reduced in vertical section as it expands circumferentially. The convergence of the walls 29 and is such as to maintain the cross-sectional area of the passage leading to the chamber ill at an approximately constant value at all radii; the specific form of the passage will depend upon the actual dimensions and velocities involved in its design but the objective of such convergence shall be the reduction of re sistance arising from skin friction and discontinuous flow.

In order that the downfiowing fuel and air mixture moving toward the toroidal chamber shall be directed so as to cause the body of mixture within that chamber to be in a state of rapid rotation about the axis of the toroid, a plurality of curved vanes 3! are provided which vanes, in

, effect, divide the downfiowing stream of fuel mixture into a plurality of individual streams, all of which are discharged into the toroidal chamber in substantially tangential directions.

The carburetor employed may be of any desired type provided it efliciently mixes the liquid fuel with the air passing therethrough and it may be supported entirely by the unit including the toroidal chamber. In fact, the chamber 11 and its associated inlet and outlet passages may be formed as a unit suitable for ready application to existing types of internal combustion engines, this unit being merely inserted between the carburetor device and the several conduits which lead to the engine cylinders. V

The fiow of the fuel and air mixture through the several passages just described is of course brought about by operation of the engine, such operation causing the necessary suction. The fuel and air mixture delivered by the carburetor passes at high velocity into the toroidal chamber ll, the vanes 3| dividing the gaseous stream into smaller streams and directing these smaller streams into this chamber in such manner that the body of mixture therein is causedto circulate rapidly about the axis of the toroid. The mix- 'ture makes its escape from the chamber through tor is therefore not influenced by valve closures and the carburetion of the liquid fuel proceeds uniformly at all times. The withdrawal of the fuel mixture tangentially from the toroidal chamber, and at higher than customary velocity, facilitates introduction of the fuel mixture into the several cylinders and generally increases the volumetric efiiciency of the engine. In order that the maximum eificiency of the invention may be realized, care should be taken that no single conduit leading from the toroidal chamber to the engine should communicate with cylinders the inlet valves of which are simultaneously open.

While I prefer that the toroidal chamber shall be circular in cross-section, because this minimizes loss in velocity due to friction between the fuel mixture and the walls of the chamber, the exact cross-sectional shape of the chamber may be varied if desired for other reasons and the design and arrangement of the component elements of the invention may be otherwise modified so long as a body of continuously circulating fuel and air mixture is maintained intermediate the carburetor and engine to accomplish the specified functions.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising a toroidal chamber adapted to receive a mixture of fuel and air and to guide the same along a closed unrestricted path, means for delivering a fuel-air mixture into said chamber in a direction to cause movement of the mixture along said path, and conduits for leading streams of said mixture from said chamber to the engine cylinders.

2. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising an elongated chamber of substantially constant cross-section for guiding a fuelair mixture along a closed unrestricted path, the volume of said chamber being not substantially less than the Volume of one cylinder of the engine, means for delivering a fuel-air mixture into said chamber in a direction to cause movement of such mixture along said path, and conduits for leading streams of said mixture from said chamber to the engine cylinders.

3. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising an elongated chamber of substantially constant cross-section for guiding a fuel-air mixture along an endless path, stationary gas guiding means for directing into said chamber in directions substantially tangential to the chamber, a plurality of streams of fuel-air mixture to create a revolving body of such mixture, and conduits for leading streams of said mixture from said chamber to the engine cylinders.

4. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising a toroidal chamber, adapted to receive a mixture of fuel and air and to guide the same along an endless path, means for delivering a fuel-air mixture into said chamber in a direction to cause movement of the mixture along said path, and conduits for leading streams of saidmixture from said chamber to the engine cylinders, the inlet ends of said conduits being disposed in the'plane of said chamber and extending outwardly from said chamber in directions substantially tangential to the said chamber.

5. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising a toroidal chamber adapted to receive a mixtureof fuel and air and to guide the same along an endless path, means forintroducing into said chamber, at the innerside thereof, a plurality of streams of fuel and air mixture in directions substantially tangential to the said chamber, and conduits for leading streams of the mixture from the said chamber to the engine cylinders, the inlet ends of said conduits communicating with the interior of the chamber through apertures formed in the other side of the chamber wall.

6. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising a toroidal chamber adapted to receive a mixture of fuel and air and to guide the same along an endless path, means for introducing into said chamber, at the inner side thereof, a plurality of streams of fuel and air mixture in directions substantially tangential to the said chamber, and conduits for leading streams of the mixture from the said chamber to the engine cylinders, said conduits having the portions thereof adjacent said chamber disposed tangentially thereto in the plane of the chamber, and. extending outwardly therefrom.

.7. The combination with a multi-cylinder internal combustion engine, of an inlet manifold comprising a toroidal chamber adapted to receive a mixture of fuel and air and to guide the same along an endless path, means for delivering outwardly into said chamber a substantially tangentially directed stream of such mixture through an aperture formed in the inner wall thereof, apertures in the outer wall of the chamber through which streams of such mixture may be tangentially withdrawn, and conduits for leading said streams to groups of engine cylinders, respectively.

8. An inlet manifold for an internal combustion engine comprising a plurality of conduits for leading streams of fuel and air mixture to groups of cylinders, respectively, and means for supplying all of such conduits simultaneously from a common body of mixture which moves continuously and unrestrictedly along a closed path within a toroidal chamber.

9. An inlet manifold for multi-cylinder internal combustion engines comprising, in combination, a toroidal chamber for the circulation of a mixture of fuel and air, stationary means having spirally formed passages for introducing such a mixture into said chamber, the inflowing streams being similarly directed by said means, and a plurality of outlet passages for withdrawing mixture from the chamber, said passages being disposed tangentially to the toroidal chamber so as to permit the ready entry of gases thereinto.

10. An inlet manifold for multi-cylinder internal combustion engines comprising a toroidal chamber, stationary spirally arranged ducts having their outer ends opening into said chamber, said ducts being disposed substantially in the plane of the toroidal chamber, a passage for leading mixture simultaneously to all ducts, and a plurality of discharge apertures in the outer wall of the toroid.

11. The combination with a multi-cylinder internal combustion engine of an inlet manifold comprising a chamber shaped to guide a fuelair mixture along a closed path, stationary means for delivering a fuel-air mixture into said chamher in a direction to cause movement of the mixture along said path, said means being designed to insure that the velocity of the infiowing stream is approximately the same at all points, and conduits for leading streams of said mixture from said chamber to the engine cylinders.

12. The combination set forth in claim 11 in which the said means comprises a conduit defined by two mutually facing conical surfaces coaxially disposed, said surfaces converging outwardly from the axis toward the chamber.

13. The combination with a multi-cylinder internal combustion engine, of an inlet manifold comprising an elongated chamber of substantially constant cross-section for guiding a stream of fuel and air mixture along a closed 10 path, stationary guide means for directing a moving stream of fuel and air mixture into said chamber in a direction to cause movement of the mixture along said closed path,-and separate conduits for leading streams of said mixture from said chamber to the engine cylinders.

ELLIOI'I G. REID.