US2836160A - Carbureting means - Google Patents

Description

May 27, 1958 c. L. AKERS.

cmunmms was Filed Feb. 28. 1955 iii INVENTOR C ILA 7C e rs ATTORNEY.

United States Patent F CARBURETING MEANS Cecil Lynn Akers, Anderson, Ind. Application February 28, 1955, Serial No.-490,861

2 Claims. 01. 12s 117 This invention is designed to provide a new and improved carbureting means for improving the efliciency of internal combustion engines and decreasing fuel consumption.

A further object is to obtain the desired results by an improved application of the Venturi tube principle.

Another object is to provide a novel construction which will produce a better mixture of fuel and air with out the use of delicate and elaborate mechanisms.

With the above and other objects in view that will become apparent as the nature of the invention is better understood, the same consists in the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawing, and particularly claimed.

In the accompanying drawing, the figure is a vertical sectional view partly broken away and partly in elevation, showing the invention.

The construction shown in the drawing will be rather specifically described but it is to be understood that variations may be made without departing from the spirit and scope of the invention as claimed.

A vertically elongated carbureter body 1 is provided, said body having an air horn 2 at its upper end forconnection with an air cleaner, and having a mounting flange 3 at its lower end. The flange 3 is shown secured by cap screws 4 upon a heat insulator 5 which lies upon a carbureter-mounting boss 6 of an intake manifold 7.

A straight air admitting and mixture conducting passage 8 extends from the upper to the lower end of the body 1 and communicates at its lower end with a passage 9 in the boss 6 of the mainfold. In the upper or anterior portion of the passage 8, a conventional choke valve 10 is mounted; in the lower or posterior end portion of this passage a suitable throttle valve 11 is provided; and between the two valves 10 and 11, an auxiliary Venturi 12 and depending skirt 12a are mounted on spider arms or the like 13. The main discharge jet 14 from the fuel bowl 15 extends into the auxiliary Venturi 12. Fuel for idling is admitted through conventional ports 16 and 17, one of which is controlled as usual by a needle valve 18.

The small opening 19 to the left of the throttle valve 11, is a so-called vacuum spark hole, and the tube 20 is the conventional tube to extend to customary vacuumand spring-actuated spark advancing and retarding means of a conventional ignition distributer.

From the upper end of the horn 2 to a plane 21 near the lower end of the auxiliary Venturi 12, the passage 8 is cylindrical. From the plane 21 to a plane 22 at or near the lower end of the skirt 12 the passage 8 is conically contracted as seen at 23. From the plane 22, the passage 8 is downwardly flared conically at 24, to a plane near the upper region of throttle valve movement. The flare 24 is preferably at approximately 6.

From the plane 25 to a plane 26 near the lower region of throttle valve movement, the passage 8 is again cylindrical as seen at 27; and from said plane 26 to the lower extremity 28 of the body 1, said passage is again downice wardly flared conically as at 29. The passage 9 in the boss 6 is also downwardly flared at the same angle as the flare 29 and constitutes an uninterrupted continuation of the passage 8.

The passages 89 form what may be termed a main Venturi tube having its throat at the plane 22. The distance from this throat to the lower extremity 9 of the passage 9, is approximately four and one-half to six and one-half times the diameter of the Venturi throat (plane 22).

The following results are obtained:

The flow through the main Venturi neck (at plane 22) is more and the static pressure in the throttle chamber 27 is less than in the conventional construction where the throttle is not set in the zone of the downstream flare of the Venturi, but is set normally beyond it.

This lower static pressure in the cylindrical throttle chamber 27 will tend to break up the particles of fuel more completely. This breaking up of the fuel particles will permit more oxygen to be made available for uniting with more particles of fuel.

This complete communication of the fuel and oxygen will produce a more eflicient air-fuel mixture.

This more efficient air-fuel mixture will also favor a more complete vaporization of the fuel.

This vaporization will lower the air-fuel mixture temperature. Thus inducing a further drop in pressure even in the throttle chamber, and this increased vaporization with cooling of the air-fuel mixture will cause the equivalent of a supercharging effect at full throttle.

At full throttle the horsepower of an engine will be increased.

At full throttle the torque of an engine will be increased.

At full throttle the acceleration of an engine will be increased.

At full throttle, due to the supercharging efiect, the intake mainfold vacuum will lessen to approaching atmosphere pressure; which will reduce the horsepower required during pumping cycle.

At full throttle with better air-fuel mixture and fuel vaporization better fuel distribution will be had.

At full throttle more fuel economy will result in terms of less pounds of fuel per horsepower hour.

At full throttle the overall temperature will be lower due to less residual heat caused by less unburned fuel in the exhaust system.

At full throttle longer spark plug life will result, due to less ignition voltage required to break down the spark gap with better fuel distribution and fuel-air mixture, which has a less deteriorating effect.

At full throttle and higher altitude an engine will perform better and cooler, due to the situation that as a carbureter ascends in altitude the atmosphere is found to decrease in pressure, temperature, and density. The weight of each air (oxygen) charge taken into the engine decreases with the decrease in air density, cutting down the power in about the same percentage. In addition, the mixture proportion delivered by the carbureter is affected, the mixture becoming richer, at a rate inversely proportional to the square root of change in air density. There is less fuel present to start with and therefore will not become so over-rich in terms of air density.

At part throttle with the complete communication of fuel and oxygen producing a more eflicient air-fuel mixture, less fuel will be needed and therefore the throttle can be closed more to accomplish the same work, thus increasing the manifold vacuum which is beneficial to the air-fuel mixture and overall distribution.

At part throttle the economy will be better in terms of miles per gallon of fuel.

At part throttle the increased manifold vacuum will produce moremotive power to actuate theignition disnibutor over the fullrange of operation where needed.

The acceleration of an engine will be better. It is true that a more eflicient air-fuel mixture is delivered to the combustion chamber, resulting inmore power being produced with less fuel. Therefore, the control throttle .of

the carbureter can beclosed to'a greater degree. Whenever the throttle is closed further, it elevates the suction manifold vacuum measured by inches of mercury. The voverall temperature will be, lower due to less residual heat caused by less unburned fuel in the exhaust system. Also, longer sparkplug life will result, due to less ignition voltage required to break down the spark gap with better fuel-air mixture, which has less deteriorating effect.

a ,At part throttle and higher altitude the engine-will perform better and cooler due to the situation that as. .a carbureter ascends in altitude the atmosphere is found to decrease in pressure, temperature and density. :The

'weight of each air (oxygen) charge taken into the engine decreases with the decrease in air density, cutting down the power in about the same percentage. In addition,

the mixture proportion delivered by the earbureter is affected, the mixturebecoming richer, at a rate inversely proportional to the square root of change in air density. There is-less fuel present to start with and therefore'will notbecome so over-rich in terms of air density.

At cold or hot cranking and idling thelengine will start and run better due to higher manifold'.vacuum,

better fuel-air mixture andless fuel required to do the work. Also made possible is the conservation of crude 4 petroleum by promoting more efficient utilization of .fuel in an engine.

From the foregoing, it will be se'en'that a novel and advantageous construction has been provided. However, attention is again invited to the possibility of making variations within the scope of the invention as claimed.

I claim:

1. In a down-draft carbureter for "supplying'a horizontal intake manifold with anefiicient fuel-air mixture, a substantially vertical conduit having a choke valve at its upper end, a Venturi below it, followed by a cylindrical throttle chamber, and a flaring passage extending/T V downwardly therefrom to said horizontal manifold the angle of flare being substantially the same as that of a the downstream portion of .said Venturi. a i

2. A combination as defined in claim 1, the major portion of said flaring passage being formed-in a boss on top of said intake manifold, to which the rest of said carburetor is attached. 7 a

References Cited in-the file of this; patent UNITED STATES PATENTS V V ;Balfe Mar. 9,; 1 937 'Bryant [Oct. 19, 1937 Moseley Sept. 9, 1941 .Phillips Oct; 20,1953

OTHER REFERENCES r Berrys Handbook of Chemical Engineering, 1st edition, 19-34, McGraw-Hill, New York, page 696.

Images