US2217942A - Auxiliary air inlet for internal combustion engines - Google Patents

Description

R. CAIRNS 311 ERNAL COMBUSTION ENGINES Oct. 15, 1940.

AUXILIARY AIR INLET FOR INT Filed Dec. 15, 1938 Patented Oct. 15, 1940 UNITED STATES PATENT OFFICE AUXILIARY 'AIR INLET FOR INTERNAL COMBUSTION ENGINES The principal ob jects of this invention are to effect a material increase in the efficiency of internal combustion 'engines by creating better combustion, reducing oil Consumption, increasing gasoline mileage and to gene'rally efiect a better performance.

The principal feature of the invention consists in the nove arrangement of an auxiliary air intake valve in an engine cylinder whereby greater turbulence of the explosive gases in the engine cylinder is achieved and stagnant pockets in the cylinder are obviated so that better ignition and flame propagation is effected, the intake being directed downwardly into the cylinder at a point opposite to the infiow of gas from the intake valve.

In the acoompanying drawing,

Figure 1 is a seotional elevational viewof an engine cylinder showing the piston in the uppermost position and illustrating the location of my improved auxiliary air intake valve.

Figure 2 is a sectional View similar to Figure 1 showing the engine piston moved downwardly with the intake and auxiliary valves open and illustrating the manner of flow of the gases.

Figure 3 is an enlarged elevational view of my improved valve.

Figure 4 is an enlarged longitudinal sectional detail of my improved valve.

It is commonly known among engineers conversant with the operation of internal combustion engines that the percentage of power units present in the regulation motor fuels is only partly converted into useful power. Numerous proposals have been made to provide engine cylinders with fuel intake valves and separate air intakes, but the present invention proposes a novel construction and arrangement .which has produced exceptional results.

In the Construction herein shown the cylinder l in which a piston 2 operates is closed by a head 3, which is preferably of the "Ricardo" type, directs the combustible mixture past the intake valve 4 across the top end of the pisten so that the stream of combustible gas flows in under the head to the side of the piston farthest from the intake.

An opening 5 is preferably arranged to extend vertically through the head 3 at the side of the cylinder farthest from the intake passage leading from the intake valve, and in this opening is arranged a valve body- 6 which is threaded externally to fit into the threaded wall of the opening, and has a central vertical passage 'I extending upwardly from the bottom end and communicating with a cross passage 8 which extends out through the side wall of the valve body.

The inner end of ,the vertical passage 'I is formed with a valve seat 9. A valve o of conical formation is adaped to engage and seal against the valve seat 9 and has a stem l l extend ing upwardly through the top of the valve body and the upper end !2 thereof is threaded and has arranged thereon an adjusting nut l3 and` a lock nut M.

A spiral compression spring l5 encircles the valve stern and engaging the nut at the top thereof, holds the valve against its seat. These nuts may be adjusted to vary the tension of the spring so that the valve will open upon a predetermined vacuum condition within the cylinder,

and'upon opening a stream of air will flow in through the passages 8 and] and ibe projected downwardly into the cylinder. The stream of air thus projected downwardly will meet with a p stream of combustible gas flowing across the inner end of the top of the cylinder following the downward movement of the piston, and mingling with this stream of gas, it will augment the flow thereof and greatly magnify the turbulence of the inflowing mixture, thereby preventing the stagnation of the products of combustion of a previous charge or of the fresh charge of combustible gas.

By arranging this automatic intake valve in' the position described it assists materially in scavenging the cylinder of burnt gases and as stated, greatly increases the turbulence, and it also increases the Volume of combustible mixture.

in the cylinder which is necessarily restricted by the ordinary intake valve in its Very brief and rapid period of movement.

In Figure 1 the valve body is shown directly threaded into the opening in the cylinder head and in Figures 3 and 4 the valve has threaded on its lower threaded end an adapter IB which is merely a threaded plug to be Secured in the threaded opening of the oylinder head, the valve being threaded into the interior of the adapter.

Very extensive tests have been made of this device over a period of approximately two years and a mileage of approximately twenty-four thousand mi1es, and it has been ascertained that a very material reduction in' the consumption of motor fuel is effected. Further it is found that the use of the device creates a very marked reduction in the consumption of lubricating oil.

It is also found that with the use of suchan auxiliary air inlet to the cylinders a much more accentuated braking eflect through the medium of the engine may be obtained and a smooth powerful braking action is efiected due to the valve taking in air When the throttle is closed.

When the engine is used in this manner it will be apparent that the combustion space will be effectively scavenged of burnt gases and cooled. This also eects a Very marked increase in acceleration when the throttle is again opened.

It will be read'ly apparent that having these valves in the cylinder to relieve the suction eiect when the throttle is closed and the engine is idling or Operating at slow speed in traffic, a. great saving in uel is effected.

A further advantage found in the use of this device is the absence of a smoky and odorous exhaust.

It will be readily understood that this inven tion may be applied to engines which are at present in use as well as to new engines as great economy and better performance will be obtained.

It will be noted that the valve body adaptor IS has a valve chamber 16' which converges downwardly to a passage I 6", the cross section of which is accurately proportioned in relation to the piston displacement and in the'event of the tension of the spring !5 being too` Weak as for instance through faulty adjustment or fatigue, the restricted orifice will guard against an excessive Volume of air being drawn into the cylinder.

Further should, for any reason, the valve become detached from the supporting spring, the

constriction of the valve chamber will prevent same from falling into the cylinder to cause damage.

What I claim as my invention is:

1. In an internal combustion engine having a cylinder and a fuel intake valve at one side of the cylinder and a spring-loaded valve for admitting air to said cylinder on the suction stroke of.` the piston, the combination being characterized in that the air valve inlet is positioned on the side of the cylinder farthest from the side on which the said fuel intake valve is located to direct the incoming air downwardly along the said farthest side of the cylinder and thereby enhanc'e-turbulence of the incoming fuel charge and minimize pocketing thereof.

2. An internal .combuston engine as claimed in claim 1 in which the engine is provided with a "Ricardo" type head forming with the head of the piston a chamber of progressively decreasing depth 'from the fuel inlet valve to the point of location of the said air inlet valve.

3. An internal combustion engine having in combination a vertical opening through the head arranged adjacent to the inner cylinder wall at the side of the cylinder farthest from the intake leading from the carburetor, a valve body threaded into the upper end of said vertical opening having a discharge passage arranged to concentratea stream of air in a. downward direction alongthe side of the cylinder farthest from the fuel intake,` and valve means controlling the flow of air through said discharge passage.

ROBERT CAIRNS.

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