US2500409A

US2500409A - Means for maintaining constant compression in cylinders of internalcombustion engines

Info

Publication number: US2500409A
Application number: US599382A
Authority: US
Inventors: Hawkins Grover
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-06-14
Filing date: 1945-06-14
Publication date: 1950-03-14
Anticipated expiration: 1967-03-14

Description

March 14, 1950 G. HAWKINS MEANS FOR MAINTAINING CONSTANT COMPRESSION IN CYLINDERS OF INTERNAL-COMBUSTION ENGINES Filed June 14, 1945 Sheets-Sheet l 2.9 5 95" 3 V2; g x-25 2 E/ 6 Q Q 21 22 E '5 I9 P1 0 V 25 I0 9 Q;

Q; 2 I H i i INVENTOR.

GRcvER H w\ \MS A'ITD R N EYS 2 Sheets-Sheet 2 March 14, 1950 G. HAWKINS MEANS FOR MAINTAINING CONSTANT COMPRESSION IN CYLINDERS OF INTERNAL-COMBUSTION ENGINES Flled June 14, 1945 IN 1w TOR.

ATTD RN EYS Patented Marl 14,

MEANS FOR MAINTAINING CONSTANT COM- PRESSION IN CYLINDERS OF INTERNAL- COMBUSTION ENGINES Grover Hawk ins, Shoshoni, Wyo. Application June 14,1945, Serial No. 599,382

1 Claim. (Cl. 1 23-78) My present invention, in its broad aspect, has to do with improvements in means for maintaining a more or less constant compression in cylinders of internal combustion engines, and

, especially two and four cycle engines of the auto type, whereby tendency to knock .is reduced, greater efliciency obtained at low throttle, and greater torque at fullthrottle, and whereby a very small residue of burned gases remain in a cylinder at the beginning of the intake stroke, hence a lower temperature is maintained on compression and a considerable saving efiected in fuel consumed. v

In accomplishing the above and other results and advantages, I provide a pressure equalizing chamber communicating through a conduit and valve with the cylinder of the engine, and also communicating through a port with a cylinder having a pressure responsive free piston, and which cylinder also communicates with the cylinder of the engine, so that changes in compression (rise and fall of pressure) in the cylinder of the engine influence the movement of the free piston to regulate both th compression in the cylinder of the engine and in the pressure equalizing chamber, and open and close the port between the pressure equalizing chamber and the cylinder of the pressure responsive free piston.

Other and equally important objects and advantages of my invention will be apparent from the following description and drawings, and it is pointed out that changes in form, size, shape, materials, and construction and arrangement of parts are permissible and within the purview of my broad inventive concept, and the scope of the appended claim.

In the drawings, wherein I have illustrated a preferred form of my invention:

Figure 1 is a vertical section through my invention;

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

Figure 3 is a section on the line 3-3 of Figure 2, and

Figure 4 is an enlarged vertical sectional view of the valve shown in Figure 1.

In the drawings, wherein like characters of reference are used to designate like or similar parts:

The numeral l designates the cylinder of a conventional internal combustion engine, and 2 the piston. The head 3 of the cylinder is modified in accordance with my invention and has water circulation channels 4 for cooling intake and exhaust valves 5 and 5A, and a spark plug Bsee Figures 2 and 3. The head 3 carries a small cylinder 1 communicating through the restricted open base 8 with the main cylinder l-such restricted base forming an annular shoulder 9 which has a spring valve ID to cover the ports 9a opening into the cylinder I. The use of the ports will make the total area of the piston l1 effective rather than just thehead l9, and a head II. The head II is flanged, as at I2, for attachment to the flange M at the tcp of the cylinder, and is formed with a depending dome shaped extension I5 within the cylinder and hav-- ing a rounded end It. A free piston I I having a skirt l8 and a head (9 is mounted for movement in the cylinder I, and the head is provided with an extension fitting in the restricted base 8. The trapped air between the head and skirt portions of piston l1 and the extension l5 and head I l cushions the upward stroke of the piston, and trapped air between the shoulder 9 and head l9 cushions the downward stroke oi the piston.

At a point near the limit of the upward stroke of the piston H, the cylinder 1 is provided with a port 20 communicating with a pressure equalizing tank or chamber 2 I, which also communicates through a conduit 22 with the top of cylinder i; there is an adjustable valve 23 interpolated in the conduit 22. The valve 23 is of the automatic type, and has a cylinder 24 and a piston 25, a connection 26 leads gases under pressure from the main cylinder I and has branches 26A at opposite points of the piston 25. Movement of the piston is responsive to pressure beneath it so that gas is transmitted to the compression chamber until a predetermined pressure is reached, whereupon the piston 25 moves to close the connection 26A against the pressure of spring 2! which is adjusted by thescrew 28 and cup 29 against which the spring 21 bears. In operation when starting the engine cold, there would be no pressure in tank 2i, so at the first compression stroke, free piston ll would be forced up to the top of its cylinder, and would stay there. Thus the engine would function as a conventional gas engine.

.With no pressure in 2i and conduit 22, valve 25 would rest at the bottom of its cylinder under pressure of spring 21, and ports 26a would be open into the annular space in the valve 25 and by the ports therein to the under side of valve 25, directly through conduit 22 to tank 2|.

At the compression stroke, a small amount of air will pass through, and after the explosion, more of the now burned gases will rush through. After a few minutes running, the desired pres- 3 sure as regulated by adjusting screw 28 will be reached in 2|, at this point valve 25 will have reached the closed position shown, cutting ofl ports 26:: and preventing further admission 01' air or gas. It pressure falls in 2| and 22, spring 21 will push valve 25 down, admitting more gases, thus maintaining a constant pressure in tank 2|.

Hence, as piston 2 comes up on compression. free piston I! will not begin to rise until pressure above piston 2 is a little above that in 2|.

Thus, as the piston 2 comes up on the compression stroke, the piston |1 rises until the pressure above the piston I! is a little above the pressure in tank in chamber 2|, and by reason of valve 23 pressures will also rise in tank or chamber 2| until all pressures are substantially equalized. Upon the firing of cylinder I, piston I! will be driven higher in cylinder 1 to close port 20. As piston 2 descends on the power stroke, pressure in cylinder falls below that in tank 2|, and piston |1 descends maintaininga substantially constant pressure in cylinder until it reaches the bottom of its stroke.

The depending dome of the head of cylinder 1 is so designed to fit snugly down in free piston H, thus reducing clearance, and increasing the cushionin efiect. With a fiat head, the skirts of H would hammer against it. When the engine is throttled, piston |1 will only rise part way up in its cylinder; when the: explosion occurs, it will be driven up with considerable force, and so this piston must be cushioned as described.

From the foregoing it is believed that the operation and advantages of my invention will be apparent, but it is again emphasized that interpretation of its scope should only be conclusive when made in the light of the subloined claim.

I claim:

Means for maintaining a constant compression in a cylinder of an internal combustion engine, comprising a pressure equalizing tank having an adjustable valved communication with the cylinder to receive gases therefrom to a predeter- 4 mined pressure in the tank, said adjustable valved communication including a. conduit, a valve having a pressure responsive piston controlling passage of gases through the valve, a spring against which the valve operates and means for adjusting the tension of the spring on the valve, a cylinder communicating with the cylinder of the engine and having a port communicating with the pressure tank, a free piston in the cylinder responsive to pressures in the tank and the engine cylinder, and opening and closing the port at points in its stroke whereby to be moved down by pressure in the tank and moved up by pressure in the engine cylinder, said free pressure responsive piston having a head and a skirt, the skirt opening and closing the port, and the cylinder of the free piston having a head with a depending dome between which and the piston air is trapped to cushion the upward stroke of the piston and air annular shoulder at the lower end of the cylinder between which and the piston air is trapped to cushion the downward stroke of the piston relatively spaced ports in said shoulder and a spring valve adapted to control the ports to balance the piston during downward stroke thereof.

GROVER HAWKINS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,415,025 Folsom May 9, 1922 1,817,747 Hartley Aug. 4, 1931 FOREIGN PATENTS Number Country Date 4,281 France Nov. 30, 1905 467,960 France June 25, 1914 176,233 Great Britain Mar. 9, 1922 557,969 France Aug. 20, 1923