US1677429A - Internal-combustion engine - Google Patents

Description

July 17, 192 8.

D. COLE INTERNAL COMBUSTION ENGINE- Original Filed Sept. 9. 1918 Patented July 17, 1928.

UNITED STATES PATENT FFICE.

JJOlll' COLE, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO JOHN A. DIENNER, 0F

CHICAGO, ILLINOIS.

INTERN AL-COMIBUSTION ENGINE. I

Application filed September 9, 1918, Serial No. 253,141. Renewed .Tune 16, 1924.

invention relates to internal combustion engines. More particularly my invention relates to a method of and means for the.

promotion of better combustion in internal combustion engines.

The increase in the cost of gasoline has been the cause of numerous attempts to utilize the 'heavier and cheaper fuel oils for motive power. I am aware that these attempts have resulted in a number of methods by which heavier oil fuel such as kerosene, which is the most economical and conveniently obtained fuel for internal combustion engines, may be used in engines of conventional design. Practically all of these methods include attachments for heating the kerosene before or at the time of feeding it to the engine, the oil being heated to change it into a gaseous condition.

These methods have been generallyv unsatisfactory, due to the difficulty encountered in properly vaporizing the fuel and I have observed thatif the vaporous fuel comes in contact with too great a heat, it will be dis integrated, its hydrogen being freed and its carbon being deposited on the sides of the- -cylinder and on the piston head.

Attempts have heretofore been made to burn kerosene by heating the air to fairly high temperature prior to carburetion thereof. -The consequent expansion of the air materially reduces the efliciency of the engine.

As well understood by those skilled in the art, kerosene-and the heavier oils do not evaporate readily thereby making vaporization very diflicult.v The relative non-volatility of kerosene is the property that has proven to be the greatest stumbling block in its development as an oil fuel for internal combustion engines. 7

My invention aims to provide for the use of the cruder and cheaper fuel oils as a if the fuel is not finely atomized it will not have sufl'icient time for complete combustion and will settle on the walls of the cylinders and the piston head and there carbonize.

In accordance with the well known fact that the boiling point of a liquid falls with a decrease of pressure, I provide for feeding the fuel oil into a relatively high vacuum, air being admitted only after approximately the maximum vacuum has been reached. I have observed that upon feeding a fuel oil such as kerosene into a relatively high vacuum, it will be immediately vaporized, then upon admitting the necessary amount of air an even mixture and quick burning charge will be thereby secured.

In order that those skilled in the art may be fully. acquainted with the nature and scope of my invention, I shall describe a specific embodiment of-the invention in connection with the accompanying drawings which form a part of the present specification and in which Figure 1 shows in vertical cross section an illustrative embodiment of my invention;

Figure 2 is a vertical sectional view of the pump employed in connection with the embodiment shown in Figure 1;

Figure 3 is a typical indicator diagram taken from an engine constructed in accordance with myinventi on, and r Figure 4 is a modification wherein the stroke of the pump and the air inlet are independently controlled.

The engine shown in vertical section in Figure 1 is provided with the crankcase 1, in which the crank shaft 2 is mounted. Although there may be a plurality of cylinders, only one cylinder, 3, is shown, this cylinder having a piston 4 connected with the crank shaft 2 by means of the connecting rod 5. The cylinder 1 is cooled by means of the usual water jacket 6 surrounding the top and sides thereof.

Figure 1 shows the position of the piston 4 when compression is taking place, the valve in the fuel inlet passage .being inthe closed position and a charge of fuel oilin readiness for the next suction stroke. The

the engine in the ordinary manner. The ex- ;ha-ust valve 7 controls the valve port leading to the exhaust manifold 12, the inlet valve 6 controlling the air inlet passage 13. The valve stems 14 and 15 of the valves 6 and 7 respectively extend up through the upper wall of the cylinder 3 and are proable springs 18 and 19 are arranged about the valve stems 14 and 15 respectively, be-

tween the flanges 16 and. 17provided on these stems and the head of the cylinder 3.

These springs are of suflicient strength to normally hold the valves 6 and 7 upon their seats as shown in Figure 1, against the vacuum produced in the cylinder 3.

The upper ends of the valve operating rods 20 and 21, the lower ends of which co-' operate with the cams 10 and 11, are pivotallv connected to one of the free ends of the rocking levers 22 and 23. The opposite ends of the rocking levers 22 and 23 are pivotally iconnected to the upper ends of the valve stems 14 and 15, these rocking levers being pivotedfwithin their length at 24 and 25 respectively. It will now be apparent that cooperation of the cams 10and 11 with the lower ends of the valve operating rods 20 and 21 will lift these rods upwardly, thereby moving the valves 6 and 7, through the rocking levers 22 and 23, downwardly from their seats against the tension of the springs 18 and 19.

Fuel oil is supplied to the cylinder 3 of the engine from a reservoir 26 by way of the pipe 26 and the fuel inlet passage 27. I provide a valve 28 for controlling the flow of fuel oil through the inlet passage 27. The valve 28 is controlled by a valve rod 29, which co-operates with a cam 30 mounted upon a suitable cam shaft, this cam being timed-to open the valve 28 when a relatively reservoir 32 by means of a pump high vacuum has been created in the cylinder 3 during the suction stroke of the plston 4.

' The fuel tank 31 is connected to the reser voir 26 by means of a pipe 38, the fuel oil be ing periodically supplied from the tank 31 i0 33. s hereinbefore explained, during the running of the engine the cam shaft 8 is rotated, the cam 10 mounted there'upon'co-operating with the valve operating rod 20 at substantially the end of each suction stroke to open the air intake valve 6, and thereby admits air in quantity and in proportion to support the combustion. Further rotation of the cam shaft 8 causes the cam 10 to engage the stem 49 projecting inwardly from the plunger 37 of the pump 33, thereby moving the plunger 37 into the cylinder 39 of the pump against the tension of the spring 40. As the cam 10 continues to rotate the plunger 37 will be released, allowing the spring 40 to move the plunger 37 outwardly. Thus the fuel oil is drawn from the tank 31 during the suctionthe compression stroke of the pump. As the supply of fuel oil maintained in the reservoir 26 is just sufficient for one charge, it

will be apparent that the amount of oil drawn into the cylinder 3 during one suction stroke of the piston 4 is controlled by the stroke of the pump 33.

The air inlet passage13 which admits air to the cylinder'3 when the intake valve 6 is "opened, is suitably controlled as by a butterfly valve 43, which may be termed a throttle.

The form of my invention shown in Figure 1 is particularly adapted for marine purposes, in that the butterfly valve 43, which controls the quantity of 'air drawn into the cylinder 3 during the suction stroke of the piston 4 is controlled by a lever 44; this lever at the same time controlling the stroke of the pump 33 and consequently controlling thequantity of oil supplied from the tank 31 to the reser-. voir 26. The lever 44 controls the stroke of the'pump 33 through the links 45 whichare operably connected with ashaft 35; movement of the lever 44 rotating the shaft 35. A cam 34 is mounted upon the shaft '35 and is adapted to co-operate upon movement of the lever 44 with the flange 36 carried by the plunger 37 of the pump 33, to eitherincrease or decrease the outward movement of the plunger 37 accordingly as to whether the throttle 43 is opened or closed. A

It will now be apparent ing the'air inlet opening 13 by means of the lever 44 the amount of oil delivered to the reservoir 26 will be correspondingly in- 1 creased, thereby maintaining a substantially constant ratio between the oil and the air. This is desirable in a marine engine as the requirements of such an engine do not to any great extent; 7 4

In Figure 3]? have shown a typical indicator diagram ,takenvfrom an engine of my improved construction. As well understood by those skilled in the art, this diagram has ordinates which are proportional vary valves41 and 42 are provided in the 1 that upon increas- I to the pressures acting upon the enginezpiston at each point during its working and return stroke and abscissa proportional to the corresponding space moved through by the piston 40f the engine. The indicated horsepower is proportional to the positive area of the diagram thus obtained.

I will now describe with the aid ofthe i 1 indicator diagram shown in Figure 3, which the heat. From this point it wil I consider to be uniquein so far as indicator diagrams taken from internal combustion engines are concerned, the operation of the particular embodiment of my invention shown in Figure 1.

Assuming the piston 4 to be in its uppermost position upon starting the engine the, downward movement of the piston will trace the suction curve A upon the indicator card. The curve thus traced, which is obviously considerably lower than the suction curve taken from the usual internal combustion engine and may run as low as 8 or 10 pounds of suction shows that the piston 4 started from its uppermost position with a pressure of substantially 15 lbs. to the square inch acting thereupon, from where the suction curve A curve-s downwardly until the maximum vacuum within the cylinder 3 is reached at approximately the point B. The cam 30 is timed to engage the valve rod 29 at some point prior to the opening of the air valve 6, thereby opening the valve 28 and allowing the charge of fuel oil which was previously stored in the reservoir 32 by the pump 33, to be drawn into the relatively great vacuum existing in the cylinder 3. Upon releasing the charge of fuel oil into this relatively great vacuum the fuel will be very thoroughly atomized due tothe fact that the boiling point of a liquid falls with a decrease of pressure. Any of the liquid fuel coming in contact with the hot walls at once vaporizes due to the low ressure and l be seen that the suction curve A runs upwardly due to opening of the valve 6 by the cam 9, which is timed to engage the-valve operating rod 20, thereby moving the air inlet valve 6 downwardly from its seat through the rocking lever 23.' The necessary amount of air is then drawn into the cylinder 3 thru the air inlet passage 13, thereby forming an even mixture and quick burning charge, the suction curve-A rising substantially vertically upwardly from this point to approximately 15 lbs. to the square inch again, the pressure curve in the cylinder 3 then following in substantially a straight line although the pressure will decrease to a very slight extent until the end of the suction stroke is reached.

Compression then takes place above the piston 4 during its upward movement, the pressure within the cylinder 3 during this upward movement of the piston being shown approximately by the compression curve D of Figure 3. Upon completing the compression stroke the mixture within the cylinder 3 is ignited, the pressure increasing slightly and then decreasing during the expansion curve E of Figure 3. Upon completing the expansion or working stroke the cam 8 is timed to open the exhaust valve 7, the pressure within the cylinder 3 during the exhaust prior to the beginning of the compression stroke of the engine.

The cam 34 is so placed as toblock the outward movement of the flange 36 which flange is secured to the movable plunger 37. Thus by varying the projection of the cam the piston is permitted to travel outward to a greater or less degree as desired, thereby varying the effective stroke of the pump.

The spring 40 forces the plunger 37 outward, drawing a charge of liquid fuel into the cylinder 39 and engagement of the cam 10 with the stem 49 forces the plunger in ward, discharging the measured quantity of liquidfuel into the cup 26.

.Altho the particular embodiment of my invention described in connection with Figure 1 is especially adapted for marine purposes, wherein a substantially constant ratio between the oil and the air is desirable for a given engine speed, it is to be understood that my invention is equally applicable to engines wherein the requirements thereon vary as in the. case of automobile engines and the like. In this case the stroke of the pump 33 and the air inlet opening 13 may be controlled independently as shown in Figure 4. For this purpose I have provided a lever 47 for controlling the butterfly valve 43 independently of the pump 33, the position of the butterfly valve 43 determining the quantity of air drawn into the cylinder 3 duringthe suction stroke of the piston 4. An independent lever 48 is then provided for controlling the stroke of the pump 33 through the links 45 and cam 34. Thus when a rich mixture is desired, the stroke of the pump 33 is increased by means of the lever 48, the air inlet opening being decreased by means of the lever 47. When a leaner mixture is desired, the air inlet opening may be increased by means of the lever 47 and the stroke of the pump may be decreased by means of the lever 48, it being understood, of course, that the stroke of the pump 33 determines the quantity of fuel oil that is periodically stored in the reservoir 32, this entire quantity being drawn into the cylinder of the engine during the suction stroke thereof.

The fuel injector which I have shown is ,really no more than a fuel measuring device and is not a carburetor. While I have shown the fuel as admitted in a solid stream it is obvious that an air bleed might be provided for speeding the flow of the fuel or for breaking it up for easier vaporization as is shown in my co-pending application, Se-

any air which is admitted with the fuel is insuflicient to support combustion. It is desirable .to admit the fuel into as high a vacuum as possible and any air which is ad- I mitted. with the fuel tends to bleed or de stroy the vacuum.

Thecontrol devices which I have shown for varying the amount of fuel injected per stroke may be varied. I have found that the amount of fuel may be controlled at each stroke by the amount of air bleeding of the fuel oil or by restricting-the admission of air to the fuel in the m asuring chamber as is shown in my co-pend ing application, Serial Number 253,140 of even date, For the broader aspects of my invention any suitable means for controlling the'quantity of fuel introduced may be employed.

While I have described my invention in connection with the details of a particular embodiment, it is to be understood that this embodiment is merely illustrative and I do not intend thereby to limit the invention to such details, as I am" aware and contemplate that modifications and changes may be made without departing from the scope of the invention'which is set out in the appended claims.

I claim:

V1. The method of promoting combustion in an internal combustion en'ginewhich con-' sists in periodically supplying fuel from a source of supply to a reservoir of capacity suitable for one charge, creating a relatively high vacuum in the cylinder of the engine and then admitting the fuel substantially unmixed with air from said reservoir into said relatively high vacuum and admitting air at the end of the suction stroke only.

2. The method of promoting combustion in an internal combustion engine which consistsin creating a relatively high vacuum the cylinder of the engine, supplying a fixed charge of fuel and then admitting the fuel in a fixed charge into said cylinder only after a delayed interval suflicient to establish a relatively high vacuum therein, admitting air into the vacuum at the end of the suction inder.

stroke only, and comp'ressin I andfiring the I resulting mixture in said cy inder.

3. In an internal combustion eng ne, a

cylinder, a piston operating in said cylinder,

a crank shaft with which said piston is connected, inlet and exhaust valves for said cylinder, a fuel inlet passage for admitting fuel in a fixed charge to said cylinder substantially devoid of air only after a relatively high partial vacuum has been created in the cylinder, means for opening said air inlet valve only subsequent to the admission of fuel into said relatively high vacuum, means for controlling the-quantity of air admitted through said inlet valve and means for controlling the quantity of fuel forming said fixed charge. r

4. In combination, an internal combustion engine, an air inlet valve for said engine, a fuel reservoir suitable for one charge of liquid fuel, a fuel inlet. valvev for admitting liquid fuel from said rservoir to the cylinder of said engine subsequently to creating arelatively high vacuum in said cylinder,

means for replenishing said reservoir contmuously, and means for admitting airthrough said inlet valve only after the. admission of fuel in liquid form into saidirelatively high vacuum.

I 5. In an internal combustion engine, a combustion cylinder, a piston"therein, mechanically operated admission and exhaust valves'for said'cylinder, means for supply- 7, I

ing liquid fuel to the cylinder, a liquid fuel .valve, a main air valve for controlling the admission of air from atmosphere into' said cylinder, the timing of said valves being such that when the fuel valve is opened a relatively high vacuum in the cylinder is effective to draw the-liquid fuel into the cylinder and vaporize the same, the air valve being timed'to open at the end of the suction 'stroke only for admitting the required complement of air, and a throttle for controlling the volume of mixture in said cyl- 1 non COLE.

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