US997195A - Two-cycle gas-engine. - Google Patents

Description

G. P. JENKINS. TWO-CYCLE GAS ENGINE. APPLICATION FILED 1107.18, 1910.

Patented July 4, 1911.

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C. P. JENKINS. TWO-CYCLE GAS ENGINE. APPLICATION FILED NOV. 18, 1910 Patented July 4, 1911.

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7 ////////////6V/ 5 /////////g w -1 III WITNESSES:

CHARLES FRANCIS JENKINS, OF WASHINGTON, DISTRICT OF COLUMBIA.

TWO-CYCLE GAS ENGINE.

pecsflcation of Letters Patent.

Patented July 4:, 1911.

Application filed November 18, 1910. Serial No. 593,028.

I To all whom it may concern:

Be it known that I, CHARLES FRANCIS JENKINS, citizen of the United States, residing at Washington, District of. Columbia, have invented certain new and useful Improvements in Two-Cycle'Gas-Engines, of

. which thefollowing is a specification.

This invention relates to that class of gas engines known as two-cycle engines.

It has for its object an engine which can be throttled down until it turns over slowly and explodes evenly under light loadiand when running idle. This is accomplished by placing the sparkingdevice at the point where the gas enters the combustion space-.

The two-cycle motor is notoriously waste,-

ful of gasolene in automobile use' on the comparisons of the two-cycle with four-cycle average road surface. This comes about not because the motor 1s not as efficient at hard work as. the four-cycle motor, but principally because, unless the motor is working atnear its maximum capacity, there is too large a proportion of the carhureted charge mixed with the burned gas of the previous explosion. Fully nine-tenths of all automobile work is done at a rate much below fifty per cent. of the maximum power of the motor, that is, the motor is working under throttled charge the greater portion of the time. This means that much of the good gas is so mixed with the bad gas at the point of highest compression that considerable of the gasolene vapor is never burned at all. Beside the waste of gasolene, it is noticeable in the bad-smelling exhaust. In many motors under like conditions this loss has been found to average about ten to twenty in favor of the four-cycle, that is, the four cycle motor will work a given weight of car twenty miles per gallon of gasolene, while the two-cycle motor under the same conditions will only make ten miles to the gallon. This is accounted for in several minor ways, but the principal advantage the four-cycle motor has over the two-cycle is in the fact that the spark-plug is located at the gas inlet and in such manner that it fires small charges as efficiently as large charges, or practically so. This is not true in the usual construction of the two-cycle motor for the reason that the spark plug is located at a point the farthest removed from the gas inlet. If, however, the spark plug could be as advantageously located in a two-cycl'e best practice in four-cycle motors there should be a corresponding efiiciency. This efficiency would come about also because the spark could be advanced to its most. advantageous position while the charge could be reduced to the least possible amount necessary to keep the motor turning. Obviously less heat would be wasted in the cooling jacket especially when running idle. No two-cycle engine, as at present constructed, will run idle without missing, while the four-cycle motor has been so developed and perfected that it not only runs idle without missing, but so slowly and quietly as to be motor, as in the construction shown by the practically noiseless. The trouble is that the small charges in the two-cycle engine will not fire becausethey are so mixed with the bad gas of the previous explosion. Necessarily the charge must be increased until there is a preponderance of good gas and the speed of the carcontrolled to such an extent as is possible by retarding the spark. As is well known to gasolene motor engineers, economy and efficiency is obtained by an advanced spark and a throttled charge. This has, to the present time, 'in two-cycle motors, been an impossibility, principally because as stated above the spark plug is placed at the most remote position, insteadof being placed so that it sparks in a charge of good gas no matter how small the charge. If the firing begins in good gas then practically all the gas is converted into power, while, if the spark occurs in a poor mixture, the mixture is fired with di'fiiculty and often not at all until enriched by the second charge. The result is erratic running and uneven firing, that is, running light the motor stutters.

The present construction incorporates the desirable features of a four cycle motor, that is, economy of gas with silent running and even explosions while running idle or at light work, while at the same time retaining all the features of simplicity of construction, easy cooling, etc, of the ordinary two-cycle 'motor. Heretofore when this desirable end was sought to be accomplished, baiiie-plates, pockets, or other confining and irregular shapes were employed on the top of the pis ton (usually), and these, getting red hotby the enveloping flame of the explosion, ignited the gas as it entered, and before the spark plug got a chance to fire the charge,

stroke; Fig. 2 .is "a similar sectional view the piston is down, puts the crank-case in ment of the invention the spark 'the piston; 7"the wateracket spaces; 8 a

- vice for firing 8, as explained. in Patent No.972,379, is to prevent back-firing. And this device, whether multi-tubular or gauze, is usually termed a screen, and in the claims this is what is meant.

. What I claim is 1. In a gasengine, reciprocating therein, 2. located outside of the the water-jacket space upper end of the communication cylinder,

thus creating back-pressure, loss of power, an excessively hot engine, etc., defeating the very end sought.

In the construction shown in the present plug is placed at the point of ingress of the gas, and in a con-- fined passage, and overheating prevented by having this narrow passage water-jacketed.

In the drawings, Figure l is a sectional view of an engine cylinder constructed in accordance with this invention, and having a piston therein at the top of the piston a cylinder, a piston longitudinal passa e cylinder but within of said cylinder, the passage being in open with the upper end of said :with the piston at the bottom of its stroke; opened and closed by the reciprocation of Fig. 3 is a; vertical sectional view of the pisthe piston, and a spark-plug located at the ton; and Fig. 4 a cross section view of the lower or ingress end of the assagepiston, on line w-y. 2. In a gas engine, a cyhnder, a iston In all the figures like symbols refer to like parts, in which 1 is a cylinder of the. engine; 2 a piston therein; 3a connecting rod; i an exhaust.

port; '5 a combustion passage in communication with the combustion space 6 above reciprocating therein, a longitudina passage located outside of the cylinder but within the water-jacket space of said cylinder, the upper in open communication with the upper en of saidcylinder, the lower end adapted to be opened and closed by thereciprocation of the piston, a spark-plug located at the lower or ingress end of the passage, said piston having a plurality of rings so located .thereon as to lie on each side of the ingress end of the passage when the piston is at the upper end of its stroke.

' In a gas engine, a cylinder, a piston Qreciprocating therein, a longitudinal passage located outside of the cylinder but within the water-jacket space of said cylinder, the upper end of the passage being in open communication with the'upper end of said cylinder, the lower end adapted to be ;opened and closed'by the reciprocation of the piston, said piston having a plurality tubular passage in the piston which, when communication with the combustion passage; 9 a spark-plug, or other suitable dethe charge; and 10 piston rings of which nine are shown.

The operation of the engine, obvious to those skilled in the art, is as follows: Carbureted gas is drawn into the crank-case from the carburetor (not shown) in the usual manner, 6. e., by the upward movepiston; and by its downward movement is 'forced through the tubular passage 8 into the combustion passage 5, driving ahead of it the bad gas remaining after the revious xplosio -;If the throtof rings thereon so located as to lie on each tle is wid e. open the combustion space 6 Slde 0f the ingress'end of the passage when above the piston will be completely filled, the piston is at the upper end of its stroke. and on the ignition of the charge the maxi- In g S engine, a cylinder, a piston mum pressure will be exerted on the piston. r lpr catlng therein, a longitudinal pas- If, however, the throttleis but slightly open g ed utside of the cylinder but .the' combustion passage only may be fill d within the water-jacket space of said cylinand none overflow into the combustion cler, theupper end of the passage being in space above the piston. This small charge open communication With'the upper end of will be just as efiicient in proportion to its said cylinder, the lower end adapted to be volume as was the larger charge for it was opened n Closed by e r ciproc tion of compressed to practically the same extent the pi n. a Piston ha ing a Screened and none was mixed with the bad gas of the bypass therein communicating with the previous explosion. It will, therefore, be a p g Wh n th pi t n is at the lower obvious that the spark-plug is always swept 6nd ts S roke.

by the fresh charge, be it large or small, and In t im ny r of I have a-fiiXed my the ignition hwill Ibo just as t i i one signature in presence of two witnesses.

case as in t e ot er, althou h the 'char e and consequent impulse may be only ju t CHARLES FRANCIS JENKINS ,sufiicient to keep the engine turning over, Witnesses:

and without missing a single explosion. G. Love,

he purpose of, the multi-tubular passage JAMES L. CRAWFORD.

a Copies of this patent'moy be obtained for five cents each, by Washington, 110.

end of the passage being the lower end adapted to be

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