US1502918A - Two-cycle internal-combustion engine - Google Patents

Description

- -July 29 1924.

L. L. SCOTT TWO-CYCLE INTERNAL COMBUSTION ENGINE llllll III: Il!

Filed July 31 1922 p Patented July 29, 1924.

UNITED STATES LELAND L. SCOTT, 0F SAVANNAH, MISSOURI.

TWO-CYCLE INTERNAL-COMBUSTION ENGINE.

Application mee my 31, 1922. serial No. 578,669.,

To all whom t may concern:

. Be it known that I, LELAND L. Soo'rr, a citizen of the United States, residing at Savannah, in the county of Andrew and State of Missouri, have invented a certain new and useful Improvement in Two-Cycle Internal-Combustion Engines. of which the following is a complete specification.

This invention relates to two-cycle internal combustion engines and has for one of its objects toproduce a stationary inside head secured to one end of the cylinder and adapted to work in combination `with an inverted cup-shaped piston, machined inside and outside.

Another object is to produce an engine of i the general character mentioned equipped with a new and novel by-pass arrangement whereby a constant and steady suction'shall be maintained on the up stroke of the piston, as well as a constant and steady compression of the mixture in the by-pass chamber on the down stroke of the piston, consequently entirely obviating apause period pending the operation of the piston.

A further object is to provide a ported piston and by-pass structure/of such character that the motor 'can be readily and easily adapted to function with an inlet Avalve of any suitable automatic or mechanical construction and in communication with the by-pass chamber of the engine.

Another object is to obviate the present sluggishness of the ordinary type of twocycle engine, d-ue to the fact that ordinarily the mixture is compressed in the crank case, orv between the piston and a stationary head, and then at the proper time is allowed to escape through a more or less extended bypass chamber into the cylinder. I have found that the sluggishness of an engine, constructed as just described, is due to a more or less condensation of the combustible mixture during` its passage through the bypass, and in order to overcome this diiticulty I- have designed the engine of this application, in which the combustible mixture is compressed in the by-pass chamber itself, and permitted to escape directly into the cylinder.

The objects of the Ainvention are accomplished by providing the by-pass chamber with a long vertical port and forming the piston with a pair of similar spaced ports so arranged that one of' the piston ports is constantly in register with the by-pass port .asiwill be explained in detail, hereinbelow'.

With the objects named in view the invention consists in certain novel and useful features of construction and organization of parts as hereinafter described and claimed; and in order that it may be fully understood, reference is to be had to the accom- The cylinder block 1 is formed with anextension 4 projecting into the crank-case and forming a continuation of the cylinder,

and secured to said extension isa fixed Ainternal cylinder provided with the customary piston rings, and head 5, formed at its lower end with a flange 6 and Asecured in position to the lower end of the part 4 as clearly shown in Figure 1. The lixed cylinder head 5 is, of course, of cylindrical form and is formed at its lower `end with a pair of oppositely disposed vertical slots 6 for the reception of a reciprocating part hereinafter mentioned. A

Mounted in the cylinder for reciprocation therein is a piston -7 provided with suitable external piston rings and formed with an external skirt portion 8, said skirt portion being secured at its lower end toa wrist pin 9 secured to the connecting rod 10, as customary. At its upper end the piston head may or an inlet valve driven mechanically from the crankshaft may be employed if desirable,

said valve to open directly into the by-passV chamber, hereinafter referred to.

n the opposite side of the cylinder a large rectangular port 13a is formed, which is 1n communication with a by-pass chamber 14 closed by a removable cap 15.

' opposite side, is formed with a pair of similar ports 18 and 19 so spaced vertically apart that one of these ports will be constantly in register with the long port 13 in the cylinder wall regardless of the position of the piston.

Theoperation of the engine is`substan- W tially as follows z-Upon the upstroke of the -will be drawn into the engine.

iston, a vacuum will be created between the ottom of the piston and the fixed head 5 and immediately the port 17 registers with the intake port 13, the combustible mixture As one or the other of the ports 18 and 19 constantly register with the oy-pass chamber, upon the commencement of the down stroke, this combustible mixture will be constantly and evenl; compressed in the bypass chamber 14 t rough the long vertica port 13".

Immediately the upper end of the long port 13u is uncovered by the top of the piston, the combustible mixture will rush directl into the firing chamber as will be readily understood.

It will be apparent from the above that by means of the double port arrangement in the piston and the long port in the by-pass chamber, there is a continual and steady increase in the compression on the down stroke of the piston of the combustible mixture in the by-pass chamber, from which it is permitted torush directly into the cylinder. I have found by experiment that when the combustible mixture is compressed between the underside of the piston and the iixed head and then at the proper time permitted to rush around through a b -pass and into the cylinder, there is aresulting sluggishness of o eration due to the fact that there is a con ensation of the mixture pending its journey through the by-pass. With an engine embodying the invention, however, this draw-back is obviated.

From the above description it will be apparent that I have produced a' device of the character described, which possesses all of the features of advantage set forth as desirable, andwhile I have described and claimed the preferred embodiment of the same, I reserve the right to make all changes properly falling wlthin the spirit and scope of the appended claim.

I claim In a two-cycle internal combustion engine, a cylinder having an elongated bore, an internal cylinder head bolted to the extremity of said cylinder and closing the end thereof and being provided with a series of piston rings, a piston for reciprocation in said cylinder and having its internal face in frictional contact with the rings of said internal head, a combustible mixture supply and an exhaust port in said cylinder, a by-pass chamber having a single port with its lower edge in horizontal alinement with the top of the internal head, a pair of ports in said piston; said by-pass and piston ports being so arranged that there shall be an uninterrupted compression of the combustible mixture in the by-pass chamber on the back stroke of the piston, one of saidpiston ports passing beyond the rings of the internal head on the back stroke of the piston, and a supply port in said piston adapted for re istration at times with said cylinder supp y .port and on the back stroke of the piston Ipasing beyond the rings of the internal signature.

LELAND L. SCOTT.

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