US1919829A

US1919829A - Two-cycle internal combustion engine

Info

Publication number: US1919829A
Application number: US566244A
Authority: US
Inventors: Charles G Curtis; Earle R Newton
Original assignee: Individual
Current assignee: Individual
Priority date: 1931-10-01
Filing date: 1931-10-01
Publication date: 1933-07-25
Anticipated expiration: 1950-07-25

Description

Jul 25, 1933.

c. G. CURTIS ET AL 1,919,829

TWO-CYCLE INTERNAL COMBUSTION ENGINE Filed Oct. 1, 1951 2 sheets-sheet 1 TWN y 1933. v c. G. CURTIS ETIAL ,919,829

TWO-CYCLE INTERNAL COMBUSTION ENGINE Filed 001;. 1, 193i 2 Sheets-Sheet 2 I c l 5 3 I day I patented July 25, 11933 inten CHLES Gr. CURTIS, OF NEW YORK, AND EARLE R. NEWTOIT, @313 JAMAICA,'NEW YQRK TWO-CYCIJE INTERNAL COMBUSTION ENGINE Application filed October 1, 1931. Serial No. 566,244.

This invention relates to the scavenging and supercharging of two cycle internal combustion engine cylinders of the portscavenged type. It applies particularly to long stroke engines in which the path of the scavenging air through .the cylinder is long.

The invention provides for a scavenging system comprising exhaust ports arranged on one side of the cylinder near the end of the stroke remote from the combustion end,

and air inlet ports arranged one above the other in two transverse planes,.near the same end, and generally oppositely disposed to the exhaust ports. The air inlet ports are characterized in that those in each transverse plane comprise oppositely disposed ports turned back toward the inlet side of the cylinder, like those described and claimed in applicants earlier United States Patents, Nos. 1,777,827 and 1,780,175.

The invention is applicable to both single acting and double acting two cycle engines, with or without inlet valves or exhaust valves.

The object of the invention is to improve the scavenging efficiency of two cycle engine cylinders which utilize inlet-ports arranged in two transverse planes. The features and advantage of the invention appear in the description which follows and in the drawings. The invention, however, is not limited to the specific arrangements illustrated.

' Figure 1 is a sectional elevation of, an engine to which the invention is applicable The engine shown is a double acting engine with air inlet ports oppositely disposed to the exhaust port arranged in three transverse planes. The air inlet ports in the intermediate plane are arranged to serve each end of the double acting cylinder alternately so that air-inlet ports in two planes are in use during. the scavenging of each end of the cylinder.

Fig. 2 is a transverse, somewhat diagrammatic section through the air inlet ports in one transverse plane in accordance. with the invention. In the illustrated embodiment the inlet ports in each transverse plane are similar, that is, corresponding ports in the two planes are alike, hence only one transverse section is shown. Figs. 3, 4, 5 and 6 are diagramsshowing longitudinal sections through the various ports in. one plane and showing a changing obliquity of the ports to the longitudinal axis of the cylinder in accordance with one embodiment of the invention.

Heretofore inlet-ports arranged in two planes have used either radial ports or ports turned toward the exhaust port side of the cylinder and these arrangements do not givegood scavenging efiiciency although they do give a supercharge to the cylinder. By directing the ports in each plane back toward the inlet side of the cylinder the same supercharge effect is obtained and the scavenging efficiency is very greatly improved.

In carrying out the invention we provide a two stroke internal combustion' engine 7 comprising a cylinder 1, a reciprocating piston 2, exhaust ports 3, arranged in one side of the cylinder wall near the end of the stroke remote from the combustion end, and sets of air inlet ports 4' and 5 arranged in 7 two planes near the same end of the stroke in that part of the arc of circumference not occupied-by the exhaust ports, that is, in that part of the cylinder wall generally op posite the exhaust ports.

In the drawings the sets of-dnlet ports 4 and 5 in each transverse plane are similar, that is, corresponding'ports in the two planes are alike. They have the same angles, the

same height, the same width and are in the 35 same longitudinal plane. However, the ports in the two planes may be dissimilar, that is, the ports in one plane may .difier in size, angle or location fromthe ports in the other p ane, provided each plane comprises 9% oppositely disposed ports turned back toward the inlet side of the cylinder. The ports in each plane are shown divided into two groups, fourports to each group. They are designated 4 4 4 4 4 4 4,, 4 and 5 5 5,, 5 5 5,, 5 5 and are arranged symmetrically about the center line 6 and turned back toward the inlet side of the cylinder. The air-streams from the ports 4 to 4 inclusive oppose the streams from the ports 4 to 4 inclusive. Similarly the two groups of ports in plane or set 5 oppose each other. The

middle ports

4 and 4 are steeply oblique to the" longitudinal axis of the cylinder and the

end ports

4 and 4 are of lesser angle. The same is true of the ports in plane or set 5. This port arrangement prevents the incoming air from flowing transversely, or directly, across the cylinder to the exhaust ports and causes it to flow in a more or less longitudinal direction on the inlet port side of the cylinder to the cylinder cover and down the exhaust port side of the cylinder to the exhaust.

The operation of the two stroke cycle engine, having air inlet ports arranged in two transverse planes iswell known and such engines are in common practice, and since the embodying of this invention in that engine does not in any way modify the cycle of operations it need not be described here. What we claim as new and desire to secure by'llietters Patent of the United States isf 1. A two-cycle internal combustion engine comprising a cylinder, exhaust ports and air inlet ports arranged in that end of the cylinder wall remote from the combustion end, the exhaust ports on one side and the air inlet ports on the other, said air inlet ports arranged in two transverse planes, the air inlet ports in each of the said planes comprising oppositely disposed ports turned back toward the inlet side of the cylinder wall so arranged that the air streams issuing from them come together as opposing streams and set up a flow toward the combustion end of the cylinder on the inlet side.

2. A double-acting two-cycle internal combustion engine comprising a cylinder, ex-

amaze haust ports and air inlet ports arranged in the cylinder remote from the combustion end, exhaust ports on one side and the air inlet ports on the other, said air inlet ports arranged in three transverse planes, the air inlet ports in each of said planes comprising oppositely disposed ports turned back toward the inlet side of the cylinder wall, the ports in the middle plane serving both ends of the double-acting cylinder alternately.

3. A two-cycle internal combustion engine comprising a cylinder, exhaust ports in one side ofthe cylinder wall and remote from the combustion end, air inlet ports arranged generally opposite the exhaust ports in two planes or sets, the ports in the middle portion of each set being oblique to the longitudinal axis of, the cylinder, the ports in the end portions of each set being less steeply oblique and turned back toward the inlet side of the cylinder wall.

4. An engine according to claim 1 further characterized by the ports in the two planes being similar in that there are the same number of ports in each plane and corresponding ports in the two transverse planes are in the same longitudinal plane, have the same angles and are of the same size.

5. An engine according to claim 1 wherein the ports in the upper transverse plane reach higher up in the cylinder than the exhaust ports, and further comprising valve-means controlling said upper inlet-ports arranged to stay open after the exhaust ports are closed.

" CHARLES G. CURTIS.

EARLE R NEWTON.