US874634A

US874634A - Two-cycle engine.

Info

Publication number: US874634A
Application number: US31857006A
Authority: US
Inventors: William A St Germain
Original assignee: Individual
Current assignee: Individual
Priority date: 1906-05-24
Filing date: 1906-05-24
Publication date: 1907-12-24
Anticipated expiration: 1924-12-24

Description

'PATENTBD 1330524, 19o?.

W. A. ST. GERMAIN. TWO CYCLE ENGINE.. APBPLIOATIOE FILED HAY 24| 190B.

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. No. 874,634. PATENTED DBO. 24, 1907.

W. A. sT. GERMAIN. TWO CYCLE ENGINE.

APPLIGAIVYION FILD MAY 24,'1906.

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. MII/IA [Nl/ENTO/e Y wiLLiAM A. sT. GERMAIN Ol" GREENVILLE, MAINE.

'BEVO-CYCLE ENGINE.

Specification of Letters Patent.

- Patented Dec. 24, 1 907.

Application filed May 24.1906- Serial No. 318.570. i

To all 'whom 'it may concern.' A

Be it known that I, WILLIAM A. ST. Gna- MA1N, a citizen of the United States, residing at Greenville, in the county oi Piscataquis and State of Maine, have invented a new and L useful TwolCycle Engine, of which the following is aspeciiication.

This invention relates to two cycleinternal combustion engines, and .has for its principal object to provide a double piston two cycle engine so designed as to secure two working strokes for each revolution. oi. the crank shaft.

A further object of the invention is to provide a double piston two cycle engine in which the compression chambers are ar-` ranged for connection with a single source of supply, such for instance as a carbureter, and y further to provide for the more positive closing and seating of the valves which control communication between the source of supply and the compression chambers.

With these and other objects iii view, as

will more fully hereinafter appear, the invention cons-ists in certain novel features of coni struction and arrangement of parts, hereinl after fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes inthe form, proportions, size and minor 'details of the strucvture may be made without departing from the spirit-or sacrificing any of the-advantages yof the invention. Y

In. the accompanying drawings Figure 1 is a sectional elevation of a two cycle engine constructed in accordance with the invention.

the same taken on the plane at right a les to the section of Fig. 1 Fig. 3 is a plan view of the engine.

Similar numerals of reference are employed to indicate corresponding parts throughout the several figures of the drawings.

The upper and lower cylinders 10 and 1l are preieijablycast integral with the upper y be introduced into the lower cylinder are compressed.

Arranged within the upper and lower cylindeis :

ire pistons

16 and 17, respectively, said pistons being rigidly connected to Fig. 2 is a vertical sectional' view of each I l other by. a rod 18, and the lower piston being connected to the crank shaft by a rod 1.9.

; throughpstuling boxes 20 formed at the ad. jacent end of the two cylinders, said stuiiing boxes being preferably .arranged to contain metallic rings 21 that are held in place'by gland nuts 22, although any other suitable torni oi' b ox may be employed for the pur' pose of preventing leakage between the ex- V'lflie cylinder heads' arev spaced from each other by a water .chamber 23, in communication with the outer water. jacket 24 that surrounds the explosion chambers .of both cyllinders, any suitable connection being eml ployed to promote the circulation`of water through the jacket.

The main casting is preferably so formed as to include a portion of a .compression 'The .pieten rod 18 is arranged to travel plosion chambers and' the two cylinders.

chamber 25 that ,is in free communication with the upper open end of the cylinder 10,

a .boss 27- on the upper end of the cylinder, and such other connections as may be necesi sary. The chamber 25 communicates with the upper end of the cylinder l() through the space s 26 on opposite sides of the boss 27', Fig. 2. The lower compression chamber communicates with. the upper end of the cylinder 11 through a port V2S which is opened by the piston 17, as the' latter completes its down or in stroke, and the compression chamber 25' is placed in communication. with the lower end of the cylinder 10 by'a port 29 that is opened by piston 16, as the latter completes its upward or out stroke, and the pistons are provided with -the usual deflecting plates 30v for the-purpose of diigecting the fresh charges toward the heads of the explosion chambers.

Leading from the two cylinders at points diametrically opposite the

inlet ports

28 and 29 are exhaust ports 33 and 14 which com municate with an exhaust pipe 35, and said exhaust pipe may be reversed in order to direct the exhausted gases upward. instead of downward, as showmin Fig. l.

At one side of the cvlindei's is arranged a valve casing 36 Athat preferably is cylindrical inV lorni and is divided by a pair of par.

held in place by a suitable bolt 27, entering l or other suitable source of supply. The i of the engine is a working stroke, and two upper chamber is connected by a pipe to the compression chamber 25 of the upper cylinder, While the lower 'chamber of the valve casing is connected by a pipe 41 to thecranl casing or compression chamber of the lower cylinder. The two ported

partitions

37 and 38 are provided with oppositely facing valve seats 46 and 47', and have guides e5 for the reception of a slidable valve stem 45 having two oppositely facing valves 46 and 47, one of lwhich is a1- ways closed, while the other is open.

ln the operation of the engine as thus far described, it will be seen that when the parts are in the positions shown in Fig. 1, the

upper piston 16 has completed a working stroke, and the products of combustion are escaping through the port 34, while the fresh charge is entering the cylinder through the port 29, and at this time the valve 46 is held K closed by the pressure ofgas or erqylosive mixture in said chamber The lower` piston 17 has `iust completed an up or .vorlring compression stroke, and the compressed charge in the upper portion o'rl the cylinder about being ignited.v this upward stroke oi the lower piston has created a partial vacuum within the lowerconniression chainber, resulting in the opening of the valve 47, so that a fresh charge may tlcw from the carburetor into the cranlr easing. \\,"hcn the charge is ignited in the upper end ol the eviinder 1l, the piston ,17 will be l'orced down and. will compress the charge pre.` nisly drawn into the cranlr casing, and the increase in pressure 'which results in the lower portion ol the valve ,casing 36 tends to more the Valve l? to closed position. At the same time downward nuwement ol' the piston 16 is creating a partial vacuum in the chamlur 255, so that there is a tendency to lili. the valve 45T, and these l'orccs, operaiing simultaneously on the valves, will more valve i7 posi iveiy to closed position and will open the valve 1.6, so that a fresh charge may il'low from the carburetor into the chamber 25 as the down stroke continues. vwhen the piston 17 near the limit ci its down strolre, the escape port 33 is opened and thel products of combustion will start to escape from the cylinder 11, and on slight'lurther 'movement, the irdet port- 26 will be opened and the i'resh charge of gas entering the upper end of the cylinder will be directed by the deliector 30 toward the head ot' the efr- `plosion chamber and will act to sweep out all or the greater part of the exhaust gases through the port 33, so that when the up stroke of the piston 17 commences,V and 'the ports are closed, the cylinder will contain nothing but die fresh charge oil gas.. When the de wn stroke of the piwon is completed, the charge in the upper chamber l0 is compressed and is ignited, so that each stroke .suitable manner, and in Fig. 2 jump spari crasse working strokes will occur for each revolution of the cranlr shaft. A

' The working charges may be ignited in an.

plugs 5() have been shown in recesses near the heads of the explosion chambers. ".hese are suitably connected to an adjustable c ommutator 51 that is disposed at the upper end of a vertical shaft 52 comiected by a skew gearing 55 to the main shaft.

It will bel seen that no valves are employed in this engine, with. the exception of those between the compression chambers and the carbureter or other source of supply, and thathan engine of practically' double the horse power of a single acting two cycle engine is secured, and the weight is but slightly greater than that ot a single acting engine.

l claim ,t 1. ln an internal combustionengine, a pair of cylinders arranged head to head and in alinemcnt with each other, pistons in said cylinders, a piston rod extending through the head cylinder' and to which both pistons are secured, a crank shaft connected to one of the pistons, upper and lower compression chambers connected to the open ends of the cylinders, inlet ports leading from the compression chambers through the Walls or" the cylinders, exhaust ports leading from the cylinders and arranged to be uncovered by the pistons at` the outer limits of their strolr-es, all of said ports being controlled by the pistons, a valve chamber intermediate the compression chambers and havinfr a fluid inlet, and valves arranged in sai Valve chamber and controllingl communication between the latter and the compression chambers.

2. in an internal combustion engine, a pair of cylinders arranged tandem and having their explosion chambers adjacent to each other, a crank casing in communication with the open end of the inner cylinder, and forming a compression chamber, a second compression chamber in free communication with the open end of the other cylinder, piston controlled inlet ports leading from the compression chambers to the respective cylinders, exhaust ports leading fromv the cylinders, a valve casing in communication With a source of' supply and with the two compression chambers, and connected and simultaneously acting valves arranged in said casing for alternately placing the chambers in communication with the source of supply.

3. ln an internal combustion engine, a pair of cylinders arranged tandem, compression chambers in communication with the open ends ,of the cylinders, ports leading from the` compression chambers through the walls of said cylinders, exhaust ports also leading through the Walls of the cylinders, a pair ci connected pistons disposed in said cylinders and controlling the ports, a valve casing in communication with a source of supply, and with the two compression chambers, and a pair of valves arranged. in said valvel chamber, said valves being simultaneously acted upon by the pressure from one `chamber and the suction or partial vacuum through the stuiling boxes, pistons secured to the rod and arranged within-the cylinders,A

upper and lower compression ychambersin communication with the open ends oi the chambers adjacent to each lower. compression chambers, connected valves adapted to the seats, valves being exposed to the pressure of one chamber and the suction or partial vacuum simultaneously formed in the other chamber.

5. ln an internal combustion engine, the combination with. a pair of cylinders, pistons therein, a pairof chambers connected to said cylinders, the pistons operating to simultaneously produce a partial vacuum in one of the chambers. and a compression in the other chamber, a branched supply conduit connected with. the chambers, a valve casing at the point of branching ol the conduit, valves in the casing forcontrolling the sup- 2 ply through each branch ol the conduit,and

a piston rod extending cylinders, piston controlled inlet ports lea'd- 'l ing from said chambers to the ton. controlled exhaust ports .leading -lroni the cylinders, a valve casing, having ported cylinders, pisl partitions and provided with valve seats, 2 said casing being in communication with. a i

source of supply and with the upper and means for connecting the valves multa-neously by the combined eilect of the vacuum iii one chamber andthe compression in. the other.

ln testimony that l claim the vforegoing as my own, l. have hereto affixed my signature in the presence of two witnesses.

l WILLIAM A. ST. ("rllMAlN.

Witnesses'. l`. 7. ALLEN, ll. M. SHAW.

land a pair of said`