US1827818A

US1827818A - Internal combustion engine

Info

Publication number: US1827818A
Application number: US489793A
Authority: US
Inventors: Finn T Irgens
Original assignee: Outboard Motor Corp
Current assignee: Outboard Motor Corp
Priority date: 1930-10-20
Filing date: 1930-10-20
Publication date: 1931-10-20
Anticipated expiration: 1948-10-20

Description

ct. 1931. F, T, |RGEN5 1,827,818

' INTERNAL COMBUSTION ENGINE Filed oct. zo, 195o Paaren 'ea o, isi

rim; r. menne, or MILWAUKEE, Wisconsin, .assrenen fro onrnfoann More conrona'rron, or mmmunnn, wisconsin, a conrona'rron or nrcnreen XNTETRNL GOMBYISTKN EB'GNE .ppicaton filed October 20, 1%0. Serial No. 89393.

rihis invention relates to improvements in interna?` combustion engines.

lt is the object of the present invention to increase the volumetric eficiency of an ins ternal combustion engine. My invention is illustrated in a two cycle engine but certain features of it are applicable to any engine.

l seek to accomplish the indicated result in several different ways involving, first, the in provision of a duplex valve structure and two sep-arate mixtureadmission ports, thereby obtaining twice as much valve opening without increasing the dimensions of the parts as would be possible with the use of a single port of similar angular extent; secondly, by separately controlling the passages leading to the two portsopening into the crank case compression chamber and by advancing the timing of the valve controlling the port whichl is open only at high engine speeds, whereby in effect to increase the valve opening athigh engine speeds and thereby to compensate for the effect of mixture inertia at such speeds; thirdly, by varying the relative dimensions ofthe passages leading to the respective ports so that the passage which is open only at high engine speeds will have somewhat greater capacity than the low speed passage, whereby additionally to compensate for the effect'of mixture inertia which is relatively pronounced at high engine speeds; and, fourthly, by using a multiple manifold and opening and closing the several manifolds successively, thereby approaching a condition of constant velocity of mixture travel and avoiding the pockets and dead spots and condensationvof fuell occasioned by the throttled passage of mixture at low velocity through a single manifold large enough to handle eiliciently the high velocity requirements. l

It is my further purpose, by the passage design aforesaid, to tend to equalize the4 flow to the crank case compression chamber as between the denser and lighter components of the mixture so as to ensure the proper delivery of all material, and particularly to ini crease the velocity in the .lower of thepasz' 1 sages to overcome the tendency of the heavier material to collect therein. By cutting 0E the vtion, taken in the plane indicated at 2-2 in upper passage altogether at high engine speeds, l force all of the mixture to traverse the lower passage, thereby maintaining as high a velocity in the lower passage at lhalf speed as is existent at full speed. By thus compensating my improved engine for changes of speed, i seek to obtain more power at higher speeds and more uniform results at all speeds than is possible in the use of any engine from which my invention is absent.

ln the drawings:

Figure 1 is a fragmentary side of elevation ofv an outboard motor engine showing 1n vertical axial section the crank case of a two cylinder opposed two cycle engine/embodying this invention, the fuel tank 'and other parts lacking in pertinency to the present disclosure being omitted.

Figure 2 isa detail view in transverse sec- Fig. 1.

Figure 3 is a detail view in horizontal sec# tion, taken in the plane indicated at 3--3 in Fig. 1. p v

Figure 4 is a detail View of the intermediate crank disk as it appears when viewed in plan, one ofthe crank pins being shown in cross section taken in the plane indicated at 4-4 in Fig. l. A l

Figure 5 is a' view taken in horizontal section in the plane indicated at 5-5 in Fig. 1.

Like parts are identified by the same reference characters throughout the several views.

The bracket 6 carries a. bearing sleeve' 7 in which the engine support 8 .is swiveled. Mounted on the engine support is the closure cap 9 for crank case 10, the crank case and closure cap having aligned bearings 11 and 12 for the crank shaft 15.

Openin op ositely into the interior compression cam er of crank case 10 through the ends thereof, are the

ports

16 and 17 leading to which are manifold passageslS and 19 respectively, which are formed in the metal of the crank case. A carburetor 20 providesv 95 extensions of these passages uniting in the jet passage 21 into which jet 22 projects laterally from float chamber 23. rihe carburetor provides a taperingv partition `at 24 which divides the extension of

passages

18 and 19 ma and co-acts with the throttle valve which comprises a segment of a cylinder journaled in a cylindrical extension of jet passage 21 as shownv in Figs. 1 and 2.l

The inlet fitting 27 provides an extension of the jet passage 21 whereby such passage is bent back upon itself across the throttle valve chamber, thereby protecting the inlet from spray in outboard motor use. A choke valve at 28 restricts the inlet passage for the usual purpose.

The upper and

lower inlet ports

16 and 17, whereby the mixture is admitted to the crank case, are controlled by

crank cheek valves

29 and 30 which are preferablyintegral with the crank shaft 15 and connected by

cranks

31 and 32 and an intermediate che-ek 33. Each of the upper and

lower cheeks

29 and 30 has a segmental opening registerable with its '

respective port

16 or 17, as shown in Figures 3 and 5. The respective openings in the

valve cheeks

29 and 30 are preferably extended into the crank shaft at 34, as shown in Figure 5, thereby greatly increasing the volumetric eiciencyof the valve by increasing its area without changing its overall dimensions.

lt is particularly to be noted that the segmental opening in valve disk 29 is angularly advanced with respect tothe segmental opening in valve disk 30, and as a result, port 16 will be opened and closed somewhatearlier than port 17.. lligures 8, 4 and 5 show the relative positions of the parts in a given crank shaft position, and it will be observed that the valve disk 29 has a partially uncovered port 16 in Figure 3, while disk 30 is just at the point of uncovering its port 17 in Figure 5. rlhe disposition of throttle'valve 25 with respect to

manifold passages

18 and 19 is such that passage 19 is first to open and last to close. Thus, passage 18 and port- 16 are used only at relatively wide open positions of the throttle valve and consequently high engine speeds.

Theoretically, the valve timing, like the ignition timing, should be advanced at high engine speeds, since the inertia of the mixture is such that an appreciable amount of time is required to set it in motion and stop it. At high engine speeds the time interval available for starting and stopping the mixture has decreased and in order to compensate for this decrease the valve timing should be advanced, particularly as to the time ofl opening. This is impractical in an ordinary single manifold engine, but since dual man1- folding is being used in this engine and since V dual valves are provided to open and close the respective manifold ports, it becomes possible to approach optimum conditions by advancing the timing of one valve with respect to the other and thereby increasing the relative period for which mixture is admitted to the crank case chamber and advancing the relative time at which mixtureis first set in motion by the opening of the valve.

Figure 1 shows the position lof the throttle valve at full engine speed. It will be observed that manifold passage 18 is larger than manifold passage 19, thereby compensating for increased resist-ance to liow at high mixture velocities.4 As the throttle valve is closed, passage 18 will be wholly cut off, while passage 19 remains open. And because of the reduction in engine speed and conseqently reduced demand for mixture, the velocity through passage 19 under these circumstances will be approximately thesame as the velocity through this passage at wide open throtthan is possible-between valve 29 and the top of the crank case. The engine shown is arranged upon a vertical axis so that the weight of the crank shaft, fly wheel and associated parts is carried by the crank case through the crank cheek and valve disk 30. T he close fit between disk 30 and the bottom of the cra-nk case minimizes leakage at this point and 'any leakage which occurs past disk 29will be unimportant for the reason that at low speeds the passage 18 is wholly cut oli" by throttle valve 25 and at high speeds the slight amount of leakage which might occur would be unirnportant.

The use of multiple manifold passages and admission ports makes it possible to double the area of valve opening without increasing the size .of the parts, thereby greatly increasing volumetric efhciency. lt will be obvious that by using additional valves and manifolds, a still further increase could be made, each manifold being preferably cut off in succession in order to approach a condition of substantially constant velocity through the several manifolds.

The peculiar form of the central cheek33 is determined by its weight and the desirability of disposing that vweight in a manner to counterbalance the loss of weight in

cheeks

29 and 30 occasioned by the provision of the segmental openings therein.

Although l have chosen to illustrate the application of this invention to a two cylinder two cycle engine of co iventional design having a single crank case chamber, those skilled in the art will readily understand that the provision of multiple manifolding and multiplevalve control subject to throttle means for opening and closing the manifolds successively, is a feature applicable to any kind of internal combustion engine.

This application 1s a continuation in part of my application, Serial No. 405,561, led

November 8th, 1929, and contains claimed subject matter divided therefrom. -I

I cla-im: 1. In an internalfcombustion engine, the

combination with a mixture 'receiving chamber and a lurality of mixture delivering passages lea ing thereto, of mechanically operated valve means controlling the time of miX- ture delivery to said chamber, means for supplying mixture to the several passages, and throttle valve means for successively opening and closing said passages.

lau

3. In an internal combustion engine, the

combination with a mixture receiving chamber and a plurality of mixture delivering passages leading thereto, of mechanically operated valve means controlling the ltime of mixture delivery to said chamber, means for supplying mixture to the several passages, and throttlev valve means for successively opening and closing said passages, the mechanically operated valve in the passage last opened by said throttle valve means being timed to open in advance of the opening of the mechanically operated valve in another of said passages.

4. In an internal combustion engine provided with a crank shaft and a mixture receiving chamber, the combination with a plurality of manifold passages leading to said chamber, and means for supplying mixture to each of said passages, of vrotary valve members connected with said crank shaft for the individualcontrol of delivery of mixture to said chamber from each of said passages in timed relation to the operation of said shaft, and manually operable throttle valve means for successively opening and closing the several passages.

5. In an engine, the combination with a mixing chamber and a mixture receiving chamber of a plurality of manifold passages affording potential communication between said chambers and throttle valve means for successively opening and closlng said passages.

6. In an internal combustion engine, the combination with a mixing-chamber and a mixture receiving chamber. of a plurality7 of manifold passages affording communication between Vsaid chambers and varying in cross-sectional area, and throttle valve means for successively opening and closing the sev-` eral assages, a passage of relatively large area eing last to o en and first to close'.

7 The combination in an internal combustionvengine with a mixing chamber and a mixture receiving chamber, of a plurality of manifold passages affording communication between said chambers at differing levels,

and a throttle valve for successively opening and closing said passages, the lowest of said passages being the first -to be opened and the last to be closed.

8. In an internal combustion engine, the

combination with a crank shaft, a mixing chamber and a mixture receiving chamber,

-of a plurality of manifold passages affording communication between said chambers and 'provided with individual valves controlling the delivery of mixture to said receiving chamber, and means connecting the respective valves with the crank shaft for opening and closing in consecutively timed relation.

9. In an internal combustion engine, the

combination with a `crank shaft, a mixing chamber and a mixture receiving chamber, of a plurality of manifold passages affording communication between said chambers and provided with individual valves controlling the delivery of mixture to said receiving chamber, and means connecting the respective valves with the crank shaft for opening and. closing in consecutively timed relation,

and throttle valve means for successively opening and closing communication between said mixing chamber and passages, the passage timed for first opening by the crank shaft operated valve being last opened and first closed by said throttle valve means.

10. In an engine, the combination with an upright shaft carrying valve disks, and a mixture receiving chamber provided with ports controlled by said disks, of a carburetor mixing chamber, upper and lower manifold passages extending from said mixing chamber to said ports, and a throttle valve movable successively across the openings 'of said passages. I

11. In a two cycle engine, the combination with a crank case compression chamber provided with ports and a crank shaft, ofcrank shaft operated valve means controlling the repective ports and timed for the opening and closing of one port in advance of the respective opening and closing of the other, a carburetor provided with a mixing chamber,

`manifold passages leading from the mixing of the engine cycle during which mixture passes` from said chamber to said ports.

13. In an internal combustion engine adapted for a predetermined cycle of oper-` ved with valve members having openings registerable with the respective ports, of .acarburetor mixing chamber, -manifold passages leading from said chamber to the' respective ports, and an oscillatable throttle valve movable successively across said passages.

15. lAn internal combustion engine of the type having crank case compression, said engine comprising a crank case, a crank shaft rotatable therein, manifold passages leading to said crank case, valve means connected with said crank shaft for controlling com munication between said passages and case, means for supplying carbureted air to said passages, and throttle valve means adapted to open and close. said passages successively.

16. A two cycle internal combustion 'engine comprising the combination with a vertical crank shaft and a crank case provided with upper and lower bearings for said shaft, of crank cheeks carried by said shaft and operating adjacent the top and bottom of said crank case, said cheeks being provided with openings and the ends of said crank case being provided with ports, carbureting means for supplying mixture to said crank case, a lurality of manifold passages adapted to deliver the mixture from thea carbureting means to said ports subject to the control of said crank cheeks, and throttle valve means for the respective passages positioned for the successive opening and closing thereof.

17. A two cycle internal combustion engine comprising the combination with a vertical crank shaft and a crank case provided with upper and lower bearings for said shaft, of crank cheeks carried by said shaft and operating adjacent the top and bottomof said crank case, said cheeks being provided with openings, and the ends of said crank case being provided with ports, carbureting means for supplying mixture to said crank case, a plurality of manifold passages adapted to deliver the mixture from the carbureting means Ito said ports subject tothe control of said l throttling air admission to said ports.

'the respective, passages positioned for the successive openin and closing thereof, one of said passagesA eing Vof larger cross section than the other and extending there'- above and arranged to be last opened by said throttle valve means.

18. A two cycle internal combustion engine comprising the combination with a vertical crank shaft and a crank `case provided with upper and lower bearings for said shaft.

lof crank cheeks carried by said shaft and successive opening and closing thereof, one

of said passages being of larger cross section thanthe other and extending thereabove and arranged to be last opened by said throttle valve means.-

19. In a two cycle engine, the combination with .a compression chamber provided with air admission dports, of a crank shaft, crank shaft operate valve means controlling the respective ports and timed for the opening and closing of one port in advance of the respective .opening and closing of the other. and throttle valve means for successively 20. ln a two cycle engine, the combination with a compression chamber provided with ports, of a crank shaft, crank shaft operated valve means controlling the respective ports and timed for the opening and closing of one port in advance of the respective opening and closing of the other, an air inlet chamber arranged for air delivery to the respective ports, and means for successively throttling communication between said air inletchamber and ports, said means being adapted to 4throttle communication with the port first opened by said crank shaft operated valve means before throttling communication with the port later opened by said valve means.

21. In a two cycle engine, the combination with a compression chamber provided with air admission ports and manifolds leading thereto, of a crank shaft, crankshaft operated valve means controlling the respective ports and time for the closing of one port in advance of the closing of the other, and throt `tle valve means associated with the respective manifolds and organized for the'successive throttling of airV admission therethrough .to said ports.

22. In a two cycle engine, the combination -with a crank case'compression chamber procrank cheeks, andthrottle valve means for vided with air admission ports, of a crank means for successiv mamie t1ve port 1n advance of with the respective ports and timed for theclosin E of one the closing of t e other,

Y 5 acarburetor mixing chamber communicating Iorts and throttle valve e y throttln communi cation between said cham 1" and the respective ports.

Fm T. mGENs(