USRE20455E - Internal combustion engine - Google Patents

Description

July 27, 1937. F. T. IRGE'NS` INTERNAL COMBUSTION ENGINE original Filel oct. 2o, 1950 Reissues July 27, 1937 UNITED STATES PATENT OFFICE INTERNAL coMUs'rioN ENGINE Finn T. Irgens, Wauwatosa, Wis., assigner to Outboard Motors Corporation, Wis., a corporation of Michigan Milwaukee,

original No. 1,s27,s1sdad october lzo, 1931, SerialNo. 489,793, October 2,0, 1930. Applicationfor reissue October 26, 1935, Serial No.

1o claims. (c1. 12s-'13) vision of a duplex valve structure and two separate mixture admission ports, thereby obtaining twice as much'valve opening without increasing Y the dimensions ofthe parts as would be possible with the use of la single port of similar angular passages leading to the two ports opening into the crank case compression chamberand by ad, vancing the timing of the valve controlling the` port which is open only athigh engine speeds, whereby in effect to increase the valve opening at high engine'speeds and thereby to compensate for the eiect of mixture inertia at such speeds; thirdly, by varying the relative dimensions of the 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 speedpassage, whereby additionally to compensate for the eiect 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 approachingl a condition of constant velocity of mixture travel and avoiding the pockets and dead spots and con- 35 densation of fuel occasioned by the throttled passage of mixture at low velocity through a; single manifold large enough to handle eillciently the high velocity requirements.

It is my further purpose, by the passage del sign aforesaid, to tend to equalize the 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 increase the velocity in the lower of the passages to-overcome the tendency of the heavier material to collect therein. By cutting off theA upper passage altogether `at high engine speeds, I force all of the mixture to traverse the lower passage, thereby maintaining as high a velocity inthe lower passage at half speed as is existent at full speed.V 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 extent; secondly, by separately controlling the` than is possible in the use of any engine from which my invention is absent. t In the drawing:

Figure 1 is a fragmentary side of elevation of lan outboard motor engine showing in vertical axial section the crankcase of a two cylinder opposed two cycle engine embodying this inven tion, lthe fuel tank and other parts lackingin pertinency to the present disclosure being -omitted. 10

Figure 2 is a detail vview in transverse section, taken in the plane indicated at 2-2in Fig. 1.

Figure 3 is a detail view in horizontal section,A taken in the plane indicated at 3-3 in Fig. 1. Figure 4 is a detail view of the intermediate crank disk as it appears when viewed in plan, one of the crank pins being shown in cross section taken in the plane indicated at 4 4 in Fig. l. Figure 5 is a View taken in horizontal section yin the plane indicated at 5-5 in' Fig. 1.

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

The' bracket 6 carries a bearing sleeve I in Y which the engine support 8 isswiveled. Mounted on the engine support is the closure cap 9 for crank case I0, the crank case and closurer cap having alignedbearings II and I2 for the crank vShaft l5.

` x Opening oppositely into the interior compression chamber of crank case Il) through the ends thereof, are ythe ports I6 and I'I leading to which are manifold passages I8 and I9 respectively,

which are formed in the metal of the crank case.

lin'Figs. 1 and 2.

The-inlet fitting 2I provides an extension of the jet passage 2| whereby such passage is bent back upon itself across the throttle valvechamber, thereby protecting the inlet from spray in outboard motor use.4 A choke valveat 28 'restricts the inlet passage for the usual purpose.

The upper and lower inlet ports .I6 and I'I, whereby the mixture is admitted tothe crank case, are controlledby crank cheek Valves 297 and 30 which are preferably integral with the crank shaft I 5 and connected by cranks 3| and 32 and an intermediate cheek 33. Each of the 'upper' and lowercheeks 29 and 3 0 has a segmental open- CFI ing registerablewith its respective port I6 or I'I, as shown in :Figures 3 and 5. The respective openings in the valve cheeks 29 and 39 are preferably extended into the crank shaft at 34., as

with respectto the segmental openingv in valve disk 30, and as a result, port I6 will be opened and closed somewhat earlier than port II. Figures 3, 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 I6 in Figure 3, whilegdisk 30 is just at the point of uncovering its port I1 in Figure 5. The disposition of throttle valve 25 with respect to manifold passages I8 and I9 isY such that passage I9 is first to open and lastv to close. Thus, passage IB and port I6. 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 athigh engine speeds, since thevinertia of the mixture is such that an appreciable amount of time is required to set it in ing.

in motion by the opening of the valve.

motion: and stop it. 4At high engine speeds the time interval available for starting and stopping the mixture has decreased and in order to compensate for this decrease Vthe -valve timing should be advanced, particularly as to the time of open- This isimpractical in an ordinary single manifold engine, but since dual manifolding is being used in this engine and since dual valves are provided to open and close the respective manifold ports, it becomes possible to approach optimum conditions by advancing the timingof 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 mixture is first set Figure l shows the position of the throttle valve at full engine speed. It will be observed that manifold passage I8 is larger than manifold passage I9, thereby compensating for increased resistance to flow at high mixture velocities. As the throttle valve is closed, passage I8 will be wholly cut oil', while passage I9 remains open. And because of the reduction in engine speed and consequently reduced demand for mixture, the velocity through passage I 9 under these circumstances -will be approximately. the same'as the velocity through this passage at wide open throttle. The smaller passage'is preferably beneath the larger so that the continuous flow of mixture through the smaller passage whenever the engine is running will keep this passage free of accumulations of unevaporized fuel.

Another reason for putting at the 'bottomV of the v` crank case` the inlet passage which is open at all i imes when the engine is running lies in the fact that the disk valve 30 has a better seal at the bot-V tom of the crank case thanis possible between valve 29 and the top/ of the crank case. gine shown is arranged upon a vertical axis so that'the weight of the crank shaft, y wheel and associated I"parts is carried by the crank case through the crank cheek and valve disk 30. The close t between disk 30 and the bottom of the crank case minimes leakage at this point and any. leakage which occurs past disk 29 will be ,unimportant for the reason that at low speeds 'the passage I8 is wholly cutoff by throttle valve 25 The en-l and at high speeds the slight amount of leakage which might occur would beunim'portant.

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 efIiciency. It will be obvious that by using additional valves and manifolds, a still further in crease could be made, each manifold being preferably cut olf in succession in order to approach a condition of substantially constant velocity through the several 'manifolds The, peculiar form of the central cheek is determined by its weight and the desirability of disposing that weight in a manner to counterbalance the loss oi weight in cheeks 29'and 30 occasioned by the provision of the segmental openings therein.

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

This application is a continuation in part of my application for Patent No. 1,932,521 granted October 31, 1933, and contains claimed 'subject matter divided therefrom.

1. In an internal combustion engine, the com-. bination with a. compression chamber provided `vance of the other during each cycle of engine operation, and a separate throttle valve means for controlling flow through at least one of said ports.

2; In an internal combustion engine, the combination with a crank shaft and a crank case lcompression chamber provided with admission ports, of means for varying the time in the engine cycle, of admission of gas through said ports, said means comprising valve mechanism operatively connected with the' crank shaft to be operated thereby in each crank shaft cycle for the successive closing of the respective ports,

and a separate throttle valve means for controlling gas admission through at least one of said ports.

3. In a two cycle internal combustion engine, the combination with a crank shaft and a crank case compression chamber provided with a plurality of mixture admission ports, of charge forming means for supplying mixture to said ports, and means for varying the portion of the engine cycle through which such mixture is supplied, said means comprising valve,l mechanism operatively connected with the crank shaft to be operated during each crank shaft cycle for the'successive opening and successive closing of the respective ports, and a separate throttle valve operatively disposed `to c'ontrol mixture flow through at least one of said ports independently of the other, whereby tov limit the total portion of the engine cycle through which mix-V ture is admitted to said crank case.

4. In a two cycle engine, the combination with a compression chamber provided with mixforming means for preparing mixture for delivery through said ports to said chamber, and

means for timing the portion of theengine cycle devoted to the admission of such mixture, said last mentioned means comprising crank shaft operated valve mechanism controlling the respective ports and timed to `open said ports successively,v and mechanism for progressively throttling said ports, said mechanism being operatively connected to throttle the port first opened before 'throttling the other by said valve means port.

5. In a two cycle engine, the combination with a compression chamber provided with mixe ture admission ports, of a crankshaft, charg .forming means for preparing mixture for delivery through said ports to said chamber, and means for timing the portion of the engine cycle devoted to the admission of such mixture, said last mentioned means comprising crank shaft operated valve mechanism controlling the respective ports and timed to open said ports successively', and mechanism for progressively throttling said ports, said mechanism being operatively connected to throttle the portflrst opened by said valve means before throttling the other port, the port rst throttled by saidI mechanism being of larger capacity than the port last throttled thereby.

6. A two cycle internal' combustion engine comprising the combination with an upright. crank shaft and a crank case provided with upper and lower ports, of disk valve elements m`ounted on said shaft and controllingthe respective ports and provided with openings for registration with said ports successively, whereby to maintain one of said ports open in advance o f the other,

charge formingv means for supplying mixture to the respective ports,'and a separate mechanism for successively throttling at least one of said 'i ports to substantially cut off the ow of mixture therethrough to said crank case, the said port throttled by said mechanism comprising the top port of' said crank case, whereby to accelerate lmixture flow through the lower port of said crank case while varying the total combined", period of port opening for timing the admission of mixture to the crank case.

7. In an internal combustion engine, the combination with a crank shaft, a mixing chamber and a mixture receivin'g chamber, of means for timing the portion of the crank shaft cycle devoted to communication between said chambers, said means comprising a plurality of passages -leadingfrom the mixing chamber to the receiving chamber, individual crank shaft actuated valves controlling saidv passages and timed to provide successive open periods for the'g respective passages, and,-throttle valve mechanism operatively arranged for the opening and closing of the pas-f sage having the first open 'period as determined by said crank shaft actuated valve means.

8. In an internal combustion engine, the' combination with a crank shaft, of a crank'case Z21:0,4515 ture admission ports, of a crank shaft, charge compression chamber provided with bearings for slid shaft and with ports opening into said crank case adjacent said bearings, and means for ad mitting mixture to the crank case through` said ports for varying portions of the crank shaft cycle, said means comprising crankdisks on said shaft constituting valve elements ported for controlling communication between said ports and said crank case, the ports of the crank disks and the ports of lthe crank case being so timed' as to ports, means for supplying mixture to the respective ports,` and throttle valveV means for successively opening and closing said ports and arranged to throttle the port having the first open 1 period substantially completely before materially throttling the port having the'last open period as determined by said crank shaft disks.

9. Inan internal combustion engine, the combination with av crank shaft having ported valve disks, of a crank case having bearings for said shaft and mixture admission ports with which the ports of said disks are arranged to register for the control of mixture admission to said crank case, thel positioning of said disks on said crank `shaft with respect to the ports in the crank case being such as to provide successive open periods for the crank case mixture admission ports durling each crank shaft cycle, and means lfo-r timing K mixture admission to the crank case comprising a single charge forming device provided with manifolds leading to the crank case ports, and a said1 manifolds in a direction to cut off flow through one of said ports'before materially affecting now through the other.

provide successive open periods for the respective single throttle valve movable successively across 10. In an internal combustion engine, the coni- I bination with a crank shaft having ported valve disks, of a crank case having bearings for said shaft and mixture admission ports with which the ports of said disks are arranged to register for the control of mixture 'admission to said crank case, the positioning of'said disks on said crank shaft with respect to the ports in the crank case. being such as to provide successive open periods for the crank case mixture admission ports during each crank shaft cycle, and means for timing mixture admission to the crank case comprising a single charge forming device provided with manifolds leading to the crank case ports, and a single throttle valve movable successively across said manifolds in a direction to cuty off flow through one of said ports before materially 'affecting flow through the other, said charge form- -ing device comprising a mixing chamber having an ',air admission aperture and having delivery .apertures registering with the vrespective manifolds, a jet projecting into themixing chamber betweensaid inlet and delivery apertures, and an imperforate wall opposedto said jet and provided with a pivotal mounting oppositesaid jet v upon which said wall is -movable across the successive delivery apertures.

' INNT. IRGENS.

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