US1921510A - Two-stroke cycle internal combustion engine - Google Patents

Description

ug. 8, 1933. W. DE wAsMuNDT L92L510 TWO-STROKE CYCLEIINTERNAL COMBUSTION ENGINE Filed July 21, 1930 2 sheets-sheet 1 Aug. 8, 11933@ w. DE WASMUNDT TWO-STROKE CYCLE INTERNAL COMBUSTION ENGINE Filed July 21, 195o 2 Sheets-Sheet 2 Figi;

y? M. a, Nmv/v M y@ Patented Aug. 8, 1933 UNITED STATES TWO-STROKE CYCLE INTERNAL COMBUSTION ENGINE Wladimir De Wasmundt, Paris, Francev Application July 21, 1980, Serial No. 469,492, and in France August 5, 1929 4 Claims.

Two-stroke cycle internal combustion engines have in general the disadvantage of allowing a considerable quantity of fuel to be lost, which escapes during the scavenging through the exhaust ports. Their filling with a mixture of gas and air is frequently defective and the carburetors themselves defectively pulverize the fuel which tends to condense in the more or less long passages, especially in those of multi-cylinders.

The present invention has for its subject a device eliminating these disadvantages and characterized in that the cylinders are coupled in pairs, the movements of the pistons being in opposition, and in that the high pressure, which exists in a cylinder after explosion or compression, between the high dead point and the midstroke of the piston, is used to produce a stream of air which draws the fuel into the other cylinder. The fuel rises when there is no pressure in one of the cylinders, whilst the piston of the other cylinder closes the tube connecting together these two cylinders.

The following description and the accompanying figures indicate by way of example various methods of carrying the invention into effect.

Figure 1 is a diagrammatic view of the assemblage of two coupled cylinders.

Figures 2, 3 and 4 are diagrams adapted to assist in the understanding of the operation.

Figure 5 shows an arrangement of a tube for supplying the fuel into the cylinder, and

Figure' 6 shows a section by way of example `of .a form of construction of a pulverizing injector.

The coupled cylinders 1 and 2 (Figure 1) have their pistons 3 and 4 connected by rods, not illustrated, to cranks arranged at 180 in such a manner that one of these pistons is at the top of its stroke, whilst the other is at the bottom.

The cylinders 1 and 2 are connected together by the tube or conduit 5 leading into each of the cylinders between the high dead point and the mid stroke. At the middle the tube is provided with a U-shaped portion in which the fuel is contained. This tube isprovided with one or more non-return valves such as 20 by which it communicates with a constant level chamber or with a low pressure supply pump. In the bottom of the cylinders are provided exhaust pipes 7 and 8 and pipes l1 and 12 leading into the crank U case and serving for the supply of fresh air which has been previously compressed in the crank case. Ports 9 and 10 enable pureair to be drawn into the crank case. `As there is no channel these ports may be as large as desired which enables complete filling of the cylinders at all speeds.

The operation will be readily understood by reference to Figures 2, 3 and 4.

In the phase illustrated in Figure 2 the piston 3 is at the top of its stroke, closing the tube 5. The explosion is produced behind the piston. 6 0 The piston 4 is at the bottom of its stroke, it uncovers the ports 8 and 11 thus permitting exhaust from the cylinder 2, scavenging by pure air and refilling of the cylinder.

The stroke continuing (Figure 3) the piston 65 4 closes the ports 8 and 11 and thus makes the cylinder 2 a closed space.

The piston 3 uncovers the end of the tube 5. The gases of combustion which are at a high pressure behind the piston 3 pass rapidly through 70 the tube 5 into the cylinder 2 drawing with them fuel from the pulverizing injector 6 and finely pulverize the-fuel.

The movement of the engine. continuing the piston 4 reaches the top of its stroke (Figure 4) 75 having compressed the mixture of air and fuel,

the piston 3 reaching the bottom of its stroke, exposing the ports 'l and 12 and the cycle of operations recommences.

For ensuring better whirling it is possible as shown in Figure 5 to cause the `tube 5 to lead. into the cylinders tangentially by directing it at the same time, if desired towards the cylinder head which is the hottest portion.

Figure 6 shows a method of construction of 85 a pulverizing injector in which the pressure producing the drawing in of the fuel into one of the cylinders serves at the same time-to facilitate the operation of the jet.

For this purpose the tube 5 is provided at the 90 middle portion with a restriction 13 adjustable by means of a screw 14. The fuel which comes from a constant level chamber, or is supplied by a low pressure pump, after having passed through the valve 15, enter the U-shaped tube of which the branches 16 and 1'7 extend from each side of the restriction 13 by jets 18 and 19.

The operation will be readily understood.

If a stream of air is produced from right to left, the pressure, by reason of the loss of velocity due to the restriction, will be larger at the right at 18 than on the left at 19. ,The pressure in branch 16 will then cause fuel torise into branch 17 until it traverses jet 19 and is pulverized. 105

The filling of the tube 5 is effected in the following manner:

When the pressure in the cylinder 1 falls, for example to atmospheric pressure, the tube 5 closed at its other end by the piston 4 is lled 110 automatically with fuel which enters therein through the valve 20, either by the action of gravity or under pressure if a low pressure pump is used. The quantity of gas under pressure necessary for conveying the fuel may be adjusted by suitably calibrating the tube 5 or the constriction 13 or by' means of a needle valve or the like. It also depends upon the point at which the tube enters the cylinder.

' It may be mentioned that the injection is effected after the closing of all the ports without moving members and consequently without wear. The scavenging may be extremely complete as there is no fear of losing fuel through 'exhaust orifices. The consumption of fuel per horse power hour is at the most equal to a four-stroke cycle engine as there is noloss of fuel throughexhaust ports or leakage produced by feeding in strokes. It is even less as condensation is zero and the pulverization is better.

The tube 5 is always traversed by gases at a high temperature, it is therefore always very hot which is favourable to the pulverization of the fuel and does not interfere with the fillingA of the cylinder. This, therefore, permits of the use of heavy oil.

I claim:-

l. In combination with an internal combustion engine provided with a pair of cylinders, a pair of pistons mounted to reciprocate in said cylinders out of phase with one another, means for discharging burnt gases from said cylinders and means for supplying air thereto,-a fuel injecting assembly comprising a lconduit communicating at opposite extremities with said cylinders, said conduit having a restricted portion formed 2. A structure as defined in claim 1 and in combination with means operative to change the effective section of the restricted portionof said first named conduit.

3. In combination with an internal combustion engine provided with a pair of cylinders, a pair of-pistons mounted to reciprocate in said cylinders out of phase with one another, means for supplying air to the said cylinders and means for discharging burnt gases from said cylinders,- a fuel injecting assembly comprising a conduit communicating at opposite extremities with said cylinders, said conduit having a restricted portion formed at a point intermediate the extremities thereof, a fuel supply conduit provided with at least two branches communicating with said first named conduit at points on opposite sides of the restricted portion of thel latter, and means for supplying fuel to said fuel supply conduit, whereby differences in pressure due to the ficw of gases through said first named conduit from one cylinder into the other under the action of said pistons will cause fuel to fiow alternatively into said cylinders in thedirection oi movement of said gases.

4. A structure as defined in claim 3, in combinationwith a pair oi jets mounted 'at the points where the branches of said fuel supply conduit communicate with said first named conduit.

WLADIMIR DE WASMUNDT.

Images