US2425181A - Internal-combustion engine and attachment - Google Patents

Description

g- 1947- E. M. Fl'SK INTERNAL-COMBUSTION ENGINE AND ATTACHMENT Filed March 6, 1945 2 Sheets-Sheet 1 mwznrox BY Edw/h MFIIs'k ATTORNEY E. M. FISK INTERNAL-COMBUSTIO ENGINE 'AND ATTACHMENT Aug. 5, "1947.

Filed Match 6', 1945 2 Sheets-Sheet 2 Patented Aug. 5, 1947' UNITED STATES PATENT orrica INTEBNAL-CODIBUSTION ENGINE AND Y ATTACHMENT Edwin M. Fisk, Los Angcles, Calii., assignor of one-half to James H. Reid, Steiner A. Larsen,

and Roy E. Binkert, copartners, doing business 1 as Reid Manufacturing Company, Los Angeles,

Calif.

Application March 6, 1945, Serial No. 581,206

80laims.

My invention primarily lies in an attachment to control the exhaust cycle of a two-cycle engine, either of the Diesel type or any other twocycleinternal combustion engine.

However, it is to be understood that my invention may .be built into a two-cycle engine at the time of its manufacture so that it may [be an integral part thereof, instead of what isusually termed merely an "attachment."

An object of the invention is to provide means in a two-cycle engine to close the exhaust port at or near bottom dead center and to keep some closed until the piston covers the exhaust port, in order to increase the effectiveness of the compression stroke of the engine.

Another object is to provide means to stop the outward flow of air from the cylinder while the intake ports are open. I

My invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises'novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawings merely show and the following description merely:- describes one embodiment of the present invention, which is given by way of illustration or example only.

In the drawings, like reference characters designate similar parts in the several views.

Fig. 1 is a vertical, broken section of an internal combustion engine embodying my present invention, showingthe valve in a closed position.

Fig. 2 is a view similar to Fig. l, but showing the valve in an open position.

Fig. 3 is a sect-ion taken on the line 3-3 of Fig. 2, looking in the direction of the arrows.

Fig. 4 is a broken, horizontal section, taken on the line 44 of Fig. 2.

Fig. 5 is a preferred firing diagram of my present embodiment.

Referring more in detail to, the drawings, the reference number 8 indicates the cylinder of an internal combustion engine which is provided with intake ports 9 and exhaust ports l0. Suitable cooling means may be provided for the engine. Cooling fins l2 are merely shown as one type of cooling means. It is believed clear to those skilled in the art without further illustration that conventional water cooling means may be employed.

A piston is shown at l3 arranged to operate a connecting rod l4, which in turn operates a crankshaft shown in part at It. The piston has suitable rings ll. The'crankshaft is also of conventional construction and further illustration is, therefore, not-believed necessary to those skilled in the art. Sufllce to say, ball bearings l8 support the crankshaft by means of race members l1 and I3. A bushing l9 also Journals the crankshaft in a crankcase bearing 20.

A cam 2| bears against the side of the inner race member l8 and is held to rotate therewith by means of a nut 22 screwed upon the crankshaft IS. The circumference of the nut 22 is notched (as best shown in Fig. 3) to receive a tool for its manipulation. A cam follower wheel or roller 23 rides on the periphery of the cam 2|.

A reciprocable .body 24 carries the wheel or roller 23 and also carries a valve stem 25. The body member 24 and the valve stem 25 have an adjustable connection 26 in order to adjust a valve 21 on the stem 25. The valve 21 is movable to (a) a position (shown in Fig. 1) in which it fits in and closes an exhaust outletpassage 23, and (b) a position (shown in Fig. 2) in which it rests on a seat 30, thereby permitting a chamber 3| to connect the exhaust passage 29 with the exhaust ports Ill around a bracing member 32.

The body member 24 reciprocates in a bushing 33, while the valve sierra-25 operates in aesleeve 34 mounted on the under side of the valve seat 30. A coil spring 35 abuts against the under side of the seat and against a washer 36 fixed upon the stem 25. The spring tends to move the valve to a. non-obstructing position with regard to the chamber 3|, to-wit, on the seat 30. Telescoping housing members 31 and 38 enclose th spring and valve stem.

The crankcase 39 houses the cam 2|. The cam has a rather abrupt rise 40 to close the valve 21 quickly when it is desired. Then there is a gradual recession 4| of the cam .back to its lowest point to permit the spring to keep the roller 23 in contact with the cam periphery at all times without making the spring unduly strong.

Clamping bolts 42 are arranged to fasten the walls 43 of the chamber 3| to the body of the engine. Tapering edges 44 of the walls 43 provide a tight engagement with the body of the engine when the bolts 42 are drawn-tight. A

. bolt Ell in an opening in the brace 32 serves to hold the cylinder and crankcase together in the manner of the stud 31 in my Patent No. 2,334,185,

chamber 45 (above the piston l3 inFigs. 1 and 2) is checked, to-wit, by the closed valve 21, as-

shown in Fig. 1, while the piston is on its upward or intake stroke. The valve 21 is open substantially throughout the driving or downstroke of the piston and closes at or near the bottom dead center. Fig. 1 shows the piston on its upstroke, while Fig. 2 shows the piston on its downstroke. The piston is about ready to begin its upstroke in Fig. 2, and the cam is about ready to close the valve in the latter figure. The valve 21 remains in its closed position until the piston l3 covers the exhaust ports 10. Then the valve 21 is opened to permit the exhaust of gases of combustion through the ports l0, through the chamber 3| and through the exhaust outlet passage 29, as the piston uncovers the exhaust ports in the downstroke of the piston.

Fig. 5 illustrates a preferred sequence of steps in the operation of my present construction. Beginning at 50, at the top dead center (T. D. C.), the expansion, combustion or downstroke takes place for approximately 110 of the cycle. The exhaust opens (E. O.) at 5|. Then from that point 5| down to point 52, about 28 farther on, only the exhaust ports are,open for the escape connected to control the passage of gases through the exhaust port, spring means to move the valve means to open position, and means on and controllable by the crankshaft to close the valve means against the spring means substantially prior to the closing of the intake port, to permit intake or fuel for a period without simultaneously exhausting gases from the cylinder.

2. In a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports of different dimensions and the bottom of said ports being in the same transverse plane, a piston of gases of combustion. Then from point 52 to point 53, both the intake and exhaust ports are open, thereby producing a scavening effect for approximately 42.

'I'hereupon, the exhaust closes (E. C.), that is, the exhaust valve 21 closes. Of course, the piston does not close the exhaust ports, for the piston is at or near thebottom dead center of its stroke. After the exhaust valve closes, the intake ports 9 are, of course, still open, so that an intake and/or super-charge of air is taken into the combustion chamber for approximately 42". At this point the piston covers the intake ports, and the valve 21 remains closed until the piston covers the exhaust ports also. Then the valve 21 opens. From the point 54, wherethe intake is closed, until the piston reaches. approximately top dead center, compression continues for about 138. Of course, combustion then takes. place,'and a new cycle of operation is begun.

It is'believed clear without further illustration thatother types of valves may be used, other than that shown and described.

It is believed clear without further illustration,

' that other types of valves, other than that shown and described herein at 21, and its actuating mechanism, may be employed. That is to say, other types of valves, such as a butterfly, slide or rotary valve might be used in lieu thereof.

While I have illustrated and described what I now regard as the preferred embodiment of my invention, the construction is, of course, subject to modifications without departing from the spirit and scope of my invention. I, therefore, do not wish to restrict myself to the particular form p of construction illustrated and described, but desire to avail myself 01 all modifications that may fall within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is: 1. In a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports, a piston mounted to reciprocate in the cylinder to cover and uncover the ports in compression and expansion strokes, the exhaust port in the cylinder being positioned to be opened ahead of the intake port in the expansion stroke of the piston,

mounted to reciprocate in the cylinder to cover and uncover the ports in compression and expansion strokes, valve means connected to control the passage of gases through the exhaust port, a crankshaft operable by the piston, spring means tending to move the valve means to. one of its operative positions, and means connected to be operated by the crankshaft and arranged to actuate the valve means to its opposite position against the action of the spring means, said crankshaft operated means being connected to close the valve means controlling the exhaust port prior to closing the intake port in the compression stroke of the piston.

3. In a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports, a piston mounted to reciprocate in the cylinder to cover and uncover the ports in compression and expansion strokes, an exhaust conduit connected with the exhaust port, valve means connected to control the passage of exhaust gases through the said conduit, a'crankshaft operable by said piston, spring means tending to move the valve means to one of its operative positions, and means connected to be operated'by the crankshaft and arranged to actuate the valve means to its opposite position against the action of the spring means, the spring means being connected to open the valve means at least by the time the piston uncovers the intake port in the expansion stroke and the crankshaft operated means being connected to close the valve means substantially prior to closing the intake port in the compression stroke.

4. In a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports arranged at least partially in the same transverse plane, a piston mounted to reciprocate in the cylinder and to cover and uncover the ports, valvemeans connected to control the passage of gases through the exhaust port, and cam means connected to be operated by the piston and arranged to close the valve substantially concurrently with the upstroke of the piston and to hold it closed until the piston covers the exhaust ports, and prior to closing the intake port by reciprocation of the piston, and spring means to open said valve when said piston has covered the exhaust ports.

5. In a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports arranged at least partially in the same transverse plane, a piston mounted to reciprocate in the cylinder to cover and uncover the ports in compression and expansion strokes, an exhaust conduit connecting with the exhaust port, valve means operable to control the passage of exhaust gases through said conduit, acrankshaftoperable by the piston, and valve-controlling mechanism comprising spring means tending to move the valve means to one of its operative positions and cam means connected to be actuated by the crankshaft and to operate the valve means to its d opposite position against the action of the spring means, said mechanism being adjusted toclose the exhaust passage substantially prior to closing the intake port by reciprocation of the piston.

6. In an attachment for a two-cycle, internal combustion engine, a cylinder having intake and exhaust ports and having a piston reciprocable to cover and uncover the ports: a conduit to connect with the exhaust port, a valve in said conduit, a spring to open and hold said valve open during the downstroke of the piston and means arranged to be connected to be operated by the upstroke of the piston to close the valve and hold same closed until the piston covers the ports in said cylinder. y g

'7. In an attachment for a two-cycle, internal combustion engine having intake and exhaust ports at least partially in the same transverse plane and having a piston reciprocable to cover and uncover the ports and connected to drive a crankshaft: an exhaust conduit to connect with the exhaust port of the cylinder, valve means opanswer combustion engine, a cylinder having intake and exhaust ports at least partially in the same transverse plane and having a piston reciprocable in said cylinder to cover and uncover the ports and connected to drive a crankshaft; a conduit connected to the exhaust ports of the cylinder, a

valve in said conduit to control the passage of exhaust gases therethrough, a spring to hold the valve open during the downstroke of the piston past the ports in the cylinder, and a cam connected to and operable by the crankshaft to move said valve to closing position during the upstroke or the piston past the ports in said cylinder and prior to closing the intake ports.

- EDWIN 'M. FISK.

'rue of this patent:

UNITED STATES PATENTS

Images