US2747557A

US2747557A - Diesel engines

Info

Publication number: US2747557A
Application number: US390858A
Authority: US
Inventors: William J Silva
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-11-09
Filing date: 1953-11-09
Publication date: 1956-05-29
Anticipated expiration: 1973-05-29

Description

W. J. SILVA DIESEL ENGINES May 29, 1956 3 Sheets-Sheet 1 Filed NOV. 9, 1953 ATTORNEYS.

May 29, 1956 w. J. SILVA 2,747,557

' DIESEL ENGINES Filed Nov. 9. 1953 s Sheets-Sheet 2 INVENT OR i l Fliz'a'm JSZZ a BY @M ATTORNEYS United States Patent DIESEL ENGINES William J. Silva, New Orleans, La.

Application November 9, 1953, Serial No. 390,853

6 Claims. (Cl. 12332) This invention relates to internal combustion engines of the diesel type and more particularly to a two-cycle diesel engine.

The principal object of the invention is to provide an improved diesel engine which will be more simple, more compact and lighter than prior diesel engines of comparable horse power.

A further object is to provide an improved diesel engine which will eliminate the customary cam shaft, timing gears, valves, rocker arms and push rods.

A still further object is to provide the crank shaft, rather than a separate cam shaft, with the necessary cams for operating the fuel injectors.

Another object is to provide an improved diesel engine which will operate to equal advantage in either direction, primarily for marine use.

Another object of the invention is to provide the crank shaft with two sets of injector operating cams, one set being operable when the engine is driven in one direction and the other set being operable when the engine is driven in the other direction, one set or the other being automatically brought into operation according to the direction in which the engine is started.

Yet another object of the invention is to provide a sleeve carrying both sets of cams and shiftable axially to bring one set or the other into position for operation, A

the sleeve being threaded on an extension of the crank shaft and being axially shifted by the screw threads in one direction or the other, according to the direction in which the engine is turned over to effect starting.

A still further object of the invention is to provide a novel scavenging blower for the engine cylinders which will operate to equal advantage regardless of the direction in which the engine is driven.

With the above and other objects in view that will become apparent as the nature of the invention is better understood, the same consists in the novel form, con1- bination and arrangement of parts hereinafter more fully described, shown in the accompanying drawings, and claimed.

In the drawings:

Fig. l is a longitudinal sectional view through the improved engine;

Fig. 2 is a transverse sectional view on line 22 of Fig. 1, the blower being shown principally in elevation;

Fig. 3 is an enlarged vertical sectional view showing the blower; and

Fig. 4 is an enlarged side elevation partly in section showing the cam sleeve and associated parts.

A four-cylinder engine is shown but the invention is equally adaptable to a six or eight cylinder construction. The four cylinders are denoted by the numerals 1, 2, 3, and 4, with cylinder 1 at the flywheel end of the engine. These cylinders are within a block 5 and a head 6 is secured to said block. This head carries fuel injection spray nozzles 7 but no valves nor valve actuating rockers.

The pistons of the four cylinders are denoted at 8 and their connecting rods at 9. These rods are connected to "ice the four crank pins 10 of the crank shaft 11, and said crank pins are spaced apart 90. In Fig. 1, the pin 10 under cylinder 1 is at upper dead center, the pin under cylinder 4 is at lower dead center, the pin under cylinder 2 is behind the crank shaft axis, and the pin under cylinder 3 is in front of said axis. With this 90 crank pin spacing, the firing order of the cylinders is 134-2.

The crank shaft 11 is mounted in main bearings 12 in a suitable crank case 13, one end 13 of said crank case being extended beyond the block 5 and having a bearing 14 aligned with the main bearings 12. One end 15 of a crank shaft extension 16 passes through this bearing and is provided with a pulley 17 for driving a generator and water pump. The other end of the extension16 is provided with a flange 18 bolted at 19 to a flange 20 on one end of the crank shaft body, said extension 16 thus forming virtually a part of the crank shaft. The other end of this crank shaft has a flywheel 21 and said flywheel carries the usual ring gear 22 for starting purposes. Two starters are preferably used, one to start in one direction and the other to start in the other direction. These starters are indicated in Fig. 2 by the broken lines 23.

On the crank shaft extension 16, there is a cam sleeve 24 for actuating injector pumps 25 from which fuel lines 26 extend to the fuel injection spray nozzles 7. The pumps 25 are fed by a transfer pump 27. All of the

pumps

25 and 27 are mounted on the top plate 28 of the crank case extension 13 and said pumps include

plungers

25 and 27*, respectively. These plungers are camactuated and spring-returned. The cam for the transfer pump 27 is on the end 15 of the crank shaft extension 16 and is denoted at 29, said cam being on a flange 30 of said end 15. The cams for the injector pumps 25 are on the cam sleeve 24 and will be later described.

The crank shaft extension 16 is provided with a coarse screw thread 31 and the cam sleeve 24 has an internal thread 32 engaging said thread 31 as illustrated in Fig. 4. This cam sleeve is axially shiftable from the position shown, against flange 30, to a position against flange 18 and the shifting of said sleeve is eflected by the coacting screw threads 31, 32 according to the direction in which the crank shaft is initially rotated to start the engine. During such initial crank shaft rotation, the cam sleeve 24 is held against turning with the crank shaft by the resistance of the various pumps and consequently said sleeve will be axially shifted to the limit allowed by the flange 18 or 30 as the case may be. As soon as the sleeve abuts either of these stop flanges 18, 30, said sleeve rotates bodilywith the crank shaft 11 and operates the transfer pump 27 and the injector pumps 25, with the result that the engine will start firing and continue to operate, the cylinder being scavenged and supplied with air by means yet to be described.

The flange 18 and adjacent end of the cam sleeve 24 preferably have teeth 18 to mesh when said flange 18 and said cam sleeve abut. Similarly the flange 30 and adjacent end of the sleeve 24, preferably have teeth 30 for the same purpose. The teeth 18 or 36* drive the sleeve 24 and prevent the screw threads 31, 32 from tightly jamming said sleeve against either flange.

The cam sleeve 24 has four peripheral zones 1*, 2 3 4 allotted to the cylinders 1, 2, 3, 4, respectively. For better understanding, those zones have been defined by dot-and-dash lines. The zone 1 has one cam 1 which operates the injector pump for cylinder 1 for left hand operation of the engine, as indicated by the arrows in Figs. 1 and 4. This zone 1 also has a cam 1 for operating the injector pump of cylinder 1 for right hand operation of the engine. These two cams 1 and 1 are spaced apart and are offset longitudinally of the sleeve 24 to allow only cam 1 to operate the injector pump when said sleeve 24 occupies one position as in Figs.

V ence of the rotor 43.

'Two air inlet passages 46 and 47 extend from the air 7' 3 V l and 4 and to allow only the cam 1 to operate said injector pump when said sleeve is shifted to its other 7 position.

' positioned'as described in connection with the cams 1 and 1 of zone 1 The cams 1 2 3 and 4 are of course spaced 90 apart and the .same is true of the cams 1, 2,3, and

With the various cams in the positions shown, the engine is turning to the left (as viewed from the flywheel end). The piston of cylinder 1 is on top dead center and thencam 1 is. operating the injector pump of said cylinder 1 to fire it. Cyl'inder 2 has just fired and the injector pump cam 2 allotted to this cylinder 2 is ninety degrees past dead center. The piston'of cylinder 3 is ascending on its compression stroke and the cam 3 is 90 before top dead center. Cylinder 4 is exhausting and the corresponding cam 4 is 180 before top dead center.

Each of the cylinders is provided with a piston-controlled exhaust port 33 as shown in Fig. 2 and with an air admission port 34. Air is supplied tothe cylinders through the ports 34 by means of a blower 35 which is driven by a silent-chain-and-sprocket drive 36 from the crankshaft. Just after any piston uncovers the exhaust port 33 and permits exhaust gases to escape, the piston uncovers the air admission port 34 and the blower 35 forces scavenging air into and across the cylinder. As the piston ascends and covers the

ports

33 and 34, it compresses air in readiness for injection of fuel and when this injection occurs the cylinder fires.

The blower 15 may be of any type which will operate regardless of the direction in which it is driven, but this characteristic is essential unless complicated and expensive blower reversing means is provided, as said blower will be driven in one direction during left hand rotation of the engine and reversely during right hand rotation.

The preferred blower construction is shownin Fig. 3. A casing 37 is provided having an air inlet 38 and in the casing 37 and coa'cts with about half the circum- V fer'ence of rotor 42'. A second substantially semi-circular wall 45 similarly coacts with about half the circumferinlet'38 past the ends of the wall 44- to conduct air to the; rotors regardless of .the direction in which they rotate.

Only one of these passages 46, 47 functions during right hand rotation and only the other during left hand rotation/These two passages 46 and 47 have check valves 7 46 and 47 respectively, .to insure this, both of these valves being of suction-opened and pressure-closed form.

this, both'of said valves 48 and '49? being of pressureopened and suction-closed form. v

In Fig. 3, the suction created by the rotating rotors 4 2, 43 'at the intake side of the-blower 35 is holding.

check valve 46 closed. At the same time, the pressure created by the rotors at the output side of the blower is holding the check valve 47 closed and the valve 49*- open. Consequently, with the rotors turning as indi cated by the arrows thereon, theair will flow as indicated by the other arrows. When the engine is reversely driven, however, and the rotors consequently turn in the other direction, the valve 47 opens and valve 46 closes, causing the air inlet passage 47 to function. At the same time, valve 48 opens and valve 49 'closes, causing the air discharge passage 48 to function. Thus, the blower will operate to perform its functions whether the engine be turning in one direction or the other.

It will be seen from the foregoing that a novel construction has been providedv for attaining thedesired ends, but it is to be understood that. variations may well be made. For example while a reversible engine has been shown requiring two sets of cams, it will be clear that for an engine to rotate only in one direction, only one set of cams would be required. In that case, a cam member corresponding. to sleeve 24 would be directly near said crank shaft, tubes connecting said injector pumps' withsaid injector spray nozzles respectively, a cam sleeve surrounding a portion of said crank shaft, said cam sleeve having one set of cams for operating said'injector pumps when the engine is to rotate to the right, said cam sleeve having a second set of cams for operating said injector pumps when the engine is to rotate to the left, said sleeve being axially shiftable in response to drag forces when the crankshaft is turned over for starting in one direction to one position in which said one set of cams becomes effective and being axially shiftable in response to dragforces when the crank shaft is turned over for starting in the other direction to a second position in which said second set of cams becomes effective, stop means for limiting the axial movement of said sleeve when it reaches either of said positions. 7

2. A structure as spccifiedin claim l, saidsleeve having a threaded connection with said crank-shaft between said stop means.v

3. A structure as specified in claim 1, said sleeve having a threaded connection with said portion of said crankshaft between said stop means, said stop means comprising stop shoulders on said portion of said crankshaft to be struck by the ends of said sleeve. 7

4. A structure asspecifiedin claim 1, said sleeve having a threaded connection with said portion of said crankshaft between said stop means, said stop means comprising stop shoulders on said portion of. said crank shaft to be struck by the ends of said sleeve, said step shoulders and sleeve ends having coacting sleeve driving teeth.

5. A structure as specified in claim 1, said blower being of a type which will function regardless of the, direction in which'said blower is driven.

6. A structure as specified in claim 1', said blower comprising a casing having an air inlet and an air outlet, two

'coacting rotors in" said casing, said rotors having intermeshing lobes, one substantially semicircular wall in said casing and engaging the periphery of one of said rotors, a second substantially semi-circular wall in said casing and engaging the periphery of the otherrotor, the ends of said one wall being spaced from the ends of said second wall, 7

two air inlet passages extending from said air inlet to the ends of said one wall, respectively, two air discharge passages extending from the ends of said second wall respectively to said air outlet, two suction opened pressureclosed check valves for said two air inlet passages respectively, and two pressure-opened suction-closed check valves for said two air discharge valves respectively whereby the blower will receive air from said air inlet and discharge air through said air outlet regardless of the 5 direction in which said rotors are driven.

References Cited in the file of this patent UNITED STATES PATENTS 354,063 Johnson Dec. 7, 1886 10 6 Lepley Mar. 11, 1919 Pielstick Apr. 1, 1930 Gosslau Oct. 10, 1933 Martin et al Mar. 20, 1934 Reiland Nov. 28, 1944 Yingling Jan. 29, 1946 Froehlich Feb. 5, 1946 FOREIGN PATENTS Italy Jan. 23, 1939