US2449262A

US2449262A - Valve arrangement for external-combustion engines

Info

Publication number: US2449262A
Application number: US474671A
Authority: US
Inventors: Weigel Daniel Michel
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-02-04
Filing date: 1943-02-04
Publication date: 1948-09-14
Anticipated expiration: 1965-09-14

Description

Sept 14 1943- D. M. wElGEl. 2,449,262

VLVE ARRANGEMENT FOR EXTERNAL-COMBUSTION ENGINES "UBLJV Wm D. M. WEIGEL `VALVE ARRANGEMENT FOR EXTERNAL-COMBUSTION ENGINES Filed Feb. 4, 1943 2 sheds-sheet 2 INVENTOIL .DAN/EY4 M- WFE WM im wmv A rromvEYs Patented Sept. 14,' 11948 UNITED STATES PATENT OFFICE VALVE ARRANGEMENT FOR EXTERNAL- COMBUS'VIION ENGINES Daniel Michel' Weigel, Detroit, Mich.

Application February 4, 1943, semi No. 474,611

' 8 Claims.

This invention relates to external combustion engines and particularly to an improved injection type engine.

The principal objects of the present invention are to incorporate in an injection engine operating on a constant volume combustion cycle, such as that disclosed'in my Patent No. 2,364,330, issued December 5, 1944, a greater exibility and wider range of compression pressures without substantial increase in size or numberV of parts of the eng-ine; to provide an improved and sim-` plied valve arrangement in which a single sleeve valve controls communication of a combustion chamber with an intercooler and a power cylinder, and also controls inlet;v and outlet valves for each of two separate compression cylinders; and to provide means to vary the 4amount ofair admitted from an intercooler to a combustion chamber in accordance with the opening of a throttle valve on the intake of a compression cylinder supplying compressed air to the intercooler, so that the fuel injector pump and the air throttle may be directly coupled and varying quan# titles of air and fuel in substantially constant proportions may be admitted tothe combustion chamber depending upon the position of thel throttle control.

Other objects and advantages will appear from the following detailed description of the preferred embodiment of the invention.

Referring to the drawings:

Fifi. 1 is a vertical sectional view of o ne cyl'- inder of an external combustion engine constructed according to the present invention;

Fig. 2 is an end view of the same; and

Fig. 3 is an enlarged sectional view of a fuel injector pump with a diagrammatic showing of the fuel piping. y

The engine illustrated'includes a cylinder block 5 having a crankcase 6 secured to one end and supporting a crankshaft 1. A cylinder 8 is formed in the cylinder block and surrounded by alwater jacket B. The upper end of the cylinder is c'osed by a head IIl having a depending Water jacketed portion II extending into the cylinder, and the lower end is closedby a cover I2.

A valve sleeve I3 is slidably mounted within the cylinder 8 and extends at its-upper end into the space between the cylinder 8 and the depending portion Il of the head. .The cylinder cover I2 is formed with a depending skirt portion Il which is bolted at I5 to an annular flange I6 depending from the cylinder block. The ilange I6 is slotted as shown at I1 and the 'lower end of the sleeve I3 is formed with a laterally proiectmg lug is which works ni the not. |11. 'rire sleeve I3 slidably bears on the inner surface 'of the cylinder 8 and on the outer surface of the cylinder cover I2 and its skirt I4. l 'l A piston I9 provided with suitable packing rings slidably bearsV within the sleeve I3 and 5 formed as an auxiliary piston so as to bear y throughout its circumference on the inner surface ofthe skirt I4 of the cylinder cover I2.. A

connecting rod 23 is journall'ed on a suitable wrist pin 24 carried by the cross head 22 and at its other end is journalled to a crank pin 25 of the crankshaft 1.

A suitable cam shaft 26 is arranged to be ydriven bythe crankshaft'l at a one-to-one ratio, as for example by a gear 21 on the crankshaft 1. an intermediate gear 28 and a gear 22 on the cam shlaft 28. The camshaft 2B is formed with a crank =pin 30 to which is journ-alled a connecting rod 3| which has its other end pivotally connectedto the lugr I8 projecting from the lower end of the sleeve I3. The crank pin 20 is arranged so as to reach its upper dead center about ahead of the crank pin 25.

A poppet valve 32 opens through the center of the cylinder head I0 and its depending extension I I. A suitable exhaust passage 33 is formed in the head and is arranged to be opened to the interior of the, cylinder '8 when the poppet Valve 32 is open.I The valve 32 is operated by a sultable rocker arm `and* push rod actuated by a cam 34 on the cam shaft 26;

A combustion chamber 35 is formed" in` the cylinder block adjacent the upper end of the cyl'. inder 8. A port'36 is cutthrough thesleeve Il and is arranged to open the combustion chamber 35 to the interior of the cylinder 8 in one position of thesleeve I3. Similarly a port 311s arranged to open communication between the combustion chamber 35 and a vpassage 138 in one position of the sleeve I3. Preferably the` combustion chamber is closed at its upper end by a plug 39 removably threaded linto the cylinder block, as indicated at 40.

At its lower end the sleeve la is provided with -port openings Il arranged to open communication between the interior of the 4cylinder on the under side of the piston I9 and an air intake estates passage d, which may be formed as illustrated to partially or completely surround the cylinder. Another port t3 formed in the sleeve i3 is arranged tovopen communication between an outlet passage 44 formedin the cylinder cover I2 and a passage 45 leading to an intercooler f 45. Thus the under side of the piston I9 is arranged to inspire air through the intake passage 42 and compress the same through the passages 44 and 45 into the intercooler 46.

Below the cylinder cover I2 the sleeve I3 is provided with a port 41 arranged to open communication between another inlet passage 48 and the interior of the skirt I4 above the cross-head 22. A port 45 formed in the sleeve valve is arranged to open communication between the interior of the sleeve I4 and a passage 55 which also leads to the intercooler 45.

The various ports in the sleeve valve I3 are arranged so that as the piston starts on its downward stroke from the position illustrated in Fig. 1 the port 36 opens the combustion chamber 35 to the interior of the cylinder 5, the port 43 opens the interior of the cylinder 5 below the piston I5 to the passage 45 leading to the intercooler and the port 41 opens the space between the crosshead 22 and the cylinder cover I2 to the intake passage 45. These ports remain open substantially throughout the downward stroke of the piston I5. or in other words remain open during the lower half of the reciprocation of the sleeve I3. As the crank pin 25 passes its lower dead center the crank pin 35, whichv is leading the crank pin 25 by about 90, moves the sleeve I3 into the upper half of its reciprocation. This movement of the sleeve I3 closes the ports 36, 43 and 41 and opens the ports 4I and 45 so as to establish communication between the intake passage 42 andthe interior of the cylinder 5 on the under side of the piston I3 and also to establish communication between the passage 55 leading to the intercooler 46 and the space between the cross head 22 and the cylinder cover I2.

The port 31 in the sleeve valve I3 is arranged to open the passage 36 in the cylinder head to the combustion chamber for a short period during the upper half of the stroke of the sleeve I3 after theport 36 has closed the combustion chamber from the interior of the cylinder head.'

This occurs during the upward stroke of the piston, beginning, for example, about 45 after bottom center and ending about 45 before top center. Thus communication between the combustion chamber and the passage 35 is again closed by the sleeve before the port 35 again opens the combustion chamber to the interior of the cylinder 5 on the downward stroke of the sleeve.

The intercooler 46 may consist, as illustrated. of a casing 5I which encloses a plurality of water tubes 52 communicating at one end with a water inlet 53 and at the other end with a water outlet 54, The air passages 45 and 55 lead through

feather valves

55 and 56 respectively into the interior of the casing 5I so that the air passes around the tubes 52. v

The opposite end of the intercooler 45 opens into an air passage 51 which communicates with the passage 35 in thecylinder head through the pressure 4regulating valve 55.y This valve conslsts of a. slidable plug 59 normally pressed against a seat 65 by an adjustable spring 6I. When the, plug 55v is positioned on the seat 65 its lower face is opened to the air pressure in the passage 51 and one of its side surfaces closes the port 52 leading to the air passage 38 in the cylinder head. Thus the valve 55 normally closes communication between the outlet passage 51 of the intercooler 45 and the passage 36 in the cylinder head and opens communication between these passages when the pressure in the passage 51 exceeds the tension of the spring 5 i.

A fuel injector pump 65 is arranged to be driven so as to inJect fuel into the combustion chamber 35 once during each reciprocation of the piston. Conveniently the pump may be' connected directly to the cam shaft 26 as illustrated in Fig. 2. Any suitable type of pump may be used. The illustrated embodiment consists of a casing 55 containing a crankshaft 51 driving a connecting rod 65 pivoted to a piston 65,v The piston reciprocates within a rotatably adjustable sleeve 15 which can be turned to different. angular positions by the arm 1I. An annular passage 12 is fuel.

formed to surround the portion of the casing 55 containing the sleeve 15, and is arranged to communicate with the interior of the sleeve through an opening 13 cut through the wall of the casing 55. The sleeve 15 is formed with a relatively narrow opening 14 arranged to register with the opening I3 in different angular positions of the sleeve 15. The annular chamber 12 is connected through a pipe 15 to a fuel pump 16 which draws fuel from a main tank 11, and is also provided with a return pipe `15 leading back to the fuel tank 11. Thus when the pump 16 is operated the annular chamber 12 is maintained full of The piston 59 has an inclined upper face 15 which cooperates with the slot -14 in the sleeve 15 to vary the quantity of fuel pumped on each stroke depending on the annular position of the sleeve 15. The interior of the casing 55 above the piston 56 communicates through a check valve 55 with the pipe,.5l which leads to anin- .lector nozzle 52 opening into the interior of the combustion chamber 35.

Assuming the space above the piston 55 has first been filled with liquid fuel, the piston on its down stroke draws in additional fuel from the annular chamber 12 through the opening 13 and the slot 14. On its up stroke fuel is returned from the interior of the sleeve 15 to the annular chamber 12 until the inclined upper face 15 of I the piston 69 passes the upper edge of the slot 14. Through the remainder of the upward stroke of the piston fuel is .forced through the check valve.65 and the pipe 5I into the combustion chamber 3,5, 'With the sleeve 15 turned so as tov position the slot 14 as illustrated in Fig. 3, the piston 56 moves but a short distance after passing the upper end of the slot 14 so that a rela-v tively small amount of fuel is pumped on each stroke. By turning the sleeve 15 so as to position the slot 14 adjacent the-opposite side of the opening 13 a greater portion of the stroke of the piston occurs after the upper edge of the pistonv has passed the upper edge of the slot 14 so that a larger quantity of fuel is pumped on each stroke.

The air vintake

passages

42 and 48 are provided with

throttle valves

85 and 85 respectively. The

- air outlet passage 55 is also preferably provided with a valve 51 which in one position opens the passage 55 to the atmosphere through a port 55 and in another position closes the passage 55 from the atmosphere so that air forced thereinto must pass-through the check valve 56 into the intercooler 46. The throttle valve 65 and the arm 1I which adjusts the position of the sleeve 15 in the fuel pump 65 may be manipullated simultaneously engine is preferably proportioned so that the ratio between the displacement volume of the cylinder 8 on the under side of the piston I9 and the volume of the combustion chamber 35 is equal to the desired maximum compression ratio of the engine. The displacement volume of the space within the skirt I4 and above the cross-head 22 may then be used as a supercharger to compensate for the reduction ofatmospheric pressur caused by increases in altitude.

To start the engine arranged in this manner the throttle 85 and the control arm 1I ofthe fuel injector pump may be left in closed position, the valve 91 closed, the valve 96 opened and the engine turned over by any suitable starting motor until the desired maximum pressure isbuilt up in the intercooler 46. The valve 81 may then be opened so that the cross-head 22 pumps idly without load and the throttle 85 and injector pump control 1I opened to admit air and fuel. Each upward stroke ofthe piston I9 inspires avquantity of air through the port 4I and thel air intake 42, the quantity depending upon the degree of opening of the throttle valve 85. Each downward stroke of the piston forces the inspired air into the intercooler 46. By reason of the cooling of the air in the intercooler a substantial part of the heat of compression is removed so that the pressure in the intercooler increases substantialvly in `accordance with the law of isothermal compression. The tension of the spring 6I is set at some value in excess of atmospheric pressure and less than the maximum pressure that would be obtained by isothermal compression of a volume f air equal to the displacement volume on the under side of the piston I9 into the volume of the combustion chamber 35. This can be a relatively high compresssion ratio since the compression is not limited by the rise in temperature of the air which occurs in the adiabatic compression in the ordinary engine. Preferably the compression ratio is on the order of 17 to l, a ratio such that if the compression were adiabatic thetemperature of the air would exceed the ignition temperature of the fuel.

Preferably the tension of the spring 5I is ad- -justed to be but slightly less than the maximum compression pressure. After the intercooler 46 has been filled withV air at a pressure which just balances the tension of the spring 6I, the additional quantity of air forced into the intercooler by any given stroke of the piston I9 raises the valve 58 against the tension of thespring 8| and holds the valve raised so that the outlet 51 of the intercooler is open through the port 62 to the passage 98 in the cylinder head until a quantity of air equal to that forced into the intercooler hasvpassed out through the port 62.` During the next upward stroke of the piston I9 the sleeve valve I9 closes the port 36, so that the combustion chamber 35 is separated from the -cylinder 9,

and thereafter opens the port 31 so that air can enter the combustion chamber 35 from the intercooler 46. Y As soon as a quantity of air equal in weightv to that forced into the intercooler on the A preceding stroke of the piston I9 has entered the combustion chamber 35 the valve 58 is again closed by the spring 6I. Thereafter as the piston I 9 continues its upward stroke the sleeve valve I9 closes the port 31 and fuel is injected lnto the combustion chamberl through the .injector 82. At aboutthe time the piston I'9 reaches its upper dead center the valve 96Lis opened anc'. the combustible mixture in the chamber 95 is: fired by any suitable means, such as the spark plug 90. The exact relation between the firing ofthe mixture; the opening of the valve 98 and the pnsition of the piston I9 may be varied slightly to obtain the best results. Preferably the firing is linitiated before the piston I9 reaches its top center ar. d the valve is opened before ignition is complete, so as to avoid building up too great a pressure in the combustion chamber 95.

After the mixture in the chamber 95 has been ignitedand the valve 96 has opened so as to establish communication between the combustion chamber and the interior of the cylinder 9, expansion of the gases forces the piston I9 downwardly on its next stroke. Ata suitable point during the downward movement of the piston I9, as for example'at between 40 and 60 prior to bottom dead center, the cam 94 opens the exhaust valve 92 so that thecylinder may blow down to or below atmospheric pressure before the piston I9 reaches its bottom dead center. After the ypressure in the cylinderv 9 and the combustion chamber 95 have been reduced substantially to atmospheric pressure, and at a point near the vbottom dead center of the piston I9, the sleeve valve I9 closes the port 96 so that the combustion chamber 95 is again separated from the cylinder 8. During the upward stroke of the Ipiston I9 the exhaust valve 92 remains open -so that the exhaust gases in the cylinder 8 are swept the quantity of air inspired on the under side of the piston I9 and forced into the intercooler 46` on the preceding stroke. This in turn depends upon the setting of the throttlelvalve 95. I'hus the `control 'II for the fuel injector pump may be adjusted simultaneously with the movement of the throttle valve 85. The pump will inject the correct :quantity of fuel into the combustion chamber for the quantity'of air admitted from the intercooler 46. The response of the engine to changes of the throttle valve 95 and the injector pump control 1I is thus substantially instantaneous, regardless of the volume of air compressed in the intercooler 46.

The engine may then be supercharged to compensate for reductions in atmospheric pressure caused by an increase in altitude by closing the valve 81 and opening the valve 86 in proportion to the reduction in atmospheric pressure.

The engine controls may also be arranged so that the compression space above the cross-head 22 serves as an overcharger operating throughout the normal range of operation of the engine at sea level. For this purpose the combustion chamber 95 is increased in size so that the ratio of its volumeto the combined volumes of the cylinder 8 lon the under side of the piston I9 and the displacement volume above the cross-head 22 is equal to the desired compression ratio. The valve 81 is then maintained closed and the

throttle valves

85 and 86 and the .control 1I for the fuel injector pump Iare manipulated. The fuel injector pump is arranged to supply a greater quantity of fuel at any particular setting to conform to the greater quantity of air compressed y the correct amount for the particular length of stroke and diameter of skirt id included in the engine. v

, Although a preferred embodiment of the invention has been described it will be understood that the invention is not limited thereto. The pressure regulating valve, for example, may be used -either in the engine disclosed, or in an engine such as that shown in my Patent No. 2,220,- 926, in which a combustible mixture of fuel and air is compressed into the intercooler. Similarly, other variations and rearrangements of the parts may be resorted to without departing from the scope of the invention as defined in the following claims. n

I claim:

1. In combination with an external combustion engine having a combustion chamber, a reservoir of compressed gas, means driven by the engine for compressing gas into said reservoir, a throttle valve controlling the pressure of the gas compressed by said means, a conduit for admitting gas from said reservoir into said combustion chamber, a valve operated by said engine interposed in said conduit, a pump for injecting controllable quantities of fuel into said combustion chamber, a regulating valve in said conduit interposed between said reservoir and said first named valve, and means exertinga constant pressure on said regulating valve urging the same toward closed position to interrupt communication between said reservoir and said engine, said regulating valve being urged toward open position by the pressure in said reservoir.

2. In combination with an external combustion engine having a combustion chamber, a reservoir ofV compressed gas, means driven by the engine for inspiring and compressing gas into said reservoir, a throttle valve controlling the pressure of the gas inspired by said means, a, valve operated by said engine for admitting gas from said reservoir into said combustion chamber once during each cycle of the engine, a pump for injecting fuel into said combustion chamber once during each cycle of the engine, a regulating valve interposed between said reservoir and said engine, and means exerting a constant pressure on said regulating valve urging the same toward closed position to interrupt communication between said reservoir and said engine, said -regulating valve being urged toward open position by the pressure in said reservoir. 4

3. An external combustin engine comprising a main cylinder, a double-acting piston reciprocable in said cylinder, an auxiliary cylinder aligned with said main cylinder, means closing the adjacent ends of said main and auxiliary cylinders, a cross-head reciproeable in said auxiliary cylinder, a piston rod connecting said piston with said cross-head and extending through said closure means, a combustion chamber having a I removable plug adapted to be varied in length to vary the volume of said chamber, an intercooler, valve means arranged to open one end of said main cylinder alternately to a gas intake and to said intercooler, valve means to open said auxiliary cylinder alternately to said intercooler and to a gas intake, a check valve interposed between said intercooler and said auxiliary cylinder, a second check-valve interposed between said intercooler and said end of said main cylinder, valve means to open said combustion chamber alternately tov said intercooler and to the other end of said main cylinder, and valve means to open saidauxiliary cylinder to atmosphere to render the same inoperative when desired.

4. An external combustion engine comprising a main cylinder having power and compression ends, a double-action piston reciprocable in said cylinder, an auxilairy cylinder aligned with said main cylinder, meansclosing the adjacent ends of said main and auxiliary cylinders, a crosshead piston reciprocable in said auxiliary cylinder, a piston rod connecting said double-actingv piston and said cross-head piston and extending through said closure means, an intercooler, valve means arranged to open the compression end of said main cylinder alternately to an air intake and to said intercooler, valve means to open said auxiliary cylinder alternately to said intercooler and to an air intake, check valve means between said auxiliary cylinder and said intercooler, check valve means between the compression end of said main cylinder and said intercooler, a combustion chamber, valve means to open said combustion chamber alternately to said intercooler and to the power end of said main cylinder, pressure regulating valve means between said combustion chamber and said intercooler, a pump for injecting fuel into said combustion chamber once during each cycle of said engine while said combustion chamber is closed from said intercooler and from the power end of said main cylinder, and ignition means in said combustion chamber arranged to initiate tiring of the mixture in said 'combustion chamber, while said combustion chamber is closed from said intercooler and from the power end of said main cylinder.

5. An external combustion engine comprising 'a main cylinder having -power and compression ends, a double-acting piston reciprocable in said cylinder, an auxiliary cylinder aligned with said main cylinder, means closing the adjacent ends of said main and auxiliary cylinders, a crosshead reciprocable in said auxiliary cylinder, a piston rod connecting said piston with said crosshead and extending through said closure means, a combustion chamber, an intercooler, and a sleeve valve slidably mounted within said main cylinder and surrounding said auxiliary cylinder, said sleeve valve having ports arranged to open the compression end of said main cylinder alter-- nately to an air intake and to said intercooler, a feather valve interposed between said intercooler and the compression end of said main cylinder, ports to open said auxiliary cylinder alternately to said intercooler and to an air intake, a second feather valve interposed between said intercooler and said auxiliary cylinder, ports to open said combustion chamber alternately to said intercooler and to the power end of said main cylinder, a pressure regulating valve interposed between said intercooler and said combustion chamber, and a Dump for injecting fuel into said combustion chamber after said combustion chamber has been closed from said intercooler and before said combustion chamber is opened to the l main cylinder, means closing the adjacent ends of said main and auxiliary cylinders, a cross-head reciprocable in said auxiliary cylinder, a piston rod connecting said piston withsaid cross-head and extending through said closure means, a combustion chamber, an intercooler, a pressure regulating valve interposed between said intercooler and said combustion chamber, and a sleeve valve slidably mounted within said main cylinder and surrounding said auxiliary cylinder, said sleeve valve having ports arranged to open the compression end of said main cylinder alternately to an air intake and to said intercooler, ports to open said auxiliary cylinder alternately to said intercooler and to an air intake, ports to open said combustion chamber alternately to said intercooler and to the power end of said main cylinder, a pump for injecting fuel into said combustion chamber after said combustion chamber has been closed from said intercooler and before said combustion chamber is opened to the power end of said main cylinder, and ignition means arranged to initiate ring of the mixture in said combustion chamber prior to the opening of said combustion chamber to the power end of said main cylinder.

7. In an external combustion' engine of the fuel injection type, a combustion chamber, a reservoir for compressed air, means driven by the engine for compressing air into said reservoir, a pump driven by said engine for injecting fuel into said combustion chamber, means for controlling the quantity of fuel injected into said combustion chamber, a conduit for admitting air from said reservoir into said combustion chamber, a valve operated by said engine in said conduit, a second valve interposed between the first named valve and said reservoir., means exerting` a constant pressure on said second valve urging the same toward closed position to interrupt communication between said reservoir and said combustion chamber, said second valve being urged toward open position by the pressure in said reservoir and means for controlling the quantity of air compressed into said reservoir independently of the control of said pump, whereby air pressure suiilcient to open said second valve may be built up in said reservoir before fuel is admitted to said combustion chamber to start the engine.

8. An external combustion engine comprising a main cylinder having power `and compression ends, a double-acting piston reciprocable in said cylinder, an auxiliary cylinder aligned with said main cylinder, means closing the adjacent ends of said main and said auxiliary cylinders, a crosshead reciprocable in said auxiliary cylinder, a piston rod connecting said piston with said crosshead and extending through said closure means, an intercooler, valve means arranged to open the compression end of said main cylinder alternately to an air intake and to said intercooler, valve means to open said auxiliary cylinder alternately to said intercooler and to an air intake, a comf bustion chamber, means for injecting fuel into said combustion chamber, valve means to open tercooler and to the power end of said main cylinder, a regulating valve interposed between said intercooler and said combustion chamber, and means exerting a constant pressure von said regulating valve urging the same toward closed position, said regulating valve being'urged toward open position by the pressure in said Intercooler.

DANIEL MICHEL WEIGEL.

REFERENCES CITED The following references are of record inthe file of this patent:

UNITED STATES PATENTS Number Name Date 753,086 Mains Feb. 23, 1904 1,237,373 Nordberg Aug. 21, 1917 1,301,036 Cage Apr. 15, 1919 1,386,394 Cager Aug. 2, 1921 1,393,831 l Rossman Oct. 18, 1921 1,518,983 Hyvernaud Dec. 9, 1924 1,878,326 Ricardo Sept. 20, 1932 1,955,620 Bchi Apr. 217, 1934 2,131,216 Brooke Sept. :27, 1938 2,220,926 Weigel Nov. 12, 1940 2,227,896 Fitzgerald Jan. 7, 1941 FOREIGN PATENTS Number Country Date 611,212 France June 28, 1926 219,469 Germany Feb. 28, 1910 247,745 Germany June 6, 1912