US2035265A

US2035265A - Fuel injection device

Info

Publication number: US2035265A
Application number: US695552A
Authority: US
Inventors: Herbert C Edwards
Original assignee: Packard Motor Car Co
Current assignee: Packard Motor Car Co
Priority date: 1932-09-17
Filing date: 1933-10-28
Publication date: 1936-03-24
Anticipated expiration: 1953-03-24

Description

March 24, 1936. H C. EDWARDS 2,035,265

FUEL INJECTION DEVIC E original Filed sept. 17, i952 HERBERT ./.I EDNHRDE.

Patented Mar. 24, 1936 UNITED STATES PATENT. OFFICE 2,035,265 n FUEL INJECTION DEVICE Original application September 17, 1932, Serial No. 633,651. Divided and this application ctober 28, 1933, Serial No. 695,552k

12 Claims. (Cl. 299-107.@ f

This invention relates to internal combustion engines and more particularly to fuel injection devices, this application being a division of my pending application Serial No. 633,651, flled September 17, 1932.

An object of the invention is to provide a new and novel device for spraying two jets of liquid fuel into a combustion chamber of an internal combustion engine.

Another object of the' invention is to provide a fuel injection device having a valve which will open under pressure and form with the nozzle casing two angularly disposed openings from which jets of different volume will be projected.

A further object of my invention is to provide an injection nozzle through which two sprays of I liquid fuel are projected from a single opening in dierent volume.

Other objects of the invention will appear from the following description taken in connection with the drawing, which forms a part of this specication, and in which:

Fig. 1 is a fragmentary sectional view of a cylinder and a fuel injection device incorporating my invention;

Fig. 2 is an enlarged sectional view taken on line 2-2 of Fig. 3 of the outlet end portion of the injection device which is several times the actual size;

Fig. 3 is an elevational view of the outlet end of the injection device shown in Fig. 2;

Fig. 4 is a sectional View through the engine cylinder showing the relation of the injection device with the combustion chamber, the valves being shown diagrammatically;

Fig. 5'is a fragmentary sectional view ofthe nozzle taken on line 5-5 of Fig. 3;

Referring now to the drawing by characters of reference, I0 indicates an internal combustion engine cylinder in which a piston I IA is arranged to reciprocate. The cylinder head I2 is formed with a pair of ports (not shown), one of which provides for the intake of air and the other for expulsion of exhaust gases. An inlet valve I4 closes the inlet port and another valve I5 closes the outlet port, such valves opening inwardly of the cylinder through means of suitable engine operated mechanism (not shown).

In order to reduce the charge containing space to provide the high compression ratio desirable for compression-ignition engines and to allow for valve clearance, I provide the piston face I6 with a depression or pocket I'I which, with the cylinder head, forms the combustion chamber. Such depression must necessarily encompass the space into which the valves extend when open and one wall I8 thereof curves slightly so as to interfere as little as possible with the rotational movement of air therein. Liquid fuel charges are sprayed into the cylinder by injection means havingz an improved form of nozzle construction which will project two angularly disposed streams of different volume from a single opening, the larger stream being directed into the air charges against the current at one end of the pocket and the smaller stream being directed into the air charges with the current at the other end of the pocket.

A nozzle'casing I9 is formed with a neck 20 which screws into a pump casing 2l and engages the bushing 22 in a manner clamping barrel 23 in the pump casing. The barrel and pump casing are formed withI radial ports 24 which are controlled by the reciprocation of the plunger 25. The nozzle casing has an extension 26 screwed thereon which projects through an aperture in the cylinder wall adjacent the cylinder head. and this entire injection device can be fixed rigidly to the cylinder by suitable fastening means. The passage 21 extends axially through the nozzle casing extension and partially through the'nozzle casing and communicates with the interior oi the barrel, suitable one-way check va1ves'28 being provided to prevent the return of fuel oil from the nozzle to the pump. The valve member 29 extends through the extension passage and into the nozzle casing passage. On the interior end thereof is screwed a bearing member 30 having an axially slotted peripheral wall which slidably engages with the nozzle casing. Stop member 3| is arranged in the casing to limit movement of the valve bearing in a direction away from the cylinder and is preferably adjusted so that the valve head 32 can never quite seat. Coil spring 33 is arranged in the nozzle casing passage and normally urges the valve member toward closed position and also limits movement thereof in the opposite or opening direction. I'he nozzle and pump structure so far described forms the subject matter of Patent No. 1;934,296 to Hermann I. A. Dorner, and reference can be had thereto for a more complete understanding of the device if desired.

A conical spray is projected from a nozzle shown in the patent just mentioned due to the valve head and its seat in the outlet passage being conical. For some forms of combustion chambers, this type of spray is satisfactory to efficiently intermingle the atomized liquid fuel with the air charges, but with a combustion chamber of the character herein described, a conical spray is inefficient as fuel would be carried into the end of the chamber adjacent the exhaust valve and collect therein without properly intermingling with the air and, as a result, there would be a quantity of unused air and carbonizing of the fuel oil in the end of the chamber adjacent the exhaust valve would take place.

In order to properly introduce the atomized liquid fuel into air charges in a cylinder having an elongated chamber of the character described, I have provided an improved form of nozzle discharge end whereby two streams of fuel will be projected in a particular manner more fully described hereinafter. The interior wall surface of the outlet end of the nozzle extension is formed with two diametrically disposed

conical portions

35 and 36 and with two other diametrically disposed

curved surfaces

31 and 38. The

surfaces

35 and 36 are formed so that they are segments of a similar cone whereas the

curved surfaces

31 and 38 are formed with different radii and so that the distance between the curved surfaces is different adjacent the two conical surfaces. These curved surfaces extend axially of the casing extension as segments of cylinders and provide a bearing for the head of the valve and the

conical surfaces

35 and 36 provide the passage wall portions past which liquid fuel is projected from the injection device.

The head portion o f the valve member is formed with two surfaces 33 which are formed complementary to the

surfaces

31 and 38 of the extension casing respectively so that they will have a close sliding fit therewith axially of the nozzle. Joining these two curved surfaces -of the valve head are segmental conical surfaces 40, the angle of which is different from the angle of the adjacent conical surfaces of the'nozzle extension casing. The valve is reduced in diameter at the inner end of the conical surfaces 40 so that knife edge portions, as indicated at 4|, are formed at the inner termination of said surfaces. Such knife edge portions cooperate with the conical surfaces of the nozzle extension casing to form two arcuate spaces through which fuel passes from the nozzle, the curved surfaces 39 of the valve fitting closely against the

curved surfaces

31 and 38 of the casing to prevent escape of oil therebetween. The valve stem portion 41 which extends into the passage in the nozzle extension has a small amount of clearance to permit a small lateral movement thereof and it is grooved axially to allow fuel to flow freely through the extension. As the valve stem is carried by the bearing member 30 slidably engaging the nozzle casing and is movable laterally due to clearance, there is a flexing movement thereof when the head is shifted normal to its axis.

With the form of nozzle outlet just described, it will be observed that the outlet space between the valve head and the surface 36 is of less length circularly than the space between the valve head and the surface 35 so that a more compact spray will issue from the shorter space than will issue from the longer space'. When pressure is applied to the fluid in the nozzle, the valve member is moved axially toward the interior of the cylinder and laterally toward the surface 35 as indicated by dotted lines in Fig. 2.- This lateral movement takes place because of the impossibility of movement in the other direction due to the decreasing width between the

walls

31 and 38 when the fuel pressure builds up against the head. As a result of this lateral movement of the valve, a greater volume of fue! oil will pass from the nozzle extension casing by the surface 36 than will pass by the surface 35. The nozzle is associated with the cylinder so that the surface 35 points toward the end of the piston pocket adjacentthe exhaust valve while the surface 36 points toward the end of the piston pocket aci-- jacent the air intake valve and, as a result, a greater volume of oil will be projected into the rotating air charge in the pocketin a direction Aopposing theair current.

The piston head is formed with a depression 43 so that it can telescope the outlet end of the nozzle and its valve, and it is also formed with a pocket portion 44 having angularly disposed walls formed to permit the introduction of the two fuel sprays into the far ends of the piston pocket without interference when the piston is substantially at top center position. This pocket portion 44 forms a continuation and part of the pocket i1.

The engine illustrated is of the four-stroke cycle type and air charges entering the cylinder will rotate during the compression strokes of the piston. As the piston approaches top center, theinjection mechanism is actuated to project charges of fuel into the compressed rotating air and ignition occurs, through the heat developed, while the compression stroke is completed. With the nozzle herein described, two angularly disposed sprays are introduced into the compressed the main portion of the fuel charge will be well.

intermingled with the rotating air charge during its travel from the inlet valve end of the pocket to the exhaust valve end of the pocket. 'I'he smaller spray is of such a volume that there will be no excess fuel directed into the air at the exhaust end of the pocket and that which is injected will thoroughly mix with the rotating air.

By this arrangement of sprays, the liquid fuel will become thoroughly intermingled with the air charges and will not be carried by the air current to the end of pocket adjacent the exhaust valve in a volume or condition such that the liquid fuel will collect therein, and thus the intermingling of the fuel charges will be of such a nature that efficient operation of the engine will result.

Although the invention has been described in connection with a specic embodiment, the principles involved are susceptible of numerous other applications which will readily occur to persons skilled in the art. The invention is therefore to be limited only as indicated by the scope of the appended claims.

What I claim is:

1. In a fuel injection device, a nozzle comprising a casing formed with an outlet passage, and a flexible valve axially reciprocable in the casing passage, said valve and casing having a pair of diverging complementary engaging bearing- 2. In a fuel injection device, a nozzle comprising a casing formed with an outlet passage, and a valve axially reciprocable in the casing passage,

aosaaea l 4 y3 said valve and casing each having a pair of diverging complementary engaging bearing surfaces and conical surfaces intermediate the bearing surfaces adapted4 to form arcuate openings therebetween, said valve being movable in a direction to vary the size of the outlet openings while unseated.

3. In a fuel injection device, a nozzle comprising a casing formed with an outlet passage, and a flexible valve axially reciprocable in the passage, said valve and casing having co-operating diverging bearing surfaces and having other surfaces associated to form openings therebetween, said valve being movable normal to its axis tovary the size of the openings relatively While unseated.

4. In a fuel injection device, a nozzle comprising a casing formed with an outlet passage, and a valve axially reciprocable in the passage, said valve and casing each having engaging arcuate bearing faces and faces intermediate the bearingfaces cooperating to form outlet openings therebetween, the pairs of bearing faces having different radii and centers, said valve being movable normal to its axis and in a direction to vary the size of outward openings relatively while unseated.

5. In a fuel injection device, a nozzle comprising a. casing formed with an outlet passage, and a valve axially reciprocable in the passage, said valve and casing each having a pair of similar engaging bearing surfaces gradually diverging from one end to the other end, and having another pair of complementary surfaces co-operating to form two outlet openings from the passage, said valve being movable normal to its axis to vary the size of the outlet openings relatively while unseated.

6. In a fuel injection device, a nozzle comprising a casing having a fuel passage therein, and an axially reciprocable valve member in the passage having a flexible shaft with a head at one end and a bearing at the other end, said head and said casing having complementary diverging bearing surfaces and other complementary surfaces forming a pair of outlet openings, said headV being laterally movable by the force of uid pressure in the casing passage to vary the size of the openings relatively.

7. In a fuel injection device, a nozzle comprising a casing having a passage therein, said passage forming at one end of the casing a pair of bearing surfaces and outlet surfaces intermediate the bearing surfaces, a valve head in the outlet end of the passage having bearing surfaces complementary to and engaging the casing bearing surfaces, the portions of said head intermediate the bearing surfaces cooperating with the adjacent casing surfaces to form outlet openings, a exible stem in the passage fixed to the valve head, said head being movable normal to its axis between the bearing surfaces of the casing under pressure of fluid to vary the size of the outlet openings, and spring means exerting pressure in a direction to normally seat the head outlet surfaces against the casing outlet surfaces.

8. In a fuel injection device, a nozzle comprising a casing having an outlet passage therein, said passage forming at one end of the casing a pair of bearing surfaces and intermediate conical outlet surfaces. a valve head in the outlet end of the passage having bearing surfaces complementary to and engaging the bearing surfaces of the casing, the portions of said head intermediate the bearing surfaces being conical and extending at a different angle than the conical surfaces of the casing and cooperating therewith to form outlet openings, a flexible stem in the passage fixed to the head, said head being movable normal to its axis under pressure of fluid in the casing to vary the relative size of the openings, and spring means exerting pressure in a direction to normally seat the conical portions of the lead against the conical portions of the casing.

9. In a fuel injection device, a nozzle comprising a casing having an outlet passage therein, said passage forming at one end ofthe casing a pair of bearing surfaces and intermediate outwardly flared conical outlet surfaces, a valve head in the outlet end of the passage having bearing surfaces complementary to and engaging the bearing surfaces of the casing, the portions of said head intermediate the bearing surfaces being conical and extending at a different angle than the conical surfaces of the casing and cooperating therewith to form outlet openings, a flexible stem in the passage fixed to the head, said head being movable normal to its axis under pressure of vfluid in the casing to vary the relative size of the openings, and spring means exerting pressure in a direction to normally seat the conical portions of the head against the conical portions of the casing.

l0. In a fuel injection device, a nozzle comprising a casing having an outlet passage therein, and a valve in the passage having a head and a flexible stem, said head being moved in a direction normal to its axis under pressure of uid passing through the nozzle to change its relation transversely of the opening. y

1l. In a fuel injection device, a nozzle having a passage therein, the outlet end of the passage being enlarged, a valve having a head portion in the enlarged end of the passage and a stem portion extending into the passage, the stem portion of the valve being flexible to allow movement of the valve head normal to its axis while unseated,

and means normally urging the valve head inwardly of the passage, said valve head being moved in a direction normal to its axis by fuel passing through the nozzle passage.

l2. In a fuel injection device, a nozzle casing formed with an outlet passage, and a valve axially reciprocable in the casing passage, said valve and said casing outlet each having a pair of curved complementary engaging bearing surfaces and surfaces intermediate the bearing surfaces adapt- 6( ed to form outlet openings therebetween, said valve being movable normal to its axis toward and away from one of the casing surfaces intermediate the bearing surfaces while unseated.

`HERBERT EDWARDS.