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Aug- 21, l956 o. GRlGAR COMBINATION 2,759,771 AND FUEL INJECTION NOzzLEs Filed April 5o, 1954

ah. 1 2,759,771 United States Patent O ICC Patented Aug. 21, 1956

2 two- or four-stroke internal combustion engine, or with the combustion chambers of combustion turbines. The apparatus includes a body 1 and a plunger 2 hav 2,759,771 ing parts of different cross sections. 'I‘he part 2a of the COD/[BINATION FUEL INJECTION PUMP AND plunger, which has a larger diameter than the part 2b, FUEL INJECTION NOZZLES forms the plunger proper. Fuel enters at 17 (see Fig. l) and passes through 13a (Fig. 4) into the barrel of the Otto Grîgar, Zurich, Switzerland body 1. The fuel supply is controlled by a valve 4 which Application April 30, 1954, Serial No. 426,886 is sealed by means of a gasket 7 and a packing 6, and may be rotated by means of a lever 5. It is secured by Claims priority, application Switzerland May 2, 1953 a spring washer 8. The lever 5 serves to meter the fuel 5 Claims. (Cl. 299-1072) supply. The free end or lower portion 2g of the plunger 2 is provided with fine longitudinally extending grooves 2c which are partially exposed when the plunger is in its 15 lowest position (see Fig. 4). Instead of longitudinally This invention relates to a combination fuel injection extending grooves, helically winding grooves may be pro pump and fuel injection nozzles. vided as well. The grooves 2c act as nozzles and coop Fuel injection for internal combustion engines erate with a 3 and a coil spring 9. The piston 3 reciprocates in a fuel storage chamber. Fuel under pres and especially diesel engines have been known. So far, 20 such fuel pumps have proved to be economical only for sure is forced through the nozzles which deliver a fog of combustion engines of relatively high output. It is dif fuel in the form of a into a . ñcult to manufacture nozzles with sufficiently fine open The operation of the diíerential plunger 2 can readily ings, and, in addition, the known nozzle constructions be predetermined as to timing and the relation of crank shaft position and moment of injection. tend to break down. Also, the timing of the injection 25 is influenced by the prevailing fuel pressure so that rapid The diiîerential plunger may be operated, for instance, periodic changes in fuel pressure may cause repeated re directly from a or over a and push injections into the combustion chamber. This causes rod. The plunger is returned by a helical spring 10, and uneven running of the engine, which at increasing speed the stroke of the plunger is limited by a cap nut 11 which, of the motor involves the additional disadvantage of an 30 in turn, is secured in its position by a lock nut 12. The undesired increase in fuel supply. fuel conduit 13a is sealed by plugs 13 and 14. The primary object of my invention is to generally im The piston 3 is operated by the fuel pressure over the prove fuel injection pumps and fuel injection nozzles. connecting duct 15a as well as by the action of the helical The invention aims at a combination pump and nozzles, spring 9. The space in which the piston moves, which combination will not have the disadvantages of 35 and the helical spring is accommodated, is closed at its many prior art pumps and prior art nozzles but instead ends by a plug l5 and 15b, respectively. will embody commercially desired important advantages, The fuel injection pump and the injection nozzles are such as sirnpleness and sturdiness in construction, high continuously lubricated, oil being admitted through a efficiency, economy, and wide applicability. connection piece l@ (Fig. l) to the annular space 19a, and One object of my invention is to provide a combina 40 thence through the duct f9.5 to another annular .space 19e, tion fuel injection pump and nozzles. from where the oil passes through duct 19d (Fig. 3) and Another object of the present invention is to provide through the connection piece 19e back to the oil tank a combination pump and nozzles of the referred to kind, (not shown). which will deliver both large and very small amounts of The plunger 2 is provided with transversely extending fuel at any rotary speed equally well. 45 holes 2d which, with the differential plunger in its top A further object of this invention is to provide a com position, are on the level of the annular space 19C. The bination fuel injection pump and nozzles, which is suitable oil required for lubrication passes from the holes 2d for two-stroke and four-stroke cycle engines, for combus through a longitudinal in the plunger to the nozzle tion turbines, as an ignition injector for semi-diesel body 2g. There, the oil emerges through one of the (Otto-Diesel) engines, as a fuel atomizer for furnaces 50 transverse bores 2e and thus lubricates the nozzle body. using liquid fuels, as a countercurrent condenser, for The oil that collects from the pressure regulator 3 and instance, for steam turbines, etc. the differential plunger is returned through the duct 20 To the accomplishment of the foregoing and other to the drain 18. objects which will appear hereinafter, my invention con The combination fuel injection pump and injection noz sists in the apparatus elements and their relation one to 55 zles operates as follows: the other, as are more particularly described in the speci The differential plunger moves into its highest posi ñcation and sought to be defined in the claims. tion, thereby creating a vacuum in the annular space 2f The specification is accompanied by a drawing in into which space fuel is sucked, filling at the same time which: the connecting duct 15a. During the downward or work Fig. 1 is a plan view of a combination fuel injection 60 ing strokes of the plunger 2 the pressure in the pump pump and fuel injection nozzles, embodying features of cylinder increases and causes fuel to flow through the my invention; duct 15a and to act upon the front surface `of the piston Fig. 2 is a longitudinal section taken in the plane of 3. The latter is caused to move upward under the inilu the line D-D of Fig. l; ence of the fuel pressure and against the action of the Fig. 3 is a longitudinal section taken in the plane of 65 spring 9. Towards the end `of the working strokes, as the line F-F of Fig. l; and the pressure in the pump cylinder decreases, piston 3, Fig. 4 is a fragmentary longitudinal section correspond under the pressure of the spring 9, forces fuel stored in ing to that shown in Fig. 2 but illustrating a different the storage chamber back into the pump cylinder. When working position. the iìne grooves 2c of the nozzle 2g become exposed Referring to the drawing, the combination pump and 70 beyond the threaded lower end lb of the body 1, fuel nozzles, selected for illustration, is constructed to be is sprayed into the combustion space as a fog. The individually associated with each working cylinder of a amount of fuel required is regulated by the rotary valve 4. 2,759,771 3 4 Heat generated at the and at the fuel l. Combination fuel injection pump and fuel injection injection pump is of beneficial effect because a vapor nozzles, comprising a body, a pump cylinder provided cushion formed by the evaporation of the fuel is with. in the body, a plunger to reciprocate within the cylinder, =out unfavorable inñuence on the operation of the engine. fuel conveying means leading to the cylinder, valve means This is due tothe fact that the injection nozzles are controlling the fuel supply, at least a single fuel storage opened and closed by positively guided motions. If com chamber likewise provided in the body, fuel conduit bustion engines operate with separate means for ignition, means connecting the cylinder and the storage chamber, the fuel is injected when valves and ducts are closed. a piston reciprocating within said chamber, compression With a two or four-stroke combustion engine, the appa spring means housed Within the chamber and acting upon ratus of the invention may be adapted for all kinds of 10 the piston to force stored fuel back into the cylinder, fuel. Fuel, such as gasoline, which is injected directly grooves provided on the lower end portion of the plunger into the combustion chamber need not be given special and serving as nozzles, the groovelike nozzles being free anti-knock properties. to deliver a fuel spray into a combustion space when It is believed that the construction and operation of the plunger moves into its lowest position. the apparatus of the present invention, as well as the 15 2. In the apparatus according to claim 1, the plunger many advantages thereof, will be understood from the including two portions of different diameters, there being foregoing detailed description. Some of these advan an annular space between the smaller diameter portion tages are reviewed hereinafter. of the plunger and the pump cylinder, said fuel convey The apparatus is simple and sturdy and operates with ing means opening into said annular space when the out valves. It is suited to deliver large as Well as small 20 plunger is in its highest position. amounts of fuels (as small as 0.7 mm.3 per stroke). 3. In the apparatus according to claim l, the spring The possibility of handling very small amounts of fuel means bearing against the piston at the latter’s upper makes it possible to use the apparatus of the invention end, the fuel conduit means being provided at the down as an ignition injector for easily ñammable fuels. This ward end of the cylinder and permitting the discharge of permits the development of combustion engines of all 25 the stored fuel during the downward stroke of the plunger kinds, even of those with a cylinder volume of less than until the nozzles are free to deliver the fuel spray. 200 cubic centimeters, for use of fuels of relatively high 4. In the apparatus according to claim 1, said grooves heat of ignition at moderate compression ratios (ring extending longitudinally. system). The injected ignition fuel forms an ignition 5. The apparatus according to claim 1, forming a unit ñame several hundred times larger than the spark from 30 to be individually associated with each working cylinder an electric , and furnishes additional heat, or combustion chamber of an internal combustion engine which not only eliminates the disadvantages of delayed and a combustion turbine, respectively, comprising means ignition, but also permit-s higher rotary speed. Such com­ to secure the apparatus to the engine or turbine and to bustion engines operate at a very high efficiency. operatively connect the apparatus to the respective com The provision of grooves to serve as nozzles has the 35 bustion space. advantage that the fuel is injected into the combustion space in streams, the direction of which changes during References Cited in the file of this patent the injection. UNITED STATES PATENTS The predetermined rhythm of the injections ensures 2,037,702 Butler ______Apr. 2l, 1936 smooth running of the engine at any speed. 40 2,055,578 Hurst ______Sept. 29, 1936 It will be apparent that while I have shown and de 2,088,007 Zumbusch ______July 27, 1937 scribed my invention in a single form only, many changes 2,295,081 Harvath ______Sept. 8, 1942 and modifications may be made without departing from the spirit of the invention defined in the following claims. I claim: 45