US2913986A - Devices for injecting fuel or other media into internal combustion engines - Google Patents

Description

W. B. SKIPPER NJ Nov 24, 1959 OR OTHER MEDIA TION ENGINES DEVICES FOR I ECTING FUEL INTO INTERNAL COMBUS Filed Nov. 1,

r 0 t n e U n I I i WILLIAM BURKE SK/HOER md F o 12 in the distributor.

United States Pater-1t Claims priority, application Great Britain `November 15, 1955 v This invention` relates to'devices forinjecting fuels (either of the lubricating kind or not) or other media such asanti-detonates `into internal combustion engines.

Devices forthis purposehave been proposed in which at least one delivery conduit and at least one pressure provision is made for charging the.-delivery conduit with a constantwquantity of fuel or. other` liquid (hereinafter referred ,to as fuel). at each return stroke of the partition and for usefully discharging the fuel on the forward strokes of the partition in proportions that can be manually varied.

An object of the present invention is to provide new and improved means for metering theffuel deliveries in a manually variable manner which enables the number of the moving parts of the device to be considerably reduced. l

ln accordance with the invention the device includes a distributor rotatable in the body of the device for controlling the periodic supply and discharge of pressure liquid to and from the or each pressure liquid chamber, a return llow passageway in the distributor for the presl sure liquid, and a manually operable valve'controlling the outlet from the passageway thereby to vary each return stroke of the movable partition which is preferably a movable piston and thus variably meters the quantity of fuel admitted on such stroke to the fuel delivery conduit.

By way of example one form of injection device in accordance with the invention is shown diagrammatically on the accompanying drawings.

Fig. l represents this form as a composite, longitudinal section on l-I of Fig. 2.

Fig. 2 represents a half end view and a half section in the plane ll-ll of Fig. l.

Fig. 3 represents a cross section in the plane III-Ill of Fig. l.

The same references are used throughout to denote the same or similar parts.

The body of the injection device comprises the two parts 1 and 2 detachably held together by stud bolts 3. Body part 2 isvprovided with a fuel inlet nipple 4 (shown only in Fig. l); with fuel outlet nipples 5, one for each engine cylinder, there being six in the present example which is intended for a sixcylnder, internal combustion engine; and with an inlet nipple 6 for a high pressure pumping liquid, and a return or outlet nipple 7 for this liquid.

Rotatably mounted in an axial bore 8 of the body part 2 there is a distributor 9 for the pumping liquid, this distributor having an annulus 10 in constant communication with the inlet nipple 6 via a duct 11 in the body part 2. An axial duct or passageway 41a in the distributor has an enlarged portion 42a at one end of the distributor. Annulus l communicates with a duct A manually operable control rod 14 projects through a small bore in one end of the body `liquidc'hamber are separated by a movable partition, and v `fluted stem.

2,913,986 Patented Nov. 24, ,1959

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. 2 Y part 2 into the bore 8, its inner end being formed as restriction 14a that co-acts with said larger portion 42a leading to .passageway 41a to control'the rate of return ow of liquid via a duct 42 and the return nipple 7. The other end of the distributor 9 has a shaft 16 rotatably mounted in the body part 1.

Extending through the body part 2 in line with each fuel outlet nipple is a bore 22. In each such bore 22 there is`a liner or barrel 23 affording a fuel delivery con duit 24 open to an annulus 25 via radial ducts or passage- Ways 26, andy housing a non-return valve 27' which is biased to its closed position by a spring 28 and which, when open, places the conduit 24 in communication with the pertaining fuel outlet nipple. Each valve 27 has a A freely oating piston or partition 37 within each liner or barrel 23 separates the fuel delivery duct 24 from a pressure liquid chamber 38 at the rear of the floating piston.` When the distributor 9 is'rotated, the pressure liquid chambers 38 are placed, in turn in communication with' the duct .f12.of the distributor by means of radial ducts 39(Figs; 1 and-3). These radial ducts 39 also `cotrnnunicate infturn with a radial duct or passageway 40a in the distributor leading via the axial duct 41a `and enlarged portions 42a and duct 42 back tothe outlet or return nipple 7.

The beforementioncd fuel inlet nipple 4 (Fig. 2) communicates with a fuel gallery 43 formed in the body part 2, this fuel gallery in turn communicating with the inlet chambers 44 (Fig. 1) of six fuel inlet valves each comprising a valve housing 45 screw-threaded into a corresponding bore in the housing part 2, and a tinted-stemmed valve member 46 biased to its seat in the valve housing by a spring 47. The bore containing this spring constitutes the outlet bore of the corresponding fuel inlet valve; it communicates by a branch 48 (shown only in Fig. 3) with the annulus 25 of the pertaining fuel conduit 24.

The inlet nipple 6 communicates, via a conduit, with an accumulator (not shown) supplied with liquid at high pressure by a suitable pump (such as the well known Deri pump); and the outlet or return nipple 7 communicates via a conduit with a sump or reservoir (not shown) from which liquid is supplied to the pump. Be tween the pump and the reservoir there is an over-pressure, spring-load relief valve to ensure substantially constant pressure of the liquid in the accumulator.

In practice the described device is suitably mounted on the engine and the shaft 16 is arranged to be driven from the engine at half the speed of the engine crankshaft in the case of a four-stroke cycle engine. Fuel is supplied to the fuel inlet nipple 4 by a low-pressure pump (not shown) driven by the engine, as is the pump for the supply of high-pressure pumping liquid.

It will be evident that fuel from the gallery 43 will tlow past the non-return valves 46 and via the bores 47 and ducts 48, 25, 26 to those of the fuel delivery conduits 24 in which the rear of the oating pistons 37 are not for the time being subjected to high pressure pumping uid, the fuel forcing back the floating pistons 37 in those conduits 24 against their abutments 32a. High pressure liquid from the aforesaid accumulator will ow, via the nipple 6 and duct 11 and annulus 10 to the duct 12 in the distributor 9. As 4this duct is brought to register with each radial duct .39 the high pressure liquid exerts pressure in the pertaining pressure fluid chamber 38 on the rear of the corresponding floating piston 37, whereby this piston is urged to the right in Fig. 1 forcing the fuel content of the conduit 24 past the non-return valve 27 to the pertaining fuel outlet nipple and thence to the fuel injector of the corresponding engine cylinder. The liquid pressure in the pressure chamber 38 is relieved when, on Con.-

tiouod rotation of the distributor 9, said faail doom9 is .placed in communication with the radial duct 40a leading passage portion 42a for the return flow of the .pumping liquid past the valve-like restriction 14a to a variable extent, thereby correspondingly varying the xtentof backward movement of the pistons 37 and consequently fthe amount of fuel admitted to the fuel conduits 24.

It will be seen that with the described arrangementfor metering the quantity of fuel the number of moving Lparts per fuel outlet is reduced to the minimum.

Clearances of the Working parts is not critical since .leakage past them dos not aiect the fuel metering.

Only small driving torque is necessary and this isfcoriJ The device can be made quite small in size and isfcapable of operation at speeds high enough 'for two stroke cycle as well as four stroke cycle internal lcombustion engines.

I'claii:

A device for injecting fuel into an internal combustion engine, comprising a body having at least one delivery conduit, at least one pressure liquid chamber, a movable partition separating the delivery conduit and the pressure liquid chamber from one another, passageways in the body including a non-return yvalve for supplying fuel under low pressur'eto .the delivery conduit, a vnon-rettifrn'valve controlling the outlet from the delivery conduit, a distributor rotatable in the body for controlling the periodic supply and discharge of a pumpingliquid at high -pressure to and from the pressure liquid chamberiareturn'ow passageway in the distributor for the pressure liquid, and a manually operable valvejcontrolling the outlet from said passageway thereby to limit each return stroke of the movable partition and Avariablfyv meter the quantity of fuel admitted on such stroke'to 'the 'delivery conduit prior to the expulsion of said fuel by the next forward stroke of said partition under the action of the high pressure pumpving liquid admitted to the high, pressure liquid chamber.

References ACited in the file of this `patent UNITED STATES PATENTS y2,406,296 Ield Allg. 20; 1946 2,484,884 Hanna Oct. 18,A 1949 2,531,332. Garday Nov. 2l, 1950 2,698,580 Evans Jan. 4, 1955 i i i i l t

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