US1076436A - Fuel-pump for internal-combustion engines. - Google Patents

Description

H. LEMP.

` FUEL PUMP FOR INTERNAL GOMBUSTION ENGINES.

APPLIOATION FILED 111mg, 1912.

Witnesses: 55 inventor-z v 52 Hermann Lamp) 'cierren inane ramena nien.

HERMANN LEM?, OF LYNN, MASSACHUSETTS, .ASSGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION GF NEW YORK.

FUEL-PUMP FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Cet. 21, 1913.

Application filed February 9, 1912. Serial No. 676,528.

pressure type wherein` the temperature ofA the compressed nir in the cylinder is utilized to lire the charge which admitted,` tol gether with an oil conveying charge of com-g pressed air, under the, control of a needle er other valve actuated by the cam shaft of the engine. l

The object of my invention is to provide a pump of impro/ved consti-action whereby the amount of oildeli.'ered to the engine can be closely and accurately regulated.

Briefly stated, my invention comprises a pump of the displacement type whose plunger has a constant length of stroke but whose region of movement is changed by positively and mechanically changing the position of the fulcrum of the plunger actuating lever. v

For a consideration of what I believe to be novel and my invention, attention is directed to the accoml'ianying specication and claims appended thereto.

'in dre/arccompanying drawing which illustrates one of the embodiments of my invention is shown an internal combustion engine with my improved fuel pump illustrated in section.

l indicates an internal combustion engine of any suitable construction and having as many cylinders as may be desired. The engine is more especially intended for use-1 with heavy fuel oils vand operates .at conf' stant pressure. v

2 indicates an upright governor shaft which is driven by 'suitable gearing from the main shaft of the engine, lnot shown. On the upper end of the shaft is a speed governor 3 of any suitable construction having a sliding collar Whose! position is changed by the Weights of the governor.

5 indicates a governor lever that has a fixed fulcrum 6 and is actuated by the collar through pins 7.A Mounted on the verti- "actuating lever 16.

cal governor shaft is a gear 8 that meshes with a gear i), both shown in dotted lines, said gear Sl'driving'the cam shaft 10 which actuates `the engine valves in the ordinary manner. The gears are inclosed in a housing 1l. The shaft is carried by suitable bearings supported by brackets-12 fastened to the side of the engine. Mounted on the cam shaft is an eccentric 13 that is surrounded by an eccentric strap 141. To the strap is connected a rod 15, the lower end of which is pivotally connected to the pump y The veccentric rod 15 has a constant length of stroke or travel at all times and its movements bear a fixed relation to those of the cam and main shafts of the engine. The lever 1G is' provided with a fulcrum 17 made inthe form of an eccentric and mounted en the shaft 18, the latter being carried by suitable bearings supported by the bracket 19 attached to the engine cylinder. .y Mounted on the shaft 1S isa gear 2O which meshes with a rr ck 21, the latter being provided with a guide and holding means 22 carriedby the bracket 19. The rack is connected b'y an adjustable rod 23 to the free end of the governor' lever 5 so that' as the lever moves upand v'down the rack ,will be correspondingly moved,r thereby imparting angular motion to the eccentric. The ends of the rod 23 are screw threaded to enable the heads mounted thereon to beA ad- Jujsted to increaseor decrease vlthe effective length of the rod, suitable check nuts being'provided to lock the parts in position. turning the eccentric in/one direction or the other, the fulcrum of the lever 16 will be raised or lowered, thereby changing the region of reciprocation of the plunger 24 of the pump. As shown, the fulcrurn of the pump, lever is in its lowest position,

hence as the shaft 18 is turned `in a clockf Wise direction, the pivot of the fulcrum. will be gradually raised thereby shifting the region of reciprecation` of the pump plunger from its lowest to a higher posit-ion. The pump comprises a plunger 24; that is connected to the lever 15 by a pin 25 that moves in a slot 26 of the lever. The plunger reciprocates in a ycylinder' 27 that is located within theftank 28 and secured to the bottom wall thereof by means of a nut 29 Which clamps'the same-.in place.y The; cylinder is provided with one or more laterally extending ports 30 four being shown in the present engine. The cylinder' is provided with a discharge valve 31 that is normally pressed against its seat by a coiled compression spring 32, the latter being located in a screwthreaded plug 33.

-l-l indicates the pipe for conveying fuel under pressure to one of the engine cylinders. As shown, the fulcrum of the lever 1G is in its lowest position, and the driving eccentric 1,3 is, in about its mid-positie".1 so that as the right-hand end of the lever is depressed the fuel that is contained in the c vlinder 27 under the plunger is forced outward past the spring seated discharge valve 531. A t some point on the upstroke of the plunger, it uncovers to a greater or less eX- tent, the port or ports 30 and permits fuel to flow from the tank chamber into the cylinder.

In such a pump it is desirable to maintain a constant level of fuel in the tank. To this end a float 35 is provided that is located in a chamber 3G, the walls of which are integral with. those of the tank. A portion ot' the wall between the tank and float chamber is cut away to permit of the free flow of fluid from one to the other. Fuel is admitted to the float chamber by the pipe 87 under the control of a ball valve 38, the latter vbeing held against its seat by the pin 39 when the fue] level is at a maximum. When the level of the fue] in the tank reeedes from normal, the float moves downward and the pin 39 releases the ball valve and permits fuel to enter from the pipe 37. The lower end of the float is guided by a rod 40.

I have shown only one pump, but itis to be understood that the same may be duplicated. I prefer to use one pump for each cylinder of the engine. These pumps may all be actuated by the lever 16 if desired.

The operation mechanism is as follows: Assuming the load to be constant, the eccentric rod l5 'as it moves to and fro raises the plunger 24 on its upward stroke admitting fuel to the cylinder through the ports 30 and on the downward stroke of the plunger oil is forced through the discharge valve and pipe -l-l to the engine. lf now the load decreases accon'ipanied by an increase of speed, the end of the governor lever 5 is moved upward.

carrying with it the rod 23 and the rack 21.. As the rod moves upward it turns the gear i() runl therefore the eccentric 17, thus raising the fulcrum of the pump actuating lever 16. This it will be observed has no effect on the movements of the driving eccentric 13, and eccentric rod 15. The ctiect, how ever, is to cause the pump plunger 24k to reciprocate between the two points which are somewhathigher than they were before, so that on the downward stroke of the plunger a greater distance isleft between itsflower of my improved pumpv end and the surface of the discharge valve 31. Hence less fuel will be discharged through said valve. A continued increase in speed will cause the fulcrum 17 of the pump lever to be raised to a higher point andthe effective stroke of the pump will be correspondingly'decreased. Conversely, if the speed decreases, the governor will move the rack 2l downwardly which results in turning the shaft 1'8 in an anti-clockwise direction thus lowering the position of the fulcrumof the pump actuating lever 1G.

In accordance with the4 provisions of the patent statutes, I have described the prin- 4 ciple of operation of my invention, together with the apparatus which I -now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

that I claim as new and desire to secure by Letters Patent of the United States 1s:-

1. An internal combustion engine in combination with a pump comprising a cylinder and a reciprocating plunger having a con'- stant length of stroke but variable region of reciprocation, a lever connected to the plunger, a driving means for vibrating one end of the lever through a fixed region, an

eccentric that forms the fulcrum for the lever,and a speed governor driven by the engine for turning the eccentric to change the region of reciprocation of the plunger without changing its length of stroke.

0.. An internal combustion engine, in comiin'affn with a pump of the displacement type comprising a cylinder having a lateral suction port therein, a plunger which re ciprocates in the cylinder and covers and uncovers the port on each stroke, said strokes being of constant length but of varying region, a ldischarge valve for the pump, a lever connected to the plunger, a driving means for imparting strokes of constant length to the lever, an eccentric forming a fulcrum for the lever, and a speed governor driven by the engine for turning the eccen` tric to change the region of reciproeation of the plunger.

2?. An internal combustion engine, in combination with a pump comprising a cylinder and a reciprocating plunger having a. constant lengijth of stroke but variable region of rcciprocation, a lever, a driving means connected to oneend of the lever for moving it back and forth through a tixedregion, an eccentric that forms the fulcrum for the lever and is located at its opposite end, means connecting the plunger to the lever at a point between the fulcrum and point of attachment of the driving means, and a speed governor' L driven by the engine for turning the eccentric on its support to eccentric that forms the fulcrum .for vthe lever, a speed governor driven'by the engine;

and a"connection between the, governor and the eccentric for inovmg the latter angularly which includes a rack and pinion.

An internal combustin engine, in 'com bination with a Vdisplacement pump comprising a cylinder and a reciprocating plunger having a constant length of stroke but variable region of reciprocation, a lever, an eccentric and rod driven by the engine and connected to lthe lever for Vibrating it, a fulcrum for the lever, comprising an eccentric, a speed governor, gearing connecting the governor and the eccentricl` for` turning it to change the region 0f vibration of the Goplee of this patent majlli'e obtained for tive cents each, by addressing the Commissioner ot Patents,

plunger, and a connection -between the plunger and the lever.

6. An internal combustion engine, in combination with a displacement pump comprising a ported cylinder and a reciprocating plunger loca-ted therein which covers and uncoversthe port, a discharge valve for the pump, a tank containing the cylinder which contains fuel Whose level is above that of the port, means for controlling the level of fuel in the tank, a lever connected to the plunger for actuating it, a driving means connected to the levez which moves `it t0 and fro in a fixed region, an eccentric form- -ing the fulcrum for the lever, a support therefor, a speed governor driven by 'the engine, and a means conveying movements of the governor to the eccentric for turning it in its support to vary the region of reciprocation of the pump plunger:

ln Witness whereof, I have hereunto set my hand this 8th day of February, 1912.

' HERMANN LEMP. Witnesses: f

ALEX. E. MACDONALD, BENJAMIN B. HULL.

Washington, D. e.

Images