US1181797A

US1181797A - Fuel-pump.

Info

Publication number: US1181797A
Application number: US87682814A
Authority: US
Inventors: Otto F Persson
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1914-12-12
Filing date: 1914-12-12
Publication date: 1916-05-02
Anticipated expiration: 1933-05-02

Description

O. F. PERSSON.

FUEL PUMP.

APPLICATION msn 959.1151914.

1 1 8 1 ,797 Patented May 2, 1916.

3 SHEETS-SHEET l.

F'icgl.

U To Governor' Otto P. Pe mason,

Patented May 2, 1916.

3 SHEETS- SHEET 2.

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FUEL PUMP.

APPLICATION FILED DEC.I2, I9I4.

To Govern or` F`i g. 5.

IN I N .I

Inventor-z Otto I`. Persson, @www Hsqttormgg.

Patented May 2,1916.

`SSIIEETS-SHEET 3. F ETREIKE ND LEAD. HALF n/ (Hlm. II I II III U i o Il I IIIIIIIIIITIIIIII Witnesses:

UNTTED STATES PATENT oEEioE.

OTTO F. PERSSON, OF ERIE, PENNSYLVANIA, ASSIGNOR'TO GENERAL ELECTRIC COMPANY, A. CORBORATION OF NEW YORK.

FUEL-PUMP.

Specification of Letters Patent.

. Patented May a, 1916.

Application filed December 12, 1914. Serial No. 876,328.

To all whom 'it may concern Be it known that I, OTTO F. PERssoN, a 4citizen of the United States,1'esiding at Erie, county of Erie, State of Pennsylvania, have invented certain new and useful Improvements in' Fuel-Pumps, of which the following is a specification.

The present` invention relates to fuel pumps, and particularly to those employed for supplying crude oil to internal combustion engines of'the high compression type; z'. e., those engines in which air is com pressed in the cylinder to a. temperature above the igniting temperature o-f the fuel and into which the fuel is introduced vby a suitable injector' operating with compressed air or other suitable means.

The invention relates more particularly to fuel pumps of the displacement type 1n' which the effective stroke of the pump is controlled by adjusting the fulcrum of the actuating lever for the plunger or plungers by lneans of fluid pressure., and its object is to provide an improved arrangement for this purpose.

For a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and the claims appended thereto.

Referring to the drawings which illustrate an embodiment of my invention, Figure 1 is a view partly in elevation and partly in section of a fuel pump; Fig. 2 is a sectional view showing the fulcrum adjusting means and controlling mechanism therefor; Fig. 3 is a sectional plan view of the same taken on line 3%3, Fig. 2; Fig. 1 is a side elevation of the pump, a part of the regulator mechanism being Shown in section; Figq is a sectional view through the fulcrum adjusting portion of the pump; Fig. 6 is a dia grammatic view illustrating the operation of the pump; Fig. 7 is a descriptive table of the operation as illustrated in Fig. G; and Figs. 8, 9 and 10 are detail views showing the position of the regulator for the pump under conditions of light load, half. load, and full load respectively. y

In the drawings, llrindicates the pump casing which in use'will be suitably connected to the engine frame by the flange 12. 13 indicates the main crank shaft of the engine, and 14 a crank thereon which operates the pump through connecting rod 15.

This crank may also operate a suitable lubri eating device 16 by means of the rod 17 joined to connecting rod 15. Fromthe lubricating device, pipes 18 convey lubricant to the various parts of the engine. The pump casing is provided with a. partition 19 which divides it into two compartments 2O and 21. The compartment 20 contains the immediate fuel supply for the pump. It is lfilled through the pipe 22 which mayv connect with any suitable main source of supply as with a tank placed at an elevation Vdischarged from the cylinders through the discharge pipes 26 which connect with suitable fuel injectors or other means on the engine for introducing the fuel into the engine cylinder. The pipes 26 have suitable discharge valves therein, as shown at 27 in Fig. 6. The pump plungers are operated on the down or discharge stroke by the cross-head 28, and on the up stroke by the springs 29 which act against the heads 30 on the upper ends of the plungers. The

cross-head 28 is not fastened to the plungers but only rests on them. It comprises a central cross piece carrying hollow members 31 at its ends which engage the heads 30 of the plungers. Arranged above and projecting through the hollow members 3l with their ends resting on the pump plunger heads 30 are the rods 32. These rods are normally held in the position as shown in Fig. 1 by the springs 33. On the top of the rods are handles 34 by which they may be manually forced downward to operate the pump plungers independently of the'cross heads 28. By means of these rods the pump may be operated to fill the pipes leading from it to the engine before the engine is started. At such times the rods 32 pass down through the hollow members 31 forc- Lierre? pump plungers by means of a lever made up of the two arms 35, the right-hand end of which is pivoted on an adjustable fulcrum 36 and the left-hand end is attached to the connecting rod l5. The connection between the arms and the cross-head 23 comprises a pair of links 37 (Figs. l and 5), the lower ends of which have trunnions 38 which engage in openings in the arms 35, andv the upper ends of which have bearings into which extend the trunnions 39 carried by a sleeve 40 which is clamped between the cross-head and a shoulder on the guide member 4l which is carried by the cross-head. This Jforms a pivotal link connection be`t tween the arms 35 and the cross-head. The guide member 4l is a piston like member which moves in the stationary guide 42 formed in or carried by the pump casing.

In operation the lever arms 35 are oscillated on the fulcrum 36 through the connecting rod 15 operated by the crank 14. This imparts a constant length of stroke to the plungers 24. When the plungers are at the upper end of the stroke, fuel flows freely into the pump cylinders 23 through the openings 25. 0n the discharge stroke fuel will be forced'back out of openings 25 until the lower ends of'the plungers reach the bottom edge of the openings 25, after which the fuel will be forced out through the discharge' pipes 26. From this it will be seen that the amount of fuel delivered through pipe 26 on any stroke of the pump will depend upon the distance which the ends of the plungers move below the openings 25. l`lhe plungers in the present instance have a constant length ot stroke as already stated, and the amount oit fuel delivered is regulated by varying the region of reciprocation of the plungers. This is accomplished by adjusting the position of the fulcrum 36 by means of the following arrangement.

Connected to the cross-head and moving therewith and with the guide member is a plunger 43 which operates in the cylinder 44. For eonveniencethis plunger and cylinder 1nay be termed the ulcrum adjusting pump. It is used to create a fluid pressure for adjusting the uicrum 36. This fulcrum adjusting pump is preferably arranged in the chamber 21. lt is provided with a suction valve 45 and a discharge valve 46. On the suction stroke of the plunger 43 Huid is drawn from'the chamber 2l through the suction valve 45 into the cylinder 44, and on the discharge stroke the fluid is delivered past the discharge valve `used in the fulcrun" 46 into the pipe or enduit 47. The fluid hinting pump will preferably be lubricr Si :g oil, and the oil for lubricating the engiil as 'well as that used in the fulcrum adjusting pump may be taken from this supply. The discharge pipe 47 of the ulcrumadjusting pump leads to the upper end. of 'a cylinder 48 in which is a piston 49 connected at its lower end to the fulcrum 36. The position and movement of this piston in the cylinder and hence the position of the fulcrum 36 depends upon the pressure delivered to the cylinder 48 by the fulcrum adjusting pump. This pressure acts in opposition to the spring' 50 which pushes the fulcrum 36 upward. 'lhe fulcrum adjusting pump operates continuously in synchronisin with the pump plungers 24 so that so long as the engine is ruiming the same will be creating a pressure in the cylinder 48. This pressure and hence the position of the ulcrum is regulated by shunting or ley-passing a greater or lesser amount of the luid being pumped around the cylinderby means of the by-pass pipe 51. This by-pass pipe terminates in a short section of engages the seat 57.

formed through the wall of the pipe section pipe 52 arranged in casing 53 bolted over an openingv 54 in the-side of the pump casing. rlhe front of the casing is preferably glazed 'so that the parts inside it may be observed. The short section 52 is in substance the end of pipe 51, although in actual practice it is preferably made as a separate piece. extending across the casing 53 and connected to pipe 51 by a suitable Anipple The end of the pipe section 52 is closed by a needle valve 56 which, when screwed down, in opening ,'58 is 52 adjacent to the seat 5'?. When the needle valve is screwed backv from its seat the interior of the pipe is connected through this openih'g 58 with the interior of the casing 53. rlrranged inside casing 53 and surroiuiding the pipe section are two

concentric sleeves

59 and 60. Between the inner sleeve 59 and the pipe section 52 is formedto connect the interior thereof with Athis space. The inner sleeve 59 is provided with an opening 63 which is preferably in the same plane with openings 62, and the outer sleeve is provided with an elongated slot 64 in the saine pla'ne with opening 63. The two

concentric sleeves

59 and 60 are adapted to oseillate relatively to each' other and to the pi section 52 to bring the

openings

63 and 64 more or less into alinement. Grin other words. 'the outer sleeve covers the opening 63 in the inner sleeve and the movement of the two sleeves acts to uncover it to a greater or less extent. The sleeves are oscillated, one by the movements of 'the adjustable fulcrum 36 and the other by the governor of the engine. To this end the inner sleeve is connected with the fulcruni 36 by an arm 65 and linl: 65al and theouter sleeve is connected with the speed governor rod 66 'through the arm 67 and links 68. lt `will be understood that the governor rod 66 will lli' r60. In other words,

be connected with the governor of the engine in the usual manner.

Referring particularly to Figs. 6 to 10, the operation of my invention will be described. In Fig. 6 the

sleeves

59 and 60 are shown in the position they assume when the engine is at rest. The adjustable fulcrum 36 is at its highest point and the speed governor rod 66 is at its lowest. The opening 63 through the inner sleeve 59 is out of registry with the slot 64 in the outer sleeve the sleeve 6() covers opening 63. As soon as the engine is started the crank 14 on the shaft 13 will operate the fuel pump plungers 24 through the arms 35 and cross-head 28. At the same time the fulcrum adjusting pump will begin to operate Aand create a fluid pressure on the piston 49. As already stated the fuel pump is of the displacement type, the fuel flowing freely into the cylinders Q3 through openings 25 on the suction stroke and being forced therefrom on the discharge stroke, the amount of fuel delivered on any stroke depending on the distance which the end of the plunger moves below. the openings 25, which in turn depends upon the position of the adjustable fulcrum 36. The distance IV (Fig. 6) indicates the length of stroke. I indicates the beginning of the stroke at no load, and V the position of the fulcrum at no load. From this it will be seen that with absolutely no load the pump delivers no fuel, the stroke of the plunger terminating at the lower edge of openings 25. So soon as the pump starts the pressure created by the fulcrum adjusting pump will build up and tend to lower the fulcrum 36. This tends to oscillate the sleeve 59 in an anticlockwise direction and to move the opening 63 therein into registry with slot 64 so as to uncover it. At the same time the speed governor rod 66 tends to oscillate the outer sleeve 60 in a clockwise direction to uncover the opening 63. In other words, there is a movement of the opening and slot toward each other. As the fulcrum 36 lowers fuel will be delivered to the engine in gradually increasing amounts. This will build up the speed of the engine. When a predetermined relation between the speed and the load is reached, the adjustable fulcrum and the governor rod will have been moved to uncover opening 63 to a greater or less extent. lVhen this occurs a. certain amount of the fluid pressure created by the fulcrum adjusting pump will be by-passed around the cylinder 48 by way of pipe 51,

openings

62 and 63, and slot 64, the fluid escaping into casing 53 from whence it may flow through opening 54 in the casing 11 to the crank case of the engine or other suitable point so as not to be wasted. The governor will then assume control and will regulate the esca pc ci fluid pressure from opening 63 so as to maintain the fulcrum in such a position that the correct amount of fuel will be delivered to hold the engine speed at the desired value. Should the speed decrease for any reason, as due to increase of load, the governor rod will lower, oscillating the outer sleeve 60 in an anti-clockwise direction to cover the opening 63 slightly more. This will result in a lesser amount of fluid pressure beingv by-passed and in a greater pressure on the piston 49 which will be lowered thus lowering the fulcrum 36 and increasing the effective stroke of the pump, causing it to deliver more fuel to the engine. At the same time, when the fulcrum lowers it will oscillate the inner sleeve 59 in an anti-clockwise direction, thus tending to move opening 63 to cause it to be uncovered. This insures a quicker compensation for load changes and at the same time tends to prevent over regulation orhunting7 Should the engine speed increase, the movements of the regulator would be the same only in the opposite sense.

The Roman numerals II, III a; l V7 VII in Fig. 6 indicate the beginning of the stroke and the position of the adjustable fulcrum respectively, at half-load and full load,7as pointed out in the explanatory table Fig.

Figs. 8, 9 and 1() show the relative positions of the regulating parts at light load, half-load and full load respectively. In each position it will be seen that the outer sleeve 60 is in position to regulate the escape opening 63 to maintain the engine at the speed corresponding to that load.

y 'hen it is desired to stop the engine, the needle valve 56 may be screwed away from its seat, thus letting the pressure quickly escape through the opening 58 and the fulcrum assume the no-load position.

While I have specifically described my invention as used in connection with a pump of the displacement type having a constant length of stroke, which is the arrangement I now prefer, it will be understood that it is not necessarily limited thereto, but can, if found desirable, be used in connection with other types of pumps.

In accordance with the provisions` of the patent statutes, I have described the principle 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.

vWhat I claim as new and desire to secure by Letters Patent of the United States, is,-

1. The combination with a fuel pump having a working cylinder, a plunger, an actuator for one of said parts having a fulcrum, and a pressure sensitive means for adjusting the fulcrum, of means for supplying fluid under pressure to said pressure vsensitive means, and means for regulating such supply comprising two concentric cylindrical members adapted to oscillate relatively to each other and provided with openings which register to permit the escape of fluid.

2. The combination with a fuel pump having a working cylinder, a plunger, an actuator for one of said parts having a fulcrum, and a pressure sensitive means for adjusting the fulcrum, of means for supplying fluid under pressure to said pressure sensitive means, and means for regulating such supply comprising a governor rod, and two cencentric cylindrical members adapted to oscillate relatively to each other and provided with openings which register to permit the escape of fluid, one of said members being connected to the fulcrum and the other to said rod.

3. The combination with a fuel pump having a working cylinder, a plunger, an actuator therefor having a fulcrum, and means adapted to be actuated by fluid pres sure to adjust the fulcrum, of means operated in synchronism with the pump plunger for supplying fluid under-preure to the fulcrum adjusting means, a by-pass around said last-named means, and means for controlling the escape of .fluid through said bv-pass comprising concentric members adapted to oscillate relatively to each other and provided with openings which register to permit the escape of fluid, and means for adjusting the position of said members relatively to each other.

4. The combination with a fuel pump having a working cylinder, a plunger, and

an actuator for one of said parts having an adjustable fulcrum, of a movable abutment for adjusting the fulcrum, means for supplying fluid under pressure to said abutment, a pipe for by-passing fluid around the abutment, and means for controlling the passage of fluid therethrough comprising two concentric members adapted to oscillate relatively to each other, the inner having an opening communicating at all times with said pipe and the outer having an opening adapted to communicate with the opening in the inner member, and means for adjusting the positions of said members relatively to each other.

5. The combination with a fuel pump having a working cylinder, a plunger, and an actuator for one of said parts having an adjustable fulcrum, of a movable abutment for adjusting the fulcrum, means for supplying fluid under pressure to said abutment, a pipe for by-passing fluid around the abutment, and means for controlling the passage of fluid therethrough comprising two concentric members adapted to oscillate relatively to each other, the inner having an opening communicating at all times with said pipe, and the outer having an opening adapted to communicate with the opening in the inner member, means connecting one of said members to the fulcrum, and means for adjusting the other member relatively thereto.

6. The combination with a fuel pump having a working cylinder, a plunger, and an actuator for one of said parts having an adjustable fulcrum, of a movable abutment for adjusting the fulcrum, means for supplying Huid under pressure to said abutment, a pipe for by-passing fluid around the abutment, and means for controlling the passage of fluid therethrough comprising a member concentric with and movable relatively to the end of said pipe and having an opening through which fluid may escape therefrom, a second member concentric with the first and adapted to move relatively thereto to cover and uncover said opening, means connecting one of said members to the adjustable fulcrum, a governor rod, and means connecting the other to the governor rod.

7. The combination with an internal combustion engine, of a pump for supplying fuel thereto comprising a cylinder, a plunger therefor, an actuator for the plunger having an adjustable fulcrum, pressure operated means for adjusting the fulcrum, a pump operated by the engine for supplying fluid under pressure to the fulcrum adjusting means, and means for regulating suchsupplycomprising two concentric cylindrical members adapted to oscillate relatively to each other and provided with openings which register to permit the escape of fluid. In witness whereof, I have hereunto set my hand this ninth day of December, 1914.

OTTO F. PERSSON. Witnesses: l

NELSON J. DARLING, LEO V. S'roELTzLEN.

Copies of this patent may be obtained for ve cents each, by addressing the "Commissioner of Patents. Washington. D. C.