US3288124A

US3288124A - Pump governor

Info

Publication number: US3288124A
Application number: US294495A
Authority: US
Inventors: Vernon D Roosa
Original assignee: HARTFORD MACHINE SCREW CO
Current assignee: HARTFORD MACHINE SCREW CO
Priority date: 1963-07-12
Filing date: 1963-07-12
Publication date: 1966-11-29
Anticipated expiration: 1983-11-29

Description

Nov. 29, 1966 v. D. ROOSA 3,288,124

PUMP GOVERNOR Filed July l2, 1963 4 Sheets-Sheet l ATTORNEYS Nov. 29, 1966 v. D. RoosA 3,288,124

PUMP GOVERNOR Filed July 12, 1963 4 Sheets-Sheet 2 INVENTOR. VERNON D. ROOS/ TTOR/VE YS Nov. 29, 1966 Filed July 12, 1965 V. D. ROOSA PUMP GOVERNOR 4 Sheets-Sheet 5 GEN.

FUEL TANK ENGINE INVENTOR. VERNON D. ROOSA ATTORNEYS V. D. ROOSA PUMP GOVERNOR Nov. 29, 1966 4 Sheets-Sheet 4 Filed July l2, 1963 INVENTOR. VERNON D. ROOSA wlw/? ATTORNEYS United States Patent Office 3,288,124 Patented Nov. 29, 1966 3,288,124 PUMP GOVERNDR Vernon D. Roosa, West Hartford, Conn. Hartford Machine Screw Co., R0. Box 1440, Hartford, Conn.) Filed July 12, 1963. Ser. No. 294,495 9 Claims. (Cl. 123-140) The present invention relates to fuel pumps conventionally employed for delivering fuel to an internal combustion engine, and more particularly to governing devices for regulating the fuel delivery of the pump It is a primary aim of the present invention to provide a new and useful isochronous governor having notable usefulness for regulating the fuel delivery of an engine fuel pump of the fuel injection type.

It is another aim of the present invention to provide an improved governor boost for the conventional governor employed in fuel injection pumps.

It is a further aim of the present invention to provide for an engine-driven generator installation, a novel governor having means for momentarily increasing the fuel delivery to the engine in anticipation of an increase in engine load occasioned by an increase in the electrical power supplied by the generator.

Another aim of the present invention is to provide an improved engine fuel pump of the type described having a novel governor boost which is adjustable for increasing or decreasing the usual droop in engine speed accompanying an increase in engine load.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplied in the construction hereafter set forth, and the scope of the application of which will be indicated in the appended claims.

In the drawings:

FIG. l is a longitudinal cross section view, partly broken away, of a pump incorporating a preferred embodiment of the governor of the present invention;

FIG. 2 is an enlarged top View, partly broken away, of the pump;

FIG. 3 is a partial section view taken substantially along line 3 3 of FIG. 2;

FIG. 4 is a partial section taken substantially along line 4-4 of FIG. 3;

FIG. 5 is a diagrammatic view of an engine-generator installation illustrating an aspect of this invention; and

FIG.. 6 is an enlarged longitudinal section view of a load anticipator of the governor.

Referring now to the drawings in detail, the fuel pump 10 exemplifying the present invention is shown to be of the type adapted to supply measured charges of fuel to the fuel nozzles of an internal combustion engine. A pump housing 12 having a housing cover 14 secured by fasteners 16 rotatably supports a pump rotor 18 and a connected drive shaft 20 having a tapered end for receiving a driving gear (not shown) to which the shaft 20 is keyed. A vane-type fuel transfer, or low pressure supply, pump 22 driven by the rotor 18 receives fuel from an engine fuel tank 23 (FIG. 5) via a filter 26 in the pump inlet 24 and delivers fuel under pressure via the axial conduits 28, 30 and annulus 31 to a pump metering Valve 32. A pressure regulator valve, generally denoted bythe numeral 34, regulates the transfer pump outlet pressure in accordance with the fuel requirements of the engine and returns excess fuel to the pump inlet 24. Conventionally, the transfer pump outlet pressure is regulated to increase with rotor speed and therefore with the speed of the engine with which the pump is associated.

A high pressure charge pump 36 driven by the rotor 18 comprises a pair of opposed plungers 38 reciprocable in a diametral bore in the rotor. The charge pump 36 receives metered fuel from the metering valve 32 via an annulus 40 and a plurality of angularly spaced radial passages 42 adapted for registration with a diagonal inlet passage 44 in the rotor 18. Fuel is delivered by the charge pump via an axial bore 46 in the rotor to a radial distributor passage 48 adapted for sequential registration with angularly spaced outlet passages 50 appropriately connected to the individual injection nozzles of the engine. A spring-biased delivery valve 52 in the axial bore 46 provides in a known manner for achieving sharp cutoff` of fuel to the nozzles and thereby eliminates fuel dribble to the engine combustion chambers. In the usual manner, the radial inlet passages 48 and the outlet passages 50 are located to ensure registration, respectively, with the diagonal inlet passage 44 during the intake stroke of the plungers 38 and with the distributor passage 50 during the discharge stroke of the plungers.

An annular internal cam 54 having a plurality of pairs of diametrically opposed camming lobes is provided for actuating the charge pump plungers 38 inwardly for delivering fuel to the pump distributor. A pair of rollers 56 and roller shoes 58 are mounted in radial alignment with the plungers 38 by a rotor driven carrier (not shown) for camming the plungers inwardly. For timing the distribution of fuel to the fuel nozzles with the engine operation, the annular cam 54 is angularly adjustable by a suitable timing mechanism 55.

A governor, generally denoted by the numeral 60, comprises a plurality of yweights 62 angularly spaced about the pump drive shaft 20 which, under the influence of centrifugal force, urge a sleeve 64 encircling the drive shaft 20 to pivot a governor plate 66, clockwise as seen in FIG. l, about a supporting rod 68. The governor plate 66 is urged in the opposite pivotal direction by a compression spring 70 having a bias which is made variable by an arm 72 controlled by a shaft 74 to which the engine throttle lever may be suitably connected. The governor plate 66 is connected for controllingthe angular position of the metering valve 32 by a control arm 76 fixed to the metering valve and a link 78 pivotally mounted on the control arm 76 and received within a bifurcated projection of the governor plate 66. A tension spring 77 attached to the governor plate 66 and tothe link 78 normally maintains the governor plate 66 in operative connection with the metering valve 32; however, a shutoff cam 79 suitably connected for operation by a lever mounted externally of the pump housing 12 is provided for angularly shifting the metering valve 32 against the tension spring 77 for shutting oif the fuel to the charge pump.

As is well known, the quantity or measure of the charge delivered by the pump is a function of the pressure of the inlet fuel to the charge pump 36. Therefore, by angularly adjusting the metering valve 32, the fuel pressure in the charge pump inlet and the measure of the charge delivered by the pump 36 can be controlled. The governor 60 will operate under the bias of the compression spring 70 to control the angular position of the metering valve 32, the measure of the charge delivered by the pump 36 and therefore the engine speed. However, an increase in engine load will normally produce a slight reduction or positive droop in the engine governing speed for any given throttle setting. This is due to the fact that the metering valve 32 must be opened to meet the increased fuel requirements of an engine under increased load, and, inasmuch as the governor directly controlsv the metering valve 32 the engine will necessarily stabilize at a lower speed. Of course, the reverse results when there is a decrease in engine load, i.e., the governing or stabilizing speed of the engine will increase.

In accordance with one aspect of the present invention, the pump governor 60'is provided with a governor boost or secondary control 82 `of the angular position Of the metering valve 32. As best seen in FIG. 3, the governor boost 82 comprises a support block 84 suitably secured within the upper cavity 80 of the pump housing 12 having a bore 86 reciprocably mounting a boost plunger 88. A limit stop 90 for the plunger 88 .is reciprocably mounted in an enlarged bore in the support block 84 for movement rearwardly from a shoulder 92 to a position adjustable by an elongated set screw 94 threaded to the housing 12. An inclined shoulder 96 is provided on the stop 90 for engagement by the set screw 94, and a forward projection 98 is provided on the stop for engagement with the plunger 88 to provide a fluid chamber 99 between the stop 90 and plunger 88. Passage 85 in the support block 84 and pump housing 12 provides communication between the fluid chamber 99 and the annulus 40 with the result that uid in the uid chamber between the plunger 88 and stop 90 urges the stop rearwardly against the set screw 94 and urges the plunger 88 forwardly. An O-ring seal 102 received within an annulus within the stop is provided for eliminating fuel leakage past the stop 90.

A rocker arm 104 is pivotally mounted by a pin 106 between a pair of upstanding sides 108 of the support block 84. A stop 110 threaded into one side of the support block is -received within a concave recess in the rocker arm 104 and thereby serves to limit the pivotal movement of the rocker arm. The rocker arm is operatively connected to the governor plate 66 by a partially spherical ball 112 xed to the governor plate 66 with a pair of fasteners 114 and received within a downwardly opening slot 116 in the rocker arm. The rocker arm is provided with a concave raceway 118 which is centrally recessed for retaining a follower or roller 120. The roller 120 is operatively connected to the plunger 88 for transmitting to the rocker arm 104 the force on the plunger 88 due to the fuel pressure in the fluid chamber 99. This connection comprises a rearwardly pointed guide 124 received within an inwardly tapered recess in the plunger 88 and having a central bore 126 receiving a rod 128. The rod 128 has a forward bifurcated end pivotally supporting the roller 120, and the guide 124 and rod 128 have opposed annular shoulders 130, 132, respectively, between which is compressed a coil spring 134 encircling the guide and rod.

A toggle linkage comprising a control link 136 mounted between the sides of the support block by a pivot pin 138, and a second link 140 mounted on the bifurcated end of the rod 128 by a pivot pin 142provide for adjusting the Iroller 120 along the raceway 118 of the rocker arm, for which purpose the pivotal connection between the guide 124 and plunger 88 is provided. A compression spring 144 is interposed between the support block 84 and the control link 136 to urge the roller 120 upwardly (as viewed in FIG. 3) along the raceway 118. A stop 146 threaded into the control link 136 for engagement with the support block 84 is adjustable for establishing the upper limit of travel of the roller 120 on the raceway 118, here shown with the longitudinal axis of the rod 128 and guide 124 adjustedk to a fixed position in which it intersects the pivotal axis of the rocker arm 104. An elongated set screw 148 is threaded to the housing cap 14 for fixing the adjusted position of the control link 136 against the bias of compression spring 144 and thereby position the roller 120 with respect to the pivotal axis of the rocker arm 104.

With the axis of the rod 128 passing above or below the axis of pin 106, the fuel or control fluid in the charnber 99 will therefore urge the plunger 88 forwardly to 4 s compress the compression spring 134 and thereby increase the bias on the rocker arm 104. With the toggle linkage adjusted to position the roller below the pivotal axis `of the rocker arm, or the axis of pin 106 (as viewed in FIG. 3), the bias on the rocker arm 104 will create a bias on the governor plate 66 urging the governor plate in the counterclockwise pivotal direction, as seen in FIG. 3, to increase the opening Aof the metering valve 32. With the toggle linkage adjusted to position the roller upwardly of the pivotal axis of the rocker arm 104, the rocker arm will urge the governor plate 66 in the clockwise direction, as seen in FIG. 3, in opposition to the compression spring 70 to decrease the opening of the metering valve 32.

The bias on the governor plate 66 provided by the governor boost 82 is dependent therefore upon the charge pump inlet fuel pressure as measured by the fuel pressure in the annulus 40 and the position of the roller 120 on the raceway 118 as adjusted by the set screw 148 for changing the mechanical advantage of the connection between the plunger 88 and rocker arm 104. It should be appreciated that for any given position of the metering valve 32, the charge pump inlet fuel pressure will decrease with increasing pump speed andtherefore with increasing engine speed, due primarily to the fact that with increasing speed there is a greater fuel flow and therefore a greater pressure drop across the metering valve 32. The charge pump inlet fuel pressure is also a function of engine torque inasmuch as the engine torque is directly related to the measure of the fuel charge delivered to the engine. Consequently, the bias on the plunger 88 provided by the metered fuel pressure and transmitted to the rocker arm 104 increases with decreasing engine speed and increasing engine torque.

A reduction or droop n engine speed with an increase in engine load can therefore be reduced or completely eliminated by appropriate adjustment of the position of the roller 120 below the axis of pin 106 with set screw 148 whereby the bias increase of the governor boost can be established to offset the normal speed droop, or where desirable to over or under compensate for the normal droop. With the roller 120 adjusted to a positio-n on the raceway 118 above the pivot axis of the rocker arm, :the normal droop of the engine will be increased.

In an engine installation where the engine 149 is mounted for driving an electrical generator 151, as show-n diagrammatically in FIG. 5, it is particularly desirable for the engine speed to remain constant over a range of engine loads and, therefore, over a range of electrical loads on the generator 151. As previously described, the toggle linkage would lbe appropriately adjusted to eliminate droop in the engine governing speed. However, it has been found that in the transition during which the engine load is increasing there will nevertheless be a slight drop in engine speed until the engine load is stabilized. As a consequence, the pump governor of the present invention incorporates a load anticipator 150 (FIGS. 5 and 6) which is responsive to an increase in the generator output and adapted to momentarily increase the fuel supplied by the pump to the engine 149 in anticipation of an increase in'engine load. This is accomplished in the preferred embodiment of the present invention by the incorporation of a plurality of current transformers 152 each sensitive to an increase in the genera-tor output supplied through a phase of the generator, -as where the generator provides a three phase output. These current I'transformers are electrically connected to three aligned coils 154 which encircle a nonmagnetic tubular cylinder 156, manufactured as of brass and having a pair of brass end connectors 158 threaded therein. Sleeves 160 provide for spacing the solenoids 154 on the tubular cylinder 156 a-nd a pair of O-rings 162 are provided for sealing the cylinder against leakage.

Also, `the outer connector 158 may be connected, as

. schematically shown in FIG. 5, for returning leakage to the fuel tank 23. v

Three magnetic armatures 164 separated by a pair of nonmagnetic tubular spacers 1'66 are reciprocably mounted within the tubular cyl-inder 156 and biased inwardly by a preferably nonmagnetic compression spring 168 interposed between an armature 164 and the outer tubular connector 158. A plunger 170 reciprocablymounted in the inner tubular connector 158 is engageable by the inner armature to urge the plunger inwardly. A passage 172 in the housing 12 (FIG. 1) provides for fluid communicat-ion between the plunger chamber and -the annulus 40 whereupon metered fuel pressure urges the plunger outwardly to compress the spring 168 and the load anticipator thereby acts in part as an accumulator to reduce fluid pressure fluctuations in the annulus 40.

If a change in the electrical output of the generator 151 should occur, a change in the flux produced by one or more of the transformers 152 will occur. This will cause the respective coils 154 to move toward the center of the flux field of their respective coils to aid the spring 168 in urging the plunger 170 inwardly and thereby momentarily increase the fuel pressure in the annulus 40 and i-n the plunger chamber of the governor boost. Consequently, the bias provided by the governor boost will, when the toggle link-age is adjusted for increasing the bias on the governor, momentarily increase the measure of fuel supplied to the engine 149 in anticipation of the increased engine load, and thereafter the normal governor and governor boos-t operation will take over. When the electrical load stabilizes, the plunger 170 and solenoid assume a balanced position determined by the fuel pressure in the annulus 40, the bias of spring 168 and centering force imposed on armatures 164 by the coils 154.

Thus, it can be seen that the governor boost of the present invention provides a secondary control of the metering valve of the fuel pump and Where desirable can be adjusted to offset the normal engine droop accompanying an increased engine load. Inasmuch as the governor boost allows for adjustability of the boost effect; none, partial complete or over compensation for the normal engine droop may be provided, or the engine droop may be increased. Further, with the load anticipator of the governor an increase in the engine load in an engine-driven generator installation can be anticipated to momentarily increase the fuel delivery to the engine prior to when the governor and governor boost would provide an increased fuel delivery.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

I claim:

1. In a fuel injection system for an internal combustion engine, a flyweight governor providing a primary control of the engine fuel supply, a control fluid having a pressure which is a function of engine speed, governor boost means responsive to the control fluid providing a secondary control of the engine fuel supply, and means for manually adjusting the secondary control of the governor boost means to provide a predetermined engine droop.

2. In a fuel injection system for an internal combustion engine, a flyweight governor providing a primary control Aof the engine fuel supply, said governor being operable under a bias controllable for varyingengine speed, governor boost means operable for changing the bias on the governor, said governor boost means being responsive to engine speed for increasing the governor bias with a decrease in engine speed, and means for manually adjusting the bias change of the governor boost means to regulate the droop of the engine.

3. In a fuel injection pump, a charge pump for supplying fuel to an associated engine of an engine-generator set,

a transfer pump for supplying fuel under pressure to the charge pump, a valve controllable for regulating the amount of fuel supplied to the charge pump, a flyweight governor operable under a bias for controlling the valve, governor boost means operable by the regulated fuel for changing the bias on the governor, and means responsive to a change in the load on the engine for adjusting the bias change of the governor boost means.

4. In a fuel injection pump, a charge pump for supplying fuel to an associated engine, a transfer pump for supplying fuel under pressure to the charge pump, a valve means controllable for regulating the amount of fuel supplied to the charge pump, a governor providing primary control of the valve means, governor boost means operable by the regulated fuel providing secondary con-trol of the valve means, and boost control means for modifying the secondary control of the governor boost means.

5. In a fuel injection pump for an internal combustion engine having a valve controllable for regulating the pressure of a control fluid, a pump for delivering fuel charges to the engine having a measure dependen-t upon the pressure of the control fluid, and a governor operable under a bias for controlling the valve, a governor boost comprising a pivotally mounted rocker arm, means operable by the regulated control fluid urging the rocker arm in one pivotal direction, and means operatively connecting the rocker arm and governor for changing the governor bias an amount which varies with the pressure of the regulated control fluid. i

6. In a fuel injection pump for an internal combustion engine having a valve controllable for regulating the pressure of a control fluid, a pump for delivering fuel charges to the engine having a measure dependent upon the pressure of -the regulated control fluid, and a governor operable under a bias for controlling the valve, a governor boost comprising a cylinder receiving the regulated control fluid, a plunger reciprocable in the cylinder biased in one direction by the regulated control fluid, a pivotally mounted rocker arm, means operatively connecting the plunger and rocker arm for transmitting -the fluid bias on the plunger into a pivotal bias on the rocker arm, means for effecting adjustment of the mechanical advantage of the connecting means, and means operatively connecting the rocker arm and governor for changing the governor bias.

7. In a fue-l pump for an internal combustion engine having a valve controllable for regulating the pressure of a control fluid, a pump for delivering fuel charges to the engine having a measure dependent upon the pressure of the control fluid, and a governor operable under a bias for controlling the valve, a governor boost comprising a cylinder receiving the control fluid, a plunger reciprocable in the cylinder biased in one direction by the control fluid, a guide pivotal-ly connected to the plunger, a pivotally mounted rocker arm with a raceway, a roller engageable with the raceway slideably connected to the guide compression spring means biasing the roller against the raceway and the plunger in the opposite direction, means operatively connecting the rocker arm and governor, and means for pivotally adjusting the guide.

8. The governor boost of claim 7 further comprising means for effecting adjustment of the bias of the compression spring means on the roller.

9. In a fuel pump for an internal combustion engine having a valve controllable for regulating the pressure of a control fluid, a pump for delivering fuel charges to the engine having a measure dependent upon the pressure of the control fluid, and a governor operable under a bias for controlling the valve, a governor boost comprising a cylinder receiving the regulated control fluid, a plunger reciprocable in the cylinder biased in one direction by lthe control fluid, a pivotally mounted rocker arm with a raceway, a roller engageable with the raceway pivotally connected to the plunger, means opera-tively connecting the rocker arm and governor, and manually adjustable toggle link means References Cited by the Examiner UNITED STATES PATENTS Links 123-140 Schick 123-140 X Eiler 290-40 HQfer 123--40 10 Giraudon 123-40 Schmidt 12S-140.3 vBcrgslen 290-40 Kleebergerf' 123-140 MARK NEWMAN, Prm'izzfy Examiner.

ORIS L. RADER, Examiner. 1

G. SIMMONS, L', M. GOODIUDGE,v v

Assistant Examiners.

Claims

1. IN A FUEL INJECTION SYSTEM FOR AN INTERNAL COMBUSTION ENGINE, A FLYWEIGHT GOVERNOR PRO VIDING A PRIMARY CONTROL OF THE ENGINE FUEL SUPPLY, A CONTROL FLUID HAVING A PRESSURE WHICH IS A FUNCTION OF ENGINE SPEED, GOVERNOR BOOST MEANS RESPONSIVE TO THE CONTROL FLUID PROVIDING A SECONDARY CONTROL OF THE ENGINE FUEL SUPPLY, AND MEANS FOR MANUALLY ADJUSTING THE SECONDARY CONTROL OF THE GOVERNOR BOOST MEANS TO PROVIDE A PREDETERMINED ENGINE DROOP.