US2742888A - Governor controlled metering valve for fuel pumps - Google Patents

Description

April 24, 1956 v. D. ROOSA 2,742,888

GOVERNOR CONTROLLED METERING VALVE FOR FUEL PUMPS Filed April 4, 1952 I so JIIIIFIF J I 94 2Q 54 55 4,0 II

1 v 66 7@ M 74 7a 70 5,2 90 36a 11 4 r; /Q m H. Fl w i I m6 INVENTOR. VERNON D POOJA A TORNE Y5 United States Patent GOVERNOR CONTROLLED METERING VALVE FOR FUEL PUMPS Vernon D. Roosa, West Hartford, Conn. Application April 4, 1952, Serial No. 280,574 13 Claims. (Cl. 123-140) The present invention relates generally to fuel pumps and is concerned, more particularly, with a novel and improved arrangement for providing a governor controlled metering valve in a fuel pump of the type employed for delivering fuel to an internal combustion engine.

In the use of internal combustion engines it frequently is desirable to regulate the flow of fuel to the engine responsive to engine speed this being the case, particularly, where constant speed operation is desired. Heretofore, arrangements for controlling the operation of the fuel pump by an engine driven governor have been generally cumbersome and complicated and inconvenient and difiicult to install, as well as expensive and difficult to fabricate and assemble. Moreover, such arrangements are frequently inefficient in operation, lacking in sensitivity and responsiveness and subject to error in adjustment and function.

An object of the present invention is to provide a governor controlled metering valve which is composed of a minimum of parts and which parts are of simple construction and design so that they may be easily and economically fabricated and assembled.

A further object of the invention is to provide such an arrangement where the operation is simple and efiicient providing a highly accurate speed responsive metering action from which mechanical error has been substantially eliminated and which will function etliciently and reliably over long periods of time without repair and replacement.

Another object of the invention is to provide a governor controlled metering valve arrangement for fuel pumps which is simple and easy to install, which is adaptable for installation universally in a wide variety of engine designs, and which permits of variation in the relative placement of the elements to compensate for variations in conditions and for adjustment purposes.

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

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified 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. 1 is a fragmentary and partly diagrammatic view of an embodiment of the invention installed on an engine, some of the elements being cut away to show certain of the operating parts, and

Fig. 2 is an enlarged fragmentary view partly in cross section showing details of the metering valve and push rod construction.

Referring to Fig. 1 of the drawings, the engine block of an internal combustion engine is shown diagrammatically at 10. Mounted on a pad or abutment 12 thereof as by bolts 14 is a fuel pump indicated generally by reference numeral 16. Also mounted on the engine is a conventional governor indicated diagrammatically at 18. g The details of construction of the fuelpump 16 form in part pointed the pump unit is placed 2,742,888 Patented Apr. 24, 1956 no part of the present invention and therefore the description will be limited solely to such features as may warrant explanation to assist in the understanding of the present invention. The fuel pump 16 as illustrated is generally similar in design to that disclosed and claimed in my co-pending application Serial No. 767,939, filed August 11, 1947, now Patent No. 2,641,238, issued June 9, 1953.

The fuel pump lower housing 20 16 comprises a generally cylindrical in which is telescopically received a pump body 22. The pump body 22 has an axial bore 24 (see Fig. 2) in which is rotatably mounted a fuel distributing member 26. The fuel distributing member 26 is adapted to be driven by the engine by a shaft or other means (not shown) extending within the pad or abutment 12 of the engine.

The lower end of the fuel distributing member 26 carries a pump unit indicated generally at 28 including a piston 30 which is actuated intermittently, as the fuel distributing member 26 is rotated, by a stationary cam 32 and roller assembly 34. Without going into details of construction which are outside the scope of the present invention, suffice it to say that the operation is such that fuel admitted to the diagonal passageway 36 (see Fig. 2) is intermittently admitted to the pump unit 28 as the fuel distributing member 26 is rotated and then alternately in communication in sequence with outlet couplings 38. In a complete installation, of course, the outlet couplings 38 are connected individually by flexible conduits or tubing with the various engine cylinders.

Mounted at the top of the pump body 22 is a pickup pump indicated generally at 49 which may be of the vane or gear type, for example, and which is driven by connection with the fuel distributing member 26. The pickup pump 40 has an inlet coupling 42 adapted to be connected to a fuel storage tank (not shown) and an outlet at 44 which may be connected by internal passageways or La combination of internal passageways and outside tubing with the annular groove 46 formed in the fuel distributing member 26. By way of the groove 46 the fuel transmitted by the pickup pump 40 enters the enlarged transverse passageway 48 which intermediate its ends communicates with the diagonal passageway 36 previously referred to.

The mechanism of the present invention is-intended to provide a metering of the fuel flow from the transverse passageway 43 into the diagonal passageway 36 responsive to engine speed. The aim of rendering the metering responsive to engine speed is the reason for the presence of the governor 18 previously referred to. The governor 18 may be of any conventional design and of the various types provided by engine manufacturers. For that reason the governor 18 is shown only diagrammatically it being essential only that the governor include a movable member such as the arm 50 pivoted at 52 which is subjected to a pivoting force such as by centrifugally operated weights which force varies with engine speed. In the illustration in the drawing, the arm 50 is urged in a counterclockwise direction by a force proportional to engine speed. The mounting for the governor is independent of that for the fuel pump and spaced therefrom.

In accordance with the invention, the metering of the fuel flow from passageway 4-8 into passageway 36 is obtained by means of a freely mounted piston or plunger 60. As illustrated, the piston 60 may comprise nothing more than a suitably finished piece of round bar stock inserted into the passageway 48. When the piston 60 is in the position shown in Fig. 2 of the drawings, the passageway 36 is wide open permitting maximum fuel fiow. As the piston is moved to the left from the position shown, the effective opening to passageway 36 is progressively closed off by the piston thus decreasing the fuel flow. The piston is biased toward the position shown in Fig. 2 when the pump is in operation by reason of the fact that its face or forward end indicated at 62 is subjected to the pressure of fuel within the passageway 48.

Turning now to the connection between the metering valve and the governor, it will be observed that the housing 20 is provided with a boss 64 exterior to the passageway 48 and provided with an enlarged tapped opening 66. Threadably, and therefore adjustably, received in the tapped opening 66 is a bushing 68 formed with a polygonal head 70 to facilitate adjustment. The bushing 68 has a through passageway 72 characterized by an arcuate front bearing surface 74 of restricted diameter, a central enlarged portion 76, and a flared entranceway 78.

A push rod having a necked down end portion 82 is inserted within the bearing '74 so that the rounded end 84 abuts against the outer end of the piston 60. The push rod is of sufficient length so that its opposite end will extend through the opening 86 of the governor housing 88, the opposite end being necked down as at 90 and being received in ball and socket fashion within the generally conical depression 92 of the head 94 fixed to the end of the governor arm 50 previously referred to. To keep dirt out of the mechanism a flexible boot 96 of the bellows type is attached between the rod 80 and boss 64, while a second boot 98 is similarly attached between the rod 80 and the housing 88.

As previously mentioned, the governor 18 is of a conventional type in which the arm 50 is urged in a counterclockwise direction with varying force depending on engine speed. The balancing and restoring force on the governor is provided by a spring 100 attached at one end to a bracket 1G2 fixed to the push rod 80 and attached at its other end to a bent rod 104 adjustably mounted on the engine block. Accordingly the push rod 80 will shift axially back and forth in response to engine speed, its position being determined by a balance between the restoring force of spring 100 and the force exerted by the governor arm 50.

As will be apparent, when the push rod 80 is shifted axially to the left as viewed in the drawings which occurs upon increased engine speed, the rod 80 will bear against the outer end of the piston 60 and force it inwardly thus decreasing the flow of fuel to the engine causing a correction of the engine speed. Conversely, when the engine slows down causing the push rod 80 to be shifted to the right, the plunger 60 is permitted to move outwardly of the passageway 48 under the influence of fuel pressure, thus increasing the effective opening to passageway 36 and transmitting more fuel to the engine.

As is customary with conventional governors the spring 106 is a relatively heavy or strong spring and during operation of the engine throughout most of its speed range the additional restoring force applied by fuel pressure on the end of piston 60 which is transferred in turn to the push rod is negligible and may be ignored. However, when the engine is operated at or near its idling speed the force exerted by the governor arm 50 becomes so slight that the force exerted by fuel pressure on piston 60 is relatively large and will prevent proper idling of the engine. For that reason I have found it desirable to include an auxiliary or compensating spring 106 of light construction between the bracket 102 and the engine block in opposition to spring 100.

An important feature of my invention is the ease and simplicity with which the operational characteristics of the valve are determined and adjusted. As shown in Fig. 2, the piston 60 is of sufficient length so that when it is in metering position it can extend outwardly into the opening 66 in the boss 64. The axis of the opening 66 and hence the bushing 63 is generally parallel to that of the passageway 48 but they are not co-axial, the axes being offset an appreciable distance. As a result the inward movement of the push rod 80 is effectively and safely limited by abutment of the end of the push rod against the outer surface of the pump body 22 and the limit of the outward movement of the piston 60 is effectively and adjustably fixed by engagement of the piston against the inner end of the bushing 68. As will be recalled, the threaded bushing 68 may be adjusted into and out of the threaded opening 66, thus varying the distance which the piston may move in an outward direction. A lock nut 108 may be provided to effectively hold the bushing 68 in adjusted position.

Because the passageway 48 communicates with the opening 66 and is closed only by the sliding piston 60, some leakage of fuel around the piston and into the opening 66 will occur during normal operation. For this reason, a downwardly extending groove 110 is cut in the interior surface of the housing 20 which will permit any fuel accumulating in opening 66 to drain into the lower part of the pump housing.

By reason of the flared passageway 76 in bushing 68 and the flared opening 92 in the governor arm together with the necked down formation of the end portions of the push rod which cooperate therewith, a substantial degree of misalignment is permitted without rendering the mechanism inoperative. This is important not only to take care of variations in mounting conditions but is essential in order to permit the fuel pump 16 to be turned about its vertical axis through an appreciable angle as desired to vary the timing of the pump.

It thus will be seen that the governor controlled metering valve of the present invention has many advantages of practical value as well as being of simple and economical design and effective for the intended purpose.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

I claim as my invention:

1. In a fuel feed system for internal combustion engines,

a fuel pump comprising a pump body having an outwardly opening fluid passageway subjected to fuel under pressure and having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, and means responsive to engine speed for controlling outward movement of the plunger comprising a governor, motion transmitting means between the governor and the plunger, a first spring connected to the motion transmitting means in opposition to the governor, and a lighter spring connected to the motion transmitting means in opposition to outward movement of the plunger.

2. In a fuel feed system for internal combustion engines, a fuel pump comprising a pump body having an outwardly opening fluid passageway subjected to fuel under pressure and having an orifice in the side wall thereof forming a fuel outlet, a plunger slidable endwise in said passageway across the orifice to vary the effective opening of the fuel outlet and being freely movable inwardly of the passageway, said plunger having a surface facing inwardly of the passageway whereby the plunger is urged outwardly from the passageway by fluid pressure therein, a governor responsive to engine speed, and a reversible drive connection between the governor and the plunger.

3. In a fuel feed system for internal combustion engines,

a feed pump, means forming an open-ended valve chamber having an inlet at its inner end communicating with the feed pump, a plunger slidable endwise in said feed chamber freely movable inwardly of the chamber and having a surface facing said inlet, said chamber having an outlet whose effective opening is increased by outward movement of the plunger, a control member engaging the outer end of the plunger and mounted for movement axially therewith, and means including a governor and an adjustable spring in opposition to the governor for biasing the control member in a direction inwardly of the chamber responsive to engine speed.

4. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway to increase the effective opening of said outlet responsive to fluid pressure in the passageway, a governor having an actuating element in approximately axial alignment with the plunger, and a rigid push rod mounted for axial movement in end abutting relationship between the actuating element of the governor and the plunger.

5. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a push rod, means slidably supporting one end of the push rod for endwise engagement with the outer end of the plunger, a centrifugally operated governor arm engaging the other end of the push rod, and adjustable spring means biasing the push rod away from the plunger.

6. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a push rod, guide means for one end of the push rod located adjacent the open end of the fuel passageway having an arcuate bearing surface to permit limited pivoting movement of the rod relative to the plunger, a centrifugally operated governor arm, and means forming a pivotal connection betweenthe other end of the rod and the governor arm.

7. In a fuel feed system for internal combustion engines, means forming an open ended passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the eifective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, a first spring opposing movement of the push rod and governor arm toward the plunger, and a second spring in opposition to the first spring compensating for the outward thrust of the piston due to fluid pressure at low engine speed.

8. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the eflective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, stationary stop means separate from the push rod limiting outward movement of the plunger, and stationary stop means separate from the plunger limiting opposite movement of the push rod.

9. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, and means offset from the axis of the passageway forming a sliding support for the end of the push rod.

10. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, means forming an enlarged chamber at the outer end of the passageway, and a bushing having a central opening forming a sliding support for the end of the push rod threadably received in said chamber.

11. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, means forming an enlarged chamber at the outer end of the passageway, and a bushing closing the outer end of the chamber having a bore for slidably receiving the end of the push rod, said bore being offset from the axis of the passageway.

12. In a fuel feed system for internal combustion engines, means forming an open ended fuel passageway having a fuel feed outlet, a freely mounted plunger slidable endwise in said passageway and adapted to vary the effective opening of said outlet, said plunger being urged outwardly from the passageway responsive to fluid pressure in the passageway, a centrifugally operated governor arm, a push rod extending between the governor arm and the plunger, means forming an enlarged chamber at the outer end of the passageway, and a bushing closing the outer end of the chamber and having a through opening for slidably receiving the end of the push rod, said through opening being outwardly flared and being provided with an arcuate bearing surface to permit limited pivoting movement of the push rod rela tive to the bushing.

13. In a fuel feed system for an internal combustion engine, a fuel pump comprising a pump body having an outwardly opening fluid passageway subjected to fuel under pressure and having a transverse fuel feed outlet, means forming an enlarged chamber at the opening of the passageway, a plunger freely mounted in the passageway and adapted to vary the effective opening of the fuel outlet, said plunger being urged outwardly from the passageway into the chamber by fluid pressure in the passageway, a bushing adjustably mounted in said chamber and closing the outer end thereof, said bushing having a through opening offset from the axis of the plunger, a push rod slidably received in said through opening, and a governor having a centrifugally operated arm connected to the push rod.

References Cited in the file of this patent UNITED STATES PATENTS 2,050,392 Starr Aug. 11, 1936 2,161,507 Egersdorfer June 6, 1939 2,378,036 Reggio June 12, 1945

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