US2145533A - Fluid transfer mechanism - Google Patents

Description

Jan. 31, 1939. Q STARR 2,145,533

FLUID TRANSFER MECHANISM Filed July e, 1956 s Sheets-Shed 1 INIENTOR 03cm! 1.. .STRRR BY Z a 5 ATTORNEY L. STARR FLUID TRANSFER MECHANISM Filed July 6, 1936 3 Sheets-Sheet 2 v 27 ?3' 3/ 3 4 23 32 a Q G 3E 1 1 3 r W 24 f 1 EIE E I if I 27 a! 2 %23 AQQZI Q 2 8 E:EI 3 Dag/K Y mm? ATTORNEY Jan. 31, 1939.

Filed July 6, 1956 3 Sheets-Sheet 3 EIE E 6 EIE 7 INVENTOR L. Smek ATTORNEY Patented Jan. 31, 1939 UNITED STATES PATENT OFFICE 2,145,533 FLUID TRANSFER MECHANISM Application July 6, 1936, Serial No. 88,997

4Claims.

My invention relates to fluid transfer mechanism, and more particularly to an improved fuel transfer pump for supplying fuel under pressure from a source of supply to the fuel injection 5 means of a solid fuel injection system for a compression ignition or the like engine.

In a solid fuel injection system for a compression ignition or the like engine employing a fuel injection pump which supplies fuel oil under extremely high pressure (over 1000 pounds per square inch), to a fuel injection nozzle actuated by the pressure of the fuel from the injection pump to spray fuel into the associated cylinder of the engine, it is desirable that low pressure fuel transfer means be provided between the injection pump and the source of fuel supply to insure an adequate supply of fuel for the fuel injection means at all operating speeds of the engine.

If such adequate supply of fuel were not provided, the engine would not operate properly, and air pockets would be apt to form in the fuel injection line which would prevent proper functioning of the fuel injection system. Such fuel transfer means is especially desirable in fuel injection systems for compression ignition engines on automotive vehicles, such as tractors, where it is impractical to provide an elevated fuel tank supporting structure on the vehicle, sufficiently high to insure that the fuel is supplied to the fuel injection means under a high enough gravity head for maintaining the fuel injection system solid with fuel at times. It is also desirable for some systems that the fuel transfer means be so constructed as to permit priming of the fuel injection system by gravity flow from the fuel tank should, for any reason, parts of the fuel injection system be disconnected and then reassembled.

The fuel transfer means or pump of my invention is designed to satisfy the foregoing described needs; and my invention has as its objects, among others, the provision in a fuel transfer pump or means for a compression ignition engine, solid fuel injection system of improved:

(1) Structural arrangement for providing an adequate fuel supply to the fuel injection means of the compression ignition engine at all operating speeds of the engine;

(2) Means for enabling priming of the fuel injection system with fuel without the provision of valves which have to be manipulated for this pur- D (3) Structural arrangement of economical and simple construction;

(4) Pumping means and valve means actuated thereby for supplying a quantity of fuel in excess of that required by the engine, and by-passing such excess quantity of fuel;

(5) Valve means operated by the pressure of the pumping means and which is of such construction as to be balanced by such pressure.

Other objects of the invention will become apparent from a perusal of the following description thereof. 10

In general, the fuel transfer means comprises pumping means connected in a feed passageway extending between a source of fuel supply, such as a tank, and the fuel injection means of a compression ignition or the like engine. The pumping means is connected to be driven by the engine, and consequently when the engine is operating, the pumping means is actuated thereby to feed fuel to the fuel injection means. However, when the engine is not turning over sufiiciently fast or 20 not at all and the pumping means is consequently inactive, it will not be operative to feed the fuel.

In a solid fuel injection system, it is essential that the fuel system be solid with fuel at all times, and consequently it is sometimes necessary to prime the system from the fuel source or tank independent of the action of the pumping means. This is especially necessary should parts of the fuel system be disassembled for any reason and then replaced. To obtain a. path for such priming, I provide a passageway independent of the pumping means, or in other words a passageway which extends past the pumping means, which is connected at both the inlet side and the outlet side of such pumping means. Thus, the priming passageway, when open, short circuits or shunts out the pumping means to allow gravity flow of fuel past the pumping means.

Ifsuch priming passageway were maintained open at all times and the pumping means were actuated, it is obvious that no fuel could be supplied to the fuel injection means. Heretofore, hand operated valve means was provided to close the priming passageway when the pumping means was to be actuated. To overcome the 45 disadvantages of hand operated valve means, which the operator sometimes forgot to close after opening thereof to allow the priming, I provide valve mechanism which normally uncovers or opens the priming passageway when 50 the pumping means is inactive, thus permitting priming automatically by gravity. However, upon actuation of the pumping means and when sufficient fuel pressure is created, the valve mechanism is automatically shifted or moved to close 55 tive.

the priming passageway and thereby allow the pumping through the feed passageway.

To insure an adequate supply of fuel, the pumping means is made' of such capacity as to pump normally more fuel than the engine requires. To take care of this excess quantity, I provide. a by-pass passageway communicating with the inlet side of the pumping means for by-passing or returning the excess fuel to the inlet side of the pumping means. Such bypass passageway is closed by the valve mechanism when the pumping means is inactive, but is opened thereby as soon as the pumping means is actuated.

Reference will now be made to the drawings for a more detailed description of the invention. In the drawings:

Fig. 1 is a cut out isometric view, illustrating one form of pump. I

Fig. 2 is a horizontal sectional view taken in a plane indicated by line 2-2 in Fig. 1; the right angle line l--l in Fig. 2 indicating the planes along which portions of the structure are cut out in Fig. 1.

Fig. 3 is a vertical section taken in a plane indicated by line 3-3 in Fig. 2; the line 2-2 in Fig. 3 also indicating the plane of section of Fig. 2.

Fig. 4 is a schematic view of the mechanism in Figs. 1 to 3, in which is illustrated the position of valve mechanism when the pumping means of the pump is inactive.

Fig. 5 is a schematic view similar to Fig. 4, illustrating the position of the valve mechanism when the pumping means is operating.

Fig. 6 is a schematic elevational view of a solid fuel injection system for a compression ignition engine, having the transfer pumping means of my invention incorporated therein.

Fig. 7 is a view, similar to Fig. 3 but on a scale smaller than that of Fig. 3, of another form of Fig. 8. a vertical section taken in a plane indicated by line 8-8 in Fig. 7.

Fig. 9 is a schematic view, showing the position of valve mechanism employed in the pump of Figs. '7 and 8 when the pumping means is inac- Fig. 10 is a schematic view similar to Fig. 9, illustrating another position of the valve mechanism when the pump is operating.

With reference to Figs. 1, 2 and 3, the pump l of my invention comprises a casing composed of an upper casing section 2 and a lower casing section 3 having accurately machined faces which are secured together by suitable cap screws 4. The casing sections are formed withsuitable apertures and passages to provide a passageway for feeding fluid from an inlet to an outlet and in which pumping means is located; a by-pass passageway for returning fluid to the inlet side of the pumping means; and a priming passageway for providing a path for the flow of fluid past the pumping means. Such passages will now be described.

Lower casing section 3 has drilled passage 6 which has threaded connection means 8 at one end thereof adapted for connection with a suitable source of fluid supply such as a tank. A cross-passage 9 communicates with passage 6, and with aperture H open at the top face of casing section 3; such passage 9 being formed by drilling through an edge of section 3, and being subsequently closed by means of plug l2. A pair of apertures l3 and M are formed through the top face of section 3 .to communicate with passage 6.

Upper casing section 2 is formed with counterbored pump chamber l6 having rotary intermeshing pump gears 11 therein, one of which is fixedly secured to shaft l8 journalled in neck l3 of such casing section. Bevel pinion 2| on shaft 5 I8 is adaptedto engage suitable driving means to actuate the pump gears. The top of neck I9 is formed with a flange 22 to which is secured plate 22 having a machined face for securing of the pump. Aperture II in section 3 communi- 1 cates with pumping chamber H5 at the inlet side of the pump gears when casing sections 2 and 3 are assembled together.

The outlet side of chamber l6 communicates with passage 23 in which is slidably mounted 1 plunger valve member 24. Passage 23 is formed by drilling through an edge of section 2, and contains resilient yieldable means in the form of spring 26 which applies pressure to urge or thrust valve member 24 toward a stop formed by conical 2 shoulder 21 against which a. conical edge on the end of plunger 24 is adapted to abut. A plug 28 having a hollow stem 29 for centering spring 26, serves to provide an abutment for the spring and to seal the otherwise open end of passage 23. 25

sage 23 are another pair of apertures 33 and 34 30 which also communicate with passage 36 leading to threaded connection 31 adapted for attachment to an outlet conduit for the pump; the apertures 33' and 34', shown in Fig. 1, being merely for the purpose of facilitating formation of apertures 33 and 34 by drilling through the underside of section 2. Such apertures 33' and 34' do not perform any function in the conducting of fluid and may, therefore, be considered sealed.

When the pumping means I1 is inactive, it is apparent that fluid can flow by gravity through inlet connection 8, passage 6, the passage formed by apertures l4 and 32, across passage 23, through aperture 34, passage 33, and out through outlet connection 31; the plunger valve 24 being held by spring 26 in a position to close apertures 33 and 3|, but to leave aperture 34 uncovered or open. Thus, when the pumping means I! is inactive, the described apertures and passages provide a normally open priming passageway extending past or shunting such pumping means to allow flow of fluid by gravity. Fig. 4 may be referred to for illustrating the priming passage- The described priming passageway is connected to both the inlet and the outlet side of the pumping means because it communicates with passage 9 and aperture I l and with outlet connection 31. It is, hence, apparent that such priming passageway must be shut off upon operation of pumping means l1. Otherwise, the priming passageway would provide a return to the inlet side of the pumping means and no pumping would obtain.

To enable pumping of fluid when pumping means I1 is actuated, plunger member 24 is 6 automatically shiftable upon application of fluid pressure thereto created by the pumping means, to close aperture 34, and thus close the priming passageway; aperture 32 also being closed. At

the same time, aperture 33 is uncovered or opened,

aperture 33 and passage 36 provide a feed pas- 75 sageway in which pumping means I! is located; such feed passageway being normally closed when the pumping means is inactive.

The pump is so designed as to supply a quantity of fluid in excess of that normally required by the means connected to outlet connection 31, to insure such means/being supplied with an ample quantity of fluid under all circumstances. To take care of this excess quantity, the spring 28 is chosen of such strength as to permit plunger member 24 to uncover also the passage formed by apertures l3 and 3| upon actuation of the pump. Such passage, in cooperation with passage 6, passage 9 and aperture thus provides a by-pass passage back to the inlet side of the pumping means, as is indicated in Fig. 5; thebypass being opened or uncovered after the priming passageway is closed. In this connection, it will be observed that spring pressed plunger member 24 serves to maintain a minimum substantially constant pressure to insure that the fluid is supplied by the pumping means I! under adequate pressure. In practice, the passage 23 is chosen of such size and the spring 26 of such strength, as to maintain a minimum pressure of about 15 pounds per square inch when the pump is connected as a fuel transfer pump in a solid fuel injection system for a compressionignition engine.

Reference is made to Fig. 6 which illustrates the installation of the pump, to serve as fuel transfer means in a solid fuel injection system for a compression ignition engine 38, or the like. On such engine 38, is mounted a fuel injection pump casing 39 containing a plurality of high pressure fuel injection pumps 4| of suitable construction, and which are connected by conduits 42 to fuel pressure actuated fuel injection nozzles 43. Fuel injection pumps 4| are actuated from rotatable cam shaft 44 in pump casing 39 and which is driven from the engine.

Transfer pump is secured to pump casing 39 by cap screws 46 passing through the machined flange 22 and plate 22' on pump neck I9; the bevel pinion 2| on pump shaft |8 being driven by bevel gear 41 secured to cam shaft 44. The inlet connection 8 of the pump is connected by conduit 48 with the fuel source or tank 49 from which the now of fuel is controlled by hand operated valve 5|-which is usually left open except when parts of the fuel injection system are disconnected. Outlet 31 of the pump is connected through conduit 52 to oil filter casing 53 secured to pump casing 39. A suitable manifold connection 54 is provided between fuel filter 53 and fuel injection pumps 4|.

In operation of the fuel transfer pump I in the fuel injection system, it will be noted that when the pumping means I! is inactive, the priming passage including aperture 34 will be open to allow priming of the fuel system by gravity flow from the fuel source or tank 49. Upon actuation of the pumping means |l, sufficient pressure will be imparted to the fuel to shift automatically plunger member 24 to the right, in Fig. 1, and thereby automatically close aperture 34 of the priming passageway. At the same time, fuel will be supplied under pressure through the feed passage, to the fuel injection means including fuel injection pumps 4|. Also, the by-pass passageway, including apertures 3| and 3, will be uncovered by plunger member 24 to allow by-passing of the excess quantity of fuel. In this connection, it is to be observed that aperture 33 of the feed passageway is ahead of aperture 3| of the by-pass passageway. Thus, when plunger member 24.is automatically shifted by the fuel pressure created by the pumping means |'I, aperture 33 will be uncovered or opened first to insure ample pressure being built up rapidly. Under normal operating conditions oi the engine, both the feed passageway and the by-pass passageway are always uncovered or open. However, should the engine be rapidly accelerated so as to place on the fuel injection system an extraordinary demand for fuel, the pressure will tend to fall off. This allows plunger member 24 to shift to the left, in Fig. 5, and close momentarily the by-pass aperture 3|, thus cutting on the bypass passageway and insuring that the engine has an adequate supply of fuel under this abnormal operating condition. Upon normal operation of the engine, the plunger member 24 will assume the position shown in Fig. 5.

Figs. 7 and 8 illustrate another form of fuel transfer pump which is easier to make than that of Fig. 1. Also, in the pump of Figs. 7 and 8, a plunger member or valve of special construction is employed for controlling the ports. The passages and apertures of the modification of Figs. '7 and 8 are of the same arrangement as that in the Fig. 1 modification and the pump of Figs. 7 and 8 functions substantially the same as that of Fig. 1. Hence, the same reference characters are applied to designate such passages and apertures. Instead of being made up of two casing sections, the pump of Figs. 7 and 8 is formed of three casing sections, the intermediate one 6| being provided as a separate member for containing the plunger mechanism. As can be seen more clearly from Fig. 8, the thickness of intermediate section 6| determines the capacity of pumping chamber l6 which is formed between the flat machined faces of the upper and lower casing sections; the proper thickness of pumping gears I1 being chosen in accordance with the thickness of section 6|. Because chamber l6 for the gears I1 is formed by the spacing between the upper and lower sections, counterboring of chamber l6 as in Fig. 1 modification is obviated. Such counterboring offers manufacturing difliculties because the counterbored face at the ends of the gears must be machinedaccurately and this is difficult to do. At the same time, the Fig. 7 construction provides a ready arrangement for making pumps of varying capacity, by merely employing intermediate sections 6| of varying thickness and choosing the width of gears ll accordingly.

Plunger member 62 is formed with a socket 63 at its rear end to receive spring 64 to aid in centering the spring. Intermediate its ends, plunger member 62 is formed with an annular groove 66 communicating with cross-passage 61 in turn communicating with aperture 68 leading to the left end of plunger member 62. Such end of the plunger member 62, when the pump is inactive, is spring pressed against a wall of pump chamber l6, and is of reduced diameter to pro vide shoulder 69 against which fluid pressure can act to shift the plunger member. When the pumping means is inactive, the right-hand por-- tion of plunger member 62 closes both the feed passageway aperture 33 and the by-pass passageway aperture 3| but leaves the priming pas sageway open as indicated in Fig. 9.

Upon shifting of the plunger member inwardly caused by pressure of fluid against shoulder 69, upon actuation of the pumping means, fluid flows under pressure through the passageways 68 and 6'1 into annular groove 66 to act also against shoulder II. When this occurs, the feed and priming passageways are uncovered and fluid can flow therethrough from groove 66, and the priming passageway is closed, as indicated in Fig. 10.

from said inlet to said outlet, a primingpassageway communicating with said feed passageway at both the inlet and the outlet side of said pumping means and normally open when said pumping means is inactive to provide a path for flow of fluid past said pumping means, a by-pass OSCAR L. STARR.

CERTIFICATE OF CORRECTION.

Patent No 2,115,555.

OSCAR L. STARR.

5 Because the pressure is applied against both passageway communicating with the inletside 5 shoulders 69 and II, it will be apparent that the of said pumping means and adapted to commuplunger is balanced at two spaced points, the nicate with the outlet side thereof, and a spring plunger having cylindrical bearings at the porpressed member at the outlet side of said pumptions 12 and 13 at each end of annular groove ing means substantially closing said feed and I 1 66. Thus, unequal wear on the valve member is said by-pass passageways when the pumping w prevented, which tends to occur in the arrangemeans is inactive but shiftable by pressure of ment of Fig. 1 where the pressure is only applied fluid upon actuation of said pumping means to against one end of the plunger. Also vibration uncover said feed and said by-pass passageways and sticking of the plunger is minimized. The and to close said priming passageway.

15 same type of plunger can be used in the first de- A pump having a feed passageway includscribed modification if so desired. ing an inlet for fluid and an outlet for fluid, 0

From the preceding description, it is seen that pumping means in said passageway for feeding both forms of the fuel transfer pump of my fluid from said inlet to said outlet, a priming invention contain, in a single casing of simple passageway communicating with said feed pas- 0 construction, apriming passageway which is norsageway at both the inlet and the outlet side mally open when the pumping means is inactive, of said pumping means and normally open when to allow automatic priming by flow of gravity said pumping means'is inactive to provide a path from the tank 49. At the same time, as soon as for flow of fluid past said pumping means, a byoperation of the pumping means is initiated, such pass passageway communicating with the inlet priming passageway is automatically closed to side of said pumping means and adapted to comallow the feeding of fuel under pressure to the municate with the outlet side thereof, and a 0 fuel injection means. Also a by-pass passageway spring pressed member at the outlet side of said is automatically opened for by-passing the expumping means substantially closing said feed cess fuel back to the inlet side of the pump. and said by-pass passageways when the pump- When the pumping means becomes inactive, the ing means is inactive but shiftable by pressure n priming passageway is automatically opened of fluid upon actuation of said pumping means again, to allow the gravity flow without maniputo uncover said feed and said by-pass passagelation of any other valves or mechanism. ways and to close said priming passageway, said I, therefore, claim as my invention: by-pass passageway being so arranged with re- 1. A pump having a feed passageway, pumping spect to said feed passageway as to be opened means in said passageway, a priming passageway subsequent to the opening of said feed passage- 0 communicating with the inlet side of said pumpway upon shifting of said member. ing means and normally open to the feed pas- 4.,A pump having a feed passageway and sageway when said pumping means is inactive pumping means in said passageway, a priming to provide a path for flow of fluid past said pumppassageway communicating with the inlet side of ing means, a by-pass passageway adapted to consaid pumping means and normally open, when 40 vey fluid around said pumping means, and said pumping means is inactive, to provide a path mechanism substantially closing said by-pass for flow of fluid past said pumping means, a bypassageway when the pumping means is inactive pass passageway adapted to convey fluid around and operable by pressure of fluid upon actuation said pumping means, and mechanism substanof said pumping means to uncover said bly-pass tially block ng Sa d Y-D -S p way when passageway and close said priming passageway. the pumping means is inactive and operable dur- 2. A pump having a feed passageway including ing actuation of said pumping means to unblock an inlet for fluid and an outlet for fluid, pum said by-pass passageway and substantially block ing means in said passageway for feeding fluid said priming passageway.

. It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first I column, line 33, before the word "times" insert all; and that the-said Letters Patent should be read with this correction therein that the samemay conform to the recorder thecase in the Patent Office.

si ned and sealed this 18th day of April, A.-n.- 1959.

Henry Van Are-dale (Seal) Acting Commissioner of Patents.

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