US2233709A - Fuel supply unit for oil burners - Google Patents

Description

March 4, 1941- H. c, OSBORNE FUEL SUPPLY UNIT FCR OIL BURNERS Filed Jan. 2, 1937 4 Sheets-Sheet 1 6? 08m 33 [Ma-4....

and flt-w i 54% ys- March 4, 1941. H. c. OSBORNE FUEL SUPPLY UNIT FOR OIL aumihas Filed Jan. 2, 1937 4Sheets-Sheet 2 80 Herb/er? C: 0550-7038 March 4, 1941. H. c. OSBORNE ,FUEL SUPPLY UNIT FOR 011. .BURNERS Filed Jan. 2, 1937 4 sheets-snug s March 1941- v H. c. OSBORNE 3,709 I FUEL SUPPLY UNIT FOR 011.. summns f Filed Jan. 2, 19s! 4-Sheets-Sheet 4 v All.

Patented Mar. l,

2,233,109 rum. SUPPLY Um'r roa on. BURNERS Herbert C. Osborne, Racine, Wis, assignor, by

inesne assignments, to Webster Electric Conipany, Racine, Wis., a corporation of Delaware Application January 2, 1937, Serial No. 118,794

1 Claim.

The present invention relates to fuel units for oil burners, and is particularly concerned with fuelunits of the type which preferably include a liquid fuel pump, a strainer, and a pressure regulator unit..

One of the objects of the invention is the provision of an improved fuel unitof the class described, the mechanism of which is so arranged that with but few slight changes in construction and/or assembly the units may be arranged to meet all of the four requirements of the manufacturers of oil burners who use such units.

Assuming that the unit includes a pressure regulator, a strainer, and a pump, the burner might be located on the right hand side and the pressure regulator on the left hand side, or vice versa.

In each of these arrangements it might be required that the pump be arranged for right hand rotation or for left hand rotation. Therefore, the four possible requirements of customers with respect to the arrangement of the parts of the unit are that they may require right hand rotation, or left hand rotation, with either the strainer on the right or the strainer on the left.

Another object of the invention is the provision of an improved fuel unit for oil burners which may be embodied in a single stage pumping device or a double stage pumping device, and which may be utilized with a single pipe system or a return pipe system with reference to the excess of liquid fuel that is discharged by the pump.

Another object is the provision of an improved strainer unit, the parts of which are readily removable as soon as the cover, has been removed so that they may be inspected, repaired, or replaced with a minimum amount of difliculty.

Another object is the provision of an improved pressure regulator unit which has its parts so arranged that they may be very quickly removed from the housing as soon as the cover is removed, thereby facilitating the inspection or repair, and reducing the amount of machine work involving fastening devices, to a minimum.

Another object is the provision of an improved pump unit having'p'rovision for preventing seal leakage around the shaft of the pump without interposing more than a minimum amount of friction to the rotation of the shaft, and having means for indicating a fuel leak through the seal, as distinguished from leakage of lubricating oil along theshaft.

Another object of the invention is the provision of an improved pump unit which is adapted to be taken apart with a minimum amount of labor,

the shaft being capable of immediate removal after its bearing plughas been removed for inspection or repair.

Another object of the invention is the provision of an improved fuel supply unit for oil burners, having a fuel pump, a strainer, and a pressure regulator. in which the parts of the pressure regulator and parts of the strainer are interchangeably adapted to be used in either of the housings provided with the pump.

Another object of the invention is theprovision of an improved fuel unit for oil burners, in

which all the connections for an installation are located at the bottom, for greater convenience.

Another object of the invention is the provision of an improved fuel unit for oil burners, which is providedwith an oil reservoir surrounding the gear pump, and with means for restricting the intake passage of the. pump, both for the purpose of silencing the noise involved in the operation of the gear pump. The restriction on the intake passage of the gear pump tends to volatilize the lighter parts of theliquid fuel, which cushions the action of the gear teeth and reduces noise.

Another object of the invention is the provision of an improved pumpstructure, the parts of the pump being built up of a series of separate steel plates by means of which these parts may be more accurately machined and produced in large volume, at a lower cost, and constructed in such manner that the pump is adapted to operate for longer periods of time without likelihood of leakage, or change of dimensions due to wear, and by means of which the pump may bearranged either for right hand or left hand rotation, or for use with the strainer on the left hand or the right hand,

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the four sheets of drawings,

Fig. 1 is a front elevational view of a two stage fuel supply unit constructed according to the present invention, the front side being that opposite to the projecting drive shaft;

Fig. 2 is a vertical sectional view, taken on the plane of the line 2-2 of Fig. 3,'looking in the 'direction of the arrows, showing thedetails of the two stage pump unit on the plane of the line 3-3 of Fig. 1, looking in the direction of the arrows, showing the details of construction of the pump and its shaft sealing device. This view 11- lustrates the arrangement of the parts of the pump when it is arranged for right hand rotation with the strainer on the'left and the valve on the right hand side. The gear arrangement is the same for left hand rotation when the valve is placed on the left and the strainer is located on the right hand side.

Fig. 4 is a fragmentary, vertical sectional view, taken on the plane of the line 44 of Fig. 3, showing details of construction of the .pump mechanism, and in particular the bearing plate;

Fig. 5 is a fragmentary sectional view, taken on the plane of the line 5-5 of Fig. 3, looking in the direction of the arrows, showing the opposite sideof the pump bearing plate and other details;

Fig. 6 is a vertical, sectional view, taken on the plane of the line 6-6 of Fig. 3, showing the fuel unit casting, which may be interchangeably used to provide a pump for right hand rotation or left hand rotation, the figure particularly showing the part of the housing to which the pump mechanism is attached;

Fig. 7 is a fragmentary sectional view, taken on the plane of the line 'I-l of Fig. 6, looking inthe direction of the arrows, showing the silencer plug for restricting the intake passage of the pump to reduce noise in the operation of the pump;

Fig. 8 is a vertical sectional view, similar to Fig. 3, but showing the position of the parts of the pump mechanism when the pump is arranged for left hand rotation with the strainer on the left and the valve on the right, or for right hand rotation with the valve on the left and the strainer on the right;

Fig. 9 is a vertical sectional view, taken on the plane'of the line 9-9 of Fig. 8, looking in the direction of the arrows, showing the arrangement of the parts of the pump, and in particular an elevational view of the bearing plate in a different position from that of Fig. 4; 1

Fig. 10 is a. vertical sectional view, taken on a plane similar to that of Fig. 3, of a modification embodying the invention in a single stage pump unit, but utilizing the same type of base casting as is used in'the embodiments of Figs. 1-9;

Fig. 11 is a vertical, sectional view, taken on the plane of the line lI-ll of Fig. 10, looking in the direction of the arrows, showing the details of construction of the single stage pump of Fig. 10, and in particular an elevational view of the gear plate;

Fig. 12 is a bottom plan view of a strainer partition plug;

Fig. 13 is a top plan view of the strainer partition plug;

Fig. 14 is a view in perspective of the strainer partition spring;

Fig. 15 is a view in perspective of a valve partition holding spring;

Fig. 16 is a fragmentary, vertical sectional view, taken on the plane of the line l8-I6 of Fig. 3, looking in the direction of the arrows, showing plate I6! in elevation;

Fig. 17 is a fragmentary, vertical sectional view, showing the course of the output conduit from the high pressure gears I83, I84 to the valve chamber I85;

Fig. 18 is a fragmentary, sectional view of a housing for a single stage pump unit, the gears being shown in dotted lines, to show the arrangement of conduits for one form of that unit, adapted for rotation of the drive shaft in a clockwise direction, and having the strainer arranged on the right and the regulator valve on the left, as shown in the figure.

Fig. 19 is a similar view, showing the arrangement of conduits for the same type of unit, when the drive shaft is arranged for counterclockwise rotation, with the strainer on the, right and the regulator valve on the left;

Figs. 20-23 are fragmentary, horizontal sectional views, taken on the planes bearing similar numbers in Figs. 11, 1'7, 18 and 19, looking in the direction of the arrows, showing the arrangement of the conduits, extending from the strainer chambers and pressure regulator valve chambers to the pump gears in each of these modifications.

Referring to Figs. 1 to 3, the present fuel unit for oil burners preferably comprises a fuel pump, indicated in its entirety by the numeral 28 (Fig. 3), a astrainer unit 2|, and a regulator valve unit 22. i

In order to accomplish the objects referred to above, the fuel unit may be provided with a base casting 23 (Fig. 3), to which the pump unit 28 is attached, and which has a pair of housings 24, 25,

the latter'preferably similar in shape, so that the housings may be used interchangeably for housing the strainer unit 2| or the pressure regulator unit 22. In order to make provision for use of the fuel unit with a one pipe system or a two pipe system, the base casting 23 is preferably provided with an internal chamber or conduit 26 adapted to communicate either with the strainer unit or thepressure regulator unit, and also in communication with the pump, as will be described later herein.

The conduit 26 is preferably located between largements 30 at its corners, providing sufllcient body so that when apertures are drilled and tapped for the screw bolts 3 I, the strength of the material will be adequate.

The rectangular open end portions 29 of the housings 24, 25 are provided with the flat ma chined and ground seating surfaces 32, 33, adapted to be engaged by the flat lower face portion 33 of either cover 34, so that the cover has a fluid-tight fit with the housing 24 or 25 when the screws 3|, passing through the cover, are driven home into the housing 24 or 25. A suitable gasket 54' is preferably interposed between the seating surfaces 32 and 33.

The cover 35, used for a housing when it encloses the pressure regulator, is similar in shape, so that either cover 34 or 35 will fit on either housing, but the cover 35 has an inwardly projecting, cylindrical lug 36, formed with a reduced tends over the inner edge of the housing wall 24, providing an annular seat 43, against which the helical spring 44 engages. Each of the housings 24, 25 is provided at its lower end with an enlarged, tapped bore 45 of the same thread and size for receiving a threaded plug. The threaded plug 46, which is used for the housing when it is a strainer housing, comprises a threaded memher having a cylindrical portion threaded complementarily to the bore 45, and having an external, non-circular portion 41.

It is provided with a centrally located bore 48 and counterbore 49, the former being provided with a pipe thread. The opening 48, 49 in plug 46 may be used as the inlet to the fuel unit, being connected with a pipe 58, leading from the liquid fuel in a tank. It may also be used as a clean-out opening by removing the pipe.

When either housing is used for the pressure regulator, it is provided with a cylindrical body 5|, the lower portion of which is similar in shape to the plug 46: that is, it has an enlarged, non-circular formation 41, the bore 48, and the counterbore 49.

The tapped bore 48, however, is then adapted to receive a threaded fitting 52 for connecting a pipe 53, which leads to the burner nozzle, or other device used for a burner.

Each of the housings 24 and 25 is provided with a cylindrical wall, forming a substantially cylindrical chamber 54. but the chamber 54 is separated from an upper bore or chamber 55 by an annular shoulder 56. The bores 54, 55, 56 indicate the parts of the pressure regulator chamber at the right of Fig. 2, and the corresponding similar parts of the strainer chamber at the left will be indicated by the numerals 54a and 55a, for convenience in describing the course of the liquid fuel.

The annular rib 56 is provided with a machined seating surface 51, in each case, and the sizes of the bores 55. 55a are identical, so that the strainer or pressure regulator will fit in either chamber 54. 54a.

The chambers 55, 55a are each provided with an inwardly extending diagonal conduit 58, 59 on the side toward the upper end of conduit 26. The upper end of conduit 26 terminates in a pairof diagonally extending walls 68, 6|, each of which is provided with a threaded bore 62, 63. adapted to be closed by a small screw plug 64 provided with a kerf.

Due to the diagonal arrangement of the walls 68, 6|, the screw plug 64 is accessible through the top openings of the housings 24, 25, and may be removed or inserted at will. The purpose of the plug 64 will be described in detail in the operation of the device.

Referring now to the strainer unit 2| at the left of Fig. 2. this unit is preferably mounted on a partition plug 65. which may comprise a substantially cylindrical member fitting in the machined bore 55a and provided with a lower fiat machined seating surface 66.

The partition plug 65 may comprise a member made of die cast metal, having on its lower surface a plurality of annular, downwardly projecting ribs 61. 68 of substantially rectangular cross section. These ribs are spaced from each other sufficiently to receive between them the strainer members at suitable spacing. and the outermost rib 61 is spaced from the edge of rib 56 in body 24 or 25, to permit a strainer member to be located outside the rib 61.

Each of the ribs 61, 68 is provided with a plurality of apertures or slots 69, 18, passing through the partition g 65 into the chamber 55a. These slots 69 ai n the case of a die cast metal plug 65 are ......w slots at the lower edges of the ribs 61, 68, but may be suitably enlarged at their upper ends, and portions of the ribs 61, 68 may be cut away at the slots 69, 18, as shown in Fig. 12.

The partition plug 65 is also provided with a centrally located threaded bore 1| for receiving the threaded end 12 of a rod 13, which holds the strainer unit 2| together. The upwardly projecting end 12 of the strainer rod 13 serves as a handle for lifting the strainer unit out of its housing 24. The partition plug 65 is held in place against the seating surface 66 by the helical spring 44, which is of greater normal untensioned length than shown in Fig. 2, so that when the cover 34 is secured in place by screw bolts 3|, the spring 44 is placed under pressure, and by engagement with the seating surface 43 on cover 34 it presses and holds the partition plug 65 into the position of Fig. 2. In order to provide the substantially equal spring pressure on all parts of the partition plug 65, the engaging end portions 14, 15 of the spring 44 are flattened out and the end coil is brought into the same plane as shown in Fig. 14. The lower end coil 88 engages about an upwardly projecting cylindrical portion 8| on the partition plug 65.

The strainer unit 2| preferably comprises a plurality of strainer members 16. 11, 18. 19. These strainer members are preferably substantially cylindrical in form and of successively smaller diameter, preferably differing by substantially equal increments of diameter.

The strainer elements 16-19 may be identical in construction except for the difference in size. and each may consist of a tube of fine wire screen formed out of a sheet of screen which is bent to cylindrical form, and its edges overlap and are secured together by solder. Each of the upper and lower borders of the screen elements 16-19 may be suitably reinforced and provided with a solid imperforate portion 82, by dipping the end of each screen element in solder to a depth of about a quarter of an inch, as shown in Fig. 2. Where the screen elements are quite close together and show a tendency to collapse, they may be separated by a spacing member, such as, for example, the spacer 83, which comprises a helical wire spring having its coils located between the strainer elements 11, 18.

Since the depending ribs 61, 68 on the strainer partition plug 65 are of rectangular section, they have cylindrical inner and outer wall surfaces for engaging the reinforced end portions 82 of the strainer elements 16-19. The inner strainer 19 has its upper end fitting against the inner cylindrical wall-of depending rib 68. The next strainer element 18 fits against the outer cylindrical wall of depending rib 68. The coil spring 83 fits loosely between the strainer elements 11, 18. The strainer element 11 fits against the inner cylindrical wall of depending rib 61, and the strainer element 16 embraces the outer cylindrical wall of depending rib 61.

In a similar manner the lower ends of the strainer elements 16-19 (which areall of the same length) fit against the cylindrical surfaces of upwardly extending ribs 84, 85, carried by the end closure 86 of the strainer element 2|.

This end closure plate, as distinguished from the partition plug 65, has through apertures 81, 88 located between the ribs 84, and inside the rib 85, whereas in the partition plug the aperpiston valve member I03.

Cylinder I02 may have a tight frictional firt on tures are located at and through the ribs. The upper edges of the ribs 04, 05 may be tapered for convenient insertion between the screen elements.

Like the partition plug 65, the aperturw 81. 89 in the end plate 86 may be elongated so that fewer apertures are necessary. End plate 85 is also provided with a centrally located bore 89 for passing the threaded end 90 of the strainer rod I3, which has a knurled thumb nut 9|.

When the strainer elements Ii-I9 are assembled between the partition plug 65 and end plate 96, as shown, with the rod I3 passing therethrough and secured at its upper end by being threaded into the bore II, the strainer elements may be clamped in place by means of the nut 9I.

The strainer unit 2I is then inserted in the strainer chamber, which comprises either the housing 24 or 25, and secured in place by means of the cover 34 engaging spring 44. The securement of the cover secures the strainer unit in place, and as soon as the cover is removed for access to the strainer, the strainer unit may be .easily removed by merely lifting it out by means of the handle I2.

Each of the housings 24 or 25 maybe provided with a laterally located boss 92, which has a bore communicating with chamber 54 or 54a, provided with a pipe thread for receiving a pipe 93 or 94. These pipes may be used for connection to a vacuum gauge in the case of the strainer housing 24, or for connection with a pressure gauge in the case of the regulator valve housing 25. Either of the pipes 93, 94 may be replaced with a vent plug where no gauges are used.

The partition plug '65 divides the strainer housing into two chambers, and the liquid must pass through the strainer elements before getting from one chamber to the other, as follows:

Liquid fuel is taken in at the port 49 at the bottom of the strainer unit, and due to the suction of the pump it is drawn in at the apertures 91, 90 of the strainer unit. It also surrounds the strainer unit so that the liquid fuel passes through the strainer elements, as shown by the arrows at the middle of Fig. 2. Thus it passes into the spaces between the strainer elements I9, TI between the strainer elements 18, I9, and thence through apertures 99 and I in the partition plug 65, to the chamber 55a.

' Referring to the right hand portion of Fig. 2, the plug :I may be provided with a cylindrical extension and with a through aperture 95 communicating with an enlarged bore 96. Plug 5I may be constructed of steel and provided with a bronze or brass valve seat plug 91. The valve seat plug 91 comprises a substantially cylindrical member, the lower end of which has a tight frictional fit in the enlarged bore 98 so that the seat plug 91 projects from the bore.

Valve seat plug 91 is provided with a through bore 98, which may be of the same size as the bore 95, and communicates therewith. At its upper end the edge 99 of this bore constitutes a valve seat for engagement with the conical end I00 of a needle valve member IOI. That portion of the valve seat plug 91 which projects out of the plug 5I may be used to support a tubular member I02, which constitutes a cylinder for a the valve seat plug 91 so that it is in fixed position with respect to the plug 5|. Cylinder I02 is provided with a plurality of through apertures I04, preferably located at equally spaced points about its periphery and Just above the valve seat 99, so that the apertures I04 provide communication between the chamber 54 and the space I05 in cylinder E02. 1

The reguiator valve unit 22 is preferably provided with a pressure responsive means comprising a flexible bellows member I09. The bellows I09 may have its upper end initially provided with a substantially cylindrical flange like the flange I0'I at the bottom. This initially cylind-rical flange is passed through an aperture I09 in a cupped partition plate I09, which is of sumcien size to fit in the chamber 55 or 55a. The flange referred to may then be spun over, as at H0, and secured in the cup formation III by a layer of solder, which also provides a liquid- .tight joint between the bellows and partition plate I03.

The partition plate I09 may be engaged by a galvanized steel washer II2, which alsohas a sliding flt in the bore 55, andhas an aperture II3 for passing the bellows spring H4. The coil spring 39, previously referred to, is a very heavy holding spring, such as, for example, a 400 pound spring. As shown, it is rectangular in cross section and comprises a plurality of coils, the upper and lower coils of whichare tapered so that the spring 39 presents flat ends for engagement with the seating surface 38 and with the washer I I2. This assures substantially uniform force applied to the washer H2 and to the bellows plate I09 on all sides. The force exerted by the spring 39 must be sufllcient to resist any pressure which might be placed upon the complete bellows I06 and piston I03 carried thereby, under ordinary operating conditions, so that the partition plate I09 will always be held in fixed position.

The arrangement of the spring 39 and parti-' tion II2 has the additional advantage of provid-' ing an auxiliary relief valve action for emer- V gencies.

Referring to Fig. 2, it will be observed that the partition I09 need only be lifted off its seat high enough to destroy the effect of the seal of the gasket I09a to permit liquid to flow around the partition by pressing the spring 39. A lift of a few thousandths would be sufllcient to destroy the seal and relieve the pressure. In case the piston by-passvalve sticks, excessive pressure in the chamber 54 would force the partition I I2 upward and be relieved through the port 63.

. The spring 39, like the spring 44, is normally slightly longer than the space into which it is compressed in Fig. 2, so that the cover 35 may be applied and the screws 3I started without exerting force on the spring 39; but thereafter, when the screws 3| are driven home, a screw driver must be used, and the spring 39 is placed under a heavy pressure, referred to above.

Like the strainer unit 2|, the regulator valve unit 22 maybe quickly taken apart by merely removing the cover 35, which releases the spring 39 and all other parts, so that the bellows I06 and piston I03 may be removed for inspection.

No other securing devices are needed, and therefore the machining of parts incident securing devices is eliminated.

The lower end of the bellows I06 has its cylinto other drical flange III'I engaged about the'cylindrical surface of a radially projecting flange II5 carried by a supporting plug H0. The supporting plug 0 may be constructed of brass, and it has an upwardly projecting annular flange III sura socket forrounding a bore III, which provides the lower end of bellows spring I I4.

through the piston I03 and into the plug II6 after these parts are fastened together. An axially extending bore I2I in the plug 6 cornmunicates with the by-pass port I20. The upper, inner corner I22 of the cylinder I02 provides the cut-oi! edge of the piston and cylinder valve.

In order to provide the piston I03 with a dellnite cut-oft edge, the piston I03 is provided with .a flattened portion I23 extending across the end of the aperture I20,,and the flat shoulders at the end of this flat portion I23 have corners, the upper one of which constitutes a cut-off edge for the cylinder and piston valve.

It willzbe seen that the chamber 54 communicates with the chamber 55 through the aperture I20, aperture I2I, bellows I06, and aperture H3, and this communication may be cut off by the cut-off corner I22 on cylinder I02 cooperating with the piston I03.

The piston I03 is also preferably provided with a leakage slot I24 which extends from the recess provided bythe flattened portion I23 down to the lower end of the piston, parallel to the axis of the piston. This leakage slot is adapted to provide leakage from the chamber 54, by means of apertures I04, space I05 leading to slot I24, and thence to aperture I20, whenever the piston is in the position of Fig. 2, with the needle valve leading to the burner port 49 closed. when the regulator valve is closed, the pressure in the chamber 54 is relieved through the leakage port I24 leading to the chamber 55, and eventually back either to the inlet of the pump or to the by-pass port 21.

The amount of leakage permitted by the slot I24 is not suflicient, however, to effect the operation of the bellows I06, which moves responsively to the pressure in the chamber 54. The cylinder I63 has its bore ll9extending beyond the plug "6 and communicating with a smaller bore I25 centrally located in the lower end of the piston.

Between the bores H9 and I25 there is a partially spherical surface I26 adapted to engage the ball I21, which is carried by the upper end of the stem of needle valve IN. The stem proiects through the aperture I25, with which it has a suitable clearance, and the upper end of the ball I21 engages the end I26 of plug II6, there being suiflcient clearance about the ball I21 to provide a limited universal movement.

Thus the conical end I of the needle valve IN is adapted to find its own proper position with respect to the circular seat 99, thereby assuring a perfect closure of the needle valve at all times. The piston I03 is acted upon by the spring II4, which engages in the socket II8 of plug H6 at its lower end. The upper end of the spring H4 is engaged in a cup shaped member I 26, which has its depending flange embracing the spring, and has a partially spherical depression I29 for engaging the complementary end of screw 4|. The cup shaped member I26 may have its depending flange slotted so that even though it is screwed down into engagement with the washer II 2, the liquid fuel has egress from the bellows I 06, through the slots of the cup.

The operation of the pressure regulator is as follows: Liquid fuel under pressure is supplied to the chamber 54 when the pump is started and when the pressure of liquid fuel arrives at a predetermined pressure suitable for operation of the burner, this pressure acting on the bellows I06 and piston I03, to which it has access, from the chamber 54, moves the piston and lower end of the bellows upward in Fig. 2, carrying with it the needle valve IOI. The needle valve IOI then opens the burner port at the seat 99, and liquid fuel is supplied to the burner. As the pressure continues to rise in the chamber 54, for the reason that the pump is adapted to supply an excess of fuel over that required for the burner, the piston I03 movesup until the cut-off edge I22 places the aperture I in communication with the chamber 54.

An amount of liquid fuel is by-passed through the apertures I22, ',I2I and bellows I05, back to the chamber ,55, to the by-pass port 21 or to the inlet of the pump, depending upon the opening of the piston valve at I22.

The piston valve continues to open a sufllcient amount to.by-pass this excess oil and thereby maintains the pressure substantially constant in the chamber 54 within predetermined limits. The leakage that occurs through the leakage slot I24. during this time does not materially affect the operation of the valve,- but when the pump is shut down and ceases to generate pressure, the pressure drops in the, chamber 54, the bellows I06 elongates, moving the piston I03 downward, and closing the by-pass port I20. Thereafter the needle valve IOI closes the burner port at seat 99. and the continuing leakage through the slot I24 reduces the pressure in the chamber 54- tov atmospheric, permitting a more positive seating of the needle valve IOI, since there is no longer any pressure exerted on the bellows I06 except that of the spring I I4.

The pressure at which the needle valve will open may be suitably adjusted by the pressure on the spring II4, which is adjusted by means of the screw H. The spring ,II4, like the springs 44 and 39, has the endmost coil at its upper end disposed in the same plane. The same is true at the lower end, so that the spring exerts a substantially axial force on the piston I03 and does not tend to bind the piston in its cylinder I02, as might be the case if the spring engaged only at one side.

The base casting-23 (Fig; 3) is provided (Fig. 6) with a machined face I3I of sufllcient size to support the pump mechanism and the reservoir housing I32, which is adapted to enclose the pump and to permit it to be enveloped by a supply of liquid fuel.

The reservoir housing I32 comprises a cast metal member of oval cup shape, having one open end and having its closed end provided with a face I33, which may be used for the name plate I34, which is secured thereto by headed pins I35, driven into apertures.

The outer wall I36 of the reservoir housing I32 is suitably thickened at a plurality of equally spaced points to provide sufllcient material so that apertures may be bored in the wall I36 of the housing for the screw bolts I31 without communicating with the reservoir space I38.

The screw bolts I31 pass through the apertures in the reservoir housing I32 and through a suitable gasket I39, and are threaded into threaded bores located in the face m 6: the

(main casting '23. The edge, I40 of'the housing wall I36 is machined to provide a fluid-tight engagement with the face I3I when the screw bolts I31 are driven home, clamping the gasket Referring to Figs. 6 and Leach of the'upper chambers 66 and 66a isin communication with j a port I 4I, I42, respectively, each port being'located in the faceI3I of the main casting 23. The

port "I communicates with the bore I43, which leads to a cored and milled recess I44, located in the side of upper strainer chamber 55a.

The port I42 communicates by means of aperture I45 with a similar recess I46 located inthe upper pressure regulator chamber. 65. 'Each of the bores I43, I45 isprovided with a threaded portion I41 at itsupper end for receiving" a threaded restriction sleeve or plug I48, having a kerf I49 for receiving a screw driver.

This restriction plug is placed in the conduit 'I43 'leading [from the strainer chamber, but since both the bores I43, I45 are ofthe same size,

the plug will fit either conduit, and the strainer shaft. It always is" on the side of the bearing toward the idler shaft, because in this position the liquid pressure forces the gears, and hence the shafts, apart, thus leaving space between the shaft and the bore I52 for the entrance of pumpage which servesas the lubricant.

The bore I52 serves as a bearing for the pump shaft I56. The wall I5I is provided with a pair of additional bores I51 and I58, each of which is adapted to recelvea pin I59 or a tube I60.

The bores I51, I58 communicate with the bypass conduit 26, and are to be used interchangeably with the solid pin I59 or sleeve I60, both of which perform the function of lining up and supporting a plurality of steel plates I6I, I62, I63, I64, which form the pump housing. The sleeve I60 performs the additional function of placing the reservoir space I38 in communication with the by-pass conduit 26, and it will be apparent that this communication may be had with the parts arranged as shown in Fig. 3, or with the parts arranged as shown in Fig. 8. Here the same sleeve I60 is again arranged near the top of the plates for the reason that it is desired to keep the reservoir full of liquid fuel up to the sleeve and above the intake ports to the gears of the pressure stage. This makes the pump self-priming.

. The face I3I is also provided with a plurality of threaded bores I65, I66, I61, I68 (Fig. 6) for receiving aplurality of screw bolts I68 which pass through the plates I6I-I64 and are threaded into the bores I65-I68. In the embodiment of Fig. 9, two of these bores I65, I66 are located in the lower part of the face I 3| in position to line up with the same apertures in the plates I 6I-I64, which are arranged in the lowered position.

This slot provides lubricating means for the pump The face I isalso provided with the ports I10, I'll (Fig. 6), which communicate by means of the conduits I12, I13 with thelower chambers 64a and 64 respectively, comprising the lower strainer chamber and lowerpressure regulator chamber; These conduits I12,--'I13' serve as in-" let ports for these chambers, whichever chamber is used as a regulator valve chamber.

In the embodiment oi. Fig.2, the conduit I13 is the effective one, whereas the conduit; I12 is closed.

Plate I6I is provided with apertures "4,116, which are 'adaptedto register with the ports I10, I1I,respectively. 'Plate I6I is also provided with apertures I16, I11, I18, I18, adapted'to cooperate with. slots in the plate I62 to'form conduits under certain conditions. 5 The plate I6I is also formed with the two laterally'intercommunicating gear bores I8I, I82, which are adapted to 'engage the machined edges of the gear teeth of gearsfi64, I55, providingfa close sliding contact. l I n r The gearsl54 and'l65, as well as the high pressure gears I83, I I84, are all'preferably ofthe helical typ for the purpose of reducing noise,

and the direction of helix is so arranged with respect to rotation that helical teeth 'forcethe liquid sidewise towardthe discharge ports of the pump, and are all provided with flat side faces adapted to have a closely fitting sliding contact with the adjacent walls of the plates I6I," I62, I63 or I64. I w 1 The tips I of all of the gearteeth are preferably provided with asurface which appears to be slightly flattened, but which is actually par tially cylindrical and has sliding contact with the peripheries of the gear-receiving bores," such as the bores I8I,' I62. I f

The plate I6I is also provided'withthe apertures I86, I81, located-atthe'top' and-bottom thereof, in Fig. 16, for receiving the sleeve I66 and pin I56. Similar "apertures I66, ,'I81, to which the same numerals have been applied,- are present in-the plates I62 and I63."

Referring to Figs. 3 and 5, the' pumpp'artition plate I62 is of similar shape, and it is; provided with the cylindrical bores I88, I86 for receiving the stub shaft I66 and'the drive shaft I56. These cylindrical bores serve asbearings for those shafts which have a close rotating fit in the bores. v

In addition to these bores, the plate I62 has registering apertures for the-screw bolts. I69, which secure all of these plates together, and to the main casting 23; that is, plates I6I, I62, I63 and I64 have apertures which register witnthe threaded bores I65I68- (Fig. 6) in the main casting 23.

The plate I62 .(Fig. 5) is provided with the apertures I 6|, I82, the former being located to register with the aperture I15 in, plate I6I when the pump is assembled as shown in Figs.- 3 and 5. When the plate I62 is inverted, the lower aperture I62'will appear in the right upper quarter of the plate, referring to Fig. 5, and would register with the aperture I14 in the plate .I'8I for I a diiferent assembly and different use of the unit.

The plate I62 is also provided with the transversely extending rectangularslot I33 which extends from the left side of Fig. 5 to a point 10- cated at the right of the point of engagement of the gears I54, I56. This'is the output can'- duit from the gear pump, comprising the gears I64, I66, leading into the reservoir I38.

Plate I62 is also providedyith a transversely extending rectangular slot I94, which leads from a point slightly spaced from the end of slot I93, that point being located immediately at the right of the point of engagement of the gears, and communicating with the spaces between the teeth at the ends of the teeth;

Slot I94 comprises an intake conduit for the gear pump, consisting of gears I54, I55. This siot communicates with a transversely extending slot portion I at the end, and'located at such a distance from the boundary of the plate that the transversely extending slot I95 will have its upper and lower ends in registry with the aperturcs I11, I19 of plate I6I (Fig. 16).

When the plate I62 of Fig. 5 is inverted so that the slot I95 is at the left (Fig. 5) and the slot I93 at the right, then the upwardly and downwardly extending slot I95 will have its end portions in registry with the apertures I18, I18 of the plate I6I. That condition would be for a reverse rotation of the pump from that which would be necessary for the installation of Fig. 3.

Referring now toFig.5,the inlet for pump gears I54, I55 may be traced as follows: Slot' I94, lower leg of slot I95, aperture I19 (Fig. 16), aperture I4I (Fig. 6), conduit I43, restriction I48, to upper strainer chamber 55a.

The outlet from this stage of the gear pump leads from slot I93 to the edge of the plate assembly into reservoir I38 surrounding the pump. The aperture I11 in the plate I6I and the upper leg of slot I95 are closed because they come againstthe flat face I3I of the main casting 23 at a point where there is no hole in this mode of assembly.

The plate I62 has upon its opposite side, which is shown in Fig. 4, certain additional slots. The apertures I9I and I92 communicate with a vertically extending slot I96 in plate I62 upon the left face thereof (Fig. 3). Vertical slot I96 communicates with a horizontal slot I91 which leads to a point I98 at the right of the point of contact of gears I83, I84 (Fig. 4), which is the output side of the gears.

The next plate I63 of the pump assembly Fig. 3) is similar in shape to the plate I6I, being provided with the apertures I86, I81 for aligning studs I59, I60, and being provided with the bolt hole apertures I65-I68 for the screw bolts I69. This plate is also provided with the gear apertures 200, 21", similar in shape and size to the gear apertures I8I, I82 of Fig. 16. The plate does not have any other apertures, and it serves as a housing for the toothed edges of gears I83, I84.

The cover plate I64 is provided with the same bolt apertures I61--I68 for the screw bolts I69. the heads of the bolts being preferably countersunk in the plate I64. This plate provides a closure for the end of the pump mechanism, but is also provided with an aperture 202 registering with the aperture 203 in the sleeve I60 at the top of Fig. 3 to place the reservoir I38 in communication with the by-pass conduit 26.

Referring now to Fig. 4, the output from the high pressure gears I83, I84 is at the point I98 into theslot I91. The course of the liquid fuel from the high pressure side of the pump may be traced as follows: Conduit I91. slot I96, aperture I9I (Fig. 4), aperture I15 (Fig. 16), aperture I" (Fig. 6), conduit I13, into the pressure regulator chamber 54.

It will be noted in Fig. 3 that the low pressure gears I54 are thicker or wider from face to face than the high pressure gears I83. The low pressure gears I54 are so constructed inorder that they may pump up an excess of fuel over that required for the high pressure stage I83, I84. This excess of fuel is delivered into the reservoir I38, whence the high pressure stage takes its supply through the intake I99. The high pressure stage pumps out of the reservoir I38 as much liquid fuel as it needs, the level being constantly up to the bottom of the conduit 203 in the sleeve I60, and the excess of liquid fuel from reservoir I38 passes over into by-pass conduit 26, whence it may be piped back to the tank in a two pipe system.

In a one pipe system, the excess liquid fuel from reservoir I38 goes into the by-pass conduit '26, the lower end of which is closed by plug 28, and in such a system'the plug 64 is removed and excess fuel passes back into the upper strainer chamber, which leads to the intake conduits I43, I. I95, I94 for the low pressure gears I54, I55.

The high pressure stage of the pump also pumps an excess of fuel over that required for the burner, and this excess is by-passed by means of the pressure regulator valve, through the conduits I20,- I2I, bellows I06, into chamber 55, conduit'63, and by-pass 26. The plates I6I-I64 may be made of cast metal, the apertures and slots therein being cored out, if desired, and later accurately machined, or they may be drilled in later, since they are all round apertures.

The plates are all provided with smooth, machined surfaces, so that when the plates are clamped together they provide fluid-tight engagement between each other. The plate I6I is, of course, slightly thicker than the gears I54, I55, and the plate I63 slightly thicker than the gears I83, I84. The shaft I56 in this embodiment may be of the same size throughout its length, being merely provided with a flattened portion 204 at the end for attachment to the source of motive power. At its inner end, shaft I56 is provided with a transverse slot 205, opening out into the end of the shaft for receiving a key 206.

The key 206 may be a flat plate. having rectangular sides of slightly greater length than the diameter of the shaft I56, with its ends engaged in slots201 formed in the bores of gears I83, I84, and I54.

These slots are similar to that shown in dotted lines in Fig. 11 with respect to a different gear. The same sort of slots are formed in the ends of the stub shaft I90. and keys are provided for securing gears I83 and I54 to rotate with stub shaft I90. The gear I55 is mounted on shaft I56 for freerotation on that shaft. Thus it will be observed that the gears are arranged in a single train, driven from the shaft I56 as follows: Shaft I56 drives gear I84 through the key and slot connection. Gear I84 drives gear I83. Gear I83 drives stub shaft I90, which drives gear I54. Gear I54 drives gear I55. Of course, all of these gears are rotating at the same speed, but by means of such a single train drive all of the backlash is taken up through the gears, thereby reducing noise. Since the shaft I56 is all of the same size and it may be freely drawn from the gear I84 and key 206, it is possible to arrange the fat shaft I56 so that it may very easily be withdrawn to permit'inspection of the shaft seal and other details.

The assembly of the elements of the fuel unit as shown in Fig. 3 is for a pump having right hand rotation, as shown by the arrow, Fig.3, looking at the right or shaft end or rear end of the fuel unit with the valve on the right and the strainer on the left. Certain manufacturers may prefer to have the pump arranged for left hand rotation.

right of Fig. 2, the plates I6I--I64being' so assembled that the apertures therein combine with the' apertures formed in the main casting 23,

with the by-pass and with the burner as previously described. When it is desired to arrange the unit-element Y for a left hand rotation, with the valve on the right, referring to the rear end, or for a right hand rotation,- with the valve on the left, referring to the rear end, then the idler gears I33, I54 must become drivers, and'the gears I04, I55 become idlers and disposed below the drivers, as shown in Fig. 8. This makes the liquid delivery from the teeth toward the holes in the plate I62. The

reason for changing the gears is that the helical teeth' may slope insuch direction as to force the liquid;

The main casting could be provided with such 1 suitable apertures that the manufacturer could make this-assembly in any manner desired, any

unnecessary apertures beingv plugged -up, butthe v in'Figs. 17 and 19, having the circular face 2 preferred. mode of handling the matter is that the manufacturer of the oil burner specify which of the four conditions as to rotation or location of the-.valve are desired. Then, with the same .castings,+the present fuel units can be supplied I this axis or merely lowered to a lower position in in any of the forms desired by merely providing ,suitable conduits. For example, in Fig. 8 the I I shaft 2I5'is located below the driveishaft 2II. By the use of two castings o'f thesetype's, pump iocatio'n 'of the shaft I56 is the samea's in Fig. 3, but theplates I62 to I64 have been swung about the reservoir housing I32. I Plate I6I is always merely lowered (never reversed), so that the hole in the plate and the tube I60-are always atthe top of the plates. The reason for this is that the reservoir overflow should always be higher than pressure pump intake, so that sutflcient liquid will be retained to prime the pressure gears.

The bore I 53' for the alignment of tube I60 is located. above the shaft I56 at the same distance from the shaft as pin I59 is below the shaft in Fig. 3. The bore I5'I for the pin I53 is located below the shaft I56 at the same distance from the shaft I56 as tube I50 is above theshaft I56 in Fig. 3. The plates I6II64 are so arranged that their apertures and, slots provide the conduits previously described to make thepump operate in the same way, except that it may now be arranged for left hand rotation with the valve on the right, or for right hand rotation with the valve on the left.

Referring now to Figs. 10 and 11, these are views which show that some of the same elements may be utilized to provide a single stage "through the same conduits I46, I43, I.

This'can' be accomplished by a reassembly of the parts so that the regulator valve ison the left of Fig. 2 andthe strainer on the In this case the features of the may be identical in construction to the gears I33,

I64, is from the upper strainer chamber 554: The outlet from the pump gears 203, 203 is always on the opposite side of the ge'ars,'. and leads to the regulator valve chamberfl through conduits similarto the conduits III, "3.

g The main casting 2I0 for such a single stage unit (Fig. 10) is similar in construction to that )0! the casting 23 in that ithas the same strainer housing 24, regulator valve housing 25, and bypass conduit 26. The by-Pass conduit 26 communicates with the upper chamber 55a of the strainer housing, as shown in Fig. 2,througii the .same aperture 62 and with thefupper chamber '55 of the regulator valve through the same "threaded aperture '63. Thus, in a single stage pump the pump is again arranged to take liquid from the fuel strainer and to discharge liquid fuel under pressure into the regulator valve housing.

and any excess of fuel which is by-passed by the regulator valve passes back intojthe by-p'ass conduit26 through the port 63. A plug 26'may be removed and a return conduitusedbackto. the

tank or the plug 64 may be removed (Fig. 2)

and'a single pipe system used, by permitting the excess to flow back from the by-pass. conduit 26 through port 62 into the strainer housing 55a.

In each case the drive shaft I56 or 2 may be jfsimilar in construction, and it is rotatably'supported by a cast iron bearing 2I2, which is pressed into e bore 2I3 in the face of the casting. The

single stage castings 2I0 are made in two forms; that is, the form shown in Figs. 11 and 18, having a circular face 2 adjacent the top of one side of the casting. and the other form' shown located on the lower part of the side of'the casting.. V

- In the embodiments of Figs. 17am 19 the idler units may be manufactured meeting all fourrej quirements of oil'burner manufacturerathat is,

pump units may be made with a right handratation of the shaft or a, left hand. rotation, and either of these types maybe made-with the The additional variations in theunits to accomstrainer on the right or the strainer on the left.

plish this result are merely brought about by' drilling the conduits from the'str'ainer tothe pump and from the pumpto theregulator valve,

in a different manner. For example, in Fig. 1i;

the conduit. 2I6 leads from thevv upper part of the strainer housing to the intake side ofthe' gears 206, 209. The conduit 2" leads fromthe" output side of the gears 206, 206 to the iowerpart.

ofthe regulator valve housing.

Each of these two conduits preferably com municates with a diagonal slot 2 I8. 2 I9,arranged in the circular face 2 at the edges of the'teeth' of the gears, on the intake side and output sideof the gears, respectively.

In Fig. 17 the conduit 220 leads from the upper part of the strainer chamber to the input side of the gears, and the conduit 22I leads from the output side of the gears to the regulator valve chamber 54.

It will be observed that the slots 222, 224 in the face 2 are arranged diagonally in order to prevent interference of these slots with the. apertures for the securing bolts 22!. The same is true of the slots in Figs. 11, 18 and 19.

Referring to Fig. 18, 226 indicates the conduit from the strainer to the pump intake, and 226 indicates the conduit from the output of the pump to the pressure regulator valve.

In Fig. 19, 221 indicates the conduit from the strainer to the intake of the pump, and 223 indicates the conduit from the output of the pump to the regulator valve.

Figs. 21, 22 and 23 are horizontal sectional views taken on the plane of these conduits and showing the course of the conduits as described.

Referring now to Fig. 10, the face 2| 4 of each casting is provided with a bearing aperture 229 for receiving and rotatably supporting the end of the idler shaft 2 I5. The face is also provided with apertures 230 and 23I for receiving the alignment pins 232 and 233. A gearhousingplate 234 has suitable apertures registering with the apertures 230 and 23I for receiving the alignment pins 232, 233. It also has the two intersecting gearing bores 235, 236 adapted to support and house the gears 203, 209 as described with respect to the gears in the two stage pump.

The gear housing plate also is provided with suitable apertures 23'! for the securing bolts 225', which are threaded into bores in the face 2I4 of the casting, and which also pass through the cover plate 230.

In the case of the two stage pump or any pump which is surrounded by a reservoir I30, as in Fig. 3, a slight leakage is immaterial, as it will only leak out from between the plates I6I-I64 into the reservoir I38. are necessary between those plates.

In the case of a single stage pump of the type shown in Fig. 10, the plate 234 is preferably formed with suitable grooves 239, 240 for receiving a compressible gasket to effect a water-tight Joint between this plate, the housing casting 2I0, and the plate 238.

The plate 234 is shown in elevation in Fig. 11,

and it will be apparent that the grooves 239- 240 are spaced from but surround the bores 235, 236 which receive the gears 208, 209.

It will thus be observed that the present pump may be embodied in the unit as a two stage or a single stage pump, and in each case the same type of casting may be used with slightly different machinin and slight modification and to make a unit meeting all of the four requirements of oil burner manufacturers.

Referring now to Figs. 3 and 10, the main casting 23 or 2I0 is provided with a tubular extension 2, serving to support the bearing 242 for the shaft I56, and a liquid-tight seal, indicated in its entirety by the numeral 243.

The bearing supporting member 2 is provided with an internal bore 244, the outer end of which is threaded to receive a threaded reservoir body 245, which carries the bearing 242. The reservoir body 245 comprises a cylindrical body having a through bore 246 and having a reservoir 24'! formed therein, and communicating with the bore 246, but closed by the wall of the bearing 242, which has a tight frictional fit in the bore 246.

The bearing 242 may consist of a porous metal bearing adapted to conduct lubricant from the reservoir 241, where it is held by a filling of waste or wicking 248. The reservoir body 245 has an outer, non-circular hub 249. The bore 244 ter minates at an annular shoulder 250, but com- Therefore, no gaskets The seal 243 may be provided with a guide tube 252 adapted to be received in the bore 244, and held therein by engagement with the annular shoulder 250, and with an annular end of the reservoir body 245. The right end of the sleeve 252 is turned down at 253 to form a groove which communicates with an aperture 254 located at the bottom of the sleeve and in registry with a bore 255 through the bearing supporting body 24I.

The purpose of the apertures 254, 255 is to permit any leakage which might leak past the seal 243 to leak directly out of the body 24I and indicate leakage of fuel oil from the seal, as distinguished from leakage along the shaft I56, which might result from the bearing reservoir 241. Thus any fuel leakage is immediately indicated and distinguished from that coming from the self-lubricating bearing.

The member 256 is a tubular shield surrounding the shaft I56 beyond the bellows, and is intended to protect the bellows from the wash of fuel oil; but it may be eliminated. The bellows 251 has one end attached to an annular supporting ring 258, which is clamped between the sleeve 252 and the shoulder 250. Its opposite end is secured on a sliding end wall 259 and has a fluidtight connection with the end wall 259.

End wall 259 comprises a steel member provided with a bore 260 for passing shaft I56, and with a flat annular surface 26I for engaging a complementary surface in the form of a rib 262 on a collar 263. Collar 263 has a tight frictional fit on the shaft I56 and rotates with the shaft. It is spaced from the end of bearing 242 by a hardened and ground steel washer 264, which takes the thrust imposed by the spring 265.

The fluid-tight seal about the shaft I56 takes place at the surfaces 243, 262, which are lapped to provide a fit as nearly perfect as possible; and these surfaces are held in contact by the spring 265, which surrounds the shaft I56, but does not engage the shaft.

Spring 265 engages the bearing 2I2 at one end, the bearing being shorter than its bore by a small amount. This is one way to provide a recess for the spring 265. The other end of the spring fits in a recess in the end wa1l'259, and consequently the end wall 259 of the seal is urged toward the right.

The edge 266 of the end wall has a cylindrical surface, which has a sliding fit inside the sleeve 252, thereby guiding the end wall 259 at its outer edge, and permitting freedom of end wall 259 with respect to shaft I56.

Such a bellows type seal has a minimum amount of friction, yet there is a fluid-tight seal about the rotating shaft which prevents any leakage along the shaft. The shaft has the high pressure gears at its inner and closed end, and next to the high pressure gears are located the low pressure gears, while the chamber to be sealed is actually only in communication with the by-pass conduit 26 so that there is a very-low pressure acting against the seal, comprising merely the amount of head necessary to force the liquid back to the tank.

It will thus be observed that I have invented an improved fuel supply unit for oil burners, which is adapted to fulfill all of the four requirements of oil burner manufacturers. With very little change, the unit can be made for right hand rotation or left hand rotation, with either the strainer on the right or the strainer on the left. It may be embodied in a one pipe system or a two pipe system, by merely making a slight change, and

' may be used in the form of a single stage pump or a two stage pump.

The present arrangement is flexible and adaptable to all conditions with a minimum amount of patterns and castings, and therefore the unit may be constructed at a very low cost, placing it within the reach of a largernumber of manufacturers of oil burners.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claims.

Having thus described my invention. what I claim as new and desire to secure by Letters Patii: ent of the United States, is:

A liquid fuel pump adapted to be assembled differently for rotation in either direction, comprising a metal base member having a plane face for supporting a pump assembly, said member having a shaft bearing, a drive shaft in said bearing, a pair of metal posts mounted in apertures 25 of saidbase member and projecting from said face, a first gear housing plate, a bearing plate, and a second gear housing plate carried by said posts, a cover plate and means for-securing said plates to said base member, a reservoir surrounding all of said plates, said base member having a pair of pump conduitsat each side of said shaft, each of said gear housing plates having communicating cylinder bores for housing two intermeshing gears, and one of said housing plates having apertures forming continuations of said conduits.

said bearing plate having bearings for said drive shaft and a stub shaft, pairs of gears in said bores on said shafts, one pair being larger than the other, said bearing plate having on each side thereof a slot extending from the edge of said bearing plate, to one side of each pair of the meshing gears, and said bearing plate'having on each side artifice branch slogeach three branch slot having one branch extending to the other side of each pair of the meshing gears, and having branches extending into registry with the pump conduits from said base member, whereby said bearing plate may be inverted to adapt the pump for rotation in either direction.

HERBERT C. OSBORNE.

Images