US 1933081 A
Description (OCR text may contain errors)
'Dil-31, 1933. F. STEPHAN 1,933,081
FUEL SUPPLY sx'sTEM Filed May 2o, 1951 4 sheets-sheet 1 .Uf Mfg ,eyo aan. y 419W my.
4 sheets-Sheet s 5 Z 3 0 WU .4567 M w 5MM U b M l V liv Oct. 3l,l 1933. F. STEPHAN FUEL SUPPLY SYSTEM Filed May 20, 1951 O Ct- 31; 1933. F. STEPHAN FUEL SUPPLY SYSTEM Filed May 20, 1951 4 Sheets-.Sheet 4- It may be attached in substitution of the carof the arrows.
buretor and thevmounting is made simple and 'efficient since it is only necessary toinsert three bolts or the like through the tubular Pscrews which hold the housing 27 and the .main frame 1 in assembly. 'I'he top shell 23 can be turned around to adjust the fuel inlet 24 to any position radially to the device. 4The attachment of the fuel line' 24 can therefore be accomplished with ease since the device lends itself readily -to any -engine construction. f
I shall now describe the interior assembly of parts with reference to the Figure 3. This iigure is an enlarged cross-section taken along the lines 3-3 in Figure 2 looking in the direction ence numerals to identical parts in order to facilitate the description.
Referring now to Figure 3, it will be seen that themain frame member 1 has a central portion which is joined in its lower part by the integral iiange portion 2. Projecting from flange portion 2 are threevlateral extensions each provided with a threaded hole.v One ofl these ex,-`
- tensions is shown in `Figure 3 and designated by the numeral 3. It corresponds to the extension. 3 shown in Figure 1. In the flange portion 2 are as many openings as there are pump cylinders. The cylinders, such as the vcylinders v6 and 9, are each provided with a shoulder such as 32, 33, respectively, and these` shoulders engage correspondinglyV recessed or turned down portions on the slightly sloping surface 34, 35l of the flange V2. It will'be seen that .the material oi the flange 2 is sloping downl laterally-from the central portion l as indicated by the dottedlines 34-35. The same is the case in the upper part of the vframe, asv is. indicated 'by the reference numerals 66-66. These lsloping surfaces give strength.to the main frame which may be a suitable casting or made in a drawing process.' Bronze, aluminum or other material may be used for the'frame. The` circular recesses in the sloping surface 34-35 provide proper seats for the` `shoulders (32, 33)"'on the pump'"cylinders.` The `cylinders project with their lower portions through the vopeningsirrthe .flange 2in1-'the frame 1 asis indicated'by the numerals 36, 37. The lowest portion of each'cylinder-.is further The frame 1 carries a laterally extending flange `'4.0 integral 4with the frame and axially spaced are provided in 'the flange 40 for the reception of auxiliary pistons suchas the .pistons 42, 43 shown inthe drawings. The auxiliary piston 42 co.
operates with the-main piston 44 contained within the pump cylinder 6, andthe auxiliary piston 43 cooperates with the main piston 45 contained within the .pump cylinder 9.. ...I are as many auxiliary pistons 42, 43., as there are pistons i 44-.45, reciprocating within tnejrm'mp cylinders such 8S. 6 .and 49..'
The lower portionof'eachof lthe main (44,45) is formed lintoa headsuchI as`.indicat.ed by thereference' numerals 46 and 4 7f,.respeotively.
The headbf each piston is provided with"V a -set oishoulder as shown in the drawings, the diameter of which corresponds substantiallyv to the diameter of the lower portion of the cylinders designated inthe drawings bythe numerals 38,
I have applied the same refer-- 48 is disposed between the head 46 of the piston` 44 and the shoulder :36 of the cylinder` 6 .and tends to pull the main piston 44 downwardly in the direction of the cooperating auxiliary piston` 4 2; the spring 49 is disposed between the shoulder portion 37 lof the pump cylinder 9 and the head 47 of the main piston 45, and gives the piston 45 a downward tendency in the direction of the cooperating auxiliary piston 43.
The same arrangement is duplicated with each of the other pump pistons andthe corresponding cylinders. It is understoodof course that there are as many pump cylinders and pistons as there are engine cylinders since each of the pump pistons and cylinders is intended to meter and measure the fuel for va specific one of the engine cylinders.
Each of the auxiliary pistons v(42--43) is disposed in acorresponding one of the circularly arranged holes in the flange portion 40 of the main frame. It is of a cylindrical form and provided with a central boring for receiving a spring such asvthe springs 50 and 51. Each cooperating main piston has a counter drilled hole, and the spring extends with one end into this hole as shown, and into the central boring in the auxiliary piston. The spring exerts thus a tendency on the 'corresponding auxiliary plston to-separate the same from the main piston.` For example, it will be 53. Suitable lubricating grooves are provided on each of the cylindrical auxiliary pistons in order to,provide for a good lubrication. The operation of the auxiliary pistons relative to the main pistons will be described later on after several other structural details are explained..
'boring 54. is provided centrally within the lower portion of the main frame 1. This boring turned down as is indicated by the mlmM1554 serves as a journal or bearing for the bearing portion 55 of a rotary cam 58. This bearing portion 55 is provided with lubricating grooves such as 56 and 57, and with a transverse lubricating extending laterally' therefrom in disc form is the cam plate -58 having the dwell 59. @The lower .lplined portion 60 is also integral with the cam 58 and with the journal portion 55 thereof.
4'I'he splined portion 60 is disposed within an internally splined gear 28 journaled in lthe lower porion of the housing 27 my means of the bearing 61. This bearing is held within the bottom portion of the housing 27 by means of the nut 62 and by means of the closing member 63. The nut 62 engages the threaded end of the internally splined bushing of the gear 28 while the member 63 is threaded` into the internally threaded housing`27 'as shown. yThe bearing 61 is thusheld in engagement with the housing by the member 63, while the driving member or gear 28 is held in position by means of the nut 62. The splined portion 60 of the rotary cam is disposed within the internally splined gear 23 and is therefore axially movable therein and rotatabletherewith. In
hole 58'. Integral with the bearing portion and A other words, the cam will rotate with the gear but can be shifted axially to the gear.
Laterally extending projections, such as 64, on the housing 27, regist'erwith the corresponding projections (3) on the main frame. There are three such laterally extending projections which register with each other. The housing 27 is held in engagement with the main frame 1 by means of tubular screws such as the screw 65, one for each pair of registering lateral extensions on the housing 27 and on the main frame 1, respectively. If it is desired to gain entrance into the interior of the lower portion of the device, it is therefore merely necessary to remove the tubular screws and to withdraw the housing 27 from engagement with the main frame. The rotary cam, the auxiliary pistons and the lower portion of the main pistons will thus be exposed for inspection.
The porlion of the housing 27 within which the` rotary cam operates will normally be lled with lubricating oil or grease. The device is intended to pump fuel oil or any other desirable fuel for the operation of an internal combustion. This pumping of vthe fuel is accomplished by the pistons such as 44-45 reciprocating within the cylinders such as 6 and 9. The upper'portion of the device which encloses the working end of the pump cylinders,`and the lower portion in which lubricating grease or oil is contained for lubricating the rotarycam, the splines 60, the bearings 61, and the journal 55, must therefore be separated. This )separation is accomplished by the flange 40 ong ;the. main frame 1 and by the felt packing 41 contained in the annular groove in the flange 40. ...It is therefore impossible for the fuel to seep through and to enter the lower portion ofV the housinf`27 where the lubricating oil or grease is contained and it is likewise impossible for the lubricating medium to enter the upper portion of the housing where the operating parts are located for the metering and pumping of the fuel.
An opening. such as 65 is provided in the flange 2 of the frame, and any fuel that may seep along the pistons and cylinder walls down to the anniilar chamber 40' can be thrown out to the outs e. I.
The mechanism contained in and cooperating with the upper portion of the device will be described next.
Near its upper end, the main frame 1 has a serrated flange 66. This serrated flange is represented by a number of semi-circular notches each provided for the reception ofone `of the pump cylinders, such as the cylinders 6 and 9. The cylinders are thus nicely disposed on the main frame and held against .radial displacement on one end by the serrated ,flange 66 and at the other end by the openings which receive the shoulder portions (36 and 37) pf the-cylinders. A closing member 10 having an internal opening 67 is then put on these cylinders. The threaded upper portion 68 of the main frame extends through the opening 67 in the member 10. The bottom side of the member 10 (as seen in Figure 3) is provided with a central boring and with circularly arranged borings, one for each cylinder. The cylinders t each in a correspondingboring in the member 10 as shown in the drawings. Gaskets such as the gaskets 68 and 69 are interposed between the head of the correspondingcylinder and the bottom of the corresponding boring 'in the member 10. It
will be observed that each of these gaskets has al shoulder which engages the head surface' of the corresponding cylinder. I have chosen this parvalves cooperating with the pistons (44 and 45) o 3 ticular form of gasket in-order to-reduce the contacting surface and thereby increase the tightness of the joint. Centrally of each of the borings receiving the cylinder is a boring, in axial extension of the first boring, which extends through the entire member 10. These borings are indicated inthe drawings Figure 3 by the numerals 70 and 71.
Next in assembly is a valve disk or valve plate indicated in the drawings by the reference numeral 72. This is a circular disk provided with a number of bosses (76-77) and through each of these bosses extends a hole, indicated by the referencev numerals 74 and 75. An oil-tight fit between the valve plate 72 and the closing member 10 is obtained by means of gaskets, one cooperating with each of the bosses (76 and 77) and furnishing a tight joint between the valve plate 72 and the closing member 10. The gaskets cooperating with the bosses 76 and 77 are indicated by the reference numerals 78 and 79.
The bosses (76 and 77) extend slightly into the corresponding borings (70 and 71) in the member 10 and represent the valve seats for certain m0 as will be'. described presently. On top-of the valve plate 72 is a circular lter indicated by the referencenumeral 80. This lter is provided with a central and a peripheral flange and these flanges cooperate with suitable 10754 ring shaped gaskets indicated by the reference numerals 81 and 82. Y
The next member is the fuel inlet shell or top cap 23. This cap has a central boring for admitting thev shaft of the bushing member 26, and e110.
circular flange 83 which overlies the valve plate 72 and engages the turned down portion 84 on the closing member 10. The cap 23 has also an angularly projecting inlet member 85 provided with an external thread. Attached to this inlet member 85 may be the fuel line 24 by means of the nut 25.
When the fuel inlet shell or top cap 23 is assembled with the device as ldescribed above, a chamber 86 will be the result, which chamber is 120 divided into two parts by means of the filter 80. Liquid fuel 'entering the devicethroughv` the fuel line 24 and through the boring 87 will therefore K flood this chamber 86 on both sides of the filter 80. 1'25 Solid particles will collect in front of the filter andv the -ltered fuel will enter through the lter into the lower portion of the chamber 86 and will flood the borings such as 74 andv 75 in the valve plate 72;; This is the manner in which the liquid fuel is fed im to the device. i
' It should be remembered for proper understanding of the subsequent discussion of the operation of the device that the chamber 86 is flooded with liquid fuel and that the liquid fuel also Hoods the'135 borings suchl as `74 and 75 leading to the valves which cooperate with the corresponding cylinders and pistons. It is understood that'the borings, such as 74 and 75 are axially in line with the corresponding pistons, such as 44 and 45.
Before entering upon a discussion of the operation of the device I will describe theremainlng mechanism.
The upper part of the main-frame 1 is formed into an axially extending projection 68. This projection is externally threaded for the reception of the closingv bushing 26.. The extension 68 is provided with an internal worm for the reception of the worm 88. The face of this worm is provided 4 Y with la screw driver slot 89, and with an internal key groove.
A central boring 90 extends through the frame for the reception of the'control shaft 91. This shaft, at its lower end, is provided' with a head flange 92. The shaft is inserted from vthe bottom of the device through the boring extendingthrough the rotary cam and through the boring 90 in the frame 1 as well as through the worm V88. The shaft on its upper end is provided with V va key groove 93 and this key groove is brought into register with the corresponding internal key groove in the worm as. The shaft-91 is thus- A Y keyed to the worm 88 and the assembly is completed by means of a nut member 94` which has -two projections 95 and 96 adapted to engage the 'screw driver slot 89 in'the worm88. The nut 94 is threaded on the corresponding threaded portion 97 of the shaft 91 until the projections 95 and- 96. engage the surface of'the worm 88. The
shaft 91 is then dropped whereby the projections 195 and 96 are brought into engagement with the screw driver slot 89 in the worm 88, locking the shaft 91 to the worm 88. The upper end of the shaft 91 is squared as is indicated'by the reference numeral 98. A
Assembled with the top cap or inlet shell 26 are the following parts: A bushing having a flange 99 extends through the closing member 26 as shown. This bushing has a squared opening I 100 for thereception of the squared end 98 of the shaft 91. The upper portion 101 of the bushing,
which extends to the outside, is provided with a key 102 and with a threaded end 29. The control 'lever 30 is provided with a hole and with a key groove for attachment to the portion 101 of the l bushing. The attachment is finally completed by 'movement of the shaft 91 will depend on theft-.1
attaching the nut 31 to the threaded end 29, thereby locking the control lever 30 in engage-l "ment with the member 26." An axial displacement of the lever 30 is thereby excluded, while a rotary movement of this lever is permitted.' The squared openingv 100l in the bushing which co' operates with the member 26 is brought into lregister with the squared end 98 of the shaft 91 and the member 26 is then tightened on the threaded end 68 of the main frame. This completes thek assembly of the device as-far as the same has been described. Y f The following operation will be apparent from the above description of the details andV should be borne 'in mindfor the subsequent discussion of the functions of the device.
The rotation of the control lever 30 will cause .a corresponding rotation of the shaft 91 and, -sin'ce the shaft 91 is keyed to the worm member 88, it .will be apparent that a rotation of the lever 30 will cause a lifting or lowering of the shaft 1 91 within the device. The axial direction of `the' direction of rotation of the control lever 30. The4 radial limit of rotation of the lever 30 will depend on the adjustable axial limit of movement of the worm member 88. The lever 30 limited in its movement to approximately 150 When the lever 30 is rotated, the shaft 91 will move up or down, as the case may be, thereby moving the cam plate' 58 up or down.- 'This axial movement of the cam plate as a consequence of the lifting of the shaft 91 will be understood when it is considered that the shaft extends through vthecam and that the head 92 of the shaft engages the splined portion of the cam. The force of the various springs cooperating with the pistons engaging the cam will tend to keep the cam 58. down. When the lever 3 0 is rotated in the direction to shift the shaft downwardly the cam will follow. However, should the 'control lever 30 be turned to move the shaft 91 in the 105--106. This boring in the shaft extends approximately to the point designatedby the niimeral 107. Lubricating borings, such as 108 may be provided on the shaft v 91 where the journal 55 of the cam engages the shaft in' order to provideforgood lubrication., The boring 105- 106 extending -to the point 107 in the shaft may 100 be used "for lubricating 'the cam and the other internallyV disposed rotating operating parts.
I will now describe thepstructure and operation vof the valves which cooperate with each of the pistons such aspistons 44 and 45. 'The upper portionof the piston 44 has been shown in crosssection Vin order to illustrate the arrangement of thevarious partsof the valve mechanism.
Each piston is turned down in its upper portion and provided with a central boring. This is particularly shown in connection with the piston 44, the turned down portion being indicated ros by the numeral 110 and the central boring in this turned down portion of the piston 44 being inindicatedby the numeral 111.- The valve stem 112 is disposed within the boring 111. The valve plug or head 113 which is integral with the stern 112 operates against the valve seat 76 closing the .supply opening 74 which is in connection with the fuel supply chamber 86. The lower portion" of :thevalve stem 112 is roughened as indicated in the drawings. A tubular sleeve member 114 is disposed around the turned down portion 110 of the piston 44 and is slidable thereon. The boring in the upper portion of the sleeve 114 is enlargedvproviding, a shoulder 115. This shoulder registers with the lower edge of a transverse notch' 116 inthe Yturned down' portion 110 of the piston 44. `A key 117 is disposed in the transverse' notch of the-piston portion'll. The upper portion of the sleeve y114 is closed by a bushing 118 which isprovided with a shoulder. f A spring 119 is dispo'sed between'the valve head 113 and the shoul- V:der on the bushing y11s. This spring tends to keep the sleeve 114 on the turned down portion 110 of the piston 44 as shown in the drawings and to pull the valve stem out of the boring in the piston.
The construction of Vthis valve arrangement cooperating with each piston will be better understood with referencev to- Figure 5 which I will 1,
describe next. v
Referring now to Figure 5, this figure shows, on an enlarged scale, the turned down upper portion :of the piston 44. This portion is indicated by .the reference numeral 110 in accordance with the like reference numeral applied .to this part in Figure 3. It will be seen that this turned down portion 110 of the piston 44 is provided with a centralcboring 111 and disposed in this boring is the valve stem 112.` The valve head is lvalve stem. The sleeve which surrounds the numeral 121. A sloping shoulder 122 is thereby turned down portion 110 of the piston` is shown in fragmentary section indicated by the numeral 114. The sleeve is slidable on the turned down portion 110 and the boring in the sleeve is enlarged in the upper portion as-indicated by the provided which is substantially in register with the lower edge of the transverse notch 116. Now, since the sleeve 114 is slidable on the turned down portion 110 of the piston, it will be apparent that the shoulder 122 will catch the key 117 and press. the key against the roughened portion 120 of the valve stem 112 at the moment when the sleeve 114 moves on the turned down portion 110 of the piston in the direction shown in Figure 5 by the arrow. When the sleeve 114 moves thus, it will lock the valve stem 112 with the portion 110 of the piston. The unlocking can only be accomplished when the sleeve 114 moves or slides along the turned down portion 110 of the piston in the contrary direction.
The operation of the pistons and of the valve cooperating with each piston will now be de` scribed in detail with reference to the Figure 6." This Figure 6 is a somewhat diagrammatic representation, on an enlarged scale, of the operation of the cooperating pistons and valves. A six cylinder pump device is assumed in this gure, that isV to say, a pump device adapted to supply fuel in metered and measured quantities to a six-cylinder internal combustion engine. The device may be of 'the structure shown in Figures l and 2, and the internal arrangement may be the one described with reference to Figure 3.
In order to simplify the explanation of piston and valve operation, I have shown the valve seats, and also the operating cam in straight line representation. Only a fraction of the cam, namely the cam dwell portion, is shown as indicated by the reference numeral 59 in accordance with the same reference numeral applied to this cam portion in Figure 3. Itfwill be understood that the cam is in reality a circular rotating disc.4
The valve seat plate which inreality is a circular plate such as indicated by numeral 72 in Figure 3 is also shown ina straight lineplane, and the same reference numeral 72 is 4applied thereto. This valve plate 72 has as many valve seats as there are pump cylinders. The valve seats extend in reality intov borings within a closure member such as the member 10 in Figure 3. The borings act in the nature of a chamber to which liquid fuel is admitted by the valves. It is assumed in Figure 6 that the rst valve seat corresponds'to the valve seat 76 shown in Figure 3 in axial alignment with the piston 44, the upper portion of which is represented in cross-section. The next two valve seats aredesignated by numerals 125 and 126.
The valve seat 77 corresponds to the valve seat 76 in the cirular structure Figure 3. The remaining valve seats disposed.. inthe (circular) structure between the valve seats 76 and 77 are designated by numerals 127 and 128.
The cylinders are omitted, and only the upper portions of the pistons in axial alignment with the valve seats are shown. Accordingly, the first piston shown in the drawings Figure 6 on the left side, is the (upper part) piston 44 corresponding to piston 44 of Figure 3. The piston 45 is shown in alignment with valve seat 77 and corresponds to the piston 45 in Figure 3. The (upper portion of) other pistons are designated by reference numerals 129 to 132, inclusive.
In the lower portion of the drawings Figure 6 is shown the cam 59, and itis assumed that this cam moves (in rotating) in the direction of the arrow, i. e., from right to left in Figure 6. It may be mentioned here that the direction of movement of the cam is immaterial in practice, but a definite direction of movement is assumed for the purpose of convenient description. Auxiliary pistons ride on the cam. -These pistons can reciprocate or shift axially within the corresponding holes in the lower flange of the main frame of the device and within the sleeve on the piston, as particularly` shown in Figure 3.
Part of the auxiliary piston`42 is shown in Figure 6 and designated by the same reference numeral. Part of the auxiliary piston 43 is shown likewise. 'Ihe remaining auxiliary pistons cooperating with the pistons 129 to 132, are marked by numerals 133 to 136, inclusive.
The operation will bedescribedwith particular reference to Figure 6, but Figure 3 should be consulted for certain details not shown in Figure 6. The previously mentioned operation of the auxil` iar`y pistons relative to the main piston should be recalled, namely, that these auxiliary pistons have a constant stroke depending on the dwell 59 of the rotary cam 58. The downward stroke of the main Y pistons is fixed due to the sleeves such as tlre sleeves 52 and 53 shown in Figure 3. The flanged heads on the pistons will engage the sleeves as is apparent from ythe position of piston 45 relative to the sleeve 53. The flanged head 47 of the piston 45 rests on the sleeve 53. In case the cam is shifted axially by the actuation of the control lever 30, the auxiliary pistons will be lowered or raised relative to the main pistons.
For example, if the cam 58 is lowered from the position shown-in Figure 3, the result would be that all auxiliary pistons 'would move downwardly, following the movement ofthe cam. The pis- 4tons which engage the plane ofthe cam, such as the piston 43 would move down and the distance 137 (Figure 3) between the auxiliary piston and the head *of the main piston 45 would increase. The4 main piston remains in the position shown because the head 47 rests on the sleeve 53.` The auxiliary piston which is in engagement with the highest point o f the cam dwell 59 would also follow the downward motion of the' cam. However,- since this piston is in its highest position and has lifted the main piston 44, the' main piston would also follow the movement and the distance 138 (Figure 3) would decrease. This distance 138 signies the stroke of the piston 44 (and also the remaining pistons) at the particular cam setting. A lowering of the cam from this setting therefore means a decrease in the stroke of the main pistons, and raising of the cam will cause a corresponding increase.
In case the cam is lowered to such extent that the distance 138 is completely obliterated, that is to say, that the main piston will rest on the sleeves such as 52, 53 in lthe highest position of the auxiliary piston, there will be no pumping of fuel; the main pistons will not respond. The auxiliary pistons will still have their constant stroke de- -pending on the cam dwell 59, but will-reciprocate idly within the space 137 which is now increased im to the amount of the cam dwell 59.
In the position shown in Figure 3, and, in fact, in any effective working position, the auxiliary pistons will always operate with constant stroke,
but only part of the stroke will be operatively.
f within which the upper portion of the piston reciprocates. In the moment when the piston moves UD. valve must close, so that the piston can displace the liquid fuel in the corresponding space and eject the fuel through the outlet connection. This opening and closing of the 'valve cooperating with each of the cylinders and pistons is accomplished by means of the novel valve lock which I have previously idescribed particularly with reference to Figures 3 and 5;
With the above explanations in mind, I will enter upon a description of the function of the device with particular reference to Figure 6, but, as I have said previously, Figure 3 should be consulted for details not shown in Figure 6.
Now, let us assume that the cam rotates thereby moving the dwell 59 in the direction indicated by the arrow in Figure 6. The auxiliary piston 42 is now positioned on the plane of the cam. The valve head 113 is in engagement with the valve seat 'I6 closing the opening 74. The chamber '10 (Figure 3) isI flooded with liquid fuel. The
cam rotates and the cam dwell will lift the aux.`
iliary piston to a position as shown in connection with the second piston 133. Let us assume thatthe working stroke begins at this point. |I'he piston 441129) ywill move upwardly and will dis place the liquid fuel in the corresponding chamber, electing the fuel through the outlet channel such as 139, as shown inFigure 3. In the further movement of the cam, the auxiliary piston will finally take the position shown in connection with the piston 134. The highest point of 'the cam dwell 59 is somewhat flattened as is indicated by the dotted line 140. The piston will therefore come to a'stopin its upward motion. It will remain in this position for the length of 'the nattened portion 140 of the cam dwell. Since the sleeve 1141s slidable on the turned down portion 110 of the piston, and since the inertia of the sleeve overbalances the force of the spring 119, the sleeve 14 will have a tendency to continue in the `motion of the piston and will compress the spring 119. as is shown in connection with the piston in the highest portion of the cam.
The shoulder 122 will engage the key 117 and will press the keyagainst the roughened lower portion 120 of the valve stem. The sleeve 114 remains in this position due tothe inertia of the material, which action lwill be understood when it is considered that the inertia of the sleeve 114 overbalances the spring 119. The valve stem 112 is therefore locked in engagement with the turned down portion 110y ot the piston (130). The working stroke is completed and the quantity of fuel which was previously admitted into the chamber (Figure 3) is elected v through the outlet duct 139.
vThe cam continues to rotate and the cam dwell moves away from under thepiston so that the piston comes-into the position shown in connection with the auxiliary piston 43. The cooperating piston moves downwardly. It takes the valve along due to the locking of the valve stem 112 in engagement with the turned down-portion 110 of the piston. The inlet opening (such as i. e., when it starts its working stroke, the
to the operation of the cam and nnally assumes the position shown in connection with the auxiliary piston 135. The valve is completely open and liquid fuelA is admitted into the cylinder pumping chamber.
Thel axial movement of the main piston will come to a sudden stop, during the return movement at the moment when the flange -of the main piston engages the sleeve of the corresponding auxiliary piston. The sleeve 114 due to the momentum of the material will tend to continue in the downward motion and 4will assume ,the position shown in the drawings in Figure 6,
(piston 131) releasing the key 117 and thereby releasing the valve stem 112 from locking engagement with the piston. The force of the spring 119 will now become effective and will move the valve upwardly to close the corresponding valve seat opening as is shown on the right side of the drawing Figure 6. l
The v alve in the piston sition in which it originally was. Liquid fuel has been admitted to the cylinder chamber; the auxiliary piston rides on the plane of the cam, and when it is raised to the position shown in connection with the auxiliary piston 133, the working stroke will begin and the liquid fuel will be ejected thorugh the outlet duct asl described. When the piston arrives again at the' highest point of the cam dwell 59, which is flattened, the sleeve will again continue -in the working stroke movement, will compress the spring and will lock t working stroke. The cycle is repeated as long as' the device is in operation.
It will b e seen from the above description of the valve action that this' cooperating piston and valve structure accomplishes the desired purpose in novel manner. The sleeve on the turned down portion of the piston acts in the nature of a chuck for locking the valve to the piston at the .end of the working stroke, and for releasing the locking engagement at theend of the return stroke. The valve is positively opened and liquid fuel is admitted during the return stroke, and at the end of the return stroke, the valve is released and closes the inlet port" due to the spring force. The'spring need only be strongenough to lift the v weight of the small valve stem and valve head. The'weight of the sleeveis many times the force of the spring. I therefore'utilize the inertia of the material for accomplishing the valve action,
and this utilization of natural forces enables me to achieve a proper and positive action in this device, in a novel manner, and with less effort than was thought pomble in the past.
Attention is called at this point -of the description to Vthe length of the pump pistons. A seeping of f uel along these long pistons will be pracisnowagaininthepo-Al accomplished during the next 'i tically negligible even in case Vof highest pres- 'I sures. It will also be realized that'the construction of the pump relative to the volume handled can be readily modifled without any effort. The borings in the pump cylinders can be enlarged,
-or rather to say, other cylinders with larger borings can be substituted together with otheripistons, and inserted in place of the pistons shown.
This will increase the capacity of the-pistons for a proportionately larger engine.
the cylinders of the engine is thereby accomplished gradually, during the compression stroke j of the engine pistons.
The structure of the valve cooperating with each pump piston may, of course, be modified in various ways. The essential thought resides inA the utilization of the natural forces, that is, in the inertia thatis in the material. In the Figures 7 to 10 inclusive are shown two further embodiments of cooperating valves and pistons which I will describe next.
In Figures 7 and 8 I have shown the upper part of a piston, designated by the reference numeral 140.. The upper portion consists of tvo cooperating sides 141 and 142, whereby the part 142 is loosely attached to the part 141. The arrows at the left of Figures 7 and 8 indicate the downward and upward motion of the piston, respectively. The cooperating parts 141 and 142, the rst being integral'with the piston 140, are provided with a cavity inl which are disposed rings as indicated by the reference numerals 143'to 147, inclusive., The valve comprises a stem 148 and a head 149. The latter may cooperate with a valve seat to close or to open a port leading to the cylinder chamber.k
Let us now assume that the piston 140 moves upwardly as is shown in Figure 8. The valve at this moment is closed. At the end of the working stroke, the part 142 will continue to move due to the inertia of the material; and will assume the position relative to the part 141 ofthe piston 140 in which it is shown in the drawings Figure 7. The rings 143 to 147, inclusive, will be tilted within the cavity of the parts 141 and 142 and will thereby grip the roughened val-ve stem 148. The
fpiston`140 moves then downwardly in the direction shown by the arrow on the left of Figure 7 and, since the valve stem 148 is locked in engagement with the piston, the piston 140 will take the valve 149 along, thereby opening the supply orifice. At the end of the return stroke, the part 142 will again return to the position shown in Figure 8, thereby releasing the valve 149. The closure of the valve may be accomplished by the use of a spring as in the previous case.
In Figures 9 and 10 is shown a further modiilcation which `may be employed. The end of the piston such as the piston 150 is turned down at 1'51 and provided 4with a chuck head 15 2. A
' boring is provided vin the turned down portion 151 as shown, and a longitudinal slot gives resiliency to the upper portion of the piston. A chuck sleeve 153 -is slidably disposed on the turn'ed down portion 151, and the upper part oi.' the chuck portion 153 is turned in conically at 154 for engagement with the conical back of the head 152. -The valve stem 155 is disposed within the slotted opening of the piston 150.
Assuming now that the piston 150 moves upwardly in the direction of the arrow shown on the left of Figure 10, with the valve closed, the piston will Adisplacethe liquid fuel and eject the same in Figure 9. The conical surface 154 engages the corresponding'surface of the head 152 of the piston, thereby locking the resilient sides of the slotted head yand gripping the stem 155. The
valve is now locked to the piston. During the downward motion in the direction of the arrow shown on the left iniFigure 9, the valve-'will be taken along by the piston due to the locking of i the chuck sleeve 153, and the valve" will open and liquid fuel will be admitted into the corresponding cylinder chamber. At the end of the down stroke, the chuck sleeve will move due to the momentum of thereturn motion of the piston and will assume the position as shown in Figure 10. releasing the valve stem 155. The valve can now move to close the supply orifice in a manner as was previously described.
It will be understood that the embodiments shown in Figures 7 to 10, inclusive, are merely diagrammatic representations of additional structures which may be used in practice These examples do not by any means exhaust the ideas of modifications and other -embodiments which may occur to one experienced in the art and directed by my teachings.
The valve head or valve plug which I have shown as a plate or nat disc may of course be rounded', or may be made in conical plug form, if desired.
I. will next describe the check valve which is disposed in each of the outlet connections of the device.
Threaded outlet extensions are provided on the closure member 10 in radial alignment with the corresponding cylinders. Two such outlet ex,
tensions are -shown in Figure 3 and designated by the numerals 156 and 157. Each extension is provided with an external thread and with an outlet duct suehas the duct 139 shown in connec-V .tion with the extension 156. The extension 156 posed at the bottom of this socket boringis a v gasket such as is indicated by the reference numeral 160 in connection with the extension 156. A valve seat member 161 is disposed in the socket opening engaging the. gasket 160. This member has an internal boring 162 and a threaded head 163 which is ilattened on itsv sides in order to permit the passage oi fuel. A gasket 164 is provided on the flange of the member 161 and engages a ange 166 of the member 17.which is held in assembly with the valve seat member 161 and with the extension 165 by means of a nut such as the nut 11. AThis member 17 is provided with l`a boring 1,68 and a larger boring 169. A valve housing 170 is `disposed within this large boring 169 as shown. The valve housing is provided with an internal threadfor engagement with the 'external thread on the valve seat head 163 and the in the bottom boring of the valve housing 170.
A spring 175 tends to close the valve 173 in engagement with the valve seat on the face of the head 163.
The above structure is shown in enlarged crosssection in Figure 4 which is taken along the lines 4--4 in Figure 3. It will be seen that the valve housing in slottedat its end as indicated by the numeral 172, and that this slotted end of the valve housing engages the threaded portion 163 of the valve seat which is provided with the atted sides. The fuel entering the valve, housing can therefore be displaced through the slotted end and can flow along these flatted sides of the valve seat.
When the cylinder 44 operates on its working stroke to eject the liquid fuel through the duct 139, the fuel will enter through the hole in the gasket 160 and through the duct 162 in the valve seat member 161. The pressure of the fuel due to the operation of the piston 44 will displace the valve 173 against the pressure of the spring 175 and the fuel will enter into the valve'housing 170. It will leave through the slotted end of the valve housing which is in engagement with the valve seat head 163, the sides of .the head 163 of the valve seat being flattened in order tol permit an' easy passage of the fuel. The fuel will thus flow around the valve housing 170 and will enter the outlet duct 168 in the member 17. Attached to the member 17 by means of a suitable screw joint or the like is a corresponding fuel line leading to the atomizer in the corresponding engine cylinder. A check valve arrangement of the structure described above is disposed in all the fuel outlets on the memberl 10 in radial alignment with the corresponding cylinders.
The operation will be easily understood from the above detailed description of the mechanism. However, 'for the sake of completeness, I will briey review the operation below so that the device may be correctly understood. The
' fuel is fed to the deviceby the fuel inlet line 24 and thus to the supply chamber 68 on both sides of the filter 80. In the continuous operation of this-device it must be assumed that the various channels and`ports are flooded with liquid fuel. Therefore, it is merely necessary to displace the fuel rather than to pump it intothe device by the action of the pistons.
Since the supply chamber 86 and the supply ports such as 74 and '7 5 of the various cylinders are flooded with liquid fuel, thefk operationof thepistons merely causes a displacement of the fuel. When the cam 58 rotates due to the rotation of the driving member 28, it will actuate the auxiliary pistons, and, according to the adjustment ofthe control lever 30, the auxiliary pistons will actuate the main pistons such as 44 and 45. The main pistons will cause the opening of the valves of the supply ports in a manner as was particularly described in connection with the Figure 6 and the fuel will enter the chambers such as 70, while the pistons go down. The `valves will then close and during the working stroke of the pistons, the fuel within the chambers such as 70 will be displaced and will be ejected through 'the corresponding ducts suchl as 1 39. 'Ihe pressure on the fuel will cause an opening of the check valves such as 173A in the corresponding outlet opening and the fuel will ow from the duct 162 into the v alve housing and around the slotted end of thevalve housing joining the flattened sides ofthe corresponding `valve seat, and partially also through the boring in which the valve stem (174) reciprocates,
entering finally the outlet duct (168) which isin connection with the pipe line leading to the 'atomizer on the corresponding engine cylinder.
When it is desired to supply less fuel for the loperation of the engne,.a11 that is necessary is to turn the controlv lever 30 in a direction to shift the shaft 91 downwardly, whereby the cam 58 will follow the movement of the shaft due to the pressure of the auxiliary pistons on the cam. The stroke of l the main pistons will thus ply `less fuel through the pipe lines-t9 the en gie cylinders., When it is desired to supplyiriore fuel, in accordance with the requirements .of speed and load, the control lever will be rotated in the contrary direction, lifting theshaft -91, thereby also lifting the cam 58 due to the fact that the head 92 of the shaft engagesthe face of the splined portion 60 of thecam, and. the cam` lwill be raised,` increasing thereby the effective stroke of the main pistons. l
It will be seen that the auxiliary pistnsare directly in sliding engagement with the cam. If desired, this arrangement may be modified, for example, in accordance with the struct shown in Figure 11.
Referring now to Figure 11, this figure shows a fragmentary portion of a -cam such as the cam 58, designated in Figure 11 by the reference numeral 58.'. The lower end of a pump cylinder is shown in this figure anddesignated by the numeral 180. A piston 181 reciprocates within this cylinder 180. Thelower end of this piston has a cup-like head 182 having an opening for receiving the auxiliary piston 183. The head 182 o f the main piston at the end of the return stroke rests on the flange 40 of they main frame, corresponding to the flange 40 in Figure 3. The 'flange is also provided with an annular groove for receiving-a felt packing 41' in order to prevent the communication of liquidl ful which may seep along the pistons with the lubricant. contained in the lower portion of the housing, a portion of which is shown' at 27'. A spring 184 engages the head 182 of the main piston 110l 181. and at the other end, this spring l184 may engage a flange. or shoulder on the cylinder 1'80.
liliary piston downwardly away from the main piston 181. A lowering pf the cam 58' will therefore cause a corresponding lowering of the auxiliary pistons, while the main pistons remain in the position as shown in connection with pistonv 181.
The operation is therefore exactly the same as in the previously described embodiment'. The modification resides chiefly in the provision of a roller or wheel 185- at the end of each auxiliary. piston. In the previously described embodiment, the auxiliary pistons slide directly on the cam, while in this modication each auxiliary piston is provided with a roller..` A
A slot 187 is provided in the ange 40' in the main frame adjacent the opening in which the corresponding auxiliary piston reciprocates, and each auxiliary piston has a` lateral projection such as the 'projection' 188 which slides in this slot. 'I'he purpose f the slot and the corresponding projection of the piston is to x the piston radially`while permitting its longitudinal movement. This is necessary in view of the fact that a roller is provided at the end of the piston which cooperates with the cam. The auxiliary piston must therefore be prevented from rotating. 'It will be understood that numerous modifications may be devised above and beyond the-modifications of certain parts. which I have shown and iso described. I therefore want to have it under- 150 stood that I do not desire to vbe limited in the application of the invention to the precise structure or structures shown and described in this specification, but only to the meaning and scope of the claims which follows. I have expressed in these claims what I believe is new and distinguishing in the art.
What I claim as my invention is:
1. In a high speed fuel pump for internal combustion engines, a cylinder, a piston therefor, an axial boring in said piston, a valve having a stem disposed Within said axial boring, a key member in the-wall of said piston, and a sleeve on said piston for actuating said key member to lock said valve stem to said piston upon the termination of the working stroke thereof.
2. In a fuel pump for internal combustion engines, a cylinder, a piston therefor, an axial boring in said piston, a valve member having a stem and a plug, said stem being disposed within said axial boring, an inlet port for said cylinder, said plug being adapted to close said inlet port, key means for locking said valve member in engagement with said piston and sleeve means on said piston for actuating said key means upon the termination of the working stroke thereof and for releasing said valve member from locking engagement with said piston upon the termination of the return stroke thereof whereby said valve member will open said inlet port during the return stroke and close said inlet port during the working stroke'of saidpiston.
3. The unitary assembly of a fuel supply device for an internal combustion engine, comprising a frame, a plurality of cylinders circularly disposed on said frame, a piston within each cylinder, a single rotary cam forl actuating said pistons, means for altering the position of said cam axially relative to said pistons to determine the working stroke of said pistons, a member for securing said cylinders in circular assembly on said frame, fuel inletA chambers in said member one for each cylinder and in axial alignment therewith, fuel outlet means extending laterally from said member, a valve plate cooperating with said member, valve seats on ,said plate extending individually into said inlet chambers, a top vshell for said device, a circular filter within said shell, a fuel inlet on said shell, and a single means cooperating with said frame for securing said shell, said valve plate, said member and said cylinders in position.
4. In a pump, an inlet port, a piston, a valve for said inlet port, said valve having a stem disposed slidably in' said piston, a sleeve onsaid piston, a spring disposed between said sleeve and said valve and tending to pull said stem from said piston, and means actuated by said sleeve for locking said stem to said piston upon the end ofthe working stroke thereof, the piston pulling said valve locked thereto during the back stroke to open said port, and for unlocking said stem upon the termination of said back stroke, said spring pulling said valve to close said port.
5. A fuel pump for internal combustion engines comprising a casing, a plurality of cylinders disposed symmetrically around said casing, pistons for said cylinders, a shaft extending centrally through said casing, a cam for actuating said 8l pistons, said cam being rotatably carried on said shaft, means secured to said casing and directly engaging said cam for rotating the same to actuate saidvpistons successively, and rotatable lever means disposed centrally of and outside said casing for shifting said shaft longitudinally to alter the position of said cam relative to said pistons for determining the stroke of said pistons.
6. A fuel pump mechanism of the class described, comprising a frame, a plurality of cylinders mounted symmetrically on one end of said frame, pistons for said cylinders projecting from said frame at one end, a rotatable cam for actuating said pistons, said cam being journaled within said frame, a housing for attachment to said frame to envelop said cam, a partition on said frame disposed within said housing for separating said cam from said cylindersto avoid seepage' of fuel into said housing, means mounted in said housing and directly engaging said cam for rotatl ing the same, a shaft extending centrally through said cam, a head on said shaft engaging said cam at one end thereof, a worm member disposed within said frame and cooperating with the other end of said shaft, and rotatable lever means mounted outside said mechanism and centrally thereof for actuating said worm to move-said shaft longitudinally for valtering the position of said cam relative to said pistons to determine the stroke thereof.
7. A unitary fuel pump device` comprising a cylinder, a piston therein, means for biasing said pistonv in the direction of the return stroke thereof, a stop for defining the extento'f the return stroke, a hollow auxiliary piston disposed in axial alignment with said first piston and adapted to actuate said iirst piston, spring means in said auxiliary piston tending to move the same away from said first piston, a rotatable cam for directly actuating said auxiliary piston, means directly engaging said cam for rotating the same, a shaftextendlng centrally through said cam, a flange on said shaft engaging one end of said cam and rotatable lever means on said device for longitudinally moving said shaft to alter the position of said cam relative to said piston for determining the stroke thereof.
r FRITZ STEPHAN.