US1816157A - Injector - Google Patents

Description

July 2s, 1931.

P. l.. scoTT 1,85157 INJECTOR Filed June 16, 1926 5 SIeets-Sheet l lq v July 28, 1931. P. r.. scoTT 1,816,157

INJECTOR Filed June 16, 1926 5 Sheets-Sheet 2 P. L. scoTT July 28, 1931.

INJECTOR Filed'June 16,- 1926 5 sheets-sheet s July 28, 1931. p. L SCOTT 1,816,157

" l INJEcToR filed June 16, 1926 5 Sheets-Sheet 4 P. L. SCOTT July 2s, 1931.

INJECTOR Filed June 16, 1926 5 Sheets-Sheet 5 Psa-median 2s, 1931 UNITEDy STATES- PATENT orner.

P HILIP LANE SCOTT, 0F CHICAGO, ILLINOIS, ASSIGN'OB T0 SUIEB-DIESEL TRACTOR CORPORATION, OF LA PORI'IJIEI,` INDIANA, A ('JOIIIEOIRATION 0F NEW YORK minoren Application led June 16, 1926. Serial No. 116,272.

This invention relates to means for delivering liquid under high pressures and, if desired, intermittently at very high frequency and particularly for doing so without the use of mechanical drives and especially without the use of such heavily loaded drives. While the invention has many applications, it is illustrated here particularly in several forms adapted for use in connection lwith internal combustion engines of the injection type. By this is meant engines of the Diesel and the modiied Diesel cycle in which the fuel is injected into the engine. i

One object of the invention is to provide means fordelivering liquid under very high pressure, intermittently at hi h frequency without any metal to metal driving contact at the delivery end. Another object is to provide means for supplying such liquidin very small controlled quantities with great accuracy. Another object is to provide means for delivering such liquid in very` small controlled quantities with great accuracy. Another object is to provide means for delivering such liquid to the separate cylinders of an engine while using a single mainA pressure creating unit irrespective of the number of cylinders. Another object is to provide an apparatus of the type above suggested in which a single main pressure creating unit may be used to operate a plurality of final injection units which may e located at. a considerable distance from such main unit. Other objects will appear from time to time throughout the specification and claims. The method may be used to step up liquid pumping pressures. The invention is illustrated more or less diagrammatically in the accompanying drawings in which: l

Fig. 1 is a plan view of the combined pump and injection;

Figure 2 is a vertical cross section taken on line 2--2 of Figure 1, with parts in elevation;

, Figure 3 is a transverse cross section on an enlarged scale, taken on line 3-v-3 of Figure 2 and illustrating in detail a number of the injection units.;

gine.

Figure 4 is a diagrammatic elevation illustrating the` driving gearing connection; Figure 5 is a fragmentary'vertical cross section on a further enlarged scale illustrating the connection between the two plungers in the injection unit Figure 6 is a modiied form generallyl unit is formed of a member B which is provided with a central cylindrical bore B1, an enlarged lower bore B2. B3 is a driving shaft for the pump driven from any suitable power source. Where the apparatus is used 1n connectlon wlth 'an engine, this pump will preferably be driven by such en- B4 is a cross head provided with an upwardv depression Bs within which the enlarged head B6 of a pump plunger B" is located. It is held therein by a retaining gland B8. The shaft B3 is provided with an eccentric B1o about which a collar B11 is mounted. The collar is joined by means of a connecting rod B12 to a wrist pin BL3 rpositionedin the cross head B4.

C is an intake or suction passage within which is mounted a suction valve C1 normally held seated by a spring C2. C3 is a discharge passage within which the discharge or outlet valve C* is seated and nor mally held on its seat by a spring C5. Itv

communicates with a chamber C from which an outlet connection C7 leads to a.

high pressure pipe or conduit'Cs. Cis a low pressure or returmpipe or conduit which communicates with the intake passage C. Thus, the circuit of fluid is into the pump,

out through the pipe C8,through the injec-v tion unit or units inthe manner described belowand back through the conduit C into the pump a ain and the driving Huid is th circulated a out in a closed circuit. Y

Dis an overflow connection which communicates with the chamber C". It is conpressure side.

.operated and Huid is thereby .permitted to pass through the pipe D5 and from the high pressure side of the pump, back tothe low In the form shown in Figures 1, 2 and 3, the injector units are four in number. They are all grouped together in a single housing E. Rotated within this housing are two tubular distributor rotors located in a cylin-l drical passage formed in the housing E. E1 is the high pressure rotor and the conduit C8 communicates with it through a suitable itting and supplies it with the liquid under pressure.. E2 is a corresponding low pressure rotor and it discharges into the conduit C9. Each of the rotors is provided with four Vopenings or perforations spaced progressively about the rotor 90 apart. The rotor E1 is provided with the several perforations or ports E3 and 'the rotor E2 is provided with the perforations or ports E4.

One of the ports in each rotor is effective for one injector unit which acts upon one engine cylinder. A description of one such unit will suilice foriall. The housing E is provided with one or more central bores F, each of which has a reduced portion F1. Communicating with the upper art of the bore F are two lateral passages 2 and F1,

the latter preferably being larger than the former. Communicating with the lower part of the bore F are two similar lateral passages F1 F5 the latter being larger than the former. Connecting the passages F2 and F1 is a vertical passage F6, which is preferably of the same .size as these two passages. Connecting the passage F5 and F2' is a vertical passage F7 preferably Iof the same size as the two last mentioned lateral passages. Each of the vertical passages passes through the cylindricalchamber in which one of the rotors lies and ilow of liquid through the various passages is thus controlled and limited by the position of the rotors. .F8- is the larger portion of a differential plunger and it lies within the bore and reciprocates therein. F9 is the smaller end of the differential plunger and it lies `withinthe bore F1. The two are provided at their contacting ends with rounded portions Flo and are held together by a loose collar F11 and pins F12. The collar F11 making a loose t with the abutted threaded ends of the di'erential plunger permits slight relative movement of the parts without setting up undue strains and without binding of the parts. F11 is an adjusting plugwhichmay be raised or, lowered to limit the downward movement of the plunger.

In one form, this plug is controlled by a cam F14 on a rod F15 which ma vbe moved in and out by a lever F16 whlch may be 1 locked in position upon-a quadrant F1". What has been described above relates wholly to the drivingof the injection means and the driving fluid alone is circulated through the assages, chambers and conduits describe The actualfuel supply is wholly independent from these conduits and passages and it will now be described.

Running longitudinally through the upper part of the housing E is a fuel. supply chamber G to whichl fuel -is supplied by means of a pipe G1'. From the supply chamber G a passage G2 runs to. each of the rei duced bores F1. The opening of the passage is controlled by an intake yalve G8 which is normally held seated by a spring G4. .The valve is mounted in a cage G"s which is removably held in position by a plug G6. G1 is a discharge passage which through a tting G8 and a conduit G1 communicates with the injector or otherl point where the inj ec'tcd liquid is to be treated. Located within this passage is a valve G1o seated within a valve cage G11 and normally held seated by a spring G12. A downward reciprocation of the plunger lifts the intake valve G8 and draws fuel from the chamber G into the bore F1. The upward reci rocation of the piston closes the valve G3 an after pressure is built up opens the discharge valve G1o and Huid is forced outward to its point of use or further treatment.

I shall now describe the driving mecha- `nism for the rotors.

Each of the rotors is provided at its closed end with an extending stem, the rotor E1 having the stem E5 and the rotor E2 having the stem E6. Mounted on the shaft B11 is the driving pinion B11. It meshes with a larger E7 on the s'haft E5. This shaft 'carries a small driving pinion E8. It meshes 1 with another pinion E9 on the shaft E6. Thus the two rotors are driven `in opposite directions at the same speed.

While in the forms shown the rotors and injector units are in the same housings, that it in the same main block,for some purposes it might be preferable to have` asingle housing in which the rotors are mounted and have separate injector units located elsewhere, possibly each o'ne adjacent the engine cylinder which it serves, and 'in that case,4

of coursev the rotorsv and the injector units would not b e in the same housing. My invention is therefore not limited specifically to a structure in which the rotors ,and injectors are in the same housing.

In Figure 6 which shows 'merely a detail of the returnimechanism for a device generally similar to that shown in Figure 3. The passages F2 F8 and F6 F7 are omitted for each injector unit. The return of the member FB is accomplished therefore not by fluid pressure but by la spring F1l5 which is located above the plunger F8 `and at one end bears upon it and at the other end upon the upper end of the bore F within which -the plunger F8 is located. The spring being compressed when the plunger is forced upward byfluid pressure, returns the plunger when it is freeto do s by the reduction or withdrawal of thepressure beneath the plunger. F16 is anair vent communicating with the interior of the bore F and above the piston. This vent serves to equalize the air pressure within the bore above the piston-with that of the outside air.

In'Figure 7 a further modified form for returning the plunger is shown. This form of the device differs' from the form shown in Figure 3 in that the passages F2 Fs and Fo F7 are omitted vand further in that the upper part of the bore F is open to the air. The limiting device shown 1n Fi ure 3 and including the parts F13 and Fi* 1s also omitted.

In place of the iston or plunger F8 a generally similar plston H is used. It is positioned within the bore F in the same 'mannen It is provided at its top with a reduced extension H3l which carries preferably a reduced iston or plunger H2. An opening H3 is ormed in the side of the housing E opposite each of the bores.

'J J are bracket arms pivoted concentrically with the shaft E". These bracket arms are joined by a lon itudinal member J1 and they are thus heldin the same osition and may ,be moved together. lJ2 1s a bracket fastened 'to the housing E and located generall centrally of the longitudinal member 1. J? is a stud projectin from the bracket upon which is mounted gor rotation a cam J4 which is joined to an arm J 5 by means of which it may be moved. Thecam J 4 bears against the longitudinal member J1 and as it is rotated, moves the member rotating it and the bracketarms J about a point concentric with the shaft E5.

K is a cam shaftpivoted on the arms J. J. In the form here shown there are on the cam shaft four cams K1. They are preferably placed 90 apart. This arran ement, of course, would be different if a di erent type of engine were used or if an engine with a different number of cylinders were used. K2 is a rocker arm projecting inwardly through the opening H3 and pivote'd therein on a shaft K2. One of the said rocker arms ,is

provided for each of the pistons H and in the form here shown a .single rod K3 would extend through the casting and furnish the bearing foreach of saidrocker arms. At one end of the rocker arm K2 is provided with a rounded part K4 which is positioned within a cavity K" in the member H1. At

its other end the rocker arm K2 carries a nose K6 which is contacted by the cam K1 in their rotation. It is obvious from the construction shown that as the cam shaft rotates the cams upon it contact the noses K and thus rock the rocker shafts K2' and so return the piston H. The upward movement of the piston is brought about by hydraulic pressure in the same manner as that described above in connection with the other forcing the piston upward and the process by which this is done is the same in all' forms of the invention, and the function of the cam and rocker arm assembly shown in Figures 7 and 8 is merely to return the piston in lieu of the hydraulic return shown in Figure 3'.

On the shaft K is a driven ear K. It is in mesh with the driving gear 8 and driven b it. .yAlth'ough I have shown an operative de- `vice, still it will be obvious that. many vforms of the invention. The mechanism for X is a tension spring fastened at X1 to the arm J and fastened to the projection X2" fixed on the housing E. The tension of the springs tends to rotate the cam shaft and frame which carries it downwardly and to hold it against the cam J 4 to prevent accieum position.

The use and operation of my lnvention are as follows:

In the form shown in Figures 1 to 5'v ini elusive, thev operation of the device in connection with an internal combustion engine is as follows: The driving shaft is connected with the engine and is driven thereby in timed relation thereto. The liquid in the primary pump unit is circulated about in a closed circuit. Oil will preferably beused for this purpose. This oil is forced from the high pressure side of the pump to the' rotor E1 which is always full of high ressure oil. As one of the perforations o the rotor E1 registers with a passage F", high pressure oil is discharged from the Arotor, moves through communicating passages and is admitted to the upper end of the large of the rotors with rela bore F. The timing tion to eachother 1s such that at this time the rotor E2 is closing the passage F" and since this high pressure oil cannot esca e into the low pressure rotor it- -forces t e plunger down into the position shown in Fig. 3, thereby drawing fuel into the chamber G2 from the supply port. As the rotors continue their rotation, the port Ea is moved out of register with the passage F8 and the f port E4 finally moves into register with the passage F, thereby being in position to per- .completed approximately one-half a revolution, is pointed down and in full register with the passage F4. Thus a high pressure oil is again discharged from the rotor E1.

. This time, however, it is discharged. on the under side of the plunger F8 and fills the passages F4L and F5. Escape upward through the passage F7 is barred by the position of the rotor E2 and therefore this high pressure oil forces the plunger upward and since the passages communicating with the upper part of the bore F are open through the port E4 to the interior of the low pressure rotor E2, the oil is forced from above the plunger into this rotor and out through it along the conduit C", back to the intake or low pressure side of the mainv pumping unit. As the injector plunger rises, it closes the intake valve G3, opens the valve Gr10 and forces out a charge of fuel to the engine injector nozzle or other point of use for Vfurther treatment.

While the operation of a single unit has been described, itis clear that the other units operate in exactly the same manner following each other in regular order. In

" Athe. form shown, the ports in the rotors are spaced 90 apart, running progressively` from one end to the other of each rotor and thus the injector units operate, one after the other, in the order indicated. The amount of travel of the injector plunger is determined by the seating of the governing or p adjusting plugs. The Aadjustment or seating of these parts may be carried out manually, as in the form-shown in :Figures 2 and 3, or it may be governor controlled.

The operation of the device as shown in the moditedforms of Figures 6, 7 and 8 is generally the same as that described in connection with the fprms of Figures l land 3. The rotors are driven. by the same mechanism and operate `in the same manner. The ypiston is forced upwardly in the same manner by hydraulic pressure and distributed and controlled bythe rotors, and the injector units operate in the same manner as that y described above in connection withFiguresy 1 and 3. Inl the return movementl occurs i the onlydifference. In the form shown in Figure 6 return movement is by a spring.

-"Inthejform shown in Figures 7 and 8 return movement is mechanical and is caused by rocker arms which are rocked by the cam shafts which are themselves driven in phase with the driving mechanism of the rotor. The rocker armsthus at approximately the time that the pistons have completed their 4full upward stroke, are'actuated by the cam to depress them. The lengthof the excursion of the plunger is variably adjustedin theform shown in Figures 7 and 8, just as it is in the form shown i-n Figure 6.- In the latter case, however, the adjustment is carried out by adjusting the cam shaft. Since the cam shaft is mounted on the frame which can be rotated, this frame is rotated up and down and by its rotation the amount of movement of the rocker arms is varied and thus the amount of downward movement of the plunger caused by the rocker arms in their motion is also varied, and thus a governing eii'ectis provided.

I claim:

l. In. an injecting system for internal combustion engines and the like the combination of a main pumping unit, .a plurality of fuel injecting pump units, ported hollow rotor valves, one connected with the high pressure side of the main pump and the series of ducts-between each injector pump and the two hollow rotor valves respectively, one duct of each set communicating with theinjector pump o n one side of the operating piston thereof and the other on the opposite side thereof, the said ducts being arranged to communicate with the roto` valves through the ports thereof as the valve is rotated, and means for, operating fthe valves in proper timed relationship.

2. The combination stated inf claim 1, whereinthe intermediate ducts between the f other with the low pressure side thereof, a

rotor valve that is connected with the high pressure side of lthe main pump areyof vlarger size than arethe intermediate ducts communicating 'with the low pressure rotor valve.

3. The combination stated in claim 1 having the pumping units arranged in a single housing in line with each other and the rotor valves `arranged upon 'opposite sides of the injector pumps on lines parallel withthe line of pumps.

4. The combination stated in claim 1 including as a further element unitary adjusting means for limiting'the movements of a plurality of the operating pistons of the respective injector pumps.

5. In an injection system for internal combustion engines and the like, a combination of a main pumping unit, aplurality of fuel injecting pump units, rotary `valves, one connected with the high pressure side of the main pump and another with the low pressure side thereof, ducts from each injector to the rotary valves, one duct leading to the injector pump, on .one side of its operating piston, and another on the opposite side, said ducts arranged to be controlled by the operation of the rotary valves, and

, means for driving the valves in timed relation.

6. In an injection system 'for internal combustion engines and the like, a combination of a main pumping unit, a plurality of fuel injecting pump umts, rotary valves, one

connected With the high pressure side of the main pump and another with the low pressure side thereof, ducts from each injector to the rotary valves, one duct leading to the injector pump, on one side of its l'operating piston, and another on the opposite side, saidducts arranged to he controlled by the operation of the rotary valves, and means for driving the valves in timed relation with each other and with the main pumping unit.

Signed at Chicago, county of Cook and State of Illinois, this 1st day of June, 1926.

PHILIP LANE SCOTT.

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