WO1982003888A1 - Adjustable pilot injection for fuel injection apparatus - Google Patents

Adjustable pilot injection for fuel injection apparatus Download PDF

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Publication number
WO1982003888A1
WO1982003888A1 PCT/US1981/000617 US8100617W WO8203888A1 WO 1982003888 A1 WO1982003888 A1 WO 1982003888A1 US 8100617 W US8100617 W US 8100617W WO 8203888 A1 WO8203888 A1 WO 8203888A1
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WIPO (PCT)
Prior art keywords
fuel
rotor
nozzle
pilot
injection system
Prior art date
Application number
PCT/US1981/000617
Other languages
French (fr)
Inventor
Alexander Goloff
Original Assignee
Alexander Goloff
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alexander Goloff filed Critical Alexander Goloff
Priority to PCT/US1981/000617 priority Critical patent/WO1982003888A1/en
Publication of WO1982003888A1 publication Critical patent/WO1982003888A1/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B7/00—Engines characterised by the fuel-air charge being ignited by compression ignition of an additional fuel
    • F02B7/02—Engines characterised by the fuel-air charge being ignited by compression ignition of an additional fuel the fuel in the charge being liquid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M43/00—Fuel-injection apparatus operating simultaneously on two or more fuels, or on a liquid fuel and another liquid, e.g. the other liquid being an anti-knock additive
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/20—Varying fuel delivery in quantity or timing
    • F02M59/36—Varying fuel delivery in quantity or timing by variably-timed valves controlling fuel passages to pumping elements or overflow passages

Definitions

  • This invention relates generally to a fuel injection apparatus for internal combustion engines and more particularly to means for adjusting the quantity of pilot fuel injected and the timing of such injection in relation to the injection of a main fuel.
  • Applicant has developed a system wherein pilot fuel of a fixed quantity is injected into a combustion chamber in a fixed-timed relationship in respect to the starting of main fuel injection therein.
  • a fixed pilot system of this type is entirely satisfactory for many fuel injection applications, provided that there is little, if any, variation of the ignition characteristics of the pilot and/or main fuel.
  • separate fuel pumps for each cylinder must be used in applications wherein the fuels are dissimilar for pilot and main injection.
  • injection may be channeled or distributed to the cylinders by a single control rotor adapted for both axial movement and angular advancement or retardation.
  • first rotor "times" the filling of a plunger pump which is located between the first and second rotors.
  • the pump is of the variable displacement type to control the amount of fuel to be delivered and the second rotor communicates the fuel to the proper cylinder.
  • the present invention is an improvement over the fuel injection apparatus discussed above in that means are provided for adjusting both the timing and quantity of injection of a first fluid, such as a pilot fuel, in relation to the injection of a second fluid, such as a main fuel.
  • a fuel injection system comprises a source of first and second fluids, fuels, nozzle means for ejecting the fluids therefrom, pump means for communicating the pressurized fluids to the nozzle means, first rotary means for controlling the pressurization of the first fluid in the pump means to start and stop ejection of the first fluid in response to continuous rotation of the first rotary means, second rotary means for controlling the pressurization of the second fluid in the pump means to start and stop ejection of the second fluid in response to continuous rotation of the second rotary means., and adjustment means for variably controlling the timing and quantity of the injection of the first fluid in relation to injection of the second fluid.
  • the adjustment means of this invention will thus: (1) provide pilot injection, if desired, by using a separate pilot fuel having superior ignition characteristics compared to the main fuel? (2) adjust timing and quantity of pilot fuel injection even during the operation of an engine; (3) provide the above desiderata while yet maintaining full control of the timing and quantity of the main injection by utilizing continuously rotating control rotors; and (4) easily adapt the fuel injection apparatus of this invention to electronic control systems, unit injectors, in-line fuel pumps, unit pumps, and various other types of pumping systems.
  • Figure 1 schematically illustrates a fuel injection system including a fuel injection apparatus embodiment of the present invention therein;
  • Figure 2 is an enlarged and partially sectioned view illustrating details of a pilot fuel injection means employed in the fuel injection apparatus;
  • Figure 3 illustrates a portion of the pilot fuel injection means;
  • Figure 4 schematically illustrates an electronic circuit for continuously rotating rotors employed in the fuel injection apparatus.
  • FIG. 1 illustrates a fuel injection system 10 including a fuel injection apparatus 11 for selectively controlling the ejection of pilot and main fuels through nozzles 12 and 13, respectively.
  • System 10 includes a first reservoir 14, containing a supply of a first fluid 15, such as a pilot fuel which may exhibit a relatively high cetane rating for quick ignition.
  • the pilot fuel is communicated to fuel injection apparatus 11 via a standard pump 16 and a conduit 17.
  • a second reservoir 18 contains a second fluid 19, such as a main fuel which may have a lower cetane rating than the pilot fuel and is communicated to fuel injection apparatus 11 via a standard pump 20 and a conduit 21.
  • conduit 21 communicates with a high pressure main fuel pump 22 having a plunger 23 reciprocally mounted therein.
  • plunger 23 is continuously reciprocated during engine operation by a lobe 24' of an engine-driven camshaft 24 to periodically communicate pressurized fuel from a pumping cavity 25 to main fuel nozzle 13, via a conduit 26.
  • Pumping cavity 25 further communicates with a .rrotary means 27, via a conduit 28, that functions to control the pressurization of fuel in pumping cavity 25 to both start and stop ejection of main fuel through injector 13 in response to continuous rotation of rotarymeans 27,
  • Rotary means 27 comprises a first rotor 29, mounted in a stationary housing 30, having a circumferential groove 31 formed thereon and interrupted by a blocking shoulder 32.
  • pumping cavity 25 is free to communicate with a second rotor 33 via conduit 28, an inlet 34, groove 31, an outlet 35, and a conduit 36.
  • Rotor 33 is mounted in a housing 37 which may form part of housing 30 and has a circumferential groove 38 formed thereon which is interrupted by a blocking shoulder 39.
  • conduit 36 is free to communicate with a drain conduit 40, via an inlet 41, groove 38, and an outlet 42.
  • cam 24 to reciprocate plunger 23 and the rotation of rotors 29 and 33 are properly sequenced in timed relationship to effect main fuel injection upon upward movement of plunger 23 while simultaneously blocking inlet 34 by blocking shoulder 32 and thereafter relieving the high pressure in the pumping cavity to stop such injection by positioning blocking shoulders 32 and 39 in their illustrated non-blocking positions whereby the pumping cavity will be vented to reservoir 18.
  • Electronic means 43 may be utilized to continuously rotate rotors 29 and 33 during engine operation.
  • the rotors may be continuously rotated by a suitable power-takeoff from the crankshaft of the engine (not shown), as is also well known in the arts relating hereto.
  • Figure 4 schematically illustrates one possible embodiment of each electronic means 43.
  • each electronic means 43 comprises a control transmitter 44 and a control transformer and servo 45.
  • Control transmitter 44 may be suitably driven by camshaft 24 ( Figure 1) at one- half engine speed (for a four-cycle engine), and through well-known.buffering networks is adapted to directly drive control transformer and servo 45 to rotate a respective rotor 29 or 33.
  • By selectively adjusting the position of a stator 46 of control transmitter 44 the starting of injection by rotor 29 can be closely controlled. This adjustment is accomplished by adjusting the timed position of blocking shoulder 32 relative to the rotational position of camshaft 24 to precisely set the time when blocking shoulder 32 begins to block inlet 34 to thus control the starting of fuel injection by pump 22.
  • Electronic means 43 associated with rotor 33, functions in a similar manner to have its control transmitter 44 also driven by camshaft 24 to directly drive control transformer and servo 45 for rotating the rotor. Adjustment of stator 46 will control the stopping of fuel injection by pump 22 in that the timed position of blocking shoulder 39 relative to blocking shoulder 32 will precisely set the timing whereat blocking shoulders 32 and 39 are opened to vent pumping cavity 25 to reservoir 18 in the manner described above.
  • the off-the-shelf type of electronic equipment utilized for supplying the above-described functions of electronic means 43 is readily available from commercial suppliers, such as Aeroflex and the Singer Instrument Company, both of the United States of America. Since the means for continuously rotating rotors 29 and 33 does not, per se, form part of this invention, further discussion thereon is deemed unnecessary for a full understanding and practicing of this invention.
  • this invention is directed to an adjustment means 47 for variably controlling or infinitely adjusting within a predetermined range, the quantity of pilot fuel injected through nozzle 12. by a rotary means 48, including an upper extension of rotor 29, and the timing of such injection in relation to the injection of main fuel through nozzle 13 by rotary means 27.
  • Rotarymeans 48 includes an annular groove 49 formed circumferentially on rotor 29 to continuously communicate pilot fuel from reservoir 14 to a high pressure pilot fuel pump 22' .
  • Fuel pump 22* functions substantially the same as fuel pump 22 to have a plunger 23 ' thereof continuously reciprocated by a second cam lobe 24 ' ' secured on camshaft 24.
  • reservoir 14 and pump 16 supply pilot fuel to a radial passage 50 which is connected to a longitudinal passage 51, both formed in the upper end of rotor 29.
  • a plug 52 is secured in sealed relationship in the upper end of passage 51 to prevent the egress of pilot fuel thereby.
  • a pair of radial branch passages 53 communicate pilot fuel from passage 51 to a circumferential groove 54, formed on an upper end of rotor 29, which is interrupted by a trapezoidally- shaped blocking shoulder 55.
  • Adjustment means 47 comprises an annular control sleeve 56 which is mounted on the upper end of rotor 29 for both axial and rotational adjustment thereon. Axial adjustment of control sleeve 56 relative to rotor 29 may be effected by a first control means 57 which may include a lever arm 58
  • OMPI pivotally mounted at 59 on the engine and a ball 60 secured on the end of the lever arm to engage an annular groove 61 formed externally on control sleeve 56.
  • first control means . 57 will function to closely and variably control the quantity of pilot fuel injected through injector 12 during engine operation, i.e., to lengthen or shorten the duration of such pilot injection.
  • a second control means 62 for selectively adjusting and variably controlling the timing of the pilot injection relative to the injection of main fuel by injector 13 may include a link 63 attached to control sleeve 56 by a ball and socket connection 64 to selectively rotate the control sleeve relative to rotor 29.
  • control means 57 and 62 may be actuated independently or simultaneously.
  • the control means may be actuated manually to place control sleeve 56 in the desired axial and rotational positions, as dictated by the characteristics of a specific fuel and previous experience with such fuel.
  • the selected adjustment of control sleeve 56 may be accomplished automatically, such as by the so-called electronic engine control (EEC).
  • EEC electronic engine control
  • pilot fuel is effected by fuel pump 22' which communicates pressurized pilot fuel to nozzle 12 via an inlet 65, groove 49, an outlet 66, and a conduit 67.
  • standard delivery or check valves are normally mounted at the inlets to conduits 26 and 67 to prevent emptying of the conduits.
  • blocking shoulder 55 will cover a spill passage 68, communicating with a drain conduit 69, in timed relationship relative to rotation of camshaft 24 and reciprocation of plunger 23'. Pilot injection is terminated when rotor 29 further rotates to uncover spill passage 68 to vent the pressurized pilot fuel via passages 51 and 53.
  • blocking shoulder 55 is preferably trapezoidally shaped and tapered in an axial direction on rotor 29 to provide an abrupt opening and closing of spill passage 68. Movement of control sleeve 56 to its uppermost position in Figure 1 would effect the longest or maximum duration of pilot injection M with the relative position of spill passage 68 being indicated at 68' on a first end 55' of the blocking shoulder defining a maximum circumferential blocking surface thereon. Upon extreme downward shifting of control sleeve 56 relative to rotor 29, as illustrated in Figure 1, a minimum duration of pilot fuel injection N will be effected with the relative positioning of spill passage 68 being indicated at 68" on a second end 55' ' of the blocking shoulder defining a minimum circumferential blocking surface thereon.
  • spill passage 68 preferably comprises a trapezoidal cross-section to aid in the abrupt starting and stopping of pilot fuel injection across duration bands M and N and all intermediate bands. Infinite adjustment of the quantity of pilot fuel injected through nozzle 12, between the illustrated maximum and minimum durations or bands M and N, is thus provided.
  • Fuel injection apparatus 11 is particularly applicable in systems providing an easily ignitable or high cetane fuel for pilot injection, followed by a less easily ignitable or relatively low cetane fuel for main injection.-
  • the primary purpose for this staged pilot-main injection sequence is to conserve petroleum-based fuels and to facilitate the use of other fuels, such as cyncrudes, shale oil, methanol, other types of alchohols, mixtures of low cetane fuels, etc.
  • rotors 29 and 33 are continuously rotated, preferably at constant speeds, to provide the sequential pilot and main fuel injections through nozzles 12 and 13, respectively.
  • Control means 57 and 62 are suitably actuated to position control sleeve 56 in its desired axial and rotational position relative to rotor 29, whereby the duration of pilot injection and the timing thereof relative to main fuel injection may be achieved, as dictated by specific fuel characteristics.
  • the positioning of blocking shoulder 55 relative to spill passage 68 will control pilot injection, whereas the sequential and timed positioning of blocking shoulders 32 and 39 will effect the starting and stopping of main fuel injection.
  • fuel injection apparatus 11 has application to systems employing in- line fuel pumps, unit pumps, unit injectors, distributor pumps, and "common rail" systems.
  • the main reason therefor is that rotors 29 and 33 only control the injection timing and quantity, whether pilot or main fuel injection, downstream of the source of pressurized fuel.
  • pumps 22 and 22' would be combined with nozzles 13 and 12, respectively, to thus provide two separate unit injectors per cylinder.
  • One of the unit injectors could carry both control rotors 29 and 33 with a short fuel conduit connecting the two injectors.
  • a single nozzle 12 or 13 could also be utilized in certain applications to effect both the pilot and main fuel injections, e.g., in Figure 1, line 26 could be connected to line 67 and nozzle 13 could be eliminated. For this to be accomplished, and for other reasons such as blowing line 26 or 67 empty when the blocking shoulders are in their non-blocking positions, delivery valves, such as the schematically illustrated standard check valves, would be required at the discharge sides of the fuel pumps.
  • control sleeve 56 can be rotated by control means 62 to coincide the pilot injection with the main injection.
  • pilot injection is thus eliminated to provide simultaneous injection or at least overlapping injection periods, preferably at two distinct locations in the cylinder.
  • separate fuels are preferably used for pilot and main injection purposes, i.e., low and high cetane fuels, it should be understood that the same fuel could be used for pilot and main injection, if so desired.
  • fuel control apparatus 11 will still allow the operator to ignite the "poorer" fuel to maintain emissions at an acceptably low level.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)

Abstract

Fuel injection apparatus employing continuously rotating rotors function to eject a fixed quantity of pilot into a cylinder in a fixed timing relationship relative to the starting of main fuel injection. Although these relationships are satisfactory when the ignition characteristics of the pilot and/or main fuels are within acceptable limits, deviation from such limits may give rise to emission and related problems. This invention is directed to overcoming the above problem by providing an adjustment mechanism (47) for infinitely adjusting the quantity of the injected pilot fuel (15) and the timing of such pilot injection in relation to the injection of main fuel (19). Rotors (29, 33) are employed for controlling the injection of both the pilot (15) and main (19) fuels.

Description

Description
Adjustable Pilot Injection for Fuel Injection Apparatus
Technical Field This invention relates generally to a fuel injection apparatus for internal combustion engines and more particularly to means for adjusting the quantity of pilot fuel injected and the timing of such injection in relation to the injection of a main fuel.
Background Art
Applicant has developed a system wherein pilot fuel of a fixed quantity is injected into a combustion chamber in a fixed-timed relationship in respect to the starting of main fuel injection therein. A fixed pilot system of this type is entirely satisfactory for many fuel injection applications, provided that there is little, if any, variation of the ignition characteristics of the pilot and/or main fuel. In addition, separate fuel pumps for each cylinder must be used in applications wherein the fuels are dissimilar for pilot and main injection.
If the same fuel is used for both pilot and main injection, only one plunger-type fuel pump is required per cylinder, as further determined by the applicant. However, in both of the above types of systems, it may prove desirable to provide means for adjusting the quantity of the pilot fuel injected into the cylinder and also the timing of such injection in relation to the injection of the main fuel, particularly where the pilot and main fuels exhibit variable burning characteristics. The prior art discloses distributor-type fuel pumps having control rotors adapted for axial movement to control the quantity of injected fuel and angular advancement or retardation relative to the engine's crankshaft to control timing in response to operation of the engine's flyweights, for example. In applications wherein a single plunger pump is utilized to feed all of the cylinders, injection may be channeled or distributed to the cylinders by a single control rotor adapted for both axial movement and angular advancement or retardation. In systems wherein two control rotors are utilized, such as disclosed in U.S. Patent No. 2,652,041 issued on September 15, 1953 to Hans . Knudsen, the first rotor "times" the filling of a plunger pump which is located between the first and second rotors. The pump is of the variable displacement type to control the amount of fuel to be delivered and the second rotor communicates the fuel to the proper cylinder. The present invention is an improvement over the fuel injection apparatus discussed above in that means are provided for adjusting both the timing and quantity of injection of a first fluid, such as a pilot fuel, in relation to the injection of a second fluid, such as a main fuel.
Disclosure of Invention
In one aspect of the present invention, a fuel injection system comprises a source of first and second fluids, fuels, nozzle means for ejecting the fluids therefrom, pump means for communicating the pressurized fluids to the nozzle means, first rotary means for controlling the pressurization of the first fluid in the pump means to start and stop ejection of the first fluid in response to continuous rotation of the first rotary means, second rotary means for controlling the pressurization of the second fluid in the pump means to start and stop ejection of the second fluid in response to continuous rotation of the second rotary means., and adjustment means for variably controlling the timing and quantity of the injection of the first fluid in relation to injection of the second fluid. The adjustment means of this invention will thus: (1) provide pilot injection, if desired, by using a separate pilot fuel having superior ignition characteristics compared to the main fuel? (2) adjust timing and quantity of pilot fuel injection even during the operation of an engine; (3) provide the above desiderata while yet maintaining full control of the timing and quantity of the main injection by utilizing continuously rotating control rotors; and (4) easily adapt the fuel injection apparatus of this invention to electronic control systems, unit injectors, in-line fuel pumps, unit pumps, and various other types of pumping systems.
Brief Description of the Drawings
Other advantages and" objects of this invention will become apparent from the following description and accompanying drawings wherein;
Figure 1 schematically illustrates a fuel injection system including a fuel injection apparatus embodiment of the present invention therein; Figure 2 is an enlarged and partially sectioned view illustrating details of a pilot fuel injection means employed in the fuel injection apparatus; Figure 3 illustrates a portion of the pilot fuel injection means; and
Figure 4 schematically illustrates an electronic circuit for continuously rotating rotors employed in the fuel injection apparatus.
Best Mode of Carrying Out the Invention
Figure 1 illustrates a fuel injection system 10 including a fuel injection apparatus 11 for selectively controlling the ejection of pilot and main fuels through nozzles 12 and 13, respectively. System 10 includes a first reservoir 14, containing a supply of a first fluid 15, such as a pilot fuel which may exhibit a relatively high cetane rating for quick ignition. The pilot fuel is communicated to fuel injection apparatus 11 via a standard pump 16 and a conduit 17. A second reservoir 18 contains a second fluid 19, such as a main fuel which may have a lower cetane rating than the pilot fuel and is communicated to fuel injection apparatus 11 via a standard pump 20 and a conduit 21.
Still referring to Figure 1, conduit 21 communicates with a high pressure main fuel pump 22 having a plunger 23 reciprocally mounted therein. As is well known in the art, plunger 23 is continuously reciprocated during engine operation by a lobe 24' of an engine-driven camshaft 24 to periodically communicate pressurized fuel from a pumping cavity 25 to main fuel nozzle 13, via a conduit 26. Pumping cavity 25 further communicates with a .rrotary means 27, via a conduit 28, that functions to control the pressurization of fuel in pumping cavity 25 to both start and stop ejection of main fuel through injector 13 in response to continuous rotation of rotarymeans 27, Rotary means 27 comprises a first rotor 29, mounted in a stationary housing 30, having a circumferential groove 31 formed thereon and interrupted by a blocking shoulder 32. In the illustrated open or non-blocking position of shoulder 32 in Figure 1, pumping cavity 25 is free to communicate with a second rotor 33 via conduit 28, an inlet 34, groove 31, an outlet 35, and a conduit 36. Rotor 33 is mounted in a housing 37 which may form part of housing 30 and has a circumferential groove 38 formed thereon which is interrupted by a blocking shoulder 39. In the illustrated open or non- blocking position of shoulder 39 in Figure 1, conduit 36 is free to communicate with a drain conduit 40, via an inlet 41, groove 38, and an outlet 42. The rotation of cam 24 to reciprocate plunger 23 and the rotation of rotors 29 and 33 are properly sequenced in timed relationship to effect main fuel injection upon upward movement of plunger 23 while simultaneously blocking inlet 34 by blocking shoulder 32 and thereafter relieving the high pressure in the pumping cavity to stop such injection by positioning blocking shoulders 32 and 39 in their illustrated non-blocking positions whereby the pumping cavity will be vented to reservoir 18.
Electronic means 43 may be utilized to continuously rotate rotors 29 and 33 during engine operation. Alternatively, the rotors may be continuously rotated by a suitable power-takeoff from the crankshaft of the engine (not shown), as is also well known in the arts relating hereto. Figure 4 schematically illustrates one possible embodiment of each electronic means 43.
IREXTJΓ As shown in Figure 4, each electronic means 43 comprises a control transmitter 44 and a control transformer and servo 45. Control transmitter 44 may be suitably driven by camshaft 24 (Figure 1) at one- half engine speed (for a four-cycle engine), and through well-known.buffering networks is adapted to directly drive control transformer and servo 45 to rotate a respective rotor 29 or 33. By selectively adjusting the position of a stator 46 of control transmitter 44, the starting of injection by rotor 29 can be closely controlled. This adjustment is accomplished by adjusting the timed position of blocking shoulder 32 relative to the rotational position of camshaft 24 to precisely set the time when blocking shoulder 32 begins to block inlet 34 to thus control the starting of fuel injection by pump 22.
Electronic means 43, associated with rotor 33, functions in a similar manner to have its control transmitter 44 also driven by camshaft 24 to directly drive control transformer and servo 45 for rotating the rotor. Adjustment of stator 46 will control the stopping of fuel injection by pump 22 in that the timed position of blocking shoulder 39 relative to blocking shoulder 32 will precisely set the timing whereat blocking shoulders 32 and 39 are opened to vent pumping cavity 25 to reservoir 18 in the manner described above. The off-the-shelf type of electronic equipment utilized for supplying the above-described functions of electronic means 43 is readily available from commercial suppliers, such as Aeroflex and the Singer Instrument Company, both of the United States of America. Since the means for continuously rotating rotors 29 and 33 does not, per se, form part of this invention, further discussion thereon is deemed unnecessary for a full understanding and practicing of this invention.
Referring to Figures 1-3, this invention is directed to an adjustment means 47 for variably controlling or infinitely adjusting within a predetermined range, the quantity of pilot fuel injected through nozzle 12. by a rotary means 48, including an upper extension of rotor 29, and the timing of such injection in relation to the injection of main fuel through nozzle 13 by rotary means 27. Rotarymeans 48 includes an annular groove 49 formed circumferentially on rotor 29 to continuously communicate pilot fuel from reservoir 14 to a high pressure pilot fuel pump 22' . Fuel pump 22* functions substantially the same as fuel pump 22 to have a plunger 23 ' thereof continuously reciprocated by a second cam lobe 24 ' ' secured on camshaft 24.
In addition to supplying pilot fuel to pump 22', reservoir 14 and pump 16 supply pilot fuel to a radial passage 50 which is connected to a longitudinal passage 51, both formed in the upper end of rotor 29. A plug 52 is secured in sealed relationship in the upper end of passage 51 to prevent the egress of pilot fuel thereby. A pair of radial branch passages 53 communicate pilot fuel from passage 51 to a circumferential groove 54, formed on an upper end of rotor 29, which is interrupted by a trapezoidally- shaped blocking shoulder 55.
Adjustment means 47 comprises an annular control sleeve 56 which is mounted on the upper end of rotor 29 for both axial and rotational adjustment thereon. Axial adjustment of control sleeve 56 relative to rotor 29 may be effected by a first control means 57 which may include a lever arm 58
OMPI pivotally mounted at 59 on the engine and a ball 60 secured on the end of the lever arm to engage an annular groove 61 formed externally on control sleeve 56. As will be more fully explained hereinafter, axial adjustment of control sleeve 56 on rotor 29 by first control means.57 will function to closely and variably control the quantity of pilot fuel injected through injector 12 during engine operation, i.e., to lengthen or shorten the duration of such pilot injection.
A second control means 62 for selectively adjusting and variably controlling the timing of the pilot injection relative to the injection of main fuel by injector 13 may include a link 63 attached to control sleeve 56 by a ball and socket connection 64 to selectively rotate the control sleeve relative to rotor 29. It should be understood, of course, that control means 57 and 62 may be actuated independently or simultaneously. The control means may be actuated manually to place control sleeve 56 in the desired axial and rotational positions, as dictated by the characteristics of a specific fuel and previous experience with such fuel. Alternatively, the selected adjustment of control sleeve 56 may be accomplished automatically, such as by the so-called electronic engine control (EEC). Electronic engine control systems of this type involve sophisticated electronic control apparatus and are not the subject of this invention. Injection of pilot fuel is effected by fuel pump 22' which communicates pressurized pilot fuel to nozzle 12 via an inlet 65, groove 49, an outlet 66, and a conduit 67. As schematically illustrated in Figure 1, standard delivery or check valves are normally mounted at the inlets to conduits 26 and 67 to prevent emptying of the conduits. During pilot injection, blocking shoulder 55 will cover a spill passage 68, communicating with a drain conduit 69, in timed relationship relative to rotation of camshaft 24 and reciprocation of plunger 23'. Pilot injection is terminated when rotor 29 further rotates to uncover spill passage 68 to vent the pressurized pilot fuel via passages 51 and 53. Referring to Figure 3, blocking shoulder 55 is preferably trapezoidally shaped and tapered in an axial direction on rotor 29 to provide an abrupt opening and closing of spill passage 68. Movement of control sleeve 56 to its uppermost position in Figure 1 would effect the longest or maximum duration of pilot injection M with the relative position of spill passage 68 being indicated at 68' on a first end 55' of the blocking shoulder defining a maximum circumferential blocking surface thereon. Upon extreme downward shifting of control sleeve 56 relative to rotor 29, as illustrated in Figure 1, a minimum duration of pilot fuel injection N will be effected with the relative positioning of spill passage 68 being indicated at 68" on a second end 55' ' of the blocking shoulder defining a minimum circumferential blocking surface thereon.
It should be further noted in Figure 3 that spill passage 68 preferably comprises a trapezoidal cross-section to aid in the abrupt starting and stopping of pilot fuel injection across duration bands M and N and all intermediate bands. Infinite adjustment of the quantity of pilot fuel injected through nozzle 12, between the illustrated maximum and minimum durations or bands M and N, is thus provided. Industrial Applicability
Fuel injection apparatus 11 is particularly applicable in systems providing an easily ignitable or high cetane fuel for pilot injection, followed by a less easily ignitable or relatively low cetane fuel for main injection.- The primary purpose for this staged pilot-main injection sequence is to conserve petroleum-based fuels and to facilitate the use of other fuels, such as cyncrudes, shale oil, methanol, other types of alchohols, mixtures of low cetane fuels, etc.
In operation, rotors 29 and 33 are continuously rotated, preferably at constant speeds, to provide the sequential pilot and main fuel injections through nozzles 12 and 13, respectively. Control means 57 and 62 are suitably actuated to position control sleeve 56 in its desired axial and rotational position relative to rotor 29, whereby the duration of pilot injection and the timing thereof relative to main fuel injection may be achieved, as dictated by specific fuel characteristics. As discussed above, the positioning of blocking shoulder 55 relative to spill passage 68 will control pilot injection, whereas the sequential and timed positioning of blocking shoulders 32 and 39 will effect the starting and stopping of main fuel injection.
It should be understood that fuel injection apparatus 11 has application to systems employing in- line fuel pumps, unit pumps, unit injectors, distributor pumps, and "common rail" systems. The main reason therefor is that rotors 29 and 33 only control the injection timing and quantity, whether pilot or main fuel injection, downstream of the source of pressurized fuel. In application to unit injectors, pumps 22 and 22' would be combined with nozzles 13 and 12, respectively, to thus provide two separate unit injectors per cylinder. One of the unit injectors could carry both control rotors 29 and 33 with a short fuel conduit connecting the two injectors. A single nozzle 12 or 13 could also be utilized in certain applications to effect both the pilot and main fuel injections, e.g., in Figure 1, line 26 could be connected to line 67 and nozzle 13 could be eliminated. For this to be accomplished, and for other reasons such as blowing line 26 or 67 empty when the blocking shoulders are in their non-blocking positions, delivery valves, such as the schematically illustrated standard check valves, would be required at the discharge sides of the fuel pumps.
It should be further understood that control sleeve 56 can be rotated by control means 62 to coincide the pilot injection with the main injection. In one sense, "pilot injection" is thus eliminated to provide simultaneous injection or at least overlapping injection periods, preferably at two distinct locations in the cylinder. Although separate fuels are preferably used for pilot and main injection purposes, i.e., low and high cetane fuels, it should be understood that the same fuel could be used for pilot and main injection, if so desired. In systems wherein any time delay between the pilot and main injections proves objectionable from the emissions standpoint, fuel control apparatus 11 will still allow the operator to ignite the "poorer" fuel to maintain emissions at an acceptably low level.
Other aspects, objects, and advantages of this invention can be obtained from a study of the drawings, the disclosure, and the appended claims.
ZE

Claims

Claims
1. A fuel injection system (10) comprising a source (14,18) of first (15) and second
(19) separate fluids, nozzle means (12,13) for ejecting the first (15) and second (19) fluids therefrom, pump means (22,22') for communicating the pressurized first (15) and second (19) fluids to said nozzle means (12,13), first rotary means (48) for controlling the pressurization of the first fluid (15) in said pump means (22') to start and stop ejection of the first fluid (15) through said nozzle means (12) in response to continuous rotation of said first rotary means (48), second rotary means (27) for controlling the pressurization of the second fluid (19) in said pump means (22) to start and stop ejection of the second fluid (19) through said nozzle means (13) in response to continuous rotation of said second rotary means (27), and adjustment means (47) for variably controlling the timing and the quantity of the injection of the first fluid (15) from said nozzle means (12) in relation to the injection of the second fluid (19) from said nozzle means (13).
2. The fuel injection system (10) of claim 1 wherein said first rotary means (48) includes a rotor (29) having a blocking shoulder (55) defined thereon and wherein said adjustment means includes a control sleeve (56) mounted for axial and rotational movements on said rotor (29) and disposed circumferentially about said blocking shoulder (55).
3. The fuel injection system (10) of claim
2 further including a circumferential groove (54) formed on said rotor (29) and interrupted by said blocking shoulder (55) and a spill passage (68) formed in said control sleeve (56) and communicating said first fluid (15) with said groove (55).
4. The fuel injection system (10) of claim
3 wherein said blocking shoulder (55) is tapered in an axial direction on said rotor (29) from a first end (55') defining a maximum circumferential blocking surface to a second end (55, f) defining a minimum circumferential blocking surface.
5. The fuel injection system (10) of claim
4 wherein said blocking shoulder (55) is trapezoidally shaped.
6. The fuel injection system (10) of claim
2 wherein said adjustment means (47) further includes first control means (57) for moving said control sleeve (56) axially relative to said rotor (29) and second control means (62) for rotating said control sleeve (56) relative to said rotor (29).
7. The fuel injection system (10) of claim
3 wherein said source (14,18) includes a first source (14) of said first fluid and a separate second source (18) of said second fluid, said nozzle means (12,13) includes a first nozzle (12) and a separate second nozzle (13), and said pump means (22, 22') includes a first pump (22') and a separate second pump (22).
8. The fuel injection system (10) of claim
7 wherein said first fuel pump (22') is connected between said first source (14) and said rotor (29) and said first nozzle (12) is connected to said rotor (29) downstream thereof, and further including an annular groove (49) defined on said rotor and having an inlet (65) connected to said first fuel pump (22') and an outlet (66) connected to said first nozzle (12) and passage means (50,51,53) for communicating said first fluid (15) from said annular groove (49) to said circumferential groove (54) and to said spill passage (68) when said blocking shoulder (55) is in a rotative, non-blocking position relative to said spill passage (68).
9. The fuel injection system (10) of claim
8 wherein said second pump (22) is interconnected between said rotor (29) and said second nozzle (13) and is further connected to said second source (18).
10. The fuel injection system (10) of claim 9 wherein said second rotary means (27) includes first blocking shoulder means (32) on said rotor (29) for starting ejection of said second fluid (19) through said second nozzle in response to said second pump (22) and another rotor (33) interconnected between said second source (18) and said first blocking shoulder means (32) and having second blocking shoulder means (39) for stopping injection of said second fluid (19).
11. The fuel injection system (10) of claim 10 further including means (43) for continuously rotating each of said first-mentioned rotor (29) and said another rotor (33).
12. A fuel injection system (10) comprising a source of pilot fuel (14), a pilot fuel pump (22*) connected to said source of pilot fuel (14), a pilot fuel nozzle (12), first rotary means (48) for controlling pressurization of pilot fuel (15) in said pilot fuel pump (22') to start and stop ejection of pilot fuel (15) through said pilot fuel nozzle (12) in response to rotation of said first rotary means (48), a source of main fuel (18), a main fuel pump (22) connected to said source of main fuel (18), a main fuel nozzle (13), second rotary means (27) for controlling pressurization of main fuel (19) in said main fuel pump (22) to start and stop ejection of main fuel (19) through said main fuel nozzle (13) in response to rotation of said second rotary means (27), and adjustment means (47) for infinitely adjusting, within a predetermined range, the quantity of the pilot fuel (15) injected through said pilot fuel nozzle (12) under control of said first rotary means (48) and the timing of such pilot injection in relation to the injection of main fuel (19) through said main fuel nozzle (13) under control of said second rotary means (27) .
13. The fuel injection system (10) of claim 11 wherein said first rotary means (48) includes a rotor (29) having a blocking shoulder (55) defined thereon and wherein said adjustment means includes a control sleeve (56) mounted for axial and rotational movements on said rotor (29) and disposed circumferentially about said blocking shoulder (55).
14.- The fuel injection system (10) of claim
13 further including a circumferential groove (54) formed on said rotor (29) and interrupted by said blocking shoulder (55) and a spill passage (68) formed in said control sleeve (56) and communicating said source of pilot fuel (14) with said groove (54).
15. The fuel injection system (10) of claim
14 wherein said blocking shoulder (55) is tapered in an axial direction on said rotor (29) from a first end (55') defining a maximum circumferential blocking surface to a second end (55'') defining a minimum circumferential blocking surface.
16. The fuel injection system (10) of claim
15 wherein said blocking shoulder (55) is trapezoidally shaped.
17. The fuel injection system (10) of claim
13 wherein said adjustment means (47) further includes first control means (57) for moving said control sleeve (56) axially relative to said rotor (29) and second control means (62) for rotating said control sleeve (56) relative to said rotor (29).
18. The fuel injection system (10) of claim
14 wherein said pilot fuel pump (22') is connected between said source of pilot fuel (14) and said rotor (29) and said pilot fuel nozzle (12) is connected to said rotor (29) downstream thereof, and further including an annular groove (49) defined on said rotor and having an inlet (65) connected to said pilot fuel pump (22') and an outlet (66) connected to said pilot fuel nozzle (12), and passage means (50,51,53) for (Clai 18 - continued)
communicating pilot fuel (15) from said annular groove (49) to said circumferential groove (54) and to said spill passage (68) when said blocking shoulder (55) is in a. rotative, non-blocking position relative to said spill passage (68).
19. The fuel injection system (10) of claim
18 wherein said main fuel pump (22) is interconnected between said rotor (29) and said main fuel nozzle (13) and is further connected to said main fuel source (18).
20. The fuel injection system (10) of claim
19 wherein said second rotary means (27) includes first blocking shoulder means (32) on said rotor (29) for starting ejection of main fuel (19) through said main fuel nozzle (13) in response to said main fuel pump (22) and another rotor (33) interconnected between said main fuel source (18) and said first blocking shoulder means (32) and having second blocking shoulder means (39) for stopping said main fuel injection.
21. The fuel injection system (10) of claim
20 further including means (43) for continuously rotating each of said first-mentioned rotor (29) and said another rotor (33).
PCT/US1981/000617 1981-05-04 1981-05-04 Adjustable pilot injection for fuel injection apparatus WO1982003888A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US1981/000617 WO1982003888A1 (en) 1981-05-04 1981-05-04 Adjustable pilot injection for fuel injection apparatus

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
WOUS81/00617810504 1981-05-04
PCT/US1981/000617 WO1982003888A1 (en) 1981-05-04 1981-05-04 Adjustable pilot injection for fuel injection apparatus

Publications (1)

Publication Number Publication Date
WO1982003888A1 true WO1982003888A1 (en) 1982-11-11

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PCT/US1981/000617 WO1982003888A1 (en) 1981-05-04 1981-05-04 Adjustable pilot injection for fuel injection apparatus

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1014518C2 (en) * 2000-02-29 2001-08-30 Technoscan Engineering B V Device, fuel injection system and method for metering fuel.

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2319858A (en) * 1941-02-24 1943-05-25 Harlow B Grow Method and means for controlling combustion engines
US2356627A (en) * 1940-06-27 1944-08-22 George A Rubissow Interruption injection pump
US2692587A (en) * 1952-06-23 1954-10-26 Texas Co Internal-combustion engine
US3575146A (en) * 1969-02-06 1971-04-20 Physics Int Co Fuel injection system for an internal combustion engine
US3791361A (en) * 1971-09-09 1974-02-12 Bosch Gmbh Robert Rpm regulator for a fuel injection pump serving an internal combustion engine
US4132201A (en) * 1973-10-03 1979-01-02 Eaton Corporation Metering valve for fuel injection
US4211520A (en) * 1978-01-20 1980-07-08 Caterpillar Tractor Co. Timing control for sleeve metering fuel system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2356627A (en) * 1940-06-27 1944-08-22 George A Rubissow Interruption injection pump
US2319858A (en) * 1941-02-24 1943-05-25 Harlow B Grow Method and means for controlling combustion engines
US2692587A (en) * 1952-06-23 1954-10-26 Texas Co Internal-combustion engine
US3575146A (en) * 1969-02-06 1971-04-20 Physics Int Co Fuel injection system for an internal combustion engine
US3791361A (en) * 1971-09-09 1974-02-12 Bosch Gmbh Robert Rpm regulator for a fuel injection pump serving an internal combustion engine
US4132201A (en) * 1973-10-03 1979-01-02 Eaton Corporation Metering valve for fuel injection
US4211520A (en) * 1978-01-20 1980-07-08 Caterpillar Tractor Co. Timing control for sleeve metering fuel system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1014518C2 (en) * 2000-02-29 2001-08-30 Technoscan Engineering B V Device, fuel injection system and method for metering fuel.
WO2001071180A1 (en) * 2000-02-29 2001-09-27 Technoscan Engineering B.V. Apparatus, fuel injection system, and method for metering fuel

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