US3539159A - Flow rate-responsive fuel mixture control device - Google Patents

Flow rate-responsive fuel mixture control device Download PDF

Info

Publication number
US3539159A
US3539159A US759091A US75909168A US3539159A US 3539159 A US3539159 A US 3539159A US 759091 A US759091 A US 759091A US 75909168 A US75909168 A US 75909168A US 3539159 A US3539159 A US 3539159A
Authority
US
United States
Prior art keywords
suction tube
pressure
fuel
cylinder
control member
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
US759091A
Other languages
English (en)
Inventor
Dieter Handtmann
Gerhard Stumpp
Konrad Eckert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Application granted granted Critical
Publication of US3539159A publication Critical patent/US3539159A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • F02M69/00—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel
    • F02M69/16—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors
    • F02M69/18—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors the means being metering valves throttling fuel passages to injectors or by-pass valves throttling overflow passages, the metering valves being actuated by a device responsive to the engine working parameters, e.g. engine load, speed, temperature or quantity of air
    • F02M69/24—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors the means being metering valves throttling fuel passages to injectors or by-pass valves throttling overflow passages, the metering valves being actuated by a device responsive to the engine working parameters, e.g. engine load, speed, temperature or quantity of air the device comprising a member for transmitting the movement of the air throttle valve actuated by the operator to the valves controlling fuel passages
    • 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
    • F02M69/00—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel
    • F02M69/16—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors
    • F02M69/18—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors the means being metering valves throttling fuel passages to injectors or by-pass valves throttling overflow passages, the metering valves being actuated by a device responsive to the engine working parameters, e.g. engine load, speed, temperature or quantity of air
    • F02M69/22—Low-pressure fuel-injection apparatus ; Apparatus with both continuous and intermittent injection; Apparatus injecting different types of fuel characterised by means for metering continuous fuel flow to injectors or means for varying fuel pressure upstream of continuously or intermittently operated injectors the means being metering valves throttling fuel passages to injectors or by-pass valves throttling overflow passages, the metering valves being actuated by a device responsive to the engine working parameters, e.g. engine load, speed, temperature or quantity of air the device comprising a member movably mounted in the air intake conduit and displaced according to the quantity of air admitted to the engine

Definitions

  • Greigg ABSTRACT In a fuel injection system the metering of the fuel is controlled by a three-dimensional cam which is angu- [54] FLOW RATE'RESPONSWE FUEL MIXTURE larly displaced in unison with the arbitrary setting of a but- CONTROL DEVICE terfly valve regulating the airflow and is linearly displaced by a 13 claimssnmwingmgs linearly movable element of a pressure-responsive control [52] 0.8. CI 261/50, member. The said element is arranged in the air suction tube 261/51 of the fuel injection system and is caused to be linearly shifted [51] Int.
  • the invention relates to fuel injection systems for internal combustion engines, particularly for automotive vehicles, operating onindependently ignited fuel, wherein the air supply is controlled by the arbitrary actuation of a throttle valve disposed in the air suction tube.
  • the butterfly valve is, as known, set according to the required power output and it is the function of a control device to meter the fuel so that always the best mixture ratio (fuel/air ratio) is obtained.
  • a pressure-responsive control member which automatically controls the effective cross-sectional area of an adjustable flow passage in the suction tube; said passage is arranged upstream of the throttle valve and serves, at the same time, to control the effective crosssectional area of a fuel metering nozzle functioning as an adjustable throttle; and b. by means of a pressure control device which maintains at a constant value the fuel pressure difference under constant rpm. and load conditions at the metering nozzle, but which, however, at the same time corrects this pressure difference according to the changes in air pressure in the suction tube portion between the pressure-responsive control member and the throttle valve.
  • Such a fuel injection system has the disadvantage that the fitting of the fuel-air curve to the engine characteristic is not point by point, but, because of the aforenoted pressure control means, follows in such-a manner that the metered fuel quantity is at its optimal value at some levels of operation, but in wide operating ranges does not correspond satisfactorily to the required quantity.
  • a device in which a second throttle member controls a pneumatic servomotor with which there is associated a fuel metering valve 'which, in turn, determines the fuel/air ratio as a function of the pressure prevailing in the suction tube between the throttle valve and i the second throttle member.
  • the second throttle member is disposed in the suction tube upstream of the first throttle member (throttle valve) and is actuated in an opening direction by means of the low pressure prevailing between the throttle members and the pressure prevailing before the second throttle member.
  • a device of the aforenoted structure is disclosed in German Pat. No. 1,l9l,l77. The previously discussed disadvantage also applies to this device.
  • German Pat. No. 896,867 describes a mixture control device wherein a three-dimensional cam attached to the adjusting rod of the fuel pump is displaceable as a function of the pressure in the suction tube downstream of the throttle member and dependent of the position thereof.
  • the invention is based on the recognition that at each operating level of the internal combustion engine the fuel quantity, depending upon requirements, has to be very accurately metered. v I
  • the air streaming in an unmixed condition in the suction tube, flows past a control member which is at least partially disposed and displaceably held within the suction tube and is exposed to both the total and the static pressure prevailing in the suction tube.
  • the control member which is thus exposed the cross-sectional area of a flow passage in the suction tube dependent upon the changes in the rate of the airflow.
  • the position of the control member is thus a measure for the rate of airflow; the fuel quantity is metered continuously and under constant pressure gradient by means of the pressure-responsive control member.
  • the pressure-responsive control member which is at least partially disposed in the suction tube, there is connected in a manner known per se, a long itudinally displaceable three-dimensional camwhich is, in addition, rotatable through an angle dependent upon the desired engine output which, together with the rate of airflow, described the full performance characteristic of the internal combustion engine.
  • the said cam may be rotated as a function of the pressure in the suction tube downstream of the throttle member and the pressure-responsive control member.
  • the said cam is turned dependent upon the position of the throttle member,
  • the cam is operatively connected to a follower pin which, in turn, is associated with a fuel metering device.
  • FIG. 4 is a partial view in section taken along line lV-IV of FIG. 3;
  • FIG. 5 is an axial sectional view of a third embodiment of the invention. I
  • the fuel withdrawn from a tank 4 through a filter 5 by means of a pump 6, flows past a return conduit 7 provided with a relief valve 8 and is introduced under constant pressure into a fuel metering device 9 shown only schematically.
  • a fuel line 10 leads to one or several nozzles 11 from which the fuel is injected into the suction tube preferably shortly before the cylinder or cylinders of the internal combustion engine.
  • the pressure-responsive control member 2 comprises a stepped piston 12, the terminal portion 12a of which extends into the suction tube 1.
  • Piston 12 which is movably held in a housing 13 secured to the suction tube 1 externally thereof, is rotatable about its own axis and is axially slidable normal to the axis of the suction tube 1.
  • the piston 12 and the housing 13 define chambers 14 and 15.
  • the chamber 14 communicates with the suction tube 1 upstream of the control member 2 by means of a tube 14a, the open and flared'end portion of which is directed against the airflow.
  • the total air pressure prevails, to which there is exposed an annular shoulder 12]; of piston 12.
  • the chamber 15 communicates with the suction tube 1 by means of a port 15a that extends coaxially with piston 12 normal to the airflow in suction tube 1 and ends on the terminal face 12a of piston 12. Communication between port 15a and chamber 15 is established by means of openings 15a provided in port 15a.
  • the pressure in chamber 15 is identical to the static pressure prevailing in the passage 16 of the suction tube 1.
  • the pressure in chamber 15 is applied to the internal annular surfaces 12c, 12c and 12c" of the piston 12.
  • a weak compression spring 17 Coaxially with the piston 12 there is arranged a weak compression spring 17, one end of which engages an internal wall of housing 13, while the other end of which rests against an annular inner surface 120' of piston 12.
  • a push rod 19 fixedly secured at one end to piston 12 and including the aforeclescribed port 15a carries at its end remote from the piston a three-dimensional cam 20 which is contacted by a follower pin 9a associated with the fuel metering device 9.
  • Cam 20 has a camming face both in an axial and in a circumferential direction so that follower pin 9a may be displaced due to either a linear displacement or a rotation (or both) of cam 20.
  • the push rod 19 is connected by means of a lever and linkage assembly 21, 21a and 21b with the shaft 3a to which there is secured the butterfly valve 3 and which may be rotated at will by means of a lever arm 22.
  • the pressure-responsive control member generally indicated at 2' comprises a hollow cylinder 24 disposed coaxially within a two-part suction tube 1'.
  • the upstream end of thecylinder 24 is closed by means of a cap 24a of a streamlined configuration.
  • This upstream portion of the cylinder 24 extends into a funnel-shaped section la of the suction tube 1;
  • the cylinder 24 is axially slidably and rotatably held on a guide tube 26 closed off at its downstream end by means of a plug 25.
  • the guide tube 26 is fixedly mounted within suction tube 1 coaxially therewith by pressfitting it into a sleeve 27 affixed to the internal wall of suction tube 1 by means of radial webs 27a.
  • the hollow cylinder 24 has an axial bore 28 slidably surrounding, with a snug fit, the guide tube 26 and a larger axial bore 280 which is slidably engaged in a snug fit by a collar 29 keyed to the guide tube 26.
  • the extent of axial displacement of the hollow cylinder 24 is limited on the one hand by the terminal face 29a of the collar 29 and on the other hand by the terminal face 27b of the sleeve 27.
  • the external surface of the upstream portion of cylinder 24 and the funnel-shaped internal wall of suction tube portion 1a defines an airflow passage 30. If the hollow cylinder 24 is in its upstream extreme position (shown in dotted lines in H6. 3) in the funnel-shaped suction tube portion la, the cross-sectional area of the air passage 30 is the smallest. lf, on the other hand, the hollow cylinder 24 is in its downstream extreme position (as shown in solid lines in FIG. 3), the cross-sectional area of the air passage 30 is at its maximum.
  • the wall of the cylinder 24 is provided at its upstream end (where, at any position of cylinder 24, the cross-sectional area of the flow passage 30 is the smallest) with openings 31 which establish communication between the suction tube and the inside of the cylinder, thus ensuring that the static pressure of the airflow in flow passage 30 also prevails in the inside of the cylinder 24.
  • the static pressure within the cylinder 24 exerts a force on the inner face of the cap 24a, while the outer face thereof is exposed to the total pressure of the airflow.
  • a weak compression spring 32 In the guide tube 26 there is disposed a weak compression spring 32, one end of which is seated against the plug 25 fixedly inserted into the guide tube 26, and the other end of which engages a spring seat disc 33 secured to the cylinder 24 by means of a snap ring 34.
  • the spring 32 together with the static pressure, tends to move the cylinder 24 against the downstream directed force of the total air pressure.
  • Bore 28, guide tube 26 and terminal face 29a define a dashpot chamber 281) provided with a bleeding orifice 35. This arrangement ensures that axial oscillating motions of the cylinder 24 are strongly dampened.
  • One portion of the outer wall of the cylinder 24 is formed as a three-dimensional cam 36 which is in contact with the follower pin 9a associated with the fuel metering device 9.
  • the cylinder 24 is provided with a longitudinal groove 37 into which extends the carrier pin 38a of a lever 38 secured to a shaft 39 which, in turn, is rotatably held in the suction tube 1'.
  • the shaft 39 is secured to a lever 40 which is connected to the throttle valve 3 by means of a link 41 jointed to a lever 43 which, in turn, is fixedly secured to throttle valve shaft 42.
  • the butterfly valve 3 is I disposed upstream of the pressure-responsive control member
  • the position of the butterfly valve 3 in suction tube 1 depicted in FIG. 3 is more clearly shown in PK ⁇ . 4.
  • the butterfly valve 3' is disposed in a narrow suction tube section lb" of the two-part suction tube 1" downstream of the pressure-responsive control member generally indicated at 2".
  • a sleeve 44 which carries a three-dimensional cam 36 contacted by a follower pin 9a and a longitudinal groove 37 into which extends a carrier pin 38a of the lever 38.
  • the hollow cylinder 24 has an axial bore 28 slidably surrounding, with a snug fit, the guide tube 26' and a larger axial bore 28a which is slidably engaged in a snug fit by a collar 29' keyed to the guide tube 26.
  • the terminal face 29a of collar 29' serves as an abutment face.
  • the guide tube 26' is closed at collar 29 by a stud 45.
  • a tension spring 32' one end of, which is attached to the end wall of stud 45 while its other end is hooked to a transversal pin 46 fixedly secured at both ends to the cylinder 24 and extending through longitudinal slots 47 of the guide tube 26.
  • the length of the slots 47 provided in the guide tube 26 at diametrically opposed locations determines the extent of possible displacement of the cylinder '24.
  • FIG. 5 the structure and arrangement of the embodiment shown in FIG. 5 is generally similar to the embodiment described earlier and illustrated in FIG. 3.
  • the coaxial arrangement of the pressure-responsive control member in the suction tube in accordance with the second (FIG. 3) and third (FIG. 5) embodiment has the advantage that the entire upstream terminal face (the external surface of cap 24a of the linearly displaceable element (cylinder 24, 24') is exposed to the total pressure of airflow; the dimensions of the control member are smaller and, consequently, the forces due to inertia are also reduced. Further, by virtue .of the streamlined structure, the eddy losses are very small which results in a higher efficiency of the engine. Further, in a coaxial arrangement.
  • the pressurecomponents normal to the axis-of the pressure-responsive control member are compensated resulting in reduced frictional forces. Also, by disposing the pressureresponsive control member within the suction tube, longer air tubes and conduits which have a delaying effect, may be omitted.
  • the linear setting of the pressure-responsive control member 2, 2', 2" is determined by the dynamic pressure (total pressure less static pressure), the variation of which is an accurate measure of the change in the flow rate.
  • the linear displacement of cam 20, 36 is a function of the rate of airflow, while the angular displacement thereof is, due to an interconnectinglinkage assembly, effected in unison with the arbitrary setting of butterfly valve 3.
  • the fuel is metered by means of follower pin 9a as a function of two variables: the rate of airflow and the position of the butterfly valve.
  • the advantages achieved by the invention reside particularly in the fact that by virtue of combining the pressureresponsive control member with a three-dimensional cam adjusted to the engine characteristic, the fuel may be metered in a very accurate manner so that even in the various ranges of operation (full load, or partial load) a desired mixture ratio (rich or lean) may be set.
  • the'pressure-responsive control member may be arranged either upstream or downstream of the butterfly valve.
  • the latter arrangement is preferred, since it has the advantage that an exact metering of the fuel is possible even during the transitional period before the engine is being driven by the car and further when the engine is driven by the car, even a stoppage of fuel is possible.
  • a larger portion of the cam face is affected which is important to ensure an accuracy in the metering.
  • the suction tube does not have to be narrowed downstream of the pressure-responsive control member as in the embodiment shown in FIG. 5.
  • a fuel, injection system including a suction pipe provided with a throttle valve for the arbitrary variation of the flow of air to control the fuel-air mixture to be injected for combustion particularly in externally ignited internal combustion engines, a pressure-responsive control member associated with said suction tube and exposed to said flow of air therein, a fuel metering device responsive to both said control member and said arbitrary variation of said throttle valve, the
  • said slidable member is hollow and includes at least one port establishingcommunication between said flow passage and the inside of said slidable element to cause the static pressure in said flow passage to prevail also in the inside of saidslidable element.
  • said slidable element is a piston disposed in a housing externally of said suction tube and extending thereinto linearly displaceably normal to the airflow, one side of said piston is exposed in said housing to said static pressure, the other side of said piston is exposed in said housing to said total pressure.
  • said means responsive to said arbitrary variation of the flow of air includes a linkage mechanism interconnecting said throttle valve and said hollow cylinder to rotate the latter as said throttle valve is arbitrarily moved.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
  • Fuel-Injection Apparatus (AREA)
US759091A 1967-09-20 1968-09-11 Flow rate-responsive fuel mixture control device Expired - Lifetime US3539159A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE1576287 1967-09-20

Publications (1)

Publication Number Publication Date
US3539159A true US3539159A (en) 1970-11-10

Family

ID=5678822

Family Applications (1)

Application Number Title Priority Date Filing Date
US759091A Expired - Lifetime US3539159A (en) 1967-09-20 1968-09-11 Flow rate-responsive fuel mixture control device

Country Status (5)

Country Link
US (1) US3539159A (de)
AT (1) AT288087B (de)
FR (1) FR1577679A (de)
GB (1) GB1237734A (de)
SE (1) SE332543B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3680535A (en) * 1969-12-01 1972-08-01 Bosch Gmbh Robert Fuel injection system for combustion engines
US3724822A (en) * 1969-10-06 1973-04-03 Nissan Motor Intake air control device for internal combustion engine of fuel injection type
US3929114A (en) * 1973-08-13 1975-12-30 Vergaser Gmbh & Co Kommanditge Fuel injector arrangement for compressive mixture internal combustion engines
US3930478A (en) * 1972-09-15 1976-01-06 Robert Bosch G.M.B.H. System for the detoxication of exhaust gases
US4739650A (en) * 1985-11-19 1988-04-26 Nippondenso Co., Ltd. Gas flow measuring apparatus

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1420441A (en) * 1972-03-03 1976-01-07 Gkn Transmissions Ltd Fuel injection apparatus for internal combustion engines
SE387410B (sv) * 1974-11-25 1976-09-06 Clean Air Co Anordning for insprutningsforgasare

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3724822A (en) * 1969-10-06 1973-04-03 Nissan Motor Intake air control device for internal combustion engine of fuel injection type
US3680535A (en) * 1969-12-01 1972-08-01 Bosch Gmbh Robert Fuel injection system for combustion engines
US3930478A (en) * 1972-09-15 1976-01-06 Robert Bosch G.M.B.H. System for the detoxication of exhaust gases
US3929114A (en) * 1973-08-13 1975-12-30 Vergaser Gmbh & Co Kommanditge Fuel injector arrangement for compressive mixture internal combustion engines
US4739650A (en) * 1985-11-19 1988-04-26 Nippondenso Co., Ltd. Gas flow measuring apparatus

Also Published As

Publication number Publication date
GB1237734A (en) 1971-06-30
AT288087B (de) 1971-02-25
FR1577679A (de) 1969-08-08
SE332543B (de) 1971-02-08

Similar Documents

Publication Publication Date Title
US3680535A (en) Fuel injection system for combustion engines
US3730155A (en) Fuel injection apparatus for spark plug-ignited internal combustion engines
US3983849A (en) Fuel injection system
JPH0517396B2 (de)
US3613650A (en) Fuel injection system for internal combustion engines
JPS6111469Y2 (de)
US3539159A (en) Flow rate-responsive fuel mixture control device
US3739758A (en) Regulator mechanism for fuel injection apparatus
US4090487A (en) Fuel injection system
JPS5844865B2 (ja) ネンリヨウフンシヤソウチ
US3894523A (en) Fuel supply system
US4064843A (en) Fuel metering and injection system for internal combustion engines
US4108117A (en) Fuel metering system
US4099505A (en) Fuel injection system
US4196708A (en) Engine systems
US4134379A (en) Fuel injection system
US3896778A (en) Apparatus in a combustion engine including a device for continually measuring and individually distributing to a plurality of fuel injection valves the amounts of fuel appropriate to the amounts of combustion air
US3713430A (en) Fuel injection system
US3132191A (en) Fuel injection device
GB2109589A (en) Fuel injection pump for internal-combustion engines
CA1132416A (en) Air-fuel ratio controller
US4108128A (en) Fuel supply system for internal combustion engines
US4200074A (en) Fuel injection system for an internal combustion engine
US3951120A (en) Diaphragm-controlled pressure control valve assembly
US4090486A (en) Fuel injection system