US3726261A

US3726261A - Acceleration enrichment signalling means for electronic fuel systems

Info

Publication number: US3726261A
Application number: US00109278A
Authority: US
Inventors: R Sauer
Original assignee: Bendix Corp
Current assignee: Bendix Corp; Siemens Automotive LP
Priority date: 1971-01-25
Filing date: 1971-01-25
Publication date: 1973-04-10
Anticipated expiration: 1990-04-10
Also published as: DE2201625A1; FR2124798A5; GB1339405A

Abstract

An acceleration enrichment signalling means for a fuel system used to supply fuel to an internal combustion engine in which the additional fuel requirement signal is generated so that additional fuel may be provided to the engine before air flow to the engine increases. The present invention provides mechanical and electrical means for working in combination with specialized circuitry to provide an increase in the fuel flow to the engine prior to any increase in air flow to thereby prevent any discontinuity in engine operation which may be caused by lags in fuel flow due to the electrical and mechanical characteristics of the main fuel system and of the engine.

Description

ilnited States Patent 1 11] 3,726,261 Sauer I 51 Apr. 10, 1 973 [54] ACCELERATION ENRICHlVIENT SIGNALLING MEANS FOR Primary Examiner-Laurence M. Goodridge ELECTRONIC FUEL SYSTEMS AttorneyRobert A. Benziger and Plante, Hartz, [75] Inventor: Rudolf G. Sauer, Ithaca, NY. Smth & Thompson [73] Assignee: The Bendix Corporation, Southfiel d, [57] ABSTRACT Mlch' An acceleration enrichment signalling means for a fuel [22] Filed: Jan- 25, 1971 system used to supply fuel to an internal combustion [21] Appl' No; 109 278 engine in which the additional fuel requirement signal is generated so that additional fuel may be provided to the engine before air flow to the engine increases. The [52] Cl "123/32 EA, 123/119 R, 123/140 MC present invention provides mechanical and electrical [51] Int. Cl ..F02m 51/00 means f working in Combination with specialized [58] Fleld of Search 123/32, 32 EA, 1 l9, Circuitry to provide an increase i the fuel flow to the 123/103 140 MC engine prior to any increase in air flow to thereby v prevent any discontinuity in engine operation which [56] References cued may be caused by lags in fuel flow due to the electrical UNITED STATES PATENTS and mechanical characteristics of the main fuel system and of the engine. 3,581,723 6/1971 Scholl ..l23/32 EA 3,272,187 9/1966 Westbrook et a1. 3 Claims, 6 Drawing Figures 2,361,206 10/1944 Hoppe ..l23/l03 E B14 77' ER) TEMPEIFHTURE SENSOR ELECTfiM/C TIMING PIC/(1U PAHifJI'LlJ 1 mm 3. 726,261

SHEET 1 BF 3 BA TTER) TE M PEA 1? TUAE SENSOR 12) ELECTRON/C TIM/N6 CONTROL '1 PIC/(UP UNIT 1 NVEN T OR.

Add 5M8! WITNESS: 4? f f gm $737k QMAW PATEi-HEU 3,726,251

SHEET 2 OF 3 INVENTOR.

ATTORN E Y ACCELERATION ENRICIIMENT SIGNALLING MEANS FOR ELECTRONIC FUEL SYSTEMS CROSS-REFERENCE TO RELATED APPLICATION This invention is related to commonly assigned, copending application Ser. No. 109,277 filed in the name of Todd L. Rachel on Jan. 25, 1971 titled Aeceleration Enrichment Circuitry for Electronic Fuel System.

BACKGROUND OF THE PRESENT INVENTION Field of the Invention The present invention relates generally to the field of electrical and electronic fuel control systems. More particularly, the present invention relates to that portion of the above noted field concerned with fuel injection systems for automotive type internal combustion engines. Specifically, an improved acceleration enrichment means is provided for an electronic fuel injection system adapted for automotive applications in which metered amounts of fuel are provided to more than one cylinder at a time.

BACKGROUND OF THE INVENTION In order to provide the smooth operation which the automotive operator demands from his vehicle, it has been recognized that some form of acceleration enrichment must be provided so that the vehicle will promptly respond to an instantaneous change in operational demands placed upon the engine. In those fuel systems in which injection of the various engine cylinders is accomplished by grouping those cylinders and injecting different groups in sequence, there exists a need for acceleration enrichment in view of the fact that there will be a specific time delay between the command to accelerate and the next injection pulse when the command would becomeeffective. In those systems in which injection of the individual cylinders takes place in a sequential fashion, the need for acceleration enrichment is reduced but is, however, desirable so that the engine will demonstrate a smooth, prompt response and will not produce excessive exhaust emissions.

Present acceleration enrichment systems are quite adequate to accomplish the broad objectives of providing additional fuel to accomplish the acceleration enrichment function under the various operating conditions encountered. However, two areas of difficulty have been encountered in even the most sophisticated acceleration enrichment mechanism. The first of these occurs during the range of vehicle operation characterized as light load, i.e., when the throttle is very slightly depressed. This is most often encountered when the vehicle is coming off the idle asfor instance initial acceleration from a stop. High engine and vehicle inertia combined with the maximum time period between successive injections makes it necessary that the air/fuel ratio be proper from one injection to the next at low engine speeds. However, when the throttle is opened to accelerate the engine, the additional available quantities of air cause the air/fuel ratio to become leaner. With the current trend in vehicle operation towards fuel systems which operate on the lean side (i.e., where the air to fuel ratio is in excess of about 17 to 1) this additional leanness would be excessive and will cause noticeable misfiring which would increase exhaust emissions and which would be generally unacceptable to the typical vehicle operator since it would make operation of the vehicle, particularly the acceleration of the vehicle up to driving or cruising speeds, in a smooth and efficient manner practically impossible. Secondly, even where misfiring does not occur, the increased leanness described above will cause the vehicle to lose power to the point that a command for acceleration will produce a momentary deceleration short of misfiring.

It is, therefore, an object of the present invention to provide an acceleration enrichment mechanism and signal generating system for electronic fuel control systems which will not cause the vehicle to lose power. It is a further object of the present invention to provide an acceleration enrichment mechanism which will provide additional quantities of fuel to be added to air/fuel mixture prior to increase in the air content thereof. It is a further object of the present invention to provide an acceleration enrichment device which will cause the air/fuel ratio to become less lean during the initial phases of vehicle acceleration. It is a specific object of the present invention to provide a signalling mechanism which will generate a command signal indicative of an acceleration demand prior to any increase in the air/fuelratio.

SUMMARY OF THE PRESENT INVENTION The present invention contemplates the addition of a lost motion connection between the accelerator pedal and the throttle plate. In addition, a potentiometer is coupled to the connection between the lost motion link and the accelerator pedal to move contemporaneously with the throttle pedal. The lost motion connection is resiliently biased in one direction so that initial movement of the accelerator pedal in a direction to increase vehicle air/fuel flow (and hence, speed) will cause the lost motion connection to move prior to movement of the throttle plate. In this fashion, the potentiometer will register a voltage change prior to movement of the throttle plate. This voltage change will be used to signal appropriate electronic circuitry to increase fuel flow to the injector valves of the fuel system prior to movement of the throttle plate, thus providing an increase in fuel flow prior to the increase in air flow. Thus, the present invention may be characterized by the presence of a lost motion connection between the throttle control and the throttle plate and the use of a signal generating potentiometer coupled to the throttle control mechanism so that changes in throttle setting will cause an instantaneous change in potentiometer setting followed by a change in throttle plate position a brief time later. This mechanism, when connected to appropriate electrical or electronic circuitry thus provides a means for achieving acceleration enrichment providing additional quantities of fuel prior to any increase in air to the air/fuel mixture.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic diagram of an electronic fuel control system adapted to control delivery of an air/fuel mixture to the combustion cylinders of an internal combustion engine.

FIG. 2 shows an illustrative schematic of the acceleration enrichment signalling mechanism of the present invention taken along the line 2-2 of FIG. 1.

FIG. 3 shows an electronic schematic diagram of a main computing circuit with which the present invention is of utility.

FIG. 4 shows an electronic circuit adapted to interface between the mechanism of FIG. 2 and the circuits ofFIGS. 3 and 5.

FIG. 5 shows an acceleration enrichment circuit useful with the present invention.

FIG. 6 shows an alternative embodiment of the lost motion link of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, an electronic fuel control system is shown which may utilize the present invention. The system is comprised of an electronic control unit 10 which receives signals from a timing pick-up 12, a temperature sensor 14, various parameter sensors 16 associated with a throttle body, and signals from the acceleration enrichment signalling mechanism 18. Parameter sensors 16 and acceleration enrichment mechanism 18 are attached to throttle body 20 which controls the flow of air into the engine. Throttle body 20 has a pair of air passages passing therethrough indicated as 22 and the effective crosssectional area of passages 22 is controlled by throttle plates 24. Throttle plates 24 are mounted on shaft 26 for controlled rotation therewith. The angular position of shaft 26 and hence of throttle plates 24 is controlled by throttle control means comprised of actuating means in the form of pedal 28 and suitable connecting linkage 30 through the intermediary of acceleration enrichment signalling mechanism 18.

The electronic control unit 10 is energized by battery 32 which also energizes those of the various sensors which require external energization. The output of the electronic control unit 10 is used to control the energization of an injector valve means 34 which is mounted in the intake manifold 36 and is adapted to introduce an air/fuel mixture for intake through intake valve 38, shown in an open position, into the combustion cylinder 40 of the internal combustion engine. Fuel is provided to injector valve means 34 from fuel tank 42 by means of pump 44 and suitable fuel supply and return lines 46.

Referring now to FIG. 2, the acceleration enrichment signalling mechanism 18 of FIG. 1 is shown in an illustrative schematic form. Mechanism 18 comprises a housing member 60, lost motion link 62, resilient biasing means 64, position control means 66, signal generator 68, in the form of a potentiometer, in this instance, and closing means 70. Lost motion link 62 is fixedly attached to the throttle plate shaft 26 to control rotation thereof. Lost motion link 62 includes a travel slot 72 and position control means 66 includes a pin member 74 mounted for movement in the travel slot 72. Resilient means 64 are operative to urge the pin member 74 to an extreme end of slot 72 while position control means 66 are operative to urge the pin towards the other extreme end of slot 72. Closing means 70 are operative to urge the lost motion link and, hence, the throttle plates 24, counterclockwise relative to the drawing of FIG. 2, to effect closing movement thereof upon release of tension in control means 66. Signal generating means 68 is operative to produce an output signal on signal lead 74 which is indicative of the instantaneous position of position control means 66. Lead 74 terminates in electrical port A and the output signal appearing thereat will be more fully discussed hereinbelow. Alphabetic designations are used herein to denote circuit points which are, or may be made, common to two or more figures of the drawing. In the preferred embodiment, I have selected a linear potentiometer 68 having its slider connected to the position control means 66 to provide this signal. Alternatively, potentiometer 68 could be located elsewhere in the circuit where its slider could be coupled to the control linkage 30 or the actuator 28. The potentiometer 68 receives a voltage input on lead 76 from the battery 32- as shown in FIG. 1 and the voltage on lead 74 is therefore directly proportional to the position of the position control means 66.

In operation, with the throttle plate at any angular position indicative of an engine operating situation, the application of pressure to throttle pedal 28 will cause, through the suitable linkage 30, a rightward (relative to FIG. 2) movement of position control means 66. This movement will change the instantaneous voltage appearing on lead 74 and, in this embodiment, will cause that voltage to increase. However, the initial movement of the position control means 66 will cause pin 74 to move rightward within slot 72 against the bias of resilient means 64 prior to any movement of the throttle plates 24. This can readily be arranged by insuring that the initial increment of movement of resilient means 64 requires less force than does movement of the lost motion link 62 against the bias of closing means and any friction present in the mounting of shaft 26. Thus, the voltage on lead 74 will change indicating a desire for acceleration prior to any movement of the throttle plate 24.

Referring now to FIG. 3, the main computing means of the electronic control unit 10 is illustrated. This circuit is shown as being energized by a voltage supply designated by B+ at the various locations noted. In the application of this system to an automotive fuel control system, the voltage supply could be the battery and/or battery charging system conventionally used as the vehicles electric power source. The man skilled in the art will recognize that the electrical polarity of the voltage supply, shown in FIG. 1 as battery 32, could be readily reversed.

The circuit receives along with the voltage supply, various voltage signal sensory inputs indicative of various operating parameters of the associated engine. Intake manifold pressure sensor 16 (one of the sensors 16 shown in FIG. 1) supplies a voltage indicative of manifold pressure, temperature sensor 14 is operative to vary the voltage across the parallel resistance to provide a voltage signal indicative of engine temperature and voltage signals indicative of engine speed are received at circuit port 102 from the timing pick-up 12. This signal may be derived from any source indicative of engine crank angle but is preferably from the engines ignition distributor.

The circuit 100 is operative to provide two consecutive pulses, of variable duration, through sequential networks to circuit location 104 to thereby control the on time of transistor 106. The first pulse is provided via resistor 108 from that portion of circuit 100 having inputs indicative of engine crank angle and intake manifold pressure. Termination of this pulse initiates a second pulse which is provided via resistor 110 from that portion of the circuit 100 having an input from the temperature sensor 14. These pulses received sequentially at circuit location 104, serve to turn transistor 106 on (that is, transistor 106 is triggered into the conduction state) and a relatively low voltage signal is present at circuit output port 112. This port may be connected, through suitable inverters and/or amplifiers (not shown) to the injector means (shown as 34 in FIG.

1) such that the injector means. are energized and thus open whenever the transistor 106. is on. Because the injector valve means are relatively slow acting, compared with the speed of electronic devices, the successive pulses at circuit location 104 will result in the injector valve means remaining open. until after the termination of the second pulse.

The duration of the first pulse is controlled by the monostable multivibrator network associated with

transistors

114 and 116. The presence of a pulse received via input port 102 will trigger the multivibrator into its unstable state withtransistor'ltl4 intthe conducting state and transistor 116 blocked .(or inthe nonconducting state). The period. of time during which transistor 114 is conductingwill. be controlled. by the voltage signal from manifoldv pressure sensor 16. Conduction of transistor 114] will cause the collector 114a thereof to assume arelatively low voltage closetothe ground or common voltage. This low voltage will cause the base 118b of transistor ll8 tolassume a low voltage below that required for transistor 118 to be triggered into the conduction state thus causing-transistor. 118 to be turned of Thevoltage at the collector 1180 will therefore rise towards the B+ value'andwillbe communicated via resistor 108ntocircuit location;10,4iwhere it.

will trigger transistor 106 into the on"or conduction state, thus imposing a relativelylow voltage at circuit port 112. As hereinbefore stated, the presence of a low voltage signal at circuit port 1l2will cause the selected injector valve means, toopenandremain open. When the voltage from the manifoldpressuresensor 16 has decayed to the value necessaryfor the 'multivibrator to relax or return to its stable condition,,transistor 116 will be triggered on and transistor 114 .will be turned transistor 126v has been biased .on and, with there sistor. network 128, constitutes a second current source. Current from both sources flows intothe base of transistor 130 thereby holding thistransistor on. which results in a low voltage at the'collector 130a. This low voltage is communicated to the base. of transistor 106 via resistor 110.

When transistor 114 turns off signalling termination of the first pulse, transistor 1 18 turns on and the potential at the collector 118a falls to a low value. The current from the current source comprised of transistor 120 and resistor network 122 now flows through the base of transistor 120 and the capacitor 124 ceases to charge. The capacitor will then have been charged with the polarity shown in FIG. 3 to a value representative of the duration of the first pulse. However, the potential at the collector of transistor 120 will be only slightly positive with respect to ground since only several pn junctions separate it from ground. This will impose a negative voltage on circuit location 132 which will reverse bias diode 134 and transistor will be turned off. This will initiate a high voltage signal from the collector of transistor 130 to circuit location 104 via resistor 110 which signal will retrigger transistor 106 on and the second injector means control pulse will appear at circuit port 112. The time duration between first and second pulses will be sufficiently short so that the injector means will not respond to the brief lack of signal.

While the diode 134 is reversed biased, the current from the current source comprised of transistor 126 and resistor network 128 will be flowing through circuit location 132 and into the capacitor 124 to charge the capacitor to the point that circuit location 132 will again be positively biased with respect to ground. This willthen forward bias diode 134 and transistor 130 will turn back on". This will terminate the second pulse and the injector valve means will subsequently close.

The duration of the second pulse will be a function of the time required for circuit location 132 to become sufficiently positive for diode 134-to be forward biased. This, in turn, is a function of the charge on capacitor 124 and the magnitude of the charging current supplied by the current source comprised of transistor 126 and resistor network 128. The charge on capacitor 124 is, of course, a function of the duration of the first pulse. However, the rate of charge (i.e., magnitude of the charging current) is a function of the base voltage at transistor 126. This value is controlled by the voltage divider networks136 and 138 with the effect of network 138 being variably controlled by the engine temperature sensor 14.

Thecircuit of FIG. 3 contains three circuit points denoted'by alphabetic designations. These are circuit points C, Alternate C and E. Point'E and Alternate C are at the bases of transistors 106 and l26respectively and point C is located within the network which establishes the voltage level applied to inductive pressure sensor 16.

Referring now to FIGS. 3, 4 and 5, a circuit useful with my invention will be described. The circuit of FIG. 4 comprises an amplifier portion 200, an analog signal generating portion 202 and a controlled switch portion 204. The amplifier portion 200 is energized by B+ as noted and receives a signal from the acceleration enrichment signalling mechanism 18 (of FIG. 1) through signal input port point A. An output signal from amplifier 200 is coupled to analog signal generating portion 202 and controlled switchingportion 204 from circuit location 206 via

leads

208 and 210. Analog signal generating portion 202 is operative toprovide a voltage signal at circuit point C for a period of time following receiptof an input signal. Controlledsignal portion 204 is operative to provide an output signal of variable duration at circuit point D following receipt of an input signal.

Amplifier portion 200 is comprised of transistor 212 and

resistor

214 and 216. This circuit is arranged as a common-emitter amplifier with resistor 214 being the load resistor. Thus, the voltage at the collector terminal 2126 of transistor 212 will increase as the voltage at the base of the transistor (in this instance, the voltage output of the potentiometer output lead 74 and port A) decreases. Therefore, the collector terminal voltage will represent the instantaneous position control means setting. The gain of this amplifier configuration is the ratio of the resistance of resistor 214 to that of resistor 216. By proper selection of resistive values, the switching control circuit 200, and thus the

circuits

202 and 204 can be made as sensitive or insensitive to slight throttle movements as desired.

Analog signal generating circuit 202 is comprised of capacitor 218, resistor 220, and transistor 222. The capacitor 218 interconnects the base of transistor 222 to the output of switching control circuit 200 and the resistor 220 interconnects the base of transistor 222 and the emitter of the transistor-222 and provides that, under steady state conditions, transistor 222 will be switched off.

The emitter of transistor 222 is connected to point C. Point C may be connected to either circuit point C or Alternate C (in FIG. 3) and, under steady state conditions will be at an electrical potential determined by the circuit potential to which point C is connected and the amount of conduction of transistor 222.

Under steady state conditions, capacitor 218 will behave as an open circuit and resistor 220 will maintain the voltage at the base of the transistor 222 at or below the voltage at the emitter of the transistor 222. If the voltage at circuit location suddenly rises (due to a change in the base voltage indicative of an acceleration demand) the voltage at the base of transistor 222 will rise by an equivalent amount and transistor 222 will begin to conduct. The amount of conduction will be determined by the basev voltage of transistor 222 and this will be determined as a function of the voltage at circuit location 206 due to the capacitive coupling and also as a function of the time period over which the voltage increased since the capacitor 218 will immediately begin to charge (or discharge) to a new steady state level.

The output signal from amplifier portion 200 is also provided to controlled switch 204. This circuit 204 is comprised of a capacitor 224, a bias network comprised of

resistors

226, 228, 230 and 232, and emitter- .coupled pair of

transistors

234 and 236,

resistors

238 and 240 and switching transistor 242. The bias network of

resistors

226, 228, 230 and 232 is arranged so that the potential at the base of transistor 236 exceeds the potential at the base of transistor 234 (with respect to the ground or common potential) therefore biasing transistor 234 on and turning transistor 236 off. The base of transistor 242 is connected to the collector of transistor 236 so that the electrical state of transistor 242 will coincide with the state of transistor 236. The collector of transistor 242 is connected to circuit point D and the potential at D will be determined by the resistances of resistors 304, 306 whenever transistor 242 is off and will be at the ground or common potential whenever transistor 242 is on.

The capacitor 224 functions as an open circuit under steady state conditions and responds to voltage changes at circuit location 206 in the same manner as does capacitor 218. The emitter-coupled pair of

transistors

234, 236 is arranged to respond only to voltage changes at circuit location 206 which are sufficiently great that the capacitive coupling between circuit location 206 and the base of transistor 234 will raise the base voltage above the voltage at the base of transistor 236 established by the voltage divider effect of

resistors

230 and 232. Since the capacitor 224 will begin to charge (or discharge) immediately upon a voltage change at circuit location 206, the magnitude of that voltage change and the rate of that change will influence circuit 204. That is, if the magnitude of the change is small, or if the rate of the change is low, the voltage at the base of transistor 234 may not change sufficiently for it to turn off and thereby cause transistors 236 and 242 to turn on.

Referring now to FIG. 5, a circuit 300 is shown. Circuit 300 is adapted to generate a single pulse of fixed duration for ultimate application to the injector valve means most recently energized. Circuit 300 is comprised of normally conducting transistor 302, bias establishing resistors 304 and 306,

load resistors

308 and 310, zener diode 312, capacitor 314 and diode means 316.

Referring now to the operation of FIG. 4 in conjunction with the circuits of FIGS. 3 and 5, and the mechanism of FIGS. 1 and 2, an initial state of vehicle operation at a steady throttle setting will be presumed. Depression of throttle 28 will cause an instantaneous movement of linkage 30 which will cause the setting of potentiometer 68 to change. Therefore, the voltage picked off by lead 78 and appearing at circuit point A will decrease. This initial movement will have the effect of stressing spring 64 so that the position of throttle plate 24 will initially be unchanged. The decrease in voltage signal received at the base of transistor 212 will cause the voltage at the collector thereof to increase by an amount representative of the change in voltage at circuit point A multiplied by the gain factor of the amplifier configuration. Thus, the voltage at circuit location 206 will rise. The effect of this increase in voltage will be applied via

leads

208 and 210 to the analog signal generating circuit 202 and the controlled switch circuit 204.

This voltage change will be applied to capacitor 218 in the analog signal generating circuit. Since the voltage appearing across a capacitor cannot change instantaneously, the voltage being applied to the base of transistor 222 will also increase. This will have the effect of increasing the conductivity of transistor 222 and will cause the voltage at the emitter of that transistor to increase so that the voltage at circuit point C will also increase. This voltage may be applied to either of the locations noted in FIG. 3 as circuit points C and Alternate C. The effect of this voltage change will be to vary the established voltage levels in FIG. 3 so that the pulse length of the pulses established by that circuit will be increased by an amount proportional to the voltage change at circuit point C. This change in voltage will be a function of the amount of change in the desired throttle control setting, i.e., the change in voltage at circuit point A, and will also be a function of the speed with which the throttle position has been changed since the charge on the capacitor will begin to change immediately. Thus, the magnitude of the effect produced on the circuit 100 will be in proportion to the mag nitude of the change in throttle position as well as the speed with which that change was made. When a new steady state position is established for the throttle setting, the voltage at circuit location 206 will be established at some new steady value and the charge on capacitor 218 will adjust to this new value. The rate of charge of the capacitor 218 will be a function of the RC time constant of the circuit 202 and will, therefore, control the amount of voltage change realized within circuit 100 and hence, the magnitude and duration of the effect imposed on circuit 100 by analog signal generating circuit 202. The result of this will be a lengthening of one or both of the injection command pulses appearing at circuit port 112 (of FIG. 1). The amount of pulse duration increase will thereafter shorten as a function of the RC time constant of circuit 202 and the voltage at circuit location 206 (i.e., as a function of the total change and speed of change of throttle control setting). This circuit 202 will, therefore, provide for additional fuel for acceleration in an amount which varies approximately as engine need for enrichment varies.

The change in throttle position and, hence, the voltage at circuit location 206 will also be experienced by capacitor 224. This will have the effect of increasing the voltage at the base of transistor 234. If the throttle position change is of sufficient magnitude, the voltage at the base of transistor 234 will rise above that at the base of transistor 236 and, due to the emitter-coupled pair configuration, transistor 234 will be turned of and transistor 236 will be turned on. Conduction of transistor 236 will cause current to flow through resistor 240 so that a voltage drop is experienced thereacross. This voltage difference will be applied to the emitter-base junction of transistor 242 causing that transistor to begin to conduct so that a ground, or common, potential signal will be experienced at circuit point D. Circuit point D is connected to the input point D of circuit 300 in FIG. 5 and the presence of this ground potential will terminate current flow through resistor 206 so as to cause transistor 302 to be turned off. This will cause the voltage applied to capacitor 314 to increase rapidly and this increase will be applied by way of the diode means 316 to circuit point B. Circuit point B is connected directly to control transistor 106 so that the presence of a signal at point E will cause transistor 106 to go into conduction, and an output signal will be realized at circuit port 112. This signal will directly control the energization of the injector valve means 34 currently electrically coupled to circuit port 112 (of FIG. 1). The magnitude of this signal will be a function of the time required to discharge capacitor 314 to the proper level and may, therefore, be established as a constant value.

Referring now to FIG. 6, an alternative form of the lost motion link is illustrated having slot 172 and pin 174 slidingly received therein. The resilient biasing means 167 is mounted to one side of the lost motion link 162. It is thus out of linewith pivot 26 and its effect will, therefore, be somewhat different than the effect of that shown in FIG. 2 embodiment.

While a preferred embodiment of the invention has been disclosed, it will be apparent to those skilled in the art that changes may be made to the invention as set forth in the appended claims, and, in some cases, certain features of the invention may be used to advantage without corresponding use of other features. Accordingly, it is intended that the illustrative and descriptive materials herein be used to illustrate the principles of the invention and not to limit the scope thereof.

1 claim:

1. In a fuel control system of the type having elec- -tronic circuitry to generate electrical signals for controlling actuation of injector valve means to thereby control fuel delivery to an internal combustion engine having a throttle-valve controlled air intake and means externally positionable by an operator controlled linkage mechanism to variabley control the throttle valve position, the improvement comprising means providing a lost-motion mechanical connection between the throttle valve and the operator positionable throttle valve control linkage, resilient means for biasing the lost-motion connection towards one extreme position corresponding to the positon assumed in the absence of an operator signal, and resistive electrical signal generating means connected to the operator positionable throttle valve control linkage operative to generate an electrical signal indicative of the instantaneous throttle valve control linkage setting whereby opening movement of the throttle valve control linkage will cause a change in the generated electrical signal in synchronism with the motion of the throttle valve control linkage and prior to a change in the throttle valve positon and means for communicating said electrical signal to the electronic circuitry for controllably altering the injector valve means actuation whereby fuel delivery may be increased prior to increases in air flow through the air intake means.

2. The system as claimed in claim 1 wherein said signal generating means comprise resistive potentiometer means having a wiper arm porton and a contact member and said wiper arm portion is coupled to said throttle control means and said contact member is moved in response to said wiper arm portion to provide a variable voltage signal indicative of said wiper arm portion position.

3. An air intake throttle control for internal combustion engines for use with electronic fuel control systems comprising:

a throttle body adapted to be attached to the air intake of the engine;

throttle valve means within said body positionable to control air flow therethrough;

throttle valve position control means coupled to said throttle valve means responsive to an operator signal operative to variably position said throttle valve means within said throttle body;

said throttle valve position control means including a lost-motion linkage member whereby motion of said throttle valve position control means may precede a change in the position of said throttle valve means relative to said throttle body; and

electrical means including a resistive element connected to said throttle valve position control means such that the lost-motion linkage member is interposed between the electrical means and the communicating said electrical signal to the elecihfome Valve means 581d electrical means tronic fuel control system whereby fuel delivery to cooperative with the lost-motion member to product an electrical signal indicative of a movement commended by the operator prior to the 5 movement of the throttle valve means said electrical means further including means for the engine may be increased in response to said electrical signal prior to an increase in air flow through said throttle body.

Claims

1. In a fuel control system of the type having electronic circuitry to generate electrical signals for controlling actuation of injector valve means to thereby control fuel delivery to an internal combustion engine having a throttle-valve controlled air intake and means externally positionable by an operator controlled linkage mechanism to variabley control the throttle valve position, the improvement comprising means providing a lost-motion mechanical connection between the throttle valve and the operator positionable throttle valve control linkage, resilient means for biasing the lost-motion connection towards one extreme position corresponding to the positon assumed in the absence of an operator signal, and resistive electrical signal generating means connected to the operator positionable throttle valve control linkage operative to generate an electrical signal indicative of the instantaneous throttle valve control linkage setting whereby opening movement of the throttle valve control linkage will cause a change in the generated electrical signal in synchronism with the motion of the throttle valve control linkage and prior to a change in the throttle valve positon and means for communicating said electrical signal to the electronic circuitry for controllably altering the injector valve means actuation whereby fuel delivery may be increased prior to increases in air flow through the air intake means.

3. An air intake throttle control for internal combustion engines for use with electronic fuel control systems comprising: a throttle body adapted to be attached to the air intake of the engine; throttle valve means within said body positionable to control air flow therethrough; throttle valve position control means coupled to said throttle valve means responsive to an operator signal operative to variably position said throttle valve means within said throttle body; said throttle valve position control means including a lost-motion linkage member whereby motion of said throttle valve position control means may precede a change in the position of said throttle valve means relative to said throttle body; and electrical means including a resistive element connected to said throttle valve position control means such that the lost-motion linkage member is interposed between the electrical means and the throttle valve means, said electrical means cooperative with the lost-motion member to product an electrical signal indicative of a movement commended by the operator prior to the movement of the throttle valve means ; said electrical means further including means for communicating said electrical signal to the electronic fuel control system whereby fuel delivery to the engine may be increased in response to said electrical signal prior to an increase in air flow through said throttle body.