US2893370A

US2893370A - Fuel supply system

Info

Publication number: US2893370A
Application number: US657154A
Authority: US
Inventors: Albert H Winkler
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1957-05-06
Filing date: 1957-05-06
Publication date: 1959-07-07
Anticipated expiration: 1976-07-07
Also published as: DE1820085U

Description

y 7, 1959 A. H. WINKLER 2,893,370

FUEL SUPPLY SYSTEM Filed May 6, 1957 5 Sheets-Sheet 1 ALTITUDE COM PENISA'I'OR ENGINE TEM PE'RATURE COMPENSATOR.

ELECTRONIC CO NTRO 3- INVENTOR.

Ga: W Y I m I ERT H. INKLER \aj ALB w A TTORNE Y.

' July 7, 1959 A. H. WINKLER FUEL SUPPLY SYSTEM 5 Sheets- Sheet 2 Filed May 6, 1957 ALBERT H, wiWTi-R.

ATTORNEY.

July 7, 1959 A. H. WINKLER 2,893,370 FUEL SUPPLY SYSTEM Filed May 6, 1957 5 Sheets-Sheet 3 74 76 36 5a 96 V 64 36 I 1 70 P /00 I 54 2& 56 76 48 g I O 0 ALBERT H. WWZTER A T TORNE Y July 7, 1959 A. H. WINKLER FUEL SUPPLY SYSTEM Filed May 6, 1957 5 Sheets-Sheet 4 ALBERT H. WINKLER,

ATTURIVEY' July 7, 1959 A. H. WINKLER FUEL SUPPLY SYSTEM 5 Sheets-Sheet 5 Filed May 6, 1957 IBOK IIOK

E M C D E I D N 5 m v E \fi s WM K K K K. K0 0 O 0 w W 5 w w 2 INVENTORY ALBERT H. WINKLER ATTORNEY.

United States Patent FUEL SUPPLY SYSTEM Albert H. Winkler, Elmira, N.Y., assig'nor to Beudix Aviation Corporation, South Beud, lnd., a corporation of Delaware 2 Application May 6, 1957, Serial No. 657,154 Claims. (Cl. 123-179) The present invention relates generally to an electrical fuel supply system and more particularly to a starting and warm-up control for such a system.

In U.S. application Serial No. 637,852, filed February 4, 1957, assigned to the assignee of the present invention there is disclosed and claimed an electrical fuel supply system wherein fuel under pressure is delivered in the form of pulses of controlled timed duration to the induction passage of an engine. The time duration of a fuel pulse is controlled by an electrical timing device having a time constant comprised of impedance means which may be varied as a function of engine operating conditions.

The present invention is particularly adapted for regulating a fuel supply system of the type disclosed and claimed in said application, Serial No. 637,852 during the starting and warm-up operationof an engine; and comprises, in a preferred embodiment, an engine temperature responsive element for increasing the value of the impedance means when cold and an element energized during starting of the engine for providing additional 1ncrease in the value of the impedance means.

It is an object of the present invention to provide a simple reliable and accurate control for an electrical fuel supply system to increase the fuel supply to an engine during starting and warm-up operation thereof.

Other objects and advantages will be readily apparent in the following detailed description taken in connection with the appended drawings in which:

Figure 1 is a schematic view of a fuel supply system embodying the present invention;

Figure 2 is a circuit diagram of the electronic control shown in Figure 1;

Figure 3 is a front view of the throttle body shown in Figure 1;

Figure 4 is a side view of the throttle body;

Figure 5 is a view taken along line 5--5 of Figure 1;

Figure 6 is a sectional'view taken along line 6--6 of Figure 2; and

Figure 7 is a graph illustrating certain operating conditions of the control of my invention. I Referring now to the drawings and more particularly to Figure 1 numeral 10 designates a fuel tank,'12 a conduit adapted to connect the fuel tank to a fuel nozzle 14. A pump 16 is mounted in conduit 12 for placing the fluid therein under pressure. Fuel supplied by pump 16 in excess of the quantity discharged through the nozzle 14 is returned to the fuel tank through conduit Pump 16 is adapted to deliverfuel at a controlled constant or variable pressure to the injector nozzle 14. The injector valve 14 is periodically opened for a controlled time duration whereby the quantity of fuel injected into the. inductionpassaget22 .varies. as a function of the time duration of nozzle opening and the pressure of fuel supplied to the nozzle.

The control for the nozzle 14 includes throttle body assembly 30, electronic control 32 and trigger-distributor unit 34. In operation, the trigger-distributor unit 34 triggers or energizes the electronic control 32 periodically as a function of engine speed. Upon energization, the electronic control 32 produces a pulse of electrical energy the width or time duration of which is dependent upon various conditions which effect engine operation. Engine operating conditions are sensed by various elements in the throttle body assembly 30 and are supplied to the electronic control by appropriate conductors. The output of the electronic control 32 is connected to the distributor portion of the trigger-distributor unit 34 whereby a pulse of electrical energy is connected to a solenoid in the appropriate nozzle in accordance with a predetermined sequence or with the firing order of the associated engine. The solenoids in nozzles 14 remain energized for a period of time dependent upon the width or time duration of the electrical pulse.

The throttle body assembly 30 includes a throttle body 36 containing

induction passages

38 and 40 with

throttle valves

42 and 44 respectively mounted therein on a shaft 46. The

induction passages

38 and 40 are in communication with the induction passage 22. A throttle lever 48 is secured to shaft 46 and is adapted for actuation by a conventional accelerator pedal 50 through a rod 52. A starting and Warm-up control 54 is secured to the throttle body 36 and is provided with a shaft 56 which is connected with a fast idle cam 58 by means of a lever 60, rod 62 and lever 64. Rod 62 is provided with a turned over end 66 which is mounted in a slot 68 formed in the lever 64. Lever 64 is rotatably mounted on the throttle body 36 on a shaft 70 on which is mounted a torsion spring 72 the

ends

74, 76 of which are disposed on opposite sides of the end portion 66 of rod 62. The throttle lever 48 carries an adjustable screw 78 which is adapted to engage the fast idle cam 58 to determine the fast idle position of the

throttle valves

42 and 44. A screw 80 is threadedly received in a boss formed on the throttle body 36 and is disposed to engage throttle lever 48 to determine the slow idle position of the throttle valves. An arm 81 formed on throttle lever 48 is adapted to engage a pin 83 on fast idle cam 58 when the throttles are moved to substantially wide open positions to rotate shaft 56 toward one of its extreme positions.

A device 82 responsive to induction passage pressure is mounted on the throttle body 36 and is operatively connected to a potentiometer 84 to actuate the same as a function of change in induction passage pressure. A potentiometer 86 is mounted on the throttle body 36 for actuation by throttle shaft 46 and acceleration control 88 which may be of the type disclosed and claimed in U.S. application Serial No. 622,618, filed November 16, 1956, in the names of S. G. Woodward et al. is also mounted on the throttle body 36. Altitude compensator 90 and engine temperature compensator 92 may be conveniently mounted as desired and are connected to the electronic control 32 by appropriate conductors. The starting and Warm-up control 54, accelerator control 88 and

potentiometers

84 and 86 are connected to the electronic control 32 by appropriate conductors.

As best shown in Figures 5 and 6 the starting and warm-up control 54 includes a housing 94 which is secured to the throttle body 36 by suitable bolts 96. A conduit 98 connects the interior of housing 94 with an induction passage downstream of the throttle valve. A conduit 100 connects the interior of housing 94 with a source of heat, which may be the exhaust duct of the engine (not shown). A heat responsive member or thermostat 102 is mounted in housing 94 with one end fixed to shaft 56 and the other end hooked about a lever 104 which is pivoted at 106 in the housing. A rod 108 connects lever 104 with a piston or armature 110 which is reciprocably disposed in the magnetic field of solenoid 112. Solenoid 112 is connected by a read 114 to ground or reference potential and by a lead 116 to the starting motor circuit 118. Circuit 118 connects starting motor 120 through a switch 122 to a source of electrical power such as a battery designated 124. A spring 126 reacts between the end wall of housing 94 and the armature 110 to urge the rod 108 and lever 104 to the full line position shown in Figure 5. When the solenoid 112 is energized by closing switch 122 in the starting motor circuit, armature 119 is moved in opposition to spring 126 to position the lever 104 as shown by the dotted lines in Figure 5. A potentiometer 128 is mounted on shaft 56 for actuation thereby.

Referring now to Figure 2, the

potentiometers

84, 86 and the accelerator, altitude and engine temperature controls are collectively and schematically represented by the variable resistance designated R Potentiometer 128 is represented by the variable resistor designated R A source of power E is connected through a switch 130 and lead 132 to a triggering switch 134 which is mounted on a shaft 136 in the trigger-distributor unit 34. Shaft 136 is adapted to be driven as a function of engine speed by suitable means (not shown). One contact of triggering switch 134 is connected to lead 132 by a conductor 133. The other contact of triggering switch 134 is connected to ground or reference potential by a conductor 140. Triggering switch 134 is adapted to be periodically closed by rotation of shaft 136 as a function of engine speed. The actuation of switch 134 produces a series of pulses in lead 142 substantially as shown in Figure 2. Each of these pulses is subsequently transformed into a pair of negative and positive voltage spikes by a capacitor 144. A rectifier 146 connected to capacitor 144 passes the negative spikes only to the base 148 of a normally nonconducting transistor 150 of a monostable multivibrator designated generally at 152. The collector 154 of transistor 150 is connected to the base 156 of a normally conducting transistor 158 of multivibrator 152 through lead 160 and capacitor C. When the negative voltage spike is applied to base 148, transistor 150 commences to conduct whereby the potential in lead 160 is increased sufficiently to drive transistor 158 into a non-conducting state. The time that transistor 158 remains non-conductive is determined by the decay rate of capacitor C which in turn is a function of the value of the time constant R R C. When the voltage on capacitor C as applied to the base 156 reaches a predetermined value transistor 158 again becomes conductive and transistor 151) is rendered non-conductive. Transistor 150 remains non-conductive until retriggered by a negative voltage spike. The action of the multivibrator 152 produces a pulse in the output lead 162 the width or time duration of which is controlled as a function of the time constant R R C. The amplitude of the pulse in lead 162 varies from the normally conducting voltage E to substantially zero. The output of the multivibrator 152 is coupled to amplifier 172 through lead 162, capacitor 166 and lead 168. A diode 17 clamps lead 168 to lead 132 to insure a substantially constant steady state voltage E in lead 163 with reference to the voltage in lead 132. 'A pulse in lead 162 produces a pulse in lead 168 of substantially the same width as the pulse in 162. The amplitude of the pulse in lead 168 varies from the reference voltage E to a lower voltage E The pulse in lead 168 causes transistor 172 to conduct. The time that transistor 172 conducts is determined by the duration of the pulse in lead 168 which in turn is determined as a function of the time constant R R C. The output of transistor 172 is amplified by cascaded transistors 174 and 176. The output of power amplifier 176 is connected by the lead 178 to a commutatorring 130,000 ohms to approximately 200 ohms.

180 in a distributor portion of trigger distributor unit 34-. The wiper arm 182 mounted on shaft 136 successively connects ring 180 to contact segments 184. The contacts 184 are respectively connected to solenoids 186 in the injector nozzles 14. The connections between the contacts 184 and solenoids 186 are arranged so that successive engagement of the arm 182 with the contacts 184 energizes the solenoids in accordance with a predetermined order or with the firing order of the engine with which the fuel supply system is associated. Energization of a solenoid 186 opensa normally closed valve 188 in the nozzle 14 to permit fuel to flow from the conduit 12 to the induction passage 22. The time duration of fuel flow is determined by the time duration of energization of the solenoid 186.

The potentiometer 128 is wound to provide a resistance curve versus rotation of shaft 56 substantially as shown in Figure 7. Upon energization of the starting motor circuit 118 solenoid 112-moves piston and rod 108 to position lever 104 as shown by the dotted lines in Figure 5 wherein the shaft 56 is rotated to position the wiper of potentiometer 128 at substantially zero degrees of angular travel wherein the resistance of potentiometer 128 is at its maximum value. The resistance R of potentiometer 128 is proportioned with respect to resistance R so that when R is at its maximum'value a substantial increase in the timeduration of electrical pulse from control 32 is obtained. When the starting motor circuit 118 is de-energized thespring 126 moves piston 110 and rod 108 to position lever 104 in substantially the full line position shown, in Figure 5. Inthis position the resistance R of potentiometer 128 is decreased substantially. In the specific example illustrated in Figure 7 movement of .lever 104 from the dotted line position to the full line position of Figure 5 reduces the resistance R from As the thermostat 102 warms up the resistance R is further decreased from 200 ohms to substantially zero ohms. The effect of the starting and warm up control 5'4 is to provide'a substantial enrichment during the starting operation of the engine and substantially less enrichment during the warm up.

In describing a specific embodiment of my invention the time constant R R C has been described with reference to particular resistance and capacitance combinations. It is to be'understood, however, that the time constant may becomprised of various combinations of impedance means and that the starting enrichment and warm up control 54 may vary a resistance, inductance, or capacitance or combination thereof.

Although aparticular embodiment ofmy invention has been described it will be understood by those skilled in the art that the objects of the invention may be attained by theuse of. constructions different in certain respects from that disclosed without departing from the underlying principles of the invention.

I claim:

1. A fuel supply .systemfor an engine having a starting circuit comprising a source of fuel under pressure, a conduit connecting said source to said engine, an electrically actuable valve in said conduit for controlling the time duration of fuel flow therethrough, an electrical timing device operatively connected to said valve for controlling the time duration of current flow to said valve, means for controlling said device, a thermostat responsive to engine temperature operatively connected to said means, and a solenoidactuable by said starting circuit operatively connected to said thermostat.

2. Afuel supply system for an engine comprising a source of fuel underpressure, a conduit connecting said source to the engine, a valve in said conduit, electrical means for actuatingsaid valve, a circuit for said means, a timing device having a timeconstant in said circuit for controlling the time duration of current flow in said ciricuit, impedance means in said circuit for varying said time constant, means responsive to engine temperature for controlling said impedance means, and means actuable during engine starting and operatively connected to said impedance means whereby said impedance means is varied to increase said time constant.

3. A fuel supply system for an engine having an induction passage with a throttle therein comprising a source of fuel under pressure, a conduit connecting said source to said passage, a valve in said conduit, electrical means for actuating said valve, a circuit for said means, a device in said circuit having a time constant for controlling the time duration of current flow in said circuit, variable impedance means in said circuit for varying said time constant, a thermostat responsive to engine temperature operatively connected at one end to said impedance means, a fast idle cam operatively connected to said one end of said thermostat and disposed to limit the closing of said throttle, and means actuable during the starting operation of said engine operatively connected to the other end of said thermostat to effect movement of said impedance means and said cam toward their respective maximum effective positions.

4. A fuel supply system for an engine having an induction passage with a throttle therein, comprising a source of fuel under pressure, a conduit connecting said source to the engine, a valve in said conduit, electrical means for actuating said valve, a circuit for said means, means in said circuit for controlling the time duration of current flow in said circuit, a thermostat responsive to engine temperature operatively connected to said second mentioned means, and means actuable by movement of said throttle to substantially wide open position for controlling said second mentioned means.

5. A fuel supply system for an engine having a starting motor circuit and an induction passage with a throttle therein comprising a source of fuel under pressure, a conduit connecting said source to said passage, a valve in said conduit, electrical means for actuating said valve, a circuit for said means, a timing device in said circuit, impedance means forming a time constant in said device, a thermostat responsive to engine temperature operatively connected to said impedance means, means energized by said starting motor circuit for varying said impedance means and means responsive to movement of said throttle to substantially wide open position for varying said impedance means.

References Cited in the file of this patent UNITED STATES PATENTS 1,803,666 French May 5, 1931 2,664,872 Erickson et a1. Jan. 5, 1954 2,846,995 Foltz Aug. 12, 1958