US3747577A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature-dependent resistance arrangement for controlling fuel injection as a function of air intake
Assignee: Robert Bosch GmbH
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Filing: 1971-08-30
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Granted: 1973-07-24
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Expires: 1991-08-30
Abstract
Abstract A temperature-dependent resistor is placed in path of air intake. Resistor forms part of a bridge circuit. Amplifier input connected to the diagonal of bridge circuit, amplifier output connected in parallel with the two branches of bridge. Resulting feedback circuit maintains temperature-dependent resistor at a constant temperature by changing current therethrough to compensate for different cooling effects of air stream. Output voltage of amplifier constitutes measure of regulator current through temperature-dependent resistor and therefore measure of air intake. Circuits using amplifier output voltage to control fuel injection also illustrated.
Inventors
- 👤 H Mauch
- 👤 D Handtmann
- 👤 H Knapp
- 👤 H Zeller
- 👤 E Zehender
- 👤 G Haug
- 👤 W Reichardt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:56
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/18; F02D41/187; G; G01; G01F; G01F1/00; G01F1/68; G01F1/696; G01F1/698
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
203 words
In an internal combustion engine, an arrangement for measuring the flow rate of the intake air and furnishing an air intake signal in correspondence thereto, comprising, in combination, bridge circuit means having at least one temperature dependent resistor, said temperature dependent resistor having resistance varying as a function of temperature and therefore as a function of current flowing therethrough, positioned in the path of said air, whereby changes in said rate of flow change the cooling effect of said air thereby changing said resistance, said bridge circuit means having input terminals connected to said temperature dependent resistor for receiving a control current, changes in said control current changing said resistance, said bridge circuit means further having output terminals for furnishing an output voltage varying as a function of said resistance of said temperature dependent resistor; and amplifier means having an input connected to said output terminals and an output connected to said input terminals, for furnishing a control current varyin dependence on said output voltage in such a manner that said resistance of said temperature dependent resistor remains substantially constant independent of said flow of air, whereby said control current constitutes a measure of said air flow, thereby constituting said air intake signal.
Claim 2
Dependent Claim
203 words
In an internal combustion engine, an arrangement for measuring the flow rate of the intake air and furnishing an air intake signal in correspondence thereto, comprising, in combination, bridge circuit means having at least one temperature dependent resistor, said temperature dependent resistor having resistance varying as a function of temperature and therefore as a function of current flowing therethrough, positioned in the path of said air, whereby changes in said rate of flow change the cooling effect of said air thereby changing said resistance, said bridge circuit means having input terminals connected to said temperature dependent resistor for receiving a control current, changes in said control current changing said resistance, said bridge circuit means further having output terminals for furnishing an output voltage varying as a function of said resistance of said temperature dependent resistor; and amplifier means having an input connected to said output terminals and an output connected to said input terminals, for furnishing a control current varyin dependence on said output voltage in such a manner that said resistance of said temperature dependent resistor remains substantially constant independent of said flow of air, whereby said control current constitutes a measure of said air flow, thereby constituting said air intake signal.
Claim 3
Dependent Claim
28 words
An arrangement as set forth in claim 1, further comprising means furnishing a control voltage corresponding to said control current, said control voltage constituting said air intake signal.
Claim 4
Dependent Claim
49 words
An arrangement as set forth in claim 2, wherein said internal combustion engine further comprises fuel injection means, and regulator means connected to said fuel injection means and said closed loop control circuit means for controlling the quantity of injected fuel as a function of said air intake signal.
Claim 5
Dependent Claim
52 words
An arrangement as set forth in claim 2, wherein said fuel injection means comprise injection valve means; wherein the quantity of fuel injected varies as a function of fuel pressure at said injection valve means; and wherein said regulator means comprise means controlling said pressure in dependence on said air intake signal.
Claim 6
Dependent Claim
53 words
An arrangement as set forth in claim 2, wherein said fuel injection means comprise injection valve means; wherein the quantity of fuel injected varies in dependence upon the valve opening of said injection valve means; and wherein said regulator means comprise means controlling said valve opening in dependence upon said air intake signal.
Claim 7
Dependent Claim
81 words
An arrangement as set forth in claim 2, wherein said internal combustion engine operates with at least one intake phase per operating cycle; wherein said internal combustion engine further comprises a rotating shaft; wherein said injection means comprise timed injection means injecting fuel for a determined injection time per cycle, said timed injection means operating in synchronism with said rotating cam shaft; and wherein said regulator means comprise means varying said injection time as a function of said air intake signal.
Claim 8
Dependent Claim
32 words
An arrangement as set forth in claim 6, further comprising conversion means converting said air intake signal to a second signal corresponding to the total quantity of air intake per engine stroke.
Claim 9
Dependent Claim
51 words
An arrangement as set forth in clAim 7, wherein said conversion means comprise signal storage means; and switch means operated synchronously with said cam shaft for connecting said signal storage means to said output of said amplifier means when closed, thereby furnishing a sequence of pulses to said signal storage means.
Claim 10
Dependent Claim
25 words
An arrangement as set forth in claim 8, wherein said switch means are closed for a predetermined constant angle of rotation of said cam shaft.
Claim 11
Dependent Claim
70 words
An arrangement as set forth in claim 9, further comprising integrator means connected between said switch means and said signal storage means for furnishing an integrator output signal corresponding to the amplitude of said pulses multiplied by the time duration of said pulses; and wherein said signal storage means store the value of said integrator output signal at the end of each of said pulses in said sequence of pulses.
Claim 12
Dependent Claim
17 words
An arrangement as set forth in claim 10, wherein said signal storage means comprise peak-responsive rectifier means.
Claim 13
Dependent Claim
17 words
An arrangement as set forth in claim 6, wherein said regulator means comprise voltage-controlled monostable multivibrator means.
Claim 14
Dependent Claim
117 words
An arrangement as set forth in claim 6, wherein said conversion means comprise integrator means integrating said air intake signal and furnishing an integrated air intake signal; sampling means connected to the output of said integrator means for sampling said integrated air intake signal at a predetermined time in the operating cycle of said engine; and hold circuit means connected to the output of said sampling means for maintaining said so-sampled integrated intake signal between successive sampling times; and wherein said regulator means comprise voltage-controlled monostable multivibrator means connected to the output of said hold circuit means, and means switching said monostable multivibrator means into the unstable state in synchronism with the operation of said sampling means.
Claim 15
Dependent Claim
32 words
An arrangement as set forth in claim 13, wherein said integrator means comprise additional amplifier means having an output and integrator capacitor means connected to said output of said additional amplifier means.
Claim 16
Dependent Claim
32 words
An arrangement as set forth in claim 14, further comprising integrator shunting means operated in synchronism with said sampling means for shunting said integrator capacitor following each operation of said sampling means.
References Cited (Backward Citations)
US3051752A
Cited
US2941524A
Cited
US3326040A
Cited
US3460520A
Cited
US3425277A
Cited
US3575147A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |