US4794898A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for engine idle speed control
Assignee: Denso Corp
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Filing: 1988-02-29
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Granted: 1989-01-03
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Expires: 2008-02-29
Abstract
Abstract In a battery charging system for an automobile, the conduction rate of a switching circuit which controls field current of the generator is detected, while engine speed is also detected. Since the conduction rate represents the actual amount of electricity generated by the generator, the conduction rate as well as engine speed is used to determine optimal engine idle speed. To this end desired conduction rate values for various engine speeds within idle speed range are prestored in a memory, and a desired conduction rate is read out using detected engine speed so that a detected conduction rate will be compared with the desired conduction rate. Using the result of comparisonn, idle speed is either increased or decreased so that the actual conduction rate approaches the desired conduction rate. In one embodiment, the generator is disabled when the actual conduction rate is greater than the desired conduction rate in order to prevent engine stall.
Inventors
- 👤 Hidetoshi Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:50
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/14; H02J7/1446; F; F02; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/08; F02D41/083
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
179 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at a least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function of conduction rate of said switching means; (c) second means for detecting second data which is a function of the rotational speed of said engine or said generator; (d) computing means responsive to the detected first data received from said first means and responsive to the detected second data received from said second means for: deriving a reference which is determined as a function of a desired conduction rate of said switching means, corresponding to said second data, from said computing means; comparing said detected first data with the reference; producing a control signal in accordance with the results of the comparison; and (e) idle speed control means responsive to said control signal for controlling the rotational speed of said engine, so that the detected first data approaches the reference.
Claim 2
Dependent Claim
179 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at a least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function of conduction rate of said switching means; (c) second means for detecting second data which is a function of the rotational speed of said engine or said generator; (d) computing means responsive to the detected first data received from said first means and responsive to the detected second data received from said second means for: deriving a reference which is determined as a function of a desired conduction rate of said switching means, corresponding to said second data, from said computing means; comparing said detected first data with the reference; producing a control signal in accordance with the results of the comparison; and (e) idle speed control means responsive to said control signal for controlling the rotational speed of said engine, so that the detected first data approaches the reference.
Claim 3
Dependent Claim
51 words
An engine idle speed control apparatus as claimed in claim 1, further comprising means responsive to said computing means for controlling said switching means in such a manner that the current flowing through said field coil of said generator is increased when said detected first data is higher than said reference.
Claim 4
Dependent Claim
72 words
An engine idle speed control apparatus as claimed in claim 2, wherein said means for controlling said switching means comprises means for deriving an engine speed data corresponding to said detected first data and for controlling said switching means to substantially decrease the current flowing through said field coil of said generator until said rotational speed of said engine becomes equal to said engine speed data corresponding to said detected first data.
Claim 5
Dependent Claim
187 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function conduction rate of said switching means; (c) second means for detecting second data which is a function of the rotational speed of said engine or said generator; (d) computing means responsive to said detected first data received from said first means to said detected second data received from said second means for: determining a reference which is a function of a desired conduction rate of said switching means on the basis of said detected speed of said engine or said second data from said computing means; and (e) idle speed control means for changing the rotational speed of said engine or said generator, in such a manner that the rotational speed thereof is increased when said reference is lower than said detected first data, and the rotational speed is decreased when reference is higher than said detected first data.
Claim 6
Dependent Claim
187 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function conduction rate of said switching means; (c) second means for detecting second data which is a function of the rotational speed of said engine or said generator; (d) computing means responsive to said detected first data received from said first means to said detected second data received from said second means for: determining a reference which is a function of a desired conduction rate of said switching means on the basis of said detected speed of said engine or said second data from said computing means; and (e) idle speed control means for changing the rotational speed of said engine or said generator, in such a manner that the rotational speed thereof is increased when said reference is lower than said detected first data, and the rotational speed is decreased when reference is higher than said detected first data.
Claim 7
Dependent Claim
38 words
An engine idle speed control apparatus as claimed in claim 4, wherein said first means comprises a comparator responsive to a voltage across said field coil, and a smoothing circuit responsive to an output signal from said comparator.
Claim 8
Dependent Claim
41 words
An engine idle speed control apparatus as claimed in claim 4, wherein said second means comprises a comparator responsive to a voltage from an armature coil of said generator, and a frequency-to-voltage convertor responsive to an output signal from said comparator.
Claim 9
Dependent Claim
51 words
An engine idle speed control apparatus as claimed in claim 4, further comprising means responsive to said computing means for controlling said switching means in such a manner that the current flowing through said field coil of said generator is increased when said detected first data is higher than said reference.
Claim 10
Dependent Claim
72 words
An engine idle speed control apparatus as claimed in claim 7, wherein said means for controlling said switching means comprises means for driving an engine speed data corresponding to said detected first data and for controlling said switching means to substantially decrease the current flowing through said field coil of said generator until said rotational speed of said engine becomes equal to said engine speed data corresponding to said detected first data.
Claim 11
Independent Claim
162 words
A method for controlling idle speed of an engine of an automobile having an engine driven generator, comprising the steps of: (a) detecting generated voltage form said generator; (b) controlling the amount of electricity generated by said generator by way of a switching circuit in accordance with the detected voltage; (c) detecting conduction rate of said switching circuit; (d) detecting the rotational speed of any one of said engine and said generator; (e) deriving a desired conduction rate of said switching circuit corresponding to said detected rotational speed of any one of said engine and said generator; (f) comparing said detected conduction rate of said switching circuit with said desired conduction rate thereof; (g) producing a control signal in accordance with the results of the comparison; and (h) controlling the rotational speed of said engine, in response to said control signal, wherein the rotational speed of said engine is increased when said desired conduction rate is lower than said detected conduction rate.
Claim 12
Independent Claim
162 words
A method for controlling idle speed of an engine of an automobile having an engine driven generator, comprising the steps of: (a) detecting generated voltage form said generator; (b) controlling the amount of electricity generated by said generator by way of a switching circuit in accordance with the detected voltage; (c) detecting conduction rate of said switching circuit; (d) detecting the rotational speed of any one of said engine and said generator; (e) deriving a desired conduction rate of said switching circuit corresponding to said detected rotational speed of any one of said engine and said generator; (f) comparing said detected conduction rate of said switching circuit with said desired conduction rate thereof; (g) producing a control signal in accordance with the results of the comparison; and (h) controlling the rotational speed of said engine, in response to said control signal, wherein the rotational speed of said engine is increased when said desired conduction rate is lower than said detected conduction rate.
Claim 13
Independent Claim
157 words
A method of controlling idle speed of an engine of an automobile having an engine driven generator, comprising the steps of: (a) detecting generated voltage from said generator; (b) controlling the amount of electricity generated by said generator by way of a switching circuit in accordance with the detected voltage; (c) detecting first data which is a function of conduction rate of said switching circuit; (d) detecting second data which is a function of the rotational speed of any one of said engine and said generator; (e) determining a reference which is a function of a desired conduction rate of said switching circuit on the basis of said second data and (f) controlling said idle speed for changing the rotational speed of said engine, wherein the rotation al speed is increased when said reference is lower than said detected first data, and the rotational speed is decreased when said reference is higher than said detected first data.
Claim 14
Independent Claim
157 words
A method of controlling idle speed of an engine of an automobile having an engine driven generator, comprising the steps of: (a) detecting generated voltage from said generator; (b) controlling the amount of electricity generated by said generator by way of a switching circuit in accordance with the detected voltage; (c) detecting first data which is a function of conduction rate of said switching circuit; (d) detecting second data which is a function of the rotational speed of any one of said engine and said generator; (e) determining a reference which is a function of a desired conduction rate of said switching circuit on the basis of said second data and (f) controlling said idle speed for changing the rotational speed of said engine, wherein the rotation al speed is increased when said reference is lower than said detected first data, and the rotational speed is decreased when said reference is higher than said detected first data.
Claim 15
Dependent Claim
37 words
A method of controlling idle speed as claimed in claim 10, further comprising the step of substantially disabling said generator when said desired conduction rate of said switching circuit is lower than said detected conduction rate thereof.
Claim 16
Dependent Claim
130 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function of conduction rate of said switching means; (c) second means for detecting second data which is a function of a rotational speed of said engine; (d) third means for deriving a desired relationship between said first data and said second data; and (e) idle speed control means for controlling the rotational speed of said engine in such a manner that a relationship between the detected first data and the detected second data approaches said desired relationship therebetween derived in said third means.
Claim 17
Dependent Claim
130 words
An engine idle speed control apparatus for use with an engine driven generator of an automobile having at least a field coil, comprising: (a) switching means for controlling current flowing through said field coil of said generator; (b) first means for detecting first data which is a function of conduction rate of said switching means; (c) second means for detecting second data which is a function of a rotational speed of said engine; (d) third means for deriving a desired relationship between said first data and said second data; and (e) idle speed control means for controlling the rotational speed of said engine in such a manner that a relationship between the detected first data and the detected second data approaches said desired relationship therebetween derived in said third means.
Claim 18
Dependent Claim
46 words
An engine idle speed control apparatus as claimed in claim 12, further comprising means for controlling said switching means in such a manner that the current flowing through said field coil of said generator is increased when said detected first data is higher than said reference.
Claim 19
Dependent Claim
72 words
An engine idle speed control apparatus as claimed in claim 13, wherein said means for controlling said switching means comprises means for deriving an engine speed data corresponding to said detected first data and for controlling said switching means to substantially decrease the current flowing through said field coil of said generator until said rotational speed of said engine becomes equal to said engine speed data corresponding to said detected first data.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-03 | 1992-07-04 | 1993-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-03 | 1996-07-04 | 1997-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-03 | 2000-07-04 | 2001-01-03 | $7700.00 | Window Closed / Lapsed |