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US4688534A Expired / Lapsed US ⏱️ 0.0 years remaining

Idling speed control device of an internal combustion engine

Assignee: Toyota Motor Corp
•
Filing: 1986-08-04
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Granted: 1987-08-25
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Expires: 2006-08-04
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Abstract

Abstract An idling speed control device in an internal combustion engine comprising an idling speed control valve arranged in a bypass bypassing the throttle valve of the engine. The valve is fully opened at the start of the engine and closed to a controlled rate when the revolutional speed of the engine reaches a reference rotational value. At least two reference rotational values are provided depending upon a temperature; one of which is a higher value for the considerably high temperature, and the other is a low value for a normal temperature.

Inventors

  • 👤 Yuji Takeda
  • 👤 Katsushi Anzai
  • 👤 Osamu Harada
  • 👤 Toshio Suematsu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 11:09
CPC Classifications
F; F02; F02D; F02D31/00; F02D31/001; F02D31/002; F02D31/003; F02D31/005; F02D41/00; F02D41/02; F02D41/04; F02D41/06; F02D41/061; F02D11/00; F02D11/06; F02D11/10; F02D2011/101; F02D2011/102

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 180 words
An idling speed control device of an internal combustion engine, comprising: a first detecting means for detecting a revolutional speed of said engine; a second detecting means for detecting a temperature of said engine; means for regulating an amount of intake air during idling of said engine; means for providing at least two reference rotational values including a first predetermined rotational value when the temperature of said engine is higher than a predetermined temperature value in a considerably higher range, and a second predetermined rotational value when the temperature of said engine is lower than said predetermined temperature value, the first predetermined rotational value being greater than the second predetermined rotational value; and means responsive to outputs of said first and second detecting means for controlling said regulating means to cause said amount of intake air to be increased to a predetermined maximum value when said engine is started, and subsequently, to be decreased from said predetermined maximum value to a controlled value when the revolutional speed of said engine reaches the reference rotational value after the engine has started.
Claim 2
Dependent Claim 180 words
An idling speed control device of an internal combustion engine, comprising: a first detecting means for detecting a revolutional speed of said engine; a second detecting means for detecting a temperature of said engine; means for regulating an amount of intake air during idling of said engine; means for providing at least two reference rotational values including a first predetermined rotational value when the temperature of said engine is higher than a predetermined temperature value in a considerably higher range, and a second predetermined rotational value when the temperature of said engine is lower than said predetermined temperature value, the first predetermined rotational value being greater than the second predetermined rotational value; and means responsive to outputs of said first and second detecting means for controlling said regulating means to cause said amount of intake air to be increased to a predetermined maximum value when said engine is started, and subsequently, to be decreased from said predetermined maximum value to a controlled value when the revolutional speed of said engine reaches the reference rotational value after the engine has started.
Claim 3
Dependent Claim 57 words
An idling speed control device according to claim 1, wherein said engine has an intake air passage having a throttle valve arranged therein, and said means for regulating the amount of intake air during idling of said engine comprises a bypass air passage bypassing said throttle valve, and a valve means arranged in said bypass air passage.
Claim 4
Dependent Claim 27 words
An idling speed control device according to claim 2, wherein said valve means includes a valve element and an electric step motor for operating said valve element.
Claim 5
Dependent Claim 17 words
An idling speed control device according to claim 2, wherein said valve means comprises a solenoid-operated valve.
Claim 6
Dependent Claim 61 words
An idling speed control device according to claim 2, wherein said means for providing at least two reference rotational values further provides a third predetermined rotational value when the temperature of said engine is lower than a second predetermined temperature value lower than said first predetermined temperature value, the third predetermined rotational value being greater than the second predetermined rotational value.
Claim 7
Dependent Claim 23 words
An idling speed control device according to claim 5, wherein the first predetermined rotational value is greater than the third predetermined rotational value.
Claim 8
Dependent Claim 25 words
An idling speed control device according to claim 6, wherein said first, second, and third predetermined rotational values are 1000, 500, and 800 rpm, respectively.
Claim 9
Dependent Claim 20 words
An idling speed control device according to claim 7, wherein said third predetermined rotational value increases as the temperature decreases.
Claim 10
Dependent Claim 28 words
An idling speed control device according to claim 2, wherein said second detecting means comprises a temperature sensor for detecting a temperature of cooling water of the engine.
Claim 11
Dependent Claim 20 words
An idling speed control device according to claim 9, wherein said first predetermined temperature value is higher than 100° C.
Claim 12
Dependent Claim 59 words
An idling speed control device according to claim 9, wherein said device further comprises a temperature sensor for detecting a temperature of the intake air, and said first predetermined rotational value is selected when the temperature of the cooling water is higher than a first value and the temperature of the intake air is higher than a second value.
Claim 13
Dependent Claim 23 words
An idling speed control device according to claim 11, wherein said first value is 110° C. and said second value is 70° C.
Claim 14
Dependent Claim 68 words
An idling speed control device according to claim 2, wherein a learning value is used for determining said controlled value when the revolutional speed of the engine reaches the reference rotational value, said learning value being determined by an opening value of said valve means when the idling speed is between predetermined higher and a lower limits during previous running of the engine before the engine is restarted.
Claim 15
Dependent Claim 60 words
An idling speed control device according to claim 2, wherein said device further comprises a fuel supply means which supplies an increased amount of fuel when the temperature of said engine is higher than said predetermined temperature value, and does not supply an increased amount of fuel when the temperature of said engine is lower than said predetermined temperature value.

References Cited (Backward Citations)

US4191051A Cited
JPS5681230A Cited
US4414943A Cited
US4444168A Cited
US4484552A Cited
US4479471A Cited
JPS59162338A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-08-24 1991-02-23 1991-08-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-08-24 1995-02-23 1995-08-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-08-24 1999-02-23 1999-08-25 $7700.00 Window Closed / Lapsed

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