US4890590A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe method and apparatus for internal combustion engines
Assignee: Denso Corp
•
Filing: 1988-11-15
•
Granted: 1990-01-02
•
Expires: 2008-11-15
Abstract
Abstract In an engine control system which determines the amount of fuel to be injected on the basis of an intake pipe pressure detected downstream of a throttle valve and engine speed (D-EFI), fail-safe action is provided when a failure of an intake pipe on the downstream side of the throttle valve is detected. The fail-safe apparatus of the present invention is designed to signal the occurrence of an abnormality with the intake system when the throttle valve is not being opened, that is, the throttle valve is stationary or is closing, a vehicle speed variation exceeds its specific value and the engine speed exceeds its specific value. When these conditions are detected, engine power is controlled lower, thereby assuring vehicle driving safety.
Inventors
- 👤 Shinichi Iwamoto
- 👤 Shigenori Isomura
- 👤 Mitsunori Takao
- 👤 Kenichiro Kamai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:25
CPC Classifications
F; F02; F02D; F02D17/00; F02D17/04; F02B; F02B77/00; F02B77/08; F02B77/088; F02D41/00; F02D41/22; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
153 words
Apparatus for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve, said engine being controlled on the basis of intake air pressure and engine speed, said apparatus comprising: first means for detecting a position of said throttle valve and non-opening of said throttle valve on the basis of said position; second means for detecting a speed of said engine and determining when a value related to engine speed exceeds a predetermined criterion based upon said speed; judging means, coupled to said first and second means, for judging abnormal operation of said intake system when said first means detects that said throttle valve is not opening and said second means detects that said value related to engine speed exceeds said predetermined criterion; and power decreasing means for decreasing engine power on the basis of a result of a judgement by said judging means.
Claim 2
Dependent Claim
153 words
Apparatus for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve, said engine being controlled on the basis of intake air pressure and engine speed, said apparatus comprising: first means for detecting a position of said throttle valve and non-opening of said throttle valve on the basis of said position; second means for detecting a speed of said engine and determining when a value related to engine speed exceeds a predetermined criterion based upon said speed; judging means, coupled to said first and second means, for judging abnormal operation of said intake system when said first means detects that said throttle valve is not opening and said second means detects that said value related to engine speed exceeds said predetermined criterion; and power decreasing means for decreasing engine power on the basis of a result of a judgement by said judging means.
Claim 3
Dependent Claim
33 words
Apparatus as in claim 1, wherein said judging means also generates said value in accordance with variations in engine speed detected by said second means and performs said judging based on said variations.
Claim 4
Dependent Claim
40 words
Apparatus as in claim 2, wherein said second means detects said engine speed variation over a specific period of time and said judging means judges abnormal operation when said variation over a specific period of time exceeds said predetermined criterion.
Claim 5
Dependent Claim
24 words
Apparatus as in claim 1, wherein said first means detects said non-opening when a variation in said throttle valve position is zero or negative.
Claim 6
Dependent Claim
23 words
Apparatus as in claim 1, wherein said first means includes a switch which detects that said throttle valve is in a fully-closed position.
Claim 7
Dependent Claim
31 words
Apparatus as in claim 1 further comprising warning means for warning a driver of abnormal operation of said intake system when said judging means has judged the occurrence of the abnormality.
Claim 8
Dependent Claim
25 words
Apparatus as in claim 1, wherein said judging means also changes said predetermined criterion on the basis of an on-off operation of a brake switch.
Claim 9
Dependent Claim
19 words
Apparatus as in claim 1, wherein said judging means changes said predetermined criterion in accordance with brake oil pressure.
Claim 10
Dependent Claim
20 words
Apparatus as in claim 1, wherein said power decreasing means decreases an engine speed above which fuel is automatically reduced.
Claim 11
Dependent Claim
199 words
Apparatus for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve, said engine being controlled on the basis of intake air pressure and engine speed, said apparatus comprising: first means for detecting a position of said throttle valve; second means for detecting a speed of said engine; third means for detecting a parameter of said vehicle other than said throttle valve position and said engine speed; judging means, coupled to said first, second and third means, for discerning, in response to said throttle valve position, whether said throttle valve is not opening, discerning in response to said engine speed whether a valve associated with engine speed exceeds a predetermined criterion, discerning in response to said parameter whether a change in said parameter exceeds a second predetermined criterion and judging abnormal operation of said intake system when it is determined that said throttle valve is not opening, said value related to engine speed exceeds said predetermined criterion and said change in said parameter exceeds said second predetermined criterion; and power decreasing means for decreasing engine power on the basis of a result of a judgement by said judging means.
Claim 12
Dependent Claim
199 words
Apparatus for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve, said engine being controlled on the basis of intake air pressure and engine speed, said apparatus comprising: first means for detecting a position of said throttle valve; second means for detecting a speed of said engine; third means for detecting a parameter of said vehicle other than said throttle valve position and said engine speed; judging means, coupled to said first, second and third means, for discerning, in response to said throttle valve position, whether said throttle valve is not opening, discerning in response to said engine speed whether a valve associated with engine speed exceeds a predetermined criterion, discerning in response to said parameter whether a change in said parameter exceeds a second predetermined criterion and judging abnormal operation of said intake system when it is determined that said throttle valve is not opening, said value related to engine speed exceeds said predetermined criterion and said change in said parameter exceeds said second predetermined criterion; and power decreasing means for decreasing engine power on the basis of a result of a judgement by said judging means.
Claim 13
Dependent Claim
22 words
A fail-safe apparatus as in claim 10, wherein said third means includes means for detecting a speed of said motor vehicle .
Claim 14
Dependent Claim
38 words
A fail-safe apparatus as in claim 10, wherein said judging means determines variations in vehicle speed per specific period of time and judges abnormal operation when said variations per specific period of time exceed said second predetermined criterion.
Claim 15
Dependent Claim
24 words
Apparatus as in claim 12, wherein said judging means changes said second criterion on the basis of an ON-OFF operation of a brake switch.
Claim 16
Dependent Claim
19 words
Apparatus as in claim 12, wherein said judging means changes said second criterion in accordance with brake oil pressure.
Claim 17
Dependent Claim
20 words
Apparatus as in claim 10, wherein said power decreasing means decreases an engine speed above which fuel is automatically reduced.
Claim 18
Independent Claim
97 words
A method for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve which is controlled on the basis of intake air pressure and engine speed, said fail-safe method including the steps of: detecting a position of said throttle valve; detecting a speed of said engine; generating an abnormality signal indicating that said intake system is operating abnormally when said throttle valve is not opening and a value related to engine speed exceeds a predetermined criterion; and automatically decreasing engine power when said abnormality signal is generated.
Claim 19
Independent Claim
97 words
A method for preventing uncontrolled acceleration in an engine for a motor vehicle, said engine having an intake system with a throttle valve which is controlled on the basis of intake air pressure and engine speed, said fail-safe method including the steps of: detecting a position of said throttle valve; detecting a speed of said engine; generating an abnormality signal indicating that said intake system is operating abnormally when said throttle valve is not opening and a value related to engine speed exceeds a predetermined criterion; and automatically decreasing engine power when said abnormality signal is generated.
Claim 20
Dependent Claim
24 words
A method as in claim 16, wherein said decreasing step includes the step of decreasing an engine speed above which fuel is automatically reduced.
Claim 21
Dependent Claim
41 words
A method as in claim 16 further comprising the step of determining variations in engine speed over a predetermined time as said value related to engine speed, said generating step generating said abnormality signal when said variations exceed said predetermined criterion.
Claim 22
Dependent Claim
36 words
A method as in claim 18 further comprising the step of determining variations in vehicle speed over a predetermined time, said generating step generating said abnormality signal when said vehicle speed variations exceed another predetermined criterion.
Claim 23
Dependent Claim
35 words
A method as in claim 16 further comprising the step of detecting a speed of said vehicle, said generating step generating said abnormality signal when a value related to vehicle speed exceeds another predetermined criterion.
Claim 24
Dependent Claim
26 words
A method as in claim 20 further comprising the step of changing said another predetermined criterion in response to an ON-OFF state of a brake switch.
Claim 25
Dependent Claim
22 words
A method as in claim 20 further comprising the step of changing said another predetermined criterion in response to brake oil pressure.
Claim 26
Dependent Claim
25 words
A method as in claim 16 further comprising the step of changing said predetermined criterion in response to an ON-OFF state of a brake switch.
Claim 27
Dependent Claim
21 words
A method as in claim 16 further comprising the step of changing said predetermined criterion in response to brake oil pressure.
References Cited (Backward Citations)
US4269156A
Cited
JPS5749035A
Cited
US4685435A
Cited
JPS5752843A
Cited
JPS58176434A
Cited
US4562801A
Cited
JPS62103446A
Cited
US4748955A
Cited
US4641618A
Cited
US4785785A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-01 | 1993-07-03 | 1994-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-01 | 1997-07-03 | 1998-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-01 | 2001-07-03 | 2002-01-02 | $7700.00 | Window Closed / Lapsed |