US4715145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lock-up control for shockless gear shifting
Assignee: Nissan Motor Co Ltd
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Filing: 1985-05-31
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Granted: 1987-12-29
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Expires: 2005-05-31
Abstract
Abstract A lock-up control system for a lock-up type automatic transmission is disclosed where the transmission output torque is monitored and the interruption of the lock-up action is executed after the transmission output torque has satisfied a predetermined condition after generation of a command for shifting within the transmission.
Inventors
- 👤 Hitoshi Takeda
- 👤 Sadao Takase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:00
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
A lock-up control system for a lock-up type automatic transmission including a torque converter with a lock-up clutch, comprising: means for detecting the occurrence of a command for shifting the transmission and generating a shifting command signal; means for detecting output torque of the transmission and generating a transmission output torque signal indicative of the output torque of the transmission; and means for determining and storing signals indicative of variations in said output torque signal and interrupting the lock-up action of the torque converter based on said transmission output torque signal by releasing the engagement of the lock-up clutch after said transmission output torque signal has demonstrated a predetermined trend in said variations after generation of said shifting command signal.
Claim 2
Dependent Claim
120 words
A lock-up control system for a lock-up type automatic transmission including a torque converter with a lock-up clutch, comprising: means for detecting the occurrence of a command for shifting the transmission and generating a shifting command signal; means for detecting output torque of the transmission and generating a transmission output torque signal indicative of the output torque of the transmission; and means for determining and storing signals indicative of variations in said output torque signal and interrupting the lock-up action of the torque converter based on said transmission output torque signal by releasing the engagement of the lock-up clutch after said transmission output torque signal has demonstrated a predetermined trend in said variations after generation of said shifting command signal.
Claim 3
Dependent Claim
112 words
A lock-up control system as claimed in claim 1, wherein said lock-up action interrupting means comprises: means for determining a time derivative of said transmission output torque signal after generation of said shifting command signal and estimating a trend in the transmission output torque; means for generating a command signal for interrupting the lock-up action of the torque converter after said transmission output torque signal has satisfied a predetermined relationship with said estimated trend; and means for generating a command signal for releasing the interruption of the lock-up action after a second predetermined condition has been satisfied after generation of said command signal for interrupting the lock-up action of the torque converter.
Claim 4
Dependent Claim
38 words
A lock-up control system as claimed in claim 2, wherein said second predetermined condition involves the lapse of a predetermined period of time after generation of said command signal for interrupting the lock-up action of the torque converter.
Claim 5
Dependent Claim
33 words
A lock-up control system as claimed in claim 2, wherein said second predetermined condition involves a condition where the time derivative of said transmission output torque signal has fallen into a predetermined range.
Claim 6
Dependent Claim
106 words
A lock-up control method for a lock-up type automatic transmission including a torque converter with a lock-up clutch, comprising: detecting the occurrence of a command for shifting the transmission and generating a shifting command signal; detecting output torque of the transmission and generating a transmission output torque signal indicative of the output torque of the transmission; determining and storing signals indicative of variations in said output torque signal; and interrupting the lock-up action of the torque converter by releasing the engagement of the lock-up clutch after said transmission output torque signal has demonstrated a predetermined trend in said variations after generation of said shifting command signal.
Claim 7
Dependent Claim
106 words
A lock-up control method for a lock-up type automatic transmission including a torque converter with a lock-up clutch, comprising: detecting the occurrence of a command for shifting the transmission and generating a shifting command signal; detecting output torque of the transmission and generating a transmission output torque signal indicative of the output torque of the transmission; determining and storing signals indicative of variations in said output torque signal; and interrupting the lock-up action of the torque converter by releasing the engagement of the lock-up clutch after said transmission output torque signal has demonstrated a predetermined trend in said variations after generation of said shifting command signal.
Claim 8
Dependent Claim
106 words
A lock-up control method as claimed in claim 5, wherein said lock-up action interrupting step comprises: determining a time derivative of said transmission output torque signal after generation of said shifting command signal and estimating a trend in the transmission output torque; generating a command signal for interrupting the lock-up action of the torque converter after said transmission output torque signal has satisfied a predetermined relationship with said estimated trend; and generating a command signal for releasing the interruption of the lock-up action after a second predetermined condition has been satisfied after generation of said command signal for interrupting the lock-up action of the torque converter.
References Cited (Backward Citations)
US3293934A
Cited
US3602069A
Cited
US3683720A
Cited
US3752012A
Cited
US3818783A
Cited
US4051931A
Cited
US4105100A
Cited
US4090417A
Cited
US4270636A
Cited
US4220058A
Cited
US4507985A
Cited
US4431095A
Cited
US4457410A
Cited
US4539869A
Cited
US4476970A
Cited
JPS59170560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-12-28 | 1991-06-29 | 1991-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-28 | 1995-06-29 | 1995-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-28 | 1999-06-29 | 1999-12-29 | $7700.00 | Window Closed / Lapsed |