Patent US4715145A successfully refreshed from Google Patents.
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 11:56
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.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 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 |