US5332073A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for and method of controlling lockup clutch
Assignee: JATCO Ltd
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Filing: 1993-01-08
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Granted: 1994-07-26
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Expires: 2013-01-08
Abstract
Abstract A control system for a lockup clutch measures an actual time required from start of engagement of the lockup clutch until completion of engagement of the lockup clutch, and sets a reference time required from start of engagement of the lockup clutch until completion of engagement of the lockup clutch. The system modifies a change rate of the duty ratio to the time so as to reduce a difference between the actual time and the reference time.
Inventors
- 👤 Naonori Iizuka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:13
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H59/00; F16H59/36; F16H59/46; F16H2059/465; F16H2059/467; F16H61/02; F16H61/0202; F16H61/0251; F16H2061/0255; F16H59/14; F16H59/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
164 words
A method of controlling a lockup clutch, the lockup clutch allowing connection of a pump impeller side with a turbine runner side in a hydraulic power transmission, the lockup clutch being controlled by a solenoid having a duty ratio which, upon engagement of the lockup clutch, is changed continuously and in accordance with a time by a control means, the method comprising the steps of: measuring an actual time required from a start of engagement of the lockup clutch until a completion of engagement of the lockup clutch and generating an actual time indicative signal indicative of said actual time measured; setting a reference time required from said start of engagement of the lockup clutch until said completion of engagement of the lockup clutch and generating a reference time indicative signal indicative of said reference time set; and modifying a change rate of the duty ratio so as to reduce a difference between said actual time indicative signal and said reference time indicative signal.
Claim 2
Independent Claim
164 words
A method of controlling a lockup clutch, the lockup clutch allowing connection of a pump impeller side with a turbine runner side in a hydraulic power transmission, the lockup clutch being controlled by a solenoid having a duty ratio which, upon engagement of the lockup clutch, is changed continuously and in accordance with a time by a control means, the method comprising the steps of: measuring an actual time required from a start of engagement of the lockup clutch until a completion of engagement of the lockup clutch and generating an actual time indicative signal indicative of said actual time measured; setting a reference time required from said start of engagement of the lockup clutch until said completion of engagement of the lockup clutch and generating a reference time indicative signal indicative of said reference time set; and modifying a change rate of the duty ratio so as to reduce a difference between said actual time indicative signal and said reference time indicative signal.
Claim 3
Dependent Claim
28 words
A method as claimed in claim 1, wherein said reference time is determined by at least one of an oil temperature, a vehicular speed, and an engine load.
Claim 4
Independent Claim
168 words
A system for controlling a lockup clutch, the lockup clutch allowing connection of a pump impeller side with a turbine runner side in a hydraulic power transmission, the lockup clutch being controlled by a solenoid having a duty ratio which, upon engagement of the lockup clutch, is changed continuously and in accordance with a time by a control means, the control system comprising: means for measuring an actual time required from a start of engagement of the lockup clutch until a completion of engagement of the lockup clutch and generating an actual time indicative signal indicative of said actual time measured; means for setting a reference time required from said start of engagement of the lockup clutch until said completion of engagement of the lockup clutch and generating a reference time indicative signal indicative of said reference time set; and means for modifying a change rate of the duty ratio so as to reduce a difference between said actual time indicative signal and said reference time indicative signal.
Claim 5
Independent Claim
168 words
A system for controlling a lockup clutch, the lockup clutch allowing connection of a pump impeller side with a turbine runner side in a hydraulic power transmission, the lockup clutch being controlled by a solenoid having a duty ratio which, upon engagement of the lockup clutch, is changed continuously and in accordance with a time by a control means, the control system comprising: means for measuring an actual time required from a start of engagement of the lockup clutch until a completion of engagement of the lockup clutch and generating an actual time indicative signal indicative of said actual time measured; means for setting a reference time required from said start of engagement of the lockup clutch until said completion of engagement of the lockup clutch and generating a reference time indicative signal indicative of said reference time set; and means for modifying a change rate of the duty ratio so as to reduce a difference between said actual time indicative signal and said reference time indicative signal.
Claim 6
Dependent Claim
28 words
A system as claimed in claim 3, wherein said reference time is determined by at least one of an oil temperature, a vehicular speed, and an engine load.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-25 | 1998-01-24 | 1998-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-25 | 2002-01-24 | 2002-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-25 | 2006-01-24 | 2006-07-26 | $7700.00 | Window Closed / Lapsed |