Patent US5697479A successfully refreshed from Google Patents.
US5697479A
Expired / Lapsed
US
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Slip control apparatus for motor vehicle lock-up clutch
Assignee: Toyota Motor Corp
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Filing: 1996-12-10
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Granted: 1997-12-16
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Expires: 2016-12-10
Abstract
Abstract An apparatus including a slip control device for controlling an amount of slip of a lock-up clutch disposed between pump and turbine impellers in a power transmission system of a motor vehicle, such that an actual slip speed of the lock-up clutch coincides with a target slip speed, the apparatus comprising a hunting detecting device for determining the presence of a hunting defect if an amplitude of variation of the engine speed is larger than a predetermined first reference while an amplitude of variation of the turbine speed is not larger than a predetermined second reference.
Inventors
- 👤 Katsumi Kono
- 👤 Shinya Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:51
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H59/00; F16H59/36; F16H59/38; F16H2059/385; F16H59/46; F16H2059/465; F16H2059/467; F16H61/12; F16H2061/1208; F16H2061/145; Y; Y10; Y10S; Y10S477/00; Y10S477/906
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
190 words
An apparatus including slip control means for controlling an amount of slip of a lock-up clutch disposed between a pump impeller and a turbine impeller in a power transmission system of a motor vehicle, such that an actual slip speed of said lock-up clutch coincides with a target slip speed, said apparatus comprising: engine speed variation determining means for determining whether an amplitude of variation of a speed of an engine of the vehicle connected to said pump impeller is larger than a predetermined first reference; turbine speed variation determining means for determining whether an amplitude of variation of a speed of said turbine impeller is larger than a predetermined second reference; and hunting detecting means for determining the presence of a hunting defect in slip control of said lock-up clutch by said slip control means, if said engine speed variation determining means determines that said amplitude of variation of the speed of said engine is larger than said predetermined first reference while said turbine speed variation determining means determines that said amplitude of variation of the speed of said turbine impeller is not larger than said predetermined second reference.
Claim 2
Independent Claim
190 words
An apparatus including slip control means for controlling an amount of slip of a lock-up clutch disposed between a pump impeller and a turbine impeller in a power transmission system of a motor vehicle, such that an actual slip speed of said lock-up clutch coincides with a target slip speed, said apparatus comprising: engine speed variation determining means for determining whether an amplitude of variation of a speed of an engine of the vehicle connected to said pump impeller is larger than a predetermined first reference; turbine speed variation determining means for determining whether an amplitude of variation of a speed of said turbine impeller is larger than a predetermined second reference; and hunting detecting means for determining the presence of a hunting defect in slip control of said lock-up clutch by said slip control means, if said engine speed variation determining means determines that said amplitude of variation of the speed of said engine is larger than said predetermined first reference while said turbine speed variation determining means determines that said amplitude of variation of the speed of said turbine impeller is not larger than said predetermined second reference.
Claim 3
Dependent Claim
72 words
An apparatus according to claim 1, wherein said turbine speed variation determining means comprises turbine speed obtaining means for obtaining the speed of said turbine impeller, slip speed obtaining means for obtaining said actual slip speed of said lock-up clutch, and variation determining means for determining whether an amplitude of variation of a sum of said speed of said turbine impeller and said actual slip speed is larger than a predetermined value.
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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) | 2000-12-15 | 2001-06-16 | 2001-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-15 | 2005-06-16 | 2005-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-15 | 2009-06-16 | 2009-12-16 | $7700.00 | Window Closed / Lapsed |