Patent US4846021A successfully refreshed from Google Patents.
US4846021A
Expired / Lapsed
US
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System for shift control in automatic transmission
Assignee: Toyota Motor Corp
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Filing: 1987-02-17
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Granted: 1989-07-11
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Expires: 2007-02-17
Abstract
Abstract In a system for shift control in an automatic transmission, wherein a hydraulic control device is operated to selectively switch the engagements of frictionally engaging devices and any one of plurality of gear stages can be achieved in accordance with a preset shift map, a system is provided to judge whether shifting is abnormal or not. When it is judged that the shifting is abnormal, oil pressure for engaging the frictionally engaging devices is raised. With this arrangement, the durability of the frictionally engaging devices can be secured.
Inventors
- 👤 Yukio Hamano
- 👤 Fumiaki Izumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:41
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/12; B; B60; B60W; B60W10/00; B60W10/04; B60W10/10; B60W10/11; B60W30/00; B60W30/18; B60W30/1819; F16H61/04; F16H61/06; F16H61/061; F16H2061/1208; F16H2061/1216; F16H2061/1224; F16H2061/1256; F16H2061/126; F16H2061/1264; F16H2061/1276; F16H2061/1284; F16H2306/00; F16H2306/40; F16H2306/42; F16H61/0021; F16H61/08; F16H63/00; F16H63/40; F16H63/50; F16H63/502
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
167 words
A system for integrally controlling an automatic transmission and an engine, wherein gear shifting mechanisms and a plurality of frictionally engaging devices are provided, a hydraulic control device is operated to selectively switch engagements of said frictionally engaging devices, and any one of a plurality of gear stages can be achieved in accordance with a preset shift map, and means for changing torque of said engine is provided, said torque of the engine is changed during said switching of the engagements of the frictionally engaging devices, the frictionally engaging devices being actuated by an increase of hydraulic pressure by an amount, said system comprising: means for judging whether or not said switching of the engagements deviates from a preset schedule due to failure of said engine torque change; means for raising said amount when said switching of engagements is judged to deviate from the preset schedule, said raising of the amount of hydraulic pressure is performed while said judged switching of the engagements itself is still performed.
Claim 2
Independent Claim
167 words
A system for integrally controlling an automatic transmission and an engine, wherein gear shifting mechanisms and a plurality of frictionally engaging devices are provided, a hydraulic control device is operated to selectively switch engagements of said frictionally engaging devices, and any one of a plurality of gear stages can be achieved in accordance with a preset shift map, and means for changing torque of said engine is provided, said torque of the engine is changed during said switching of the engagements of the frictionally engaging devices, the frictionally engaging devices being actuated by an increase of hydraulic pressure by an amount, said system comprising: means for judging whether or not said switching of the engagements deviates from a preset schedule due to failure of said engine torque change; means for raising said amount when said switching of engagements is judged to deviate from the preset schedule, said raising of the amount of hydraulic pressure is performed while said judged switching of the engagements itself is still performed.
Claim 3
Dependent Claim
23 words
A system for shift control as set forth in claim 1, further comprising: means for issuing a warning when said amount is raised.
Claim 4
Dependent Claim
34 words
A system for shift control as set forth in claim 15, further comprising: means for detecting shift transitional time; wherein the raising of said amount is carried out only for the shift transitional time.
Claim 5
Dependent Claim
44 words
A system for shift control as set forth in claim 1, further comprising; means for determining a predetermined time duration including a shift transitional time; wherein the raising of amount is carried out only for the predetermined time duration including the shift transitional time.
Claim 6
Dependent Claim
38 words
A system for shift control as set forth in claim 1, further comprising: means for detecting engine load: wherein the raising of said amount is carried out only when the engine load 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) | 1992-07-10 | 1993-01-09 | 1993-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-10 | 1997-01-09 | 1997-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-10 | 2001-01-09 | 2001-07-11 | $7700.00 | Window Closed / Lapsed |