EP0430675A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Continuously variable transmission with torque converter
Assignee: Subaru Corp
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Filing: 1990-11-28
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Granted: —
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Expires: 2010-11-28
Abstract
Abstract A continuously variable transmission has a torque converter with a lockup clutch. The lockup clutch is engaged in accordance with driving conditions of the torque converter. The necessary amount of downshift of the transmission is decided in dependency on the rate of change of speed of an input member of the transmission so that the speed of an input member coincides with speed of the engine. The transmission is downshifted by the necessary amount and the lockup clutch is engaged so as to change the engine speed at a substantially constant rate.
Inventors
- 👤 Keiji C/O Fuji Jukogyo Sato
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 22:47
CPC Classifications
B; B60; B60W; B60W10/00; B60W10/04; B60W10/06; B60W10/10; B60W10/101; B60W10/107; B60W30/00; B60W30/18; B60W30/1819; B60W30/19; F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H61/66; F16H61/662; F16H61/66254; F16H61/66259; F16H2061/6604; F16H2061/6608
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
188 words
A system for controlling a continuously variable transmission for a vehicle, and said transmission having a torque converter with a lockup clutch, the control system including a hydraulic circuit including a transmission ratio control valve and control valve means for controlling the oil supply to said transmission ratio control valve in order to change the transmission ratio; characterised by a lockup control valve arranged to be operated in accordance with driving conditions to engage said lockup clutch; deciding means for producing a lockup signal in accordance with the condition of the torque converter for actuating said lockup control valve; downshift control means responsive to said lockup signal for providing a downshift signal for said transmission in dependency on the rate of change of speed of an input member of the transmission so that the speed of the input member coincides with the speed of said engine; and actuating means responsive to said lockup signal for operating said control valve and said lockup control valve so as to downshift said transmission and to engage the lockup clutch so as to change the engine speed at a substantially constant rate.
Claim 2
Dependent Claim
36 words
A control system according to claim 1, wherein said deciding means produces the lockup signal when speed ratio of an output member of said torque converter to an input member becomes larger than a predetermined value.
Claim 3
Dependent Claim
36 words
A control system according to claim 1, wherein said downshift quantity providing means decides the downshift quantity in accordance with changing rate of the engine speed and changing rate of drive pulley speed of said transmission.
References Cited (Backward Citations)
No citation records indexed.
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