EP0323618A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Line pressure control system for automatic transmission
Assignee: Nissan Motor Co Ltd
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Filing: 1988-12-23
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Granted: —
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Expires: 2008-12-23
Abstract
Abstract A line pressure (P L ) is adjusted based on data which are updated after evaluation of an intertia phase time of a previous shifting in comparison with a predetermined value. Thus, during the next shifting of the same kind, a shifting friction device is engaged by the line pressure (P L ) which has been properly adjusted, thus assuring shock-free shifting irrespectively of manufacturing variations and/or degradation with time of component parts.
Inventors
- 👤 Hiroshi Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 14:20
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/04; F16H61/0437; F16H61/0021; F16H2061/0075; F16H2061/0087; F16H2061/0096; F16H61/02; F16H61/0202; F16H61/0251; F16H2061/0255; F16H61/68; F16H61/684
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
218 words
A line pressure control system for an automatic transmission including a transmission input member and a transmission output member, the automatic transmission being shiftable between two gear ratios and including a friction device whcih is adpated to be engaged in response to a magnitude of a line pressure to effect a shifting between the two gear ratios, the line pressure control system, comprising: input sensor means for detecting a revolution speed of the transmission input member and generating a first sensor output signal indicative of said revolution speed of the transmission input member detected; output sensor means for detecting a revolution speed of the transmission output member and generating a second sensor output signal indicative of said revolution speed of the transmission output member detected; means responsive to said first and second sensor output signals for determining a gear ratio of said revolution speed of the transmission input member to said revolution speed of the transmission output member; means for measuring an inertia phase time when said gear ratio varies within a predetermined range during the shifting; means for adjusting the magnitude of the line pressure which the friction device is engaged on during the next occurrence of the shifting in such a manner as to decrease a difference between said inertia phase time and a predetermined value.
Claim 2
Dependent Claim
218 words
A line pressure control system for an automatic transmission including a transmission input member and a transmission output member, the automatic transmission being shiftable between two gear ratios and including a friction device whcih is adpated to be engaged in response to a magnitude of a line pressure to effect a shifting between the two gear ratios, the line pressure control system, comprising: input sensor means for detecting a revolution speed of the transmission input member and generating a first sensor output signal indicative of said revolution speed of the transmission input member detected; output sensor means for detecting a revolution speed of the transmission output member and generating a second sensor output signal indicative of said revolution speed of the transmission output member detected; means responsive to said first and second sensor output signals for determining a gear ratio of said revolution speed of the transmission input member to said revolution speed of the transmission output member; means for measuring an inertia phase time when said gear ratio varies within a predetermined range during the shifting; means for adjusting the magnitude of the line pressure which the friction device is engaged on during the next occurrence of the shifting in such a manner as to decrease a difference between said inertia phase time and a predetermined value.
Claim 3
Dependent Claim
77 words
A line pressure control system as claimed in claim 1, wherein said adjusting means include a line pressure solenoid, means for containing first data, means for containing second correction data, means for controlling drive signal supplied to said line pressure solenoid in response to a sum of said first data and said second correction data, and means for modifying said second correction data in response to said difference between said inertia phase time and said predetermined value.
Claim 4
Independent Claim
206 words
A method of controlling a line pressure for an automatic transmission including a transmission input member and a transmission output member, the automatic transmission being shiftable between two gear ratios and including a friction device whcih is adpated to be engaged in response to a magnitude of a line pressure to effect a shifting between the two gear ratios, the method comprising the steps of: detecting a revolution speed of the transmission input member and generating a first sensor output signal indicative of said revolution speed of the transmission input member detected; detecting a revolution speed of the transmission output member and generating a second sensor output signal indicative of said revolution speed of the transmission output member detected; determining responsive to said first and second sensor output signals a gear ratio of said revolution speed of the transmission input member to said revolution speed of the transmission output member; measuring an inertia phase time when said gear ratio varies within a predetermined range during the shifting; adjusting the magnitude of the line pressure which the friction device is engaged on during the next occurrence of the shifting in such a manner as to decrease a difference between said inertia phase time and a predetermined value.
Claim 5
Independent Claim
206 words
A method of controlling a line pressure for an automatic transmission including a transmission input member and a transmission output member, the automatic transmission being shiftable between two gear ratios and including a friction device whcih is adpated to be engaged in response to a magnitude of a line pressure to effect a shifting between the two gear ratios, the method comprising the steps of: detecting a revolution speed of the transmission input member and generating a first sensor output signal indicative of said revolution speed of the transmission input member detected; detecting a revolution speed of the transmission output member and generating a second sensor output signal indicative of said revolution speed of the transmission output member detected; determining responsive to said first and second sensor output signals a gear ratio of said revolution speed of the transmission input member to said revolution speed of the transmission output member; measuring an inertia phase time when said gear ratio varies within a predetermined range during the shifting; adjusting the magnitude of the line pressure which the friction device is engaged on during the next occurrence of the shifting in such a manner as to decrease a difference between said inertia phase time and a predetermined value.
References Cited (Backward Citations)
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