To provide a speed-change controller of automatic transmission which can improve drivability when speed is changed by accurately studying an engaging-side hydraulic pressure.
The speed-change controller of automatic transmission as follows: a transmission ECU increases an engine torque and obtains a turbine rotation number NT (A) when a downshift instruction is obtained (step S12); a turbine rotation number NT (B) is obtained (step S14), and a variation gradient of the turbine rotation number is calculated as a real ΔNT (step S15) after a measuring time T passes; a target ▵NT is calculated based on a vehicle speed and an engine torque Te (step S16); and the transmission ECU sets a value obtained by subtracting a compensating hydraulic pressure ▵P' from this engaging-side hydraulic pressure P as a next engaging-side hydraulic pressure (step S18) when the real ▵NT is the target ▵NT or more, and sets a value obtained by adding a compensating hydraulic pressure ▵P to this engaging-side hydraulic pressure P as a next engaging-side hydraulic pressure (step S19) when the real ▵NT is less than the target ▵NT.
COPYRIGHT: (C)2010,JPO&INPIT
KITAJIMA KEI
MATSUNAGA HITOSHI
| JP2008045676A | 2008-02-28 | |||
| JPH1018876A | 1998-01-20 | |||
| JPH0611031A | 1994-01-21 | |||
| JP2004316838A | 2004-11-11 |
Eigarou Ariga
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