Control apparatus and method for automatic transmission

A control method for an automatic transmission adapted to achieve a plurality of transmission ratios by changing an engagement state of a friction element in order to transmit torque from a drive source to a drive wheel, the control method comprising:

• performing a shift-pressure learning correction in which a physical quantity representing a progress of shift is measured during a current downshift, and in which an engagement command pressure for the friction element is corrected during a next downshift on a basis of a divergence between the measured physical quantity and a target physical quantity;
• performing a torque increase control in which a command for temporarily increasing torque of the drive source starts to be outputted when a start estimation timing of torque phase that is preset by a time management has just come during a shift transition period given between a shift start and a shift end of the downshift;
• judging on a processor whether or not the shift-pressure learning correction has converged;
• prohibiting the torque increase control until it is decided that the shift-pressure learning correction has converged;
• and
• permitting the torque increase control when it is decided that the shift pressure learning correction has converged.

A control apparatus for an automatic transmission adapted to achieve a plurality of transmission ratios by changing an engagement state of a friction element in order to transmit torque from a drive source to a drive wheel, the control apparatus comprising:

• a processor performing a shift-pressure learning correction in which a physical quantity representing a progress of shift is measured during a current downshift, and in which an engagement command pressure for the friction element is corrected during a next downshift on a basis of a divergence between the measured physical quantity and a target physical quantity;
• means for performing a torque increase control in which a command for temporarily increasing torque of the drive source starts to be outputted when a start estimation timing of torque phase that is preset by a time management has just come during a shift transition period given between a shift start and a shift end of the downshift;
• means for judging whether or not the shift-pressure learning correction has converged;
• means for prohibiting the torque increase control until it is decided that the shift-pressure learning correction has converged;
• and
• means for permitting the torque increase control when it is decided that the shift-pressure learning correction has converged.