US 7,008,344 B2Granted

Control apparatus for controlling a shift operation in an automatic transmission

AssigneeAisin Seiki Kabushiki Kaisha

InventorsAkira Aikawa, Hiroaki Kato, Katsutoshi Sato, Yasuo Shirai, Atsumi Ohara

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Abstract

A control apparatus for controlling a shift operation in an automatic transmission includes a disengaging side controlling device for performing a feedback control so as to substantially match a slip amount calculated by a slip amount calculating device with a target slip amount calculated by a target slip amount calculating device when the calculated slip amount is judged to be in excess of the predetermined threshold value by a judging device. The target slip amount varies from a predetermined threshold value to a predetermined target value drawing an ideal trace for restraining a shift shock and is maintained at the predetermined target value. The control apparatus further includes an engaging side controlling device for increasing a torque to be transmitted to an on-coming friction engagement element in association with commencement of the feedback control.

Claims13

Dependent claims

A control apparatus for controlling a torque phase of an up-shifting operation in an automatic transmission having a torque converter, an input shaft of the automatic transmission connected to a turbine runner in the torque converter, an output shaft of the automatic transmission, and plural friction engagement elements selectively engaged or disengaged to connect or disconnect the input shaft with the output shaft indirectly for establishing plural shaft stages, wherein when up-shifting from one shift stage of the plural shift stages to another shift stage an off-going friction engagement element of the plural friction engagement elements is switched from an engaged condition to a disengaged condition for reducing torque transmitted by decreasing a hydraulic pressure supplied such that the off-going friction element starts to slip, and an on-coming friction engagement element of the plural friction engagement elements is switched from a disengaged condition to an engaged condition for multiplying transmitted torque by increasing supplied hydraulic pressure such that the on-going friction element stops slipping, the control apparatus comprising:

a slip amount calculating means for calculating a slip amount based upon a rotational speed of the input shaft and a rotational speed of the output shaft thereof;
a judging means for judging whether or not the calculated slip amount is greater than a predetermined threshold value by comparison;
a target slip amount calculating means for calculating a target slip amount, the target slip amount varied from the predetermined threshold value to a predetermined target value drawing an ideal trace for restraining a shift shock of the torque phase of the up-shifting operation;
a disengaging side controlling means for starting to perform an integral-proportional feedback control so as to substantially match the calculated slip amount with the calculated target slip amount for restraining over rotation of the turbine runner due to the up-shifting operation when the calculated slip amount is judged to be in excess of the predetermined threshold value by the judging means;
and
an engaging side controlling means for increasing the torque to be transmitted to the on-coming friction engagement element in association with commencement of the integral-proportional feedback control.

3 more elements

A control apparatus for controlling a torque phase of an up-shifting operation in an automatic transmission having plural friction engagement elements selectively engaged or disengaged to connect or disconnect an input shaft of the automatic transmission with an output shaft of the automatic transmission indirectly for establishing plural shift stages along with control of an oil pressure to be supplied thereto, wherein an off-going friction engagement element of the plural friction engagement elements is switched from an engaged condition to a disengaged condition by reducing torque transmitted to the off-going friction engagement element in response to reduction of the oil pressure supplied to the off-going friction engagement element when up-shifting from a shift stage of the plural shift stages to another shift stage thereof such that the off-going friction engagement element slips, and an on-coming friction engagement element of the plural friction engagement elements is switched from a disengaged condition to an engaged condition by increasing torque to be transmitted to the on-coming friction engagement element in response to increase of the oil pressure to be supplied to the on-coming friction engagement element at the time of shifting, the control apparatus comprising:

a slip amount calculating means for calculating a slip amount based upon a rotational speed of the input shaft and a rotational speed of an output shaft thereof;
a judging means for judging whether or not the calculated slip amount is greater than a predetermined threshold value by comparison;
a target slip amount calculating means for calculating a target slip amount, the target slip amount varied from the predetermined threshold value to a predetermined target value drawing an ideal trace for restraining a shift shock of the torque phase of the up-shifting operation;
a disengaging side controlling means for starting to perform an integral-proportional feedback control so as to substantially match the calculated slip amount with the calculated target slip amount for preventing an over rotation of the input shaft due to the up-shifting operation when the calculated slip amount is judged to be in excess of the predetermined threshold value by the judging means;
and
an engaging side controlling means for increasing the torque to be transmitted to the on-coming friction engagement element in association with commencement of the integral-proportional feedback control.

3 more elements

Dependencies are inferred from the claim text.