Engine torque compensation shift scheduling of an automatic transmission for motor vehicles

A system for controlling gear ratio changes in an automatic transmission for use in a motor vehicle, comprising:

• an engine having a variable position throttle for controlling the engine;
• means containing a gearshift schedule developed at reference engine output torque BTR BASE, the schedule defining conditions under which upshifts in gear ratio from a current gear ratio can occur;
• means for calculating current engine output torque TQ NET;
• means for determining current engine speed;
• means for determining an engine speed adjustment to account for a difference between the current engine output torque and reference BTR BASE;
• means for determining the gearshift schedule a predetermined engine speed NEXXS above which an upshift from the current gear ratio can occur;
• means for calculating engine torque compensation engine speed from said engine speed adjustment and said predetermined engine speed;
• means for comparing current engine speed to the engine torque compensated engine speed;
• and
• means for producing an upshift when said comparison indicates current engine speed exceeds said engine torque compensated engine speed.

A method for controlling gear ratio changes in a multiple gear ratio automatic transmission for a motor vehicle having an engine controlled by its throttle position, comprising the steps of:

• developing a gearshift schedule at reference engine output torque BTR BASE, the schedule defining conditions under which upshifts in gear ratio from a current gear ratio can occur;
• determining the current magnitude of reference engine output torque BTR BASE;
• calculating current engine output torque TQ NET;
• determining a vehicle speed adjustment to account for a difference between the current engine output torque TQ NET and reference BTR BASE;
• determining from the gearshift schedule a predetermined vehicle speed FNXXS above which an upshift from the current gear ratio can occur;
• calculating engine torque compensation vehicle speed from said vehicle speed-adjustment and said predetermined vehicle speed;
• comparing current vehicle speed to the engine torque compensated vehicle speed;
• and
• producing an upshift when said comparison indicates current vehicle speed exceeds said engine torque compensated vehicle speed.

A method for controlling gear ratio changes in a multiple gear ratio of an automatic transmission for a motor vehicle having an engine controlled by its throttle position, comprising the steps of:

• developing a gearshift schedule at reference engine output torque BTR BASE, the schedule defining conditions under which downshifts in gear ratio from a current gear ratio can occur;
• determining the current magnitude of reference engine output torque BTR BASE;
• calculating current engine output torque TQ NET;
• determining an engine speed adjustment to account for a difference between the current engine output torque and reference BTR BASE;
• determining from the gearshift schedule a predetermined engine speed NEXXS above which an upshift from the current gear ratio can occur;
• calculating engine torque compensated engine speed from said engine speed adjustment and said predetermined engine speed;
• comparing current engine speed to the engine torque compensated engine speed;
• and
• producing an upshift when said comparison indicates current engine speed exceeds said engine torque compensated vehicle speed.

A method for controlling gear ratio changes in a multiple gear ratio automatic transmission for a motor vehicle having an engine controlled by its throttle position, comprising the steps of:

• developing a gearshift schedule at reference engine output torque BTR BASE, the schedule defining conditions under which downshifts in gear ratio from a current gear ratio can occur;
• determining the current magnitude of reference engine output torque BTR BASE;
• calculating current engine output torque TQ NET;
• determining a vehicle speed adjustment to account for a difference between the current engine output torque and reference BTR BASE;
• determining from the gearshift schedule a predetermined vehicle speed FNXXS below which an downshift from the current gear ratio can occur;
• calculating engine torque compensation vehicle speed from said vehicle speed adjustment and said predetermined vehicle speed;
• comparing current vehicle speed to the engine torque compensated vehicle speed;
• and
• producing an downshift when said comparison indicates current vehicle speed is less than said engine torque compensated vehicle speed.

A method for controlling, with the aid of a digital computer, gear ratio changes in a motor vehicle, multiple gear ratio automatic transmission having an engine controlled by its throttle position, comprising the steps of:

• providing said computer with a data base including at least:
• a gearshift schedule at reference engine output torque BTR BASE, the schedule defining conditions under which upshifts in gear ratio from a current gear ratio can occur;
• current magnitude of reference engine output torque BTR BASE;
• a vehicle speed adjustment to account for a difference between the current engine output torque and reference BTR BASE;
• repetitively calculating in the computer current engine output torque TQ NET;
• repetitively determining in the computer the current magnitude of engine output torque;
• repetitively determining from the gearshift schedule a predetermined vehicle speed FNXXS above which an upshift from the current gear ratio can occur;
• repetitively calculating in the computer engine torque compensation vehicle speed from said vehicle speed adjustment and said predetermined vehicle speed;
• repetitively comparing in the computer current vehicle speed to the engine torque compensated vehicle speed;
• and
• producing an upshift when said comparison indicates current vehicle speed exceeds said engine torque compensated vehicle speed.

A method for controlling, with the aid of a digital computer, gear ratio changes in a motor vehicle, multiple gear ratio automatic transmission having an engine controlled by its throttle position, comprising the steps of:

• providing said computer with a data base including at least:
• a gearshift schedule at reference engine output torque BTR BASE, the schedule defining conditions under which upshifts in gear ratio from a current gear ratio can occur;
• an engine speed adjustment to account for a difference between the current engine output torque and reference BTR BASE;
• repetitively calculating in the computer current engine output torque TQ NET;
• repetitively determining from the gearshift schedule a predetermined engine speed NEXXS above which an upshift from the current gear ratio can occur;
• repetitively calculating in the computer reference engine torque BTR BASE compensated engine speed from said predetermined engine speed and predetermined engine speed adjustment NEXXTQ;
• repetitively comparing in the computer current engine speed to the engine torque compensated engine speed;
• and
• producing an upshift when said comparison indicates current engine speed exceeds said engine torque compensated engine speed.