Automatic Transmission Controller Torque Phase Inertia Phase Transition

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Solution Overview

Problem

During power-on upshift in automatic transmissions, the torque capacity of the engaging engagement device increases excessively, leading to a 'jump-out feeling or shift shock when the inertia phase begins, as the torque phase control continues.

Innovation Solution

A controller is implemented that adjusts the engaging target clutch torque capacity by subtracting a correction amount based on the difference between the actual and target torque capacities at the start of the inertia phase, ensuring a smoother transition from torque phase to inertia phase control, thereby preventing excessive torque capacity and shift shock.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If torque phase control is executed during power-on upshift, then the torque capacity of the engaging engagement device increases to target torque capacity, but the actual torque capacity becomes excessive causing jump-out feeling or shift shock

Engineering Contradiction:
Improvetorque capacityVSAvoidjump-out feeling or shift shock
Core Design Contradiction:
PowerVSObject-affected harmful factors

Solution Approach 1:

The controller determines whether the inertia phase has started before completing the torque phase control. When the inertia phase is detected to have started, the controller interrupts the torque phase control to prevent the engaging engagement device's torque capacity from becoming excessive, thereby avoiding jump-out feeling or shift shock before they occur.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The controller continuously monitors the transmission operation state to detect when the inertia phase has started during power-on upshift. Based on this feedback information, the controller dynamically adjusts the torque phase control execution, interrupting it when necessary to maintain appropriate torque capacity levels and prevent harmful effects.

Inventive Principle:
Principle #23Feedback

2Manufacturing precision

If the torque capacity increases to target torque capacity through torque phase control, then the shifting completeness is improved, but the shift smoothness deteriorates due to excessive torque capacity

Engineering Contradiction:
Improveshifting completenessVSAvoidshift smoothness
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The controller dynamically adjusts the torque phase control execution based on real-time detection of the inertia phase start. By conditionally interrupting the torque phase control when the inertia phase begins, the system adapts the torque capacity increase profile to maintain both shifting completeness and shift smoothness under varying operational conditions.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3276227B1Controller for automatic transmissions to avoid a shift shock
Publication Date: 2019.08.21 TOYOTA JIDOSHA KK
  • EP3276227B1 patent drawingFigure 1
  • EP3276227B1 patent drawingFigure 2
  • EP3276227B1 patent drawingFigure 3

AI summary

When an inertia phase has started while torque phase control is being executed, the torque phase control is ended, a target torque capacity of an engaging element in inertia phase control is corrected on the basis of a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element at the time when the torque phase control has completed (or a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element, which is set at the time when the inertia phase control has started), and the inertia phase control is started.