Drive Control Device Torque Limiting During Gear Shift

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Solution Overview

Problem

During gear shift control, the target torque set by the driver can exceed the engine's generable torque when the accelerator is fully opened, leading to shocks or oscillations due to the deviation between the two, which compromises drivability and transmission durability.

Innovation Solution

A drive control device that executes torque reduction control by limiting the target torque to the engine's generable torque during gear shift, using a control unit that receives signals from intake air temperature and engine rotational speed sensors to determine the actual torque capability and adjust the target torque accordingly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the target torque is set based on accelerator opening degree during gear shift control, then the driver's torque request is fulfilled, but the target torque may exceed the engine's generable torque causing shocks and oscillations

Engineering Contradiction:
Improvedriver torque request fulfillmentVSAvoiddrivability stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The control device determines the engine's generable torque in advance before setting the target torque during gear shift control. By establishing the torque limit based on generable torque beforehand, the system prevents the target torque from exceeding what the engine can actually deliver, thereby avoiding shocks and oscillations while still responding to driver requests

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The control device continuously monitors the relationship between the target torque (based on accelerator opening) and the engine's generable torque. When the target torque exceeds the generable torque, the system provides feedback to limit the target torque to the generable torque value, ensuring the engine operates within its actual capability and preventing drivability disturbances

Inventive Principle:
Principle #23Feedback

2Object-affected harmful factors

If torque reduction control is executed during gear shift, then gear shift shocks are alleviated, but the target torque may deviate from generable torque when accelerator is fully opened

Engineering Contradiction:
Improvegear shift shocksVSAvoidtorque consistency
Core Design Contradiction:
Object-affected harmful factorsVSStability of the object's composition

Solution Approach 1:

The control device dynamically adjusts the target torque based on real-time conditions. During gear shift control, when the accelerator is fully opened and the calculated target torque exceeds the engine's generable torque, the system dynamically limits the target torque to match the generable torque. This dynamic adjustment maintains torque consistency and prevents shocks while still providing torque reduction during gear shift

Inventive Principle:
Principle #15Dynamics

3Productivity

If the torque limit is released after gear shift control, then normal torque response is restored, but shocks occur due to deviation between target torque and generable torque

Engineering Contradiction:
Improvetorque response speedVSAvoiddrivability stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The control device continuously monitors the relationship between target torque and generable torque even after gear shift control ends. When the accelerator is fully opened and target torque exceeds generable torque, the system provides feedback to limit the target torque, preventing shocks and oscillations while maintaining normal torque response capability

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2980387B1Drive control device
Publication Date: 2018.03.14 SUZUKI MOTOR CORP
  • EP2980387B1 patent drawingFigure 1
  • EP2980387B1 patent drawingFigure 2
  • EP2980387B1 patent drawingFigure 3

AI summary

The objective of the present invention is to suppress shocks and vibrations from being imparted to a driver by means of the generated torque of an engine when executing torque reduction control during gear shifting. In this drive control device able to execute torque reduction control during gear shifting, when executing torque reduction control, torque limiting is performed on the basis of the generatable torque in the case that the requested torque called for on the basis of an accelerator aperture exceeds the generatable torque that is the torque that can be generated by the engine.