Double Clutch Transmission Torque Interruption Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional double clutch transmissions lack responsiveness and quick reaction to shift requests, resulting in a perceived delay and lack of driver feedback, as they require the incoming clutch to prepare for torque transfer before the active clutch can reduce torque, leading to comfortable but slow shifting.

Innovation Solution

Implementing a method that allows for torque interruption during shifts, enabling a gradual transition from comfortable to responsive shifting by adjusting the amount of torque interruption based on driving conditions and mode selected by the driver, using a Double Clutch Transmission (DCT) with a CAN bus communication between the engine control unit (ECU) and transmission control unit (TCU) to manage engine and clutch torque.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If conventional powershift method is used where incoming clutch prepares for torque transfer before active clutch reduces torque, then shifting comfort is improved, but shifting responsiveness and reaction speed deteriorate

Engineering Contradiction:
Improveshifting comfortVSAvoidshifting responsiveness
Core Design Contradiction:
Ease of operationVSSpeed

Solution Approach 1:

The patent implements dynamic shift control that adapts the shifting strategy based on driver-selected modes. In sport mode, the system dynamically allows torque interruption and reduces active clutch torque earlier, prioritizing responsiveness. In comfort mode, it maintains the conventional powershift approach. This dynamic adaptation resolves the contradiction by making the system flexible rather than fixed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes key torque parameters dynamically during the shift process. By adjusting when and how much the active clutch torque is reduced, and controlling the torque interruption level, the system can optimize for either comfort or responsiveness. The control unit modifies torque transfer characteristics based on the selected driving mode, resolving the trade-off between comfort and responsiveness.

Inventive Principle:
Principle #35Parameter changes

2Stability of the object's composition

If incoming clutch is required to reach touch point and prepare for torque transfer before active clutch reduces torque, then torque handover smoothness is improved, but shift preparation time and perceived delay increase

Engineering Contradiction:
Improvetorque handover smoothnessVSAvoidshift preparation time
Core Design Contradiction:
Stability of the object's compositionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by having the incoming clutch begin its engagement process earlier in the shift sequence, before the active clutch fully reduces torque. In sport mode, the system initiates incoming clutch preparation without waiting for optimal touch point conditions, reducing perceived delay while maintaining acceptable smoothness through active clutch torque management.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent uses partial action by allowing incomplete or interrupted torque transfer during the shift process in sport mode. The active clutch torque is reduced before the incoming clutch is fully ready, creating a controlled torque interruption that reduces preparation time while accepting some loss of smoothness to achieve faster response.

Inventive Principle:
Principle #16Partial or excessive action

3Power

If active clutch reduces torque only when incoming clutch is ready to transfer torque, then complete engine torque is maintained during shift, but driver feedback and sportiness deteriorate

Engineering Contradiction:
Improveengine torque continuityVSAvoiddriver feedback
Core Design Contradiction:
PowerVSEase of operation

Solution Approach 1:

The patent makes engine torque continuity dynamic rather than constant. In sport mode, the system dynamically allows torque interruption by reducing active clutch torque earlier, providing driver feedback and sportiness. In comfort mode, it maintains continuous torque. This dynamic behavior resolves the contradiction by adapting power delivery to driver expectations.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent introduces feedback by creating a visible and perceptible response to driver input through torque interruption. When the driver requests a shift in sport mode, the torque interruption provides immediate feedback that the system has registered and is executing the command, enhancing the sporty driving experience and driver engagement.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2149728B1Method of controlling a double clutch transmission
Publication Date: 2012.06.27 HOERBIGER DRIVETRAIN MECHATRONICS B A
  • EP2149728B1 patent drawingFigure 1~2
  • EP2149728B1 patent drawingFigure 3~4
  • EP2149728B1 patent drawingFigure 5~6

AI summary

The present invention concerns a method of controlling a double clutch transmission (1) comprising two clutches (2A, 2B) one of which that is transmitting torque being the active clutch whilst the other one constituting the incoming clutch characterized by creating a torque interruption by decreasing engine torque and active clutch torque while keeping the incoming clutch inactive or preparing it to transfer torque.