Power Transmission Control Device Synchronization

Solution Overview

Problem

In non-synchronous transmissions, the existing gear engagement mechanisms can cause discomfort to drivers due to prolonged engagement times and potential excessive load on components, as they rely on repeated torque adjustments and lack synchronization of rotation speeds.

Innovation Solution

A power transmission control device that includes a first and second rotation shaft, rotation speed detection units, an engagement member, and a control unit capable of calculating differential rotation and synchronizing engagement speeds to smoothly transition between gear states, reducing load and improving engagement efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the engagement operation is repeated by strengthening or weakening torque to allow the sleeve to engage with the gear, then the gear engagement is achieved, but the engagement time becomes prolonged causing driver discomfort

Engineering Contradiction:

Improvegear engagement reliabilityVSAvoidengagement time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The control unit performs preliminary synchronization of rotation speeds before the engagement operation. By calculating the rotation speed of the idle gear based on the output shaft rotation speed and gear ratios, and controlling the engine or motor generator to match these speeds in advance, the system ensures that N1 equals N2 before engagement, eliminating the need for repeated torque adjustments and reducing engagement time

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from rotation speed detection units to continuously monitor the rotation speeds of both the sleeve and idle gear. The control unit adjusts the engine or motor generator output based on this feedback to maintain N1 equal to N2, ensuring accurate synchronization before engagement and preventing prolonged engagement operations

Inventive Principle:

Principle #23Feedback

2Reliability

If the engagement operation is repeated by strengthening or weakening torque, then the gear engagement is achieved, but excessive load is applied to the sleeve and gear

Engineering Contradiction:

Improvegear engagement reliabilityVSAvoidcomponent load

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The control unit performs preliminary synchronization of rotation speeds before the engagement operation. By calculating the rotation speed of the idle gear based on the output shaft rotation speed and gear ratios, and controlling the engine or motor generator to match these speeds in advance, the system ensures that N1 equals N2 before engagement, eliminating the need for repeated torque adjustments and reducing engagement time

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from rotation speed detection units to continuously monitor the rotation speeds of both the sleeve and idle gear. The control unit adjusts the engine or motor generator output based on this feedback to maintain N1 equal to N2, ensuring accurate synchronization before engagement and preventing prolonged engagement operations

Inventive Principle:

Principle #23Feedback

3Productivity

If the sleeve is forcedly engaged with the gear when rotation speeds are matched, then engagement is achieved, but collision sound is generated causing driver discomfort

Engineering Contradiction:

Improveengagement speedVSAvoidcollision sound

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The control unit performs preliminary synchronization of rotation speeds before the engagement operation. By calculating the rotation speed of the idle gear based on the output shaft rotation speed and gear ratios, and controlling the engine or motor generator to match these speeds in advance, the system ensures that N1 equals N2 before engagement, eliminating the need for repeated torque adjustments and reducing engagement time

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from rotation speed detection units to continuously monitor the rotation speeds of both the sleeve and idle gear. The control unit adjusts the engine or motor generator output based on this feedback to maintain N1 equal to N2, ensuring accurate synchronization before engagement and preventing prolonged engagement operations

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS11603924B2Power transmission control device

Publication Date: 2023.03.14 AISIN AW CO LTD

AI summary

A power transmission control device acquires rotation speed information of an idle gear corresponding to a target engagement member and rotation speed information of a sleeve corresponding to an engagement member, sets one rotation speed changeable by a power source as a synchronization side rotation speed, sets the other rotation speed as a target synchronization side rotation speed, allows a differential rotation between the synchronization side rotation speed and the target synchronization side rotation speed to match a predetermined differential rotation by changing the synchronization side rotation speed using the power source after a power transmission releasing state is selected due to a gear changing request, performs an engagement operation, inverts a sign of the predetermined differential rotation, and switches to the power transmission state while allowing the differential rotation to match the predetermined differential rotation of which the sign is inverted.