Electric Vehicle Powertrain Torque Converter Gear Sets

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Modern electric vehicles face a tradeoff between extending range and maintaining performance attributes like drivability, launch performance, and maneuverability, as resizing the motor generator unit (MGU) to conserve battery energy can compromise these aspects.

Innovation Solution

A powertrain design incorporating a motor generator unit, torque converter, shafts, gear sets, and a torque transmitting mechanism that allows for selective gear ratios and modes of operation, including initial and secondary forward launch modes and reverse launch mode, to optimize torque transfer and improve vehicle performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the motor generator unit is resized to use less battery energy, then energy consumption is reduced and range is extended, but drivability, launch performance, and maneuverability deteriorate

Engineering Contradiction:

Improvebattery energy consumptionVSAvoiddrivability and launch performance

Core Design Contradiction:

Use of energy by moving objectVSEase of operation

Solution Approach 1:

The powertrain is segmented into multiple gear sets (first gear set with first and second gears, second gear set with third and fourth gears) and a planetary gear set, allowing the system to provide different gear ratios without requiring a larger motor generator unit. This segmentation enables optimized energy consumption while maintaining performance across different operating conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The torque transmitting mechanism dynamically engages and disengages different gear sets based on operating conditions. The system can selectively transfer torque through different pathways (direct drive, first gear set, second gear set, or planetary gear set), allowing the motor generator unit to operate at optimal efficiency points while maintaining drivability and launch performance through appropriate gear selection.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If a larger motor generator unit is used to improve drivability and launch performance, then vehicle performance improves, but energy consumption increases and range decreases

Engineering Contradiction:

Improvedrivability and launch performanceVSAvoidbattery energy consumption

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The system changes operational parameters by providing multiple gear ratios through different gear sets and a planetary gear set. This allows a smaller, more energy-efficient motor generator unit to deliver high torque at launch and maintain drivability across the full speed range by optimizing the gear ratio selected for each operating condition, rather than requiring a larger motor that consumes more energy at all times.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If multiple gear sets and torque transmitting mechanisms are added to optimize torque transfer, then vehicle performance and range are improved, but device complexity increases

Engineering Contradiction:

Improvevehicle performance and rangeVSAvoidpowertrain structure

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent merges multiple gear sets (first gear set, second gear set) with a planetary gear set into a single integrated powertrain architecture. The torque transmitting mechanism selectively engages these combined elements to provide multiple gear ratios, achieving improved vehicle performance and range while containing complexity through unified design rather than separate systems.

Inventive Principle:

Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The powertrain enhances vehicle performance while extending range capabilities, providing improved drivability and launch performance without compromising affordability through cost reduction.

Implementation Method 1

The torque converter includes a pump and a turbine. The pump is connected for common rotation with the output member of the motor generator unit. The first shaft rotatably is supported by the powertrain housing and is connected for common rotation with the turbine of the torque converter.

Methodology Applied

Scientific EffectTorque converter fluid coupling: Hydraulic Press

Implementation Method 2

The first gear set includes a first gear and a second gear with the first gear rotatably supported by the first shaft and the second gear is connected for common rotation with the second shaft. The second gear set has a third gear and a fourth gear with the third gear rotatably supported by the first shaft and the fourth gear connected for common rotation with the second shaft.

Methodology Applied

Scientific EffectGear mechanical advantage: Gear

Data Source

PatentUS10974593B2Powertrain for an electric vehicle

Publication Date: 2021.04.13 GM GLOBAL TECHNOLOGY OPERATIONS LLC

AI summary

A powertrain for a vehicle includes a housing, a motor generator unit, a torque converter, a first and second shafts, a first and second gear sets, and a torque transmitting mechanism. The motor generator unit includes an output member. The torque converter includes a pump and a turbine. The pump is connected for common rotation with the output member of the motor generator unit. The first shaft rotatably is supported by the powertrain housing and is connected for common rotation with the turbine of the torque converter. The second shaft is rotatably supported by the powertrain housing and disposed parallel to the first shaft. An output gear is connected for common rotation to the second shaft.