Starter-Generator Torque Transmission Mechanism

Solution Overview

Problem

Integrated starter-generators face challenges in efficiently providing engine-cranking torque and stable power generation when they have low output power and torque requirements, leading to increased component costs and reduced efficiency.

Innovation Solution

A starter-generator system with a torque transmission mechanism and belt drive mechanism that includes pulleys and one-way clutches, allowing for selective transmission of engine-cranking and generator-cranking torque at specific gear ratios, reducing component costs and enhancing starting efficiency and power generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a low-capacity starter-generator is used, then component cost and weight are reduced, but engine-cranking torque and power generation stability deteriorate

Engineering Contradiction:

Improvecomponent costVSAvoidengine-cranking torque

Core Design Contradiction:

Ease of manufactureVSForce

Solution Approach 1:

The system dynamically switches between two operational modes: starting mode where the torque transmission mechanism engages to multiply torque, and generating mode where the mechanism disengages for direct 1:1 torque transmission. This dynamic configuration allows a low-capacity starter-generator to deliver high cranking torque when needed while maintaining cost-effectiveness

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The torque transmission mechanism is segmented into two distinct pathways: one for engine starting with gear ratio multiplication, and another for power generation with direct transmission. This segmentation allows the system to optimize performance for each specific function independently

Inventive Principle:

Principle #1Segmentation

2Ease of manufacture

If a low-capacity starter-generator is used, then component cost is reduced, but power generation stability deteriorates

Engineering Contradiction:

Improvecomponent costVSAvoidpower generation stability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The system dynamically switches between two operational modes: starting mode where the torque transmission mechanism engages to multiply torque, and generating mode where the mechanism disengages for direct 1:1 torque transmission. This dynamic configuration allows a low-capacity starter-generator to deliver high cranking torque when needed while maintaining cost-effectiveness

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The torque transmission mechanism is extracted and separated from the direct drive path during power generation mode, allowing the starter-generator to operate independently without the complexity and cost of continuously engaged transmission components

Inventive Principle:

Principle #2Taking out (Extraction)

3Reliability

If high output power and torque requirements are imposed on the starter-generator, then engine starting reliability is improved, but component cost and device complexity increase

Engineering Contradiction:

Improveengine starting reliabilityVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The system dynamically switches between two operational modes: starting mode where the torque transmission mechanism engages to multiply torque, and generating mode where the mechanism disengages for direct 1:1 torque transmission. This dynamic configuration allows a low-capacity starter-generator to deliver high cranking torque when needed while maintaining cost-effectiveness

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The torque transmission mechanism is pre-configured with gear ratios optimized for engine starting, and the one-way clutches are pre-positioned to automatically engage/disengage based on operational mode, eliminating the need for complex control systems

Inventive Principle:

Principle #10Preliminary action

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 system effectively increases engine-cranking torque and maintains stable power generation with low-capacity starter-generators, reducing overall component and manufacturing costs while improving starting efficiency and power generation efficiency.

Implementation Method 1

a belt frictionally engaging the two pulleys and the crank pulley

Methodology Applied

Scientific EffectFriction: Friction

Implementation Method 2

a one-way clutch configured to transmit the torque from the first shaft to the first pulley or allow the first pulley to rotate freely

Methodology Applied

Scientific EffectMechanical Advantage: Mechanical Advantage

Data Source

PatentUS10352286B2Starter-generator system

Publication Date: 2019.07.16 HYUNDAI MOTOR CO LTD

AI summary

A starter-generator system may include a starter-generator configured to provide an engine-cranking torque or receive a generator-cranking torque, a belt drive mechanism located between the starter-generator and an engine, and a torque transmission mechanism that selectively transmits the engine-cranking torque or the generator-cranking torque between the starter-generator and the belt drive mechanism.