Three-Stage Speed-Change Mechanism With One-Way Bearing Shift Smoothing

Solution Overview

Problem

Existing speed change mechanisms for electric motorcycles are either complex and costly with difficult servicing or have poor efficiency, and often result in setbacks during speed changes.

Innovation Solution

A three-stage speed change mechanism with a simplified structure, featuring a gear ratio adjusting assembly and one-way bearings for smooth power transfer, allowing for direct power transfer and easy assembly and maintenance, eliminating setbacks during speed changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a gear-based speed changer is used, then speed switching efficiency is improved, but structure becomes complicated and servicing difficulty increases

Engineering Contradiction:

Improvespeed switching efficiencyVSAvoidstructure complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The transmission system is divided into three independent speed change assemblies (first, second, and third assemblies), each capable of operating independently. This segmentation allows the system to achieve multi-speed functionality without requiring a complex integrated gear mechanism, thereby maintaining structural simplicity while improving speed switching efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

One-way bearings are introduced as intermediary elements between the speed change assemblies and the output shaft. These bearings enable smooth power transfer and eliminate setting back during speed changes by allowing free rotation in one direction while preventing reverse motion, thus resolving the contradiction between efficiency and complexity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If a gear-based speed changer is used, then speed switching efficiency is improved, but servicing difficulty increases

Engineering Contradiction:

Improvespeed switching efficiencyVSAvoidservicing ease

Core Design Contradiction:

ProductivityVSEase of repair

Solution Approach 1:

The transmission system is divided into three independent speed change assemblies (first, second, and third assemblies), each capable of operating independently. This segmentation allows the system to achieve multi-speed functionality without requiring a complex integrated gear mechanism, thereby maintaining structural simplicity while improving speed switching efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

One-way bearings are introduced as intermediary elements between the speed change assemblies and the output shaft. These bearings enable smooth power transfer and eliminate setting back during speed changes by allowing free rotation in one direction while preventing reverse motion, thus resolving the contradiction between efficiency and complexity.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If speed change mechanism is added, then motor performance is maintained, but structure complexity increases

Engineering Contradiction:

Improvemotor performance stabilityVSAvoidtransmission structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The transmission system is divided into three independent speed change assemblies (first, second, and third assemblies), each capable of operating independently. This segmentation allows the system to achieve multi-speed functionality without requiring a complex integrated gear mechanism, thereby maintaining structural simplicity while improving speed switching efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

One-way bearings are introduced as intermediary elements between the speed change assemblies and the output shaft. These bearings enable smooth power transfer and eliminate setting back during speed changes by allowing free rotation in one direction while preventing reverse motion, thus resolving the contradiction between efficiency and complexity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11988269B2Three-stage speed-change mechanism

Publication Date: 2024.05.21 YAO LI HO

AI summary

A three-stage speed-change mechanism includes a casing in an interior of which a drive assembly, an input assembly, and an output assembly are arranged. The input assembly includes a transmission shaft driven by the drive wheel. An initial transmission wheel is mounted no a middle section of the transmission shaft. A first speed-change assembly and a second speed-change assembly are respectively arranged on two sides of the initial transmission wheel. The output assembly includes an output shaft, which is provided with an initial driven wheel and first and second speed-change wheels respectively mating the initial transmission wheel and the first and second speed-change assemblies. The initial driven wheel and the first speed-change wheel are respectively mounted by a first one-way bearing and a second one-way bearing on the output shaft. As such, a three-stage speed-change function is realized.