Bicycle Torque Sensor Using Idler and Connecting Rod
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric assisted bicycles with dual side torque sensors are expensive, while mid- to low-end models using other sensors suffer from low precision, delayed power response, and short lifecycles, leading to an uncomfortable riding experience due to inaccurate and timely provision of electric assisted power.
Innovation Solution
A sensing device comprising a strain gauge device, an idler, and a connecting rod assembly that senses mechanical force from a transmission belt, providing precise measurement and generating a sensing signal to determine the need and amount of electric assisted power, while being cost-effective.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If dual side torque sensor is used, then measurement precision and power response speed are improved, but device cost increases significantly
Solution Approach 1:
The sensing device is segmented into three main components: idler, connecting rod assembly, and strain gauge device. This segmentation allows each component to perform a specific function, simplifying the overall system while maintaining measurement precision. The idler handles force reception, the connecting rod transmits force, and the strain gauge measures deformation, creating a modular and cost-effective solution.
Solution Approach 2:
The connecting rod assembly acts as an intermediary between the idler and the strain gauge device. It transmits the mechanical force from the idler to the strain gauge device, enabling indirect measurement that reduces complexity and cost while preserving measurement accuracy. This intermediary component allows the strain gauge to measure force without being directly exposed to the transmission belt.
2Device complexity
If conventional sensors (dropout sensor, torsion spring sensor, cadence sensor) are used, then device cost is reduced, but measurement precision and lifecycle are worsened
Solution Approach 1:
The patent replaces conventional mechanical sensors (dropout sensor, torsion spring sensor, cadence sensor) with a strain gauge device that measures mechanical force through deformation. This substitution transitions from indirect mechanical sensing to direct force measurement, significantly improving precision while maintaining cost-effectiveness and enhancing lifecycle through the durability of strain gauge technology.
3Device complexity
If conventional sensors are used, then device cost is reduced, but power response time is delayed
Solution Approach 1:
The strain gauge device provides direct electrical signals in response to mechanical force, eliminating the mechanical delays inherent in conventional sensors. The strain gauge converts deformation to electrical output almost instantaneously, significantly reducing power response time while keeping the device cost-effective.
4Device complexity
If conventional sensors are used, then device cost is reduced, but system reliability is worsened
Solution Approach 1:
The strain gauge device offers superior reliability compared to conventional mechanical sensors. It has no moving parts that wear out, resistant to fatigue, and provides consistent performance over time. This substitution enhances the sensing system lifecycle and overall reliability while maintaining cost-effectiveness, making it suitable for long-term use in electric assisted bicycles.
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 sensing device offers high measurement precision and cost-effectiveness, comparable to dual side torque sensors, with improved lifecycle and timely power response, enhancing the riding experience and market competitiveness.
Implementation Method 1
the strain gauge device receives the mechanical force to generate a deformation and further generates a sensing signal according to the deformation
Data Source
AI summary
A sensing device has a strain gauge device, an idler, and a connecting rod assembly. The sensing device receives a mechanical force to generate a deformation accordingly, and generates a sensing signal according to the deformation. The idler is a ring body which has a ring contracting portion contacting a transmission belt, so as to receive the mechanical force which the transmission belt applies on the idler. A first end of the connecting rod assembly is connected to the strain gauge device via a rod slot which is located on a side of the strain gauge device, and a second end of the connecting rod assembly is pivotally connected to the idler via a pivot connecting portion of the idler, such that the mechanical force which the idler suffers can be transmitted to the strain gauge device.