Chest Expander Friction Resistance Adjustment Without Batteries

Solution Overview

Problem

Existing chest expanders face issues with complex structures and high costs due to adjustable resistance mechanisms that require batteries.

Innovation Solution

A chest expander with a mechanical resistance adjustment mechanism using a resistance wheel, arc-shaped base strap, and friction plate, allowing for adjustable resistance through a screw and nut mechanism, and a magnetic counter for exercise data tracking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If electromagnetic resistance adjustment mechanism is used, then resistance can be adjusted, but structure becomes complex and cost increases

Engineering Contradiction:

Improveresistance adjustment capabilityVSAvoidstructure complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces the electromagnetic resistance adjustment mechanism with a purely mechanical friction-based system. A friction plate is pressed against the resistance wheel through a mechanical linkage connected to a调节 screw, eliminating the need for electromagnetic components, batteries, and complex control circuits while achieving adjustable resistance through simple mechanical means

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent uses simple, inexpensive mechanical components such as a friction plate, resistance wheel, and screw mechanism instead of expensive electromagnetic components. These mechanical parts are durable and can be easily replaced if needed, significantly reducing the overall cost of the device

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Adaptability or versatility

If electromagnetic resistance adjustment mechanism is used, then resistance can be adjusted, but cost increases

Engineering Contradiction:

Improveresistance adjustment capabilityVSAvoidmanufacturing cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent uses simple, inexpensive mechanical components such as a friction plate, resistance wheel, and screw mechanism instead of expensive electromagnetic components. These mechanical parts are durable and can be easily replaced if needed, significantly reducing the overall cost of the device

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent replaces the electromagnetic resistance adjustment mechanism with a purely mechanical friction-based system. A friction plate is pressed against the resistance wheel through a mechanical linkage connected to a调节 screw, eliminating the need for electromagnetic components, batteries, and complex control circuits while achieving adjustable resistance through simple mechanical means

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Adaptability or versatility

If electromagnetic resistance adjustment mechanism is used, then resistance can be adjusted, but battery is required

Engineering Contradiction:

Improveresistance adjustment capabilityVSAvoidenergy consumption

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent replaces the electromagnetic resistance adjustment mechanism with a purely mechanical friction-based system. A friction plate is pressed against the resistance wheel through a mechanical linkage connected to a调节 screw, eliminating the need for electromagnetic components, batteries, and complex control circuits while achieving adjustable resistance through simple mechanical means

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The mechanical friction-based resistance adjustment system is self-powered through manual operation. The user directly adjusts the resistance by rotating the调节 screw, which mechanically presses the friction plate against the resistance wheel without requiring any external energy source or battery

Inventive Principle:

Principle #25Self-service

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 mechanical adjustment provides a simpler structure and lower costs without the need for batteries, while accurately tracking exercise data.

Implementation Method 1

the elastic member drives the winding storage wheel to rotate to wind and store the pull strap

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

the friction plate is arranged on an inner surface of the arc-shaped base strap and is in frictional contact with the peripheral surface of the resistance wheel

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentUS12357867B2Chest expander

Publication Date: 2025.07.15 XU JIAN

AI summary

A chest expander comprises a shell, a rotating shaft, a winding storage wheel, an elastic member, and a pull strap, further comprises a resistance adjustment mechanism, and the resistance adjustment mechanism comprises a resistance wheel, an arc-shaped base strap, and a friction plate, wherein the resistance wheel is arranged on the rotating shaft, the arc-shaped base strap is arranged opposite to a peripheral surface of the resistance wheel, and the friction plate is arranged on an inner surface of the arc-shaped base strap and is in frictional contact with the peripheral surface of the resistance wheel; and one end of the arc-shaped base strap is fixedly connected to the shell, and the other end is movable and adjustable to adjust friction between the friction plate and the resistance wheel. the utility model employs purely mechanical adjustment, which achieves a simpler structure and can greatly reduce costs.