Rotary Switch With Integral Bimetal Overcurrent Protection

Solution Overview

Problem

In many electrical wiring arrangements, separate circuit breakers or overcurrent protection devices are required in addition to switches, which increases complexity, cost, and space usage, especially in low-voltage applications where ease of use and minimal voltage drop are desired.

Innovation Solution

A rotary switch with an integrated overcurrent protection device, featuring a bimetallic element that changes shape in response to excessive current, automatically disconnecting the circuit and including a reset mechanism to restore functionality, thereby combining switching and overcurrent protection in a single device.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate circuit breakers or overcurrent protection devices are provided in addition to switches, then overcurrent protection is achieved, but device complexity and installation complexity increase

Engineering Contradiction:

Improveovercurrent protectionVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines a switch and an overcurrent protection device into a single integrated unit. The switch housing contains both the switching mechanism and the overcurrent protection elements (bimetallic strip and fuse holder), allowing both functions to be performed by one device rather than requiring separate components.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The integrated switch performs multiple functions: it acts as both a manual switching device and an overcurrent protection device. The single unit provides circuit interruption through switching, thermal protection via bimetallic strip, and overload protection through fuse integration, eliminating the need for separate dedicated devices for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If separate circuit breakers or overcurrent protection devices are provided in addition to switches, then overcurrent protection is achieved, but installation complexity increases

Engineering Contradiction:

Improveovercurrent protectionVSAvoidinstallation complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines a switch and an overcurrent protection device into a single integrated unit. The switch housing contains both the switching mechanism and the overcurrent protection elements (bimetallic strip and fuse holder), allowing both functions to be performed by one device rather than requiring separate components.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If separate circuit breakers or overcurrent protection devices are provided in addition to switches, then overcurrent protection is achieved, but cost increases

Engineering Contradiction:

Improveovercurrent protectionVSAvoidcost

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines a switch and an overcurrent protection device into a single integrated unit. The switch housing contains both the switching mechanism and the overcurrent protection elements (bimetallic strip and fuse holder), allowing both functions to be performed by one device rather than requiring separate components.

Inventive Principle:

Principle #5Merging (Combining)

4Reliability

If separate circuit breakers or overcurrent protection devices are provided in addition to switches, then overcurrent protection is achieved, but space usage increases

Engineering Contradiction:

Improveovercurrent protectionVSAvoidspace usage

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent combines a switch and an overcurrent protection device into a single integrated unit. The switch housing contains both the switching mechanism and the overcurrent protection elements (bimetallic strip and fuse holder), allowing both functions to be performed by one device rather than requiring separate components.

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

This solution simplifies installations, reduces costs, and minimizes voltage drop by integrating overcurrent protection directly into the switch, enhancing safety and efficiency in low-voltage applications.

Implementation Method 1

The overcurrent protection device can include a bimetallic element configured to change shape in response to electrical current above a specified limit

Methodology Applied

Scientific EffectBimetallic element deformation: Bi-Metallic Strip

Implementation Method 2

The reset mechanism can include a spring biasing the reset plate away from the bimetallic element

Methodology Applied

Scientific EffectSpring force: Spring

Data Source

PatentUS11837426B2Switches with integral overcurrent protection components

Publication Date: 2023.12.05 MP HOLLYWOOD LLC

AI summary

Switches with integrated overcurrent protection elements are described. The overcurrent protection elements can include a bimetallic structure which is configured to move between a first shape and a second shape in response to heating. The overcurrent protection element can be rotationally coupled to a rotary knob in some embodiments. In other embodiments, the overcurrent protection element can be fixed, and the rotary knob can be connected to one or more rotatable conductive structures within the rotary switch.