Emergency Lighting Circuit Brightness Control via Switch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing emergency lighting systems lack the ability to adjust brightness, resulting in inconsistent luminaire brightness during different working conditions and require users to adjust drive current to extend battery life, which complicates the system and reduces working time.
Innovation Solution
A circuit that includes an AC/DC converter, an AC input detection module, a switching time detection module, and a battery protection management module, allowing the system to control the brightness of emergency lighting luminaires by changing the current limiting resistor of the LED load through a switch, enabling dimming functionality without increasing system complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed drive current is used for emergency lighting, then the circuit is simple, but the lighting brightness cannot be adjusted and working time is limited
Solution Approach 1:
The patent applies the dynamics principle by making the drive current adjustable rather than fixed. A switch is added to the circuit that allows users to select between different current paths: one path provides full drive current for maximum brightness, while another path includes a current limiting resistor that reduces the drive current to extend battery life. This dynamic adjustment capability resolves the contradiction between circuit simplicity and extended working time.
2Duration of action of moving object
If the drive current is reduced to extend battery life, then the working time is prolonged, but the lighting brightness decreases
Solution Approach 1:
The patent implements dynamics by providing a switchable circuit configuration that allows users to dynamically adjust between two operating modes: high brightness mode with shorter battery life, and reduced brightness mode with extended battery life. The switch enables selection of different current paths through the LED load, with one path containing a current limiting resistor to reduce drive current and extend working time, while the other path provides full current for maximum brightness.
3Duration of action of moving object
If users can adjust drive current to extend working time, then the working time is prolonged, but the system complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the current path into separate controllable segments. The circuit is segmented into two parallel current paths: one path goes directly from the power source to the LED load, while the other path includes a current limiting resistor. A switch controls which path is active, allowing users to select between full brightness and extended working time modes. This segmented approach adds minimal complexity while achieving the desired functionality.
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
Enables adjustable brightness of emergency lighting luminaires, extending their working time by allowing users to customize lighting according to needs while maintaining system simplicity.
Implementation Method 1
An AC/DC converter is configured to convert the AC network voltage to a DC voltage
Implementation Method 2
The LED load is connected to ground after connecting a resistor R1 in series
Data Source
AI summary
A circuit includes an emergency lighting system and an AC/DC converter. An output terminal of the emergency lighting system is electrically connected to a LED load, and the other output terminal DIM of the emergency lighting system is electrically connected to a switch S2. The switch S2 is controlled by the emergency lighting system. The emergency lighting system includes an AC input detection module, a switching time detection module and a lithium battery. The AC input detection module is electrically connected to a neutral wire VN and a live wire VL. The switching time detection module is electrically connected between an output terminal of the AC input detection module and the terminal DIM. An output terminal of the AC/DC converter is electrically connected to a positive electrode of the lithium battery, and the other output terminal of the AC/DC converter is electrically connected to the LED load.