Temperature Threshold Detection Using Variable Resistance and Pulse Current
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing temperature monitoring devices for heat sources, such as battery cells, lack the ability to adjust the temperature threshold post-manufacture and result in abrupt disconnection without corrective measures, as they rely on a single adjustable parameter during manufacturing.
Innovation Solution
A device with components having variable electrical resistance based on operating temperature, using an electrical power source to deliver current in the form of periodic pulses, allowing for adjustable temperature thresholds and enabling detection and corrective actions for heat sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a mechanical switch with a temperature-sensitive plate is used for temperature monitoring, then the device structure is simple, but the temperature threshold cannot be adjusted after manufacture
Solution Approach 1:
The patent replaces the mechanical temperature-sensitive plate and mechanical switch system with an electrical system using a current source, resettable fuse, and microcontroller. The microcontroller monitors temperature via the resettable fuse's resistance changes and controls the charging circuit electronically, enabling software-configurable temperature thresholds that can be adjusted after manufacture without mechanical modifications.
Solution Approach 2:
The patent introduces dynamic adjustability of the temperature threshold through software configuration in the microcontroller. The threshold can be dynamically changed based on different operating conditions, battery states, or user requirements, transforming the static mechanical threshold into a dynamic programmable parameter.
2Ease of manufacture
If a mechanical switch with fixed threshold is used, then the device is simple to manufacture, but corrective measures cannot be taken before abrupt disconnection
Solution Approach 1:
The patent implements a feedback system where the microcontroller continuously monitors the temperature through the resettable fuse's resistance changes and compares it against the programmed threshold. When the threshold is approached, the system can provide feedback warnings and gradually reduce charging current or take corrective measures before abrupt disconnection occurs, improving reliability and safety.
Solution Approach 2:
The system takes preliminary action by detecting temperature trends and providing warnings before the critical threshold is reached. The microcontroller can initiate corrective measures such as reducing charging current or alerting the user in advance, preventing abrupt disconnections and allowing gradual response to temperature increases.
3Adaptability or versatility
If periodic current pulses are used to heat the component, then the temperature threshold can be adjusted via duty cycle, but the device complexity increases
Solution Approach 1:
The microcontroller serves multiple functions: it monitors temperature through the resettable fuse, generates periodic current pulses with adjustable duty cycle, controls the charging circuit, and provides user interface management. This multi-functionality reduces the need for separate dedicated circuits for each function, thereby limiting the increase in overall device complexity while achieving programmable temperature threshold adjustment.
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 dynamic adjustment of temperature thresholds without physical changes to the device, providing reliable detection and corrective actions for heat sources, improving monitoring and management of battery cell temperatures.
Implementation Method 1
at least one component having an electrical resistance that is variable depending on an operating temperature of the component
Implementation Method 2
the heat given off by Joule heating in the component when the electrical current flows therethrough
Data Source
AI summary
A device and method for detecting when at least one heat source exceeds a temperature threshold. The device includes a component having an electrical resistance that varies according to the operating temperature of the component, and an electrical power source suitable for supplying an electrical current to the component. The component is configured to be thermally coupled to the heat source, such that the operating temperature varies according to the temperature of the heat source and the heat released in the component by the Joule effect, the variable electrical resistance having a high value if the operating temperature is greater than a triggering threshold, the electrical power source being configured to generate the electrical current such that the operating temperature is greater than or equal to the triggering threshold once the temperature of the heat source is greater than or equal to the temperature threshold.