Peltier Element Safety Testing via Thermoelectric Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Peltier elements in small electrical appliances, such as electric shavers, are prone to mechanical or thermal damage, leading to malfunction and potential user safety issues due to changes in internal resistance and cooling performance, which can result in overheating and burns.
Innovation Solution
A method involving the application of voltage to a Peltier element for a specified period, followed by voltage measurement and comparison with a reference value, using a safety device with a microcontroller to assess the thermoelectric voltage and trigger safety measures if the element is defective, ensuring user protection by preventing appliance usage when the element is faulty.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a Peltier element is used for cooling the skin during shaving, then user comfort is improved, but the risk of overheating and burns increases if the element malfunctions
Solution Approach 1:
The patent applies preliminary action by performing a safety test before the actual shaving operation. The control circuit applies a test voltage to the Peltier element, measures the resulting thermoelectric voltage, and compares it against reference values to detect defects before the element is used for cooling, thereby preventing potential overheating and burns while maintaining user comfort
2Duration of action of stationary object
If the Peltier element operates continuously, then cooling performance is maintained, but the element may be destroyed by mechanical or thermal effects
Solution Approach 1:
The patent implements feedback by continuously monitoring the thermoelectric voltage of the Peltier element during operation. The control circuit measures the voltage generated by the element and compares it against reference values, providing real-time feedback that allows the system to detect degradation or damage and adjust or terminate operation to prevent element destruction while maintaining cooling performance
3Reliability
If a safety test is performed before operation, then user safety is improved, but the testing time and complexity increase
Solution Approach 1:
The patent applies partial action by performing a simplified safety test that uses only a brief voltage application and measurement of thermoelectric voltage, rather than comprehensive testing procedures. This partial testing approach provides sufficient safety assurance while minimizing the time lost before the appliance can be used for its intended cooling function
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 method provides a rapid and reliable means to test Peltier elements, ensuring user safety by preventing the use of defective elements and maintaining the appliance's cooling performance, thereby preventing overheating and ensuring the safety of the user during operation.
Implementation Method 1
a voltage is applied to the Peltier element for a certain period of time... a temperature difference arises between the cold side of the Peltier element and the warm side of the Peltier element
Implementation Method 2
after the voltage is switched off a thermoelectric voltage which corresponds to this temperature difference will be measurable at the Peltier element
Data Source
Figure 1
Figure 2
AI summary
A method with the following steps is described for testing a Peltier element: - applying a voltage to the Peltier element, - switching off the voltage at the end of a defined period of time, - measuring the voltage at the Peltier element and - comparing the measured voltage with a reference value. Furthermore, a small electrical appliance (for example an electric shaver) with a Peltier element is described, which small electrical appliance has a safety device which ensures that a malfunction of the Peltier element cannot result in danger to the user.