Steam Iron Water Detection via Soleplate Temperature Monitoring
Solution Overview
Problem
Steam ironing apparatuses lack an effective and cost-efficient method to detect when the water tank is empty, which can lead to the motor pump running dry, causing overheating and reducing its lifespan.
Innovation Solution
A temperature sensor is used in thermal contact with the soleplate to evaluate the signal progression of the temperature signal after the motor pump is activated, determining if there is a cooling effect, indicating the presence of water in the tank, thus preventing the motor pump from running dry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a level sensor is arranged in the water tank to detect water level, then the detection reliability is improved, but the device complexity increases
Solution Approach 1:
The temperature sensor serves dual functions: monitoring the soleplate temperature for ironing control and detecting water presence in the water tank. When water is present, it absorbs heat from the soleplate causing temperature to drop; when absent, temperature remains stable or rises. This eliminates the need for a separate level sensor while maintaining detection reliability.
Solution Approach 2:
The system uses its own temperature monitoring infrastructure to perform water level detection. The temperature sensor and control unit that already exist for thermal management are repurposed to detect water presence, making the existing system serve an additional function without requiring external detection devices.
2Productivity
If an electromagnetic valve and pump control system is added to automatically replenish water, then the productivity is improved, but the device complexity increases
Solution Approach 1:
The control unit performs multiple functions: temperature control, water level detection, and automatic water replenishment control. By integrating these functions into a single control unit that already manages the heating element and temperature sensor, the system achieves automated operation without adding complex control infrastructure.
Solution Approach 2:
The control logic for temperature management and water replenishment is merged into a single control unit. The same control unit that regulates heating element operation also manages pump activation and electromagnetic valve control for water replenishment, consolidating control functions rather than separating them into distinct control systems.
3Device complexity
If the motor pump runs dry without detection, then the device complexity remains low, but the reliability deteriorates due to overheating and reduced lifespan
Solution Approach 1:
The system continuously monitors soleplate temperature as feedback to determine water presence. When the temperature sensor detects abnormal temperature patterns indicating no water flow (stable or rising temperature instead of expected drop), the control unit responds by shutting down the pump, preventing dry running and overheating while maintaining system reliability.
Solution Approach 2:
The patent converts the thermal effect of water cooling (which is necessary for steam generation) into a detection mechanism. The same heat transfer that cools the soleplate during normal operation becomes the signal for detecting water presence, turning a functional process into a diagnostic tool that prevents pump damage.
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 allows for simple and low-cost detection of an empty water tank, preventing motor pump overheating and extending its lifespan by providing an indication or shutting down the pump when the tank is empty.
Implementation Method 1
a temperature sensor disposed in thermal contact with the soleplate, the temperature sensor being adapted for generating a temperature signal in dependence on the temperature of the soleplate
Implementation Method 2
a heating element disposed in thermal contact with the soleplate, the heating element being adapted for heating the soleplate
Implementation Method 3
a water tank in fluidic connection with a motor pump, the motor pump being adapted for supplying water to the steam chamber for generating steam
Implementation Method 4
the motor pump being adapted for supplying water to the steam chamber for generating steam
Data Source
Figure 1
Figure 2a~2b
Figure 3
AI summary
A steam ironing apparatus is described. The steam ironing apparatus comprises a soleplate with a plurality of steam outlet ports configured for emitting steam, a heating element disposed in thermal contact with the soleplate, the heating element being adapted for heating the soleplate, and a water tank in fluidic connection with a motor pump, the motor pump being adapted for supplying water to the soleplate for generating steam. The steam ironing apparatus further comprises a temperature sensor disposed in thermal contact with the soleplate, the temperature sensor being adapted for generating a temperature signal in dependence on the temperature of the soleplate, and a control unit. The control unit is adapted for evaluating, upon activation of the motor pump, a subsequent signal progression of the temperature signal and for deriving from said signal progression whether or not there is water in the water tank.