Synchronous Motor Pump Heating Control Without Fluid Sensors
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Solution Overview
Problem
Existing fluid circulation pumps in washing machines and dish-washing machines rely on temperature and pressure sensors to control heating elements, which are delicate, prone to malfunction, and costly to replace, often requiring the entire pump to be replaced when sensors fail.
Innovation Solution
A synchronous-motor fluid circulation pump that detects fluid temperature and flow rate using a control unit with an analogue Hall sensor, eliminating the need for temperature and pressure sensors by cutting off the resistance electric supply when predetermined critical values are reached, thereby avoiding sensor-related issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If temperature and pressure sensors are used to control heating elements, then heating control is achieved, but the system becomes unreliable and costly due to sensor malfunction
Solution Approach 1:
The patent extracts and eliminates the temperature and pressure sensors from the heating control system. Instead of using sensors to detect fluid conditions and control the heating element, the system uses the motor's own operational parameters (current, voltage, speed) to indirectly infer fluid temperature and flow conditions, thereby removing the unreliable sensor components while maintaining heating control functionality
Solution Approach 2:
The motor serves multiple functions: it not only drives the pump but also acts as an indirect sensor for fluid temperature and flow rate detection. By monitoring the motor's electrical characteristics and operational behavior, the system gains temperature and flow information without requiring dedicated sensing components, thus achieving multi-functionality with the existing motor
2Productivity
If large resistances are used for fast heating, then heating speed is improved, but the risk of overheating and damage increases
Solution Approach 1:
The system implements continuous feedback monitoring of the motor's operational parameters (current, voltage, speed) which correlate with fluid temperature and flow conditions. This feedback loop allows the control system to adjust the heating element power in real-time, maintaining fast heating when fluid flow is adequate while automatically reducing or cutting power when temperature reaches critical levels or flow decreases, thus preventing overheating damage
Solution Approach 2:
The heating control system dynamically adjusts the heating element power based on real-time motor operational conditions. Rather than using fixed high power resistance heating, the system modulates the heating power according to fluid flow rate and temperature inferred from motor behavior, enabling fast heating during normal operation while dynamically preventing overheating when conditions change
3Ease of operation
If temperature and pressure sensors are installed in the pump, then heating control is enabled, but maintenance cost increases due to sensor replacement
Solution Approach 1:
The patent removes the temperature and pressure sensors from the pump system entirely. Heating control operation is achieved by monitoring the motor's electrical and mechanical parameters, which provide indirect but sufficient information about fluid temperature and flow conditions, eliminating the need for sensor installation and subsequent replacement
Solution Approach 2:
The motor effectively monitors its own operational state and provides information about fluid conditions through its electrical characteristics. The control system uses this self-provided information to manage heating control, eliminating the need for external sensing components that would require maintenance and replacement
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 allows for reliable and cost-effective control of fluid heating, reducing the risk of overheating and damage, and simplifying the maintenance process by eliminating the need for temperature and pressure sensors.
Implementation Method 1
A synchronous-motor fluid circulation pump that detects fluid temperature and flow rate using a control unit with an analogue Hall sensor
Implementation Method 2
heating means of the fluid, generally composed of resistances
Data Source
AI summary
A fluid circulation pump (10) with synchronous motor (14), equipped with fluid heating device (40), particularly for washing machines or the like, of the type comprising a rotor (18), equipped with a permanent magnet being rotation-driven by the electromagnetic field generated by a stator (15) equipped with pole shoes (20) with the corresponding windings. This pump (10) has also a magnetic flux sensor (22) of the rotor (18) and a control unit (24) a signal from the magnetic flux sensor (22) at least a typical parameter of said fluid and a comparator this parameter with a reference value and to cut the power supply of the fluid heating device (40) off upon reaching a threshold of the predetermined reference parameter.