Inductive Pressure Switch for Washer Load and Vibration Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing detection systems for household appliances with mobile components, such as washing machine tanks or baskets, fail to accurately measure static load (weight) and are bulky, difficult to assemble, and costly, while also struggling to detect vibrations effectively.
Innovation Solution
A compact, low-cost pressure switch system with a deformable membrane and ferromagnetic core, coupled with a variable inductance electrical inductor, is integrated with a ferromagnetic bracket and electronic circuit to detect hydraulic pressure, vibrations, and weight, using a clearance-based mechanism to generate electrical signals for both static and dynamic conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a pressure switch with a mobile stop defined by a spring is used to detect hydraulic pressure and vibrations, then the system can detect basket vibrations, but the device becomes relatively large in size, difficult to assemble, and has high production cost
Solution Approach 1:
The patent combines the stop function and the ferromagnetic element function into a single integrated bracket carried by the load-bearing frame. This bracket serves both as the mechanical stop that defines the zero position and as the ferromagnetic element that interacts with the inductor for vibration detection, eliminating the need for separate components and reducing overall device complexity
Solution Approach 2:
The bracket is designed to perform multiple functions: it acts as the structural support for the pressure switch, provides the mechanical stop for zero position definition, and serves as the ferromagnetic element for vibration detection through its interaction with the variable inductance inductor. This multi-functionality reduces the number of components needed
2Reliability
If a pressure switch with a mobile stop defined by a spring is used, then vibration detection is enabled, but production cost increases
Solution Approach 1:
By merging the stop and ferromagnetic element into a single bracket, the patent reduces the number of parts that need to be manufactured and assembled, thereby lowering production costs while maintaining vibration detection capability
Solution Approach 2:
The patent extracts the essential function of vibration detection from the complex mobile stop mechanism and implements it through a simpler ferromagnetic bracket interacting with a variable inductance inductor, reducing manufacturing complexity and cost
3Reliability
If the existing pressure switch system is used, then hydraulic pressure detection is achieved, but static load (weight) detection is not possible and must be set manually by the user
Solution Approach 1:
The pressure switch is designed to perform multiple detection functions: it detects hydraulic pressure through the membrane, detects static load (weight) through the variable inductance inductor's interaction with the ferromagnetic bracket, and detects vibrations through the same inductor-bracket interaction. This multi-functionality eliminates the need for manual weight setting by the user
Solution Approach 2:
The ferromagnetic bracket acts as an intermediary element that translates mechanical position changes (caused by both pressure and weight variations) into magnetic field changes that affect the variable inductance inductor, enabling indirect detection of both pressure and weight parameters
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
The system allows precise detection of weight and vibrations, ensuring load balance with minimal size and production costs, enhancing operational reliability and ease of assembly.
Implementation Method 1
a deformable membrane sensitive to hydraulic pressure
Implementation Method 2
a winding fastened to the casing and operatively coupled to the core to form a variable inductance electrical inductor; the pressure switch is adapted to output an electrical signal in response to a variation of the clearance induced by a relative movement between bracket and casing
Implementation Method 3
a ferromagnetic material core fastened to the membrane and a winding carried by the casing and operatively coupled to the core
Data Source
Figure 1~3
Figure 2~4
AI summary
A system for detecting the operative parameters of a household appliance, such as a washing machine or dryer, provided with a relatively mobile component (3) with respect to a load-bearing frame (tank or basket) , including a pressure switch (10) including in turn a rigid casing (11) accommodating a deformable membrane (13) sensitive to hydraulic pressure, a ferromagnetic material core (14) engaged to the membrane and a winding (15) fixed to the casing and operatively coupled with the core to form a variable inductance electrical inductor (16) ; in which the pressure switch (10) is coupled to the relatively mobile member (3) to follow its movements; and in which said variable inductance electrical inductor (16) is operatively associated to a ferromagnetic material bracket (40) integrally carried by the load- bearing body and arranged outside the pressure switch (10) .