Household washing machine
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing devices for determining the salinity concentration of brine in household washing machines are complex, expensive, and prone to reduced precision due to vibrations and require precise geometry, making them time-consuming and inefficient for detecting salinity levels accurately.
Innovation Solution
A household washing machine equipped with an electro-optical sensor assembly that includes a plug frame with an emitting device and a receiving device, optically coupled via a waveguide body, which determines salinity by measuring the refraction index of the brine, providing a stable and cost-effective solution for salinity detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a float-based optical detection device is used to detect salinity concentration, then the detection function is provided, but the device complexity increases and assembly becomes time-consuming due to precise positioning requirements
Solution Approach 1:
A waveguide element is introduced as an intermediary between the optical emitter and receiver. The waveguide extends into the brine container and its outer surface acts as the optical interface with the brine, eliminating the need for precise positioning of emitters and receivers relative to the container walls. The waveguide mediates the optical interaction while being easily attachable to the container.
Solution Approach 2:
The mechanical positioning system (float, precise emitter-receiver alignment) is replaced with an optical waveguide system. The waveguide's physical presence in the brine provides the optical interface, substituting complex mechanical alignment requirements with a simpler waveguide attachment to the container.
2Measurement precision
If precise geometry and positioning of optical components are required, then detection accuracy is maintained, but manufacturing and assembly become more difficult and time-consuming
Solution Approach 1:
The waveguide serves as a mediator that decouples the optical components (emitter and receiver) from the brine container walls. Instead of requiring precise positioning relative to the container, the waveguide is simply attached to the container and extends into the brine, providing a stable optical interface that is easy to manufacture and assemble.
Solution Approach 2:
The detection system is segmented into separate functional components: the waveguide element (optical interface), the optical emitter, and the optical receiver. This segmentation allows each component to be optimized independently and assembled in a straightforward manner without requiring complex overall geometry.
3Ease of operation
If the optical emitter and receiver are positioned outside the brine container, then the optical path can be established, but vibrations reduce detection precision
Solution Approach 1:
The waveguide is nested within the brine container structure, with its outer surface immersed in the brine while the emitter and receiver remain outside. This nested configuration provides a stable optical interface that is protected from vibrations, as the waveguide's position relative to the container (and thus the brine) remains stable during operation.
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 electro-optical sensor assembly accurately and efficiently determines the salinity of the brine, reducing the need for precise assembly and minimizing the impact of vibrations, allowing for continuous salinity measurement and optimal regeneration of ion-exchange resins, thus enhancing the washing machine's performance and user experience.
Implementation Method 1
an electro-optical sensor configured to determine the salinity of the brine contained in said brine tank by measuring a refraction index of the brine
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
A household washing machine (1)(100) comprising: an outer casing (2), a washing tub (3)(103) which is placed inside said outer casing (2), an internal water softening device (13)(110), a brine tank (45)(111) containing brine for regenerating the water softening device (13)(110), a sensor assembly (69) which is provided with an electro- optical sensor (70)(170)(270) configured to determine the salinity of the brine contained in the brine tank (45)(111), the electro-optical sensor (70)(170)(270) comprises: a plug frame (71) which is fitted into an opening (45a) formed on a wall of the brine tank (45)(111), optical interface elements (75)(87a,88a)(98a,98b) associated with the plug frame (71) and shaped in order to be at least partially in contact with the brine, an emitting device (72) a receiving device (73) stably incorporated/placed in the plug frame (71) in respective prefixed positions, one to the other, with respect to optical interface elements (75)(87,88)(98a,98b), and electronic control device (74) which is configured to receive an electrical signal from the receiving device (73) being indicative of the refraction index of the brine and determine the salinity of the brine on the basis of determined refraction index.