Diaper Moisture Sensor Printing for Assembly Line Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing moisture sensors in diapers require manufacturing modifications and specialized printers, increasing operational complexity and costs, making them unfeasible for assembly lines.
Innovation Solution
Conductive ink sensor elements are sprayed or drawn on the inner layer of diapers using sprayers or pens during the manufacturing process, eliminating the need for specialized printers and allowing integration into existing assembly lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conductive ink based moisture sensors are printed using specialized printers, then moisture detection capability is achieved, but manufacturing complexity and operational costs increase
Solution Approach 1:
The patent extracts the moisture sensing function from complex printed circuits and implements it using simple conductive ink lines drawn directly on the diaper layer. This eliminates the need for specialized printers and complex manufacturing modifications, reducing device complexity while maintaining detection capability through the conductive ink's ability to detect moisture-induced electrical property changes
Solution Approach 2:
The patent uses inexpensive conductive ink materials that can be applied directly to the diaper layer, replacing expensive specialized printing equipment and complex sensor assemblies. The conductive ink lines serve as disposable sensing elements that are integral to the diaper structure, eliminating the need for costly specialized manufacturing infrastructure
2Reliability
If specialized printers are introduced to print conductive ink based sensors, then moisture sensing is enabled, but manufacturing time and productivity decrease
Solution Approach 1:
The patent merges the moisture sensing function with the existing diaper manufacturing process by drawing conductive ink lines directly on the diaper layer during assembly. This integration eliminates the need for separate specialized printing steps, allowing sensors to be incorporated without slowing down the overall manufacturing line and maintaining high productivity
Solution Approach 2:
The conductive ink lines are drawn on the diaper layer before final assembly, preparing the sensing elements in advance during the manufacturing process itself. This preliminary action ensures sensors are ready for use without requiring additional post-manufacturing steps or specialized equipment, thereby maintaining manufacturing speed
3Reliability
If manufacturing modifications are made to ordinary diapers, then moisture sensor functionality is achieved, but production costs and complexity increase
Solution Approach 1:
The patent makes the ordinary diaper layer itself serve multiple functions: it remains the structural component of the diaper while also serving as the substrate for the conductive ink sensing lines. This universal approach allows the same material to perform both structural and sensing functions, eliminating the need for separate specialized components and simplifying manufacturing
Solution Approach 2:
The conductive ink lines are drawn directly on the diaper layer during manufacturing, allowing the diaper structure itself to provide the sensing function without requiring external specialized equipment or complex modifications. The manufacturing process itself creates the sensors, making the system self-sufficient and simplifying production
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
Enables moisture detection and alerting without altering the manufacturing process, reducing complexity and costs while maintaining effective moisture sensing capabilities.
Implementation Method 1
a first sensor element (306a, 306b) is provided in the form of a first trace of conductive ink
Data Source
Figure 1A
Figure 1B~2
Figure 3A~4
AI summary
The present invention discloses a method of manufacturing a diaper that has multiple moisture sensing elements on interior side of its bottom impermeable layer or on any surface of the top permeable layer. The moisture sending elements are made by spraying conductive ink on a moving sheet of either the bottom impermeable layer or the top permeable layer, before other layers of the diaper are attached. Spraying of conductive ink on the moving sheet causes parallel lines of conductive inks to be formed on the layer. The parallel lines of conductive ink run through the entire length of either of the layers and are designed to get connected with a detecting device. When a user urinates inside the diaper, the moisture causes a closed circuit between at least two of the parallel lines of conductive inks. These formations of closed circuits, between parallel lines of conductive inks, are detected by the detecting device. Also, with increasing volume of moisture, the resistance of the closed circuits also tends to decrease. This rate of decrease of resistance is also detected by the detecting device and is used to calculate a volume of moisture present in the diaper. The detecting device then generates a suitable alarm to give an idea about the saturation level of the diaper. The process of manufacturing sensing elements by spraying conductive inks on moving sheet of layer reduces the processing and modification overhead of specially designed conductive ink printers and also does not impact the manufacturing time of a diaper manufacturing assembly line.