Tubular Resistive Heating Element for Flexible Microfluidic Tubing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for heating small-diameter flexible tubing, such as those used in microfluidics and mass spectrometry, face challenges in maintaining flexibility and efficiency due to the interference of heating elements like tapes or cables, which can restrict the tubing's diameter and flexibility.
Innovation Solution
A heating device with a tubular body having an electrically resistive inner layer and an insulating outer layer, featuring conductive collars for electrical contact and a temperature sensor, allows for the controlled heating of small-diameter tubing by applying an electrical current through the inner layer, while maintaining flexibility and ease of use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a tape or cable comprising an encased electrical wire is used to heat the tubing, then heating capability is achieved, but the tubing's flexibility and diameter are restricted
Solution Approach 1:
The heating element is constructed as a flexible tubular structure with an inner resistive layer and outer insulating layer, allowing it to conform to and move with the tubing without restricting its flexibility or diameter, unlike rigid tapes or cables
Solution Approach 2:
The heating element transitions from a linear cable/tape configuration to a tubular three-dimensional structure that surrounds the tubing, providing heating capability while maintaining tubing flexibility and allowing fluid flow through the center passage
2Temperature
If a heating element is applied to small-diameter tubing, then heating function is provided, but the device complexity increases
Solution Approach 1:
The heating element combines multiple functions into a single integrated tubular structure: the inner layer provides resistive heating, the outer layer provides electrical insulation, and the passage allows fluid flow, eliminating the need for separate heating cables, insulation wraps, and mounting hardware
Solution Approach 2:
The tubular heating element serves multiple purposes simultaneously: it heats the tubing through resistive heating, insulates electrically to prevent short circuits, maintains tubing flexibility, and allows fluid passage through its center, making it a universal solution for heating small-diameter tubing
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 solution effectively heats and regulates the temperature of small-diameter tubing, ensuring flexibility and ease of installation in applications like microfluidics and mass spectrometry, by using a braided carbon fiber sleeve as the resistive material and a heat-shrinkable sheath for insulation, allowing for precise temperature control and repeated use without damaging the tubing.
Implementation Method 1
The inner layer is electrically resistive... applying an electrical current to the inner layer increases the temperature of the inner layer
Implementation Method 2
The outer layer is electrically insulating
Data Source
Figure 1
Figure 2
Figure 3~6
AI summary
Heating devices, systems, and methods of making and using a heating device. Such a heating device includes a tubular body having a passage therethrough, at least an inner layer surrounding the passage, and an outer layer surrounding the inner layer. The inner layer is electrically resistive and the outer layer is electrically insulating, and the passage is sized and configured to receive therethrough a tubing. The heating device further includes electrical contacts located at oppositely-disposed ends of the tubular body. The contacts are configured to functionally couple with a power source to provide an electrical current to the inner layer, such that applying an electrical current to the inner layer increases the temperature of the inner layer.