Heated Flow Line with Outer Wires and Heat-Shrink Sheath
Solution Overview
Problem
Existing heated flow lines for motor vehicle fluid-feeding systems face issues such as electric wire surfacing, material contamination, rapid wire deterioration, increased production costs, interface failure risks, and inflexible production processes due to embedded electric wires within plastic pipes, especially during deformation and connector fitting.
Innovation Solution
A heated flow line design where electric wires are arranged on the outer surface of a plastic pipe with a heat-shrinkable sheath that compresses and secures the wires, allowing for sliding and deformation while maintaining a reliable electrical connection, and enabling easy modification of wire configuration and length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If electric wires are embedded within the plastic pipe via extrusion, then the heating function is achieved, but the electric wires may surface inside the pipe causing fluid contamination and rapid wire deterioration
Solution Approach 1:
The electric wires are extracted from the interior of the pipe and positioned on the outer surface. The sheath material is applied over the pipe and wires, then heat-shrunk to enclose the wires externally while maintaining the pipe's interior cleanliness and preventing wire deterioration from fluid exposure.
Solution Approach 2:
The structure is organized in nested layers: the plastic pipe forms the inner core, electric wires are nested on the outer surface of the pipe, and the heat-shrunk sheath material is nested over both, creating a protected composite structure where each layer serves its specific function.
2Object-affected harmful factors
If a greater amount of plastic material is used to prevent wire surfacing, then fluid contamination is prevented, but production costs increase considerably
Solution Approach 1:
By extracting the wires from the interior to the exterior surface, the patent eliminates the need to use excessive plastic material to embed and secure the wires internally. The sheath material provides securement without requiring increased pipe wall thickness or material quantity.
Solution Approach 2:
The heat-shrunk sheath material acts as an intermediary that secures the electric wires to the pipe's outer surface without requiring additional plastic material in the pipe itself. This mediator provides the necessary mechanical attachment while keeping the pipe's material usage optimized.
3Reliability
If electric wires are embedded within the pipe, then heating is achieved, but the plastic/electric-wire interface has increased failure risk during deformation
Solution Approach 1:
The electric wires are taken out from the pipe's interior and positioned on the outer surface, eliminating the plastic/electric-wire interface that is prone to failure during deformation. The wires are instead secured to the pipe's exterior where they can accommodate deformation more effectively.
Solution Approach 2:
The heat-shrunk sheath material provides a dynamic attachment that allows the electric wires to move and deform with the pipe rather than being rigidly fixed. This dynamic securing method maintains the heating function while accommodating the pipe's deformation during installation and use.
4Reliability
If the pipe is formed with electric wires already arranged on it, then the heating configuration is fixed, but production process management and warehousing become enormously complicated
Solution Approach 1:
The heating system is segmented into separate components: the pipe and the electric wires are independent elements that are assembled together through the heat-shrunk sheath. This segmentation allows the pipe to be produced and stored separately from the wire configuration, enabling flexible production and simplifying warehousing while maintaining stable heating performance through standardized assembly.
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 design enhances versatility and durability by allowing deformation and varied use conditions, reducing mechanical stress, and simplifying production and warehousing, while maintaining effective heating performance without additional insulation layers.
Implementation Method 1
a sheath (5) made of heat-shrinkable material... applied via a heat-shrinking process on the outer surface of the pipe (2) on which the wires (3, 4) have previously been arranged
Implementation Method 2
generate, when subjected to a difference of electric potential, an electric current within said pipe... the pipe made of plastic material with positive temperature coefficient
Implementation Method 3
pipe made of plastic material with positive temperature coefficient... its electrical resistance, and hence its heating capacity, substantially decreases above a given temperature threshold, and it is thus capable of self-regulation
Data Source
Figure 1~2
AI summary
Described herein is a heated flow line for a fluid-feeding system of a motor vehicle, comprising: - a pipe (2) made of plastic material with positive temperature coefficient; and - at least one first electric wire (3) and one second electric wire (4) electrically associated to said pipe (2) in such a way as to generate, when subjected to an electric potential, an electric current within said pipe, in a part thereof without said electric wires, according to a direction from said first wire to said second wire, or vice versa. The flow line is characterized in that said first and second wires (3, 4) are arranged on the outer surface of said pipe (2) and in that it comprises a sheath (5) that coats at least part of said outer surface and presses said first and second wires (3, 4) against said surface.