Stator Coil Injection Molding for Motor Packing Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stator manufacturing methods for electric motors are inefficient due to complex and costly manual processes, incomplete coil filling, and vulnerability to dust abrasion and vibrations, leading to suboptimal performance and durability.
Innovation Solution
A method involving a stator body with coil slots wound beyond the pole horns, using baked enamel wire for mechanical stability and impregnating resin for durability, allowing for higher packing density and secure integration of coil windings, which are then stabilized using a winding template and impregnating resin.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hand-inserted pre-wound coils are used, then the coil can be pre-insulated and inserted into the stator, but the manufacturing process becomes complex and time-consuming
Solution Approach 1:
The patent replaces the mechanical hand-insertion method with an automated injection molding process. The coil is integrated directly into the stator housing through a one-step injection process, eliminating the need for manual insertion and separate insulation steps. This substitution of mechanical assembly with a unified manufacturing process resolves the contradiction between reliability and manufacturing complexity.
Solution Approach 2:
The patent merges the coil and stator housing into a single integrated component through injection molding. The coil material and stator housing material are combined in one manufacturing process, creating a unified structure that eliminates separate assembly steps. This merging resolves the contradiction by achieving both insulation reliability and manufacturing simplicity simultaneously.
2Ease of operation
If pre-wound coils are manually inserted into coil slots, then the coils can be positioned, but the coil space cannot be fully utilized due to gaps
Solution Approach 1:
The patent replaces manual coil insertion with an automated injection molding process that fills the coil space continuously. The injection process ensures complete filling of the coil cavity without gaps, as the material is forced into all available space under pressure. This substitution resolves the contradiction between ease of insertion and filling density.
Solution Approach 2:
The patent incorporates the coil directly into the stator housing during the injection molding process itself, rather than inserting it afterward. The coil material is placed and formed in its final position during the initial molding action, ensuring maximum space utilization from the start. This preliminary action eliminates the need for subsequent insertion operations and achieves complete space utilization.
3Device complexity
If air cooling is used for the electric drive, then the structure remains simple, but dust particles in the cooling air cause abrasion of the coil wire
Solution Approach 1:
The patent uses the stator housing as a protective shell that seals the coil from the external environment. The housing acts as a barrier that prevents dust particles in the cooling air from contacting and abrading the coil wire. This shell protection resolves the contradiction between simple cooling structure and protection against harmful factors.
Solution Approach 2:
The stator housing serves as an intermediary barrier between the cooling air and the coil wire. It allows cooling air to flow over the external surfaces for heat dissipation while preventing the air-borne dust particles from reaching and damaging the coil wire internally. This intermediary structure resolves the contradiction by enabling both simple cooling and protection against abrasion.
4Quantity of substance
If the coil is wound beyond the slot between pole horns, then the packing density increases, but the coil lacks mechanical support from pole horns
Solution Approach 1:
The patent merges the coil with the stator housing into a single integrated component through injection molding. The coil material is bonded to the housing material, creating a unified structure where the housing itself provides mechanical support. This merging resolves the contradiction by enabling high packing density without relying on pole horn support, as the housing becomes the support structure.
Solution Approach 2:
The stator housing acts as an intermediary support structure that replaces the traditional pole horn support function. The housing provides mechanical anchoring and structural support for the coil windings that extend beyond the slot, enabling the coil to maintain its position and withstand vibrations without direct pole horn contact. This intermediary support resolves the contradiction between high packing density and mechanical strength.
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 approach results in a compact, robust, and high-performance electric motor with improved torque and reduced size, enhanced durability against abrasion and vibrations, and efficient use of available space, while simplifying the manufacturing process.
Implementation Method 1
heating the enamel coating accordingly
Implementation Method 2
at least partially bonding the windings of the coil to each other in at least parts of the area of the coil located outside the groove
Implementation Method 3
stabilized using a winding template and impregnating resin
Data Source
Figure 1~2
Figure 3
Figure 4~5a
AI summary
The stator (10) has a stator body with a coil space for accommodating a magnet wire (20) that is in a form of a coil (20a). The coil space comprises multiple grooves, which are limited by a stator wall and pole horns (16) of the stator. The magnet wire is inserted into the coil space and wound over the grooves in a region of the coil between the pole horns. The magnet wire is formed as a partly self bonding wire. A material connection of windings of the coil one below the other is provided in parts of a coil region, which is located outside the groove. An independent claim is also included for a method for manufacturing a stator.