Molded Pump Motor Structure to Protect Coil Wires
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of a motor unit and a pump unit in electric pumps, where the stator is molded, often results in coil wire damage due to heat and injection pressure during the molding process, compromising waterproofness and reliability.
Innovation Solution
A pump design featuring a rotor accommodating portion within the stator assembly, with a tubular portion open to the axial direction and a stator cover that protects the coils from molten resin, ensuring the stator and rotor are separated during molding, thus preventing damage to the coil wires.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the stator is molded with resin to ensure waterproofness, then waterproofness is improved, but the coil wires are damaged by heat and injection pressure during molding
Solution Approach 1:
The stator assembly is segmented into multiple components: the stator core, coils, stator cover, and rotor accommodating portion. This segmentation allows the coils to be protected within the stator cover while the resin housing is molded around the external surfaces only, preventing direct contact between molten resin and coil wires during the molding process.
Solution Approach 2:
The stator cover acts as an intermediary protective layer between the coils and the molten resin during molding. The rotor accommodating portion with its lid and tubular structure serves as another intermediary barrier, ensuring that the resin does not directly contact the coil wires while still allowing the housing to be molded for waterproofness.
2Productivity
If the stator is molded to integrate motor and pump units, then manufacturing efficiency is improved, but dimensional accuracy of the resin housing becomes unstable
Solution Approach 1:
The stator assembly is designed as a separate pre-assembled unit containing the stator core, coils, and stator cover before being integrated into the resin housing. This segmentation allows the motor components to be manufactured and assembled independently with precise dimensional control, then integrated into the molded housing, thereby maintaining both manufacturing efficiency and dimensional accuracy.
3Device complexity
If the stator is molded directly over the coils, then integration is improved, but the coils are exposed to harmful molding conditions
Solution Approach 1:
The stator assembly is segmented into the stator core, coils, and stator cover as separate components that are assembled before housing integration. This segmentation allows the coils to be protected within the stator cover during the housing molding process, achieving integration of motor and pump units while preventing direct exposure of coils to harmful molding conditions.
Solution Approach 2:
The stator cover and rotor accommodating portion serve as intermediary protective structures between the coils and the molten resin during molding. These intermediaries allow the housing to be molded for integration purposes while shielding the coils from heat and injection pressure exposure.
Data Source
AI summary
One aspect of a pump of the present invention includes a rotor rotatable about a central axis, a stator assembly located radially outside the rotor and surrounding the rotor, a pump unit connected to a first side in an axial direction of the rotor, a support member including a rotor accommodating portion, the rotor accommodating portion being located radially inside the stator assembly and accommodates the rotor therein, and a resin housing in which the stator assembly and the support member are molded. The rotor accommodating portion includes a lid portion that covers the rotor from a second side in the axial direction, and a tubular portion that is located between the rotor and the stator assembly in a radial direction and is open to the first side in the axial direction. The stator assembly includes a stator core having an annular shape, a plurality of coils mounted on the stator core, and a stator cover that covers the plurality of coils.