Sumitomo’s axial flux motor with powder magnetic core used for first time in mass-produced home air purifiers
January 19, 2024
Sumitomo Electric Industries, Ltd., headquartered in Osaka, Japan, has announced that its powder magnetic cores for axial flux motors are now being used in what is claimed to be an ‘industry-first’ flat DC motor for a home air purifier. The Humidifying Streamer Air Purifier was released by Daikin Industries, Ltd, also based in Osaka.
Daikin was able to achieve a thinner design of the flat DC motor by incorporating Sumitomo Electric’s patented double-flanged powder magnetic cores. These increase the opposing surface area between the stator and rotor while maintaining the winding space, without sacrificing performance.
Amidst the increasing demand for lighter and higher-performance motors, axial flux motors are gaining popularity due to their lighter weight, thinner shape, and higher power density, explains Sumitomo. These properties have been achieved by updating the basic structure of conventional radial flux motors. Axial flux motors outperform conventional radial flux motors in terms of output density and efficiency, particularly when the thinness of the motor is a priority. This allows for the design of thinner and lighter motors, while maintaining the same level of performance in terms of torque and maximum efficiency.
Powder magnetic cores are made by moulding and heat-treating iron powder coated with a nano-order insulating film, which exhibits excellent soft magnetic properties in the low to the high-frequency range. With the three-dimensional design flexibility, these cores are suited for use as stator cores of axial flux motors.
To further enhance axial flux motor performance, Sumitomo Electric pursued a core design that would allow for greater opposing surface area between the stator and rotor. To achieve this, the company developed a new process to press-form a powder magnetic core with a flange on each end (double-flanged powder magnetic core) as a single integrated unit.
The release of the Humidifying Streamer Air Purifier from Daikin marks the first time that Sumitomo Electric’s double-flanged powder magnetic core has been used in a mass-produced product.