Low-noise, low-power-consumption motor for air purifiers
- Make a quiet, power-saving, and high-efficiency air purifier.
- Contra-rotating propeller fan with high quiet performance and low-power consumption
Win the 2021 Energy Conservation Grand Prize for our contra-rotating propeller fan.
While demand for air purifiers has been growing in recent years, there seem to be many cases in reality where they are not used at the maximum wind force due to concern over such issues as power consumption and noise. This is why Zojirushi Corporation debuted Air Purifier PU-AA50, which boasts high quiet and energy-saving performances. Consuming only 10W, or approximately 20% of its rival products of the same class, and operating at 39dB, which is quieter than inside a library (app. 40dB), this product won the Energy Conservation Center, Japan Chairman’s Award in the Product and Business Model Section of the 2021 Energy Award hosted by Energy Conservation Center, Japan.
Part of the key to realizing the aforementioned quiet performance and low power consumption was Nidec’s contra-rotating propeller fan. The technology used in it applies the contra-rotating propeller, which is used in aircraft propellers and ship screws, and rotates two, respectively optimized fans in the reverse direction from each other to generate aerial current efficiently.
So far, Nidec has utilized this technology for its server-cooling fans. While strong cooling systems are required for servers, whose heating values are increasing every year, there is only so much space to install fans. This is why the contra-rotating propeller fan proved to be an effective solution for efficient cooling of servers. Air Purifier PU-AA50 utilizes this technology, which Nidec has cultivated in this area of server cooling.
Applying technology cultivated in server cooling
The contra-rotating propeller fan has a merit of delivering wind straight and far away. A single propeller alone would only cause the wind to rotate and disperse; however, with another propeller, the fan collects the circling portion of the wind to generate a straight, far-reaching wind. On the other hand, though, with two propellers rotating, the noise from such a fan in general tended to become larger. Thus, in some datacenters, where numerous servers operate and numbers of cooling fans rotate, noise would become so loud that people could not work in them for a long time. To address this noise issue, Nidec created a certain cross-sectional shape and rpm for the fan’s two propellers, and developed technology to successfully eliminate the noise from the fan, and enhance its quiet performance.
Air Purifier PU-AA50 utilizes this technology, which enables the front propeller to deliver an easy-to-catch wind to the back propeller, achieving high efficiency and quiet performance. The air purifier was designed to have an appropriate airflow path to accommodate a filter, an essential element of the product. Nidec’s high-efficiency motor equipped in Air Purifier PU-AA50 makes it a highly energy-efficient product as well.
To realize Zojirushi Corporation’s aspiration of making the world’s best air purifier, the company and Nidec adapted a contra-rotating propeller fan, which had hardly been used for air purifiers, designed an optimum airflow path, and used a high-efficiency motor to jointly develop Air Purifier PU-AA50.