Bladeless fan

A bladeless fan (sometimes called an air multiplier) blows air from a ring with no external blades. Its blades are hidden in its base. The first concept was created by Toshiba in 1981.Dyson claims that its bladeless fans (U.S. Patent 8,454,322) produce a more constant airflow than traditional fans.

The air is drawn in by a turbine in the base and then directed up into a ring. It comes out of a crack all around the ring and passes over a shape like that of an aircraft wing. Industrial designer Sir James Dyson named his fan the Air Multiplier.

Dyson sued Chinese companies because they began selling bladeless fans for much less than Dyson.

In 2015, Panasonic announced a spherical bladeless fan. It is a bladeless fan that is spherical in shape and takes in air through one side and blows it out the other.

There are no visible moving blades in this fan. The blade is hidden inside the pedestal of the fan. In 2009 James Dyson first introduces a new innovation in the bladeless fan by adding air-multiplier technology. This Dyson air-multiplier fan generates airflow up to 55mph. The fan contains a brushless electric motor and this motor rotates nine asymmetrical aligned blades that attach with a rotor. Usually, the upper frame of this fan is ring shaped. The frame is not flat; rather it is manufactured such that the edge can create a curve of a 16-degree angle slope. The air flows through the channel in the pedestal of the fan when the motor is turned on. After that, the air flows through the hollow tube. Then the air is shot out through 16-mm slits. This air flows smoothly, rather than turbulently as with a blade fan. The curvature of the inner wall of the fan creates an area of negative pressure - like an airplane wing - to draw more air into the flow, hence "multiplying" it. This property of the air is called inducement. Further, the air surrounding the edges of the fan also begins to flow with the direction of the breeze, or is "entrained" to it. Dyson fan manufacturer Jameco Electronics claims that the air-multiplier technology increases the output of the air flowing through the tube by 15 times or more the airflow of a traditional bladed fan. The engineers of Jameco Electronics tested that the fan can blow 300 liters of air per second.

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Wikipedia