Edwards Japan Limited

Katsuhisa Yokozuka

Yasushi Maejima

Yoshinobu Ohtachi

Tsutomu Takaada

Takaaki Ono

A vacuum pump, which prevents adhesion of products even when a rotating body is stopped, by heating the rotating body using an alternating current (AC) magnetic field. Two heating electromagnets are disposed facing each other across a rotating body. The heating electromagnets receive a supply of AC electric current from a heating electric power source. Excitation of the heating from this AC electric current generates an AC magnetic field. The generated AC magnetic field intersects with the rotating body. Eddy current is generated around the intersecting AC magnetic field. The rotating body is heated by this eddy current. This heating enables deposition of products to be prevented even further, and realize improved pump operation efficiency.

Vacuum pump

A vacuum pump and a washer which can reduce vibration of a rotor and the rotor which can reduce the vibration are provided. When an inertia moment ratio which is a ratio between the inertia moment around a z-axis and the inertia moment around an x-axis or a y-axis is larger than 1, a natural frequency ωdoes not match a rotational frequency Ωbut goes away from that. When the natural frequency ωmatches the rotational frequency Ω, the rotor vibrates and thus, a fatigue failure occurs in a rotor blade. When the rotor is to be made larger in a radial direction of a rotating shaft, a value of the inertia moment ratio is set to a value larger than 1.

Growing community of inventors

Yachiyo, Japan

Katsuhisa Yokozuka