Mitsubishi Denki Kabushiki Kaisha

Toshio Tatsutani

Tetsuya Tanaka

Toshihiko Horii

Yuzi Serizawa

Tatsuo Yamasaki

Ryohei Uchida

Ippei Hagiwara

Keiu Kawasaki

Toshio Idei

Masaaki Sendo

Keiichi Hasegawa

Yoshiyuki Umai

Kazuhiko Hotta

A hand dryer in which a channel-like hand insertion unit 5 opening at the front face and side faces is formed in the front face of a case 6 which functions as an outer shell. Upper and lower blowout nozzles 32 and 33 are disposed in the upper and lower faces of the hand insertion unit 5. A high-pressure air flow generation device 7 supplies high-pressure air flow to the blowout nozzles 32 and 33. A high-speed wind generated in the hand insertion unit 5 blows water on hands to the inner portion of the hand insertion unit 5. The blown water is drained to the outside of the hand insertion unit 5, through drainage holes 18 which are disposed at lateral ends of the bottom face of the hand insertion unit 5. Thereby, the blown water from the hands can be smoothly drained without remaining in the hand insertion unit.

Hand dryer

An electric motor used for example in a magnetic disk drive, comprises a rotor having a hub on which the magnetic disk is mounted, and an annular driving permanent magnet, and rotating together with a rotary shaft, and a stator disposed outside the rotor, having a core and coils wound on the core. A signaling permanent magnet for detecting the rotary angle or the rotational speed of the rotor may be provided on the radially inner side of the driving permanent magnet. Part of the outer periphery of the stator core may be retracted radially inward or cut away to form a concavity or an open part. A magnetic shielding plate may further be provided to cover the coils, with part or the entirety of the magnetic shielding plate being positioned closer to the rotary shaft than the outermost periphery of the rotor to prevent the escape of the rotor in the direction of the rotary shaft. The stator core may be provided, at its inner extremities, bent portions extending in the direction parallel with the rotary shaft, and away from the hub. Alternatively, the midpoint of the stator core may be positioned farther away from the hub than the midpoint of the driving permanent magnet.

Electric Motor

An electric motor used for example in a magnetic disk drive, includes a rotor having a hub on which the magnetic disk is mounted, and an annular driving permanent magnet, and rotating together with a rotary shaft, and a stator disposed outside the rotor, having a core and coils wound on the core. A signaling permanent magnet for detecting the rotary angle or the rotational speed of the rotor may be provided on the radially inner side of the driving permanent magnet. Part of the outer periphery of the stator core may be retracted radially inward or cut away to form a concavity or an open part. A magnetic shielding plate may further be provided to cover the coils, with part or the entirety of the magnetic shielding plate being positioned closer to the rotary shaft than the outermost periphery of the rotor to prevent the escape of the rotor in the direction of the rotary shaft. The stator core may be provided, at its inner extremities, bent portions extending in the direction parallel with the rotary shaft, and away from the hub. Alternatively, the midpoint of the stator core may be positioned farther away from the hub than the midpoint of the driving permanent magnet.

Electric motor

A control apparatus of a transistor motor comprises an addition reference setting circuit (203), a positive voltage addition circuit (204 and 207), a negative voltage addition circuit (205), and a positive/negative voltage addition circuit (202). The addition reference setting circuit (203) is adapted to produce reference values VC and VD. The addition is made of the magnitude of the positive-going component with respect to the reference value VC out of the peak values of the feedback voltages (VU, VV and VW) in the positive voltage addition circuit, whereby the output VAA is provided. Addition is also made of the magnitude of the negative going component with respect to the reference value VD out of the peak values of the feedback voltages in the negative voltage addition circuit, whereby the output VB is provided. The above described outputs VAA and VB are added to each other in the positive/negative voltage addition circuit, whereby the output VE is provided. The output voltages of the hall-effect devices (.alpha., .beta. and .gamma.) are controlled such that the magnitude of the output VE may be consistent with the magnitude of the control signal (VF) in a difference control circuit (209 and 201). Accordingly, it was confirmed that a torque ripple of the motor is drastically mitigated.

Control apparatus of transistor motor

Growing community of inventors

Nakatsugawa, Japan

Toshio Tatsutani