Mitsubishi Denki Kabushiki Kaisha

Ippei Hagiwara

Kazuhiro Yasumoto

Naoyuki Hara

Tatsuo Yamasaki

Ryohei Uchida

Toshio Tatsutani

Toshio Idei

Etsuo Tamura

In an axial-flow fan, a motor support, a frame having a cylindrical inner surface, a boss fixed to the drive shaft and having a cylindrical outer surface, and blades radially extending from the cylindrical outer surface of the boss is provided legs for connecting the frame and motor support, and are also provided with surfaces inclined with respect to the direction of the air stream to reduce resistance to air flow. In another embodiment, the downstream end of the air duct defined by the cylindrical inner surface of the frame is gradually expanded toward the direction in which air is blown out. In a further embodiment, the upstream end of the boss has cut-away portions for enlarging the area of the cross section for air flow.

Axial-flow fan with tapered hub and duct

Miniature electric motor

Disclosed herein is a disc driving device comprising a base having a fixed substrate and a cylindrical retaining portion integrally formed with the substrate, a rotating shaft rotatably supported to the retaining portion a rotatable hub fixed to the rotating shaft and surrounding the retaining portion, the rotatable hub being provided with an information recording disc at an outer circumference thereof, a driving means for applying a rotational force to the hub, and a reinforcing member provided in the substrate and the retaining portion of the base, the reinforcing member being made of materials having rididity higher than that of the substrate and the retaining portion.

Disc driving device having a reinforced base

A blower comprising a frame formed with an air duct, a shaft support member provided at a substantially central portion of the air duct and mounted through mount legs to the frame, a bearing mounted to the shaft support member, a stator mounted to the shaft support member, a rotating shaft rotatably engaged with the bearing, a rotor fixed to the rotating shaft and having a magnet opposed to an outer circumference of the stator, a printed circuit board electrically connected to the stator, lead wires connected to the printed circuit board, and a connecting portion for connecting the lead wires with the printed circuit board, the connecting portion being located outside of the frame.

Blower

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.

Growing community of inventors

Nakatsugawa, Japan

Ippei Hagiwara