Zexel Gmbh

Zexel Co., Ltd.

Yoshihide Gunji

Hiroshi Ohsawa

Hideaki Matsuzaki

Shinichi Ohi

Tatsuo Haraguchi

Fuhito Umegaki

Masami Takemasa

Hiroshi Osawa

The present invention offers a simple structure that facilitates the mounting of bearings, that maintains lubricating oil at a sufficient level in the bearing portions and that maintains an optimal distance between a rotor and a case housing for preventing freezing, for preventing reduction of the capacity and for preventing noise. Bearing stoppers provided between the bearings of the brushless motor and the bearing holders, which hold the upper end edge of each bearing, are secured at a projection formed at the internal circumferential surface of each bearing holder. A felt, which comes in contact with the lower portion of each bearing stopper and also comes in contact with the bearing at one side is provided, with holes communicating with the felt formed at the lower surface of the bearing stopper. In addition, the lower limit of the distance h between the lower end of the rotor and the upper end surface of the case housing is set at 1.5 mm. This prevents water from forming a connection between the rotor and the case housing due to capillary action and surface tension. In addition, the upper limit of the distance h is set at or under 8 mm, which represents the critical point for the capacity and the noise. This ensures that the capacity is maintained at a satisfactory level and also prevents noise from increasing. Moreover, a washer group, which comprises at least one each of a resin washer, a rubber washer and a POM (polyoxymethylene) washer is provided between a sensor magnet that is secured to the lower end of the rotating shaft and the lower bearing.

Brushless motor having lubrication system for upper and lower bearings

In an R-C filter for preventing a noise signal from entering a power supply system through its output circuit, a circuit component acting as a resistive element for the filter is connected in series with the output circuit and a capacitive element is connected between one portion of the circuit component and ground to form an R-C type filter. A wiring member, a printed wiring foil, a through-hole member, a semiconductor device or other such circuit component can be used, as the circuit component acting as the resistive element for constituting the R-C type filter.

Power supply filter for preventing noise signal from entering power

When a charging voltage Vs of a charging capacitor C is judged to exceed a voltage Vth1 through a comparator 8 of a charging voltage monitoring circuit 2, a logical output of the comparator 8 becomes 'High' so that a control circuit 3 permits a transistor 4 of a discharging circuit 1 to be conductive, whereby the capacitor C discharges. Through such discharging, the charging voltage Vs decreases. When the voltage Vs is then judged to be less than a voltage Vth2, the logical output of the comparator 8 becomes 'Low' so that the control circuit 3 stops the operation of the discharging circuit 1, whereby a power IC 18 permits the capacitor C to charge again. The charging and the discharging operation of the capacitor C are repeatedly conducted in this manner that.

Overvoltage protection device for capacitor externally connected to

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Kohnan-machi, Japan

Yoshihide Gunji