Abstract: A fan motor is provided. The fan motor includes a case having a cylindrical bearing housing, and a base unit fixing the cylindrical bearing housing; a pair of bearings fitted into the cylindrical bearing housing; a stator which has a wound coil and a bottom portion to which a PC board including a motor driving circuit and a lead wire for supplying the motor driving circuit with electrical current is fixed; a shaft supported by the pair of bearings; a rotor which faces the stator and is fixed to the shaft, and which has a magnet; and an impeller which is fixed to an outer peripheral portion of the rotor, and has plural blades. The stator, the PC board and the lead wire are molded by epoxy resin which has hardness of Shore D85 to D95 after curing and a glass transition temperature of 125° C. or higher.

Abstract: A fan motor is provided. The fan motor includes a case having a cylindrical bearing housing, and a base unit fixing the cylindrical bearing housing; a pair of bearings fitted into the cylindrical bearing housing; a stator which has a wound coil and a bottom portion to which a PC board including a motor driving circuit and a lead wire for supplying the motor driving circuit with electrical current is fixed; a shaft supported by the pair of bearings; a rotor which faces the stator and is fixed to the shaft, and which has a magnet; and an impeller which is fixed to an outer peripheral portion of the rotor, and has plural blades. The stator, the PC board and the lead wire are molded by epoxy resin which has hardness of Shore D85 to D95 after curing and a glass transition temperature of 125° C. or higher.

Abstract: An axial fan motor comprising a cylindrical bearing boss having therein a bearing mechanism for supporting a rotational shaft of the axial fan motor and a stator core coupled to the cylindrical bearing boss is disclosed. The bearing boss is, at its one end portion, coupled integrally to an insulator so that said stator core is sandwiched between the insulator and another insulator so as to insulating the stator core. A stator-holding section is defined in a housing of the axial fan motor and the stator-holding section has a cylindrical bearing boss receiving portion whose axis is substantially coincident with the axis of the rotational shaft of the axial fan motor.

Abstract: A burn-out preventive circuit for a commutatorless motor comprises drive windings of two phases, driving power transistors connected in series with the drive windings respectively, a position detecting element detecting the angular position of rotation of a permanent magnet rotor for alternately turning on the driving power transistors, and a protective circuit detecting a counter-electromotive force induced in the drive windings during rotation of the permanent magnet rotor for interrupting energization of the drive windings when the detected counter-electromotive force is lower than a predetermined level or zero.