Abstract: A DC brushless vibration motor is disclosed to comprise of a stator, a rotor, a drive circuit and a casing. The stator has an upper magnetic pole piece, a lower magnetic pole piece and a stator field winding. The stator field winding is contained inside a ring-shaped space formed by the upper and lower magnetic pole pieces. The internal rotor has a center of mass offset from the center axis of rotation and comprises a ring magnet and an eccentric weight. The eccentric weight has a structural configuration of a ring body, and the ring magnet is securely fixed to the external peripheral surface of the eccentric weight. The drive circuit has a drive integrated circuit for controlling the rotation of the rotor by receiving an externally-supplied electric power. The casing securely encloses the stator and rotor while maintaining an air gap therebetween for generating mechanical vibration when the rotor is propelled to rotate by the stator.

Abstract: A DC brushless vibration motor is disclosed to comprise of a stator, a rotor, a drive circuit and a casing. The stator has an upper magnetic pole piece, a lower magnetic pole piece and a stator field winding. The stator field winding is contained inside a ring-shaped space formed by the upper and lower magnetic pole pieces. The internal rotor has a center of mass offset from the center axis of rotation and comprises a ring magnet and an eccentric weight. The eccentric weight has a structural configuration of a ring body, and the ring magnet is securely fixed to the external peripheral surface of the eccentric weight. The drive circuit has a drive integrated circuit for controlling the rotation of the rotor by receiving an externally-supplied electric power. The casing securely encloses the stator and rotor while maintaining an air gap therebetween for generating mechanical vibration when the rotor is propelled to rotate by the stator.

Abstract: A positioning device includes an axle tube for engaging with a circuit board and a stator. The circuit board includes control elements and a sensor element thereon. Each pole of the stator includes two pole ends. A gap exists between two adjacent pole ends respectively of two adjacent poles. The gap receives the sensor element or provides a positioning reference for the sensor element.

Abstract: A positioning device includes an axle tube for engaging with a circuit board and a stator. The circuit board includes control elements and a sensor element thereon. Each pole of the stator includes two pole ends. A gap exists between two adjacent pole ends respectively of two adjacent poles. The gap receives the sensor element or provides a positioning reference for the sensor element.

Abstract: A positioning device for a miniature fan includes a coil seat having an axle tube, an upper polar plate assembly, a lower polar plate assembly, and a winding mounted between the upper polar plate assembly and the lower polar plate assembly. A circuit board is mounted to the axle tube and includes a sensor element for activating rotor. The sensor element is located on a line extending from an end edge of the upper polar plate assembly along a direction parallel to a longitudinal axis of the axle tube.

Abstract: A positioning device for a miniature fan includes a coil seat having an axle tube, an upper polar plate assembly, a lower polar plate assembly, and a winding mounted between the upper polar plate assembly and the lower polar plate assembly. A circuit board is mounted to the axle tube and includes a sensor element for activating a rotor. The sensor element is located on a vertical line extending from an end edge of the lower polar plate assembly along a direction parallel to a longitudinal axis of the axle tube.

Abstract: A positioning device for a miniature fan includes a coil seat including a number of annularly spaced poles each having a radially extending stem and a circumferential arcuate section. Each stem has a winding wound therearound, and each arcuate section has a first end edge and a second end edge. A circuit board is securely connected to the coil seat and includes a sensor element mounted thereon. The sensor element is located on a vertical line extending from one of the first end edge and the second end edge of one of the poles.

Abstract: An engagement assembly includes an engaging plate mounted to a holed fin of each of the two outermost opposite rows of fins of a finned plate. Each engaging plate includes at least one first slot defined in a lower portion thereof for releasably engaging with an associated protrusion on a pin seat and a second slot defined in a mediate portion thereof. A press plate is mounted outside each engaging plate and includes an eccentric hole defined therein. A positioning element is extended through the eccentric hole of each press plate, the second slot of the associated engaging plate, and the hole of the associated holed fin. When the press plate is rotated through a pre-determined angle rotated about the positioning element to bear against a lip formed on a top of the associated engaging plate, the engaging plate is moved upwardly such that the first slot of the engaging plate firmly engages with the associated protrusion.