Abstract: A motor assembly includes a flexible base mount having an axial tube, a rigid outer mounting shell member inserted into and retained to the axial tube by retaining and retained members disposed therebetween, a stator winding subassembly surrounding the outer mounting shell member and supported by resting on a surrounding ledge of the axial tube, a plug member engaging in a socket cavity of the outer mounting shell member, a flexible inner mounting shell member inserted into the outer mounting shell member, a rotating shaft of a rotor subassembly received in the inner mounting shell member and rotatably born by an antifriction bearing, and an upper positioning ring resting on the bearing. Leakage of lubricant and deformation of the inner mounting shell member can be prevented.

Abstract: A motor assembly includes a flexible base mount having an integrally formed axial tube, support ledges disposed on the axial tube to axially support a stator disposed on the axial tube to be firmly engaged with the stator for further ensuring immobility, a flexible mounting shell member axially insertable into the axial tube and having a receptacle cap at a lower end thereof, retaining and retained members disposed between the mounting shell member and the axial tube to guard relative movement therebetween, and an antifriction bearing disposed in the mounting shell member to bear a revolving shaft of a rotor. All the constituted components can be standardized and modularized. With such simple construction, the motor assembly can be easily assembled.

Abstract: A rotation speed control device for a heat-dissipating fan includes an impedance unit, a regulating unit, and a driving circuit. The impedance unit includes a first resistor having a first end connected to a first node, and a second end connected to a second node, and a second resistor having a third end connected to the second node, and a fourth end. The regulating unit is connected to the impedance unit and is configurable for varying an effective impedance of the impedance unit to adjust magnitude of current flowing through the impedance unit. The driving circuit is connected to the impedance unit and is adapted to control rotation speed of the heat-dissipating fan according to the magnitude of the current flowing through the impedance unit.