US 4,400,140 A · Compact fan

Abstract

The fan comprises a fan housing surrounding a fan wheel which is coaxial with the fan's drive motor. The drive motor is a permanent-capacitor induction motor with squirrel-cage rotor, the stator of which includes a main winding and an auxiliary winding, the former energized directly from a one-phase A.C. power source, the latter energized through the intermediary of a capacitor, the capacitor serving to produce a second or auxiliary phase of energization for the sake of a rotating stator field. In order that the capacitor not consume valuable space within the fan, especially in the case of a small fan, the capacitor is a wound capacitor of generally annular overall configuration, mounted coaxial with the drive motor radially outward of the drive motor.

Claims12

Dependent claims

A compact fan, comprising an induction drive motor with a stator winding;

a fan wheel driven by the drive motor, the fan wheel having an external diameter;
a fan housing in which the drive motor is mounted;
and a phase-shifting capacitor connected to the stator winding, the capacitor including conductive strips wound up together into an annulus with an internal diameter greater than said external diameter, the annulus being generally coaxial with the drive motor, the capacitor being connecting at corresponding ends of the strips to the stator winding and thereby forming a quasibifilar network connected thereto while being otherwise insulated from the drive motor, said fan housing including a part that surrounds and is generally centered about the fan wheel, said capacitor encircling the fan wheel and being mounted on said part.

Dependencies are inferred from the claim text.

Compact fan

Life of this patent

Compact fan

Life of this patent

Abstract

Claims12