Back to results
US 3,945,769 AGranted
Self-oscillating fan
OwnerJeffrey P. Sandersoninventor
Life of this patent
Estimating the term…
Abstract
A fan having a single degree of freedom to torsionally oscillate in a horizontal plane which in one version oscillates about a fixed vertical axis, self-excited by an aerodynamic couple created by feathering vertically disposed vanes which are symmetrically located adjacent the tips of the fan blades on the air inflow side thereof, and in another version which oscillates about a pendulous axis, self-excited by precession of the rotating fan and motor armature as a pendulous gyro.
Claims2
A self-exciting oscillating fan comprising:
- a. a stand;
- b. a torsionally elastic means suspended from the stand and having its elastic axis lying on the vertical;
- c. a first polar moment of inertia means including a fan housing and a motor fixedly mounted therein and having an armature connected to said fan, the housing being suspended from the said torsionally elastic means and having an axis of polar moment of inertia coincident with the axis of said torsionally elastic means;
- d. a second polar moment of inertia means comprising said fan, the motor armature and a shaft extending therebetween, said second moment of inertia means having its axis of polar moment of inertia lying in a horizontal plane and intersecting the polar axis of said first polar moment of inertia coincident with the axis of rotation of said fan, motor armature and shaft;
- and
- e. an aerodynamic means for self-exciting said first polar moment of inertia means in oscillation in a horizontal plane about said vertical elastic axis;
- f. said aerodynamic means comprising feathering vanes pivotally mounted in said housing for rotation about axes substantially parallel to the axis of said torsionally elastic means and extending along each side of the fan adjacent the tips of the blades thereof;
- and
- g. means for feathering said vanes.
6 more elements
Dependencies are inferred from the claim text.