Fan performance by increasing effective blade height in a tolerance neutral manner

摘要

The described embodiments relate generally to improving performance characteristics of a low profile fan. More specifically configurations having sloped fan blade edges are disclosed. By applying a gradual slope to each of the fan blades, performance of the fan can be increased without risking contact or rubbing between the fan blades and a fan housing. In some embodiments, the sloped fan blades can be configured to prevent contact when bearings of the fan include a certain amount of tilt play.

主权项

1. A centrifugal fan assembly for cooling a computing device, comprising:
a fan assembly housing, comprising:
a top cover; and a rotor, comprising:
a shaft mechanically coupled to a rotational drive, the rotational drive configured to impart a rotational force on the shaft, causing the shaft to rotate at a rotational velocity, andan impeller centrally attached to the shaft comprising a fan blade at an outside perimeter of the impeller, the fan blade comprising a leading edge, a trailing edge, a top edge disposed between the leading and trailing edge, and a bottom edge disposed between the leading edge and trailing edge, the top edge characterized as having a top slope Stop that prevents contact between the top edge and the top cover, the top slope Stop corresponding to a height of the leading edge being greater than that of the trailing edge, the bottom edge characterized as having a bottom slope Sbottom corresponding to the height of the leading edge being greater than the height of the trailing edge, wherein the shaft is mechanically coupled to the rotational drive by a fluid bearing, and wherein the top slope Stop results in a minimum cover clearance between the top edge and the top cover along at least a portion of the top edge length when the impeller experiences a maximum possible tilt relative to the top cover.