Browse Prior Art Database

CPU Heat Sink Fan with Controlled Fan Blade/Shroud Clearance

IP.com Disclosure Number: IPCOM000130558D
Publication Date: 2005-Oct-26
Document File: 2 page(s) / 128K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a method for manufacturing and controlling the fan-blade-to-shroud clearance for CPU heat sink fans. Benefits include improved aerodynamics and reduced fan noise.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 92% of the total text.

CPU Heat Sink Fan with Controlled Fan Blade/Shroud Clearance

Disclosed is a method for manufacturing and controlling the fan-blade-to-shroud clearance for CPU heat sink fans. Benefits include improved aerodynamics and reduced fan noise.

Background

Currently, standard injection molding is used for tolerancing the fan and shroud components, which creates large clearances between the components. In addition, this solution creates high levels of fan noise, as well as aerodynamic losses.

General Description

Figure 1 illustrates the disclosed method’s design. The CPU heat sink fan (Item 1) has a controlled clearance between the fan blade tips (Item F) and the shroud (Item H), via both the tip and the shroud components. A final dressing operation on the fan blade tips after injection molding of the blades, improves the precision of the overall blade tip (item B) radius, and reduces variance of blade-to-blade tip radii. Controlling the inside shroud diameter improves the precision of the shroud, and tightens the tolerance between the fan blade tips and the shroud.

Given this configuration, the effective air gap (Item G) is reduced. This reduced air gap results in less inefficient airflow around the blade tip, achieved from the air pressure differential between the high and low pressure sides of the blade.

Advantages

The following are advantages of the disclosed method:

 

  • Reduced fan noise. This is accomplished by reducing the amount of aerodynamic vibration from flow around blade ti...