Patent Number: 6,254,343

Title: Low-noise cooling fan for electronic components and method of making the same

Abstract: An improved cooling fan (12) fan for cooling an electronic component includes a rotor (26) rotatably mounted in a housing (18) and having a plurality of fan blades (28). The housing (18) includes a first end (20), a second end (24), and a passage (24) interconnecting the first end and the second end to define an air flow path (25) therebetween. An entry port (16) is defined by an upstream portion of the housing (18) generally adjacent the housing first end (20), with the entry port (16) having a cross-sectional area greater than a cross-sectional area of the passage (24). The entry port (16) and the passage (24) being separated by a transition zone (30), with the entry port (16) and the transition zone (30) cooperating to define an abrupt step (36). The abrupt step (36) is adapted to at least partially affect the flow of air flowing along the flow path (25), thereby reducing the ambient noise level of the fan.

Inventors: Schmidt; Detlef W. (Schaumburg, IL), Morris; Garron K. (Niskayuna, NY)

Assignee: Motorola, Inc.

International Classification: F01D 5/14 (20060101); F04D 29/66 (20060101); F04D 29/40 (20060101); F04D 29/54 (20060101); H05K 7/20 (20060101); F01D 001/00 ()

Expiration Date: 07/03/2018