Richard B Harper

US Patent:

7282873, Oct 16, 2007

Filed:

Nov 16, 2004

Appl. No.:

10/989866

Inventors:

Bulent Abali - Tenafly NJ, US
D. Scott Guthridge - New York NY, US
Richard E. Harper - Chapel Hill NC, US
Peter A. Manson - Cary NC, US

Assignee:

Lenovo (Singapore) Pte. Ltd. - Singapore

International Classification:

H02P 5/00

US Classification:

318 41, 318 49, 318268, 417 2, 417 42

Abstract:

A multi-fan apparatus and method incorporates mutual active cancellation of fan noise and/or vibrations. The multi-fan apparatus includes two or more fans circuits, each comprising a fan, a fan speed controller and a separate tachometer, and a fan phase controller. The phase controller is connected to at least one fan speed controller and to each tachometer. Each fan's speed is independently and dynamically maintained at the same set speed by the fan speed controllers using an independent control loops. A noise and/or vibration cancellation phase difference between fans is determined in order to achieve destructive interference of pressure waves and, thus, noise and/or vibration reduction, in pre-determined region of a system incorporating the multi-fan apparatus. The phase controller establishes and maintains this cancellation phase difference between the fans based upon feedback from the tachometers.

US Patent:

8013259, Sep 6, 2011

Filed:

Jun 11, 2008

Appl. No.:

12/137028

Inventors:

Raymond M. Hill - Plainfield IL, US
Richard L. Harper - Frankfort IL, US
Robert T. Fitzpatrick - New Lenox IL, US

Assignee:

Panduit Corp. - Tinley Park IL

International Classification:

H02G 3/04

US Classification:

174481, 174 681, 174 95, 174 70 R

Abstract:

The present invention is directed toward a divider clip that holds a divider wall in a multi-channel raceway. The divider clip includes a base and sidewalls extending from ends of the base. The divider clip also includes removable clip fingers that extend from the base. One of the removable clip fingers is located at the center of the base while a second removable clip finger is located closer to one of the sidewalls. One of the clip fingers is removed from the divider clip to enable the remaining clip finger to hold to divider wall to separate the raceway into either a 50/50 channel split, a 60/40 channel split or a 40/60 channel split.