Patent · US Expired

Method and apparatus for controlling a variable speed fan in an image forming device

US7012390B1 · kind B1 · utility

2Cited by
1References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 6, 2004
Grant dateMar 14, 2006
Priority date
Expiry dateJan 10, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G21/206
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An improved variable speed fan controller for use in devices such as laser printers. The controller automatically adjusts its output signal to fans such that a fan quickly settles into an appropriate operating speed, even if the fan has been newly installed into the equipment. The controller can store values in non-volatile memory, if desired, to keep track of recent changes in the fan's operating parameters and corresponding control signal values. The controller is able to control relatively inexpensive fans that don't necessarily operate at a predictable fan rotating speed under repeatable conditions and control signals, by controlling the fan to an initial or predetermined rotating speed; if the fan isn't running within a suitable range of rotational speeds, then determining whether a fine or coarse adjustment should be made to the fan's rotational speed. The controller makes appropriate adjustments until the fan's rotational speed is within acceptable operating tolerances.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.