Paul C Stevens

US Patent:

6607349, Aug 19, 2003

Filed:

Nov 14, 2001

Appl. No.:

09/992847

Inventors:

Tom G. Mulera - Mesa AZ
Dave K Faymon - Phoenix AZ
Kevin A. Jones - Phoenix AZ
Paul M. Stevens - Oro Valley AZ

Assignee:

Honeywell International, Inc. - Morristown NJ

International Classification:

F01D 2106

US Classification:

415 1, 415 9, 415 14, 415 16, 415118

Abstract:

The broken shaft detection system and method uses a detector assembly mounted downstream of a power turbine wheel of a gas turbine engine to detect rearward axial motion of the wheel and thereby a broken shaft event. The detector assembly has a plunger positioned to be axially displaced against a link connected in an electrical circuit. The link may be broken when the plunger is displaced thereby creating an open circuit that may be detected by a detection and test element. The breaking may be communicated to an overspeed circuit that controls a shut off switch that interrupts fuel flow to the engine. The link may be connected to the detection and test element by two pairs of parallels wires to facilitate monitoring of circuit function and to detect failures that are not broken shaft event failures.

US Patent:

6798192, Sep 28, 2004

Filed:

Jun 11, 2002

Appl. No.:

10/170525

Inventors:

David K. Faymon - Phoenix AZ
Tom G. Mulera - Mesa AZ
Paul M. Stevens - Oro Valley AZ
Mansoor Shah - Tucson AZ

Assignee:

Honeywell International, Inc. - Morristown NJ

International Classification:

G01P 344

US Classification:

324166, 324173, 32420725

Abstract:

An electronic circuit measures a pulse frequency and/or a pulse period of pulses in a sensor signal originating in a sensor coil, the pulses being zero crossing pulses. The circuit includes a filter stage having an input connected to the sensor coil, the filter stage being for removing electrical noise from the sensor signal to provide a filtered sensor signal. The circuit also has a signal strength sensing circuit connected to receive at least one of the sensor signal and the filtered sensor signal, the signal strength sensing circuit producing a variable threshold signal, which is a substantially monotonically non-decreasing function of a strength of the sensor signal. A variable threshold zero crossing detector is connected to receive the filtered sensor signal and the variable threshold signal. The variable threshold zero crossing detector has an upper threshold to test for zero crossing in a positive direction and a lower threshold to test for zero crossing in a negative direction. One or both of the thresholds is dependent on the variable threshold signal.