Gerald A Brown

US Patent:

6827551, Dec 7, 2004

Filed:

Feb 1, 2000

Appl. No.:

09/498794

Inventors:

Kirsten P. Duffy - University Heights OH
Gerald V. Brown - Lakewood OH
Ronald L. Bagley - Boerne TX

Assignee:

The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Washington DC

International Classification:

F03B 1104

US Classification:

415119, 416145, 416500

Abstract:

A self-tuning impact damper is disclosed that absorbs and dissipates vibration energy in the blades of rotors in compressors and/or turbines thereby dramatically extending their service life and operational readiness. The self-tuning impact damper uses the rotor speed to tune the resonant frequency of a rattling mass to an engine order excitation frequency. The rattling mass dissipates energy through collisions between the rattling mass and the walls of a cavity of the self-tuning impact damper, as well as through friction between the rattling mass and the base of the cavity. In one embodiment, the self-tuning impact damper has a ball-in-trough configuration with tire ball serving as the rattling mass.

US Patent:

43923569, Jul 12, 1983

Filed:

Feb 19, 1981

Appl. No.:

6/235868

Inventors:

Gerald V. Brown - Lakewood OH

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

F25B 2102

US Classification:

62 3

Abstract:

The method of the invention employs ferromagnetic or ferrimagnetic elements, preferably of rare-earth based material, for example gadolinium, and preferably employs a regenerator. The steps of the method comprise controlling the temperature and applied magnetic field of the element to cause the state of the element as represented on a temperature-magnetic entropy diagram repeatedly to traverse a loop. The loop may have a first portion of concurrent substantially isothermal or constant temperature and increasing applied magnetic field, a second portion of lowering temperature and constant applied magnetic field, a third portion of isothermal and decreasing applied magnetic field, and a fourth portion of increasing temperature and constant applied magnetic field. Other loops may be four-sided, with, for example, two isotherms and two adiabats (constant entropy portions). Preferably, a regenerator may be employed to enhance desired cooling or heating effects, with varied magnetic fields or varying temperatures including three-sided figures traversed by the representative point.

US Patent:

40690288, Jan 17, 1978

Filed:

Nov 30, 1976

Appl. No.:

5/746580

Inventors:

Gerald V. Brown - Lakewood OH

Assignee:

The United States of America as represented by the United States
National Aeronautics and Space Administration - Washington DC

International Classification:

F25B 2102

US Classification:

62 3

Abstract:

The method of the invention employs ferromagnetic or ferrimagnetic elements, preferably of rare-earth based material, for example, gadolinium, and preferably employs a regenerator. The steps of the method comprise controlling the temperature and applied magnetic field of the element to cause the state of the element as represented on a temperature-magnetic entropy diagram repeatedly to traverse a loop. The loop may have a first portion of concurrent substantially isothermal or constant temperature and increasing applied magnetic field, a second portion of lowering temperature and constant applied magnetic field, a third portion of isothermal and decreasing applied magnetic field, and a fourth portion of increasing temperature and constant applied magnetic field. Other loops may be four-sided, with, for example, two isotherms and two adiabats (constant entropy portions). Preferably, a regenerator may be employed to enhance desired cooling or heating effects, with varied magnetic fields or varying temperatures including three-sided figures traversed by the representative point.