Thomas R Griffith

US Patent:

62413252, Jun 5, 2001

Filed:

Oct 14, 1997

Appl. No.:

8/950130

Inventors:

John J. Gowan - Mountlake Terrace WA
Thomas T. Griffith - Seattle WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

B60T 868

US Classification:

303176

Abstract:

A low-speed antiskid control for a multigain hydraulic valve brake system for an airplane is disclosed. The antiskid control includes low- and high-pressure bias modulation (PBM) high step thresholds. At high speeds the low PBM threshold is used to control a PBM high step firing. At low speeds, the high PBM threshold is used to prevent a PBM high step firing unless a deep skid is occurring. The use of a high threshold at low airplane speeds prevents a low speed control loss due to PBM high step firing reducing brake pressure to below minimum brake contact pressure.

US Patent:

61425850, Nov 7, 2000

Filed:

Oct 14, 1997

Appl. No.:

8/949415

Inventors:

John J. Gowan - Mountlake Terrace WA
Trent D. Miller - Renton WA
Jay S. Kallaher - Renton WA
Thomas T. Griffith - Seattle WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

B60T 886

US Classification:

303126

Abstract:

At low speeds, an antiskid/autobrake control system applies a brake release current to the antiskid valves of the brake system associated with selected wheels of an airplane to prevent brake shudder caused by gear walk. The control system obtains a measured wheelspeed value from each of the selected wheels and calculates a reference wheelspeed based the measured wheelspeed. Tests are made to determine if the reference wheelspeed is below some predetermined magnitude, e. g. , 15 knots, and if the airplane ground speed is below some predetermined magnitude, e. g. , 50 knots. If the tests are passed, the value of a low-speed brake release current to be applied to the antiskid valves of the airplane's brake system is determined. In order to prevent an abrupt change in braking, the low-speed brake release value ramps off as the airplane slows to a stop. Releasing some of the brakes results in the pilot increasing pressure on the remaining brakes, thereby eliminating brake shudder due to gear walk.

Address:

11648 Chesterwood Pl, San Diego, CA 92130

VIN:

WDBUF87X48B321121

Make:

MERCEDES-BENZ

Model:

E-CLASS

Year:

2008

Address:

5511 NE 116 St, Vancouver, WA 98686

VIN:

KNADE123876188299

Make:

KIA

Model:

RIO

Year:

2007