Edward K Cheng

US Patent:

6701761, Mar 9, 2004

Filed:

Feb 11, 2003

Appl. No.:

10/365597

Inventors:

Roger N. H. Chang - Taipei, TW
Edward J. Cheng - Northbrook IL

Assignee:

Bauer Products, Inc. - Grand Rapids MI

International Classification:

E05B 2904

US Classification:

70337, 70338, 70340, 70360, 70369, 70421

Abstract:

A lock system is provided for vehicles and the like of the type having at least one closure. A lock housing is mounted adjacent the closure, and includes a lock barrel with an axial tumbler groove, a positioner shoulder adjacent an outer portion of the barrel and a keeper shoulder adjacent an inner portion of the barrel. A lock plug is closely received in the barrel for rotation between locked and unlocked positions, and includes a keyway and outwardly biased, radially shifting tumblers. A control key is inserted into the keyway to retract all of the tumblers except a positioner tumbler that engages the positioner shoulder to locate the lock plug in a first axial position in the barrel. When the control key is removed, an outer keeper tumbler is biased outwardly for abutting contact with the keeper shoulder. A dealer key is inserted into the keyway to retract all of the tumblers except the positioner and outer keeper tumblers to permit rotation of the plug between the locked and unlocked positions. A customer key is inserted into the keyway to retract all of the tumblers except the outer keeper tumbler, and shift the plug axially into a second axial position in the barrel, wherein an inner keeper tumbler is biased outwardly for abutting contact with the keeper shoulder, and the positioner tumbler is shifted into the tumbler groove to prevent rotation of the plug by the dealer key to provide customer security.