Abstract: A fence control feature described herein may be used with a combination lock. The fence control feature includes a trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point. A bracket is preferably vertically elevated above the overcenter arm. An apron is preferably formed on the overcenter arm. The apron may be for preventing a nose of a pivotable fence lever arm from catching on the trigger plate. The apron may be a half-moon-shaped apron.

Abstract: A resistant mechanical combination lock and improvements thereto are described herein to include one or more of the following features: an improved combination change/set feature that includes a tumbler interlocking lever with digitated micro-fingers suitable for interdigitating with digitated micro-fingers on the peripheral edge of a combination tumbler ring, the tumbler interlocking lever and the combination tumbler ring sandwiched between a pair of outer gate rings to form a tumbler wheel assembly; a key stabilization feature in which an internal boss and a pivot recess together help stabilize the change key when changing the combination of a lock to help prevent “lock out”; an improved duress feature that includes a duress tumbler wheel assembly (that includes a duress lever) and an interchangeable microswitch; and/or a fence control feature that preferably includes an overcenter spring and trigger plate for controlling fence contact with the drive cam.

Abstract: A resistant mechanical combination lock and improvements thereto are described herein to include one or more of the following features: an improved combination change/set feature that includes a tumbler interlocking lever with digitated micro-fingers suitable for interdigitating with digitated micro-fingers on the peripheral edge of a combination tumbler ring, the tumbler interlocking lever and the combination tumbler ring sandwiched between a pair of outer gate rings to form a tumbler wheel assembly; a key stabilization feature in which an internal boss and a pivot recess together help stabilize the change key when changing the combination of a lock to help prevent “lock out”; an improved duress feature that includes a duress tumbler wheel assembly (that includes a duress lever) and an interchangeable microswitch; and/or a fence control feature that preferably includes an overcenter spring and trigger plate for controlling fence contact with the drive cam.