Resistant mechanical combination lock and improvements thereto
AssigneeMichael J. Walsh & Associates, Inc.
InventorMichael J Walsh
Life of this patent
Estimating the term…
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.
Claims19
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies rotatably stacked on a hub to form a tumbler stack within a lock case, each of said plurality of tumbler wheel assemblies having a tumbler gate, said drive cam having a drive cam gate for engaging a nose of a pivotable fence lever arm, said pivotable fence lever arm for retracting a slideable lock bolt when a correct combination is dialed, and an excentric trigger pin mounted on an outside face of said drive cam, said fence control feature comprising:
- (a) a trigger plate pivotably mountable at a lock case fulcrum on said lock case;
- (b) said trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (c) an overcenter spring;
- and
- (d) said trigger plate further comprising an apron formed on said overcenter arm, said apron extending under said overcenter spring and over said nose and said drive cam gate;
- wherein said overcenter arm is operatively coupled to said pivotable fence lever arm by said overcenter spring such that said nose is normally biased to a first position raised above said drive cam and drops down toward said drive cam gate in a second position for a transitional arc of less than 35 degrees of rotational arc when resiliently urged by said excentric trigger pin acting on said cam follower arm.
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies within a lock case, said fence control feature comprising:
- (a) a trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (b) a bracket vertically elevated above said overcenter arm;
- (c) an apron formed on said overcenter arm;
- and
- (d) said apron formed on said overcenter arm being a half-moon-shaped apron formed on said overcenter arm.
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies within a lock case, said fence control feature comprising:
- (a) a trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (b) a bracket vertically elevated above said overcenter arm;
- and
- (c) a half-moon-shaped apron formed on said overcenter arm;
- wherein said half-moon-shaped apron prevents a nose of a pivotable fence lever arm from catching on said trigger plate.
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies rotatably stacked on a hub to form a tumbler stack within a lock case, each of said plurality of tumbler wheel assemblies having a tumbler gate, said drive cam having a drive cam gate for engaging a nose of a pivotable fence lever arm, said pivotable fence lever arm for retracting a slideable lock bolt when a correct combination is dialed, and an excentric trigger pin mounted on an outside face of said drive cam, said fence control feature comprising:
- (a) a trigger plate pivotably mountable at a lock case fulcrum on said lock case;
- (b) said trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (c) an overcenter spring;
- and
- (d) said trigger plate further comprising a half-moon-shaped apron formed on said overcenter arm;
- wherein said overcenter arm is operatively coupled to said pivotable fence lever arm by said overcenter spring such that said nose is normally biased to a first position raised above said drive cam and drops down toward said drive cam gate in a second position for a transitional arc of less than 35 degrees of rotational arc when resiliently urged by said excentric trigger pin acting on said cam follower arm.
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies within a lock case, said fence control feature comprising:
- (a) a trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (b) a bracket vertically elevated above said overcenter arm;
- (c) an apron formed on said overcenter arm;
- and
- (d) said apron extending under said overcenter spring and over a nose of a pivotable fence lever arm and a drive cam gate.
A fence control feature for use with a combination lock, said combination lock having a combination dial operatively linked to a drive cam and a plurality of tumbler wheel assemblies within a lock case, said fence control feature comprising:
- (a) a trigger plate having an overcenter arm, a stop arm, and a cam follower arm disposed around a common pivot point;
- (b) a bracket vertically elevated above said overcenter arm;
- (c) an apron formed on said overcenter arm;
- and
- (d) said apron extending under said overcenter spring and over a nose of a pivotable fence lever arm and a drive cam gate;
- wherein said apron prevents a nose of a pivotable fence lever arm from catching on said trigger plate.
Dependencies are inferred from the claim text.