The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 22, 1983
Filed:
Jun. 04, 1981
Robert P Thimot, Marlboro, MA (US);
Hudson Lock, Inc., Hudson, MA (US);
Abstract
A cylinder lock with a shell defining a plug cavity, a plurality of locking shell tumblerways, and a control shell tumblerway. A plug is rotatable within the plug cavity and defines a plurality of locking plug tumblerways alignable with the locking shell tumblerways, a control plug tumblerway alignable with the control shell tumblerway and a keyway for receiving keys. Positioned within each of the locking plug tumblerways is a locking tumbler that is biased into an active position wherein it projects into one of the locking shell tumblerways and movable into an inactive position out of the tumblerway by a proper key in the keyway. The locking tumblers prevent rotation of the plug when in their active positions and allow rotation thereof when in their inactive positions. Retained by the control plug tumblerway is a control tumbler biased in a latched position and movable into a release position by a control key in the keyway. Also defined by the shell is an arcuate groove that receives ends of the control tumbler so as to accommodate rotational movement of the plug while preventing axial movement thereof. After use of a proper key to rotate the plug from a locked position to an open position, an end of the control tumbler can be forced into the control shell tumblerway by a control key in the keyway. Entry of the control tumbler into the control shell tumblerway eliminates axial interference between the control tumbler and the groove.