Patents by Inventor Merrill A. Dana

Merrill A. Dana has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5168734
    Abstract: A small re-combinate lock for equipment and furniture such as desks and cabinets. The lock is comprised of a generally cylindrical shell and a removable plug rotatably mounted inside of the shell. The plug has a core and a plurality of multi-piece tumblers slideably mounted in the core. Each tumbler is an assembly comprised of a wafer holder and a combining wafer removably mounted at an end portion of the wafer holder. A wafer support ring is mounted on the core adjacent to one side of each tumbler and a rotatable wafer carrier is mounted on the core adjacent to the opposite side of the tumbler. The wafer support ring is keyed to the core and the wafer carrier is rotatable on the core. In each wafer carrier there are a plurality of coded wafers which can be exchanged with the combinating wafer of an adjacent tumbler. To re-combinate the lock, the plug is first removed from the shell with a master key.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: December 8, 1992
    Assignee: RAD Lock, Inc.
    Inventors: Robert A. Duval, Merrill A. Dana
  • Patent number: 4993784
    Abstract: A locking device including a plurality of small, discrete elements and means for confining the elements in a string. Further included are primary and secondary biasing means at opposite ends of the string for biasing the elements into a contiguous series with each adjacent pair meeting at a junction. The locking device also has a plurality of actuator means. Each of the actuator means in an unlocked state is poised adjacent a junction, and is movable from the unlocked state to a locked state in which it is interjected into its adjacent junction for shifting the remainder of the elements against the force of the biasing means to misalign all of the remaining junctions with respect to their associated actuators and prevent the remaining actuators from moving to the locked state. The biasing means returns all the elements to the contiguous series when the actuator means in the locked state is returned to the unlocked state.
    Type: Grant
    Filed: December 7, 1988
    Date of Patent: February 19, 1991
    Assignee: Engineered Security Products Corporation
    Inventors: Merrill A. Dana, August M. Boucher, Wayne Crepso
  • Patent number: 4910982
    Abstract: A self-assembling locking device including a shell unit with a longitudinal bore, a retaining rim at the front end, and a mounting hole at the rear end. The shell unit further includes means for securing it in a panel aperture which is larger than the shell unit and smaller than the rim. Also included is a plug unit for assembly into the longitudinal bore through the mounting hole. The locking device further includes retaining means for interlocking the plug and shell units and preventing withdrawal of the plug unit form the shell unit through the mounting hole. There is also included means for rotating the plug unit between first and second operative positions.
    Type: Grant
    Filed: October 14, 1988
    Date of Patent: March 27, 1990
    Assignee: Engineered Security Products Corporation
    Inventor: Merrill A. Dana
  • Patent number: 4647734
    Abstract: A key controlled switching apparatus including a body for mounting in an enclosure, the body comprising a front body portion defining a front cylindrical shell and a rear housing secured thereto. A cylindrical locking plug defines a front keyway and is mounted for rotation between locked and open positions within the shell and a plurality of locking tumblers are retained by the plug and extend into the front keyway. Aligned with the locking plug and rotatable therewith is a switching plug extending into the rear housing and defining a rear keyway axially aligned with the front keyway. A plurality of stationary electrical contacts are retained by the rear housing and a plurality of movable electrical contacts are retained by the rear housing and each movable contact is engageable with a different one of the stationary electrical contacts.
    Type: Grant
    Filed: May 20, 1985
    Date of Patent: March 3, 1987
    Assignee: Hudson Lock, Inc.
    Inventor: Merrill A. Dana