Patents by Inventor Thomas G. Duff

Thomas G. Duff 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).

  • Stepless ladder assembly and methods of utilizing same
    Patent number: 9682849
    Abstract: A stepless ladder is provided that may comprise a frame adapted to support the weight of a user, a track attached to a portion of the frame, an escalating member attached to the track, the escalating member for supporting the weight of the user, and an escalating assembly adapted to raise and lower the escalating member along the track.
    Type: Grant
    Filed: March 7, 2016
    Date of Patent: June 20, 2017
    Inventor: Thomas G. Duff
  • STEPLESS LADDER ASSEMBLY AND METHODS OF UTILIZING SAME
    Publication number: 20160257542
    Abstract: A stepless ladder is provided that may comprise a frame adapted to support the weight of a user, a track attached to a portion of the frame, an escalating member attached to the track, the escalating member for supporting the weight of the user, and an escalating assembly adapted to raise and lower the escalating member along the track.
    Type: Application
    Filed: March 7, 2016
    Publication date: September 8, 2016
    Inventor: Thomas G. Duff
  • Stepless ladder assembly and methods of utilizing same
    Patent number: 9279288
    Abstract: A stepless ladder is provided that may comprise a frame adapted to support the weight of a user, a track attached to a portion of the frame, an escalating member attached to the track, the escalating member for supporting the weight of the user, and an escalating means adapted to raise and lower the escalating member along the track.
    Type: Grant
    Filed: December 18, 2013
    Date of Patent: March 8, 2016
    Inventor: Thomas G. Duff
  • STEPLESS LADDER ASSEMBLY AND METHODS OF UTILIZING SAME
    Publication number: 20140166399
    Abstract: A stepless ladder is provided that may comprise a frame adapted to support the weight of a user, a track attached to a portion of the frame, an escalating member attached to the track, the escalating member for supporting the weight of the user, and an escalating means adapted to raise and lower the escalating member along the track.
    Type: Application
    Filed: December 18, 2013
    Publication date: June 19, 2014
    Inventor: Thomas G. Duff
  • Central processor utilization monitor
    Patent number: 4485440
    Abstract: Data relative to code instruction use of a central processor unit (CPU) is collected by accumulating counts of code instructions to be executed upon termination of a clock interrupt process over a predetermined interval. Information stored on occurrence of a clock interrupt pulse is evaluated to determine if the code instruction is one under evaluation. If the code instruction is one under evaluation, a count in an associated memory location is incremented. Upon termination of the predetermined interval, the data is read out in histogram form. The data in the histogram is relative to the virtual addresses of the code instructions and, therefore, directly useable by a programmer to evaluate the code use of the CPU without the need for costly and time consuming data unmapping.
    Type: Grant
    Filed: February 13, 1984
    Date of Patent: November 27, 1984
    Assignee: AT&T Bell Laboratories
    Inventors: Thomas G. Duff, Chester S. Zaluk