Patents by Inventor James G. Dempsey

James G. Dempsey 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: 7971830
    Abstract: A system and method for the initial deployment of a space elevator using a tether, doubly spooled from each end, an inertial mass, beacon satellite and positional thrusters, whereby tether is de-spooled from geosynchronous Earth orbit altitude, using gravity and centripetal force gradient, and timed such that when the tethers fully de-spool or near the point of being fully de-spooled, are released and the free ends, one left to fall inwards to Earth anchor point, and the other left to fall outwards to tether end ballast support point, result in an Earth anchored self supporting tension structure.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: July 5, 2011
    Inventor: James G. Dempsey
  • Publication number: 20100051750
    Abstract: A system and method for the initial deployment of a space elevator using a tether, doubly spooled from each end, an inertial mass, beacon satellite and positional thrusters, whereby tether is de-spooled from geosynchronous Earth orbit altitude, using gravity and centripetal force gradient, and timed such that when the tethers fully de-spool or near the point of being fully de-spooled, are released and the free ends, one left to fall inwards to Earth anchor point, and the other left to fall outwards to tether end ballast support point, result in an Earth anchored self supporting tension structure.
    Type: Application
    Filed: May 1, 2008
    Publication date: March 4, 2010
    Inventor: James G. Dempsey
  • Publication number: 20080228784
    Abstract: A Lock Free and Wait Free method of the appearance of an atomic double word compare and swap (DCAS) operation on a pointer and ABA avoidance sequence number pair of words while using atomic single word compare and swap (CAS) instructions. To perform this function an area of memory is used by this invention and described as a protected pointer. The protected pointer consists of three words, comprising of: a) a pointer to a memory location, such as a node in linked list, together with b) an ABA avoidance sequence number, and combined together with a third word containing c) a specially crafted hash code derived from the pointer and the ABA avoidance sequence number. The three words together are referred to as a three word protected pointer and are used by this invention for implementing a Lock-Free and Wait-Free method of simulating DCAS using three CAS instructions.
    Type: Application
    Filed: March 12, 2007
    Publication date: September 18, 2008
    Inventor: James G. Dempsey
  • Patent number: 6981674
    Abstract: A system and method for a Space Elevator using a transport tether shaped into double catenary with one catenary below synchronous orbit altitude and the second catenary above synchronous orbit altitude and while also forming a harmonic oscillator using a combination of gravitational and centripetal forces with the zero crossing of the harmonic oscillator at an altitude of approximately one half synchronous orbit altitude of attached elevator.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: January 3, 2006
    Inventor: James G. Dempsey
  • Patent number: 3956137
    Abstract: A sewage septic tank is described having a diversion system for diverting effluent from the tank from one drain field to another. A "Y" is provided on the outlet pipe of the tank to enable the effluent from such tank to be directed to either one of two drain fields. A gate valve is provided at the end of each arm of the Y to allow flow within the drain field associated therewith to be controlled. Thus, the effluent from the septic tank can be periodically diverted from one drain field to another so that such fields are allowed to alternately dry out. The position of the actuator for each of the valves provides a simple visual indication of the state of the valve at any given time.
    Type: Grant
    Filed: December 6, 1973
    Date of Patent: May 11, 1976
    Assignee: Langley Hill Quarry
    Inventor: James G. Dempsey