Patents by Inventor Vijitha M. Weerasinghe

Vijitha M. Weerasinghe 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: 4803335
    Abstract: A gas shroud comprises a chamber having a beam inlet, a gas inlet and an outlet portion. A shroud having an inner surface and an outer surface is operably associated with the outlet portion and is rotatable relative to the chamber. A drive system is operably connected to the shroud for rotating the shroud. A plurality of fins are positioned about the outer surface of the shroud and are rotatable therewith so that rotation of the shroud causes the environment surrounding the shroud to be expelled radially away therefrom.
    Type: Grant
    Filed: June 2, 1987
    Date of Patent: February 7, 1989
    Assignee: Quantum Laser Corporation
    Inventors: William M. Steen, Vijitha M. Weerasinghe
  • Patent number: 4777341
    Abstract: A beam monitor comprises a mirror for reflecting an incident beam of radiation to a target and for receiving a reflected beam from the target and has a surface on which the beams impinge. Incident and reflected beam channels are orthogonally disposed within the mirror. Each of the channels has an opening disposed in the surface for admitting the associated beam thereto. First and second detectors are operably associated with the mirror and each generates a signal indicative of a selected characteristic of the beam illuminating the associated channel. A controller compares the generated signals and thereby monitors at least one selected characteristic of the target or of the beam.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: October 11, 1988
    Assignee: Quantum Laser Corporation
    Inventors: William M. Steen, Vijitha M. Weerasinghe
  • Patent number: 4726715
    Abstract: A screw powder feeder has a rotary screw (12) disposed at the base of a hopper (10). The screw (12) comprises a twist drill bit. Powder is discharged into a chamber (18) and picked-up by a flow of gas. The pressure in chamber (18) is varied relative to the pressure in hopper (10) to control the feed rate for a given screw speed. Ultra-low feed rates are made possible by feeding gas into the hopper (10) through the screw (12) and controlling the relative gas pressures such that the pressure in the chamber (18) exceeds the pressure in hopper (10).
    Type: Grant
    Filed: June 9, 1986
    Date of Patent: February 23, 1988
    Assignee: Quantum Laser Corporation
    Inventors: William M. Steen, Vijitha M. Weerasinghe
  • Patent number: 4704030
    Abstract: A predetermined characteristic of a laser beam is detected by disposing a reflector (11) in the path of the beam and coupling an electromechanical transducer (12) to the reflector to detect a mechanical response of the reflector to the incident beam.
    Type: Grant
    Filed: May 15, 1985
    Date of Patent: November 3, 1987
    Assignee: Quantum Laser Corporation
    Inventors: William M. Steen, Vijitha M. Weerasinghe