Patents by Inventor Lloyd A. Kwok

Lloyd A. Kwok 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).

  • Method of making dental copings
    Patent number: 4944901
    Abstract: A method for producing dental copings using a vacuum tray permits the making of a large number of copings simultaneously using a single sheet of plastic material. Vacuum is applied to the perforated bottom of a box-like tray partially filled with a die retaining medium such as lead shot. Dies are held in position by being embedded in the lead shot and extending above the lead shot. A frame holds a sheet of heat-softenable plastic material, which is heated from above. The frame is lowered onto the shot-containing tray and the vacuum draws the heat-softened plastic material down over the field of dies, producing copings on all the dies simultaneously.
    Type: Grant
    Filed: April 14, 1988
    Date of Patent: July 31, 1990
    Inventor: Lloyd A. Kwok
  • Snap-in articulator insert for easy release of stone model
    Patent number: D509298
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: September 6, 2005
    Inventor: Lloyd A. Kwok
  • Snap-in articulator insert for easy release of stone model
    Patent number: D512148
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: November 29, 2005
    Inventor: Lloyd A. Kwok
  • Set of dental impression trays
    Patent number: D521150
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: May 16, 2006
    Inventor: Lloyd A. Kwok
  • Posterior impression tray
    Patent number: D294062
    Type: Grant
    Filed: November 21, 1985
    Date of Patent: February 2, 1988
    Inventor: Lloyd A. Kwok
  • Anterior articulator
    Patent number: D295218
    Type: Grant
    Filed: November 21, 1985
    Date of Patent: April 12, 1988
    Inventor: Lloyd A. Kwok
  • Posterior articulator
    Patent number: D295314
    Type: Grant
    Filed: November 21, 1985
    Date of Patent: April 19, 1988
    Inventor: Lloyd A. Kwok
  • Toothpick
    Patent number: D298175
    Type: Grant
    Filed: November 21, 1985
    Date of Patent: October 18, 1988
    Inventor: Lloyd A. Kwok
  • Dental high-volume suction cup evacuator with venting
    Patent number: D659824
    Type: Grant
    Filed: June 15, 2011
    Date of Patent: May 15, 2012
    Inventor: Lloyd A. Kwok