Patents by Inventor Jack P. Chang

Jack P. Chang 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: 4429987
    Abstract: An early roll closure method and apparatus associated with an electrophotographic or xerographic device for fixing a toner image onto a copy sheet by application of heat and pressure. A lower closing force is exerted on the fuser rollers during early roll closure than when fixing an image to a copy sheet. The use of a backup roll made of bare metal facilitates this technique. This early roll closure method also allows the temperature of the heated fuser roll to be reduced along the entire circumference. The early roll closure is only allowed to occur on the first sheet of a copy or fusing run.
    Type: Grant
    Filed: February 16, 1982
    Date of Patent: February 7, 1984
    Assignee: International Business Machines Corporation
    Inventors: Jack P. Chang, Marc L. Steinbrecher
  • Patent number: 4253392
    Abstract: An electrophotographic copier machine with a roll fuser where one of the mating rolls is comprised of a thin outer shell which takes a variable taper so that a concave shape is produced under high humidity conditions and a relatively straight roller is produced under low humidity conditions. Means for changing the support at the roll ends is provided to produce the variable taper. End plugs can be moved axially inward at high humidity to provide support for the end portions of the normally concave roll and can be moved axially outwardly under low humidity such that no support is provided until the roll ends are flattened under the pressure of a mating roll.
    Type: Grant
    Filed: April 9, 1979
    Date of Patent: March 3, 1981
    Assignee: International Business Machines Corporation
    Inventors: Fred Y. Brandon, Jack P. Chang, William D. Clark, Eugene G. Stahlberg