Patents by Inventor Sing Kwok Leung

Sing Kwok Leung 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).

  • Vacuum cleaners
    Patent number: 6260235
    Abstract: A vacuum cleaner has a central passage formed by the inside of a casing. The vacuum cleaner is conventional except that two electrically driven fans are provided. The fans are driven respectively by a DC motor 16 and an AC motor. The motors are normally switched ON and OFF individually at the option of a user.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: July 17, 2001
    Assignee: Hoovine Plastic & Electronic Factory Ltd.
    Inventor: Sing Kwok Leung
  • Vacuum cleaner
    Patent number: D398099
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: September 8, 1998
    Inventor: Sing Kwok Leung