Patents by Inventor Duncan Johnstone

Duncan Johnstone 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).

  • Industrial vacuum loader with dust removal means for bag house filtration system
    Patent number: 4017281
    Abstract: An industrial vacuum loader comprises an enclosed hopper into which particulate matter is drawn through a loading hose. The hopper is connected by a suction hose to the lower intake port of a bag house and the upper outlet port of the bag house is connected by a transformation hose to the suction port of an engine-driven positive displacement rotary blower. The bag house comprises an upper chamber containing filtration bags and a lower dust collection chamber in which dust filtered from dust-laden air passing through the bag house is collected.
    Type: Grant
    Filed: October 2, 1975
    Date of Patent: April 12, 1977
    Inventor: Duncan Johnstone