Patents by Inventor Norton W. Risdal

Norton W. Risdal 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).

  • Sampler for flowing pressurized dry material
    Patent number: 4433587
    Abstract: A sampler for dry material flowing under pressure in a flow duct including a tubular housing, mounting an air cylinder, the piston rod of which connects to a sample tube which is extendible from the housing and into the flow line, the sample tube having a plug forming an obstruction in its rear portion, the forward portion of the sample tube having a material receiving slot in one side facing upstream in the flow duct, and a bleed port on the downstream side of the sample tube adjacent the receiving slot, the sample tube having a discharge port adjacent the front face of the plug in the sample tube and aligned with an outlet opening in the tubular housing and with an outlet spout to which a sample collecting container may be attached, and a seal in the tubular housing spanning entirely across the receiving port and discharge port and the space therebetween on the sample tube and confronting the fluid pressure in the sample tube as the sample tube is withdrawn, until the discharge port opens to the outlet open
    Type: Grant
    Filed: January 17, 1983
    Date of Patent: February 28, 1984
    Assignee: Gustafson, Inc.
    Inventor: Norton W. Risdal