Patents by Inventor Robert A. Dunn

Robert A. Dunn 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: 4883200
    Abstract: A thermoplastic melting apparatus comprises a tank pivotally mounted upon bearings within the interior of a housing having a top cover. An electrical or mechanical level indicator device is mounted exteriorly of the tank which is effective to sense pivotal movement of the tank as it is loaded with and/or emptied of thermoplastic material, and to produce a signal which indicates the quantity of thermoplastic material within the tank. The level indicator device is isolated from dynamic forces produced by drive linkages which operate pumps associated with the tank, by positioning the pivot axis of the bearings in the same plane as the force produced by the drive linkage. The lid of the tank is isolated from downward forces applied to the top cover of the housing to prevent the transmittal of forces to the level indicator devices from objects placed on the top cover of the housing or the like.
    Type: Grant
    Filed: September 28, 1988
    Date of Patent: November 28, 1989
    Assignee: Nordson Corporation
    Inventors: Scott R. Miller, Robert A. Dunn
  • Patent number: 4821922
    Abstract: A thermoplastic melting apparatus comprises a tank pivotally mounted upon bearings within the interior of a housing having a top cover. A load cell is mounted beneath the tank opposite the bearings which is effective to sense pivotal movement of the tank as it is loaded with and/or emptied of thermoplastic material, and to produce a signal which indicates the quantity of thermoplastic material within the tank. The load cell is isolated from dynamic forces produced by drive linkages which operate pumps associated with the tank, by positioning the pivot axis of the bearings in the same plane as the force produced by the drive linkage. The lid of the tank is isolated from the top cover of the housing to prevent the transmittal of forces to the tank from objects placed on the top cover of the housing or the like.
    Type: Grant
    Filed: October 29, 1987
    Date of Patent: April 18, 1989
    Assignee: Nordson Corporation
    Inventors: Scott R. Miller, Robert A. Dunn