Patents by Inventor Robert H. Trenkamp

Robert H. Trenkamp 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).

  • Wear compensating optical/magnetic transducer
    Patent number: 4056712
    Abstract: A wear compensating transducer is provided for reading optical and magnetic data from documents comprising a magnetic read head with a group of optical fibers passing through the reluctance gap and with the fiber ends disposed for wiping engagement with documents as they are read. The fiber ends define an optical reading aperture which remains substantially constant as the fiber ends wear with the contact surface of the magnetic head.
    Type: Grant
    Filed: June 9, 1976
    Date of Patent: November 1, 1977
    Assignee: Addressograph Multigraph Corporation
    Inventors: Robert H. Trenkamp, Gerald A. Dissauer
  • Data transducer
    Patent number: 4029944
    Abstract: An optical and magnetic data transducer is provided comprising a magnetic reluctance aperture which is split into two sections with an optical reading aperture disposed generally therebetween. This reduces timing errors between the optical and magnetic output signals indicative of the spacial relation of the optical and magnetic data element boundaries, such errors being due to variations in temperature and skewing.
    Type: Grant
    Filed: April 7, 1976
    Date of Patent: June 14, 1977
    Assignee: Addressograph Multigraph Corporation
    Inventor: Robert H. Trenkamp
  • Security means for transaction terminal system
    Patent number: 4025760
    Abstract: A transaction terminal system is provided including means which prevent the utilization of certain tapped-line data. Security data, such as personal identification numbers or card security codes, is allowed to be distorted by each terminal in a manner which varies from terminal to terminal within the system and is corrected for at the data processor or other appropriate location in a manner specified for the particular terminal sending the data.
    Type: Grant
    Filed: August 14, 1975
    Date of Patent: May 24, 1977
    Assignee: Addressograph Multigraph Corporation
    Inventor: Robert H. Trenkamp