Patents Assigned to De Visu International
  • Rollable chart
    Patent number: 4203234
    Abstract: A rollable chart having a web of flexible material wound about two rollers. An endless band extends around pulleys adjacent each roller for manual manipulation. Two unidirectional driving devices are provided each including an internally toothed surface, a disk axially adjacent the toothed surface formed with an inclined cam groove with which a pin on a sliding pawl cooperates.
    Type: Grant
    Filed: July 7, 1978
    Date of Patent: May 20, 1980
    Assignee: De Visu International
    Inventor: Christian Thenon