Patents by Inventor Filinto Vaz Martins

Filinto Vaz Martins 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).

  • Tape recorder
    Patent number: 4015177
    Abstract: A tape recorder has two tape spools independently driven by two reversible electric motors. The tape passing from one spool to the other drives a tachometer wheel which provides a tape speed signal. This signal is compared with a reference value by a differential amplifier which provides control signals for differentially controlling the speeds of the motors to maintain the tape at a constant speed.
    Type: Grant
    Filed: February 15, 1974
    Date of Patent: March 29, 1977
    Inventor: Filinto Vaz Martins
  • Impedance responsive touch actuated circuit
    Patent number: 3944843
    Abstract: A relay switch for controlling an electronic circuit adapted to adopt two states includes first and second conducting parts spaced apart from one another by an insulating material in a configuration whereby the first and second parts can be connected by a resistance formed by the skin of a user's finger, such connection being effective to control the state of the circuit.
    Type: Grant
    Filed: January 11, 1974
    Date of Patent: March 16, 1976
    Inventor: Filinto Vaz Martins