Patents Assigned to Grundfor A/S
  • Method of stepwise speed control and three-phase squirrel-cage motor
    Patent number: 4035701
    Abstract: A method of stepwise speed control, and three-phase squirrel-cage motor, that comprises main windings connected either in a delta or in a star circuit, the main windings being connected to at least one set of additional windings that are also connected either in delta or in star. The method permits at least five different speeds of rotation without the use of a transformer.
    Type: Grant
    Filed: March 27, 1975
    Date of Patent: July 12, 1977
    Assignee: Grundfor A/S
    Inventor: Axel Jensen