Patents by Inventor Per C. Andersson

Per C. Andersson 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: 4743824
    Abstract: The invention relates to a method and apparatus for controlling the current (I1, I2) through a stator winding (L1, L2) of a motor (M) which is supplied with energy from a voltage source (V) via a drive circuit (DL1, DL2). The drive circuit is controllable such as to provide at least three different operational states, of which a first normally signifies increasing or maintained magnitude of the current, a second normally signifies shutting down or decreasing the current comparatively slowly and a third operational state normally signifies shutting down or reducing the current comparatively rapidly or at least quicker than in the second operational state. In a method and apparatus in accordance with the invention the desired value time sequence is sensed, and at least the possibility of control so that entry into the third operational state is limited in time in response to the result of sensing the desired value time sequence.
    Type: Grant
    Filed: February 6, 1987
    Date of Patent: May 10, 1988
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventor: Per C. Andersson