Patents by Inventor Paulus J. C. Van Leest

Paulus J. C. Van Leest 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).

  • Switched-mode power supply
    Patent number: 5973938
    Abstract: A switched-mode power supply comprises a transformer (2) having a primary winding (4) connected to a first pair of direct voltage terminals (8, 10) via a switching transistor (6) and having a secondary winding (22) which powers a load (24) via a diode (26). The switched-mode power supply further comprises a second switching transistor (34) which, together with the secondary winding (22), the load (24) the diode (26) and a second pair of direct voltage terminals (38, 40) is configured as a forward converter to power the load from a comparatively low direct voltage (12 V d.c.) supply.
    Type: Grant
    Filed: May 4, 1998
    Date of Patent: October 26, 1999
    Assignee: U.S. Philips Corporation
    Inventor: Paulus J. C. Van Leest
  • Motor control arrangement, and shaver comprising such a motor control arrangement
    Patent number: 5617503
    Abstract: A motor control arrangement including a control circuit for controlling the speed of an electric motor (EM), which control circuit comprises a measurement resistor (MR) and a switching transistor (ST) having a control electrode and a main current path coupled in series with the electric motor (EM) and the measurement resistor (MR), a pulse width control stage (PW) coupled to the control electrode of the switching transistor (ST), a motor current measurement stage (MI) for controlling the pulse width control stage (PW) in response to a motor current of the electric motor (EM), and a motor voltage measurement stage (MV) for controlling the pulse width control stage (PW) in response to a motor voltage (EM) of the electric motor (EM).
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: April 1, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Robert J. Fronen, Paulus J. C. Van Leest, Franciscus A. C. M. Schoofs