Patents by Inventor Fredericus W. M. Hulman

Fredericus W. M. Hulman 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: 5367242
    Abstract: A system for charging a rechargeable battery of a portable unit in a rack includes a detection circuit which detects the presence of the unit in the rack. The system has circuitry for transferring of energy from a supply circuit of the rack via a charging circuit of the unit to the battery. The transfer circuit is formed by an induction path which comprises a coil of the rack and a coil of the unit. The unit has a transmission circuit which, after placement of the unit in the rack, transmits a message via a wireless path, for example the induction path, to a control circuit of the rack, the control circuit being connected to the supply circuit. If the rack does not receive, or does not satisfactorily receive, a message expected upon placement of the unit in the rack, the control circuit controls the supply circuit so as to make the supply circuit select a higher transfer rate than normal for the purpose of transferring energy to the battery via the induction path.
    Type: Grant
    Filed: September 18, 1992
    Date of Patent: November 22, 1994
    Assignee: Ericsson Radio Systems B.V.
    Inventor: Fredericus W. M. Hulman