Patents by Inventor Hubert Walz

Hubert Walz 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: 5754019
    Abstract: The invention relates to a method for operating an electric motor in an electrical hand-held tool, such as an electric screwdriver, battery-powered drill or the like, the electric motor being operated during the operating phase (17) at a first rotation speed, which can possibly be preset variably, until a preset limiting torque is reached. On reaching the limiting torque, the electric motor is switched to a further operating phase, which lasts until the electric motor is switched off manually by the user. In this further operating phase, a final torque (20), which is interrupted periodically by torque pauses (19), is exerted by the electric motor. A circuit arrangement for implementation of this method is also described.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: May 19, 1998
    Assignee: Marquardt GmbH
    Inventor: Hubert Walz