Patents by Inventor Dietrich Holzwarth

Dietrich Holzwarth 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: 7696663
    Abstract: A rotor (2) for a forced-air-cooled electric motor, in particular a universal motor, especially for use with electrical power tools, has a laminated armature (6) incorporating longitudinal slots (8) and with wire windings of a coil (10) protruding from the longitudinal slots (8) on the front face where the windings form coil connecting heads (20, 22). Some or all of the longitudinal slots (8) in the laminated armature (6) contain a rod (28) aligned in the longitudinal direction and protruding axially from one or both front faces (24, 26) of the laminated armature (6), whereby the protruding rod ends thus surround the coil connecting heads (20, 22) on the respective front face to protect the coil connecting heads from abrasive wear.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: April 13, 2010
    Assignee: Metabowerke GmbH
    Inventors: Michael Schmohl, Norbert Falter, Dietrich Holzwarth
  • Publication number: 20090051230
    Abstract: A rotor (2) for a forced-air-cooled electric motor, in particular a universal motor, especially for use with electrical power tools, has a laminated armature (6) incorporating longitudinal slots (8) and with wire windings of a coil (10) protruding from the longitudinal slots (8) on the front face where the windings form coil connecting heads (20, 22). Some or all of the longitudinal slots (8) in the laminated armature (6) contain a rod (28) aligned in the longitudinal direction and protruding axially from one or both front faces (24, 26) of the laminated armature (6), whereby the protruding rod ends thus surround the coil connecting heads (20, 22) on the respective front face to protect the coil connecting heads from abrasive wear.
    Type: Application
    Filed: April 6, 2006
    Publication date: February 26, 2009
    Inventors: Michael Schmohl, Norbert Falter, Dietrich Holzwarth
  • Patent number: 3988656
    Abstract: In a hand-held electric power tool, a combination including an electromotor, and an electric circuit for controlling the speed of the motor, including a pressure switch for controlling the motor speed, a first control potentiometer operatively associated with said pressure switch for adjusting the motor speed from zero up to a predetermined motor operating speed.
    Type: Grant
    Filed: July 3, 1974
    Date of Patent: October 26, 1976
    Assignee: Metabowerke KG Closs, Rauch & Schnitzler
    Inventors: Albrecht Schnizler, Jr., Dietrich Holzwarth