Patents by Inventor Ewald Hald

Ewald Hald 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: 6173792
    Abstract: A power-driven screwdriver with a torque-dependent release clutch having two clutch halves is disclosed. The screwdriver comprises additional entrainment elements provided on the clutch halves for bridging the release clutch. To this end, a motor-driven drive gear is mounted to rotate freely on a tool drive shaft and is secured against axial displacement on the housing side while a cam ring can be adjusted axially, together with the tool drive shaft, via an adjusting device. The clutch elements are formed on the respectively facing sides of the drive gear and the cam ring, and the entrainment element are likewise formed, as separate elements, on the respectively facing sides of the drive gear and the cam ring. As a result of the adjusting device axial displacement of the tool drive shaft results either in a rigid through drive, where the release clutch is nonfunctional, or in the torque-dependent release of the release clutch, where the entrainment elements are nonfunctional.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: January 16, 2001
    Assignee: C. & E. Fein GmbH & Co.
    Inventor: Ewald Hald
  • Patent number: 4923047
    Abstract: A motor-driven machine with variable torque setting includes a motor, a planetary gearing driving a work spindle and a rotatably mounted internal gear actuating a motor de-energizer against the action of a spring force when a settable limit torque is exceeded. To achieve a compact design, a torsion spring element extending in the axial direction alongside the planetary gearing is provided for generating the spring force. The torsion spring element carries a swivel element at one end which engages a cam on the internal gear and is held at an opposite end in a support so that the swivel element can swivel out of an initial position against the action of the force of the torsion spring element to de-energize the motor.
    Type: Grant
    Filed: December 15, 1988
    Date of Patent: May 8, 1990
    Assignee: C. & E. Fein GmbH & Co.
    Inventors: Manfred Fink, Wolfgang Schreiber, Manfred Ludwig, Ewald Hald, Guenter Kloss
  • Patent number: 4779687
    Abstract: An electric tool with a source of power that is independent of the line and with a transmission housing or motor housing that is also designed to function as a grip, with another grip merging into one side of it. To position the center of gravity such that the tool will be easier to handle and to allow the operator to continue working when one battery pack goes dead, attachments for battery packs are provided at the end of each grip.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: October 25, 1988
    Assignee: C. & E. Fein GmbH & Co.
    Inventors: Wolfgang Schreiber, Manfred Fink, Ewald Hald, Martin Schultheiss, Manfred Ludwig, Heinrich Henssler
  • Patent number: 4655103
    Abstract: A clutch for power screwdrivers. It has a transmission, an adjustable bit stop, and a drive shaft. It also has a cogwheel with cams on one face and a clutch disk with catches on one face mounted on the drive shaft. The object is a low-noise, wear-resistant clutch. The drive shaft is in one piece. An intermediate disk with catches on one face and cams on the other face is positioned between the cogwheel and the clutch disk. A spring mechanism is positioned between the cogwheel and the intermediate disk.
    Type: Grant
    Filed: January 13, 1986
    Date of Patent: April 7, 1987
    Assignee: C. &. E. Fein GmbH & Co.
    Inventors: Wolfgang Schreiber, Manfred Ludwig, Ewald Hald