Patents by Inventor Karl Rothamel

Karl Rothamel 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: 7377164
    Abstract: In a method and apparatus for balancing a vehicle wheel, the wheel when fixed to a main shaft of a balancing machine, after the implementation of a wheel unbalance measuring run, is stopped at a given rotational angular position for a balancing operation to be carried out on the wheel, by braking of the rotary movement of the wheel. When the wheel is in the stopped condition, a braking moment derived from the unbalance measurement result and applied by a holding brake is caused to act on the wheel so that the wheel is prevented from rotating of its own accord by virtue of its static unbalance.
    Type: Grant
    Filed: April 12, 2005
    Date of Patent: May 27, 2008
    Assignee: Snap-On Equipment GmbH
    Inventors: Karl Rothamel, Burkhard Merg, Gerhard Rossteuscher
  • Patent number: 7055379
    Abstract: In a method and apparatus for checking the uniformity of a pneumatic tire of a vehicle wheel, first and second unbalance measuring operations are performed to determine unbalance vectors of the vehicle wheel, which are ascertained at differing wheel speeds and/or with differing tire pressures and the difference is formed between the unbalance vectors for evaluation of the uniformity of the tire.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: June 6, 2006
    Assignee: Snap-On Equipment GmbH
    Inventor: Karl Rothamel
  • Publication number: 20050241393
    Abstract: In a method and apparatus for balancing a vehicle wheel, the wheel when fixed to a main shaft of a balancing machine, after the implementation of a wheel unbalance measuring run, is stopped at a given rotational angular position for a balancing operation to be carried out on the wheel, by braking of the rotary movement of the wheel. When the wheel is in the stopped condition, a braking moment derived from the unbalance measurement result and applied by a holding brake is caused to act on the wheel so that the wheel is prevented from rotating of its own accord by virtue of its static unbalance.
    Type: Application
    Filed: April 12, 2005
    Publication date: November 3, 2005
    Inventors: Karl Rothamel, Burkhard Merg, Gerhard Rossteuscher
  • Patent number: 6928871
    Abstract: In a method and an apparatus for centeredly clamping a motor vehicle wheel on a shaft of a wheel balancing machine the wheel is first clamped on a centering cone member mounted on the main shaft and then a post-centering operation is effected wherein the wheel is at least partially released, with the wheel being rotated with respect to its initial rotary angle position through about 180°, and then the wheel is clamped on the shaft again.
    Type: Grant
    Filed: May 1, 2003
    Date of Patent: August 16, 2005
    Assignee: Snap-On Equipment GmbH
    Inventor: Karl Rothamel
  • Patent number: 6871543
    Abstract: Apparatus and method for measurement of any unbalance of a motorcycle wheel, having a rotatable main shaft of a wheel balancing machine having an electrical drive, a clamping shaft fixed coaxially with the main shaft and on which the motorcycle wheel is rotatably mounted on its bearings, a driver device which is connected in a non-rotational manner to the main shaft to transmit a torque, produced by the electrical drive, from the main shaft to the motorcycle wheel which is rotatably mounted on the clamping shaft, and a measurement device which, in one measurement run, measures forces from any imbalance of the motorcycle wheel at the measurement rotation speed, where the non-rotational connection between the driver device and the motorcycle wheel can be detached by means of an inertial force, which acts on the driver device and is formed by a torque impulse that is transmitted via the main shall.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: March 29, 2005
    Assignee: Snap-on Equipment GmbH
    Inventor: Karl Rothamel
  • Patent number: 6826958
    Abstract: A method and a device for moving a wheel rotatably mounted on a wheel balancing machine from a first position at which unbalance compensation has been performed, to a second unbalance compensation position for further unbalance compensation. According to the method, the rotor is externally driven, e.g., by hand, to freely running rotation, at which time, a drive motor is energized to generate a torque which acts counter to the direction of rotation of the wheel and to bring the wheel to a stop over a braking distance brought about by the counter torque which corresponds to the angle of rotation which is traveled over up to the unbalance compensation position, whereupon, the motor is de-energized. The apparatus includes a motor drive including an alternating voltage controller having a longitudinal switching device; and a commutation switching device, the switching devices each including two semiconductor switches which are connected in an anti-serial configuration.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: December 7, 2004
    Assignee: Snap-On Equipment GmbH
    Inventors: Karl Rothamel, Lorenz Lenhardt
  • Publication number: 20040118198
    Abstract: In a method and apparatus for checking the uniformity of a pneumatic tire of a vehicle wheel, first and second unbalance measuring operations are performed to determine unbalance vectors of the vehicle wheel, which are ascertained at differing wheel speeds and/or with differing tire pressures and the difference is formed between the unbalance vectors for evaluation of the uniformity of the tire.
    Type: Application
    Filed: December 10, 2003
    Publication date: June 24, 2004
    Applicant: Snap-on Equipment GmbH
    Inventor: Karl Rothamel
  • Patent number: 6752016
    Abstract: A method and an apparatus for balancing a motor vehicle wheel, in which the torque during acceleration to the measurement rotation speed and during braking after carrying out the measurement run is adjusted as a function of the wheel type to be balanced, such that the rotationally fixed connection between the main shaft and the motor vehicle wheel is maintained even when the driving prestressing force between the main shaft and the motor vehicle wheel is reduced.
    Type: Grant
    Filed: January 23, 2003
    Date of Patent: June 22, 2004
    Assignee: Snap-On Equipment GmbH
    Inventor: Karl Rothamel
  • Patent number: 6708563
    Abstract: The invention relates to a device for measuring a rotor imbalance. Said device comprises a main shaft which is rotatably mounted in a machine housing and to which the rotor to be measured is fixed, a single-phase alternating-current motor for driving the main shaft, with a single-phase winding (4) and an auxiliary winding (5) which is offset in phase for driving the main shaft (1) up to measurement speed and a control device (17) that adjusts the current of the motor. Said control device (17) has an assembly (8, 6; 7; 20; 22, 23) which reduces the supply current delivered to the two windings (4, 5) of the motor (3; 21) once the measurement speed has been reached, in such a way that the motor creates a reduced torque which substantially compensates a speed drop produced by friction and drag.
    Type: Grant
    Filed: October 2, 2002
    Date of Patent: March 23, 2004
    Assignee: Snap-On Equipment GmbH
    Inventors: Karl Rothamel, Gottfried Kühn
  • Publication number: 20040035203
    Abstract: In a method and an apparatus for centeredly clamping a motor vehicle wheel on a shaft of a wheel balancing machine the wheel is first clamped on a centering cone member mounted on the main shaft and then a post-centering operation is effected wherein the wheel is at least partially released, with the wheel being rotated with respect to its initial rotary angle position through about 180°, and then the wheel is clamped on the shaft again.
    Type: Application
    Filed: May 1, 2003
    Publication date: February 26, 2004
    Applicant: Snap-on Equipment GmbH
    Inventor: Karl Rothamel
  • Publication number: 20040020290
    Abstract: A wheel guard arrangement in a wheel balancing machine in which the wheel guard member is formed by a flexurally elastic plate which is guided on the machine housing pivotably by a frame. In the open position of the wheel guard arrangement the flexurally elastic plate is flat and positioned vertically and in the closed position it is of an arcuate configuration extending over a wheel to be balanced.
    Type: Application
    Filed: July 3, 2003
    Publication date: February 5, 2004
    Applicant: Snap-on Equipment GmbH
    Inventors: Karl Rothamel, Josef Drechsler
  • Publication number: 20040003661
    Abstract: Apparatus and method for measurement of any unbalance of a motor cycle wheel, having
    Type: Application
    Filed: January 24, 2003
    Publication date: January 8, 2004
    Applicant: Snap-on Equipment GmbH
    Inventor: Karl Rothamel
  • Patent number: 6672158
    Abstract: In a method and an apparatus for balancing a motor vehicle wheel comprising a pneumatic tire and a disk wheel, the wheel is clamped on a measuring spindle and geometrical data of the wheel are sensed and stored. Wheel unbalance is ascertained in at least one measuring run and at least one balancing vector for balancing mass and balancing position is calculated in accordance with a balancing program selected in dependence on the disk wheel type and material, in at least one balancing plane. At least one balancing weight is fixed to the wheel in dependence on the balancing vector. When sensing a rim region of the wheel a sensor detects whether a rim portion extending substantially perpendicularly to the measuring spindle is or is not present in the rim region being sensed and the balancing program is selected in dependence on the signal obtained in the sensing operation with the sensor.
    Type: Grant
    Filed: June 17, 1999
    Date of Patent: January 6, 2004
    Assignee: Hofmann Werkstatt-Technik GmbH
    Inventors: Eickhart Goebel, Bernhard Hoffmann, Karl Rothamel, Walter Hollube
  • Publication number: 20030167840
    Abstract: A method and an apparatus for balancing a motor vehicle wheel, in which the torque during acceleration to the measurement rotation speed and during braking after carrying out the measurement run is adjusted as a function of the wheel type to be balanced, such that the rotationally fixed connection between the main shaft and the motor vehicle wheel is maintained even when the driving prestressing force between the main shaft and the motor vehicle wheel is reduced.
    Type: Application
    Filed: January 23, 2003
    Publication date: September 11, 2003
    Applicant: Snap-on Equipment GmbH
    Inventor: Karl Rothamel
  • Publication number: 20030115957
    Abstract: A method and a device for moving a wheel rotatably mounted on a wheel balancing machine from a first position at which unbalance compensation has been performed, to a second unbalance compensation position for further unbalance compensation. According to the method, the rotor is externally driven, e.g., by hand, to freely running rotation, at which time, a drive motor is energized to generate a torque which acts counter to the direction of rotation of the wheel and to bring the wheel to a stop over a braking distance brought about by the counter torque which corresponds to the angle of rotation which is traveled over up to the unbalance compensation position, whereupon, the motor is de-energized. The apparatus includes a motor drive including an alternating voltage controller having a longitudinal switching device; and a commutation switching device, the switching devices each including two semiconductor switches which are connected in an anti-serial configuration.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 26, 2003
    Applicant: Snap-On Equipment GmbH
    Inventors: Karl Rothamel, Lorenz Lenhardt
  • Publication number: 20030101813
    Abstract: The invention relates to a device for measuring a rotor imbalance. Said device comprises a main shaft which is rotatably mounted in a machine housing and to which the rotor to be measured is fixed, a single-phase alternating-current motor for driving the main shaft, with a single-phase winding (4) and an auxiliary winding (5) which is offset in phase for driving the main shaft (1) up to measurement speed and a control device (17) that adjusts the current of the motor. Said control device (17) has an assembly (8, 6; 7; 20; 22, 23) which reduces the supply current delivered to the two windings (4, 5) of the motor (3; 21) once the measurement speed has been reached, in such a way that the motor creates a reduced torque which substantially compensates a speed drop produced by friction and drag.
    Type: Application
    Filed: October 2, 2002
    Publication date: June 5, 2003
    Inventors: Karl Rothamel, Gottfried Kuhn
  • Patent number: 5959204
    Abstract: A motor vehicle wheel balancing machine holds a motor vehicle wheel by clamping it on a balancing machine measuring spindle. After an operation to measure the unbalance of the the wheel has been preformed, a balancing weight is attached to the wheel using a sensor, and the measuring spindle is stopped with a holding brake which is activated when the sensor is activated.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: September 28, 1999
    Assignee: Hofmann Werkstatt-Technik GmbH
    Inventors: Karl Rothamel, Lorenz Lenhardt
  • Patent number: 5909097
    Abstract: A method of stopping an electric motor-driven balancing machine main shaft after an unbalance measuring run in a specific rotary angle stoppage position corresponding to a desired balancing rotary angle position provides that in the course of retardation of the main shaft, a timer is switched on at a short angular spacing of for example 3.degree. before the main shaft reaches the desired rotary angle stoppage position. The timer predetermines a time interval which is determined from the rotary speed and the rotary angle position of the main shaft at the time of the timer being switched on, with the retardation operation being stopped at the end of that time interval, with the main shaft stationary. The retardation operation can be effected by torque reversal of the motor.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: June 1, 1999
    Assignee: Hofmann Werkstatt-Technik GmbH
    Inventors: Karl Rothamel, Wolfgang Rowe
  • Patent number: 5847277
    Abstract: In a method of rotating a rotary member on a balancing machine into balancing positions in first and second balancing planes, after the unbalance measuring run the rotary member is braked and thus rotated into the balancing position in the first balancing plane, with the braking deceleration being measured. The rotary member is then accelerated to a rotary speed of at most 80 rpm for rotation into the balancing position in the second balancing plane. The rotary member is then braked so that the braking travel resulting from the measured deceleration corresponds to the differential angle still remaining as far as the balancing position in the second balancing plane.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: December 8, 1998
    Assignee: Hofmann Werkstatt-Technik GmbH
    Inventors: Karl Rothamel, Wolfgang Rowe
  • Patent number: 5831152
    Abstract: A wheel balancing machine that includes a lighting device to illuminate the inside of the wheel or rim bowl facing the wheel balancing machine. Illumination preferably occurs in an area above the shaft on which the wheel is mounted and improves the task of correctly positioning and attaching balancing weights.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: November 3, 1998
    Assignee: Hofmann Werkstatt-Technik GmbH
    Inventor: Karl Rothamel