Patents Assigned to Snap-on Equipment GmbH
  • Patent number: 7752903
    Abstract: The present invention relates to a roller brake testing dynamometer (P) for vehicles whose braking forces are to be ascertained, wherein there is provided at least one roller (L) which is driven by way of a drive (A) in order in turn to drive a vehicle tire (R) bearing against the roller (L), and wherein the dynamometer (P) has at least one contact-less sensor unit (S) for detecting the position of the tire (R) relative to the at least one roller (L).
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: July 13, 2010
    Assignee: Snap-On Equipment GmbH
    Inventor: Erich Seibl
  • Patent number: 7584654
    Abstract: The present invention relates to a roller brake testing dynamometer (P) for vehicles whose braking forces are to be ascertained, wherein there is provided at least one roller (L) which is driven by way of a drive (A) in order in turn to drive a vehicle tire (R) bearing against the roller (L), wherein there is provided at least one braking force sensor (S) for ascertaining a braking force exerted on the roller (L) by the tire (R), and wherein there is provided an evaluation and control unit (E) to which the signals of the braking force sensor (S) can be fed. Furthermore, it is provided that the evaluation and control unit (E) is adapted on the basis of the signals from the braking force sensor (S) to ascertain the transition from static friction to sliding friction between the tire (R) and the roller (L) independently of the speed of rotation of the roller.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: September 8, 2009
    Assignee: Snap-On Equipment GmbH
    Inventor: Erich Seibl
  • 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
  • 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: 6729032
    Abstract: The invention concerns an apparatus and a method for the chassis measurement of vehicles such as motor vehicles, wherein the apparatus includes a vehicle lift platform with which a chassis to be measured can be reversibly lifted and an axle measurement lifting device with which an axle measuring unit can be reversibly lifted. The axle measurement lifting device has at least two lifting stages which are actuable reversibly independently of each other.
    Type: Grant
    Filed: May 8, 2001
    Date of Patent: May 4, 2004
    Assignee: Snap-On Equipment GmbH
    Inventor: Tebaldo Granata
  • 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: 6622551
    Abstract: An apparatus for balancing vehicle wheels, comprising a machine frame 10, a main shaft 12 which is mounted rotatably in the machine frame 10 and on which a vehicle wheel to be balanced can be clamped, and a guard hood 20 which at least partially engages over the vehicle wheel to be balanced and which has a stationary guard hood element 22 and a movable guard hood element 24 which is movable reversibly from an operative position into an inoperative position, wherein an operating and display unit 40 is arranged in the region of the end 22a of the stationary guard hood element 22, which faces into the operative position of the movable guard hood element 24.
    Type: Grant
    Filed: February 16, 2001
    Date of Patent: September 23, 2003
    Assignee: Snap-on Equipment GmbH
    Inventors: Klaus Rühl, Andreas Ries, Eberhard Klett, Dieter Fornoff
  • 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