Patents Assigned to Atlas Copco Controls AB
  • Patent number: 6256893
    Abstract: A power steering system intended for a vehicle having at least one steerable wheel (50) and including an electric servo motor (56), a wheel position related steering control unit (58), and a control unit calibrating device (55,61) for identifying the straight-ahead position of the steerable wheel (50) as the latter is turned within a steering interval defined by a first extreme end position (A) and a second extreme end position (B), wherein the calibrating device comprises a disc shaped element (55) which is rotatable about a central axis (X) in a conjoint relationship with the steerable wheel (50) and provided with a pattern of open and closed portions (64-67,70,71) and a single immobile sensor (61) for producing digital signals in response to its alignment with the open and closed portions (64-67,70,71), wherein a reference point (Y) corresponding to the straight-ahead position of the wheel (50) is defined by the transition from one open portion (64) to one closed portion (65) of the disc shaped element (55
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: July 10, 2001
    Assignee: Atlas Copco Controls AB
    Inventor: Carl Erik Mikael Förborgen
  • Patent number: 6201367
    Abstract: A method for restarting a three-phase synchronous permanent magnet motor in which the rotor is still rotating and in which the motor is connected to a drive unit having a DC-stage with voltage measuring means, a variable voltage and frequency output stage including power switching devices, and a means for determining the current in two of the output phases from the drive unit, wherein the motor with the output stage is momentarily short-circuited, the current magnitudes generated by the motor in the two output phases are measured during the short-circuiting moment, the phase angle generated by the motor during the short-circuiting moment is calculated, the rotor speed is determined, and the drive unit is synchronized with the rotor to enable restarting of the motor.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: March 13, 2001
    Assignee: Atlas Copco Controls AB
    Inventor: Thord Agne Gustaf Nilson
  • Patent number: 6116094
    Abstract: A method for determining the axial load on an elongate member by measuring the differences in time of flight for transversely and longitudinally ultrasonic waves introduced in the elongate member under a zero load condition and at a current temperature and the time of flight for both of these types of waves introduced into the elongate member under the actual load condition, and calculating from these differences in the time of flight the actual load on the elongate member taking into account the influence of any occurring difference in temperature of the elongate member between the zero load condition time of flight measurement and the actual load condition time of flight measurement.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: September 12, 2000
    Assignee: Atlas Copco Controls AB
    Inventor: Tobias Axel Andersson
  • Patent number: 5715141
    Abstract: A control circuit arrangement for an electric motor drive unit includes a circuit board (10), a heat conductive substrate (12) carrying power semiconductors (13), a heat absorbing mounting structure (14) disposed in heat transferring contact with the heat conductive substrate (12), and a clamping structure (20) for clamping the circuit board (10) and the heat conductive substrate (12) to the mounting structure (14). A number of electrically conductive distance or spacer tube elements (22) are disposed between the circuit board (10) and the heat conductive substrate (12) for distributing the clamping force of the clamping structure (20) from the circuit board (10) to the heat conductive substrate (12) while forming electrically conductive leads between the circuit board (10) and the heat conductive substrate (12).
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: February 3, 1998
    Assignee: Atlas Copco Controls AB
    Inventor: Ulf Bengt Ingemar Karlsson
  • Patent number: 5442965
    Abstract: A torque delivering power tool for tightening threaded joints to a desired final pretension level, has a motor (11), a power transmission (12) with a reduction gearing (13) and an output shaft (14). A first torque transducer (19) associated with the power transmission (12) is exposed to torque magnitudes corresponding to delivered torque magnitudes up to the desired final pretension level, and an external second torque transducer (20) is arranged to be exposed to load magnitudes which correspond to torque output magnitudes up to a snug level only.
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: August 22, 1995
    Assignee: Atlas Copco Controls AB
    Inventor: Lars Halen