Device for testing i.e. measurement of tilting clearance between ball nut and spindle, of ball screw in electro-mechanical power steering apparatus of motor car, has drive motor rotating ball nut and/or spindle during operation of device

摘要

The device has a frame with a retainer (2) for holding a spindle (3), and a holder (7) for a ball nut (8). Displacement sensors (17, 17') or tilt angle sensors measure a relative position of the spindle to the ball nut in a direction of a Z-axis and tilt angle against the Z-axis. Actuators (18, 18') e.g. jackscrew actuators, and pressure- and traction parts (19, 19') produce a bias of the ball nut against the spindle as rotational torque at a rotational axis normal to the direction of the Z-axis. A drive motor (4) rotates the ball nut and/or the spindle during operation of the device. An independent claim is also included for a method for testing a ball screw.