抄録
VGR (Variable Gear Ratio) rack & pinion is a machine element that the rotation angle of the pinion changes the movement distance of the rack. It is used the power steering device for the car. As a result, the conflicting performance it is the stability when going straight and the steer when turning can be improved at the same time. When the motion of this mechanism was evaluated, the error was caused in the theory value and measurements in the movement distance of rack to rotation angle of pinion. Then, the cause of the error is examined by the measurement tooth surface is compared with the theory tooth surface. There, it is shown that this error is influenced by the lead error in right tooth surface from relation of lead error and contact line.
