PROBLEM TO BE SOLVED: To provide an electric traction inspection apparatus rapidly performing inspection by stably self-traveling on an overhead line while avoiding obstacles without hindrance.
SOLUTION: The inspection apparatus 1 inspects two overhead lines M using an eddy current sensor 18 while traveling on the overhead lines M by means of four travel rollers 3 driven by motors 4 and 5. Retaining roller 6 are provided for rolling on the lower surfaces of the overhead lines M during travel. Arms 7 for supporting the retaining rollers 6 are freely rotatably supported against a frame 2 and rotated by an arm driving motor 10 between a retaining position and a retracted position. The arms 7 position the rollers 6 below the overhead lines M at the retaining position and position the rollers besides the frame 2 at the retracted position. Sensors 14, 15 and 16 are used to detect any obstacles on a path of travel, with the arms 7 rotated outwards in accordance with the sensor signals to avoid the obstacles. As the arms 7 advance, the front and rear of the arms are individually brought into retracting movement, and either the front or rear retaining roller 6 holds the overhead line M from below at any times.