PURPOSE: To simplify the construction of a point switch mechanism by rotatably providing a fixing plate for supporting a plurality of power cables to a divergence portion of trolley wire, and by also providing expansion portions for adjusting the length of power cables in the intermediate portions of the power cables in this divergence portion.

CONSTITUTION: Trolley wire A comprises three power cables 1 laid in parallel and a fixing plate 3 having brackets 2... for supporting the power cables 1. The fixing plate 3 in a divergence portion is provided at its end portion with a rotary portion 4 about which the forward end of the fixing plate is put in rotation. A hanger 14 for fixing power cables 1 is attached to the forward end of the fixing plate 3, and a guide cap 8 is fitted to the end portion of each power cable 1. Expansion portions 5 for adjusting the length of the power cables 1 are interposed between brackets 21, 22. Each expansion portion 5 is so constructed that exposed conducters 15 at the both end portions of each power cable 1 are electrically connected together by means of a retaining spring 25 and a slide metal fixture 24.