| 摘要 |
<p>PURPOSE:To obtain a crawler-type metal wheel by which a passing wire can be grounded surely without using a grounding roller by a method wherein a grounding plate is installed so as to be movable along the face of a metallic piece and so as to be set to electric continuity with a piece body part and the upper end part of the grounding plate is lifted, up, by a spring, to be higher than the groove bottom face of a wire receiver part. CONSTITUTION:Metal pieces 13 for a crawler-type metal wheel 11 are provided with metal grounding plates 39 on their faces. When a wire 21 is not placed on the crawler- type metal wheel 11, the grounding plates 39 protrude partly to be higher than the groove bottom face of a wire receiver part 23 by the force of a spring 49. When the wire 21 is placed, a part which has protruded to be higher than the groove bottom face of every grounding plate 39 is pressed to the wire 21 so as to be pulled, but it is pressed to the wire 21 by the force of the spring 49. As a result, the electric wire 21 which is passed through the metal wheel 11 is set to electric continuity with every grounding plate 39, and it is grounded through a route which is composed of every grounding plate 39, a piece body part 25, a track frame 17, a support member 19 and a pylon 53. Thereby, the wire 21 which is passing can be grounded surely without using a grounding roller.</p> |
