| 摘要 |
PURPOSE: A device for preventing a magpie nest on a telegraph pole is provided to easily replace a defective part by detachably combining an inner tub with an outer tub using a combination protrusion and a combination groove. CONSTITUTION: An inner tub(30) has a divided structure with the upper part and lower part which have the same shape and includes a support rib(32) which is engaged with the telegraph pole. An outer tub(40) surrounds the inner tub. The inner tub and the outer tub are detachably combined by using each combination protrusion(34,44) and each combination groove(36,46). A plurality of balls(50) are interposed to rotates the outer tub with regard to the inner tub. |
