PURPOSE: To prevent contamination of an environment dut to bird droppings by inserting two or more obstructive members on a wire, which is set up just above an overhead cable and parallel to this overhead cable, and mounting the obstructive member rotatably to the wire with spaces where birds cannot perch on the wire between the obstructive members.
CONSTITUTION: Two or more obstructive members 10, formed of spherical and cylindrical or disk-shaped members or the like, are mounted to a wire 1, set up just above an overhead cable, rotatably with spaces where birds cannot perch on the cable between the obstructive members 10. Accordingly, when birds, tending to flock together, try to perch on the wire 1, they can not perch on it because the obstructive members 10 are narrowly spaced. Even when they try to perch on the obstructive members 10, they cannot perch on the members 10 because the obstructive members 10 rotate. As a result, birds are prevented from flocking on the overhead cable.
OGASAWARA OSAMU
TANAKA HITOSHI
