Electric shock barrier for installing inside pipe to keep out vermin, comprises movable contact pole and separate counter pole for earthing inside of pipe

摘要

The contact pole, which is partly movable in the pipe length direction, is installed on the inside of the pipe, and the counter pole is kept separate from the contact pole and located in or on the inside of the pipe in order to earth the latter. The voltage difference between the two poles gives any animal attempting to pass over the device an electric shock. An independent claim is also included for a piece of pipe fitted with the barrier.