CONDUIT TRAVERSING VEHICLE

摘要

A vehicle (1) for travelling along a conduit (2) having fluid flowing therein is described. The vehicle comprises a forward set of resilient bristles (12) and a rear set of bristles (18) which are adapted to move towards and away from the forward bristles (12). The forward bristles (12) engage the surface of the conduit (2) and apply a greater gripping force when they are moving towards the rear bristles (18) than when they are moving away from the rear bristles (18). Similarly, the rear bristles (18) apply a larger gripping force to the surface of the conduit (2) when they are moving away from the forward bristles (12) than when they are moving towards the forward bristles (12). A drive means (4) has a shaft (9) which is rotated by fluid flow, and a reverse traverse screw (14) is connected to the shaft such that rotation of the shaft (9) causes a thread follower (16) to move along the reverse traverse screw (14) first in one direction, and then the other, to move the forward (12) and rear (18) bristles towards and then away from each other. This causes the vehicle (1) to move along the conduit (2).