Importance

Loading Importance Indicators...

Abstract

A top head drive cooling system is provided for an earth drilling machine of the type having a mast, a top head drive assembly mounted for movement along the mast, a quill included in the top head drive assembly, and an electric motor for rotating the quill. This cooling system includes an air duct mounted to the mast and defining a slot extending along the mast. The slot is sealed by a pair of flexible resilient lips which bridge the slot, and a blower is situated at ground level to blow cooling air into the air duct. A conduit is provided on the top head drive assembly, and the conduit extends between the lips into the air duct and conducts air from the air duct to the electric motor. The portion of the conduit which extends into the air duct is preferably tapered at both ends in order to provide a sliding seal against the lips. A position measuring system is coupled to the conduit and is positioned within the air duct.

Loading the Abstract Image...

First Claim