SUGSKYDDSANORDNING SOM SPECIELLT AER AVSEDD FOER ANVAENDNING VID BORRMASKINER

摘要

A suction attachment for use with a drilling tool includes a muzzle part forming an opening through which a drill bit extends into contact with the material to be drilled. The muzzle part has a suction aperture communicating with the drill bit opening and a suction tube connected to the suction aperture. The suction tube includes a venturi tube section having a transverse plane of smallest cross-section spaced from the suction aperture. Extending from the transverse plane is a connecting passage which terminates at its other end in a suction recess formed in the surface of the muzzle part which faces the material to be drilled. The partial vacuum generated at the venturi tube section is transmitted through the connecting passage to the suction recess for holding the attachment on the material to be drilled.