Drill head for glass borehole machine, has discharge opening for cool water provided in casing that surrounds circular chamber and closed by valve, where discharge opening is attached to return pipe and casing is movably fastened at sleeve

摘要

The drill head has a casing (2) movably fastened at a sleeve (1). An inner part (4) is connected with a spindle (3). Radial boreholes (12) are attached to the inner part and lead to an axial borehole (13). A circular chamber (5) is formed between the inner part and the casing and is closed by sealants (7). A cool water supply (11) discharges cool water into the circular chamber. A discharge opening (10) for the cool water is provided in the casing that surrounds the circular chamber. The discharge opening is closed by a valve (16) and is attached to a return pipe (15).