Rock drill tip holder

Claim 1

A DUST COLLECTING ROCK DRILL CUTTING TIP HOLDER HAVING A GENERALLY CYLINDRICAL BODY AND A HEAD AT ITS UPPER END INTEGRAL THEREWITH, THE BODY HAVING A LOWER END ADAPTED TO BE JOINED TO THE UPPER END OF A VERTICAL TUBULAR DRILL STEM OF THE SAME DIAMETER AS SAID BODY AND ROTATABLE IN A PREDETERMINED DIRECTION, SAID BODY BEING PROVIDED WITH AN AXIAL BORE EXTENDING UPWARD IN IT FROM SAID LOWER END, THE SIDE OF THE BODY HAVING A PAIR OF DIAMETRICALLY OPPOSITE LONGITUDINAL INLET SLOTS THERETHROUGH OPENING INTO SAID BORE, SAID HEAD BEING PROVIDED WITH AN UPWARDLY AND RADIALLY OPENING TRANSVERSE VERTICAL SLOT IN THE CENTRAL LONGITUDINAL PLANE OF THE INLET SLOTS FOR RECEVING A REMOVABLE ROCK-CUTTING INSERT TIP, THE PORTIONS OF THE HEAD AT OPPOSITE SIDES OF THE TRANSVERSE SLOT FORMING THE SIDE WALLS THEREOF, EACH OF SAID SLIDE WALLS EXTENDING FROM A DIFFERENT END OF THE TRANSVERSE SLOT INWARDLY ALONG ITS TRAILING SIDE PAST THE CENTER OF THAT SLOT BUT BEING SPACED FROM THE OPPOSITE END OF THE SLOT, THE INNER END PORTIONS OF THE SIDE WALLS OVERLAPPING EACH OTHER AND HAVING A PAIR OF ALIGNED PIN-RECEIVING OPENINGS THERETHROUGH, AND THE HOLDER HAVING A FLAT INCLINED SURFACE EXTENDING ALONG ONLY THE LEADING EDGE OF EACH INLET SLOT FROM A POINT NEAR ITS LOWER END UPWARD ACROSS THE INNER END OF THE ADJOINING SIDE WALL OF THE TRANSVERSE, SLOT, THE UPPER PORTIONS OF SAID INCLINED SURFACES FORMING THE INNER END SURFACES OF SAID WALLS.