Drill bit assembly

A bit assembly for a rotary drill having a source of gaseous fluid under pressure, the bit assembly haivng at least one bearing-mounted rotary cutting cone for drilling into a hard material, the bit assembly comprising:

• an elongated housing having a first end adapted for engagement with the drill and a second end including the at least one bearing mounted cutting cone, for engaging the material to be drilled;
• a plenum chamber within the housing for receiving a supply flow of the pressurized gaseous fluid from the gaseous fluid source;
• storage means within the housing for receiving and storing a supply of lubricating fluids;
• distribution conduit means extending between the storage means and the cutting cone bearing for permitting lubricating fluid to flow from the storage means to the cutting cone bearing;
• first conduit means communicating with the pressurized gaseous fluid flow in the plenum chamber and connected to the distribution conduit means for receiving a flow of gaseous fluid from the plenum chamber to be directed to the distribution conduit means;
• and
• means for combining the gaseous fluid from the first conduit means with the lubricating fluid within the distribution conduit.

A bit assembly for a rotary drill having a source of gaseous fluid under pressure, the bit having at least one bearing-mounted rotary cutting cone for drilling into a material, the bit assembly comprising:

• a housing having a drill end adapted for engagement with the drill and a tool end for receiving a bit having the at least one cutting cone, the at least one cutting cone being supported by bearings;
• a plenum chamber within the housing for receiving a supply flow of pressurized gaseous fluid from the gaseous fluid source;
• pressure reducing means comprising a flow restricting orifice within said plenum chamber to provide a reduced pressure and a reduced quantity of flow;
• first conduit means in fluid communication with the flow restricting orifice for directing a first reduced gaseous fluid flow from the pressure reducing means out of the housing into the area of the cutting cone forimpingement upon the material to pick up and remove dust and cuttings from the vicinity of the cutting cone;
• second conduit means comprising at least one passage through the wall of the housing and in fluid communication with the plenum chamber upstream from the flow restricting orifice for discharging a gaseous fluid flow of the pressurized gaseous fluid out of the housing remote from the cutting cone and toward the drill end of the housing, the relative sizes of the flow restricting orifice and the nozzle outlet being such that the first gaseous fluid flow is sufficient in quantity and velocity for conveying the dust and cuttings removed from the vicinity of the cutting cone into the second gaseous fluid flow, and the second fluid flow is of a high velocity from the nozzle outlet and of a quantity sufficient to combine with the first fluid flow for conveying the dust and cuttings out of the drill hole;
• storage means within the housing for receiving and storing a supply of lubricating fluid;
• distribution conduit means extending between the storage means and the bearings of the at least one cutting cone for permitting lubricating fluid to flow from the storage means to the cutting cone bearings;
• third conduit means extending from the plenum chamber to the distribution conduit means for receiving a flow of gaseous fluid from the plenum chamber;
• and
• means for combining the flow of gaseous fluid from the said third conduit means with the lubricating fluid to provide a gaseous fluid and lubricating fluid mixture in the distribution conduit means conveyed to the bearings of the cutting cone.

A bit assembly for a rotary drill having a source of gaseous fluid under pressure, the bit assembly comprising:

• a housing having an end adapted for engagement with the drill and a tool end for connection to a drill bit;
• a drill bit connected to the tool end of the housing end having at least one cutting cone supported by bearings in the bit;
• a plenum chamber within the housing for receiving a supply flow of presurized gaseous fluid from the gaseous fluid source, the bit having a bit conduit communicating with the plenum chamber and providing a continuation thereof;
• pressure reducing means comprising a flow restricting orifice within said plenum chamber to reduce the pressurized gaseous fluid flow;
• the bit conduit receiving the reduced flow for impingement upon the material in the area of the cutting cone to pick up and remove dust and cuttings from the vicinity of the cutting cone;
• storage means within the housing for receiving and storing a supply of lubricating fluid and having pressure means for forcing the lubricating fluid from the storage means;
• distribution conduit means extending between the storage means and the bearings of the at least one cutting cone for permitting lubricating fluid to flow from the storage means to the cutting cone bearings;
• first conduit means upstream of the flow restricting orifice for providing fluid communication between the pressurized gaseous fluid in the plenum chamber and the storage means for receiving the pressurized gaseous fluid to comprise the pressure means for the storage means;
• second conduit means downstream of the flow restricting orifice communication with the reduced flow in the plenum chamber and connected to the distribution conduit means for receiving a flow of the gaseous fluid from the plenum chamber to be directed to the distribution conduit means;
• means for combining the flow of gaseous fluid from the second conduit means with the lubricating fluid to provide a gaseous fluid and lubricating fluid mixture in the distribution conduit means conveyed to the bearings of the cutting cone.