Apparatus for reducing hydro-static pressure at the drill bit

An apparatus situated intermediate a mud motor and a drill bit in a rotating drill string, for reducing the hydrostatic mud pressure in the bit, the apparatus comprising:

• a. a substantially vertical outer housing attachable on its upper end to the mud motor and at its lower end to the drill bit;
• b. an internal shaft member including a flow bore therethrough rotatable within the housing and further allowing mud to be directed through the flow bore from the mud motor into the drill bit;
• c. gear members contained within the housing in gearing relation to the internal shaft member so that rotation of the internal shaft member imparts rotation to the gear members;
• d. a fan member in gearing relationship to the gear members, further including a fan body having in its lower end a plurality of fan blades which are rotated in unison with the rotation of the gearing members;
• and
• e. port means contained within the wall of the housing for allowing drilling mud drawn away from the drill bit by the rotation of the fan members to flow to an area outside of the outer housing.

An apparatus situated in a drill string between a rotating mud motor and a drill bit, comprising:

• a. an elongated housing;
• b. a shaft member coaxially aligned within a portion of the housing, the shaft member rotatable in unison with the rotation of the mud motor;
• c. fan means within the housing for drawing mud away from the drill bit as the fan means is rotated;
• and
• d. gear means intermediate the shaft member and the fan means for imparting rotation to the fan means as the shaft member is rotated
• e. port means within the wall of the housing for receiving mud drawn away from the drill bit by the rotation of the fan means for allowing mud drawn away from the drill bit by rotation of the fan means to an area exterior to the housing.