# US 5,341,887 A · Directional multi-blade boring head > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,341,887 A - Document ID: US5341887A - Status: Granted - Kind: A - Application number: 08/067,298 - Filed: 1993-05-25 - Granted: 1994-08-30 - Earliest claimed: 1992-03-25 - Assignees: The Charles Machine Works, Inc. - Inventors: Arthur D. Deken; Cody L. Sewell - Web page: https://patentgrep.com/patent/US5341887A ## CPC - E21B 10/08: Roller bits (E21B10/26 takes precedence; roller core bits E21B10/06; characterised by wear resisting parts E21B10/50) - E21B 7/06: Deflecting the direction of boreholes - E21B 7/064: {specially adapted drill bits therefor} - E21B 7/065: {using oriented fluid jets} - E21B 7/267: {Drilling devices with senders, e.g. radio-transmitters for position of drilling tool} - E21B 10/20: characterised by detachable or adjustable parts, e.g. legs or axles - E21B 10/54: the bit being of the rotary drag type, e.g. fork-type bits - E21B 10/60: characterised by conduits or nozzles for drilling fluids (for roller bits E21B10/18; for percussion drill bits E21B10/38) - E21B 10/602: {the bit being a rotary drag type bit with blades} - E21B 10/62: characterised by parts, e.g. cutting elements, which are detachable or adjustable (E21B10/64 takes precedence; for roller bits E21B10/20; for augers E21B10/44) - E21B 21/002: {Down-hole drilling fluid separation systems (containers comprising collecting means with a strainer E21B27/005; subsoil filtering E21B43/02; down-hole production separators E21B43/38)} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract Directional multi-blade boring heads (1000, 1050) are disclosed which have first and second blades (1030, 1032) which each define a deflecting surface (1036, 1038) for deflecting the boring head when the head is advanced without rotation. At least one intermediate blade (1034) extends between the deflecting surfaces in a three blade design. In a four blade design, a second intermediate blade (1042) extends on the side opposite the first intermediate blade (1034). The boring head is particularly effective in drilling a straight borehole through a variety of soil conditions when the boring head is simultaneously rotated and advanced along the direction of boring. ## Claims ### Claim 1 A directional multi-blade boring head for a boring machine, the boring machine capable of axially advancing and rotating a drill string about an axis of rotation underground, the drill string ending in the directional multi-blade boring head, said directional multi-blade boring head comprising: a body having a central axis of rotation; a blade assembly mounted on the body having a first blade defining a deflecting surface at an oblique angle to the central axis of rotation of the body and a second blade defining a deflecting surface at an oblique angle to the central axis of rotation of the body, the first and second blades extending at an angle relative to each other; at least one additional blade extending from the blade assembly between the deflecting surfaces; the deflecting surfaces of a first and second blade deflecting the boring head as the boring machine advances the drill string without rotation and the directional multi-blade boring head drilling a relatively straight borehole as the boring machine advances the drill string with rotation. ### Claim 2 (depends on 1) The directional multi-blade boring head of claim 1, wherein only one additional blade extends from the blade assembly. ### Claim 3 (depends on 1) The directional multi-blade boring head of claim 1 wherein two additional blades extend from the blade assembly. ### Claim 4 (depends on 1) The directional multi-blade boring head of claim 1 wherein the body mounts a fluid jet thereon to assist boring, a passage being formed in the body to supply fluid to the fluid jet. ### Claim 5 (depends on 1) The directional multi-blade boring head of claim 1 wherein each of said blades has serrated teeth. ### Claim 6 (depends on 1) The directional multi-blade boring head of claim 1 wherein each of the first and second blades extend at an oblique angle relative to the central axis of rotation of the body. ### Claim 7 A directional multi-blade boring head for a boring machine, the boring machine capable of axially advancing and rotating a drill string about an axis of rotation underground, the drill string ending in the directional multi-blade boring head, said directional multi-blade boring head comprising: a body having a central axis of rotation and a planar surface at an oblique angle to the central axis, a plane of symmetry passing through the central axis of rotation and perpendicular to the planar surface; a blade assembly mounted to the body at the planar surface and defining a first blade extending at an angle of about 60.degree. from the plane of symmetry on a first side of the plane of symmetry and a second blade extending at an angle of about 60.degree. from the opposite side of the plane of symmetry, said first and second blades each defining deflecting surfaces thereon; at least one intermediate blade extending from the blade assembly between the deflecting surfaces; the deflecting surfaces of the first and second blades deflecting the boring head as the boring machine advances the drill string without rotation and the directional multi-blade boring head drilling a relative straight borehole as the boring machine advances the drill string with rotation. ### Claim 8 (depends on 7) The directional multi-blade boring head of claim 7 wherein said intermediate blade extends along the plane of symmetry. ### Claim 9 (depends on 7) The directional multi-blade boring head of claim 7 having carbide inserts on the blades to reduce wear. ### Claim 10 (depends on 7) The directional multi-blade boring head of claim 7 wherein the body further has a fluid jet mounted therein. ### Claim 11 (depends on 7) The directional multi-blade boring head of claim 7 wherein each of the blades has serrated teeth. ### Claim 12 A directional multi-blade boring head for a boring machine, the boring machine capable of axially advancing and rotating a drill string about an axis of rotation underground, the drill string end in a directional multi-blade boring head, said directional multi-blade boring head comprising: a body having a central axis of rotation and a planar surface at an oblique angle to the central axis, a plane of symmetry passing through the central axis of rotation and perpendicular to the planar surface; a blade assembly mounted to the body at the planar surface and defining a first blade extending perpendicular to the plane of symmetry on a first side of the plane of symmetry and a second blade extending perpendicular to the plane of symmetry from the opposite side of the plane of symmetry, said first and second blades each defining deflecting surfaces thereon; at least one intermediate blade extending from the blade assembly between the deflecting surfaces and lying parallel to the planar surface; the deflecting surfaces of the first and second blades deflecting the boring head as the boring machine advances the drill string without rotation and the directional multi-blade boring head drilling a relatively straight borehole as the boring machine advances the drill string with rotation. ### Claim 13 (depends on 12) The directional multi-blade boring head of claim 12 wherein the intermediate blade extends on both sides of the deflecting surfaces. ### Claim 14 (depends on 12) The directional multi-blade boring head of claim 12 wherein the body further has a fluid jet mounted therein, the fluid jet impacting upon the intermediate blade and being deflected to assist the drilling action. ### Claim 15 (depends on 12) The directional multi-blade boring head of claim 12 wherein each of the blades has serrated teeth. ### Claim 16 (depends on 12) The directional multi-blade boring head of claim 12 wherein each of the blades has carbide inserts therein. ### Claim 17 A directional boring head for a boring machine, the boring machine capable of axially advancing and rotating a drill string about an axis of rotation underground, the drill string ending in the directional boring head, said directional boring head comprising: a body having a central axis of rotation; a deflection structure mounted on the body defining a deflecting surface at an oblique angle to the central axis of rotation of the body; at least one roller cone cutter mounted to said body; and the deflecting surface deflecting the boring head as the boring machine advances the drill string without rotation and the directional boring head drilling a relatively straight borehole as the boring machine advances the drill string with rotation. ### Claim 18 (depends on 17) The directional boring head of claim 17 having two roller cones mounted on the body. ### Claim 19 (depends on 17) The directional boring head of claim 17 wherein a fluid jet is mounted on the body, the body having a passage for flow of fluid for discharge from the jet to assist in the drilling. ### Claim 20 (depends on 19) The directional boring head of claim 19 wherein the jet is oriented to discharge a fluid at the roller cone. ### Claim 21 (depends on 17) The directional boring head of claim 17 wherein the deflecting structure and roller cone are mounted on a bit assembly removably attached to the body. ### Claim 22 (depends on 17) The directional boring head of claim 17 wherein the rotational axis of the roller cone intersects the central axis of rotation of the body.