Fluid actuated down-hole drilling apparatus

Claim 2

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for by-passing fluid through said rotor passage between housing structure regions above and below said stator; and means carried by and rotatable with said rotor for selectively opening and closing said rotor passage.

Claim 3

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for bypassing fluid through said rotor passage between housing structure regions above and below said stator; valve means carried by and rotatable with said rotor responsive to the pressure of fluid pumped down the drilling string for closing said rotor passage; and means on said rotor for shifting said valve means to open position in the absence of fluid pressure pumped down the drilling string.

Claim 4

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for bypassing fluid through said rotor passage between housing structure regions above and below said stator; valve means carried by and rotatable with said rotor responsive to the pressure of fluid pumped down the drilling string for closing said rotor passage; and means on said rotor for shifting said valve means to open position in the absence of fluid pressure pumped down the drilling string.

Claim 5

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; wherein said stator has four lobes, said rotor having three lobes; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for by-passing fluid through said rotor passage between housing structure regions above and below said stator; and means carried by and rotatable with said rotor for selectively opening and closing said rotor passage.

Claim 6

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; wherein said stator has four lobes, said rotor having three lobes; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for by-passing fluid through said rotor passage between housing structure regions above and below said stator; and means carried by and rotatable with said rotor for selectively opening and closing said rotor passage.

Claim 7

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; wherein said stator has four lobes, said rotor having three lobes; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for by-passing fluid through said rotor passage between housing structure regions abOve and below said stator; valve means carried by and rotatable with said rotor responsive to the pressure of fluid pumped down the drilling string for closing said rotor passage; and means on said rotor for shifting said valve means to open position in the absence of fluid pressure pumped down the drilling string.

Claim 8

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; said stator and rotor having coacting helical lobes constantly in contact with one another and in any transverse section, whereby fluid pumped downwardly through the drilling string passes through the helical passages between said stator and rotor lobes to rotate said rotor in an orbital path around the axis of the stator; said rotor being hollow throughout a major portion of its length and having a plurality of helical lobes, said stator having one more helical lobe than said rotor; a drive shaft rotatably supported in said housing structure below said rotor and having lower connector means for attachment to a drill bit, said shaft having passage means for conducting fluid discharging from said stator to the drill bit when attached to said lower connector means; and means interconnecting said rotor and drive shaft for transmitting the rotary motion of said rotor to said drive shaft; wherein said stator has four lobes, said rotor having three lobes; said hollow rotor providing a central passage therein; said rotor having upper and lower openings communicating with said passage for by-passing fluid through said rotor passage between housing structure regions abOve and below said stator; valve means carried by and rotatable with said rotor responsive to the pressure of fluid pumped down the drilling string for closing said rotor passage; and means on said rotor for shifting said valve means to open position in the absence of fluid pressure pumped down the drilling string.

Claim 9

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between said shaft means and housing structure; axial bearing means between said shaft means and housing structure for transmitting axial loads between said housing structure and shaft means; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained, and booster piston means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space, said booster piston means having a first effective transverse area responsive to the pressure of fluid externally of said confined space, said booster piston means also having a second effective transverse area bearing against the lubricant in said confined space which is less than said first transverse area.

Claim 10

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between said shaft means and housing structure; axial bearing means between said shaft means and housing structure for transmitting axial loads between said housing structure and shaft means; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained, and booster piston means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space, said booster piston means having a first effective transverse area responsive to the pressure of fluid externally of said confined space, said booster piston means also having a second effective transverse area bearing against the lubricant in said confined space which is less than said first transverse area.

Claim 11

Apparatus as defined in claim 5; said confined space being an annular space between said shaft means and housing structure, said booster piston means defining an end of said annular space and comprising an annular piston having said second effective transverse area bearing against the lubricant and said first effective transverse area subject to the pressure of the fluid externally of said annular space.

Claim 12

Apparatus as defined in claim 5; said stator and rotor having coengaging means to provide a positive displacement hydraulic motor wherein said rotor is rotated in response to fluid under pressure pumped down the drilling string and between said rotor and stator; said rotor having passage means including upper and lower openings for by-passing fluid through said passage menas between housing structure regions above and below said stator; means on said rotor for selectively opening and closing said passage means; said shaft means having a fluid passage adapted to receive fluid from said lower opening for discharge into the drill bit.

Claim 13

Apparatus as defined in claim 5; said stator and rotor having coengaging means to provide a positive displacement hydraulic motor wherein said rotor is rotated in response to fluid under pressure pumped down the drilling string and between said rotor and stator; said rotor having passage means including upper and lower openings for by-passing fluid through said passage means between housing structure regions above and below said stator; means on said rotor for selectively opening and closing said passage means; said shaft means having a fluid passage adapted to receive fluid from said lower opening for discharge into the drill bit; said means on said rotor comprising valve means responsive to the pressure of fluid pumped down the drilling string for closing said passage means, and spring means acting between said rotor and valve means for shifting said valve means to open position in the absence of fluid pressure pumped down the drilling string.

Claim 14

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between saId shaft means and housing structure; axial bearing means between said shaft means and housing structure for transmitting axial loads between said housing structure and shaft means; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained; and booster piston means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space; said confined space being an annular space between said shaft means and housing structure, said booster piston means defining an end of said annular space and comprising an annular piston having a first portion bearing against the lubricant and a second portion subject to the pressure of the fluid externally of said annular space, said second portion having a greater transverse pressure responsive annular area than the transverse annular area of said first portion.

Claim 15

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between saId shaft means and housing structure; axial bearing means between said shaft means and housing structure for transmitting axial loads between said housing structure and shaft means; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained; and booster piston means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space; said confined space being an annular space between said shaft means and housing structure, said booster piston means defining an end of said annular space and comprising an annular piston having a first portion bearing against the lubricant and a second portion subject to the pressure of the fluid externally of said annular space, said second portion having a greater transverse pressure responsive annular area than the transverse annular area of said first portion.

Claim 16

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between said shaft means and housing structure; said shaft means having a lower thrust shoulder; a first thrust shoulder on said housing structure; first thrust bearing means engaging said first shoulder; a second thrust shoulder on said housing structure; second thrust bearing means engaging said second shoulder; yieldable means engaging said first bearing means; load transmitting means engaging said yieldable means and lower shoulder to transmit drilling weight from said housing structure through said first shoulder, first bearing means and yieldable means to said lower shoulder; said second bearing means being initially ineffective to transmit drilling weight to said load transmitting means and becoming effective to transmit drilling weight to said load transmitting means upon predetermined yielding of said yieldable means when subjected to a load exceeding a predetermined value.

Claim 17

Fluid motor apparatus for drilling a bore hole in a formation: a housing structure having upper connector means for attachment to a tubular drilling string extending to the top of the bore hole, said structure including a stator; a rotor within said stator; shaft means connected to said rotor for attachment to a drill bit to rotate the same; radial bearing means between said shaft means and housing structure for transmitting radial forces between said shaft means and housing structure; said shaft means having a lower thrust shoulder; a first thrust shoulder on said housing structure; first thrust bearing means engaging said first shoulder; a second thrust shoulder on said housing structure; second thrust bearing means engaging said second shoulder; yieldable means engaging said first bearing means; load transmitting means engaging said yieldable means and lower shoulder to transmit drilling weight from said housing structure through said first shoulder, first bearing means and yieldable means to said lower shoulder; said second bearing means being initially ineffective to transmit drilling weight to said load transmitting means and becoming effective to transmit drilling weight to said load transmitting means upon predetermined yielding of said yieldable means when subjected to a load exceeding a predetermined value.

Claim 18

Apparatus as defined in claim 10; and a third thrust bearing between said housing structure and shaft means for axially supporting said shaft means from said housing structure.

Claim 19

Apparatus as defined in claim 10; said yieldable means comprising a yieldable ring adapted to deflect when subjected to axial loads.

Claim 20

Apparatus as defined in claim 10; and a third thrust bearing between said housing structure and shaft means for axially supporting said shaft means from said housing structure; said yieldable means comprising a yieldable ring adapted to deflect when subjected to axial loads.

Claim 21

Apparatus as defined in claim 10; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained; and booster means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space.

Claim 22

Apparatus as defined in claim 10; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearing means are contained; and booster means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space; said confined space being an annular space between said shaft means and housing structure, said booster means defining an end of said annular space and comprising an annular piston having a first portion bearing against the lubricant and a second portion subject to the pressure of the fluid externally of said annular space.

Claim 23

Apparatus as defined in claim 10; means providing a confined space adapted to contain a liquid lubricant and in which said radial bearing means and axial bearIng means are contained; and booster means for subjecting the liquid lubricant to a greater unit pressure than the unit pressure externally of said confined space; said confined space being an annular space between said shaft means and housing structure, said booster means defining an end of said annular space and comprising an annular piston having a first portion bearing against the lubricant and a second portion subject to the pressure of the fluid externally of said annular space, said second portion having a greater transverse pressure responsive annular area than the annular area of said first portion.