Mud motor assembly

• US 9,051,781 B2
• Filed: 05/22/2012
• Issued: 06/09/2015
• Est. Priority Date: 08/13/2009
• Status: Expired due to Fees

• Current Assignee: Smart Drilling and Completion, Inc.
• Original Assignee: Smart Drilling and Completion, Inc.
• Inventors: Vail, William Banning III
• Primary Examiner(s): Thompson, Kenneth L
• Assistant Examiner(s): WILLS III, MICHAEL R
• Application Number:
  US13/506,887
• Publication Number:
  US 20120234603A1
• Time in Patent Office: 1,113 Days
• Field of Search: 175/57, 175/93, 175/96, 175/107
• US Class Current: 1/1
• CPC Class Codes: E21B 4/02 Fluid rotary type drives

Abstract

A longer-lasting, lower cost, more powerful, all metal, mud motor than the presently available progressing cavity type mud motors for drilling boreholes into the earth. A mud motor apparatus possessing one single drive shaft that turns a rotary drill bit, which apparatus is attached to a drill pipe which provides high pressure mud to the mud motor, wherein the drive shaft receives at least a first portion of its rotational torque from any high pressure mud flowing through a first hydraulic chamber within the apparatus, and receives at least a second portion of its rotational torque from any high pressure mud flowing through a second hydraulic chamber within the apparatus. The mud motor apparatus possesses two hydraulic chambers, each having its own power stroke, and return stroke, and acting together in a controlled fashion, provide continuous power to a rotary drill bit.

Claims

1. A method to provide torque and power to a rotary drill bit rotating clockwise attached to a drive shaft of a mud motor assembly comprising at least the following steps:

a. providing relatively high pressure mud from a drill pipe attached to an uphole end of said mud motor assembly;

b. passing at least a first portion of said relatively high pressure mud through a first hydraulic chamber having a first piston that rotates a first crankshaft clockwise about its own rotation axis from its first relative starting position at 0 degrees through a first angle of at least 210 degrees, but less than 360 degrees during its first power stroke;

c. mechanically coupling said first crankshaft by a first ratchet means to a first portion of said drive shaft to provide clockwise rotational power to said drive shaft during said first power stroke; and

d. passing at least a second portion of said relatively high pressure mud through a second hydraulic chamber having a second piston that rotates a second crankshaft clockwise about its own rotation axis from its first relative starting position of 0 degrees through a second angle of at least 210 degrees, but less than 360 degrees during its second power stroke;

e. mechanically coupling said second crankshaft by a second ratchet means to a second portion of said drive shaft to provide clockwise rotational power to said drive shaft during said second power stroke; and

f. providing first control means of said first ratchet means, and providing second control means of said second ratchet means, to control the relative timing of rotations of said first crankshaft and said second crankshaft so that at the particular time that said first crankshaft has rotated from its first relative starting position through 180 degrees nearing the end of its first power stroke at 210 degrees, said second crankshaft begins its rotational motion from its relative starting position of 0 degrees were it begins its second power stroke.

2. The method in claim 1 wherein said first ratchet means is comprised of a first pawl that is flexibly attached by a first torsion rod return spring and second torsion rod return spring to said first crankshaft, and first pawl latch that is an integral portion of the drive shaft.

3. The method in claim 2 wherein said first control means is comprised of a first pawl lifter means that is an integral portion of the drive shaft that lifts said first pawl in a first fixed relation to said drive shaft.

4. The method in claim 3 wherein following the clockwise rotation of the said first crankshaft about its rotational axis through an angle of at least 210 degrees during its first power stroke, said first pawl lifter means disengages said first pawl from said first pawl latch, so that first torsion return spring returns first crankshaft in a counter-clockwise rotation to its initial starting position completing a first power stroke and first return cycle for said first crankshaft while said drive shaft continues to rotate clockwise unimpeded by the return motion of said first crankshaft.

5. The method in claim 4 wherein the first torsional energy stored in said first torsion return spring at the end of said first power stroke is obtained by said first crankshaft twisting said first torsion spring during said first power stroke.

6. The method in claim 5 wherein said first power stroke and said second power stroke are repetitiously repeated so that torque and power is provided to said clockwise rotating drive shaft attached to said drill bit, whereby said clockwise rotation is that rotation observed looking downhole toward the top of the rotary drill bit.

7. The method in claim 1 wherein said second ratchet means is comprised of a second pawl that is flexibly attached by third torsion rod return spring and fourth torsion rod return spring to said second crankshaft, and second pawl latch that is an integral portion of the drive shaft.

8. The method in claim 7 wherein said second control means is comprised of a second pawl lifter means that is an integral portion of the drive shaft that lifts said second pawl in a second fixed relation to said drive shaft.

9. The method in claim 8 wherein following the clockwise rotation of the said second crankshaft about its rotational axis through an angle of at least 210 degrees during its second power stroke, said second pawl lifter means disengages said second pawl from said second pawl latch, so that second torsion return spring returns second crankshaft in a counter-clockwise rotation to its initial starting position completing a second power stroke and second return cycle for the second crankshaft while said drive shaft continues to rotate clockwise unimpeded by the return motion of said second crankshaft.

10. The method in claim 9 wherein the second torsional energy stored in said second torsion return spring at the end of said second power stroke is obtained by said second crankshaft twisting said second torsion spring during said second power stroke.