Apparatus for capturing axial force on an inner drive member
AssigneeThe Charles Machine Works, Inc.
InventorMax A. Metcalf
Life of this patent
Estimating the term…
Abstract
A spindle with a mechanism for transferring axial force from an inner drive assembly to an outer drive assembly. The spindle's inner drive shaft is connected to an inner member of a dual-rod pipe by a drive rod having a sliding sleeve. The sleeve is fixed rotationally with the drive shaft, but not axially. When axial force drives the drive rod toward the drive member of the spindle, the sleeve contacts a stop member which is paired to the outer drive assembly. The stop member may be a pair of dowel pins. Axial force is thereby transferred from the inner member to the outer member, allowing such forces to be absorbed by the outer member's larger drive components.
Claims19
An apparatus, comprising:
- an inner member disposed along a longitudinal axis;
- an outer member at least partially surrounding the inner member and disposed about the longitudinal axis;
- an inner drive shaft coupled to a motor;
- a hollow sleeve joined to the inner member and in sliding, torque-transmitting engagement with the inner drive shaft;
- and
- at least one pin disposed through the outer member and transverse to the longitudinal axis, configured to transmit axial force from the hollow sleeve to the outer member.
A spindle, comprising:
- an inner drive rod apparatus disposed about a longitudinal axis, comprising:
- a drive shaft;
- an inner drive rod, configured for connection to an inner member of a dual-member drill string;
- and
- a hollow sleeve, having a first end, a second end, and an internal surface, wherein the hollow sleeve is slidingly supported and rotationally coupled to the drive shaft at the internal surface of the sleeve and joined to the drive rod at the first end of the sleeve;
- a hollow outer member at least partially disposed about the inner drive rod apparatus, the outer member being independently rotatable relative to the inner drive rod apparatus;
- and
- at least one stop member supported by the outer member, configured to engage with the second end of the hollow sleeve.
An assembly for connecting a dual-member drill string to a gearbox, the dual-member drill string comprising independently rotatable inner and outer members, the assembly comprising:
- an inner assembly, connected at a first end to the gearbox and a second end to the rotatable inner member of the dual-member drill string, the inner assembly comprising:
- a drive shaft, rotatable about a longitudinal axis and having a first outer diameter;
- a drive rod configured for torque-transmitting connection to the rotatable inner member;
- and
- a hollow sleeve having a second outer diameter, the sleeve being joined to the drive rod and partially surrounding the drive shaft in a torque-transmitting relationship;
- wherein the hollow sleeve is configured to move axially relative to the drive shaft;
- an outer assembly comprising a cavity in which the drive shaft and hollow sleeve are partially housed, the cavity defining a first inner diameter, in which the first inner diameter is greater than the first outer diameter and the second outer diameter;
- and
- a stop member disposed through the outer assembly and extending into the cavity, wherein an effective inner diameter of the cavity at the stop member is greater than the first outer diameter and less than the second outer diameter.
Dependencies are inferred from the claim text.