Pullback system for drilling tool

Patent metadata

Field	Value
Publication number	US-10900294-B2
Application number	US-201916526032-A
Country	US
Kind code	B2
Filing date	Jul 30, 2019
Priority date	Aug 22, 2018
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

A pullback system for installing product in a hole includes a rotary drill bit having a plurality of cutter elements, and a pullback device that is attachable to the rotary drill bit without disassembling the rotary drill bit or removing the rotary drill bit from a drill string. The pullback device includes a frame member and a plurality of anchor arms. Each anchor arm has a first end coupled to the frame member and a second end. Each anchor arm is configured to extend between adjacent cutter elements of the rotary drill bit. An attachment location can be used to attach product to the pullback device.

First claim

What is claimed:

1. A pullback system for installing product in a hole, the system comprising:
a rotary drill bit having a main body with a central axis, and a plurality of cutter cones rotatably mounted to the main body, each cutter cone having a conical cutting surface; and
a pullback device attachable to the rotary drill bit without disassembling the rotary drill bit or removing the rotary drill bit from a drill string, the pullback device having:
a frame member;
a plurality of anchor arms, each anchor arm having a first end coupled to the frame member and a second end having a radial portion extending inwardly toward the central axis; and
an attachment location on the pullback device configured to attach the product to the pullback device;

wherein each radial portion engages adjacent cutter cones of the rotary drill bit when positioned between two opposing conical cutting surfaces to mount the pullback device to the rotary drill bit.

2. The pullback system of claim 1 , wherein the pullback device includes three anchor arms equally spaced between the cutter cones of the rotatory drill bit.

3. The pullback system of claim 1 , wherein the at least one attachment location attaches the pullback device to a swivel device, the swivel device configured to attach the product to the pullback device and to prevent the product from rotating inside the hole when the pullback device is pulled back through the hole.

4. The pullback system of claim 1 , wherein each anchor arm is pivotally connected to the frame member at the first end, and wherein each anchor arm includes a feature having a locking surface between the first end and the second end; and
the pullback system further includes a locking device insertable through an opening in the frame member, the locking device having a first end that surrounds the locking surfaces of the anchor arms so that the plurality of anchor arms cannot pivot with respect to the frame member, and the locking device having a second end that includes the attachment location.

5. The pullback system of claim 4 , further comprising a pin, and wherein the locking device includes a bore between the first end and the second end, and the pin is insertable in the bore for restraining the locking device within the frame member.

6. The pullback system of claim 4 , wherein the locking device includes a hollow cylindrical body that is open on the first end and closed on the second end, and wherein the locking surfaces of the anchor arms are surrounded by the cylindrical body at the first end when the locking device is inserted through the opening in the frame member.

7. The pullback system of claim 4 , wherein each locking surface is substantially parallel to a longitudinal axis of the respective anchor arm.

8. The pullback system of claim 4 , wherein the anchor arms are pivotable with respect to the frame member when the locking device is not inserted in the opening in the frame member such that the second ends can engage and disengage adjacent cutter cones of the rotary drill bit.

9. The pullback system of claim 1 , wherein each anchor arm is pivotally connected to the frame member at the first end, and the second end is configured to engage adjacent cutter cones of the rotary drill bit and to apply a radial pullback force to a rotation axis of each cutter cone.

10. The pullback system of claim 1 , wherein the radial portions of the anchor arms each fit in an open gap between a drill bit base and adjacent cutter cones of the rotary drill bit.

11. The pullback system of claim 1 , wherein portions of the anchor arms are configured to extend between adjacent cutter cones of the rotary drill bit in a direction parallel to the drill bit central axis.

12. The pullback device of claim 1 , wherein each of the plurality of anchor arms is pivotally connected at the first end to the frame member to be pivotable between an expanded position and a constricted position, and in the constricted position, portions of the anchor arms are configured to extend between adjacent cutter cones of the rotary drill bit in a direction parallel to the drill bit central axis.

13. A pullback device comprising:
a frame member;
a plurality of anchor arms, each anchor arm pivotally connected to the frame member at a first end, and having a second end configured to engage a rotary drill bit and to apply a pullback force to the rotary drill bit, each anchor arm configured to extend between adjacent cutter elements of the rotary drill bit and further having a feature that includes a locking surface between the first end and the second end; and
a locking device insertable through an opening in the frame member, when inserted, the locking device having a first end that surrounds the locking surfaces of the anchor arms such that the plurality of anchor arms cannot pivot with respect to the frame member, and the locking device having a second end that includes an attachment location configured to attach a product to the pullback device.

14. The pullback device of claim 13 , wherein the pullback device includes three anchor arms equally spaced circumferentially around the frame member.

15. The pullback device of claim 13 , wherein the second end of each anchor arm is configured to fit in a gap between a drill bit base and adjacent cutter cones that define the cutter elements of the rotary drill bit.

16. The pullback device of claim 13 , wherein the locking surface of each anchor arm is substantially parallel to a longitudinal axis of the respective anchor arm.

17. The pullback device of claim 13 , further comprising a pin, and wherein the locking device includes a bore between the first end and the second end, and the pin is insertable in the bore for restraining the locking device within the frame member.

18. The pullback device of claim 13 , wherein the locking device includes a hollow cylindrical body that is open on the first end and closed on the second end, and wherein the locking surface of each anchor arm is surrounded by the cylindrical body at the first end when the locking device is inserted through the opening in the frame member.

19. The pullback device of claim 13 , wherein the attachment location is an eyelet for attaching the pullback device to a swivel device, and the swivel device is configured to attach the product to the pullback device and to prevent the product from rotating inside the hole when the pullback device is pulled back through the hole.

20. A pullback system for installing product in a hole, the system comprising:
a rotary drill bit having a plurality of cutter cones; and
a pullback device attachable to the rotary drill bit without disassembling the rotary drill bit or removing the rotary drill bit from a drill string, the pullback device having:
a frame member;
three anchor arms equally spaced about the frame member, each anchor arm having a first end pivotally coupled to the frame member and a second end configured to fit in an open gap between a drill bit base and adjacent cutter cones of the rotary drill bit, each anchor arm having a feature that includes a locking surface between the first end and the second end; and
a locking device insertable through an opening in the frame member, when inserted, the locking device having a first end that surrounds the locking surfaces of the anchor arms such that the three anchor arms cannot pivot with respect to the frame member, and the locking device having a second end that includes an attachment location configured to attach a product to the pullback device.

Assignees

• Vermeer Mfg Co

Inventors

• Dorin Tyler J
• Kreimeyer Andrew J

Classifications

• E21B7/046 Primary

  horizontal drilling (drilling with mechanical conveying means E21B7/003) · CPC title

• B27B27/02

  arranged laterally and parallel with respect to the plane of the saw blade · CPC title

• B27B27/06

  arranged angularly with respect to the plane of the saw blade, e.g. for mitring {(devices for mitring wood B27G5/00)} · CPC title

• E21B12/00 Primary

  Accessories for drilling tools · CPC title