US4621698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Percussion boring tool
Assignee: Gas Technology Institute
•
Filing: 1985-04-16
•
Granted: 1986-11-11
•
Expires: 2005-04-16
Abstract
Abstract A percussion boring tool is disclosed for boring in the earth at an angle or in a generally horizontal direction. The tool has a steering mechanism substantially as shown in a copending patent application and a cylindrical body with overgage sleeves located over a portion of the outer body affixed so that they can rotate but cannot slide axially. The overgage areas at the front and back of the tool, or alternately, an undergage section in the center of the tool body permits a 2-point contact (front and rear) of the outer housing with the soil wall as opposed to the line contact which occurs without the undercut. The 2-point contact allows the tool to deviate in an arc without distorting the round cross-sectional profile of the pierced hole. Thus, for a given steering force at the front and/or back of the tool, a higher rate of turning is possible since a smaller volume of soil needs to be displaced.
Inventors
- 👤 Gerard T. Pittard
- 👤 William J. McDonald
- 👤 William C. Maurer
- 👤 John H. Cohen
- 👤 Gregory C. Givler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:37
CPC Classifications
E; E21; E21B; E21B4/00; E21B4/06; E21B4/14; E21B4/145; E21B47/00; E21B47/02; E21B47/022; E21B47/0228; E21B7/00; E21B7/04; E21B7/06; E21B7/068; E21B7/26; E21B7/267
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
123 words
A percussion tool for drilling holes in the soil comprising a cylindrical housing with a front end shaped for boring, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, and said front and rear portions being operable to reduce friction with the wall of the bore formed by the tool and to permit the tool to turn in its path along a shorter radius.
Claim 2
Dependent Claim
123 words
A percussion tool for drilling holes in the soil comprising a cylindrical housing with a front end shaped for boring, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, and said front and rear portions being operable to reduce friction with the wall of the bore formed by the tool and to permit the tool to turn in its path along a shorter radius.
Claim 3
Dependent Claim
39 words
A percussion tool according to claim 1 in which said housing is cylindrical, said front and rear portions of selected outside diameter comprise sleeve members secured to the outside of said housing at the front and rear ends thereof.
Claim 4
Dependent Claim
21 words
A percussion tool according to claim 2 in which said sleeve members are secured on said housing against longitudinal movement thereon.
Claim 5
Dependent Claim
26 words
A controllable percussion tool according to claim 3 in which at least one of said sleeve members is secured on said housing for rotary movement thereon.
Claim 6
Dependent Claim
37 words
A controllable percussion tool according to claim 4 in which said housing includes a friction bearing member on the outer surface thereof in bearing relation with said at least one sleeve member to permit rotary movement therof.
Claim 7
Dependent Claim
153 words
A percussion tool for drilling holes in the soil comprising a cylindrical housing with a tapered front end, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, said first and second means being cooperable to apply an asymmetric boring force, means on said housing having one position preventing rotary motion of said housing about its longitudinal axis and allowing said housing to have a predetermined curved path through the soil and another position causing said housing to rotate about its longitudinal axis to cause the same to have a straight path through the soil.
Claim 8
Dependent Claim
153 words
A percussion tool for drilling holes in the soil comprising a cylindrical housing with a tapered front end, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, said first and second means being cooperable to apply an asymmetric boring force, means on said housing having one position preventing rotary motion of said housing about its longitudinal axis and allowing said housing to have a predetermined curved path through the soil and another position causing said housing to rotate about its longitudinal axis to cause the same to have a straight path through the soil.
Claim 9
Dependent Claim
39 words
A percussion tool according to claim 6 in which said housing is cylindrical, said front and rear portions of selected outside diameter comprise sleeve members secured to the outside of said housing at the front and rear ends thereof.
Claim 10
Dependent Claim
21 words
A percussion tool according to claim 7 in which said sleeve members are secured on said housing against longitudinal movement thereon.
Claim 11
Dependent Claim
26 words
A controllable percussion tool according to claim 8 in which at least one of said sleeve members is secured on said housing for rotary movement thereon.
Claim 12
Dependent Claim
37 words
A controllable percussion tool according to claim 8 in which said housing includes a friction bearing member on the outer surface thereof in bearing relation with said at least one sleeve member to permit rotary movement thereof.
Claim 13
Dependent Claim
158 words
A percussion tool for drilling holes in the soil comprising a hollow cylindrical housing with a tapered front end, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, said first and second means being cooperable to apply an asymmetric boring force, a plurality of guide fins positioned on the exterior of said housing at the rear end thereof and having a first position permitting non-rotative movement through the soil and a second position causing said housing to rotate about its longitudinal axis on movement through the soil, and means for moving said fins between said first and second positions.
Claim 14
Dependent Claim
158 words
A percussion tool for drilling holes in the soil comprising a hollow cylindrical housing with a tapered front end, said housing having front and rear portions of a selected outside continuous constant diameter and an intermediate portion of lesser outside diameter providing two spaced continuous circumferential zones of frictional contact with the soil during boring, a first means on said front end for applying a boring force to the soil, a second means in said housing for applying a percussive force to said boring force applying means, said first and second means being cooperable to apply an asymmetric boring force, a plurality of guide fins positioned on the exterior of said housing at the rear end thereof and having a first position permitting non-rotative movement through the soil and a second position causing said housing to rotate about its longitudinal axis on movement through the soil, and means for moving said fins between said first and second positions.
Claim 15
Dependent Claim
72 words
A controllable percussion tool according to claim 11 in which said first means comprises an anvil having a striking surface inside said housing and a boring surface outside said housing comprising a cylindrical nose portion having a side face extending longitudinally from the tip at an acute angle thereto, and said second means comprises a reciprocally movable hammer positioned in said housing to apply a percussive force to said anvil striking surface.
Claim 16
Dependent Claim
39 words
A percussion tool according to claim 12 in which said housing is cylindrical, said front and rear portions of selected outside diameter comprise sleeve members secured to the outside of said housing at the front and rear ends thereof.
Claim 17
Dependent Claim
21 words
A percussion tool according to claim 13 in which said sleeve members are secured on said housing against longitudinal movement thereon.
Claim 18
Dependent Claim
26 words
A controllable percussion tool according to claim 14 in which at least one of said sleeve members is secured on said housing for rotary movement thereon.
Claim 19
Dependent Claim
37 words
A controllable percussion tool according to claim 15 in which said housing includes a friction bearing member on the outer surface thereof in bearing relation with said at least one sleeve member to permit rotary movement thereof.
References Cited (Backward Citations)
US2979141A
Cited
US3525405A
Cited
US3693731A
Cited
US3794128A
Cited
US3888319A
Cited
US3941101A
Cited
US3952813A
Cited
US4458765A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-10 | 1990-05-12 | 1990-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-10 | 1994-05-12 | 1994-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-10 | 1998-05-12 | 1998-11-11 | $7700.00 | Window Closed / Lapsed |