Helical screw pile and soil displacement device with curved blades

• US 9,416,513 B2
• Filed: 10/25/2013
• Issued: 08/16/2016
• Est. Priority Date: 10/25/2013
• Status: Active Grant

• Current Assignee: Hubbell, Inc.
• Original Assignee: Hubbell, Inc.
• Inventors: Kemp, Timothy Michael, Downey, Shawn David, Hawkins, Kelly Suzanne
• Primary Examiner(s): Fiorello, Benjamin
• Assistant Examiner(s): Armstrong, Kyle
• Application Number:
  US14/063,107
• Publication Number:
  US 20150117960A1
• Time in Patent Office: 1,026 Days
• Field of Search: 405/252.1, 405/253, 405/255
• US Class Current: 1/1
• CPC Class Codes: E02D 5/56 Screw piles placing piles by screwing down E02D7/22
• CPC Class Codes: E02D 5/72 Pile shoes
• CPC Class Codes: E02D 5/801 driven by screwing
• CPC Class Codes: E21B 7/26 Drilling without earth removal, e.g. with self-propelled burrowing devices E21B7/30 takes precedence

Abstract

A helical screw pile having a soil displacement device (lead displacement plate) on its shaft above at least one helical plate, which pulls the pile into the ground when the shaft is rotated. The lead displacement plate has a disk that carries at least two curved, axially extending bottom blades, which preferably extend beyond the disk periphery. The axial height of the blades preferably is greater than the axial pitch of the helical plate(s) divided by the number of blades. The top of the disk has an axially extending adapter ring that defines an annular seat for centering a tubular casing. Extension displacement plates can be used between extension shafts for centering additional tubular casings.

Claims

1. A soil displacement device for penetrating and forming a void in the ground when rotated about a central longitudinal axis by a helix-bearing shaft, the device comprising:

a disk having a periphery, a top, a bottom and a central through-opening for receiving a shaft; and

at least two blades disposed substantially completely below the top of the disk, each blade projecting substantially axially from said bottom to a free distal axial edge and curving outward from near said opening to at least said periphery, each said blade having concave trailing face and a convex leading face and an end portion spaced radially outward from said opening to displace soil radially outward and enhance soil packing when rotated in the ground penetrating direction, said end portion of each said blade defining a trailing end of said blade extending beyond a periphery of said disk where the end portion is substantially normal to the radius of the disk and, said convex leading face of said blade extending parallel to an axis of said center through-opening and said trailing face sloping toward said disk, and where said free distal axial edge of each of said blades are substantially coplanar and lie in a plane oriented substantially perpendicular to a center axis of said disk.

2. The soil displacement device of claim 1, wherein the radius of curvature of each blade is non-uniform.

3. The soil displacement device of claim 2, wherein the radius of curvature of each blade is larger near the opening and near the disk periphery than its radius of curvature in an intermediate portion therebetween.

4. The soil displacement device of claim 1, wherein the thickness of each blade tapers toward its distal edge.

5. The soil displacement device of claim 4, wherein the bottom of the disk tapers toward its periphery.

6. The soil displacement device of claim 1, wherein the distal edges of the blades are substantially coplanar and substantially normal to said axis.

7. The soil displacement device of claim 1, further comprising an adapter ring extending axially from the top of the disk inboard of the disk periphery and defining an annular seat on the disk for centering a tubular casing.

8. The soil displacement device of claim 7, wherein the adapter ring has an outer face that tapers toward a distal end thereof.

9. The soil displacement device of claim 1, wherein, the distal edge of each of said blades is substantially perpendicular to said longitudinal axis.

10. The soil displacement device of claim 1, wherein the distal edge of each of said blades are substantially coplanar with each other.

11. A helical screw pile for penetrating the ground and forming a support, the screw pile comprising:

a shaft having a longitudinal axis and a bottom end;

at least one helical plate on said shaft near said bottom end, said helical plate having a leading, ground engaging edge and a trailing edge; and

a soil displacement device on said shaft above said at least one helical plate, the soil displacement device including;

a disk having a periphery, a top, a bottom and a central opening through which the shaft extends; and

at least two blades disposed substantially completely below the top of the disk, each blade projecting substantially axially from said bottom to a free distal axial edge to a free distal edge and curving outward from near said opening to at least said periphery, each said blade having a convex leading face with an end portion spaced radially from said opening and being curved to displace soil radially outward and enhance soil packing when said shaft is rotated in the ground penetrating direction, the blades extending beyond the disk periphery, and where an end portion of the leading face of each blade extending beyond the periphery of the disk is substantially normal to a radius of the disk, and where said free distal axial edge of each of said blades are substantially coplanar and lie in a plane oriented substantially perpendicular to a center axis of said disk.

12. The helical screw pile of claim 11, wherein the soil displacement device has an adapter ring extending axially from the top of the disk inboard of the disk periphery and defining an annular seat on the disk for supporting and centering a tubular casing surrounding the shaft.

13. The helical screw pile of claim 12, wherein the shaft includes a plurality of sequentially connected shaft segments including a lead shaft at the bottom and extension shafts thereabove, wherein the at least one helical plate is carried by the lead shaft and the soil displacement device is carried by either the lead shaft or one of the extension shafts, further comprising at least one extension displacement plate carried by the shaft above the soil displacement device, the extension displacement plate having oppositely facing annular seats for centering tubular casings surrounding the shaft.

14. The helical screw pile of claim 11, wherein the central opening and the shaft are substantially square, further comprising a substantially square insert in the central opening having a substantially square aperture sized to closely receive the shaft.

15. The soil displacement device of claim 11, wherein the distal edge of each of said blades are substantially perpendicular to said longitudinal axis.

16. A helical screw pile for penetrating the ground and forming a support, the screw pile comprising:

a shaft having a longitudinal axis and a bottom end;

at least one helical plate on said shaft near said bottom end, said helical plate having a leading, ground engaging edge and a trailing edge; and

a soil displacement device on said shaft above said at least one helical plate, the soil displacement device including;

a disk having a periphery, a top, a bottom and a central opening through which the shaft extends; and

at least two blades extending axially from said disk and disposed completely below the top of the disk, each blade having a free distal axial edge and curving radially outward from near said opening, each said blade having a convex leading ground engaging face being curved to displace soil radially outward and enhance soil packing when said shaft is rotated in the ground penetrating direction, each blade having an end portion with an axially extending end trailing edge oriented beyond the periphery of said disk, and where said end portion of the leading face of each blade extends beyond the periphery of the disk is substantially perpendicular to a radius of the disk, and where said free distal axial edge of each of said blades are substantially coplanar and lie in a plane oriented substantially perpendicular to a center axis of said disk; and

an extension displacement plate on said shaft and spaced above said soil displacement device, said soil displacement plate having a central disk with a peripheral edge, first integral adapter ring extending axially from a first side of said central disk and second integral adapter ring extending axially form a second side of said central disk.