Claims
- 1. The method of securely placing a screw-type anchor in the earth without unduly disturbing the surrounding soil, said anchor having a shank and a flight of given pitch, comprising the steps of:
- a. enveloping the anchor's shank in a tubular mandrel, said mandrel having a flight near its bottom end of substantially the same pitch as the anchor's flight, with the mandrel's flight constituting an effective continuation of the anchor's flight;
- b. placing the tip of the anchor in contact with the earth and rotating the anchor in a direction to cause its entrance into the earth, with anchor rotation being accomplished by rotating the enveloping mandrel so as to apply torsional loads to the anchor near the anchor's flight; and
- c. after the anchor has been rotated sufficiently to achieve a desired depth in the earth, rotating the mandrel in the opposite direction to cause it to separate from the anchor and to back out of the earth through substantially the same cut that was made when the anchor was turned into the earth.
- 2. The method as claimed in claim 1 wherein the leading edge of the mandrel's flight is positioned so as to abut the trailing edge of the anchor's flight, so that rotating the mandrel can impart a torsional load on the anchor through the anchor's flight.
- 3. The method as claimed in claim 1 wherein torque reaction loads recited in the two rating steps are passed to the earth through a mobile frame.
- 4. The method as claimed in claim 1 wherein an electrically powered portable torque unit is employed to rotate the mandrel, and the direction of rotation is reversible by manually flipping a switch, whereby the mandrel can be extracated from the earth without physically disconnecting the torque unit from the mandrel.
Parent Case Info
This is a division of Ser. No. 435,224 filed Jan. 21, 1974, now U.S. Pat. No. 3,896,890.
US Referenced Citations (7)
Divisions (1)
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Number |
Date |
Country |
Parent |
435224 |
Jan 1974 |
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