US2973065A - Earth anchor - Google Patents

Description

Feb. 28, 1961 w. J. CORDES EARTH ANCHOR 2 Sheets-Sheet 1 Filed July 22, 1955 f/GJ INVENTOR. WILL/AM J CORDES Feb. 28, 1961 w. J. CORDES EARTH ANCHOR 2 Sheets-Sheet 2 Filed July 22, 1955 IN VEN TOR. VV/LL/AM J CORDES ATTORNEYS United States Patent EARTH ANCHOR William J. Cordes, 330 F St., Bakersfield, Calif.

Filed July 22, 1955, Ser. No. 523,666

6 Claims. (Cl. 189-90) This invention relates to earth anchors, and more particularly to a retrievable earth anchor adapted primarily to be temporarily used for the guying of such as oil well derricks, radio and television transmitter towers, and the like.

An object of the invention is to provide an earth anchor which will maintain its anchoring position within a back-filled ground hole against a great amount of centrally applied force tending to raise it, but which may be relatively readily retrieved, or pulled free, by a lifting force noncentrally applied to it.

A further object of the invention is to provide an earth anchor having a primary, or anchoring, cable and a secondary, or retriever cable, with said cables having points of attachment to the anchor such that said anchor will maintain its position within a back-filled ground hole when a high degree of pulling force is applied to said anchoring cable, and such that said achor may be readily pulled out of said hole by a pulling force applied to said retriever cable.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the drawings forming part of this specification, and in which:

Fig. l is an end view in elevation of the earth anchor;

Fig. 2 is a side view in elevation of the earth anchor;

Fig. 3 is a top plan view of the anchor;

Fig. 4 is a view in elevation showing the achor being lowered into a ground hole specially formed to receive it; and

Fig. 5 is a view in elevation showing the anchor during the course of being retrieved.

With reference to the drawings, the anchor consists of a steel plate having straight sides 12 and rounded ends 14, a bail-like rod 16 of inverted V-shape having its ends 18 welded to plate 10, an anchoring cable 21 having a clevis 22 secured thereto, a pin 24 removably attached to the clevis 22, as by a cotter pin 26, and securing the clevis to rod 16, an eye 28 of inverted U-shape welded to plate 10, a retriever cable 30 having a clevis 32 secured thereto, and a pin 34 removably attached to the clevis 32, as by a cotter pin 36, and securing said clevis to eye 28. An a-rcuate rod piece 38, having its ends welded to rod 16, encloses pin 24, thereby serving to centrally position the cable 20 with respect to plate 10. A vertically disposed rod 40, having its ends welded to rod piece 38 and plate 10, serves as a reinforcement strut therebetween.

The plate 10 is slightly cambered, i.e. the ends 14 thereof are disposed at a higher level than the mid-portion thereof. With a plate of some 46 inches in length, the ends 14 are disposed approximately 1 inch above the level of the transverse center line of the plate. It will also be noted that the eye 28 is disposed adjacent one side of one of the ends 14, and that, with reference to Fig. 3, it is angularly disposed with respect to the cable tie rod 16.

A ground hole 42 is bored to receive the anchor. This 2,973,065 Patented Feb. 28, 1961 the plate 10 on the bottom of the hole in the positional attitude which the anchor has in Fig. 2. The hole is then back filled and the loose earth is tamped down.

Three or more of these earth anchors are usually employed for the guying of an oil derrick, tower, or the like, with the achoring cables 20 being attached to the particular structure to be guyed.

The vertical component of the guying load on a cable 29 tends to pull the anchor upwardly out of the hole 42, but this force is effectively resisted by the anchor, up to the failure point of one of the elements of the anchor and cable assembly, by the fact that the back-filled earth tends to be wedged by the plate 10 against the two upwardly and inwardly directed side walls of hole 42. The camber of plate 10 is a further factor which enhances the holding power of the anchor.

When it is desired to remove the earth anchor, this is readily done, without removing the back fill from hole 42, by first disconnecting cable 20 from the structure being guyed and by then connecting an A-frame, or crane, or the ilke, to the retriever cable 30. The force applied to this cable acting through the point of attachment of the cable with plate 10 moves the cable-connected end of the plate upwardly and at the same time the plate is tilted. This decreases the earth holding pressure applied to the plate, and the end result is that the plate is moved end-wise and edge-wise in a knifing action upwardly through the back fill and out of the hole.

While a specific embodiment of the invention has been shown and described, it is to be understood that all substantial equivalents thereof are within the spirit and scope of the invention.

What is claimed is:

1. An earth anchor adapted to be disposed within a back-filled ground hole comprising an elongated plate having ends and sides, a cable pivotally connected to said plate substantially centrally thereof and a second cable having an ofi-center permanent and pivotal connection with said plate adjacent one end and one side thereof and so positioned that when an upward pulling force is applied to said second cable said plate will tend to move end-wise and edge-wise through the back-fill of the ground hole.

2. An earth anchor comprising an elongated plate having straight sides and rounded ends, a first cable, means forming a pivotal connection between said cable and approximately the mid-point of said plate, a second cable, and means forming a permanent and pivotal connection between said second cable and said plate at a point adjacent one of said sides and one of said ends.

3. An earth anchor as set forth in claim 2, said plate being slightly cam-bered so that said ends of said plate are disposed above the transverse median line thereof.

4. In combination, a ground hole frusto-conical in profile, an elongated plate having end edges and side edges disposed at the bottom of said hole, a first cable and means forming a connection between said cable and approximately the mid-point of said plate, a second cable, means forming an off-center connection between said second cable and said plate adjacent an end edge and a side edge of said plate, such that when an upward pulling force is applied to said second cable said plate will tend to move end-wise and edge-wise upwardly out of said hole, and back-fill within said hole.

5. The combination set forth in claim 4, said plate being slightly cambered so that the ends thereof are disposed above the transverse median line thereof.

6. A retrievable earth anchor comprising a plate adapted to be horizontally disposed Within the ground, said plate having side edges and end edges and being longer than it is wide, first means extending upwardly from said plate adapted to be attached to an aboveground object to be anchored, said means being connected to said plate at a point disposed substantially equidistantly between said side edges and between said end edges, and second means extending upwardly from said plate to above-ground level whereby said plate may be pulled upwardly out of the ground when said first 4 means is not attached to an object to be anchored, said second means being permanently and pivotally connected to said plate at a point disposed closely adjacent one of said end edges and disposed substantially closer to one of said side edges than to the other, said point of connection between said plate and second means being so located that when an upward pulling force is applied to said second means said plate will tend to tilt to dispose the side edge which is closer to said second means at a higher level than the other side edge and to dispose the end edge which is adjacent said second means at a higher level than the other end edge.

Great Britain May 23, 1891 Norway Nov. 6, 1905

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