US2658590A

US2658590A - Expanding earth anchor

Info

Publication number: US2658590A
Application number: US248250A
Authority: US
Inventors: William L Hollander
Original assignee: AB Chance Co
Current assignee: AB Chance Co
Priority date: 1951-09-25
Filing date: 1951-09-25
Publication date: 1953-11-10
Anticipated expiration: 1970-11-10

Description

NOV. 10, 1953 w, HOLLANDER 2,658,590

EXPANDING EARTH ANCHOR Filed Sept. 25, 1951 2 Sheets-Sheet 1 IN V EN TOR.

NOV. 10, 1953 w HOLLANDER 2,658,590

EXPANDING EARTH ANCHOR Filed Sept. 25, 1951 k 2 Sheets-Sheet 2 IN V EN TOR.

William Z. ffaZla zzaer Patented Nov. 10, 1953 UNITED STATES PTENT OFFICE A. B. Chance Compan poration of Missouri y, Centralia, Mo., a cor- Application'September 25, 1951, Serial N 0. 248,250

3 Claims. 1

The present invention relates to expanding earth anchors, and is particularly concerned with expanding anchors adapted to be constructed of sheet metal, such as steel.

One of the object of the invention is the provision of an expanding anchor which develops a higher holding power than the corresponding anchors of the prior art, utilizing the same amount of steel.

Another object of the invention is the provision of an improved steel expanding anchor which is more economical in the use of steel, and which is simple in construction and involves simpler methods of manufacture and simpler dies than the devices of the prior art.

Another object of the invention is the provision of improved steel expanding anchors which can be collapsed into a smaller space than the devices of the prior art, and which can, therefore, be installed in a smaller hole, and which also expand to a larger radius, engaging a wider area of undisturbed earth, thereby increasing the holding power.

Another object of the invention is the provision of improved steel expanding anchors, the blades of which penetrate the earth more easily, and which include a multiplicity of blades, so that the holding power may be unaffected by the failure of one or more blades striking rocks or other obstructions, since there are a multiplicity of other blades, resulting in a large holding power.

Another object of the invention is the provision of improved blades for steel expanding anchors, which utilize the sheet steel in such manner as to provide maximum strength and maximum penetrating power, while involving a minimum amount of waste.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the two sheets of drawings accompanying this specification,

Fig. 1 is a side elevational view of the anchor and guy rod assembly before expansion of the anchor;

Fig. 2 is a side elevational view in partial section, showing the anchor in expanded condition;

Fig. 3 is a plan view of the pattern for the anchor blades;

Fig. 4 is a plan view, showing one of the blades in a flat condition, after it has been shaped;

Fig. 5 is a side elevational view of the blade of 55 Fig. 4;

Fig. 6 is a side elevational view of one of the blades, after it has been bent to the collapsed form of the anchor assembly, but before it has been assembled with other blades and the expander;

Fig. 7 is a sectional view, taken on the plane of the line 71 of Fig. 4, looking in the direction of the arrows;

Fig. 8 is a section-a1 view, taken on the plane of the line 8-5 of Fig. 4, looking in the direction of the arrows;

Fig. 9 is a fragmentary plan view of another blade pattern, showing an alternative form of blade end.

Referring to Figs. 1 and 6, the anchors embodying the invention preferably include an expanding member It and an expander ll, these being assembled with a guy rod [2 and a nut [3. The expander ll is preferably circular in shape, having a substantially cylindrical side wall M joined to a partially spherical or frusto-conical top wall.

The top wall has a central bore [5 for passing the guy rod, below which there is located a sheet metal nut retainer It, having a registering aperture. The nut retainer It comprises a strip of steel, which may be as wide as the nut I3, and which has its body welded to the bottom of the expander II at the aperture l5, and has a pair of side flanges l'l traversing the nut and bent over at I8 under the nut.

The guy rod 12 may pass between the flanges 18; but the flanges I! hold the nut against turning, and the flanges it hold the assembly against sliding upward on the guy rod.

The expanding anchor assembly 10 preferably consists of a plurality of blade units 20 of the type shown in Fig. 6. Each of these has a flat or plane central body 2|, which, as shown in Fig. 4, is substantially hexagonal in shape. Thus the body 2| has a pair of

edges

22, 23 at an angle of degrees to each other on each side; and the body supports the blades 24 and 25, which extend from the other two sides.

Referring to Fig. 3, this is the pattern for the blades, which may be cut out of stock of standard width. The pattern is formed with the central hexagonal body portion 2| and with the

blade portions

26 and 21, each of which has a pair of

parallel sides

28, 29, and a curved end 30.

The present anchor may also be made with a square body and with four blades on two blade units; or on an octagon, or any even number of blades.

The ends 30 may be formed with tie wire apertures 3| in the opposite corners at the same time the blank is punched out of the metal stock.

The blade portions 26 and '21 taper at 32 toward the body 2| and are joined to the body by the narrow portions 33. The narrower portions 33 are naturally the easiest points at which to bend the blades; and this bending takes place in the formation of the unit '20 and in the expanding of the anchor.

Each blank has a central aperture 34 in its body 2| for passing the guy rod; and after the blanks are punched out, as shown in'Fig. 3, they are formed by stamping, as shown in Figs. 4 and 5. In this operation each blade portion 7.6, 21 is formed into the blades 24 and 25, having the longitudinally extending, oval, bulging ribs 35, extending substantially the full length of the blade and protruding upward.

At the same time the body 36 of each blade is given a downward curve in the middle, making it upwardly concave and downwardly convex, except for the rib 25, which bulges from the top.

At the same time the corners Bl between the main blade portion 25 and the tapered portion 32 are turned up, forming laterally tapered reinforcing flanges 38 (Fig. 4),, further stiffening the blade at that portion, near the body 24.

The curved ends .30 of the blades are preferably beveled .at these ends .36, as shown in Fig. 4, to sharpen these cutting edges.

Since the central body 21 of each blade unit is hexagonal, when the blades have been :bent down along the line 33, there is space on each body for passing the blades of two other such units, with the blades overlapping.

Due to the narrowness of the present blades, the blades can be bent .down .to almost right angle position; and due to their curvature, the lower ends turn outward into engagement with the upper corner 39 of the expander I.

Three of the blade units of Fig. 6 may then be assembled, as shown in Fig. 1, with their bodies overlapping and their blades disposed around the sides of the resulting hexagon, which is formed of three layers of steel. These three bodies may be welded together, if desired; but in some embodiments of the invention they need only be assembled and held by having the outermost blade unit tied to the expander l I by tie wires 40. The tie wires pass through holes in the expander H and through the holes 3| in the uppermost blade unit.

Fig. 7 shows the section of the blades along the line through the reinforcing flanges 38,.

Fig. 8 shows the section of the blades at the wider portion along the line 88. By turning up the reinforcing flanges 38 the blades may be brought closer together at the top; and the size of the assembled anchor is reduced so that it may be used in a smaller hole than the corresponding anchors of the prior art.

Referring to Fig. 9, this shows an alternative end formation 4| on the end of a blade, in which the two beveled end portions 4| join at an apex 42.

The operation of the present anchor is as tollows. The anchor is assembled with the guy rod and nut, the rod being threaded into the nut, as shown in Fig. 2; and the assembly then looks as shown in Fig. l. The .hole is dug in the :ground at an angle corresponding to the angle of "the guy or cable which is to be attached to the guy rod.

Using the guy rod as a handle, the blade assembly of Fig. l is moved down into the bottom of the hole; and the anchor is then expanded by tamping on the top of the hexagonal bodies 2| of the anchor assembly. As the body 2| of the anchor is forced toward the nut and toward the expander II, the curved bottom portions of the blades slide outward over the corner 39 and are directed into the surrounding undisturbed earth.

Since the blades are quite narrow and narrower than the blades of the prior art devices, they penetrate the undisturbed earth more easily. The expanding is continued until the inside of the expanding body has struck the top portion M of the expander '14. This impact can be definitely heard and felt with a tamper; and therefore the user knows that he has expanded this anchor completely.

The present blades may be made longer than anchors of the same size of the prior art, for the same size hole; and therefore they penetrate farther into the undisturbed earth. Their holdi-ng power is augmented by the fact that they extend radially over a greater distance into the earth.

The advantages of the present anchor over those of the prior art are as follows:

'1. The present anchor utilizes a minimum amount of steel to produce an equal expanded area.

2. The narrow blade stock is easily handled in production.

3. The assembly is made of three identical blades, and involves 'a minimum amount of die work.

4. Greater holding power results from this anchor because the expanded area is composed of six narrow arms, which penetrate deeper into the undisturbed earth.

5. Part of the holding power is due to the resistance to the shearing of the blades through the earth; and this anchor has a greater holding power because of its greater perimeter when expanded.

'6. The greatest economy of material is obtained by this anchor because the major portion of the blades is in the undisturbed earth, whereas other anchors have .forty to seventy percent of the blade area covering the base .or expander, with one or two thicknesses, having only thirty to sixty percent of the blades in the undisturbed earth.

While I have illustrated a preferred embodiment of my invention, .many modifications may be .made without departing from the spirit of the invention, and I do not wish to be limited to the ,precise details or construction set forth, butdesire to avail myself of all changes within the soqpelof the appendedelaims,

Having thus described my invention, what I claim as new and desire to secure by Letter:, :Raltent of the United :States, is:

1. An expanding earth anchor nomprising an expander member or sheet metal provided with a circular border and with an upwardly curved camming surface surrounding a central bore for receiving a guy rod, and a roughly conical :blade assembly comprising three blade units forrhed of substantially rectangular elongated strips of sheet steel, each blade un it having a central aperture for the guy rod and the blade units extending at angles of degrees to each other, the said blade units being cut away on each side adjacent the central aperture with four triangular cut-outs, leaving a substantially hexagonal tamp-,

ing area surrounding said aperture and providing each blade unit with narrowed bending portions on the opposite sides of said tamping area, the blade units being bent downward at an obtuse angle at said bending portion to bring the blade units into the said roughly conical form with the inner surfaces of the ends of the blades engaging said expanding member.

2. An expanding earth anchor comprising an expander member of sheet metal provided with a circular border and with an upwardly curved camming surface surrounding a central bore for receiving a guy rod, and a roughly conical blade assembly comprising three blade units formed of substantially rectangular elongated strips of sheet steel, each blade unit having a central aperture for the guy rod and the blade units extending at angles of 120 degrees to each other, the said blade units being cut away on each side adjacent the central aperture with four triangular cut-outs, leaving a substantially hexagonal tamping area surrounding said aperture and providing each blade unit with narrowed bending portions on the opposite sides of said tamping area, the blade units being bent downward at an obtuse angle at said bending portion to bring the blade units into the said roughly conical form with the inner surfaces of the ends of the blades engaging said expanding member, each of the blades of said blade units being curved outwardly concave in a longitudinal direction and formed with a longitudinal long oval bulge forming a stiffening portion of the blade.

3. An expanding earth anchor comprising an expander member of sheet metal provided with a circular border and with an upwardly curved camming surface surrounding a central bore for receiving a guy rod, and a roughly conical blade assembly comprising three blade units formed of substantially rectangular elongated strips of sheet steel, each blade unit having a central aperture for the guy rod and the blade units extending at angles of 120 degrees to each other, the said blade units being cut away on each side adjacent the central aperture with four triangular cut-outs, leaving a substantially hexagonal tamping area surrounding said aperture and providing each blade unit with narrowed bending portions on the opposite sides of said tamping area, the blade units being bent downward at an obtuse angle at said bending portion to bring the blade units into the said roughly conical form with the inner surfaces of the ends of the blades engaging said expanding member, each of the blades of said blade units being curved outwardly concave in a longitudinal direction and formed with a longitudinal long oval bulge forming a stiffening portion of the blade, the said blades having the corners of the blades on each side adjacent said triangular cut-outs bent outwardly to permit the blades to be bent downwardly into closer abutting relation, reducing the size of the anchor and the size of the hole required for its placement.

WILLIAM L. HOLLANDER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 831,464 OLeary Sept. 18, 1906 1,629,353 Michalicek May 17, 1927 1,702,536 Cole Feb. 19, 1929 1,724,341 Cole Aug. 13, 1929 1,973,995 Pieper Sept. 18, 1934 2,570,646 Cole Oct. 9, 1951 v FOREIGN PATENTS Number Country Date 242,834 Great Britain Nov. 19, 1925