US 3456547 A
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Jul 22, mm G. H. STRONG 3,456,547
ANCHORING MEANS Filed Oct. 2, 1967 2 Sheets-Sheet 1 INVENTOR.
BGYARONER HSTRONG AT RNEVS July 22, 1969 G. H. STRONG 3,456,547
ANCHORING MEANS Filed Oct. 2, 1967 2 Sheets-Sheet 2 INVENTOR.
gamma-n2 H. STRONG TTORNEVS United States Patent 3,456,547 ANCHORING MEANS Gardner H. Strong, 22 Olive Ave., Piedmont, Calif. 94611 Filed Oct. 2, 1967, Ser. No. 672,327 Int. Cl. F16b 35/02, 13/10; B66f 11/00 US. Cl. 851 6 Claims ABSTRACT OF THE DISCLOSURE An anchoring means for removably securing a lifting ring used in lifting heavy members, as for example, concrete slabs. The anchoring means consists of a first member to be embedded in the slab and a second member that removably engages the first member to secure the lifting ring to the slab. The second member is designed for rapid engagement with the first member to reduce the time required to attach and remove the lifting ring.
Background of the invention The present invention relates to an anchoring means for securing together two members. For example, it can be used for securing a removable lifting ring to a heavy object to permit the attachment to the object of a hoisting means for lifting the object.
In recent years a form of building construction referred to as the tilt-up slab method has come into rather wide usage. In a tilt-up slab building, large concrete slabs are formed either on the floor of the building or on a level ground surface. The concrete slabs are then lifted to a vertical position and interconnected to form the walls of the building.
The means used for lifting the slabs must be removable after the slabs have been lifted into place to present a smooth surface on the walls of the building. Since the lifting attachments must be installed and removed, they must be easily and rapidly installed to save time in erecting slab walls of the building.
The present practice is to embed a nut member in the concrete slab and then attach a lifting eye to the slab by passing a bolt through the eye and threading it into the nut member. While this means provides a satisfactory anchoring for the lifting eye, it requires that the bolt be threaded into the nut means. Since the nut means is embedded in the concrete when the slab is originally poured, small particles of concrete may be deposited on the thread surfaces of the bolt means. The presence of the concrete on the thread surfaces requires the use of a wrench to thread the bolt into the nut. This requires considerable time and thus increases the time required to erect the walls. Additional time is required to remove the bolt, since a wrench must be used to remove the bolt.
Summary of the invention The present invention solves the above problems by providing a bolt means which may be rapidly inserted in a nut means and requires only a partial revolution to securely lock the bolt in place. More particularly, the bolt means is formed from a pair of separate longitudinal cylindrical segments such as is formed when a conventional bolt is split along its longitudinal axis to form two bolt halves. A portion of the bolt along the longitudinal axis is removed so that when the two segments are placed together, they may be easily inserted into the nut means. After the two bolt segments are inserted in the nut, a key member is positioned between them to expand or separate the two bolt segments into engagement with the female threads of the nut means. A partial turn of the bolt will then lock it securely in place. To remove "ice the bolt, the key is first withdrawn and the two segments of the bolt brought together to-disengage their threaded surfaces from the nut threaded surfaces and permit withdrawal of the bolt segments.
It is desirable in certain cases to provide longitudinal lands along the surface of the key and cooperating grooves along the inner surfaces of the bolt segments. These prevent undesirable rotation of the key between the segments as well as provide a means by which the key will be guided longitudinally alongthe bolt. Likewise, when additional security is desired, alocking pin can be installed in, a hole formed in the head of the two segments of the bolt to retain the key in position. An alternat e arrangement is to provide a longitudinal slot in the key and a pin through the slot to retain and guide the key.
Brief description of the drawings The above objects and advantages of this invention will be more easily understood from the following detailed description of a preferred embodiment when taken in conjunction with the attached drawings in which:
FIGURE 1 is a perspective of a lifting device incorporating a preferred embodiment of an anchoring means of this invention;
FIGURE 2 is an exploded perspective view of the lifting device showing the individual parts;
FIGURE 3 is a vertical section of the lifting device taken along a plane indicated by line 3-3 in FIGURE 1;
FIGURE 4 is a top view of the bolt means shown in FIGURES 1-3;
FIGURE 5 is a perspective view of a modified bolt means; and
FIGURE 6 is an exploded perspective view of the modified bolt means.
Description of a preferred embodiment Referring now to the drawings, an anchoring means constructed according to this invention is shown for use in providing quick connection and disconnection of a lifting device to an object to be lifted. More particularly, the anchoring means in the embodiment shown consists of a nut member 10 embedded in a concrete slab to be lifted and a second member or bolt 11 that is used to secure the lifting ring 12 to the slab. The construction of the nut member 10 is best illustrated in FIGURE 2 and consists of a nut 13 that may be formed by a plurality of closely spaced turns of heavy wire or rod. A plurality of arm members 14-17 are secured to the outer surface of the nut 13. Each of the arm members consists of a vertical section 20 that is secured to the outer surface of the nut by suitable means, as for example, welding or the like. The vertical portion 20 of each of the arms is JOlIled to an irregularly shaped portion 21 that extends in a generally horizontal direction from the vertical portion 20. The horizontally extending portion 21 of each arm may take various shapes providing there are suflic1ent 1rregularities to securely anchor the nut member in the slab.
The nut member is embedded in the slab 22 to be lifted by disposing the nut member therein when the slab is cast. For example, the nut member may be positioned in the desired location and the center of the nut 13 plugged with a suitable material to exclude the concrete therefrom. The concrete can then be poured, the slab finished, and the plugging material removed. Suitable plugging materials may consist of wooden plugs or expanded styrene foam.
The lifting ring may take various forms, for example hinged rings or eyes, or specialized attachments that are designed to cooperate with a particular type of hoisting means. As illustrated in the drawings, and particularly in FIGURE 2, the lifting ring consists of a'flat rectangularshaped base plate to which is attached a central boss member 31. The boss member 31 is provided with a central opening 37 having substantially the same diameter as the overall diameter of the bolt means. The boss member may be formed integrally with the base plate as by means of casting or may be formed separately and attached to the base plate by means of welding and the like. The boss 31 is provided with two outwardly extending horizontal pin members 32 and 33.
A lifting ring or eye 34, provided with bosses 38, 39 at its lower end, is pivotally mounted on the pins 32 and 33. The lifting ring or eye 34 may be held in position be peening over the ends 35 and 36 of the pins 32 and 33. While the pins 32 and 33 are shown as being formed integrally with the boss member 31, it may be preferable to form the pins separately, then attach the lifting ring 34 to the boss by driving the ends of the pins into holes bored I in the boss member. When a unitary structure is used for the boss and pins, it will be necessary to open the ring 34 so that the ends of the ring can be placed over the pins. The ring can then be closed to its original position.
The construction of the second member or the bolt 11 is best illustrated in FIGURES 2 and 3. The bolt member 11 consists of two substantially identical segments 40 and 41 that may be individually formed or may be formed by longitudinally splitting a bolt and removing a portion of it. The main requirement of the two bolt segments 40 and 41 is that when their opposing inner faces are in contact, their overall diameter is slightly less than the minor diameter of the threads in the nut 13. In addition, the edges 42 and 43 of the two segments are relieved so that the diameter across the fiat surface of the nut members is also slightly less than the minor diameter of the threads of the nut 13. When the two bolt segments are formed as described above, it is possible to insert the two segments into the nut member, since the overall diameter of the two segments will be less than the minor diameter of the threads of the nut 13.
The two segments of the bolt are expanded by means of a key 45 into position in which the bolt locking elements in the form of threads engage the locking elements (threads) of the nut member. The key 45 is a flat plate member having an outline that corresponds substantially to the outline of the flat surface of the segments. The key is also provided with a head portion 46 which corresponds substantially to the dimensions of the hexagonal head of the segments. As shown, tabs or ears 47 project outwardly from the edges of the head portion 46 to provide means by which the key may be gripped for lifting from between the segments. To insure that the key travels longitudinally along the segments, lands 52 and 53 may be formed on opposite sides of the key as shown in FIGURE 4. The lands extend longitudinally along the outer surface of the key and engage similar grooves 54 and 55 formed in the flat surface 56 of the bolt segments. The use of a hammer or similar tool may be necessary to drive the key between the segments when concrete has been deposited on the threads of the nut 13.
An additional safety factor can be obtained by providing a horizontal pin hole across the hexagonal head of the bolt means and a similar hole 51 in the head of the key means. Thus, a safety pin may be driven into the aligned holes to retain the key in position and prevent its accidentally falling out.
Operation The above anchoring means is operated by first embedding the first or nut member in the object to be lifted. As explained in the case of a concrete slab, the nut member may be positioned and the concrete poured around the member to firmly embed it in position. The lifting ring 12 is then secured to the slab by placing it over the nut member and inserting the two segments of the second member or bolt through the hole in the lifting ring and into the nut member. The two segments of the bolt member are expanded so that their male thread surfaces engage the female threads of the nut means by the means of the key 45. The key 45 is driven between the two segments to expand them outwardly into engagement with the threads of the nut member. As explained, the key may be retained in position by inserting a safety pin through the aligned holes in the head of the bolt and key member. After the two segments of the bolt member have been expanded into position by the key, the bolt may be tightened by applying a wrench and turning the bolt slightly. Less than a single turn will be required to completely tighten the bolt in the nut means to securely fasten the lifting ring to the object to be lifted. The object may then be lifted by inserting the hoisting hook 60 in the lifting ring 45 and lifting it in the conventional manner.
Referring to FIGURES 5 and 6, there is shown a modified bolt means in which a pin serves to fasten together the key and the bolt segments. The two bolt segments 60 and 61 have substantially the same configuration as the bolt segments shown in FIGURES 1-3. The key 62 is modified in that it is provided with a longitudinal slot 63 that extends close to the bottom 64 of the key. A pin 65 extends through the heads of the two bolt segments and the slot 63. The pin should be a loose fit in both the slot and the heads of the bolt halves and may be retained in place by peening over the ends of the pin.
The heads of the bolt segments are provided with rectangular-shaped recesses 66 and 67 that receive the end of the key when it is withdrawn. When the modified bolt means is used, the key is completely withdrawn and the segments moved toward one another with the end of the key fitting in the recesses. The bolt means may then be inserted in the nut means and the key driven between the two bolt segments to expanded them. The bolt can then be tightened by using a wrench. The modified bolt can be removed by first withdrawing the key and then moving the bolt segments together. The bolt can then be withdrawn from the nut means.
It will be appreciated that with the above described arrangement, the key and bolt segments are held together before and after the bolt is positioned within a nut, and yet the key may be moved longitudinally of the segments to permit collapsing together of the latter.
While the anchoring means has been described in relation to the particular nut means and threaded configuration, obviously other nut means and thread types may also be used. The main feature of the present invention is the use of a split bolt means that permits the bolt to be rapidly inserted in the nut means and then expanded so that its threads will engage the thread surfaces of the nut means. This reduces the required rotation of the bolt to less than a complete turn, thus reducing the time required to secure the lifting ring to the slab and remove it after the slab is lifted into position. Furthermore, although the anchoring means of the invention has been found particularly useful in the securance of a lifting ring to a concrete slab, it is not limited to such use. It can be advantageously employed whenever a rapid and yet sturdy securance is desired. In this connection, the anchoring means has been found to be particularly effective in securing concrete panels together or to a building frame.
What is claimed is:
1. An anchoring means for rapidly securing two members together comprising a nut member having an internal screw thread, a bolt formed of a pair of separate longitudinal semi-cylindrical segments each of which has an inner side which when placed together with the inner side of the other segment provides the segments with an exterior transverse peripheral dimension less than the interior transverse peripheral dimension of said nut member whereby said bolt can be translatably inserted into said nut member, the exterior side of each of said segments having thread portions interengageable with and complementary to the screw thread on the interior surface of said nut member, and a key member insertable between said inner sides of said segments to space said segments from each other and maintain said segment thread portions in engagement with said thread of said nut member so that said segments and said key member may be rotated as a unit with respect to said nut member to tightly draw the unit axially further into said nut member, said key member having a transverse dimension less than the interior diameter of said nut member whereby said key member is freely insertable between the inner sides of said segments interiorly of said nut member.
2. The anchoring means of claim 1, wherein said nut member is adapted to be embedded in an object.
3. The anchoring means of claim 2 wherein said nut member is formed of a plurality of closely spaced turns of heavy wire and includes a plurality of leg members extending therefrom for firmly holding the same embedded within an object.
4. The anchoring means of claim 1 wherein said segments and said key member include cooperating longitudinal lands and grooves for longitudinal guidance of said key member between said segments.
5. The anchoring means of claim 1 wherein said pair of segments and said key member have pin receiving holes therethrough adapted to be aligned upon positioning of said key member between said segments.
6. An anchoring means for rapidly securing two members together comprising a nut means, a bolt formed of a pair of separate longitudinal cylindrical segments which when placed together have an exterior peripheral dimension less than the interior peripheral dimension of said nut means whereby said bolt can be translatably inserted into said nut, a key member insertable between said segments to separate said segments and maintain them in engagement with said nut means; said key member being .provided with a longitudinal slot extending substantially to its ends, each of said bolt segments including a head portion, a pin extending transversely through said head portion and securing said bolt segments together for limited movement toward and away from one another, said key member being disposed between said segments with said pin extending through said slot to permit longitudinal movement of said key member relative to said segments, and recesses being formed in the inner surface of each segment about said pin adapted to receive the end of said key when said key is in the withdrawn position to permit said segments to be placed together.
References Cited UNITED STATES PATENTS 1,087,759 2/1914 Gould l5 2,563,164 8/1951 Fletcher 294-89 3,216,171 11/1965 Jenkins 8532 ANDRES H. NEILSEN, Primary Examiner US. Cl. X.R. 294102