US3128666A

US3128666A - Split bolt anchor

Info

Publication number: US3128666A
Application number: US44498A
Authority: US
Inventors: Robert S Baker
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-07-21
Filing date: 1960-07-21
Publication date: 1964-04-14
Anticipated expiration: 1981-04-14

Description

April 14, 1964 R. s. BAKER SPLIT BOLT ANCHOR '2 Sheets-Sheet 1 Filed July 21, 1960 INVENTOR zPaiefii 61 30 1691 ATTORNEYS April 14, 1964 R. s. BAKER SPLIT BOLT ANCHOR Filed July 21, 1960 2 Sheets-Sheet 2 BY W United States Patent Ofilice 3,128,666 Patented Apr. 14, 1964 3,128,666 SPLIT BOLT ANCHOR Robert S. Baker, Tampa, Fla., assignor to Julian L. Cone, J12, Charles W. Cone, and Douglas P. Cone, all of Tampa, Fla.

Filed July 21, 1960, Ser. No. 44,498 1 Claim. (Cl. 85-2.4)

This invention relates to anchors, and particularly to anchors which are split and, when inserted into an opening, may be expanded and brought into wedging engagement with the sides of the opening in which they are placed.

While the anchor of the present invention is suitable for use in any place where a split anchor is needed, it has special features adapting it to use in fastening rails to concrete crossties. In co-pending application Serial Number 30,615 filed May 20, 1960, and now abandoned, there is disclosed a method and means for anchoring in a stressed concrete member. As pointed out in that application, concrete has little tensile strength, and drawing up upon a wedge nut ina tapered hole in a concrete element will cause the concrete to crack and split. If, however, this type of fastening is used in a stressed concrete member, and the wedging force is exerted in the region, and in the direction, of the stressing cables, the wedging action will be opposed by the stressing cables and there will be no cracking or splitting of the concrete. It is for use in such connection, where the wedging force is to be exerted in one plane only, that the present invention is particularly adapted.

The general object of the present invention is to provide a split wedge nut, or anchor, which can be inserted into an opening and will be held against withdrawal when a bolt is threaded in it.

A more specific object of the invention is to provide a split anchor which has mating sections which may be relatively offset to reduce the overall width of the anchor for insertion into a hole.

Another object is the provision of such an anchor wherein the mating sections are disconnected, yet the sections will move into proper alignment when seated in an opening.

A further object is to provide an anchor having similar mating sections which can be manufactured quite inexpensively, but which will have a positive holding action.

Other objects of the invention will appear from the following description of one practical embodiment thereof, when taken in conjunction wtih the drawings which accompany, and form part of, this specification.

In the drawings:

FIGURE 1 is a perspective view of a wedge anchor made in accordance with the present invention;

FIGURE 2 is a side elevation of the anchor;

FIGURE 3 is a back view of one of the mating members making up the anchor;

FIGURE 4 is a top plan view of the anchor;

FIGURE 5 shows the mating members offset longitudinally relative to one another and being inserted in an opening in a member for anchoring therein;

FIGURE 6 is a view of the anchor in place in the member and in anchoring position;

FIGURE 7 is a horizontal section taken on the line 77 of FIGURE 6; and

FIGURE 8 is a horizontal section taken on the line 8-8 of FIGURE 6.

In general, the invention consists of an anchor composed of a pair of disconnected mating members which can be positioned offset longitudinally relative to one another to produce a unit having an overall width small enough to allow insertion into the small end of a tapered hole, and which will automatically align themselves in the hole to receive a bolt and assume an overall shape which will prevent withdrawal from the tapered hole.

Referring to the drawings in detail, the anchor 1 is shown as consisting of two

mating members

2 and 3. These two members are substantially identical, and could be duplicates; therefore, only one will be described in detail. The reference numerals, however, are applied to like parts of each member.

Each mating member of the anchor includes two longitudinally spaced

cylindrical sectors

4 and 5 of relatively short lengths. The sector 5 is at the end of the member which is inserted first into a hole in which it is to be sent and, therefore, farthest removed from the hole entrance when in use. The other sector 4 is near the opposite end of the member. Both sectors have the centerlines of their inner, concave surfaces tangent to the longitudinal plane of the member (represented by the line xy, FIGURE 2). The sectors, in cross-section, are of less than semi-circular extent and, as indicated above, are symmetrically disposed about the plane xy. The sector 5 has internal screw threads 6.

The main body of the member extends flat and in the plane xy on both sides of the sector 4 to form co-planar

flat sections

7 and 8. The body terminates at the top in a locating flange 9 which extends from the sector 7 at right angles to the plane xy, and projects in the opposite direction to the curved sectors relative to that plane.

From the end of the flat section 8, the body member diverges from the reference plane toward the sector 4, to provide an inclined leg which forms the wedge of the anchor. Similarly, the body member diverges from the plane from the sector 5 toward the sector 4, supplying a brace 11 between the sector 5 and the adjacent end of the leg 10. A foot 12 projects from the bottom of the sector 5, parallel to the locating flange 9, and extends in the same direction as the locating flange.

As mentioned above, the two members of the anchor may be identical. They may, however, be made in matched pairs, to insure matching of the threads in the sectors 4, or for other reasons, and the locating flanges may be beveled on opposite sides, as at 13 to indicate rights and lefts.

A pair of the members making up the anchor are adapted to be inserted in a hole in a unit of some kind, for example a railroad crosstie, to become wedged therein. Such a crosstie 14 is shown, and the hole in which the anchor is to be seated is indicated at 15. The hole is of non-round cross-section, preferably rectangular, and includes an upper section 16, a central section 17 and a lower section 18. Two opposed walls 19 of the hole are parallel for the full depth of the hole. The other walls 2!) are parallel in the upper section of the hole, diverge downwardly in the central section and are again parallel in the lower section. The tapering walls of the central section form the wedging surfaces, and if the unit in which the hole is located is of stressed concrete, the flare will be in the direction of the longitudinal extent of the stressing cables. The structural unit 14 has a pair of recessed seats 21 in its upper surface extending in oppo site directions from the walls 20 of the hole. These not only indicate the entrance position of the anchor, but cooperate with the locating flanges of the anchor to insure proper seating of the anchor members in the hole.

When the anchor is to be put into the hole, the two members are arranged face-to-face but longitudinally staggered as shown in FIGURE 5. By this arrangement, sectors 4 are out of horizontal alignment and the arcuate wings 22 of one member may rest upon the flat section 7 of the other, while the wings 22 of the second abut the flat section 8 of the first. At the same time, the sector 5 of the first-mentioned member will fit within the dog-leg angle formed by the inclined leg 10 and the brace 11 of the second. This will materially reduce the combined width of the anchor and permit insertion of the assembled members into and through the narrow upper section 16 of the hole. As the anchor moves downwardly, the locating flange 9 of the lowermost member will drop into its seat 21, stopping further downward movement of that member. At this time, the lowermost member will have its inclined leg 10 within the central section of the hole and the sector 5 and foot 12 will be in the lower section of the hole. As the uppermost member continues its downward movement, its sector 5 will move down the incline of brace 11 of the other member, spreading the two members and moving them outwardly toward the sides of the hole. The downward movement of the second member will stop when the locating flange 9 falls into its seat 21. Seats 21 are sufficiently deep so that the locating flanges of the anchor members will not project above the top of the crosstie.

After the anchor members are in place, whatever members are to be attached are positioned and a bolt 23 is inserted. The bolt will enter between the flat surfaces 7 of the anchor members and between the arcuate sectors 4. This will complete the separation of the members, and the wings 22 of the arcuate sectors 4 will embrace the bolt shank to tie the bolt and anchor upper sections against lateral separation. The bolt will be moved down until it engages the threads of the sectors 5. The feet 12 will be in engagement with the walls of the brace section of the hole to hold the sectors 5 to proper spacing, so that they cannot spread to release the bolt. As the bolt is tightened, the anchor will be drawn upwardly bringing the inclined legs 10 into tight wedging engagement with the tapered walls of the central section of the hole. The \vedging engagement will be complete and positive along the full lengths of the inclined legs 10 as the

flat sections

7 and 8 and the sectors 4 will be in contact with the bolt shank and prevent inward movement of the upper ends of the anchor members, and the braces 11 form struts between the sectors 5 and the lower ends of the legs 10. The bolt can be tightened to considerable degrees, and the anchor will increase its holding eifect with increased tightening.

While one practical embodiment of the invention has been disclosed, the structural details shown and described are merely for purposes of illustration, and the invention may take other forms Within the scope of the appended claim.

What is claimed is:

An anchor for insertion into an opening having oppo site walls which converge toward one end of the opening for wedging engagement with the converging Walls upon the insertion of a threaded bolt into the anchor, the anchor comprising a pair of unattached elongated mating members adapted to lie within said opening in a confronting face-to-face relationship, each member having an arcuately concave threaded sector adjacent one end for engagement with the threads of the bolt when said members are in said face-to-face relationship, a sector having a smooth internal surface and arcuate wings to embrace the bolt on each member adjacent the end opposite the arcuately concave threaded sector, the arcuately concave threaded sectors and sectors having arcuate wings of the respective members lying in substantially the same longitudinal planes of their respective members, legs integrally connected to and extending from said sectors having arcuate wings, said legs inclined to the respective longitudinal planes of the sectors of the two members with the legs inclining in opposite directions away from said planes when the mating members are in face-to-face relation, said legs being flat and of substantially uniform thickness whereby the planer inner and outer surfaces thereof are substantially parallel and braces connecting one end of each leg with one of the threaded sectors of its respective member, said braces being inclined relative to said respective longitudinal planes, said braces being fiat and of substantially uniform thickness whereby the planer inner and outer surfaces thereof are substantially parallel, the inclinations of said leg and brace of each member meeting to define an apex thereby creating an offset relative to the said plane of the respective members so that when the members are staggered longitudinally relative to one another the arcuately concave threaded sector of one member of the pair will nest within the offset of the other member of the pair to reduce the span of the members across the inclined legs to permit simultaneous insertion of a pair of said members into the small end of the opening when staggered relatively longitudinally from their confronting relationship.

References Cited in the tile of this patent UNITED STATES PATENTS 1,032,106 Belton July 9, 1912 1,111,657 Kohler Sept. 22, 1914 1,349,998 Aylward Aug. 17, 1920 1,920,141 Fischer July 25, 1933 2,373,482 Lev Apr. 10, 1945 2,771,746 Fischer et a1 Nov. 27, 1956 FOREIGN PATENTS 459,994 Germany May 18, 1928