a) Field of the Invention
This invention relates generally to the field of concrete form construction, and more particularly to the tie-rod assemblies which position the two form wall sections at the proper spacing distance from on another.
b) Background Art
A common method of constructing concrete walls is to form two wall form sections which have inner forming surfaces facing each other and spaced from each other by a distance equal to the thickness of the wall to be formed. Commonly, each of these walls is made of panels (e.g. 4′×8′ plywood panels), with each set of panels being placed in a common plane. To maintain the panels properly spaced with respect to one another, there is commonly provided a bracing/positioning structure in the form of sets of horizontally extending walers and vertically aligned strongbacks which bear against the outside surface of the panels. Through openings are drilled through the walers and through the panels, and tie-rods extend through matching pairs of aligned openings formed in the two wall form sections. Then retaining members are connected to each outer end of the tie-rod, such as a wing nut or other nut which is threaded onto the end of the tie-rod to press against a metal bearing plate that in turn bears against the outside surface of one of the walers.
With the two wall form sections being properly positioned and spaced from one another, and with the tie assemblies (i.e. the tie-rods and the retaining devices) properly in place, then the pour of the concrete can proceed. Quite commonly, there are metal reinforcing rods and/or other reinforcing members positioned in the receiving area of the concrete to form the concrete wall or other concrete structure in the form of reinforced concrete. After the concrete has cured sufficiently, either or both of the retaining members are removed from each tie-rod, the tie-rods removed, and the two wall form sections are taken down and are generally at least partially disassembled in some manner.
Obviously, if the tie-rod is to be removed from the hardened concrete, provisions must be made to avoid the central portion of the tie-rod that is in the region of the concrete pour from becoming embedded in the concrete. Accordingly, there have been various attempts in the prior art to address this problem.
Further, in addition to the problem of removing the tie-rods, there have also been various arrangements to properly space the surfaces of the two form wall sections from one another. In other instances, such spacing devices are not used, and the force of the concrete in the receiving area bearing against the inside forming surfaces of the form wall sections (being held in place by the tie-rods) is depended upon to ensure the uniform thickness of the wall.
Two of the patents which are of interest are U.S. Pat. No. 4,044,986 (Strickland et al.) and U.S. Pat. No. 4,159,097 (Strickland). Both of these patents will be discussed later in this text after the brief description of the drawings, and in this section on background art, they will be discussed only briefly.
The earlier of these two patents (i.e. U.S. Pat. No. 4,044,986) relates primarily to various devices to anchor the tie-rods (in U.S. Pat. No. 4,044,986 called the “tie”). In FIGS. 20, 21, and 22, there are shown three tie-rod configurations of interest. These are discussed in the text of the patent beginning in column 9, line 42, and continuing on through most of column 10. It is stated that “. . . other forms of tie are equally suitable to practicing this invention. More particularly, solid ties preferably having a continuous taper, such as those illustrated in FIGS. 20, 21, and 22, may also be used to practice this invention. After the concrete structure has set, the continuous taper of these ties permits them to be driven out of engagement with the structure.”
Each of the tie-rods shown in these three figures (FIGS. 20, 21, and 22) appear to be made from a single piece of metal (or at least made as on integral metal piece), and they differ mainly in the configuration of the end retaining sections that connect to a retainer so that the tension can be applied to the tie-rod.
The second patent of interest (U.S. Pat. No. 4,159,097) names Strickland (the first-named co-inventor of the early above-noted patent U.S. Pat. No. 4,044,986) as the sole inventor. In the introductory text of that patent (column 1, beginning on line 13), reference is made to U.S. Pat. No. 4,044,986, and it is stated that one of the features in the apparatus is the use of a tapered tie-rod. It is further stated that such tie-rods are conventionally made from a plurality of steel rods threaded together or cast into a one-piece steel tie that has sufficient strength to hold the form panels together and withstand the stresses imposed upon the ties. The patent goes on to recite the certain deficiencies in that design, and these will be discussed later in the text of this application.
The tie-rod in U.S. Pat. No. 4,159,097 differs from that of the earlier patent (U.S. Pat. No. 4,044,986) in that the tapered portion of the tie-rod is not made of steel and formed as part of the metal piece, but rather is made from a plastic sleeve that is firmly attached to the steel tie-rod. The reasons for this will be discussed later in this text.
A search of the U.S. patent literature has disclosed a number of other patents generally relevant to this technology of providing concrete forms, and each of these are discussed briefly below.
U.S. Pat. No. 5,282,603 (Taraldsson) relates to a clamping device to be used in concrete forms. In FIG. 1, there is shown a sealing element 7 which comprises two compressible end seals 27 & 28, and a frusto-conical center member 29 having a moderate taper and which is made of a relatively non-compressible material. When the tie-rod is tensioned, the sealing elements 27 & 28 close the two openings 8 & 9 in the forming boards 2.
U.S. Pat. No. 4,726,560 (Dotson) shows a concrete form tie assembly where there is a flexible plastic sleeve 20 which is placed over the tie-rod. There is a cone-shaped member 54 to act as a means of fixedly locating one end of the assembly 10.
U.S. Pat. No. 4,109,893 (Laroche) shows a conical mold panel spacer.
U.S. Pat. No. 3,648,961 (Farrow) discloses a wall tie for concrete forms. There is a tie-rod which extends through a spacer or spreader 32 which has a frusto-conical shape with a moderate taper. The operating position is at a location between the two boards of the concrete forming assembly and keeps the two boards spaced at the proper distance from one another. At one end of the spacer 32, the tie-rod has a threaded end member 44 on which a nut is threaded, and there are two washers 46 & 48 positioned on opposite sides of this threaded member 44. In the assembled position, as we had seen in FIG. 3, this nut 50 with the two washers 46 & 48 properly locates the spacer 32.
U.S. Pat. No. 2,709,292 (Otti) relates primarily to a clamp for concrete forms. There is shown a frusto-conical spacing member 20 having a moderate slant with the larger end bearing against the board member 12 and the opposite end bearing against the other board.
U.S. Pat. No. 2,502,672 (Royther) discloses a tie-rod having a spreader or spacing member 6 which has threaded sockets on opposite sides. The tie-rod comprises two threaded members which are threaded into the end holes 8 & 9. The purpose of this is that when the concrete is being set, these function as a spacer. However, the spacers do not need to be removed until the concrete has hardened, this being due to the fact that the nuts can be unthreaded from the ends of the tie-rod while the spacer remains in place. After that, then the spacer can be removed.
U.S. Pat. No. 1,436,345 (Jackson) shows a tie-bar and a spacer. The spacer 13 is a frusto-conical member with a moderate taper and it is positioned between two opposing forming walls. In FIG. 10, the spacer is shown being used to form a double-wall container or other member.
The present invention provides a tie-rod assembly and a method of using the same in providing tie-rod connections between two sections of a wall-forming structure, with the wall-sections being spaced from one another to define a concrete receiving region.
There is a plurality of tie-rod assemblies which extend between the two opposite wall-forming sections, and through the concrete receiving region.
Each of the tie-rod assemblies comprises an elongate cylindrically shaped tie-rod having exterior threads along at least a portion of an outer cylindrical surface of the tie-rod. There is a sleeve section which is arranged to be moveably mounted on the tie-rod section. This sleeve section comprises first a tapered sleeve member having a forward end and a rear end and defining a through passageway to receive the tie-rod. The tapered sleeve member has an outer tapered surface with a small diameter forward circumferential edge sized to fit closely to the exterior surface of the tie-rod, and having a larger diameter rear end spaced regularly outwardly from the tie-rod.
Also, the sleeve section comprises a positioning member connected to the larger diameter portion of the tapered sleeve member. This positioning member has an interiorally threaded opening to receive the tie-rod and to threadedly engage the exterior threads of the tie-rod.
The tie-rod and the sleeve section are arranged so that with the sleeve section positioned with the tie-rod extending therethrough, the sleeve section can be rotated, and with the threaded positioning member engaging the threads of the tie-rod, to move the sleeve section to a desired location along the tie-rod.
The tapered sleeve member is configured and has the connection to the tie-rod which is such that after the concrete wall is formed, the tie-rod assembly can be removed by impacting the front end of the tie-rod and causing the tie-rod assembly to be moved out of the concrete wall formed in the forming region.
In a preferred form, the tapered sleeve member has its through passageway configured so as to expand in a direction from the forward end of the rear end of the sleeve member. Desirably this is accomplished by providing the tapered sleeve member in the form of a closed metal sheet having the configuration of a truncated cone.
Also, in a preferred form, there is provided a lock nut which threadedly engages the tie-rod and is able to be rotated into engagement with the positioning member to retain a positioning member at a desired location on the tie-rod.
In the method of the present invention, the tie-rod connections are provided for a forming structure for concrete walls having first and second forming sections on opposite side of the forming region where the concrete wall is to be made.
The method comprises first providing the tie-rods as described above and further providing the sleeve section as provided above, mounting the sleeve section onto the tie-rod and adjusting the position of the sleeve section. This is done so that end portions of the tie-rod that extend beyond the forward and rear ends of the sleeve section are sufficiently long so that the end portions of the tie-rods are able to extend through the forming sections to connecting locations, and so that the sleeve section is positioned in the forming region.
Then retaining devices are applied to opposite ends of the tie-rods to position the forming structures at the proper location for forming the concrete wall, after which the concrete wall is poured and is permitted to cure.
After the curing, force is applied to the first ends of the tie-rod assemblies to drive the tie-rod loose from the concrete wall structure and removing the tie-rod assemblies from the wall structure.
As an alternative embodiment, the elongate tie-rod is provided, either with or without the exterior threads. The sleeve section is also provided having the tapered sleeve member and also the positioning member. The positioning member has the opening to receive the tie-rod member, and there is a fastening device to engage the exterior surface of the tie-rod.
As a further alternative embodiment, the positioning member could be formed with partial threads, which for example, would be diametrically opposed, each having an arcuate length of less than 90 degrees. Then there could be similar opposing partial threads formed on the tie-rod. In this way the positioning member could be rotated to a desired position where the threaded portions are not in engagement, and the sleeve section can be moved along the length of the tie-rod and then rotated 90 degrees into locking engagement relative to movement along the tie-rod.
Also as a further modification, the positioning member can be formed as part of the sleeve, by crimping or forming the large diameter end portion of the sleeve, possibly utilizing additional metal material, to form the threads in the interior surface of the positioning member against the tie-rod or some other forming device and also have these formed as what is equivalent to an integral structure of the positioning member and the sleeve. Alternatively, the thread on the tie-rod could have at least one set of threads with a circumferential gap and the positioning member having a partial thread or threads capable of passing through said gap.
Other features of the present invention will become apparent from the following detailed description.
a) Discussion of Prior Art Patents U.S. Pat. No. 4,044,986 and U.S. Pat. No. 4,159,097
It is believed that clearer understanding of the construction, functions, and benefits of the present invention will be obtained by first reviewing the two prior art patents that were mentioned initially in the Background of the Invention as being of interest, namely U.S. Pat. No. 4,044,986 and U.S. Pat. No. 4,159,097, with Mr. Strickland being a co-inventor in the first patent and the sole inventor in the second patent. There are shown in
In
As indicated earlier in this text, in U.S. Pat. No. 4,044,986, these three tie-rods are shown primarily for the purpose of indicating different tie-rod configurations that could be used in the invention disclosed in U.S. Pat. No. 4,044,986. Further, each of these appear to be made substantially as a unit without moving parts, and also being entirely metallic structures.
To discuss the prior art further, reference is now made to
In
Abutting against the outside surface 34 of each panel section 28 is a plurality of horizontal positioning/bracing members 36 (commonly called “strongbacks”), and outside of and pressing against the plurality of strongbacks 36 is a plurality of vertically aligned walers 38. These strongbacks 36 and walers 38 are commonly made from wooden posts (e.g. 4″×4″, 6″×6″, or 6″33 4″ posts).
The tie-rod assembly 40 has substantially the same configuration as the tie-rod assembly 10 of the prior art as shown in FIG. 1. However, the materials from which it is made differ, in that the tie-rod is made as two parts of different material which are fixedly joined together. First, there is an elongate cylindrically shaped metal rod 42 that is threaded along its entire length. Then there is a tapered sleeve 44 made from plastic that is injection-molded onto the steel rod. The reasons for doing this are discussed in U.S. Pat. No. 4,159,097 in column 1, lines 26-42 as follows:
In the Summary of the Invention, in column 1, lines 56-63, the rod in the invention of U.S. Pat. No. 4,159,097 is described as follows:
In column 2, line 51 and following, the protective cover is described as extending substantially over the central section of the cylindrical rod, comprising two thirds of the entire length of the rod so that when the steel rod is installed through the concrete structure, the steel rod never comes into contact with the structure. Then in column 3, line 1 and following, it is indicated that the protective cover (i.e., the tapered plastic sleeve) also serves to encase and protect the steel rod itself, thereby inhibiting the formation of rust on the rod in the first place.
In claim 3 of U.S. Pat. No. 4,159,097, in the first part of the third paragraph, and also in claim 7 of the patent, in the first part of the third paragraph, the protective sleeve is claimed as follows:
It can be seen from observing
b) First Embodiment of the Present Invention
This first embodiment of the tie-rod assembly is shown in FIG. 7. The tie-rod assembly 50 of the present invention comprises an elongate cylindrical steel rod 52 having a uniform cylindrical cross-section and an exterior surface 54 which is threaded along its entire length. Such a threaded steel rod is conventional in the prior art, is readily commercially available, and is used in various commercial applications. Then there is a sleeve section 56 which is mounted to the rod 52 in a manner that the sleeve section 56 can be moved to various locations along the length of the rod 52 and held fixedly in such selected location or locations.
This sleeve section 56 comprises a tapered sleeve member 58 that, in this particular embodiment, is shown as comprising a metal wall 60 formed in a frusto-conical shape and having a tapered outer surface 62. In this particular embodiment, the metal wall 60 is conveniently made with a uniform thickness. The tapered sleeve member 58 has a smaller diameter end 64 having an end circular edge 66 and a larger diameter end portion 68.
The sleeve section further comprises an interiorly threaded positioning member 70, which in this particular configuration comprise a positioning nut member 70 which is fixedly connected to the larger diameter end portion 68 of the sleeve member 58. The threads of the nut 70 are configured to match the threads at the surface 54 of the rod 52. There is also provided a lock nut 71 by which the positioning nut may be locked at a specific location on the rod 5. The tapered sleeve member 58 defines an elongated central through opening 72, which in this particular embodiment, increases in diameter from the end portion 64 to the opposite end portion 68. The diameter of the smaller end portion 64 is sized so that it fits closely around the rod 52, but yet permits the sleeve section 56 to be moved along the length of the rod 52.
With reference to
To describe the operation of the present invention, reference is made to
The concrete form structure 82, which is shown in
In this particular embodiment of
To further describe the operation of the present invention, reference is made to the lower part of
The tie-rod assembly 50 is then moved through the pair of aligned openings 94/96 into the position shown in the upper part of
When all of the tie-rod assemblies 50 are properly in place, as shown in the top part of
To loosen the tie-rod assembly from the concrete, the right end of the tie-rod 52 would be tapped with a hammer. After that, the entire tie-rod assembly 50 would be removed from the form structure 82. With the tie-rod assemblies 50 being removed, then the two wall form sections 84 and 86 would be removed from the concrete wall that has been formed. Since this can be done in a manner already accomplished in the prior art, this will not be described in this text.
There are a number of advantages to using the tie-rod assembly 50 of the present invention, and probably the term that would best describe these is the word “versatility”. The metal stock from which the rods 52 can be cut are already available in the prior art, and these can be cut to different lengths to accommodate different applications. For example, if the wall to be formed is relatively thin (e.g. four inches), the tie-rods 52 could be made much shorter. This would be particularly advantageous if there are very small clearances in the construction area. In like manner, the sleeves 56 (which can be made rather inexpensively) could also be made smaller. Even if the wall thickness is small and the length of the sleeves 56 is substantially more than four inches, the relatively longer sleeves could still be used, since these would extend outwardly into the openings in the strongbacks 90 and the walers 88.
Further, there may be a situation where there is very little clearance on one side of the wall being formed, and more clearance on the other side. In that instance, the position of the sleeve 56 on each tie-rod 52 could be adjusted so that the sleeve would be positioned in the concrete receiving area 112, with one end of the rod 52 extending a greater distance out into the open area, and only a very short end portion of the rod being in the area where there is limited access.
This versatility is illustrated in
Then in the middle part of
c) Second Embodiment of the Present Invention
Also, it is to be understood that while the form of the sleeve illustrated in
A second embodiment is shown in
As another alternative, the threaded positioning member can be formed by crimping or forming the large diameter end of the sleeve, possibly in conjunction with other material to form the interim threads and also to form flat circumferential surfaces on the outer surface. Getting therefore, the positioning member can be formed as part of the sleeve by a crimping or forming operation (with or without additional metal material) in the positioning member can be connected to the sleeve by a metal to metal bonding material.
d) Third Embodiment of the Present Invention
Another possible arrangement is shown in
It is to be understood that these two are given by way of example, and it is apparent that there is a variety of other attaching mechanisms which are already available in the prior art, and these are to be included within the broader scope of the present invention.
This application claims priority benefit of U.S. Ser. No. 60/334,759, filed Oct. 17, 2001.
Number | Name | Date | Kind |
---|---|---|---|
1436345 | Jackson | Nov 1922 | A |
2502672 | Royther | Apr 1950 | A |
2709292 | Otti | May 1955 | A |
3648961 | Farrow | Mar 1972 | A |
4044986 | Strickland et al. | Aug 1977 | A |
4109893 | Laroche | Aug 1978 | A |
4159097 | Strickland | Jun 1979 | A |
4726560 | Dotson | Feb 1988 | A |
5282603 | Taraldsson | Feb 1994 | A |
Number | Date | Country |
---|---|---|
147787 | Aug 1950 | AU |
Number | Date | Country | |
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20030071189 A1 | Apr 2003 | US |
Number | Date | Country | |
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60334759 | Oct 2001 | US |