WO2008033121A1

WO2008033121A1 - Rebar positioner for masonry construction

Info

Publication number: WO2008033121A1
Application number: PCT/US2006/035310
Authority: WO
Inventors: Dean Crowell
Original assignee: Dean Crowell
Priority date: 2006-09-11
Filing date: 2006-09-11
Publication date: 2008-03-20

Abstract

A rebar positioner for positioning rebar in concrete masonry units has a spine having a midsection, a first end, and a second end. The first end may be partially offset to form a first rest and the second end may be partially offset to form a second rest. The positioner includes a ring, which may be bifurcatingly attached to the spine. The positioner also includes a crossbar attached to the spine.

Description

REBAR POSITIONER FOR MASONRY CONSTRUCTION

Background Information

[0001]This application claims the benefit of U.S. Provisional Application No. 60/708,650, filed August, 16, 2005.

[0002]In masonry construction, particularly for the construction of retail buildings, such as big box retailers or drug stores, sidewalls are typically made of stacked concrete masonry units (CMUs), commonly called cinder blocks. CMUs are generally rectangular, right parallelepipeds having peripheral sidewalls and a central core. Typically the central core includes two channels extending between the two longer edges of the parallelepiped and separated a medial wall. During construction, CMUs are stacked by offsetting the CMUs of odd and even courses so the various channels of the CMUs align vertically. For example, the left channel of a CMU in one course is positioned over the right channel of a CMU in the course above or below. Such staggering, while increasing stability, also creates relatively continuous vertical channels extending from course to course. Where the blocks are in contact, they are joined by mortar to adhere the blocks together.

[0003]To provide reinforcement, reinforcing bars, commonly called rebar, are extended vertically through the vertical channels, and concrete is poured into the channel and allowed to set. It is common at some construction sites to extend such walls to heights of 30-34 feet. Reaching these heights requires care, however, to insure that rebar properly positions within the channels, and that concrete adequately flows into the channel. In many cases, rebar overlapping may be required to reach desired heights or to build structures of adequate strength. For example, for an 88 inch length of rebar, the upper 40 inches may be overlapped with rebar above, and the lower 40 inches may be overlapped with rebar below, leaving only 8 central inches of rebar without overlapping. Others may use even more overlapping or less overlapping.

[0004] Such proper positioning, centering and overlapping of rebar has typically been accomplished using positioners such as positioner 12 shown in Figure 1. Figure 1 shows a CMU 10 with central channels 11. A z-shaped wire rod 12 includes two lengths 13 j oined by link 15. An oval portion 14 is welded to link 15 in a manner that bisects link 15. In use, z-shaped member 12 is laid on block 10 and mortar is laid onto on surface 18 of block 10. Rebar 16 extends through one half of oval 14 bisected by link 15. The other half of oval 14 can receive a second rebar in order to provide overlapping rebar placement. [0005]Using traditional positioners however, such as, for example, the positioner shown in Figure I₅ creates numerous problems. For example, one of the primary purposes of positioner 12 is to help retain the position of rebar 16. But, because positioner 12 is itself prone to excessive movement relative to block 10, requisite rebar positioning can be difficult. Positioner 12 is prone to lengthwise movement, or movement in line with the longest side of the CMU; widthwise movement, or movement in line with the shortest side of the CMU; and irregular movement, or any diagonal or additional movement. The instability of positioner 12 is further exaggerated during mortar application and the application of additional blocks. And, in some instances, it is necessary to vibrate blocks or walls under construction during mortar or concrete application to facilitate concrete migration into block channels 11. This adds to positioner instability, because such vibration further results in the movement of the rebar positioners. In addition to the general positioning problems that can occur as positioners move generally, another specific problem arises when positioners move widthwise or irregularly. When positioners move widthwise or irregularly they have an increased tendency to punch out mortar on either the exterior or interior portion of the wall. Such problems require extensive and costly repair.

[0006]Others have overcome some of the aforementioned positioning problems using grid-like positioners similar to positioner 22 shown in Figure 2. Positioner 22 has a pair of widthwise arms 24 positioned across the width of the block 10 and a pair of bent arms 26 positioned lengthwise and connected to widthwise arms 24. The positioning of widthwise arms 24 and bent arms 26 creates square 30. Bent arms 26 have a bent portion 32 for contacting the interior part of channel 11 and increasing positioner stability. [0007]While positioner systems such as positioner 22 are desirable for their ability to provide some increased stability, they still leave several problems unaddressed. For example, while bent arms 26 reduce lengthwise movement, they do not always prevent widthwise movement. Again, such widthwise instability, in addition to contributing to general positioning problems also increases the tendency for mortar punch-out. Such positioners are also problematic because square 30 typically allows for too much rebar movement, resulting in further positioning inaccuracies. Even further still, positioners such as positioners similar to positioner 22 do not provide two separate positioner portions for rebar overlapping, which can create additional alignment problems. Various other positioners have various other shortcomings. [0008]Accordingly, an improved rebar positioner is needed.

Summary

[0009]The present invention provides an improved rebar positioner. The rebar positioner includes a spine having a spine midsection, a first spine end, and a second spine end. Preferably the spine includes both an integral first spine rest, located at the first spine end, and an integral second spine rest, located at the second spine end, for resting the positioner on the CMU. Ideally, the first and second rests are offset from the spine midsection and allow the spine midsection to extend into a channel of the CMU. Preferably, the midsection of the spine can be positioned downwardly into the channel with a friction fit, but supports lacking a friction fit are also within the scope of the present invention.

[0010] The rebar positioner also has a ring, preferably attached to the spine near the spine midsection. Preferably, the ring is bifurcatingly attached to the spine, or attached to create two separate ring portions or rebar aligning portions. Those skilled in the art would recognize that attachment can be achieved by any means, such as by welding, clamping or adhesive. Still others may prefer to cast their positioners as a single item, and such forms of construction are considered to be attachments for the purpose of the present invention. Further, while the ring is preferably elliptically shaped to better conform to and position the rebar, the ring can be virtually any shape. For example, in other embodiments the ring may be any number or shape of circles, squares, rectangles, triangles, rhombuses, hexagons, or trapezoids. Still, in other embodiments the ring may have an irregular shape, such as an oval, tear drop, clover, or another shape that is not well defined.

[001 l]The positioner also comprises a crossbar attached to the spine near the spine midsection. The crossbar has a crossbar midsection, a first crossbar end, and a second crossbar end. The crossbar is preferably substantially perpendicular to the spine. In preferred embodiments, the crossbar is also in contact with the ring to increase the strength of attachment, yet embodiments that do not utilize such ring contact are still within the scope of the present invention. Still, in other embodiments, the crossbar may be attached to the spine through the ring, rather than attached directly to the spine, such as, for example, the cross bar contacts the spine without attachment to the spine. In those embodiments where the spine midsection is downwardly positioned in the channel of the CMU, the crossbar, because it is attached near the midsection of the spine, is also downwardly positioned in the channel. The crossbar provides widthwise stability, preferably, by contacting interior walls of the channel. Still in other embodiments, the crossbar may provide widthwise stability by contacting other portions of the CMU, or other portions of the CMU in combination with the interior walls.

[0012]Further, those skilled in the art will recognize that, while in preferred embodiments the ring is attached to the spine, in other embodiments the ring may be attached to the crossbar.

Brief Description of the Drawings

[0013]The invention will be better understood from a reading of the Detailed Description taken together with the Drawings in which:

[0014]Figure 1 shows a prior art positioner on a CMU; [0015]Figure 2 shows another prior art positioner on a CMU;

[0016]Figure 3 shows a positioner according to a preferred embodiment of the present invention;

[0017]Figure 4 shows the positioner of Figure 3 positioned on a CMU;

[0018]Figure 5 shows a side schematic view of one embodiment of the invention installed on several courses of CMU reinforced by rebar; and

[0019]Figures 6-10 show other embodiments of the present invention.

Detailed Description

[0020]Figure 3 shows a rebar positioner 38 according to a preferred embodiment of the present invention. Positioner 38 comprises a spine 40 having a spine midsection 42, a first spine end 44, and a second spine end 45. Positioner 38 includes a first spine rest 46 located at first spine end 44 and a second spine rest 47 located at second spine end 45.

[002I]In the depicted embodiment, both spine rests 46 and 47 are integral with spine 40. While spine 40 could be constructed of numerous materials, e.g. various ceramics, plastics, metals and woods, preferably, spine 40 of the present embodiment is constructed of nine gauge steel wire. Such wire is ideal because it facilitates the shaping of the spine and provides the requisite durability needed for construction. For example, as represented by Figure 3, spine 40 is bent at points 50 and 51 to form the spine rests 46 and 47 and to offset spine rests 46 and 47 from spine 40. While the integral formation of the spine rests 46 and 47 from the spine 40 is ideal in terms of cost efficiency, it is not critical, and others may prefer to construct spines, which contain non-integral spine rests, or, which contain spine rests made of different materials. AU such variations would be within the scope of the present invention.

[0022]Positioner 38 also comprises a ring 60, which attaches to the spine 40 near spine midsection 42. Preferably, ring 60 bifurcatingly attaches to spine 40, or attaches to spine 40 to form a first rebar aligner 62 and a second rebar aligner 64. In preferred embodiments, ring 60 is elliptical. However, the ring of the present invention can be almost any shape, e.g. a circle, square, rectangle, triangle, rhombus, hexagon, trapezoid, oval, or teardrop; or any other shape. Further, while ring 60 of the present embodiment is a continuous ring, discontinuous or broken rings could be used to achieve the present invention. Preferably, the opening of the ring is sized to receive rebar easily, yet inhibit sideways movement.

[0023]Positioner 38 also comprises a crossbar 70, which attaches to spine 40 near spine midsection 42. Crossbar 70 has a crossbar midsection 72, a first crossbar end 74, and a second crossbar end 75. Crossbar 70 attaches to spine 40 substantially perpendicularly to spine 40 and preferably at the approximate crossbar midpoint. Others may prefer other attachment points on crossbar 70, which would still be within the scope of the present invention. In this embodiment, crossbar 70 also attaches to ring 60 for increased structural strength. Such ring contact is not necessary to achieve the present invention, and others using other embodiments may prefer not to attach crossbar 70 to the ring 60. [0024]The positioner 38 is preferably at least partially formed of metal and is more preferably substantially 100% formed of metal. Those of skill in the art would recognize that a positioner may be substantially 100% formed of a metal, even if various attachment means used to construct the positioner are non-metals, such as non-metal adhesives or plastic clips, for example. [0025] A wide variety of metals are ideal for forming the various embodiments of the present invention. For example, positioner 38 could be at least partially to substantially 100% formed of steel metal wires, e.g. six gauge, seven gauge, eight gauge, nine gauge, ten gauge or eleven gauge wires. Preferably, the positioner is formed of nine gauge steel wire. In preferred embodiments, the positioner is at least partially coated with a rustproof coating, such as a galvanized coating, or has at least partially been given a rustproof treatment or wash.

[0026]If the positioner is constructed of one material, such as the preferred 9 gauge wire, assembly cost is minimized and waste is reduced. Such cost savings can be realized in a number of ways. For example, because spines, crossbars, and rings can all be purchased from the same supplier, i.e. the metal or wire supplier, rather than purchased from separate suppliers, bulk purchasing power should be recognized.

Similarly because of the ease of manufacturing, those practicing the present teachings may be able to produce the positioner themselves, thereby eliminating the need for an additional prefabricator, which results in cost savings. Further cost reductions arise by virtually eliminating waste associated with the production process. By cutting metal or wire to the correct length to form the various components, virtually all starting material can be used, resulting in increased efficiency and cost savings. Similarly, by cutting metal or wire to the correct length to form the various components, there is essentially no Λvaste produced, thereby reducing costs associated with waste disposal.

[0027]Others may desire to form positioners of the present invention out of other materials, such as other plastics, woods, or ceramics, or out of a combination of other materials and metals. All such combinations would be within the scope of the present invention.

[0028]Figure 4 shows positioner 38 of Figure 3 on a CMU 10. Positioner 38 rests on the surface 18 of the CMU through rests 46 and 47. Preferably, rests 46 and 47 are in substantially the same linear orientation with one another and are in substantially the same plane, which would be, in this embodiment, the plane of surface 18. Further, in this embodiment the linear orientation of rests 46 and 47 is substantially parallel to the linear orientation of the midsection of spine 40. Others may desire to offset the linear orientation of rests 46 and 47 or may desire to orient rests 46 and 47 in different planes, which would be within the scope of the present invention. Rests 46 also facilitate positioner 38 insertion into channel 11.

[0029]Rests 46 allow a portion of spine 40 to extend into channel 11. Preferably the portion of spine 40 for inserting in channel 11 is sized to frictionally fit within channel 11. In this embodiment, the effects of rests 46 and 47 prevent further widthwise movement of the positioner. Crossbar 70 also inserts into channel 11 and is preferably sized to frictionally fit within the interior walls of channel 11. In this embodiment, crossbar 70 prevents lengthwise movement of the positioner. The fit of the crossbar 70 also prevents positioner rotation about the axis of spine 40. Ring 60, which bifurcatingly attaches to the spine 40, and in this embodiment, also attaches to the crossbar 70, rests within channel 11. Rebar 80 is shown inserted into second rebar aligner 64 of ring 60. While in this embodiment, the spine 40 orients widthwise, and crossbar 70 orients lengthwise, others using other embodiments, may prefer to orient the spine lengthwise and the crossbar widthwise, which would be within the scope of the present invention. Still in other embodiments, the crossbar may provide widthwise or lengthwise stability by contacting other portions of the CMU, or other portions of the CMU in combination with the interior walls of the channels of the CMU. Further, other structural embodiments may include various other ways to span the hollow core or channel of the CMU and make engagement with the inner side of the hollow core of the CMU while still retaining contact with the upper face of the CMU.

[0030]Figure 5 shows a side schematic view of several courses of CMU 10 with installed embodiments of the positioner and rebar. A plurality of CMUs 10 are stacked upon one another in courses. A terminated rebar 8OA is positioned by rebar positioner 38A. An additional rebar 80B can be positioned alongside rebar 80A for the desired overlap, and a further CMU course can be added. Concrete is poured into the channels, typically filling four or five courses, up to grout lift 500. Once that concrete sets, a further course of CMU (CMU 10A) can be applied and rebar positioner 38B can be positioned on new CMU 1OA. An additional rebar 80C can then be positioned on the top of the poured concrete, forming the reinforcement bottom leg for the next series of courses up to the next grout lift 502. On top of the course (CMU 10B) immediately below the grout lift 502, a further rebar positioner 38C is put in place as an overlapper, so that the two rebars overlap and are held in position by the two rebar positioners 38C and 38B. Then, when the upper course (CMU 10C) is added and a further grout lift level 502 is added, the process can be repeated. It will be appreciated that joints between the CMUs are mortared, as is conventional. It will further be appreciated that by using the preferred embodiments, the positioner stays in position and holds the rebar hi position centrally within the channel of the CMU, despite the application of vibration, and throughout the laying of other courses on the laid course, so that remediation and repair work are kept to a minimum. Also, the minimal cross section of the preferred embodiments provides little resistance to the flow of concrete being introduced into the channel, reducing the likelihood of void formation.

[0031]Figures 6-10 show other embodiments of the present invention. Figure 6 shows an embodiment where the ring 660 is attached to the spine 640 without attachment to the crossbar 670. Figure 7 shows an embodiment where two rings 760 are used to increase the number of rebar positioning options, which could be used to provide increased rebar overlapping, for example, to construct taller structures or to construct more stable structures. Figure 8 shows an embodiment where the ring 860 surrounds the intersection 820 of the spine 840 and the crossbar 870. Such an embodiment could be used to increase the number of rebar aligners from two to four without requiring an additional ring. Figure 9 shows an embodiment where the ring 920 attaches to the crossbar 970. Figure 10 shows an embodiment where two rings 940 attach to the crossbar. [0032]Those skilled in the art will recognize that CMUs are manufacture primarily in standard sizes, such as 6", 8", 10", 12", and 14" sizes, arid also come in custom, nonstandard, or miscellaneous sizes. For any size of CMU, standard or otherwise, the present invention may be achieved using a variety of dimensions, but some dimensions may be preferable.

[0033]For example, for positioners for positioning rebar in 12" CMUs, preferably, the positioner has a spine length of between about 8" to about 12", and more preferably has a length of about 10-12/16". The positioner has a spine midsection length of between about 7" to about 9", preferably about 8-1/8". The positioner also preferably includes first and second spine rests, which have a length of between about 1 inch to about 2 inches, and preferably have a length of about 1-5/16". The crossbar has a length from between about 6" to about 8", and preferably has a length of about 7". The ring is preferably substantially elliptical and has a major axis between about 2" and about 4", more preferably about 2-1/2"; and has a minor axis between about ¹A" and about 2", more preferably about 1". In alternate embodiments, the position of the crossbar on the spine varies and can be adjusted to accommodate various ring sizes or to accommodate two or more rings. For example, for embodiments using only a single ring, the crossbar may be positioned to be about 3-7/16" off the interior of the CMU channel wall, with the ring approximately over the midpoint of the spine. If two rings are used, however, each ring may be positioned to be about 2-1/2" off the interior of the CMU channel wall, with the crossbar approximately over the midpoint of the spine. [0034] Similarly, for positioners for positioning rebar in 8" CMUs, preferably, the positioner has a spine length of between about 5" to about 7", and more preferably has a length of about 6-12/16". The positioner has a spine midsection length of between about 3" to about 6", preferably about 4-5/8". The positioner also preferably includes first and second spine rests, which have a length of between about 1 inch to about 2 inches, and preferably have a length of about 1-5/16". The crossbar has a length from between about 4" to about 6", and preferably has a length of about 5". The ring is preferably substantially elliptical and has a major axis between about 2" and about 4", more preferably about 2-1/2"; and has a minor axis between about Vz" and about 2", more preferably about 1". In the preferred embodiments, the position of the crossbar on the spine varies and can be adjusted to accommodate various ring sizes or to accommodate two or more rings. For example, for embodiments using only a single ring the crossbar may be positioned to be about 1-1/2" off the interior of the CMU channel wall, with the ring approximately over the midpoint of the spine. If two rings are used however each ring may be positioned to be about 7/8" off the interior of the CMU channel wall, with the crossbar approximately over the midpoint of the spine. [0035]Those skilled in the art will be able, using proportions determined from the dimensions provided or other dimensions, to create various embodiments for any number of CMU sizes.

[0036]Numerous characteristics and advantages have been set forth in the foregoing description, together with details of structure and function. The novel features are pointed out in the appended claims. The disclosure, however, is illustrative only, and certain modifications and improvements will occur to those skilled in the art upon reading the foregoing description. It should be understood that all such modifications and improvements have been omitted for the sake of conciseness and readability, but are properly within the scope of the following claims.

Claims

We claim:

1. A rebar positioner comprising: a spine having a spine midsection, a first spine end, and a second spine end; a ring attached to the spine near the spine midsection; and a crossbar attached to the spine near the spine midsection, the crossbar having a crossbar midsection, a first crossbar end, and a second crossbar end.

2. The positioner of Claim 1, wherein the first spine end includes a first rest and the second spine end includes a second rest.

3. The positioner of Claim 2, wherein the first rest is offset from the spine midsection, and wherein the second rest is offset from the spine midsection.

4. The positioner of Claim 3, wherein the first rest and the second rest are integral with the spine.

5. The positioner of Claim 3, wherein the first rest is substantially inline with the second rest.

6. The positioner of Claim 5, wherein the first rest and the second rest have portions substantially parallel with the spine midsection.

7. The positioner of Claim 1 , wherein the ring is bifurcated by its attachment to the spine.

8. The positioner of Claim 1 , wherein the crossbar is attached to the spine at the crossbar midsection.

9. The positioner of Claim 8, wherein the crossbar is attached to the spine at the crossbar midpoint.

10. The positioner of Claim 8, wherein the crossbar is substantially perpendicular to the spine.

11. The positioner of Claim 9, wherein the crossbar is in contact with the ring.5

12. The positioner of Claim 9, wherein the crossbar is attached to the spine through the ring.

13. The positioner of Claim 1 , wherein the positioner is at least partially formed ofU metal.

14. The positioner of Claim 1 , wherein the positioner is at least partially formed from a group of steel metal wires selected from the group consisting of 6 gauge, 7 gauge, 8 gauge, 9 gauge, 10 gauge and 11 gauge.

15. The positioner of Claim 13 , wherein the positioner is at least partially coated in a rustproof coating.

16. The positioner of Claim 13 , wherein the positioner has at least partially been given a rustproof treatment.

17. A rebar positioner comprising: a spine having a midsection, a first end, and a second end, wherein a part of the first end is offset to form a first rest and a part of the second end is offset to form a second rest substantially in line with the first rest; a ring having a perimeter and attached to the spine near the spine midsection with portions of the ring on either side of the spine defining areas sized to receive rebar; and a crossbar attached to the spine.

18. The rebar positioner of Claim 17, wherein the positioner is sized for positioning rebar in 12" CMUs.

19. The rebar positioner of Claim 17, wherein the positioner is sized for positioning rebar in 8" CMUs.

20. The rebar positioner of Claim 17, wherein the positioner is sized for positioning rebar in CMU selected from the group consisting of 6" CMU, 10" CMU, and 14" CMU.

21. The positioner of Claim 17, wherein the ring is substantially elliptical and has a major and minor axis.

22. The positioner of Claim 17, wherein the crossbar is attached to the spine near the ring.

23. A rebar positioner comprising: a spine having a spine midsection, a first spine end, and a second spine end; a crossbar attached to the spine near the spine midsection, the crossbar having a crossbar midsection, a first crossbar end, and a second crossbar end; and a ring attached to the crossbar.

24. A method of making a rebar positioner comprising: attaching a ring to a spine near the spine midsection; and attaching a crossbar to the spine near the spine midsection.

25. The method of Claim 24, further including forming a first rest on a first spine end and a second rest on a second spine end by bending the spine to offset the rests from the ring.

26. The method of Claim 25, wherein the positioner at least partially comprises metal.

27. The method of Claim 26, wherein the attaching includes welding.

28. A method of constructing walls comprising : laying a first course of CMUs so that the CMUs have generally vertically oriented channels; mounting a rebar positioner having a ring member onto a laid CMU to provide positions for at least two rebar so that at least part of the rebar positioner is recessed within the channel; and laying a second course of CMUs so that a CMU of the second course has a vertically oriented channel over the first course so a CMU channel from the first course at least partially aligns with the CMU channel from the second course and rebar positioned in ring members can extend through the aligned CMU channels.

29. The method of Claim 28, including inserting a first rebar into one of the ring members.

30. The method of Claim 29, further including laying at least a third course of CMU having a channel.

31. The method of Claim 30, further including inserting a second rebar into another of the positions of the ring member.

32. The method of Claim 31 , further including pouring concrete into the channel containing the positioner and rebar.

33. The method of Claim 28, wherein the positioner is the positioner of Claim 1.

34. The method of Claim 28, wherein the positioner is the positioner of Claim 17.