Patent Application
20150068265
The present invention relates, generally, to devices and processes for cutting, bending, and shaping rebar; and, more particularly, to field-operable devices and processes for cutting, bending, and shaping rebar wherein an hydraulic pressure source is used in association with a table-like structure to drive rebar cutting, bending, and shaping functions.
As is well-known in the construction industries, rebar (short for reinforcing bar), is a steel bar commonly used as a tensioning means for reinforced concrete and like structures, such as masonry. When rebar is to be used in association with such concrete structures, its function is to hold the concrete in compression—wherein the concrete is strongest. The rebar, then, functions to carry and spread the tensile loads, provide resistance to concentrated and/or bending loads, and add stiffness to the structure.
Rebar is sized (in the U.S.) from #2 bar size, corresponding to an approximate nominal diameter of ¼ inch, to #18 bar size, corresponding to an approximate nominal diameter of 2¼ inches; although greater diameter, “jumbo” bars are commonly available for large structures. Rebar is available in a number of different grade designations, and a variety of industry specifications have been established for control of rebar chemical composition, mechanical properties (such as, for example, yield strength, percentage of elongation, tensile strength, ductility, heat treatment, and the like), and surface coatings (such as, for example, zinc/galvanized coatings, epoxy coatings, and the like).
In use and application, a rebar structure is typically fabricated on-site and in advance of the concrete pour. A structural engineer or architect will have specified, in advance, the component sizes, lengths, and shapes, as well as the assembly, welding, and/or tying configuration, for each rebar structure. Depending upon the size and nature of the job, these components can be fabricated in-advance and transported to the job site for subsequent assembly, or they can be fabricated on-site using site-stocked materials.
For large jobs, rebar elements are cut (most often by shearing) and shaped, in advance, at a rebar fabrication facility using high-capacity hydraulic equipment. For smaller jobs, though, rebar elements are most often cut, bent, and shaped on-site. As will be described below, because power sources, such as electrical lines, are often unavailable on the job site during this phase of construction, on-site rebar cutting, bending, and shaping operations are typically performed by-hand. One form of manual rebar bender, known as a Hickey, is often used. The Hickey operates through manually applied leverage, and bending operations can be inaccurate, time consuming, and physically demanding.
Of course, it should be readily apparent that the force required to complete each cutting, bending, and shaping operation is dependent upon, for example, the size of the rebar, its grade, and its associated chemical and mechanical properties, such as were described above. Accordingly, only smaller sizes of rebar—typically no larger than #6 (¾ inch nominal diameter)—can be manually processed on-site.
Because electrical power often is not yet available on-site during grading and foundation pouring phases of construction, electrically powered rebar cutting, bending, and shaping tools may not be convenient or usable. Any powered tool would, accordingly, require a different and conveniently available power source for its operation and use. Additionally, in order to most efficiently and safely process rebar component parts, workers should have access to a processing station that can be conveniently placed near on-site rebar material staging areas, and subsequently relocated as-required. Such a processing station should be capable of accurately and safely cutting, bending, and shaping rebar component parts; it should be effective, convenient, and simple to operate; it should be adjustable to accommodate its operator; and it should be capable of processing a variety of sizes and grades of rebar.
Accordingly, it is to the disclosure of such devices and related processes that this disclosure is directed.
In general, the present disclosure is directed to embodiments of a rebar processing station meeting the aforedescribed requirements, and taking the form of an hydraulically powered rebar cutting, bending, and shaping table. Specifically, and pursuant to a preferred embodiment of the hydraulically powered rebar cutting, bending, and shaping table of the present disclosure, a table, preferably formed from durable, structural steel component parts, is configured with a rebar cutting assembly and with a rebar grasping, bending, and shaping assembly.
In some embodiments, the rebar cutting assembly comprises a pair of hardened shearing plates or dies, one of which is preferably stationary and one of which articulates about a pivot center. Each shearing plate or die comprises one or more peripheral, U-shaped slot or channel, configured to align with a respective, corresponding U-shaped slot or channel in the other adjacent shearing plate or die. Each U-shaped slot or channel is appropriately sized to receive a rebar therewithin, and when operating thereupon, cuts the rebar by shearing force at the interface between the adjacent shearing plates. In some embodiments, left and right-hand U-shaped slots or channels may be provided within each shearing plate or die for the convenience of the operator.
In some embodiments, a rebar grasping, bending, and shaping assembly comprises rebar grasping means, a shaping plate or die, and a movable former, such as a roller. The rebar grasping means may comprise a clamp formed by cooperative interaction between a first, fixed-position, tapered clamp portion and a second, slidable, cooperatively-tapered clamp portion. In operation, one side of a rebar is placed adjacent a fixed-position shaping die, and the slideable, tapered clamp portion is engaged against the opposite side of the rebar; thereby, clamping or grasping the rebar between the fixed-position shaping plate or die and the clamp in a stable and stationary position. Provided that the distal portion of the rebar is of sufficient length to be engaged by the movable former, which in some embodiments takes the form of a hardened steel roller operating within an arcuate field of travel, the rebar may be bent and shaped by operation of the movable former against the rebar, bending the rebar about the adjacent, fixed-position shaping plate or die. Provided, of course, that the applied bending forces are sufficient to exceed the yield strength of the rebar, the bending operation is permanent; and the rebar, accordingly, is shaped to the desired configuration.
Because these rebar cutting, bending, and shaping processes often occur contemporaneously with site preparation activities, such as site excavation, grading, and compaction; and, because construction materials must be staged and moved about the construction site, hydraulically-equipped loaders, excavators, tractors, ancillary hydraulic motors and/or power packs, and similar machines, are typically available on-site. Accordingly, hydraulic power out-takes and/or outputs typically associated with such hydraulically-equipped machines are often available for use in association with the hydraulically powered rebar cutting, bending, and shaping table of the present disclosure.
Similarly, because the hydraulically powered rebar cutting, bending, and shaping table of the present disclosure can be placed nearly anywhere on-site, the aforedescribed hydraulically-equipped loaders, excavators, tractors, and similar machines can be enlisted to transport and relocate the table about the site, as required. Accordingly, the table may be provided with appropriate features allowing cooperative engagement of the table with appropriate attachments and/or implements associated with such machines.
The hydraulically powered rebar cutting, bending, and shaping table of the present disclosure can be treated against weathering and rusting. Table legs can be made extensible, as with cooperating pin and hole arrangements. Shields and/or covers may be provided for worker safety during table operation, and to protect moving components of the table against impact and damage when not in operation.
In use and operation, a rebar is placed within the U-shaped slot or channel of the cutting assembly, the preferred cut-point is aligned along the shear interface between the adjacent shearing plates, and the cutting assembly is actuated so as to cut the rebar to its preferred length. One side of the rebar is then placed adjacent the fixed-position shaping die, and the slideable, tapered clamp portion is engaged against the opposite side of the rebar; thereby, clamping or grasping the rebar between the fixed-position shaping plate or die and the clamp in a stable and stationary position. The movable former is actuated; whereby, provided that the distal portion of the rebar is of sufficient length to be engaged by the movable former, the rebar is be bent and shaped by operation of the movable former against the rebar, bending the rebar about the adjacent, fixed-position shaping plate or die. Provided, of course, that the applied bending forces are sufficient to exceed the yield strength of the rebar, the bending operation is permanent; and the rebar, accordingly, is shaped to the desired configuration. The aforedescribed process, or subprocesses thereof, may be repeated as-required to bring each rebar into conformance with its corresponding specification.
These and other features and advantages of the various embodiments of devices and related systems comprising , as set forth within the present disclosure, will become more apparent to those of ordinary skill in the art after reading the following Detailed Description of Illustrative Embodiments and the Claims in light of the accompanying drawing Figures.
Accordingly, the within disclosure will be best understood through consideration of, and with reference to, the following drawing Figures, viewed in conjunction with the Detailed Description of Illustrative Embodiments referring thereto, in which like reference numbers throughout the various Figures designate like structure, and in which:
It is to be noted that the drawings presented are intended solely for the purpose of illustration and that they are, therefore, neither desired nor intended to limit the invention to any or all of the exact details of construction shown, except insofar as they may be deemed essential to the claimed invention.
In describing the several embodiments illustrated in the Figures, specific terminology is employed for the sake of clarity. The invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose. Additionally, in the Figures, like reference numerals shall be used to designate corresponding parts throughout the several Figures.
Illustrated in
As may be seen with reference to
In some embodiments, rebar cutting assembly 200 comprises a pair of hardened shearing plates or dies 202, 204. In the embodiment shown, shearing plate 202 is preferably stationary and firmly affixed to table 100, while shearing plate 204 preferably articulates about pivot center 206. Pivot center 206 may take the form of a hardened steel pin or bolt and cooperating hole.
Each shearing plate or die 202, 204 comprises one or more peripheral, U-shaped slot or channel 208, configured to align with a respective, corresponding U-shaped slot or channel 208 in the other adjacent shearing plate or die. Each U-shaped slot or channel 208 is appropriately sized to receive rebar R therewithin, and when operating thereupon, cuts rebar R by shearing force at the interface I between the adjacent shearing plates. In some embodiments, left and right-hand U-shaped slots or channels 208 may be provided within each shearing plate or die 202, 204 for the convenience of the operator.
In some embodiments, rebar grasping, bending, and shaping assembly 300 comprises rebar grasping means 302, fixed-position shaping plate or die 304, and a movable former 306, such as a bearing-mounted roller. Rebar grasping means 302 may comprise a clamp formed by cooperative interaction between a first, fixed-position, tapered clamp portion 308 and a second, slidable, cooperatively-tapered clamp portion 310.
Best seen with reference to
With continuing reference to
Provided that the distal portion of the rebar is of sufficient length to be engaged by movable former 306, which in some embodiments takes the form of a hardened steel, bearing-mounted roller operating within an arcuate field of travel defined by slot 314, rebar R may be bent and shaped by operation of movable former 306 against rebar R, bending rebar R about adjacent, fixed-position shaping plate or die 304. Provided, of course, that the applied bending forces are sufficient to exceed the yield strength of rebar R, the bending operation is permanent; and rebar R, accordingly, is shaped to the desired configuration.
Because these rebar cutting, bending, and shaping processes often occur contemporaneously with site preparation activities, such as site excavation, grading, and compaction; and, because construction materials must be staged and moved about the construction site, hydraulically-equipped loaders, excavators, tractors, ancillary hydraulic motors and/or power packs, and similar machines, are typically available on-site, and can be enlisted to transport and relocate table 100 about the site, as required. Accordingly, table 100 may be provided with appropriate features, such as transport assembly 400, allowing cooperative engagement of table 100 with appropriate attachments and/or implements associated with such machines.
Returning to
Once the hydraulically powered rebar cutting, bending, and shaping table 100 of the present disclosure has been placed in a desired on-site location, the aforedescribed hydraulically-equipped loaders, excavators, tractors, ancillary hydraulic motors and/or power packs, and similar machines can be conveniently utilized to power table 100 through use of such hydraulic power out-takes and/or outputs typically available on such hydraulically-equipped machines. With continuing reference to
Best seen with reference to
As may be seen in
Similarly, and with continuing reference to
In use and operation, and with continuing reference to
In some embodiments, table legs 102 can be made extensible, as with cooperating pin and hole arrangements associated with multi-part legs. In some embodiments, table legs 102 may be provided with plate cleats 104 to provide stability and leveling capabilities.
In some embodiments, shields and/or covers 106 may be provided for worker safety during table operation, and to protect moving components of table 100 against impact and damage when table 100 is not in operation. In some embodiments, shields and/or covers 106 may be affixed to table 100 via tether 108. In some embodiments, set-aside shields and/or covers 106 may be supported, when not in use, by hangers 110 upon table 100, best seen with reference to
It will be apparent that rebar of any of a variety of sizes, shapes, and/or materials may be used in association with table 100, so long as appropriate to the configuration and power profile of the table.
It will also be apparent that, in other embodiments, fixed-position shaping plate or die 304 may be provided in an alternative shape and/or size than has been described and depicted herein, in order to accommodate other, different, and/or further bend specifications. Specifically, in some embodiments, a fixed-position shaping plate or die 304 having a length of approximately 9-10 inches from front radius to heel may be preferred for projects in which rebar bending specifications call for compact, multiple (or consecutive) bends, such as those that might be found, for example, within rectangular-shaped rebar sections used within footings. It will be apparent that such length of fixed-position shaping plate or die 304 will allow one to form, for example, a 12 inch rectangular rebar footing section, without interference or obstruction by fixed-position shaping plate or die 304. Of course, it will be further apparent that appropriate adjustments may be necessary in the design and/or configuration of table 100, and associated elements, in order to accommodate other or alternative forms of fixed-position shaping plate or die 304.
It will be further apparent that, in some appropriately configured embodiments, table 100 may be pneumatically and/or electrically powered, in lieu of, in association with, or in addition to, the use of hydraulic power systems of the type that have been described herein.
Having thus described exemplary embodiments of the subject matter of the present disclosure, it is noted that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope and spirit of the present invention. For example, while the disclosure set forth hereinabove has been provided with reference to materials such as construction rebar, the subject matter could be extended to use in association with many other relatively slender, cylindrical, solid or tubular, bendable materials which preferably may be cut by shearing without performance-degrading deformation adjacent the shear plane.
Accordingly, the present subject matter is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims.
The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/875,949, which was filed on Sep. 10, 2013, the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61875949 | Sep 2013 | US |
