Collated rebar clinch clip

A collated rebar clinch clip has three components including a pair of spaced U-shaped crimp elements and a U-shaped bridge element connecting the crimp elements. The crimp elements and bridge element are cut from continuous lengths of stock material. A plurality of clinch clips are joined together by a pair of cords to form a collated series of clinch clips that may be arranged in a linear series or spirally wound to form a coil. The tool includes a frame, a die set with a sliding blade and a fixed anvil, an actuator to linearly move the blade relative to the anvil, and a magazine to hold collated clinch clips for sequential delivery between the blade and anvil to tie together a first length of rebar extending through the bridge element and a second orthogonal length of rebar extending through the crimp elements.

BACKGROUND OF THE INVENTION

Technical Field

The present invention relates to clips and, more particularly, to collated rebar clinch clips used for tying rebar together.

Background Art

Concrete is a composite material made of fine and coarse aggregate bonded together with a fluid cement. After being poured and over time, it hardens and cures into a stone-like substance.

Concrete is a convenient material used to construct roads, buildings, and other manmade structures. It is very strong in compression, but it is weak in tension as the concrete holding the aggregate together can crack allowing the structure to fail. To prevent this, steel reinforcing bars, or rebar, is placed within the concrete during construction to add tensile strength and increase the tensile load that can be carried. Rebar is supplied as long, thick wires or rods and is usually arranged horizontally or vertically in a grid or matrix pattern to form a flat mat or curtain, or in a three-dimensional cage. Before concrete is poured over the rebar to encase it, the lengths of transversely intersecting rebar are joined together by short lengths of thin steel wire that is wrapped around the joints to hold the rebar fixedly together preventing their relative movement. This is typically done manually and is a costly and backbreaking operation. It requires a worker to carry a wire reel or a supply of short wires and to constantly bend over while twisting the wires around the rebar with pliers or some other tool.

While integrally-formed, H-shaped clips that may be used to tie the rebar together could be punched out of thin, flat stock material, the manufacture of such clips does not lend itself to efficient configurations and would create significant amounts of waste.

BRIEF SUMMARY OF THE INVENTION

In accordance with the invention, many of the problems associated with time-consuming, backbreaking labor while tying rebar together are avoided by providing collated rebar clinch clips and a crimping tool with a magazine to hold the clips.

The devices disclosed herein provide an effective means for tying lengths of rebar together that is quicker, less costly, and makes for a tighter connection.

In one aspect of the invention, a rebar clinch clip is constructed with three basic components, namely, a U-shaped bridge element overlying a first rebar and a pair of spaced U-shaped crimp elements fixed to the ends of the bridge element and overlying a second rebar that underlies and is orthogonal to the first rebar. In accordance with the invention, a collated series of clips is provided that may be loaded into a magazine that feeds a crimping tool operable by a worker.

In one embodiment of the invention, the bridge element is a U-shaped wire welded to the end sections.

In another embodiment of the invention, the bridge element is a strip mechanically joined to the crimp elements.

A feature of the invention are severable flexible cords connecting a series of clips together and slots formed in the crimp elements for receiving the cords that may be closed to hold the cords within the slots and thereby to the clips.

In accordance with the invention, a clip crimping tool includes a frame, an anvil, a blade, a magazine to feed collated clips between the anvil and blade, and an actuator to move the blade and anvil together to crimp a clip around rebar placed between the blade and anvil.

A feature of the invention is that the actuator includes a handle spaced from the blade and anvil such that a worker may operate the tool standing upright without bending over when the intersecting rebar to be joined is located at the worker's feet.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Collated Rebar Clinch Clips

InFIGS. 1-18, a first embodiment of a collated rebar clinch clip, generally designated100, for fixing two lengths of rebar together is shown. As best seen inFIGS. 13-18, the clip100is positioned over two lengths rebar, a longitudinally-extending upper rebar150and an underlying laterally-extending lower rebar152orthogonal to and abutting the bottom of the upper rebar150.

As seen inFIGS. 1-6, an individual clip100, which may be made of low carbon steel, has three components, namely, a pair of crimp elements102a,102band an arched bridge element104, connecting the crimp elements102a,102bthat are located below in laterally spaced relation.

Each of the crimp elements102a,102bis a U-shaped strip having a center bight portion106and a pair of parallel downwardly-extending legs108a,108b. The legs108a,108bof the crimp elements102a,102bdefine a pair of aligned, laterally-extending openings110a,110bthrough which the lower rebar152extends. The bight portions106of the crimp elements102a,102bare arcuate, but may have a polygonal shape or any other suitable configuration. The crimp elements102a,102bhave a rectangular cross-section.

The bridge element104is a U-shaped wire having a center arched bight portion116and a pair of parallel downwardly-extending arms118a,118bwith fingers120a,120bextending laterally outward. The bridge fingers120a,120boverlap and fixed to the top surface of the bight portion106of the crimp elements102a,102bby attachment means, such as by welding or by any suitable mechanical connection. The arms118a,118bof the bridge element104define an opening122that is orthogonal to openings110a,110band through which the upper rebar150extends. Similar to the crimp elements102a,102b, the bridge bight portion116is arcuate, but may have a polygonal shape or any other suitable cross-sectional configuration. The bridge element104has a circular cross-section.

Intermediate the lateral ends of the bridge fingers120a,120band the outward edge of each crimp element102a,102bare longitudinal slots124a,124b. As will be apparent later, the slots124a,124bhave a size and configuration such that when the crimp elements102a,102bare formed with the bight portions106being bent, the slots124a,124bwill be upwardly opening and have a depth allowing a collating cord to be positioned therein as seen inFIGS. 7-8.

The diameter of the bight portion116of the bridge element104and the vertical distance between the lower surface130of the bridge bight portion116and the lower surface132of the crimp element bight portion106have a dimension slightly larger than the diameter of the upper rebar150. The diameter of the bight portion106of the crimp elements102a,102bis slightly larger than the diameter of the lower rebar152. The height of the crimp element legs108a,108bis of a length permitting the legs to wrap around the bottom of the rebar152as seen inFIG. 18.

As seen inFIGS. 7 and 8, a plurality of clinch clips100are collated into a connected side-to-side series, generally designated140, by means of a pair of parallel thin polyethylene cords142a,142b. Each clip100is mechanically attached to the cords142a,142bby compressing the sides of the open slots124a,124binward to close them slightly thereby holding the cords142a,142band fixing the clip100in position along the cords136a,136b. The relatively thin cords142a,142bare easily severed to separate individual clips when they are later attached to the lengths of rebar.

FIGS. 13-18show the clip100without the collating cords in position on two orthogonally-oriented rebars150,152.FIGS. 13-17show an open clip100with the bridge element104overlying and resting on the upper rebar150and the crimp elements102a,102bresting on and overlying the lower rebar152on either lateral side of the upper rebar150.FIG. 18shows a clip100with the legs108a,108bof the crimp elements102a,102bdeformed to hold the clip100on the lower rebar152and thereby hold both the upper rebar150and lower rebar152in fixed relation.

As seen, the clinch clip100is formed from three separate components, namely, the crimp elements102a,102band the bridge element104. The parallel crimp elements102a,102bare spaced along the rebar152and have an arcuate connecting bight portion106overlying the rebar152. The bight portion116connects the ends of the two spaced parallel legs108a,108bto define U-spaced openings110a,110borthogonal to the lower rebar152having a dimension allowing fitment over the rebar152that extends in one direction.

The bridge element104has an arcuate bight portion116overlying the rebar150and connects the crimp elements102a,102btogether. The arcuate bight portion116connects the ends of the two spaced parallel arms118a,118bto define U-shaped opening122orthogonal to the upper rebar150having a dimension allowing fitment over the rebar150that extends in a second direction.

To form a complete clip, the metal crimp elements102a,102bare fused as by welding to the bridge fingers120a,120bextending outward and overlapping the bight portions106of the crimp elements102a,102b. To bind two transverse or orthogonal rebars together, the clip100is placed over the rebars150,152with the legs108a,108bof the crimp elements102a,102bbeing forcefully deformed to at least partially wrap around the lower rebar. For round rebar, the arcuate bight portions have a semicircular shape.

FIGS. 19-21show a second embodiment of a rebar clinch clip prior to forming. The clip, generally designated200, has three components, namely, a pair of crimp elements202a,202band a bridge element204connecting the crimp elements202a,202bthat are located in laterally spaced relation. The crimp elements202a,202band the bridge element204are formed from metal, such as steel, and have a rectangular cross-section.

Each of the crimp elements202a,202bis a strip having a center portion206and a pair of legs208a,208bextending outwardly therefrom. The legs208a,208bof the crimp elements202a,202bwhen formed define a pair of aligned, laterally-extending openings through which the lower rebar152will extend. Formed in the center portion206of each crimp element202a,202bis a pair of spaced, upright prongs212a,212bspace inward from one edge and slots224a,224bintermediate the prongs212a,212band the opposite edge.

The bridge element204is a bar having a center portion216and arms218a,218bextending outwardly therefrom. The arms218a,218bof the bridge element204when formed define a longitudinally-extending opening through which the upper rebar150will extend.

The bridge element204has a pair of opposed cutouts226a,226balong each longitudinal edge spaced inwardly from lateral edges. The clip200is fixedly assembled by placing the bridge element204over the crimp elements202a,202bby positioning the prongs212a,212bwithin the respective cutouts226a,226band then bending the prongs212a,212binwardly down over the top of the bridge element204to mechanically attach crimp elements to the overlapping bridge. Slots224a,224bare formed in each of the crimp elements202a,202bintermediate the lateral ends of the bridge element204and the outward edge of each crimp element202a,202b.

FIG. 22shows a third embodiment of a rebar clinch clip prior to shaping of the clip elements into U-shaped forms. The clip, generally designated300, has three components, namely, a pair of crimp elements302a,302band a bridge element304connecting the crimp elements302a,302bthat are located in laterally spaced relation. The crimp elements302a,302band the bridge element304are formed from metal, such as steel, and have a rectangular cross-section.

Each of the crimp elements302a,302bis a strip having a center portion306and a pair of legs308a,308bextending outwardly therefrom. The legs308a,308bof the crimp elements302a,302bwhen formed define a pair of aligned, laterally-extending openings through which the lower rebar152will extend. Formed in the center portion306of each crimp element302a,302bis a pair of spaced prongs312a,312bspaced inward from one edge and a slot324intermediate the prongs312a,312band the opposite edge.

The bridge element304is a bar having a center portion316and arms318a,318bextending outwardly therefrom. The arms318a,318bof the bridge element304when formed define a longitudinally-extending opening322through which the upper rebar150will extend. The edges of the center portion316are curved inwardly defining a narrow segment328so that when collated clips are coiled the upright bridges of adjacent clips are not in interference and the clips may overlap one another.

The bridge element304has a pair of opposed cutouts along each longitudinal edge spaced inwardly from lateral edges. The clip300is fixedly assembled by placing the bridge element304over the crimp elements302a,302bby positioning the prongs312a,312bwithin the respective cutouts and then bending the prongs312a,312binwardly down over the top of the bridge element304. Formed in each of the crimp elements intermediate the lateral ends of the bridge element304and the outward edge of each crimp elements are longitudinal slots324a,324b.

FIGS. 23-27show a fourth embodiment of a rebar clinch clip, generally designated400, having three components, namely, a pair of crimp elements402a,402band an arched bridge element404connecting the crimp elements402a,402bthat are located in laterally spaced relation. The crimp element s402a,402band the bridge element404are formed from metal, such as steel, and have a rectangular cross-section.

Each of the crimp elements402a,402bis a U-shaped strip having a center bight portion406and a pair of downwardly extending legs408a,408bhaving a straight edge and a tapering edge. It will be understood that when the legs408a,408bare severed from the continuous strip of raw material by cutting at an angle, one side of a leg408a,408bis complementary to the other side of a preceding or succeeding leg thereby saving material and allowing for longer legs, if desired. The legs408a,408bof the crimp elements402a,402bdefine a pair of aligned, laterally-extending openings410through which the lower rebar152extends. As been seen inFIG. 27, the legs408a,408bare longer than those shown inFIGS. 1-26so that they may be wrapped around the lower rebar152more completely without overlapping, since they will bypass one another so as to lie in side-by-side relation after crimping.

The bridge element404is a U-shaped wire having a center bight portion416and downwardly extending arms418a,418bwith fingers420a,420bextending laterally outward. The bridge fingers420a,420bare fixed to the top surface of the crimp elements402a,402bby any suitable means. The arms418a,418bof the bridge element404define a longitudinally-extending opening422through which the upper rebar150extends.

Intermediate the ends of the bridge fingers420a,420band the outward edge of each crimp elements402a,402bare longitudinal slots424a,424bhaving a size and configuration such that when the crimp elements402a,402bare formed with the bight portion406being bent, the slots424a,424bwill be upwardly opening and have a depth allowing a collating cord to be positioned and held therein.

Method of Manufacturing Collated Rebar Clinch Clips

As illustrated in development inFIGS. 9-12, completed clips100are formed in stages on a punch press with a progressive die (not shown). As is well known, such a press with properly constructed dies can perform punching, perforating, slitting, severing, bending, swaging, stamping and other operations. Usually, these operations are done on long strips, ribbons or webs of coiled, relatively thin, metal stock that is unrolled, flattened, fed into the press, and advanced in predetermined pitch increments during each press cycle.

InFIGS. 9-12, the stages of clip formation are shown. Typically, each stage, denoted by the letters A-F, takes place in a punch press as raw stock material is progressively indexed a predetermined distance through a series of die stations.

At the first station indicated at A, a pair of unformed thin metal blank strips170a,170bare advanced into the press in spaced, parallel relation. When the inbound strips170a,170bare advanced to a second station of clip formation indicated at B, a length of wire is welded, or otherwise attached, between the spaced strips170a,170bto form a straight connecting bridge172. The ends of the wire extend laterally to an intermediate point of each strip170a,170b. As the strips170a,170bare advanced, a bridge172will be formed in each clip that will eventually be produced.

At the third station indicated at C, slots124a,124bare punched in each of the strips170a,170blaterally outward of the ends of the bridge172and inward of the outer edges of the strips170a,170b. Elongate slots124a,124bin succeeding clips thereafter will be formed at predetermined intervals along the longitudinal axes of the strips.

At the fourth station indicated at D, individual partially-formed clips180are severed from the strips170a,170band the downward legs108a,108bare formed over a mandrel at each lateral side creating channels, or openings110a,110b. The clip180is then moved away from the line of upstream interconnected clips yet to be separated. The configuration of the severed clip180is shown in the front and side views ofFIG. 11. The legs108a,108bare now configured and sized to receive and accommodate within the openings110a,110ba laterally extending rebar.

When clip180is advanced to the fifth station indicated at E, the arch in the bridge172is formed over a mandrel defining a longitudinal tunnel, or opening122, as shown in the front and side views ofFIG. 12and is configured and sized to receive and accommodate within the opening122a longitudinally extending rebar.

At the sixth station indicated at F, collation of the clip strips takes place. Continuous parallel cords142a,142b, which other clips100have been previously attached, are positioned into respective slots124a,124band the sides of the clip pressed inward to close the slots slightly and hold the cords142a,142bwithin the slots124a,124b. The clips100are spaced slightly apart along the cords142a,142benabling the collated clips to be flexed relative to one another.

The collated clips100may be made into strips of clips arranged linearly in a series or they may be spirally coiled to form a roll of clips that is more compact.

Rebar Clinch Clip Installation Tool

As seen inFIGS. 28-45, a clip installation tool, generally designated500, includes a frame502, a die set, generally designated504, at the lower end of the frame502, an actuating mechanism, generally designated506, extending from the upper end of the frame502, and a clip magazine, generally designated508, for holding collated clips100that will be delivered sequentially one at a time to the die set504.

The frame502includes a pair of longitudinally extending side plates510a,510bheld in spaced relation by a plurality of laterally extending spacers, collectively designated512, and a plurality of nuts and bolts, collectively designated514.

The die set502includes a bifurcated anvil520fixed to the frame502and a bifurcated blade522movable toward and away from a crimping position with the anvil520. Lateral motion of the blade522at the lower end of the tool500is limited by the side plates510a,510band longitudinal motion by a blade guide524and a pair of spacers526a,526b.

The configuration of the anvil520, blade522, and blade guide524are best seen inFIGS. 40-45. As best seen inFIGS. 42 and 43, the anvil520has through hole530aand through holes530bformed in lugs532a,532bfor mounting the anvil520to the frame502and a pair of upwardly-opening concave finger elements534a,534bat the front with grooves536a,536bconforming to the shape and size of the legs of the clip100to accept and guide their movement along the anvil520.

As best seen inFIGS. 40 and 41, the blade522has top and bottom portions with a through hole540formed in the narrow top portion538and a pair of downwardly-opening concave finger elements542a,542bwith a concave surface544at the rear separated by U-shaped slot546with a groove548conforming to the shape and size of the top of a clip100. The concave elements534a,534band542a,542bgenerally correspond to the exposed outward surfaces of the rebar being tied together.

As best seen inFIGS. 44 and 45, the blade guide524has side lugs550a,550bheld in slots552a,552bin the side plates510a,510band an opening554defined by opposed spaced legs556a,556bhaving a cross-section generally conforming to the cross-section of a clip100. The opening554includes an arch558at its inner end and a chamfer557along the edges to guide clips into position within the opening554.

Herein, the tool500is used to connect rebar having a diameter of about ⅜ inch. However, the same tool may be modified for use with rebar of larger or smaller diameter by changing the blade, anvil, blade guide, and magazine that is being used.

The actuating mechanism506includes a pair of arms560a,560bpivotally mounted between the side plates510a,510b. The inner ends of the arms560a,560bare connected to one end of elongate drawbars562a,562bby way of links564a,564b. The other end of the elongate drawbars562a,562bare connected to the movable blade522. A plurality of spacers, collectively designated566, provide spacing between the various elements. The drawbars562a,562bare limited to linear movement by guide pins570that travel in longitudinal slots572formed in the side plates510a,510b, which may also limit the amount of drawbar travel.

Grip handles574a,574bat the outer ends of the arms560a,560bprovide means allowing a user to hold and operate the tool500. Upward motion of the handle ends of the arms560a,560bcloses the inner ends of the arms extending the links564a,564band thereby pushing the drawbars562a,562bdownward which in turn moves the blade522toward the anvil520. Conversely, pushing the handles574a,574bdownward opens the links564a,564band drawbars562a,562bretracting the blade522away from the anvil520.

The clip magazine508is attached to the frame502at its upper end by a horizontal multi-angled magazine arm580fixed to side plate510band its lower end by a bolting flange584between the anvil lugs532a,532b. The clip magazine508includes a housing590having a rectangular cross-section with two channels592a,592bseparated by an intermediate wall594, a cover596at one side, and a pusher mechanism600. The clip magazine508extends vertically from an upper end602having an opening604for loading collated clips140to a curved lower end606extending horizontally inward to deliver clips to the die set502. The collated clips140are loaded into the clip magazine508with the U-shaped bridge element104of the clips straddling the intermediate wall594and the legs108a,108bof the clips retained in their respective channels592a,592b.

The pusher mechanism600includes an elongate feed rail610with a generally rectangular cross-section, a pusher612mounted for travel along the feed rail610, and a spring614coiled around a spring rod616biasing the pusher612downward. The pusher612is fixed to one end of the spring rod616and includes a clip pusher618and a torsion spring620biasing the clip pusher618toward the top edge of the intermediate wall584. The upper end of the feed rail610is fixed to the center section of the magazine arm580and the upturned lower end of the feed rail610is fixed to mounting block622. Rod block624is fixed to the center section of the magazine arm580and includes an opening626through which the spring rod616is slidable. The pusher612has a pair of laterally-extending wings628allowing a user to manually pull the pusher612upward against spring pressure and a generally rectangular opening through which the feed rail610passes.

To load the clip magazine508, the pusher612is manually raised against the force of the coiled spring614by pulling upward on the pusher block wings628. Thereafter, collated clips140are loaded below the clip pusher618and the pusher612is released such that the clip pusher618moves against the rear of the loaded collated clips. During use, the coiled spring614will force the pusher612downward causing the clips to automatically be fed between the anvil520and the blade522when the blade522is retracted upward from the blade guide opening after clinching. It will be noted that as clips are removed from the magazine508, the pusher612will move downwardly on the fixed feed rail610and the spring rod616fixed to the pusher612will slide downwardly within the rod block624.

INDUSTRIAL APPLICABILITY

From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It will also be observed that the various elements of the invention may be in any number of combinations, and that all of the combinations are not enumerated here. It will be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. While specific embodiments of the invention have been disclosed, one of ordinary skill in the art will recognize that one can modify the materials, dimensions and particulars of the embodiments without straying from the inventive concept.

Other aspects, objects and advantages of this invention can be obtained from a study of the drawings, the foregoing disclosure and the attached claims.

It should be understood that the terms “top,” “bottom,” “forward,” “rear,” “rearward,” “upper,” “lower,” “inner,” “outer,” “side,” “lateral,” “end,” “height,” “width,” “length,” “horizontal,” “vertical,” and similar terms as used herein, have reference only to the structure shown in the drawings and are utilized only to facilitate describing the invention. The terms and expressions employed herein have been used as terms of description and not of limitation.

As used herein, the term “vertical” shall mean in a direction generally indicating the height of an object, such as distance between the top and bottom of the climping tool; the term “longitudinal” shall mean in a direction generally along the length of an object from front to back, such as the direction of the upper rebar extends as shown herein; and, the term “lateral” shall mean in a direction generally orthogonal to vertical and to longitudinal, such as the direction of the lower rebar extends as shown herein.

As used herein, the term “within” shall mean “to be partially or completely inside of”; the term “axial” refers to a direction that is substantially straight; the term “transverse” refers to a direction other than the axial direction (e.g., orthogonal or nonorthogonal).