US3198219A - Apparatus for producing a girder - Google Patents

Apparatus for producing a girder Download PDF

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Publication number
US3198219A
US3198219A US16918762A US3198219A US 3198219 A US3198219 A US 3198219A US 16918762 A US16918762 A US 16918762A US 3198219 A US3198219 A US 3198219A
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United States
Prior art keywords
struts
bending
metal members
boom
bell
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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Inventor
Grebner Fritz
Koelsch Willelm
Lauterbach Willi
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RHEINBAN GmbH
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RHEINBAN GmbH
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Priority to DER29552A priority Critical patent/DE1166734B/en
Application filed by RHEINBAN GmbH filed Critical RHEINBAN GmbH
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Publication of US3198219A publication Critical patent/US3198219A/en
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    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04CSTRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/01Reinforcing elements of metal, e.g. with non-structural coatings
    • E04C5/06Reinforcing elements of metal, e.g. with non-structural coatings of high bending resistance, i.e. of essentially three-dimensional extent, e.g. lattice girders
    • E04C5/065Light-weight girders, e.g. with precast parts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21FWORKING OR PROCESSING OF METAL WIRE
    • B21F27/00Making wire network, i.e. wire nets
    • B21F27/12Making special types or portions of network by methods or means specially adapted therefor
    • B21F27/20Making special types or portions of network by methods or means specially adapted therefor of plaster-carrying network
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K11/00Resistance welding; Severing by resistance heating
    • B23K11/002Resistance welding; Severing by resistance heating specially adapted for particular articles or work
    • B23K11/008Manufacturing of metallic grids or mats by spot welding

Description

Aug. 3, 1965 F. GREBNER ETAL 3,198,219

APPARATUS FOR PRODUCING A GIRDER Filed Jan. 25, 1962 3 Sheets-Sheet 1 By WILHELM (055 Aug. 3, 1965 F. GREBNER ETAL APPARATUS FOR PRODUCING A GIRDER 3 Sheets-Sheet 2 Filed Jan. 25, 1962 mm 8 mm mm Inventors, Ffl/Tz, GK: z/vrR.

1965 F. GREBNER ETAL 3,198,219

APPARATUS FOR PRODUCING A GIRDER Filed Jan. 25, 1962 3 Sheets-Sheet 3 Ilse Hf United States Patent 3,198,219 APPARATUS FGR PRODUCING A GERBER Fritz Grebner, Mainz, Wiihelm Koelsch, Wiesbaden, and Wiili Lauterhacl Hechtsheim, Germany, assignors to Rheinban Grub-IL, Wiesbaden, Germany, a German company Fiied .ian. 25, 1962, Ser. No. 169,187 Claims priority, applimtion Germany, Jan. 27, W61, R 29,552 Claims. -Cl. 140-112) The invention relates to an apparatus for the continuous production of lattice girders, or reinforcements of the lattice girder type, for ferroconcrete ceilings, floors and the like.

Various apparatus exist for the production of girder reinforcing elements, but these provide a low output in comparison to the outlay which they require. They operate by drawing off structural steel wires, which are to form the girder, from reels and then bending the wires which are subsequently connected to one another by spotwelding.

The bending method normally employed includes bending dies composed of a bending punch and a matrix, but with these dies it is only possible to bend one Wire corrugation, between each of two advancing phases, since after the bending of each corrugation in the wire, further wire material must be drawn off the reels before the next corrugation can be formed. This takes up a good deal of time, and a low output results.

In accordance with the invention, spaced portions of the wires are raised or depressed simultaneously or in immediate succession whilst holding intervening portions, so as to bend the wires into a corrugated or undulating shape, the portions being raised or lowered being caused to approach the fixed portions during the bending and then welding the bent Wire along the tops or bottoms of the undulations to a straight boom wire.

Such a method allows a substantial increase in the output per unit of time without requiring any greater mechanical outlay. According to the invention, in each working phase occurring between the advancing phases, a plurality of corrugations are both bent and welded to the wire which is used as a longitudinal boom and which is fed simultaneously with the wires to be corrugated. Any desired number of corrugations can be bent between two advancing phases, the only deciding factor being the length to which the machine can be built or used. Within one working phase, the bending is carried out in such a manner that the corrugations are bent stepwise immediately after one another, there being provided a plurality of bending angles which are displaceable in the direction of advance and are pivotable about axes situated transversely thereto, and which are connected to one another by links connected to one arm of the angles,

whilst the other arms are coupled to a driving device. This method makes it possible within each advancing phase to draw off from the reels as much wire as is necessary for the bending of two, four, five, etc. corrugations. After the conclusion of each advancing phase, the working phase begins in which, as already mentioned, the various corrugations are formed stepwise one after the other.

The invention is concerned with apparatus for carrying out the method and comprising a wire bending device having means for holdingspaced portions of the wire, bending means for raising or lowering the intermediate portions either simultaneously or in immediate succession so that the wire can be bent into a number of corrugations or undulations between two advancing stages.

In order to produce reinforcing elements of the lattice girder type, both wires necessary for this purpose can be (nil bent simultaneously by two bending devices of the kind already described to be arranged side by side and at an inclination relatively to one another.

The movement of the bending angles of the bending apparatus can be effected by a common drive apparatus, the corresponding arms of adjacent angle members being connected together by links which are in each case connected fixedly to one limb and by means of a guide slot to the other limb, whilst a drive apparatus, for example a pneumatic cylinder, is connected to the forward or rearward end.

An embodiment of the invention will now be described, by way of example with reference to the accompanying drawings in which:

FIGURES la and lb are diagrammatic side views of an apparatus in accordance with the invention;

FIGURES 2a and 2b are diagrammatic plan views;

FIGURE 3 is a section through the apparatus taken on the line III-III in FIGURE la;

FIGURE 4 is a section through the apparatus taken on the line IVIV of FIGURE la;

FIGURE 5 is a perspective view of a reinforcement element produced by the apparatus shown in FIGURES l to 5.

The apparatus is mounted on a frame 1. Situated at one end are the wire reels 2, 3 and 4, constituting a suppiy from which structural steel wires 5, 6 and 7 are drawn off, the three lengths of elongated metal members forming the longitudinal boom and the two diagonally arranged undulating struts.

The wire reels are followed by a guide means constituted by three sets of guide rings 8, 9 and 10, of decreasing diameter in the direction of advance ill to roughly align the Wires 5 to '7. The wire is then drawn through an orifice plate 13 provided with three orifices 12 (see FIGURE 3), which are arranged so as to further align the wires before they pass into the bending station. After the orifice plate, the fine alignment of the wires 5 to 7 is eifected by three sets 14, i5 and 16 of guide pulleys which are arranged so that each set has its axes at right angles to the adjacent set. In some cases it is expedient to arrange immediately after these sets of pulleys, at about the point 17, a feed device, for example a clampingvise, whereby the three wires 5 to 7 are engaged and moved in the direction of advance 11. For the sake of easy reading of the drawings, this feed device has not been illustrated.

The three aligned wires 5 to 7 then run .into the bending station which is illustrated in detail in the sectional view shown ill FIGURE 4. As shown, the device comprises four bending arms 18, 19, 2t} and 21, which are pivotable about inclined pivots Z2 and are connected together by the links 23. The pivots 22 are mounted in lugs 24 which are fixed on sleeves 25 slidably mounted on rods 2-6 arranged at both sides. The slide rods are fixed on the machine frame 1 by bearings not shown in the drawings.

The upper wire 5 which issues from the last set of pulleys l6 and is used for forming the longitudinal boom, travels straight through the bending device since it is not to be bent. The two other wires 6 and 7, which are used for forming the diagonals, are guided over the pivots 22 of the bending arms of two halves of the bending device located at an angle to one another. The wires are guided in the longitudinal direction between two successive bending arms on pulleys 27 which are mounted on shafts 28 which connect the ends of the upper limb of the bending arms to the links 23.

The downwardly directed limbs of the bending arms 18 to 21 are connected to one another in the longitudinal direction by links 29 which at one end are connected pivotably but non-displaceably to one arm limb and at the other end are connected pivotably and in such a manner as to be slidable in a guide slot 30, to the limb of an adjacent arm.

The forward (or rear) downwardly directed limb of bending arm 18 (or M) is acted upon by a piston rod 31 of a piston working in a pneumatic cylinder 32 which is used as a drive apparatus, and which is mounted on the machine frame 1.

In order to hold down the wire at the regions of the pivots 22 during the bending of corrugations in the wires 6 and 7, engageable and disengageahle holding claws 33 are provided which, during the bending operation, hold down the Wires and thereafter release them for the advancing phase. The claws are connected to a connecting rod 34 which slides in a bearing through the lugs 24 of the sleeves 25. The connecting rod is situated below the pivot 22 carrying the bending arms, the said pivot passing through an appropriate aperture 35 in the claw 33. The connecting rod 34 slides in a housing 36 and is biased, by a spring 3% acting on a collar 37 on the rod, to a position in which the claws 33 hold down the wires 6 and 7. In order to release the wires, the claws 33 are moved towards one another in the direction of the arrows 33, by means of a control bar 39 which is mounted on the machine frame andwhose control surface 48! abuts with an extension 41 of the connecting rod 34. The control bar 39 is mounted to be movable to and fro on the machine frame 1 by links 42 (FIGURE 2a) and is connected to a piston rod 43 of a piston working in a cylinder 44.

The bending device is followed by spot-welding devices 45 which are constructed in a conventional manner and are only outlined in the drawings. The devices 45 weld the bent wire corrugations at their uppermost portion into the wire forming the longitudinal boom, so as to form a reinforcing element as shown in FlG. 5.

A feed device is also arranged downstream of the bending device in the direction of advance to feed either the bent wire corrugations, or these together with the longitudinal wire 5 welded thereto. For this purpose, a support which is constructed as a rod e7 or the like is mounted in bearings to on the machine frame 1 and is connected at one end to a piston rod 43 connected .toa piston working in a cylinder 49 and used as a drive apparatus. For example in the region of the welding device (FIG- URES 1b and 212), there are situated on the support, up

I ward-1y directed supporting elements 5%) which carry a bar 51 substantially in the central region of the wire corrugations on which, in the region of each corrugation, two pivotable push rods 53 are mounted (see FIGURE 2b). The rods 53 are held in the horizontal open position by springs 52 and in this position have their forward free ends abutting against the diagonals or wirecorrugations, so that a feeding action can be provided,

Situated at the end of the machine is a table 54 which receives the finished elements. At the end of the table 'there is arranged an abutment 55 with a relay 56 arranged so that when a fed-in reinforcing element abuts the relay a cutting device 57, located at the beginning of the table 54 is tripped. The abutment 55 is conveniently arranged to be adjustable in the longitudinal direction so that various lengths can be cut. Provision is made for simultaneously rendering the feed device inoperative during the period of the cutting operation.

During operation, the wire is first located in the bending device in an extended state and is held down by the claws 33 in the region of the pivots 22. The cylinder 32 now begins to operate and the bending arm 18 is pivoted in the direction of the arrow 58, during which movement the end of its downwardly directed lim=b slides in the slot 3t) of the link 29 whilst the end connected to the link 23 is raised, thus lifting the pin 28 and pulley 27 over which the wire is guided. In this operation the wire corrugation is bent. The bending arm 13, which is controlled by the connected link 23, is advanced together with the sleeve which slides in, the advancing direction on the rod 26.

Meanwhile, the end of the downwardly directed limb of the arm 18 has arrived at the right-hand end of the slot 3d in the drawings, so that during the further movement of rod 31 the next bending arm 19 will be operated in a similar fashion and the second wire corrugation will be produced. Likewise the bending arms 26 and 21 are moved subsequently and, consequently, the third and fourth wire corrugations are produced. Thus, all the corrugations are produced in one advancing operation and the claws 33 are then released.

After the corrugations have been bent, the advancing phase begins by the operation of the cylinder 49 which moves the support 47 and, therefore, the bar 51 in the advancing direction. During this movement, the push rods 53 situated in the opened position move the two wire corrugations onwards by the proposed distance. When the advancing phase is ended, the support 47 returns to its initial position and during this movement the push rods 53 slide past the diagonals or the bent wire corrugations, with compression of the springs 52. The corrugations are spot welded to the longitudinal wire or boom.

The reinforcing element produced on the machine and shown in FIG. 5 comprises the longitudinal bar 5 made of structural steel, to which there have been welded laterally the structural steel bars 6 and 7 which are bent to an undulatory or corrugated shape and which are at an acute angle to each other,

We claim:

1. An apparatus for continuously producing a concrete reinforcing girder having a straight longitudinal boom and two undulating struts connected to the boom at an acute angle to each other, the boom .and the struts consisting of elongated metal members, comprising (a) a supply of three lengths of said elongated metal members,

( b) guide means directing the metal members from the supply to a bending station, the guide means being arranged to direct one of the metal members constituting the straight boom centrally between a pair of said metal members constituting the struts and in a plane spaced from the struts,

(0) means for feeding the metal members to, and

through, the bending station,

(d) bending means at the bending station for bending the struts into undulating configuration, the bending means including (1) a plurality of successive bell-crank levers associated with each of the struts, each of said bellcrank levers having two limbs,

(2) a pivot extending transversely of the direction of movement of said metal members mounting each of said bell-crank levers for pivoting and the limbs extending from the pivot at an angle to each other,

(3) means for displacing the pivots in said direction,

(4) rods linking an end one of the limbs of each bell-crank lever to the pivot of a successive one of said levers,

(5) a link interconnecting the ends of the other limbs of said bell-crank levers, said other limb ends being movable in successive slots in said link,

(6) means for pushing successive ones of said other limb ends in said successive slots in said direction, and

(7) means for holding intermediate portions of the struts at said pivots during pivoting of the bell crank levers,

(e) means for advancing the straight boom and the undulating struts to a welding Zone, and

(f) welding means in said zone for welding successive apices of the undulating struts to the straight boom.

2. The apparatus of claim 1, wherein said bell-crank 5 6 levers and holding means are arranged in successive pairs the pushing means and the struts holding means being and are disposed at an acute angle to each other. actuatable successively between two feeding steps.

3. The apparatus of claim 1, wherein said holding means consists of a claw member associated with each References Clted by the Exammer pivotal hell-crank lever and further comprising 5 UNITED STATES PATENTS (i) means for releasing the claws from holding engagement with the struts afiter pivoting or" the asso- 221 25? ciated bell-crank lever to permit the struts to be ad- 2645930 7/53 Stocktog vanced longitudinally before a further bending op 27O2576 2/55 Eidal 153 20 eration. 1O 4. The apparatus of claim 3, further comprising 32 3 1 3 (1') spring means holding each claw in strut engaging position and FOREIGN PATENTS (k) a common drive for releasing the claws from the 289,515 4/25 Great Britain engaging position. 15 5. The apparatus of claim 1, wherein said metal mem- RLE LA HA primary Examiner. her feeding means is arranged to feed the metal memhers, intermittently to, and through, the bending station, WILLIAM MUSHAKE Examiner

Claims (1)

1. AN APPARATUS FOR CONTINUOUSLY PRODUCING A CONCRETE REINFORCING GIRDER HAVING A STRAIGHT LONGITUDINAL BOOM AND TWO UNDULATING STRUTS CONNECTED TO THE BOOM AT AN ACUTE ANGLE TO EACH OTHER, THE BOOM AND THE STRUTS CONSISTING OF ELONGATED METAL MEMBERS, COMPRISING (A) A SUPPLY OF THREE LENGTHS OF SAID ELONGATED METAL MEMBERS, (B) GUIDE MEANS DIRECTING THE METAL MEMBERS FROM THE SUPPLY TO A BENDING STATION, THE GUIDE MEANS BEING ARRANGED TO DIRECT ONE OF THE METAL MEMBERS CONSTITUTING THE STRAIGHT BOOM CENTRALLY BETWEEN A PAIR OF SAID METAL MEMBERS CONSTITUTING THE STRUTS AND IN A PLANE SPACED FROM THE STRUTS, (C) MEANS FOR FEEDING THE METAL MEMBERS TO, AND THROUGH, THE BENDING STATION, (D) BENDING MEANS AT THE BENDING STATION FOR BENDING THE STRUTS INTO UNDULATING CONFIGURATION, THE BENDING MEANS INCLUDING (1) A PLURALITY OF SUCCESSIVE BELL-CRANK LEVERS ASSOCCIATED WITH EACH OF THE STRUTS, EACH OF SAID BELLCRANK LEVERS HAVING TWO LIMBS, (2) A PIVOT EXTENDING TRANSVERSELY OF THE DIRECTION OF MOVEMENT OF SAID METAL MEMBERS MOUNTING EACH OF SAID BELL-CRANK LEVERS FOR PIV OTING AND THE LIMBS EXTENDING FROM THE PIVOT AT AN ANGLE TO EACH OTHER, (3) MEANS FOR DISPLACING THE PIVOTS IN SAID DIRECTION, (4) RODS LINKING AN END ONE OF THE LIMBS OF EACH BELL-CRANK LEVER TO THE PIVOT OF A SUCCESSIVE ONE OF SAID LEVERS, (5) A LINK INTERCONNECTING THE ENDS OF THE OTHER LIMBS OF SAID BELL-CRANK LEVERS, SAID OTHER LIMB ENDS BEING MOVABLE IN SUCCESSIVE SLOTS IN SAID LINK (6) MEANS FOR PUSHING SUCCESSIVE ONE OF SAID OTHER LIMB ENDS IN SAID SUCCESSIVE SLOTS IN SAID DIRECTION, AND (7) MEANS FOR HOLDING INTERMEDIATE PORTIONS OF THE STRUTS AT SAID PIVOTS DURING PIVOTING OF THE BELL CRANK LEVERS, (E) MEANS FOR ADVANCING THE STRAIGHT BOOM AND THE UNDULATING STRUTS TO A WELDING ZONE, AND (F) WELDING STRUTS TO A WELDING ZONE, AND APICES OF THE UNDULATING STRUTS TO THE STRAIGHT BOOM.
US16918762 1961-01-27 1962-01-25 Apparatus for producing a girder Expired - Lifetime US3198219A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DER29552A DE1166734B (en) 1961-01-27 1961-01-27 Means for forming the grid coils of wire in a zig-zag shape

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3310075A (en) * 1964-11-23 1967-03-21 Larkin Sam Automatic machines for forming an intermediate zig-zag wire and welding it to outer parallel wires

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5346373B2 (en) * 1975-10-30 1978-12-13
JPS5346372B2 (en) * 1975-10-30 1978-12-13
GB2346575B (en) * 1999-02-10 2003-05-14 Structherm Ltd Truss machine

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1357018A (en) * 1919-03-27 1920-10-26 Albinson Alvin Plaster gage and reinforcement
GB289515A (en) * 1927-01-25 1928-04-25 Wilhelm Weber Improvements in ferro-concrete building constructions
US2645930A (en) * 1948-07-26 1953-07-21 Ray F Stockton Wire Products C Self-furring corner lath
US2698642A (en) * 1952-09-23 1955-01-04 Malina Frank Metal strip bending machine
US2702576A (en) * 1953-10-12 1955-02-22 Eidal Mfg Company Rod bending machine
US2722242A (en) * 1951-10-26 1955-11-01 Cedar Rapids Block Co Wire forming apparatus
US2844024A (en) * 1954-10-21 1958-07-22 Mcdonald James Leonard Combination preformed and cast-in-situ reinforced flooring structure

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR867035A (en) * 1940-05-24 1941-09-23 Folding machine and chevronner bars
US2661787A (en) * 1952-04-03 1953-12-08 Roy M Eidal Rod bending machine
AT195222B (en) * 1954-03-16 1958-01-25 Stefan Dipl Ing Keller A process for the production of lattice girders, in particular floor beams for buildings and produced thereby girder-forms, as well as apparatus for carrying out the method
US2815062A (en) * 1956-03-09 1957-12-03 John A Cook Machine to simultaneously effect a plurality of bends in a rod

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1357018A (en) * 1919-03-27 1920-10-26 Albinson Alvin Plaster gage and reinforcement
GB289515A (en) * 1927-01-25 1928-04-25 Wilhelm Weber Improvements in ferro-concrete building constructions
US2645930A (en) * 1948-07-26 1953-07-21 Ray F Stockton Wire Products C Self-furring corner lath
US2722242A (en) * 1951-10-26 1955-11-01 Cedar Rapids Block Co Wire forming apparatus
US2698642A (en) * 1952-09-23 1955-01-04 Malina Frank Metal strip bending machine
US2702576A (en) * 1953-10-12 1955-02-22 Eidal Mfg Company Rod bending machine
US2844024A (en) * 1954-10-21 1958-07-22 Mcdonald James Leonard Combination preformed and cast-in-situ reinforced flooring structure

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3310075A (en) * 1964-11-23 1967-03-21 Larkin Sam Automatic machines for forming an intermediate zig-zag wire and welding it to outer parallel wires

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GB994989A (en) 1965-06-10
DE1166734B (en) 1964-04-02

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