MACHINE AND METHOD FOR PRODUCING SIMPLY REINFORCED STEEL WIRE MESHES

Abstract

The present invention relates to a machine and to a method for producing uniaxial reinforcing steel bar meshes, in particular for uses with not predominantly static load, wherein reinforcing wires are fastened to support strips by means of individual wire tying.

Claims

1. A machine for producing uniaxial reinforcing steel bar meshes, having a steel strip conveyor (1) for conveying a plurality of support strips (2) which are parallel to one another and spaced apart from one another, and a reinforcing bar conveyor (3), wherein the reinforcing bar conveyor (3) conveys individual reinforcing bars (4) in a crossing manner onto the plurality of support strips (2), forming crossing points (5), and also positions them in a longitudinal-axial manner with respect thereto, and a plurality of connecting units (6) operatively arranged at each crossing point (5), wherein a connecting unit (6) has a binding wire conveyer (7) feeding a binding wire (8) through a rotating unit (9), wherein the rotating unit (9) is movable relative to the support strip (2) and the crossing reinforcing bar (4) and is arranged on a side of the plane defined by the support strip (2) and the reinforcing bar (4), wherein the connecting unit (6) further has a binding wire guide unit (10) which is arranged on the opposite side of the plane and which frictionally feeds out and holds a binding wire (8) fed thereinto by the binding wire conveyer (7) in a direction reverse to the infeed direction, wherein the rotating unit (9) twists the two binding wire strands (11) located on a side of the plane together and cuts them to length, characterized in that the rotating unit (9) and the binding wire guide unit (10) are moved towards each other in a closing manner to form a wire loop connecting the support strip (2) and the reinforcing bar (4) in such a manner that the support strip (2) and the reinforcing bar (4) are pressed against each other.

2. The machine according to claim 1, wherein the rotating unit (9) comprises a cutoff device (12), in particular a knife (13).

3. The machine according to claim 1, characterized in that the machine bends a cut-to-length wire binding between the support strip (2) and the crossing reinforcing bar (4), produced by the machine, from a predominantly orthogonal orientation to the plane to a predominantly parallel orientation to the plane.

4. The machine according to claim 1, wherein the guides (14) are openings (15) and/or recesses, wherein the machine creates these guides (14) in-situ.

5. The machine according to claim 1, wherein the openings (15) are formed as elongated holes (17).

6. The machine according to claim 1, wherein an edge distance (A) between two guides (14) is selected depending on the diameter of the respective reinforcing steel bar (4) to be connected, in that the edge distance (A) is smaller than a diameter (D) of the reinforcing steel bar (4) to be fastened.

7. The machine according to claim 1, wherein a length (L) of the binding wire (8) required for connection is varied depending on the diameter of the respective reinforcing steel bar (4) to be connected.

8. A method for producing a uniaxial reinforcing bar mesh from a plurality of reinforcing bars which are parallel to each other and spaced apart from each other and are orthogonally oriented to and fastened to a plurality of support strips which are parallel to each other and spaced apart from each other, comprising the following steps: a) feeding a reinforcing bar orthogonally to the longitudinal axes of parallel support strips which are spaced apart from each other to create a plurality of crossing points between the respective steel strip and reinforcing bar, b) pressing the reinforcing bar onto the support strip to hold it in close position, c) feeding a binding wire in the region of a crossing point around the steel strip and the reinforcing bar thereby forming a double binding wire strand on one side, d) cutting the binding wire to length and twisting the two binding wire strands thus created to form a twisting section.

9. The method according to claim 8, wherein after step d), a step e) of bending the twisting section in or towards the plane defined by support strips and reinforcing bars is carried out.

10. The method according to claim 8, wherein step b) of pressing the reinforcing bar onto the support strip is carried out before, during, or after steps c) and/or d).

11. The method according to claim 8, wherein step d) comprises bending the second free end of the binding wire created by cutting to length.

12. The method according to claim 8, wherein a step f) of inserting guides into the support strip is carried out.

Description

[0026] The invention is explained in more detail below with reference to the figures of an exemplary embodiment, wherein the same components are designated by the same reference signs. In the figures

[0027] FIG. 1: shows a schematic view of a wire loop,

[0028] FIG. 2: shows a schematic sectional view of an embodiment of the machine in a first state, and

[0029] FIG. 3: shows a schematic sectional view of an embodiment of the machine in a second state.

[0030] FIG. 1 shows a binding wire loop according to the invention around a crossing point 5 of a support strip 2—here a flat, flexible steel strip—and a reinforcing bar 4—here a bar made of a reinforcing steel. Elongated holes 17, the closest edge distance A between which is smaller than a diameter D of the reinforcing bar 4, can be seen in the support strip 2. Here, the two elongated holes 17 are an embodiment of the guide 14 according to the invention of the binding wire 8 in the form of openings 15. The binding wire 8 is guided through the two elongated holes 17 and the two binding wire strands 11 are twisted to form a twisting section 18 after the method according to the invention has been carried out, wherein, according to the invention, this twisting section 18 is also bent, in particular approximately parallel to the plane of the support strip 2 and reinforcing bar 4, in order to prevent it from protruding from the concrete at a later time and also to prevent injuries to a user. In this context, plane is not to be understood to mean a strictly mathematical two-dimensional plane, but rather the three-dimensional plane formed by support strip 2 and reinforcing bar 4. The width of the support strips 2 of a uniaxial reinforcing mesh is selected such that it can be rolled out with safe straight-line stability.

[0031] According to the invention, the reinforcing bars 4 are selected from those with diameters between 6 mm and 40 mm, wherein the distances between the parallel reinforcing bars 4 of a uniaxial reinforcing mesh can be freely selected in accordance with the requirements of the respective use of the uniaxial reinforcing mesh. This is done by computer-controlled optimized planning with regard to length, position, distance, diameter, material, etc.. Preferably, a minimum distance is maintained between two adjacent reinforcing bars 4 in order to achieve a transfer safety.

[0032] The edge distance A of the web of the support strip 2 remaining between the elongated holes 17 is adapted to the bar diameter D to be bound. In particular, it is smaller or has the same width as the latter. This ensures that the binding does not become loose even if the support strip 2 is bent or kinked, especially during coiling in production. By adapting the size of the edge distance A, a tight binding is always achieved for any different diameters D of the reinforcing bars 4. It also prevents twisting of the reinforcing bar 4 about its longitudinal axis. According to the invention, this distance A is also selected to be wider than the bar diameter D. This results in a kind of clutching of the reinforcing bar 4 with positive effects on position stabilization while at the same time providing a firm binding.

[0033] FIG. 2 shows an embodiment of the invention in a first operating state. In this operating state, a reinforcing bar 4 has already been fed onto a plurality of support strips 2 and, where necessary, positioned with respect thereto in its axial direction. The support strip conveyer 1 and the reinforcing rod conveyer 3 are shown purely schematically, and the crossing point 5 is located below the reinforcing bar 4 shown, wherein the rounded binding wire guide unit 10 is arranged below the crossing point 5 and preferably partially engages around the support strip 2 and the reinforcing bar 4. A binding wire conveying unit 7 is shown schematically. It conveys the binding wire 8 through the rotating unit 9 in the direction of the crossing point 5. The connecting unit 6 according to the invention consists of the components of the binding wire conveyer 7, the rotating unit 9 and the binding wire guide unit 10. The rotating unit 9 has a U-shaped body through which the binding wire 8 is guided.

[0034] In this embodiment, the support strip 2 is guided by a schematically shown punching unit 19 which provides in-situ guides 14 in the form of elongated holes 17 in the support strip 2. According to the invention, the guides 14 can also be, for example, triangular or dovetail-like recesses in the edge regions of the support strip 2, in particular recesses offset relative to one another diagonal to the longitudinal axis of the support strip 2 or openings 15 shaped differently from elongated holes. Alternatively, a support strip 2 already provided with guides 14 during manufacture is used according to the invention.

[0035] The operating state shown is the one before the connection. In order to create the wire loop, the rotating unit 9 and the reinforcing wire guide unit 10 are moved in a closing manner towards each other so that the binding wire 8 is fed into the wire guide unit 10 below the intersection point 5 of the support strip 2 and the reinforcing bar 4 without a gap and is then fed out again there in the opposite direction to the feed direction, wherein a specific projection length is selected depending on the diameter D of the bar 4 to be fastened after it has been fed out.

[0036] FIG. 3 shows a second operating state in which the connection is made by creating a tightened wire loop. The rotating unit 9 is raised above the bar cross-section. Here, as seen in the conveying direction of the binding wire 8, the binding wire is cut off by means of a knife 13 as a cutoff device 12 before the rotating unit 9, and the second free wire end thus created, preferably due to the shaping of the knife 13, is simultaneously bent by the latter, preferably in the direction of the reinforcing bar 2. During the rotation of the rotating unit 9, this bent end causes a pulling-out resistance against pulling out due to the shortening of the projecting wire length resulting from the twisting. This makes the binding tight and firm. The rotation against the pull-out resistance allows the two binding wire strands 11 to be twisted against each other, creating a twisting section 18. The rotation ultimately causes the bent end to slip out of the rotating unit 9. After the firm hold is released, the bar is now free. During binding, the bar and the strip are additionally pressed onto each other according to the invention and thus held in a tight position.

[0037] When the bar is transported further, the twisting section 18 is also kinked so as not to protrude too far. The binding could otherwise protrude from the concrete in the upper position or also cause injuries.

REFERENCE LIST

[0038] 1 support strip conveyor [0039] 2 support strip [0040] 3 reinforcing bar conveyor [0041] 4 reinforcing bar [0042] 5 crossing point [0043] 6 connecting unit [0044] 7 binding wire conveyor [0045] 8 binding wire [0046] 9 rotating unit [0047] 10 binding wire guide unit [0048] 11 binding wire strand [0049] 12 cutoff device [0050] 13 knife [0051] 14 guide [0052] 15 opening [0053] 16 [0054] 17 elongated hole [0055] 18 twisting section [0056] 19 punching unit [0057] 20 binding wire channel [0058] A edge distance [0059] D diameter