Machine and method for producing simply reinforced steel wire meshes

Abstract

A machine and a method for producing uniaxial reinforcing steel bar meshes, in particular for uses with not predominantly static load, has reinforcing wires which are fastened to support strips by individual wire tying.

Claims

1. A machine for producing uniaxial reinforcing steel bar meshes, the machine comprising: a steel strip conveyor (1) for conveying a plurality of support strips (2), the plurality of support strips (2) being parallel to one another and spaced apart from one another; and a reinforcing bar conveyor (3), wherein the reinforcing bar conveyor (3) is configured to convey individual reinforcing bars (4) in a crossing manner onto the plurality of support strips (2), forming a crossing point (5) at each position where each of the individual reinforcing bars (4) crosses each one of the plurality support strips (2); and a plurality of connecting units (6) operatively arranged at each crossing point (5), wherein each of the plurality of connecting units (6) has a binding wire conveyer (7) configured to feed a binding wire (8) through a rotating unit (9), wherein the rotating unit (9) is configured to be movable relative to each of the plurality of support strips (2) and each of the individual reinforcing bars (4), wherein the rotating unit is arranged on a side of a plane defined by each of the plurality of support strips (2) and each of the individual reinforcing bars (4), wherein each of the plurality of connecting units (6) further has a binding wire guide unit (10), wherein the binding wire guide unit (10) is arranged on an opposite side of the plane, and wherein the binding wire guide unit (10) is configured to frictionally feed out and hold the binding wire (8) fed thereinto by the binding wire conveyer (7) in a direction reverse to an infeed direction, wherein the rotating unit (9) is configured to twist two binding wire strands (11) located on the side of the plane together and cut the two binding wire strands (11) to length, wherein the rotating unit (9) and the binding wire guide unit (10) are configured to move towards each other in a closing manner to form a wire loop connecting each of the plurality of support strips (2) and each of the individual reinforcing bars (4) in such a manner that each of the plurality of support strips (2) and each of the individual reinforcing bars (4) are pressed against each other.

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

3. The machine according to claim 1, wherein the rotating unit (9) is configured to bend the two binding wire strands (11) between each of the plurality of support strips (2) and each of the individual reinforcing bars (4) from a predominantly orthogonal orientation to the plane to a predominantly parallel orientation to the plane.

4. The machine according to claim 1, wherein each of the plurality of support strips (2) comprises the guides (14), wherein the guides (14) are openings (15) in each of the plurality of support strips (2), and further comprising a punching unit (19) configured to provide the guides (14) in-situ in each of the plurality of support strips (2).

5. The machine according to claim 4, wherein the punching unit (19) is configured to form the openings (15) as elongated holes (17).

6. The machine according to claim 4, wherein the individual reinforcing bars (4) to be connected have a predetermined diameter, wherein an edge distance (A) between two adjacent guides (14) is selected based on the predetermined diameter of the individual reinforcing bars (4) to be connected, wherein the edge distance (A) is smaller than the predetermined diameter (D) of the individual reinforcing bars (4) to be fastened.

7. The machine according to claim 6, wherein a length (L) of the binding wire (8) required for connection is varied depending on the predetermined diameter of the individual reinforcing bars (4) to be connected.

Description

(1) 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

(2) FIG. 1: shows a schematic view of a wire loop,

(3) FIG. 2: shows a schematic sectional view of an embodiment of the machine in a first state, and

(4) FIG. 3: shows a schematic sectional view of an embodiment of the machine in a second state.

(5) FIG. 1 shows a binding wire loop according to the invention around a crossing point 5 of a support strip 2here a flat, flexible steel stripand a reinforcing bar 4here 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.

(6) 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.

(7) 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.

(8) 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.

(9) 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.

(10) 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.

(11) 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.

(12) 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

(13) 1 support strip conveyor 2 support strip 3 reinforcing bar conveyor 4 reinforcing bar 5 crossing point 6 connecting unit 7 binding wire conveyor 8 binding wire 9 rotating unit 10 binding wire guide unit 11 binding wire strand 12 cutoff device 13 knife 14 guide 15 opening 16 17 elongated hole 18 twisting section 19 punching unit 20 binding wire channel A edge distance D diameter