Cross wire feed device and method for wire mesh welding machine

Abstract

The present invention relates to a device for feeding cross wires (1) up and down a production line for a mesh mat (3) consisting of welded cross and longitudinal wires, the device comprising an upper cross wire feeder having a guideway (5) and arranged at a first position in which the cross wire is fed along the guideway of the production line, and a lower cross wire feeder (7) capable of transporting the cross wire to the production line from below, the device being provided with a lower cross wire storage section (8) from which the cross wire can be taken out by the lower cross wire feeder, the upper cross wire feeder being designed as a cross wire exchanger (4) that can be pivoted to at least a second position, by means of which the cross wire exchanger in the second position can load the cross wire into the lower cross wire storage section.

Description

[Technical Field]

[0001] The present invention relates to an apparatus for feeding cross wires up and down a production line for a mesh mat consisting of welded cloth and vertical wires, the apparatus comprising an upper cross wire feeder having a guideway and positioned at a first position where the cross wires are fed along the guideway of the production line, and a lower cross wire feeder capable of transporting the cross wires to the production line from below. The present invention also relates to a method for feeding cross wires to a production line for a mesh mat having upper and lower cross wires that can be welded to a set of vertical wires, the method comprising the following repeated series of steps: (i) removing cross wires from a magazine in the guideway of the upper cross wire feeder positioned above the production line; (ii) feeding the cross wires obtained in step (i) to the set of vertical wires, removing cross wires from a cross wire storage device similarly positioned below the production line, and feeding the cross wires obtained in the previous step to the set of vertical wires. [Background technology]

[0002] Business and private property is often restricted to prevent unwanted trespassing on the property. This can be done in a variety of ways, but restriction by fences made of steel wire consisting of fence mats has proven to be the most economical.

[0003] Various fence mat variations can be designed such that the cross wires are exactly above or below the longitudinal wires, the / each cross wire is longitudinally offset above or below, each pair of longitudinal wires is placed above and each pair of cross wires is placed below the longitudinal wires, the fence mat is welded to the cross wires above the longitudinal wires or only to the cross wires below them.

[0004] A series of fence mats with cross wires above the longitudinal wires and cross wires below the longitudinal wires can reduce the stack height by approximately half.

[0005] It is prior art for fence mats, such as "double rod fence mats," to be manufactured from double rods placed transverse to the direction of manufacture; that is, one cross wire above the longitudinal wires and one cross wire below. During manufacture of the fence mat, the opposing cross wires to be welded to the double rod fence mat are welded in place in a welding machine. It is also prior art for fence mats to be manufactured from pre-cut longitudinal wires in small quantities.

[0006] One problem with the prior art is that the construction of fence mats requires welding many more longitudinal wires than cross wires, which can result in downtime in the production of individual fence mats. For example, for a standard double-rod fence mat with dimensions of 3 x 2 m, the time ratio between preparing the longitudinal wires and producing the fence mat can be up to 2:1.

[0007] In the past, the pre-cut cross wire required for production was supplied to the welding machine from a cross wire magazine that was either separate from the cross wire bundle or fed by an in-line wire straightening system.

[0008] To be able to manufacture these double rod fence mats, and in turn fence mesh mats with cross wires above or below the vertical wires, two cross wire magazines are nowadays arranged, one above the production line and one below or below and to the side of the production line.

[0009] Disadvantages of the variant with a cross wire magazine below the production line are the breaking of the cross wires and the filling, maintenance and troubleshooting of the cross wire supply.

[0010] The disadvantages of the variant with the cross wire magazine below and beside the production line are that additional space is required and that additional equipment is needed for transport to the welding line. To ensure production at the appropriate speed and positional accuracy, the system must be equipped with complex electric drive technology. Another disadvantage is that the two cross wire magazines must be modified whenever the cross wire diameter and cross wire length change. In summary, the disadvantages of the aforementioned cross wire variant are the investment, maintenance and installation costs. Summary of the Invention

[0011] The object of the present invention is therefore to avoid the aforementioned disadvantages, which is achieved by the device according to the invention in that a lower cross wire storage device is provided from which cross wires can be taken up by a lower cross wire feeder, and the upper cross wire feeder is designed as a cross wire exchanger which can be pivoted to at least one second position in which cross wires can be fed to the lower cross wire storage device by means of the cross wire exchanger.

[0012] According to the method of the present invention, the following steps are carried out after step (ii) and before the subsequent steps, thereby eliminating the disadvantages of the prior art.

[0013] (iii) removing further cross wires from the magazine and placing them in the guideways of the upper cross wire feeder and pivoting the cross wire feeder, which is designed as a cross wire exchanger, to a second position;

[0014] (iv) feeding the cross wires obtained in step (iii) to a temporary stop position of the lower cross wire storage device;

[0015] (v) pivoting the cross wire exchanger back to the first position;

[0016] Further features of the system and method according to the invention can be found in the dependent claims.

[0017] The invention is explained in more detail below using embodiments shown in the drawings. [Brief explanation of the drawings]

[0018] [Figure 1] A schematic side view of the device is shown. [Figure 2] FIG. 1 shows a schematic side view with the mesh mat omitted. [Figure 3] A schematic side view of the device is shown. DETAILED DESCRIPTION OF THE INVENTION

[0019] According to Figure 1, elements such as double-rod fence mats are produced in the form of wire mesh mats 3 by welding upper and lower cross wires 1 to a set of longitudinal wires 2. The set of longitudinal wires 2 (only one longitudinal wire 2 is visible in the side views of Figures 1 and 3) is in a production line and moves cyclically along the production direction P. The supplied cross wires 1 are stopped at a cross wire stop 12 and are welded to the longitudinal wires by an electrical resistance method using upper and lower electrodes 14 and 15.

[0020] In the case of cyclic cross wire feeding, an overhead cross wire magazine (not shown) is mounted with a wire change station 4 so that the cross wire storage device 8, or cross wire magazine, can be filled below the production line during mat production downtime. Downtime, which remains a problem in the prior art, is advantageously utilized by the present invention.

[0021] The cross wire exchanger 4 is designed so that the guideway 5 can be pivoted to two defined positions (possibly more). As shown in FIG. 1, the first position is used to feed the cross wire 1 above the production line directly to the production or welding line. In the second position of the guideway 5 (see FIG. 2), the cross wire storage device 8, i.e., the lower cross wire magazine, can be filled below the production line. In the simplest case, shown in FIGS. 1 to 3, the guideway 5 is a track on the arm of the cross wire exchanger 4, which guides the cross wire 1 to a predetermined location along the direction Q. In the first position, the exit of the guideway 5 is a predetermined location for welding the upper cross wire 1 on the cross wire stop 12, and in the second position, it is a temporary stop position on the carriage 9 of the lower cross wire storage device 7. The upper and lower cross wire feeders are configured to be able to place the cross wires in the same position (opposite the longitudinal wires 2) as viewed in the flow direction.

[0022] The cross wire exchanger 4 is mounted on a pivot pin located on an axis 6 that allows the cross wire exchanger 4 to be rotated between at least two positions. The axis 6 extends parallel to the longitudinal axis of the cross wires 1 to be processed. It should be noted that only in the design of the device can the cross wire exchanger 4 be freely pivoted between the wire mesh mat being produced and the other elements of the device.

[0023] The cross wire storage device 8 located below the production line is designed so that a sufficient number of cross wires can be individually picked up and, if necessary, further circulated and transported to the lower cross wire feeder 7. Since it is appropriate to design the production line horizontally in relation to gravity, the "upper" and "lower" areas of the production line are also positioned along and defined by the direction of gravity.

[0024] 2, the lower cross wire storage device 8 consists of a group of wire pick-up elements (e.g., carriages 9) arranged on a continuous conveying chain 10 and capable of circular movement in direction R. The storage capacity of the lower cross wire storage device 8 can be small or large, which helps to adjust manufacturing and operating costs. That is, any number of the cross wire 1 parking positions, from a few to up to about 100, can actually be occupied by the cross wire 1 during operation.

[0025] The cross wire feeder 7 located below the production line, which is used to feed the cross wire 1 to the welding line, can be designed very simply due to its short travel path. According to FIG. 3, the length of the travel path is limited only by the shortest distance between the positions of the wire pick-up elements carrying the cross wire 1, up to the welding position below the production line. In the simplest case, the cross wire feeder 7 is a fork that, using gravity and optionally simple stop means, lifts the cross wire 1 from the wire pick-up element designed as a carriage 9 and presses it against the longitudinal wire 2 from below. This short travel path also allows for very dynamic operating modes with short cycle times.

[0026] In a previous automated wire mesh welding method, a pre-prepared set of vertical wires 2, as shown in FIGS. 1 and 3, is cyclically advanced in the production direction P. Upper and lower feeders place two cross wires 1 facing the vertical wires 2 in the positions where they will be welded. The feeders previously retrieve the cross wires 1 from a cross wire magazine. For example, a repetitive process for producing a double-rod fence mat involves rotating the upper feeder, which serves as the cross wire exchanger 4, to a second position to load the lower, compactly designed cross wire storage device 8 and transfer one, two, or three cross wires to the cross wire storage device 8. The cross wire exchanger 4 then rotates back to its first position to feed the next cross wire 1 into the production line from above. The present invention utilizes the aforementioned unavoidable machine downtime between successive mat productions or welding segments. That is, the production time can also be used to load the lower cross wire storage device 8 (i.e., the wire magazine).

[0027] In one variant, the upper cross wire exchanger 4 could transfer the cross wires 1 directly to the lower cross wire feeder 7. In that case, the lower cross wire storage device 8 could be omitted entirely, i.e., this would avoid the disadvantage of no longer having a buffer stock at the lower cross wires 1. This could happen, for example, when the first pair of cross wires of a mat is being welded and the longitudinal wires have not yet extended into the path of travel of the cross wire exchanger 4.

[0028] In a further variant, the load capacity of the lower cross wire storage device 8 is large enough to hold the number of cross wires 1 of a finished mesh mat. Thus, the lower cross wire storage device 8 could be filled during the time interval between the production of two consecutive mesh mats. The advantages of the invention are also realized if the lower cross wire storage device holds the number of cross wires 1 for an entire batch of mats and is filled once before production begins for that purpose.

[0029] In a further alternative, the lower cross wire storage device 8 is moved outward from the side so as to feed the cross wires 1 next to the production line or next to the mesh mat being produced, in which case the skilled person will select established means to also deflect the cross wire exchanger 4 outward from the side accordingly.

[0030] A further advantage of the method is that it allows programming of a cyclically repeated series of steps for the production of mesh mats in conjunction with the supply of the lower cross wire storage device 8 using the cross wire exchanger 4 already within the scope of the electronic controller in use. Furthermore, this linked method step can be integrated into environments where the cross wire material is changed.

Claims

1. 1. An apparatus for feeding cross wires (1) up and down a production line for a mesh mat (3) made of welded cloth and longitudinal wires, the apparatus comprising: an upper cross wire feeder having a guideway (5) and arranged at a first position in the production line where the cross wires (1) are fed along the guideway (5) of the production line; and a lower cross wire feeder (7) capable of transporting the cross wires (1) to the production line from below, the apparatus being characterized in that a lower cross wire storage device (8) is provided from which the cross wires (1) can be taken out by the lower cross wire feeder (7), the upper cross wire feeder being designed as a cross wire exchanger (4) that can be swiveled to at least one second position, and in which the cross wire exchanger (4) can be used to supply the cross wires to the lower cross wire storage device (8) in the second position.

2. 2. The device according to claim 1, wherein the cross wire exchanger (4) is an arm that can be pivoted between the first and second positions about an axis (6) parallel to the axis of the processed cross wire (1).

3. 3. The cross wire feeding device according to claim 1, wherein in the second position, the exit of the guide path (5) of the cross wire exchange section (4) is located at a temporary stop position of the cross wire (1) in the lower cross wire storage device (8).

4. 4. An apparatus according to claim 1, wherein the lower cross wire storage device (8) comprises a wire pick-up element arranged on the continuous conveying chain (10) for picking up the cross wires (1).

5. 5. An apparatus according to any one of claims 1 to 4, characterized in that the lower cross wire feeder (7) comprises at least one fork capable of lifting separate cross wires (1) onto the production line.

6. 6. An apparatus according to claim 1, wherein the cross wire exchanger (4) is connected to a magazine for the cross wires (1) so that a separate cross wire (1) can be picked up in its guideway (5).

7. 1. A method for feeding cross wires (1) to a production line for a mesh mat (3) having upper and lower cross wires (1) weldable to a set of longitudinal wires (2), comprising: (i) removing the cross wire (1) from the magazine in the guideway (5) of the upper cross wire feeder located above the production line; (ii) feeding the cross wires (1) obtained in step (i) into the longitudinal wire set (2); (vi) a step of taking out the cross wires (1) from a lower cross wire storage device (8) arranged below the production line by a lower cross wire feeder (7) also arranged below the production line; (vii) feeding the cross wires (1) obtained in step (vi) into a set of longitudinal wires (2), After step (ii) and before step (vi), (iii) taking further cross wires (1) from the magazine and placing them in the guideways (5) of the upper cross wire feeder and pivoting the upper cross wire feeder, designed as a cross wire exchanger (4), from a first position to a second position; (iv) feeding the cross wires (1) obtained in step (iii) to a temporary stop position of the lower cross wire storage device (8); (v) a step of turning the cross wire exchange unit (4) back to the first position.

8. A method for producing a mesh mat (3), comprising the steps of the method according to claim 7, cyclically advancing the longitudinal wire set (2) in the production line; a step of welding a pair of supplied cross wires (1) to the vertical wire set (2); The cross wire feeding method further includes the steps of repeating the above.

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