WELDED METAL NETS

Field of application

The present invention relates to a machine and to the associated method for the angular movement on a surface of flat and/or three-dimensionally folded electrically welded metal nets in order to move them in the service of adapted folding machines. Said machine works in line and on the same work surface in apparatuses for forming metal nets and three-dimensional lattice- like structures, and is simple in concept but fundamental and advantageous in its usefulness, allowing the provision even of conical three-dimensional lattice-like structures with considerable time saving. Said particular structures in fact currently require several steps and handlings on other machine tools, which usually are not in line but are located in adapted departments or sectors other than inline production and therefore require a specialized workforce and working and handling times that affect the final cost of the product.

The present invention consists of a circular deck on the inline work surface, which works in the middle of the transfer line - which generally uses rollers - for the transit of flats or already-folded nets. Said rotating deck rests on a horizontal center bearing, which is moved angularly with adapted automatic actuation means capable of preparing and positioning the products in transit so that they are rotated even by minimal angles with respect to the normal direction of work or advancement of the products. In this manner it is possible to operate on the production flow by preparing the products with a preset angle with respect to the folding machine, rapidly providing products that until now required several handlings and interruptions of the inline production flow.

Background art

In the background art, in the field of automated apparatuses for forming electrically welded metal nets and in the construction of three-dimensional lattice-like metallic structures, such as for example reinforcement frames for concrete castings, products are handled by making them glide on roller conveyors or transfer conveyors or with overhead suspended handling with the same direction as the production line flow.

These technical solutions provide lattice-like structures or products which are perfectly perpendicular. However, such structures are not always required: sometimes it is necessary to produce conical lattice-like structures, which are rather laborious on normal inline systems, and therefore it is necessary to interrupt automatic production flow in order to intervene manually on the products in transit in order to position them correctly on the folding machines so as to meet design requirements. These interventions are highly disadvantageous, since these products are not always easily obtainable, and therefore it is necessary to work with other machines which are not inline, with conveyance and associated workforce, or, if it is possible to work with inline machines, it is necessary to interrupt the continuous flow and intervene with a specialized workforce, slowing down production and affecting negatively the final cost of the product.

Moreover, another disadvantageous aspect which is well-known in the field is that on the production line of three-dimensional lattice-like metallic structures the folds occur one after the other, always in the same advancement direction of the basic net, and therefore folds of the net that are oriented for example at right angles to each other are not possible.

Therefore, in order to cope with the observed drawbacks, the present machine is provided which makes the automatic apparatus for the production and forming of structures more versatile, allowing the performing of folds with any angle on the entire perimeter of the flat net, always automatically, without any handling operations of any kind and without manual interventions, avoiding interruption of the inline production flow and avoiding interventions outside of said line by using other machines.

Summary of the invention

The aim of the present invention is therefore to provide a machine or assembly for automatic angular handling of flat net or of three-dimensional structures derived from electrically welded metal net, having the following and main characteristics:

- it is insertable in a line for the production and forming of three-dimensional structures obtained from electrically welded metal net, arranged upstream and/or downstream of the automatic folding unit;

- it is usable for the handling of products such as metal nets and/or three-dimensional structures upstream and/or downstream to serve automatic folding machines of the single type;

- it comprises a surface for resting contact or transit of products which has a flat and horizontal circular shape, and works in a production line or to serve the automatic folding machine upstream and/or downstream;

- it provides a surface which is mounted on a horizontal center bearing and can be rotated automatically in order to prepare the products with the desired angles on the subsequent folding machine;

- said circular surface is able to move angularly through 360° (multiples and submultiples) automatically in order to work in both directions of rotation to prepare the net or three-dimensional structure with the desired angle in approach to the folding machine;

- said circular surface for the movement of the flat metal net or of the three-dimensional lattice-like structures is capable of arranging them with any angle on their entire perimeter in approach to the automatic folding unit or machine;

- said rotating surface is provided with one or more movable automatic clamps, which are jointly connected to said surface and lock in position the net or the other products in transit in order to be able to ensure the programmed angle during the rotation of the surface;

- said circular surface for angular movement on the work surface has large surface dimensions in order to be able to work on metal nets that are moved by adapted systems that are suitable for the purpose, such as rollers or movement by means of overhead arms;

- the rotating handling machine allows the provision of lattice-like structural products derived from electrically welded metal net of a wedge-shaped three-dimensional type, i. e., shaped like a truncated pyramid.

Essence of the invention

The aim of the invention is achieved according to the characteristics of the main claim and/or of any other claim cited in the present patent text by providing a machine for angular movement on a surface of flat and/or three-dimensionally folded electrically welded metal nets, particularly usable in the upstream serving of units for folding in a production line or simply associated with individual folding machines.

The invention consists of a machine that makes it possible to orient correctly and with good precision the three-dimensional structure or net in approach and in service to an automatic folding assembly. In this manner it is possible to obtain folds with preset angles with any sequence in the two directions of rotation of the machine surface. In this manner, for example, it is possible to obtain folds on the entire perimeter of the flat net with any angular orientation over 360°. The angular movement machine that serves the folding assembly allows the provision of new products, new three-dimensional structures automatically in line production, which until now were obtainable only manually on single machines and not in line.

Another object of the invention is to provide a large work surface, which is preferably circular and horizontal and at the same level as the work surface of the apparatus for forming three-dimensional lattice-like structures, affecting the entire width of the transfer conveyor of the flat electrically welded metal nets or folded nets. Said work surface is supported centrally by a horizontal circular center bearing, which can be actuated automatically in order to orient said work surface, and therefore the conveyed products as well, in both directions of rotation over the entire round angle, with any angle, thus orienting the products on the transfer conveyor or in service to the inline automatic folding machine or of the individual type. Said rotating work surface is large, so as to orient rather large parts which do not interfere in their movements with other parts in transit or being worked.

The present machine makes it possible to build particular three-dimensional lattice-like structures, such as for example reinforcement cages for concrete which are wedge-shaped, i. e., shaped like a truncated pyramid or simply with perimetric folds of any angle on flat source metal nets, useful in forming more complex three-dimensional lattice-like products.

In accordance with this aim and object, the machine according to the present invention consists of a horizontal circular surface which is arranged at the same level as the transfer conveyor of the apparatus or of the work surface upstream of the folding machine, for which it performs a service function associated with a net folding machine of the automatic type both in a production line or, in some cases, serving exclusively a folding machine of the single type. Said circular surface is mounted on a suitable circular center bearing, which is arranged at the center and below said surface. The center bearing is of the automatic type and therefore can rotate angularly on the horizontal plane in both directions on command, performing even infinitesimal angular movements, orienting the net or the other lattice-like structures in approach to the subsequent machine with angles according to what is provided in the construction of particular three-dimensional structures.

Another object of the invention is to be usable as a handling unit with angular orientation upstream to serve other machines in the sector of forming three-dimensional lattice- like structures derived from electrically welded metal nets, or in other mechanical sectors, for example in the handling of metal plates or other products in other industrial sectors.

The operating method of the machine is fundamental in the construction of products that are different from the standard, particularly in the forming of lattice-like cages shaped like a frustum or otherwise wedge-shaped, indeed due to the fact that the transit surface of the products or semi-finished products can be rotated automatically with a programmed angle before presenting said products to the subsequent folding machine, and this occurs even inline in a cage forming apparatus.

Another aspect of the present invention consists in that the machine works in a continuous production line and receives the products upstream from the conveyor for transit and feeding of the apparatus or also from the downstream machine in order to be able to intervene subsequently on said product. Moreover, it can also receive parts from outside the line to then orient them correctly toward the folding machine and send them inline. It can also be used to automatically evacuate externally parts assembled by the line in an external direction that is different from the production direction (for example, the evacuation of incorrect parts or partly processed parts).

A further aspect of the invention consists in that said machine can be inserted in production apparatuses or even on single folding machines downstream of the folding unit, since it can be used to move the products in all directions and/or simply to evacuate the finished products.

Another object is to make the present machine ineffective, if necessary, for the normal transit of parts if they do not need to be oriented angularly but need to continue by following the normal advancement direction of the apparatus.

The invention fully achieves the intended aim and objects, i. e., to: provide a handling surface of the smart type, which can orient with the desired angles the flat metal nets or three- dimensional structures in approach to the folding machine (be it part of the production line or of the single type); to provide an advantage in relation to working times, with a time saving in the specific production; to use an automatic machine, avoiding the intervention of personnel within the work area of the apparatus; to provide an apparatus which is safer as a whole, since the machine orients the product automatically and is controlled from outside; to perform correctly angular orientations of the product which are constant over time, something which is not ensured by the manual and occasional interventions of operators of the apparatus or operators who serve single folding machines.

Brief description of drawings

A solution according to the present invention is illustrated by way of preferential but non-limiting example in the accompanying five drawings, wherein:

Figure 1 is a plan view of the insertion of the handling machine with a circular surface in an apparatus for the inline production of three-dimensional lattice-like structures obtained from successive folds of electrically welded metal net;

Figure 2 is a simplified side view of the preceding view, illustrating the circular center bearing on which the rotating upper surface rests, said surface supporting the metal net formed by electrically welded steel rods;

Figure 3 is a perspective view of an electrically welded metal net with steel rods crossed at right angles;

Figure 4 is a perspective view of the net according to the preceding figure, showing that indeed by means of the rotation of the net on the surface of the handling machine it is possible to perform perimetric folds of the net which are perpendicular to each other and were hitherto impossible in a production line. This example of three-dimensional product highlights the usefulness of the handling machine upstream of a folding machine; Figure 5 is a plan view of an electrically welded metal net, with mutually perpendicular steel rods, illustrating the possible folding lines, of the mixed type, i. e., parallel and inclined with preset angles;

Figure 6 is a plan view of a frustum-shaped lattice-like cage obtained according to the folding lines shown in the preceding figure as a second example of product obtainable with the handling machine.

As can be seen from the various figures, the machine 3 for angular movement on a surface of flat electrically welded metal nets 4 or other semi-finished products is inserted inline in an apparatus for the continuous production of three-dimensional lattice-like cages 1, upstream of an automatic folding assembly 2, but can also be used to serve, and be associated with, a folding machine of the single type.

The machine consists of a flat horizontal surface for the transit of the material, which is circular and is mounted on an adapted horizontal circular center bearing 6 with a vertical rotation axis 5. It is capable of performing, automatically or with manual commands, angular rotations in both directions through the entire round angle. In this manner it can orient the net 4 or the intermediate product with any angle of approach to the subsequent machine, such as for example the folding unit 2. Therefore, it allows to perform folds with any perimetric orientation of the net 4: it can perform, as in the illustrated example, identical or different folds of the peripheral rods 4.1 and 4.2, bending them respectively 8, 8.1 and in the shape of a beam 8.2, with perpendicular or other angles for each net shaping sequence, thus forming a semi-finished product 7 that can constitute a base for a new, more complex lattice-like structure that can be used in the building sector.

Furthermore, the rotating work surface 3 is provided with automatic clamps 11 - for example, five have been drawn - which are meant to grip and keep in position the electrically welded net 4 or the other three-dimensional products during the rotation of said surface; this is done to ensure that the correct programmed angle of said products is reached and maintained. Said automatic clamps are retractable with respect to the work surface in order to facilitate the movement of the products and are activated on command before and after the movement of the upper circular table.

Furthermore, the automatic machine for angular orientation of semi-finished products allows execution in automatic sequences of various angles, having identical or different values, in order to perform, for example on a flat metal net 4, different folding lines having the same orientation as the preceding one 9 or having a different angle α, in order to obtain wedge-shaped three-dimensional lattice-like products 10 and/or products shaped like a truncated pyramid and/or a truncated cone. The machine is extremely advantageous, since it is provided with a horizontal circular center bearing 6 which has remote automatic control, is extremely precise and reliable, and performs sequences of rotations of the circular work surface 3 that ensure absolute repeatability over time by means of the storage and management systems of the computerized type.

Of course, the invention is not limited to the embodiment of the machine described above, starting from which it is possible to provide other embodiments and ways of carrying it out, and the details of execution may in any case vary without thereby abandoning the essence of the invention as stated and claimed hereafter.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.