The present invention relates to a method and an apparatus for making a radio-frequency identifying device, commonly known as RFID transponders, provided with antennas made of electrically conductive wire, for example copper wire.

RFID transponders consist of two essential parts, the so- called antenna, made of electrically conductive material and an integrated circuit, or microchip, connected to the two ends of the antenna.

Making the antenna with a thin wire made of electrically conductive material is known, for example of a copper wire with a diameter of no more than by connecting the ends to a module, also known as a strap or interposer, which comprises the integrated circuit or microchip.

In the prior art methods and apparatuses are known for making antennas of copper wire which form the antenna of the RFID transponder on a substrate by depositing and fixing the wire on the substrate that is then used in subsequent processing. Nevertheless, these methods and apparatuses require a long time for each production cycle inasmuch as it is necessary to "drawing" the antenna.

In fact, in order to deposit the wire, a certain number of heads are arranged, for example six, each of which, supplied by a spool of copper wire, deposits the wire on a substrate, normally of PVC. These heads move, tracing with the wire the draw of the antenna and attaching the wire to the substrate by a small hammer vibrating at an ultrasonic frequency that follows the movement of the head. The substrate either has to be of a material that softens with the heat generated by the vibrating hammer, retaining the wire, like PVC, or has to be coated beforehand with a product that performs the same function .

The heads for depositing the wire have to be able to rotate 360° because as the course of the antenna develops the small hammer always has to follow the deposition of the wire.

The heads that are thus constructed have relatively complex and heavy mechanisms, which means that both for economic reasons and for reasons of motion inertia, the number of heads that can be applied to an apparatus is relatively small. This causes a very high cost/productivity ratio.

An apparatus of the type mentioned above is disclosed in international patent application WO2011/098892.

Using a coil winder to form a High Frequency band antenna (HF or High Frequency 13.56MHz) is also known, the shape of which consists always of a spiral, see for example WO 91/16718, nevertheless, with this method, the coils are adjacent and superimposed.

In RFID transponders operating in the UHF (Ultra High Frequency) , at a frequency varying from 860 to 960MHz, depending on the regulations of the various countries, the antenna is never spiral-shaped but consists of a monopole, a dipole, of a circle formed by a single coil or of a combination of the aforesaid shapes.

For reasons of space or of efficiency, the normally rectilinear portions of the monopoles or dipoles can be curved to form loops or meanders.

In all cases, an UFH band antenna can never be manufactured using a coil winder.

The present invention proposes providing a method and an apparatus for making UHF band RFID transponders provided with an electrically conductive wire antenna, for example a copper wire, which enable productivity to be increased and costs to be reduced with respect to the methods and apparatuses known from the prior art.

In particular, the present invention proposes supplying a method and an apparatus that enable an electrically conductive wire antenna to be made completely before depositing the antenna on a substrate on which an RFID device is completed. The object of the invention is achieved with a method according to claim 1 and with an apparatus according to claim 5.

Owing to the invention, it is possible to make an electrically conductive wire antenna completely, that is, for example, made of copper wire, without it being necessary to deposit the wire on a substrate whilst the antenna is being made, it being possible to fix the antenna to a substrate at the end of the making thereof.

The apparatus according to the invention comprises antenna forming means that is simple to make and of reduced mass. This enables very high productivity to be obtained, which is significantly above the productivity of apparatuses known from the prior art owing to the extremely reduced cycle time for forming the antenna.

A non-limiting embodiment of the invention is disclosed below, with reference to the attached drawings, in which: Figure 1 is a perspective view of an apparatus according to the invention in a first step of making an electrically conductive wire antenna;

Figure 2 is a top view of a detail of Figure 1;

Figure 3 is a perspective view like the one in Figure 1, relating to a second step of making the antenna;

Figure 4 is a further perspective view of the apparatus according to the invention in a third step of making the antenna;

Figure 5 is a still further perspective view of the apparatus according to the invention in a fourth step of making the antenna;

Figure 6 illustrates an antenna made with an apparatus according to the invention, fixed to a substrate and connected to a microchip to obtain an RFID device ;

Figures 7, 8, 9 illustrate a version of the apparatus according to the invention;

Figure 10 illustrates an antenna configuration that is makable with the version of the apparatus according to the invention illustrated in Figures 7, 8 and 9;

Figures 11 and 12 illustrate a detail of the operation of the apparatus illustrated in Figures 1 to 6;

Figure 13 illustrates a modification to the apparatus according to the invention;

Figures 14 to 18 illustrate a further version of an apparatus according to the invention;

Figure 19 illustrates a still further version of an apparatus according to the invention.

With reference to Figure 1, an apparatus 1 according to the invention comprises a supporting and locking element 2 shaped as a portal fixed to a respective supporting element (not shown) . The portal element 2 can rotate around a substantially vertical axis 3 and can move in a direction parallel to said axis 3. The portal element is provided, at the lower ends 4a and 4b with a first gripping element 5a and with a second gripping element 5b that are suitable for grasping a wire 6 made of electrically conductive metallic material, for example a copper wire, which is unwound from a coil (not shown) and is intended to constitute an antenna for an RFID device.

The apparatus 1 further comprises a first forming element 7a and a second forming element 7b, facing one another, intended for giving an antenna 8 (Figure 7) a desired shape, for example a loop shape. The first forming element 7a and the second forming element 7b are both movable in a direction that is perpendicular to said axis 3.

The first forming element 7a, comprises a first crosspiece 9a to which a plurality of first rods 10a is fixed that are parallel to one another each of which terminates with an end 11a that comprises a shaping element 12a, for example cylindrical, that is slidable inside said end 11a. The rods 10a, in the embodiment shown, are three, but can also be more or less than three.

The second forming element 7b comprises a second crosspiece 9b to which a plurality of second rods 10b is fixed that are parallel to one another and a pair of third rods 10c placed on opposite sides with respect to the second rods 10b and parallel to the second rods 10b. Each second rod 10b and each third rod 10c ends with a respective end lib, 11c, which comprises a respective shaping element 12b, 12c, for example cylindrical, that is slidable inside the respective end lib, 11c.

The distance between the first rods 10a, between the second rods 10b and between the third rods 10c is chosen in such a manner that the first rods 10a can be inserted into the gaps between the second and third rods 10b, 10c, and the second rods 10b can be inserted into the gaps between the first rods 10a.

Each third rod 10c is provided, on a face located opposite the second adjacent rod 10b, with a cutting element 13 intended for cutting the wire 6.

The number of second rods 10b is equal to the number of the first rods 11a less one unit. In the embodiment illustrated, the second rods lib are two in number.

Below, the operation of the apparatus 1 according to the invention is disclosed.

In a first step, shown in figure 1, the first gripping element 5a grasps the free end of the wire 6. Subsequently, in a second step, the portal element 2 rotates by 180° around the rotation axis whilst the wire 6 is maintained tensioned by a tensioning device that is not shown.

In a third step, shown in Figure 3, after the portion A of wire 6 has been grasped by the first gripping element 5a, the portal 2 lowers, until said portion of wire A is at the level of the shaping elements 12a, 12b and 12c that protrude below from the ends 11a, lib and 11c of the first rods 10a ₇ of the second rods 10b and of the third rods 10c, respectively.

Subsequently, the first forming element 7a and the second forming element 7b are moved towards one another, in a direction that is perpendicular to the rotation axis 3 of the portal 2. During this movement, the first rods 10a are inserted into the gaps between the second rods 10b and between the latter and the third rods 10c and the shaping elements 12a, 12b and 12c interact with the portion A of wire 6 in such a manner that it assumes a loop configuration, like the one shown in Figure 6, which constitutes the profile of the antenna 8.

During this movement the tensioning device releases the necessary quantity of wire and at the end of the movement the gripper 5b closes.

Figure 11 shows the position of the wire 6 with respect to the forming elements 7a, 7b during forming of the antenna, showing how the wire 6 is at the level of the shaping element 12a, b, c that protrudes with respect to the respective rod 10a, b, c of the respective forming element 7a, 7b, and how the wire 6 and the forming elements 7a, 7b are spaced away from the substrate 14.

Subsequently, the forming elements 7a and 7b are lowered until the antenna 8, consisting of the portion of shaped wire A, is pressed on a substrate 14 intended to act as a support for the RFID device. During movement to the bottom of the portal 2, the shaping elements 12a, 12b and 12c, coming into contact with the substrate 14, retract, sliding upwards, but remaining protruding below the respective forming element 7a, 7b by a quantity corresponding to the diameter of the wire 6, in such a manner as to maintain the latter in the desired shape for the antenna 8, as illustrated schematically in Figure 12. Alternatively, instead of lowering the forming elements 7a and 7b, it is possible to raise the substrate 14 until the substrate 14 is brought into contact with the antenna 38 and press the substrate 14 against the antenna 38. The surface of the substrate 14 on which the antenna 8 is pressed can be advantageously covered with a layer of adhesive substance, in such a manner as to ensure that the antenna 8 adheres to the substrate 14. Alternatively, the substrate can be covered with a pasty substance in which the wire can penetrate and remain retained, such as, for example, rubber or silicone that have not yet been vulcanised. A further alternative provides that the forming elements 7a and 7b and, consequently, the wire 6 are heated, permitting the latter to penetrate any thermoplastic material by heat and pressure, or provides that the wire itself is covered with hot-melt adhesive. Whilst the antenna 8 is pressed on the substrate 14 the cutting elements 13 separate the antenna 8 from the rest of the wire 6 and, lastly, the gripper element 5a is opened by eliminating the cut wire remaining in the gripper 5a and enabling the apparatus 1 to return to the initial position illustrated in Figure 1, to restart the forming cycle of an antenna 8.

Other configurations are possible using forming elements of different shape or moving the elements by motors, cams or other means.

The cycle restarts with the gripper 5b closed and the gripper 5a open.

During rotation, the length of wire that remains outside the cutting element is recovered.

Lastly, a microchip module 15, previously applied to the substrate 14, is welded onto the antenna 8 to complete the RFID device, as shown in Figure 6.

The welding step can be performed at the same time as the deposition step by means of welding devices that are not shown that are positioned in a suitable position directly in the forming elements.

In Figures 7, 8 and 9 a version la of an apparatus according to the invention is illustrated that is suitable for making a loop-shaped antenna 16, i.e. an antenna 16 having the shape of a half-ring 17 with ends 18 and 19 that converge on one another. In Figures 7, 8 and 9 only the forming elements 20a and 20b are shown, in a plan view, in three different operating positions, whereas the portal element 2 has been omitted, inasmuch as it is identical to the portal element of the embodiment of the apparatus 1 illustrated in Figures 1 to 5. The first forming element 20a comprises a first crosspiece 21a to which a first rod 22a is fixed stiffly that terminates with an end 23a in which a shaping element 24a is slidable. The second forming element 20b comprises a second crosspiece 21b to which a pair of second rods 22b is connected, each terminating with a respective end 23b in which a respective shaping element 24b is slidable. The second rods 22b are connected to the second crosspiece 21b in such a manner as to be able to rotate on a plane that is perpendicular to the rotation axis B of the portal 2.

In Figure 7 a first operating position of the forming elements 20a and 20b is illustrated in which there is a certain space between the end 23a of the rod 22a and the ends 23b of the rods 22a and 22b are parallel to one another. The portion of wire A locked between the gripper element 5a of the portal 2 and a tensioning device, which is not shown, is located in said space.

In Figure 8 a second operating position of the forming elements 20a and 20b is illustrated that are moved towards one another until the end 23a of the first rod 22a is inserted between the ends 23b of the second rods 22b, so as to cause a divarication of said second rods 22b. In this second operating position, an intermediate portion Al of the portion A of wire is bent into an arc around the shaping element 24a of the first rod 22a until the end portions A2 and A3 of the portion A of wire are arranged parallel to one another .

In Figure 9 there is illustrated a third operating position of the forming elements 20a and 20b, in which the latter have been moved closer together until the end 23a of the first rod 22a exceeds the ends 23b of the second rods 22b, in such a manner that said second rods 23b return, for example through the effect of elastic returning means that is not shown, to mutually parallel positions. In this manner, the ends A2 and A3 are bent in such a manner as to converge on one another until an antenna 16 in a loop configuration (Figure 10) is obtained that consists of a half-ring 17 with ends 18 and 19 that converge on one another.

The antenna 16 that is thus formed is lastly pressed on the substrate 14 to adhere thereto and a microchip is welded on the ends 18 and 19 of the antenna 16.

In Figure 13 a modification to the apparatus according to the invention is illustrated in which the portal-shaped supporting and locking element 2, with which the first gripping element 5a and the second gripping element 5b are associated, is replaced by a supporting and locking element 45 that comprises a first gripping element 25 that is fixed and a second gripping element 26 that is slidable along a guide 27 that extends in a direction that is perpendicular to the rods 10a, 10b, 10c, or to the rods 22a, 22b. The first gripping element 25, which is fixed, is arranged on a side that is opposite the coil that supplies the wire 6 that is intended to constitute the antenna.

At the start of the antenna forming cycle, when the first forming element 7a, 20a and the second forming element 7b, 20b are in an open position, i.e. in the illustrated position, for example, in Figures 2 and 7, the second gripping element 26, which is movable, grasps an end of the wire 6 from the coil that supplies the wire 6 and moves along the guide 27 until the end of the wire 6 is taken at the fixed gripper 25, which closes, whilst the second gripping element 26 opens and returns to the initial position.

After the antenna 8, 16 has been formed, the second gripping element 26 closes and the forming elements 7a, 7b; 20a, 20b lower until the antenna 8, 16 is brought into contact with the substrate 14 and, simultaneously, the wire 6 is cut and the first gripping element 25 opens. Lastly, after the first forming element 7a, 20a and the second forming element 7b, 20b have returned to their initial positions the cycle restarts .

In Figure 13 the first gripping element 25 and the second gripping element 26 are shown in association with the embodiment of the apparatus according to the invention illustrated in Figures 1 to 6, but can be equally used in the embodiment of the apparatus according to the invention illustrated in Figures 7 to 10.

In Figures 13 to 18 a further embodiment is shown with an apparatus according to the invention that is suitable for forming a spiral-shaped HF band antenna 38 (13.56 MHz) that has the coils spaced apart from one another, as occurs in the methods that arrange the wire by movement on the Cartesian axes .

This embodiment of the apparatus according to the invention comprises a plate 28, for example of quadrangular shape, connected to a shaft 29 that is rotated by a motor (not shown) .

At each corner of the plate 28 at least one group of shaping elements 30a, 30b, 30c, preferably two groups of shaping elements is arranged. Each group of shaping elements comprises a plurality of shaping elements aligned along a direction that is tilted with respect to the sides of the plate 28.

The shaping elements 30a, 30b, 30c of each group of shaping elements have a length that increases progressively towards the inside of the plate 28. This means that the first shaping element 30a, that is nearer the edge of the plate 28, has a length that is less than that of the shaping elements 30b and 30c and that the last shaping element 30c, which is further from the edge of the plate 28, has a greater length than that of the other shaping elements 30a and 30b.

A first further shaping element 31 and a second further shaping element 32, which are also slidable in a direction that is perpendicular to the plate 28, are arranged near a side of the plate 28, the first further shaping element 31 being nearer the side of the plate 28 than the second further shaping element 32.

The shaping elements 30a, 30b, 30c, 31, 32, can be pin shaped, as illustrated in Figures 14 to 18, or shaped as arched blades to make an antenna in which the corners of the spiral are rounded.

Lastly, the plate 28 is provided with a first gripping element 33 and with a second gripping element 34, arranged in an intermediate position between a side of the plate 28 and the rotation shaft 29. Each gripper element comprises a movable jaw 36, fixed to a rod 35 that can be made to slide, by an actuating device that is not shown, in a direction that is perpendicular to the plate 28.

Also the shaping elements 30a, 30b, 30c, 31 and 32 are slidable in respective through holes made in the plate 28. The rods 35 can also slide in respective holes made in the plate 28. Alternatively, the plate 28 can be provided with a central opening and the rods 35 can be made slidable in supporting elements fixed to the internal edge of said opening .

The plate 28 is further provided below with seats 44, in which the movable jaws 36 of the first gripping element 33 and of the second gripping element 34 can be inserted.

Below, making an HF band antenna 38 in the form of a spiral is disclosed.

At the start of forming cycle of the antenna 38 a free end of the wire 6 intended for forming the antenna is retained by the first gripping element 33 and the wire 6 is guided by a wire-guiding element 37 that is aligned, in a direction that is perpendicular to the plate 28, with the first shaping element 30a of each group of shaping elements 30a, 30b, 30c. All the shaping elements 30a, 30b, 30c, 31, 32 protrude from the lower face of the plate 28.

By rotating the plate 28 by the rotation shaft 29, the wire 6 is shaped and guided by the first further shaping element 31 and by the first shaping elements 30a, thus forming the first coil of the antenna 38. When the plate 28 has performed a complete revolution, the wire-guiding element 37 lowers until it is lower than the lower end of the shaping elements 30a, in such a manner that, whilst the plate 28 continues to rotate, the wire 6 is shaped and guided by second shaping elements 30b, thus forming a second coil of the antenna 38 (Figure 16) . At each revolution of the plate 28 the wire- guiding element 37 lowers in such a manner that the wire 6, at each revolution of the plate 28, is shaped and guided by successive shaping elements that are increasingly distant from the edge of the plate 28 until the last coil of the antenna 38 is made, after the wire 6 has been shaped and guided by the last shaping elements 30c. At this point, the wire 6 is passed around the second further shaping element 32 and locked by the second gripper 34, the movable jaw 36 of which moves to the closed position.

Alternatively, the wire-guiding element can move downwards progressively and not at each revolution.

Lastly, the plate 28 is lowered until it brings the antenna 38 into contact with a substrate 14 to which the antenna has to be fixed and presses the antenna 38 against the substrate 14. Alternatively, instead of lowering the plate 28, it is possible to raise the substrate 14 until the substrate 14 is brought into contact with the antenna 38 and the substrate 14 is pressed against the antenna 38.

When the plate 28 and the substrate 14 are pressed against one another, the shaping elements 30a, 30b, 30c, 31 and 32 move upwards, sliding in the respective holes in such a manner that the antenna 38 is pressed against the substrate 14 (Figure 17), thus enabling the antenna to be fixed to the substrate 14.

The surface of the substrate 14 on which the antenna 38 is pressed can be advantageously covered with a layer of an adhesive substance, in such a manner as to ensure that the antenna 38 adheres to the substrate 14. Alternatively the substrate can be covered with a pasty substance in which the wire 6 can penetrate and remain retained, like for example, rubber or silicone that have not yet been vulcanised. A further alternative provides for the wire 6 being heated in such a manner that it can penetrate any thermoplastic material through heat and pressure, or that the wire is covered with hot-melt adhesive.

Whilst the antenna 38 is fixed to the substrate 14, the wire 6 is cut immediately before the second gripper 34 and, whilst the plate 28 is lifted again, or the substrate 14 is lowered, the gripper 33 is opened, then, by a rotation of the plate 28 the wire is moved to the gripper 33, which closes, and the gripper 34 is opened and the ends 39, 40 of the antenna 38 are connected by welding 42, 43 to a microchip module 41, previously fixed to the substrate 14.

In Figure 19 a still further version of the apparatus according to the invention is shown that differs from the version illustrated in Figures 13 to 18 through the fact that instead of the quadrangular plate 28 a plate 46 of circular shape is provided. The shaping elements 30a, 30b, 30c of each group of shaping elements are aligned along substantially radial directions. The groups of shaping elements 30a, 30b, 30c can be spaced apart from one another by a substantially constant angular pitch if it is desired to make an antenna having the shape of a regular polygon or with a variable angular pitch if it is desired to make an antenna that has the shape of a non-regular polygon, for example with a rectangular shape.

The plate with which the shaping elements 30a, 30b, 30c are associated can have, in addition to the quadrangular shape illustrated in Figure 13, or to the circular shape illustrated in Figure 19, also the shape of a regular or irregular polygon.

It should be further noted that the substrate 14, in all the disclosed versions of the apparatus according to the invention, can be arranged above the forming elements rather than below them. In this case, the shaping elements are associated with elastic elements, for example springs, that maintain the shaping elements pushing upwards until they come into contact with the substrate 14, which pushes the shaping elements downwards in such a manner as to enable the antenna to be deposited on the substrate 14. After the antenna has been fixed to the substrate 14, when the latter is moved away from the forming elements, the shaping elements are again pushed upwards by the respective springs. By associating the shaping elements with springs that push the shaping elements in a preset direction, it is possible to position the forming elements and the substrate in any manner, for example both vertical or tilted with respect to the vertical at any angle. In the practical embodiment, the materials, the dimensions and the constructional details can be different from those indicated but be technically equivalent thereto without thereby falling outside the scope of the present invention.