DE102005031579A1 - Fasteners for transponders for the identification of metallic or metal-containing objects via radio-based transponder technology (RFID) - Google Patents

Abstract

The invention relates to a fastening means for transponders for the identification of metallic or metal-containing objects via radio-based transponder technology (RF-ID), the distance between the transponder and the container being ensured by a dielectric spacer or spacer feet, characterized in that the spacer or feet are attached to the container by means of magnetic force.

Description

The The invention relates to a fastening means for transponders for identification of metallic or metal-containing objects via radio-based transponder technology (RFID), whereby the transponder at the metallic objects means Magnetic force temporary is attached.

In automated logistic environments, e.g. Production, warehouse, Shipping, transportation, are for material tracking or control Products, containers, packaging, packages, etc. i. d. R. by barcode etiquette identified. In many cases, these objects are transported together or repackaged, so that all barcodes are not always directly from the outside are readable, and the objects must be separated to make the necessary visual contact to produce the barcodes. These expenses for separating or breaking up of packaging / transport safeguards due to identification or inspection could be avoided if the objects transported together too could be identified without visual contact. The usable for this Technology is under the keyword RFID (Radio Frequency Identification) known, i. Transponder (electronic chip with antenna) and readers based electromagnetic waves. The RFID technology is already at non-metallic or non-metal objects used, but is for the identification of metallic or metal-containing objects (e.g., containers, barrels, Container) problematic, since this is an inhibitory to insulating Effect for possess electromagnetic fields.

JP 2004-217221 A describes a method for attaching a transponder to a metal container, wherein an installation gap for the transponder is provided in the container. The transponder is inserted in this gap. Transponders and containers require a special production. Only a low to medium range of a few centimeters is achieved. EP 1 447 769 A1 relates to the arrangement of an active transponder on metallically conductive containers, wherein the transponder must be placed as close as possible to the surface or even integrated in the surface at a certain point of the container, so that the transponder is energized by induction of the conductive surface. This increases the range of the signal. However, the phenomenon described requires accurate placement of the transponder on the container. The marking method is correspondingly difficult in practice and, because of the use of active transponders, considerably more expensive in comparison to passive transponders.

EP 1 083 519 A2 also describes a Befestigungsytem for an active transponder - consisting of a flow element, a chip and an antenna - on a metal bottle or a metal container. The transponder is attached, for example, on a collar on the bottleneck, so that the flow element is removed from the bottle a distance d filled with air. Alternatively, the transponder is mounted on a dielectric spacer, which in turn is attached to the metal container. The attachment method to the container is not specified. Active transponders have the advantage that they have a higher transmission range than passive transponders, but have the disadvantage that they show a shorter life and are significantly more expensive. The applicability of the fastening system for passive transponders was in EP 1 083 519 A2 not tested.

In order to the technical and economic benefits of RFID technology in the identification of metallic or metal-containing objects from several meters reading distance for material tracking / control be used in a logistical environment, it requires a fastening method as possible for passive Transponders that have a greater range of the signal despite the inhibiting to insulating effect of metallic or metal-containing objects.

• – dass sie umknicken/an den metallischen Container gepresst werden können und dadurch nicht mehr lesbar werden
• – dass sie bei Transport des Containers beschädigt bzw. zerstört werden können
• – dass sie bei Entfernung vom Container unweigerlich zerstört werden und nicht wieder verwendbar sind
• – dass die automatische Etikettierung einen speziellen Falt- und Spendestempel erfordert.

The Finnish company Fa. UPM-Rafsec markets the so-called FlagTag transponder labels for the marking of metal containers. In these, the transponder is embedded like a flag in a label that is glued to a container / container. The transponders are more or less perpendicular to the metallic object surface. The transmission of the signal is carried out with suitable reading antennas (circulating antenna field) without interference, as long as the transponder antenna does not fold over and thus does not get too close to the metallic object surface. Disadvantage of Flag Tag Transponder Labels is

• - That they can be bent / pressed against the metallic container and thus become illegible
• - that they can be damaged or destroyed during transport of the container
• - That they are inevitably destroyed when removed from the container and are not reusable
• - that automatic labeling requires a special folding and dispensing stamp.

It is an object of the invention to provide a mounting method for active or passive transponders on metallic or metal-containing objects which are resistant to the stress of transport is resistant, in which the insertion of the transponder is practical and fast, the transponder used is reusable, and a greater range of the signal (a few inches to several meters) despite inhibitory to insulating effect of the container is possible.

These is achieved by the fastening means according to the invention for transponders for the identification of metallic or metal-containing objects via radio-based Transponder technology (RF-ID) solved, whereby the distance between the transponder and the container by a dielectric spacer or spacer feet guaranteed is, characterized in that the spacer or feet by means of Magnetic force are attached to the container.

The The invention relates to the attachment of transponders to metallic or metal-containing objects by means of magnets, in particular magnetic foil or vapor-deposited magnetic layers or incorporated in labels Magnetic foil.

Surprisingly In this case, the magnet does not influence the reading properties of the transponder negative; the transfer the signal is over greater range trouble-free. Other advantages of the magnet are that the transponder is light and non-destructive insert or remove and thus reusable. In addition, the transponder parallel to the surface attached and is therefore less against the stress of transport susceptible.

The invention Mounting system is suitable for level as well as for uneven, round or wavy surfaces of metallic or metal-containing Objects. Consists of uneven, wavy or round surfaces the spacer and / or the filling material and / or the magnetic film or the magnetic layer of a flexible, flexible, non-rigid material.

The Transponder technology for metallic or metal-containing objects at reading distances of several Meters can be made by using transponders with magnetically adhesive Coatings used in the UHF frequency range between 300 to 3 GHz become. The UHF transponders - typical from 700 Mhz - be in the market as adhesive labels or as cardboard or plastic cards offered.

The invention Mounting system is suitable for all types of transponders.

The Transponders have to at a distance to the metallic / metal-containing surface of the be attached to identifying objects. This distance is dependent from the object to be identified, sometimes a distance is sufficient of 1 mm, in other cases can 20 to 30 mm may be required. The necessary distance also depends of the readers used, their antenna performance and from the reading distance and must be in Be determined on an individual basis. The size of the transponder is included not essential.

Of the Transponder can by means of spacers (air bridge) or by means of spacer of dielectric Material such as foamed Material, cardboard, plastic, paper or even air from that to be identified be kept away metallic or metal-containing object. As a spacer can also resilient spirals are used. When used on circular surfaces offer flexible or slightly flexible spacers / filling materials / magnetic foil. At the spacer or the spacer can magnets, magnetic feet, magnetic films or vapor-deposited magnetic layers for easy adhesion be attached to metallic objects.

This Construction could as an integrated transponder, e.g. Paper or PVC labels, plastic card or cardboard transponders, being thin Magnetic foil or a magnetic layer in bendable ends embedded / evaporated on the transponder. By bending the Ends of the transponder becomes an air gap between transponders and metallic surface, Spacers / filler is not needed in this case.

The shape of the spacer, the feet of dielectric material, the transponder, the magnetic base, the strip, the foil or the deposited magnetic layer is arbitrary. The tree shape is usually based on the material used, the usage requirements and the economy. As economic and easy to use variant, the design loud 5 (Spacer material air, label design with foldable ends and integrated magnetic strip) are exposed.

Magnetic feet, magnetic foil or magnetically deposited layers are 0.01 to 3 mm, preferably from 0.1 to 1mm thick from the necessary magnetic attraction on the to be identified Objects and the unevenness of the object surface.

The reader is understood not only to read but also to write transponder data. 1-n antennas are connected to the readers themselves to enable the reading and writing of transponders. The antennas of the transponders must normally be aligned with the antenna field of the reader in order to achieve good readability. There is Antennas for the RF-ID readers, which can generate a circularly polarized antenna field by electronic control. By using such antennas, the position of the transponder to the antenna field no longer plays a major role, ie the orientation of the transponder when attaching to the objects need not be carefully considered.

The invention Attachment of the transponder is suitable for normal as well as for circular polarized antenna fields of the readers.

The Antennas of a reader, i.e. the so-called "club shape of the RF field ", should preferably be aligned from above on the objects to be identified be. Side-facing antenna panels would because of which increased at UHF Reading range of several meters may also identify objects, that are not in the "identification area" (e.g., side by side lying loading gates). On a pallet can stand several steel barrels, and the inside barrels can only be read by attaching the transponder on the drum lid. The lateral attachment of the transponder to the inner barrels and close the lateral reading Out here, because the neighboring barrels the transfer of the signal.

The transfer the signal occurs between the magnetically attached transponder and the reader in a range of typically 0.1 to 10 m, preferably 0.1 to 4 m, more preferably 0.1 to 2 m. A typical application distance is 0.1 to 4 m. The bigger the Distance of the transponder from the metallic surface is the bigger the reading range of the transponder. Distances of more than 5 cm act no longer have a positive impact on reading distance.

One embodiment The invention will be explained below with reference to accompanying figures without limited to this to be.

view of the page:

1 : Transponder 1 with spacer example 3 and evaporated magnetic layer 4

2 : Transponder 1 with spacer example 2 and magnetic feet 4

3 : Transponder 1 with slightly flexible spacer / filler 3 and magnetic feet 4 for wavy surfaces

4 : Transponder 1 with spacers 2 and flexible magnetic foil 4 for round surfaces and soft filling material 5

4a : Transponder 1 with spacers 2 , flexible magnetic foil 4 for round surfaces without filling material

5 : Transponder with optional bendable ends 1 + 3 and integrated magnetic layer 4

View from above:

6 : Transponder 1 with angled ends and magnetic foil / magnetic layer 2 + 3

7 : Transponder 1 with surface-filling spacer 2 and magnetic foil 3

8th : Transponder 1 with non-surface-filling spacer 2 and magnetic layer 3

Production of exemplary embodiments:

In a first embodiment ( 1 ) was on one side of a cut spacer 3 made of cardboard, foam, Styrofoam, etc. a transponder 1 glued on the other side, a magnetic film or a magnet was glued or a magnetic layer 4 evaporated. Similarly, one can imagine paper or PVC labels being incorporated into the magnetic film.

In another embodiment, 2 pieces of magnetic tape were used 4 with a distance next to a transponder 1 placed on the adhesive side of a label. The distance between the transponder and the two magnetic film pieces was chosen so that when kinking the resulting label ends a distance foot and thus an air bridge between transponder 1 and magnetic foil pieces 4 corresponding 5 arises. The label was folded down to the transponder 1 and the magnetic film pieces 4 to enclose.

Transmission tests:

6 transponders UHF 868 MHz, commercially available manufacturer UPM-Rafsec, were using 15 mm spacer made of cardboard and a 0.3 mm thick magnetic film ( 1 ) each placed on the lid of 6 steel barrels volume 60 liters. One of the steel barrels was filled with water. All 6 barrels were driven on a pallet with rollers several times under reading antennas. The reading antennas were mounted in a range of 1 to 2 m from the upper edge of the barrels, the antenna field was thus directed from the top of the transponder in the drum lids, power 2W, manufacturer of the UHF reader Fa. Samsys. All transponders could be identified that filled with water Barrel and a barrel of 200 liters volume produced no difference in the identification attempts. The smaller the distance of the transponder to the metallic surface, the more read errors were detected. Adding or removing the magnetic sheet did not affect the result.

in the In comparison, transponders were incorporated into adhesive labels and glued in quasi-direct contact with the metallic surface, the transmission of the identification data of transponders was from the steel barrels used completely prevented at a reading distance of 0.1 m and more.

Same Tests with UPM-Rafsec's flag tag labels, in which the transponder folded away from the label positioned perpendicular to the metallic surface were, only gave good identification results, as long as the folded transponder at an angle of close to 90 degrees to metallic surface were positioned. Because the flag tag labels are made from plain label stock (e.g., paper or PVC film), the transponder may pass through its own weight or due to external influences (e.g. Humidity, temperature, mechanical forces) fall back onto the adhesive label surface. Our experiments showed that the farther the unfolded transponder the 90 degree position left to so more read errors occurred. The glued flag tag labels were Destroyed in any case during removal attempts.

at all experiments clearly stated that the reading distance between antennas and transponders considerable influence on the minimum necessary distance of the transponder to the metallic one surface Has.

The Thickness of the magnetic foil is for the identification of the transponder is not decisive. In a similar Trial with steel barrels A magnetic strip with a thickness of 8 mm was used, the insulating ones spacers were correspondingly thinner held. Thereafter, it was found that the thickness of the magnetic film no Influence on the identification quality of Transponder owns. Therefore, the magnetic force needs only so To be strong, that ensures a secure attachment of the transponder is. Naturally can additional requirements for a stronger one Speak magnetic force, e.g. Impact resistance or manual removability, be considered in individual cases.

In in another attempt, the transponders became magnetically adhesive on the side of the barrels attached. The reading antennas were also aligned laterally. The test result was the same as with the reading from above the transponders in the drum lids. Here, however, had to pay attention be sure that every barrel with the transponder side towards the Antenna field was rotated. That the transponders could not get through the barrels through when the transponders are facing away from the reader were. The use of multiple antennas from different sides could improve the result though. But with identification of several objects simultaneously (e.g., several barrels on a pallet) some barrels not because of metallic shielding by the other barrels more reliable recognized.

So long no metallic objects on top of each other The identification from above is the more advantageous one stacked up Variant.

Claims (7)

Fastening means for transponders for the identification of metallic or metal-containing objects via radio-based transponder technology (RF-ID), wherein the distance between the transponder and the container is ensured by a dielectric spacer or spacer feet, characterized in that the spacer or feet by means of magnetic force on Containers are attached. Fastening means according to claim 1, characterized in that that the magnetic force through Magnetfuss, magnetic strip, magnetic foil or vapor-deposited magnetic layer is applied. Fastening means according to claims 1 or 2, characterized that the dielectric spacer or the feet and / or the magnetic layer and / or the transponder integrated are. Fastening means according to claims 1 to 3, characterized that the spacer and / or the filling material and / or the magnetic film or the magnetic layer of a flexible, flexible, non-rigid material when a Magnetic transponder attached to uneven, wavy or round surfaces shall be. Fastening means according to claims 1 to 4, characterized that the spacer or the feet of dielectric material and / or the transponder and / or the Magnetic foot, the magnetic strip, the magnetic sheet or the deposited magnetic layer consists of any type. Fastening means according to claims 1 to 5, characterized that the magnetic base, the magnetic strip, the magnetic foil or the magnetic layer is 0.01 to 20 mm thick. Fastener according to claims 1 to 6 da characterized in that the transponder with the UHF frequency range between 300 to 3 GHz ensures interference-free transmission of the signal from 0.1 m to 10 m.