Method to produce a rod tag and tag produced by the method

Abstract

A method to produce a rod tag and tag produced according to the method, wherein the method comprises at least the steps of: providing a magnetic core having a cylindrical shape and two end, winding a wire around said core to form an antenna, positioning in longitudinal extension a chip at one of the ends of said rod where the wound wire ends terminates, bonding said wire ends to contacts of said chip, displacing said bonded chip at least partially on said end of said rod, and introducing said core with said wire and said chip in an encapsulating means containing a stabilizing material, whereby the chip is further positioned on said end by the friction between said chip and said material during introduction.

Claims

1. A method of producing a rod RFID tag, comprising: providing a rod having a magnetic core, a cylindrical shape, and two distal ends; winding a wire around said magnetic core to form an antenna; positioning at one of said two distal ends of said rod where said wound wire ends terminate, an entire chip at a first position in longitudinal extension beyond the end of said rod; bonding said wire ends to contacts of said chip; displacing said bonded chip to a second position parallel with end of said rod and partially extending over one of said distal ends of said rod; and introducing said magnetic core with said wire and said chip in an encapsulating means containing a stabilizing material, whereby said chip is further displaced to a third position on said end of said rod closer to said wire winding by the friction between said chip and said stabilizing material during introduction and held in said third position by said stabilizing material.

2. The method as defined in claim 1, wherein said cylindrical shape of said rod is symmetrical in regards to its main axis.

3. The method as defined in claim 1, wherein said bonding of said wire ends to said chip contacts is made by direct bonding.

4. The method as defined in claim 1, wherein said displacing of said bonded chip on said end of said rod is made by a radial and longitudinal movement.

5. The method as defined in claim 1, wherein the method further comprises: closing said encapsulating means.

6. A tag produced by the method of claim 1.

7. The tag as defined in claim 6, wherein said magnetic core is a ferrite core.

8. The tag as defined in claim 6, wherein said encapsulation means is a glass tube.

9. The tag as defined in claim 6, wherein said stabilizing material is a resin.

10. The tag as defined in claim 6, wherein said stabilizing material is an epoxy.

11. The method as defined in claim 1, wherein the step of introducing said magnetic core with said wire and said chip in an encapsulating means comprises aligning said core, wire and chip with said encapsulating means.

12. The method as defined in claim 11, further comprising using a sliding tool for aligning said core, wire and chip with said encapsulating means.

13. The method of claim 12 further comprising vibrating said sliding tool.

14. A method of producing a rod RFID tag, comprising: providing a rod having a magnetic core, a cylindrical shape, and two distal ends; winding a wire around said magnetic core to form an antenna; positioning, at a first position in full longitudinal extension, an entire chip at one of said two distal ends of said rod where said wound wire ends terminate; bonding said wire ends to contacts of said chip; displacing said bonded chip to a second position partially extending over one of said distal ends of said rod; and introducing said magnetic core with said wire and said chip in an encapsulating means containing a stabilizing material, whereby said bonded chip is further longitudinally moved along said end of said rod by the friction between said chip and said stabilizing material during introduction to a third position and held in said third position by said stabilizing material, wherein said bonded chip is in frictional communication with said rod and said stabilizing material.

15. A method of producing a rod RFID tag, comprising: providing a rod having a magnetic core, a cylindrical shape, and two distal ends; winding a wire around said magnetic core to form an antenna; positioning a chip at a first position, said first position defined at one of said two distal ends of said rod where said wound wire ends terminate, and wherein said entire chip is beyond the end of said rod; bonding said wire ends to contacts of said chip; displacing said bonded chip to a second position parallel with the end of said rod and partially extending over one of said distal ends of said rod; and introducing said magnetic core with said wire and said chip in a glass tube containing a stabilizing material, whereby said chip is further displaced to a third position to form a loop in the ends of said wire.

16. The method as defined in claim 15, wherein said cylindrical shape of said rod is symmetrical in regards to its main axis.

17. The method as defined in claim 15, wherein said bonding of said wire ends to said chip contacts is made by direct bonding.

18. The method as defined in claim 15, wherein said displacing of said bonded chip on said end of said rod is made by a radial and longitudinal movement.

19. The method as defined in claim 15, wherein the method further comprises closing said glass tube.

20. The method as defined in claim 15, wherein the step of introducing said magnetic core with said wire and said chip in a glass tube comprises using a vibrating tool.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be better understood by a detailed description of different exemplary embodiments and from the drawings which show:

(2) FIG. 1 illustrates a side view of a tag produced according to present invention in a first state,

(3) FIG. 2 illustrates a side view of a tag produced according to present invention in a second state,

(4) FIG. 3 illustrates a side view of a tag being introduced in an encapsulating means according to present invention,

(5) FIG. 4 illustrates a side view of a tag produced according to present invention in a final state,

(6) FIG. 5 illustrates a block-diagram of the process according to the invention.

DETAILED DESCRIPTION

(7) An idea of the present invention is to take advantage of the small size of the chip to place it in a free space without specifically shaping the rod forming the magnetic core. Accordingly, the core has a simple and pure cylindrical shape not necessitating some additional shaping steps as in the prior art. This saves time and material (and is therefore cheaper). In addition, this also avoids positioning constraints linked to the shape of the magnetic core as in the prior art. There is no need any more to hold it in a certain known position to ensure that the chip is placed in the space provided in the core as in U.S. Pat. No. 7,825,869 and US 2011/0259965 for example.

(8) Further, the present invention takes advantage of the presence of stabilizing material (for example epoxy or any other suitable material) in the encapsulating means (for example a glass tube) to displace, for example push, the chip in its proper final position when introducing the tag in the encapsulating means which is a particularly advantageous production step as will be understood in the following description and with reference to the drawings.

(9) In the method of producing a rod RFID tag according to the invention (see FIG. 1), the method comprises firstly the step of providing a magnetic core 1 having a cylindrical shape and two end 1′, 1″. Then, the next step is typically the winding a wire around the core 1 to form an antenna 2. Once the winding is finished, there remain two ends 3 of the wire used to produce the antenna that will be connected to the chip, as explained later hereunder.

(10) In the next step, one positions a chip 4 at one of the ends 1′, 1″ of the rod 1 in longitudinal extension of the rod, as is known in the art. Of course, this is done at the end of the rod where the wound wire ends 3 terminate. The wire ends 3 are then bonded to the chip 4 contacts in order to form a basic RFID rod tag.

(11) The bonding process used can be of any type, as is known in the art, for example direct bonding or from the prior art cited above.

(12) The position of the chip 4 illustrated on the FIG. 1 corresponds to a standard product configuration as produced in the state of the art.

(13) In regards to the present invention, once the chip is bonded, it is then displaced from its position in longitudinal extension of the rod illustrated in FIG. 1 in a second position partially over one end 1′ or 1″ of the rod 1 as illustrated in FIG. 2. This configuration is an intermediate one as the basic RFID rod tag must still to be put into an encapsulation as will be described now.

(14) To carry out this step, one uses a sliding tool 5 (see FIG. 3) in which the rod tag is introduced, said tool allowing an alignment of the rod with an encapsulation means 6, for example a glass tube 6. As illustrated in FIG. 3, the rod tag is in the state of FIG. 2, with the chip 4 partially placed on one end 1″ of the rod 1. Advantageously, small vibrations could be applied to the tool 5 in order to facilitate the sliding down of the rod tag.

(15) Since the encapsulating means 6 contains a stabilizing material 7, for example en epoxy resin, the chip 4 is pushed backwards with respect to the introduction direction (see arrow in FIG. 3) and further positioned over said end 1″ by the friction between the chip 4 and the stabilizing material during introduction, thus placing the chip in its final position on the rod 1.

(16) This ideal final position of the chip 4 relative to the rod 1 is illustrated in FIG. 4. The chip 4 is fully pushed toward the coil windings 2 and fit perfectly the space over the rod end 1″. In this case naturally, the antenna 2 has be manufactured such that the length of the free end 1″ of the rod match the size of the chip 4.

(17) Another advantage of moving the chip 4 toward the coil winding is to create a loose loop with the wire ends that reduce the mechanical tensions/stresses to the connections to the chip. This increases drastically the durability of the product.

(18) Finally, the encapsulation means, for example a glass tag is closed to form the final RFID tag.

(19) Accordingly, the method of the present invention is very simple since it may be used with current devices, does not imply the fabrication of a specific rod and uses present materials (typically the stabilizing material) to form the final product in an efficient way.

(20) As indicated previously, any bonding technique may be used, the bonding of the wire ends to the chip contacts is made by direct bonding or any other equivalent technique.

(21) The stabilizing material may be of any type as known in the prior art: a resin such as epoxy resin or any other suitable equivalent material.

(22) Preferably, to optimize the characteristics of the tag, the rod has a shape (in particular the ends of the rod) that conforms to the shape of the encapsulation in order to able to insert the biggest (i.e. longest) rod possible in the encapsulation. The positioning of the chip 4 on the rod 1 allows this optimization of the size of the rod to the encapsulation, the rod being generally in its simplest form (cylindrical).

(23) Of course, all the embodiments described herein are to be regarded as illustrative examples and not in a limiting manner. Modifications are possible within the scope of the present invention, for example by use of equivalent means.