System for the Identification of Containers, Notably Gas Cylinders

The present invention relates to a system for the identification of containers, notably gas cylinders.

There are known ways of locating, identifying and labelling items such as gas cylinders in gas-filling plants. The numbers affixed to these cylinders can be used to keep track of them during the operations that precede or follow their being filled in the plant. This tracking or follow-up is done notably during cylinder-sorting operations, when the cylinders are unloaded from carrier trucks, when they are filled and then when they are packed in delivery racks or cases, and also when the delivery orders are being prepared as well as when the cylinders are delivered to the customers.

To prevent the labels from being damaged or possibly detached from the cylinders during handling operations in the plant, or when they are being transported, precautions are generally taken to provide mechanical protection means on the cylinders. One efficient method of protection consists, for example, in fastening the labels to the interior of a bell-shaped part that generally encloses the tap of the cylinder. This provides the label with efficient mechanical protection against tearing and at the same time protects the tap against any accidental handling. Unfortunately, this arrangement rules out any possibility of the automatic optical reading of the inscriptions on the labels since these labels are masked by the cover provided by the tap-protecting bell. Furthermore, the fact that the bell is generally made of metal rules out any possibility of using electronic labels provided with devices that emit radioelectric waves for example, since the metal cover behaves like a screen that is opaque to electromagnetic waves.

The aim of the invention is to overcome the above-mentioned drawbacks.

To this end, an object of the invention is a system for the identification of containers shut by by a tap that is surrounded by a protective bell characterized in that said system comprises, firstly an electronic label provided with a device for emitting electromagnetic waves coupled to a memory and, secondly, a data terminal coupled to a detachable read/write head comprising a transceiver of electromagnetic waves that can be introduced, as desired, into the tap-protecting bell to transmit information elements between the memory of the electronic label and the data terminal.

The main advantages of the invention are, firstly, that it enables reliable reading of the information elements contained in the labels, whatever the nature of the rough treatment and mishandling undergone by the cylinders during their transportation or during their packaging and, secondly, that it provides a solution that is perfectly suited to the dynamic labelling of gas cylinders for example.

Other features and advantages of the invention shall be seen here below from the following description, made with reference to the appended drawings, of which:

FIG. 1 shows a system for the identification of containers according to the invention;

FIG. 2a shows an embodiment of a ring wherein the ring has a coil embedded therein which substantially matches the shape of the ring;

FIG. 2b shows another embodiment of a ring wherein the ring has a riveting type of closing device;

FIG. 2c shows another embodiment of a ring wherein the ring has a reinforced zone for housing an electronic label;

FIGS. 3a and 3b show two embodiments respectively of the electronic module of the label and of the read/write head forming the system according to the invention;

FIGS. 4a and 4b show two possible modes of introducing the read/write head into the protective bell of the tap.

The cylinder-identification system according to the invention, shown schematically in FIG. 1, essentially comprises an electronic label 1, in the form of a small-sized patch supported by a ring 2 surrounding a tap 3 used to close a container 4 which, in FIG. 1, takes the form of a gas cylinder. The ring 2 is fixed to the bottom of a protective bell 5 of the tap 3. This system also includes a data terminal 6 that has the role, by means of a read/write head 7, of recognizing the presence of the label, identifying it and, if necessary, of recording information elements therein.

The label 1 and the read/write head 7 are coupled together electromagnetically, firstly by means of a single coil 8 that is embedded in the body of a ring 2 and electrically connected to the label 1 and, secondly, by means of two ferrite coils (not shown) placed in the read/write head 7. The coupling takes place when the read head 7 and the ring 2 are placed substantially in a position of facing each other, as shown for example in the diagram of FIG. 2a. This figure shows a label 1 formed by an electronic module 100. The electronic module is coupled to the coil 8. The module and the coil are both embedded inside a plastic resin forming the ring 2. In this embodiment, the shape of the coil substantially matches that of the ring 2 in order to provide a maximum surface area of electromagnetic radiation. In a preferred variant, the coil 8 has, for this purpose, strands that are stretched out on the external and internal peripheries of the ring. These strands get looped with one another in such a way that the surface of the crown formed by the ring constitutes the useful surface area of transmission of the electromagnetic waves. The antenna thus constituted forms a loop as illustrated by the embodiment of FIG. 2a.

For the transmission of information elements between the label 1 and the read head 7, it is therefore preferable that this head 7 should be positioned so as to be facing the inner surface of the coil 8, before the crown.

The ring is detachable and may be installed on a stock of cylinders not yet been provided with such a system. Indeed, to enable the ring to be positioned around the tap 3, this tap is slotted by means of a slot 9. It has a clip-on or riveting type of closing device 10, positioned as illustrated by the embodiment of FIG. 2b. This device 10 has two inside recesses 11 and 12 designed to overlap in order to form catches that close the slot 9. To enable the ring 2 to be easily positioned around the tap 3, the ring 2 has a flexible region 14, diametrically opposite the slot 9, that permits the ring to be subjected to twisting or torsion in this region. This flexible region is obtained, for example, by giving an appropriate size to the section of the ring in the region 14, notably by reducing its dimensions. It is also possible to hollow out the ring at the position of this flexible region. By contrast, at one of its ends close to the slot 9, the ring 2 has a reinforced zone 15 set aside for housing the label 1. Reference may be made to the drawing of FIG. 2c for a clearer picture of an embodiment of the ring 2 having these structural details. Indeed, in a preferred embodiment, the electronic module 100 is a chip bonded to a printed circuit 36, this chip being covered with a drop of protective resin. The reinforcement zone 15 is obtained, for example, by placing a rigid cap above the chip. The cap may be made of metal. The contact wires 37 are connected to the coil 8. The wires 37 are connected to the contact wires 38 of the chip through the printed circuit 36.

The introduction of the read/write head into the bell 5 in order to transmit information elements between the data terminal 6 and the label 1 takes place according to the modes shown in FIGS. 3a and 3b. In the mode of introduction shown in FIG. 3a, the read head is introduced by the upper aperture 16 of the bell 5. In the mode shown in FIG. 3b, the read/write head 7 is introduced through a side window 17 made in the very body of the bell 5.

The label comprises, in the manner described for example in the French patent No. 2 623 311, an electronic module formed by logic and analog circuits and by storage circuits connected to the coil 8. The analog circuits 18 firstly pick up the electromagnetic energy given by the read/write head to supply the internal circuits of the label. Secondly, they carry out the reception of the signals that are sent by the read/write head and picked up by the coil 8. The logic circuits essentially comprise a decoder 19 to decode the signals transmitted by the read/write head 7 and to apply them by means of a shift register to the data inputs of an EEPROM memory 20, of the type marketed under the reference NM9346 by the US-registered firm National Semiconductor for example, and an encoder 21 to convert the data elements read in the EEPROM memory 20 into analog signals in order to transmit them to the read/write head 7.

The read/write head comprises a microprocessor 23 coupled, firstly, to the data terminal 6 by means of an interface circuit (not illustrated) and, secondly, to an electromagnetic transmission device 24 and electromagnetic reception device 25 respectively comprising a transmission encoder 26 coupled to a modulation stage 27 and a demodulator 28 coupled to a decoder 29. The antenna 30 is constituted by a ferrite coil. The entire system is placed at the end of a flexible cable provided with a grip to make it easier to insert the read/write head into the bell. The flexible cable has a length that may vary depending on whether it is designed to be installed in a fixed station or a portable terminal. Naturally, to obtain reliable operation of the system, the read head should preferably be placed so as to be sufficiently close to the label.