GB2129746A - Applying information to articles eg tyres - Google Patents

Abstract

Information is applied to the bead wire (17) of a tyre by permanently magnetising selected parts of the wire. The information may identify the operator who produced the tyre and the date of manufacture. A unique serial number of the tyre may be applied to the bead wire.

Description

SPECIFICATION Applying information to an article This invention relates to a method of applying information to an article.

The invention has been conceived as advantageously applicable to a tyre incorporating at least one bead wire of magnetic material, but may be applied to articles generally subject only to the practicality of applying the invention thereto as will be apparent from the following description.

The term 'magnetic material' (and derivatives thereof) is used herein in a generic sense to refer to any material capable of being permanently magnetised.

The term 'permanently magnetised' (and derivatives thereof) is used herein to describe material which is magnetised and which will retain its magnetism under all normal conditions of use.

According to one aspect of the invention, there is provided a method of applying information to an article wherein encoded information is applied in the form of permanent magnetisation to at least one portion of magnetic material (as herein defined) incorporated in the article.

Such a portion may be present in the article in any event, that is it may be present in consequence of performing some structural or functional duty in the article apart from the requirement to carry magnetically applied encoded information, but if no such suitable portion would otherwise be present then the method would entail provision of such a portion in the article for the purpose of carrying the encoded information.

The portion of magnetic material may be provided at a position on the article where it will retain its magnetism under all normal conditions of operation or duty to which the article is subjected when in use.

Said portion may thus be advantageously concealed (to minimise risk of unauthorised magnetic tampering and/or other damage) beneath the exposed surface of the article, preferably at a depth such that it remains concealed throughout the service life of the article.

Where said article is a tyre, the or each such portion may, for example, comprise a portion of a bead wire of magnetic material lying beneath the outer surface of the tyre adjacent to an inner rim of the tyre.

Most tyres are manufactured with two such bead wires, one bead wire being located within each inner rim, and an important merit ofthis method regarding its use to apply information to such tyres is that such tyres do not have to be modified to permit this method to be used. The bead wires of such a tyre are generally circular, and each bead wire forms a loop extending continuously all round its respective inner rim, beneath the outer surface of the tyre. Most such bead wires are presently made of steel, but this invention is not of course restricted to tyres having bead wires made of steel.

A further such merit of this method is that it does not in any way reduce the strength of the tyre and so, in this respect is superior to, for example, processes in which information is applied to a tyre by branding the tyre's side walls.

In any article to which the invention is applied, successive areas of such a portion of magnetic material may be magnetised in accordance with a code to represent respective bits of the encoded information. A Gray code may, for example, be used to encode the information. The term 'bit' is used in this specification in a generic sense which covers the case where three states (North magnetic polarity, South magnetic polarity, or unmagnetised) are possible and is not restricted simply to a conventional binary code entailing only two possible states.

Additionally there may be used for encoding information different magnetic pole strengths which may be used to represent different information. To assist correct reading of the information, there may be one or more reference spots where the magnetic pole strength has a predetermined value which is the same in a number of tyres. Additionally or alternatively, differences in the lengths of magnetic poles or in the gaps between adjacent magnetic poles may be varied to represent different information. In the case of magnetic poles present in a tyre bead, we mean by the length of a pole or the length of a gap between adjacent poles that dimension which extends circumferentially of the tyre.

Where, for example, said portion is a portion of a bead wire of a tyre, each said area may be magnetised in a direction perpendicular to the central, longitudinal axis of said portion so that the side of the portion nearest to an outwardly-facing (i.e.

facing away from thetyre) wall ofthe inner rim in which the portion is located presents a succession of areas which may each be either magnetised with a North magnetic polarity, magnetised with a South magnetic polarity or unmagnetised, as necessary to represent the encoded information.

The encoded information may be applied to an article by magnetisers having a plurality of fixedposition magnets, and any such magnets which are not required in order to apply a given piece of encoded information may be dormant or ineffective while that piece of encoded information is being applied.

One or more of said magnets may be activated by a key switch, an operator using a key to activate said key switch, said key having a shape representing (and capable of conveying) data, said magnets consequently applying encoded information representing said data, read from the key, to the article.

One or more of said magnets may be activated by edge switches which may be set by the operator, said switches being used to activate appropriate magnets in order to apply certain pieces of encoded information to the article.

At least one group of one or more of said successive areas may have a character unique within said portion and may be used as a marker. In order to facilitate reading (see later) of encoded information which has been applied as herein described to such a portion, a first such group and a further such group, said further such group having a character different from that of the first such group, may be used to indicate to a sensing device and any associated equipment (see later) the start and stop respectively of the encoded information present on that portion. The start spot may, for example, be distinguished by being larger than other areas or groups of areas.

One or more of the successive areas may be used, if desired, as an error checking spot which represents encoded information of a unique character within the or each portion of magnetic material to which information is applied and which produces a known signal in a correctly-operating sensjng device used for reading (see later) encoded information applied to the article, thus enabling correct operation of a sensing device and/or any associated equipment to be verified.

Remaining successive areas may be used to represent data.

Said data may, for example, comprise a selection from the following: unique serial number, calendar date, day number, run number, shift number, identity of manufacturer, identity of plant, machine number, identity of operator (e.g. clock number), article type, and (if approp riate) article safety rating.

When a unique serial number is represented by magnetisation of a portion of magnetic material in an article, a separate record of selected data pertain ing to that article associated with the serial number may be maintained, for example in a computer memory. It may prove very useful to record, in succession on such a portion, a calendar date on which work is carried out on an article and the clock number of an operator carrying out that work. This work may comprise, for example, one or more of the processes of the initial making, subsequent moulding, and later re-moulding of a tyre, and different portions of a bead wire of that tyre may be used individually as sites for retaining encoded information relating to each of these processes individually, this encoded information remaining in the tyre for life.

Alternatively, a unique serial number may be applied to the bead wire and data concerning the manufacturing process may be associated with that serial number in a computer memory. During later stages of the manufacturing process or during remoulding, the serial number of a particular tyre could be identified by means of an appropriate reader and data concerning the remoulding or later processes of manufacture could be recorded in the computer memory in association with the serial number. This procedure would reduce the amount of data held in the tyre bead.

It may prove useful to arrange that all magnetised areas of any given portion have a common magnetic polarity. For example, said different portions of the bead wire may be distinguished from each other by using a scheme of applying data wherein data regarding the initial making of a tyre is applied to a first such portion, each of the areas of said first such portion being either magnetised with a North magnetic polarity or left unmagnetised, and data regarding consecutive later processes is applied to consecutive further portions, each of the areas of these further portions being either magnetised with a South magnetic polarity or left unmagnetised. Any obvious variation of this scheme may, of course, be used, and areas of magnetic polarity opposite to that of other magnetised areas of a portion may be used as markers if desired.

It will be appreciated that as soon as information has been applied to an article by the above method, that article is significantly different from any articles which were previously available.

Thus, according to a second aspect of the invention, we provide an article comprising a portion of permanently magnetised magnetic material presenting a pattern of magnetic poles representing encoded information. Where said article is a tyre, said portion of permanently magnetised magnetic material may comprise a portion of a bead wire of the tyre.

According to a third aspect of the invention, we provide a method of reading encoded information on an article, said encoded information having been applied to the article by the method described above, wherein relative motion is caused to take place between a sensing device and the portion carrying the encoded information, said sensing device being separate from the article but being positioned close to said portion for the purpose of reading said encoded information, said relative motion causing signals representative of the encoded information to be generated in said sensing device.

Said sensing device may comprise a search coil and a magnetically susceptible component.

Said magnetically susceptible component is responsive to the strength of any magnetic field into which it is introduced and is used to enhance the response of the search coil to variations of magnetic field strength in the vicinity of the or each said portion caused by the presence, in the or each said portion, of areas having different magnetisation.

Said magnetically susceptible component may, for example, be made of a ferrite or some other suitable material.

Said signals may be in the form of a current and/or a voltage in said coil. Signals of opposite electrical polarity may be induced in said coil by relative motion between the sensing device and areas of opposite magnetic polarity of said portions.

Said sensing device may be hand-held, or, if desired, may be supported by some other means.

Said signals may be read, for example by level sensing for digital spots or analogue sensing for variable strength spots, using a micro-computer system. This micro-computer system may also be used to interpret said signals.

In order to read encoded information which has been applied for example to a tyre by a method as herein described, one of the following procedures may, for example, be used: (i) the tyre may be rotated either clockwise or anti-clockwise at an appropriate speed so that the magnetic material such as the bead wire ofthe tyre, to which encoded information has been applied, moves past a substantially stationary sensing device located close to the part of the tyre containing the magnetic material, such as close to the outwardly facing wall of the inner rim of the tyre containing the bead wire; or (ii) a sensing device may be moved circumferentially of the tyre at an appropriate speed along and close to the part of the tyre containing the magnetic material, such as close to the outwardly-facing wall of the inner rim of the tyre containing the bead wire to which encoded information has been applied, while the tyre remains substantially at rest; or (iii) the tyre and reader may both be at rest with a head or heads of the reader placed in a predetermined location relative to the tyre to read data from the tyre bead by means of a number of search coils subjected to a pulsed search field.

Procedures (i), (ii) and (iii) may of course be straighfforwardly modified for use with an article other than a tyre.

One embodiment illustrating certain aspects of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a simplified diagrammatic cut-away perspective view of a typical tyre having bead wires; Figure 2 is a side view of a portion of a bead wire of the tyre shown in Figure 1; and Figure 3 is a side view of a key which may be used to apply operator-related encoded information represented by the shape of the key to a section of the portion shown in Figure 2.

Referring to Figure 1 of the drawings, an entirely conventional tyre 10 has a surface comprising an outwardly-facing layer 11 and an inwardly-facing layer 12, said outwardly-facing and inwardly-facing layers being formed in one piece. The tyre is provided with a moulded tread 13, side walls 14 and inner rims 15, each inner rim 15 having an outwardly-facing wall 15fand an inwardly facing wall 15r.

Walls 1 stand 15r of each inner rim form the sides of a continuous circular passage 16 lying within, and extending all round, that inner rim completely beneath said surface of the tyre. Each passage 16 is occupied by a continuous multi-core circular bead wire 17 in the form of an endless loop. The bead wires are typically made of a material such as steel, which is magnetic (as herein defined), and helpto preserve the shape of the tyre and to retain the tyre on the wheel of a vehicle.

Figure 2 shows a side of a portion 20 of bead wire 17, said side facing an adjacent wall 1 5f of an inner rim 15, and indicates an arrangement of areas or groups of areas to which encoded information has been applied in accordance with the invention. The area or areas of section 21 is or are magnetised so as to provide a start spot, the areas of section 22 are magnetised so as to represent a calendar date, the areas of section 23 are magnetised so as to represent an operator's clock number, the area or areas of section 24 is or are magnetised to provide an error checking spot, and the area or areas of section 25 is or are magnetised to provide a stop spot.

Alternatively, one area only of the bead wire may be used, this area being magnetised to represent a unique serial number of the tyre.

Portion 20 is shown in Figure 2 to have a certain length and to turn through a corresponding angle from end to end. Using areas which are generally each of a common standard length, the length of bead wire required for a portion and, of course, the corresponding angle through which that portion turns from end to end, will in practice depend upon the amount of encoded information to be stored by that portion. Any convenient standard length may be chosen for the areas, so that a given amount of encoded information may be accommodated on any of numerous convenient lengths of bead wire.

Portion 20 has a central longitudinal axis which is indicated at 26.

Figure 3 shows a key 30 having a head/hand-grip 31 incorporating a hole 32. The key has a shaft 33 with an edge 34 on which irregularities 35 are provided. On any given key, these irregularities 35 are positioned so that, when the key is inserted into a key switch by an operator, they convey the clock number of that operator to magnetisers and/or tyre making, moulding or re-moulding apparatus, via the key switch. The magnetisers apply this clock number, read from the key, in encoded form to section 23 of portion 20. Different operators with different clock numbers have keys with irregularities in different positions, so that the key of any given operator has irregularities which represent (and convey to the apparatus) the clock number of that operator.

Alternative devices bearing information which identifies an operator may be used. For example, each operator may have a bag bearing information in magnetically encoded form. An appropriate reader would be provided, in place of the key switch, to read this information and transmit the information to apparatus for applying the information to the tyre.

Magnetising apparatus of generally known form may be used for magnetising the selected areas of the bead wire 17. Apparatus comprising a number of magnets, selected ones of which are activated in accordance with the information which is to be applied to the tyre may be used. Alternatively, a single magnet may be used, this magnet being moved relative to the tyre and activated at selected positions. Magnetic poles may be produced on the bead wire at predetermined positions such that the spaces between adjacent poles are uniform. If required, a data-identification pole may be produced adjacent to each pole which represents data, the data-identification poles being of opposite polarity to the poles which represent data. The lengths of poles, measured circumferentially of the tyre, may be varied to represent different information and/or the lengths of spaces between adjacent poles may be varied for the same purpose.

It will be appreciated that although the above description includes examples which relate to applying encoded information to a tyre and also to reading such encoded information on a tyre, the methods of this invention may be used to apply encoded information to any article and also to read such encoded information.

Any article to which encoded information has been applied by one of these methods will fall within the scope of this invention.

It will be appreciated that conventionally known magnetic recording tape is provided specifically for the purpose of recording information impressed magnetically onto the tape, whereas this invention relates to applying encoded information to an article intended mainly for some purpose other than storing or carrying said encoded information.

Claims (20)

1. A method of applying information to an article wherein encoded information is applied in the form of permanent magnetisation to at least one portion of magnetic material (as herein defined) incorporated in the article.

2. A method according to Claim 1 wherein such a portion is located at a position in or on the article where it will retain its magnetism under all normal conditions of operation or duty to which the article is subjected when in use.

3. A method according to Claim 2 wherein said article is a tyre having at least one bead wire of magnetic material (as herein defined) and the or each said portion is a portion of such a bead wire lying beneath the outer surface of the tyre adjacent to an inner rim of the tyre.

4. A method according to any one of the preceding claims wherein successive areas of such a portion are magnetised in accordance with a code to represent respective bits (as herein defined) of the encoded information.

5. A method according to Claim 4 wherein at least one group of one or more of said successive areas has a character unique within said portion.

6. A method according to any one of the preceding claims wherein encoded information is applied by magnetisers having a plurality of fixed-position magnets.

7. A method according to any one of Claims 1 to 5 wherein encoded information is applied by a magnetiser having a magnet which undergoes movement relative to the article to magnetise the portion of magnetic material at positions which are spaced apart by pre-selected distances.

8. A method according to Claim 6 or Claim 7 wherein said magnets or magnet are or is activated by a device bearing encoded information identifying an operator, which information is applied to the article.

9. A method according to Claim 6 or Claim 7 wherein said magnets or magnet are or is activated by a key switch, an operator using a key to activate said key switch, said key having a shape representing (and capable of conveying) data, said magnets consequently applying encoded information representing said data, read from the key, to the article.

10. An article to which information has been applied according to the method described by any one of Claims 1 to 9.

11. An article comprising a portion of permanently magnetised magnetic material (as herein defined) presenting a pattern of magnetic poles representing encoded information.

12. An article according to Claim 11 wherein said article is a tyre and said portion of permanently magnetised magnetic material comprises a portion of a bead wire of the tyre.

13. A method of reading encoded information on an article, said encoded information having been applied to the article by the method of any one of Claims 1 to 9, wherein relative motion is caused to take place between a sensing device and the portion carrying the encoded information, said sensing device being separate from the article but being positioned close to said portion for the purpose of reading said encoded information, said relative motion causing signals representative of the encoded information to be generated in said sensing device.

14. A method according to Claim 13 wherein said sensing device comprises a coil and a magnetically susceptible component.

15. A method according to Claim 13 or Claim 14 wherein said sensing device is hand-heid.

16. A method according to any one of Claims 13 to 15 wherein said signals are read and/or interpreted using a micro-computer system.

17. A method of applying information to an article substantially as hereinbefore described and/ or as illustrated in the accompanying drawings.

18. An article to which information has been applied by a method substantially as herein before described and/or as illustrated in the accompanying drawings.

19. A method, substantially as hereinbefore described and/or as illustrated in the accompanying drawings of reading encoded information on an article, said encoded information having been applied to said article by a method of applying information substantially as hereinbefore described and/or as illustrated in the accompanying drawings.

20. Any novel feature or novel combination of features described herein and/or illustrated in the accompanying drawings.