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Title:
MARKING METHOD
Document Type and Number:
WIPO Patent Application WO/2019/186609
Kind Code:
A1
Abstract:
Marking method, according to invention, is characterized by a turning process with which turning an encoding information for identification and traceability of shafts and gear wheels used for propulsion motion and for transmission of motion, as well as identification and traceability of metals used for their construction. Said turned encoding information comprises a plurality of encoded engravings, turned at 360 ° around circumferential surfaces of said shafts and gear wheels, each of which is intercalated from an encoded space, turning the same simultaneously to the same phase of their turning process.

Inventors:
VITALE, Alberto (via guglielmo marconi 11, Termoli, 86039, IT)
Application Number:
IT2019/050063
Publication Date:
October 03, 2019
Filing Date:
March 23, 2019
Export Citation:
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Assignee:
PAOLINO, Incoronata (via guglielmo marconi 11, Termoli, 86039, IT)
VITALE, Alberto (via guglielmo marconi 11, Termoli, 86039, IT)
International Classes:
G06K19/06
Foreign References:
US20160042261A12016-02-11
CN104924771A2015-09-23
US20030121980A12003-07-03
US4989483A1991-02-05
US4822987A1989-04-18
US20070278192A12007-12-06
EP0817108A21998-01-07
US20160042261A12016-02-11
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Claims:
CLAIMS

1. Marking method for identification and traceability of shafts and gear wheels used in the propulsion motion and in the transmission of motion, as well as for the identification and traceability of the metals used for their construction, characterized by a turning process with which turning an encoding information, comprising a plurality of encoded engravings, turned 360° around their circumferential surfaces, each of which intercalated from a space also encoded. Said method, includes programming of a turning machine program, for a CNC lathe, containing a plurality of instructions useful for executing the turning cycle of the alternating succession of said encoded engravings and of said encoded spaces, loading the same within the turning machine program already employed by said CNC lathe for turning said shafts and gear wheels, so that with a single turning cycle the rough pieces are turned and simultaneously said information encoding is turned 360° around their turned circumferential surfaces.

2. Marking method according to claim 1 , wherein said turned engravings and said spaces at the same intercalated are of variable dimensions.

3. Marking method according to claim 2, wherein to each variable dimension of said engravings to be turned and to each variable dimension of said spaces intercalate to the same an alphanumeric code is associated according to a predetermined coding model.

4. Marking method according to claim 1 , wherein the alternating succession of said encoded engravings and of said encoded spaces identifies the information contained in said turned encoding.

5. Marking method according to claim 1 , wherein said turning instructions of said program are labeled with alphanumeric codes coinciding with those associated to the corresponding engravings to be turned and to the corresponding spaces intercalate to the same.

6. Marking method according to claim 5, wherein said turning machine program includes a plurality of program conditioned jumps to said turning instructions labeled with said alphanumeric codes.

7. Marking method according to claim 6, wherein said program conditioned jumps to said turning instructions labeled are conditioned from a plurality of logical conditions whose values consist of alphanumeric codes corresponding to those of the labels of said turning instructions.

8. Marking method according to claim 7, wherein said turning machine program includes a plurality of settable parameters within which to enter the alphanumeric codes constituent values of said logical conditions.

9. Marking method according to claims 7 and 8, wherein said logical conditions include the following conditions: according to the alphanumeric codes entered into said settable parameters said turning program will execute program conditioned jumps to the turning instructions labeled with the alphanumeric codes corresponding to those entered into said settable parameters.

10. Marking method according to claim 9, wherein according to the alphanumeric codes entered into said settable parameters it will be turned the alternating succession of encoded engravings and encoded spaces corresponding to the encoded information to be marked.

1 1. Marking method according claim 10, wherein the detection and decoding of said alternating succession of said encoded engravings and said encoded spaces it is performed with optical instruments of industrial vision for not contact measurements.

Description:
MARKING METHOD

DESCRIPTION

TECHNICAL FIELD

The present industrial invention relates the technical field of metal marking and in particular marking, by a turning process, an encoding information for identification and traceability of shafts and gear wheels used for propulsion motion and for transmission motion, as well as the identification and traceability of metals used for their construction.

BACKGROUND ART

To date, various methods and techniques have been claimed for marking encoding information on the surfaces of metal components having circumferential surfaces.

US 4822987, in:“METHOD AND APPARATUS FOR PROVIDING FUEL ROD IDENTIFICATION TO PERMIT TRACEABILITY DURING MANUFACTURE AND USE”, claims marking of an encoding information as a bar code around the surfaces of cladding tubes for nuclear fuel rods, marking said tubes with a laser marking technique removing material by localized fusions or vaporization on their circumferential surface.

Detection of information contained in bar code marked with this laser engraving marking technique takes place by exploiting the optical reflection of marked surfaces.

Still, US20070278192, in:“SYSTEM AND METHOD FOR LASER-ENCODING INFORMATION ON HIDRAULIC RODS”, claims marking an encoding information similar a bar code around circumferential surfaces of hydraulic rods. With said method a laser annealing marking technique on the surface of said hydraulic rods is employed.

Finally, EP0817108, in:“METHOD FOR PRINTING BAR-CODES”, also claims the marking of an encoding information, such as a bar code, using laser annealing marking technique of circumferential surface of nuclear fuel cladding tubes.

With said two laser annealing marking techniques on the surfaces of components having circumferential surfaces claimed by: US20070278192 and EP0817108, the energy of laser beam heats the surface of components to temperatures that cause the thermal degradation of material leaving an oxide layer and modifying the reflection characteristics of heated portion of surface.

Detection of information contained in said coding marked with said laser annealing marking technique takes place by exploiting optical reflection caused by oxide layers which are formed following the heating temperatures of surface layer.

It’s evident, that the components on which the code claimed by aforementioned laser marking methods is marked undergo a transformation process different from that to which shafts and gear wheels are subjected such as those object of present method.

In fact, transformation of components claimed by US4822987, US20070278192 and EP0817108, starts from slabs of raw material that will be melted at high temperatures and then they will be laminated making components already finished and ready for use where to mark encoding information, such as , those claimed by U4822987, such as the serial number of nuclear fuel rod and quality of content loaded into it.

Said encoding information, however, is not marked along the transformation process of said tubes, but along the assembly process of the same, i.e. at their end user.

In fact, confirming this, US4822987, claims two phases of process in which the information is marked.

First phase is performed before the bar is loaded with nuclear fuel, while the second phase occurs after the same has been loaded of nuclear fuel.

It is evident that US4822987, US20070278192 and even less EP0817108 do not claim and will never be able to claim marking information regarding characteristics of said tubes and rods used by them, such as those of metals used for their construction, as they are not marked within production process where their transformation takes place, but along the process where they are assembled.

Precisely for this reason, aforementioned laser marking techniques represent a limit for marking said information encodings on surfaces of said shafts and gear wheels, since they undergo a different transformation process than one to which components claimed by said laser marking techniques are subjected.

In fact, said shafts and gear wheels during the various operations of their transformation process that from raw components will transform them into finished components are also subjected to a heat treatment process.

Therefore, if such information were marked using aforementioned laser marking methods before they are subjected to heat treatment process, the same phases of carbonitriding, cementing, tempering and shot blasting, typical of said heat treatment process would cover both optical reflections produced by superficial incisions made with laser marking technique for engraving and oxide layers caused by laser annealing marking technique making their detection impossible.

While, on contrary, if marking of encoding information marked with aforementioned methods were carried out after said shafts and gear wheels had been subjected to said heat treatment process, the traceability of metals would be invalidated since information would be marked on semi-finished components in points of downstream production process compared to one where first operation of their transformation from raw components into turned components is performer, i.e. the turning process.

In addition to product and process limits described above, safety of said laser marking stations must also be taken into account, including costs of its management.

Laser equipment used for metal marking produces intense electromagnetic radiation as also described by US20070278192.

These electromagnetic radiations can present biological and collateral risks.

Said risks depend on a few factors, such as: wavelength of emitted radiation, energy power of beam and duration of its issuance.

The eye is most vulnerable organ and every type of damage due to reflection of laser beam on cornea and retina must be prevented.

If laser power is high enough exposure to beam can also cause skin damage.

Precisely for this reason, laser safety is covered by (EN) 60825 standard which requires their classification according to characteristics of beam.

This legislation is essential for all laser users and manufacturers of objects using laser sources.

Therefore, precautions must be taken by users of said laser marking stations, such as: laser should only be used in a controlled area and by qualified personnel, at entrances of areas where these laser marking stations are located, laser warning signs should be posted, the eye must be protected if there is any possibility of direct observation or a specular reflection of ray, laser beam should be terminated at the end of its useful path to ensure that danger of beam is reduced to a minimum.

One of collateral hazards, instead, concerns dispersion in the air of vaporized material, of noxious fumes and vapors, for which adequate aspiration systems must be provided.

Further process limits related to aforementioned laser marking techniques of encoding information if the same were applied to identify and trace, as mentioned, metals used for construction of said shafts and gear wheels, concern allocation of said marking stations within production processes where their transformation takes place which always sees them downstream of first phase of same, i.e. after turning operation, when by now semi-finished components are already anonymously present along processing line.

This limit, even more accentuated within automated production processes having more processing lines for mix of differentiated products, each of which comprising multiple variants of the same and which employ multiple types of raw materials with different melting castings, more production lots for each of them and more suppliers of the same, making it impossible to immediately and simultaneously mark on each type of component information regarding metals used for their construction, these information, exclusive only for that type of product and at that particular time.

Furthermore, a failure of said laser marking stations causes not only production stop of process downstream of them, but also an upstream line block avoidable only with a manual inter-operational storage of semi-finished products.

Activity that derives from this further undermines traceability process that is already uncertain in itself, since discharge and subsequent reloading of said semi finished products in line generates a logistic confusion such as to infect a little traceability that current known techniques of sector offer.

Finally, another their limit is their specialization, in fact every new product, or every significant variation of marking position on surfaces of components involves use of dedicated marking stations each with its own specificities, as claimed in US4822987 and in US20070278192 and as described in EP0817108.

Differently from what is claimed by aforementioned known methods of laser marking of encoding information, US20160042261 claims in its "STRUCTURALLY ENCODED COMPONENT AND METHOD OF MANUFACTURING STRUCTURALLY ENCODED COMPONENT" a generic method with which to mark a encoding of information on surfaces of various components, without however making it explicit.

Unfortunately, in all claims of US20160042261 there is no written evidence of type of processing method performed to which above claim can be referred, except for a generic printing method with which to mark voids on surfaces of said components.

Now, technique is also expressed through use of precise technical terms and printing term in known technique normally identifies a marking by print which badly it is combined with a turning operation with which to engrave hard metal surfaces.

However, US20160042261 describes, but does not claim, that said encoding information similar to a bar code can be marked around the circumferential surface of a rod also by manufacturing methods known as the use of a lathe, turning a series of notches around its surface.

Even here, it would have been useful to use adequate technical terms, such as: turned engravings or turned grooves instead of printing notches and voids.

Now, even if we did not want to take into consideration how much US20160042261 actually claims, but we consider only a sentence of its description, it is in any case evident to prior art that a person skilled in art is able to turn simple notches around the circumferential surfaces of finished components ready for use like a rods, but as previously wrote, US20160042261 is not explicit, nor does it claim a method which brings novelty to the known art since taking a rod or another finished component and turning around its circumferential surface simple notches it is established that this has no inventive activity.

Contrary to present invention in which a new turning method is explicitly claimed with which to turn a encoding information around the circumferential surfaces of said shafts and gear wheels and to do it simultaneously with same phase of their turning, thanks to programming of a turning machine program for CNC lathe that combines, as never before, turning instructions and encoding information data conditioning them in such a way as to simultaneously integrate, in a single turning process, the processes of productivity and traceability in a precise, repeatable, fast and reliable way.

Moreover, turning method described by US20160042261 , but in any case not claimed by it, is not capable of turning an encoding information simultaneously with the same transformation step of said rod since its method suffers from the same limitations of product and process of US4822987, US20070278192, EP0817108, described above.

Therefore, scope of protection claimed is not clear in US20160042261 in that, contrary to what is explicitly claimed in US4822987, US20070278192 and EP0817108, the same does not claim any turning method or machine that can make one think of a turning process with which to turn a encoding information, these claims are necessary to place its invention within a well-defined and circumscribed sector in order to be able to evaluate its actual inventive activity and innovative scope of its method of turning encoded information which could invalidate inventive activity of present invention.

Finally, also methods of detecting marked information claimed by US20160042261 are not adequate for detection and decoding of information marked with a mechanical turning process.

In fact, X-rays, fluoroscopy, computational tomography, electromagnetic radiation, ultrasounds, positron emission tomography and magnetic resonance images are normally used in medical field, while ultrasounds are also used in industry, but aimed at finding and identifying defects of material structure.

Contrary to invention wherein said detection and decoding takes place with optical instruments of industrial vision known for non-contact measurements normally used in manufacturing processes of metal-mechanical industries. DISCLOSURE OF INVENTION

Aforementioned product and process limits are overcome with present method by turning encoding information simultaneously with same turning phase of said shafts and gear wheels used in propulsion of motion and in transmission on motion.

Said encoding information comprises a plurality of engravings turned at 360° around their circumferential surfaces each of which intercalated by a space.

Said engravings and said spaces have variable dimensions.

An alphanumeric code is associated to each variable dimension of each of said turned engravings and to each size variable of each of said spaces intercalated to said engravings, according to a predetermined information coding model.

Said encoding information identifies and tracks said shafts and said gear wheels as well as information relating raw materials used for their construction, such as those of their melt flows, this information is useful for their identification and traceability during and after various stages of processing, assembly, logistics and use that from raw state will transform them into finished components.

This involves programming a turning machine program, for CNC lathe, in which a plurality of instructions are programmed for turning an alternating succession of said encoded engravings and said encoded spaces.

After that each of said instructions is labeled with an alphanumeric code corresponding to alphanumeric code previously associated to each of said turning engravings and to each of said spaces intercalated to the same.

Subsequently, conditional program jumps are programmed to said labeled instructions, conditioning them to logical conditions whose values consist of alphanumeric codes corresponding to those identifying said labeled instructions which in turn correspond to those previously associated with said engravings and said spaces. Again, settable parameters are programmed where to enter alphanumeric codes of conditions of said logical conditions.

Therefore, according to alphanumeric codes entered into aforementioned settable parameters said second turning machine program will execute conditioned program jumps to instructions labeled with alphanumeric codes corresponding to those entered in said settable parameters, turning said alternating succession of encoded engravings and encoded spaces in accordance with encoding pattern of information previously set.

Said turning machine program is loaded into the turning machine program already used by said CNC lathe to turn said shafts and gear wheels.

So that, with a single turning cycle that raw pieces are turned and simultaneously is turned said encoding information on 360° around their turned circumferential surfaces.

Said coded information, turned around circumferential surfaces of said shafts and gear wheels, are detected and decoded by means of industrial vision optical instruments for non contact measurements arranged along production process.

Said steps will be described in detail during the following:“BEST MODE FOR CARRYING OUT THE INVENTION” of said marking method, by a turning process, according to the invention.

Said encoding of information is turned at 360° around the circumferential surfaces of said shafts and gear wheels, therefore it is uniformly visible in same way at each point of their circumference so that it can be easily detected with said optical instruments of industrial vision.

The main objective of present invention is to guarantee immediate identification and traceability of said shafts and gear wheels as well as that of metals used for their construction already during first operation of production process of their transformation, i.e. turning process, in order to increase level of product quality and efficiency of processes entire production chain in metalworking sector overcoming limits of current known marking methods.

Advantages that invention brings to known technique are many.

First, in order of importance, is that of being able to turn, simultaneously with same turning phase of said shafts and gear wheels, an encoding information around their circumferential surfaces and to do it during first operation of production process of their transformation, where same from raw state are transformed into turned components ready for the other phases of production process.

Therefore, thanks to invention, by performing a single turning cycle, said shafts and gear wheels are turned and simultaneously encoded so as to be immediately identified and tracked.

Still, a further advantage that this invention brings is certainty of being able to accurately assess value of waste and stock of semi-finished and finished products still present in company at the end of the year.

In fact, thanks to invention, being able turning around the surfaces of said shafts and gear wheels information regarding metals used, including dates of introduction of said raw materials into manufacturing production process, it is possible to accurately trace date of their purchase by assessing their actual economic value including purchase cost and manufacturing cost at the time of inventory count.

Another advantage, deriving from invention, is that of being able to monitor quality of supplies from iron and steel industries after they have been transformed, their suppliers can be identified at any time.

Finally, further advantage that this invention offers to mechanical engineering industries is that of being practically at zero cost, since marking, by a turning process, of said encoding information is performed with use of same CNC lathes used in normal production process of said shafts and gear wheels and with machine times almost unchanged.

Method, according to invention, is however easily and validly applicable also in software programming of new CNC lathes and for construction of new types of components without having need to purchase dedicated marking stations.

Therefore, thanks to method, according to invention, mechanical engineering industries will not be forced to equip themselves with marking stations, thus obtaining a considerable saving in costs that can be found in the significant reduction in technological and management costs currently incurred to track their products, albeit with limited effects.

Said marking method, by a turning process, claimed in present invention, meets requirements of novelty and inventiveness, being new and not enclosed in state of art so far made accessible to public differentiated in a qualified way from what in the same content overcoming its normal prospects for evolution since some operations being part of a known and reproducible manufacturing process by any person skilled in the art, and a person skilled in the art means a person in possession of particular skills of known technique related to product created, have been combined in new ways and with new ones like never before.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 , illustrates upper face of a finished turning gear (10) marked with an encoding information (14) turned at 360° around (1 1 ) its circumference, comprising an alternating succession of encoded engravings (12) and encoded spaces (13).

Fig. 2, illustrates lower face (20) of same finished turning gear shown in Fig. 1 , marked with an encoding information (24) turned at 360° around (21 ) its circumference, comprising an alternating succession of encoded engravings (22) and encoded spaces (23).

Fig. 3, illustrates the side view of a finished turning input shaft (30) marked with an encoding information (34) turned at 360° around (31 ) its circumference, comprising an alternating succession of encoded engravings (32) and encoded spaces (33).

BEST MODE FOR CARRYING OUT THE INVENTION

The purposes and advantages of present marking method, by a turning process, according to invention, will be clear from following description of a preferred but not exclusive embodiment, illustrated purely by way of a non limiting example, performed on the upper face of a gear (10), as illustrated in Fig. 1.

According to aforementioned attached figure, references of which are given in round brackets, said marking method, by a turning process, includes programming of a turning machine program for CNC lathe with which to turn, simultaneously with same turning phase of said gear (10) used inside a gearbox, an encoding of information (14) at 360° around (1 1 ) turned circumferential surface of its upper face (10).

Said encoding information (14) comprises a plurality of engravings (12) of variable dimensions turned at 360° around (1 1 ) circumferential surface of said gear (10), intercalating to each of them (12) a space (13) also of variable size.

An alphanumeric code is associated with each variable dimension of each of said engravings to be turned (12) and with each variable dimension of each of said spaces (13) according to a predetermined information coding model.

Said coding (14) will identify and trace said gear (10), as well as information regarding the raw material used for its construction. For this preferred but non limiting embodiment, programming of said turning machine program comprises programming of a plurality of instructions for turning each variable dimension of each of said engravings (12) to be turned and of each variable dimension of each of said spaces (13) to be intercalated to each of the same (12).

After that each of said instructions be labeled with an alphanumeric code corresponding to alphanumeric code previously associated to each of said engravings (12) to be turned and to each of said spaces (13).

Subsequently, conditional program jumps will be programmed to said labeled instructions, conditioning them to logical conditions whose values consist of alphanumeric codes corresponding to alphanumeric identification codes of said instructions labeled in turn corresponding to those previously associated with said engravings (12) and said spaces (13).

Again, settable parameters will be programmed where to enter alphanumeric codes of conditions of said logical conditions.

Therefore, according to alphanumeric codes that will be entered within aforementioned settable parameters, said second turning machine program will perform conditioned program jumps to the instructions labeled with alphanumeric codes coinciding with those entered in said settable parameters, turning said alternating succession of said encoded engravings (12) and said encoded spaces (13) in accordance with encoding information model previously set.

In this preferred, non limiting embodiment, programming construct ISO: CASE- OF will be used for programming said conditioned program jumps to said marked instructions.

For example: syntax that will be used is as follows: CASE [logical condition] OF [val ...] GOTOF [label ...].

Therefore: if condition of logical condition contained within CASE and OF construct assumes, for example, [value n], a GOTOF jump is executed to program instruction labeled as [label n].

Therefore, according to alphanumeric codes that will be entered within aforementioned settable parameters, said turning machine program will perform conditioned program jumps to instructions labeled with alphanumeric codes coinciding with those entered in said settable parameters, turning an alternating sequence of encoded engravings (12) and encoded spaces (13) in accordance with previously set information coding model.

Below, it will be briefly described, purely by way of example, a non limiting example, of first two conditions for logical conditions to be entered in first two settable working parameters corresponding to first two alphanumeric codes, for example 3 and 5, components encoding information (14) to be turned at 360° around (1 1 ) the circumferential surfaces of said gears (10), which will be followed by two conditional program jumps to two instructions labeled with codes 3 and 5 to turn first encoded engraving (12) that will be intercalated from an encoded space (13) which will separate the second engraving that will follow, according to encoding model set.

To allow reader to understand description of following example, square brackets have been inserted in which are contained the instructions of said turning machine program and braces inside which are contained some brief explanations.

During the finishing phase of the gears (10) involved in the turning process of said encoding information (14) and after the X and Z axes have positioned themselves at the start turning height of said encoding information (14): [CASE parameter n1 ] [OF val 3] [if value of condition entered in first parameter takes value 3} [GOTOF label 3] [conditional jump to instruction with label 3 corresponding to turning of first encoded engraving (12) associated with first alphanumeric code whose geometric movement coordinates refer to the dimensions [X ...] [Z ...] to turn said engraving (12)}, then [G01 ] [linear interpolation command} [ X...] [diametral dimension value referred to its (12) depth} [Z...] [final quota value of width of its (12) internal profile}, then [G01 ] [linear interpolation command} [ X...] [return diameter value to initial portion of surface} [Z..] [final share value of width of said engraving (12)}, then [CASE parameter n2] [OF 5] [if value of condition entered in second parameter takes value 5} [GOTOF label 5] [conditional jump to instruction with label 5 corresponding to dimension of space (13) which intercalates first engraving (12) from next and which is associated with second alphanumeric code whose movement instructions refer to dimensions [X ...] [Z ... ] for its (13) execution}, then [GOO] [fast forward command} [X...] [diameter surface value} [Z...] [final share value of said space (13)}.

Turning machine program will continue with same modus operandi until end of turning of said encoding (14) around (11 ) the circumferential surfaces of said gears (10).

Subsequently, said turning machine program of said encoding information (14) is loaded into turning machine program already used by said CNC lathe for turning said gears (10).

Therefore, with a single turning cycle the raw gears are turned and simultaneously the alternating succession of encoded engravings (12) and encoded spaces (13) are turned around (1 1 ) their circumferential surfaces (10).

Then, one enters new turning program of said gears (10) and of said encoding information (14) and, positioning itself in part of program dedicated to turning of said encoding information (14), sequence of alphanumeric codes is entered within settable parameters identifiers information to be coded according to said predetermined encoding model, what values of conditions for logical conditions for execution of conditioned program jumps to turning instructions whose labels are associated with corresponding alphanumeric codes of said encoded engravings (12) to be turned and to said encoded spaces (13) to be intercalated to the same (12).

Once data has been entered into these settable parameters and confirmed, work cycle is performed, turning raw gear and simultaneously turning encoding information (14) at 360° around (1 1 ) its (10) circumferential surface, performing a single turning cycle, according method of invention.

After turning cycle, a decoding scan of encoded information (14) is performed using an optical industrial vision instrument for non-contact measurements, said instrument measures the dimensions of depths and widths of turned engravings (12), as well as the widths of spaces (13) intercalated to the same (12) and decodes meaning of conventionally associated information by means of decoding software whose instructions have been programmed in accordance with previously set information encoding model.

In another preferred but non limiting embodiment of said marking method, an encoding information (24) has been turned at 360° around (21 ) the circumferential surface of lower face (20) of said gear, as illustrated in Fig. 2.

Said turned code (24) comprises a plurality of encoded engravings (22), turned at 360° around (21 ) its surface, each of which is intercalated by an encoded space (23).

Still, in another preferred but non limiting embodiment of said marking method, an encoding information (34) has been turned at 360° around (31 ) the circumferential surface of an input shaft (30), as shown in Fig. 3.

Said turned code (34) comprises a plurality of encoded engravings (32), turned at 360° around (31 ) its surface, each of which is intercalated by an encoded space (33).

Marking method according to invention is susceptible to modifications and variations all falling within inventive concept expressed in attached claims.

Invention has been described with particular reference to attached drawings, used to improve intelligence of invention and do not constitute any limitation to scope of protection claimed.