METHOD FOR PRODUCING A BEARING PRODUCT WITH AN AUTHENTICATION CODE

Technical Field

The invention relates to a method for producing a bearing product having an authentication code, to a computer program for authenticating such a bearing product and to a portable computer device with means to execute such a computer program.

Premium manufacturers of bearing products such as roller bearings, bearing rings or other related products need to offer superior quality and offer warranties in order to meet the requirements of their customers.

At the same time, an increasing number of counterfeit products produced by illegal bearing manufacturers are detected on the market. New low-quality bearings are relabeled with false brand markings and put into imitation packaging that appears to be identical to the genuine product. Further, bearings are re-manufactured and then sold with no indication that they have been re-manufactured, and very old bearings are cleaned, polished and supplied without the buyer being informed how old the bearing really is.

It is therefore known to equip the original products with special anti-counterfeit markings, which enables at least the manufacturers to differentiate between counterfeit products and genuine products, e.g. when analyzing the reasons for a failure.

In the course of customs actions, raids or the like, a large number of bearings may need to be checked. This creates significant costs for the bearing manufacturers and may be very time consuming. Verifying whether such a bearing is counterfeit or not may be very difficult, time- consuming and costly. In the end, it is often not possible to tell with certainty whether the bearing is genuine or not. The document DE 10201 107641 1 A1 discloses a method for authenticating a bearing. A product is provided with an identifier in the form of a data-matrix-code applied using etching, laser marking or printing in a permanent way.

The authentication code is read by a mobile device and sent to a central data processing which checks whether or not an authentication code corresponds to an existing product or not. In cases of doubt, the user may be requested to provide further data of the product.

The method disclosed in DE 10201 107641 1 A1 is unable to detect counterfeits which are copies from existing products including a valid authentication code, wherein the authentication code is copied as well.

Summary of the invention The invention seeks to solve the above drawbacks of the prior art and to provide a method for manufacturing a bearing product provided with an authentication code which is difficult or impossible to imitate and/or which enables a reliable detection of counterfeits even when the counterfeits are provided with a copy of an existing authentication code.

The invention starts from a method for producing a bearing product associated with at least one product parameter. The method comprises the steps of generating at least one authentication code using at least one formula and applying the authentication code to the product.

Parameters for the formula may include the location of production, e.g. the country, factory and general number, the time of production, i.e. the year, the date, the hour, the minute and the second. It is proposed that the parameters used by the method include at least one geometrical property of the product. The geometrical properties include in particular macro- geometrical properties like bore diameter, width, number of rolling elements. Furthermore, the method may comprise the step of measuring at least one parameter describing a geometrical property of the product. The parameter describing the geometrical property is then used as at least one of the input parameters of the at least one formula. Authenticating the product is possible if the geometrical property and the formula are known.

Copying the authentication code and applying it onto a product not sharing the geometrical property with the genuine product will result in a counterfeit being easily detectable. The detection of counterfeits may be facilitated and simplified.

The bearing product may be a roller bearing, a ball bearing of any kind, a bearing part such as a bearing ring or a compound unit including a bearing. The bearing product may or may not include a bearing package and the authentication code may be applied directly onto the bearing or bearing product, i.e. to a stainless steel part thereof, or onto a package or onto a seal of the package.

Further, it is proposed that this step of generating at least one authentication code includes converting the results of the formula into a baseN number. The baseN number may be a base-6-Number of base-36-Number and enables qualifying more authentication information into a given number of digits.

Parameters for the formula may include the location of production, e.g. the country, factory and general number, the time of production, i.e. the year, the date, the hour, the minute and the second.

The geometrical property may in particular include a macro-geometrical property such as the bore diameter, outer diameter, width, number of rolling elements, etc. and/or a micro-geometrical property such as the exact outer diameter within a range of tolerance, which can be considered a random outcome of production, the exact inner diameter or the width. Further, the micro-geometrical property may include the exact diameter of the rolling elements and should preferably be a property that is not subject to wear during the bearing operation, e.g. the exact raceway shoulder height. Since these properties are random, a bearing produced by a counterfeiter will most likely have a different set of properties since it is impossible to machine e.g. an inner diameter with an accuracy as high as the measurement accuracy. As a consequence, the counterfeiter cannot copy a valid security number from an existing bearing of the same type since the micro-geometry will still be different. At least, the requirement to reproduce exactly the same geometry will eliminate the cost advan- tages of a counterfeiter such that copying the product will no longer be financially attractive.

Further, the formula may contain a random element, such that the factors of the formula change depending on the value of the random factor. For example, the first digit of the security number could be random and determine the factors used to compute the other digits, e.g. as a seed of a random number generator. Preferably, the formula contains multiple complexity levels, e.g. including multiplications with large digits or prime numbers and modulo divisions of the result such that the formula is practically impossible to reverse.

Further, it is proposed to use at least one letter printed onto the product using a method described in WO 201 1/076229 A1 as input parameter for the formula. A further potential security feature could include small dimples provided at a defined location of the bearing, wherein the position, depth or arrangement of the dimples could be used as input parameter for the formula used to generate the authentication code for the product.

The authentication code could be applied e.g. using laser marking, etching or other permanent printing techniques or the product could be provided with an RFID tag containing the security number in an encrypted format that cannot be created by the counterfeiter without knowing an encryption key and which cannot be read without knowledge of the encryption key from an existing bearing.

Further, it is proposed that the bearing is provided with a polymer cage, polymer seal or a rubber seal, wherein the RFID tag is integrated into the cage or seal during injection molding. This prevents the possibility of re-using RFID tags from existing bearings.

According to a further proposal, the box or package of the bearing is provided with a code that is linked with the security number of the bearing as described above and to the geometrical properties. This code could be provided as a further input parameter for the formula. The provision of such an additional code on the package makes it impossible to counterfeit a properly packaged bearing. The code could be directly printed onto the box, or a sticker could be put on the box or used as a seal for the box.

In a preferred embodiment of the invention, it is proposed to further provide the bearing with at least one molded polymer part, wherein the authentication code is applied on means integrally molded with the polymer part. This would make it impossible or very difficult to re-use this means, in particular an RFID tag, from existing bearings. The polymer part should be a part constitutive for the function of a bearing which is difficult to remove or to exchange, preferably, the polymer part is a cage for guiding rolling elements of the bearing. A further aspect of the invention relates to a computer program for authenticating the bearing product produced as described above. The computer product could be configured to read an authentication code and a measured parameter describing the geometrical property from an input interface. The input interface could be a user interface wherein the user may input the required data manually or could be formed as a camera or scanner or the like, wherein the geometrical properties could be determined automatically or semi-automatically using suitable image processing algorithms.

The computer program then internally generates the authentication code using the at least one formula and the parameters input via the input interface and compares the thus generated authentication code with the authentication code read from the interface. If the authentication codes are identical, the product is a genuine product and the product is a counterfeit if this is not the case. Finally, the result of the comparison is outputted as authentication result information. According to a further aspect of the invention, the step of generating the authentication code includes sending the measured parameter describing the geometrical property to a secure server and receiving in response the authentication code and/or other parameters such as random numbers or decryption keys for use in the formula from the security server.

The above description of the invention as well as the appended claims, figures and the following description of preferred embodiments show multiple characterizing features of the invention in specific combinations. The skilled person will easily be able to consider further combinations or sub-combinations of these features in order to adapt the invention as defined in the claims to his or her specific needs.

Brief Description of the Drawings

Fig. 1 illustrates a bearing product provided with a security code applied to one of the bearing rings according to a first embodiment of the invention.

Fig. 2 illustrates a bearing product provided with a security code stored in an RFID tag integrally molded with a polymer cage of the bearing.

Fig. 3 illustrates a method for providing a bearing with an authentication code according to the invention.

Fig. 4 illustrates a flow diagram of a computer program for authenticating a product according to the invention.

Fig. 5 illustrates a computer system for authenticating bearings according to the invention. Detailed Description of the Embodiments

Fig. 1 illustrates a bearing including an outer ring 12, an inner ring 10, a plurality of rolling elements 14 arranged in between and a cage 16.

The outer ring 12 is provided with an engraved or laser-printed authentication code 18 in a base36 format (digits from 0-9 and capital letters).The inner ring 10 is provided with further engraved information numbers 20a, 20b, including a product identifier 20a describing the bearing type and a further code 20b describing the production factory and production time.

Fig. 2 is a further embodiment of the invention, wherein an RFID tag 22 is integrally molded with the cage 16 of the bearing, which is formed as a polymer part in this case. The authentication code 18 is stored in an encrypted form on the RFID tag 22. This makes it very difficult or impossible to counterfeit a bearing even if the formula is known, as long as the secret encryption key to program and read the RFID tag 22 is not disclosed.

In both embodiments, the authentication code 18 is applied in a separate production step using a dedicated machine employing a technology which may be different from the technology employed for writing the further engraved information numbers 20a, 20b on the inner ring 10.

Further embodiments include such embodiments where the authentication code 18 is printed onto a package box (not illustrated) of the bearing or onto a seal of this box or where the polymer part into which the storage means, such as the RFID tag, 22 is integrated, is a rubber seal of the bearing.

The authentication code 18 may comprise multiple portions applied to different parts of the product using different technologies. The method for generating the authentication code 18 is illustrated very schematically in Fig. 3.

In Step S1 , various micro-geometrical properties and/or macro-geometrical properties are measured. In one embodiment, these properties include, but are not limited to:

• The exact bore diameter, outer diameter or width (e.g. 25.003 respectively the deviation from the nominal value: +3)

• The exact diameter of the rolling elements 14 (chosen during production to achieve required clearance)

• a property that is not subject to wear during bearing operation, e.g. the exact raceway shoulder height.

Further, parameters representative of a machining texture of machined surfaces of the bearing may be measured in Step S1 .

Preferably, this step S1 is executed in an at least semi-automated, preferably fully automated way using microscopes or laser measurement techniques and suitable image processing algorithms.

The parameters obtained in step S1 describing geometrical properties of the bearing in a wide sense could be used as input parameters for step S2.

The actual authentication code 18 is then generated in Step S2 using a formula, which is preferably difficult to invert based on an analysis of the measurable parameters measured in Step 1 alone.

Step S2 of generating the at least one authentication code 18 includes converting the result of the formula into the base36 number which will be applied to for example the outer ring 12 or encoded into the RFID tag 22. The step of generating the at least one authentication code 18 includes an encrypting step, wherein a quantity at least depending on at least one of the parameters determined in step 2 is encrypted using a predetermined encryption key.

The formula employed in step S2 maps the parameter space of the parameters measured in step S1 onto a dilute subset of the natural numbers repre- sentable as the base36 numbers with the given number K of digits used for the authentication code 18, wherein "dilute" may mean e.g. that only one randomly generated base36 number with K digits per 100.000 is compatible with a specific set of input parameters.

In step S3, the thus generated authentication code 18 is finally applied to the product using any of the technologies outlined above.

Fig. 4 schematically illustrates a flow diagram for a computer program for authenticating a bearing product produced as described above.

A computer provided with the program is configured to read in step C1 the authentication code 18 and a set of measured parameters corresponding to the parameters measured in step S1 of the production method from an input interface such as a keyboard, camera or communication interface.

In step C2, the authentication code 18 is generated based on the measured parameters using the same formula as the one used in step S2 above, wherein the parameters read in step S1 are used as input parameters.

In step C3, the thus generated authentication code 18 is compared with the authentication code 18 read from the interface.

In step C4, the authentication result information depending on the result of the comparison is output to a communication inter face and/or to a display. Further, the parameters of the authentication procedure, i.e. the parameters and the authentication code 18 received in step C1 and the result of the authentication, are stored in a database. The database may be used to make statistics on counterfeits detected for the given product and/or for given 5 regions in the world, in order to monitor trends or activities helping the anti- counterfeiting. If a record for a given authentication code 18 exists in the database when an inquiry with the same authentication code 18 is received, this means that either the same bearing was examined twice or that one of the two bearings carrying the same unique authentication code 18 is a i o counterfeit. A corresponding warning message may then be issued.

Fig. 5 illustrates a system setup implementing an authentication method according to the invention. The setup includes a microscope 24 for measuring the parameters, a mobile device 26, such as a notebook computer or smartphone running a suitable 15 application software, and a remote security server 28.

In a first version of the system, the computer program as described above with reference to Fig. 4 is implemented in the security server 28. The computer program is modified such that the step of generating the one authentication code 18 includes 20 receiving the measured parameter describing the geometrical property by the

security server 28 from the mobile device 26 and sending in response the authentication code 18 and/or other parameters for use in the formula from the security server 28.

25 The receipt of the data packet with the measured parameters and the authentication code 18 in the security server 28 corresponds to step C1 above, and the sending of the response corresponds to step C4.

In a further version of the system, the computer program is implemented in the 30 mobile device 26, wherein the step of generating the authentication code 18

includes sending the measured parameters and/or other product identifies such as the information numbers 20a, 20b on the inner ring 10 in Figs. 1 and 2 to a security server 28 and receiving in response the authentication code 18 and/or other parameters for use in the formula from the security server 28. The parameters may include encryption keys or other secret parameters needed in the formula.

The invention makes it impossible for a counterfeiter not knowing the formula used by the manufacturer to generate a correct authentication code 18 for the counterfeit bearing.

Using individual and non-reproducible properties of the bearing such as micro- geometrical parameters or parameters relating to the texture of a grinding pattern makes it very difficult if not impossible to reverse engineer the formula unless a very large number (millions) of bearings are analyzed.

Since these properties are random, a bearing produced by a counterfeiter will most likely have a different set of properties, since it is impossible to machine e.g. an inner diameter with an accuracy as high as the measurement accuracy. Therefore, the counterfeiter cannot even copy a valid security number from an existing bearing of the same type, since the micro-geometry will still be different.

The idea of using random production properties as "fingerprints" for the products, makes it impossible to copy the (correct) PIN from an existing bearing and apply it on a counterfeit bearing.

For some of the other products that are intended to be protected in this way, these properties might not be available, e.g. for grease or maintenance products.