WO2005051640A1 - Tire manufacturing method for improving the uniformity of a tire - Google Patents
Tire manufacturing method for improving the uniformity of a tire Download PDFInfo
- Publication number
- WO2005051640A1 WO2005051640A1 PCT/US2004/039021 US2004039021W WO2005051640A1 WO 2005051640 A1 WO2005051640 A1 WO 2005051640A1 US 2004039021 W US2004039021 W US 2004039021W WO 2005051640 A1 WO2005051640 A1 WO 2005051640A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- tire
- vector
- uniformity
- improving
- cure
- Prior art date
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 38
- 239000013598 vector Substances 0.000 claims abstract description 274
- 238000000034 method Methods 0.000 claims abstract description 127
- 230000000694 effects Effects 0.000 claims abstract description 104
- 238000005259 measurement Methods 0.000 claims abstract description 53
- 238000005457 optimization Methods 0.000 claims description 27
- 238000012546 transfer Methods 0.000 claims description 13
- 239000011159 matrix material Substances 0.000 claims description 5
- 238000003384 imaging method Methods 0.000 claims description 3
- 238000004073 vulcanization Methods 0.000 abstract description 13
- 230000008569 process Effects 0.000 description 16
- 239000002131 composite material Substances 0.000 description 13
- 230000015572 biosynthetic process Effects 0.000 description 9
- 230000006872 improvement Effects 0.000 description 5
- 230000004044 response Effects 0.000 description 4
- 101000812663 Homo sapiens Endoplasmin Proteins 0.000 description 3
- 101000689394 Homo sapiens Phospholipid scramblase 4 Proteins 0.000 description 3
- 101000796673 Homo sapiens Transformation/transcription domain-associated protein Proteins 0.000 description 3
- 101001067395 Mus musculus Phospholipid scramblase 1 Proteins 0.000 description 3
- 102100024494 Phospholipid scramblase 4 Human genes 0.000 description 3
- 238000012937 correction Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000000611 regression analysis Methods 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 230000002730 additional effect Effects 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000002372 labelling Methods 0.000 description 1
- 238000012417 linear regression Methods 0.000 description 1
- 238000012067 mathematical method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000002945 steepest descent method Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M1/00—Testing static or dynamic balance of machines or structures
- G01M1/30—Compensating imbalance
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D30/00—Producing pneumatic or solid tyres or parts thereof
- B29D30/06—Pneumatic tyres or parts thereof (e.g. produced by casting, moulding, compression moulding, injection moulding, centrifugal casting)
- B29D30/0601—Vulcanising tyres; Vulcanising presses for tyres
- B29D30/0662—Accessories, details or auxiliary operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D30/00—Producing pneumatic or solid tyres or parts thereof
- B29D30/06—Pneumatic tyres or parts thereof (e.g. produced by casting, moulding, compression moulding, injection moulding, centrifugal casting)
- B29D30/0601—Vulcanising tyres; Vulcanising presses for tyres
- B29D30/0662—Accessories, details or auxiliary operations
- B29D2030/0665—Measuring, calculating and correcting tyre uniformity before vulcanization
Definitions
- the present invention relates to a manufacturing method for tires, more specifically a method for improving the uniformity of a tire by reducing the after cure radial force variation.
- the after cure radial force variation RSV
- the radial force variation in a cured tire exceeds acceptable limits, the result may be unwanted vibrations affecting the ride and handling of the vehicle. For these reasons, tire manufacturers strive to minimize the level of radial force variation in the tires delivered to their customers.
- a well-known and commonly practiced method to improve the after cure RFV is to grind the tread surface of the tire in the zones corresponding to excess radial force. This method is effective, but has the drawback of creating an undesirable surface appearance and of removing wearable tread rubber from the product. In addition, this method requires an extra manufacturing step and uses expensive equipment.
- the after cure RFV may be improved by the method described in US Patent 5,365,781 where the sidewalls of the cured tire are physically deformed in a controlled manner in response to a measured uniformity characteristic. This method eliminates the undesirable removal of tread rubber, but still requires an extra manufacturing step and high-cost equipment.
- An alternative to after cure correction of RFV is to treat the sources of RFV in the tire before cure. For example, it is well known in the tire industry to stagger the starting points of the various tire products during the assembly process, followed by observing the effect on after cure RFV. These data are then used to specify an optimum arrangement of product start points for each of the tire building steps according to the configuration that best minimizes after cure RFV.
- Another approach is disclosed in United States Patent 5,882,452 where the before cure radial runout (RRO) of the tire is measured, followed by a process of clamping and reshaping the uncured tire to a more circular form.
- Still another approach to a manufacturing method for improved uniformity involves a method where the factors relating to tire building and tire curing that contribute to after cure RRO or RFV are offset relative to a measured before cure RRO.
- An example of a typical method is given in Japanese Patent Application JP-1-145135.
- a sample group of tires usually four, are placed in a given curing mold with each tire rotated by an equal angular increment. The angular increment is measured between a reference location on the tire, such as a product joint, relative to a fixed location on the curing mold.
- the tires are vulcanized and their composite RFV waveforms recorded.
- composite waveform means the raw waveform as recorded from the measuring device.
- the waveforms are then averaged by superposition of each of the recorded waveforms upon the others.
- Superposition is a point by point averaging of the recorded waveforms accomplished by overlaying the measured composite waveform from each tire. The effects of the vulcanization are assumed to cancel, leaving only a "formation" factor related to the building of the tire.
- another set of sample tires is vulcanized in a curing mold and their respective RFV waveforms are obtained.
- the respective waveforms are again averaged by superposition, this time with the staring points of the waveforms offset by the respective angular increments for each tire.
- the factors contributing to the formation factor can vary considerably during a manufacturing run.
- these methods contain contradictory assumptions.
- the methodology used to determine the vulcanization factor relies on an assumption that the step of rotation of the tires in the curing mold cancels the tire building (or formation) effects. This assumption is valid only when the contribution of before cure RRO is consistent from one tire to the next tire, without random contributions. If this assumption is true, then the subsequent method for determination of the formation factor will produce a trivial result.
- the present invention provides a tire manufacturing method that can effectively reduce the after cure radial force variation (RFV) of each tire produced.
- the method of the present invention operates to optimize each harmonic of RFV.
- a composite RFV signal such as those described above, is a scalar quantity that is the variation of the tire's radial force at each angular position around the tire from the average radial force corresponding to the vertical load applied to the tire.
- each harmonic of RFV can be expressed in polar coordinates as an after cure RFV vector. This vector has a magnitude equal to the peak-to-peak magnitude of the force variation of the respective harmonic and an azimuth equal to the angular difference between the measuring reference point and the point of maximum RFV.
- the method of the present invention provides a significant improvement over previous methods by employing a vectorial representation of the several factors that contribute to the measured after cure RFV for a tire produced by a given process.
- the after cure RFV vector is modeled as a vector sum of each of the vectors representing RFV contributions arising from the tire building steps - the "tire room effect vector” and a vector representing RFV contributions arising from the vulcanization and uniformity measurement steps - the "curing room effect vector.”
- both the tire room and curing room vectors can be further decomposed into sub-vectors representing each RFV contribution for which a measurable indicator is available.
- the method obtains such measurements as the before cure radial runout (RRO) at one or more stages of the building sequence, measurements of loading angles on the tire building equipment, and measurements made during vulcanization process.
- RRO radial runout
- the tires are mounted on a uniformity measurement machine and the measured after cure RFV harmonic components are obtained.
- none of the coefficients for the magnitude and azimuth of the sub-vector components is known.
- the present invention further improves on previously described methods since it does not rely on manipulation of the measured, composite RFV waveforms to estimate the tire room and curing room effects and does not rely on any of the previously described assumptions.
- the present invention uses the aforementioned measured data as input to a single analysis step. Thus, the coefficients of all the sub- vectors are simultaneously determined. Once these coefficients are known, the tire room effect vector and curing room effect vector are easily calculated. Thereafter, as the individual tires are manufactured, the before cure RRO and other manufacturing data are measured and recorded at one or more steps during the manufacture of the tires. These data are input to the vector model and the magnitude and azimuth of the tire room effect vector are calculated.
- a method for improving the uniformity of a tire comprises the steps of:
- the method of the invention just described further improves on previous methods in its treatment of the factors relating before cure RRO to after cure RFV. It has been found that RRO variations on the before cure tire do not always produce an after cure RFV contribution that is a scalar multiple of the RRO vector either in magnitude or azimuth. Thus, a scalar representation that relies on a simple stiffness factor can lead to erroneous result.
- the contribution of green tire RRO to after cure RFV may at least include effects owing to the radial RRO of the green tire carcass, the RRO of the tread and belt assembly, and a certain level of RRO owing to manufacturing tooling effects not accounted for by any of the green tire RRO effects.
- the contribution of the green RRO to after cure RFV is modeled as the vector product of a gain vector GC and a green tire RRO vector GR1.
- the gain vector correctly models the transformation from before cure RRO to after cure RFV. At least one pair of vector coefficients corresponds to the gain vector.
- a first part of the green tire vector can be estimated by combining the first harmonic RRO vector of the green carcass, GR1C, with a carcass gain vector, GNC.
- the vector product of GNC and GR1C is known as the carcass effect vector. This effect may vary from tire to tire.
- a second part of the green tire vector may be modeled by combining the first harmonic of the RRO vector of the green tread and belt assembly, GRIT, with a tread and belt assembly gain vector, GNT.
- the vector product of GNT and GRIT is known as the tread and belt assembly effect vector. This effect may also vary from tire to tire.
- a third part of the green tire vector is due to "tooling" effects not captured by GR1C or GRIT.
- These tooling vectors are constant vectors and whose magnitude is not expected to vary from tire to tire.
- Examples of the tooling effects are vector components related to tire building apparatus such as the First Stage Building drum vector, the Second Stage Building drum vector, Tread and Belt Assembly Building drum vector, and the Transfer Ring vector.
- the Intercept vector models any other constant effect not described by the any of the previous vectors.
- the tooling effects allow an improvement to the accuracy of the model.
- the measured RRO is the sum of the actual green tire RRO and the RRO of the measuring device upon which the tire is currently mounted, be it building drum or a measurement apparatus.
- the step of determining a set of vector coefficients further comprises the sub-step of recording a loading angle of a tire carcass on any or a combination of the first stage tire building drum, second stage tire building drum, or transfer ring.
- the step of estimating the after cure uniformity of an individual tire further comprises the sub-step of recording a loading angle of a carcass of an individual tire on the same tooling.
- the tooling effects may be manipulated during the tire building steps to minimize further the after cure RFV. This is accomplished by altering the magnitude of the tire room effect vector according to an optimization criterion. This method comprises the steps of:
- the after cure RFV can be further improved if the manufacturing process permits the loading of the tire in a mold at a predetermined azimuth angle.
- the optimization criterion is that the magnitude of a tire room effect vector is substantially equal to the magnitude of a curing room effect vector.
- the green tire is then aligned at the predetermined curing room azimuth angle, loaded in a curing mold, and cured.
- the optimization criterion is to minimize the magnitude of the tire room vector alone.
- the RRO is measured during the building of the tire for the RRO of the completed green carcass, the RRO of the tread and belt assembly, and for the finished green tire. At each intermediate step the then measured RRO may be offset by an azimuth matching with the tooling effects.
- the method of the invention has an additional advantage owing to its simultaneous determination of the sub-vectors. Unlike previous methods, the method of the invention does not require any precise angular increments of the loading positions to determine the sub-vectors. This opens the possibility to update continuously the sub-vector coefficients using the measured data obtained during the production runs. Thus, the method will take into account production variables that arise during a high volume production run.
- Fig. 1 is a schematic representation of a tire manufacturing process equipped to practice the method of the invention.
- Fig. 2A - Fig 2C depict schematic representations of a uniformity measurement of the radial force variation of a tire showing the original composite waveform as well as several harmonic components.
- Fig. 3 is a vector polar plot of the method of the invention showing the contributions of the tire room and curing room vectors to the after cure radial force variation of a tire.
- Fig. 4 is a vector polar plot of the method of the invention demonstrating the optimization of cured tire uniformity.
- Fig. 5 is a vector polar plot of the method of the invention showing the contribution of green tire radial runout to the tire room effect vector.
- Fig. 6 is a vector polar plot of the method of the invention showing the effect on the green tire vector of the measurement drum used to measure green radial runout.
- Fig. 7 is a vector polar plot of the method of the invention adding the effect of the after cure uniformity measurement machine.
- Fig. 8 is a vector polar plot of an expanded method of the invention showing the effect on the green tire vector of additional components effects due to green tire carcass, the tread and belt assembly, and for the tooling effects of First Stage drum, the Tread and Belt Assembly drum, and the Transfer Ring.
- Fig. 9 is a vector polar plot of an expanded method of the invention demonstrating the optimization of cured tire uniformity.
- a certain radial force reacting on the flat surface that is a function of the design of the tire can be measured by a variety of known means. This radial force is, on average, equal to the applied load on the tire. However, as the tire rolls, that radial force will vary slightly due to variations in the internal tire geometry that lead to variations in the local radial stiffness of the tire. These variations may be caused on the green tire by localized conditions such as product joints used in the manufacture of the green tire or inaccurate placement of certain products. The process of curing the tire may introduce additional factors due to the curing presses or slippage of products during curing.
- FIG. 1 shows a simplified depiction of the tire manufacturing process.
- a tire carcass 10 is formed on a building drum 15. In a unistage manufacturing process, the carcass 10 remains on the drum 15. In a two-stage process, the carcass 10 would be removed from the drum 15 and moved to a second stage finishing drum (not shown). In either case, the carcass 10 is inflated to receive a finished tread band 20 to produce the finished green tire 30.
- the RRO of the green tire 30 is measured by a measurement system 70 using a barcode 35 as a reference point. The RRO waveform is stored, here in a computer 80.
- the green tire 30 is moved to the curing room where the orientation angle of the tire CAV_REF is recorded. The tire is then loaded into a curing cavity 40 and cured.
- the cured tire 30' is moved to a uniformity measurement machine 50 for measurement and recording of the tire RFV.
- Figure 2 A shows a schematic of the measured RFV for a cured tire 30'.
- the abscissa represents the circumference of the tire and the ordinate the radial force variations.
- Figure 2A is the as- measured signal and is referred to as a composite waveform.
- the composite waveform may comprise an infinite series of harmonics.
- the individual harmonics may be obtained by applying Fourier decomposition to the composite signal.
- Figures 2B and 2C depict the resulting first and second harmonics, respectively, extracted form the composite signal.
- the magnitude of the first harmonic of radial force VRM1 is defined as the difference between the maximum and minimum force.
- the phase angle or azimuth of the first harmonic VRA1 is defined as the angular offset between the reference location for the measurement and the location of maximum radial force.
- Cartesian coordinates in Fig. 2B can be equally shown as a vector in a polar coordinate scheme.
- Such a vector polar plot is shown in Fig. 2C immediately to the right of the sine wave plot.
- the RFV vector of the first harmonic VRHl has a length equal to VRMl and is rotated to an angle equal to the azimuth VRAl.
- the second harmonic vector VRH2 shown in Fig. 2C that has a force magnitude VRM2 and an azimuth VRA2.
- the corresponding polar plot for the H2 vector resembles the HI vector, except that the angular coordinate is now two times the azimuth angle.
- the particular example is 1 confined to the optimization of the first harmonic HI.
- the method to optimize a different harmonic such as H2, H3, etc.
- the following example describes the optimization of radial force variation, whereas it is within the scope of the invention to apply the method to the correction of other uniformity characteristics such as cured tire radial runout or lateral force variation.
- the method may be used to optimize the harmonics of any measurable uniformity characteristic with suitable modifications to the vector equations described below.
- Figure 3 is a vector polar plot showing the two major contributions to first harmonic of the after cure radial force variation, the tire room effects vector TR1, and the curing room effects vector CR1 when no optimization has been applied.
- the cured tire result VRHl is the vector sum of these two components.
- a unique attribute of the invention is the ability to optimize the after cure uniformity by manipulation of these two component vectors. The ability to treat these effects in vector space is possible only when each harmonic has been extracted.
- FIG. 4 now shows a schematic of the optimization step.
- the green tire 30 has been physically rotated by a pre-determined angle CAV_REF so that its tire room effect vector (TR1') now directly opposes the curing room effect vector CR1, the latter being fixed if there are no changes to the setup or state of the curing equipment 40. It is readily apparent that this optimization greatly reduces the after cure result VRHl'.
- Both the tire room and curing room component vectors are the result of many individual factors, or sub-vectors.
- Each sub-vector is a contribution to the cured tire RFV and these vectors have units that correspond to radial force variation, i.e. kilograms.
- Figure 5 demonstrates one such sub-vector, the effect of green tire radial runout indicated as GR1*GN.
- This sub-vector represents the vector product of the green RRO (mm) and a gain vector that models the localized radial stiffness (Kg/mm).
- the gain vector is not a simple scalar factor as used in previous methods, but is a true vector that accounts for circumferential radial stiffness variation around the green tire 30.
- the remaining, unidentified factors are consolidated in the Intercept vector II. If all factors were known, then the Intercept vector II would not exist. Throughout this disclosure, the Intercept vector II accounts for the unidentified effects.
- Figure 6 further declinates the tire room sub-vectors showing a first representation of the tooling effects.
- the measurement of green tire RRO is preferably at the completion of tire building and before the green tire is removed from the building drum 15.
- the measurement drum is the tire building drum 15, the single drum of a unistage machine, or the finishing drum of a two-stage machine.
- the green tire RRO measurement may also be performed offline in a dedicated measurement apparatus. In either case, the radial runout of the measurement drum can introduce a false contribution to the Green RRO vector.
- the result is the sum of true tire runout and the runout of the drum used for measurement of RRO.
- the method of the invention includes a sub-vector T2 due to the measurement drum to account for this false RRO effect.
- the sub-vector advantage can also be use to improve the curing room effects.
- Figure 7 depicts an additional sub- vector UM1 to account for this effect showing the difference between the measured radial force vector VRHl and the true radial force vector TVRHl.
- This sub-vector imparts a small, but significant correction to the rotation angle CAV_REF shown in Fig. 4 for optimizing VRHl. Studies have shown that the inclusion of the UM1 sub-vector can improve the magnitude VRMl of the true radial force vector VRHl by about 0.5 to 1.0 Kg.
- the first step in implementation of the method is to gather data to build the modeling equation.
- the Green RRO and VRHl vectors are measured quantities.
- the challenge is to estimate the gain vector GN, the building drum vector T2, the intercept vector II, and the curing room effect vector CR1. This is accomplished by vector rotation and regression analysis.
- a reference point on the tire such as a barcode applied to the carcass or a product joint that will be accessible through then entire process is identified.
- the invention contains an improvement to account for the radial runout of the measurement drum itself. This effect may be significant when the tire building drum 15 is used as the measurement drum.
- the loading angle FBD_REF of the tire carcass on the measurement drum is recorded.
- the loading angle is measured as the carcass 10 is loaded on either the first stage of a unistage or a second stage of a two-stage machine. It is advantageous to ensure a wide variation of the loading angle FBD_REF within a given sample of tires to ensure accurate estimation of the effect of the measurement drum runout on the vector coefficients.
- the RRO of the finished, green tire 30 is measured by a measurement device 70 while the tire is mounted on the finishing stage building drum 15.
- the finished, green tire may be moved to separate measurement apparatus and the RRO measurement made there.
- This RRO measurement is repeated for multiple tires to randomize the effects that are not modeled.
- devices 70 to obtain the RRO measurement such as a non-contact system using a vision system or a laser. It has been found that systems for measurement of radial runout that are based on tangential imaging are preferred to those using radial imaging.
- the RRO data thus acquired are recorded in a computer 80.
- each green tire 30 is transferred to the curing room and the identification of the curing cavity 40 where each green tire is to be cured or vulcanized is recorded as well as the orientation azimuth CAV_REF at which each green tire is loaded into the curing cavity. It is advantageous to ensure a wide variation of the orientation azimuth within a given sample of tires to ensure accurate estimation of the curing cavity effect on the vector coefficients.
- the cured tire 30' is moved to the uniformity measurement machine 50 to acquire the radial force variation RFV for each tire.
- the RFV data thus acquired are also recorded in a computer 80.
- the model is extended to include a uniformity machine sub-vector UM1, then similar steps to those outlined above for the building drum vector are applied at the uniformity measurement machine.
- a loading angle for the cured tire on the uniformity measurement machine UM_REF similar to the second stage carcass loading angle FBD_REF, is recorded and stored in the computer 80 with the associated RFV data for a sample of tires.
- the sub-vector UM1 can then be added to the model using the same vector analysis procedure as described herein to obtain the building drum sub-vector T2.
- the model will contain an additional pair of coefficients to obtain a magnitude UMMl and an azimuth UMAl of the sub-vector UMl to improve the estimation of after cure RFV.
- the harmonic data are extracted from the RRO and RFV waveforms.
- the first harmonic data of the green radial runout GR1 (magnitude FRM1 and azimuth FRA1) and radial force variation VRHl (magnitude VRMl and azimuth VRAl), respectively are extracted and stored.
- Each vector in equation (2) above has a magnitude and an azimuth as previously defined.
- each vector or sub-vector has an x-component and a y-component as shown in the example below:
- VRHl ⁇ (VRMl)*COS(VRAl)
- VRH1 Y (VRM1)*SLN(VRA1) (4) where the parentheses indicate the scalar values of magnitude and azimuth of the quantity within.
- the dependent vector (VRH1 X , VRH1 Y ) is sum of the vectors in the equations below.
- VRHl ⁇ GN-FRM1-C0S( ⁇ +FRA1) + (9) CM1-C0S(CA1+CAV_REF) + TM1-C0S(TA1+FBDJREF) + IMl-COS(IAl)
- VRH1 Y GN FRM1-SIN( ⁇ +FRA1) + CM1-SIN(CA1+CAV_REF) + (10) TM1-SIN(TA1+FBD_REF) + IMl-STN(IAl)
- Y GN- COS( ⁇ ) • FRMI-S ⁇ N(FRAI) + GN- S ⁇ N( ⁇ ) • FRMl-COS(FRAl) + CMl-COS(CAl) • S ⁇ N(CAV_ EF) + CMl-SIN(CAl) • COS(CAV_REF) + TMl-COS(TAl) • S ⁇ N(FBD_REF) + TMl-SIN(TAl) • COS(FBD_REF) + .
- the equation (15) above provides a modeling equation by which the VRHl vector for an individual tire may be estimated.
- This basic formulation can also be modified to include other process elements and to account for different production organization schemes.
- These coefficient vectors may be obtained by various known mathematical methods to solve the matrix equation above.
- the method is more easily implemented if the coefficients are determined simultaneously by a least-squares regression estimate. All coefficients for all building drums and cavities may be solved for in a single regression step. Finally, the vector coefficients are stored in a database for future use.
- the coefficients have a physical significance as follows: (a, b) is the gain vector GN in units of kgf/mm, (c, d) is the curing room effect vector CR1 in units of kgf, (e, f) is the building drum vector T2 in units of kgf, and (Il x , II ⁇ ) is the Intercept vector II in units of kgf.
- the equations listed above are for one curing cavity and one building drum.
- the curing cavity and building drum are nested factors meaning that although the actual process contains many building drums and many cavities, each tire will see only one of each.
- the complete equation may include a vector for each building drum and each curing cavity as shown below.
- Expanding the model first requires the creation of the following matrices V ⁇ , Cj j , and X tj , where the subscript "i” denotes mold i and the where the subscript "j” denotes building machine drum j, the subscript pair “ij” denotes a tire manufactured on building drum “j” and cured in curing cavity "i”: FRM ⁇ X -FRMl y CAV_REF X -CAV _ REF FBD_REF X FBD _ REF 1 0
- the final step is to apply the model to optimize the RFV of individual tires as they are manufactured according to the illustration shown in Fig. 4.
- Each tire building drum carriers an identification "j" and each curing cavity an identification "i.”
- Each tire carries a unique identification device, such as a barcode. These identification tags allow the information recorded for an individual tire to be retrieved at a later step.
- the green RRO is measured and its harmonic magnitude FRMl and azimuth FRAl are recorded along with the loading angle FBD_REF of the tire on the building or measurement drum.
- the curing cavity in which it will be cured will be predetermined and the curing room effect vector information for that cavity may be retrieved from the database.
- a reading device scans the unique barcode to identify the tire, to facilitate polling the database to find the measured and recorded tire information: FRMl and FRAl, the building drum identification, and the loading angle FBD_REF.
- FRMl and FRAl the measured and recorded tire information
- FBD_REF the loading angle
- TR1 Y a • GR1 Y + b • GR1 X + e • FBD_REF ⁇ + f ⁇ FBD_REF X + Il ⁇ (20)
- the azimuth TRA1 of the tire room effect vector TR1 is the inverse tangent of the quantity (TR1 Y /TR1 X ), and the azimuth CA1 of the curing room effect vector CA1 is the inverse tangent of the quantity (d/c).
- the green tire 30 is rotated so that its orientation angle CAV_REF relative to the curing cavity 40 is such that azimuth TRA1 of the predicted tire room effect vector is opposed to the azimuth CA1 of the curing room effect vector. This operation may be expressed in the equation below:
- the green tire 30 is then loaded into the curing cavity 40 at the orientation angle CAV_REF that minimizes RFV in the cured tire 30'.
- all steps of the method, determining the vector coefficients, estimating the after cure RFV, and optimizing the after cure uniformity, are carried out using the specific identifiers of the process equipment. In this manner, a tire produced on any building machine can be cured in a curing cavity with an optimized level of RFV.
- the tire In the case where the tire does not have a unique identifying barcode, it is not possible to perform the entire optimization process at the curing room. In this case, the tire must be marked to indicate the azimuth TRAl of the tire room effect vector TR1 while the tire is at the tire building machine.
- the azimuth of the tire room effect vector of the green tire is calculated using the vector- regression method, and a mark is placed on the tire corresponding to the azimuth angle TRAl.
- the curing cavity 40 has been previously marked at an azimuth (CA1-180) diametrically opposed- to the curing room effect vector CA1.
- the pre-applied mark on the tire 30 indicating the azimuth TRAl is aligned with the pre-applied mark on the curing cavity 40.
- the tire room effect vector TR1 and the curing room effect vector oppose each other and the after cure VRHl will be optimized.
- Another advantageous and unique feature of the invention is the ability to update the predictive coefficients vectors (a, b), (c, d), (e, f), and (I x , I ⁇ ) with the data measured from each individual tire to account for the constant variations associated with a complex manufacturing process. Because the green RRO and cured RFV of individual tires are continuously measured, the model may be updated at periodic intervals with these new production data to adjust the predictive equations for changes in the process. These updates may be appended to the existing data or used to calculate a new, independent set of predictive coefficient vectors that may replace the original data.
- Figure 8 is a vector polar plot of an expanded method of the invention showing the effect on the green tire vector GR1*GN of additional components effects due to green tire carcass, the tread and belt assembly, and for the tooling effects of first stage drum, the tread and belt assembly drum, and the transfer ring. This may be accomplished through suitable modifications of the foregoing system of vector equations.
- the green tire effect vector GR1*GN is now capable of being described by the component sub-vectors corresponding a set of tire component sub-assemblies and a set of tooling effects.
- TR1 GR1C*GNC GR1T*GNT + TI + T2 + T3 + T4 + II (23) and the estimated after cure uniformity remains as in equation (1) :
- VRHl TR1 + CR1 (24)
- TR1 is now represented by the new equation (23).
- One skilled in the art may follow the same methodology as described previously in the vector equations (4) through (15) to expand the set of predictive equations to correspond to the expanded tire room vector equation (23). The result below shows the x and y components of RFV:
- a multiple linear regression routine is used to estimate simultaneously coefficients vectors (a, b), (c, d),
- the vector (a, b) is the carcass gain vector GC and will be in units of kgf/mm.
- the vector (c, d) is the tread and belt assembly gain vector GT and will be in units of kgf/mm.
- the vector (h, j) is the first stage building drum tooling vector TI and is in units of kgf.
- the vector (k, m) is the second stage building drum tooling vector T2 and is in units of kgf.
- the vector (n, p) is the tread and belt assembly building drum tooling vector T3 and is in units of kgf.
- the vector (q, r) is the transfer ring tooling vector T4 and is in units of kgf.
- the vector (s, t) is the curing room effect vector CR1 and is in units of kgf.
- the vector (Ilx, Ily) is the intercept, vector and is in units of kgf.
- the expanded model may be practiced in the following illustrative manner.
- the method is practiced as previously described, but with additional steps. For example, if the model is to include the first stage building drum sub-vector TI, then it will be necessary for the data on the sample of tires to include a recording of the carcass loading angle on the first stage drum CBD_REF. Likewise to account for the green tire carcass sub-vector GR1C and the carcass gain GNC, a measurement of the RRO of the green carcass is necessary.
- carcass means the components of the green tire minus the tread and belt assembly.
- the tread and belt assembly sub-vector GRIT and tread gain GNT can be included through measurements of the tread and belt assembly loading angle SBD_REF of these tire components on a form commonly used to build this assembly, followed by a measurement of the green RRO of the assembly on the building form.
- the transfer ring tooling effect T4 accounts for uniformity effects introduced by the apparatus use to transfer the tread and belt assembly 20 from the building form to a position to be joined with the green carcass. The tooling effect T4 is accounted for by a measurement of the loading angle in the transfer ring TSR REF.
- the model is then applied to optimize the after cure RFV of an individual tire.
- the steps described herein apply to a two-stage building process where the carcass and tread and belt assemblies are built as separate components, and then joined to complete the tire. It is within the scope of the invention to apply the method to other tire building methods. Specifically the optimization of these tire building steps will be performed using the coefficient derived in the model building step. Using the tooling effects and the measured radial runout effects, the optimal relative angles of loading of the carcass 10 and the tread and belt assembly 20 will be generated and either marked on the elements or preferably automatically rotated to the selected angles by machine control systems. At the start of tire building, the first stage building drum identification is recorded, followed by building the carcass.
- the carcass RRO measurements are made on the first stage drum and the carcass effect vector GR1C*GC is computed.
- the tooling contribution is known through the tooling vector TI.
- the carcass RRO measurements may be made on the second stage building drum, in which case the tooling vectors TI and T2 may be used.
- the tread and belt assembly steps begin with recording the building from identification, followed applying the belts and the tread band.
- the tread and belt assembly RRO is measured on the form and tread and belt assembly effect vector GR1T*GT is computed.
- the tooling contribution of the building form is known through the tooling vector T3.
- the optimization method may be applied in several variations depending on the level of sophistication of the manufacturing equipment.
- the equipment allows labeling of the tire components for identification and azimuth.
- the equipment also allows for selection of curing molds and for loading of the tire in a curing mold at an azimuth orientation determined form the model.
- the after cure RFV is reduced by building a green tire 30 having a magnitude of the tire room effect vector TR1 equal or nearly equal to the magnitude of the curing room effect vector CR1.
- Figure 9 represents this variation.
- the optimized tire room effect vector TR1 is now shown as a dotted line to demonstrate the matching of its magnitude to that of the curing room effect vector CR1.
- Figure 9 further demonstrates that the manipulation of the green tire effect vector GR1C*GN, also show by a dotted line.
- the two effects are nearly equal and opposite, and the after cure RFV is minimized.
- the errors in measurement and in the accuracy of the model are such that one would not expect to produce a tire with zero after cure RFV. If the manufacturing equipment is less sophisticated and does not permit the match loading in the curing mold, then the optimization may be used simply to minimize the tire room effect vector TR1 alone.
- the optimization method is applied similarly for both the preceding examples.
- an optimization criterion is chosen depending on the manufacturing environment.
- the intended curing mold is known and its respective curing room effect vector CR1 is known.
- the optimization criterion is the magnitude CMl of the curing room effect vector CR1.
- the optimization criterion is set to any desired level. For example, to minimize the tire room effect vector TR1, the optimization criterion is set to zero.
- the optimization method is used to determine an optimum set of loading angles on the second stage building drum FBD_REF and the transfer ring TSR_REF to produce a tire with the predete ⁇ nined value of CMl.
- the curing room azimuth angle CAVJREF is simultaneously determined for future use.
- the vector system just described forms a response surface for the estimated tire room effect vector TR1 as a function of the component sub-vectors.
- the response surface may have a single maximum or several local maxima. It has been found that the optimized solution can be efficiently determined using a well-known non-linear, steepest descent method based on commercially available code.
- the steepest descent routine is run using more than one set of starting values to increase the likelihood that the best solution is obtained.
- Other optimization methods are possible such as quadratic optimization, linear descent, or even an exhaustive search.
- the next steps are to complete the tire 30 according to the optimized loading angles.
- the tread and belt package 20 is loaded on the summit transfer ring at the predete ⁇ nined angle TSR_REF, and the carcass 10 is loaded on the second stage building drum at the predetermined angle FBD_REF.
- the carcass 10 can then be inflated and joined to the tread and belt assembly 20 to complete the green tire 30.
- the before cure RRO of finished tire can be measured to assess the robustness of the model.
- the green tire 30 is moved to the curing room and then loaded into the curing cavity 40 at the azimuth angle determined from CAV_REF that minimizes RFV in the cured tire 30'.
- Experimental results obtained during the verification of the method have shown that the present invention is able to account for a significantly higher percentage of the cure tire RFV than previous methods used in with the similar manufacturing processes.
- the optimization routine determines angles FBD REF and TSR_REF.
- the carcass 20 and tread and belt package 20 are loaded at these predetermined angles to finish the tire 30.
- the green tire 30 is moved to the curing room and then loaded into any curing cavity 40 without attention to the loading angle in the cavity 40.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Testing Of Balance (AREA)
- Tires In General (AREA)
Abstract
Description
Claims
Priority Applications (16)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020067009695A KR101229247B1 (en) | 2003-11-21 | 2004-11-19 | Method for improving the after cure uniformity of a tire |
DE602004011396T DE602004011396T2 (en) | 2003-11-21 | 2004-11-19 | TIRE MANUFACTURING METHOD FOR IMPROVING THE EQUIVALENCE OF A TIRE |
PCT/US2004/039021 WO2005051640A1 (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire |
CA2545217A CA2545217C (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire |
JP2006541566A JP4714154B2 (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method with improved tire uniformity |
MXPA06005641A MXPA06005641A (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire. |
EP04811699A EP1697115B1 (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire |
BRPI0518313-8A BRPI0518313A2 (en) | 2004-11-19 | 2005-11-16 | Method for improving the uniformity of a tire |
CN200580039589.5A CN101287589B (en) | 2004-11-19 | 2005-11-16 | Tire manufacturing method for improving the uniformity of a tire |
PCT/US2005/041560 WO2006055649A1 (en) | 2004-11-19 | 2005-11-16 | Tire manufacturing method for improving the uniformity of a tire |
JP2007543202A JP4979588B2 (en) | 2003-11-21 | 2005-11-16 | Tire manufacturing method to improve tire uniformity |
EP05823461.8A EP1824665B1 (en) | 2004-11-19 | 2005-11-16 | Tire manufacturing method for improving the uniformity of a tire |
US11/437,306 US20060231191A1 (en) | 2003-11-21 | 2006-05-19 | Tire manufacturing method for improving the uniformity of a tire |
US12/482,787 US20090260743A1 (en) | 2003-11-21 | 2009-06-11 | Tire manufacturing method for improving the uniformity of a tire |
US13/014,493 US8287675B2 (en) | 2003-11-21 | 2011-01-26 | Tire manufacturing method for improving the uniformity of a tire |
US13/527,275 US20120267031A1 (en) | 2003-11-21 | 2012-06-19 | Tire manufacturing method for improving the uniformity of a tire |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IBPCT/IB2003/006462 | 2003-11-21 | ||
PCT/IB2003/006462 WO2005051638A1 (en) | 2003-11-21 | 2003-11-21 | Tire manufacturing method for improving the uniformity of a tire |
PCT/US2004/039021 WO2005051640A1 (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2003/006462 Continuation-In-Part WO2005051638A1 (en) | 2003-11-21 | 2003-11-21 | Tire manufacturing method for improving the uniformity of a tire |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/172,060 Continuation-In-Part US20070000594A1 (en) | 2002-08-01 | 2005-06-30 | Tire manufacturing method for improving the uniformity of a tire |
US11/437,306 Continuation US20060231191A1 (en) | 2003-11-21 | 2006-05-19 | Tire manufacturing method for improving the uniformity of a tire |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005051640A1 true WO2005051640A1 (en) | 2005-06-09 |
Family
ID=40095093
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2004/039021 WO2005051640A1 (en) | 2003-11-21 | 2004-11-19 | Tire manufacturing method for improving the uniformity of a tire |
Country Status (2)
Country | Link |
---|---|
JP (1) | JP4714154B2 (en) |
WO (1) | WO2005051640A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008296552A (en) * | 2007-06-04 | 2008-12-11 | Sumitomo Rubber Ind Ltd | Manufacturing method of pneumatic tire |
EP2424717A1 (en) * | 2009-04-30 | 2012-03-07 | MICHELIN Recherche et Technique S.A. | Improvement of tire uniformity through identification of process signatures |
US9120280B2 (en) | 2009-04-30 | 2015-09-01 | Michelin Recherche Et Technique S.A. | Tire uniformity through identification of process signatures |
US9645052B2 (en) | 2011-09-16 | 2017-05-09 | Michelin Recherche Et Technique S.A. | Tire uniformity through identification of process harmonics using re-indexed partial uniformity waveforms |
CN108984833A (en) * | 2018-06-07 | 2018-12-11 | 万力轮胎股份有限公司 | A kind of tire enters mould angle analysis method and device |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0492170A1 (en) * | 1990-12-21 | 1992-07-01 | Bridgestone Corporation | Method for the vectorial assembly of green tires in a curing mold |
US6415197B1 (en) * | 1997-10-08 | 2002-07-02 | The Goodyear Tire & Rubber Company | Method of displaying characteristic parameters in a tire manufacturing cell |
US6514441B1 (en) * | 1999-05-18 | 2003-02-04 | Bridgestone Corporation | Radial tire manufacturing method |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01145135A (en) * | 1987-11-30 | 1989-06-07 | Sumitomo Rubber Ind Ltd | Manufacture of radial tire |
JP3153999B2 (en) * | 1990-11-28 | 2001-04-09 | 横浜ゴム株式会社 | Tire uniformity waveform analysis method |
US5365781A (en) * | 1992-04-03 | 1994-11-22 | Michelin Recherche Et Technique S.A. | Tire uniformity correction without grinding |
JP3362883B2 (en) * | 1992-12-21 | 2003-01-07 | 株式会社ブリヂストン | Manufacturing method of radial tire |
JP3241625B2 (en) * | 1996-06-21 | 2001-12-25 | 住友ゴム工業株式会社 | Tire manufacturing method and tire manufacturing apparatus |
DE69718217T2 (en) * | 1997-10-08 | 2003-09-04 | The Goodyear Tire & Rubber Co., Akron | METHOD FOR DISPLAYING CHARACTERISTIC PARAMETERS IN A CELL FOR TIRE PRODUCTION |
JP3788866B2 (en) * | 1998-06-04 | 2006-06-21 | 株式会社ブリヂストン | High-order component prediction method and apparatus for high-speed tire uniformity, and tire manufacturing method |
JP3507945B2 (en) * | 1999-11-17 | 2004-03-15 | 東洋ゴム工業株式会社 | High-speed tire uniformity estimation method and tire selection method |
CN100395102C (en) * | 2001-11-28 | 2008-06-18 | 株式会社普利司通 | Tire producing method and tire molding machine |
US20040020583A1 (en) * | 2002-08-01 | 2004-02-05 | Fang Zhu | Method for controlling high speed uniformity in tires |
JP4072097B2 (en) * | 2003-05-29 | 2008-04-02 | 住友ゴム工業株式会社 | Manufacturing method of high-speed FV reduction tire |
JP4462859B2 (en) * | 2003-07-30 | 2010-05-12 | 株式会社ブリヂストン | Tire molding machine and tire manufacturing method |
-
2004
- 2004-11-19 WO PCT/US2004/039021 patent/WO2005051640A1/en active IP Right Grant
- 2004-11-19 JP JP2006541566A patent/JP4714154B2/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0492170A1 (en) * | 1990-12-21 | 1992-07-01 | Bridgestone Corporation | Method for the vectorial assembly of green tires in a curing mold |
US6415197B1 (en) * | 1997-10-08 | 2002-07-02 | The Goodyear Tire & Rubber Company | Method of displaying characteristic parameters in a tire manufacturing cell |
US6514441B1 (en) * | 1999-05-18 | 2003-02-04 | Bridgestone Corporation | Radial tire manufacturing method |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008296552A (en) * | 2007-06-04 | 2008-12-11 | Sumitomo Rubber Ind Ltd | Manufacturing method of pneumatic tire |
EP2424717A1 (en) * | 2009-04-30 | 2012-03-07 | MICHELIN Recherche et Technique S.A. | Improvement of tire uniformity through identification of process signatures |
EP2424717A4 (en) * | 2009-04-30 | 2012-09-19 | Michelin Rech Tech | Improvement of tire uniformity through identification of process signatures |
US9120280B2 (en) | 2009-04-30 | 2015-09-01 | Michelin Recherche Et Technique S.A. | Tire uniformity through identification of process signatures |
US9645052B2 (en) | 2011-09-16 | 2017-05-09 | Michelin Recherche Et Technique S.A. | Tire uniformity through identification of process harmonics using re-indexed partial uniformity waveforms |
CN108984833A (en) * | 2018-06-07 | 2018-12-11 | 万力轮胎股份有限公司 | A kind of tire enters mould angle analysis method and device |
Also Published As
Publication number | Publication date |
---|---|
JP2007529336A (en) | 2007-10-25 |
JP4714154B2 (en) | 2011-06-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8287675B2 (en) | Tire manufacturing method for improving the uniformity of a tire | |
EP1824665B1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
US6856929B1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
US20060137802A1 (en) | Green tire evolution for high speed uniformity | |
US6514441B1 (en) | Radial tire manufacturing method | |
JP2008520475A5 (en) | ||
JP5097910B2 (en) | Green tire evolution for high speed uniformity | |
US20120267031A1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
CN104245292B (en) | Uniformity is improved by debunching action identification | |
US20070000594A1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
WO2005051640A1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
US20090260743A1 (en) | Tire manufacturing method for improving the uniformity of a tire | |
US20040238986A1 (en) | Producing method of high speed FV reducing tire | |
KR101838468B1 (en) | Tire uniformity improvement through improved process harmonic resolution | |
JP2005186448A (en) | Method for determining connection position of tire constituting member, apparatus using method, computer program of apparatus, and storage medium storing program | |
JP2020052019A (en) | Method for estimating high-rate uniformity of tire |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200480034117.6 Country of ref document: CN |
|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2545217 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: PA/a/2006/005641 Country of ref document: MX Ref document number: 1020067009695 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2006541566 Country of ref document: JP Ref document number: 11437306 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2004811699 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 2004811699 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 11437306 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 1020067009695 Country of ref document: KR |
|
WWG | Wipo information: grant in national office |
Ref document number: 2004811699 Country of ref document: EP |