JP2006242581A - Tire uniformity correction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient tire uniformity correction method. <P>SOLUTION: Using a measured value or estimated value of the amount of RRO growth at a target speed and transmissibility thereof, high-speed RFV estimated value at the target speed is calculated. Using the transmissibility, a low-speed RFV corresponding value corresponding to the high-speed RFV estimated value and a low-speed RFV management upper-limit corresponding value corresponding to a high-speed RFV management upper-limit are determined in every order based on the estimated value and upper limit of the high-speed RFV. The corresponding value and the management upper-limit corresponding value of the low-speed RFV are compared with each other every order, and a low-speed RFV excess-part corresponding value exceeding the management upper-limit corresponding value of the corresponding value is determined. Further, a low-speed RFV excess-part estimated waveform corresponding to one tire round is determined based on the low-speed RFV excess-part corresponding value, and a low-speed RFV required correction-amount waveform showing a low-speed RFV required correction-amount based on the estimated waveform is determined. Then, correction target waveform of the low-speed RFV is determined by subtracting the low-speed RFV required correction-amount waveform from the low-speed RFV measured waveform acquired with the low-speed RFV measured value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tire uniformity correction method, and more particularly, to a tire uniformity correction method that is most suitable for buffing.

  In recent years, cases where high-order components of high-speed uniformity of tires become a problem as vibration noise phenomenon are increasing. On the other hand, there is a drawback that it takes time to actually measure and correct the high-order component of the high-speed uniformity of the tire. For this reason, a method for predicting high-order components of high-speed uniformity of tires has been proposed.

  For example, Patent Document 1 discloses a high-order component (for example, a second or higher order component) of a high-speed uniformity when the tire is rolling at a high speed based on a low-speed uniformity when the tire is rolling at a low speed. A method for predicting is disclosed. This method uses a drum with a mound cleat attached, and measures the vertical and longitudinal transmission characteristics of the tire, thereby providing high-speed RFV (radial force variation) and high-speed TFV (tangential force variation). ).

  However, in the above conventional technique, the amount of RRO (radial run-out) growth at high speed is not taken into consideration, and therefore an error in the predicted high-speed RFV may increase. There is a drawback that the effect of reducing TFV is not sufficient.

  As a countermeasure, Patent Document 2 discloses a high-speed RFV prediction method and a high-speed RFV prediction method in consideration of a high-speed RRO growth amount.

However, a method for efficiently correcting tire uniformity is not disclosed.
JP-A-11-352024 WO 03/034023 A1

  In view of the above facts, an object of the present invention is to provide an efficient tire uniformity correction method capable of sufficiently obtaining an effect of reducing RFV and TFV at high speed.

  The invention according to claim 1 is a step of calculating a high-speed RFV estimated value of the target speed using the RRO growth amount actual value or RRO growth amount estimated value of the target speed and the transmission rate, and using the transmission rate. For each order, a low-speed RFV equivalent value corresponding to the fast RFV estimate value and a low-speed RFV management upper limit value equivalent to the fast RFV management upper limit value are obtained from the fast RFV estimate value and the fast RFV management upper limit value. For each order, the low-speed RFV equivalent value and the low-speed RFV management upper limit equivalent value are compared, and the low-speed RFV excess equivalent value that exceeds the low-speed RFV management upper limit equivalent value among the low-speed RFV equivalent values. A low-speed RFV excess correction waveform for one round of the tire is obtained from the step of obtaining the low-speed RFV excess equivalent value, and a low-speed RFV necessary correction amount is indicated based on the low-speed RFV excess estimation waveform A step of obtaining an RFV necessary correction amount waveform and a step of obtaining a correction target waveform of the low-speed RFV by subtracting the low-speed RFV necessary correction amount waveform from the low-speed RFV necessary correction amount waveform obtained from the low-speed RFV actual measurement value. Features.

  For example, the following is performed in order to calculate the target RF high-speed RFV estimated value using the RRO growth actual measurement value of the target speed or the RRO growth estimated value and the transmission rate.

The relationship between the speed and RRO (radial run-out) is the tire angular speed of two levels (high speed H and low speed L) at idling or rotating at a predetermined load (for example, 500 N) or less at ω _H , ω _L , and radial run-out. When RRO _H and RRO _L are used, RRO _o given by the following equation (1) is used as an estimated RRO growth amount. It should be noted that the high speed is not as high as the target speed V _o .

  However,

Where V is the rotational speed of the tire and Re is the rolling radius of the tire. Note that ω _o = V _o / Re, and V _o is the above target speed.

Therefore, the relationship between the speed of each tire and the radial run-out is obtained by measuring the tire angular velocities ω _H , ω _L , radial run-out RRO _H , RRO _L , and the radial run-out at a low speed of each tire is measured. , it can be calculated radial run out RRO _o the radial run out and radial run-out in the measured low speed from the above relation that corresponds to the type of tire was measured at the target velocity V _o of.

  Further, the relationship between the speed for each tire and the radial run-out is obtained by measuring the radial run-out at a tire angular speed equal to or higher than the N + 1 level at the time of idling or rotating at a predetermined load (for example, 500 N) or less, Measure radial runout at low speed of each tire, and predict the radial runout at the target speed from the above-mentioned relationship corresponding to the type of measured tire and the radial runout at the low speed. it can.

The spring constant Kst in the vertical direction, the natural angular frequency ω _nz in the vertical direction, and the damping rate ζz can also be obtained by actual measurement.

The vertical spring constant Kst, the vertical natural angular frequency ω _nz , and the damping rate ζz are obtained for each tire type.

The natural angular frequency ω _nz and the damping rate ζz in the vertical direction may be calculated by the following two methods instead of actually measuring.

  In the first method, the natural angular frequency in the vertical direction is minimized so that the sum of squares of the difference between the prediction result of the vertical transfer characteristic and the transfer characteristic kz (ω) obtained by the following equation (2) is minimized. And a method of predicting the attenuation rate.

  The term having the root on the right side represents the displacement transmissibility of the primary damping system.

The second method is to extract three or more sample tires from the same lot, measure radial run-out and radial force variation at speeds of 3 levels or more (1 to M), and obtain a linear force variation primary obtained by Fourier transform. This is a method of predicting the natural angular frequency and the damping rate so that the sum of squares of the differences from the ~ _Nth order components RFV _{1 to} RFV _N is minimized.

However, M = 1, 2, 3,... N, and T _1z and T _MZ are displacement transmissibility expressed by the following equations, respectively.

When predicting the RFV _o at the target speed of each tire, the radial run-out RRO _{o at} the target speed V _o by the above calculation, the vertical spring constant Kst measured or calculated, and the natural angular frequency in the vertical direction Based on ω _nz and the damping rate ζz, the radial force variation RFV _o at the target speed is predicted according to the following equation (4).

T _oz representing the displacement transmission rate can be expressed by the following equation.

  Here, n is the order of Fourier transform, and Re is the rolling radius of the tire.

That is, the radial force variation is generated by transmitting a force generated by the deformation of the tire due to the radial force (contact load). The force transmission rate, that is, the displacement transmission rate is 1 at low speed, but changes as described above depending on the input frequency at high speed. Therefore, RFV _o, as shown in the above formula, the vertical spring constant, radial run out RRO at the target velocity V _o of _o, and is expressed by the product of the transfer rate of the displacement.

Further, when the low-speed RFV (RFV _L ) and RFV _o are expressed more accurately, they are expressed by the following equations.

  However, RSV is a rigidity fluctuation component, and d is a deformation amount of the tire. If RSV · d is eliminated from the above two equations, the following equation (5) is obtained.

T _LZ and T _{OZ in} the above equation (5) can be expressed by the following equations.

In the first aspect of the invention, after calculating the high-speed RFV estimated value (RFV _o ) of the target speed, the transmission rate used to calculate the RFV _o is used, and for each order, the RFV _o and the high speed of the target speed are calculated. From the RFV management upper limit value (RFV _o management upper limit value), a low speed RFV equivalent value corresponding to RFV _o and a low speed RFV management upper limit equivalent value corresponding to the RFV _o management upper limit value are obtained.

For example, low-speed RFV equivalent value is obtained by multiplying like the inverse of the transfer rate used for calculating the RFV _o the RFV _o, RFV the reciprocal of the transmission rate used for calculating the RFV _o upper control limit _{o A} low-speed RFV management upper limit equivalent value is obtained by multiplying the management upper limit value.

  Further, according to the first aspect of the present invention, the low speed RFV equivalent value and the low speed RFV management upper limit equivalent value are compared for each order, and the low speed RFV excess exceeding the low speed RFV management upper limit equivalent value among the low speed RFV equivalent values is exceeded. Find the minute equivalent value.

  Then, a low-speed RFV excess correction waveform for one round of the tire is obtained from the low-speed RFV excess equivalent value, and a low-speed RFV necessary correction amount waveform indicating a low-speed RFV necessary correction amount is obtained based on the low-speed RFV excess estimation waveform.

Further, the correction target waveform of the low-speed RFV (RFV _L ) is obtained by subtracting the low-speed RFV necessary correction amount waveform from the low-speed RFV actual measurement value waveform obtained from the low-speed RFV actual measurement value.

Accordingly, by correcting the tire uniformity by buffing or the like so that the corrected target waveform of the low-speed RFV is obtained, a sufficient reduction effect of RFV (RFV _o ) at high speed can be obtained.

  The invention according to claim 2 uses the RRO growth amount actual measurement value or RRO growth amount estimated value of the target speed and the transmission rate to calculate a high-speed TFV estimation value of the target speed, and uses the transmission rate. For each order, the low-speed AVV management upper limit value corresponding to the high-speed TFV management upper limit value and the low-speed AVV management upper limit value corresponding to the high-speed TFV management upper limit value are obtained from the high-speed TFV estimation value and the high-speed TFV management upper limit value. For each order, the low-speed AVV equivalent value and the low-speed AVV management upper limit equivalent value are compared, and among the low-speed AVV equivalent values, the low-speed AVV excess equivalent value exceeding the low-speed AVV management upper limit equivalent value is obtained. A low-speed AVV excess estimated waveform for one round of the tire is obtained from the step of obtaining and the low-speed AVV excess equivalent value, and a low-speed AVV necessary correction amount is indicated based on the low-speed AVV excess estimated waveform A step of obtaining an AVV necessary correction amount waveform, and a step of obtaining a low-speed AVV correction target waveform by subtracting the low-speed AVV necessary correction amount waveform from a low-speed AVV actual correction value waveform obtained from a low-speed AVV actual measurement value. Features.

  When the RRO growth amount estimated value is used, the method for calculating the RRO growth amount estimated value is not particularly limited as in the invention described in claim 1.

  To calculate the target speed high-speed TFV estimated value using the target speed RRO growth amount actual measurement value or the RRO growth amount estimated value and the transmission rate, for example, as follows.

  TFV (tangential force variation) is represented by the following equation.

Here, _Tox is the transmission rate of the displacement of the primary damping system at the target speed.

The term excluding the displacement transmission rate _Tox on the right side of the above equation is expressed by the following equation.

Accordingly, the target represented by a function including the radial run-out RRO _{o at} the actually-measured or predicted target velocity V _o , the natural angular frequency ω _nx in the front-rear direction calculated from the actual-measurement or measurement result, and the damping rate ζx. Based on the product of the displacement transmission rate T _OX of the primary damping system at the speed of, the radial run-out coefficient C _RRO , and the predicted tangential force variation coefficient C _TFV and the moment of inertia Iy, the following equation (6) Accordingly, the tangential force variation TFV _o of the target speed can be predicted.

(6) T _OX in the equation can be expressed by the following equation.

  The above-mentioned natural angular frequency and damping rate in the front-rear direction minimize the sum of squares of the difference between the prediction result of the front-rear direction transfer characteristic and the front-rear direction transfer characteristic kx (ω) calculated by the following equation: Thus, it can be predicted.

  However, a and b are coefficients.

The radial run-out coefficient C _RRO is obtained by extracting three or more sample tires from the same lot, measuring the radial run-out and angular acceleration fluctuations at low speed, and calculating the first to Nth angular acceleration fluctuations obtained by Fourier transform. can be a component AAV ₁ ~AAV _N, is the square sum of the difference between the primary ~N order component AAV ₁ ~AAV _N angular acceleration variation is calculated from the following equation to predict as a minimum.

Where V is the velocity, n is the order of Fourier transform, Re is the rolling radius, and _CRRO is the coefficient of RRO.

  When predicting the coefficient of radial runout, it is preferable to use the first to third order components having a speed of 30 km / h or less, which is less affected by the longitudinal resonance.

Further, the natural angular frequency in the front-rear direction, the damping rate, and the RRO coefficient C _RRO may be predicted as follows. That is, three or more sample tires are extracted from the same lot, radial run-out and angular acceleration fluctuations at speeds of 3 levels (1 to M) or more are measured, and primary to N-order components of angular acceleration fluctuations obtained by Fourier transform. AAV ₁ and ～AAV _N, as sum of squares of the differences between the primary ~N order component AAV ₁ ~AAV _N angular acceleration variation is calculated from the following equation is minimized, the coefficient C _RRO of radial run-out, the front-rear direction The natural angular frequency ω _nx and the damping rate ζx are predicted.

However, M = 1, 2, 3,... N, and T _1X and T _MX are given by the following equations.

The product of the coefficient C _TFV of the tangential force variation or the coefficient C _{TFV of the} tangential force variation and the moment of inertia can be predicted as follows. Extract three or more sample tires from the same lot, measure angular acceleration fluctuations and tangential force variations at high speeds, and obtain primary to _Nth order components TFV _{1 to} TFV N of tangential force variations obtained by Fourier transform. The coefficient of the tangential force variation or the coefficient of the tangential force variation and the coefficient of the tangential force variation are set so that the sum of squares of the difference between the primary to _Nth order components TFV _{1 to} TFV N of the tangential force variation calculated from the following formula is minimized. Predict the product with the moment of inertia.

Angular acceleration fluctuations to predict the product of radial run-out coefficient C _RRO and moment of inertia and tangential force variation coefficient C _TFV and moment of inertia generate signals corresponding to the rotary encoder and rotation angle on the tire axis. A device corresponding to the rotation angle of the tire is generated, and a frequency fluctuation rate FVR _R at the time of tire idling and a frequency fluctuation rate at the time of load by an FM modulator (or a device for detecting rotation unevenness) from this signal by generating a signal. After FVR _N is extracted and Fourier transformed, it can be measured by calculating angular acceleration fluctuation (AAV) based on the following equation.

  Note that all of the terms having the root in the above-described equation represent the displacement transmission rate of the primary damping system, but this displacement transmission rate may be given by other general formulas or approximate equations.

Further, based on the product of the angular acceleration variation AAV _o at the actual or predicted target velocity V _o , the predicted tangential force variation coefficient C _TFV and the moment of inertia Iy, The tangential force variation TFV _o of speed can be predicted.

The product of the coefficient C _TFV of the tangential force variation and the moment of inertia Iy and the angular acceleration fluctuation at the target speed are obtained as described above.

Note that the coefficient C _{TFV of the} tangential force variation may be used instead of the product of the coefficient C _TFV of the tangential force variation and the moment of inertia Iy.

Further, the target speed RRO _o may be calculated in the following manner.

First, the radial run-outs RRO _H and RRO _L of two levels (high speed H and low speed L) of the tire angular speeds ω _H and ω _L at the time of idling or rotating at a predetermined load (for example, 500 N) or less are measured. This is a method for predicting the radial run-out RRO _o at the target speed based on the equation (1).

  Second, a method of measuring a radial runout at a tire angular speed equal to or higher than the N + 1 level during idling or rotating at a predetermined load (for example, 500 N) or less and predicting a radial runout at a target speed by an Nth order regression equation. It is.

  In order to estimate the tire angular acceleration fluctuation (AAV), for each tire type, a process of obtaining a radial run-out coefficient based on the natural angular frequency in the front-rear direction, the damping rate, and the angular acceleration fluctuation; Based on the radial runout measurement process, the radial runout calculation for each tire at the target speed, the natural angular frequency in the vertical direction, the damping factor, the radial runout coefficient, and the radial runout at the target speed. And a step of predicting the angular acceleration fluctuation at the speed of.

That is, the radial run-out RRO _{o of} the target speed V _o predicted as described above, the natural angular frequency ω _nx in the front-rear direction calculated from the actual measurement or the measurement result as described above, the damping rate, and based on the coefficients of the radial run-out, it is to predict the angular acceleration fluctuation AAV _o of the target speed in accordance with the following equation (8).

  Further, the tire angular acceleration fluctuation may be estimated as follows. That is, for each tire type, the step of obtaining the national angular frequency, the damping rate, and the radial runout coefficient in the front-rear direction, the step of measuring the radial runout at low speed and the angular acceleration fluctuation at low speed of each tire, Based on the process of determining the radial runout at the target speed of the tire and the natural angular frequency in the longitudinal direction, the damping rate, the coefficient of the radial runout, the radial runout at the target speed, and the angular acceleration fluctuation at low speed, the target speed The angular acceleration fluctuation at may be predicted.

That is, the measured values RRO _L and AAV _L of the radial run-out and angular acceleration fluctuation at low speed, the radial run-out RRO _{o of} the target velocity V _o predicted as described above, and converted from the measured or measured results as described above. Based on the calculated natural angular frequency ω _nx , damping factor ζx, and radial runout coefficient, the angular acceleration fluctuation of the target speed is predicted according to the following equation.

  Further, the angular velocity fluctuation of the target velocity is predicted according to the following formula.

Here, T _OX and T _LX are given by the following formulas, and are displacement transmission rates of the primary damping system at the target speed and low speed, respectively.

  The data obtained for each tire type of each invention is preferably stored in a storage device and constructed as a database. By constructing as a database, it is possible to efficiently predict radial force variation, tangential force variation, or angular acceleration variation of various tires.

In the invention according to claim 2, after calculating the high speed TFV estimated value (TFV _o ) of the target speed, the transmission rate used to calculate TFV _o is used, and the TFV _o and the high speed of the target speed are calculated for each order. TFV upper control limit from (TFV _o upper control limit), the low-speed AVV equivalent value corresponding to the TFV _o, and obtains a low-speed AVV upper control limit corresponding value corresponding to the TFV _o upper control limit.

For example, low-speed AVV equivalent value is obtained by multiplying like the inverse of the transfer rate used to calculate the TFV _o the TFV _o, TFV the reciprocal of the transmission rate used for calculating the TFV _o upper control limit _{o A} low-speed AVV management upper limit equivalent value is obtained by multiplying the management upper limit value or the like.

  Further, according to the second aspect of the present invention, the low speed AVV equivalent value and the low speed AVV management upper limit equivalent value are compared for each order, and the low speed AVV excess exceeding the low speed AVV management upper limit equivalent value among the low speed AVV equivalent values is compared. Find the minute equivalent value.

  Then, a low-speed AVV excess estimated waveform for one round of the tire is obtained from the low-speed AVV excess equivalent value, and a low-speed AVV necessary correction amount waveform indicating the low-speed AVV necessary correction amount is obtained based on the low-speed AVV excess estimation waveform.

Furthermore, a low-speed AVV (AVV _L ) correction target waveform is obtained by subtracting the low-speed AVV required correction amount waveform from the low-speed AVV actual measurement value waveform obtained from the low-speed AVV actual measurement value.

Accordingly, by correcting the tire uniformity by buffing or the like so that the corrected target waveform of the low-speed AVV is obtained, a sufficient reduction effect of TFV (TFV _o ) at high speed can be obtained.

  According to a third aspect of the present invention, at least the addition of the buff polishing amount in the RRO increase phase and the subtraction of the buff polishing amount in the RRO decrease phase based on the actual RRO growth amount or the estimated RRO growth amount. It is characterized by doing one.

  In the invention according to claim 3, the estimated value (or actual measurement) of the RRO growth amount from low speed to high speed without actually rotating at high speed on the existing buffing (polishing) type correction device that improves the roundness of low speed. By increasing or decreasing the buffing (polishing) amount based on the value), it is possible to obtain the effect of improving the roundness during high-speed rotation.

  Since the present invention has the above-described configuration, the tire uniformity can be corrected efficiently, and the effect of reducing RFV and TFV at high speed can be sufficiently obtained.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described.

[First Embodiment]
First, the measuring device used in this embodiment will be described. FIG. 1 shows an RRO measuring apparatus capable of measuring radial run-out (RRO) with less influence of lug grooves. This measuring device is composed of a light irradiating unit 30 configured by an LED for irradiating light, and a light receiving unit 32 configured by a CCD for receiving light irradiated from the light irradiating unit 30, and is twisted and irradiated. The light irradiation unit 80, the light receiving unit 32, and the tire are arranged so that the light beam comes into contact with the outer periphery of the tire that is the object to be measured, and the RRO is measured from the change in the amount of light received by the light receiving unit 32. In addition, as a RRO measuring apparatus, the dimension measuring apparatus LS-7030 (the Keyence company make, brand name) can be used.

  FIG. 2 shows a tire angular acceleration fluctuation (AAV) measuring apparatus. This AAV measuring apparatus includes a rotary encoder 34 that is attached to a tire shaft and generates a pulse signal in accordance with the rotation angle of the tire, a frequency fluctuation rate FVRR at tire idling and a frequency fluctuation rate F VRN at load from the pulse signal. And an FM modulator 36 for extracting. As the rotary encoder, an encoder MEH-85-1024 (manufactured by Microtech Laboratories, product) can be used, and as the FM modulator, Flutter Analyzer Mode 16110A (manufactured by Act Electronics Co., Ltd., product name) can be used.

[Prediction process of high-speed RFV and high-speed TFV of target speed]
Next, predict the target speed fast RFV (RFV _o ) and fast TFV (TFV _o ) (ie, calculate the target speed fast RFV estimate (RFV _o ) and fast TFV estimate (TFV _o )). And, it will be described with reference to FIG. 3 and the like that the tire uniformity is corrected before shipment.

The natural angular frequency and damping rate of a tire are not different for each tire, but are different for each type of tire (size, specification). Therefore, in order to predict RFV _o , characteristic values of a plurality of tires in the same lot are used. The natural angular frequency, the damping rate, etc. are predicted from the data and stored in the database. That is, in step 100, three or more sample tires are extracted from the same lot, and RRO and RFV at a speed of 3 levels or more (1 to M) are measured. An example of the measured RFV value is shown in FIG.

Further, a primary ~N following components RFV ₁ ～RFV _N of RFV obtained by Fourier transform, the square sum is minimum difference between the primary ~N following components RFV ₁ ～RFV _N of RFV which is calculated from the following equation Thus, the coefficients of the vertical and longitudinal natural angular frequencies, the damping rate, the vertical spring constant, and the rolling radius are predicted and stored in the database by the method of least squares.

However, M = 1, 2, 3,... N, and T _1Z and T _MZ are each expressed by the following equations.

Where V is the speed, n is the order of the Fourier transform, ω _nz is the natural angular frequency, Re is the rolling radius of the tire, Kst is the upper and lower spring constant, and ζz is the damping factor.

  Fig. 4 shows the measured and predicted RFV values when using the PSR205 / 65R15 tires used in the least square method, and Fig. 5 shows the least squares when using the same tires. The actual measured value and predicted value (estimated value) of AAV used for the multiplication are shown.

Further, in order to predict a high-speed TFV, the product of the coefficient TFV of _TFV and the moment of inertia is also stored in the database. The product of the coefficient C _TFV and the moment of inertia of the tangential force variation is obtained by extracting three or more sample tires from the same lot, measuring angular acceleration fluctuation and TFV at high speed, and obtaining the first-order TFV obtained by Fourier transform. ~N as the sum of squares of the difference between the following components TFV _l ~TFV _N and primary ~N following components TFV ₁ ～TFV _N of TFV which is calculated from the following equation is minimized, the coefficient of TFV by the least square method C _Predicts the product of _TFV and inertia moment.

  FIG. 6 shows measured values of TFV used in the least square method and predicted values (estimated values) of TFV predicted from AAV based on the above formula.

In step 102, radial runouts RRO _H and RRO _L at two levels (at high speed H and low speed L) of tire angular velocities ω _H and ω _L during idling are measured using the RRO measuring device shown in FIG. The measured value AAV _L of the angular acceleration fluctuation at low speed is measured using the AAV measuring apparatus shown in FIG.

In the next step 104, the radial run-out RROo at the target speed is predicted according to the following equation based on the actual measured values RRO _H and RRO _L of the high and low speeds. Note that the radial run-out RRO _o at the target speed may be actually measured using the RRO measuring device shown in FIG.

  However, ω = V / Re.

  Note that the radial run-out at the tire angular speed equal to or higher than the N + 1 level at the time of idling or rotating at a predetermined load (for example, 500 N) or less is measured, and the radial run-out at the target speed is predicted by the Nth order regression equation. Also good.

In step 104, the measured values RRO _L and AAV _L of the radial run-out and angular acceleration fluctuation at low speed, the radial run-out R RRO _o of the target velocity V _o calculated as described above, and measured as described above. Alternatively, based on the natural angular frequency ωnx, the damping rate ζx, and the radial runout coefficient calculated by conversion from the measurement result, the angular acceleration fluctuation of the target speed is predicted according to the following equation.

Here, T _OX and T _LX are transmission rates of displacement of the primary damping system at the target speed and low speed, respectively.

  FIG. 7 shows measured values and predicted values (estimated values) of RRO at low speed (15 km / h) and high speed (100 km / h), and FIG. 8 shows AAV values at low speed (15 km / h). An actual measurement value and a predicted value (estimated value) are shown.

  In addition, you may make it predict the angular velocity fluctuation | variation of a target speed using (8) Formula.

On the other hand, since the tire uniformity value is different for each tire even if the tire type is the same, RFV _o and RFV _o are predicted for each tire in step 106.

In this embodiment, RFV at the target speed. Is the Fourier transform result of the radial run-out RRO _o at the target speed V _o predicted as described above, the vertical spring constant Kst calculated from the actual measurement or the measurement result, and the displacement transmission rate T of the primary damping system. Based on _OZ , prediction was made according to the following formula:

Note that the RFV _o at the target speed may be predicted based on the equation (5). Here, (RRO _o −RRO _L ) in the equation (5) is the RRO growth amount. As the RRO growth amount, an RRO growth amount estimated value (RRO growth amount predicted value) may be used, or an RRO growth amount actual measurement value may be used. Fig. 17-2 shows the measured RRO growth for one tire. Moreover, a high-speed RFV estimated value (RFV _o ) is shown in FIG.

Also, high speed TFV is the angular acceleration fluctuation AAV _o in the rate V _o of the predicted target as described above, based on the product of the coefficient C _TFV and moment of inertia Iy of TFV stored in the database, the following formula To predict the TFV _o at the target speed.

FIG. 9 shows predicted values and measured values of the primary to tertiary components of RFV _o predicted from the measured value (RFV _L ) of RFV at a low speed (15 km / h), and FIG. 10 shows the value of TFV _o . The predicted values and measured values of the primary to tertiary components are shown.

  FIG. 11 shows the correlation between the RFVl-order to tertiary measured values and the predicted values, and FIG. 12 shows the correlation between the TFVl-order to tertiary measured values and the predicted values.

Note that the predicted value TFV _o may be predicted according to the equation (6).

In the next step L08, compares each of the RFV _o and TFV _o and the reference value, and selecting a tire larger than RFV _o and TFV _o is the reference value, the greater the tire than RFV _o and TFV _o is the reference value, for example, The radial run-out (RRO) is corrected and shipped, and the tires with higher-order components of RFV _o and TFV _o smaller than the standard value are shipped as they are properly manufactured.

  In step 110, it is determined whether or not the sorting has been completed. If it has been completed, this method is terminated.

Note that the natural angular frequency ω _nz in the vertical direction and the damping rate ζz may be obtained from the measured values of the overpass tester in FIG. As shown in FIG. 13, the protrusion overpass tester includes a drum 10 having an FRP cleat 12 attached to the surface and a sensor 16 attached to the tip of a dedicated stand 14.

  The sensor 16 includes an axial force sensor (three-direction axial force sensor) 16A configured by a load cell that detects the tire vertical axial force Fz, and a displacement sensor configured by a laser displacement meter that detects displacement of the tire shaft relative to the drum surface. 16B is provided.

  The axial force sensor 16A and the displacement sensor 16B are connected to a personal computer 20 as a prediction device to which a CRT 18 as a display device for displaying measurement data and the like is connected.

  When measuring the transmission characteristic in the tire vertical direction at the time of rolling, an input is given to the tire shaft in the vertical direction by bringing the tire into contact with the drum 10 and rotating the drum. The vertical axial force Fz of the tire at that time is measured by the axial force sensor 16A, and the vertical displacement X of the tire shaft relative to the drum surface is measured by the displacement sensor 16B.

  Then, the personal computer 20 calculates the transfer characteristic Fz / X of the tire vertical axial force Fz with respect to the vertical displacement X of the tire shaft.

  When measuring the transmission characteristics in the tire longitudinal direction at the time of rolling, input in the longitudinal direction by contacting the drum with a load applied to the tire and rotating the drum in the protrusion overriding tester in FIG. And the longitudinal axial force Fx of the tire at that time is measured by the axial force sensor 16A. At this time, the vertical displacement X of the drum surface is measured by the displacement sensor 16B. Then, the transfer characteristic Fx / X is predicted.

  The natural angular frequency in the vertical direction so that the sum of squares of the difference between the prediction result of the vertical transfer characteristic obtained as described above and the transfer characteristic kz (ω) obtained by the following equation is minimized. And predict the decay rate.

  FIG. 14 shows the measured values of the cleat overriding of the overpass tester and the natural vibration and damping rate calculated from the measured values based on the above formula, and FIG. 15 shows the converted values calculated by the following formula. The natural vibration and damping rate are shown.

  However, a and b are coefficients.

Although accuracy is deteriorated, RFV _o and TFV _o can be predicted only from RRO during idling.

As described above, in the RFV _o and TFV _o prediction process, low-speed RRO, AAV, and idling RRO (speed 2 level) are measured by simple forwarding, and RFV _o and TFV _o are predicted to increase the speed. As compared with the case where the uniformity testing machine is introduced, the tire selection according to RFV _o and TFV _o can be achieved with less equipment investment.

In the above description, the example of measuring RRO _o has been described. However, as described above, RRO _o may be predicted from the low-speed RRO. FIG. 16 shows the estimation results of the RRO primary to tertiary components up to the speed of 140 km / h using the data of the speeds of 30, 50, and 70 km / h and the measured results of the RRO primary to tertiary components. Even from data on the low speed side up to a speed of 30 km / h, an RRO at a speed of 120 km / h is obtained with a maximum error of about 0.02 mm.

[Calculation step of low-speed RFV equivalent value, low-speed RFV management upper limit equivalent value, low-speed AVV equivalent upper-limit value, and low-speed AVV management upper-limit equivalent value]
Furthermore, in this embodiment, RFV is obtained by the prediction process. Is calculated for each order from the RFV _o and RFV _o management upper limit values, the low-speed RFV equivalent value corresponding to RFV _o and the low-speed RFV management upper limit equivalent value corresponding to the RFV _o management upper limit value.

Where RFV. Is predicted based on the equation (5), the low-speed RFV equivalent value RFV _eqL can be calculated by the following equation using the reciprocals of the transmission rates T _LZ and T _OZ used in the equation (5).

By transforming this equation, the low-speed RFV equivalent value RFV _eqL is calculated as follows.

An example of the low-speed RFV equivalent value RFV _eqL for one round of the tire calculated for each order is shown in FIG. 17-4.

Further, the high-speed RFV management upper limit value RFV _U is determined by specifications (for example, the high-speed RFV primary component is PP value of 100 N). Using this RFV management upper limit value RFV _U , the low-speed RFV management upper limit equivalent value RFV _eqLU can be calculated as follows.

An example of the calculated low-speed RFV equivalent value RFV _eqL and the low-speed RFV management upper limit equivalent value RFV _eqLU is shown in FIG.

In this embodiment, after calculating TFV _o, for each order, from the TFV _o and TFV _o management upper limit values, the low-speed AVV equivalent value corresponding to TFV _o and the low-speed AVV corresponding to the TFV _o management upper limit value are obtained. The management upper limit equivalent value is obtained.

Here, when TFV _o is predicted based on the equation (6), the low-speed AVV equivalent value AVV _eqL can be calculated by the following equation using the reciprocal of the transmission rate T _OX used in the equation (6). .

By transforming this equation, the low-speed AVV equivalent value AVV _eqL is calculated as follows.

The high-speed TFV management upper limit value TFV _U is determined by specifications (for example, the high-speed TFV primary component is a PP value of 100 N). Using this high-speed TFV upper control limit TFV _U, slow AVV upper control limit value corresponding AVV _EqLU can be calculated as follows.

[Calculation process for low-speed RFV excess value and low-speed AVV excess value]
Further, in the present embodiment, for each order, by comparing the low-speed RFV value corresponding RFV _EQL and slow RFV upper control limit value corresponding RFV _EqLU, beyond the slow RFV upper control limit value corresponding RFV _EqLU of slow RFV value corresponding RFV _EQL The value corresponding to the excess low speed RFV is obtained.

In this embodiment, the low-speed AVV equivalent value AVV _eqL and the low-speed AVV management upper limit equivalent value AVV _eqLU are compared for each order, and the low-speed AVV equivalent upper value AVV _eqLU out of the low-speed AVV equivalent value AVV _eqL is exceeded. The low-speed AVV excess equivalent value is obtained.

[Calculation process of low-speed RFV required correction amount waveform and low-speed AVV required correction amount waveform]
Furthermore, a low-speed RFV excess estimated waveform for one round of the tire is obtained from the low-speed RFV excess equivalent value, and a waveform indicating the low-speed RFV necessary correction amount indicating the low-speed RFV necessary correction amount is obtained based on the low-speed RFV excess estimation waveform. FIG. 17-5 shows a waveform indicating the necessary low-speed RFV correction amount for each order calculated in this way.

  In addition, a low-speed AVV excess correction waveform indicating the low-speed AVV required correction amount is obtained based on the low-speed AVV excess correction waveform based on the low-speed AVV excess correction waveform.

[Calculation process of low-speed RFV correction target waveform and low-speed AVV correction target waveform]
Further, by subtracting the waveform indicating the low-speed RFV necessary correction amount from the waveform indicating the low-speed RFV actual measurement value (RFV _L ), as shown in FIG. 17-5, the waveform indicating the correction target of the low-speed RFV by buffing (low-speed RFV). (Waveform showing RFV buff target).

Further, the low-speed AVV correction target waveform is obtained by actually measuring the low-speed AVV in advance and subtracting the low-speed AVV necessary correction amount waveform from the low-speed AVV actual measurement value waveform obtained from the low-speed AVV actual measurement value (AVV _L ).

  Then, considering the correction target waveform of the low-speed RFV and the correction target waveform of the low-speed AVV, the tire uniformity is corrected by buffing, so that a sufficient RFV reduction effect at high speed can be obtained.

Thereby, according to this embodiment, the tire uniformity can be corrected efficiently, and the effect of reducing RFV and TFV at high speed can be sufficiently obtained. In addition, since there is no need to perform a buffing so that the corrected target waveform of RFVo, there is no need to perform the difficult task of check and fix RFV _o waveform after buffing.

In addition, as an RFV measuring apparatus that measures low-speed RFV (RFV _L ), an RFV measuring apparatus that has a buffing function and can set a correction target waveform of low-speed RFV may be used. This makes it possible in a short time and with high precision uniformity correction corresponding to the RFV _o. Similarly, as an AVV measuring apparatus that measures low-speed AVV (AVV _L ), an AVV measuring apparatus that has a buffing function and can set a corrected target waveform of low-speed AVV may be used. Thus, it is possible to perform uniformity corrected in a short time and with high precision uniformity correction corresponding to the AVV _o. Moreover, you may use the measuring apparatus provided with both the RFV measurement function and the AVV measurement function.

  Alternatively, only one of the corrected target waveform for low-speed RFV and the corrected target waveform for low-speed AVV may be calculated, and buffing may be performed so that one calculated target waveform is obtained.

[Second Embodiment]
Next, a second embodiment will be described. The present embodiment differs from the first embodiment in the process of predicting the target speeds RFV _o and TFV _o . Accordingly, in the present embodiment, described prediction process of RFV _o and TFV _o, it will not be described other.

As described in the equations (9) and (16) above, in order to predict the target speed RFV _o and TFV _o , the target speed tire tread radial runout (RRO _o ), the low speed RFV The RRO of the tire tread portion during measurement and during low-speed AAV measurement is required.

In the present embodiment, in order to prevent the influence of tire bearing rattling or the like and the subtle vibration of the rim reference surface relative to the tire bearing from affecting the RFV and TFV prediction accuracy, As RRO, a predicted value of RRO _o of a tire unit having a target speed is used. This predicted value is given by the above equation (2).

  Further, as the RRO of the tire tread portion at the time of low-speed RFV measurement and at the time of low-speed AAV measurement, the radial of the hub portion which is the rim concentric circle portion measured at the time of the RFV measurement and the AAV measurement is added to the RRO of the low-speed tire alone. A value obtained by adding run-out is used.

First, the measurement device used in the present embodiment is the same as the measurement device (see FIGS. 1 and 2) in the first embodiment described above, and thus the description thereof is omitted. In the AAV measuring apparatus shown in FIG. 2, AAV is measured from the frequency variation rate FVR _R and the frequency variation rate FVR _N.

  FIG. 18 shows a measuring apparatus for measuring RRO of the rim concentric circles. A displacement sensor 46 for measuring the displacement up to the outer peripheral surface of the hub (rim-attached tire attachment surface) 44 of the offset zero portion is attached to the tire bearing national fixed portion 40 via a stay 42 for attaching the sensor. Reference numeral 48 denotes a tire.

  By measuring the displacement of the portion of the rim concentric part where there is no offset of the hub, this measuring device can measure the RRO of the rim concentric part.

  FIG. 19 shows a measuring apparatus for measuring both the RRO of the rim concentric circle and the RRO of the drum. This measuring apparatus includes a pair of rim displacement sensors 50A and 50B that measure the displacement of the rim concentric portion from the reference position, and a pair of drum displacement sensors 52A and 52B that measure the displacement of the drum concentric portion from the reference position. It has. Each displacement sensor 50A, 50B, 52A, 52B is fixed to a stationary portion of the measuring device via a mounting stay 42, respectively.

  In addition, this measuring apparatus is provided with a drum 54 that comes into contact with the tire in order to measure RRO and the like.

  The rim displacement sensors 50A and 50B are fixed so as to measure the displacement at the symmetrical position of the rim flange with the offset zero portion interposed therebetween, and the drum displacement sensors 52A and 52B are the rim displacement sensors with the offset zero portion interposed therebetween. It is fixed so as to measure the part opposite to the part to be measured.

  According to this measuring apparatus, the displacement measured by the rim displacement sensor can be averaged to calculate the displacement of the offset zero portion of the rim concentric circle, that is, the RRO of the rim concentric circle. By averaging the measured displacements, the displacement of the offset zero portion of the drum concentric circle portion, that is, the RRO of the rim concentric circle portion can be calculated.

Then, to predict the RFV _o and TFV _o, an embodiment of a method of manufacturing tires sorted based tires produced in the predicted values of the RFV _o and TFV _o, ship and correct the RRO optionally This will be described with reference to the flowchart of FIG.

Rim assembly tire's natural angular frequency, damping rate, upper / lower screw constant, rolling radius and other factors are not different for each rim assembly tire, but the type of rim assembly tire (size, spec) vary from, because the same type of rim assembling the tire is the same, by predicting natural angular frequency and the damping ratio and the like from the characteristic values of a plurality of rim assembling the tire in the same lot in order to predict the RFV _o Store in the database.

That is, in step 200, three or more sample tires are extracted from the same lot, RRO and RFV at speeds of 3 levels or more (1 to M) are simultaneously measured, and the primary to Nth order components of RFV obtained by Fourier transform. RFV ₁ ～RFV _N and, as the sum of squares of the difference between the primary ~N following components RFV ₁ ～RFV _N of RFV which is calculated from the following equation is minimized, specific vertical and longitudinal directions by the least square method Coefficients such as angular frequency, damping rate, up / down constant, and rolling radius are predicted and stored in the database.

However, MI1, 2, 3,... N, and T _1Z and T _MZ are each expressed by the following equations.

  Where V is the speed, n is the order of Fourier transform, ωnz is the natural angular frequency, Re is the rolling radius of the tire, Kst is the upper and lower spring constant, and ζz is the damping factor.

  On the other hand, the uniformity value of the tire is different for each tire even if the type of the rim-attached tire is the same. In step 202, simple data measurement is performed, and the low speed of the rim-attached tire to be measured is measured. The RFV and the RRO of the rim concentric circles are simultaneously measured, and the RRO of each of the tire tread and the rim concentric circles is measured at a low speed and a high speed. The RFV at low speed can be measured using a conventionally known RFV measuring device, and the RRO of the rim concentric circle can be measured using the measuring device described in FIG. 18 or FIG.

Further, the RRO of each of the tire tread and the rim concentric circles at the low speed and the high speed is the tire angular speed ω _H of two levels (at the time of high speed H and low speed L) at the time of idling using the RRO measuring device shown in FIG. , Ω _L , radial run-out TreRRO _H , TreRRO _Lト and rim concentric radial run-out RimRRO _H , RimRRO _L can be obtained.

Furthermore, the measured value AAV _L of the angular acceleration fluctuation at low speed is measured using the AAV measuring apparatus shown in FIG. At this time, at the same time as measuring the low speed AAV, the RRO in the rim concentric part is measured using the measuring apparatus described in FIG. 18 or FIG.

In the next step 204, based on the tire radial velocities ω _H and ω _L measured in step 202, the tread radial run-outs TreRRO _H and TreRRO _L and the rim concentric radial run-outs RimRRO _H and RimRRO _L according to the following formula: to predict the radial run out RRO _o of the tire itself in.

However,

It is.

  21A shows the primary radial runout of the tire tread, FIG. 21B shows the primary radial runout of the rim concentric circle, and FIG. 21C shows the primary radial runout of the tire tread from the rim concentric circle. The primary radial runout of a single tire obtained by subtracting the primary radial runout is shown. As understood from the figure, the first-order radial run-out of a single tire obtained by subtraction as described above is required so as to reduce fluctuation.

Further, in FIG. 24, the predicted value of the radial run-out RRO _o of the single tire at the target speed predicted using the actual measured value of 15 km / h and the actual measured value of 80 km / h is shown by a solid line, and the radial run-out RRO of the single tire is shown. Measured values (15, 50, 80, 100, and 120 km / h) are indicated by dots. As can be understood from the figure, an increasing tendency of the radial run-out RRO of a single tire having a speed of 80 km / h or more can be predicted even from two measurement data having a speed of 80 km / h or less.

In step 206, RFV _o is predicted according to the above equation (9), and TFV _o is predicted for each rim-attached tire according to the above equation (16). FIGS. 22A to 22C show the correlation between the measured values of the primary to tertiary components of RFV and the predicted values of the primary to tertiary components of RFV _o at high speed (120 km / h). 23 (A) to (C) show the correlation between the measured values of the primary to tertiary components of TFV _o and the predicted values of the primary to tertiary components of TFV _o at high speed (120 km / h).

In the next step 208, each comparing the predicted RFV _o and TFV _o and the reference value, RFV _o and TFV _o is sorted rim assembling the tire higher than the reference value, RFV _o and TFV _o is the reference value For large rim-assembled tires, for example, the radial run-out (RRO) is corrected and shipped, and rim-assembled tires with higher-order components of RFV _o and TFV _o smaller than the standard value are shipped as they are properly manufactured. .

  In step 210, it is determined whether or not the sorting has been completed. If it has been completed, this method is terminated.

  25 and 26 show the measured values (15, 50, 80, 100, and 120 km / h) of RFV and TFV with dots, and the predicted values of RFV and TFV (the tire alone at high speed obtained above). RRO, determined using 15 km / h RFV and AAV).

  As understood from the figure, it is possible to predict an increasing tendency of RFV and TFV at a speed of 50 km / h or higher even from one measurement data at a speed of 15 km / h or lower.

  Also in the present embodiment, the natural angular frequency ωnz in the vertical direction and the damping rate ζz can be obtained as described above from the measured values of the projection overpass tester (see FIG. 13) in the first embodiment described above. Good.

As described above, according to this embodiment, in the RFV _o and TFV _o prediction steps, the RRO of the rim concentric circle part and the RRO of the tire tread part are simultaneously measured, and the RRO rim concentric circle part RRO of the tire tread part is measured. By subtracting, the RRO of the tire alone at high speed is predicted, and the RFV and TFV at high speed are predicted using the predicted RRO of the tire alone at high speed. The effect that it can prevent is acquired.

  Further, since the RFV and TFV of a single tire at high speed are predicted using the predicted RRO of the single tire at high speed as the RRO at the time of measuring low speed RFV and low speed AAV, the influence due to a decrease in rim mounting accuracy is prevented. The effect that it can be obtained.

Also, RFV _o and TFV _o can be predicted with higher accuracy by correcting the RRO of the tire tread during low-speed RFV measurement or low-speed AAV measurement in consideration of the RRO of the drum that comes into contact with the tire during RFV measurement. can do.

  In addition, considering the uneven rotation of the rim-assembled tire that accelerates or decelerates via the driving stiffness from the road surface, the angular acceleration fluctuation, which is an upper factor of TFV generated at high speeds, is newly corrected by adding a driving stiffness term. For example, it is possible to reduce the difference between the predicted value and the actual measurement value of the high-speed TFV by a simple method while reducing the number of parameters.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. Needless to say, the scope of rights of the present invention is not limited to the above embodiment.

It is the schematic of a RRO measuring device. It is a schematic diagram of an AAV measuring device. It is a flowchart which shows the prediction process of 1st Embodiment. It is a diagram which shows the measured value and predicted value of RFV. It is a diagram which shows the measured value and predicted value of AAV. It is a diagram which shows the actual value of TFV, and the predicted value of TFV estimated from AAV. It is a diagram which shows the measured value and estimated value of RRO. It is a diagram which shows the measured value and predicted value of AAV. It is a diagram which shows the predicted value and measured value of the 1st-3rd order component of high-speed RFV estimated from the measured value of RFV. It is a diagram which shows the predicted value and measured value of the 1st-3rd-order component of the estimated high-speed TFV. It is a diagram which shows the correlation with the measured value of RFVl order-3rd order, and a predicted value. It is a diagram which shows the correlation with the measured value of TFVl order-3rd order, and a predicted value. It is the schematic of a protrusion overpass tester. It is a diagram which shows the natural vibration and damping factor which were calculated from the measured value of the cleat riding over the protrusion passing tester, and this measured value. It is a diagram which shows the natural vibration and damping factor which were calculated by the other type | formula. It is a diagram which compares and shows the estimation result of RRO primary-tertiary component, and the measurement result of RRO primary-tertiary component. It is a diagram which shows the waveform of the low-speed RFV measured value about one tire circumference. It is a diagram which shows the waveform of the RRO growth amount actual measurement value about one tire circumference. It is a diagram which shows the waveform of the high-speed RFV estimated value about tire one round. It is a diagram which shows the waveform of the low-speed RFV equivalent value about one tire circumference. It is a diagram which shows the correction amount waveform of the low speed RFV about the tire circumference, and the correction target waveform of the low speed RFV. It is the schematic of the measuring apparatus which measures RRO of a rim concentric circle part. It is the schematic of the measuring apparatus which measures both RRO of a rim concentric circle part, and RRO of a drum. It is a flowchart which shows the prediction process of 2nd Embodiment. (A) is the primary radial runout of the tire tread, (B) is the primary radial runout of the rim concentric circle, and (C) is the primary radial runout of the rim concentric circle from the primary radial runout of the tire tread. It is a diagram which shows the primary radial runout of the tire single-piece | unit calculated | required by subtraction. (A)-(C) is a diagram showing the correlation between the measured values of the first to eighth order components of RFV at high speed (120 km / h) and the predicted values of the first to third order components of high speed RFV. It is. (A)-(C) is a diagram which shows the correlation with the measured value of the primary-tertiary component of TFV in high speed (120 km / h), and the predicted value of the primary-tertiary component of high-speed TFV. . FIG. 4 is a diagram showing a predicted value of a radial run-out RRO _o of a tire alone and an actual measured value of a radial run-out RRO of a single tire at high speed predicted using an actual measured value of 15 km / h and an actual measured value of 80 km / h. . It is a diagram which shows the actual value of RFV, and the predicted value of RFV. It is a diagram which shows the actual value of TFV, and the predicted value of TFV.

Explanation of symbols

48 tires

Claims (3)

A step of calculating a high-speed RFV estimation value of the target speed using the RRO growth amount actual measurement value or the RRO growth amount estimation value of the target speed and the transmission rate;
Using the transmission rate, for each order, from the high-speed RFV estimated value and the high-speed RFV management upper limit value, a low-speed RFV equivalent value corresponding to the high-speed RFV estimated value and a low-speed RFV management corresponding to the high-speed RFV management upper limit value Obtaining an upper limit equivalent value;
For each order, the low-speed RFV equivalent value and the low-speed RFV management upper limit equivalent value are compared to determine a low-speed RFV excess equivalent value that exceeds the low-speed RFV management upper-limit value among the low-speed RFV equivalent values; ,
Obtaining a low-speed RFV excess correction waveform for one round of the tire from the low-speed RFV excess equivalent value, and obtaining a low-speed RFV necessary correction amount waveform indicating a low-speed RFV necessary correction amount based on the low-speed RFV excess estimation waveform;
Subtracting the low-speed RFV required correction amount waveform from the low-speed RFV actual measurement value waveform obtained from the low-speed RFV actual measurement value to obtain a low-speed RFV correction target waveform;
A tire uniformity correction method comprising: A step of calculating a high speed TFV estimation value of the target speed using the RRO growth amount actual measurement value or the RRO growth amount estimation value of the target speed and the transmission rate;
Using the transmission rate, for each order, from the high-speed TFV estimated value and the high-speed TFV management upper limit value, the low-speed AVV equivalent value corresponding to the high-speed TFV estimated value and the low-speed AVV management corresponding to the high-speed TFV management upper limit value Obtaining an upper limit equivalent value;
For each order, comparing the low-speed AVV equivalent value and the low-speed AVV management upper limit equivalent value to obtain a low-speed AVV excess equivalent value exceeding the low-speed AVV management upper-limit value among the low-speed AVV equivalent values; ,
Obtaining a low-speed AVV excess estimated waveform for one round of the tire from the low-speed AVV excess equivalent value, and obtaining a low-speed AVV necessary correction amount waveform indicating a low-speed AVV necessary correction amount based on the low-speed AVV excess estimation waveform;
Obtaining a low-speed AVV correction target waveform by subtracting the low-speed AVV required correction amount waveform from a low-speed AVV actual measurement value waveform obtained from the low-speed AVV actual measurement value;
A tire uniformity correction method comprising:   A tire that performs at least one of addition of a buffing amount in an RRO increase phase and subtraction of a buffing amount in an RRO decrease phase based on an actual RRO growth amount or an estimated RRO growth amount Uniformity correction method.

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