JPH08159906A - Tire-balance measuring apparatus - Google Patents

Abstract

PURPOSE: To provide a tire-balance measuring apparatus by which a drop in a shake and that in a shimmy can be realized simultaneously. CONSTITUTION: The rotation of a tire is detected by optical fiber sensors 10, 10'. The up-and-down vibration and the front and rear vibration of the tire are detected by accelerometers 7A, 7B, 7'A, 7'B. On the basis of values of their detection signals, the correction vector of an imbalance is operated by an analytical-device body 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire balance measuring device for measuring a tire imbalance, and more particularly to a device for measuring an unbalance of a tire mounted on a vehicle.

[0002]

2. Description of the Related Art As conventional tire balance measuring devices, there are Japanese Patent Laid-Open Nos. 62-20307 and 62-51.
There is a technique disclosed in Japanese Patent Publication No. 42-42. The former of the above-mentioned prior art is tire uniformity (mainly RF).
V) is measured and a weight that corrects the balance is attached to the opposite side of the position showing the maximum value by 180 ° to cancel the uniformity. In the latter of the above-mentioned conventional techniques, vertical vibration and longitudinal vibration of the tire are measured, and the weight balance is corrected with respect to the longitudinal vibration, and with respect to vertical vibration, the mounting position with respect to the rim of the tire is changed to correct the uniformity. It is a thing.

Generally, the longitudinal vibration of the tire is caused by an exciting force due to the imbalance of the weight of the tire, and the vertical vibration of the tire is caused by the combined force of the weight balance and the uniformity. That is, in FIG. 4, the vertical vibration unbalance vector V _V is represented by a composite vector of the longitudinal vibration unbalance vector V _H and the vibration vector V _U due to the uniformity, but in order to reduce the vector V _U due to the uniformity, When a weight equal to the magnitude of the vector V _V is attached on the opposite side of the vertical vibration unbalance vector V _V to make a modified vector V _{V ′} , the tire weight unbalance vector V _H originally exists. As a result, the tire weight imbalance vector is a composite vector V _{HV '} of the modified vector V _{V'and the} longitudinal vibration imbalance vector V _H.
It is represented by. This is the vector V by Uniformity
_Since it is a vector of equal magnitude and opposite direction to _U ,
The vector V _U due to uniformity is offset. That is, as shown in FIG. 8, the vertical vibration of the tire is reduced from b to d in FIG. Vertical vibration of the vehicle body, that is, shake, is generally a resonance phenomenon caused by a change in force due to inhomogeneity of tires. However, by correcting the vibration in the vertical direction, the vibration can be reduced from before the correction and comfortable driving is possible.

However, by adding a weight corresponding to the magnitude of the correction vector V _{V ′} , the weight unbalance composite vector V _{HV ′} becomes larger than the original weight unbalance vector V _H , and the tire The longitudinal vibration increases because the longitudinal excitation force increases. As shown in FIG. 7, shimmy, which is an automatic excitation phenomenon around the kingpin of the control wheel due to an increase in weight imbalance, that is, steering left / right vibration is corrected in the vertical direction from before correction. It increases from b to a and the driving comfort is impaired. Also to reduce the shimmy, to reduce the weight unbalance vector V _H shown in FIG. 5, adding a correction vector V _{H 'by} weight the vector V _H and size equals 180 ° opposite side, FIG. 7 As shown in FIG. 5, since the front-rear vibration of the tire is reduced, the steering shimmy is reduced to d in the same figure by the front-rear correction, and driving comfort is achieved. However, since the front and rear weight imbalances are canceled out, the vector V _U due to the uniformity remains as shown in FIG. 5, and this causes vertical vibration. That is, the vertical vibration unbalance vector V _V becomes the uniformity vector V _U , which causes an increase in tire vertical vibration. That is, as shown by a in FIG. 8, the front-back correction causes more body shake than before the correction, and the comfort is deteriorated.

[0005]

As described above, in the conventional tire balance measuring device, when the weight imbalance is corrected from the longitudinal vibration, the shimmy is decreased but the shake is increased, and the uniformity is corrected from the vertical vibration. Then, a trade-off phenomenon occurs in which the shake decreases but the shimmy increases, which is a problem. An object of the present invention is to provide a tire balance measuring device that solves the above-mentioned problems of the prior art and can achieve both shimmy reduction and shake reduction.

[0006]

Means for solving the above problems will be described with reference to a block diagram of an embodiment of the present invention. FIG. 1 is a block diagram showing the configuration and function of the present invention. In FIG. 1, the rotational state detecting means 100 has a function of detecting the rotational speed of at least one of the left and right tires mounted on the vehicle. For example, the reflective tapes 8, 8 in the embodiment shown in FIG. ′ And the optical fiber sensors 10 and 10 ′, and has a function of outputting a rotation signal and a rotation value (r.p.m.) associated with the rotation of the tire. The vertical vibration detecting means 101 and the longitudinal vibration detecting means 102 are attached to the rotation supporting portions of the left and right tires and detect the vibrations of the rotation supporting portions in the vertical and longitudinal directions. The vertical vibration detecting means 101 and the longitudinal vibration detecting means 1
Reference numeral 02 denotes, for example, the vertical acceleration sensors 7A and 7'A and the longitudinal acceleration sensor 7 in the embodiment shown in FIG.
B, 7'B. Further, the rotation power spectrum calculation means 103 calculates the power spectrum of the tire rotation signal from the rotation signal detected by the rotation state detection means 100.

First rotation primary vibration spectrum calculation means 1
Reference numeral 04 calculates the rotation frequency detected by the rotation state detecting means 100 and the power spectrum of the vertical vibration in the primary rotation of the tire from the first vibration detecting means 101.
The second rotation primary vibration spectrum calculation means 102 calculates the rotation frequency detected by the rotation state detection means 100 and the power spectrum of the front-rear vibration in the rotation primary of the tire from the second vibration detection means 102. The first phase difference calculation means 106 calculates the phase difference between the vertical vibrations from the rotation signal at the above rotation frequency and the vertical vibration signal from the first rotation primary vibration spectrum calculation means 104. The second phase difference calculation means 107 calculates the phase difference between the front and rear vibrations from the rotation signal at the rotation frequency and the front and rear vibration signals from the second rotation primary vibration spectrum calculation means 105. First
The vector calculation means 108 of the first phase difference calculation means 1
06 and the first rotational primary vibration spectrum calculation means 104 calculates the vertical unbalance vector. The second vector calculation means 109 calculates the front-back unbalance vector from the second phase difference calculation means 107 and the second rotation primary vibration spectrum calculation means 105.

The vector synthesizing means 110 synthesizes the modified vector from the first vector computing means 108 and the second vector computing means 109. Further, the first vector calculation means 108 for calculating the vertical vibration and the second vector calculation means 109 for calculating the longitudinal vibration vector combine the unbalance correction vector from the combined vector of the vertical vibration vector and the longitudinal vibration vector. . The correction vector is calculated for each of the two-point method, that is, the present condition in which no dummy weight is added and the state in which the dummy weight is added to 0 ° and 180 °. The correction vector calculation means 111 calculates the correction amount and the correction position of the vector that should correspond to the combined vector, and the correction amount and the correction position are displayed by the display means 112. Rotational power spectrum calculation means 103, first rotation primary vibration spectrum calculation means 104, second rotation primary vibration spectrum calculation means 10
5, first phase difference calculating means 106, second phase difference calculating means 107, first vector calculating means 108, second vector calculating means 109, vector synthesizing means 110, modified vector calculating means 111, display means 112 Corresponds to the part of the analysis apparatus main body 13 in the embodiment.

[0009]

FIG. 6 is a vector diagram showing a vector based on the tire vibration imbalance and uniformity of the embodiment. In the present embodiment, the longitudinal vibration unbalance vector V _H and the vertical vibration unbalance vector V _V are obtained from the tire longitudinal vibration and vertical vibration, and these two vectors V _H ,
Calculates the resultant vector V _HV of V _V, the resultant vector V
_The configuration is such that an appropriate balance amount is added so that a correction vector having a predetermined magnitude and a direction opposite to that of the _HV is formed. As shown in FIG. 6, V _HV is a combined vector of the longitudinal vibration unbalance vector V _H and the vertical vibration unbalance vector V _V , and V _S is a combined vector V _HV
And has a direction opposite to that of the correction vector having a predetermined magnitude. As a result, it is possible to reduce the weight unbalance vector V _HS after the correction and the vector (V _U −V _HS ) due to the uniformity after the correction.

[0010]

【Example】

<First Embodiment> FIGS. 2 and 3 show a reference embodiment of the present invention, FIG. 2 is a perspective view of a mechanical portion of the present embodiment, and FIG. 3 is a block diagram of the analyzer 13. In the following, the configuration in FIG. 2 mainly shows the left wheel side, but the right wheel side (the tire is not shown) is shown by adding “′”. In FIG.
The wheel 2 to which the tire 1 is attached is fastened to the hub 3 attached to the spindle 6 using bolts and nuts. The spindle 6 is connected to and supported by the strut 4 and the suspension lower arm 5. Reference numerals 7 and 7'represent acceleration sensors which are attached to the spindle 6 by adhesion or the like. The acceleration sensors 7 and 7'detect vibrations caused by the imbalance of the tire 1 and output acceleration detection signals corresponding to the detected values. To do. Although it is possible to use one sensor for each of the two axes, in FIG. 2, the vertical acceleration sensors 7A, 7'A for detecting vertical vibrations and the longitudinal acceleration sensors 7B, 7'B for detecting longitudinal vibrations are shown as left and right. Two of them are arranged at each of which the vibration detection signal corresponding to the detected value is output. Further, a reflection tape 8 is attached to the tire 1 or the wheel 2, and the reflected light from the reflection tape 8 is incident on an optical fiber sensor 10 arranged so as to face the reflection tape 8, and this optical fiber sensor An ON / OFF electric signal (rotation signal) of one pulse is output from 10 per one rotation of the wheel. Reference numerals 11A and 11'A are vertical acceleration sensor amplifiers, 11B and 11'B are longitudinal acceleration sensor amplifiers, and their output signals are input to the analyzer body 13. In addition, the optical fiber sensors 10, 10 '
The rotation signal from the optical fiber sensor amplifiers 12, 1
It is amplified by 2'and input to the analyzer body 13. A remote switch 9 composed of a plurality of switch groups and display lamps is connected to the analyzer body 13.

In FIG. 3, inside the analyzer body 13,
A microcomputer 201 for performing main operations, recording, and reading, an A / D converter 202 for A / D converting a signal input to the microcomputer 201, vertical vibration detection signals from the vertical acceleration sensors 7A, 7'A, front and rear An anti-aliasing filter 20 that cuts high-frequency components of the longitudinal vibration detection signals from the acceleration sensors 7B and 7'B and the rotation signal from the optical fiber sensors 10 and 10 '.
3, an interface circuit 204 for performing waveform shaping and the like between the remote switch 9 and the microcomputer 201, a liquid crystal display 205 for displaying calculation information and calculation results, a printer 206 and the like. Optical fiber sensors 10, 10 ', vertical acceleration sensors 7A, 7'
The signals from A and the longitudinal acceleration sensors 7B and 7'B are input to the filter 203 via the amplifiers 11 and 12, respectively, and further A / D converted by the A / D converter 202.

The remote switch 9 includes a start switch 22 for instructing the start of sampling, a cancel switch 23 for canceling sampling and calculation,
Reset switch 2 for initializing the analysis program
4. A lamp 25 and the like which are turned on at the end of the measurement are provided.

The operation of the above apparatus will be described below with reference to a two-point method in which a dummy weight is added twice (a method in which no dummy weight is added and a measurement is performed with 0 ° and 180 ° with dummy weight). To do. Figure 9
And FIG. 10 is a flowchart showing the contents of calculation in the two-point method. In this program, only the left wheel is displayed, but the right wheel is also measured and processed in the same manner. In FIG. 9, first, in order to measure the vibration state when the dummy weight is not added, when the power of the device is turned on, the start switch 22 waits for input. The start switch 22 is turned on after the vehicle is in a stable state at a predetermined vehicle speed on the chassis dynamo or roller or at a predetermined rotation speed, for example, 100 kn / h (15 Hz) or more. At present, that is, in the state without dummy weights, measurement of vibration and phase is started. First, the analog signal such as the rotation signal of the left wheel and the vertical acceleration sensor signal and the longitudinal acceleration sensor signal is converted into a digital value by the A / D converter 202, for example, every 4 msec, and the data is stored in a predetermined address of the memory. This operation is repeated until a predetermined sampling number, for example, 256 is reached. When the number of samplings reaches 256, the A / D conversion ends (steps S1 to S5). The 256 sampled rotation signal values of the left wheel are read from the memory and subjected to frequency analysis by fast Fourier transform (hereinafter referred to as FFT transform) (step S6). From the power spectrum, the frequency f of the rotation primary component is calculated. ₁ (hereinafter abbreviated as the primary rotation frequency f ₁ ) is detected (step S 7) and the rotational power spectrum value at the frequency f ₁ is obtained (step S 7).
8). Similarly, the vertical vibration signal of the left wheel is subjected to FFT conversion and the value P _V of the vertical vibration power spectrum at the primary rotation frequency f ₁
Is calculated (steps S9 to S10). Next, the phase difference θ _V between the two is calculated from the power spectrum value of the rotation signal at the primary rotation frequency f ₁ and the power spectrum value of the vertical vibration signal at the primary rotation frequency f ₁ (step S11).
Longitudinal acceleration sensor signal similarly to the FFT, the power spectrum values of a rotational primary frequency f _1, to calculate both the P _H from longitudinal vibrations power spectrum value, then the power spectrum at a rotational primary frequency f ₁ The phase difference θ _H between the two is calculated from the value and the power spectrum value at the primary vibration frequency f ₁ of the front-back vibration signal (steps S 12 to S 14). The measurement of the vibration state when the dummy weight is not added is completed by the above steps, the operator is notified of that by the lighting of the measurement end lamp, and 1 is added to the measurement counter C ₁ (steps S15 and S16). . This counter C ₁ is measured in a state where a dummy weight is not added (C ₁ = 1) or a state where the dummy weight is attached at the position of the reflection tape attached as the rotation detecting means, that is, the position of 0 ° (C
_{This is} a counter for determining whether the measurement is ₁ = 2) or the dummy weight is attached at a position on the opposite side of the reflection tape, that is, at a position of 180 ° (C ₁ = 3).

The above phase difference calculation is generally performed as follows. That is, when the rotation signal output from the optical fiber sensor is FFT-converted, one peak of the power spectrum occurs at a predetermined frequency fp at a constant rotation speed. Similarly, the result of the FFT conversion of the output of the acceleration sensor also shows the peak of the power spectrum at the predetermined frequency fp. The power spectrum value of the FFT-converted rotation signal is expressed by the following equation (1), and the power spectrum value of the vibration acceleration sensor signal is expressed by the following equation (2). The phase difference between the rotation signal and the vibration signal is θ can be calculated by the following equation (3). Fx (ω) = a + jb | Fx (ω) | = √ (a ² + b ² ) ... (Equation 1) Fy (ω) = c + jd | Fy (ω) | = √ (c ² + d ² ) (Equation 2)

[0015]

(Equation 3)

Based on these calculation formulas, the value P _V of the power spectrum of the vertical vibration at the primary rotation frequency f ₁ , the phase difference θ _V between the vertical rotation and the vertical vibration, and the primary frequency f of the rotation as described above.
The value P _H of the power spectrum of the longitudinal vibrations in _1, it is possible to obtain the phase difference theta _H rotation and longitudinal vibrations.

Returning to the flow chart, FIG. 9 to FIG.
When C ₁ = 1, the memory P _V1 , θ _V1 , P is set to each value of P _V , θ _V , P _H , and θ _H based on the measurement without adding the dummy weight. After the _values are stored in _H1 and θ _H1 , the start waiting state shown in FIG. 9 is entered (step S1).
7). Next, the position of the reflection tape attached as the rotation detecting means is set to 0 °, a dummy weight for measurement, for example, 20 grams is added to the position, the vehicle is run, and the vehicle speed is the same as when the measurement is performed without adding the dummy weight. After the vehicle speed reaches the stable state and the stable state is achieved, the start switch 22 is pushed. The same processing as when the dummy weight is not added is performed, the counter becomes C ₁ = 2, and the predetermined memory P _V0 ,
The respective values of the data P _V , θ _V , P _H , and θ _H are stored in θ _V0 , P _H0 , and θ _H0, and the state of waiting for start again is obtained (step S20). Next, a dummy weight is replaced at 180 ° on the opposite side of the reflection tape, the measurement is performed at the same vehicle speed, the counter becomes C ₁ = 3, and the predetermined memories P _V180 , θ _V180 ,
The respective values of the data P _V , θ _V , P _H , and θ _H are stored in P _H180 and θ _{H 180} (step S21). After that, when the dummy weight is not added in the state where the dummy weight is added, and when the dummy weight is added at the position of 180 ° on the opposite side of the reflection tape, the data read from each memory is used. Calculate the balance amount and unbalance vector.

FIG. 11 is a vector diagram showing an unbalance vector according to the present invention, in which no dummy weight is added: a dummy weight is added to a vector V _V 0 ° having a magnitude of P _{V and} a phase of θ _V : The size and phase of P _V0 is θ _{V0 and} the vector V _{V0 is} 180 °. The dummy weight is P _V180 and the phase is θ.
Unbalance amount of three Vector V _V180 of _V180 is calculated, V _V0
When the size of the line connecting the _ends of the vector of V _V180 and V _V180 is d, d is obtained by decomposing the above vector in the axial direction of 0 ° ← → 180 °. If the weight of the dummy weight is W, the unbalance amount U _B is expressed by the following equation (4).

[0019]

[Equation 4]

In FIG. 11, since the delay of the transmission system is omitted in FIG. 11, θ _V is in the unbalanced direction and the correction direction is on the opposite side of 180 °, that is, θ _VB = θ _V + 180 °. Subsequently, the front-rear unbalance vector V _H is also calculated by the same procedure as that of the upper-lower unbalance vector V _V (steps S21 to S23). Next, a synthetic vector V _HV obtained by synthesizing the upper and lower unbalanced vectors V _V and the front and rear unbalanced vectors V _H is obtained, and a correction having a size of approximately ½ of the size of the combined vector V _{HV is provided} on the opposite side of 180 °. Find the vector V _S. As a result, the weight imbalance vector V _H and the uniformity vector V _U can be reduced. It calculates the position to be set as the balance weight amount corresponding to the magnitude of the V _S, display 20 these results
Output using 5 and complete all measurements. The measurement operator drives the weight corresponding to the balance weight amount into a predetermined position of the tire wheel (steps S24 to S2).
7).

Table 1 below shows the magnitude of the correction vector V _S , the rate of change of the weight imbalance vector V _{H and} the rate of change of the uniformity vector V _U corresponding to the rate of change of the magnitude of the composite vector V _HV. It is a table. As is clear from Table 1, 1/2 of the size of the composite vector V _HV
At this time, the correction vector V _S has a weight imbalance vector of 0.83 and a uniformity vector of 0.56, and it can be seen that both are the smallest. For example, in FIG.
_Shows that the weight unbalance vector V _H and the uniformity vector V _U are reduced by setting the weight to 1/2 of V _HV . As a result, it is possible to solve the above-mentioned problems of the conventional technique and achieve both a decrease in shimmy and a decrease in shake.

[0022]

[Table 1]

As described above, this embodiment has means for detecting the rotational speed of the tire, vertical vibration and longitudinal vibration of the tire, and frequency analysis means, and calculates the vibration power spectrum of the primary tire rotation. A tire balance measuring device having means for calculating a phase difference, calculating an up-down unbalance vector and a front-rear unbalance vector, and performing a correction vector operation based on the vector to display a weight unbalance By reducing the vehicle body shake by reducing the steering shimmy and the uniformity vector, it is possible to reduce the vehicle body shake by making the corrections shown in Table 1 as shown in FIGS. 7 and 8. It has become possible to reduce both. Although not shown, it is also possible to calculate the combined vector by weighting the longitudinal vibration unbalance vector when the shimmy is to be reduced and the vertical vibration unbalance vector when the shake is to be reduced. Since shimmy is a problem both in terms of data and driving feeling, when trying to focus on reducing shimmy, the imbalance between front, rear, and top and bottom should be weighted to obtain a composite vector. You can That is, V * _HV = αV * _H + βV * _V (Equation 5) where α and β are weights.

<Second Embodiment> As a second embodiment, for example,
FIG. 12 shows a vector diagram when α = 1 and β = 0.5. The magnitude of the vector V _H and the vector V _V is calculated synthetic vector V _HV vector of 1/2, seeking V _HV, the size on the opposite side of the V _HV ask the same vector V _S and V _HV. In this case, the correction vector may not be 1/2 as in FIG. By adding a weight according to this V _S , the front-back unbalance vector V _HS is significantly reduced, and the uniformity vector V _U is also slightly reduced. Also, when it is desired to reduce the shake intensively, it is possible to carry out according to this. The weights α and β are, for example, provided with a potentiometer (not shown) or the like to change the voltage, input to the A / D converter 202 of the microcomputer 201 in FIG. 3, and weighted according to the A / D converted value. Is possible. Moreover, you may switch using another switch etc.

It is also possible to obtain and correct the uniformity vector from the difference between the vertical unbalance vector and the front and rear unbalance vector. That is, when the weights α and β are set to α = −1 and β = 1, the combined vector V _HV becomes V * _HV = −V * _H + V * _V (Equation 6), which is a uniformity vector V Represents _U. In this way, it is possible to correct the uniformity vector by setting the values of α and β.

Further, in the present embodiment, the dummy weight is added twice to obtain the unbalance vector. However, depending on the condition setting, the unbalance vector is calculated only from the unbalance vector when the dummy weight is not added, and the unbalance vector is simplified. Modifications are possible.

Furthermore, in place of the rotation power spectrum calculation means 102, the first-order rotation vibration spectrum calculation means 103, the phase difference calculation means 104 and the like shown in the embodiment, a means other than FFT conversion such as a band pass filter may be used. Is also possible.

<Third Embodiment> The third embodiment is an embodiment based on analog processing. In FIG. 13, reference numeral 300 denotes a rotation state detecting means for detecting the rotation state of the tire and outputting a signal of 1 pulse per one rotation, and 301 and 302 for detecting the vertical and longitudinal vibrations of the tire, and outputting a voltage signal proportional to the acceleration. The output vibration detecting means 303 and 303 ′ are bandpass filter circuits in which the cutoff frequency of the filter changes according to the output of the rotation state detecting means 300. When a rotation signal and a vibration signal are input, the tire rotation Only the vibration component of the primary frequency is extracted and a sin wave voltage signal is output. Reference numerals 304 and 304 'denote phase difference detecting circuits, which are pulse signals of the rotation state detecting means 300 and the filter circuit 30.
When the vibration signal of the primary rotation frequency of the tire that has passed 3, 303 'is input, for example, as shown in FIG. 14, the time T ₁ until the vibration waveform shows the peak value is triggered by the rising of the rotation pulse signal. When the period T ₀ of the rotation pulse signal is also counted at the same time, the phase θ becomes θ = 3
The voltage obtained by 60 ° × T ₁ / T ₀ and proportional to θ is output.

Reference numerals 305 and 305 'denote the filter circuit 30.
This circuit detects the amplitude of the signal vibration of the primary rotational frequency of the tire that has passed 3, 303 '. For example, the peak value of the vibration waveform may be detected by a circuit such as a peak hold and used as the amplitude, and a voltage proportional to the amplitude is output. 30
Reference numeral 6 denotes an arithmetic circuit, which is composed of a microcomputer, a personal computer, etc., and has a phase difference detection circuit 304,
Output from 304 'and amplitude detection circuits 305, 30
The voltage output from 5'is converted into a digital value by the A / D converter 307, the unbalance vector having the amplitude as the magnitude and the phase difference as the direction is calculated by 308 and 309, and the unbalanced vector is combined by 310 to combine. The unbalanced vector and the modified vector are calculated. It is also possible to A / D convert these and detect the amplitudes of the correction vectors 305 and 305 ′ by creating a program in the arithmetic circuit 306 and calculating it.

[0030]

According to the present invention, when the weight imbalance is corrected from the longitudinal vibration, the shimmy decreases but the shake increases. When the uniformity is corrected from the vertical vibration, the shake decreases but the shimmy increases. The problems found in the prior art have been solved, and a tire balance measuring device capable of simultaneously achieving shimmy and shake reduction can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing functions of an embodiment of the present invention.

FIG. 2 is a perspective view showing a mechanical portion of the embodiment of the present invention.

FIG. 3 is a block diagram of an analysis apparatus according to an embodiment of the present invention.

FIG. 4 is a vector diagram showing vectors of tire vibration unbalance and uniformity according to the present invention.

FIG. 5 is a vector diagram showing vectors of tire vibration unbalance and uniformity according to the present invention.

FIG. 6 is a vector diagram showing vectors of tire vibration unbalance and uniformity according to the present invention.

FIG. 7 is a characteristic diagram showing the relationship between tire rotation and steering shimmy according to the present invention.

FIG. 8 is a characteristic diagram showing the relationship between tire rotation and shake according to the present invention.

FIG. 9 is a part of a flowchart of an embodiment showing the contents of calculation of the present invention.

FIG. 10 is a part of a flowchart of an embodiment showing the content of calculation of the present invention.

FIG. 11 is a vector diagram showing an unbalance vector of the present invention.

FIG. 12 is a vector diagram showing tire vibration unbalance and uniformity vectors of the second embodiment of the present invention.

FIG. 13 is a block diagram showing functions of a third embodiment of the present invention.

FIG. 14 is a diagram showing a phase difference between a rotation signal and a vibration signal according to the third embodiment.

[Explanation of symbols]

1 ... Tire 2 ... Wheel 3 ... Hub 4 ... Strut 5 ... Suspension lower arm 7, 7 '... Acceleration sensor 7A, 7'A ... Vertical acceleration sensor 7B, 7'B ... Longitudinal acceleration sensor 8, 8' ... Reflective tape 9 ... Remote switch 10, 10 '... Optical fiber sensor 11, 11' ...
Amplifier 12, 12 '... Optical fiber sensor amplifier 13 ...
Analysis device main body 22 ... Start switch 23 ...
Cancel switch 24 ... Reset switch 25 ...
Lamp 100 ... Rotational state detecting means 101 ... Vertical vibration detecting means 102 ... Longitudinal vibration detecting means 103 ... Rotational power spectrum calculation means 104 ... First rotation primary spectrum calculation means 105 ... First rotation primary spectrum calculation means 106 ... 1st phase difference calculating means 107 ... 2nd phase difference calculating means 108 ... 1st vector calculating means 109 ... 2nd vector calculating means 110 ... Vector combining means 111 ... Correction vector calculating means 112 ... Display means 201 ... Micro Computer 202 ... A
/ D converter 203 ... Anti-aliasing filter 204 ... Interface circuit 205 ... Liquid crystal display 206 ... Printer 300 ... Rotation state detecting means 301 ... Vertical vibration detecting means 302 ... Front-rear vibration detecting means 303, 303 '... Frequency variable bandpass filter 304 , 304 '... Phase difference detection circuit 305, 30
5 '... Amplitude detection circuit 306 ... Microcomputer 307 ... A
/ D conversion circuit 308 ... Upper / lower unbalance arithmetic circuit 309 ... Front / rear unbalance arithmetic circuit 310 ... Composite vector arithmetic circuit S1 to S27 ... Processing steps

Claims (5)

[Claims] 1. A rotation state detecting means for detecting a rotation signal of at least one of left and right tires mounted on a vehicle, and a rotation power spectrum calculating means for outputting a rotation signal representing a primary rotation state from the rotation signal. A first vibration detecting means which is attached to a rotation supporting member of the tire for detecting the rotation state, detects a vertical vibration state of the tire, and outputs a vertical vibration signal representing the state; and detects the rotation state. Second vibration detecting means attached to the rotation supporting member of the tire for detecting the longitudinal vibration state of the tire and outputting a longitudinal vibration signal representing the state, based on the rotation signal and the vertical vibration signal. A first rotation primary spectrum calculation means for outputting a vertical vibration signal in the first rotation, and a first rotation spectrum based on the rotation signal and the front-back vibration signal. Second rotation primary spectrum calculation means for outputting a longitudinal vibration signal, a rotation signal indicating the rotation primary state detected by the rotation state detection means, and the first rotation primary spectrum calculation means. The first phase difference calculating means for calculating the phase difference based on the vertical vibration signal in the first rotation, the rotation signal indicating the first rotation state detected by the rotation state detecting means, and the second rotation 1 Second phase difference calculating means for calculating a phase difference based on the longitudinal vibration signal in the first rotation detected by the next spectrum calculating means, the phase difference calculated by the first phase difference calculating means, and the first phase difference calculating means. First vector calculation means for calculating a vertical unbalance vector based on the vibration level of the vertical vibration signal detected by the rotation primary spectrum calculation means of Second vector calculation means for calculating the front-rear unbalance vector based on the phase difference calculated by the second phase difference calculation means and the vibration level of the front-rear vibration signal detected by the second rotation primary spectrum calculation means. A vector synthesizing means for synthesizing the upper and lower unbalanced vectors and the front and rear unbalanced vectors, and a correction vector computing means for computing a correction amount and a correction position of a vector that should correspond to the synthesized vector. Tire balance measuring device. 2. The tire balance measuring device according to claim 1, wherein the unbalance vector synthesizing means has an additional arithmetic function for performing arithmetic operation by weighting the upper and lower unbalance vectors or the front and rear unbalance vectors respectively. 3. The uniformity vector is calculated from the difference between the upper and lower unbalance vectors calculated by the first vector calculation means and the front and rear imbalance vectors calculated by the second vector calculation means. The tire balance measuring device according to claim 1, further comprising means for calculating 4. The tire balance measuring device according to claim 1, wherein each of the arithmetic processes is based on an arithmetic value by an unbalance vector in a state where no dummy weight is added. 5. A rotational state detecting means for detecting a rotational signal of at least one of left and right tires mounted on a vehicle, and a vertical vibration state of the tire mounted on a rotation supporting member of the tire for detecting the rotational state. Is attached to the rotation supporting member of the tire for detecting the rotation state, the first vibration detecting means for outputting a vertical vibration signal indicating the state, and detecting the vibration state in the front-rear direction of the tire, Rotation of the tire 1 by inputting the second vibration detecting means for outputting the longitudinal vibration signal indicating the state, the rotation signal from the rotation state detecting means, and the vibration signals from the first and second vibration detecting means. A variable frequency filter circuit that outputs a vibration signal of a next frequency; and a circuit that detects the amplitude of the vibration signal of the primary rotation frequency of the tire from the variable frequency filter circuit. A circuit that detects the phase difference between the rotation signal and the vibration signal from the rotation signal and the output of the frequency variable filter circuit, and an output from the circuit that detects the amplitude and the circuit that detects the phase difference is A / D converted. And a circuit for performing the calculation of a vertical unbalance vector, a front-rear unbalance vector, and a combined vector thereof, the tire balance measuring device.