JP5017919B2 - Inspection apparatus and inspection method - Google Patents

Description

  The present invention relates to an inspection technique for inspecting an assembled state of a tire and a wheel.

  In the vehicle, if the assembled state of the tire and the wheel is not appropriate, the vehicle may vibrate when the vehicle travels, or the straightness of the vehicle may deteriorate. For this reason, inspection of the assembly state of the tire and the wheel is performed as one of the quality control of the vehicle. As such a tire inspection method, there is a method in which an operator visually determines. However, visual judgment varies depending on individual differences among workers, and uniform quality control is difficult.

Further, as a tire inspection method, a tire having a wheel assembled using a tire uniformity tester is rotated while being applied to the roller of the tester, and the load cell attached to the roller is used to rotate the X axis, the Y axis, Measures the force component in the Z-axis direction, calculates the measured values of RFV (up-and-down load fluctuation component), LFV (left-right lateral force fluctuation component), and LFD (right-and-left lateral force straight component), and checks assembly It is also possible to perform. However, this inspection method takes time to calculate the measurement result, and it is difficult to use it for inspecting all the assembled states of tires and wheels on the vehicle production line. Further, a technique for automating tire inspection as in Patent Document 1 has been proposed. The device described in Patent Document 1 measures the radial outer shape of the side surface of the tire over the entire circumference of the tire while rotating the tire and the wheel assembled to each other around the rotation axis, and the measurement result The assembly state is determined based on the above.
Japanese Patent No. 3677245

  However, the technique disclosed in Patent Document 1 measures the amount of shake or the like at one location in the vicinity of the rim to determine the assembled state, and the inspection accuracy is not necessarily high. Further, there may be a problem with the tire or the wheel itself, and there may be a case where such a problem cannot be found only by inspecting a certain amount of deflection in the vicinity of the rim.

  Accordingly, an object of the present invention is to inspect the assembled state of a tire and a wheel with higher accuracy and in a short time.

According to the present invention, in the inspection apparatus for inspecting the assembled state of the tire and the wheel, the rotating means for rotating the tire and the wheel assembled to each other around the rotation axis thereof, and the tire rotated by the rotating means Measuring means for measuring the outer shape in the radial direction of the side surface over the entire circumference of the tire, and an amount of deflection for calculating the amount of deflection at a plurality of radial positions on the side surface of the tire based on the measurement result of the measuring means A plurality of types of evaluation means for evaluating an assembly state of the tire and the wheel based on a plurality of the shake amounts selected from the shake amounts of the plurality of portions calculated by the calculation means and the shake amount calculation means and an evaluation value calculation means for calculating an evaluation value, the plurality of types of evaluation value is an evaluation factor affecting the vibration of the vehicle, on the time of rotation of the tire and the wheel Of the tire and the wheel, which is an evaluation element that affects the vibration of the vehicle, the vibration of the vehicle and the straightness, the left and right vibration during rotation of the tire and the wheel, and the straightness of the vehicle. There is provided an inspection apparatus characterized in that it is a value indicating the center position of left and right shake during rotation .

  In this inspection apparatus, the evaluation value is calculated based on the plurality of shake amounts selected from the shake amounts of the plurality of portions calculated by the shake amount calculation unit. By setting the parameter for determining the evaluation value as the amount of shake at a plurality of locations, the inspection accuracy can be improved, and it is possible to inspect defects of the tire and the wheel themselves, and the inspection can be performed in a short time. Furthermore, the evaluation value calculation means calculates a plurality of types of evaluation values, so that the assembled state of the tire and the wheel can be evaluated in a multifaceted manner.

Moreover, according to this structure, the influence which the assembly | attachment state of a tire and a wheel has on the driving | running | working performance of a vehicle can be evaluated in many ways .

  In the present invention, the evaluation value calculation means is determined in advance according to the type of the evaluation value, and the maximum runout amount of a specific part selected from the plurality of parts, or the side surface of the tire It is possible to employ a configuration in which the evaluation value is calculated based on at least one of the integral values of the maximum shake amount in a certain range in the radial direction. According to this configuration, it is possible to more appropriately calculate a plurality of types of evaluation values. Further, the evaluation value can be calculated more appropriately by introducing an integral value of the maximum runout amount in a certain range in the radial direction of the side surface of the tire in accordance with the evaluation value.

In the present invention, the shake amount calculated by the shake amount calculation unit may include a lateral shake amount along the rotational axis direction and a vertical shake amount along the radial direction. . According to this configuration, the assembled state of the tire and the wheel can be evaluated from multiple aspects .

Also, according to the present invention, in the inspection method for inspecting the assembled state of the tire and the wheel, while rotating the tire and wheel are assembled together in the rotary axis, the radial direction of the side surface of the tire A measuring step for measuring the outer shape over the entire circumference of the tire, a deflection amount calculating step for calculating a deflection amount in a plurality of portions in the radial direction of the side surface of the tire based on the measurement result of the measuring step, and A plurality of types of evaluation values for evaluating an assembly state of the tire and the wheel are calculated based on the plurality of shake amounts selected from the shake amounts of the plurality of portions calculated by the shake amount calculation step. and an evaluation value calculating step, the plurality of types of evaluation value is an evaluation factor affecting the vibration of the vehicle, deflection of the upper and lower during rotation of the tire and the wheel, straight and vibration of the vehicle The center position of the left and right runout during rotation of the tire and the wheel, and the center position of the left and right runout during rotation of the tire and the wheel, which is an evaluation element that affects the straight traveling performance of the vehicle. An inspection method is provided that is a value indicating This inspection method can achieve the same effect as the above-described inspection apparatus.

  As described above, according to the present invention, the assembled state of the tire and the wheel can be inspected with higher accuracy and in a short time.

<Device configuration>
1 is a block diagram of an inspection apparatus 10 according to an embodiment of the present invention. The inspection device 10 is a device that inspects the assembled state of the tire T and the wheel W, and the rotation device 20 that rotates the tire T and the wheel W that are assembled to each other around the rotation axis, and the rotation device 20 rotates the rotation device 20. A measuring device 30 that measures the outer shape of the side surface of the tire T in the radial direction (r) over the entire circumference of the tire T and a computer 40 are provided.

  The rotating device 20 includes a spindle 21 that rotates about a vertical direction (Z), a motor 22 that is a drive source of the spindle 21, and a support portion 23 that is provided at the upper end of the spindle 21. The support portion 23 is fitted into the center mounting hole of the wheel W so that the side surface of the tire T is horizontal. The rotating device 20 also includes a support portion 24, which is concentric with the support portion 23 and is provided so as to be moved up and down by an unillustrated lifting mechanism and is fitted into a mounting hole of the wheel W from above. Accordingly, the rotating device 20 positions the wheel W and the tire T by the support portions 23 and 24, and rotates the tire T and the wheel W in the horizontal posture around the vertical direction (Z) by the rotation of the spindle 21. The rotating device 20 further includes a rotation sensor 25 such as a rotary encoder. The rotation sensor 25 is a sensor for detecting the rotation angle of the tire T and the wheel W. In this embodiment, the rotation sensor 25 detects the rotation angle of the output shaft of the motor 22.

  In the case of this embodiment, the measuring device 30 is located at a position facing the front side and the back side of the tire T in order to measure the outer shape in the radial direction (r) of the front side (upper side) side surface and the back side (lower side) side surface of the tire T. A total of two are provided. In the present embodiment, the measurement device 30 includes a laser light irradiation unit 31 and an imaging unit 32. The irradiation unit 31 is arranged at a predetermined distance from the side surface of the tire T in the vertical direction (Z), and irradiates slit light along the radial direction (r) of the tire T perpendicular to the side surface of the tire T. The imaging unit 32 includes a CCD sensor and an optical system, and images the slit light irradiation area on the side surface of the tire T. The photographed image 30a shows the outline (outer shape) of the outer peripheral portion of the radial cross-sectional shape of the side surface of the tire T. In addition to this, as the measuring device 30, for example, a device that scans a laser distance meter in the radial direction of the tire T can also be employed.

  The measuring device 30 shoots the outer shape of the side surface of the tire T according to the rotation angle of the tire T and the wheel W, and shoots the entire circumference of the tire T in units of 10 degrees, for example. When the image is taken in units of 10 degrees, 36 images are obtained. These images are converted into data representing the outer shape in the radial direction (r) of the side surface of the tire T in two-dimensional coordinates (Zr plane). FIG. 2 is data in which the outer shape of the side surface of the tire T in the radial direction (r) is expressed in two-dimensional coordinates, and the data at each rotation angle of the tire T and the wheel W are displayed in an overlapping manner. The width of the data line in FIG. 2 represents the runout of the side surface of the tire T.

  Returning to FIG. 1, the computer 40 executes a later-described inspection process CPU 41, a RAM 42 that stores temporary data and the like, a ROM 43 that stores fixed data and programs, and a later-described inspection process program. And a hard disk drive (HDD) 44 for storing data, which is a measurement result of the measuring device 30, in the hard disk. The RAM 42, ROM 43, and HDD 44 may be other types of storage means.

  The interface (I / F) 45 a is an input / output interface for exchanging data between the drive circuit (not shown) of the motor 22, the rotation sensor 25, and the measurement device 30 and the CPU 41. The I / F 45b is an input interface for exchanging data between the operation unit 46, which is an input device such as a keyboard and a mouse, and the CPU 41. The operation unit 46 is a unit for the user to instruct execution of inspection processing, which will be described later, and various settings. The I / F 45c is an output interface for exchanging data between the display 47 and the CPU 41. The display 47 is a display device that displays inspection results and the like.

<Outline of inspection>
In the present embodiment, based on the measurement result of the measurement device 30, first, the shake amount at a plurality of portions in the radial direction (r) of the side surface of the tire T is calculated. Next, a plurality of types of evaluation values for evaluating the assembled state of the tire T and the wheel W are calculated based on the plurality of shake amounts selected from the calculated shake amounts of the plurality of parts. And the quality of an assembly state is determined according to the evaluation value.

  FIG. 3A is an explanatory diagram of evaluation values in the present embodiment. In the present embodiment, three types of evaluation values are used: Y1 related to vertical deflection during rotation of the tire T when the tire T is mounted on the vehicle, Y2 related to horizontal deflection, and Y3 related to the center of horizontal deflection. The evaluation value Y1 is an evaluation element that affects the vibration of the vehicle. The evaluation value Y2 is an evaluation factor that affects the vibration and straightness of the vehicle. The evaluation value Y3 is an evaluation factor that affects the straight traveling performance of the vehicle. The evaluation value Y3 focuses on the fact that the vehicle is skewed if the center of the left and right deflection of the tire T is deviated from the center of the left and right of the tire T. The evaluation values Y1, Y2, and Y3 are the differences between the RFV, LFV, and LFD values of the tire T alone and the RFV, LFV, and LFD values when the tire T and the wheel W are assembled, that is, RFV, LFV, This corresponds to the amount of change in LFD.

In the case of the present embodiment, the equations for calculating these evaluation values Y1 to Y3 are obtained by regression analysis, and are correlated with the above-described changes in RFV, LFV, and LFD. In the present embodiment, the multiple regression equation used for the regression analysis uses the following equation with the evaluation values Y1 to Y3 as dependent variables.
Evaluation value _{Y = a 1 · A 1 +} ··· + a k · A k + b 1 · B 1 + ··· + b m · B m + c 1 · C 1 + ··· + c n · C n + D
Here, a, b, and c are regression coefficients, and D is a constant. A, B, and C are independent variables and are as follows.

  FIG. 3B is an explanatory diagram of the independent variables A to C. In the figure, the maximum value and the minimum value are the maximum value and minimum value of the measurement result of the measuring device 20 (maximum value and minimum value in the vertical direction (Z) at an arbitrary position in the radial direction (r) of the side surface of the tire T). It is. The independent variable A is the maximum runout amount (vertical runout amount) along the radial direction (r) in a specific portion of the side surface of the tire T in the radial direction (r). This is the maximum amount of deflection in the direction. The independent variable B is the maximum runout amount (lateral runout amount) along the rotation axis direction (Z direction) of the tire T at a specific portion in the radial direction (r) of the side surface of the tire T. It is the maximum amount of shake in the left-right direction at that part. The independent variable C is an integral value of the maximum shake amount in a certain range in the radial direction (r) of the side surface of the tire T, that is, an integral value of the lateral shake amount. In addition, the regression coefficient and the subscript of the independent variable in the above formula are numbers specifying each part in the radial direction (r) of the side surface of the tire T.

  The regression coefficients a to c are calculated in advance by experiments. In the experiment, for example, dozens of good and defective products of the same type of tire T and wheel W assembled with each other are prepared as samples. For example, a defective product is intentionally produced by biting a foreign object between the tire T and the wheel W and improperly assembled. A plurality of types of foreign matters having different thicknesses are prepared, and a plurality of types of defective products are created.

  For each of several tens of samples, the outer shape in the radial direction (r) of the side surface of the tire T is measured by the inspection device 10 or a device of the same type, and the above-described uniformity tester is used to measure the sample. The values of RFV, LFV, and LFD when the tire T and the wheel W are assembled are measured. From the measurement results of the outer shape, the independent variables A to C are calculated, and for each of the evaluation values Y1 to Y3, the values of the RFV, LFV, and LFD of the tire T alone and the above-described assembled state are added to the multiple regression equation. Differences from the measured values of RFV, LFV, and LFD, that is, changes in RFV, LFV, and LFD are substituted for Y, and independent variables A to C are substituted. Regression coefficients a to c are calculated from the substituted multiple regression equation by the least square method or the like. In addition, the terms of independent variables that have little influence on the evaluation values Y1 to Y3 are deleted. In the multiple regression equation, the difference between the RFV, LFV, and LFD values of the tire T alone and the measured values of RFV, LFV, and LFD in the assembled state, that is, the amount of change in RFV, LFV, and LFD By substituting each for Y, the accuracy (validity) of the multiple regression equation in the assembled state of the tire T and the wheel W can be increased.

Thus, a regression coefficient is obtained for each evaluation value Y1 to Y3, and a multiple regression equation is obtained. In an experiment conducted by the inventor of the present invention, a multiple regression equation for a tire and a wheel was obtained as follows, for example. In addition, the content of the independent variable of the following formula | equation is shown to Fig.4 (a) and (b). 4A shows the outer shape of the front side surface of the tire T, and FIG. 4B shows the outer shape of the rear side surface of the tire T.
Evaluation value: Y1 = c ₁₁ · C ₁ + c ₁₂ · C ₂ + D ₁ (Formula 1)
Evaluation _{value: Y2 = c 21 · C 1} + c 22 · C 2 -b 21 · B 1 + b 22 · B 2 + D 2 ( Equation 2)
Evaluation _{value: Y3 = c 31 · C 2} + c 32 · C 3 -a 1 · A 1 + D 3 ( Equation 3)
The width of the side surface of the sample tire T (the width seen in the assembled state) is about 7 cm, and the independent variable A1 is the vertical runout amount in the vicinity of the wheel W on the front side surface of the tire T. The independent variable B1 is a lateral runout amount of a portion of the front side surface of the tire T that is about 5 cm from the wheel W. The independent variable B <b> 2 is a lateral runout amount of a portion of the tire T on the back side surface of the wheel W about 4 cm from the wheel W. The independent variables C1 to C3 are integral values of the lateral runout amount of the front side surface of the tire T, and the lateral runout in the range of about 1 cm to 1.5 cm, about 1.5 cm to 2 cm, and about 4 cm to 4.5 cm from the wheel W in order. This is the integral value of the quantity.

Although the specific value of each regression coefficient is not shown in particular, it has the following relationship.
c ₁₁ > c ₁₂
b ₂₂ > b ₂₁ > c ₂₁ > c ₂₂
a ₁ > c ₃₁ > c ₃₂
D ₁ , D ₂ , and D ₃ are constants calculated by regression analysis. The multiple regression equations having the regression coefficients thus determined are stored in the HDD 44 in advance.

<Inspection process>
Next, an inspection procedure by the inspection apparatus 10 will be described using the above formulas 1 to 3. FIG. 5 is a flowchart of the inspection process executed by the CPU 41. When the tire T and the wheel W assembled to each other are set in the rotating device 20, the CPU 41 executes the process of FIG. In S1, the rotating device 20 is operated to rotate the tire T and the wheel W at a constant speed. In S2, with reference to the detection result of the rotation sensor 25, it is determined whether the rotation angle of the tire T and the wheel W is a measurement angle. If applicable, the process proceeds to S3, and if not applicable, the process waits.

  In S <b> 3, the outer shape of the tire T in the radial direction (r) is measured by the measuring device 30. In S4, the measurement data is stored in the HDD 44. In S5, it is determined whether or not the measurement device 30 has measured the entire circumference of the tire T. If applicable, the process proceeds to S6, and if not, the process returns to S2. In S6, the rotation of the tire T and the wheel W by the rotating device 20 is stopped.

  In S7, based on the measurement data stored in S4, the amount of deflection at a plurality of portions in the radial direction (r) of the side surface of the tire T is calculated. The amount of deflection is only required for determining the independent variables used in the above equations 1 to 3. In S8, the shake amount is selected according to the evaluation values Y1 to Y3 from the shake amounts of the plurality of parts calculated in S7, and the independent variables A1, B1, B2, C1 to C3 are set and stored in the HDD 44. The evaluation values Y1 to Y3 are calculated by substituting this into the above equations 1 to 3.

  In S9, whether the assembled state is good or bad is determined. Here, if the evaluation values Y1 and Y2 exceed the preset threshold values, the product is determined to be defective, and if the evaluation value Y3 is equal to or less than the threshold value, it is determined to be a non-defective product. If it is outside the threshold value, it is determined as a defective product. In S10, the determination result of S9 is displayed on the display 47. The determination result can be displayed for each evaluation value Y1 to Y3. The inspector determines whether or not to use the tire T and the wheel W by looking at the evaluation result.

  As described above, in the inspection apparatus 10 according to the present embodiment, the inspection accuracy is improved by setting the parameters (independent variables) for determining the evaluation values Y1 to Y3 as the amounts of deflection of a plurality of portions in the radial direction (r) of the tire T. Can do. Further, by looking at the amount of shake at a plurality of locations, not only a simple assembly error can be found, but also defects in the tire T and the wheel W themselves can be inspected. Furthermore, the assembly state of the tire T and the wheel W can be evaluated in a multifaceted manner by calculating a plurality of types of evaluation values Y1 to Y3. In addition, the inspection can be performed in a short time compared to the uniformity testing machine, and 100% inspection can be performed.

  Further, as a parameter (independent variable) for determining the evaluation values Y1 to Y3, an evaluation value that is an integrated value of the maximum shake amount in a certain range in the radial direction (r) in addition to the maximum shake amount (vertical shake amount and lateral shake amount). The evaluation values Y1 to Y3 can be calculated more appropriately by finding parameters correlated with the values and using these in accordance with the types of the evaluation values Y1 to Y3.

  Further, by using the vertical runout amount and the lateral runout amount as parameters (independent variables) for determining the evaluation values Y1 to Y3, a set of the tire T and the wheel W such as the center of the top and bottom, left and right runout, and left and right runout of the tire T is used. The attached state can be evaluated from multiple aspects.

  Further, in the present invention, as the evaluation values Y1 to Y3, the vertical deflection (Y1), the horizontal deflection (Y2), and the central position (Y3) of the horizontal deflection when the tire T and the wheel W are rotated are adopted. Thus, it is possible to evaluate the influence of the assembled state of the tire and the wheel on the running performance of the vehicle from various aspects.

1 is a block diagram of an inspection apparatus 10 according to an embodiment of the present invention. This is data representing the outer shape in the radial direction of the side surface of the tire T in two-dimensional coordinates. (A) is explanatory drawing of evaluation value Y1 thru | or Y3, (b) is explanatory drawing of an independent variable. (A) And (b) is explanatory drawing of an independent variable. It is a flowchart which shows the example of the process which CPU41 of the test | inspection apparatus 10 performs.

DESCRIPTION OF SYMBOLS 10 Inspection apparatus 20 Rotating apparatus 30 Measuring apparatus T Tire W Wheel

Claims (4)

In an inspection device that inspects the assembled state of a tire and a wheel,
Rotating means for rotating the tire and the wheel assembled to each other around the rotation axis;
Measuring means for measuring a radial outer shape of a side surface of the tire rotated by the rotating means over the entire circumference of the tire;
Based on the measurement result of the measuring means, a shake amount calculating means for calculating a shake amount in a plurality of portions in the radial direction of the side surface of the tire;
Based on a plurality of the shake amounts selected from the shake amounts of the plurality of parts calculated by the shake amount calculation means, a plurality of types of evaluation values for evaluating an assembly state of the tire and the wheel are calculated. Evaluation value calculating means for
Equipped with a,
The plurality of types of evaluation values are evaluation elements that affect the vibration of the vehicle, and the tires and the evaluation points that affect the vertical vibration of the tire and the wheel, the vibration of the vehicle, and the straightness. Inspection device characterized in that it is a value indicating a center position of left and right runout during rotation of the tire and the wheel, which is an evaluation factor that affects left and right runout during rotation of the wheel and straightness of the vehicle . The evaluation value calculation means includes
Predetermined according to the type of the evaluation value, the maximum runout amount of a specific portion selected from the plurality of portions, or the maximum runout amount in a certain radial range of the side surface of the tire The inspection apparatus according to claim 1, wherein the evaluation value is calculated based on at least one of integral values.   The shake amount calculated by the shake amount calculation means includes a lateral shake amount along the rotation axis direction and a vertical shake amount along the radial direction. The inspection device described. In the inspection method for inspecting the assembly state of tires and wheels,
A measurement step of measuring the outer shape in the radial direction of the side surface of the tire over the entire circumference of the tire while rotating the tire and the wheel assembled with each other around the rotation axis;
Based on the measurement result of the measurement step, a shake amount calculation step for calculating a shake amount in a plurality of portions in the radial direction of the side surface of the tire,
Based on a plurality of the shake amounts selected from the shake amounts of the plurality of parts calculated in the shake amount calculation step, a plurality of types of evaluation values for evaluating an assembly state of the tire and the wheel are calculated. An evaluation value calculation step to perform,
Equipped with a,
The plurality of types of evaluation values are evaluation elements that affect the vibration of the vehicle, and the tires and the evaluation points that affect the vertical vibration of the tire and the wheel, the vibration of the vehicle, and the straightness. Inspection method characterized in that it is a value indicating a center position of left and right runout during rotation of the tire and the wheel, which is an evaluation factor that affects left and right runout during rotation of the wheel and straightness of the vehicle .

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