Method for balancing a wheel tire assembly

Abstract

The present invention relates to a method for balancing a wheel-tire assembly. The method may include: measuring a position of a maximum value of a radial force variation (RFV) of a tire, and marking the measured maximum value position as a tire reference position; measuring each of an internal runout and an external runout of the wheel; extracting a principal component of a waveform of the measured internal runout and a principal component of a waveform of the measured external runout, and respectively setting the previously and subsequently measured principal components as an internal runout waveform and an external runout waveform; synthesizing the internal runout waveform and the external runout waveform, and marking a position of a minimum value of a synthesized waveform obtained by the synthesis as a wheel reference position; aligning the tire reference position on the tire and the wheel reference position on the wheel to have the same phase, and assembling the wheel and the tire.

Description

Technical Field

[0001] The present invention relates to a technique for balancing a wheel-tire assembly. Background Art

[0002] A wheel equipped with a tire is rotatably coupled to a vehicle and thus rotates when the vehicle is in motion. The balance of the wheel assembly is crucial for the smooth and quiet running of the vehicle.

[0003] Ideally, the tire and the wheel can be manufactured to have circumferentially uniform characteristics in terms of precision. However, in practice, the manufactured products have a slight degree of imbalance between the tire and the wheel.

[0004] The information included in this background art section is only intended to enhance the overall understanding of the background of the present invention and should not be regarded as an admission or any form of implication that this information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] Aspects of the present invention aim to provide a method for balancing a wheel-tire assembly, which is configured to provide a more appropriate balance between the tire and the wheel, thereby reducing vibrations of the vehicle body and slight wobbling of the steering wheel when the vehicle is in motion. The method provides the advantage of improving the riding comfort of the vehicle.

[0006] According to aspects of the present invention, there is provided a method for balancing a wheel-tire assembly, the method comprising: measuring the position of the maximum value of the radial force variation (RFV) of the tire, and marking the measured maximum value position on the tire as the tire reference position; measuring each of the internal runout and the external runout of the wheel; extracting the main components of the waveform of the measured internal runout and the main components of the waveform of the measured external runout, and setting the previously measured main component and the subsequently measured main component as the internal runout waveform and the external runout waveform, respectively; synthesizing the internal runout waveform and the external runout waveform, and marking the position of the minimum value of the synthesized waveform obtained by the synthesis on the wheel as the wheel reference position; aligning the tire reference position on the tire and the wheel reference position on the wheel to have the same phase, and assembling the wheel and the tire.

[0007] In the method, the position of the maximum value of the RFV of the tire may be set as the position of the maximum value of the main component of the RFV.

[0008] In the method, when synthesizing the internal runout waveform and the external runout waveform of the wheel, the internal runout waveform and the external runout waveform may be superimposed, and only the contour portions having relatively larger values or the same values may be connected to form a synthesized waveform.

[0009] In the method, when superimposing the internal runout waveform and the external runout waveform, with both ends of one cycle portion of the internal runout waveform set to be respectively the same as both ends of one cycle portion of the external runout waveform, one cycle portion of the internal runout waveform having the same phase can be superimposed on one cycle portion of the external runout waveform.

[0010] According to various aspects of the present invention, there is provided a method for balancing a wheel-tire assembly, the method comprising: measuring each of the internal runout and the external runout of the wheel; extracting an internal runout waveform represented as a continuous function from data obtained by measuring the internal runout of the wheel; extracting an external runout waveform represented as a continuous function from data obtained by measuring the external runout of the wheel; synthesizing the internal runout waveform and the external runout waveform to generate a synthesized waveform; marking the position of the minimum value of the synthesized waveform on the wheel as the wheel reference position; measuring the RFV of the tire; extracting a waveform of the tire represented as a continuous function from data obtained by measuring the RFV of the tire; marking the position of the maximum value of the waveform of the tire on the tire as the tire reference position; and assembling the wheel and the tire in a state where the wheel reference position on the wheel and the tire reference position on the tire are aligned with the same phase.

[0011] In the method, when extracting the internal runout waveform from data obtained by measuring the internal runout of the wheel, the data obtained by measuring the internal runout of the wheel can be subjected to Fourier transform, the main component of the data after Fourier transform can be extracted, and the extracted main component can be set as the internal runout waveform.

[0012] In the method, when extracting the external runout waveform from data obtained by measuring the external runout of the wheel, the data obtained by measuring the external runout of the wheel can be subjected to Fourier transform, the main component of the data after Fourier transform can be extracted, and the extracted main component can be set as the external runout waveform.

[0013] In the method, when synthesizing the internal runout waveform and the external runout waveform to generate a synthesized waveform, with both ends of one cycle portion of the internal runout waveform set to be respectively the same as both ends of one cycle portion of the external runout waveform, one cycle portion of the internal runout waveform having the same phase is superimposed on one cycle portion of the external runout waveform, and only the portions having relatively larger positive amplitudes or the same positive amplitudes in the superimposed waveforms can be connected to generate the synthesized waveform.

[0014] According to another aspect of the present invention, there is provided a method of marking the minimum value position of the runout of a wheel, the method comprising: measuring each of the internal runout and the external runout of the wheel; extracting the principal components of the waveform of the measured internal runout and the principal components of the waveform of the measured external runout, and setting the previously and subsequently measured principal components as the internal runout waveform and the external runout waveform, respectively; forming a composite waveform by superposing the internal runout waveform of the wheel and the external runout waveform and connecting only the contour portions having relatively larger values or the same values; and marking the minimum value position of the composite waveform as the minimum value position of the runout of the wheel.

[0015] In the method, with the two ends of one cycle portion of the internal runout waveform set to be the same as the two ends of one cycle portion of the external runout waveform, respectively, the composite waveform can be formed by superposing one cycle portion of the internal runout waveform and one cycle portion of the external runout waveform.

[0016] According to another aspect of the present invention, there is provided an apparatus for marking the minimum value position of the runout of a wheel, the apparatus comprising: a measuring unit that measures each of the internal runout and the external runout of the wheel; a waveform extraction unit that extracts the principal components of the waveform of the measured internal runout and the principal components of the waveform of the measured external runout, and sets the previously and subsequently measured principal components as the internal runout waveform and the external runout waveform, respectively; a waveform synthesis unit that forms a composite waveform by superposing the internal runout waveform of the wheel and the external runout waveform and connecting only the contour portions having relatively larger values or the same values; and a marking unit that marks the minimum value position of the composite waveform as the minimum value position of the runout of the wheel.

[0017] In the apparatus, the waveform extraction unit may be configured to set the principal component obtained by performing a Fourier transform on the waveform of the measured internal runout as the internal runout waveform, and set the principal component obtained by performing a Fourier transform on the waveform of the measured external runout as the external runout waveform.

[0018] In the apparatus, the waveform synthesis unit may be configured to: with the two ends of one cycle portion of the internal runout waveform set to be the same as the two ends of one cycle portion of the external runout waveform, respectively, form a composite waveform by superposing one cycle portion of the internal runout waveform and one cycle portion of the external runout waveform.

[0019] According to various exemplary embodiments of the present invention, a more appropriate balance between the tire and the wheel is provided, thereby reducing vibrations of the vehicle body, slight shaking of the steering wheel, etc. when the vehicle is running. This provides the advantage of improving the riding comfort of the vehicle.

[0020] The methods and apparatuses of the present invention have other features and advantages that will be apparent from, or will be set forth in detail in, the accompanying drawings and the subsequent embodiments incorporated herein, which together are used to explain specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A flowchart showing a method for balancing a wheel-tire assembly according to various exemplary embodiments of the present invention;

[0022] Figure 2 A schematic diagram showing a method for balancing a wheel-tire assembly according to various exemplary embodiments of the present invention;

[0023] Figures 3A, 3B, 3C, and 3D are graphs showing the formation of a composite waveform using the internal runout waveform and the external runout waveform of a wheel according to various exemplary embodiments of the present invention;

[0024] Figure 4 A schematic diagram showing a method for determining the minimum runout position of a wheel using only the external runout waveform of the wheel;

[0025] Figure 5 A schematic diagram showing a method for determining the minimum runout position of a wheel using only the internal runout waveform of the wheel;

[0026] Figure 6 A schematic diagram showing a method for determining the minimum runout position of a wheel using the average value of the internal runout waveform and the external runout waveform of the wheel;

[0027] Figure 7 A schematic diagram showing a method for determining the minimum runout position of a wheel using a composite waveform obtained by synthesizing the internal runout waveform and the external runout waveform of the wheel according to various exemplary embodiments of the present invention;

[0028] Figure 8 A flowchart showing a method for marking the minimum runout position of a wheel according to various exemplary embodiments of the present invention; and

[0029] Figure 9 A schematic diagram showing the configuration of an apparatus for marking the minimum runout position of a wheel according to various exemplary embodiments of the present invention.

[0030] It should be understood that the accompanying drawings are not necessarily drawn to scale, but rather present a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features included in the present invention (including, for example, specific dimensions, orientations, positions, and shapes) will be determined in part by the particular environment in which it is to be applied and used.

[0031] In these figures, throughout the several views of the drawings, like reference numerals denote the same or equivalent parts of the present invention. Detailed Description of the Invention

[0032] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the invention will be described in conjunction with the exemplary embodiments of the present invention, it should be understood that this specification is not intended to limit the invention to those exemplary embodiments. On the contrary, the invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative forms, modifications, equivalents, and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0033] Reference Figure 1 and Figure 2 , a method for balancing a wheel-tire assembly according to various exemplary embodiments of the present invention includes: step S10, step 20, step 30, step 40, and step 50; step S10 measures the position of the maximum value of the radial force variation (RFV) of the tire T, and marks the measured maximum value position on the tire T as the tire reference position P1; step S20 measures each of the internal runout and the external runout of the wheel W; step S30 extracts the principal components of the waveform of the measured internal runout and the principal components of the waveform of the measured external runout, and sets the previously and subsequently measured principal components as the internal runout waveform and the external runout waveform, respectively; step S40 synthesizes the internal runout waveform and the external runout waveform, and marks the position of the minimum value of the synthesized waveform obtained by the synthesis on the wheel W as the wheel reference position P2; step S50 aligns the tire reference position P1 on the tire T with the wheel reference position P2 on the wheel W to have the same phase, and assembles the wheel W and the tire T.

[0034] That is, according to various exemplary embodiments of the present invention, the position of the maximum value of the RFV of the tire T is measured, and the measured position is marked as the tire reference position P1. In addition, the position of the minimum value obtained from the composite waveform obtained by combining the internal runout waveform and the external runout waveform of the wheel W is marked as the wheel reference position (P2). Therefore, the wheel W and the tire T are assembled in a state where the tire reference position P1 and the wheel reference position P2 are aligned with the same phase. As a result, the amplitude of the RFV of the wheel-tire assembly is significantly reduced.

[0035] Of course, as described above, in a state where the amplitude of the RFV of the wheel-tire assembly is reduced, when the wheel-tire assembly is installed on a vehicle, the body vibration or the slight shaking of the steering wheel W caused by the dynamic imbalance of the wheel-tire assembly during vehicle driving is reduced or avoided, thereby greatly improving the vehicle ride comfort.

[0036] As a reference, according to various exemplary embodiments of the present invention, the runout of the wheel represents the runout in the radial direction of the wheel (i.e., in its radial direction).

[0037] The position of the maximum value of the RFV of the tire T is set as the position of the maximum value of the main component of the RFV.

[0038] That is, while the tire T to be assembled rotates in the measuring device, the RFV is measured. The waveform of the measured RFV is subjected to Fourier transform to obtain the position of the maximum value of the main component. The obtained position is the tire reference position P1.

[0039] Of course, the position of the maximum value of the measured RFV waveform itself can be set as the tire reference position P1 without performing Fourier transform on the RFV waveform (measured in the measuring device). However, in this case, it is difficult to exclude the possibility of erroneously selecting the substantial maximum value position of the RFV due to noise. As described above, according to various exemplary embodiments of the present invention, the position of the maximum value of the main component is selected by performing Fourier transform. Therefore, the substantial maximum value position of the RFV of the tire T can be correctly selected without obvious error.

[0040] On the other hand, as described above, each of the internal runout and the external runout of the wheel W is measured, and the corresponding main components of the measured internal runout and external runout waveforms are extracted by performing Fourier transform on their waveforms. Therefore, the main component of the measured internal runout waveform is set as the internal runout waveform, and the main component of the measured external runout waveform is set as the external runout waveform.

[0041] For the synthesis of the internal runout waveform and the external runout waveform of the wheel W, the internal runout waveform and the external runout waveform are superimposed. Therefore, only the profile portions having relatively high values or the same values are connected to form a synthesized waveform.

[0042] That is, in a state where both ends of a one-cycle portion of the internal runout waveform and both ends of a one-cycle portion of the external runout waveform are respectively the same, a one-cycle portion of the internal runout waveform and a one-cycle portion of the external runout waveform having the same phase are superimposed. Therefore, in these superimposed waveforms, only the profile portions having relatively large amplitudes or the same amplitudes are connected to form a synthesized waveform.

[0043] For example, referring to FIGS. 3A and 3B, when both ends of a part (i.e., a one-cycle portion) within the range of 0° to 360° of the internal runout waveform WI of the wheel are set to be respectively the same as both ends of a part (i.e., a one-cycle portion) within the range of 0° to 360° of the external runout waveform WO of the wheel and a one-cycle portion of the internal runout waveform WI and a one-cycle portion of the external runout waveform WO are superimposed, as shown in FIG. 3C, the two waveforms WI and WO are superimposed. In this state, as shown in FIG. 3D, the profile portions having relatively large positive amplitudes or the same positive amplitudes are connected to form a synthesized waveform WT.

[0044] At this time, B1 and B2 are the minimum value positions of the synthesized waveform and ultimately become the final positions of the minimum points of the runout of the wheel determined according to each exemplary embodiment of the present invention. When marked on the wheel, any one of these two positions becomes the position P2 of the minimum point in the wheel.

[0045] Reference Figure 4 、 Figure 5 、 Figure 6 and Figure 7 describe a method for determining the minimum value position of the runout of the wheel W and marking the minimum value position.

[0046] Figure 4 FIG. is a schematic diagram showing Logic 1, which is a method for determining the minimum value position of the runout of the wheel W using only the external runout waveform of the wheel W. Four cases obtained by combining the internal runout of the wheel W and the external runout of the wheel W are classified as Samples 1 to 4. A method for selecting the final minimum value position of the runout in each of Samples 1 to 4 is described.

[0047] Sample 1 is a state where the amplitude of the internal runout of the wheel W is less than 0.05, so there is almost no runout on the inner side of the wheel, and the amplitude of the external runout of the wheel W is 0.15 to 0.3, so there is a relatively large degree of runout on the outer side of the wheel.

[0048] In Logic 1, only the external runout waveform WO of the wheel is used to determine the minimum position of the runout of the wheel. Therefore, the position marked as A, which represents the minimum position of the external runout waveform (WO) of the wheel, is determined as the final minimum position of the runout of the wheel W. However, at the position of the internal runout waveform (WI) of the wheel that is generally represented by point A, the maximum degree of runout occurs. Therefore, point A is not suitable for representing the minimum position of the runout of the wheel W.

[0049] Conversely, as described below for comparison, the minimum positions of the runout of the wheel obtained from the composite waveform WT according to various exemplary embodiments of the present invention are determined as B1 and B2. As described above, considering that at point A, the external runout of the wheel is minimum and the internal runout of the wheel is maximum, it should be understood that B1 and B2 are more suitable for replacing A to represent the minimum position of the runout of the wheel.

[0050] For reference, in Figure 4 、 Figure 5 and Figure 6 , the minimum positions of the runout of the wheel obtained from the composite waveform according to various exemplary embodiments of the present invention are represented as "optimal solutions".

[0051] As described above, when Logic 1 is applied to Sample 1, A is located between B1 and B2, so a position relatively close to B1 or B2 is selected as the minimum point of the runout of the wheel. Therefore, the evaluation result is that a point close to the substantially minimum position is located.

[0052] In Sample 2, the amplitude of the internal runout of the wheel W is in a relatively large range of 0.15 to 0.3, and the maximum value of the external runout of the wheel W is less than 0.05. This is the opposite of the situation in Sample 1.

[0053] When Logic 1 is applied to Sample 2, for the inner side of the wheel W where the runout has substantially changed to a large extent, the runout is not even reflected, and the minimum position A of the external runout waveform WO of the wheel is selected as the minimum position of the runout of the wheel. Therefore, as shown in the figure, the evaluation result is that a suitable minimum position of the runout of the wheel is not located.

[0054] In Sample 3, in a state where the internal runout waveform and the external runout waveform are in the same phase, the corresponding amplitudes of the internal runout and the external runout of the wheel W are in a relatively large range of 0.15 to 0.3. When Logic 1 is applied to Sample 3, the minimum position of the external runout waveform WO of the wheel is the same as the minimum position of the internal runout waveform WI of the wheel. Therefore, as shown in the figure, the evaluation result is that the minimum position is correctly located.

[0055] In Sample 4, in a state where the internal runout waveform and the external runout waveform are in opposite phases, the corresponding amplitudes of the internal runout and the external runout of the wheel W are in a relatively large range of 0.15 to 0.3. The minimum value position of the internal runout waveform WI of the wheel is located on the left side. However, the minimum value position A of the external runout waveform WO of the wheel is located on the right side. Therefore, A, which is the minimum value position of the external runout waveform WO of the wheel, is not suitable as the minimum value position representing the runout of the entire wheel. The evaluation result is that in Sample 4, the minimum value position on the wheel is not located by applying Logic 1.

[0056] In contrast, Figure 4 Logic 2 is shown, which is a method of determining the minimum value position of the runout of the wheel W by using only the internal runout waveform WI of the wheel. Figure 5

[0057] As shown in the figure, when Logic 2 is applied to Sample 2, the evaluation result is that a point close to the minimum value position is located. When Logic 2 is applied to Sample 3, the evaluation result is that the minimum value position is located. However, when Logic 2 is applied to Sample 1 and Sample 4, the evaluation result is that a representative minimum value position on the wheel W is not located.

[0058] Figure 6 Logic 3 is shown, which is a method of determining the minimum value position of the runout of the wheel W by using the average waveform WA, which is the average of the internal runout waveform WI of the wheel and the external runout waveform WO of the wheel.

[0059] Different from Logic 1 or Logic 2, in Logic 3, the minimum value position of the runout of the wheel is located by considering the internal runout waveform WI and the external runout waveform WO of the wheel. As shown in the figure, the minimum value position of the average waveform WA (formed by connecting the corresponding average values of the amplitudes of the internal runout waveform WI and the external runout waveform WO) is determined as the minimum value position of the runout of the wheel.

[0060] When Logic 3 is applied to Samples 1 to 4, as shown in the figure, in Samples 1, 2, and 3, the minimum value position of the runout of the wheel W or a position close to its minimum value position is located. However, in Sample 4, the same form of runout waveforms are arranged in opposite phases. Therefore, the average waveform WA almost forms a horizontal line. Thus, the minimum value position of the runout of the wheel cannot be specified.

[0061] Figure 7 A summary of how to select the minimum value position of the runout of the wheel W in Samples 1 to 4 according to various exemplary embodiments of the present invention is shown. From Figure 7 ​As can be seen, in each of Samples 1 to 4, the representative minimum value position of the runout of the wheel W is located.

[0062] As a reference, according to various exemplary embodiments of the present invention, in the case where the minimum value position of the runout of the wheel is located, in each of Samples 1, 2, and 4 except for Sample 3, two minimum value positions of the runout of the wheel are selected. In fact, only one of them is marked on the wheel.

[0063] Of course, as described above, the RFV of the wheel-tire assembly can be minimized. That is, the substantially representative minimum value position of the runout of the wheel W is located, and then this position is marked as the wheel reference position (P2) using a point or the like. Therefore, the wheel and the tire are assembled in a state where the tire reference position P1 of the tire T and the wheel reference position P2 of the wheel W are aligned in the same phase.

[0064] A method for balancing a wheel-tire assembly according to various exemplary embodiments of the present invention is provided.

[0065] That is, referring to Figure 1 , the method according to various exemplary embodiments of the present invention includes: Step S20, in which each of the internal runout and the external runout of the wheel is measured; Step S31, in which an internal runout waveform drawn as a continuous function is extracted from the data obtained by measuring the internal runout of the wheel; Step S32, in which an external runout waveform drawn as a continuous function is extracted from the data obtained by measuring the external runout of the wheel; Step S41, in which the internal runout waveform and the external runout waveform are synthesized to generate a synthesized waveform; Step S42, in which the minimum value position of the synthesized waveform is marked on the wheel as the wheel reference position; Step S11, in which the RFV of the tire is measured; Step S12, in which a waveform of the tire drawn as a continuous function is extracted from the data obtained by measuring the RFV of the tire; Step S13, in which the maximum value position of the waveform of the tire is marked on the tire as the tire reference position; Step S50, in which the wheel and the tire are assembled in a state where the wheel reference position on the wheel and the tire reference position on the tire are aligned in the same phase.

[0066] In Step S31 of extracting the internal runout waveform from the data obtained by measuring the internal runout of the wheel, a Fourier transform is performed on the data obtained from the internal runout of the wheel, the main component of the data after the Fourier transform is extracted, and the extracted main component is set as the internal runout waveform WI.

[0067] In addition, in step S32 of extracting the external runout waveform from the data obtained by measuring the external runout of the wheel, Fourier transform is performed on the data obtained from the external runout of the wheel, the main component of the data after Fourier transform is extracted, and the extracted main component is set as the external runout waveform WO.

[0068] In step S41 of generating the composite waveform WT, in a state where one cycle portion of the internal runout waveform WI and one cycle portion of the external runout waveform WO are aligned to have the same phase, both ends of one cycle portion of the internal runout waveform WI are set to be the same as both ends of one cycle portion of the external runout waveform WO, respectively. Therefore, only the portions having relatively large positive amplitudes or the same positive amplitudes in the superimposed waveforms are connected to form the composite waveform WT.

[0069] On the other hand, a method of marking the minimum value position of the runout of the wheel will be described only separately below. As Figure 8 shown, the method includes step S20, step S30, step S41, and step S42; step S20 measures each of the internal runout and the external runout of the wheel W; step S30 extracts the main components of the waveforms of the measured internal runout and the measured external runout, and sets the previously measured main component and the subsequently measured main component as the internal runout waveform and the external runout waveform, respectively; step S41 superimposes the internal runout waveform of the wheel W and the external runout waveform, thereby forming a composite waveform by connecting only the profile portions having relatively large values or the same values; step S42 marks the minimum value position of the composite waveform as the minimum value position of the runout of the wheel W.

[0070] That is, the minimum value position of the runout of the wheel is the same as the wheel reference position.

[0071] Of course, in a state where both ends of one cycle portion of the internal runout waveform are set to be the same as both ends of one cycle portion of the external runout waveform, respectively, a composite waveform is formed by superimposing one cycle portion of the internal runout waveform having the same phase and one cycle portion of the external runout waveform.

[0072] Figure 9Schematic diagram showing the configuration of a device for marking the minimum value position of the runout of a marked wheel according to various exemplary embodiments of the present invention. The device includes a measurement unit 1, a waveform extraction unit 3, a waveform synthesis unit 5, and a marking unit 7; the measurement unit 1 measures each of the internal runout and the external runout of the wheel; the waveform extraction unit 3 extracts the main components of the measured waveform of the internal runout and the main components of the measured waveform of the external runout, and sets the previously measured and subsequently measured main components as the internal runout waveform and the external runout waveform respectively; the waveform synthesis unit 5 superimposes the internal runout waveform and the external runout waveform of the wheel, thereby forming a synthesized waveform by only connecting the contour portions having relatively larger values or the same values; the marking unit 7 marks the minimum value position of the synthesized waveform as the minimum value position of the runout of the wheel.

[0073] Of course, a measuring device for measuring the RFV of the tire can be provided separately. The marking device can also be configured to additionally measure the RFV of the tire.

[0074] The waveform extraction unit 3 is configured to: set the main component obtained by performing Fourier transform on the measured waveform of the internal runout as the internal runout waveform, and set the main component obtained by performing Fourier transform on the measured waveform of the external runout as the external runout waveform.

[0075] The waveform synthesis unit 5 is configured to: superimpose a one-period portion of the internal runout waveform and a one-period portion of the external runout waveform having the same phase in a state where both ends of a one-period portion of the internal runout waveform are set to be the same as both ends of a one-period portion of the external runout waveform respectively, thereby generating a synthesized waveform.

[0076] In various exemplary embodiments of the present invention, the controller can execute the method of the present invention such as Figure 1 and Figure 8 The controller can include the measurement unit 1, the waveform extraction unit 3, the waveform synthesis unit 5, and the marking unit 7 disclosed in Figure 9 .

[0077] Additionally, the term "controller" or "control unit" refers to a hardware device that includes a memory and a processor configured to execute one or more steps understood as algorithmic structures. The memory stores the algorithmic steps, and the processor executes the algorithmic steps to perform one or more processes of the method according to various exemplary embodiments of the present invention. The controller according to an exemplary embodiment of the present invention can be implemented by a non-volatile memory configured to store an algorithm for controlling the operation of various components of a vehicle or data on software instructions for executing the algorithm, and a processor configured to perform the above operations using the data stored in the memory. The memory and the processor can be separate chips. Alternatively, the memory and the processor can be integrated in a single chip. The processor can be implemented as one or more processors.

[0078] The controller or control unit can be at least one microprocessor operated by a predetermined program, and the predetermined program can include a series of instructions for performing the method according to various exemplary embodiments of the present invention.

[0079] The foregoing invention can also be implemented as computer-readable code on a computer-readable recording medium. A computer-readable recording medium is any data storage device capable of storing data that can subsequently be read by a computer system. Examples of computer-readable recording media include hard disk drives (HDDs), solid state drives (SSDs), silicon disk drives (SDDs), read-only memories (ROMs), random access memories (RAMs), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, etc., and are implemented as carrier waves (e.g., transmitted via the Internet).

[0080] For ease of explanation and precise definition of the appended claims, the terms "above", "below", "inside", "outside", "upper", "lower", "upward", "downward", "front", "rear", "back", "inward", "outward", "inner", "outer", "internal", "external", "inner side", "outer side", "forward", "backward" are used to describe the features of the exemplary specific embodiments with reference to the positions of these features shown in the drawings. It should be further understood that the term "connected" or its derivatives denote both direct connection and indirect connection.

[0081] The foregoing description of specific exemplary embodiments of the invention has been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive nor to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain particular principles of the invention and its practical application so as to enable others skilled in the art to implement and utilize the invention in various exemplary embodiments and with various alternatives and modifications. The scope of the invention is intended to be defined by the appended claims and their equivalents.

Claims

1. A method for balancing a wheel-tire assembly, the method comprising: Measuring the position of the maximum value of the radial force variation of the tire, and marking the measured maximum value position on the tire as the tire reference position; Measuring each of the internal runout and the external runout of the wheel; Extracting the main components of the waveform of the measured internal runout and the main components of the waveform of the measured external runout, and setting them as the internal runout waveform and the external runout waveform respectively; Combining the internal runout waveform and the external runout waveform, and marking the position of the minimum value of the combined waveform obtained by combination on the wheel as the wheel reference position; Aligning the tire reference position on the tire and the wheel reference position on the wheel to have the same phase, and assembling the wheel and the tire; Wherein, when combining the internal runout waveform and the external runout waveform of the wheel, the internal runout waveform and the external runout waveform are superimposed, and only the contour parts with relatively larger values or the same values are connected to form a combined waveform.

2. The method according to claim 1, wherein The position of the maximum value of the radial force variation of the tire is set as the position of the maximum value of the main component of the radial force variation.

3. The method according to claim 1, wherein When superimposing the internal runout waveform and the external runout waveform, with both ends of one cycle part of the internal runout waveform set to be the same as both ends of one cycle part of the external runout waveform respectively, one cycle part of the internal runout waveform with the same phase is superimposed on one cycle part of the external runout waveform.

4. A method for balancing a wheel-tire assembly, the method comprising: Measuring each of the internal runout and the external runout of the wheel; Extracting an internal runout waveform represented as a continuous function from the data obtained by measuring the internal runout of the wheel; Extracting an external runout waveform represented as a continuous function from the data obtained by measuring the external runout of the wheel; Combining the internal runout waveform and the external runout waveform to generate a combined waveform; Marking the position of the minimum value of the combined waveform on the wheel as the wheel reference position; Measuring the radial force variation of the tire; Extracting a waveform of the tire represented as a continuous function from the data obtained by measuring the radial force variation of the tire; Marking the position of the maximum value of the waveform of the tire on the tire as the tire reference position; Assembling the wheel and the tire in a state where the wheel reference position on the wheel and the tire reference position on the tire are aligned to have the same phase; Wherein, when combining the internal runout waveform and the external runout waveform to generate a combined waveform, with both ends of one cycle part of the internal runout waveform set to be the same as both ends of one cycle part of the external runout waveform respectively, one cycle part of the internal runout waveform with the same phase is superimposed on one cycle part of the external runout waveform, and only the parts with relatively larger positive amplitudes or the same positive amplitudes in the superimposed waveform are connected to generate a combined waveform.

5. The method according to claim 4, wherein When extracting the internal runout waveform from the data obtained by measuring the internal runout of the wheel, performing a Fourier transform on the data obtained by measuring the internal runout of the wheel, extracting the main components of the data after Fourier transform, and setting the extracted main components as the internal runout waveform.

6. The method according to claim 4, wherein When extracting an external runout waveform from data obtained by measuring the external runout of a wheel, perform a Fourier transform on the data obtained by measuring the external runout of the wheel, extract the principal components of the data after the Fourier transform, and set the extracted principal components as the external runout waveform.

7. A method of marking the minimum value position of the runout of a wheel, the method comprising: measuring each of the internal runout and the external runout of the wheel; extracting the principal components of the waveform of the measured internal runout and the principal components of the waveform of the measured external runout, and setting them as the waveform of the internal runout and the waveform of the external runout, respectively; forming a composite waveform by superimposing the internal runout waveform of the wheel on the external runout waveform and connecting only the contour portions having relatively large values or the same values; marking the minimum value position of the composite waveform as the minimum value position of the runout of the wheel.

8. The method according to claim 7, wherein Form a composite waveform by superimposing one cycle portion of the internal runout waveform on one cycle portion of the external runout waveform with both ends of one cycle portion of the internal runout waveform set to be the same as both ends of one cycle portion of the external runout waveform, respectively.

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