JP5487331B1 - Master tire assembly, basic data creation method using the same, and calibration method for uniformity measuring device - Google Patents

Abstract

An object of the present invention is to provide a calibration technique for a uniformity measuring apparatus according to the absolute evaluation method.
A master tire assembly including an inner ring, an outer ring, and a tire portion corresponds to a calibration original. Since the inner diameter ring 20 and the outer diameter ring 40 are obtained by machining a metal, the dimensional accuracy is good.
The master tire assembly 10 can be used to calibrate the uniformity measuring apparatus. Since absolute evaluation is possible with the master tire assembly 10, the present invention provides a calibration technique for a uniformity measuring apparatus according to the absolute evaluation method.
[Selection] Figure 5

Description

  The present invention relates to a calibration technique for an apparatus that measures a uniformity (whether or not a fluctuation in force falls within a threshold) inherent in a tire assembly in which a wheel is assembled to a tire.

For example, in an automobile manufacturing factory, wheels are assembled to tires on a line different from the body assembly line. The resulting assembly is called a “tire assembly” (see FIG. 14). The tire assembly is supplied to a vehicle body assembly line, where it is assembled to the vehicle body.
Uniformity tests have been carried out even in units of tire assemblies to assure quality, and various uniformity measuring apparatuses have been put to practical use (see, for example, Patent Document 1 (FIG. 2)). .

The uniformity test is also defined in JIS D 4233 (automatic tire uniformity test method), and in this test, radial force variation (RFV), lateral force variation (LFV), and the like are measured.
RFV is defined as the fluctuation value (maximum value) of the radial force generated while a tire receiving a load makes one rotation at a certain radius, and LFV is a constant value of a tire receiving a load. It is defined as a fluctuation value (maximum value) of a lateral force generated during one rotation with a radius.

  On the second page, upper left column, lines 9 to 15 of Patent Document 1, “In a tire uniformity machine, a test piece having a known quantity (for example, a kg original) is different from a general measuring device. Even if it exists, it is impossible to check the performance of the whole measuring device based on it because the FV value (FORCE VARIATION: the magnitude of the force in the radial direction (kg)) is completely known. This is because there is no tire. "

  Therefore, in Patent Document 1, for example, 10 tires are repeatedly measured 10 times in order to acquire a total of 100 data, and the uniformity machine is appropriate depending on whether or not the standard deviation is within a specified range. It is determined whether or not. This method is called a 10 × 10 (Tenbaiten) test and is widely adopted.

This 10 × 10 (Tenbaiten) test requires a lot of time and labor for measurement.
Further, since this is merely a relative evaluation method using actual tires and only the reproducibility of data is observed, the reliability is remarkably reduced as compared with absolute evaluation.

  Therefore, it has been desired that the uniformity machine be managed and maintained not by relative evaluation but by absolute evaluation.

JP-A 64-66536

  An object of the present invention is to provide a technique for calibrating a uniformity measuring apparatus according to the absolute evaluation method.

The invention according to claim 1 includes an inner diameter ring, an outer diameter ring attached to the outer peripheral surface of the inner diameter ring, and a tire portion attached to the outer peripheral surface of the outer diameter ring, and is used for calibration of the uniformity measuring apparatus. A master tire assembly,
The inner ring is
A disc portion having an axle insertion hole and a hub bolt insertion hole;
A cylindrical portion extending along the axle from above and below the periphery of the disc portion when the disc portion is held horizontally;
A plurality of upper first female screw portions and lower first female screw portions that are provided on each of the upper and lower end faces of the cylindrical portion and into which a first bolt extending along the axle is screwed;
A plurality of upper second bolt holes and lower second bolt holes which are provided in the cylindrical portion at the upper and lower sides of the disk portion and extend perpendicularly to the axle and through which the second bolts are inserted;
A plurality of upper third female threads and lower third female threads provided in the cylindrical portion above the upper second bolt hole or below the lower second bolt hole and extending so as to be orthogonal to the axle and screwed in the third bolt. Consists of
The outer diameter ring is
It consists of a left upper split ring, an upper right split ring, a lower left split ring and a lower right split ring which are divided into two parts on the horizontal line after dividing the cylinder into two parts,
Each of these split rings
A split tube portion extending along an outer peripheral surface of the inner ring and having a second female screw portion into which the second bolt is screwed;
An inner flange portion having a first bolt hole extending from one end of the divided cylindrical portion so as to cover the end surface of the cylindrical portion and having the first bolt inserted therethrough;
An outer flange portion extending outward from the outer periphery of the inner flange portion;
It consists of a center side flange portion extending outward from the other end of the divided cylinder portion,
The tire portion is a solid rubber body integrally formed on an outer peripheral surface of the outer diameter ring after being attached to the inner diameter ring.

The invention according to claim 2 is a preparation step of preparing the master tire assembly according to claim 1 and a uniformity measuring device for measuring the uniformity of the tire assembly for practical use;
Using the first to third bolts, a rounding step for making the master tire assembly a perfect circle so that the inner peripheral surface of the outer diameter ring is in close contact with the outer peripheral surface of the inner diameter ring;
A first measurement step of measuring a maximum value of a radial force variation and a maximum value of a lateral force variation of the master tire assembly that has been rounded by the uniformity measuring device;
A zero point adjusting step of adjusting a load cell mounted on the uniformity measuring apparatus so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the first measuring step are zero; ,
A first non-circular circle that uses the first to third bolts to create a gap between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring to make the master tire assembly non-circular. Conversion process,
Using the uniformity measuring device adjusted by the zero point adjustment step, the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the non-circular master tire assembly are measured. A second measuring step,
Second measurement for storing the shape of the master tire assembly in the first non-rounding step and the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the second measuring step. Data storage process;
Using the first to third bolts, a gap is formed between the outer peripheral surface of the inner diameter ring and the inner peripheral surface of the outer diameter ring. A second non-rounding step for making a non-round shape with a shape different from the shape;
Using the uniformity measuring device adjusted by the zero point adjustment step, the maximum value of the radial force variation and the lateral direction of the master tire assembly non-rounded by the second non-rounding step A third measuring step for measuring the maximum value of force fluctuation;
The third measurement for storing the shape of the master tire assembly in the second non-rounding step and the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the third measuring step. Data storage process,
At least two types of basic data are stored in the second measurement data storage step and the third measurement data storage step.

The invention according to claim 3 is a uniformity measuring apparatus for calibrating a uniformity measuring apparatus that requires calibration using the basic data created by the basic data creating method using the master tire assembly according to claim 2. The calibration method of
A first pre-calibration measurement step of measuring the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the rounded master tire assembly by the uniformity measuring device that requires calibration; ,
The load cell mounted on the uniformity measuring apparatus that requires the calibration is adjusted so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the measurement process before the first calibration become zero. Zero point adjustment process before calibration,
Based on the information stored in the second measurement data storage step, a master preparation step of preparing a master tire assembly having the same form as that in the first non-rounding step,
Before the second calibration, the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the master tire assembly prepared in the master preparation step are measured using a uniformity measuring device that requires calibration. Measuring process;
Comparing the maximum value obtained in the second pre-calibration measurement process with the maximum value stored in the second measurement data storage process, and calibrating the load cell so that both maximum values match,
Zero point adjustment and at least one calibration are performed.

  In the invention according to claim 1, the master tire assembly is constituted by a tire portion including an inner ring, an outer ring, and a solid rubber body. The inner and outer rings are machined to ensure dimensional accuracy. If it is a hollow tire, uneven thickness will inevitably occur, but since it is a solid rubber body in the present invention, uneven thickness does not occur. Therefore, the master tire assembly of the present invention has extremely good dimensional accuracy.

  Furthermore, since the tire portion can be elastically deformed, various types of non-circular master tire assemblies can be created by making the outer diameter ring non-circular using the first to third bolts. In other words, a single master tire assembly can be used to create a perfect master tire assembly and many types of non-circular master tire assemblies, greatly increasing the manufacturing and storage costs of the master tire assembly. Can be reduced.

In the invention which concerns on Claim 2, a zero point adjustment process is implemented by using a perfect circle master tire assembly, and the zero point of a uniformity measuring apparatus is adjusted. This zero point adjustment increases the measurement accuracy of the uniformity measuring device. With this uniformity measuring device with increased measurement accuracy, basic data for calibration to be performed at a later date is acquired, so the reliability of the basic data is also increased.
That is, according to the present invention, highly reliable basic data for calibration can be acquired using the uniformity measuring apparatus to be calibrated later and the master tire assembly prepared in claim 1. Since it is not necessary to prepare special equipment or equipment, the cost for implementation can be reduced.

  In the invention according to claim 3, the zero point adjustment and at least one calibration are performed on the uniformity measuring apparatus to be calibrated. This calibration is based on absolute evaluation. That is, according to the present invention, unlike the conventional relative evaluation, there is provided a technique for calibrating the uniformity measuring apparatus according to the absolute evaluation method.

1 is a perspective view of a master tire assembly according to the present invention. It is an exploded view of an inner diameter ring and an outer diameter ring. It is sectional drawing of an inner diameter ring and an outer diameter ring. It is a figure explaining the formation method of a tire part. It is sectional drawing of a master tire assembly. It is a top view of a master tire assembly. It is sectional drawing of the master tire assembly made non-circular. It is sectional drawing of another master tire assembly made non-circular. It is a side view of a uniformity measuring device. It is a graph of the RFV fluctuation value before zero point adjustment. It is a graph of the RFV fluctuation value after zero point adjustment. It is a graph of the RFV fluctuation value in the non-rounded master tire assembly. It is a graph of the RFV fluctuation value in another master tire assembly made non-circular. It is sectional drawing of a tire assembly. It is a graph explaining the procedure of the zero point adjustment performed to the uniformity measuring apparatus which requires calibration. It is a graph of the RFV fluctuation value after a secular change. It is a graph of another RFV fluctuation value after a secular change. It is sectional drawing of the master tire assembly different from FIG. It is a perspective view which shows the example of a change of a master tire assembly. It is a perspective view which shows the further example of a change of a master tire assembly.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

As shown in FIG. 1, the master tire assembly 10 includes an inner diameter ring 20, an outer diameter ring 40, and a tire portion 60.
A combination of the inner diameter ring 20 and the outer diameter ring 40 corresponds to a normal wheel. The tire portion 60 corresponds to a normal wheel tire.

  The “tire assembly” is defined as an assembly in which a wheel is incorporated in a tire. “Master” means a standard or standard. Therefore, the master tire assembly 10 corresponds to a specific member used for calibration, that is, a calibration master, unlike a tire assembly (see FIG. 14) that is put to practical use.

  As shown in FIG. 2, the inner diameter ring 20 is one, but the outer diameter ring 40 includes an upper left split ring 41, an upper right split ring 42, a lower left split ring 43, and a lower right split ring 44. Note that the left and right and the top and bottom are names for convenience, and the top and bottom may be read as left and right.

  As shown in FIG. 3, the inner diameter ring 20 includes a disk-shaped disc portion 24 having a thick boss portion 21 in the center and an axle insertion hole 22 and a hub bolt insertion hole 23, Downwardly, a cylindrical portion 26 extending along the axle 25 indicated by the center line, and a plurality of upper portions into which first bolts 27 provided along the axle 25 are provided on each of the upper and lower end surfaces 26a, 26b of the cylindrical portion 26 are screwed. The first female threaded portion 28 and the lower first female threaded portion 29, and a plurality of upper portions that are provided on the cylindrical portion 26 at positions above and below the disk portion 24 and extend perpendicularly to the axle 25 and through which the second bolt 31 is inserted. A second bolt hole 32 and a lower second bolt hole 33 are provided in the cylindrical portion 26 above the upper second bolt hole 32 or below the lower second bolt hole 33 and extend so as to be orthogonal to the axle 25. Bolt 3 It comprises a plurality of on the third female threaded portion 35 及下 third female threaded portion 36. which is screwed.

Further, as described above, the outer diameter ring 40 includes the upper left split ring 41, the upper right split ring 42, the lower left split ring 43, and the lower right split ring 44 which are divided into two parts vertically by dividing the cylinder into two.
Each of the split rings 41 to 44 extends along the outer peripheral surface 37 of the inner ring 20 and has a split cylinder part 46 having a second female thread part 45 into which the second bolt 31 is screwed, and one end of the split cylinder part 46. An inner flange portion 48 that extends so as to cover the end face 26 a or 26 b of the cylindrical portion 26 and has a first bolt hole 47 through which the first bolt 27 is inserted, and an outer flange portion that extends outward from the outer periphery of the inner flange portion 48. 49 and a center side flange portion 51 extending outward from the other end (the end portion close to the disc portion 24) of the divided cylindrical portion 46. The first bolt hole 47 is a long hole that extends to the left and right of the drawing (along the radiation extending from the axle 25).

Next, a specific example of how to make the tire portion 60 will be described.
As shown in FIG. 4, the outer diameter ring 40 is set on the inner diameter ring 20 so that the outer diameter ring 40 is in close contact with the inner diameter ring 20.
These are set in the lower mold 61. Then, the lower outer flange portions 49, 49 come into contact with the lower mold 61. Next, the upper mold 62 is put on. Then, the upper outer flange portions 49, 49 come into contact with the upper mold 62. In addition, since the cylindrical support 63 that fits into the axle insertion hole 22 stands on the lower mold 61, the inner diameter ring 20 is positioned with respect to the lower mold 61. Thus, an annular cavity 67 is formed.

  Next, the liquid rubber 65 is injected from the injection port 64. The liquid rubber 65 is preferably NBR (nitrile butadiene rubber) which is a kind of synthetic rubber. Since air escapes from the exhaust port 66, the liquid rubber 65 is smoothly filled in the cavity 67. When the liquid rubber 65 is solidified and exceeds a predetermined strength, the upper mold 62 is removed and the molded product is removed from the lower mold 61.

That is, as shown in FIG. 5, the master tire assembly 10 including the inner diameter ring 20, the outer diameter ring 40, and the tire portion 60 is obtained.
Since the inner diameter ring 20 and the outer diameter ring 40 are obtained by machining a metal, the dimensional accuracy is good. As described with reference to FIG. 4, since the tire part 60 is integrally formed on the outer diameter ring 40 by the lower mold 61 and the upper mold 62, the dimensional accuracy of the tire part 60 is also good.
Furthermore, since the tire part 60 is a solid rubber body, there is no fear of uneven thickness unlike a hollow rubber body.

  Therefore, as shown in FIG. 6, the outer shape of the master tire assembly 10 is a perfect circle. In addition, the outer shape of the master tire assembly 10 is made into a non-circular shape (an ellipse, an ellipse, or other distorted circle) using the first to third bolts 27, 31 (see FIG. 5), 34. Can do. The procedure will be described next.

For example, in FIG. 7A, the first bolt 27 is sufficiently loosened. The second bolt 31 is loosened by a (dimension a; the same applies hereinafter). Next, the third bolt 34 is tightened by a. Next, the first bolt 27 is sufficiently tightened. As a result, gaps a and a are provided between the inner diameter ring 20 and the outer diameter ring 40. Since the tire part 60 is an elastic body and has a large deformability, the formation of a gap between a and a is not hindered.
Thus, one form of master tire assembly 10B is completed.

  That is, as shown in FIG. 7B, the master tire assembly 10B is an ellipse composed of a short diameter d and a long diameter D. As shown in FIG. 6, the upper left split ring 41 includes a large number (seven in this example) of third bolts 34 and adjusts the tightening degree of these third bolts 34 based on the ellipse data. Thus, an ellipse composed of the minor axis d and the major axis D can be easily obtained.

  Further, as shown in FIG. 8A, a gap a is formed only in the upper left split ring 41, and the upper right split ring 42, the lower left split ring 43, and the lower right split ring 44 are brought into close contact with the inner diameter ring 20, thereby further Another form of the master tire assembly 10C is obtained. The tire portion 60 is locally inclined at an angle θ.

  As shown in FIG. 8B, which is a view from the arrow b in FIG. 8A, the master tire assembly 10C is a perfect circle having a diameter d in the bottom view, and is a view from the arrow c in FIG. As shown in FIG. 8C, in the plan view, the right half of the figure is a semicircle with a diameter d, and the left half of the figure is a semi-ellipse with a long diameter D.

  As described above, the master tire assembly 10 according to the present invention can have various non-circular shapes by the first to third bolts 27, 31, and 34. For convenience of drawing, two forms of the master tire assembly 10B and the master tire assembly 10C have been shown, but it is desirable to similarly produce five types of five non-circular master tire assemblies in the same manner. .

Next, a structural example of the uniformity measuring apparatus will be described.
As shown in FIG. 9, the uniformity measuring apparatus 70 includes a bed 71, a rail 72 laid on the upper surface of the bed 71, and a moving table 74 mounted on the rail 72 via guide members 73 and 73, A C-type support column 75 extending upward from one end of the moving table 74, an upper support member 76 fixed to the upper end of the C-type support column 75 and extending so as to be parallel to the moving table 74, and the upper support material 76 and A support shaft 78 that is vertically transferred to the moving table 74 via load cells 77, 77, a driven drum 81 that is attached to the support shaft 78 via bearings 79, 79, and a bracket 82 that extends upward from the bed 71 A drive source 84 attached to the bracket 82 so that the drive shaft 83 is horizontal, a feed screw 85 that is rotated by the drive shaft 83 and screwed into the C-type support column 75, and a bracket 2, a housing 86 attached to the bed 71 at a position opposite to the position 2, a rotary shaft drive source 87 provided in the housing 86 and including an encoder, and a rotary shaft drive mounted on the upper portion of the housing 86 so as to be rotatable about a vertical axis. A rotating shaft 88 rotated by a source 87, a disc-shaped base 89 integrally formed on the rotating shaft 88, and a cylindrical portion extending upward from the center of the disc-shaped base 89 and replacing the axle 90, a disk 91 fitted in the cylindrical portion 90, and a bolt 92 and a nut 93 that replace the hub bolt connecting the disk 91 and the disk-shaped base 89.

In addition, a gear 94 is provided on the driven drum 81, and an encoder (or pulse pickup) 95 that detects the teeth of the gear 94 is provided on the upper support member 76.
The load cells 77 and 77 provided on the upper support member 76 and the movable table 74 are so-called three-dimensional load sensors, and can detect the three-dimensional direction (direction) of the applied force and the magnitude of the force. It is a sensor.

  In FIG. 9, the master tire assembly 10 is mounted on the disk-shaped base 89, the disc 91 is mounted, and the bolt 92 is mounted while the axle shaft insertion hole 22 is fitted in the cylindrical portion 90 and the hub bolt insertion hole 23 is further inserted into the bolt 92. Tighten the nut 93. As a result, the master tire assembly 10 (or 10B, 10C) can be set on the rotating shaft 88.

Next, the moving base 74 is advanced by the drive source 84, and the driven drum 81 is pressed against the tire portion 60 with a predetermined load (for example, 5000 N). Subsequently, the master tire assembly 10 is rotated by the rotating shaft drive source 87. Then, the driven drum 81 is rotated. The rotation angle and the rotation amount are detected by the encoder 95.
The force and direction applied to the driven drum 81 are continuously measured by the load cells 77 and 77.
The uniformity measuring apparatus 70 having the above configuration is widely put into practical use. The uniformity measuring device 70 may have a different structure.

The RFV force obtained by analyzing the data obtained by the encoder 95 and the load cells 77 and 77 is as shown in FIG.
As shown in FIG. 10, during one rotation, a fluctuation value (maximum) of b was detected on the plus side and a fluctuation value (maximum) of c was detected on the minus side.

  In the present invention, the master tire assembly 10 is regarded as an N (mass) master. Then, b on the plus side and c on the minus side are values to be calibrated in the uniformity measuring apparatus 70. Therefore, the load cells 77 and 77 are calibrated so that b and c become zero. Similar processing is performed for the LFV (the same applies hereinafter). This process is called “zero adjustment”.

When the master tire assembly 10 was measured with the uniformity measuring device 70 of FIG. 9 after the zero point correction, as shown in FIG. 11, the variation value became zero.
That is, the uniformity measuring apparatus 70 has been adjusted to zero.

  Next, in FIG. 9, the master tire assembly 10 is removed, and the master tire assembly 10B is placed thereon. Then, the master tire assembly 10 </ b> B is measured by the uniformity measuring device 70.

Then, the curve F shown in FIG. 12 was obtained. Since the master tire assembly 10B is artificially made non-circular, a relatively large variation value appears. However, it is not necessary to adjust the load cells 77 and 77 based on the curve F.
The shape data of the master tire assembly 10B and the data of FIG. 12 (curve F etc.) are stored as a set.

  Next, in FIG. 9, the master tire assembly 10B is removed, and the master tire assembly 10C is mounted. Then, the master tire assembly 10 </ b> C is measured by the uniformity measuring device 70.

  Then, the curve G shown in FIG. 13 was obtained. The shape data of the master tire assembly 10C and the data (curve G and the like) in FIG. 13 are stored as a set.

  If there are 5 types of master tire assemblies, 5 sets of data are stored.

With the above, "basic data" was created. The basic data creation method can be summarized as follows.
○ How to create basic data:
A preparation step of preparing a uniformity measuring device 70 as shown in FIG. 9;
As shown in FIG. 5, using the first to third bolts 27, 31, 34, the master tire assembly 10 is properly aligned so that the inner peripheral surface of the outer ring 40 is in close contact with the outer peripheral surface of the inner ring 20. A rounding process to make a circle,
As shown in FIG. 10, the uniformity measurement device 70 measures the maximum value of the radial force variation and the maximum value of the lateral force variation of the master tire assembly 10 that has been made circular. Process,
As shown in FIG. 11, the load cell mounted on the uniformity measuring apparatus is adjusted so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the first measurement process are zero. Zero point adjustment process
As shown in FIG. 7, the first to third bolts 27, 31, 34 are used to create a gap a and a between the outer peripheral surface of the inner ring 20 and the inner peripheral surface of the outer ring 40. A first non-circularizing step for making the tire assembly 10B non-circular,
As shown in FIG. 12, the maximum value of the radial force variation and the lateral force variation of the non-circular master tire assembly 10B using the uniformity measuring device adjusted by the zero point adjusting step. A second measuring step for measuring the maximum value of
Stores the shape of the master tire assembly 10B in the first non-circularization process and the maximum value of radial force fluctuation and the maximum value of lateral force fluctuation (curve F, etc.) obtained in the second measurement process. A second measurement data storing step,
As shown in FIG. 8, a master tire assembly 10 </ b> C is created by using the first to third bolts 27, 31, 34 to create a gap a between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring. A second non-circularization step for making the non-circular shape different from the shape in the first non-circularization step;
As shown in FIG. 13, the maximum fluctuation in the radial force of the master tire assembly 10 </ b> C made non-circular in the second non-circularization step using the uniformity measuring device adjusted in the zero point adjustment step. A third measuring step for measuring the maximum value and lateral force variation;
The shape of the master tire assembly 10C in the second non-circularization process and the maximum value of radial force fluctuation and the maximum value of lateral force fluctuation (curve C, etc.) obtained in the third measurement process are stored. And a third measurement data storing step.

○ Normal uniformity measurement:
The uniformity measuring device 70 can be put to practical use because the zero point adjustment has been completed. Therefore, the master tire assembly 10 shown in FIG. 9 is removed, and the actual tire assembly 100 shown in FIG. 14 is placed to measure the uniformity.

  As shown in FIG. 14, the tire assembly 100 includes a tire 101 and a wheel 102 incorporated in the tire 101. Since the tire 101 is assumed to be uneven and the wheel 102 is also assumed to be uneven, the actual tire assembly 100 has a certain variation value. If this fluctuation value is within the threshold value, normal uniformity measurement is carried out in such a manner that it is acceptable, and if it is outside the threshold value, it is rejected.

If normal uniformity measurement is continued for a certain period of time, the uniformity measurement apparatus 70 will inevitably be out of order.
Therefore, it is necessary to calibrate the uniformity measuring apparatus 70 periodically or in a timely manner. According to the present invention, calibration based on absolute values can be performed. The procedure will be described next.

When the uniformity measuring apparatus 70 shown in FIG. 9 is a calibration target apparatus, first, zero point adjustment is performed. That is, a master assembly 10 having a round shape shown in FIG. 5 is prepared. Then, this master assembly 10 is attached to a uniformity measuring apparatus 70 that requires calibration, and the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation are measured.
As shown in FIG. 15A, during one rotation, a fluctuation value (maximum) of b1 was detected on the plus side and a fluctuation value (maximum) of c1 was detected on the minus side. The load cell (FIG. 9, reference numerals 77 and 77) is calibrated so that b1 and c1 become zero. As a result, it became like FIG.15 (b).

Next, basic data (curve F and the like) shown in FIG. 12 and a master tire assembly 10B shown in FIG. 7 are prepared.
And the master tire assembly 10B is attached to the uniformity measuring apparatus 70, and a uniformity measurement is implemented.

  As a result, data indicated by the thick curve H shown in FIG. 16 was obtained. A fine line curve F is a basic data curve shown in FIG. There was a difference in b2 on the plus side and a difference in c2 on the minus side. Since the master tire assembly 10B is one of the N prototypes, the uniformity measuring device 70 is calibrated so that b2 and c2 become zero.

In principle, the calibration applied to the uniformity measuring apparatus 70 requiring calibration includes the zero point adjustment described with reference to FIG. 15 and the calibration described with reference to FIG.
However, in order to increase reliability, it is recommended to perform calibration at least twice under different conditions.

In the second time, basic data (curve G and the like) shown in FIG. 13 and a master tire assembly 10C shown in FIG. 8 are prepared.
And the master tire assembly 10C is attached to the uniformity measuring apparatus 70, and a uniformity measurement is implemented.

  As a result, data indicated by a thick curve J shown in FIG. 17 was obtained. A thin line curve G is a basic data curve shown in FIG. There was a difference in b3 on the plus side and a difference in c3 on the minus side. Since the master tire assembly 10C is also one of the N prototypes, the uniformity measuring device 70 is calibrated so that b3 and c3 become zero.

  As described above, it is possible to perform absolute calibration periodically or timely to the uniformity measuring apparatus 70 that has been put to practical use. This calibration method can be summarized as follows.

○ Regular or timely calibration method for uniformity measuring equipment:
A first pre-calibration measurement step (FIG. 15) for measuring the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the rounded master tire assembly by the uniformity measuring apparatus that requires calibration. (A)),
Zero before calibration for adjusting the load cell mounted on the uniformity measuring device so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the first pre-calibration measurement step are zero. A point adjustment step (FIG. 15B);
Based on the information stored in the second measurement data storage step, a master preparation step of preparing a master tire assembly having the same form as that in the first non-circularization step shown in FIG.
Before the second calibration, the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the master tire assembly prepared in the master preparation step are measured using a uniformity measuring device that requires calibration. The measurement process (FIG. 16, bold curve);
The maximum value obtained in the second pre-calibration measurement step is compared with the maximum value stored in the second measurement data storage step so that both maximum values match, that is, the differences b2 and c2 in FIG. It consists of a calibration process for calibrating the load cell so that it becomes zero. Zero point adjustment and at least one calibration are performed.

  As described above, the calibration is performed once. However, the calibration may be performed twice or more.

As shown in FIG. 18, the master tire assembly 10 may be a tire having a groove 68 in the tire portion 60.
Further, as shown in FIG. 19, the upper left split ring 41 in the master tire assembly 10 may be a 2/3 arc (240 °) different from the semicircular arc (180 °). At this time, the upper right split ring 42 forms a 1/3 arc (120 °). Note that 2/3 or 1/3 may be a fraction different from 1/2 and can be changed as appropriate.

  Further, as shown in FIG. 20, the master tire assembly 10 may have a form in which FIGS. 18 and 19 are combined. 18 to 20, the same elements as those in FIG.

  The present invention is suitable for calibration of a uniformity measuring apparatus for measuring the uniformity of a wheel.

  DESCRIPTION OF SYMBOLS 10 ... Master tire assembly whose outer shape is a perfect circle, 10B, 10C ... Master tire assembly whose outer shape is a non-circular shape, 20 ... Inner diameter ring, 21 ... Boss part, 22 ... Axle insertion hole, 23 ... Hub bolt insertion hole , 24 ... disk part, 25 ... axle, 26 ... cylindrical part, 26a, 26b ... end face of cylindrical part, 27 ... first bolt, 28 ... upper first female thread part, 29 ... lower first female thread part, 31 ... second Bolt, 32 ... upper second bolt hole, 33 ... lower second bolt hole, 34 ... third bolt, 35 ... upper third female screw portion, 36 ... lower third female screw portion, 37 ... outer peripheral surface of inner ring, 40 ... Outer diameter ring, 41 ... Upper left split ring, 42 ... Upper right split ring, 43 ... Lower left split ring, 44 ... Lower right split ring, 45 ... Second female thread portion, 46 ... Split tube portion, 47 ... First bolt hole, 48 ... inner flange part, 49 ... outer flange part, 51 Central side flange portion, 60 ... tire section, 70 ... uniformity measuring apparatus, 77 ... load cell, 100 ... tire assembly.

Claims (3)

A master tire assembly comprising an inner diameter ring, an outer diameter ring attached to the outer peripheral surface of the inner diameter ring, and a tire portion attached to the outer peripheral surface of the outer diameter ring, and used for calibration of the uniformity measuring device,
The inner ring is
A disc portion having an axle insertion hole and a hub bolt insertion hole;
A cylindrical portion extending along the axle from above and below the periphery of the disc portion when the disc portion is held horizontally;
A plurality of upper first female screw portions and lower first female screw portions that are provided on each of the upper and lower end faces of the cylindrical portion and into which a first bolt extending along the axle is screwed;
A plurality of upper second bolt holes and lower second bolt holes which are provided in the cylindrical portion at the upper and lower sides of the disk portion and extend perpendicularly to the axle and through which the second bolts are inserted;
A plurality of upper third female threads and lower third female threads provided in the cylindrical portion above the upper second bolt hole or below the lower second bolt hole and extending so as to be orthogonal to the axle and screwed in the third bolt. Consists of
The outer diameter ring is
It consists of a left upper split ring, an upper right split ring, a lower left split ring and a lower right split ring which are divided into two parts on the horizontal line after dividing the cylinder into two parts,
Each of these split rings
A split tube portion extending along an outer peripheral surface of the inner ring and having a second female screw portion into which the second bolt is screwed;
An inner flange portion having a first bolt hole extending from one end of the divided cylindrical portion so as to cover the end surface of the cylindrical portion and having the first bolt inserted therethrough;
An outer flange portion extending outward from the outer periphery of the inner flange portion;
It consists of a center side flange portion extending outward from the other end of the divided cylinder portion,
The master tire assembly, wherein the tire portion is a solid rubber body integrally formed on an outer peripheral surface of the outer diameter ring after being attached to the inner diameter ring. A preparation step of preparing a master tire assembly according to claim 1 and a uniformity measuring device for measuring uniformity of the tire assembly for practical use;
Using the first to third bolts, a rounding step for making the master tire assembly a perfect circle so that the inner peripheral surface of the outer diameter ring is in close contact with the outer peripheral surface of the inner diameter ring;
A first measurement step of measuring a maximum value of a radial force variation and a maximum value of a lateral force variation of the master tire assembly that has been rounded by the uniformity measuring device;
A zero point adjusting step of adjusting a load cell mounted on the uniformity measuring apparatus so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the first measuring step are zero; ,
A first non-circular circle that uses the first to third bolts to create a gap between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring to make the master tire assembly non-circular. Conversion process,
Using the uniformity measuring device adjusted by the zero point adjustment step, the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the non-circular master tire assembly are measured. A second measuring step,
Second measurement for storing the shape of the master tire assembly in the first non-rounding step and the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the second measuring step. Data storage process;
Using the first to third bolts, a gap is formed between the outer peripheral surface of the inner diameter ring and the inner peripheral surface of the outer diameter ring. A second non-rounding step for making a non-round shape with a shape different from the shape;
Using the uniformity measuring device adjusted by the zero point adjustment step, the maximum value of the radial force variation and the lateral direction of the master tire assembly non-rounded by the second non-rounding step A third measuring step for measuring the maximum value of force fluctuation;
The third measurement for storing the shape of the master tire assembly in the second non-rounding step and the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the third measuring step. Data storage process,
A basic data creation method using a master tire assembly, wherein at least two types of basic data are stored in the second measurement data storage step and the third measurement data storage step. A calibration method for a uniformity measuring apparatus that calibrates a uniformity measuring apparatus that requires calibration using the basic data created by the basic data creating method using the master tire assembly according to claim 2,
A first pre-calibration measurement step of measuring the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the rounded master tire assembly by the uniformity measuring device that requires calibration; ,
The load cell mounted on the uniformity measuring apparatus that requires the calibration is adjusted so that the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation obtained in the measurement process before the first calibration become zero. Zero point adjustment process before calibration,
Based on the information stored in the second measurement data storage step, a master preparation step of preparing a master tire assembly having the same form as that in the first non-rounding step,
Before the second calibration, the maximum value of the radial force fluctuation and the maximum value of the lateral force fluctuation of the master tire assembly prepared in the master preparation step are measured using a uniformity measuring device that requires calibration. Measuring process;
Comparing the maximum value obtained in the second pre-calibration measurement process with the maximum value stored in the second measurement data storage process, and calibrating the load cell so that both maximum values match,
A calibration method for a uniformity measuring apparatus, characterized by performing zero point adjustment and at least one calibration.

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