Accuracy Inspection Method for Tire Testing Machine

Abstract

To provide a method for checking the accuracy of a tire test machine that can check the accuracy of a test machine by changing the phase of a spindle and a tire without delivering one tire from a test position.SOLUTION: In the method for checking the accuracy of a tire test machine 1, after a first test is run on a tire, an upper spindle 22 moves upward from a tire T. After that, a lower spindle 21 and the tire T rotate by a predetermined angle. Also, the phase of the lower spindle 21 is adjusted to the phase of the upper spindle 22 while the conveyor 8 is lifted and holds the tire T temporarily. The tire T is supported by the lower spindle 21 again and the upper spindle 22 is moved down so that a second test is run.SELECTED DRAWING: Figure 19

Description

Technical Field

[0001] The present invention relates to a method for inspecting the accuracy of a tire testing machine for performing a predetermined test on a tire.

Background Art

[0002] Conventionally, a tire testing machine for measuring the uniformity of a tire has been known. The tire testing machine includes a spindle that rotatably supports a tire around a rotation center axis extending in the vertical direction, a rotary drum that is rotatable around a rotation center axis parallel to the rotation center axis of the spindle and can be brought into contact with the outer peripheral surface of the tire, and a load cell capable of measuring the load applied to the rotary drum. There is also a device having a load cell on the spindle side.

[0003] When the tire mounted on the spindle is filled with air and the rotary drum is pressed against the outer peripheral surface of the tire, the tire is rotated by the spindle, and the load cell measures the load fluctuation data of the tire. Based on the measured load fluctuation data, the uniformity of the tire is evaluated. The spindle has an upper spindle and a lower spindle. When mounting the tire on the spindle, an upper rim and a lower rim corresponding to the tire size are mounted on both side surfaces of the tire, respectively, and the spindle rotatably supports the tire via these rims.

[0004] Patent Document 1 discloses a method for inspecting the accuracy of the above-described tire testing machine (tire uniformity machine). In this method, first, a single tire is carried into the test zone by a transfer device, the upper spindle and the lower spindle are brought closer in the axial direction to clamp the tire, and the spindle is rotated to measure the first tire uniformity. Then, the rotation of the spindle is stopped, both spindles are separated, and the tire is carried out of the test zone by the transfer device without rotating the tire and is made to wait at the standby position. Next, with both spindles in contact, they are rotated by a predetermined angle to shift the phase of the spindle, then both spindles are separated, and the tire at the standby position is carried back into the test zone. Then, the tire is clamped again by both spindles, and the second tire uniformity is measured. In this way, the tire uniformity is measured n times for one tire, and the tire uniformity is measured n times in the same manner for m tires, thereby obtaining a total of n×m tire uniformity data, and the accuracy of the tire testing machine is verified.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the technology described in Patent Document 1, each time a test is performed on a single tire by changing the phase between the tire and the spindle, operations such as carrying the tire out of the test position and carrying it back into the test position again, and adjusting the axial position of the tire to the test position occur. Therefore, there is a problem that it takes a lot of time to inspect the accuracy of the tire testing machine.

[0007] The present invention has been made in view of the above problems, and an object thereof is to provide a method for inspecting the accuracy of a tire testing machine that can perform an accuracy inspection of the testing machine by changing the phase between the spindle and the tire without removing one tire from the test position.

Means for Solving the Problems

[0008] The present invention provides a method for inspecting the accuracy of a tire testing machine that rotates a tire about its rotation center axis in a horizontal posture where the rotation center axis of the tire extends in the vertical direction at a predetermined tire test position and performs a predetermined test on the tire. The accuracy inspection method includes a preparation step, a loading step, a first delivery step, a tire clamping step, a test step, an upper spindle separation step, a lower spindle rotation step, a second delivery step, a repetition step, and an analysis step. In the preparation step, as the tire testing machine, a transport unit capable of horizontally transporting the tire in the horizontal posture through the tire test position, a lower spindle that supports a lower portion of the tire in the horizontal posture at the tire test position so that the tire can rotate about the rotation center axis, and an upper spindle that supports an upper portion of the tire in the horizontal posture at the tire test position are prepared. In the loading step, one tire is loaded into the tire test position by the transport unit. In the first delivery step, the transport unit is relatively moved vertically with respect to the lower spindle, and the one tire is delivered from the transport unit to the lower spindle. In the tire clamping step, the upper spindle is relatively lowered with respect to the lower spindle, and the one tire is clamped by the lower spindle and the upper spindle. In the test step, the lower spindle, the one tire, and the upper spindle are integrally rotated, the test is performed on the one tire, and test data is acquired. In the upper spindle separation step, the upper spindle is relatively raised with respect to the lower spindle, and the upper spindle is separated from the tire. In the lower spindle rotation step, the lower spindle is relatively rotated by a predetermined angle with respect to the upper spindle. In the second delivery step, the transport unit is relatively moved vertically with respect to the lower spindle, and the one tire is delivered from the lower spindle to the transport unit. In the repetition step, the first delivery step, the tire clamping step, the test step, the upper spindle separation step, the lower spindle rotation step, and the second delivery step are sequentially repeated so that the test is performed a preset number of times on the one tire.In the analysis step, based on the test data for the number of test times obtained through the repetition step, the accuracy of the tire testing machine is analyzed.

[0009] According to this method, every time a test is performed by changing the phase between the tire and each spindle for one tire, operations such as removing the tire from the tire test position and then re-introducing it into the tire test position, or frequently adjusting the axial position of the tire to the tire test position do not occur. Therefore, it is possible to reduce the time required for the accuracy inspection of the tire testing machine.

[0010] In the above method, before the first transfer step, a phase adjustment step of aligning the phases of the upper spindle and the lower spindle to a predetermined specific phase may be further provided. The repetition step may include repeating the phase adjustment step, the first transfer step, the tire clamping step, the test step, the upper spindle separation step, the lower spindle rotation step, and the second transfer step in this order a preset number of test times for the one tire.

[0011] According to this method, since it is possible to perform a plurality of tests on each tire with the phases of the upper spindle and the lower spindle aligned, it is possible to analyze the accuracy variations focusing on the phases between the spindle and the tire. Also, even when it is necessary to match the phases of the upper spindle and the lower spindle in order to set the distance between the upper and lower spindles according to the width of the tire, the accuracy inspection of the tire testing machine can be performed by making the phases between each spindle and the tire different.

[0012] In the above method, the preparation step includes preparing, as one of the lower spindle and the upper spindle, a cylindrical insertion portion having an insertion outer peripheral surface that constitutes the outer peripheral surface of the insertion portion and is inserted into the other spindle different from the one spindle, the insertion portion being centered on the rotation center axis; and preparing, as the other spindle, a cylindrical spindle inner peripheral surface that defines an opening facing the insertion portion of the one spindle in the axial direction of the rotation center axis and an internal space capable of receiving the insertion portion through the opening, and a locking portion that constitutes at least a part of the spindle inner peripheral surface and is capable of locking the insertion portion inserted into the internal space so as to restrain the one spindle in the axial direction.

[0013] According to this method, by inserting the insertion portion of one spindle into the internal space of the other spindle and locking the insertion portion with the locking portion, the relative position between the lower spindle and the upper spindle can be easily restrained.

[0014] In the above method, in the preparation step, as the one spindle, the insertion part includes a plurality of insertion engaging parts that respectively extend in the axial direction of the rotation center axis and are arranged at intervals in the rotation direction of the tire, and each of the insertion engaging parts constitutes a part of the insertion outer peripheral surface, and each of the insertion engaging parts includes a plurality of engaging protrusions that respectively extend along the rotation direction and are arranged adjacent to each other in the axial direction; and a plurality of insertion recesses that are respectively arranged so as to extend in the axial direction between the insertion engaging parts adjacent to each other in the rotation direction among the plurality of insertion engaging parts, and each of the insertion recesses constitutes a part of the insertion outer peripheral surface, and each of the insertion recesses has a shape that is recessed radially inward with respect to the plurality of insertion engaging parts when viewed from the axial direction. Prepare a spindle having such a structure; as the other spindle, the lock part includes a plurality of lock engaging parts that respectively extend in the axial direction on the inner peripheral surface of the spindle and are arranged at intervals in the rotation direction, and each of the lock engaging parts includes a plurality of locking protrusions that respectively extend along the rotation direction and are arranged adjacent to each other in the axial direction; and a plurality of lock recesses that are respectively arranged on the inner peripheral surface of the spindle so as to extend in the axial direction between the lock engaging parts adjacent to each other in the rotation direction among the plurality of lock engaging parts, and each of the lock recesses has a shape that is recessed radially outward with respect to the plurality of lock engaging parts when viewed from the axial direction. Prepare a spindle having such a structure. The phase adjustment step may include adjusting the phases of the upper spindle and the lower spindle so that, when viewed from the axial direction, the plurality of insertion engaging parts of the one spindle respectively coincide with the plurality of lock recesses of the other spindle and the plurality of insertion recesses of the one spindle respectively coincide with the plurality of lock engaging parts of the other spindle, and an insertable state is achieved.

[0015] According to this method, the relative position in the axial direction between the lower spindle and the upper spindle can be easily set by a plurality of insertion engagement portions and a plurality of insertion recesses provided in the insertion portion of one spindle, and a plurality of locking engagement portions and a plurality of locking recesses provided in the locking portion of the other spindle. In particular, since a plurality of engagement protrusions are arranged adjacent to each other in the axial direction in the insertion engagement portion of the insertion portion, and a plurality of locking protrusions are arranged adjacent to each other in the axial direction in the locking engagement portion of the locking portion, by making the engagement positions of the protrusions different from each other in the axial direction, it becomes possible to easily change the interval between both spindles according to the width of the tire.

[0016] In the above method, the tire clamping step includes an insertion step of inserting the insertion portion of the one spindle along the axial direction into the internal space of the other spindle until the plurality of insertion engagement portions face the plurality of locking engagement portions in the rotational direction, a positioning step of relatively rotating the lower spindle with respect to the upper spindle so that the plurality of locking protrusions of the plurality of locking engagement portions of the other spindle engage with the plurality of engagement protrusions of the plurality of insertion engagement portions of the one spindle, respectively, and positioning the upper spindle and the lower spindle relatively in the axial direction according to the width of the one tire, and an air filling step of filling air into the one tire so that the upper spindle, the one tire, and the lower spindle can rotate integrally.

[0017] According to this method, after inserting the insertion portion of one spindle into the internal space of the other spindle, the interval between the upper spindle and the lower spindle can be easily fixed by relatively rotating the other spindle with respect to the one spindle.

[0018] In the above method, in the preparation step, as the one spindle, a spindle having a spiral shape centered on the rotation center axis such that the plurality of engaging protrusions of the plurality of insertion engaging portions incline in one direction in the axial direction as they advance in the rotation direction is prepared, and as the other spindle, a spindle having a spiral shape centered on the rotation center axis such that the plurality of locking protrusions of the plurality of locking engaging portions incline in the one direction as they advance in the rotation direction and having a spiral shape engageable with the plurality of engaging protrusions along the rotation direction is prepared. The phase adjustment step includes aligning the phases of the plurality of insertion engaging portions of one spindle and the plurality of locking recesses of the other spindle as viewed from the axial direction such that the spiral shape of the plurality of engaging protrusions and the spiral shape of the plurality of locking protrusions engage with each other in the positioning step, so that the upper spindle and the lower spindle are relatively positioned in the axial direction according to the width of the one tire.

[0019] According to this method, in the phase adjustment step, by aligning the phases of the plurality of insertion engaging portions of one spindle and the plurality of locking recesses of the other spindle, the insertion position of the insertion portion with respect to the internal space is matched, and the interval between the lower spindle and the upper spindle can be accurately adjusted according to the width of the tire.

Effect of the Invention

[0020] According to the present invention, there is provided a method for inspecting the accuracy of a tire testing machine that can perform an accuracy inspection of the testing machine by changing the phase between the spindle and the tire without carrying out one tire from the test position.

Brief Description of the Drawings

[0021]

Figure 1

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Mode for Carrying Out the Invention

[0022] Hereinafter, an embodiment of the tire testing machine 1 of the present invention will be described in detail with reference to the drawings. FIGS. 1, 2, and 3 are a plan view, a rear view, and a side view of the tire testing machine 1 according to the present embodiment. In each of the following drawings, the front-rear, up-down, and left-right directions are shown based on the tire T conveyed by the tire testing machine 1, but the directions do not limit the accuracy inspection method of the tire testing machine according to the present invention and the usage mode of the tire testing machine.

[0023] The tire testing machine 1 includes a main body frame 1S, a spindle 2, a tire conveying mechanism 3, a rotating drum 4, a lifting unit 50, a marking unit 60, a drum moving mechanism (not shown), and a load cell 4L. The tire testing machine 1 rotates the tire T (see FIG. 15) around the tire rotation center axis CL (rotation center axis) in a horizontal posture in which the tire rotation center axis CL of the tire T extends in the vertical direction at a predetermined tire test position P, and performs a predetermined test on the tire T.

[0024] The main body frame 1S is disposed at a substantially central portion of the tire testing machine 1, and a tire test position P is formed inside thereof. The main body frame 1S rotatably supports the spindle 2. The main body frame 1S includes a lower frame 100 (FIG. 3), a base frame 101 (FIG. 2), and an upper frame 102 (FIG. 2).

[0025] The spindle 2 rotatably supports the tire T around a reference rotation center axis 2S extending in the vertical direction at the tire test position P. The spindle 2 includes a lower spindle 21 (the other spindle, the second spindle) and an upper spindle 22 (one spindle, the first spindle) (Figs. 2 and 3). The lower spindle 21 is rotatably supported by the lower frame 100.

[0026] The tire conveying mechanism 3 is arranged along a horizontal conveying direction D1 so as to pass through the tire test position P in a plan view, and is capable of carrying the tire T in a horizontal posture into the tire test position P, while being capable of carrying the tire T out from the tire test position P along the conveying direction D1.

[0027] The rotating drum 4 is rotatably supported by the base frame 101 of the main body frame 1S. The rotating drum 4 is disposed to face the tire test position P (spindle 2) at a predetermined interval in a direction (left - right direction) substantially orthogonal to the conveying direction D1 of the tire T conveyed by the tire conveying mechanism 3. This rotating drum 4 is a cylindrical member rotatable around a rotation center axis extending in a direction (vertical direction) parallel to the reference rotation center axis 2S of the spindle 2, and a simulated road surface 4A (outer peripheral surface) on which the tire T travels is formed on its outer peripheral surface. When the simulated road surface 4A contacts the outer peripheral surface of the tire T, the rotating drum 4 is driven to rotate following the tire T. A drum moving mechanism (not shown) for horizontally pushing and moving the rotating drum 4 is provided on the side of the rotating drum 4, and the drum moving mechanism can move the rotating drum 4 closer to and away from the tire T.

[0028] The load cells 4L (load measuring devices) are respectively arranged on the vertical extension line of the rotation center axis of the rotating drum 4 (only the upper side is shown in FIG. 1), and measure the load received by the rotating drum 4 from the tire T. The load cells 4L are used to support the rotating drum 4 on the main body frame 1S, and are provided one by one on the upper and lower parts of the rotating drum 4 to measure the load in the axial vertical direction acting on the rotating drum 4. That is, the tire testing machine 1 according to the present embodiment uses a combination of a ball screw and a motor (not shown) to bring the rotating drum 4 close to the spindle 2, and while bringing the tire T into contact with the simulated road surface 4A of the rotating drum 4, measures the load fluctuation during tire rotation with the load cells 4L, thereby being configured as a tire uniformity machine for evaluating the uniformity of the tire T.

[0029] The tire conveying mechanism 3 has a belt conveyor type structure. The tire conveying mechanism 3 includes a loading conveyor 7, a conveying conveyor 8, an unloading conveyor 9, a loading frame 7S, and an unloading frame 9S. In FIG. 1, the tire T is conveyed from the rear side (upstream side) to the front side (downstream side).

[0030] The loading conveyor 7 conveys the tire T toward the tire test position P. The tire T conveyed by the loading conveyor 7 is delivered to the upstream part of the conveying conveyor 8. The conveying conveyor 8 receives the tire T from the loading conveyor 7 and conveys the tire T into the tire test position P. The conveying conveyor 8 is controlled by a control unit 90 described later to temporarily stop the tire T at the tire test position P. Thereafter, when a predetermined test is performed on the tire T, the conveying conveyor 8 conveys the tire T further downstream. The tire T conveyed by the conveying conveyor 8 is delivered to the unloading conveyor 9. The unloading conveyor 9 receives the tire T from the conveying conveyor 8 and conveys the tire T further downstream.

[0031] Note that the loading conveyor 7, the conveying conveyor 8, and the unloading conveyor 9 are circularly driven by a drive unit (not shown) of the tire conveying mechanism 3. Further, the conveying conveyor 8 can be lifted by an air cylinder (not shown) included in the drive unit. The tire T carried into the tire test position P is delivered to the lower spindle 21 by the lowering of the conveying conveyor 8. FIG. 3 shows a state where the conveying conveyor 8 has moved to the lowest lower position. When the conveying conveyor 8 is moved to the uppermost upper position, the conveying conveyor 8 is arranged at the same height as the loading conveyor 7 and the unloading conveyor 9, and can convey the tire T. Further, the loading conveyor 7, the conveying conveyor 8, and the unloading conveyor 9 are composed of a pair of belts arranged side by side at an interval narrower than the outer diameter of the tire T. Also, as described above, the interval between the pair of belts of the conveying conveyor 8 is set wider than the outer diameter of the lower spindle 21 so that the tire T can be delivered by the lifting (vertical movement) of the conveying conveyor 8.

[0032] The loading frame 7S supports the loading conveyor 7 so as to be rotatable, and the unloading frame 9S supports the unloading conveyor 9 so as to be rotatable. Further, the unloading frame 9S supports a marking unit 60 (FIG. 3) that applies a predetermined marking to the tire T according to the test result at the tire test position P.

[0033] The lifting unit 50 (FIG. 2) supports the upper spindle 22 so as to be liftable and rotatable. The lifting unit 50 can move up and down along a pair of front and rear guide frames 102A of the upper frame 102 in FIG. 2. The detailed structure of the lifting unit 50 will be described later.

[0034] FIG. 4 is a side view of a state where the upper rim 62 is supported by the upper spindle 22 of the tire testing machine 1 according to the present embodiment. FIGS. 5, 6, and 7 are a plan view, a side sectional view, and a perspective view of the lock piece 250 of the tire testing machine 1 according to the present embodiment. FIG. 8 is a side sectional view of a state where the lower rim 61 and the upper rim 62 are respectively supported by the lower spindle 21 and the upper spindle 22 of the tire testing machine 1 according to the present embodiment.

[0035] The lower spindle 21 has a lower holding flange 210A (FIG. 8) (lower holding portion) capable of holding a lower rim 61 that is attached to a lower bead portion, which is a bead portion located on the lower side of the tire T in the horizontal posture, and supports the tire T via the lower rim 61 so that the tire T can rotate around the reference rotation center axis 2S.

[0036] The upper spindle 22 has an upper holding flange 221 (FIG. 8) (upper holding portion) capable of holding an upper rim 62 that is attached to an upper bead portion, which is a bead portion located on the upper side of the tire T in the horizontal posture, and supports the tire T via the upper rim 62 so that the tire T can rotate around the reference rotation center axis 2S.

[0037] When the tire T is disposed at the tire test position P, the tire rotation center axis CL of the tire T coincides with the reference rotation center axis 2S of the spindle 2. The tire tester 1 has a plurality of types of lower rims 61 and upper rims 62 according to the size (outer diameter, inner diameter, width), shape, etc. of the tire T to be tested at the tire test position P, and appropriate lower rims 61 and upper rims 62 are disposed at the tire test position P according to each tire T.

[0038] The upper spindle 22 has an upper spindle base end portion 220 (FIG. 4), an upper holding flange 221, an insertion portion 222 inserted into the lower spindle 21, a guide piece 223, and an upper spindle engaging portion 224.

[0039] The upper spindle base end portion 220 has a cylindrical shape that constitutes the base end portion (upper end portion) of the upper spindle 22. As shown in FIG. 11, the upper spindle base end portion 220 is connected to the elevating unit 50.

[0040] The upper holding flange 221 is connected to the lower end of the upper spindle base end portion 220 and has a function of holding the ring-shaped upper rim 62.

[0041] The insertion part 222 is connected to the upper holding flange 221 from below. The insertion part 222 includes an insertion outer peripheral surface 222S (Fig. 4) and has a cylindrical shape centered on the reference rotation center axis 2S (tire rotation center axis CL). As shown in Fig. 8, when the insertion part 222 is inserted into the inside of the ring-shaped upper rim 62, the upper rim 62 reaches the upper holding flange 221 and is held.

[0042] The guide piece 223 is fixed to the lower end part of the insertion part 222 by a plurality of bolts V (Fig. 8) and is inserted into the internal space S (described later) of the lower spindle 21 together with the insertion part 222.

[0043] The upper spindle engaging part 224 (Fig. 4) is arranged at a substantially central part in the vertical direction of the insertion outer peripheral surface 222S of the insertion part 222. The upper spindle engaging part 224 has a plurality of insertion engaging parts 224A and a plurality of insertion recesses 224B.

[0044] The plurality of insertion engaging parts 224A each extend in the axial direction of the reference rotation center axis 2S and are arranged at intervals in the rotation direction of the tire T, and each constitute a part of the insertion outer peripheral surface 222S. The plurality of insertion engaging parts 224A each include a plurality of engaging protrusions 224AS that extend along the rotation direction and are adjacent to each other in the axial direction. The plurality of engaging protrusions 224AS in the plurality of insertion engaging parts 224A have a spiral shape centered on the reference rotation center axis 2S so as to incline in one direction (upward direction) in the axial direction as they proceed in the rotation direction of the upper spindle 22 (refer to the arrow in Fig. 4).

[0045] On one hand, the plurality of insertion recesses 224B are respectively arranged so as to extend in the axial direction between the insertion engagement portions 224A that are adjacent to each other in the rotational direction among the plurality of insertion engagement portions 224A, and constitute a part of the insertion outer peripheral surface 222S. The plurality of insertion recesses 224B each have a shape that is recessed radially inward with respect to the plurality of insertion engagement portions 224A when viewed from the axial direction. Note that both ends of the space (groove) formed between the plurality of engagement protrusions 224AS communicate with the spaces (depressions) defined by the adjacent insertion recesses 224B, respectively.

[0046] Furthermore, as shown in FIG. 8, the insertion portion 222 has an air introduction portion 225A and a plurality of air supply portions 225B. The air introduction portion 225A communicates with an air supply mechanism 55 described later and receives air supplied from the air supply mechanism 55 into the tire T (tire inner space). The plurality of air supply portions 225B communicate with the air introduction portion 225A and extend radially from the air introduction portion 225A. Each air supply portion 225B communicates with the tire inner space and supplies air. Note that the air introduction portion 225A and the plurality of air supply portions 225B also function as discharge portions for discharging excess air in order to prevent the tire T from bursting when the tire inner space is sufficiently filled with air, and control valves (not shown) for controlling the discharge of the air are arranged around these portions.

[0047] The lower spindle 21 (FIG. 8) has a cylindrical spindle body 210 and a ring-shaped lock piece 250 (locking portion) fixed to the spindle body 210. The spindle body 210 has a cylindrical inner peripheral surface 210S of the main body. The lock piece 250 has a cylindrical inner peripheral surface 250S of the piece (FIGS. 5 and 8). The inner peripheral surface 210S of the main body and the inner peripheral surface 250S of the piece constitute a cylindrical spindle inner peripheral surface 21S (FIG. 8). The spindle inner peripheral surface 21S defines an opening X (FIG. 8) that faces the insertion portion 222 of the upper spindle 22 in the axial direction and an internal space S that can receive the insertion portion 222 through the opening X, respectively. Note that the inner diameter of the spindle inner peripheral surface 21S is set to be slightly larger than the outer diameter of the insertion portion 222.

[0048] In this embodiment, the spindle body 210 includes a cylindrical lower holding flange 210A and a cylindrical lower spindle body portion 210B, and has an upper and lower two-part structure. As shown in FIG. 8, the lower holding flange 210A and the lower spindle body portion 210B are connected to each other by a plurality of bolts V. The lower holding flange 210A functions as a lower holding portion that holds the lower rim 61 from below. The upper portion of the lower holding flange 210A has an outer diameter smaller than that of the lower portion of the lower holding flange 210A. By inserting the upper portion of the cylindrical lower holding flange 210A into the center of the ring-shaped lower rim 61, the lower portion (flange portion) of the lower holding flange 210A holds the lower rim 61.

[0049] The lock piece 250 (FIG. 8) is arranged to be interposed between the lower holding flange 210A and the lower spindle body portion 210B, and as described above, the inner peripheral surface 250S of the piece constitutes a part of the spindle inner peripheral surface 21S. The lock piece 250 is capable of locking the upper spindle 22 inserted into the internal space S so as to restrain the upper spindle 22 in the axial direction. Note that the lock piece 250 rotates integrally with the spindle body 210 around the reference rotation center axis 2S.

[0050] The lock piece 250 has a plurality of lock engaging portions 250A and a plurality of lock recesses 250B (FIGS. 5 to 7). In this embodiment, the numbers of the plurality of insertion engaging portions 224A and the plurality of insertion recesses 224B, and the plurality of lock engaging portions 250A and the plurality of lock recesses 250B are all the same.

[0051] The plurality of locking engagement portions 250A extend in the axial direction on the inner peripheral surface 21S of the spindle and are arranged at intervals from each other in the rotational direction. The plurality of locking engagement portions 250A each include a plurality of locking protrusions 250AS (FIG. 6) that extend along the rotational direction and are arranged adjacent to each other in the axial direction. The plurality of locking protrusions 250AS of the plurality of locking engagement portions 250A are in a spiral shape centered on the reference rotation center axis 2S so as to incline upward (the one direction) as they proceed in the rotational direction of the lower spindle 21, and have a spiral shape that can engage with the plurality of engagement protrusions 224AS in the plurality of insertion engagement portions 224A along the rotational direction. In other words, the plurality of engagement protrusions 224AS and the plurality of locking protrusions 250AS described above are composed of a part (screw serrations) of a screw formed with a predetermined lead centered on the reference rotation center axis 2S.

[0052] As an example, when the lead is 1 / 2 pitch and the plurality of insertion recesses 224B and the plurality of locking recesses 250B are each arranged at six positions in the circumferential direction, when the lower spindle 21 is rotated 180 degrees in a state where the plurality of insertion engagement portions 224A and the plurality of locking engagement portions 250A are engaged, the distance (rim width) between the lower rim 61 and the upper rim 62 can be changed by 1 / 4 pitch. On the other hand, when the lead is 1 pitch and the plurality of insertion recesses 224B and the plurality of locking recesses 250B are each arranged at eight positions in the circumferential direction, when the lower spindle 21 is rotated 90 degrees in a state where the plurality of insertion engagement portions 224A and the plurality of locking engagement portions 250A are engaged, the distance (rim width) between the lower rim 61 and the upper rim 62 can be changed by 1 / 4 pitch.

[0053] The plurality of locking recesses 250B are respectively arranged on the inner peripheral surface 21S of the spindle so as to extend in the axial direction between the locking engagement portions 250A that are adjacent to each other in the rotational direction among the plurality of locking engagement portions 250A, and each have a shape that is recessed radially outward with respect to the plurality of locking engagement portions 250A when viewed from the axial direction (FIG. 5).

[0054] Note that the inner diameter of the lock engagement portion 250A is larger than the outer diameter of the aforementioned insertion recess 224B and smaller than the outer diameter of the insertion engagement portion 224A, and the inner diameter of the lock recess 250B is set to be larger than the outer diameter of the aforementioned insertion engagement portion 224A. The mutual relationship of these sizes is set so as to withstand the large axial forces generated in the upper spindle 22 and the lower spindle 21 by the air supplied to the tire inner space by the air supply mechanism 55.

[0055] FIG. 9 is an upper perspective view of the lifting unit 50 of the tire tester 1 according to the present embodiment, and FIG. 10 is an enlarged perspective view of a part of the lifting unit 50 of FIG. 9. FIG. 11 is a lower perspective view of the lifting unit 50 of the tire tester 1 according to the present embodiment, and FIG. 12 is an enlarged perspective view of a part of the lifting unit 50 of FIG. 11.

[0056] Referring to FIGS. 9 and 10, the lifting unit 50 includes a lifting bracket 510, a guided frame 511, a pair of front and rear diagonal frames 512, a base plate 515, a pair of upper spindle rotation phase sensors 516, four offset adjustment screws 517 in the front, rear, left, and right directions, and an air supply mechanism 55. Further, the aforementioned upper spindle 22 further has an upper spindle flange 227 (FIG. 10) connected to the upper spindle base end portion 220 (FIG. 4).

[0057] The lifting bracket 510, the guided frame 511, and the pair of front and rear diagonal frames 512 constitute a frame for lifting the upper spindle 22. The lifting bracket 510 has a rectangular shape extending in the front-rear and left-right directions. A plate-shaped bracket central portion 510A is disposed at the central portion of the lifting bracket 510 in the front-rear direction. The guided frame 511 is erected upward from the right side edge of the lifting bracket 510 and has a rectangular shape extending in the front-rear and vertical directions. The guided frame 511 is supported by a pair of guide frames 102A of the upper frame 102 so as to be movable (liftable) up and down. The pair of front and rear diagonal frames 512 connect the lifting bracket 510 and the guided frame 511 to maintain the rigidity of the lifting unit 50.

[0058] The base plate 515 is a member placed on the bracket central portion 510A of the elevating bracket 510, and has a disc-shaped portion and a cylindrical portion (base plate boss portion 515S). The center of the base plate 515 coincides with the reference rotation center axis 2S. As shown in FIGS. 11 and 12, a circular opening having an inner diameter smaller than the outer diameter of the base plate 515 is formed in the bracket central portion 510A, and the central portion (base plate boss portion 515S) of the base plate 515 is exposed so as to extend downward through the opening.

[0059] The upper spindle flange 227 is a member that is integral with the insertion portion 222 of the upper spindle 22 and is rotatable around the reference rotation center axis 2S. As shown in FIG. 10, the upper spindle flange 227 is placed on the base plate 515, and the center of the upper spindle flange 227 coincides with the reference rotation center axis 2S. Four holes 227A are opened at equal intervals along the circumferential direction in the upper spindle flange 227. The holes 227A are formed so as to penetrate the upper spindle flange 227 in the vertical direction. On the other hand, four base plate pins (not shown) that can be respectively inserted into the holes 227A are arranged on the base plate 515 so as to protrude upward.

[0060] When the four base plate pins are respectively inserted into the four holes 227A, the rotation of the upper spindle 22 including the upper spindle flange 227 around the reference rotation center axis 2S is blocked by the elevating bracket 510. On the other hand, when the upper spindle flange 227 of the upper spindle 22 moves relatively upward with respect to the base plate 515 and the four base plate pins are respectively detached from the four holes 227A, the upper spindle 22 including the upper spindle flange 227 is freely rotatable around the reference rotation center axis 2S.

[0061] Four offset adjustment screws 517 are arranged at the central portion 510A of the bracket so as to bias the outer peripheral surface of the base plate 515 radially inward. By adjusting the tightening amount of each offset adjustment screw 517, it becomes possible to adjust the offset amount of the upper spindle 22 including the upper spindle flange 227.

[0062] A pair of upper spindle rotation phase sensors 516 (FIG. 10) are arranged at intervals along the rotation direction of the upper spindle 22 (tire T) and are supported by a bracket 516S fixed on the base plate 515. On the other hand, the aforementioned upper spindle flange 227 has a detected portion 229 disposed on its outer peripheral portion. The detected portion 229 is an L-shaped sheet metal member and has a portion extending upward in the vicinity of the outer peripheral portion of the upper spindle flange 227. When the upper spindle flange 227 rotates around the reference rotation center axis 2S together with the upper spindle 22, the pair of upper spindle rotation phase sensors 516 detect the detected portion 229, thereby detecting the rotation and phase of the upper spindle flange 227. As an example, the upper spindle rotation phase sensor 516 includes a light emitting portion that emits detection light and a light receiving portion that receives the reflected light of the detection light.

[0063] The air supply mechanism 55 extends from a compressor (not shown) and supplies air to the aforementioned air introduction portion 225A through the inside of the cylinders of the upper spindle flange 227 and the upper spindle base end portion 220. That is, the air supply mechanism 55 is capable of filling air into the tire internal space, which is a space defined by the upper rim 62, the tire T, and the lower rim 61, in a state where the upper spindle 22 and the lower spindle 21 support the tire T via the upper rim 62 and the lower rim 61.

[0064] Referring to FIGS. 11 to 12, the lifting unit 50 further includes a lifting detection sensor 518 and a sensor bracket 518A. Also, at a position adjacent to the pair of upper spindle rotation phase sensors 516 on the base plate 515, a base plate notch portion 515A having a shape in which the base plate 515 is partially cut out is formed. The lifting detection sensor 518 is supported by the sensor bracket 518A so as to be disposed within the base plate notch portion 515A. The sensor bracket 518A supports the lifting detection sensor 518 at its tip end, and its base end is fixed to the lower surface portion of the bracket central portion 510A. The lifting detection sensor 518 is a sensor capable of detecting the lower surface portion of the upper spindle flange 227, and detects the relative lifting of the upper spindle flange 227 with respect to the base plate 515. In other embodiments, the base end of the sensor bracket 518A may be fixed to the base plate 515. In this case, even if the offset position of the base plate 515 is finely adjusted by the four offset adjustment screws 517, the lifting detection sensor 518 can stably detect the lower surface portion of the upper spindle flange 227.

[0065] FIG. 13 is a block diagram of the tire tester 1 according to the present embodiment. The tire tester 1 further includes a control unit 90, a plurality of tire detection sensors 91, an input unit 92, a lower spindle rotation drive unit 93, an upper spindle lifting drive unit 94, and a lower spindle rotation phase sensor 95.

[0066] The plurality of tire detection sensors 91 are respectively disposed in the conveyance path of the tire T conveyed by the tire conveyance mechanism 3, and detect the conveyance position of the tire T. When each tire detection sensor 91 detects the tire T, a predetermined detection signal is input to the control unit 90.

[0067] The input unit 92 inputs various command information to the control unit 90 when a predetermined test is performed on the tire T, and includes an operation unit and a display operated by an operator.

[0068] The lower spindle rotation driving unit 93 inputs a rotational driving force to the lower spindle 21, and is a driving unit that rotates the lower spindle 21 around the reference rotation center axis 2S during the locking engagement between the lower spindle 21 and the upper spindle 22 and during the test on the tire T. The lower spindle rotation driving unit 93 includes a motor and gears (not shown) driven by hydraulic pressure or electric power.

[0069] The upper spindle lifting and lowering driving unit 94 is a driving unit that relatively lifts and lowers the upper spindle 22 with respect to the lower spindle 21 through the lifting unit 50. The upper spindle lifting and lowering driving unit 94 includes a motor and gears (not shown) driven by hydraulic pressure or electric power. Above Figure 9, a bearing 513 that constitutes the upper spindle lifting and lowering driving unit 94 is shown. A feed screw is pivotally supported by the bearing 513 and is connected to an electric motor, a speed reducer, an encoder, etc. (not shown). In the present embodiment, a ball screw is used as the feed screw, but other types of screws such as trapezoidal screws may also be used. Also, mechanical element parts such as couplings may be used as appropriate. Further, instead of the electric motor, a driving force by hydraulic pressure such as a hydraulic motor or a hydraulic cylinder may be combined with a measuring device such as an encoder or a linear sensor and used.

[0070] The lower spindle rotation phase sensor 95 is mounted on the lower frame 100 and can detect the rotation and phase of the lower spindle 21. For this reason, a detected portion (not shown) detected by the lower spindle rotation phase sensor 95 is provided on the lower spindle 21. As an example, the lower spindle rotation phase sensor 95 includes a light emitting portion that emits detection light and a light receiving portion that receives the reflected light of the detection light.

[0071] The control unit 90 is composed of a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores a control program, a RAM (Random Access Memory) used as a working area for the CPU, and the like. Further, the control unit 90 is electrically connected to the aforementioned tire detection sensor 91, upper spindle rotation phase sensor 516, lifting detection sensor 518, input unit 92, lower spindle rotation phase sensor 95, tire transfer mechanism 3, lower spindle rotation drive unit 93, upper spindle lifting drive unit 94, air supply mechanism 55, and the like. By executing the control program stored in the ROM by the CPU, the control unit 90 functions as a tire transfer control unit 901, a lower spindle rotation control unit 902, an upper spindle lifting control unit 903, an air supply control unit 904, a storage unit 905, an accuracy inspection command unit 906, and a determination unit 907, respectively.

[0072] The tire transfer control unit 901 controls the aforementioned drive units provided in the tire transfer mechanism 3 to transfer the tire T by the loading conveyor 7, transfer conveyor 8, and unloading conveyor 9. Further, the tire transfer control unit 901 controls the lifting operation of the transfer conveyor 8 to lift and lower the transfer conveyor 8 between the aforementioned upper position and lower position, thereby transferring the tire T between the transfer conveyor 8 and the lower spindle 21.

[0073] The lower spindle rotation control unit 902 controls the lower spindle rotation drive unit 93 to rotate the lower spindle 21 around the reference rotation center axis 2S. When locking the lower spindle 21 and the upper spindle 22, the lower spindle rotation control unit 902 rotates the lower spindle 21 with the rotation of the upper spindle 22 blocked. On the other hand, when performing a predetermined test on the tire T, the lower spindle rotation control unit 902 rotates the lower spindle 21 and the upper spindle 22 integrally with the rotation of the upper spindle 22 permitted.

[0074] The upper spindle lifting control unit 903 controls the lifting drive unit 94 to control the lifting operation of the lifting unit 50 (upper spindle 22).

[0075] The air supply control unit 904 executes an operation of filling air into the inner space of the tire T by controlling the air supply mechanism 55.

[0076] The storage unit 905 stores various control parameters and the like referred to by the tire conveyance control unit 901, the lower spindle rotation control unit 902, the upper spindle lifting control unit 903, and the air supply control unit 904.

[0077] The accuracy inspection command unit 906 inputs a command signal to each functional unit in the control unit 90 in order to execute the accuracy inspection of the tire tester 1 described later.

[0078] The determination unit 907 executes various determination processes in the accuracy inspection executed by the accuracy inspection command unit 906.

[0079] <Regarding the uniformity test> FIG. 14 is a flowchart of the uniformity test of the tire tester 1 according to the present embodiment. FIG. 15 is a cross-sectional view showing a state in which the tire T is supported by the lower spindle 21 in the uniformity test of the tire tester 1. FIG. 16 is a cross-sectional view showing a state in which the upper spindle 22 is inserted into the lower spindle 21 in the uniformity test of the tire tester 1. FIG. 17 is a cross-sectional view showing a state in which the tire T is rotatably supported by the lower spindle 21 in the tire tester 1.

[0080] When performing the uniformity test on the tire T, as shown in FIG. 15, the lower rim 61 and the upper rim 62 are respectively held by the lower spindle 21 and the upper spindle 22 in advance, and the upper spindle 22 is in a state of being moved upward with respect to the lower spindle 21. At this time, in the upper spindle flange 227 of the upper spindle 22, the detected portion 229 (FIG. 10) is detected by the pair of upper spindle rotation phase sensors 516, and the four base plate pins of the base plate 515 are respectively inserted into the four hole portions 227A, so that the upper spindle 22 including the upper spindle flange 227 is rotated around the reference rotation center axis 2S. Its rotation is blocked at a specific rotation position.

[0081] On the other hand, the lower spindle rotation control unit 902 adjusts the rotation position of the lower spindle 21 in advance so that, corresponding to the upper spindle 22 being disposed at the above-mentioned specific rotation position, a plurality of insertion engagement portions 224A of the upper spindle 22 are respectively aligned with a plurality of lock recesses 250B of the lower spindle 21 and a plurality of insertion recesses 224B of the upper spindle 22 are respectively aligned with a plurality of lock engagement portions 250A of the lower spindle 21, and an insertable state is obtained. At this time, the rotation position of the lower spindle 21 can be adjusted by the lower spindle rotation phase sensor 95 detecting the detected portion of the lower spindle 21.

[0082] When the tire T is placed on the upstream end of the loading conveyor 7 (FIG. 1), the tire transfer control unit 901 controls the rotation of the loading conveyor 7 and the conveyor 8, and the tire T is carried into the tire test position P (step S1 in FIG. 14). At this time, the rotation of the conveyor 8 is stopped so that the tire rotation center axis CL of the tire T coincides with the reference rotation center axis 2S of the spindle 2. Thereafter, when the tire transfer control unit 901 lowers the conveyor 8, the tire T is transferred from the conveyor 8 to the lower spindle 21 (step S2 in FIG. 14). The tire T is placed on the lower rim 61 held by the lower spindle 21 (FIG. 15).

[0083] Next, the upper spindle lifting control unit 903 lowers the upper spindle 22 together with the lifting unit 50 (step S3 in FIG. 14), so that the distance between the upper rim 62 held by the upper holding flange 221 and the lower rim 61 held by the lower holding flange 210A becomes a predetermined distance according to the width of the tire T. The insertion portion 222 of the upper spindle 22 is inserted to a specific position in the internal space S of the lower spindle 21 (FIG. 16).

[0084] In this embodiment, as shown in FIG. 4, the engaging protrusion 224AS of the insertion engaging portion 224A of the upper spindle engaging portion 224 has more stages than the locking protrusion 250AS of the locking engaging portion 250A of the lock piece 250 (FIG. 6), and can support up to 16 stages of the width of the tire T. Further, as described above, the plurality of engaging protrusions 224AS and the plurality of locking protrusions 250AS are formed as part of a screw (screw serration) formed with a predetermined lead around the reference rotation center axis 2S, so that the distance (rim width) between the lower rim 61 and the upper rim 62 can be further changed at a quarter pitch.

[0085] Also, in the state shown in FIG. 16, the plurality of insertion engaging portions 224A (FIG. 4) face the plurality of locking recesses 250B (FIG. 5) in the radial direction centered on the reference rotation center axis 2S, respectively.

[0086] Next, the lower spindle rotation control unit 902 rotates the lower spindle 21 in the direction of the arrow in FIG. 4, so that a plurality of insertion engagement portions 224A face (fit) a plurality of lock engagement portions 250A in the radial direction centered on the reference rotation center axis 2S, and locks the lower spindle 21 and the upper spindle 22 (step S4 in FIG. 14) (spindle lock). Specifically, the lower spindle rotation control unit 902 rotates the upper spindle 22 by 30 degrees around the reference rotation center axis 2S. As a result, a plurality of locking protrusions 250AS of the plurality of lock engagement portions 250A of the lower spindle 21 receive a plurality of engagement protrusions 224AS of the plurality of insertion engagement portions 224A of the upper spindle 22 along the rotation direction in the space between the locking protrusions 250AS adjacent to each other in the axial direction, and engage with the plurality of engagement protrusions 224AS respectively. By this engagement, it becomes possible to relatively position the upper holding flange 221 of the upper spindle 22 and the lower holding flange 210A of the lower spindle 21 in the axial direction, and the interval between the lower rim 61 and the upper rim 62 is fixed.

[0087] Note that in a state where the interval between the lower rim 61 and the upper rim 62 is set according to the width of the tire T to be tested in this way, as shown in FIG. 16, a slight gap K is formed between the upper surface portion of the tire T and the upper rim flange 62F (see FIG. 4) formed on the outer peripheral portion of the upper rim 62.

[0088] Next, the air supply control unit 904 controls the air supply mechanism 55 to perform an air filling operation (step S5 in FIG. 14) (tire inflation). Specifically, the air supply control unit 904 fills air through the air supply mechanism 55 into the tire internal space, which is a space defined by the upper rim 62, the tire T, and the lower rim 61, in a state where the upper spindle 22 and the lower spindle 21 support the tire T via the upper rim 62 and the lower rim 61. As a result, as shown in FIG. 17, the tire T expands and the aforementioned gap K (FIG. 16) is filled. At this time, the upper bead portion and the lower bead portion of the tire T are in close contact with the upper rim 62 and the lower rim 61 respectively by the air. Note that the pressure in the tire internal space is detected by a pressure gauge (not shown), and the filling operation is performed until a predetermined set air pressure is reached.

[0089] Next, the upper spindle lifting control unit 903 controls the upper spindle lifting drive unit 94 to lower the lifting unit 50 by the lowering amount H (for example, 25 mm) shown in FIG. 17 (step S6 in FIG. 14). Since the vertical position of the upper spindle 22 including the upper spindle flange 227 is blocked by the engagement between the upper spindle engaging portion 224 and the lock piece 250, when the lifting unit 50 descends as described above, in FIG. 10, the upper spindle flange 227 rises (lifts) relative to the base plate 515. At this time, the lower surface portion of the upper spindle flange 227 moves away from above the lifting detection sensor 518, and by the change in the output signal of the lifting detection sensor 518, it is detected that the lifting unit 50 has descended by the lowering amount H. As a result, the four hole portions 227A of the upper spindle flange 227 are disengaged from the four base plate pins of the base plate 515, and the upper spindle 22 including the upper spindle flange 227 becomes freely rotatable around the reference rotation center axis 2S (release of the upper spindle 22).

[0090] In the state shown in FIG. 17, when the lower spindle rotation control unit 902 rotates the lower spindle 21, the tire T sandwiched between the lower rim 61 and the upper rim 62 rotates around the reference rotation center axis 2S integrally with the lower spindle 21 and the upper spindle 22. Then, as described above, by pressing the rotary drum 4 against the tire T, a uniformity test of the tire T can be executed (step S7 in FIG. 14). At this time, a large axial force is applied to the upper spindle 22 and the lower spindle 21 through the upper rim 62 and the lower rim 61 by the air filled in the tire internal space. As a result, the relative rotation around the reference rotation center axis 2S between the lower spindle 21 and the upper spindle 22 is suppressed by the contact surface pressure applied between the plurality of engagement protrusions 224AS and the plurality of locking protrusions 250AS, and the lower spindle 21 and the upper spindle 22 can rotate integrally. During the execution of the test on the tire T, the detection signals of the pair of upper spindle rotation phase sensors 516 are ignored.

[0091] After the test on the tire T is completed, the procedure is executed in the reverse order of the above. That is, when the lifting unit 50 rises relative to the upper spindle 22 and the rotation of the upper spindle 22 is restricted (step S8 in FIG. 14), the air supply control unit 904 controls the air supply mechanism 55 to release the air filled in the internal space of the tire (step S9). Also, with the rotation of the upper spindle 22 blocked, the lower spindle rotation control unit 902 rotates the lower spindle 21 in the direction opposite to the arrow in FIG. 4, so that the plurality of insertion engagement portions 224A disengage from the plurality of lock engagement portions 250A in the circumferential direction, and the lock between the lower spindle 21 and the upper spindle 22 is released (step S10 in FIG. 14). Further, the upper spindle 22 is lifted by the lifting unit 50, and the insertion portion 222 disengages from the internal space S of the lower spindle 21 (step S11 in FIG. 14). Thereafter, the transfer conveyor 8 rises, and the tire T is transferred from the lower spindle 21 to the transfer conveyor 8 and placed on the transfer conveyor 8 again (step S12 in FIG. 14). Then, the tire T is carried out from the tire test position P by the transfer conveyor 8 and the carry-out conveyor 9 (step S13 in FIG. 14), and the marking unit 60 applies a predetermined marking to the tire T. As a result, the uniformity test on the tire T is completed.

[0092] Note that, as described above, the tip of the detected portion 229 has a shape extending in the vertical direction (FIG. 13). Therefore, even when the upper spindle flange 227 is lifted with respect to the base plate 515, the pair of upper spindle rotation phase sensors 516 can detect the detected portion 229. With this configuration, after the test on the tire T is completed as described above, when the upper spindle 22 including the upper spindle flange 227 is arranged again at a specific rotational position, the pair of upper spindle rotation phase sensors 516 can detect the detected portion 229. Therefore, when the pair of upper spindle rotation phase sensors 516 detect the detected portion 229 and the upper spindle lifting control unit 903 controls the upper spindle lifting drive unit 94 to lift the lifting unit 50 by the descending amount H, the four base plate pins of the base plate 515 are fitted into the four hole portions 227A of the upper spindle flange 227, and the rotation of the upper spindle 22 including the upper spindle flange 227 around the reference rotation center axis 2S is blocked. In this state, the lower spindle rotation control unit 902 controls the lower spindle rotation drive unit 93 to rotate the lower spindle 21 by 30 degrees, and then the upper spindle 22 can be lifted with respect to the lower spindle 21 and the upper spindle 22 can be extracted from the internal space S.

[0093] <Regarding the Accuracy Inspection of the Tire Tester> In the tire testing machine 1 as described above, accuracy inspections are regularly performed. In the present embodiment, for each of the ten (M = 10) tires T, uniformity tests are performed ten times (N = 10) in sequence, and finally N×M = 100 pieces of data are obtained. Then, based on a known statistical analysis method from these 100 pieces of data, the range of data variation is calculated, and the measurement accuracy is confirmed when the range of variation is equal to or less than a predetermined threshold value. In the present embodiment, for one tire T, ten uniformity tests are performed while changing the rotational phase between the tire T, the lower spindle 21, and the upper spindle 22. At this time, during the ten tests, the position of one tire T in the front-rear direction is maintained at the tire test position P, so that the above accuracy inspection can be performed in a short time. Hereinafter, the accuracy inspection in such a present embodiment will be described in detail.

[0094] FIG. 18 is a flowchart of the accuracy inspection of the tire testing machine 1 according to the present embodiment. FIG. 19 is a cross-sectional view showing a state where the tire T is detached from the lower spindle 21 in the accuracy inspection of the tire testing machine 1. In the input unit 92 (FIG. 13), a command button for an operator to command the execution of the accuracy inspection is arranged. When the operator presses the command button, the inspection is switched from a normal uniformity test to an accuracy test, and the accuracy inspection command unit 906 starts the execution of the accuracy test.

[0095] When the accuracy test is started, the first tire T is carried into the tire test position P by the loading conveyor 7 and the transfer conveyor 8 in the same manner as in the above-described uniformity test (step S21 in FIG. 18). Next, the lower spindle rotation control unit 902 rotates the lower spindle 21 so as to match the phase (rotation position) of the lower spindle 21 with the phase of the upper spindle 22 while referring to the detection result of the lower spindle rotation phase sensor 95 (step S22). At this time, since the tire T is arranged on the transfer conveyor 8, it does not rotate.

[0096] Next, the tire conveyance control unit 901 lowers the conveyance conveyor 8, and the tire T is transferred from the conveyance conveyor 8 to the lower spindle 21 (step S23 in FIG. 18). Thereafter, pre-test operations for the uniformity test are executed (step S24). Note that the pre-test operations are the same as the operations from step S3 to step S6 in FIG. 14. Next, in the same manner as step S7 in FIG. 14, the first uniformity test for the first tire T is executed (step S25). Next, post-test operations are executed. Note that the post-test operations are the same as the operations from step S8 to step S11 in FIG. 14. When the post-test operations are completed, the upper spindle 22 is disposed at a position spaced above the tire T, while the tire T is supported by the lower spindle 21 via the lower rim 61.

[0097] Next, the accuracy inspection command unit 906 inputs a rotation command signal for the lower spindle 21 to the lower spindle rotation control unit 902. As a result, the lower spindle rotation control unit 902 controls the lower spindle rotation drive unit 93 to rotate the lower spindle 21 by 36 degrees around the reference rotation center axis 2S (step S27 in FIG. 18). Note that the rotation direction of the lower spindle 21 at this time may be the same as the rotation direction of the lower spindle 21 during the uniformity test or the opposite direction. However, during the accuracy inspection executed for one tire T, the rotation direction of the lower spindle 21 in step S27 is set to be the same. Also, in the above description, the lower spindle 21 is shown as being rotated by 36 degrees, but the lower spindle 21 may be rotated by another angle. In this case, it is desirable that the above angle be set so that the phases of the lower spindle 21 and the tire T do not overlap in N (10) tests. Note that in step S27, the tire T supported by the lower spindle 21 also rotates integrally with the lower spindle 21.

[0098] Next, the tire conveyance control unit 901 controls the tire conveyance mechanism 3 to raise the conveyance conveyor 8 (step S28 in FIG. 18). As a result, the tire T is transferred from the lower spindle 21 to the conveyance conveyor 8 (FIG. 19).

[0099] Next, the determination unit 907 (FIG. 13) determines the current number of test times N for the one tire T (step S29 in FIG. 18). Here, when the current number of test times N < 10 (NO in step S29), the processes after step S22 are repeated. On the other hand, when 10 ≤ N (YES in step S29), the conveyor 8 that supports the tire T at step S28 unloads the tire T from the tire test position P (step S30).

[0100] Next, the determination unit 907 determines the current number of tires M (step S31 in FIG. 18). Here, when M < 10 (NO in step S31), for the new tire T, the processes after step S21 are executed. On the other hand, when 10 ≤ M (YES in step S31), the accuracy inspections for the 10 tires T are all completed, and as described above, the variation range is analyzed.

[0101] In addition, when the determination unit 907 determines NO in step S29 for one tire T, next in step S22, the lower spindle rotation control unit 902 rotates the lower spindle 21 so that the phase of the lower spindle 21 matches the phase of the upper spindle 22. In the present embodiment, as described above, the insertion portion 222 of the upper spindle 22 can be inserted into the internal space S of the lower spindle 21. In particular, the phase of the lower spindle 21 is adjusted so that the plurality of upper spindle engaging portions 224 are fitted into the plurality of lock recesses 250B.

[0102] The plurality of engaging protrusions 224AS and the plurality of locking protrusions 250AS are composed of a part (screw serrations) of a screw formed with a predetermined lead around the reference rotation center axis 2S. Therefore, in order to set the interval between the lower rim 61 and the upper rim 62 according to the width of the tire T, the positions of the plurality of upper spindle engaging portions 224 and the plurality of lock recesses 250B in the circumferential direction are uniquely determined. Therefore, when the lower spindle rotation control unit 902 matches the phase of the lower spindle 21 with the phase of the upper spindle 22 in step S22, the lower spindle 21 and the upper spindle 22 will always be locked at the same rotational position in the 10 tests.

[0103] On the other hand, after each test, in step S27, after the lower spindle 21 and the tire T rotate 36 degrees relative to the upper spindle 22, in the next step S22, the phase of the lower spindle 21 matches the phase of the upper spindle 22. Therefore, for each test, the relative rotational positions (phases) of the lower spindle 21, the upper spindle 22, and the tire T are set to be different. Thus, through 10 tests, 10 test data can be obtained while changing the phase of the tire T relative to the spindle 2 by 36 degrees each time. As a result, for each of the 10 tires T, the variation data in the tire testing machine 1 can be efficiently obtained.

[0104] In addition, in FIG. 18, step S22 in the tests after the second time corresponds to the phase adjustment step of the present invention. Here, when the lower spindle 21 is rotated in a predetermined angle (for example, 36 degrees) in one rotation direction in step S27 during the previous test (clockwise rotation), in the next step S22, in order to return the phases of the lower spindle 21 and the upper spindle 22, the lower spindle 21 may be rotated counterclockwise by the predetermined angle. Also, in order to return the phase, the lower spindle 21 may be rotated clockwise by an angle obtained by subtracting the predetermined angle from 360 degrees. When the predetermined angle is less than 180 degrees, in order to reduce the cycle time, it is preferable to adopt the above counterclockwise rotation mode.

[0105] <Accuracy Inspection Method of Tire Testing Machine 1> The accuracy inspection of the tire testing machine 1 described as above includes the following accuracy inspection methods. The accuracy inspection method is an accuracy inspection method of the tire testing machine 1 that rotates the tire T around the rotation center axis CL in a horizontal posture in which the rotation center axis CL of the tire T extends in the vertical direction at a predetermined tire test position P and performs a predetermined test on the tire T. The accuracy inspection method includes at least a preparation step, a loading step, a first delivery step, a tire clamping step, a test step, an upper spindle separation step, a lower spindle rotation step, a second delivery step, a repetition step, and an analysis step.

[0106] In the preparation step, as the tire tester 1, there are provided a lower spindle 21 that supports the lower portion of the tire T in the horizontal posture so that the tire T can rotate around the rotation center axis CL, an upper spindle 22 that supports the upper portion of the tire T in the horizontal posture so that the tire T can rotate around the rotation center axis CL, and a conveying conveyor 8 (tire conveying mechanism 3) that can convey the tire T in the horizontal posture in the horizontal direction so as to pass through the tire test position P.

[0107] In the loading step, one tire T is loaded onto the tire test position P by the conveying conveyor 8.

[0108] In the first delivery step, the conveying conveyor 8 is relatively moved in the vertical direction with respect to the lower spindle 21, and the one tire T is delivered from the conveying conveyor 8 to the lower spindle 21.

[0109] In the tire clamping step, the upper spindle 22 is relatively lowered with respect to the lower spindle 21, and the one tire T is clamped by the lower spindle 21 and the upper spindle 22.

[0110] In the test step, the lower spindle 21, the one tire T, and the upper spindle 22 are integrally rotated, the test is performed on the one tire T, and test data is acquired.

[0111] In the upper spindle separation step, the upper spindle 22 is relatively raised with respect to the lower spindle 21, and the upper spindle 22 is separated from the tire T.

[0112] In the lower spindle rotation step, the lower spindle 21 is relatively rotated with respect to the upper spindle 22 by a predetermined angle.

[0113] In the second delivery step, the conveying conveyor 8 is relatively moved in the vertical direction with respect to the lower spindle 21, and the one tire T is delivered from the lower spindle 21 to the conveying conveyor 8.

[0114] In the repeating process, the first delivery process, the tire clamping process, the test process, the upper spindle separation process, the lower spindle rotation process, and the second delivery process are repeated in order so that the test is performed the preset number of test times on the single tire T.

[0115] And in the analysis process, based on the test data for the number of test times obtained through the repeating process, the accuracy of the tire testing machine 1 is analyzed.

[0116] According to such an accuracy inspection method, every time a test is performed by changing the phase between the tire T and the spindle 2 for one tire T, operations such as carrying the tire T out from the tire test position P and then carrying it back into the tire test position P again, or frequently aligning the axial position of the tire T with the tire test position P do not occur. Therefore, it is possible to reduce the time required for the accuracy inspection of the tire testing machine 1.

[0117] Further, in the present embodiment, the accuracy inspection method further includes a phase adjustment process of aligning the phases of the upper spindle 22 and the lower spindle 21 to a predetermined specific phase before the first delivery process. The repeating process includes repeating the phase adjustment process, the first delivery process, the tire clamping process, the test process, the upper spindle separation process, the lower spindle rotation process, and the second delivery process in order so that the test is performed the preset number of test times on the single tire T.

[0118] According to such an accuracy inspection method, since it becomes possible to perform a plurality of tests on each tire T in a state where the phases of the upper spindle 22 and the lower spindle 21 are aligned, it is possible to analyze the accuracy variation focusing on the phase between the spindle 2 and the tire T. Also, even when it is necessary to align the phases of the upper spindle 22 and the lower spindle 21 in order to set the interval between the upper and lower rims according to the width of the tire T, the accuracy inspection of the tire testing machine 1 can be performed by making the phases of the spindle 2 and the tire T different.

[0119] Further, in the present embodiment, the preparation step includes a first preparation step and a second preparation step. In the first preparation step, as one of the lower spindle 21 and the upper spindle 22, an insertion portion 222 to be inserted into the other spindle different from the one spindle among the lower spindle 21 and the upper spindle 22 is prepared. The insertion portion 222 has a cylindrical shape with an insertion outer peripheral surface 222S that constitutes the outer peripheral surface of the insertion portion 222 and is centered on the rotation center axis CL. In the second preparation step, as the other spindle, a cylindrical spindle inner peripheral surface 21S that defines an opening X facing the insertion portion 222 of the one spindle in the axial direction and an internal space S capable of receiving the insertion portion 222 through the opening X, and at least a part of the spindle inner peripheral surface 21S, and a locking piece 250 (locking portion) capable of locking the insertion portion 222 inserted into the internal space S so as to restrain the one spindle in the axial direction are prepared.

[0120] According to such an accuracy inspection method, by inserting the insertion portion 222 of one spindle into the internal space S of the other spindle and locking the insertion portion 222 with the locking piece 250, the relative position between the lower spindle 21 and the upper spindle 22 can be easily restrained.

[0121] In addition, in the present embodiment, the first preparation step of the preparation step includes preparing, as the one spindle, one having an insertion portion 222 with a plurality of insertion engagement portions 224A and a plurality of insertion recesses 224B. The plurality of insertion engagement portions 224A are a plurality of insertion engagement portions 224A that each extend in the axial direction of the rotation center axis CL and are arranged at intervals in the rotation direction of the tire T, and each constitute a part of the insertion outer peripheral surface 222S. The plurality of insertion engagement portions 224A each include a plurality of engagement protrusions 224AS that each extend along the rotation direction and are arranged adjacent to each other in the axial direction. The plurality of insertion recesses 224B are a plurality of insertion recesses 224B that are each arranged to extend in the axial direction between the insertion engagement portions 224A adjacent to each other in the rotation direction among the plurality of insertion engagement portions 224A, and each constitute a part of the insertion outer peripheral surface 222S. The plurality of insertion recesses 224B each have a shape that is recessed radially inward with respect to the plurality of insertion engagement portions 224A when viewed from the axial direction.

[0122] In the second preparation step of the preparation step, as the other spindle, one having a lock piece 250 with a plurality of lock engagement portions 250A and a plurality of lock recesses 250B is prepared. The plurality of lock engagement portions 250A are a plurality of lock engagement portions 250A that each extend in the axial direction on the inner peripheral surface 21S of the spindle and are arranged at intervals in the rotation direction. The plurality of lock engagement portions 250A each include a plurality of locking protrusions 250AS that each extend along the rotation direction and are arranged adjacent to each other in the axial direction. The plurality of lock recesses 250B are each arranged on the inner peripheral surface 21S of the spindle so as to extend in the axial direction between the lock engagement portions 250A adjacent to each other in the rotation direction among the plurality of lock engagement portions 250A, and each have a shape that is recessed radially outward with respect to the plurality of lock engagement portions 250A when viewed from the axial direction.

[0123] Further, the phase adjustment step includes aligning the phases of the upper spindle 22 and the lower spindle 21 such that a plurality of insertion engagement portions 224A of the one spindle are respectively aligned with the plurality of lock recesses 250B of the other spindle and the plurality of insertion recesses 224B of the one spindle are respectively aligned with the plurality of lock engagement portions 250A of the other spindle when viewed from the axial direction.

[0124] According to such an accuracy inspection method, the relative position in the axial direction between the lower spindle 21 and the upper spindle 22 can be easily set by the plurality of insertion engagement portions 224A and the plurality of insertion recesses 224B of the insertion portion 222 of one spindle, and the plurality of lock engagement portions 250A and the plurality of lock recesses 250B of the lock piece 250 of the other spindle. In particular, since a plurality of engagement protrusions 224AS are arranged adjacent to each other in the axial direction on the insertion engagement portion 224A of the insertion portion 222, and a plurality of locking protrusions 250AS are arranged adjacent to each other in the axial direction on the lock engagement portion 250A of the lock piece 250, it is possible to easily change the interval between the upper rim 62 and the lower rim 61 according to the width of the tire T by making the engagement positions of the protrusions different from each other in the axial direction.

[0125] Also, in the present embodiment, the tire clamping step includes an insertion step, a positioning step, and an air filling step. In the insertion step, the insertion portion 222 of the one spindle is inserted along the axial direction into the internal space S of the other spindle until the plurality of insertion engagement portions 224A face the plurality of lock engagement portions 250A in the rotational direction.

[0126] In the positioning step, the plurality of locking protrusions 250AS of the plurality of locking engagement portions 250A of the other spindle are respectively engaged with the plurality of engagement protrusions 224AS of the plurality of insertion engagement portions 224A of the one spindle, so that the upper spindle 22 and the lower spindle 21 are relatively positioned in the axial direction according to the width of the one tire T. The lower spindle 21 is rotated relative to the upper spindle 22. Further, in the air filling step, air is filled into the one tire T so that the upper spindle 22, the one tire T, and the lower spindle 21 can rotate integrally.

[0127] According to such an accuracy inspection method, after inserting the insertion portion 222 of the upper spindle 22 into the internal space S of the lower spindle 21, the lower spindle 21 is rotated relative to the upper spindle 22, so that the distance between the upper spindle 22 and the lower spindle 21 can be easily fixed.

[0128] Further, in the present embodiment, the preparation step includes preparing, as the one spindle, a plurality of engagement protrusions 224AS of a plurality of insertion engagement portions 224A having a spiral shape centered on the rotation center axis CL so as to incline in one direction in the axial direction as it advances in the rotation direction, and preparing, as the other spindle, a plurality of locking protrusions 250AS of a plurality of locking engagement portions 250A having a spiral shape centered on the rotation center axis CL so as to incline in the one direction as it advances in the rotation direction, and the spiral shape is engageable with the plurality of engagement protrusions 224AS along the rotation direction. The phase adjustment step includes aligning the phases of the plurality of insertion engagement portions 224A of the one spindle and the plurality of locking recesses 250B of the other spindle as viewed from the axial direction so that the upper spindle 22 and the lower spindle 21 are relatively positioned in the axial direction according to the width of the one tire T when the spiral shapes of the plurality of engagement protrusions 224AS and the spiral shapes of the plurality of locking protrusions 250AS engage with each other in the positioning step.

[0129] According to such an accuracy inspection method, in the phase adjustment process, by aligning the phases of the plurality of insertion engagement portions 224A of the one spindle and the plurality of lock recesses 250B of the other spindle, the insertion position of the insertion portion 222 with respect to the internal space S is matched, and the interval between the lower spindle 21 and the upper spindle 22 can be accurately adjusted according to the width of the tire T.

[0130] Also, in the present embodiment, the lower spindle rotation drive unit 93 is provided with a contact surface pressure applied between the plurality of engagement protrusions 224AS and the plurality of locking protrusions 250AS via the upper rim 62 and the lower rim 61 by the air filled in the tire internal space, and the relative rotation of the lower spindle 21 and the upper spindle 22 around the reference rotation center axis 2S is suppressed. In this state, the lower spindle 21 and the upper spindle 22 are integrally rotated.

[0131] According to such a configuration, by utilizing the driving force of the lower spindle rotation drive unit 93 capable of locking the upper spindle 22 and the lower spindle 21, the upper spindle 22 and the lower spindle 21 can be integrally rotated to perform a predetermined test on the tire T.

[0132] Also, in the present embodiment, the plurality of lock engagement portions 250A and the plurality of lock recesses 250B are respectively formed on the piece inner peripheral surface 250S.

[0133] According to such a configuration, since the plurality of lock engagement portions 250A and the plurality of lock recesses 250B are formed on the lock piece 250, it is not necessary to provide the locking protrusions 250AS on the inner peripheral surface 210S of the spindle body 210, and the processing cost of the spindle body 210 can be reduced.

[0134] Furthermore, in the present embodiment, a single lock piece 250 having a ring shape centered on the reference rotation center axis 2S is provided, and the plurality of lock engagement portions 250A and the plurality of lock recesses 250B are respectively formed on the piece inner peripheral surface 250S of the single lock piece 250.

[0135] According to such a configuration, it is possible to improve the positional accuracy of the plurality of locking protrusions 250AS as compared with the case where the lock piece 250 is composed of a plurality of members.

[0136] Further, in the present embodiment, by relatively rotating the insertion portion 222 of the upper spindle 22 with respect to the lock piece 250 provided on the lower spindle 21, the lower spindle 21 and the upper spindle 22 can be locked and the lock can be released. At this time, since the lock piece 250 is disposed between the lower holding flange 210A and the lower spindle main body portion 210B that can be separated from each other, ring-shaped seal members J (FIG. 8) are disposed on the upper surface portion and the lower surface portion of the lock piece 250, respectively. However, compared with other techniques in which the drive mechanism for driving the lock piece 250 is disposed so as to penetrate the spindle main body 210 of the lower spindle 21 in the radial direction, it is possible to simplify the number and structure of the seal members J. When the lower holding flange 210A and the lower spindle main body portion 210B are completely joined after the lock piece 250 is mounted, the above-described seal member J can also be omitted. Further, due to the relative rotation between the lock piece 250 and the insertion portion 222, the lower spindle 21 and the upper spindle 22 are locked and the lock is released. Therefore, compared with other techniques as described above, it is possible to reduce the number of parts of the tire tester 1 and reduce the failure of the tire tester 1.

[0137] Further, in the present embodiment, as described above, the plurality of engagement protrusions 224AS and the plurality of locking protrusions 250AS are formed of a part (threaded serrations) of a screw formed with a predetermined lead about the reference rotation center axis 2S.

[0138] Therefore, not only the relative position in the axial direction between the upper spindle engaging portion 224 of the insertion portion 222 and the lock piece 250, but also the relative position (rotational position) in the circumferential direction between them can adjust the distance between the lower rim 61 and the upper rim 62, enabling a fine rim width setting. In the above screw structure, the plurality of insertion engaging portions 224A and the plurality of lock engaging portions 250A may be arranged along one continuous virtual spiral shape, or may be arranged along a plurality of virtual spiral shapes spaced apart from each other in the axial direction.

[0139] As described above, the accuracy inspection method of the tire tester 1 according to an embodiment of the present invention has been explained. However, the present invention is not limited to these forms, and the following modified embodiments are possible.

[0140] (1) In the above embodiment, the plurality of engaging protrusions 224AS formed on the insertion engaging portion 224A of the upper spindle engaging portion 224 and the plurality of locking protrusions 250AS formed on the lock engaging portion 250A of the lock piece 250 have been described based on the mode of being a part (screw serrations) of a screw formed with a predetermined lead around the reference rotation center axis 2S. However, the present invention is not limited to this. FIG. 20 is a side view of a state in which the upper rim 62 is supported by the upper spindle 22 of the tire tester according to a modified embodiment of the present invention. FIG. 21 is a side cross-sectional view of the lock piece 250M of the tire tester according to this modified embodiment.

[0141] In this modified embodiment, the plurality of engaging protrusions 224AS are arranged to extend in a direction (horizontal direction) orthogonal to the axial direction. Specifically, both the engaging protrusions 224AS formed on the insertion engaging portion 224A of the upper spindle engaging portion 224 and the locking protrusions 250AS formed on the lock engaging portion 250A of the lock piece 250 extend in a direction orthogonal to the reference rotation center axis 2S (ordinary serrations).

[0142] In such a configuration, as in the previous embodiment, it is not possible to adjust the distance between the lower rim 61 and the upper rim 62 according to the relative position (rotational position) in the circumferential direction between the upper spindle engaging portion 224 and the lock piece 250. However, it is possible to adjust the distance between the lower rim 61 and the upper rim 62 based on the relative position in the axial direction between them.

[0143] Further, in this modified embodiment, since the engaging protrusion 224AS formed on the insertion engaging portion 224A of the upper spindle engaging portion 224 and the locking protrusion 250AS formed on the locking engaging portion 250A of the lock piece 250 both extend in a direction orthogonal to the reference rotation center axis 2S, when the tire inner space is filled with air, the axial forces applied to the lower spindle 21 and the upper spindle 22 can be stably received by the locking protrusion 250AS and the engaging protrusion 224AS.

[0144] (2) Also, in the above embodiment, the upper spindle 22 has the insertion portion 222 and the lower spindle 21 has the cylindrical inner space S. However, a structure in which the upper and lower parts of FIG. 8 are reversed, that is, an embodiment in which the upper spindle 22 has the cylindrical inner space S and the lower spindle 21 has the insertion portion 222 may also be used. Note that, as in the above embodiment, when the cylindrical inner space S is formed in the lower spindle 21 and the cylindrical insertion portion 222 is formed in the upper spindle 22, the length of the lower spindle 21 in the vertical direction becomes shorter. For this reason, it is possible to lower the height of the transfer conveyor 8 that transfers the lower rim 61 to and from the lower spindle 21, and it is also possible to similarly set the height of the transfer path of the tire transfer mechanism 3 to be low.

[0145] (3) Also, in the above embodiment, the lower spindle 21 has the lock piece 250 attached to the spindle body 210, and the plurality of lock engaging portions 250A and the plurality of lock recesses 250B are formed in the lock piece 250. However, the lower spindle 21 may not have the lock piece 250, and the plurality of lock engaging portions 250A and the plurality of lock recesses 250B may be directly formed on the inner peripheral surface 210S of the main body of the spindle body 210.

[0146] (4) Also, in the above-described embodiment, the engagement between the lower spindle 21 and the upper spindle 22 has been described in a manner in which the rotation of the upper spindle 22 is blocked at a specific rotational position detected by the pair of upper spindle rotation phase sensors 516 with the upper spindle flange 227 included in the upper spindle 22. However, the present invention is not limited to this. The upper spindle 22 may be arranged at an arbitrary rotational position around the reference rotation center axis 2S, and its rotation may be blocked, and the engagement between the lower spindle 21 and the upper spindle 22 may be performed. That is, instead of the pair of upper spindle rotation phase sensors 516 described above, an encoder (not shown) arranged on the rotation axis of the upper spindle 22 as a rotation detection unit detects the rotational position of a specific portion of the upper spindle 22 around the reference rotation center axis 2S. Further, when the rotation of the upper spindle 22 is stopped, a brake mechanism or the like that mechanically contacts the upper spindle 22 blocks the rotation of the upper spindle 22 as a rotation blocking unit. Then, the lower spindle rotation drive unit 93 rotates the lower spindle 21 around the reference rotation center axis 2S according to the detection result of the encoder such that a plurality of insertion engagement portions 224A of the upper spindle 22 respectively match a plurality of lock recesses 250B of the lower spindle 21 and a plurality of insertion recesses 224B of the upper spindle 22 respectively match a plurality of lock engagement portions 250A of the lower spindle 21 in a state where the rotation of the upper spindle 22 is blocked by the rotation blocking unit.

[0147] According to such a configuration, it is possible to easily perform alignment in the rotational direction between the lock piece 250 of the lower spindle 21 and the upper spindle engagement portion 224 of the upper spindle 22 in order to adjust the rim width without stopping the upper spindle 22 at a specific rotational position.

[0148] Furthermore, in this case, the upper spindle lifting drive unit 94 can relatively insert the insertion portion 222 of the upper spindle 22 to a specific position in the internal space S of the lower spindle 21 in a state where the rotation of the upper spindle 22 is blocked by the rotation blocking portion and the plurality of insertion engaging portions 224A respectively match the plurality of lock recesses 250B and the plurality of insertion recesses 224B respectively match the plurality of lock engaging portions 250A. Also, the lower spindle rotation drive unit 93 can rotate the lower spindle 21 around the reference rotation center axis 2S so that the plurality of engaging protrusions 224AS of the plurality of insertion engaging portions 224A and the plurality of locking protrusions 250AS of the plurality of lock engaging portions 250A engage with each other in a state where the rotation of the upper spindle 22 is blocked by the rotation blocking portion and the insertion portion 222 is inserted to the specific position in the internal space S.

[0149] According to such a configuration, without stopping the upper spindle 22 at a specific rotational position, the insertion portion 222 of the upper spindle 22 can be easily inserted into the internal space S of the lower spindle 21, and the upper spindle engaging portion 224 and the lock piece 250 can be engaged with each other. For this reason, since the upper spindle 22 and the lower spindle 21 can be relatively moved in order in the axial direction and the rotational direction to lock both spindles, it is possible to prevent the upper spindle 22 and the lower spindle 21 from rotating together with each other during locking. Also, in this case as well, in a state where the rotation of the lower spindle 21 is blocked by the same structure as described above, the upper spindle engaging portion 224 and the lock piece 250 may be engaged with each other by the rotation of the upper spindle 22. Further, since the insertion portion 222 is inserted into the internal space S, the lower spindle 21 may be lifted with respect to the upper spindle 22. That is, in the present invention, "one spindle" and "the other spindle" may be selectively set from the lower spindle 21 and the upper spindle 22, and similarly, "the first spindle" and "the second spindle" may be selectively set, that is, set in the reverse of the above-described embodiment.

Explanation of Reference Numerals

[0150] 1 Tire tester 1S main body frame 2 Spindle 21 Lower spindle (the other spindle, second spindle) 210 Spindle body 210S Inner peripheral surface of the main body 21S Inner peripheral surface of the spindle 22 Upper spindle (one spindle, first spindle) 222 Insertion part 222S Outer peripheral surface of the insertion 223 Guide piece 224 Upper spindle engaging part 224A Insertion engaging part 224AS Engaging protrusion 224B Insertion recess 250 Lock piece (locking part) 250A Lock engaging part 250AS Locking protrusion 250B Lock recess 250S Inner peripheral surface of the piece 2S Reference rotation center axis 3 Tire conveying mechanism 4 Rotating drum 4A Simulated road surface 50 Lifting unit 61 Lower rim 62 Upper rim 90 Control unit 901 Tire conveying control unit 902 Lower spindle rotation control unit 903 Upper spindle lifting control unit 904 Air supply control unit 905 Memory unit 906 Precision inspection command unit 907 Judgment unit 93 Lower spindle rotation drive unit 94 Upper spindle lifting drive unit 95 Lower spindle rotation phase sensor CL Tire rotation center axis P Tire test position S Internal space T Tire

Claims

1. A method for inspecting the accuracy of a tire testing machine that rotates a tire in a horizontal posture in which the rotation center axis of the tire extends in the vertical direction at a predetermined tire test position and performs a predetermined test on the tire, comprising: A preparation step of preparing, as the tire testing machine, a conveying unit capable of horizontally conveying the tire in the horizontal posture so as to pass through the tire test position, a lower spindle that supports a lower portion of the tire in the horizontal posture at the tire test position so that the tire can rotate around the rotation center axis, and an upper spindle that supports an upper portion of the tire in the horizontal posture at the tire test position; A loading step of loading one tire into the tire test position by the conveying unit; A first delivery step of relatively moving the conveying unit in the vertical direction with respect to the lower spindle and delivering the one tire from the conveying unit to the lower spindle; A tire clamping step of relatively lowering the upper spindle with respect to the lower spindle and clamping the one tire by the lower spindle and the upper spindle; A test step of integrally rotating the lower spindle, the one tire, and the upper spindle, performing the test on the one tire, and acquiring test data; An upper spindle separation step of relatively raising the upper spindle with respect to the lower spindle and separating the upper spindle from the tire; A lower spindle rotation step of relatively rotating the lower spindle by a predetermined angular amount with respect to the upper spindle; A second delivery step of relatively moving the conveying unit in the vertical direction with respect to the lower spindle and delivering the one tire from the lower spindle to the conveying unit; A repeating step of sequentially repeating the first delivery step, the tire clamping step, the test step, the upper spindle separation step, the lower spindle rotation step, and the second delivery step so as to perform the test a preset number of times on the one tire; An analysis step of analyzing the accuracy of the tire testing machine based on the test data for the number of tests obtained through the repeating step; A method for inspecting the accuracy of a tire testing machine, comprising the above steps.

2. The method further comprises a phase adjustment step of adjusting the phases of the upper spindle and the lower spindle to a predetermined specific phase before the first delivery step. The repeating step includes repeating the phase adjustment step, the first delivery step, the tire clamping step, the test step, the upper spindle separation step, the lower spindle rotation step, and the second delivery step in this order so that the test is performed the preset number of test times on the one tire. A method for inspecting the accuracy of a tire testing machine according to claim 1.

3. The preparation step includes: preparing, as one of the lower spindle and the upper spindle, a cylindrical insertion portion having an insertion outer peripheral surface that constitutes an outer peripheral surface of the insertion portion and is inserted into the other spindle different from the one spindle of the lower spindle and the upper spindle, the insertion portion being centered on the rotation center axis; preparing, as the other spindle, a cylindrical spindle inner peripheral surface that defines an opening facing the insertion portion of the one spindle in the axial direction of the rotation center axis and an internal space capable of receiving the insertion portion through the opening, and a lock portion that constitutes at least a part of the spindle inner peripheral surface and is capable of locking the insertion portion inserted into the internal space so as to restrain the one spindle in the axial direction. A method for inspecting the accuracy of a tire testing machine according to claim 2, including the above.

4. The preparation step includes: as the one spindle, the insertion portion is a plurality of insertion engagement portions that extend in the axial direction of the rotation center axis and are arranged at intervals from each other in the rotation direction of the tire, each of which constitutes a part of the insertion outer peripheral surface, and each of the plurality of insertion engagement portions includes a plurality of engagement protrusions that extend along the rotation direction and are arranged adjacent to each other in the axial direction; a plurality of insertion recesses that are arranged to extend in the axial direction between the insertion engagement portions adjacent to each other in the rotation direction among the plurality of insertion engagement portions, each of which constitutes a part of the insertion outer peripheral surface, and each of the plurality of insertion recesses has a shape that is recessed radially inward with respect to the plurality of insertion engagement portions when viewed from the axial direction; preparing a spindle having the above; as the other spindle, the lock portion A plurality of locking engagement portions that extend in the axial direction on the inner peripheral surface of the spindle and are arranged at intervals from each other in the rotational direction, each of the plurality of locking engagement portions including a plurality of locking protrusions that extend along the rotational direction and are arranged adjacent to each other in the axial direction. A plurality of locking recesses that are respectively arranged on the inner peripheral surface of the spindle so as to extend in the axial direction between the locking engagement portions that are adjacent to each other in the rotational direction among the plurality of locking engagement portions, and each have a shape that is recessed radially outward with respect to the plurality of locking engagement portions when viewed from the axial direction. Preparing an object having the above, including. The phase adjustment step includes aligning the phases of the upper spindle and the lower spindle so that, when viewed from the axial direction, the plurality of insertion engagement portions of the one spindle respectively coincide with the plurality of locking recesses of the other spindle and the plurality of insertion recesses of the one spindle respectively coincide with the plurality of locking engagement portions of the other spindle, and an insertable state is achieved. The method for inspecting the accuracy of a tire testing machine according to claim 3.

5. The tire clamping step includes An insertion step of inserting the insertion portion of the one spindle along the axial direction into the internal space of the other spindle until the plurality of insertion engagement portions face the plurality of locking engagement portions in the rotational direction respectively. A positioning step of relatively rotating the lower spindle with respect to the upper spindle so that the plurality of locking protrusions of the plurality of locking engagement portions of the other spindle respectively engage with the plurality of engagement protrusions of the plurality of insertion engagement portions of the one spindle, and positioning the upper spindle and the lower spindle relatively in the axial direction according to the width of the one tire. An air filling step of filling air into the one tire so that the upper spindle, the one tire, and the lower spindle can rotate integrally. The method for inspecting the accuracy of a tire testing machine according to claim 4, including.

6. The preparation step includes As the one spindle, preparing one having a spiral shape centered on the rotation center axis such that the plurality of engagement protrusions of the plurality of insertion engagement portions incline in one direction in the axial direction as they advance in the rotational direction. As the other spindle, prepare one having a spiral shape centered on the rotation center axis such that the plurality of locking protrusions of the plurality of lock engagement portions incline in the one direction as they proceed in the rotation direction, and having a spiral shape engageable with the plurality of engagement protrusions along the rotation direction. including The phase adjustment step includes aligning the phases of the plurality of insertion engagement portions of one spindle and the plurality of lock recesses of the other spindle as viewed from the axial direction so that the upper spindle and the lower spindle are relatively positioned in the axial direction according to the width of the one tire by the spiral shape of the plurality of engagement protrusions and the spiral shape of the plurality of locking protrusions engaging with each other in the positioning step. The method for inspecting the accuracy of a tire testing machine according to claim 5.

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