JP2011220964A - Tire side face failure detection method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire side face failure detection device capable of reducing examination preparation time even in a case a size of the tire to be examined is changed.SOLUTION: When taking a photograph of a side face of a tire 12 from the front using a video camera 20, an end 18A of fiber optic 18 is brought to a position close to the video camera 20 so that a specular reflection is within a photographing range on one end of the photographing range. Thereby, a specular reflection of a projected beam light is generated in a reference high luminance part, and a luminance in other high luminance part having a local slight swelling on a side face of the tire 12 becomes higher than that of a surrounding area. Thus, a failure in the side face of the tire 12 is detected by a personal computer 24 based on the distance from the reference high luminance part to the other high luminance part in a direction of a circumference of the tire, and the luminance of other high luminance parts.

Description

  The present invention relates to a tire side failure detection method and apparatus for detecting a failure on a side surface of a rotating tire in a tire durability test.

  In the tire durability test, a durability test is performed while running a test tire on the outer periphery of the drum. When a failure occurs in the tire, the failure is detected and the test is terminated. Conventionally, when detecting a failure of a rotating tire in a tire endurance test, a touch sensor has been installed at a portion where the failure is likely to occur, such as a side surface of the tire. Further, as a technique for improving the touch sensor, there has been proposed an apparatus (for example, refer to Patent Document 1) that detects a tire failure when a tire surface that has expanded due to a tire failure comes into contact with a detection body.

JP 2005-55380 A

  However, the apparatus of Patent Document 1 uses a U-shaped detecting body that can be bent and deformed from one bead part side to the other bead part side along the outer edge of the tire. For this reason, when the tire to be tested is changed, the detector needs to be deformed along the outer edge of the tire changed by the operator. As a result, the setting of the apparatus becomes complicated and it takes time to prepare for the test.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a tire side surface failure detection device that can shorten the test preparation time even when the size of the tire to be tested is changed.

  In the tire side surface failure detection method according to the first aspect of the present invention, the brightness due to regular reflection at a reference position without tilting along the circumferential direction of the tire side surface is photographed by projecting light from the light source of the tire. Check whether there is a reference high-intensity part higher than a predetermined value, and other high-intensity parts having a luminance higher than the predetermined value at a radial position corresponding to the reference position and other than the reference position, When it is confirmed that there is another high-luminance part, the distance in the tire circumferential direction between the reference high-luminance part and the other high-luminance part in the captured image and the luminance of the other high-luminance part From the above, a failure on the side surface is detected.

  In the tire side surface failure detection method according to claim 1, when photographing the side surface of the tire, the brightness due to regular reflection at a reference position without inclination along the circumferential direction of the side surface of the tire by the light projected from the light source is a predetermined value. It is confirmed whether or not there is a higher reference high-luminance part and another high-luminance part having a higher luminance than a predetermined value at a radial position corresponding to the reference position and other than the reference position. And when it is confirmed that there is another high-luminance part, from the distance in the tire circumferential direction between the reference high-luminance part and the other high-luminance part in the captured image, and the luminance of the other high-luminance part , Detect side failure. For this reason, even if the size of the tire to be tested is changed, it is only necessary to photograph the side surface of the tire, so that it can be easily set according to the size of the tire. As a result, the test preparation time can be shortened.

  According to a second aspect of the present invention, in the tire side surface failure detection method according to the first aspect of the present invention, the entire circumference of the side surface of the tire is photographed by dividing it into N times, and the rotation period of the tire is set to T and n. In the case of an integer, the photographing interval is nT ± (T / N).

  In the tire side surface failure detection method according to claim 2, when the entire circumference of the tire side surface is photographed by dividing it into N times, and the tire rotation cycle is T and n is a positive integer, the photographing interval is nT ±. (T / N), it is possible to obtain a photographed image of the entire circumference of the side surface of the tire that rotates at high speed using a general photographing apparatus that is not a high-speed compatible photographing apparatus as in the case of a high-speed compatible photographing apparatus. it can.

  According to a third aspect of the present invention, in the tire side surface failure detection method according to the second aspect, the light source is turned on in synchronization with the photographing interval.

  In the tire side surface failure detection method according to the third aspect, since the light source is turned on in synchronization with the photographing interval, the power consumption of the light source can be suppressed.

  According to a fourth aspect of the present invention, in the tire side surface failure detecting method according to any one of the first to third aspects, the projection light from the light source is guided to the vicinity of the side surface of the tire.

  In the tire side surface failure detection method according to the fourth aspect, since the projection light from the light source is guided to the vicinity of the side surface of the tire, it is possible to prevent the light source from being damaged when the tire bursts.

  According to a fifth aspect of the present invention, in the tire side failure detection method according to any one of the first to fourth aspects, the tire is stopped when the side failure is detected.

  In the tire side surface failure detection method according to the fifth aspect, since the tire is stopped when the side surface failure is detected, the tire can be prevented from bursting.

  The tire side surface failure detection device according to claim 6 is a drive device that rolls a tire, at least one imaging device that images the side surface of the tire, and a light source that projects projection light onto the side surface of the tire. A reference high-intensity part whose luminance by regular reflection at a reference position without inclination along the circumferential direction of the side surface of the tire from the image data of the side surface imaged by the imaging device is higher than a predetermined value, and the reference position When it is confirmed that there is another high-luminance part other than the reference position and having a brightness higher than the predetermined value, and it is confirmed that the other high-luminance part exists. Image processing means for detecting a failure on the side surface from the distance in the tire circumferential direction between the reference high-intensity part and the other high-intensity part in the captured image and the luminance of the other high-intensity part; With That.

  In the tire side surface failure detection device according to the sixth aspect, the side surface of the tire rolling by the driving device is photographed by at least one photographing device. At this time, the projection light from the light source is projected onto the side surface of the tire. Further, by the image processing means, a reference high-intensity portion whose luminance by regular reflection at a reference position without inclination along the circumferential direction of the tire side surface is higher than a predetermined value, a radial position corresponding to the reference position, and a reference position It is checked whether there is any other high-luminance part whose luminance is higher than a predetermined value. And when it is confirmed that there is another high-luminance part, from the distance in the tire circumferential direction between the reference high-luminance part and the other high-luminance part in the captured image, and the luminance of the other high-luminance part , Detect side failure. For this reason, even when the size of the tire to be tested is changed, the photographing device and the light source need only be arranged at a position where the side surface of the tire can be photographed, so that it can be easily set according to the tire size. As a result, the test preparation time can be shortened.

  The invention according to claim 7 is the tire side failure detection device according to claim 6, wherein the imaging device shoots the entire circumference of the side surface of the tire in N times, and sets the rotation cycle of the tire. When T and n are positive integers, the photographing interval is nT ± (T / N).

  In the tire side surface failure detection device according to claim 7, when the entire circumference of the tire side surface is divided into N times by the imaging device and the rotation period of the tire is T and n is a positive integer, the imaging interval is taken. Is set to nT ± (T / N), so that the image of the entire circumference of the side surface of the tire rotating at high speed is obtained using a general imaging device that is not a high-speed imaging device, as in a high-speed imaging device. Obtainable.

  According to an eighth aspect of the present invention, in the tire side surface failure detection device according to the seventh aspect, the light source is turned on in synchronization with the photographing interval.

  In the tire side surface failure detection device according to the eighth aspect, since the light source is turned on in synchronization with the photographing interval, the power consumption of the light source can be suppressed.

  A ninth aspect of the present invention is the tire side failure detection device according to any one of the sixth to eighth aspects, further comprising light guide means for guiding the projection light of the light source to the vicinity of the tire.

  In the tire side surface failure detection device according to the ninth aspect, since the light guide means guides the light emitted from the light source to the vicinity of the side surface of the tire, it is possible to prevent the light source from being damaged when the tire bursts.

  According to a tenth aspect of the present invention, in the tire side failure detection device according to any one of the sixth to ninth aspects, the driving device stops when the image processing means detects the side failure.

  In the tire side failure detection apparatus according to the tenth aspect, the driving device stops when the image processing means detects a side failure. For this reason, when the failure of the side surface is detected, the tire is stopped and the tire can be prevented from bursting.

  As described above, the tire side surface failure detection method according to the first aspect of the present invention can shorten the test preparation time even when the size of the tire to be tested is changed.

  The tire side surface failure detection method of the present invention described in claim 2 can use a general photographing apparatus.

  The tire side surface failure detection method according to the third aspect of the present invention can suppress the power consumption of the light source.

  The tire side surface failure detection method of the present invention according to claim 4 can prevent the light source from being damaged.

  The tire side surface failure detection method of the present invention according to claim 5 can prevent the tire from bursting.

  The tire side surface failure detection apparatus according to the sixth aspect of the present invention can shorten the test preparation time even when the size of the tire to be tested is changed.

  The tire side surface failure detection device of the present invention according to claim 7 can use a general photographing device.

  The tire side surface failure detection apparatus of the present invention according to claim 8 can suppress the power consumption of the light source.

  The tire side surface failure detection apparatus according to the ninth aspect of the present invention can prevent the light source from being damaged.

  The tire side surface failure detection device of the present invention according to claim 10 can prevent the tire from bursting.

1 is a block diagram showing a tire side surface failure detection apparatus according to an embodiment of the present invention. It is explanatory drawing which shows the state which is image | photographing the pneumatic tire which rolls with the tire side surface failure detection apparatus which concerns on one Embodiment of this invention. It is a mimetic diagram showing the principle of the tire side surface failure detection device concerning one embodiment of the present invention. It is the schematic which shows the picked-up image of a comparative example. It is the schematic which shows the picked-up image of the tire side surface fault detection apparatus which concerns on one Embodiment of this invention. It is a graph which shows the relationship between the reference | standard high-intensity site | part and the other high-intensity site | part in the tire side surface failure detection apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the picked-up image of the tire side surface fault detection apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the picked-up image of the tire side surface fault detection apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the picked-up image of the tire side surface fault detection apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the picked-up image of the tire side surface fault detection apparatus which concerns on one Embodiment of this invention.

  Hereinafter, a tire side surface failure detection apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a tire side surface failure detection device 10 according to the present embodiment includes a drive device 11 for rolling a tire 12 and a bead portion 12A of a sidewall portion 12S as a side surface of the rolling tire 12. Are provided with a lamp 16 as an example of a light source for generating halation. The lamp 16 is a strobe lamp that blinks at predetermined intervals when the power supply 17 is turned on / off. Further, an optical fiber 18 as an example of a light guide means is provided between the lamp 16 and the tire 12. For this reason, the projection light from the lamp 16 is guided to the vicinity of the sidewall portion 12S of the tire 12 via the optical fiber 18, and is projected from the tip 18A of the optical fiber 18 to the sidewall portion 12S. For example, a fire strobe (trade name: CF-15) manufactured by Nissin Electronics is used as the lamp 16 and the optical fiber 18.

  Therefore, since a strobe lamp blinking at a predetermined interval is used as the lamp 16, power consumption can be suppressed as compared with a device that always lights the lamp. In addition, by using the optical fiber 18, the lamp 16 can be disposed at a position away from the tire 12. For this reason, when the tire 12 bursts, the lamp 16 can be prevented from being damaged by the fragments of the tire 12.

  Further, a video camera 20 as an example of a photographing device is disposed at a position where the sidewall portion 12S of the tire 12 can be photographed. For example, a Sony video camera (trade name: XCD-U100) is used as the video camera 20.

  The video camera 20 (product name: XCD-U100) has a maximum shooting speed of 15 frames per second. If the trigger mode is used, shooting can be performed at intervals of the trigger signal, and up to 8 frames can be stored in the video camera built-in memory. It is possible. In addition, when the captured image is directly transferred to the personal computer 24 as an example of the image processing means without using the video camera built-in memory, and the shootable speed is reduced by this direct transfer, the tire rotation cycle to be added to the shoot is added. It is possible to adjust the multiple to twice or more. Further, in order to shorten the photographing time, when a fraction such as 1/2 is used as a multiple of the tire rotation cycle to be added, photographing images need to be rearranged in accordance with the rotation angle.

  In the present embodiment, the video camera 20 is connected to a personal computer 24 as an example of image processing means by a cable 22 compliant with, for example, IEEE1394, and control of shooting conditions between the video camera 20 and the personal computer 24 is performed. The captured image is transferred.

  The video camera 20 is connected to a camera adapter 28 (for example, Sony CD-700) by a camera cable 26. The camera adapter 28 is connected to the power supply 17 by a BNC cable 30 so that the lamp 16 is lit in synchronization with the shooting interval of the video camera 20. Further, the driving device 11 is connected to a personal computer 24, and the driving device 11 is activated or stopped by a control signal from the personal computer 24.

  As shown in FIG. 2, the tire 12 is mounted on the rotating shaft 11A of the driving device 11 with the rim incorporated therein, and is rotatable in the direction of arrow A in FIG. Further, the video camera 20 is fixed to the lower surface 34A of the cover 34 that covers the driving device 11, and the side wall portion 12S of the tire 12 can be photographed. Note that in the captured image of the video camera 20, the arrow UP direction is at the top of the screen. Further, the ground contact surface 12B of the tire 12 is in contact with a test endless belt 36, and the endless belt 36 is rotated in the direction of arrow B in FIG.

(Principle of tire side failure detection)
As shown in FIG. 3, when the shooting range (shooting angle) of the video camera 20 is θ1 (for example, 24 degrees) and the shooting distance is Q1 (for example, 100 mm), the tip 18A of the optical fiber 18 is connected to the video camera. By separating the distance M1 from the distance M1 (about 42.5 mm), the incident angle θ2 and the reflection angle θ3 at the reference position without inclination along the circumferential direction of the bead portion 12A as an example of the side surface of the tire 12 at one end of the photographing range. Are equal (for example, 12 degrees) and regularly reflected (reference high-intensity part P1).

  At this time, in order for the projection light from the tip 18A of the optical fiber 18 to be specularly reflected at the center of the image (other reference high-intensity part P2), the inclination along the circumferential direction of the surface due to the bulging of the bead part 12A ( α2) needs about 11.5 degrees. In addition, in order for the projection light from the tip 18A of the optical fiber 18 to be regularly reflected (other reference high-intensity part P3) at the other end of the other imaging range, along the circumferential direction of the surface due to the swelling of the bead portion 12A or the like. An inclination (α3) of about 22.3 (24/2 + 10.3) degrees is required.

  That is, with the increase in the inclination along the circumferential direction of the surface of the bead part 12A due to the local swelling of the bead part 12A of the tire 12, the distance from the reference high-intensity part (P1) without inclination is longer (the distance is longer). ) Regular reflection at the position.

  When the video camera 20 is used to photograph the sidewall portion 12S of the tire 12 from the front, if the tip 18A of the optical fiber 18 is arranged away from the video camera 20 to a position where the regular reflection light does not enter the photographing range, FIG. As shown in FIG. 4, the local minute bulge (F1) indicated by the broken-line square is not clear because there is only a thin shadow caused by the obliquely irradiated light.

  On the other hand, in this embodiment, when the video camera 20 captures the sidewall portion 12S of the tire 12 from the front, as shown in FIG. 5, the specularly reflected light enters the imaging range at one end of the imaging range. The tip 18A of the optical fiber 18 is brought close to the video camera 20 so that the position (reference high luminance part P1) enters. As a result, the specularly reflected light projected from the tip 18A of the optical fiber 18 is symmetric with respect to the vertical axis (H) with respect to the imaging surface (reference high luminance part P1) and the incident angle (θ2) and reflection angle as shown in FIG. (Θ3) occurs in the same direction. On the other hand, the side surface of the bead portion 12A of the tire 12 is black and has a smooth surface, and therefore diffuse reflection occurs in the vicinity of a local minute bulge (the other high-luminance portions P2 and P3). As a result, the brightness of the local minute bulge (the other high brightness portions P2 and P3) is higher than the brightness of the surrounding area.

  That is, in a local minute bulge in the tire durability test (other high-luminance parts P2, P3), the bulge (other high-luminance parts P2, P3) from the reference high-luminance part (P1) without inclination (flat). ) Gradually increases toward), and decreases from the middle of the bulge toward the top. For this reason, the brightness | luminance of other high-intensity parts (P2, P3) becomes as shown in FIG.

  As a result, as shown in FIG. 6, the luminance (K1) of the reference high luminance portion (P1) of the bead portion 12A and the luminance (K2) of other high luminance portions (P2), for example, from the threshold (K0). The light amount (S1) of specular reflection light at the reference high luminance part (P1) and the light quantity (S2) of specular reflection light at the other high luminance part (P2) increase.

  For this reason, the personal computer 24 checks whether or not there is another high-luminance part (P2) with respect to the reference high-luminance part (P1), and confirms that there is another high-luminance part (P2). Includes the distance (L1) in the tire circumferential direction between the reference high-intensity part (P1) and the other high-intensity part (P2) in the captured image, and the luminance (S2) of the other high-intensity part (P2). The failure of the bead portion 12A of the tire 12 can be detected.

(Synchronous and delayed shooting during tire rotation)
The rotational speed during the tire durability test is, for example, about 400 rpm under the condition of 80 km / h. Therefore, as shown in FIG. 3, in order to photograph the entire region of the sidewall portion 12 </ b> S of the tire 12 with the video camera 20 in which the photographing range is an angle θ <b> 1 (for example, 24 degrees), the tire 12 is rotated once. 24 pictures will be taken. Therefore, the shooting interval is about 0.00625 = (60/400) × (1/24) seconds, and a high-speed video camera is required.

  On the other hand, in the present embodiment, one image is taken with one rotation of the tire 12, and the entire region of the sidewall portion 12S is taken with the tire 12 rotating 24 times. This is because the tire endurance test takes a long time, so there is no significant problem in detection accuracy even if the tire 12 is rotated 24 times and the entire area of the sidewall portion 12S is photographed.

  That is, in this embodiment, when the rotation period of the tire 12 is T and n is a positive integer, the shooting interval is T ± (T / N). Specifically, the imaging interval is set to about 0.15625 seconds≈ (60/400) × (1 + 1/24) by adding about 0.015 seconds, which is one time the rotation period T of the tire 12. As a result, the shooting interval becomes 6.4 frames per second.

  Therefore, with respect to the first image shown in FIG. 7, the second image shown in FIG. 8 is an image after 1 + 1/24 rotation, and the third image shown in FIG. 9 is an image after 2 + 2/24 rotation. It is an image. Thus, in a tire durability test with a long test time, there is no significant difference in tire changes even after 1 + 1/24 rotations or after 2 + 2/24 rotations. In addition, the arrow A of FIGS. 7-9 has shown the rotation direction of the tire 12 on an image.

  Therefore, in the present embodiment, a high-speed video camera is not required for photographing the entire region of the sidewall portion 12S of the tire 12.

(Test example)
A pneumatic truck bus tire 295 / 75R22.5 was used as the test tire 12, and a normal rim was incorporated into the tire 12 to obtain a normal internal pressure. The tire 12 was attached to a test apparatus that rotates the tire 12, and a normal load was applied. Here, “regular rim” refers to the standard rim in the applicable size specified in the 2009 edition YEAR BOOK issued by JATMA, and “regular load” and “regular internal pressure” are similarly issued by JATMA. The maximum load in the applicable size and ply rating defined in the 2009 YEAR BOOK and the air pressure with respect to the maximum load. When the TRA standard or ETRTO standard is applied at the place of use or manufacturing, the respective standards are followed.

  The tire 12 was rolled so as to travel at a speed of 80 km / h. At this time, the rotation speed is around 430 rpm. Further, the projection light from the tip 18 </ b> A of the optical fiber 18 was projected onto the sidewall portion 12 </ b> S of the tire 12 and photographed with the video camera 20. This captured image is shown in FIG. In addition, the recording data captured by the video camera 20 is processed by the personal computer 24. Then, based on the change in luminance shown in FIG. 6, it is confirmed whether or not the bead portion 12A of the tire 12 swells, for example, whether there is another high-luminance part (P2), and other high-luminance parts (P2). When it is confirmed that there is a tire, the distance (L1) in the tire circumferential direction between the reference high-intensity part (P1) and the other high-intensity part (P2) in the captured image, and the other high-intensity part (P2) ) (S2), when both L1 and S2 are out of the range of the predetermined value, a failure of the bead portion 12A of the tire 12 is detected, and the driving device 11 is stopped. This is because there are fine irregularities in the tire circumferential direction on the surface of the tire, and even if a high luminance part appears, if it is too close to the reference high luminance part, the original tire irregularity The possibility of being affected is high. Therefore, in addition to S2, L1 also determines that it is a failure when it exceeds a predetermined value, thereby reducing the proportion of cases where a portion that is not a failure is determined to be a failure and increasing the inspection process speed. This is to make it possible.

(Action / Effect)
As described above, in this embodiment, even when the size of the tire 12 to be tested is changed, the video camera 20 and the tip 18A of the optical fiber 18 may be disposed at a position where the sidewall portion 12S of the tire 12 can be photographed. It can be easily set according to the size of the tire 12. As a result, the test preparation time can be shortened.

  Further, in the present embodiment, in order to photograph the entire region of the sidewall portion 12S of the tire 12, the photographing interval of the video camera 20 is set to T ± (T / T when the tire rotation period is T and n is a positive integer. N), the shooting interval is long. As a result, it is possible to obtain a photographed image of one rotation of the tire 12 similar to that of a high-speed imaging device using a general video camera that is not a high-speed video camera. As a result, the cost of the tire sidewall failure detection device 10 can be reduced.

  In this embodiment, since the lamp 16 is lit in synchronization with the shooting interval of the video camera 20, power consumption and temperature rise of the lamp 16 can be suppressed.

  In the present embodiment, the optical fiber 18 that guides the projection light of the lamp 16 to the sidewall portion 12 </ b> S of the tire 12 is provided between the lamp 16 and the tire 12. For this reason, the lamp 16 can be disposed at a position away from the tire 12. As a result, it is possible to prevent the lamp 16 from being damaged when the tire 12 bursts.

  Further, in the present embodiment, as shown in the image shown in FIG. 10, when a crack Y1 occurs in the sidewall portion 12S of the tire 12, the brightness of the part where the crack K1 occurs is compared with the brightness of the normal part. Go down. For this reason, the occurrence of cracks in the sidewall portion 12S can also be detected from the change in luminance.

[Other Embodiments]
Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art. For example, the present invention can also be applied to failure detection of parts other than the bead part 12 </ b> A on the side surface of the tire 12.

DESCRIPTION OF SYMBOLS 10 Tire side wall part failure detection apparatus 11 Drive apparatus 12 Tire 12A Tire bead part 12S Tire side wall part (side surface of tire)
16 lamp (light source)
18 Optical fiber (light guide means)
20 Video camera (photographing device)
24 PC (image processing means)
26 Camera cable 28 Camera adapter 30 Cable

Claims (10)

  The side of the tire is photographed, and the reference high-intensity part where the brightness due to regular reflection at the reference position without inclination along the circumferential direction of the side of the tire by the light projected from the light source is higher than a predetermined value, and corresponds to the reference position When checking whether there is another high-intensity part having a brightness higher than the predetermined value at a radial position other than the reference position, and confirming that there is the other high-intensity part, A tire side surface failure detection method for detecting a failure of the side surface from a distance in the tire circumferential direction between the reference high brightness portion and the other high brightness portion in the captured image and the brightness of the other high brightness portion.   2. The photographing interval is set to nT ± (T / N) when the entire circumference of the side surface of the tire is photographed by dividing it into N times, and the tire rotation period is T and n is a positive integer. The tire side surface failure detection method described in 1.   The tire side surface failure detection method according to claim 2, wherein the light source is turned on in synchronization with the photographing interval.   The tire side surface failure detection method according to any one of claims 1 to 3, wherein projection light from the light source is guided to the vicinity of the side surface of the tire.   The tire side surface failure detection method according to claim 1, wherein the tire is stopped when the side surface failure is detected. A driving device for rolling the tire;
At least one photographing device for photographing a side surface of the tire;
A light source that projects projection light onto a side surface of the tire;
Corresponding to a reference high-intensity part where the luminance by regular reflection at a reference position without inclination along the circumferential direction of the side surface of the tire is higher than a predetermined value from the image data of the side surface photographed by the photographing device, and the reference position When checking whether there is another high-intensity part having a brightness higher than the predetermined value at a radial position other than the reference position, and confirming that there is the other high-intensity part, Image processing means for detecting a failure of the side surface from the distance in the tire circumferential direction between the reference high-intensity part and the other high-intensity part in the captured image and the luminance of the other high-intensity part;
A tire side failure detection device.   The photographing device shoots by dividing the entire circumference of the side surface of the tire into N times, and when the rotation period of the tire is T and n is a positive integer, the photographing interval is nT ± (T / N) The tire side surface failure detection device according to claim 6.   The tire side failure detection device according to claim 7, wherein the light source is turned on in synchronization with the photographing interval.   The tire side surface failure detection device according to any one of claims 6 to 8, further comprising light guide means for guiding the projection light of the light source to the vicinity of the tire.   The tire side surface failure detection device according to any one of claims 6 to 9, wherein the driving device stops when the image processing means detects the side surface failure.

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