JP2000283893A - Tire inspection device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To establish an automated inspection method by a physical method instead of a sensory analysis. SOLUTION: The tire inspection device consists of a scanning mechanism for appropriately positioning a temperature-measuring device for a tire 7 to be inspected, a temperature change imparting device 2 for generating a temperature change in the tire 7 to be inspected, and an optical device for optical detecting a heat ray being emitted from the surface of the tire 7 to be inspected. The temperature change does not strictly report the absolute value of physical properties but is a physical phenomenon for fully reflecting the difference in physical properties. The defect in layer structure as in the tire faithfully appears as the relative change in a surface temperature. The presence or absence of an internal defect can be verified clearly according to the surface temperature distribution by the temperature change in the surface. The presence or absence, location, and spread may be determined as a relative difference, and no strict measurement of temperature is required.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tire inspection apparatus and a tire inspection method, and more particularly to a tire inspection apparatus and a tire inspection method for detecting internal defects and defects.

[0002]

2. Description of the Related Art A tire has a shape surrounded by a partial torus surface and has a complicated structure in which a rubber soft layer and a metal rigid layer are multilayered. Such a multilayer structure is different between the ground plane side part and the side part, and is more complicated. Such tires need to be subjected to highly reliable inspections. Inspection of the intima, which is important for ensuring airtightness, is particularly important for both the ground contact surface side portion and the side surface side portion. The inner film is required to have uniformity in thickness and good adhesion to the inner layer. When the adhesion between the intermediate layer and the inner layer is insufficient, voids are generated in the film, or the film thickness is not uniform,
A phenomenon occurs in which swelling occurs on the inner surface of the tire and cords are observed from the inner surface. Careful inspection has been performed for uniformity and goodness.

A conventional inspection method is based on a sensory inspection by a skilled inspector. Inspectors touch the inner surface with their fingertips while rotating the tires to perform a tactile inspection to check for local bulges, a visual inspection to visually check for unevenness on the inner surface, local changes in patterns, and the presence or absence of different patterns with the naked eye. Inspection of defects appearing on the inner surface is performed.

[0004] The continuous time during which a skilled inspector can fully demonstrate his / her ability is limited, and the duration during which the best inspecting ability can be exercised is short. Many inspectors are required to keep the inspection accuracy constant.

Conventional methods for detecting physical properties, such as ultrasonic diagnosis and electrical conductivity diagnosis, and image recognition methods for detecting shapes, are capable of reliably detecting defective portions that appear in a complicated structure globally and locally. Difficult to detect.

It is desired to establish an automated inspection method instead of a sensory test. It is desirable to establish a physical inspection method that is comparable to the highest inspection ability by inspectors. Further, it is desired to establish an inspection method suitable for a complicated structure of a tire, and it is possible to detect a defect regardless of the type, and to further determine the type of the defect. Higher speed is desired.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automated tire inspection apparatus and method which can replace sensory tests. Another object of the present invention is to provide an automated tire inspection apparatus and tire inspection method using a physical method instead of a sensory test. Still another object of the present invention is to provide a tire inspection device and a tire inspection method capable of classifying a type of a defect and detecting its existence. Still another object of the present invention is to provide
An object of the present invention is to provide a tire inspection apparatus and a tire inspection method that are automated and accelerated by a physical method instead of a sensory test.

[0008]

SUMMARY OF THE INVENTION A tire inspection apparatus according to the present invention comprises a scanning mechanism for appropriately positioning a temperature change detection device with respect to a tire to be inspected, and a temperature mechanism for generating a temperature change in the tire to be inspected. It comprises a change giving device and an optical device for optically detecting a heat ray radiated from the surface of the tire to be inspected. The temperature change is a physical phenomenon that does not strictly notify the absolute value of the physical property, but reflects the difference in the physical property well. Defects in the layer structure, such as tires, manifest themselves as relative changes in surface temperature. The presence or absence of internal defects can be clearly confirmed from the surface temperature distribution due to the temperature change of the surface. Its presence, location, and extent may be known as relative differences, and absolute measurement of temperature is not required.

The surface of the tire to be measured is preferably an inner surface. In this case, the temperature change applying device is arranged on the side of the inner surface of the tire to be inspected. The temperature change applying device is a heating device or a cooling device. When the heating position changes while the temperature change providing device partially heats the tire to be inspected, it is desirable to detect a temperature distribution in a time zone in which the temperature changes sharply.

The optical device partially detects the heat radiated from the surface of the tire to be inspected. In this case, it is effective to scan the detection position to make the temperature change remarkable. The change in the detection position is preferably continuous. For scanning the detection position, it is more advantageous to rotate a light optical mirror without rotating the tire. By using a mirror with a flat reflecting surface and a cylindrical lens, the linear area can be measured simultaneously.By using a mirror with a conical reflecting surface and a cylindrical lens together,
Arc-shaped regions can be measured simultaneously. The circular area can be measured simultaneously by changing the focal position of the lens. Simultaneous measurement means non-scan measurement.

As a heating method, overall (global) heating is effective. The surface temperature distribution caused by the temperature change due to the natural cooling of the tire having the uniform temperature distribution well reflects the internal structure of the tire. Forced cooling, which temporally accelerates the occurrence of temperature changes, facilitates high-speed inspection. Active heating is not necessary. Tires that are at the natural temperature of the test room prior to measurement can be considered to be naturally heated. In this case, active heating or active cooling can be regarded as applying a temperature change.

Heating or cooling is a positive temperature change. That is, a combination of natural heating and active cooling, a combination of natural cooling and active heating, and a combination of active heating and active cooling are positive temperature change applications. The positive temperature change application is performed globally or locally. Combination of global heating / cooling and local heating / cooling can be freely performed. Within such a combination, a further difference in heating and cooling can be provided.

The optical device is positioned on the side of the inner surface of the tire to be inspected by the three-dimensional scanning mechanism. The relative positional relationship between the optical detection system and the inner surface of the tire is important in terms of temperature change detection accuracy and temperature change speed. If the type of the tire changes, the scanning mechanism changes the coordinate position of the temperature change providing system and the temperature measuring system (optical system) to the optimum position corresponding to the type.

When the optical device is disposed at a position deviated from the center position of the tire to be inspected, the optical device changes the detection position while partially detecting the heat radiated from the surface of the tire to be inspected. The selection of the point-like area, the linear area, the planar area, and the entire area can be made by changing the setting of the optical system. The optical device is configured by a combination of a lens selected from a spherical lens, a linear cylindrical lens, a circular cylindrical lens, and a mirror selected from a planar reflecting mirror and a conical reflecting mirror, and adjusting a focal position. Thus, selection of a point-like area, a linear area, and a planar area is further possible.

When the optical device is arranged at the center position of the tire to be inspected, the heat radiated from the surface of the tire to be inspected is entirely detected, and the detected position is not changed. The optical device includes a light receiving device, and a mirror device interposed between the heat radiation region on the inner surface of the tire to be inspected and the light receiving device, and the mirror device includes a rotating device for rotating the reflection surface thereof. become.

The tire inspection method according to the present invention is a method for inspecting a tire formed from an inner layer and an outer layer having a higher thermal conductivity than the inner layer, wherein a step of causing a temperature change in the inner layer; Detecting the heat dose of the heat rays radiating from the inner surface of the changing inner layer. The heat dose distribution corresponds to the temperature distribution with a good approximation. No rigorous measurement of temperature is required. Although the absolute value of the temperature distribution in which the temperature difference appears is ambiguous, the temperature distribution clearly indicates the existence of the inconvenient part and the area where the disadvantage exists.

When the heating position changes while the temperature change applying device partially heats the tire to be inspected,
It is desirable to detect a temperature distribution in a time zone in which the temperature changes rapidly, and the tire inspection method according to the present invention includes a step of heating a first local area of the surface of the tire, and a step of heating the tire away from the first local area. Measuring the radiation emitted from the second local area of the surface; and performing a first scan of heating the first local area and a second scan of measuring the second local area to reduce tire failure. And a step for determining. By properly setting the distance between the first local region and the second local region, the measurement of the temperature in a time zone in which the change is severe is strict. Such a distance, which is a spatial distance, is a function of the scanning speed.

The scan is continuous. The sequence includes digitized movement. Both scans are performed at a synchronized scan speed. A preferred means for local heating is a laser. By configuring the optical system so that the laser and the emitted light pass optically on the same optical axis, the optical system can be simplified. The optical system is formed by a lens, a prism, a reflecting mirror, an optical fiber, and a filter.

It is desirable that both scans be performed two-dimensionally. The one-dimensional part of the two-dimensional scanning is performed by the rotation of the optical axis of the laser, and the other one-dimensional part of the two-dimensional scanning is performed by the rotation of the tire. Preferably, the separation distance between the first local area and the second local area is variable. The difference between the measurement values at two different positions by the measurement of the second local region is obtained. The difference can reduce the influence of the tire-specific temperature distribution.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with the drawings, a tire inspection device according to an embodiment of the present invention is provided with a control device. As shown in FIG. 1, the control device 6 is provided together with the tire installation table 1, the temperature change applying device 2, the temperature change detection device 3, the scanning mechanism 4, and the signal processing device 5.

The control device 6 is electrically and mechanically provided for the tire installation table 1, electrically provided for the temperature change providing device 2, and provided electrically or mechanically for the temperature change detecting device 3. In addition, they are electrically and mechanically connected to the scanning mechanism 4 and electrically connected to the signal processing device 5, respectively. One tire 7 to be inspected to be inspected is placed on the tire installation table 1.

FIG. 2 shows an embodiment of the tire inspection apparatus according to the present invention. The rotation shaft 8 is rotatably supported by the tire installation table 1. The rotation shaft 8 is controlled by the control device 6 to rotate at an arbitrary rotation speed, stop at an arbitrary rotation position, and can be fixed at the stop position. The rotation shaft 8 can be further raised and lowered with respect to the tire installation table 1. A tire mounting base 9 is connected to the rotating shaft 8.

A moving table 11 is mounted on the upper surface of the mounting table 9. The moving table 11 is movable in one axis direction. The moving position of the moving table 11 can be adjusted by a bolt 12 supported by the mounting table 9. Tire 7 is mobile 1
The position is fixed on the movable table 11 by four rotatable rollers 13 fixed to 1. Roller 13
Are rotatable on the movable base 11 respectively.

The tire 7 is rotatable with respect to the moving table 11. The rotational position of the tire 7 with respect to the moving table 11 can be freely set. A plurality of columns 14 stand on the tire installation table 1. An X-axis / Y-axis scanning rail 15 is suspended between the plurality of columns 14 in the horizontal direction.
The X-axis / Y-axis scanning rail 15 has a plurality of X-axis portions.
It is suspended horizontally between the columns 14.

The scanning mechanism 4 moves on an X-axis direction rail extending in the X-axis direction, and moves on a Y-axis direction rail fixed to the X-axis direction moving body and extending in the Y-axis direction. The Y-axis direction moving body is a conventional means that can move to an arbitrary position on the XY plane and be fixed at the moving position. Such a scanning mechanism is controlled by the control device 6.

A support arm 16 (a Z-axis scanning rail, which will be described later) extending in the vertical direction is fixed to the scanning mechanism 4.
The support arm 16 is supported by the above-described Y-axis direction moving body of the scanning mechanism 4, and moves up and down in the Z-axis direction (vertical direction) perpendicular to the XY plane with respect to the Y-axis direction moving body. And can be fixed to the Y-axis direction movable body at any of the vertical positions.

At the lower end of the support arm 16, a temperature change applying device 2
And the temperature change detection device 3 are fixedly provided.
By the three-dimensional position control of the support arm 16 whose position is controlled by the scanning mechanism 4, the temperature change applying device 2 and the temperature change detecting device 3 can adjustably maintain a preferable positional relationship with respect to the tire 7 to be inspected.

The moving table 1 supported on the rotating shaft 8 at the lowered position
1, the tire 7 to be inspected is fixed to the upper surface of the
The rotating shaft 8 is raised, and the scanning mechanism 4 further moves the support arm 1.
6 is scanned two-dimensionally to position the temperature change applying device 2 and the temperature change detecting device 3 in the central region of the tire 7 to be inspected. The scanning mechanism 4 can adjust the distance of the temperature change detection device 3 to the inner surface of the tire 7 to be inspected and the direction toward it.

The tire 7 to be inspected by the temperature change applying device 2
Is locally heated to change the temperature of the inner surface portion. The temperature change detecting device 3 adjacent to the temperature change applying device 2 detects the temperature of the inner surface portion that rotates while locally changing the temperature and the temperature change.

The temperature of the inner surface portion detected in this way is converted into an electric signal by a signal converter belonging to the temperature change detecting device 3 and transmitted to the signal processing device 5. The signal processing device 5 converts the received change in the electric signal into temperature distribution data which is temperature change data corresponding to the temperature change. The signal processing device 5 has a function of processing the received signal. The processing device for that purpose is a conventional signal processing device including a filter, an amplifying device, and the like for reducing unnecessary signals and enhancing necessary signals.

Based on the signals processed in this way, the signal processing device 5 evaluates and determines a defect of the tire 7 to be inspected. The method of evaluation / judgment will be described later. Inspection tire 7 for temperature change application device 2 and temperature change detection device 3
May be relative to each other, and a rotary scanning mechanism may be added to the scanning mechanism 4 to make the support arm 16 a rotation axis.

FIG. 3 shows another embodiment of the tire inspection apparatus according to the present invention. This embodiment is different from the embodiment of FIG. 2 in that the temperature change providing device 2 is omitted and a uniform temperature change providing device 2 ′ is provided instead of the temperature change providing device 2. . A second scanning mechanism 4 ′ (hereinafter, the above-described scanning mechanism 4 is referred to as a first scanning mechanism) is further provided on a portion of the X-axis / Y-axis scanning rail 15 in the X-axis direction.
Is provided.

The second scanning mechanism 4 'is suspended on an X-axis / Y-axis scanning rail 15. The second scanning mechanism 4 ′ is controlled in position on the X-axis direction portion of the X-axis / Y-axis scanning rail 15 and moves in the horizontal direction, and is fixed to the X-axis direction moving body. And a Y-axis direction moving body guided and moved by the Y-axis direction rail. The second scanning mechanism 4 ′ moves while being electrically controlled by the control device 6.

The moving body of the second scanning mechanism 4 'in the Y-axis direction includes:
A second support arm 16 'extending in the vertical direction is supported so as to be able to move up and down. A second temperature change applying device 2 'is fixedly provided at the lower end of the second support arm 16'. The second temperature change applying device 2 ′ can adjustably maintain a preferable directional relationship and a positional relationship with respect to the tire 7 to be inspected.

The second temperature change applying device 2 'is provided as a uniform heating device over the entire area. By operating the first scanning mechanism 4 to move the first support arm 16 up and down, the temperature change detecting device 3
From the tire 7 to be inspected, and instead, the second scanning mechanism 4 ′ is operated to move the second support arm 16 ′,
The second temperature change applying device 2 ′ is positioned in the central region of the tire 7 to be inspected, and controlled by the control device 6, and is controlled by the second temperature change applying device 2 ′ to be the entire inner peripheral area which is the inner surface portion of the tire 7 to be inspected. Heat the surface approximately evenly.

In the reverse order, the positions of the second temperature change applying device 2 'and the temperature change detecting device 3 are exchanged, and the evaluation and judgment as described above are performed. In the previous step, a large number of tires to be inspected may be simultaneously heated in the heating chamber, and one of the tires may be sequentially taken out of the heating chamber and placed on the movable base 11.

FIG. 4 shows still another embodiment of the tire inspection apparatus according to the present invention. This embodiment is different from the embodiment of FIG. 2 in that the temperature change providing device 2 is omitted and the local cooling device 2 is used instead of the temperature change providing device 2.
1, and the second scanning mechanism 4 'and the temperature change applying device 2' are exactly the same as those in the embodiment of FIG.

Since the evaluation and judgment of the tire 7 to be inspected are performed based on the temperature change, whether the temperature is positive or negative with respect to the object is substantially equal or equivalent. is there. In this embodiment, it is preferable that the tire 7 to be inspected heated in the previous step is locally or entirely cooled. The evaluation / judgment method is as described above. The point of relative rotation is also as described above.

FIG. 5 shows an embodiment relating to the rotation of the tire mounting table 9. A drive motor 22 is provided on the rotating shaft 8.
Is provided. It is desirable that the drive motor 22 fixed and supported by the tire installation table 1 has a variable speed function. The above-described movable table 11 slidably mounted on the upper surface of the tire installation table 9 is formed of two symmetric movable tables 11A and 11B.

The bolt 12 is formed as a centering screw shaft 12. The alignment screw shaft 12 has a screw portion. The threaded portion is formed as a reverse thread on one side and the other side. Alignment screw shaft 12
A, 11B coaxially penetrates, one side of the threaded portion is screwed into and penetrated by the one side symmetrical movable base 11A, and the other side threaded portion is screwed by the other side symmetrical movable stage 11B. Penetrates.

When the centering screw shaft 12 rotates, the two-sided symmetric movable stages 11A and 11B move in opposite directions. In this way, the two-sided symmetrical moving tables 11A, 11 which move in the opposite direction are provided.
The center line of B is immobile. After the position of the tire mounting table 9 is once adjusted with respect to the rotating shaft 8, when the centering screw shaft 12 is driven to hold a tire having an arbitrary diameter with the roller 13, the center point of the tire always rotates. It is on the axis of rotation of the shaft 8. Such a centering mechanism that does not change the center position of the tire can shorten the inspection time of a tire having an arbitrary diameter.

FIGS. 6A and 6B show an embodiment of the temperature change applying device 2 shown in FIG. The temperature change applying device 2 is provided with a cylindrical casing 31. The casing 31 is formed of a heat insulating material.
The casing 31 is covered with a cover 32.

In the casing 31, a disc-shaped air space 33 is provided.
Are formed. The disc-shaped airspace 33 includes the casing 31.
Are separated by a dividing plane 35 of the lunar portion 34 of the first embodiment. The dividing plane 35 is formed as a set of lines substantially parallel to the axis of the tire 7 to be inspected, and is positioned near the inner peripheral surface of the tire 7 to be inspected in that state.

The disk-shaped space 33 is also divided by two planes which are perpendicular to the division plane 35 and are parallel to each other. Part 2
Reflector or reflector 3 that reflects light or heat rays 37 to a plane
6A and B are joined. The reflectors 36A and 36B face each other and can repeatedly reflect the heat ray 37 therebetween. In the casing 31, a columnar space 38 that is continuous with the disk-shaped space 33 is formed. Also on the dividing plane 35,
Another reflecting mirror 40 is joined.

A power supply unit 39 is inserted into the cylindrical airspace 38. A hole is formed in the central region of the reflectors 36A and 36B, and an axially symmetric heat ray radiator 41 penetrates the hole. A heating element 42 is mounted in the central area of the heat ray radiating element 41. The heating element 42 is connected to the power supply unit 39 and is thereby heated. The power supply unit 39 receives power supply from the external control device 6 via the electric wire 43.

The heat ray radiator 41 is provided around the disc-shaped space 33.
Concentrically with the cylindrical circular lens 44
Are fixed to the casing 31 by set screws 45. Cylindrical circular lens 4
Reference numeral 4 denotes a heat-resistant optical component formed by bending a cylindrical lens (linear) into a circular or ring shape.

The outer peripheral area of the casing 31 is positioned near the inner surface of the tire 7 to be inspected by the scanning mechanism 4. Electricity is supplied to the power supply unit 39, and the heating element 42 (for example, a ceramic heater, a halogen lamp, a xenon lamp,
When the heat ray radiator 41 is heated by generating heat from a tungsten light emitter, a laser, or a microwave, a heat ray is emitted from the peripheral surface of the heat ray radiator 41.

The heat ray 37 repeats the reflection within a plurality of times on the opposing surfaces of the reflectors 36A and 36B, and is in a radial direction with respect to the central axis of the heat ray radiator 41 when passing through the cylindrical circular lens 44. The inner surface of the tire 7 to be inspected can be locally heated within a certain rotation angle range while being radiated from the cylindrical circular lens 44 while having a divergence angle and being focused. The inner surface of the rotating inspected tire 7 is heated over the entire circumference.

FIG. 7 shows a modification of the temperature change applying device 2 'shown in FIG. The temperature change applying device 2 '
Is exactly the same as the temperature change applying device 2 shown in FIG. 6 except for the size. The temperature change providing device 2 ′ is a similar configuration of the temperature change providing device 2 that is enlarged. The diameter of the outer shape of the temperature change applying device 2 ′ is slightly smaller than the diameter D of the center hole of the tire 7 to be inspected.

The temperature change applying device 2 ′ is generally located in the central region of the tire 7 to be inspected. The inner surface of the inspected tire 7 is simultaneously heated by the hot wire 37 radiated from the cylindrical circular lens 44 of the temperature change applying device 2 ′, and the second surface is heated for global heating.
No rotation of the support arm 16 'is required. The inspection method of the tire 7 to be inspected is exactly the same as that of the embodiment shown in FIG.

FIGS. 8A and 8B show an embodiment of the temperature change applying device 21 shown in FIG. The temperature change applying device 21 is provided with a cylindrical casing 31 ′. The casing 31 'is formed of a heat insulating material. The casing 31 'is covered with a cover 32'. In the casing 31 ', a disc-shaped space 33' is formed.

The disk-shaped space 33 'is delimited by a delimiting plane 35' of the lunar portion 34 'of the casing 31'.
The dividing plane 35 'is formed as a set of lines substantially parallel to the axis of the tire 7 to be inspected, and is positioned near the inner peripheral surface of the tire 7 to be inspected in that state.

The disk-shaped space 33 'is also divided by two planes which are orthogonal to the division plane 35' and are parallel to each other. A guide plate 52 that reflects the cold air 51 is joined to the two planes. The guide plates 52 oppose each other and guide the cool air 51 therebetween in the radial direction. The casing 31 'has a columnar space 38' continuous with the disk-shaped space 33 '. Another guide plate 53 is also joined to the dividing plane 35 '.

The air introduction pipe 54 communicating with the cylindrical space 38 '
Extends through the casing 31 '. A hole 55 is formed in one central area of the guide plate 52. In the other central area of the guide plate 52, a cone-shaped projection surface 56 is provided. The cool air whose temperature is controlled by the control device 6 is introduced into the disk-shaped air space 33 'through the air introduction pipe 54, the cylindrical air space 38', and the hole 55.

The cool air thus introduced is applied to the projection surface 56.
The flow is rectified so as to be directed in the radial direction, and a flow is formed in the radial direction between the two guide plates 52 to form a flow 57 which is ejected in a substantially radial direction from the outer edge of the disk-shaped space 33 ′. 7 is locally cooled.

The temperature change applying device 21 itself can be a heating device. By sending hot air instead of cold air 51, the tire 7 to be inspected can be heated. If cool air is sent after the heating, it is not necessary to transfer the device and the tire between the heating step and the cooling step. The temperature change applying device 21 can be used as a global heating device if its size is enlarged.

FIG. 9 shows an embodiment of the temperature change detecting device 3. The temperature change detecting device 3 includes a tire 7 to be inspected.
Is provided as an optical detection system having an optical axis L parallel to a line orthogonal to the axis of the optical axis. The optical detection system includes an integral sensor holder 61. A rotation shaft 62 having a rotation axis corresponding to the optical axis L is driven to rotate by a mirror rotation motor 63.

The mirror rotation motor 63 is fitted and fixed in the sensor holder 61. A scanning type detection mirror 64 is fixed and attached to the rotating shaft 6. The reflecting surface, which is the plane of the scanning detection mirror 64, has its radiation direction crossing the optical axis L, which is the rotation axis of the rotation shaft 62, at an appropriate angle (approximately 45 degrees).

An optical detector 65 is fitted and attached to the sensor holder 61. Optical detector 65
Are formed from a spot-type infrared sensor 66 and an amplifier such as a photomultiplier tube (not shown). The spot-type infrared sensor 66 includes an optoelectronic element that detects infrared rays, far infrared rays, and microwaves. A condensing lens (not shown) may be positioned on the front surface of the spot-type infrared sensor 66.

The reflection surface of the scanning type detection mirror 64 optically faces the spot type infrared sensor 66. A condenser lens 67 is interposed between the spot-type infrared sensor 66 and the scanning detection mirror 64 and fixed to the sensor holder 61. The sensor holder 61 is connected to the support arm 16 or the temperature change applying device 2 shown in FIG. The sensor holder 61 can approach the inner surface portion of the tire 7 to be inspected by a distance corresponding to the extension of the connecting tool 68, that is, a distance that does not hinder the rotation of the tire 7 to be inspected.

The optical axis L 'of the conical light beam reflected from one point P on the inner peripheral surface of the tire 7 to be inspected is substantially at the center point of the mirror 64 for scanning detection (the reflecting surface of the mirror 64 for scanning detection). And the optical axis L). Thus, the position of the sensor holder 61 is adjusted by the scanning mechanism 4 or the like. The light energy cone radiated from the point P is reflected by the scanning detection mirror 64 and collected by the condenser lens 67. The light receiving surface of the spot-type infrared sensor 66 is located at the focal position with respect to the point P.

The light energy collected by the spot-type infrared sensor 66 is photoelectrically converted, and the photoelectrically converted signal is transmitted to the signal processing device 5 after being amplified in terms of voltage. Since the magnitude of the light energy is a function of the temperature at the point P, the photoelectric conversion signal contains data corresponding to the temperature change.

By rotating the scanning detection mirror 64, a minute line region having a direction A orthogonal to the circumferential direction of the tire 7 to be inspected is scanned, and the temperature change of the minute region is continuously detected. Can be. Further, by rotating the tire 7 to be inspected, it is possible to scan in the circumferential direction and detect a temperature change over the entire inner surface.

FIG. 10 shows another embodiment of the temperature change detecting device 3. The temperature change detection device 3 is provided as an optical detection system having an optical axis L ′ parallel to the tire axis. The optical detection system has an integral sensor holder 61 '. A swing shaft 62 'having a rotation axis perpendicular to the optical axis L' is rotationally driven to rotate by a mirror swing motor 63 '.

The mirror swing motor 63 'is fixed to the sensor holder 61'. Scanning detection mirror 64 '
Are fixedly attached to the swing shaft 62 '. The reflecting surface, which is the plane of the scanning type detection mirror 64 ', has its radiation direction orthogonal to the rotation axis of the swing shaft 62'. The pivot axis of the pivot shaft 62 ′ is substantially parallel to the axis of the tire 7 to be inspected.

The spherical lens 71 is attached to the sensor holder 61 '.
It is stuck to. The optical axis L ′ of the spherical lens 71 is orthogonal to the pivot axis of the pivot shaft 62 ′. An optical detector is fitted and attached to the sensor holder 61 '. The optical detector is a linear array type infrared sensor 7
2 and an amplifier such as a photomultiplier tube (not shown).

The linear array type infrared sensor 72 is a photodetector in which photodetectors (photoelectric conversion elements) are arranged in a direction parallel to the reflection surface of the scanning type detection mirror 64 'and orthogonal to the optical axis L'. The linear array type infrared sensor 72 includes an optoelectronic element for detecting infrared rays, far infrared rays, and microwaves. A spherical lens 71 is interposed between the scanning type detection mirror 64 ′ and the linear array type infrared sensor 72. The function of the connector 68 is as described above.

In this embodiment, scanning can be performed in units of lines, instead of scanning point by point. The line area P 'on the inner surface of the tire 7 to be inspected is a mirror 64' for scanning detection.
And a tire 7 to be inspected, an image is mapped as a real image on the photoelectric conversion element surface of the linear array type infrared sensor 72.

Such a temperature change detection scanning system can continuously detect the temperature change of the inner surface portion of the tire 7 to be inspected line by line in the direction orthogonal to the circumferential direction of the tire 7 to be inspected. Further, by rotating the tire 7 to be inspected, it is possible to scan in the circumferential direction and detect a temperature change over the entire inner surface.

FIG. 11 shows still another embodiment of the temperature change detecting device 3. The temperature change detection device 3 is provided as an optical detection system having an optical axis L ″ orthogonal to the axis. The optical detection system is an integral sensor holder 6.
1 ". An optical detector 65" is fitted and attached to the sensor holder 61 ".

The optical detector 65 ″ is formed by a two-dimensional infrared sensor 82 and an amplifier such as a photomultiplier tube (not shown). The optical axis L ″ is the outer peripheral portion of the tire 7 to be inspected. Are substantially perpendicular to the inner peripheral surface 81 of the first member. Spherical lens 83
Is provided between the inner peripheral surface 81 of the outer peripheral portion of the tire 7 to be inspected and the two-dimensional infrared sensor 82.

Such an optical system corresponds to a normal camera. In this embodiment, the average temperature of a certain rotation angle range of the inner surface portion of the tire 7 to be inspected is detected, and the detected local range is two-dimensionally compared with that of the above-described embodiment. It is suitable for mainly inspecting the bottom of the tire.

FIG. 12 shows still another embodiment of the temperature change detecting device 3. The structure of the temperature change detecting device 3 is exactly the same as that shown in FIG. 11, and the arrangement relation to the tire 7 to be inspected is also exactly the same as that shown in FIG. Further, between the spherical lens 83 and the inner peripheral surface 81 of the outer peripheral portion of the tire 7 to be inspected, a set of transmissive reflecting mirrors 91 is provided.

The transmission type reflection mirror 91 has reflection surfaces 91A and 91B orthogonal to each other, and the reflection surface 91A is formed on the inner peripheral surface 8A.
1, and the reflecting surface 91B faces the other half of the inner peripheral surface 81. The inner peripheral surface 92A on one side of the side peripheral portion of the inspected tire 7 is inclined at an inclination angle of approximately 45 degrees with respect to the reflective surface 91A, and the other inner peripheral surface 92B on the other side peripheral portion of the inspected tire 7 is It is inclined at an inclination angle of approximately 45 degrees with respect to the reflection surface 91B.

The heat rays 93 radiated from the inner peripheral surface 92A are reflected by the reflection surface 91A of the transmission type reflection mirror 91 and imaged by the two-dimensional infrared sensor 82, and the heat rays 94 radiated from the inner peripheral surface 92B are transmitted type. The heat rays 95 reflected from the reflection surface 91B of the reflection mirror 91 and imaged by the two-dimensional infrared sensor 82 are radiated from the inner peripheral surface 81 to the reflection surface 9 of the transmission type reflection mirror 91.
1A, two-dimensional infrared sensor 82 transmitted through reflective surface 91B
Image. In this embodiment, it is possible to detect a temperature change in a wider local area that covers three areas of the inner inner surface of the inspected tire 7 at one time.

FIG. 13 shows still another embodiment of the temperature change detecting device 3. The temperature change detection device 3 is shown in FIG.
Instead of the two transmission-type reflection mirrors 91, a total reflection mirror 111 having a cone-shaped reflection surface is used. 13 is exactly the same as FIG. 12 except for the optical axis direction of the temperature change detection device 3 with respect to the tire 7 to be inspected. The optical axis direction M is orthogonal to the center axis of the tire 7 to be inspected.

The axis of central symmetry of the conical surface 112 which is the reflecting surface of the total reflection mirror 111 substantially coincides with the optical axis M. Heat rays 113 radiated from an arbitrary point P ″ in the approximate circular arc region N on the torus cross section of the inner inner surface portion of the tire 7 to be inspected
Collects light on the two-dimensional infrared sensor 82.

The temperature change of the inner surface of the tire 7 to be inspected can be continuously detected line by line in the direction perpendicular to the circumferential direction of the tire 7 to be inspected. Further, by rotating the tire 7 to be inspected, it is possible to scan in the circumferential direction and detect a temperature change over the entire inner surface.

FIG. 14 shows still another embodiment of the temperature change detecting device 3. The temperature change detection device 3 is shown in FIG.
The point that the total reflection mirror 111 of No. 3 is used is common to the embodiment of FIG. The optical axis K of the integral sensor holder 113 substantially coincides with the center line of the tire 7 to be inspected.

The total reflection mirror 112 is provided on the cone-shaped reflection surface 1.
15. The central axis of symmetry of the cone-shaped reflection surface 115 substantially coincides with the optical axis K. Inspection tire 7
Heat ray 116 radiated from any point on the entire inner peripheral surface of
Are focused (converged) via the lens 83 on the photoelectric conversion surface of the two-dimensional infrared sensor 82, which is a very small area.

According to this embodiment, it is possible to simultaneously detect a temperature change in the whole area at the bottom of the tire 7 without rotating the tire 7 to be inspected. The image can be formed in a ring shape, and the temperature change of each point in the whole area can be detected simultaneously by the address of the CCD.

FIG. 15 shows the details of the scanning mechanism 4. The scanning mechanism 4 includes an X-axis / Y-axis scanning rail 15 and a support arm 16. X-axis / Y-axis scanning rail 15 and support arm 1
6 is an X-axis scanning rail 121 and a Y-axis scanning rail 12
2, corresponding to the Z-axis scanning rail 123, respectively. The X-axis direction moving body 124 is an X-axis scanning rail 121.
The X-axis scanning rail 121 includes a movement position control mechanism so as to be fixed at an arbitrary X coordinate position. As such a movement position control mechanism,
Conventional techniques such as a gear meshing structure, a screw screwing mechanism, and a magnetic non-contact positioning mechanism can be applied.

The Y-axis scanning rail 122 has a coordinate index orthogonal to the X-axis scanning rail 121, and extends in the direction orthogonal to the X-axis scanning rail 121 to move in the X-axis direction moving body 124.
It is fixed to. The Y-axis direction moving body 125 moves while being guided by the Y-axis scanning rail 122, and includes another moving position control mechanism therein so as to be fixed at an arbitrary Y coordinate position of the Y-axis scanning rail 122. I have.

The Z-axis direction moving body 126 is oriented perpendicularly to the Y-axis scanning rail 122 in the vertical direction, relatively guided and moved by the Y-axis direction moving body 125, and moves at its own arbitrary Z coordinate position. Another moving position control mechanism is further included inside so as to be fixed relative to the Y-axis direction moving body 125. The Z-axis direction moving body 126 includes a Z-axis scanning rail 123.
Is the same as

The lower end of the Z-axis direction moving body 126 is provided with the temperature change applying device 2 (see FIGS. 2 and 3), the temperature change detection device 3 (see FIGS. 2 and 3), and the local cooling device 21 (see FIG. 4). reference)
Is formed as a mounting seat 127 to which the.
The temperature change application device 2 and the temperature change detection device 3 are moved to an arbitrary position in the three-dimensional coordinate system by such a scanning mechanism 4 and are fixed at that position. 6.

FIG. 16 shows the signal processing device 5 shown in FIG.
Is shown. The signal processing device 5 includes a signal processing unit 131. The signal processing unit 131 has an external I
Via the I / O device 137 and the memory device 129, the rotation angle position signal 133 of the tire installation table 1, the temperature energy signal 134 output by the temperature change applying device 2, the temperature signal detected by the temperature change detection device 3 (or the temperature change) Signal) 1
35, the mounting seat 127 output by the three-dimensional scanning mechanism 4 or the three-dimensional coordinate position signal 136 of the temperature change providing device 2 and the temperature change detecting device 3 which are positioned relatively to the mounting seat 127 are input to the respective seats. You.

The signals are processed by the signal processing unit 131, and the signals processed by the signal processing unit 131 are output to the output device 138. The physical quantity detection system 139 forms a loop with the control device 6 and the signal processing device 5. I / O
The device 137 includes an A / D converter and a D / A converter, and converts the temperature signal 135 forming a pair with the position signal into a digital signal or vice versa.

The signal processing section 131 determines a temperature change position where the temperature signal 135 changes suddenly from the three-dimensional coordinate position signal 136 and the rotation angle position signal. The signal processing unit 131 determines whether or not there is a sudden change in the temperature of the inspected tire 7, the position of the sudden change in the temperature,
A calculation unit (not shown) for detecting the size of the sudden temperature change part and calculating the position and size of the part is provided.

The control device 6 controls each operation of the tire installation table 1, the temperature change applying device 2, the temperature change detection device 3, and the scanning mechanism 4. The control device 6 performs first position control for matching the center position of the tire 7 to be installed on the tire installation table 1 with the rotation center position of the tire installation table 1, and the inner surface of the tire 7 to be heated. Second position control for positioning the temperature change detection device 3 at an appropriate position with respect to the temperature change application device 2 for detecting the temperature after the temperature of the inner surface portion of the temperature change detection device 3 becomes an appropriate value.
Position control for controlling an appropriate position of the sensor, heat supply control for appropriately controlling a heating amount emitted by the temperature change detecting device 3, an origin for returning the motion system and the heating system to the origin after the completion of the temperature measurement. Responsible for return control.

FIG. 20 illustrates a tire to be inspected. In general, a tire has a different structure between a contact surface portion and a side surface portion. On the contact surface side, a rubber tread portion 141, an outer cord portion 142,
It has a multilayer structure formed of a steel cord portion 143, an inner cord portion 144, and a rubber / inner film portion 145. The tire has a multi-layered structure formed by an outer rubber portion 145, a cord portion 146, and an inner rubber portion 147 from the outside to the inside on the side surface side. In such a multilayer structure, the respective layers are strongly bonded and joined.

When such a tire is heated from the inner surface, a temperature distribution appears as the heating energy permeates inward from the inner surface. The temperature distribution is
The thickness and material of the rubber / inner film portion 145 and the inner rubber portion 147
It differs according to the difference in the cross-sectional structure from the surface toward the inside. If there is an air layer below the surface, the air layer has a lower thermal conductivity than rubber, so the heating energy is stored on the surface without penetrating inward, and the surface temperature of the storage is It tends to be higher than its surroundings.

Temperature distribution detecting method: In addition, an outer cord portion 142, a steel cord portion 143,
Inner code part 144, code part 145, code part 146
Is formed of synthetic fibers and has a different thermal conductivity from rubber, so that the surface temperature tends to be different in a portion where the inner membrane covering those cords is thinner than in other portions. The temperature distribution reflecting such a difference tendency corresponds to the presence, location, and size of a defective portion of the tire.

The heating energy for the tire is locally or entirely applied to the tire surface (inner surface, outer surface, both surfaces) as shown in the above-described embodiments. FIGS. 17A and 17B show changes in the surface temperature of the inspected tire 7 due to a failure event. FIG. 3A shows a change in the surface temperature when only the surface is heated, and FIG. 3B shows a change in the surface temperature when the entire body is uniformly heated and then locally cooled.

As shown in FIG. 17A, void 1
On the tire inner surface in the region where 51 exists, the amount of input energy 152 reflected and released by heating is large, and the surface temperature in that region appears high (155). In the cooling-type embodiment, as shown in FIG. 17B, of the heat input energy 153 stored inside by heating, the emission energy from the inner surface is the inner surface of the tire in the region where the void 151 exists. And the surface temperature in that region is low (1
56) appears.

When the heating time is prolonged, the heating energy penetrates into the inside and becomes saturated, so that there is no difference in surface temperature. It is important that subsurface defects be detected within a reasonable time after heat input and incidence of heating energy. Immediately after the stop of the input of the heating energy, immediately after the stop, the heat flow in the temperature change portion generated in the narrow area of the surface is diffused, and the temperature difference from the defective portion is reduced. It is important that the small voids 157 shown in FIG. 20 be detected within an appropriate time after heat input and incidence of heating energy.

As described above, it is effective to heat the tire inner surface in a short time and detect the temperature distribution immediately after heating the inner surface of the tire in order to detect a trouble event on the inner surface of the tire or in the vicinity of the inner surface. After heating the tire surface to a sufficiently constant temperature, cooling it locally or simultaneously at the same time, and detecting the surface temperature distribution immediately after the cooling is effective for finding defective parts. is there. In this case, it is particularly preferable that the detection of the defective portion is also performed within an appropriate time after cooling.

It is apparent that the variety of heat input methods such as local heating / cooling and global heating / cooling can be achieved by the above-described devices. The devices shown in FIGS. 2 to 4 also allow for the continuous detection of defective parts. It is also possible to perform continuous heating on the inner surface of the tire and local heating while changing the heating position, and continuously detect a temperature change caused by heating.

The apparatus shown in FIG. 3 detects a malfunction by simultaneously heating the entire inner surface of the tire and immediately after that, detecting the surface temperature distribution over the entire inner surface of the tire. The device shown in FIG. 4 has a cooling device placed near a surface temperature detection sensor, and detects a change in surface temperature while locally cooling the inner surface of the tire, thereby enabling detection of a malfunction event. .

In order to detect the surface temperature of the entire inner surface of the tire, a temperature change is applied to the entire inner surface of the tire by a temperature change applying device, and the tire to be inspected is positioned at a temperature change detecting position of the temperature change detecting device. It is important that the temperature change detection sensor is point-like, linear, or planar, and when temperature information on the entire inner surface cannot be obtained at the same time, the movement of only that sensor and the tire It is necessary to measure the temperature change of the entire inner surface by both of the movements, and such a need is satisfied by the tire installation table 1 shown in FIG.

The temperature change imparting device shown in FIG. 6 can heat the entire area in a linear manner in a cross section perpendicular to the rotation direction of the tire, and by rotating the tire or the temperature change imparting device, the circle of the tire can be heated. Since a rapid heat flow can be generated in the entire circumferential direction and a sudden change in the surface temperature can be generated, a difference in properties of the tire on the surface and in the vicinity thereof can be remarkably detected. Furthermore, by condensing the heating energy with a reflecting mirror and a lens, even for tires of different diameters, the fluctuation of the applied energy of temperature change is reduced on the inner surface, and a good and stable condition for detecting the defect is obtained. Can be maintained.

The temperature change applying device shown in FIG. 7 can simultaneously apply heating energy to the entire inner surface of the tire, eliminating the need to rotate the tire and the device, simplifying the inspection device and reducing the inspection speed. It is particularly preferable in terms of improvement.

The tire inspection apparatus shown in FIG. 8 uses hot air or cold air as a heating source. By blowing out hot air, the same operation as the apparatus shown in FIG. 6 can be obtained. By blowing cool air in combination with the device to be provided, a local temperature change can be given on the inner surface of the tire, and the same operation and effect as the device shown in FIG. 6 can be obtained. Further, since the cooling air blowing nozzle is only the guide plate, the size of the device can be reduced.

The temperature change detecting device shown in FIG. 9 can detect a temperature change in a linear portion of a cross section orthogonal to the circumferential direction of the tire. FIG. 18 shows a detection signal on which appropriate signal processing has been performed. The horizontal axis indicates the rotational angular position of the torus portion. The device shown in FIG. 9, which can be downsized, is located inside the tire, and by rotating the tire or scanning the inside of the tire along the inner circumference of the tire, the entire area of the inner surface is subjected to a trouble event. Discovery is possible.

The temperature change detecting device shown in FIG. 10 can detect a belt-like temperature change in a cross section of a tire. This device can detect a temperature change faster than the device shown in FIG.

The temperature change detecting device shown in FIG. 11 can detect a temperature change in a section on the inner surface of the tire without rotating the tire. The temperature change can be detected even faster than in the device shown in FIG. In this case, by applying an extremely wide-angle lens, it is possible to detect a temperature change over the entire side and bottom surfaces by rotating the tire or rotating the device.

By using the reflecting mirrors shown in FIGS. 12 and 13, by rotating the tire or by rotating the device, it is possible to detect a temperature change over the entire inner surface of the tire. In this case, a relatively large infrared camera can detect a narrow area of the tire.

The temperature change detecting device shown in FIG. 14 changes the observation direction by using a conical reflection mirror and an infrared camera having the same configuration as the device shown in FIG.
It is possible to detect mainly a temperature change over the entire bottom surface over the tire inner circumference. It is preferable that the reflection mirrors constituting the plurality of devices shown in FIGS. 9, 10, 12, 13, and 14 include a cooling device. The cooling can reduce the heat energy radiated from the reflection mirror and improve the detection resolution of the change in the inner surface temperature of the tire.

The scanning mechanism 4 is important for positioning the focal position of the lens, positioning the reflection mirror, adjusting the relative distance between them and the inner surface of the tire, and controlling the position described above. The adjustment is also important in ensuring the uniformity of the heat input energy, and is ultimately particularly important for improving the detection resolution of the temperature change. Furthermore, it is important for positioning a component such as a reflection mirror in a narrow space.

As described above, the cross section of the tire differs depending on the position and location. Even if heating energy is input uniformly to the inner surface, the surface temperature is not uniform as shown in FIG. The signal processing device 5 has a function of extracting a difference between the surface temperature distribution detected by the relationship between the type of the tire and the surface temperature applying device and the temperature distribution in the case of including a tire trouble such as a void. ing.

Such a difference is shown in FIGS. 19 (a) and (b).
Has been removed, as shown in FIG. 19 (a)
Indicates two scanning lines A and B whose temperatures are detected,
A void 157 exists on the scanning line A. FIG.
(B) shows temperature distribution curves TA and TB on the scanning lines A and B. The temperature distribution curves TA and TB are stored in the memory device 1
29. In the figure, a difference (TA-TB) as a signal processing result is written.

The expanded portion of the difference curve indicates the presence of a void, and the abscissa interval of the expanded portion indicates the size of the void in that direction and the position of occurrence. The information and data obtained by the two-dimensional infrared sensor take the average value of the data in the sectioned area, so that the temperature change portion of the two-dimensional distribution can be detected by calculation. In addition to performing the various controls described above, the control device can also control the operation of the alignment table, its rotation speed, its stop, and control of the heat input speed of energy related to the rotation speed of the tire.

FIG. 21 shows another embodiment of the tire inspection apparatus according to the present invention. The tire inspection device is
As in the plural embodiments described above, the optical device includes a temperature change detecting device and a temperature change providing device. In this embodiment, as shown in FIG. 3, the temperature change providing device includes a temperature change providing light source device. The temperature change providing light source device 211 includes an optical heat ray emission source. The optical heat radiation source includes a heat radiation guide fiber 2
Twelve ends are connected. Heat ray guide fiber 212
Is connected to the collimator 213.

The collimator 213 generates a plurality of heat fluxes radiated in a cone shape from the end face of the heat guide fiber 212.
It is converted into a hot beam of a certain effective diameter using a lens.
A transmission type reflection mirror 214 is arranged on the optical axis of the collimator 213. The optical axis is rotated by 90 degrees and heads toward the rotary reflection mirror 215. The rotary reflection mirror 215 is attached to an output shaft 217 of the drive motor 216.

The reflection surface (plane) of the rotary reflection mirror 215
Has an angle of 45 degrees with respect to the rotation axis of the output shaft 217. The main optical axis 218 that has been rotationally converted by the transmission-type reflecting mirror 214 substantially coincides with the rotation axis of the output shaft 217. A set prism 219 is attached to the rotation type reflection mirror 215 in the center region thereof. The set prism 219 has a double reflection function of shifting the position of the main optical axis 218 to the shift optical axis 220. Shift optical axis 22
0 is parallel to the main optical axis 218. Instead of the set prism 219, a set reflecting mirror can be used.

The shift optical axis 220 is connected to the rotary reflection mirror 2.
Fifteen planes undergo a 90-degree rotation conversion, and the incident optical axis 2
21. The incident optical axis 221 is
Incident on the inner (peripheral) surface at a substantially right angle. The point of incidence is P
Indicated by A radiation point P ′ is taken at a position away from the incident point P by a distance ΔR. A line segment connecting the point P and the point P ′ is a portion of a substantially circular arc 222 where a plane including the center line of the tire 7 to be inspected and the inner peripheral surface of the tire 7 intersect. The center point of the rotary reflecting mirror 215 is on the circumferential center line of the tire 7 to be inspected, and coincides with the approximate center point of one specific circular arc 222.

Some of the heat rays radiated from the radiation point P ′
It is on the return optical axis 223 parallel to the incident optical axis 221. The return optical axis 223 passes through the center point of the rotary reflecting mirror 215. The return optical axis 223 receives the 90-degree rotation conversion and is converted into the main optical axis 224. The return main optical axis 224 coincides with the main optical axis 218.

The return main optical axis 224 is connected to the transmission type reflection mirror 214.
And enters the infrared sensor 225. A condenser lens 226 is arranged in front of the infrared sensor 225. The light reception signal of the infrared sensor 225 is
7 is amplified. As the infrared sensor 225, a detection device such as a thermal bolometer, a pyroelectric detector, a quantum photoconductive device, a photovoltaic device, or an impurity device can be used as a cooling type or an uncooling type. For the condenser lens 226, a material that can obtain a practical transmittance with respect to infrared rays emitted from the tire 7 to be inspected is used. Such a material contains Ge and Si.

The receiver 228 for receiving the drive motor 216 and the infrared sensor 225 is mounted on a single frame 229. The frame 229 is attached to the mounting seat 127 of FIG.
It is fixed and attached to. The reference heat source 231 is attached to the frame 229. The reference heat source 231 emits a reference heat ray 232. The reference heating wire 232 normally enters the center point of the rotary reflecting mirror 215, and can maintain a constant temperature near the center point.

The filter 2 is located in front of the condenser lens 226.
33 are arranged. The filter 233 does not transmit the optical heat ray emitted from the temperature change providing light source device 211, but emits the heat ray emitted from the tire 7 to be inspected, the reference heat source 231.
Is selected so as to transmit the reference heat ray 232 emitted by the.

FIG. 22 shows an embodiment of the control device 6 corresponding to the device of FIG. This control device 6 differs from the control device of FIG. 1 in that a reference heat source 231 is added as a device connected to the control device 6. In FIG. 22, the tire installation table 1 is omitted. When the temperature corresponding to the signal output from the temperature change detection device 3 sharply decreases, the heating heat beam deviates from the tire 7 to be inspected. During such a period in which the detected temperature is low, the control device 6 stops emitting the heating heat ray from the temperature change providing light source device 211.

The heat ray beam having passed through the collimator 213 is divided into a main optical axis 218, a shift optical axis 220, and an incident optical axis 221.
And enters the point P on the inner surface of the tire 7 to be inspected.
In the vicinity of the point P receiving such an incident beam, its temperature rises rapidly. The heat input energy at point P quickly diffuses around it. The diffusion includes in-plane diffusion and in-plane diffusion. The temperature at the point P ′ near the point P rises rapidly with a slight delay from the temperature rise at the point P. Before the point P receives heat, the temperature at the point P is already increasing, and at the same time, the temperature at the point P 'is also increasing.

At the time when the heating beam enters the point P, the point P '
The radiant heat rays radiated from the optical axis pass through the return optical axis 223, the return main optical axis 224, and the main optical axis 218,
4, the light is condensed by the condensing lens 226, and is incident on the infrared sensor 225. The electric signal generated by the infrared sensor 225, amplified by the preamplifier 227, and input to the control device 6 is proportional to the temperature at the point P 'at that moment.

If the rotary reflection mirror 215 is rotating, the minute region where the temperature is rapidly increased due to the continuous heating is moving at a constant speed with respect to the temperature detection system. Radiation point P 'included in such a moving micro area
Is constant if the inner surface of the inspected tire 7 is uniform. The actual inner surface of the tire 7 to be inspected is not a perfect cylindrical surface but a deformed cylindrical surface. If the plurality of tires 7 to be inspected are the same, the temperature pattern on one general arc 222 is the same for the plurality of tires 7 to be inspected. In the present embodiment in which laser heating is performed, the temperature rises rapidly and locally.

A rapid rise in temperature locally means a rapid fall in temperature. Since the region of such a local temperature rise is normally observed,
It is hardly affected by the outside world, and the temperature (not the absolute value) of the local area can be accurately measured. If there is an abnormality on the inner surface of the tire 7 to be inspected, a rapid change in temperature occurs in a local area. Since the absolute value of the width of the rapid change is large, the present embodiment enables highly accurate defect detection.

FIG. 24 exemplifies a temperature change detected by the temperature change detecting device. This temperature change is a temperature change on the inner surface of the tire 7 to be inspected. FIG. 23 shows the setting of the coordinate system of the inner surface of the tire 7 to be inspected. If the coordinates in the circumferential direction are represented by θ and the angle around the circumferential center line of the tire 7 to be inspected is represented by φ, aφ (= R) is a plane including the center axis of the tire 7 to be inspected. The coordinates of a substantially circular arc which is a cross line on the inner surface of the tire 7 to be inspected are shown.

FIG. 24 shows the temperature distribution in the R direction at a certain angle θ with respect to the inner surface of the tire 7 to be inspected. The range of R is approximately 120 degrees with respect to φ. At the coordinate position of θ, there is one defective portion. The defective portion appears as a portion 251 where the temperature is rapidly increased.

FIGS. 25A, 25B, and 25C show a method in which the signal processing device 5 performs difference processing on the temperature distribution in the R direction. FIG. 25A shows a temperature distribution Tθ1 in the R direction at a position where θ is θ1. FIG. 25B shows a temperature distribution Tθ2 in the R direction at a position where θ is θ2. FIG. 25C shows ΔTθ1. ΔTθ1 = Tθ2−Tθ1. Here, θ2 is a position coordinate near θ1.

If there is no defect in the inspected tire 7, since the temperature distribution is the same at both positions θ1 and θ2 in the vicinity, ΔTθ1 is almost zero. If there is a defect shown in FIG. 24, the electric signal appears as a non-zero value at the position R where the defect exists. The value of θ is updated, and the control device 6 rotates the tire 7 to be inspected by Δθ. next,
The difference ΔTθ2 between Tθ3 and Tθ2 is calculated. In this way, the difference is obtained for the entire circumference of the tire 7 to be inspected, and the range S (R, θ) on the two-dimensional plane where the defect is present is specified.

FIGS. 26A, 26B and 26C show a method in which the signal processing device 5 performs a difference process on the temperature distribution in the θ direction. FIG. 26A shows a temperature distribution TR1 in the θ direction at a position where R is R1. FIG. 26B shows a temperature distribution TR2 in the θ direction at a position where R is R2. FIG. 26C shows ΔTR1. ΔTR1
= TR2-TR1. Here, R2 is a position coordinate near R1.

If there is no defect in the tire 7 to be inspected, ΔTR1 is almost zero because the temperature distribution is the same at both positions R1 and R2 in the vicinity. If there is a defect in the θ direction, the electric signal appears as a non-zero value at the position R where the defect exists. The value of R is updated, and the control device 6 rotates the rotary reflecting mirror 215 by ΔR. next,
The difference ΔTR2 between TR3 and TR2 is calculated. In this way, the difference is obtained for the entire region in the R direction, and the range S (R, θ) on the two-dimensional plane where a defect exists is specified.

As shown in FIG. 25B, even when there is no defective portion, a temperature change appears. This temperature change is specific to the tire 7 to be inspected. By taking the difference between the two adjacent points, it is possible to remove a temperature change inherent to the tire 7 to be inspected. Further, FIG.
As shown in (1), a unique temperature change also appears in the R direction. By calculating the difference between two adjacent points in the R direction, it is possible to remove a unique temperature change. By taking the difference in the R direction and the θ direction, the influence of the difference in the surface temperature distribution specific to the tire type can be further reduced, so that a more correct judgment can be made than the judgment based on one difference. Can be.

FIGS. 27 and 28 show two heating methods based on the difference in heat conduction. As shown in FIG. 27, the heat uniformly supplied to the surface from the outside has no heat conduction along the surface, and only heat conduction 252 toward the deep portion occurs. If the void 253 is partially present, the heat distribution is
A symmetrical heat distribution as shown in FIG. Such a heat input method is called an out-of-plane heating method. As shown in FIG. 28, heat locally supplied to the surface from the outside causes both heat conduction 254 along the surface and heat conduction 255 toward the depth. If there is a crack 256 in a part, detour heat conduction further appears, and the heat distribution shows an asymmetric heat distribution as shown in FIG. Such a heat input method is called an in-plane heating method.

It is shown in FIGS. 29 to 31 that the present invention can be applied to both the out-of-plane heating and the in-plane heating. As shown in FIG. 29 (a), since the heating input point P moves in the direction of the arrow at a low speed, the measuring point P ′ is a heat input point even if there is no defect and there is no inherent asymmetry on the heating surface. It is shifted by ΔL from P in the moving direction, and asymmetry appears in the surface temperature distribution in the R direction. This temperature distribution shows asymmetry showing the highest value immediately after the passage of the heating point P.

FIG. 30 shows a case where a void 253 is present. The measured heat distribution shows a heat distribution 258 in which the amount of heat conduction is larger in the rear in the moving direction and the temperature is higher than the heat distribution 257 without voids. This temperature distribution shows asymmetry showing the highest value at a position immediately after the passage of the heating point P, and a difference in ΔT occurs in the peak value comparison, so that the temperature rises as a whole. Crack 256 as shown in FIG.
When there is, in-plane heating is performed, and a temperature distribution 259 that is higher than the temperature distribution when there is no crack ahead in the moving direction appears. In-plane heating is performed, and the temperature change at a position after the heating point P is a change in which the temperature increases if there is a crack immediately before the heating point, and if there is a crack immediately after the heating point, the temperature is increased. It is a change that becomes lower. As described above, by continuously detecting the temperature change at a fixed position close to the heating point, peeling and cracking can be simultaneously detected in the same inspection process.

[0135]

The tire inspection apparatus according to the present invention can effectively detect a defect of a tire and can detect a defect at a high speed. Further, the type of the defect can be determined.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of a tire inspection device according to the present invention.

FIG. 2 is an axial projection view showing an embodiment of the tire inspection device according to the present invention.

FIG. 3 is an axial projection view showing another embodiment of the tire inspection device according to the present invention.

FIG. 4 is an axial projection view showing still another embodiment of the tire inspection device according to the present invention.

FIG. 5 is an axial projection view showing an embodiment of the tire installation table.

FIG. 6 is a sectional view showing an embodiment of a temperature change applying device.

FIG. 7 is a sectional view showing another embodiment of the temperature change applying device.

FIG. 8 is a sectional view showing still another embodiment of the temperature change applying device.

FIG. 9 is a projection view of the axis showing the embodiment of the temperature change detecting device.

FIG. 10 is an axial projection view showing another embodiment of the temperature change detecting device.

FIG. 11 is an axial projection view showing still another embodiment of the temperature change detecting device.

FIG. 12 is an axial projection view showing still another embodiment of the temperature change detecting device.

FIG. 13 is an axial projection view showing still another embodiment of the temperature change detecting device.

FIG. 14 is an axial projection view showing still another embodiment of the temperature change detection device.

FIG. 15 is an axial projection view showing still another embodiment of the scanning mechanism.

FIG. 16 is a circuit block diagram showing an embodiment of a circuit for giving and detecting a temperature change.

FIGS. 17A and 17B are graphs showing temperature changes.

FIG. 18 is a graph showing another temperature change.

FIGS. 19 (a) and 19 (b) are radial projection diagrams and graphs showing the occurrence of tire failure and temperature changes.

FIG. 20 is a sectional view showing a multilayer structure of a tire.

FIG. 21 is an axial projection view showing still another embodiment of the tire inspection device according to the present invention.

FIG. 22 is a circuit block diagram showing another embodiment of the control system.

FIG. 23 is an axial projection view showing a coordinate system of the tire.

FIG. 24 is a graph showing a temperature distribution.

FIGS. 25 (a), (b) and (c) are graphs each showing a temperature distribution.

26 (a), 26 (b) and 26 (c) are graphs showing other temperature distributions, respectively.

FIGS. 27 (a) and 27 (b) are analysis diagrams showing a correlation of appearance of a temperature change.

FIGS. 28 (a) and 28 (b) are analysis diagrams showing correlations of other appearances of a temperature change.

FIGS. 29 (a) and 29 (b) are analysis diagrams showing a correlation of still another appearance of a temperature change.

FIGS. 30 (a) and 30 (b) are analysis diagrams showing a correlation of still another appearance of a temperature change.

FIGS. 31 (a) and 31 (b) are analysis diagrams showing a correlation of still another appearance of a temperature change.

[Explanation of symbols]

2. Temperature change imparting device 3. Temperature change detection device 4. Scanning mechanism 7. Tire to be inspected 41, 211 Heat ray radiator (heating device) 42 Heating element (heating device) 44 Cylindrical circular lens (optical device) 51, cold air (cooling device) 54, air introduction tube (cooling device) 63 ', mirror swinging motor (optical device, optical system) 64, scanning type detection mirror (optical device, optical system) 67, 226: condenser lens (optical device, optical system) 66, 225: spot type infrared sensor (optical device, optical system) 82: dimensional infrared sensor 82 (optical device, optical system) 83: spherical lens (optical device, optical device) Optical system) 91: Transmission type reflection mirror (optical device, optical system) 111: Total reflection mirror (optical device, optical system) 112: Conical surface (optical device, optical system) 115: Cone-shaped reflective surface (optical) Equipment, optical system) 151, 157: void (defective part)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masashi Okamura 6-16-1, Hinoshima Enouracho, Shimonoseki City, Yamaguchi Prefecture Inside the Shimonoseki Shipyard, Mitsubishi Heavy Industries, Ltd. No. 19 Takahashi Engineering Co., Ltd. (72) Inventor Hiroshi Yatabe 2-chome, Arai-cho, Niihama, Takasago City, Hyogo Pref. No. 19 Takahashi Engineering Co., Ltd. DA24 EA06 EA08 EB02 FA04 FA10 GA05 GA07 HA08 HA16

Claims (28)

[Claims] 1. A scanning mechanism for appropriately positioning a temperature change detecting device with respect to a tire to be inspected, a temperature change applying device for generating a temperature change in the tire to be inspected, and A tire inspection device comprising: an optical device for optically detecting emitted heat rays. 2. The tire inspection device according to claim 1, wherein the surface of the tire to be inspected is an inner surface. 3. The tire inspection device according to claim 1, wherein the temperature change applying device is disposed on an inner surface of the tire to be inspected. 4. The tire inspection device according to claim 3, wherein the temperature change applying device is a heating device. 5. The tire inspection device according to claim 3, wherein the temperature change applying device changes a heating position while partially heating the tire to be inspected. 6. The tire inspection device according to claim 5, wherein the optical device changes a detection position while partially detecting heat radiated from a surface of the tire to be inspected. 7. The tire inspection apparatus according to claim 6, wherein the change of the detection position is continuous. 8. The tire inspection device according to claim 1, wherein the temperature change applying device heats the entire tire to be inspected. 9. The tire inspection device according to claim 3, wherein the temperature change applying device is a cooling device. 10. The tire inspection device according to claim 1, wherein the light receiving surface of the optical device is arranged on an inner surface side of the tire to be inspected. 11. The tire inspection apparatus according to claim 1, wherein the optical device is positioned on an inner surface side of the tire to be inspected by a three-dimensional scanning mechanism. 12. The tire according to claim 11, wherein the optical device is disposed at a position deviated from a center position of the tire to be inspected, and partially detects heat radiated from a surface of the tire to be inspected. A tire inspection device wherein a detection position changes. 13. The tire inspection device according to claim 12, wherein the detection position is a linear region. 14. The tire inspection apparatus according to claim 12, wherein the detection position is a planar area. 15. The optical device according to claim 11, wherein the optical device is disposed at a central position of the tire to be inspected, detects heat radiated from a surface of the tire to be inspected entirely, and its detection position does not change. A tire inspection device characterized by the above-mentioned. 16. The mirror according to claim 1, wherein the optical device comprises: a light receiving device; and a mirror device interposed between the heat ray radiating region on the inner surface of the tire to be inspected and the light receiving device. A tire inspection device, characterized in that the device comprises a rotating device for rotating the reflecting surface. 17. The optical device according to claim 1, wherein the optical device comprises: a light receiving device; and a mirror device interposed between the heat ray radiating region on the inner surface of the tire to be inspected and the light receiving device. A tire inspection device, wherein the mirror of the device has a reflecting surface, and the reflecting surface is a conical surface. 18. A method for testing a tire formed from an inner layer and an outer layer having a higher thermal conductivity than the inner layer, the method comprising: causing a temperature change in the inner layer; Detecting the heat dose of heat rays radiated from the inner surface of the inner layer. 19. A step for heating a first localized area of the tire surface, and measuring radiation emitted from a second localized area of the tire surface remote from the first localized area. And a step of performing a first scan for heating the first local area and a second scan for measurement of the second local area to determine a failure of the tire. 20. The tire inspection method according to claim 19, wherein the two scans are continuous. 21. The tire inspection method according to claim 20, wherein the two scans are performed at a synchronized scanning speed. 22. The tire inspection method according to claim 20, wherein the heating is performed by a laser. 23. The tire inspection method according to claim 22, wherein the laser and the radiated light optically pass on the same optical axis. 24. The tire inspection method according to claim 20, wherein the two scans are performed two-dimensionally. 25. The two-dimensional scan according to claim 24, wherein one-dimensional scan of the two-dimensional scan is performed by rotation of an optical axis of the laser, and another one-dimensional scan of the two-dimensional scan is performed by rotation of a tire. A tire inspection method, characterized in that: 26. The tire inspection method according to claim 20, wherein a separation distance between the first local area and the second local area is variable. 27. The tire inspection method according to claim 20, wherein a difference between measurement values at two different positions by the measurement of the second local region is obtained. 28. The tire inspection method according to claim 27, wherein the difference is obtained two-dimensionally.