JP2009250963A - System and method for measuring internal shape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal shape measuring system which can be mounted on vehicles to easily measure an internal shape of a pneumatic tire, and the measuring method. <P>SOLUTION: This invented internal shape measuring system is to measure an internal shape, that is, an inner aspect shape of the pneumatic tire, including a marker 20 formed on at least a part of the inner aspect, two or more cameras 30 for filming the marker 20 to output image data of the filmed marker 20, and deformation volume calculating section 70 which uses each of the image data respectively output from those two or more cameras 30 to calculate deformation volume of the inner aspect. It is characterized by that the marker 20 is plurally-formed at regular intervals, and plural cameras 30 are mounted on a rim wheel 12 with the pneumatic tire 10 attached, while each of these cameras 30 is arranged in different position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an inner surface shape measuring system and an inner surface shape measuring method for measuring an inner surface shape which is a shape of an inner surface of a pneumatic tire.

  Conventionally, the shape of the inner surface of a pneumatic tire deformed due to contact with the road surface or a load applied to the pneumatic tire, specifically, the shape of the inner surface of the tread portion or sidewall portion (hereinafter referred to as the inner surface shape). ) Has been realized.

For example, an inner surface shape measurement system using a laser displacement meter is known (see Patent Document 1). The inner surface shape measurement system includes a rim portion that engages with a bead portion of a pneumatic tire. The laser displacement meter is disposed at a certain distance from the inner surface of the pneumatic tire engaged with the rim portion (for example, the inner surface of the tread portion), and the distance from the inner surface of the pneumatic tire, that is, Measure the displacement of the inner surface shape.
Japanese Patent Laid-Open No. 11-23237 (FIG. 3)

  However, the above-described conventional inner surface shape measuring system has the following problems. That is, the conventional inner surface shape measuring system using a laser displacement meter has a problem that it cannot be mounted on a vehicle because of its large size and complicated structure.

  Therefore, the present invention has been made in view of such a situation, and can be mounted on a vehicle and can easily measure the inner surface shape of a pneumatic tire and the inner surface shape measurement system. It aims to provide a method.

  In order to solve the above-described problems, the present invention has the following features. First, the invention according to the first feature is an inner surface shape measuring system (an inner surface shape measuring system) that measures the inner surface shape that is the shape of the inner surface (inner surface 11A or inner surface 16A) of a pneumatic tire (pneumatic tire 10). 1) The marker (marker 20) formed on at least a part of the inner surface and the marker are photographed, and image data of the photographed marker (normal two-dimensional data or deformation two-dimensional data) is output. Using a plurality of cameras (camera 30 (first camera 30A and second camera 30B)) and image data respectively output from the plurality of cameras, a deformation amount calculation unit (deformation) that calculates the deformation amount of the inner surface A rim wheel (rim wheel 1) in which a plurality of markers are formed with a predetermined interval, and a plurality of cameras are assembled with pneumatic tires. Together is attached to), each camera is summarized in that disposed in different positions.

  According to such a feature, the marker is formed on the inner surface, and a plurality of cameras are attached to the rim wheel, so that the size is significantly smaller than that of an inner surface shape measurement system using a conventional laser displacement meter. In addition, since the structure is simple, it can be mounted on a vehicle.

  In addition, the deformation amount calculation unit calculates the deformation amount of the inner surface using image data taken by a plurality of cameras, so that the pneumatic tire can be compared with an inner surface shape measurement system using a conventional laser displacement meter. The inner surface shape can be measured easily and accurately.

  Another aspect of the invention is characterized by further including an illumination unit (illumination unit 40) that illuminates the inner surface on which the marker is formed.

  The gist of the invention according to another feature is that the marker is a plurality of dots (circular shape) along the tread width direction and the tire circumferential direction.

  The gist of another aspect of the invention is that a plurality of cameras are disposed at different positions along the tire circumferential direction.

  The gist of the invention relating to other features is that a plurality of adjacent cameras are arranged in a region having an angle with the center of the pneumatic tire as a vertex within 120 degrees in a side view of the pneumatic tire.

  The invention according to another feature receives a wireless transmission unit (wireless transmission unit 50) that transmits image data as a wireless signal, and a wireless signal transmitted from the wireless transmission unit, and outputs the image data to a deformation amount calculation unit. The gist is to further include a wireless receiver (wireless receiver 60).

  The invention according to another feature is an inner surface shape measuring method for measuring an inner surface shape which is a shape of an inner surface of a pneumatic tire, using a plurality of cameras attached to a rim wheel on which the pneumatic tire is assembled, A step of photographing a marker formed on at least a part of the inner surface, and a step of calculating a deformation amount of the inner surface using image data of the marker photographed by a plurality of cameras, wherein the marker has a predetermined interval A gist is that a plurality of cameras are formed and each of the cameras is disposed at a different position.

  According to the present invention, it is possible to provide an inner surface shape measuring system and an inner surface shape measuring method that can be mounted on a vehicle and can easily measure the inner surface shape of a pneumatic tire.

  Next, an example of an inner surface shape measuring system and an inner surface shape measuring method according to the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions are different from actual ones. Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

(Configuration of inner surface shape measurement system)
First, the configuration of the inner surface shape measurement system according to the present invention will be described with reference to FIGS. FIG. 1 is a partial cross-sectional perspective view showing a pneumatic tire and a rim wheel to which an inner surface shape measuring system according to the present embodiment is mounted, and FIG. 2 is a diagram illustrating the inner surface shape measuring system according to the present embodiment. 3 is an exploded perspective view showing the pneumatic tire and the rim wheel, and FIG. 3 is a side sectional view showing the pneumatic tire and the rim wheel to which the inner surface shape measurement system according to the present embodiment is mounted. These are block diagrams which show the inner surface shape measuring system which concerns on this Embodiment.

  Note that the pneumatic tire and the rim wheel according to the present embodiment are a heavy load tire and a heavy load rim wheel mounted on a heavy load vehicle such as a construction vehicle.

  As shown in FIGS. 1 to 4, the inner surface shape measurement system 1 has the shape of the inner surface of the pneumatic tire 10, specifically, the inner surface 11 </ b> A of the tread portion 11 that contacts the road surface of the pneumatic tire 10. The inner surface shape is measured.

  The inner surface shape measurement system 1 includes a marker 20, a plurality of cameras 30, an illumination unit 40, a wireless transmission unit 50, a wireless reception unit 60, and a deformation amount calculation unit 70 (see FIG. 4). .

  The marker 20 is formed on at least a part of the inner surface 11 </ b> A of the tread portion 11 in the pneumatic tire 10. The marker 20 does not affect the deformation of the tread portion 11.

  Specifically, the marker 20 is formed with a plurality of dots 21 having a predetermined interval and having a circular shape. The plurality of dots 21 are arranged along the tread width direction and the tire circumferential direction. That is, the adjacent dots 21 have a gap G1 in the tire circumferential direction and a gap G2 in the tread width direction.

  Note that the plurality of dots 21 do not necessarily have to be circular, and may be, for example, a triangular shape, a rectangular shape, or a cross shape in which lines intersect, and the marker 20 may be formed in a lattice shape. Of course. The plurality of dots 21 may all be the same, or may be different in size, chromaticity, saturation, brightness, and the like.

  The plurality of cameras 30 includes a first camera 30A and a second camera 30B. The plurality of cameras 30 captures the marker 20 and outputs image data (stereo image) of the captured marker 20. The plurality of cameras 30 are attached to the rim wheel 12 that is assembled to the pneumatic tire 10. The rim wheel 12 has a main body rim 12A and a rim sheet 12B attached to the main body rim 12A (a so-called split rim).

  The first camera 30A and the second camera 30B are arranged at different positions. Specifically, the first camera 30A and the second camera 30B are disposed at different positions along the tire circumferential direction. Further, the adjacent first camera 30A and second camera 30B are arranged in a region where the angle (α) with the center C of the pneumatic tire 10 as the apex is within 120 degrees in a side view of the pneumatic tire 10. It is preferable to be provided (see FIG. 3). If the angle (α) is greater than 120 degrees, the first camera 30A and the second camera 30B may not be able to photograph the contact surface where the tread portion 11 is in contact with the road surface.

  As described above, the image data of the marker 20 photographed by the first camera 30A and the image data of the marker 20 photographed by the second camera 30B are photographed from different angles. In the first camera 30A, normal two-dimensional data (see FIG. 6A) that is image data of the marker 20 in a normal state in which the tread portion 11 is not deformed while the vehicle is traveling, and the tread portion 11 is deformed. Two-dimensional data at the time of deformation (see FIG. 6B) which is image data of the deformed marker 20 is photographed. The second camera 30B has normal two-dimensional data (see FIG. 7A) that is image data of the marker 20 in the normal state, and two-dimensional data at deformation that is the image data of the marker 20 in the deformed state (FIG. 7). (B) is taken.

  The illumination unit 40 illuminates the inner surface 11A on which the markers 20 are formed so that the plurality of cameras 30 can easily photograph the markers 20. The illumination unit 40 is attached to the rim wheel 12 positioned on the inner side in the tire radial direction facing the marker 20 formed on the inner side surface 11A.

  The wireless transmission unit 50 is provided in the internal space 13 between the pneumatic tire 10 and the rim wheel 12. The wireless transmission unit 50 transmits image data captured by a plurality of cameras 30 as a wireless signal. In addition, the wireless transmission part 50 should just be provided in internal space, for example, may be provided integrally with the some camera 30. FIG.

  The wireless receiver 60 is provided outside the pneumatic tire 10 (for example, the deformation measuring device 100). The wireless reception unit 60 receives the wireless signal transmitted from the wireless transmission unit 50 and outputs the image data to the deformation amount calculation unit 70.

  The deformation amount calculation unit 70 is provided outside the pneumatic tire 10 (for example, the deformation measurement device 100). The deformation amount calculation unit 70 calculates the deformation amount of the inner surface 11 </ b> A of the tread portion 11 using image data output from each of the plurality of cameras 30.

  Specifically, the deformation amount calculation unit 70 obtains normal two-dimensional data (see FIGS. 6A and 7A) captured by the first camera 30A and the second camera 30B, respectively. It is converted into a normal three-dimensional image (see FIG. 8A) which is a three-dimensional image. In addition, the deformation amount calculation unit 70 uses the two-dimensional data at the time of deformation (see FIGS. 6B and 7B) captured by the first camera 30A and the second camera 30B, respectively, as a three-dimensional image. Is converted into a three-dimensional image (see FIG. 8B).

  Then, the deformation amount calculation unit 70 uses the normal three-dimensional image, the deformation three-dimensional image, the deformation amount of the pneumatic tire 10 that can be measured from the outside of the pneumatic tire 10, and the like on the inner surface 11A of the tread portion 11. Calculate the amount of deformation.

  The inner surface shape measurement system 1 includes a display unit that displays normal two-dimensional data, deformation two-dimensional data, normal three-dimensional images, deformation three-dimensional images, and the like, and a memory that stores the data and images. Of course, you may provide the part.

(Inner shape measurement method)
Next, an inner surface shape measuring method for measuring the inner surface shape of a pneumatic tire will be described with reference to FIGS. FIG. 5 is a flowchart showing an inner surface shape measuring method according to the present embodiment, and FIG. 6 is a diagram showing two-dimensional data (normal / deformed) taken by the first camera according to the present embodiment. FIG. 7 is a diagram showing two-dimensional data (normal / deformed) taken by the second camera according to the present embodiment according to the present embodiment, and FIG. 8 is a diagram illustrating the present embodiment. It is a figure which shows the three-dimensional image into which two-dimensional data was converted in the deformation amount calculation part which concerns.

  As shown in FIG. 5, in step 10, the inner surface shape measurement system 1 uses a plurality of cameras 30 (first camera 30 </ b> A and second camera 30 </ b> B) attached to the rim wheel 12 to A marker photographing process is performed for photographing the marker 20 formed on at least a part of the side surface 11A.

  Specifically, the first camera 30A captures the normal two-dimensional data shown in FIG. 6A and the deformation two-dimensional data shown in FIG. 6B. The second camera 30B captures the normal two-dimensional data shown in FIG. 7A and the deformation two-dimensional data shown in FIG. 7B.

  Next, in step 20, the inner surface shape measurement system 1 uses the image data of the marker 20 (that is, normal two-dimensional data and deformation two-dimensional data) captured in the marker imaging step (step 10) as a radio signal. An image data transmission step of transmitting from the internal space 13 to the outside of the pneumatic tire 10 (for example, the deformation measuring device 100) via the wireless transmission unit 50 is performed.

  Next, in step 30, the inner surface shape measurement system 1 performs an image data receiving process of receiving the wireless signal transmitted in the image data transmitting process via the wireless receiving unit 60.

  Next, in Step 40, the inner surface shape measurement system 1 uses the image data received in the image data receiving process, that is, the image data of the marker 20 captured by the plurality of cameras 30, of the inner surface 11 </ b> A of the tread portion 11. A deformation amount calculation step for calculating the deformation amount is performed.

  Specifically, the deformation amount calculation unit 70 obtains normal two-dimensional data (see FIGS. 6A and 7A) captured by the first camera 30A and the second camera 30B, respectively. The image is converted into a normal three-dimensional image shown in FIG. Further, the deformation amount calculation unit 70 converts the two-dimensional data at the time of deformation (see FIGS. 6B and 7B) captured by the first camera 30A and the second camera 30B, respectively, as shown in FIG. It is converted into a three-dimensional image at the time of deformation shown in b).

  The deformation amount calculation unit 70 uses the normal three-dimensional image, the three-dimensional image during deformation, the deformation amount of the pneumatic tire 10 that can be measured from the outside of the pneumatic tire, and the like on the inner side surface 11A of the tread portion 11. Calculate the amount of deformation.

  Finally, in step 50, the inner surface shape measurement system 1 performs a measurement result display process for displaying the deformation amount of the inner surface 11A of the tread portion 11 calculated in the deformation amount calculation process (step 40). In the measurement result display step, not only the deformation amount of the inner side surface 11A of the tread portion 11 is displayed but also normal two-dimensional data, deformation two-dimensional data, normal three-dimensional image, deformation three-dimensional image, and the like. It can also be displayed.

  Here, the inner surface shape measuring method according to the present embodiment includes a marker photographing step (step 10), an image data transmitting step (step 20), an image data receiving step (step 30), a deformation amount calculating step (step 40), Although it has been described that the measurement result display process (step 50) is performed, at least the marker photographing process (step 10) and the deformation amount calculation process (step 40) may be performed. That is, instead of the wireless transmission unit 50 and the wireless reception unit 60, a wired connection may be used.

(Action / Effect)
According to the inner surface shape measurement system 1 (inner surface shape measurement method) according to the present embodiment described above, the marker 20 is formed on the inner surface 11A, and the plurality of cameras 30 are attached to the rim wheel 12. Compared with an inner surface shape measuring system using a conventional laser displacement meter, the size is significantly reduced and the structure is simple, so that it can be mounted on a vehicle. That is, along with being able to attach the inner surface shape measuring system 1 to the vehicle, it is possible to measure the inner surface shape of the pneumatic tire 10 while the vehicle is actually traveling.

  Further, the deformation amount calculation unit 70 calculates the deformation amount of the inner surface 11A using the image data captured by the plurality of cameras 30, so that the air amount measurement unit 70 can be compared with the conventional inner surface shape measurement system using a laser displacement meter. It is possible to easily and accurately measure the inner surface shape of the entering tire.

  In addition, since the illumination unit 40 that illuminates the inner side surface 11A on which the marker 20 is formed is further provided, the deformation amount calculation unit 70 can calculate the deformation amount of the inner side surface 11A using clear image data. The accuracy of measuring the inner surface shape of the pneumatic tire 10 can be increased.

  In addition, since the marker 20 is a dot having a plurality of circular shapes along the tread width direction and the tire circumferential direction, it is more than the other shapes (for example, a triangular shape, a rectangular shape, a cross-like dot or a lattice shape). It becomes easy to form the marker 20 on the inner side surface 11A.

  In addition, by arranging a plurality of cameras 30 (first camera 30A and second camera 30B) at different positions along the tire circumferential direction, it is possible to shoot from different angles, and a pneumatic tire. The deformation of the inner surface shape of 10 can be reliably measured.

  Furthermore, since the wireless transmission unit 50 and the wireless reception unit 60 are further provided, no wiring is required as compared to the wired connection, and the wireless transmission unit 50 can be attached to a traveling vehicle. It becomes possible to measure the inner surface shape of the pneumatic tire 10 inside.

[Other embodiments]
As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention.

  Specifically, in the inner surface shape measuring system 1 and the inner surface shape measuring method, it has been described that the shape of the inner surface 11A of the tread portion 11 in the pneumatic tire 10 is measured. However, the present invention is not limited to this. For example, the shape of the inner side surface 16A of the sidewall portion 16 disposed from the bead portion 15 in contact with the rim wheel 12 to the tread portion 11 may be measured. In this case, the marker 20 is formed on at least a part of the inner side surface 16 </ b> A of the sidewall portion 16 in the pneumatic tire 10.

  The plurality of cameras 30 have been described as being configured by the first camera 30A and the second camera 30B. However, the present invention is not limited to this, and may be configured by three or more cameras. Good.

  Moreover, although the illumination part 40 demonstrated as what illuminates the inner surface 11A of the tread part 11 in which the marker 20 was formed, it is not limited to this, For example, even if the marker 20 accumulates light (self-emission). Of course, it is only necessary that a plurality of cameras 30 can photograph the marker 20.

  Furthermore, although the pneumatic tire 10 and the rim wheel 12 have been described as being attached to the heavy load tire and the heavy load rim wheel, the present invention is not limited thereto, and examples thereof include passenger car tires and passenger car rim wheels. Of course, there is no problem.

  From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

It is a partial cross section perspective view which shows the pneumatic tire and rim wheel with which the inner surface shape measuring system which concerns on this Embodiment was mounted | worn. It is a disassembled perspective view which shows the pneumatic tire and rim wheel with which the inner surface shape measuring system which concerns on this Embodiment was mounted | worn. It is side surface sectional drawing which shows the pneumatic tire and rim wheel with which the inner surface shape measuring system which concerns on this Embodiment was mounted | worn. It is a block diagram which shows the inner surface shape measuring system which concerns on this Embodiment. It is a flowchart which shows the inner surface shape measuring method which concerns on this Embodiment. It is a figure which shows the two-dimensional data (at the time of normal / deformation) image | photographed with the 1st camera which concerns on this Embodiment. It is a figure which shows the two-dimensional data (at the time of normal / deformation) image | photographed with the 2nd camera which concerns on this Embodiment which concerns on this Embodiment. It is a figure which shows the three-dimensional image into which two-dimensional data was converted in the deformation | transformation amount calculation part which concerns on this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Inner surface shape measurement system, 10 ... Pneumatic tire, 11 ... Tread part, 11A ... Inner side surface, 12 ... Rim wheel, 12A ... Main body rim, 12B ... Rim seat, 13 ... Internal space, 15 ... Bead part, 16 ... Side Wall part, 16A ... inner surface, 20 ... marker, 21 ... dot, 30 ... camera, 30A ... first camera, 30B ... second camera, 40 ... illumination part, 50 ... wireless transmission part, 60 ... wireless reception part , 70 ... Deformation amount calculation unit, 100 ... Deformation measuring device

Claims (8)

An inner surface shape measuring system for measuring an inner surface shape which is a shape of an inner surface of a pneumatic tire,
A marker formed on at least a part of the inner surface;
A plurality of cameras that photograph the marker and output image data of the photographed marker;
Using the image data output from each of the plurality of cameras, a deformation amount calculation unit that calculates the deformation amount of the inner surface,
A plurality of the markers are formed with a predetermined interval,
The plurality of cameras are attached to a rim wheel on which the pneumatic tire is assembled, and each of the cameras is an inner surface shape measurement system disposed at a different position.   The inner surface shape measurement system according to claim 1, further comprising an illumination unit that illuminates the inner surface on which the marker is formed.   The inner surface shape measurement system according to claim 1, wherein the marker is a plurality of dots along a tread width direction and a tire circumferential direction.   The inner surface shape measurement system according to claim 3, wherein the dots are circular.   The inner surface shape measurement system according to any one of claims 1 to 4, wherein the plurality of cameras are arranged at different positions along the tire circumferential direction.   The inner surface shape measurement system according to claim 5, wherein the adjacent cameras are disposed in a region having an angle with a center of the pneumatic tire as an apex within 120 degrees in a side view of the pneumatic tire. A wireless transmission unit for transmitting the image data as a wireless signal;
The inner surface shape measurement according to claim 1, further comprising: a wireless reception unit that receives the wireless signal transmitted from the wireless transmission unit and outputs the image data to the deformation amount calculation unit. system. An inner surface shape measuring method for measuring an inner surface shape which is a shape of an inner surface of a pneumatic tire,
Photographing a marker formed on at least a part of the inner surface using a plurality of cameras attached to a rim wheel to which the pneumatic tire is assembled; and
Using the image data of the marker imaged by the plurality of cameras, calculating a deformation amount of the inner surface,
A plurality of the markers are formed with a predetermined interval,
Each of the cameras is an inner surface shape measuring method arranged at a different position.

Images