JP2004101240A - Stacked belt ring inspection method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for surely detecting a very small defect generated in the end face of the stacked belt ring and simultaneously automatically detecting the size of the defect as well. <P>SOLUTION: This inspection device for detecting a defect of the end face of the stacked belt ring includes: a microphotographic camera for imaging the end face of the belt ring and varying the focal distance; and a driving means for moving the microphotographic camera toward the end face of the belt ring. The device further includes: an image processing means for generating three-dimensional image from the imaging data of the microphotographic camera; and a display means for displaying three-dimensional data obtained by relatively circulating and moving the stacked belt ring and the microphotographic camera relatively, and simultaneously moving the focal point of the microscope to image the end face of the belt ring. Thus, the depth and number of defects in the end face of the stacked belt ring can be detected. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for inspecting a laminated belt ring, and is particularly suitable for inspecting and diagnosing an end surface flaw of a laminated belt ring (laminated belt ring) constituting a metal V-belt used in a belt type continuously variable transmission. Method and apparatus.
[0002]
[Prior art]
A metal V-belt used for power transmission in a V-belt type continuously variable transmission or the like is composed of an endless belt-shaped metal ring member and a number of metal element members supported along the metal ring member. And is used to transmit power by being bridged between driven pulleys. The V-groove width of both pulleys can be variably controlled. By variably controlling the V-groove width of both pulleys, the winding radius of the metal V-belt on both pulleys is changed, and the distance between the drive shaft and the driven shaft Can be changed steplessly. The metal ring member is a laminated belt ring that is integrally formed by laminating dozens of thin metal ring sheets and is a direct power transmission member, and thus requires a desired strength and durability. Is done. For this purpose, it is checked for flaws before being incorporated into the transmission. The laminated belt ring is formed by laminating dozens of metal ring sheets each having a thickness of 0.1 to 0.2 mm and a width of 9 to 10 mm, and is an important component. Must be removed, if any. Since a size of several tens of μm has a great influence as a flaw, the ability to detect such a flaw is required.
[0003]
At present, the above-mentioned inspection of the laminated belt ring is performed by an operator looking into an optical microscope and observing a two-dimensional image. The inspection operator distinguishes a normal product and a damaged product from the image of the degree of light reflected on the end face of the laminated belt ring. Scratch on the end face of the laminated belt ring is exactly a depression on the metal surface. Compared to the normal product with a smooth metal surface, the product with a dent in the dent has a light scattering at the surface of the dent, resulting in a different image from the normal product. .
Patent Documents 1 to 4 disclose related examples related to this.
[0004]
[Patent Document 1]
JP-A-5-71934 [Patent Document 2]
JP-A-7-208958 [Patent Document 3]
JP-A-9-304288 [Patent Document 4]
JP 2000-57345 A [0005]
[Problems to be solved by the invention]
However, in the conventional inspection, an inspector looks at a two-dimensional image of an optical microscope obtained by imaging an end face of the laminated belt ring. There is no device capable of inspecting the laminated belt ring of a vehicle for scratches (or dents) in the same time as the inspector in the visual inspection work of the inspector. In addition, in human inspection, since there is an individual difference and an inspection for the presence or absence of a scratch using a two-dimensional image, it is not grasped at the depth of the scratch. That is, there is a problem that it is difficult to say that quality control is sufficiently performed.
[0006]
The present invention has been made in view of the above-mentioned conventional problems, and it is possible to reliably detect even a minute flaw generated on the end face of the laminated belt ring, and also to automatically detect the size of the flaw at the same time. It is an object of the present invention to provide a method and apparatus for inspecting a laminated belt ring.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a method for inspecting a laminated belt ring according to the present invention is directed to a method for inspecting a laminated belt ring by using a three-dimensional image obtained by moving a focal point of a microscope and imaging the end face of the belt ring while moving the belt ring around. It is characterized in that the depth and the size of the flaw on the end face are detected. A plurality of the microscopes can be arranged so that different fields of view are not overlapped in the thickness direction of the end surface of the laminated belt ring, and collectively inspected by moving the belt ring once.
[0008]
The laminated belt ring inspection device according to the present invention is a microscope camera capable of changing the focal length and capable of imaging the belt ring end face, and a driving unit capable of moving at least in the plane direction of the belt ring end face of the microscope camera, Image processing means for generating a three-dimensional image from the image data obtained by the microscope camera, and moving the focal point of the microscope while moving the lamination belt ring and the microscope camera relatively around to obtain an image of the belt ring end face. And a display means for displaying a three-dimensional image. The depth and the size of the flaw on the end face of the laminated belt ring can be detected. The laminated belt ring may be mounted on a cartridge so as to be able to move around, and a plurality of microscope cameras may be provided with their fields of view shifted in the width direction of the end face of the laminated belt ring.
[0009]
According to the above configuration, a clear image of the focused portion can be obtained by moving the microscope focal point. By integrating the focused images, a distance image can be obtained, and a three-dimensional image can be generated. If the end face of the laminated belt ring has a flaw, it can be grasped as a dent, and since it is a distance image, the size of the dent can be calculated. By rotating the visual field of the microscope along the belt ring, a distance image can be obtained over the entire circumference, and the number of scratches can be grasped. By moving the microscope camera in the thickness direction of the laminated belt ring, flaws can be inspected all around even if the field of view is narrow, but multiple microscope cameras should be arranged in the thickness direction of the belt ring so that the fields of view do not overlap each other. Thereby, a batch inspection can be performed in one round of the ring. By mounting the laminated belt ring on the cartridge and moving it around, a highly accurate inspection can be performed without changing the relative position with respect to the microscope camera.
[0010]
In such a configuration, a microscope camera capable of generating a distance image at high speed may be used, and a microscope camera having a structure in which a focal length is changed at high speed by moving an objective lens may be used. The camera was attached to a microscope, and a rotary stage for changing the position of the visual field in the circumferential direction of the laminated belt ring, a uniaxial stage capable of moving in the concentric direction of the laminated belt ring, and a cartridge capable of accurately installing the laminated belt ring were provided. What is necessary is just to construct a laminated belt ring inspection apparatus. Further, the laminated belt ring may be attached to a cartridge or the like so that the laminated belt ring is arranged at a specific position according to an inspection pattern.
[0011]
This enables a camera that can generate distance images at high speed, manages the depth of scratches, performs sufficient quality control, and improves handling efficiency by providing a cartridge that can accurately install the laminated belt ring. Thus, the installation accuracy can be improved.
[0012]
The laminated belt ring inspection includes a single ring inspection for inspecting one ring and an assembly ring inspection in which a plurality of metal ring sheets having different ring diameters are concentrically combined. In the single product ring inspection, a plurality of belt belt rings can be simultaneously inspected by arranging the belt belt ring at a specific position. Due to the arrangement effect of the laminated belt ring, the inspection of the laminated belt ring can be performed at high speed.
[0013]
With this configuration, all of the constituent units are mechanisms capable of automatic control, so that the inspection of the laminated belt ring can be automatically performed. Therefore, it is possible to eliminate individual differences and labor saving, which are problems of the conventional inspection by a person. As a result, in the laminated belt ring inspection device constructed using the above means, high-speed processing equivalent to the inspection time by a human can be performed.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, specific embodiments of a method for inspecting a laminated belt ring according to the present invention and an inspection apparatus therefor will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram of the entirety of the laminated belt ring inspection apparatus according to the embodiment. As shown in the figure, a cartridge 12 for holding a position of a laminated belt ring 10 to be inspected is attached to a rotary table 14. As the cartridge 12, a circular ring groove 16 having a thickness width of the laminated belt ring 10 is formed, and one side edge portion of the laminated belt ring 10 is fitted into the circular ring groove 16 and mounted. The position is held with the end face facing upward. Therefore, by determining the mounting position so that the center of rotation of the rotary table 14 and the center of the circular ring groove 16 of the cartridge 12 coincide with each other, if the table is rotated, the laminated belt ring 10 held by the cartridge 12 will be constant. Makes a circular motion following the circular locus. Thus, if the microscope camera 18 for inspection is arranged at a fixed position toward the end face of the belt ring, the end face can be photographed over the entire circumference of the belt ring 10.
[0015]
The microscope camera 18 is attached so that the photographing surface is directed to the end surface of the laminated belt ring 10 mounted on the cartridge 12 via the biaxial movement stage 20 as shown in the figure. The biaxial movement stage 20 is configured to move the microscope camera 18 in the thickness direction (ring radius direction) and the width direction (vertical direction) of the laminated belt ring 10. The positional relationship between the ring 10 and the constituent metal ring sheets and the distance from the end surface of the laminated belt ring 10 can be adjusted.
[0016]
The microscope camera 18 moves the focal length of the microscope having a shallow depth of field at high speed, acquires a plurality of images at different focal lengths, and synthesizes a plurality of in-focus images, thereby focusing on the entire field of view. And the depth data of the subject is obtained to obtain a three-dimensional stereoscopic image. Whether the object is in focus or not is determined by performing a local spatial frequency analysis around the observation point of the captured image while moving the focal length, the object distance, or the image distance, and the parameter where the spatial frequency is the maximum is in focus. Therefore, a plurality of image frames are captured while moving the objective lens by moving the objective lens using the variable focus mechanism, and a local spatial frequency analysis is performed around all the pixel points of the image frame. An omnifocal image can be obtained by picking up a portion where there is a pixel from each image and combining them as one image. The three-dimensional data can be obtained from the focal length and the image distance at each point.
[0017]
For this purpose, a distance image generator 22 for capturing image data from the microscope camera 18 is provided, and the distance image generator 22 transmits a three-dimensional image to a display 26 via a computer 24 so that an omnifocal image can be displayed. I have to. The distance image generator 22 captures an image of 1000 frames per second captured by the microscope camera 18 and performs the above-described processing on the omnifocal image in pixel units to display the combined image.
[0018]
The imaging data includes circumferential line data, which is calculated by the computer 24 to obtain height data along a predetermined line. This is the circumferential data of the ring for a predetermined line of the image field range. For example, a center line and left and right lines of the end face of each metal ring sheet 28 constituting the laminated belt ring 10 are determined, and only data along these lines is acquired. From the left end of the distance image, 1/4 is set to “left”, 2/4 is set to “center”, and 3/4 is set to “right”, and data in the circumferential direction at that position is extracted. From the line data, a normal product and a product with a flaw can be distinguished, and the width and depth of the flaw can be measured. FIG. 2 shows the relationship between the laminated belt ring 10 and the field of view of the microscope camera 18.
[0019]
In the embodiment, the laminated belt ring 10 is formed by stacking twelve metal ring sheets 28 each having a size of 9.2 mm × 0.186 mm (width × plate thickness), while the visual field 30 of the microscope camera 18 is 800 μm × 800 μm. is there. Therefore, with one microscope camera 18, only four metal ring sheets 28 can be included in the field of view 30. For this reason, the inspection is performed by moving the position by one rotation in one thickness direction of the laminated belt ring 10 by one microscope camera 18 so that the visual fields 30a, 30b, and 30c do not overlap with each other. Alternatively, three microscope cameras 18a, 18b, and 18c are used, and the visual fields 30a, 30b, and 30c are arranged so as not to overlap with each other in the thickness direction of the laminated belt ring 10 as shown in FIG. Inspection can be made by just using
[0020]
When a center line and a pair of left and right lines are set on the end face of each metal ring sheet 28, the result is as shown in FIG. 3A. In FIG. 3B, four metal ring sheets 28 are appropriately arranged in the field of view 30. FIG. 3C shows a case where the line set in the field of view is not properly arranged on the end face of the metal ring sheet 28. In the case of FIG. 6C, the microscope camera 18 may be adjusted to the position shown in FIG.
[0021]
FIGS. 4 and 5 show the results obtained by obtaining the distance image and the line data for each of the normal product and the damaged product.
[0022]
Since the inspection apparatus according to the embodiment has drive systems such as the rotary table 14 and the two-axis moving stage 20, control data for these drive system controllers 34 is input by the operating device 32 such as a keyboard, The drive system controller 34 is operated via the computer 24 which is supervised.
[0023]
FIG. 6 shows an overall control flowchart of the laminated belt ring inspection apparatus having such a configuration. When the inspection is started (step 100), first, the ring position is finely adjusted (step 102). This is a single-axis stage operation in the radial direction (thickness direction of the belt ring), and the single-axis stage is finely moved in the radial direction (thickness direction) so that the ring can be inspected with respect to the visual field 30 of the microscope camera 18. It is to let. This is done by adjusting the lines set in the visual field 30 so as to be properly positioned at the center position and the left and right positions of the end face of each metal ring sheet 28 as shown in FIG. This is for disposing the visual field 30 in the appropriate range shown in FIG. Thereafter, the rotary table 14 is rotated, moved at a distance corresponding to one visual field of the camera, and stopped (steps 104 and 106). After the rotation table stops, the microscope camera 18 outputs 1000 image frames per second while moving the objective lens up and down at a high speed (step 108), and enters a diagnostic processing operation (step 110). When acquiring an image frame, the microscope camera 18 outputs a distance image and a trigger signal at a cycle of 30 Hz. In practice, the inspection apparatus is controlled based on the trigger signal of the camera. As an example of this, FIG. 8 shows a timing chart of camera imaging, rotation of the rotary table 14, and analysis and diagnosis.
[0024]
FIG. 7 shows a specific flowchart of the diagnostic processing operation. The diagnostic work is started by acquiring data for one field of view of the camera (step 200), and first, line data is acquired from all focal length images as shown in FIGS. 4 and 5 (steps 202 and 204). Next, it is determined whether or not the width and depth of the circumferential line data are equal to or larger than a set value (step 206). This determines whether the difference between the maximum and minimum heights of the line data is greater than or equal to the set value, or if the data area length indicating data that is lower than the reference height in the circumferential direction is greater than or equal to the set value. The reference may be used, and the threshold can be set appropriately to enable automatic discrimination. As a result of this diagnosis, if it is determined that there is a flaw (step 208), the flaw position (position on the rotary table, one-axis stage position, ring number, etc.) is recorded in the memory (step 210), and the operation is completed. (Step 212). Of course, if it is determined that it is normal (step 214), the diagnostic work is terminated.
[0025]
When such a diagnosis operation is completed with the camera 1 visual field data, the flow returns to the original flow, and it is determined whether or not the image measurement of the four metal ring sheets 28 entering the visual field 30 of the microscope camera 18 has been normally completed. A determination is made (step 112). This is because the distance may not be output normally due to a shift in the height direction of the metal ring sheet 28 (a shift in the height of the 12 assembling rings, a shift in the accuracy of the rotary table 14, a shift in the ring installation, etc.). Therefore, the height of the microscope camera 18 is changed to collect distance images and check for ring flaws until a correct result is obtained for the target number. If abnormal termination has occurred, the microscope camera 18 is adjusted and moved in the height direction (step 114), and the process returns to step 108 again to acquire data. If the inspection is normally completed, the microscope camera 18 is reset and moved in the height direction to return to the initial position (step 116), and it is determined whether or not one round of inspection has been completed (step 118). Repeat until it goes around. The specified number of inspections, that is, whether or not all the twelve metal ring sheets 28 have been inspected are performed (step 120). If the inspection has not been completed, the uniaxial stage is not moved in the radial direction (thickness direction). (Step 122) The same data acquisition and inspection are repeated from Step 108. Finally, the determination result is output to and displayed on the display 26 (step 124), and the operation is terminated (step 126).
[0026]
As described above, according to the method and the apparatus for inspecting the laminated belt ring according to the present embodiment, it is possible to reliably detect even a minute flaw generated on the end surface of each metal ring sheet 28 of the laminated belt ring 10, and at the same time, Since the size of the flaw can also be automatically detected, the accuracy of the inspection with high uncertainty based on the conventional human work can be improved, and the inspection work efficiency can be greatly improved. In particular, since the field of view 30 of the microscope camera 18 is narrow, if the microscope cameras 18 are arranged in a plurality in the thickness direction of the laminated belt ring 10 so that the inspection can be performed collectively by one round of the ring, the work efficiency is further improved. Can be.
[0027]
【The invention's effect】
As described above, according to the present invention, there is provided a method for inspecting an end surface of a laminated belt ring, wherein the tertiary surface obtained by moving the focal point of a microscope and imaging the end surface of the belt ring while orbiting the belt ring. Since the configuration is such that the depth and the number of scratches on the end surface of the laminated belt ring are detected from the original image data, high-speed processing equivalent to the inspection time by a human can be performed. In addition, since the inspection of the laminated belt ring can be performed automatically, labor saving can be expected. Further, the machine-based inspection can eliminate the individual difference which has been a problem in the conventional human inspection. In addition, by performing measurement using a distance image, which is a three-dimensional image, the depth of the flaw can be managed, and sufficient quality control can be performed.
[Brief description of the drawings]
FIG. 1 is a configuration block diagram of an inspection device according to an embodiment.
FIG. 2 is a diagram illustrating a relationship between a laminated belt ring and a field of view of a microscope camera.
FIG. 3 is an explanatory diagram showing a relationship between a visual field of a microscope camera, an inspection line, and a metal ring sheet.
FIG. 4 shows a distance image and line data of a normal product.
FIG. 5 is a distance image and line data of a scratched product.
FIG. 6 is an overall processing flowchart of an inspection operation.
FIG. 7 is a flowchart of a diagnosis operation.
FIG. 8 is a timing chart of work.
[Explanation of symbols]
Reference numeral 10: laminated belt ring, 12: cartridge, 14: rotary table, 16: circular ring groove, 18: microscope camera, 20: biaxial moving stage, 22: distance Image generator, 24 Computer, 26 Display, 28 Metal ring sheet, 30 Microscope camera field of view, 32 Operating device, 34 Drive system controller.

Claims (5)

A method for inspecting the end face of a laminated belt ring, wherein the depth of the end face of the laminated belt ring is determined by three-dimensional image data obtained by moving the focal point of a microscope and imaging the end face of the belt ring while orbiting the belt ring. And a method for inspecting a laminated belt ring, wherein a size of a wound is detected. 2. The method according to claim 1, wherein a plurality of the microscopes are arranged so that different fields of view do not overlap in the thickness direction of the end surface of the laminated belt ring, and are inspected at once by moving the belt ring once. An apparatus for inspecting an end face of a laminated belt ring, comprising: a microscope camera capable of capturing an image of the end face of the belt ring and changing a focal length; and a driving unit capable of moving the microscope camera at least in a plane direction of the end face of the belt ring. Image processing means for generating a three-dimensional image from image data obtained by the microscope camera, and moving the focal point of the microscope while relatively rotating the laminated belt ring and the microscope camera to image the end face of the belt ring. And a display means for displaying the three-dimensional image data obtained by the method described above, wherein the depth and the size of the scratch on the end face of the stacked belt ring can be detected. 4. The apparatus according to claim 3, wherein the laminated belt ring is mounted on a cartridge and is capable of moving around. 4. The apparatus according to claim 3, wherein a plurality of the microscope cameras are provided so as to be shifted in a field of view in an end face width direction of the laminated belt ring.

Images