JP2005345261A - Workpiece inspection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a workpiece inspection device having high general-purpose properties, easily adapted to the inspection of a work even in a case that the shape or dimension of the workpiece is different or the upper and bottom surfaces of the workpiece are asymmetric and capable of performing the image processing of the workpiece continuously at a high speed. <P>SOLUTION: An upper feed belt 1 for horizontally feeding the workpiece W is provided and the lower feed belt 2 brought into contact with the reversal part of the upper feed belt 1 under pressure to reverse and hold the workpiece W on the upper feed belt 1 is provided. The workpiece W separated from the reversal part of the upper feed belt 1 is horizontally fed by the horizontal part of the lower feed belt 2. A plurality of cameras for subjecting the workpiece W to image processing are provided and an adjusting roller 3 for moving the position of the lower feed belt 2 corresponding to the height of the workpiece W on the upper feed belt 1 is mounted on the lower feed belt 2. The contact pressure to the workpiece W of the lower feed belt 2 is adjusted constant. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a workpiece inspection apparatus that uses two flat belts and can very flexibly cope with changes in the shape and size of a workpiece to be subjected to image processing inspection.

  Conventionally, an apparatus described in Patent Document 1 has been proposed as this type of workpiece inspection apparatus. According to this apparatus, in order to speed up the inspection of the work, a groove is formed in the conveying belt, the work is placed and conveyed in this groove, and the exposed surface of the work is imaged and inspected. It is. In this apparatus, in order to fix the work to be conveyed, a substantially V-shaped groove is also formed on the reversing belt that partially contacts the conveying belt in addition to the conveying belt.

On the other hand, Patent Document 2 discloses an inspection device that reverses a workpiece being conveyed while sucking it in order to reverse the workpiece to be conveyed. According to this device, the work is adsorbed to the upper surface of the endless belt arranged substantially horizontally and conveyed downstream in a line, and the energizing force of the endless belt is released near the lower end of the reversing operation part. Thus, the workpiece detached from the endless belt is received and conveyed in a state where the workpiece is turned upside down on the upper surface of the second endless belt which is positioned below and moved in the direction opposite to the first endless belt. Device.
JP 2001-327929 A Japanese Patent Laid-Open No. 9-288061

  The workpiece inspection apparatuses described in Patent Literature 1 and Patent Literature 2 are both devices that inspect and inspect four surfaces on the top, bottom, left, and right of a workpiece to be inspected by inverting the workpiece.

  However, according to Patent Document 1, since the workpiece is housed and transported in a substantially V-shaped groove formed on the belt, there is a problem that the shape of the workpiece to be inspected is limited to the one that conforms to the groove shape. That is, when the shape of the workpiece is smaller than this groove shape, for example, in the case of a bolt shape in which the workpiece falls into the groove, the workpiece cannot be pressed at the portion where the conveyance belt and the reverse belt abut. There is a risk of moving along. For this reason, the position of the workpiece is distorted, and it is difficult to accurately image the four surfaces of the workpiece.

  On the other hand, if the thickness of the workpiece is increased and the workpiece is greatly protruded from the substantially V-shaped groove formed on the belt, the force that holds the workpiece at the portion where the conveyance belt and the reverse belt abut becomes stronger, which adversely affects the workpiece. May occur. As described above, the workpiece inspection apparatus disclosed in Patent Document 1 cannot perform an accurate inspection when the size of the workpiece, such as the height or thickness, changes, and the force of pressing the workpiece increases to adversely affect the workpiece itself. There were still challenges.

  Furthermore, in the workpiece inspection apparatus of Patent Document 1, since the workpiece is housed and conveyed in a substantially V-shaped groove, when the upper surface and the bottom surface of the workpiece are asymmetrical, the substantially V-shaped groove in the conveying belt and the reversing belt It is necessary to match the substantially V-shaped grooves with the shapes of the upper surface and the bottom surface of the asymmetric workpiece. In addition, when the workpiece is placed on the conveyor belt from the parts feeder, it is necessary to select the upper surface and the bottom surface of the workpiece and align the surfaces that match the grooves of the conveyor belt. Therefore, not only arranging a large number of workpieces that are conveyed in a line, but also selecting the front and back surfaces of the workpieces, arranging them in a direction that matches the substantially V-shaped groove formed on the conveyor belt, and then feeding them onto the conveyor belt become. Thus, if it is going to respond | correspond to a various workpiece | work with the workpiece | work inspection apparatus of patent document 1, it is necessary to change the groove shape of a conveyance belt or a reversal belt for every kind of workpiece | work. Moreover, in order to perform image processing on workpieces with asymmetrical top and bottom surfaces, there are many problems such as the need for a setup that aligns the transfer direction of the workpiece and a high-performance parts feeder that automatically aligns the transfer direction. It is.

  On the other hand, in the workpiece inspection apparatus described in Patent Literature 2, the workpiece is conveyed while being attracted, and the biasing force is released in the vicinity of the lower end of the reversing operation portion of the endless belt. As shown in FIG. 1, even if the height or thickness of the workpiece is increased, there is no possibility of adversely affecting the workpiece itself. However, in Patent Literature 2, a suction device is attached to the first endless belt, and a suction device that attracts the workpiece is also attached to the second endless belt. For this reason, each of these two endless belts requires a suction device and various equipment necessary for the suction means, and the work inspection device must be an extremely complicated device.

  Moreover, in Patent Document 2, it is necessary to adjust so that the distance between these two belts is substantially equal to the thickness of the workpiece. That is, when the work is turned over and the suction force is released and the work is received on the upper surface of the second endless belt, if the distance between the belts is larger than the thickness of the work, This is because there is a risk that the workpiece will bounce and position displacement occurs. Therefore, a separate device is always required to adjust the distance between the two belts according to the size of the workpiece. As described above, in Patent Document 2, an extremely complicated transfer device is required as a workpiece inspection device.

  Therefore, the present invention was created to solve the above-described problems, and it is a workpiece inspection device having a relatively simple configuration, but when the shape and dimensions of the workpiece are different, or the upper surface and the bottom surface of the workpiece are asymmetrical. The purpose of the present invention is to provide a work inspection apparatus that has a high versatility such as adapting extremely flexibly even in some cases, and that can take an image with extremely accurate timing even after reverse transfer without adversely affecting the work. .

  The first means of the present invention includes an upper conveyor belt 1 that horizontally conveys the workpiece W and a work piece on the upper conveyor belt 1 that is pressed against the reversing portion of the upper conveyance belt 1 to hold it in reverse. Work inspection apparatus comprising: a lower conveyance belt 2 that horizontally conveys a workpiece W separated from the upper conveyance belt 1 at a horizontal portion located below the upper conveyance belt 1; and a plurality of cameras that perform image processing on the workpiece W being conveyed. 2, an adjustment roller 3 that moves the position of the lower conveyor belt 2 according to the height of the workpiece W placed on the upper conveyor belt 1 is attached to the lower conveyor belt 2, and the contact pressure of the lower conveyor belt 2 to the workpiece W is constant. It is in providing to adjust to.

  The second means arranges an upper imaging camera C1 that images the workpiece W placed on the upper conveyor belt 1 and a lower imaging camera C2 that images the workpiece W reversed by the lower conveyor belt 2. The upper surface and the bottom surface of the workpiece W are individually determined based on the respective imaging information of the upper imaging camera C1 and the lower imaging camera C2, and the acceptance / rejection of the workpiece W is determined.

  The third means includes an angle detector 4 that detects the amount of movement of the lower conveyor belt 2 in the lower conveyor belt 2, and a position that detects the passage of the horizontally moving workpiece W at a downstream position of the lower conveyor belt 2. The sensor 5 is mounted, and the amount of movement of the work W after passing through the position sensor 5 is detected by the angle detector 4 so that the work W is picked up and sorted.

  The position sensor 5 in the fourth means is disposed at a position distant from the image picked up by the camera, and detects the center position of the workpiece W passing based on the passage information between the leading end portion and the trailing end portion of the workpiece W. It is provided to do.

  The fifth means uses a rotary encoder attached to a roller portion at the downstream end of the lower conveying belt 2 as the angle detector 4 to solve the problem.

  According to the first aspect of the present invention, the belt adjusting roller 3 for moving the position of the lower transport belt 2 according to the height of the work W placed on the upper transport belt 1 is mounted, and the contact pressure of the lower transport belt 2 to the work W is attached. Therefore, even if the size such as the height and thickness of the workpiece W increases, the contact pressure with respect to the workpiece W does not change. Therefore, it can be reversed without adversely affecting the workpiece W.

  In addition, since the workpiece W is reversed between the upper conveyor belt 1 and the lower conveyor belt 2 via the belt adjustment roller 3, the upper conveyor belt 1 and the lower conveyor belt can be used even when the shape and size of the workpiece W are different. Since it is not necessary to change 2 and imaging can be performed as it is, the workpiece inspection apparatus has a relatively simple configuration and has extremely high versatility.

  According to claim 2, since the upper surface and the bottom surface of the workpiece W are discriminated from each other by the imaging information of the upper imaging camera C1 and the lower imaging camera C2, the pass / fail of the workpiece W is determined. A large number of workpieces W can be imaged at high speed and continuously, and pass / fail workpieces W can be sorted. Therefore, even if the upper surface and the bottom surface of the workpiece W are non-target shapes, it is not necessary to align the conveyance direction of the workpiece W. As a result, it is possible to take an image with a very simple configuration without requiring a setup for aligning the conveyance direction of the workpiece W and a high-performance parts feeder that automatically aligns the conveyance direction. As described above, the supply speed of the workpiece W can be increased, the processing capability can be increased, and the upper surface and the bottom surface of the workpiece W can be imaged at high speed and continuously.

  According to a third aspect of the present invention, at the downstream position of the lower conveyance belt 2, the movement amount of the workpiece W after passing through the position sensor 5 is detected by the angle detector 4 so that the workpiece W is imaged. By detecting the delayed advance of the lower conveyor belt 2 caused by the position adjustment of the lower conveyor belt 2, it is possible to take accurate imaging and separation timing.

  Since the position sensor 5 according to the fourth aspect is disposed at a position away from the image of the camera, the position sensor 5 can be prevented from being reflected when the workpiece W is imaged. In addition, since the center position of the workpiece W that passes is detected based on the passage information between the front end portion and the rear end portion of the workpiece W, the imaging point can be set in accordance with the center of the workpiece W. it can. As a result, even if the size of the workpiece W changes, there is no need to change the imaging point, and the effect of further improving the general-purpose performance is achieved.

  As described in claim 5, by using a rotary encoder mounted on the roller portion at the downstream end of the lower conveyor belt 2 as the angle detector 4, the amount of movement of the lower conveyor belt 2 is measured and analyzed by a personal computer. be able to. Therefore, it is possible to measure the movement amount very accurately.

  As described above, according to the present invention, although the workpiece inspection apparatus has a relatively simple configuration, the workpiece can be transported at high speed and continuously, and when the shape and dimensions of the workpiece are different, or the upper surface and the bottom surface of the workpiece are asymmetrical. In addition, the belt adapts easily even if the workpiece thickness is different and does not adversely affect the workpiece. It is possible to achieve various beneficial effects such as being able to do so.

  The best mode of the present invention includes an upper imaging camera C1 that images the workpiece W placed on the upper conveyor belt 1, and a lower imaging camera C2 that images the workpiece W inverted by the lower conveyor belt 2. . The upper and lower surfaces of the workpiece W are discriminated from the imaging information of the upper imaging camera C1 and the lower imaging camera C2, and whether the workpiece W is accepted or not is determined. A belt adjustment roller 3 for moving the position of the lower conveyor belt 2 according to the height of the workpiece W placed on the upper conveyor belt 1 is mounted so as to adjust the contact pressure of the lower conveyor belt 2 to the workpiece W to be constant. . The lower conveyor belt 2 is provided with an angle detector 4 using a rotary encoder that detects the amount of movement of the lower conveyor belt 2. A position sensor 5 for detecting the passage of the horizontally moving workpiece W is mounted at a downstream position of the lower conveyor belt 2. The movement of the workpiece W after passing through the position sensor 5 is detected by the angle detector 4, and the workpiece W is imaged and sorted to achieve the original purpose.

  The basic configuration of the workpiece inspection apparatus of the present invention includes a plurality of cameras, an upper conveyance belt 1, a lower conveyance belt 2, a belt adjustment roller 3, an angle detector 4, a position sensor 5, and the like.

  The upper conveyance belt 1 is an endless belt that horizontally conveys the workpiece W, and the workpieces W aligned and conveyed from the parts feeder 6 are supplied to the upper conveyance belt 1 one by one. The upper conveyor belt 1 conveys the workpiece W by the rotation of the driving roller 7. Then, the upper imaging camera C1 images the upper surface of the work W placed on the upper conveyance belt 1. Further, a position sensor 10 for detecting the passage of the horizontally moving workpiece W is mounted at an upstream position of the upper conveyor belt 1 so as to image the workpiece W after passing through the position sensor 10. At this time, an angle detector (not shown) is mounted on the driving roller 7 together with the position sensor 10, and the passage is made based on the passing information between the front end portion and the rear end portion of the work W sensed by the position sensor 10. The center position of the workpiece W to be detected is provided. In addition, the position sensor 10 is disposed at a position away from the image pick-up of the camera to prevent the position sensor 10 from being reflected during image pickup.

  The lower conveyor belt 2 is an endless belt that contacts the inverted portion of the upper conveyor belt 1 with a predetermined pressure. After the workpiece W on the upper conveyor belt 1 is inverted at this contact portion, the inverted workpiece W is conveyed to the lower portion. The belt 2 is transported in the opposite direction of the upper transport belt 1 at the horizontal portion. When the lower conveyor belt 2 is reversed while holding the workpiece W at the inverted portion of the upper conveyor belt 1, the belt adjusting roller 3 is arranged so that the lower conveyor belt 2 always contacts the workpiece W with a substantially constant pressure. It is adjusted.

  This belt adjustment roller 3 adjusts the contact pressure to the work W to be constant by moving the position of the lower transport belt 2 by changing the size of the work W placed on the upper transport belt 1 such as the height and thickness. doing. In the illustrated example, the contact position of the lower conveyor belt 2 with respect to the upper conveyor belt 1 is provided so as to be movable to the left and right. When the lower conveyor belt 2 comes into contact with the workpiece W having an increased height and thickness, the resistance applied to the lower conveyor belt 2 increases, and the position of the belt adjustment roller 3 moves with the increased resistance. The contact pressure is adjusted.

  In order to perform image processing on the workpiece W on the upper conveyance belt 1 and the workpiece W on the lower conveyance belt 2 conveyed in the opposite direction to the upper conveyance belt 1, a plurality of cameras are provided. The illustrated camera includes an upper imaging camera C1 that images the upper surface of the workpiece W placed on the upper conveyor belt 1, and a lower imaging camera C2 that images the inverted workpiece W on the lower conveyor belt 2. . Although not shown, it is also possible to attach a camera that images both the left and right sides of the workpiece W. Thus, in the present invention, it is possible to image the workpiece W from the top, bottom, left and right.

  According to each imaging information imaged by these camera groups, inspection items that can be processed by image processing such as scratches on the surface of the workpiece W are executed in addition to the size and shape of the workpiece W by processing of a personal computer (not shown). The determined workpiece W is separated and removed from the transfer device. The illustrated camera includes an upper imaging camera C1 that images the workpiece W placed on the upper conveyance belt 1 and a lower imaging camera C2 that images the workpiece W inverted by the lower conveyance belt 2. Then, the upper and lower surfaces of the workpiece W are discriminated from the imaging information of the upper imaging camera C1, and whether the workpiece is acceptable or not is determined. Also, the imaging information of the lower imaging camera C2 is provided so as to determine the top and bottom surfaces of the workpiece W and whether the workpiece W is acceptable or not. In this way, when the determination is individually made based on the information of each imaging camera, when inspecting a workpiece W having an asymmetric top surface and bottom surface, either surface may be imaged first.

  A removal device 9 is mounted immediately before the chute 8 downstream from the installation position of the lower imaging camera C2. The removal device 9 separates and removes rejected products of the workpiece W, and only the accepted products are conveyed to the chute 8. The workpiece W removal device 9 can be selected from any means such as a pneumatic device or a mechanical press.

  When the belt adjusting roller 3 is moved according to the height of the workpiece W, the lower conveyor belt 2 returns to the original position at the moment when the workpiece W is separated from the rotating portion of the upper conveyor belt 1. At this time, the belt adjustment roller 3 is returned to the original position by the urging force of the belt adjusting roller 3, but due to the action of this urging force, the conveying distance of the lower conveying belt 2 is extended for a moment, and the inverted work W on the lower conveying belt 2. There is a risk that the timing of capturing the image will be out of order.

  Therefore, the lower conveyor belt 2 is provided with an angle detector 4 that detects the amount of movement of the lower conveyor belt 2. The illustrated angle detector 4 measures and analyzes the conveyance distance of the lower conveyance belt 2 with a personal computer using a rotary encoder attached to the roller 2A portion located at the downstream end of the lower conveyance belt 2. Further, a position sensor 5 for detecting the passage of the horizontally moving workpiece W is mounted at a downstream position of the lower conveying belt 2, and the amount of movement of the workpiece W after passing through the position sensor 5 is detected by this angle detector 4. Thus, the work W is provided to be imaged. At this time, the position sensor 5 is disposed at a position distant from the image picked up by the camera to prevent the position sensor 5 from being reflected during image pick-up. Further, the center position of the passing workpiece W is detected based on the passing information of the leading end portion and the trailing end portion of the workpiece W sensed by the position sensor 5. By detecting the amount of movement of the workpiece W from the center position with the angle detector 4 and using it as the imaging point of the lower imaging camera C2, the center position of the workpiece W is always determined even if the size and shape of the workpiece W are different. It becomes possible to take an image with reference.

  Since the angle detector 4 always detects the moving distance from the position sensor 5 to the lower imaging camera C2, as described above, even when the lower conveying belt 2 is moved by the action of the belt adjusting roller 3, The workpiece W can be imaged with extremely accurate timing.

  In addition, each structure of the example of illustration in this invention is only one Example of this invention, and is within the technical range currently known, such as the design change of the number of cameras, the form of a lower conveyance belt 2, etc., a dimension, etc. It can be changed freely.

It is a perspective view which shows one Example of the workpiece | work inspection apparatus in this invention. It is a schematic side view of the workpiece inspection apparatus in the present invention.

Explanation of symbols

W Work C1 Upper imaging camera C2 Lower imaging camera 1 Upper conveyor belt 2 Lower conveyor belt 3 Belt adjustment roller 4 Angle detector 5 Position sensor 6 Parts feeder 7 Driving roller 8 Chute 9 Removal device

Claims (5)

  The upper conveyor belt that transports the workpiece horizontally and the work on the upper conveyor belt are reversed and held by pressing against the reversing part of the upper conveyor belt, and the work that has left the reversing part is positioned below the upper conveyor belt. In a workpiece inspection apparatus including a lower conveyance belt that horizontally conveys at a horizontal portion and a plurality of cameras that perform image processing on the workpiece being conveyed, the lower conveyance belt may have a height depending on the height of the workpiece placed on the upper conveyance belt. An apparatus for inspecting a workpiece, wherein an adjustment roller for moving the position is attached to the lower conveyor belt so as to adjust the contact pressure of the lower conveyor belt to the workpiece to be constant.   An upper imaging camera for imaging a workpiece placed on the upper conveyor belt and a lower imaging camera for imaging a workpiece inverted by the lower conveyor belt are arranged, and the upper imaging camera and the lower imaging camera are arranged The workpiece inspection apparatus according to claim 1, wherein the workpiece inspection apparatus is configured to individually determine the upper surface and the bottom surface of the workpiece based on the respective imaging information, and to determine whether the workpiece is acceptable or not.   The lower conveyor belt is provided with an angle detector that detects the amount of movement of the lower conveyor belt, and a position sensor that detects the passage of a horizontally moving workpiece is attached to a downstream position of the lower conveyor belt, and the position sensor passes. The workpiece inspection apparatus according to claim 1 or 2, wherein a movement amount of a subsequent workpiece is detected by the angle detector, and the workpiece is imaged and sorted.   The position sensor is disposed at a position distant from an image pick-up of a camera, and is provided so as to detect a center position of a workpiece passing based on passage information between a tip end portion and a rear end portion of the workpiece. 3. Work inspection apparatus according to 3. The work inspection apparatus according to claim 2, wherein a rotary encoder attached to a roller at a downstream end of the lower conveying belt is used as the angle detector.

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