JP4852516B2 - Substrate inspection method and substrate inspection apparatus - Google Patents

Description

  The present invention relates to a method for inspecting a mounting state of a component on a substrate including a printed state of solder using a plurality of cameras.

  An appearance inspection machine is a device that inspects the printed state of solder, the mounting position and mounting state of a component by imaging the component mounted on the substrate by the component mounting machine and processing the obtained image. is there.

  FIG. 10A is a plan view of a conventional one-head inspection machine. The inspection machine 900 has a head 1 with a camera attached to the lower part. The head 1 is configured to be movable in the X and Y directions. The board 20 on which the component is mounted is conveyed by a conveyor rail 902 to a position where the camera can take an image, and is temporarily stopped until the inspection is completed. Since the field of view of the camera is limited, the head 1 moves on the substrate 20 while the substrate is stopped, and the state of the components mounted on the substrate 20 is imaged by the camera attached to the head 1. .

FIG. 10B is a diagram illustrating an example of an imaging sequence when a conventional inspection machine inspects components on a board. As shown in FIG. 10B, in the conventional visual inspection, in order to more efficiently image and inspect the mounting state of components on the substrate 20, the inspection area on the substrate 20 is divided into the size of the field of view of the camera. The image is divided into (ID1 to ID6), and the field of view of the camera is moved in the X direction along the section (ID1 → ID2 → ID3). At this time, the section where no part exists is skipped, and the position of the field of view is reset so that the section where the part exists includes the maximum number of parts in the field of view. The order of movement of the field of view set in this way is a one-section movement in the Y direction at the dead end moved in the X direction (ID3 → ID4), and then moved in the reverse direction in the X direction (ID4 → ID5 → ID6). (For example, refer to Patent Document 1).
JP-A-3-210411

  However, in such an appearance inspection, it is necessary to accurately image components, but there are an increasing number of components with small sizes and components with small intervals between leads (electrodes), and such components have high resolution. Imaging is required. However, the position of the field of view of the section where the part is present is set so that the maximum number of parts are included in the field of view, and the image data of the substrate 20 imaged at a high resolution is moved by moving the camera to the field of view. When the imaging, image processing, and inspection are repeated every time, the image processing capability of the CPU is not catching up. As a result, the memory stock of the image data becomes full, and the imaging must be stopped until the image processing is completed, which causes a problem of tact loss. Note that the memory stock refers to unprocessed image data stored in the image memory.

  FIG. 11A is a diagram showing an example of the relationship between each tact and the amount of memory stock of image data when the sections on the substrate are imaged in the order shown in FIG. FIG. 11B is an example of a timing chart of the inspection machine when the sections on the substrate are imaged in the order shown in FIG. For example, the time required for the camera to store the image data obtained by imaging the section ID1 in the image memory is 5 seconds, and the memory stock at this time is 50%. Next, the time required to image the section of ID2 is 3 seconds, and the memory stock becomes 80% at this point. Further, it takes 3 seconds to continuously capture the ID3 section, and the memory stock is 100%. When the memory stock reaches 100%, the image data cannot be stored even if more images are taken, so the head 1 waits for image processing by the CPU until the memory stock runs out. This waiting time of 3 seconds is the tact loss of the inspection machine. After this waiting time, the memory stock becomes 0%. Therefore, when the sections of ID4 and ID5 are imaged, the image processing of the CPU is not in time, so the memory stock becomes 100% again. Here, a waiting time of 3 seconds for waiting for image processing of the CPU again occurs, and after 3 seconds, the memory stock becomes 0%, but this 3 seconds becomes the tact loss of the inspection machine. Finally, it takes 5 seconds to image the section ID6. As a result, the inspection machine requires 30 seconds to complete the inspection of the substrate divided into the sections ID1 to ID6.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to reduce tact loss caused by the upper limit of the image processing capability of a CPU in an appearance inspection machine that captures images of parts with a camera.

In order to achieve the above object, a method for inspecting a substrate according to an aspect of the present invention includes imaging a substrate with an inspection head equipped with a camera, and analyzing the captured image to detect whether a component is mounted or soldered. A substrate inspection method for inspecting a surface state of a substrate including a printed state of a plurality of inspection heads each having one camera for imaging a substrate, wherein predetermined regions are alternately arranged on the substrate. The image processing is performed in parallel, the image processing and the image processing of the captured image are performed in parallel, and the image data generated by imaging the region is accumulated for each inspection head, and is accumulated for the inspection head being imaged. In accordance with the amount of the image data that has been determined, it is determined whether or not the inspection head needs to interrupt imaging. And replacement, and performs image processing of storing said image data.
In addition, the substrate inspection method according to another aspect of the present invention includes the component mounting state and the solder printing state by imaging the substrate with an inspection head equipped with a camera and analyzing the captured image. A substrate inspection method for inspecting a surface state of a substrate, wherein the inspection is performed by alternately imaging the substrate with a plurality of inspection heads.

  As a result, when the memory stock of one head exceeds the threshold value, it is possible to take an image of the substrate by switching to another head, so that another head can be used while performing image processing of the memory stock by the one head. The substrate can be imaged in parallel, and tact loss can be minimized.

  The present invention can be realized not only as a substrate inspection method including the characteristic steps as described above, but also as a substrate inspection apparatus including a processing unit that executes the steps included in the substrate inspection method. it can. Moreover, not only can it be realized as a head switching determination method including the characteristic steps as described above, but it can also be realized as a program that causes a computer to execute the characteristic steps included in the head switching determination method. . Needless to say, such a program can be distributed via a recording medium such as a CD-ROM (Compact Disc-Read Only Memory) or a communication network such as the Internet.

  As described above, according to the present invention, when imaging by one inspection head enters a waiting state, the imaging is replaced with another inspection head, and image data that has been captured during the substrate imaging operation by the other head. Since image processing can be continued, there is an effect that tact loss in substrate inspection can be minimized.

Hereinafter, an inspection machine according to an embodiment of the present invention will be described.
FIG. 1 is an external view showing a configuration of a component mounting system including an inspection machine 100 according to an embodiment of the present invention. FIG. 1A is a diagram illustrating an appearance of a component mounting system including an inspection machine 100 according to the present embodiment. FIG. 1B is a plan view of the component mounting system shown in FIG.

  As shown in FIG. 1A, the component mounting system according to the present embodiment includes a plurality of mounting machines and one inspection machine 100. The plurality of mounting machines pick up the components from the component cassette by the mounting head while feeding the substrate 20 from the upstream (left hand side as viewed in FIG. 1) to the downstream (right hand side as viewed in FIG. 1). Mount electronic components. Then, the surface state of the board | substrate 20 is test | inspected with the inspection machine 100 located in the most downstream. Each mounting machine includes two mounting heads that perform an alternating operation in cooperation with each other. Similarly, the inspection machine 100 is also provided with two inspection heads that perform mutual operations with emphasis on each other.

  FIG. 2 is a plan view of the inspection machine 100 and a method for inspecting the surface state of the substrate. The left view of FIG. 2 is a plan view of the inspection machine 100. The right diagram in FIG. 2 is a diagram showing a partition as a unit of recognition on the substrate 20. Small squares on the substrate 20 indicate mounted electronic components.

  First, the inspection machine 100 includes a head 1 and a head 2 which are two inspection heads. The substrate 20 on which the component mounting is completed is conveyed from the upstream mounting machine in the X direction by the conveyor rail 902 to the central portion of the inspection machine 100. The head 1 is attached to a beam 903 attached so that the longitudinal direction is in the X direction, and the head 2 is attached to a beam 904 attached so that the longitudinal direction is also in the X direction. The beams 903 and 904 can be individually slid in the Y direction, and the head can be individually slid in the X direction along the beam to which each beam is mounted. Thereby, the head 1 and the head 2 can be moved to arbitrary positions on the substrate 20. The plan view of the inspection machine 100 shows that the head 1 enters the substrate 20 and the camera 104 inspects the surface state of the substrate 20. The camera 104 of the head 1 and the head 2 performs, for example, an outline inspection on the substrate 20 with a large field of view (for example, a hatched portion on the substrate 20) as shown in the right figure. When a likely part or missing part is found, a detailed inspection with a small visual field (for example, a white part in a hatched part on the substrate 20) can be performed.

  FIG. 3 shows an example in which the inspection machine 100 performs imaging by switching to the head 2 after imaging by the head 1. FIG. 3A is a diagram illustrating a state in which the head 2 is retracted from the substrate 20 while the head 1 is imaging the substrate 20. FIG. 3B is a diagram illustrating a state in which the head 2 replaces the head 1 and images the substrate 20 after the head 1 has been retracted from the substrate 20. As shown in FIG. 3A, for example, while the head 1 is imaging on the substrate 20, the other head 2 is retracted from the substrate 20 and is stationary. Next, when the amount of image data that has not been processed by the image data captured by the head 1 exceeds a certain amount and the head 1 cannot continue the image capturing process, the beam 903 slides in the negative Y direction. The head 1 is retracted from the substrate 20. In accordance with this, the beam 904 slides in the negative direction of the Y direction, and the head 2 is moved to a position on the substrate 20. As a result, as shown in FIG. 3B, the head 1 retracts from the substrate 20 and stops, and the head 2 moves in the recognition area on the substrate 20 and performs imaging.

FIG. 4 is a block diagram illustrating a configuration of the inspection machine 100.
The inspection machine 100 images a substrate with an inspection head equipped with a camera, and analyzes the captured image to inspect a substrate surface state including a component mounting state and a solder printing state. And it is an example of the board | substrate test | inspection apparatus provided with the said some test | inspection head and image | photographing a board | substrate alternately with the said some test | inspection head, and performing the said test | inspection. The inspection machine 100 includes a display unit 102, an input unit 103, a mechanism unit 120, a mechanism control unit 111, a storage unit 114, a communication I / F unit 115, and a camera switching timing determination unit 116. The mechanism control unit 111 and the camera switching timing determination unit 116 are realized by a CPU (Central Processing Unit) 150.

  The input unit 103 is an interface for inputting or changing mounting data described later, switching timing of the camera 104, and the like, such as a keyboard, a touch panel, and a mouse. The above-described mounting data is data indicating what part is mounted on which part on the substrate 20.

  The storage unit 114 is a storage medium that stores mounting data 114 a including information related to components mounted on the board 20, an imaging region of the camera 104, and the like. The above-described imaging area refers to an area on the substrate divided into predetermined sections. The storage unit 114 further includes, for each head, an image memory that is a storage area for storing image data generated by imaging by the camera 104.

  The mechanism unit 120 includes the head 1 and the head 2, and the beam 903 and the beam 904 that move the head 1 and the head 2 in the Y direction, and the head 1 and the head 2 in the X direction along the beam 903 and the beam 904, respectively. It has a motor to drive. Each of the two inspection heads includes one camera 104.

  The display unit 102 displays the result of the head 1 and the head 2 of the inspection machine 100 inspecting the surface state of the substrate 20.

  The camera 104 images the surface state of the substrate for each section divided into a predetermined size. In order to reduce the weight of the head, one camera 104 is provided in one head, and the number of pixels captured by one camera 104 is increased. This allows only one of head 1 or head 2 to perform an overview inspection in a large field of view and a detailed inspection in a small field of view without having multiple cameras with different fields of view and a zoom function in one inspection head. can do. For example, using such a camera 104, the mechanism control unit 111 performs a general inspection in a large field of view at a low resolution by pixel thinning or the like, and performs a detailed inspection at an original resolution particularly for a portion requiring a detailed inspection. Do.

  The mechanism control unit 111 is a processing unit that controls the inspection machine 100, and is, for example, a CPU. The mechanism control unit 111 refers to the information stored in the storage unit 114, controls the mechanism unit 120, and causes the head 1 and the head 2 to inspect the surface state of the substrate 20 after component mounting. The mechanism control unit 111 executes applications of the respective heads in parallel, such as imaging processing and image processing of the head 1 and the head 2, by time sharing or the like. The mechanism control unit 111 performs image processing on image data captured by the camera 104. Further, the mechanism control unit 111 performs image processing on the image data stored in the image memory and performs component mounting defects (mounting component errors, mounting position shifts, solder shifts, blurring, blurring, component mounting leaks, etc.) ) Is determined. When the mechanism control unit 111 finishes the image processing of the image data stored in the image memory, the mechanism control unit 111 deletes or overwrites the image processed image data. When the mechanism control unit 111 determines that there is a problem in mounting the component on the board 20 or that there is a specific component for which detailed inspection is specified in advance, the mechanism control unit 111 backs up the image of the corresponding part and later displays the display unit. The operator is notified by displaying it on 102 or the like.

  The communication I / F (interface) unit 115 is an interface for communicating with other machines constituting the mounting board production system, a host computer (not shown), and the like, for example, with a LAN (Local Area Network) adapter or the like. is there.

  When the unprocessed image data that has not been subjected to image processing by the mechanism control unit 111 is accumulated in the image memory assigned to the head being imaged, the camera switching timing determination unit 116 sets the head to the substrate. The mechanism controller 111 is determined to retreat from the top and to continue the image processing of the image data corresponding to the retreated head. At the same time, in place of the retracted head, the other head enters the substrate 20 to start imaging. The camera switching timing determination unit 116 determines whether or not unprocessed image data is accumulated in a certain amount or more in the image memory of the head being imaged for each section on the substrate 20 and performs the above determination.

  FIG. 5A is a diagram showing an alternating operation of the head 1 and the head 2 in the inspection machine 100. FIG. 5B is a diagram illustrating an example of a partition serving as a unit of imaging of the camera 104 when the alternate inspection is performed between the head 1 and the head 2. FIG. 6 is a diagram showing a procedure for efficiently recognizing the section of the substrate 20 shown in FIG. 5B by the alternate inspection of the head 1 and the head 2. FIG. 6A is a table showing the relationship between the replacement timing of the heads 1 and 2 and the amount of memory stock in the image memory when the sections shown in FIG. 5B are sequentially imaged. FIG. 6B is a timing chart showing the replacement timing of the head 1 and the head 2 when sequentially imaging the sections shown in FIG.

  As shown in FIG. 5A, for example, when the head 1 enters the substrate 20 to inspect the surface state, it is necessary to perform image processing on the image data obtained by the imaging of the camera 104 of the head 1. . Therefore, the image processing is executed by the mechanism control unit 111 after the image pickup by the camera 104 is executed and subsequently. The mechanism control unit 111 executes image processing of the retracted head subsequent to imaging, and in parallel with this, controls other cameras to sequentially execute imaging of the next section. For this reason, the image data sequentially stored in the image memory needs to be stored in the image memory for each head until the image processing by the mechanism control unit 111 is completed. However, since the storage capacity of the image memory is limited, when the storage amount of the image data is close to the limit, it is impossible to capture more image data. That is, it becomes impossible to capture an image until all the image processing of the accumulated image data is completed. Therefore, the camera switching timing determination unit 116 retracts the head 1 from the substrate 20 and causes the mechanism control unit 111 to continue image processing of the image data of the head 1. At the same time, the mechanism control unit 111 controls the head 2 to enter the substrate 20 and starts imaging the surface state of the substrate 20.

  For example, as shown in FIG. 5 (b), the substrate 20 is preliminarily defined with a section as a unit for inspection. That is, sections from ID1 to ID6 are defined. Here, the order in which the two heads 1 and 2 recognize each section is the same as the order described with reference to FIG. That is, the inspection area on the substrate 20 is divided into sections (ID1 to ID6) having the size of the field of view of the camera, and the field of view of the camera is moved along the section in the X direction (ID1 → ID2 → ID3). . At this time, the section where no part exists is skipped, and the position of the field of view is reset so that the section where the part exists includes the maximum number of parts in the field of view. The order of movement of the field of view set in this way is a one-section movement in the Y direction at the dead end moved in the X direction (ID3 → ID4), and then moved in the reverse direction in the X direction (ID4 → ID5 → ID6). Move with.

  In this manner, the head 1 first picks up images of each section in ascending order of the numbers assigned to the IDs from the section of ID1. As shown in FIG. 6A, the time required for the camera 104 of the head 1 to image the section ID1 is 5 seconds, and the memory stock at this time has a capacity of 50% of the image memory (head 1 (1)). Next, the time required to image the section of ID2 is 3 seconds, and the memory stock becomes 80% (operation (2) of head 1). Further, it takes 3 seconds to continuously take an image of the section of ID3. As a result, the memory stock stored in the image memory becomes 100% (operation (3) of the head 1). For this reason, the head 1 can no longer continue imaging, and enters a waiting state (operation (4) of the head 1). At this time, the time required for the CPU to process all the memory stock in the image memory is 3 seconds.

  Therefore, in the present embodiment, when the amount of image data (memory stock) accumulated in the image memory of the head 1 exceeds a predetermined threshold (here, 100%), the camera switching timing determination unit 116 moves the head 1 It is determined to retract from the substrate 20. In accordance with this determination, the mechanism control unit 111 retracts the head 1 from the substrate 20 and continues image processing at a position where the head 1 is retracted from the substrate 20. At the same time, the mechanism control unit 111 causes the head 2 to enter the substrate 20.

  The head 2 starts imaging from the next section of ID3 for which imaging has been completed by the head 1. As shown in FIG. 6A, the time required for the camera 104 of the head 2 to image the ID4 section is 5 seconds, and the memory stock at this time is 20% of the capacity of the image memory of the head 2. (Operation of head 2 (5)). Next, the time required to image the section of ID5 is 3 seconds, and the memory stock becomes 100% (operation (6) of the head 2).

  At this point, since the head 2 cannot continue imaging, the camera switching timing determination unit 116 determines to retract the head 2 from the substrate 20. At this point, the mechanism control unit 111 retracts the head 2 from the substrate 20 and causes the head 1 to enter the substrate. The mechanism control unit 111 continues the image processing of the memory stock at the position where the head 2 is retracted from the substrate 20. Since the image processing of the head 1 has already been completed at this point, the head 1 images the next section of ID6. The memory stock at this time is 60%, and the time required for the image capturing of ID6 is 5 seconds.

  In this case, in comparison with the case where the conventional inspection is performed with one head shown in FIG. 11, in order to inspect the same substrate, in the conventional case, 5 + 3 + 3 = 11 (seconds) for imaging the sections ID1, ID2, and ID3, the memory stock It takes 3 (seconds) to wait for image processing, 5 + 3 = 8 (seconds) to image ID4 and ID5, 3 (seconds) to wait for image processing of memory stock, and 5 (seconds) to image ID6. That is, a total of 30 (seconds) is required from the start to the end of the inspection of the substrate 20. In contrast, the inspection machine 100 according to the present embodiment requires 5 + 3 + 3 = 11 (seconds) to capture the sections ID1, ID2, and ID3. However, the head 2 performs ID4 in parallel with the image processing of the memory stock of the head 1. Since ID5 can be imaged at the same time, the entire inspection machine 100 does not have a waiting time for imaging.

  Further, since ID 6 can be imaged by the head 1 in parallel with the image processing of the memory stock of the head 2, the entire inspection machine 100 does not have a waiting time even if the memory stock of the head 2 becomes 100%. . This is because the image processing apparatus for the memory stock is completed in the head 2 in 3 seconds while the head 1 images the ID 6. In the head 1, 60% of the memory stock is generated by the imaging of ID 6, but the inspection of the substrate 20 is finished here, and the substrate 20 that has been inspected is unloaded from the inspection machine 100. In parallel with this carry-out operation, the image processing of the image data generated by the ID6 imaging is continuously executed by the mechanism control unit 111. Therefore, the time required for the image processing of the image data by the image pickup of ID6 does not become tact loss, and the inspection machine 100 according to the present embodiment inspects the substrate 20 in a total of 24 (seconds) from the start to the end of the inspection. Can be completed. That is, in the past, there was tact loss due to waiting for image processing of memory stock (3 seconds × 2 times), but in the inspection machine 100 of the present embodiment, this is eliminated, so that the time required for inspection of the same substrate is reduced. 6 seconds can be shortened.

  As described above, according to the inspection machine 100 of the present embodiment, when the memory stock of the head 1 exceeds the threshold value, the substrate 20 can be imaged in place of the head 2, so the memory stock of the head 1 can be captured. Image processing can be performed in parallel with the imaging of the substrate 20 by the head 2, and there is an effect that tact loss can be minimized.

  FIG. 7 is a flowchart for explaining the alternating operation of the head 1 and the head 2. The camera switching timing determination unit 116 includes a shared memory 60 that controls the head 1 and the head 2 that may enter the substrate 20. The shared memory 60 holds a value of MOVE. When MOVE = 1, the camera switching timing determination unit 116 and the mechanism control unit 111 retract the head 2 from the substrate 20 and move the head 1 into the substrate 20 when the head 2 is on the substrate 20. The substrate 20 is imaged. On the other hand, when MOVE = 2, when the head 1 is on the substrate 20, the head 1 is retracted from the substrate 20 and the head 2 is moved onto the substrate 20 to image the substrate 20.

  First, the camera switching timing determination unit 116 determines whether or not the inspection of the substrate 20 has been completed (S101, S201). If the inspection has been completed, the head 1 and the head 2 are retracted from the substrate 20 and the head 1 and the operation of the head 2 are terminated. If the inspection of the substrate 20 has not ended, the camera switching timing determination unit 116 determines whether or not the MOVE stored in the shared memory 60 is MOVE = 1 (S102, S202). For head 1, if MOVE = 1 is not satisfied (if MOVE = 2), the process returns to step S101 to determine whether or not the inspection of the substrate 20 has been completed. The head 1 is in a standby state by repeating the processes of step S101 and step S102 until MOVE becomes MOVE = 1. At this time, since MOVE = 2 for the head 2 (YES in S202), the camera switching timing determination unit 116 checks whether or not the memory stock of the head 2 has reached 100% (S203). If the memory stock of the head 2 is 100% (YES in S203), the camera switching timing determination unit 116 sets the value of MOVE in the shared memory 60 to MOVE = 1 (S204) and the mechanism control unit 111. Thus, the head 2 is retracted from the substrate 20, and the head 1 enters the substrate 20. The head 2 continues image processing at the position retracted from the substrate 20 (S205), and when the image processing of the head 2 is completed, the camera switching timing determination unit 116 returns to the processing of step S201. If the memory stock of the head 2 is not 100% in step S203, the mechanism control unit 111 controls the head 2 and becomes the inspection target this time in the ascending order of the numbers assigned to the IDs of the sections on the substrate 20. In the section, the head 2 is caused to perform imaging processing of the surface state of the substrate 20 such as the state of the mounted component and the printed state of the solder (S206). When the imaging process in this section by the head 2 is completed, the camera switching timing determination unit 116 returns to the process of step S201.

  If MOVE = 1 in step S102 for the head 1, the camera switching timing determination unit 116 checks whether the memory stock of the head 1 has reached 100% (S103). At this time, since MOVE = 2 is not satisfied in step S202 for the head 2, the camera switching timing determination unit 116 returns to the process in step S201 and checks whether or not the inspection of the substrate 20 has been completed. The head 2 is in a standby state until the MOVE is set to MOVE = 2 by repeating the processes of Step S201 and Step S202. For the head 1, the camera switching timing determination unit 116 sets the value of MOVE in the shared memory 60 to MOVE = 2 (S104) and the mechanism control if the memory stock is 100% (YES in S103). The head 1 is retracted from the substrate 20 by the unit 111, and the head 2 enters the substrate 20. The head 1 continues image processing at the position retracted from the substrate 20 (S105), and when the image processing of the head 1 is completed, the camera switching timing determination unit 116 returns to the processing of step S101. If the memory stock of the head 1 is not 100% in step S103, the mechanism control unit 111 controls the head 1 so that the section to be inspected this time is in ascending order of the numbers assigned to the section IDs on the substrate 20. For the inside, the head 1 is caused to perform imaging processing of the surface state of the substrate 20 such as the state of the mounted component and the printed state of the solder (S106). When the imaging process in the section by the head 1 is completed, the camera switching timing determination unit 116 returns to the process of step S101.

  As described above, by controlling the operations of the head 1 and the head 2, when the memory stock by the recognition of the head 1 becomes 100%, the head 1 is withdrawn from the substrate 20 and the image processing is continued. Can be made to enter the substrate 20 and the recognition process of the surface state of the substrate 20 can be executed in parallel, so that it is possible to suppress the occurrence of the head waiting time during the image processing of the memory stock, and to reduce the tact loss of the inspection machine 100. Can be reduced.

  FIG. 8A shows the relationship between the replacement timing of the head 1 and the head 2 and the amount of memory stock in the image memory when a head different from the example of FIG. It is a table | surface which shows. FIG. 8B is a timing chart showing the replacement timing of the head 1 and the head 2 when the head 1 and the head 2 inspect a substrate different from the example of FIG. 6B.

  Here, a case will be described in which a surface state of a substrate having a mounting state different from that of the substrate 20 shown in the inspection example in FIGS. 6A and 6B is inspected. As shown in FIG. 8A, in this board, for example, components with small sizes and components with small intervals between leads (electrodes) are concentrated in the sections of ID1, ID2, and ID3. It takes a long time.

  As described with reference to FIGS. 6A and 6B, the head 1 images the sections from ID1 to ID3, and stores the image data obtained by the imaging in the image memory (FIG. 8A). ) Head 1 operation (1) to (3)). Since the memory stock becomes 100% of the image memory of the head 1 after imaging the section of ID3, the mechanism control unit 111 retracts the head 1 from the substrate and continues image processing at the retracted position (FIG. 8 ( Operation (4)) of the head 1 in a).

  At the same time as the head 1 retreats from the substrate, the head 2 enters the substrate, images the next section ID4 and ID5, and stores the image data in the image memory (the head 2 in FIG. 8A). (5), (6)). At this time, the memory stock of the head 2 becomes 100% of the image memory. In the operation (4) of the head 1, the amount of memory stock is 100% of the image memory as in the case of FIG. 6A, but it takes 11 seconds to process this image. ing. For this reason, even if the memory stock of the head 2 becomes 100%, the imaging with the head 1 cannot be switched immediately, and a waiting state of 3 seconds occurs until the image processing of the head 1 is completed. Yes. In the operation (7) of the head 2, since the image processing of the memory stock takes 3 seconds, the timing when the head 1 wait state and the head 2 wait state end is the same. When the memory stock of the head 2 reaches 100%, the next imaging operation is switched to the head 1, so that the head 1 performs imaging in the next inspection target section ID 6 (operation (8) of the head 1). As in the example shown in FIGS. 6A and 6B, the head 1 generates 60% of memory stock due to the imaging of ID6, but the inspection of the substrate 20 ends here, and the inspection ends. The substrate 20 is unloaded from the inspection machine 100. In parallel with this carry-out operation, the image processing of the image data generated by the ID6 imaging is continuously executed by the mechanism control unit 111. Therefore, even in this case, the time required for image processing of image data by imaging of ID6 does not become tact loss.

  However, even in this case, compared with the case of inspecting with one head as in the prior art, in order to inspect the same substrate, in the past, 5 + 3 + 3 = 11 (seconds) for imaging the sections ID1, ID2, and ID3, It takes 11 (seconds) to wait for image processing, 5 + 3 = 8 (seconds) to capture ID4 and ID5, 3 (seconds) to wait for image processing of memory stock, and 5 (seconds) to capture ID6. That is, a total of 38 (seconds) is required from the start to the end of the inspection of the substrate 20. In contrast, the inspection machine 100 according to the present embodiment requires 5 + 3 + 3 = 11 (seconds) to capture the sections ID1, ID2, and ID3. However, the head 2 performs ID4 in parallel with the image processing of the memory stock of the head 1. , ID5 can be taken simultaneously. However, since the time required for imaging of ID4 and ID5 is 5 + 3 = 8 (seconds), the image processing of the head 1 takes a longer time, and both the head 1 and the head 2 wait for image processing. 3 (seconds) is generated. After this, 5 (seconds) is required for imaging of ID6 by the head 1, but the inspection can still be completed in a total of 27 (seconds) in the inspection machine 100 of the present embodiment.

  In the above example, the threshold for determining the switching of the head is set when the memory stock becomes 100% of the image memory. However, a long time is required for image processing in a part of the recognition target section. When necessary, it is impossible to perform imaging with any of the heads, resulting in a waiting time. Therefore, in the following, an example will be described in which a low threshold is set for determining the switching of the heads, thereby preventing waiting time from occurring at both heads simultaneously.

  In FIG. 9A, based on the mounting data indicating what parts are mounted in each section, the timing of changing the head 1 and head 2 is set earlier so that the waiting time is eliminated. It is a table | surface which shows the relationship between the timing of change in a case, and the memory stock amount in an image memory. FIG. 9B is a timing chart showing the replacement timing of the head 1 and the head 2 when the replacement timing of the head 1 and the head 2 is set earlier.

  As shown in FIG. 9A, first, the head 1 images the sections ID1 and ID2, and stores the image data obtained by the imaging in the image memory (operations (1) and (2) of the head 1). . At this time, the memory stock of the head 1 is 80% of the image memory, but the camera switching timing determination unit 116 sets 80% of the image memory as a camera switching threshold and does not wait for the memory stock to reach 100%. 1 is retracted from the substrate. The head 1 continues image processing at the retracted position (operation (3) of the head 1). The camera switching timing determination unit 116 and the mechanism control unit 111 simultaneously retract the head 1 from the substrate and simultaneously cause the head 2 to enter the substrate, thereby starting imaging and recognition of the substrate by the head 2.

  The head 2 images the sections ID3 and ID4, and stores the image data obtained by the imaging in the image memory (operations (4) and (5) of the head 2). At this point, the memory stock of head 2 is only 40% of the image memory. However, the camera switching timing determination unit 116 determines from the mounting data 114a that small parts or parts with small lead (electrode) intervals are concentrated in the ID5 section, and the head 2 is placed on the board. And the image processing is continued at the position after the retreat (operation (6) of the head 2). Then, the head 1 that has completed the image processing of the memory stock is caused to enter the substrate.

  As a result, the head 1 captures the section ID5 and stores the image data in the image memory (operation (7) of the head 1). As a result, the memory stock of the head 1 is 80% of the image memory. Also in this case, in the camera switching timing determination unit 116 and the mechanism control unit 111, components having a small size or components having a small interval between leads (electrodes) are concentrated in the section of ID6 from the mounting data 114a. I understand. At this time, the memory stock of the head 1 has reached the threshold value, and the head 2 has completed the image processing of the memory stock that occupies 40% of the image memory. 2 is determined, the head 1 is retracted from the substrate (operation (8) of the head 1), and the head 2 is moved onto the substrate. Thereby, the head 2 can take an image of the section of ID6 without going into a waiting state (operation (9) of the head 2). As a result, compared with the conventional case where the inspection is performed with one head, in order to inspect the same substrate, conventionally, the sections ID1 and ID2 are imaged, and 5 + 3 + 8 = 16 (seconds) for image processing of the memory stock. ), ID3 and ID4 are imaged and 3 + 5 + 3 = 11 (seconds) to image the memory stock, ID5 is imaged and memory stock image processing is 3 + 1 = 4 (seconds), and ID6 is imaged Takes 5 seconds. As a result, in contrast to the conventional inspection machine that requires a total of 36 (seconds) to inspect one substrate 20, in the inspection apparatus 100 of the present embodiment, the head 1 images the sections ID1 and ID2. 5 + 3 = 8 (seconds), but the head 2 can complete the imaging of ID3 and ID4 while image processing is performed on the image data obtained by imaging the sections ID1 and ID2. The time required for imaging ID3 and ID4 is 3 + 5 = 8 (seconds). Further, the head 1 images ID5 while performing image processing of the memory stock by imaging ID3 and ID4. The time required for imaging ID5 is 3 (seconds). While the image processing of the memory stock by the image pickup of ID5 is performed, the head 2 picks up the image of ID6 at 5 (seconds). Thus, in this example, the tact loss that both the head 1 and the head 2 are performing image processing of the memory stock is 0 (seconds), and the inspection can be completed in a total of 24 (seconds).

  As described above, when it is necessary to process high-resolution image data based on the mounting data 114a, the head 1 and the head that perform imaging before the image memory of the head in operation reaches 100%. By switching 2, tact loss can be minimized.

  In the above-described embodiment, the reference threshold value when switching between the head 1 and the head 2 has been described as 100% of the image memory. However, the present invention is not limited to this, and more such as 80% or 60%. It may be set to a low value.

  In the above-described embodiment, the camera switching timing determination unit 116 dynamically monitors the amount of memory stock stored in the image memory of each head 1 and head 2 and compares it with a threshold value. The case where the generation amount of the image data in the next section is predicted based on the above and the timing for switching the head 1 and the head 2 is determined has been described. However, the present invention is not limited to this, and the camera switching timing determination unit 116 may store a predetermined switching timing and switch the head 1 and the head 2 according to the read switching timing.

  That is, since it is known in advance which components are to be mounted in which section on each board, it is possible to determine the switching timing of the head 1 and head 2 in advance by performing a simulation or the like according to the mounting data. it can. Therefore, the camera switching timing determination unit 116 may store previously created data indicating the timing for switching between the head 1 and the head 2, and switch the head 1 and the head 2 according to the data. In this case, the method of actually switching between the head 1 and the head 2 is that when the head 1 is withdrawn and the head 2 enters the substrate, MOVE = 2 is set in the shared memory 60 and the head 2 is withdrawn. Can be executed by setting MOVE = 1 in the shared memory 60. As described above, the operation amount of the head 1 and the head 2 is switched according to the data indicating the switching timing created in advance, thereby reducing the calculation amount of the CPU for realizing the camera switching timing determination unit 116 and the cost of the inspection machine 100. There is an effect that can be suppressed.

  In the above embodiment, the inspection machine that inspects the mounting state of the component and the printed state of the solder after mounting the component on the board has been described. However, the inspection machine of the present invention inspects only the state after mounting the component. For example, the printed state of the cream solder may be inspected before mounting the component on the board.

  In this embodiment, only two heads have been described. However, the number of heads is not limited to two, and may be three or more.

  In the above embodiment, while one head is performing recognition on the substrate 20, it has been described that the other head is retracted from the substrate 20. However, the operation of the head being recognized is obstructed. It may be on the substrate 20 as long as it does not exist.

  Here, since the storage areas in the same storage unit 114 are allocated to the image memory here, the upper limit of the storage capacity, that is, the upper limit of the data amount of the image data is set to the head 1 and the head instead of actually allocating the storage area. It may be assigned to each of the two.

  Although the substrate inspection method of the present invention has been described based on the embodiment, the present invention is not limited to this embodiment. Unless it deviates from the meaning of this invention, the form which carried out the various deformation | transformation which those skilled in the art can think to this embodiment, and the structure constructed | assembled combining the component in different embodiment is also contained in the scope of the present invention. .

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be applied to a board inspection machine that inspects mounting of components by a component mounting machine, and in particular, to an inspection machine that performs processing on a substrate alternately by a plurality of inspection heads.

(A) is a figure which shows the external appearance of the component mounting system containing the test | inspection machine of this Embodiment. (B) is a plan view of the component mounting system shown in (a). It is a figure which shows the inspection method of the surface view of a test | inspection machine, and the surface state of a board | substrate. (A) is a diagram showing a state in which the head 2 is retracted from the substrate 20 while the head 1 recognizes the substrate 20. (B) is a diagram showing a state in which the head 2 replaces the head 1 and recognizes the substrate after the head 1 is retracted from the substrate. It is a block diagram which shows the structure with which the inspection machine of this Embodiment is provided. (A) is a figure which shows alternate operation | movement of the two heads in an inspection machine. (B) is a figure which shows an example of the division used as the unit of recognition of the camera in the case of performing an alternating inspection with two heads. FIG. 5A is a table showing the relationship between the inspection head replacement timing and the amount of memory stock in the image memory when the sections shown in FIG. FIG. 5B is a timing chart showing the timing of changing the inspection head when the sections shown in FIG. 4 is a flowchart for explaining an alternate operation of a head 1 and a head 2. (A) is a table | surface which shows the relationship between the timing of replacement | exchange of a test | inspection head in the case of test | inspecting the board | substrate different from the example of Fig.6 (a) with the head 1 and the head 2, and the memory stock amount in an image memory. . FIG. 6B is a timing chart showing the timing of changing the inspection head when the head 1 and the head 2 inspect a substrate different from the example of FIG. (A) shows the replacement timing when the inspection head replacement timing is set earlier and adjusted so that the waiting time is eliminated based on mounting data indicating what components are mounted in each section. 4 is a table showing the relationship between the memory stock amount in the image memory. (B) is a timing chart showing the timing of inspection head replacement when the timing of inspection head replacement is set earlier. (A) is a top view of the conventional 1-head inspection machine. (B) is a figure which shows an example of the imaging order at the time of the conventional test | inspection machine test | inspecting the components on a board | substrate. (A) is a figure which shows an example of the relationship between each tact when the area on a board | substrate is imaged in order shown in FIG.10 (b), and recognition is performed, and the memory stock amount of image data. FIG. 10B is an example of a timing chart of the inspection machine when the sections on the substrate are imaged and recognized in the order shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Head 20 Board | substrate 60 Shared memory 100, 900 Inspection machine 102 Display part 103 Input part 104 Camera 111 Mechanism control part 114 Storage part 114a Mounting data 115 Communication I / F part 116 Camera switching timing determination part 120 Mechanism part 902 Conveyor rail 903, 904 beams

Claims (5)

A board inspection method for inspecting a surface state of a board including a component mounting state or a solder printing state by imaging the board with an inspection head equipped with a camera and analyzing the captured image,
A plurality of test heads having one camera for imaging the substrate, respectively, a predetermined region on the substrate and the image shooting alternately, in parallel with the image processing of the image processing and image taken Done
Accumulating image data generated by imaging the area for each inspection head;
Depending on the amount of the image data accumulated for the inspection head being imaged, the inspection head determines whether or not it is necessary to interrupt imaging, and if it is determined that it is necessary to interrupt other inspection A method for inspecting a substrate, wherein imaging is performed on a head and image processing of the accumulated image data is performed . A board inspection method for inspecting a surface state of a board including a component mounting state or a solder printing state by imaging the board with an inspection head equipped with a camera and analyzing the captured image,
A plurality of inspection heads each having one camera for imaging a substrate are used to alternately image a predetermined area on the substrate, and imaging processing and image processing of the captured image are performed in parallel. ,
Each inspection head is assigned an image memory, which is a storage area for storing the image data generated by imaging by each camera, and a CPU function for image processing the image data in the image memory. ,
The camera of one inspection head images the substrate, and the function of the CPU assigned to the inspection head performs image processing on the image data generated by the imaging,
It is determined whether or not image data that has not undergone image processing is stored in a predetermined amount or more in the image memory assigned to the one inspection head. Is removed from the substrate to stop imaging, and the CPU function is allowed to continue the image processing of the image data in the image memory assigned to the inspection head, and one of the other inspection heads is method of inspecting board characterized in that to start imaging by entering on the substrate. The substrate inspection method includes:
Pre-installed data is stored in advance in the memory to indicate at least what part is mounted on the board and what kind of solder is printed on which position on the board.
Even when it is determined that the amount of image data that has not been subjected to image processing and is stored in the image memory allocated to the one inspection head is less than the predetermined amount, the mounting data is Referring to the amount of image data for which image processing has not been completed by imaging a region to be imaged exceeds the predetermined amount or is longer than a predetermined time for image processing of image data generated by imaging 3. The method according to claim 2 , wherein if it is determined that the inspection is required, the inspection head is retracted from the substrate to stop imaging, and one of the other inspection heads enters the substrate to start imaging. Board inspection method. A board inspection apparatus for inspecting a surface state of a board including a component mounting state or a solder printing state by imaging the board with an inspection head equipped with a camera and analyzing the captured image,
Each comprising a plurality of said testing head having one camera for imaging a substrate, a plurality of the inspection head, and an image shooting a predetermined region on the substrate alternately imaged processed and imaging Perform image processing in parallel with the image,
Each inspection head accumulates image data generated by imaging the area for each inspection head;
Each inspection head determines whether or not the inspection head needs to interrupt imaging according to the amount of the image data accumulated for the inspection head being imaged, and determines that it is necessary to interrupt In this case, the substrate inspection apparatus is characterized in that the image processing is performed on the stored image data by changing the imaging to another inspection head . The computer to perform the method of inspecting a substrate according to claim 1, recorded on a computer-readable recording medium programs.

Images