JP7621156B2 - Mold Monitoring Device - Google Patents

Description

The invention of this application relates to a mold monitoring device that monitors molds in molding devices used to mold various articles.

Conventionally, molding devices equipped with molds have been used to mold various articles. For example, in an injection molding machine, which is one type of molding device, a thermoplastic resin is heated to soften it, filled into a mold, and then cooled to mold an article of a desired shape. A set of one or more molds is used as the mold. For example, a pair of molds consisting of a fixed mold and a movable mold is used. Hereinafter, the molding process in which material is filled into a mold in this way is referred to as a molding cycle.

In such molding devices, it is often necessary to monitor the mold. For this reason, a mold monitoring device is used. A mold monitoring device has a camera that takes pictures of the inside of the mold, and a judgment unit that processes the images taken by the camera and judges whether the molding situation is normal or abnormal. The camera is often installed in a position where it can take pictures of the inside of the movable mold.

There are two main reasons for monitoring molds with cameras. One reason is to monitor the molding status after molding, while the article is held in the mold. This type of monitoring is called primary monitoring. In primary monitoring, the shape of the article on the mold is checked to determine whether it has been molded correctly. If the article has a chip or other defect and is determined to be an incorrect shape, the primary monitoring results in an abnormality, and the mold monitoring device outputs a primary monitoring abnormality.
The output of the mold monitoring device is input to the main control unit of the molding device, and when a primary monitoring abnormality is output, the main control unit controls the molding device to stop operation. Then, an operator investigates the cause of the incorrect molding.

Another purpose of mold monitoring is mainly for the next molding, to check whether the mold opens after molding and the item is properly removed. This type of monitoring is called secondary monitoring. In secondary monitoring, images of the inner surface of the mold are used to determine whether the item has not been properly removed and remains, or whether some material has remained. If the item has not been released or some material has remained, a secondary monitoring abnormality is output, and control is exercised to stop the operation of the molding device in the same way.

Patent No. 6584472 Patent No. 6798794

In the conventional mold monitoring device described above, primary and secondary monitoring are performed using still images at the respective times. However, monitoring using still images alone can cause problems, such as insufficient monitoring or inability to fully grasp the situation when an abnormality occurs. Therefore, it is considered to use video for monitoring.

However, when monitoring using video, the data size sent from the camera becomes enormous, and unless the timing of video capture is set appropriately, monitoring and analysis of abnormalities becomes difficult. The invention of this application aims to solve this problem, and aims to prevent the amount of data from becoming excessive and to enable sufficient analysis of abnormalities by appropriately setting the timing of video capture in mold monitoring using video.

In order to solve the above problems, the mold monitoring device disclosed in this specification is a mold monitoring device that monitors the inside of the molds that are opened after molding, in a molding apparatus in which a set of molds, at least one of which is a movable mold, is closed while an article is molded inside the molds and then the molds are opened to remove the article, and is equipped with a camera that is pointed toward the inside of the open molds and is capable of taking video, a control unit that controls the start and stop of video recording by the camera, and a judgment unit that judges whether the molding condition is normal or abnormal based on an image of the inside of the molds taken by the camera or another camera.
This mold monitoring device is provided with a video shooting span setting unit that sets the timing for starting and ending video shooting by the camera during one molding cycle, and the control unit controls the start and end of shooting by the camera in accordance with the settings in the video shooting span setting unit.
The setting in the video capture span setting section is set to a time width greater than zero based on the timing at which the determining section determines whether the molding state is normal or abnormal.
In addition, in order to solve the above problem, this mold monitoring device can be configured so that the timing at which the judgment unit judges whether the molding state is normal or abnormal is the timing of primary monitoring after the mold is opened and before the item removal operation is performed, and the timing at which shooting in the video shooting span setting unit starts is prior to the timing of primary monitoring and is the timing at which the operation to open the mold is started or earlier.
In addition, in order to solve the above problem, this mold monitoring device can be configured so that the timing at which the judgment unit judges whether the molding state is normal or abnormal is the timing of secondary monitoring that is performed after the item removal operation, the timing at which shooting in the video shooting span setting unit starts is the timing at which the item removal operation starts or earlier, and the timing at which shooting ends is the timing of secondary monitoring or later.
In addition, in order to solve the above problems, this mold monitoring device can be configured so that the timing for ending photographing is set to end at the point when it is determined that the secondary monitoring is normal, and is set to extend photographing by a predetermined time width if it is determined that the secondary monitoring is abnormal.
In addition, in order to solve the above problem, this mold monitoring device may be configured so that the judgment unit performs secondary monitoring again after an abnormality is determined to exist at the timing of the first secondary monitoring following the item removal operation, and the timing for ending shooting in the video shooting span setting unit is set so that shooting ends at the point when the second or subsequent secondary monitoring is determined to be normal, and is set so that shooting is extended by a predetermined time width if an abnormality is determined.
In addition, in order to solve the above problem, the mold monitoring device can be configured so that a camera photographs the inside of a movable mold, and is installed so that both the start position and the end position of the movement of the movable mold when the mold is opened are within the photographing area.
In addition, in order to solve the above problems, this mold monitoring device may be configured so that multiple cameras are provided so as to simultaneously capture multiple locations inside the mold, and the timing for starting and ending shooting in the video shooting span setting unit is set as a common timing for each camera.

As described below, according to the mold monitoring device of the disclosed invention, a video of the mold being monitored is taken and stored in a memory unit, so that analysis can be performed more effectively when an abnormality occurs. In this case, the video becomes one video file for one molding, so that file management in the memory unit is easy. Also, instead of having the camera keep rolling all the time, the video is taken at a span (start and end) based on the timing of the mold monitoring, so that the amount of video data does not become unnecessarily excessive, and analysis can be performed sufficiently using the video when an abnormality occurs.
Furthermore, if the timing for starting filming is before the timing of primary monitoring and at or before the timing when the mold opening operation begins, this is useful for analyzing how the mold opening operation is related to an abnormality that is determined to be present in the primary monitoring.
In addition, if the timing for starting photographing is the timing when the item removal action begins or before, and the timing for ending photographing is the timing for secondary monitoring or after, it is useful for analyzing how the removal action is related to an abnormality that is determined in secondary monitoring.
Furthermore, in a configuration in which if the secondary monitoring determines that the condition is normal, recording is set to end at that point, and if the secondary monitoring determines that the condition is abnormal, recording is set to be extended for a specified period of time, it becomes possible to more thoroughly analyze cases in which the secondary monitoring determines that the condition is abnormal, while preventing the amount of video data from becoming excessive.
In addition, if an abnormality is determined to be present during the first secondary monitoring following the item removal operation, secondary monitoring is performed again, and if an abnormality is determined to be present during the second or subsequent secondary monitoring, photographing is extended. This configuration makes it possible to prevent a secondary monitoring abnormality from being output in the case of a minor malfunction, and makes it possible to more thoroughly analyze cases in which an abnormality is determined to be present during the second or subsequent secondary monitoring.
Furthermore, if the camera is positioned so that both the start and end positions of the movement of the movable mold when opening the mold are included in the shooting area, the entire movement of the movable mold will be captured in the video, which is particularly suitable for analyzing the relationship of abnormalities to the mold opening operation.
In addition, in a configuration in which multiple cameras are provided and the start and end timings of shooting in the video shooting span setting unit are set as common timings for each camera, monitoring of large molds can be performed appropriately while obtaining the above-mentioned effects.

1 is a schematic plan view of a mold monitoring device according to a first embodiment. FIG. FIG. 11 is a schematic diagram showing a span of moving image shooting input as setting information. 13 is a schematic diagram showing an example of a movie shooting span setting window displayed by the setting information input program. FIG. 4 is a schematic diagram of a monitoring sequence program implemented in the mold monitoring device of the embodiment. FIG. 13 is a schematic diagram showing a main part of a mold monitoring device according to a second embodiment, and a flowchart showing an outline of a main part of a monitoring sequence program according to the second embodiment. FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will now be described with reference to the accompanying drawings. FIG 1 is a schematic plan view of a mold monitoring device according to a first embodiment of the present invention.
The mold monitoring device shown in Fig. 1 includes cameras 1a and 1b capable of taking moving images, and a device main body 2 including a control unit that controls the start and stop of taking moving images by the cameras 1a and 1b. The molding device 9 includes a movable mold 91, a fixed mold 92, a moving mechanism 93 that moves the movable mold 91, a material injection system 94 that injects material into the closed molds 91 and 92, a main control unit 90 that controls each part, etc. In addition, although not shown, it includes an ejection mechanism that performs an ejection operation to remove an article after molding, etc.

In this embodiment, cameras 1a and 1b are attached so as to photograph the inner surface of movable mold 91 of molding device 9. In this embodiment, two cameras 1a and 1b are provided, each of which photographs a different area inside movable mold 91. Each camera 1a and 1b is equipped with an image sensor with, for example, about 2 to 3 million pixels, and may be monochrome, but color is more preferable.

In addition, in FIG. 1, the cameras 1a and 1b are depicted as being attached to the fixed mold 92, but they may be attached to a pedestal or the like installed separately from the fixed mold 92. Also, since FIG. 1 is a schematic plan view, the cameras 1a and 1b face the movable mold 91 from an oblique side, but they may be attached to the top surface of the fixed mold 92 and face the movable mold 91 from an oblique top. The cameras 1a and 1b photograph the inner surface of the movable mold 91, but when a molded article is held in that portion, the inner surface is covered by the article and the camera photographs the article.

As described below, the shooting span of each camera 1a, 1b is set so that it captures a video of the opening operation of the movable mold 91. Therefore, each camera 1a, 1b is installed and the shooting area is adjusted so that the position of the movable mold 91 in the closed state and the position of the movable mold 91 in the open state are included in the shooting area. The shooting area in this case is the shooting area when the posture of each camera 1a, 1b is fixed.

The device body 2 includes a control unit that controls the shooting of the cameras 1a and 1b, as well as a judgment unit that judges whether the molding state is normal or abnormal. In this embodiment, the device body 2 is a portable computer device equipped with a processor 21, a display 22, an input/output interface 23, etc. Specifically, for example, a tablet PC equipped with a display of about 10 to 12 inches can be used as the device body 2.

The device body 2 has a storage unit 3 such as an SSD or HDD. The storage unit 3 stores a monitoring sequence program 31 including control of the operation of the cameras 1a and 1b, video files 32 captured by the cameras 1a and 1b, monitoring programs 331 and 332 that perform primary and secondary monitoring based on images captured by the cameras 1a and 1b, and reference image files 341 and 342 referenced by the monitoring programs 331 and 332. In addition, the storage unit 3 stores a setting information file 35 that records various setting information and a setting information input program 36 for inputting setting information. Therefore, in this embodiment, the control unit is composed of the device body 2 and the monitoring sequence program 31 implemented in the device body 2. The judgment unit is composed of the device body 2 and the monitoring programs 331 and 332 implemented in the device body 2.

The display 22 also functions as a touch panel and serves as an input section for setting information, and the setting information input program 36 is a program that displays an input screen on the display 22 and records the input setting information in the setting information file 35.
The mold monitoring device is connected to the main control unit 90 of the molding device 9, and when an abnormality is detected in the primary or secondary monitoring, it outputs a message to the main control unit 90 via the input/output interface 23. Each of the monitoring programs 331, 332 is a program that compares the images (still images) sent from the cameras 1a, 1b with a reference image and judges whether the images are normal or abnormal based on the difference.

Next, the setting information of the span of video shooting by the cameras 1a and 1b, which is a major feature of the mold monitoring device of the embodiment, will be described. Fig. 2 is a schematic diagram showing the span of video shooting input as setting information.
As shown in Fig. 2, the span of video shooting is set based on the primary monitoring timing t1 and the secondary monitoring timing t2. Specifically, the start timing of video shooting is set to be the same as or earlier than the primary monitoring timing t1. In other words, the time lag from the start of video shooting to the primary monitoring (shown as T1 in Fig. 2) may be zero. Hereinafter, this time lag T1 is referred to as the shooting start advance time.

The timing for the end of video recording is set to a timing later than the secondary monitoring timing t2. In FIG. 2, the time lag from the secondary monitoring timing t2 to the end of video recording is indicated as T2. Hereinafter, this time lag T2 will be referred to as the recording end delay time. These video recording span setting information are set by being input in advance using the setting information input program 36.

Figure 3 is a schematic diagram showing an example of a video capture span setting window displayed by the setting information input program 36. As shown in Figure 3, the video capture span setting window has a capture start advance time input field 41 and a capture end delay time input field 42. The capture start advance time input field 41 is a field for inputting the advance time from the timing of primary monitoring as a numerical value (seconds) (0 can be entered). The capture end delay time input field 42 is a field for inputting the delay time from the timing of secondary monitoring as a numerical value (seconds) (0 cannot be entered).

In this embodiment, it is possible to select whether or not to delay the end of shooting depending on whether an abnormality is output in secondary monitoring. Specifically, the setting information input screen has an option input field 43 for delaying the end of shooting. The option input field 43 is a field for selecting whether or not to delay the end of shooting if an abnormality is detected in secondary monitoring. When these input fields are filled in and the OK button 44 is pressed, the setting information input program 36 records the input information in the setting information file 34.

Next, a monitoring sequence program 31 for operating the mold monitoring device in a predetermined sequence based on the preset information will be described. Fig. 4 is a schematic diagram of the monitoring sequence program 31 implemented in the mold monitoring device of the embodiment.
1 is configured to receive signals indicating the operating status of the molding device 9. The monitoring sequence program 31 is always in an executed state while the molding device 9 is in operation, and in a standby state, is in a state of waiting for input of an operating status signal from the molding device 9.

The time from when molding is started to the timing t1 of primary monitoring is given as a constant to the monitoring sequence program 31. This time includes the time from when the set of dies 91, 92 are closed to when they are opened, that is, the time from when the dies 91, 92 are closed, when the material is injected, to when solidification is completed, and is a little longer than that. Hereinafter, this time is called molding time, and is indicated by Tm in FIG. 2.
The monitoring sequence program 31 starts a timer count when it receives a signal indicating that the dies 91, 92 are closed at a certain time. Hereinafter, this signal indicating that the dies 91, 92 are closed will be referred to as a molding start signal.

When the timer count reaches the molding time Tm - the advance time T1 for the start of image capture, the monitoring sequence program 31 sends a control signal to cameras 1a and 1b to start image capture. Then, when the timer count reaches the molding time Tm, the monitoring sequence program 31 acquires still images at that time from the video sent from cameras 1a and 1b, and passes them as arguments to the primary monitoring program 331 to perform primary monitoring.

The primary monitoring is performed by each of the cameras 1a and 1b. For convenience of explanation, the two cameras will be referred to as a first camera 1a and a second camera 1b below.
The primary monitoring program 331 compares a still image taken from the video of the first camera 1a with a reference image for primary monitoring for the first camera 1a. It then determines whether the difference is within a limit, and if so, the primary monitoring for the first camera 1a is deemed normal. If the difference exceeds the limit, the primary monitoring for the first camera 1a is deemed abnormal. Next, the primary monitoring program 331 compares a still image taken from the video of the second camera 1b with a reference image for primary monitoring for the second camera 1b, and determines whether the difference is within a limit. If the difference is within the limit, the primary monitoring for the second camera 1b is deemed normal, and if so, the primary monitoring for the second camera 1b is deemed abnormal.
If the result of the monitoring sequence program 31 is abnormal for either of the cameras 1a and 1b, the monitoring sequence program 31 outputs a primary monitoring abnormality to the main control unit 90 of the molding device 9. At this time, information indicating which of the cameras 1a and 1b showed the abnormal result is also output.

On the other hand, the time from the timing of the primary monitoring to the timing of the secondary monitoring is given as a constant to the monitoring sequence program 31. This time includes the time required for the pushing-out operation. Hereinafter, this time will be referred to as the pushing-out time, and is indicated by Tp in FIG. 2.
At the time of primary monitoring, the monitoring sequence program 31 resets the timer count to 0 and restarts it. Then, when the timer count reaches the protrusion time Tp, the monitoring sequence program 31 acquires still images from the video sent from the cameras 1a and 1b at that time, passes them as arguments, and executes the secondary monitoring program 332 to perform secondary monitoring.

The secondary monitoring program 332 compares the still image acquired from the video of the first camera 1a with the secondary monitoring reference image for the first camera 1a, and determines whether the difference is within a limit. If it is within the limit, the secondary monitoring for the first camera 1a is normal. If it exceeds the limit, the secondary monitoring for the first camera 1a is abnormal.
Next, the secondary surveillance program 332 compares the still image extracted from the video of the second camera 1b with the secondary surveillance reference image for the second camera 1b and determines whether the difference is within a limit. If it is within the limit, the secondary surveillance for the second camera 1b is deemed normal, and if it exceeds the limit, it is deemed abnormal.

Then, if the result of the monitoring sequence program 31 is abnormal for either of the cameras 1a and 1b, the monitoring sequence program 31 outputs a secondary monitoring abnormality to the main control unit 90 of the molding device 9. At this time, information indicating which of the cameras 1a and 1b showed the abnormal result is also output.
4, when the result of the secondary monitoring is normal (when both the cameras 1a and 1b are normal), the monitoring sequence program 31 transmits a control signal for ending image capture to the cameras 1a and 1b. Whether the result of the secondary monitoring is normal or abnormal, the monitoring sequence program 31 resets the timer count to 0.

In the case of a secondary monitoring abnormality, the monitoring sequence program 31 restarts the timer count without sending a control signal for ending the image capture to the cameras 1a and 1b. After that, when the timer count reaches the image capture end delay time T2, the monitoring sequence program 31 sends a control signal for ending the image capture to the cameras 1a and 1b. Then, the timer count is stopped and reset to 0.
This completes the monitoring sequence for one molding cycle, and the monitoring sequence program 31 enters a state of waiting for the next molding start signal.

As an example of each time, for example, the image capture start advance time T1 is set to 5 seconds, and the primary monitoring is set to be performed 1 second after the completion of the opening operation of the movable mold 91. The time required for the opening operation of the movable mold 91 is about 3 seconds, and the image capture starts about 1 second before the opening operation of the movable mold 91 starts.
Furthermore, the protruding time Tp is set to, for example, 5 seconds. The protruding operation starts immediately after the primary monitoring timing and is completed about 2 to 3 seconds before the secondary monitoring timing. The protruding operation itself takes about 1 to 2 seconds. The shooting end delay time T2 is set to, for example, 5 seconds. The video shooting ends at the earliest at the secondary monitoring timing, so in either case, video shooting ends after the protruding operation is completed.

Although the explanation is omitted, the above example is a case where video recording is extended when a secondary monitoring abnormality occurs. This setting information is set by the setting information input program 36 as described above, and this setting information is passed as an argument when the monitoring sequence program 31 is started.
In the above monitoring sequence, if an abnormality is output in the primary monitoring, the molding device 9 is usually put into a state of operation stop. In this case, an end of photography signal is output at that point, photography ends, and secondary monitoring is not performed. However, photography may be continued. If it is continued, photography ends when the timer count reaches the protrusion time Tp, and the timer count is reset to zero.

In the above monitoring sequence, primary monitoring may be performed when a signal indicating that the movable mold 91 is open is sent from the molding device 9. In this case, too, the video capture start signal is sent to cameras 1a and 1b when the time Tm-T1 has elapsed since the timer started counting.

As can be seen from the above description, in the monitoring sequence, one video file 32 is generated and stored for one molding cycle and one camera. The storage unit 3 is provided with a folder for storing the video file 32.
The folder for storing the video file 32 is divided into a folder for storing the video file 32 when the mold monitoring is normal (hereinafter, the normal folder) and a folder for storing the video file 32 when the mold monitoring is abnormal (hereinafter, the abnormal folder). Furthermore, the abnormal folder has a subfolder for the first camera 1a and a subfolder for the second camera 1b.

When an abnormality occurs in the mold monitoring, each video file 32 is stored in the abnormality folder for the corresponding camera. That is, when an abnormality occurs in the first camera 1a, the video file 32 is stored in the abnormality folder for the first camera 1a, and when an abnormality occurs in the second camera 1b, the video file 32 is stored in the abnormality folder for the second camera 1b. At this time, each video file 32 is stored with the date and time when the video was shot (the start date and time of shooting or the end date and time of shooting) as the file name.
The moving image file 32 when both the first and second die monitoring are normal may be stored in a normal folder without using the shooting date and time as the file name and be constantly overwritten. Alternatively, an upper limit may be set on the size of the normal folder, and when the upper limit is reached, the oldest moving image file 32 may be deleted.
In addition, when an abnormality occurs, each video file 32 may be stored in the same folder with a file name that allows distinction between the video captured by the first camera 1a and the video captured by the second camera 1b. This also applies to the video file 32 when normal.

The overall operation of the mold monitoring device of this embodiment and the overall operation of the molding device 9 will be described below.
In a manufacturing line for an article in which molding is performed using a molding device 9, an operator inputs necessary setting information to a mold monitoring device. The setting information includes molding time Tm, ejection time Tp, advance time T1 for starting image capture, and delay time T2 for ending image capture. Then, the mold monitoring device is operated to perform molding using the molding device 9.

The molding device 9 injects material into the molds 91 and 92 while the set of molds 91 and 92 is closed. At this time, a molding start signal is sent to the mold monitoring device. Upon receiving the molding start signal, the mold monitoring device starts counting on a timer.
When the set molding time Tm has elapsed, the molding device 9 moves the movable mold 91 to open the molds 91, 92. During this time, when the time (molding time Tm - shooting start advance time T1) has elapsed, a shooting start signal is sent to the cameras 1a, 1b, and the cameras 1a, 1b start shooting video. Then, immediately after the molds 91, 92 are opened, the mold monitoring device performs primary monitoring. That is, still images at the time of primary monitoring are obtained from the data of each video sent from the cameras 1a, 1b, and each is compared with a reference image to judge whether the molding situation is normal or abnormal.

If an abnormality is determined as a result of the primary monitoring, a notice to that effect is sent to the main control unit 90 of the molding device 9. This causes the main control unit 90 to operate and interrupt the molding cycle.
If no primary monitoring abnormality is output, the molding device 9 performs an ejection operation, whereby the article is ejected and removed from the molds 91 and 92.

Meanwhile, the timer of the mold monitoring device is reset to 0 at the timing of primary monitoring and restarted. When the timer count reaches the ejection time Tp, the mold monitoring device stops the timer count, resets it to 0, and performs secondary monitoring. That is, still images at the ejection time Tp are obtained from each video sent from cameras 1a and 1b, and each is compared with a reference image to determine whether the molding situation is normal or abnormal.

If the secondary monitoring is judged to be normal, the mold monitoring device outputs a control signal to end image capture to the cameras 1a and 1b. If the secondary monitoring is judged to be abnormal, the mold monitoring device outputs a message to that effect to the main control unit 90 of the molding device 9 and restarts the timer count. Then, when the timer count reaches the image capture end delay time T2, the mold monitoring device sends a control signal to end image capture to the cameras 1a and 1b.
On the other hand, the main control unit 90 of the molding device 9 that has received the output of the secondary monitoring abnormality stops the next molding cycle and keeps the dies 91, 92 open. If the secondary monitoring is normal, the molding device 9 closes the dies 91, 92 again, injects material, and performs the next molding cycle.

In the above operation, if the primary monitoring detects an abnormality and the molding device 9 stops operating, the worker investigates the situation. At this time, in addition to checking the molds 91, 92, the worker also plays the video file 32 stored in the mold monitoring device and checks the video. The cause of the primary monitoring abnormality is then identified and necessary measures are taken. The same applies if an abnormality is detected in the secondary monitoring; the molds 91, 92 are checked, the video from the mold monitoring device is checked, and necessary measures are taken. The device main body 2 is equipped with a program for playing the video file 32 on the display 22, and this program is used when checking the video.

According to the embodiment of the mold monitoring device relating to the above operation, video is taken of the molds 91, 92 undergoing primary and secondary monitoring and stored in the memory unit 3, so that analysis can be performed more effectively if an abnormality occurs during primary or secondary monitoring.
In this case, the moving image becomes one moving image file 32 for one molding cycle, so that file management in the storage unit 3 is easy. For example, if a lot number is assigned to each molding cycle in the molding device 9, each moving image file 32 can be managed in correspondence with this lot number.

In addition, rather than having the cameras 1a and 1b constantly rotate, video is taken at spans (start and end) based on the timing of the mold monitoring, so the amount of video data does not become unnecessarily excessive. In other words, video can be saved only during the time periods required for primary and secondary monitoring, making it possible to save the storage area of the storage unit 3 for saving video while saving the necessary video. This makes it possible to fully analyze abnormalities by utilizing the video.

The fact that there is one video file 32 for one molding cycle is significant in that it makes it easy to identify the video file 32 for the molding cycle in which an abnormality occurred. That is, the date and time when the mold monitoring device output an abnormality and the molding operation was stopped is saved in the main control unit 90 of the molding device 9. Therefore, the video file 32 with the date and time closest to this date and time in its file name is the video file 32 when the abnormality occurred, and by playing back this video file 32, it is possible to check the video of how the abnormality occurred.

In addition, in this embodiment, since the video recording can be started at any time before the timing of the primary monitoring, a video of an appropriate span can be stored in relation to the opening operation of the movable mold 91. For example, by setting the advance time T1 for the start of recording to be a time slightly longer than the time required for the movable mold 91 to open, the entire situation of the mold opening can be captured in the video. This is of great significance in analyzing the occurrence of a primary monitoring abnormality. In other words, the video can be used to analyze whether the opening operation of the movable mold 91 is related to the cause of the occurrence of a primary monitoring abnormality. In this case, the advance time for the start of video recording can be set to match the time required for the movable mold 91 to open, so that the analysis of the primary monitoring abnormality is optimized according to the molding of various articles and various molding devices 9.

In relation to the above, in this embodiment, the cameras 1a and 1b are installed so that both the start and end positions of the movement of the movable mold 91 during the opening operation of the molds 91 and 92 are included in the shooting area. This is also of great significance. In other words, all of the movement of the movable mold 91 is captured in the video, which is particularly suitable for analyzing the relationship of anomalies to the opening operation.

In addition, when an abnormality occurs in the secondary monitoring, the video recording is extended by the delay time for the end of the recording, which is very useful for checking the situation when the abnormality occurs in the secondary monitoring and the situation afterwards. In particular, when a secondary monitoring abnormality is output, if an operator goes to the molds 91, 92 to investigate, the object may be correctly ejected and not abnormal. This situation is often the case when the object is caught on the movable mold 91 at the time of secondary monitoring and is deemed abnormal, but then falls off, and is in a normal state when the operator arrives. In this case, such a situation cannot be determined by just looking at the still image at the time of secondary monitoring, but it can be immediately identified by looking at the video after secondary monitoring. In this way, the mold monitoring device of the embodiment can analyze the situation when an abnormality occurs in each mold monitoring in more detail and accurately.

Next, a description will be given of a mold monitoring device according to a second embodiment of the present invention. Fig. 5 is a schematic diagram showing the main parts of the mold monitoring device according to the second embodiment of the present invention, and a flow chart showing the main parts of a monitoring sequence program according to the second embodiment of the present invention.
In the mold monitoring device of the second embodiment, if an abnormality is determined in the secondary monitoring, a configuration is adopted in which the secondary monitoring is performed again after a time has elapsed. To be more specific, as shown in Fig. 5, in the second embodiment, if an abnormality is determined in the secondary monitoring, at this point in time, no secondary monitoring abnormality is output to the main control unit 90 of the molding device 9, and the timer count is reset to zero and then restarted. Also, at this point in time, a photography end signal is not output to each of the cameras 1a and 1b, and photography is extended.

Then, when the timer count reaches a predetermined value (hereinafter referred to as the second monitoring time T3), the monitoring sequence program 31 executes the secondary monitoring program 332 by passing the still images acquired from the video of each camera 1a, 1b at that time as arguments. If the execution result of either camera is judged to be abnormal, a secondary monitoring abnormality is output to the main control unit 90 of the molding device 9. If the execution result of either camera is judged to be normal, a secondary monitoring abnormality is not output to the main control unit 90. If an abnormality is detected in the second secondary monitoring, similarly, the shooting end signal is not output at that time, and the shooting end signal is output when the shooting end delay time T2 has elapsed.
The second monitoring time T3 is shorter than the image capture end delay time T2 extended after the first secondary monitoring, so that image capture is not interrupted. For example, if the image capture end delay time T2 is 5 seconds, the second monitoring time T3 is set to 2 seconds.

In the second embodiment, even if secondary monitoring detects an abnormality, secondary monitoring is performed again after a specified time has elapsed, and if it is still determined to be abnormal, a secondary monitoring abnormality is output to the main control unit 90 of the forming device 9. This eliminates the problem of outputting a secondary monitoring abnormality even in the case of a minor malfunction, such as an article being slightly caught during ejection and falling naturally within a short time. In this case, too, the occurrence of such a minor malfunction can be confirmed later on in a video, so appropriate measures can be taken for the minor malfunction, and it is possible to prevent the situation from developing into one in which an abnormality is detected in the second secondary monitoring as well.

In addition, video files 32 that are determined to be abnormal in the first secondary monitoring but are normal in the second secondary monitoring are also stored in the abnormality folder in the storage unit 3. In this case, it is preferable to save the video files in a folder separate from the folder in which the first secondary monitoring was determined to be abnormal, as this makes subsequent analysis easier.

In the second embodiment, if an abnormality is detected in the second secondary monitoring, it is also useful for later analysis to further extend the imaging end delay time T2. For example, in the above example, if the re-secondary monitoring time T3 is 2 seconds and an abnormality is detected at that time, the timer is reset to zero and another imaging end delay time of 5 seconds is provided. In this example, the imaging end delay is 7 seconds from the timing of the first secondary monitoring.
If the secondary monitoring also detects an abnormality, a configuration may be adopted in which a third or subsequent secondary monitoring is performed after a second secondary monitoring time T2 has elapsed. In this case, if an abnormality is detected in the second secondary monitoring, the imaging end delay time T2 is further added to extend imaging, so that imaging is not interrupted until the third or subsequent secondary monitoring.

In each of the above-described embodiments, a method using a color image can be adopted as the primary monitoring method or the secondary monitoring method. Specifically, the method disclosed in JP 2019-197146 A can be adopted.
Furthermore, still images acquired for primary and secondary monitoring may not be acquired from the video captured by each camera 1a, 1b, but a separate camera for still images may be provided and the primary and secondary monitoring may be performed using still images captured by the separate camera. However, if the cameras 1a, 1b for capturing video are also used for acquiring still images, the number of cameras can be reduced, which has a significant cost advantage.

In each embodiment, two cameras are used, but only one camera is acceptable, and three or more cameras may be used. Even when three or more cameras are used, a reference image is stored for each camera , and if the deviation of an image from any camera from the reference image exceeds a certain limit, the primary or secondary monitoring is determined to be abnormal. The video capture span setting is a common setting for each camera.
Also, the object of monitoring may be the fixed mold 92 rather than the movable mold 91. Furthermore, both the movable mold 91 and the fixed mold 92 may be monitored, and both of a pair of molds may be movable molds and each may be monitored.

As described above, the imaging start advance time T1 is a value greater than 0, but it may be set to 0. For example, it is set to 0 when the time required for the opening operation of the movable mold 91 is very short or when the opening operation of the movable mold 91 does not cause a primary monitoring abnormality. Since the total imaging time of the video is shortened, setting the imaging advance time to 0 has the advantage of requiring less storage capacity for saving the video.
Regarding the end of shooting, in the above embodiments, in the case of a secondary monitoring abnormality, the end of shooting is delayed by a time greater than 0, but a configuration in which no delay is imposed even in the case of a secondary monitoring abnormality may be adopted. Since the total shooting time of the video is shortened, the storage capacity for saving the video can be reduced as well.

In addition, in each of the above-mentioned embodiments, if an abnormality is detected during primary monitoring, video recording is stopped. However, there are cases where it is resumed after a temporary interruption (resuming as a video of the same lot). In other words, if an abnormality is detected during primary monitoring, the video of the molding device may be resumed after an operator checks and finds no problems, or it may be resumed after necessary measures are taken. In such cases, video recording is also resumed, and the timer is started again from zero, and secondary monitoring is performed when the ejection time Tp is reached. In such cases, the video file after resumption may be a different file from the video file before resumption, or they may be the same video file (using the recording pause function).

In the above embodiments, an injection molding apparatus using a thermoplastic resin as a material has been described as an example of the molding apparatus 9, but the use of the mold monitoring device of the present invention is not limited to this. The mold monitoring device of the present invention can be used to monitor molds in various molding apparatuses, such as injection molding apparatuses using other materials, molding apparatuses performing press molding, and molding apparatuses performing forging and casting.
Furthermore, although the device main body 2 is a portable computer device similar to a tablet PC, it may be a computer device similar to a desktop PC. Furthermore, it may be a computer device mounted in the main control unit 90 of the molding device 9. However, if the device main body 2 is portable, it is preferable because the worker can watch the video wherever he or she is in the factory.

Reference Signs List 1 Camera 2 Apparatus main body 21 Processor 22 Display 23 Input/output interface 3 Storage unit 31 Monitoring sequence program 32 Video file 331 Primary monitoring program 332 Secondary monitoring program 36 Setting information input program 9 Molding apparatus 90 Main control unit 91 Movable mold 92 Fixed mold

Claims (7)

A molding apparatus in which a set of molds, at least one of which is a movable mold, is closed to mold an article within the molds and then the molds are opened to remove the article, comprising: a mold monitoring device for monitoring the inside of the molds that are opened after molding,
a camera directed toward the inside of the open mold and capable of taking video;
A control unit that controls start and stop of video capture by the camera;
A judgment unit is provided for judging whether a molding state is normal or abnormal based on an image of the inside of the mold captured by the camera or another camera,
a video shooting span setting unit is provided which sets a timing for starting and ending video shooting by the camera in one molding operation, and the control unit controls the start and end of shooting by the camera in accordance with the setting in the video shooting span setting unit;
A mold monitoring device characterized in that the setting in the video capture span setting unit is set to a time width greater than zero based on the timing at which the judgment unit judges whether the molding state is normal or abnormal. The timing at which the judgment unit judges whether the molding state is normal or abnormal is the timing of primary monitoring after the mold is opened and before an article removal operation is performed,
The mold monitoring device according to claim 1, characterized in that the timing at which shooting begins in the video shooting span setting unit is prior to the timing of primary monitoring and is the timing at or before the start of the mold opening operation. The timing at which the determination unit determines whether the molding state is normal or abnormal is the timing of secondary monitoring that is performed after the article pick-up operation,
A mold monitoring device as described in claim 1 or 2, characterized in that the timing of starting shooting in the video shooting span setting unit is the timing at which the item removal operation begins or earlier, and the timing of ending shooting is the timing of secondary monitoring or later. The mold monitoring device according to claim 3, characterized in that the timing for ending the image capture is set so that if the secondary monitoring judges that the condition is normal, the image capture ends at that point, and if the secondary monitoring judges that the condition is abnormal, the image capture is extended by a predetermined time period. the determination unit performs secondary monitoring again after determining that an abnormality has occurred at the timing of the first secondary monitoring after the item pick-up operation,
The mold monitoring device according to claim 4, characterized in that the timing for ending recording in the video recording span setting unit is set so that recording ends at that point if the second or subsequent secondary monitoring is judged to be normal, and is set so that recording is extended by a predetermined time width if the secondary monitoring is judged to be abnormal. The mold monitoring device according to any one of claims 1 to 5, characterized in that the camera photographs the inside of the mold, which is a movable mold, and is installed so that both the start position and the end position of the movement of the movable mold when the mold is opened are included in the photographing area. A plurality of cameras are provided so that a plurality of locations inside the mold can be photographed simultaneously,
7. The mold monitoring device according to claim 1, wherein the timings for starting and ending the image capture in said video image capture span setting unit are set as common timings for each camera.

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