JP7621171B2 - Mold monitoring device and mold monitoring method - Google Patents

Description

The invention of this application relates to a mold monitoring device and a mold monitoring method for monitoring 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 to check whether the mold opens after molding and the item is properly removed, mainly for the purpose of performing the next molding. 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 various molding machines in which mold monitoring devices are used, the molds tend to become larger. The reason for the increase in mold size may be the increase in the size of the articles to be molded, but it may also be due to the desire to increase productivity by increasing the number of articles to be molded at one time.
Conventional mold monitoring devices used one camera for monitoring, but as molds become larger, it has become necessary to use multiple cameras. When the mold becomes larger, one camera may be sufficient if a wide-angle camera is used with a long shooting distance. However, the image quality may deteriorate and affect the monitoring work. Therefore, it is preferable to adopt a configuration in which the inside of the mold is divided into multiple areas and a camera is installed for each area to take pictures.

When using multiple cameras as described above, in addition to taking pictures of each area separately, other imaging methods may be required. For example, one camera may be required to take pictures of the entire inside of the mold, and another camera may be required to take pictures of only a specific area that requires special monitoring.
The present invention has been made in consideration of the above circumstances, and has an object to provide a practical mold monitoring device and mold monitoring method that can accommodate larger molds.

In order to solve the above problems, the mold monitoring device of the invention 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 kept closed while an article is molded inside the molds and then the molds are opened to remove the article.
This mold monitoring device is equipped with four or more cameras facing the inside of an open mold, and a judgment unit that judges whether the molding state is normal or abnormal based on the images of the inside of the mold taken by the cameras. Each camera is attached to take an image of an individual area obtained by dividing the inside of the mold into four or more areas, and the judgment unit compares the images sent from each camera with a reference image set for each area to judge whether the molding state is normal or abnormal.
In addition, in order to solve the above problem, the mold monitoring device can be configured so that at least one of the four cameras is installed so as to photograph areas inside the mold that are hidden from view by the other cameras and cannot be captured.

In addition, in order to solve the above-mentioned problems, a mold monitoring device according to another invention disclosed in this specification is a mold monitoring device that monitors the inside of the molds that have been opened after molding in a molding apparatus in which a set of molds, at least one of which is a movable mold, is kept closed while an article is molded inside the molds and then the molds are opened to remove the article.
This mold monitoring device includes a plurality of cameras capable of photographing the inside of an open mold, a judgment unit for judging whether a molding state is normal or abnormal based on the images of the inside of the mold photographed by the cameras, a storage unit, and a mode setting unit for setting an acquisition mode for the images photographed by each camera. The mode setting unit is a setting unit for setting a type regarding the nature of the image to be photographed in addition to a type regarding whether the image to be photographed is an image for judging whether a molding state is normal or abnormal , and is a setting unit capable of setting different types for each camera .
In order to solve the above problem, in this mold monitoring device, the type of the image captured may be either a still image or a video image.
In addition, in order to solve the above problems, in this mold monitoring device, the type of the image captured can be either an image captured using visible light, or a thermographic image that can obtain the temperature state by capturing an image using infrared light.

In addition, in order to solve the above-mentioned problems, a mold monitoring method according to another invention disclosed in this specification is a method for monitoring the inside of a mold that has been opened after molding in a molding apparatus in which a set of molds, at least one of which is a movable mold, is kept closed while an article is molded inside the molds and then the molds are opened to remove the article.
This mold monitoring method includes a photographing step of photographing the inside of the mold in an open state with a camera, and a judgment step of judging whether the molding state is normal or abnormal based on the image photographed by at least one camera in the photographing step.
The photographing step is a step in which two cameras photograph a common area inside the mold in an overlapping manner, and the two cameras photograph images having different characteristics from each other.
In order to solve the above problem, in this mold monitoring method, the photographing step may be a step of having one of the two cameras photograph a still image and the other photograph a video image.
In addition, in order to solve the above problem, in this mold monitoring method, the photographing step may be a step in which one of the two cameras is made to photograph using visible light, and the other is made to photograph using infrared light, thereby performing thermographic photography that can obtain the temperature state .

As described below, the mold monitoring device according to the disclosed invention uses four or more cameras, and each camera monitors the inner area of the mold, which is divided into four or more individual areas, so that a sufficiently fine monitoring image can be obtained even for a larger mold. Therefore, the device can be suitably used for monitoring the molds of molding machines, which are becoming larger.
In addition, a configuration in which at least one of the four or more cameras is installed to photograph a portion that is hidden from the other cameras and cannot be captured is suitable for molding an article with a complex structure or when the inner surface of the mold has a complex shape. In particular, since four or more cameras are used, it is possible to photograph the inside of the mold from diagonal directions above, below, left, and right, and it is possible to photograph all exposed portions inside the mold unless the structure is extremely complicated.
According to another disclosed invention, the mold monitoring device can set the image acquisition mode for each camera and can acquire images according to the purpose of the camera's installation, so the acquired images can be used for each monitoring according to the settings in the mode setting section, or can be saved in the memory section for reference. This expands the scope of use of multiple cameras and allows for optimization of their use.
Furthermore, according to a mold monitoring method of yet another disclosed invention, two cameras capture overlapping images of a common area inside the mold (take superimposed images), and since the nature of the images captured by the two cameras are different from each other, monitoring can be optimized according to the contents of the mold and molding process.

1 is a schematic diagram of a mold monitoring device according to an embodiment; FIG. 2 is a schematic perspective view showing a first example of the installation positions of the cameras. FIG. 11 is a schematic perspective view showing a second example of the installation positions of the cameras. FIG. 11 is a schematic diagram showing an example of a mode setting screen. 4 is a schematic diagram showing an example of a folder structure provided in a storage unit for storing image files; FIG. FIG. 4 is a schematic diagram showing a monitoring sequence program of a first example. FIG. 11 is a schematic diagram showing a monitoring sequence program of a second example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. FIG 1 is a schematic diagram of a mold monitoring device according to the present embodiment.
The mold monitoring device shown in Fig. 1 includes a plurality of cameras 11 to 14 and a device main body 2 to which the cameras 11 to 14 are connected. The molding device 9 includes a movable mold 91, a fixed mold 92, a moving mechanism 93 for moving the movable mold 91, a material injection system 94 for injecting material into the closed molds 91 and 92, a main control unit 90 for controlling each part, etc. In addition, although not shown, the device includes an ejection mechanism for performing an ejection operation for removing an article after molding, etc.

In this embodiment, up to four cameras can be connected to the device body 2 to capture images. Figures 2 and 3 are schematic perspective views showing examples of the installation positions of the cameras. Of these, Figure 2 is a schematic perspective view showing a first example of the installation positions, and Figure 3 is a schematic perspective view showing a second example of the installation positions. Figures 2 and 3 show a state immediately after the molds 91 and 92 are opened, and show a state in which the molded article P is held on the movable mold 91.
The first example shown in Fig. 2 is an installation example in which four cameras 11 to 14 are used. The second example shown in Fig. 3 is an installation example in which three cameras 11 to 13 are used. In either installation example, each of the cameras 11 to 14 is attached to a fixed mold 92.

First, an example of installation when using four cameras 11-14 will be described. In FIG. 2, the four cameras 11-14 are mounted so as to capture images of each of the areas (hereinafter referred to as individual areas) obtained by dividing the area inside the molds 91, 92 into areas equal to the number of cameras. In this example, the inside of the molds 91, 92 is generally rectangular, and is divided into four individual areas by dividing it into top, bottom, left and right. The installation position and orientation of each camera are adjusted so as to capture each individual area.

Each of the cameras 11-14 is directed toward the movable mold 91 and captures an image of the inner surface of the movable mold 91. Immediately after molding is completed and the molds 91, 92 are opened, the article P is held by the movable mold 91. Therefore, each of the cameras 11-14 also captures an image of the exposed surface of the molded article P. The "exposed surface" is the surface that is not in contact with the inner surface of the movable mold 91.
2, in this example, the two cameras 11, 12 on the left side are mounted so as to capture areas that are hidden and cannot be captured when viewed from the two cameras 13, 14 on the right side. Conversely, the two cameras 13, 14 on the right side are mounted so as to capture areas that are hidden and cannot be captured when viewed from the two cameras 11, 12 on the left side. The "areas that are hidden and cannot be captured" may be a specific area on the exposed surface of the article P, or a specific area on the inner surface of the movable mold 91.

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, and the like. Specifically, for example, a tablet PC equipped with a display of about 10 to 12 inches can be used as the device body 2. Each of the cameras 11 to 14 is connected to the input/output interface 23 of the device body 2 by a dedicated cable. The input/output interface 23 has ports (four ports) to which each of the cameras 11 to 14 is connected, and each of the cameras 11 to 14 is connected to each port.
Incidentally, each of the cameras 11 to 14 may be connected to the device body 2 via wireless communication such as NFC.

The device body 2 includes a mode setting section for setting the acquisition mode of the images sent from each of the cameras 11 to 14, a determination section for determining whether the molding state is normal or abnormal based on the acquired images, and the like.
The device body 2 also has a storage unit 3 such as an SSD or HDD. The storage unit 3 stores a setting information file 35 that records the acquisition modes set for the cameras 11 to 14, a monitoring sequence program 31 that controls the entire sequence of mold monitoring, each monitoring program 331, 332 that performs primary monitoring and secondary monitoring based on the monitored and acquired images, each reference image file 32 that each monitoring program 331, 332 refers to, and the like. Therefore, in this embodiment, the mode setting unit is composed of the storage unit 3 and the setting information file 35 stored in the storage unit 3. The judgment unit is composed of the device body 2 and each monitoring program 331, 332 implemented in the device body 2.

In addition to the above, the device body 2 also includes an image capture control program (not shown) that outputs control signals to the cameras 11-14 to capture still images and start and end video capture. The image capture control program is called and executed by the monitoring sequence program 31. In addition to the storage unit 3, the device body 2 also includes a memory (not shown) that temporarily stores image data of still images, etc.

The display 22 also functions as a touch panel and serves as an input section for various setting information, and a setting information registration program 36 is implemented in the device main body 2. The setting information registration program 36 is a program that displays an input screen for various setting information on the display 22 and records the input setting information in a 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. The connection to the main control unit 90 may also be made via wireless communication such as NFC.

Next, the acquisition mode for acquiring images from each of the cameras 11 to 14 will be described.
The acquisition mode indicates what type of images are to be acquired from each of the cameras 11 to 14, and is set in advance and recorded in the setting information file 35. Fig. 4 is a schematic diagram showing an example of a mode setting screen displayed on the display by a mode setting module, which is an element of the setting program.

In this embodiment, four acquisition modes can be set: still image monitoring mode, video monitoring mode, video reference mode, and thermography mode. The still image monitoring mode is a mode in which still images are acquired from the camera for primary and secondary monitoring. The video monitoring mode is a mode in which a video is captured by the camera and images (still images) from the captured video are used for primary and secondary monitoring. The video reference mode is a mode in which a video is captured by the camera but is not used for primary or secondary monitoring but is used for reference. The thermography mode is an acquisition mode that is set when the camera is a thermography camera.

4, in this embodiment, the mode setting screen is provided with acquisition mode input fields 41 to 44 for each of the four cameras 11 to 14. In this example, the acquisition mode input fields 41 to 44 are radio buttons for selecting one of the modes, but they may be in other formats such as a pull-down list.
The setting information registration program 36 includes a mode record module that records the values entered in the acquisition mode input fields 41 to 44 in the setting information file 35. When an OK button 45 provided on the mode setting screen shown in FIG. 4 is pressed, the mode record module is executed and the mode information is recorded in the setting information file 35.

FIG. 5 is a schematic diagram showing an example of a folder structure provided in the storage unit for storing image files.
The storage unit 3 is provided with a data storage folder 30, under which (as subordinate directories) are provided folders 51, 61, 71, 81 for storing image files 34 from the cameras 11 to 14 (hereinafter referred to as camera data folders). In this example, under the camera data folders 51, 61, 71, 81, still image folders 52, 62, 72, 82, video folders 53, 63, 73, 83, and thermography folders 54, 64, 74, 84 are provided. Under the still image folders 52 , 62, 72, 82, primary monitoring folders 521, 621, 721, 821 and secondary monitoring folders 522, 622, 722, 822 are further provided.

In this embodiment, the image files (still images or video) 34 of the images captured by each of the cameras 11 to 14 are files with the time of capture as the file name. It is possible to identify which camera the image file is from by the identification number set for each of the cameras 11 to 14 or the port number in the input/output interface 23. For example, the monitoring sequence program 31 stores a still image from the first camera 11 during primary monitoring in the primary monitoring folder 521 under the camera data folder 51 for the first camera 11 as necessary, and stores a still image from secondary monitoring in the secondary monitoring folder 522 as necessary. Also, if it is a video, it is stored in the video folder 53 under the camera data folder 51 for the first camera 11 as necessary, and if the first camera 11 is a thermography camera, the image file 34 is stored in the thermography folder 54 under the camera data folder 51 for the first camera 11 as necessary. The same applies to the second to fourth cameras 12 to 14.

The monitoring sequence program 31 is a program for carrying out a sequence corresponding to the acquisition mode thus set for each of the cameras 11 to 14. This point will be described below.
First, an example of the monitoring sequence program 31 when all four cameras 11 to 14 are in the still image monitoring mode will be described. Hereinafter, this example will be referred to as the first example. Fig. 6 is a schematic diagram showing the monitoring sequence program of the first example.

The monitoring sequence program 31 is always in an executed state while the molding device 9 is in operation, and in a standby state, it waits for the input of an operating status signal from the molding device 9. The monitoring sequence program 31 is given a constant time from when molding is started to when the primary monitoring occurs. This time includes the time from when the set of molds 91, 92 are closed to when the molds 91, 92 are opened, that is, the time from when the molds 91, 92 are closed, the material is injected, and until solidification is completed, and is a little longer than that. Hereinafter, this time will be referred to as the molding time.

When the monitoring sequence program 31 receives a signal indicating that the molds 91, 92 are closed at a certain time (hereinafter referred to as the molding start signal), it starts the timer count. Then, when the timer count reaches the molding time, it stops the timer count and resets it to zero. Then, the photography control program causes each of the cameras 11-14 to take a still image at that time, and each still image is acquired. Then, primary monitoring is performed for each of the cameras 11-14.

That is, the monitoring sequence program 31 acquires a reference image for primary monitoring for the first camera 11 from the memory unit 3, passes it as an argument to the primary monitoring program 331 along with the still image acquired from the first camera 11, and executes the primary monitoring program 331. The primary monitoring program 331 determines whether the difference between the acquired still image and the reference image is within a specified range, and outputs a normal return value if it is within the specified range. If it exceeds the specified range, it outputs an abnormal return value. These return values are temporarily stored in variables.

Similarly, the reference image for the second camera 12 is obtained from the memory unit 3 and passed as an argument to the primary monitoring program 331 together with the still image obtained from the second camera 12 to execute the primary monitoring program 331, and the return value is stored in another variable. Primary monitoring processing is similarly performed on the still image from the third camera 13 and the still image from the fourth camera 14, and each return value of the primary monitoring program 331 is stored in a different variable.

Then, if any of the return values is abnormal, 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 specifying which camera's result was abnormal is also output.
When a primary monitoring abnormality is output, the operation of the molding device 9 is stopped, so the primary monitoring program 331 is also interrupted and returned to a standby state (a state waiting for a molding start signal). If the primary monitoring is normal (the return values for all four cameras are normal), the monitoring sequence program 31 restarts the timer count as shown in FIG.
If the execution result of the primary monitoring program 331 is abnormal, the image file 34 of the abnormal still image is saved in a primary monitoring folder under a camera data folder for the camera that captured the abnormal still image.

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 protruding operation. Hereinafter, this time will be referred to as the protruding time.
6, if the primary monitoring result is normal, the monitoring sequence program 31 restarts the timer. Then, when the timer count reaches the protruding time, the monitoring sequence program 31 causes each of the cameras 11 to 14 to take a still image at that time and acquires each still image. Then, secondary monitoring is performed for each of the cameras 11 to 14.

That is, the monitoring sequence program 31 acquires a reference image for secondary monitoring for the first camera 11 from the memory unit 3, passes it as an argument to the secondary monitoring program 332 together with the still image acquired from the first camera 11, and executes the secondary monitoring program 332. The return value is then temporarily stored in a variable. The return value of the secondary monitoring program 332 is also normal or abnormal. If the difference between the acquired still image and the reference image is within a specified range, a value indicating normal secondary monitoring is returned, and if it exceeds this range, a value indicating abnormal secondary monitoring is returned.

Similarly, the reference image for the second camera 12 is obtained from the memory unit 3 and passed as an argument to the secondary monitoring program 332 together with the still image obtained from the second camera 12 to execute the secondary monitoring program 332, and the return value is stored in another variable. Secondary monitoring is similarly processed for the still image from the third camera 13 and the still image from the fourth camera 14, and the return values of the secondary monitoring program 332 are each stored in a different variable.

If any of the return values is abnormal, the monitoring sequence program 31 outputs a secondary monitoring abnormality to the main control unit 90 of the forming device 9. At this time, information specifying which camera's result was abnormal is also output. In addition, the monitoring sequence program 31 saves an image file 34 of the still image for which the secondary monitoring abnormality occurred in a secondary monitoring folder under the camera data folder for that camera.
The timer count is stopped when the ejection time is reached and is reset to 0. Whether the secondary monitoring is normal or abnormal, the monitoring sequence program 31 goes into a standby state for the next molding start signal.

Next, an example of a monitoring sequence program in which two of the four cameras are in the still image monitoring mode and one is in the video reference mode will be described. Hereinafter, this example will be referred to as the second example. Figure 7 is a schematic diagram showing a monitoring sequence program 31 of the second example.
The installation positions of the cameras 11 to 14 in this configuration correspond to the example shown in Fig. 3. As an example, the first and second cameras 11 and 12 in Fig. 3 are in the still image monitoring mode, and the third camera 13 is in the video reference mode. For the fourth camera 14, "stop" is selected on the mode setting screen and recorded in the setting information file 35.
3, the first camera 11 is installed so as to photograph the left half area of the movable mold 91, and the second camera 12 is installed so as to photograph the right half area of the movable mold 91. The third camera is installed so as to photograph a video of the entire movable mold 91. That is, the direction and zoom are adjusted so that the movable mold 91 in the closed position and the movable mold 92 in the open position are within the field of view.

In this embodiment, one video is taken for one molding cycle (i.e., one video file is generated). Therefore, in one molding cycle, the monitoring sequence program 31 transmits a control signal to start video recording and a control signal to end video recording to the third camera 13. At this time, in order to make video reference more effective and to prevent the capacity for storing videos from becoming excessive, the timing for starting and ending video recording is set based on the monitoring timing (the timing for determining whether the molding status is normal or abnormal).

In this embodiment, video recording starts a predetermined time before the primary monitoring timing, and ends a predetermined time after the secondary monitoring timing. Hereinafter, the time interval that precedes the primary monitoring timing is referred to as the advance time, and the time interval that is delayed from the secondary monitoring timing is referred to as the delay time.

7, in this example as well, when the molding start signal is received, the monitoring sequence program 31 starts counting the timer. Then, when the value reaches the value of (molding time-advance time), a video capture start signal is sent to the third camera 13.
After that, when the timer count reaches the molding time, the timer count is stopped and reset to zero. Then, as in the above example, a control signal for still image capture is sent to each of the first and second cameras 11 and 12. Then, a reference image for primary monitoring for the first camera 11 is acquired from the storage unit 3, and passed as an argument to the primary monitoring program 331 together with the still image acquired from the first camera 11 to execute the primary monitoring program 331, and the return value is stored in a variable. Also, a reference image for the second camera 12 is acquired from the storage unit 3, and passed as an argument to the primary monitoring program 331 together with the still image acquired from the second camera 12 to execute the primary monitoring program 331, and the return value is stored in another variable.

If any of the return values is abnormal, the monitoring sequence program 31 outputs a primary monitoring abnormality to the main control unit 90 of the molding device 9. It also saves an image file 34 of a still image taken by the abnormal camera in a primary monitoring folder under the camera data folder for that camera. It then returns to a standby state for a new molding start signal.

If both return values are normal, the monitoring sequence program 31 restarts the timer count. Then, when the timer count reaches the protrusion time, a control signal for still image capture is sent to each of the first and second cameras 11, 12 to perform secondary monitoring. That is, a reference image for secondary monitoring for the first camera 11 is obtained from the storage unit 3, and passed as an argument to the secondary monitoring program 332 together with the still image obtained from the first camera 11, the secondary monitoring program 332 is executed, and the return value is stored in a variable. Also, a reference image for secondary monitoring for the second camera 12 is obtained from the storage unit 3, and passed as an argument to the secondary monitoring program 332 together with the still image obtained from the second camera 12, the secondary monitoring program 332 is executed, and the return value is stored in a variable.

If any of the return values is abnormal, the monitoring sequence program 31 outputs a secondary monitoring abnormality to the main control unit 90 of the molding device 9. In addition, the image file 34 of the still image taken by the abnormal camera is saved in a secondary monitoring folder under the camera data folder for that camera.

Thereafter, when the timer count reaches the ejection time plus the delay time, the monitoring sequence program 31 stops the timer count and resets it to zero, and transmits a control signal to end video capture to the third camera 13. Then, it waits for a new molding start signal. At this time, if the result of the primary monitoring is abnormal or the result of the secondary monitoring is abnormal in the molding cycle, the monitoring sequence program 31 saves the image file 34 of the captured video in the video folder 73 under the camera data folder 71 for the third camera 13.

In the monitoring sequence program 31 of the second example above, if the primary monitoring results in an abnormality, a control signal to end the recording may be output to the third camera 13 at that point, and recording may be terminated. As for the secondary monitoring, the video recording may be terminated when the abnormality is detected, but it may be better to continue with a specified delay time. For example, the ejection operation of the molded article may not go well, and the article may be caught in the mold at the time of secondary monitoring, but may then fall naturally shortly thereafter, resulting in an irregular movement. In this case, when the worker goes to the mold, the article is found to be ejected normally, and the cause of the secondary monitoring abnormality is unclear. It is preferable to continue video recording, as such irregular movements can be confirmed in the video.

The following describes the overall operation of the mold monitoring device of this embodiment and the overall operation of the molding device 9. In the following description, an example is taken in which the cameras 11 to 14 are installed as shown in Figure 2 and all of the cameras 11 to 14 are in the still image monitoring mode.
In a manufacturing line for an article in which molding is performed using the molding device 9, an operator sets up the mold monitoring device. That is, each camera 11-14 is installed at a necessary location relative to the molds 91, 92 to be monitored, and is directed in a desired direction. Then, the zoom state (magnification) and other settings are performed on each camera 11-14. Then, after each camera 11-14 is connected to the device main body 2 with a dedicated cable, setting information for each camera 11-14 is input. That is, a mode setting screen is displayed on the display, the still image monitoring mode is selected for all cameras 11-14, the OK button 45 is pressed, and the setting information is recorded in the setting information file 35. In addition, the molding time and ejection time are also set. Then, the mold monitoring device is operated, and molding is performed by the molding device 9.

The molding device 9 injects material into the molds 91, 92 with the set of molds 91, 92 closed. At this time, a molding start signal is sent to the mold monitoring device. Upon receiving the molding start signal, the monitoring sequence program 31 executed on the device main body 2 starts counting on a timer.
The molding device 9 moves the movable mold 91 and opens the molds 91 and 92 until the set molding time is reached. Then, when the molding time is reached, the monitoring sequence program 31 sends a control signal to each of the cameras 11 to 14 to capture a still image at that time, and the primary monitoring program 331 is executed.

If the primary monitoring result is determined to be abnormal for any of the still images from the cameras, a primary monitoring abnormality is sent from the device body 2 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. This ejects the article and removes it from the molds 91, 92.

On the other hand, when the timer of the mold monitoring device reaches the molding time, it is reset to 0 and restarted. When the timer count reaches the ejection time, the mold monitoring device stops the timer count and resets it to 0, and performs secondary monitoring. When an abnormality is returned for the still image from any of the cameras, the monitoring sequence program 31 outputs a secondary monitoring abnormality to the main control unit 90 of the molding device 9.
The main control unit 90 of the molding device 9, which receives the output of the secondary monitoring abnormality, stops the next molding cycle and leaves the molds 91, 92 open. If the secondary monitoring is normal, the molding device 9 closes the molds 91, 92 again, injects material, and performs the next molding cycle. A molding start signal is input to the mold monitoring device, and the monitoring sequence program 31 starts counting the timer. Thereafter, the same process is repeated.

According to the embodiment of the mold monitoring device relating to the above operation, four cameras 11 to 14 are used, and the inner areas of the molds 91, 92, which are divided into four individual areas, are monitored by each camera 11 to 14, so that sufficiently fine monitoring images can be obtained even for larger molds. For this reason, it can be used more suitably for monitoring the molds of molding machines that are becoming larger.

At this time, at least one of the four cameras 11-14 is installed so as to capture areas that are hidden from the other cameras and cannot be captured, making this particularly suitable for molding objects with complex structures or when the inside of the mold has a complex shape. This point is closely related to the use of four cameras 11-14. In other words, using four cameras 11-14 makes it possible to capture images of the inside of the mold from diagonal directions above, below, left, and right, as shown in Figure 2, and unless the structure is extremely complex, it is possible to capture images of all exposed parts inside the mold. This effect is enhanced if five or more cameras are used, but with a minimum of four cameras, it is possible to handle almost all molds.

In addition, in the mold monitoring device of the embodiment, the image acquisition mode can be set for each camera 11 to 14, making it possible to acquire images according to the purpose for which the camera is installed. The acquired images can then be used for each monitoring operation according to the settings in the mode setting section, or can be stored in the memory section 3 for reference. This expands the range of use of multiple cameras, allowing for optimized usage.

Next, a supplementary explanation will be given of the embodiment of the invention of the mold monitoring method.
The mold monitoring method of the embodiment is a method in which two cameras overlap and capture images of a common area inside the mold. Therefore, as an example, in the mold monitoring device of the above-mentioned embodiment, when three cameras 11 to 13 are installed as shown in Fig. 3, the first camera 11 or the second camera 12 and the third camera 13 are set in the mode setting unit so as to capture images of different characteristics. For example, as described above, this is the case when the first and second cameras 11 and 12 are in the still image monitoring mode and the third camera 13 is in the video reference mode.
In addition to the above, the first and second cameras 11 and 12 may be in a video monitoring mode, and the third camera 13 may be in a still image monitoring mode. Furthermore, the first and second cameras 11 and 12 may be in a still image monitoring mode, and the third camera 13 may be in a thermography mode.

The mold monitoring method corresponds to the operation of the mold monitoring device described above, in which the monitoring sequence program 31 has the second example configuration. After the worker installs the first to third cameras 11-13 as shown in FIG. 3, on the mode setting screen, the worker selects the still image monitoring mode for the first and second cameras 11, 12, and the video reference mode for the third camera 13. For the fourth camera 14, the worker selects stop. Then, the worker presses the OK button 45 to record this setting information in the setting information file 35.

When a molding start signal is sent from the main control unit 90 of the molding device 9, the monitoring sequence program 31 starts a timer and causes the third camera 13 to start taking video at the timing of molding time - advance time. Then, when the molding time arrives, the monitoring sequence program 31 resets the timer to zero and sends a control signal to each of the first and second cameras 11, 12 to take still images, acquiring each still image, and executes the primary monitoring program 331. Then, if any of the return values indicates a primary monitoring abnormality, a primary monitoring abnormality is output to the main control unit of the molding device. At this time, the image file 34 of the abnormal still image is saved in the still image folder for that camera.

If the primary monitoring is normal, the monitoring sequence program 31 restarts the timer. Then, when the push-out time is reached, a control signal for taking still images is sent to the first and second cameras 11, 12 to acquire each still image, and the secondary monitoring program 332 is executed. If any of the return values indicates a secondary monitoring abnormality, a secondary monitoring abnormality is output to the main control unit 90 of the molding device 9. At this time, the image file 34 of the abnormal still image is saved in the still image folder for that camera.

Thereafter, when the timer count reaches the protrusion time plus the delay time, the monitoring sequence program 31 resets the timer to zero and outputs a control signal to the third camera to end shooting, causing the third camera 13 to end video shooting. If an abnormality is detected in the primary or secondary monitoring, the monitoring sequence program 31 saves an image file 34 of the video in the video folder 73 under the camera data folder 71 for the third camera 13.

According to this mold monitoring method, two cameras capture images of a common area inside the molds 91, 92 in an overlapping manner (taking images in a superimposed manner), and since the nature of the images captured by the two cameras are different from each other, monitoring can be optimized according to the mold and the contents of the molding process. That is, while primary and secondary monitoring can be performed by dividing the area and acquiring still images for each individual area, video monitoring can also be performed by recording the overall operating status of the molds 91, 92 as a video. For example, if an abnormality is found in the primary or secondary monitoring using still images, the circumstances under which the abnormality occurred can be analyzed by checking the situation at that time using a video.

In the above example, the area captured by still images is a limited area, and the area captured by video is a wider area that includes that area, but the reverse is also possible. For example, it is possible to use one camera to capture still images of the entire mold and use these for primary and secondary monitoring, while another camera captures video of only a specific, limited area and refers to that. It is also possible to divide the area into two, and use the first and second cameras to capture still images for primary and secondary monitoring, while using a third and fourth camera to capture video of specific locations within each individual area and refer to that video.

Furthermore, still images may be extracted from video image data for primary and secondary monitoring, and the still images may be used for reference. For example, a video may be taken of the entire area of the mold, and still images taken at the primary and secondary monitoring times may be used to determine normality and abnormality, while still images of a specific area at a specific time may be taken for reference. For example, if a zoomed-in still image of a specific location at a specific time is useful for analyzing the molding status, such capture may be performed superimposed on a camera other than the one used to capture the video.

As a further explanation of thermography, in the embodiment of the mold monitoring device described above, the thermography mode is a mode for taking thermography images for reference as a video. For example, if the first and second cameras 11 and 12 take still images of individual areas (still image monitoring mode) and the third camera 13 is in a video reference mode for taking a video of the entire mold, an infrared camera can be installed as the fourth camera 14, the thermography mode can be set, and a thermography video of the entire mold can be taken. The thermography video taken by the fourth camera 14 can be referred to as necessary to check the temperature state and temperature distribution of the mold.

Thermography may also be performed for the purpose of having the judgment unit judge whether the molding situation is normal or abnormal, and outputting the result to the main control unit 90 of the molding device 9. For example, if the temperature of the mold surface rises above a certain temperature, control may be performed to stop the molding device 9 as it is abnormal. In this case, a mold temperature monitoring program that judges whether the molding situation is normal or abnormal depending on the state of the mold surface temperature is implemented in the device main body 2. Then, for example, a configuration may be adopted in which the thermography camera takes a still thermography image at the timing of primary monitoring, and the mold temperature monitoring program analyzes this to judge whether it is normal or abnormal. For example, it may be judged from the thermography image whether a specific location is hotter than a limit, or whether the average temperature of the entire mold is hotter than a limit.

Furthermore, the insides of the molds 91, 92 may be illuminated and photographed by the cameras 11-14. In this case, the wavelength of the light used for illumination may be in the visible range, but as disclosed in JP-A-2007-21797 and JP-A-2003-305748, illumination may be performed with infrared light from the long wavelength side of the visible range, and photographing may be performed by the cameras 11-14 while avoiding external disturbances.

Even in these cases, according to the mold monitoring method of the embodiment, it is possible to perform overlapping photography of different natures, i.e., primary and secondary monitoring using still images in visible light, or to record video using visible light for reference, thereby optimizing mold monitoring by making more effective use of multiple cameras.

In the above embodiments, an injection molding device using thermoplastic resin as the material has been described as an example of the molding device 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 devices, such as injection molding devices that use other materials, molding devices that perform press molding, and molding devices that perform forging and casting.

Although the device main body 2 was 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 it allows workers to view still images and videos wherever they are in the factory.

Reference Signs List 11 to 14: Camera 2: Apparatus body 21: Processor 22: Display 23: Input/output interface 3: Memory section 31: Monitoring sequence program 32: Reference image file 331: Primary monitoring program 332: Secondary monitoring program 34: Image file 35: Setting information file 36: Setting information registration program 9: Molding apparatus 90: Main control section 91: Movable mold 92: Fixed mold

Claims (9)

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,
Four or more cameras pointed inside the open mold;
A judgment unit is provided to judge whether a molding state is normal or abnormal based on the images of the inside of the mold captured by each camera,
Each camera is attached so as to photograph an individual area obtained by dividing the inside area of the mold into areas equal to the number of cameras,
A mold monitoring device characterized in that the judgment unit compares the images sent from each camera with reference images set for each camera to judge whether the molding state is normal or abnormal. The mold monitoring device according to claim 1, characterized in that at least one of the four or more cameras is mounted to capture an area inside the mold that is hidden from the other cameras and cannot be captured. 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,
Multiple cameras capable of photographing the inside of an open mold,
a judgment unit for judging whether a molding state is normal or abnormal based on the image of the inside of the mold captured by the camera;
A storage unit;
and a mode setting unit that sets an acquisition mode for an image captured by each camera,
The mode setting unit is a setting unit that sets for each camera the type of image to be captured, whether the image is for determining whether the molding state is normal or abnormal, as well as the type of image to be captured , and is a setting unit that can set different types for each camera. This mold monitoring device is characterized in that it is a setting unit that sets for each camera the type of image to be captured. The mold monitoring device according to claim 3, characterized in that the type of the captured image is either a still image or a video image. A mold monitoring device as described in claim 3 or 4, characterized in that the type of the image to be captured is either an image captured using visible light or a thermographic image that can obtain the temperature state by capturing an image using infrared light. 1. A mold monitoring method for a molding apparatus in which a set of molds, at least one of which is a movable mold, is closed to mold an article inside the molds and then the molds are opened to remove the article, the method comprising:
A photographing step of photographing the inside of the open mold with a camera;
and a determination step of determining whether or not a molding state is normal or abnormal based on an image captured by at least one camera in the photographing step,
The mold monitoring method is characterized in that the photographing step is a step in which two cameras overlap and photograph a common area inside the mold, and the two cameras photograph images having different characteristics from each other. The mold monitoring method according to claim 6, characterized in that the photographing step is a step in which one of the two cameras is made to take a still image and the other is made to take a video. The mold monitoring method according to claim 6, characterized in that the photographing step is a step of having one of the two cameras photograph using visible light and the other photograph using infrared light to perform thermographic photography capable of obtaining the temperature state . 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 that can take pictures of the inside of an open mold,
A judgment unit is provided for judging whether a molding state is normal or abnormal based on the image of the inside of the mold captured by the camera,
The camera is a camera capable of capturing a thermographic image capable of acquiring a temperature state by capturing an image using infrared rays,
The mold monitoring device is characterized in that the judgment unit judges whether the molding state is normal or abnormal based on the temperature state inside the mold acquired by a thermographic image.

Images