JP7154173B2 - MONITORING DEVICE, MONITORING METHOD, AND MONITORING PROGRAM FOR MONITORING STRAND MANUFACTURER - Google Patents

Description

The present invention relates to a monitoring device, a monitoring method, and a monitoring program for monitoring strand manufacturing equipment that discharges a plurality of strands. In the present specification, claims, drawings, and abstract, the term "strand" refers to a string-like molded body.

Synthetic resin materials are generally marketed as pellets several millimeters in size. In many cases, the polymer raw material obtained by the polymerization reaction is in the form of powder, and in order to improve transportability and handleability, it is shipped through a pelletizing process of forming the powder into pellets. In addition, in the pelletization process, additives such as antioxidants, antistatic agents, and reinforcing agents can be mixed with the polymeric raw material to impart additional functions to the synthetic resin material. As described above, the pelletization process plays an important role in improving the commercial value of synthetic resin materials.

A strand cut method is widely used as a typical aspect of such a pelletizing process. In the pelletization process of the strand cut method, the thermoplastic resin material is heated to the melting point or higher in the extruder to melt and flow, and the melted resin material is continuously discharged from a die having a discharge port several millimeters in size. do. The discharged resin material becomes a strand and is continuously guided to a cooling device. The cooled strand is cut into several millimeters long by a shredding machine called a pelletizer. In this way, the pelletization process of the strand cut method is based on the premise that the strands discharged from the extruder are continuously guided to the pelletizer through the cooling device. requires that the strands be produced stably and continuously.

Typical anomalies that interfere with strand production include strand coalescence and strand breakage. Coalescence of strands is a phenomenon in which a plurality of strands having fluidity immediately after being ejected from a die adhere to each other and are coalesced. Further, strand breakage is a phenomenon in which a strand receives tension for some reason and is cut. The occurrence of these anomalies can lead to deterioration in the quality of pellets produced, reduction in productivity, and damage to equipment. Therefore, it is required to detect these abnormalities at an early stage and perform restoration work.

For example, Japanese Patent Application Laid-Open No. 2004-276439 (Patent Document 1) focuses on the fact that the cut strand hangs down below the die, and a sensor such as a phototube type sensor is provided at a position where the strand can hang down to cut the strand. Techniques for detecting are disclosed. In addition, in Japanese Patent Application Laid-Open No. 2000-289092 (Patent Document 2), a detection arm arranged at a position supported by a running strand is lowered by its own weight when the strand is cut. Disclosed is a technique for detecting the disconnection of These techniques enable early detection of strand breakage.

JP-A-2004-276439 JP-A-2000-289092

However, according to the techniques of Patent Literatures 1 and 2, it was possible to detect an abnormality in which the strands were cut at an early stage, but it was not possible to detect an abnormality in which the strands were united.

Therefore, it is desired to realize a monitoring device, a monitoring method, and a monitoring program that can detect both abnormalities in which strands are cut and abnormalities in which strands are united.

A first monitoring device according to the present invention is a monitoring device for monitoring a strand manufacturing machine that discharges a plurality of strands, the coordinates of a plurality of detection points arranged on a detection axis that intersects the strand discharge direction. and a set of measured temperatures, a current temperature information set that is the temperature information set at a certain moment, and the temperature information set in a state in which the strand is normally discharged. a calculation unit capable of determining whether or not an abnormality has occurred in the discharge state of the strand at that moment based on comparison with a certain reference set , wherein the calculation unit is configured to use the current temperature information set or the reference For the set, it is possible to identify a maximum value coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinate, and the number of the maximum value coordinates in the current temperature information set and the reference set. and the number of the maximum value coordinates of the current temperature information set is less than the number of the maximum value coordinates of the reference set, and at least the number of the maximum value coordinates of the current temperature information set at least two of the strands meet when the measured temperature at one of the local maximum coordinates is higher than the measured temperature at another of the local maximum coordinates of the current temperature information set by more than a predetermined criterion; It is characterized by judging that an abnormality of one mode has occurred .
A second monitoring device according to the present invention is a monitoring device for monitoring a strand manufacturing machine that discharges a plurality of strands, the coordinates of a plurality of detection points arranged on a detection axis that intersects the strand discharge direction. and a set of measured temperatures, a current temperature information set that is the temperature information set at a certain moment, and the temperature information set in a state in which the strand is normally discharged. a calculation unit capable of determining whether or not an abnormality has occurred in the discharge state of the strand at that moment based on comparison with a certain reference set, wherein the calculation unit is configured to use the current temperature information set or the reference For the set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value on a curve plotting the measured temperature against the coordinate, and the number of the maximum value coordinates in the current temperature information set is the reference set. and the measured temperatures at all the local maximum coordinates of the current temperature information set are values within a predetermined reference range, at least one of the strands is cut It is characterized in that it is determined that an abnormality in the form of
A third monitoring device according to the present invention is a monitoring device for monitoring a strand manufacturing machine that discharges a plurality of strands, the coordinates of a plurality of detection points arranged on a detection axis that intersects the strand discharge direction. and a set of measured temperatures, a current temperature information set that is the temperature information set at a certain moment, and the temperature information set in a state in which the strand is normally discharged. a calculation unit capable of determining whether or not an abnormality has occurred in the discharge state of the strand at that moment based on comparison with a certain reference set, wherein the calculation unit is configured to use the current temperature information set or the reference For the set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value on a curve plotting the measured temperature against the coordinate, and the number of the maximum value coordinates in the current temperature information set is the reference set. and the difference between the maximum value of the current temperature information set and a predetermined reference temperature is greater than a predetermined threshold, the strand characterized by determining that the temperature of is abnormal.
A fourth monitoring device according to the present invention is a monitoring device for monitoring a strand manufacturing machine that discharges a plurality of strands, the coordinates of a plurality of detection points arranged on a detection axis that intersects the strand discharge direction. and a set of measured temperatures, a current temperature information set that is the temperature information set at a certain moment, and the temperature information set in a state in which the strand is normally discharged. and a computing unit capable of determining whether or not there is an abnormality in the discharge state of the strand at that moment based on comparison with a certain reference set, and at least two of the detections spaced apart along the discharge direction. Based on a first current temperature information set acquired by a first detection axis located on the side closer to the strand manufacturing equipment, the presence or absence of an abnormality related to the temperature of the strand is determined, and the strand manufacturing It is characterized in that whether or not there is an abnormality related to the coalescence or cutting of the strands is determined based on a second set of current temperature information acquired in a second detection axis positioned farther from the device.

A first monitoring method according to the present invention is a monitoring method for monitoring a strand manufacturing machine that discharges a plurality of strands, wherein a plurality of strands arranged on a detection axis that intersects the strand discharge direction at a given moment. a current temperature information set, which is a set of coordinates and measured temperatures related to the detection points of the above ; identifying, for the current temperature information set and the reference set, identifying a maximum value coordinate at which the measured temperature takes a maximum value on a curve obtained by plotting the measured temperature against the coordinates; and the current temperature information. comparing the number of the local maximum coordinates in the set with the number of the local maximum coordinates in the reference set, and comparing the number of the local maximum coordinates in the current temperature information set with the number of the local maximum coordinates in the reference set; and the measured temperature at at least one of the local maximum coordinates of the current temperature information set exceeds a predetermined criterion compared to the measured temperatures at the other local maximum coordinates of the current temperature information set. and determining that an abnormality in which at least two of the strands are united occurs when the height is high .
A second monitoring method according to the present invention is a monitoring method for monitoring a strand manufacturing machine that discharges a plurality of strands, wherein a plurality of detection lines arranged on a detection axis intersecting the discharge direction of the strands at a given moment. A current temperature information set, which is a set of coordinates and measured temperatures for points, and a reference set, which is a set of coordinates and measured temperatures for the plurality of detection points in a state in which the strand is being discharged normally, are specified. identifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinates; The number of the maximum value coordinates is less than the number of the maximum value coordinates of the reference set, and the measured temperature at all the maximum value coordinates of the current temperature information set is within a predetermined reference range. and sometimes determining that at least one of the strands is abnormally cut.
A third monitoring method according to the present invention is a monitoring method for monitoring a strand manufacturing machine that dispenses a plurality of strands, wherein a plurality of detectors are arranged on a detection axis that intersects the direction of strand ejection at a given moment. A current temperature information set, which is a set of coordinates and measured temperatures for points, and a reference set, which is a set of coordinates and measured temperatures for the plurality of detection points in a state in which the strand is being discharged normally, are specified. identifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinates; The number of the local maximum value coordinates matches the number of the local maximum value coordinates of the reference set, and the difference between the local maximum value of the current temperature information set and a predetermined reference temperature is greater than a predetermined threshold. and determining that the temperature of the strand is abnormal when a local maximum coordinate exists.
A fourth monitoring method according to the present invention is a monitoring method for monitoring a strand manufacturing machine that discharges a plurality of strands, wherein a plurality of detection lines arranged on a detection axis intersecting the discharge direction of the strands at a given moment. At least a current temperature information set, which is a set of coordinates and measured temperatures for points, and a reference set, which is a set of coordinates and measured temperatures for the plurality of detection points in a state in which the strand is being discharged normally. Determining whether there is an abnormality related to the temperature of the strand based on the step of specifying the two detection axes and the first current temperature information set acquired in the first detection axis located on the side closer to the strand manufacturing equipment. and determining whether or not there is an abnormality related to coalescence or cutting of the strands based on a second current temperature information set acquired at a second detection axis located farther from the strand manufacturing equipment. It is characterized by

In addition, a first monitoring program according to the present invention is a monitoring program for monitoring a strand manufacturing machine that discharges a plurality of strands, and when executed in a computer, at a given moment, the direction of discharge of the strands intersects the direction of the strands. A current temperature information set, which is a set of coordinates and measured temperatures related to a plurality of detection points arranged on the detection axis, and a set of coordinates and measured temperatures related to the plurality of detection points in a state in which the strand is normally discharged. a reference set , which is a pair; and specifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve obtained by plotting the measured temperature against the coordinate. and the number of the local maximum value coordinates in the current temperature information set and the number of the local maximum value coordinates in the reference set, and the number of the local maximum value coordinates in the current temperature information set is compared with the less than the number of the local maximum coordinates of the reference set, and the measured temperature at at least one of the local maximum coordinates of the current temperature information set is less than the measured temperature at the other local maximum coordinates of the current temperature information set and a function of judging that an abnormality in which at least two of the strands are united has occurred when the difference is higher than a predetermined standard .
A second monitoring program according to the present invention is a monitoring program for monitoring a strand manufacturing machine that dispenses a plurality of strands, and when executed in a computer, detects crossing the strand ejection direction at a given moment. A current temperature information set, which is a set of coordinates and measured temperatures related to a plurality of detection points arranged on an axis, and a set of coordinates and measured temperatures related to the plurality of detection points in a state in which the strand is normally discharged. a function of identifying a reference set; and a function of identifying a maximum value coordinate at which the measured temperature takes a maximum value on a curve obtained by plotting the measured temperature against the coordinates for the current temperature information set and the reference set. and the number of the local maximum value coordinates in the current temperature information set is less than the number of the local maximum value coordinates in the reference set, and the measured temperature at all the local maximum value coordinates in the current temperature information set exceeds a predetermined and a function of judging that there is an abnormality in which at least one of the strands is cut when the value is within the reference range of the computer.
A third monitoring program according to the present invention is a monitoring program for monitoring a strand manufacturing machine that dispenses a plurality of strands, the monitoring program being executed by a computer to detect crossing the strand ejection direction at a given moment. A current temperature information set, which is a set of coordinates and measured temperatures related to a plurality of detection points arranged on an axis, and a set of coordinates and measured temperatures related to the plurality of detection points in a state in which the strand is normally discharged. a function of identifying a reference set; and a function of identifying a maximum value coordinate at which the measured temperature takes a maximum value on a curve obtained by plotting the measured temperature against the coordinates for the current temperature information set and the reference set. and the number of the local maximum value coordinates of the current temperature information set matches the number of the local maximum value coordinates of the reference set, and the relationship between the local maximum value of the current temperature information set and a predetermined reference temperature and a function of judging that the temperature of the strand is abnormal when there is the maximum value coordinate whose difference is larger than a predetermined threshold.
A fourth monitoring program according to the present invention is a monitoring program for monitoring a strand manufacturing machine that dispenses a plurality of strands, and which, when executed in a computer, detects at a certain instant that the strands are intersecting the direction in which the strands are ejected. A current temperature information set, which is a set of coordinates and measured temperatures related to a plurality of detection points arranged on an axis, and a set of coordinates and measured temperatures related to the plurality of detection points in a state in which the strand is normally discharged. a reference set for at least two of said sensing axes; and a first set of current temperature information obtained at a first sensing axis located closer to said strand manufacturing equipment. and based on the second current temperature information set acquired in the second detection axis located on the far side from the strand manufacturing equipment, the presence or absence of an abnormality related to the coalescence or cutting of the strands and a function of judging is realized by the computer.

According to these configurations, it is determined whether or not there is an abnormality in the discharge state of the strand based on the temperature of the strand itself discharged from the strand manufacturing apparatus, so it is possible to detect both abnormalities in cutting and coalescence. .
According to the first monitoring device, monitoring method, and monitoring program, since the number of strands is clarified based on the number of coordinates of maximum value, it is easier to discover strand coalescence and breakage, especially strand coalescence. Accurate detection of anomalies is easy.
According to the second monitoring device, monitoring method, and monitoring program, since the number of strands is clarified based on the number of coordinates of maximum value, it is easier to detect strand coalescence and breakage. can be detected accurately.
According to the third monitoring device, monitoring method, and monitoring program, since the number of strands is clarified based on the number of coordinates of maximum value, it is easier to discover strand coalescence and breakage, and furthermore, the temperature of strands can be measured. Anomalies can be detected.
According to the fourth monitoring device, monitoring method, and monitoring program, it is possible to determine the presence or absence of temperature abnormality based on the temperature of the strand immediately after discharge, so it is easy to accurately determine the temperature of the strand. In addition, since the presence or absence of coalescence and cutting is determined based on the temperature at the position closest to the most downstream of the region where strand coalescence and cutting can occur, it is easy to accurately determine the discharge state of the strands.

Preferred embodiments of the present invention are described below. However, the scope of the present invention is not limited by the preferred embodiments described below.

As one aspect of the monitoring device according to the present invention, it is preferable that the reference set is the latest current temperature information set determined that the ejection state is normal.

According to this configuration, the presence or absence of an abnormality can be determined based on the latest normal state, so even if there is a minor change in production conditions, there is little need to change the setting of the monitoring device.

As one aspect of the monitoring device according to the present invention, the calculation unit may be configured such that, for the current temperature information set or the reference set, the measured temperature is a maximum value on a curve obtained by plotting the measured temperature with respect to the coordinates. It is possible to specify the value coordinates, and whether or not there is an abnormality in the ejection state based on a comparison between the number of the maximum value coordinates in the current temperature information set and the number of the maximum value coordinates in the reference set. can be determined.

According to this configuration, since the number of strands is clarified based on the number of maximum value coordinates, it is easier to discover strand coalescence and strand breakage.

As one aspect of the monitoring device according to the present invention, the calculation unit may use the arrangement of the local maximum value coordinates of the current temperature information set as a further criterion for determining whether or not there is an abnormality in the ejection state. preferable.

According to this configuration, it is easy to distinguish and detect coalescence, in which the arrangement of strands is likely to change, and cutting, in which the arrangement of normal strands is difficult to change.

As one aspect of the monitoring device according to the present invention, the computing unit, for the current temperature information set or the reference set, calculates a filter value, which is a minimum value of temperature treated as valid data, as a maximum value and a minimum value on the curve. can be set by selecting from values between It is preferable to use it as a further judgment material for whether or not there is an abnormality in the

According to this configuration, it is easy to distinguish and detect a coalescence in which both the number of local maximum coordinates and the peak width are likely to change, and a truncation in which the number of local maximum coordinates changes but the peak width does not easily change.

Further features and advantages of the invention will become clearer from the following description of exemplary and non-limiting embodiments described with reference to the drawings.

Schematic diagram of the pelletizing device according to the present embodiment Schematic plan view of the vicinity of the die of the pelletizing apparatus according to the present embodiment Example plot of temperature information set with normal strands Schematic plan view when strand coalescence occurs An example plot of the temperature information set when strand coalescence occurs Schematic plan view when strand breakage occurs An example plot of a temperature information set when a strand break occurs Schematic plan view of overlapping strands An example plot of a temperature information set with overlapping strands A diagram showing a judgment flow according to the present embodiment.

Embodiments of a monitoring device, a monitoring method, and a monitoring program according to the present invention will be described with reference to the drawings. Hereinafter, an example in which the monitoring device according to the present invention is applied to a monitoring device 1 that monitors an extruder E (example of strand manufacturing equipment) included in a pelletizing device P that pelletizes a resin material will be described.

[Overview of monitored objects]
As a premise for explaining the monitoring device 1 according to the present embodiment, an outline of the pelletizing device P will be explained (FIG. 1). The pelletizing device P includes an extruder E, a cooling water tank B, and a pelletizer C. The extruder E heats the thermoplastic resin material to a melting point or higher to make it melt and flow, and continuously discharges it from a die D having a discharge port several millimeters in size. The resin material discharged from the die becomes a strand S, which is continuously taken up by a pelletizer C, passes through water in a cooling water tank B, and reaches the pelletizer C after being cooled below its melting point. The pelletizer C cuts the strand S into lengths of several millimeters to produce pellets several millimeters in size.

In this embodiment, an example in which the die D has seven ejection openings will be described (FIG. 2). The strands S (S ₁ to S ₇ ) discharged from the seven discharge ports are guided by a guide Bs arranged in the water stored in the cooling water tank B and enter the water.

A resin material to be pelletized using the pelletizing device P is a thermoplastic resin such as polyethylene or polypropylene. In pelletizing, it is necessary to heat to a temperature sufficiently higher than the melting point of the resin material to be pelletized in order to ensure sufficient fluidity to discharge the strands S. Therefore, the set temperature of the die D is, for example, about 180° C. for polyethylene pelletization and about 200° C. for polypropylene pelletization. Also, even in the case of materials other than the resin materials exemplified above, the set temperature of the die D is typically about 100 to 400° C., which is much higher than room temperature. Therefore, the temperature of the strand S immediately after being ejected from the die D is also sufficiently higher than room temperature.

In the production of pellets by the pelletizing device P, anomalies can occur in which the strands S coalesce with each other. The strand S immediately after being discharged from the die D is at a temperature above the melting point and has a certain degree of fluidity. Therefore, when the strands S adjacent to each other come into contact with each other, they stick to each other and merge. Since the plurality of strands S enter the water of the cooling water tank B in a united state, they are cooled in the united state and do not separate from each other. Finally, since the plurality of strands S are cut together while being united by the pelletizer C, pellets having a cross-sectional area corresponding to a plurality of strands are obtained. Such pellets can be rejected because they are larger than originally intended. Moreover, since a strand having a cross-sectional area larger than that normally assumed is introduced into the pelletizer C, there is a risk that the blade portion of the pelletizer C may be damaged.

Moreover, in the production of pellets by the pelletizing apparatus P, an abnormality such as the strand S being cut may occur. When the strand S is subjected to tension for some reason, the strand S is cut when the applied tension exceeds the tensile strength of the strand S in its molten state. When the strand S is cut, the strand S is deposited under the die D without being guided by the pelletizer C, and thus does not contribute to the production of pellets.

In order to continue stable production of pellets, it is necessary to detect such abnormalities at an early stage and carry out restoration work. The monitoring device 1 according to this embodiment quickly detects these abnormalities and notifies the operator of the necessity of restoration work.

[Configuration of monitoring device]
A monitoring device 1 includes a thermo camera 2 and a computer 3 (an example of a computing unit) (FIG. 1). The thermo camera 2 and the computer 3 are communicably connected, and the extruder E is monitored by the computer 3 arithmetically processing data relating to the image captured by the thermo camera 2 .

As used herein, the term "thermo camera" refers to a device that visualizes the surface temperature distribution of an object to be inspected. For example, devices that detect infrared rays emitted from the surface of an object and visualize the surface temperature distribution of the object based on the intensity of the infrared rays are generally distributed. The thermo camera 2 in this embodiment is a well-known thermo camera that is generally distributed.

The thermo camera 2 according to the present embodiment photographs the strand S discharged from the die D from above the die D and the cooling water tank B. As shown in FIG. Specifically, the thermo camera 2 can photograph at least the range indicated by the dashed line 21 in FIG.

In the following description, the parts denoted by reference numerals 21, 22 and 23 in FIG. 2 are referred to as "shooting range 21", "first detection axis 22" and "second detection axis 23", respectively. The first detection axis 22 and the second detection axis 23 are parallel to the horizontal direction of the imaging range 21 and intersect the discharge direction of the strands S.

[Monitoring method]
The photographing data (original data) generated by the thermo camera 2 consists of three values of [horizontal coordinate, vertical coordinate, measured temperature] for each division of the photographing range 21 equally spaced in the vertical and horizontal directions. It is organized as a group of tuples. The computer 3 receives the photographed data of the photographing range 21 from the thermo camera 2 .

First, a description will be given of the state of the strand S, the generated imaging data, and the result of the arithmetic processing when the discharge state of the strand S is normal. In addition, when the discharge state of the strand S is normal, the strands S ₁ to S ₇ discharged from the die D are guided to the cooling water tank B and the pelletizer C without being united or cut, and the strand S temperature is within a predetermined process control value range.

The computer 3 extracts a first current temperature information set consisting of two values [horizontal coordinate, measured temperature] for each point on the first detection axis 22 in the photographed data. Similarly, a second current temperature information set (an example of a current temperature information set) is extracted for each point on the second detection axis 23 . Note that the computer 3 extracts the first current temperature information set and the second current temperature information set from the original data generated by the thermo camera 2, and the first current temperature information set and the second current temperature information set are generated themselves. is performed by the thermo camera 2.

FIG. 3 is an example of plotting the second current temperature information set, and it can be seen that the maximum value 31 and the minimum value 32 appear alternately. Here, the seven local maxima 31 correspond to the temperatures of the strands S ₁ to S ₇ on the second sensing axis 23, respectively.

The computer 3 specifies the maximum value coordinates x ₁ to x ₇ at which the measured temperature has a maximum value 31 and the minimum value coordinates t ₁ to t ₆ at which the measured temperature has a minimum value 32 . Also, a temperature Tf between the maximum and minimum values of the plot is set as a filter value, and only data with a measured temperature equal to or higher than Tf are treated as valid data. That is, Tf is the minimum temperature value treated as valid data. Then, as shown in FIG. 3, the peak widths w ₁ to w ₇ at the measurement temperature Tf are specified.

The computer 3 recognizes the number of strands S based on the number of local maximum coordinates. In this embodiment, the number of strands S recognized based on the photographed data matches the number of strands S in a normal state.

The computer 3 also determines the temperature of the strands S ₁ -S ₇ based on the local maxima on the first sensing axis 22 .

At the same time, the user of the monitoring device 1 visually confirms the discharge state of the strand S. When the user visually confirms that the discharge state of the strands S is normal to the computer 3, the computer 3 registers the second current temperature information set at the time of the input as a reference set. By this operation, an example of the temperature information set in the normal state is registered as the reference set in the computer 3 .

After that, the computer 3 periodically acquires the first current temperature information set and the second current temperature information set by the same procedure as above. Then, the number of strands S recognized based on the obtained second current temperature information set (example of current temperature information set) is compared with the number of strands S in the normal state recognized based on the reference set, and both match, it is determined that the number of strands S is normal at the time of measurement. Further, the temperatures of the strands S ₁ to S ₇ determined based on the acquired first current temperature information set are compared with a predetermined reference temperature, and the difference between the two for all the strands S ₁ to S ₇ is a predetermined value. is within the reference value, it is determined that the temperature of the strands S ₁ to S ₇ is normal. When determining that both the number of strands S and the temperature are normal, the computer 3 determines that the discharge state of the strands S is normal.

When the computer 3 determines that the discharge state of the strand S is normal, the computer 3 updates the reference set with the second current temperature information set that is the basis for the determination. That is, the reference set is always updated to the latest second current temperature information set in which the discharge state of the strand S is determined to be normal.

Next, the state of the strands S, the generated temperature information set, and the result of the arithmetic processing when the strands S are coalesced will be described. In the following description, a case where _two strands (strands S2 and _S3 ) are united will be described as an example. As shown in _FIG . 4, the strands S2 and S3 come into contact with each other before entering the water of the cooling water tank B, and enter the water as a single strand S2 _{+3 .}

FIG. 5 is an example of plotting the second current temperature information set for the state shown in FIG. Compared with the plot shown in FIG. 3, there are the following differences.

First, the number of local maximum coordinates in FIG. 5 is 6, which is less than the number of local maximum coordinates of 7 in the reference set (FIG. 3). Also, in FIG. 5, there is a high maximum 33 that is significantly higher than the other maximums 31 and indicates a higher measured temperature. In addition, the high-maximum coordinate x ₂₊₃ , where the measured temperature takes the high-maximum 33, is significantly different from any of the local maximum coordinates x ₁ -x ₇ found in the reference set. Moreover, the peak width w ₂₊₃ of the peak exhibiting the high local maximum 33 is larger than any of the peak widths w ₁ to w ₇ found in the reference set. These are caused by changes in the number of strands, heat dissipation, or displacement of the maximum value due to coalescence of the strands.

As described above, when strands S coalesce, there is a distinct change in the plot of the second current temperature information set. Based on these changes, the computer 3 determines that there is an abnormality in the manner in which the strands S are united.

Subsequently, the state of the strand S, the generated temperature information set, and the result of the arithmetic processing when the strand S is cut will be described. In the following description, the case where the strand _S5 is cut will be described as an example. As shown in FIG. ₆ , strand S5 is severed before entering the water of cooling water tank B. FIG.

FIG. 7 is an example of plotting the second current temperature information set for the state shown in FIG. Compared with the plot shown in FIG. 3, there are the following differences.

The number of local maximum coordinates in FIG. 7 is 6, which is less than the number of local maximum coordinates of 7 in the reference set (FIG. 3). On the other hand, in FIG. 7, local maximum coordinates x ₁ to x ₄ , x ₆ and x ₇ are almost unchanged compared to the reference set.

As described above, even when the strand S is cut, the plot of the second current temperature information set clearly changes. Moreover, the mode of the change is clearly different from the case where the strands S are coalesced. Based on these changes, the computer 3 determines that the strand S is cut abnormally.

As shown in FIG. 8, when the strands S overlap in the vertical direction on the second detection shaft 23, the strands are ejected independently and normally, so it should not be judged to be abnormal. However, in this case as well, the number of local maxima coordinates is less than the number of local maxima coordinates in the reference set (FIG. 9), as in the case of coalescence and truncation anomalies. However, in this case, each strand exists independently and radiates heat as usual, so the maximum value 31' corresponding to the portion where the strands overlap is equivalent to the other maximum values 31. FIG. Therefore, since the plots in FIG. 9 are different from those in FIG. 5 (union) and FIG. 7 (cutting), the computer 3 can determine that the discharge state of the strand S is not abnormal. Thus, by using the number and arrangement of the coordinates of the maximum value, the maximum value itself, and the peak width as criteria for determination, it is possible to accurately determine whether or not the discharge state of the strand S is abnormal.

[Determination flow according to the present embodiment]
Summarizing the above embodiments, FIG. 10 shows a judgment flow for judging whether or not an abnormality has occurred in the monitoring device 1 according to this embodiment. When the thermo camera 2 takes an image (100), the generated image data is transferred to the computer 3 (110). Computer 3 extracts a second set of current temperature information for each point on second sensing axis 23 and compares the number of local maximum coordinates to a reference set (120).

If the number of local maximum coordinates matches the reference set, computer 3 extracts a first set of current temperature information for each point on first sensing axis 22 . Then, each maximum value of the extracted first current temperature information set is compared with a predetermined reference temperature (131).

If the first current temperature information set has a maximum value whose difference from the predetermined reference temperature exceeds a predetermined threshold, the computer 3 determines that the temperature of the strand S is abnormal (143). . At this time, the computer 3 issues an alarm to notify the user of the abnormal temperature (144). On the other hand, if such a maximum value does not exist, the computer 3 determines that the ejection state of the strand S is normal (141). At this time, computer 3 updates the reference set with the second set of current temperature information (142). After that, the process returns to the photographing step (100) again, and the monitoring of the extruder E is continued.

If the number of local maximum coordinates does not match the reference set, computer 3 compares the peak width in the second current temperature information set to a predetermined peak width reference value (132). If the difference between the peak width in the second current temperature information set and the reference value of the peak width does not exceed a predetermined threshold value for any of the peaks, the computer 3 determines that there is an abnormality in which the strand S is cut. (145). At this time, the computer 3 issues an alarm to inform the user of the abnormality (146).

If there is a peak in which the difference between the peak width in the second current temperature information set and the reference value of the peak width exceeds a predetermined threshold, the computer 3 arranges the maximum value coordinates in the second current temperature information set and the reference set are compared (133) with the location of the local maximum coordinates in .

If the second current temperature information set includes a maximum value coordinate whose displacement from each maximum value coordinate in the reference set exceeds the reference value, the computer 3 determines that there is an abnormality in which the strands S are united. (147). At this time, the computer 3 issues an alarm to inform the user of the abnormality (146).

For all the local maximum coordinates of the second current temperature information set, if the displacement from each local maximum coordinate in the reference set is within the reference value, the computer 3 calculates each local maximum of the measured temperature in the second current temperature information set. Compare 133 with other maxima. Specifically, it is determined whether or not there is a high maximum value in which the measured temperature is greater than other maximum values.

If there is a high local maximum, computer 3 determines that there is an anomaly in the way strands S coalesce (147). At this time, the computer 3 issues an alarm to inform the user of the abnormality (146).

If no high maxima exist, computer 3 determines that strands S were photographed one above the other (148). In this case, the computer 3 determines that the discharge state of the strand S is normal. At this time, the computer 3 performs processing for correcting the peaks determined to represent the state in which the strands S overlap vertically on the second current temperature information set, and then updates the reference set (149). .

It should be noted that cutting or coalescing has a greater impact on abnormal production, so it is more important than temperature abnormalities. Therefore, the alarm (146) announcing an abnormality in disconnection or coalescence and the alarm (144) announcing an anomaly in temperature are issued in such a way that the user can recognize the difference in importance. For example, the sound, light, screen display, and the like emitted when an alarm is issued are different from each other.

[Other embodiments]
Finally, other embodiments of the monitoring device, monitoring method, and monitoring program according to the present invention will be described. It should be noted that the configurations disclosed in the respective embodiments below can also be applied in combination with configurations disclosed in other embodiments unless there is a contradiction.

In the above-described embodiment, the configuration in which the monitoring device 1 separately includes the thermocamera 2 as the temperature detection unit and the computer 3 as the calculation unit has been described as an example. However, without being limited to such a configuration, the monitoring device according to the present invention may integrally include the temperature detection section and the calculation section.

In the above-described embodiment, the configuration in which the monitoring device 1 includes the thermocamera 2 as the temperature detection unit has been described as an example. However, without being limited to such a configuration, the temperature detection unit according to the present invention is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand. Any aspect may be employed as long as the information set can be generated. For example, a plurality of contact or non-contact temperature measurement devices are installed on an axis that intersects the strand discharge direction, and a set of the location of each thermometer and the detected temperature is used as a set of coordinates and measured temperature. good too. Examples of such temperature measuring devices include thermocouples and infrared thermometers.

In the above embodiment, the configuration in which temperature information sets (first current temperature information set and second current temperature information set) are generated for both the first detection axis 22 and the second detection axis 23 has been described as an example. However, without being limited to such a configuration, the temperature detection unit according to the present invention may be capable of generating temperature information sets related to at least one detection axis.

In the above embodiment, the first detection shaft 22 is positioned immediately after the strand S is discharged from the die D, and the second detection shaft 23 is positioned just before the strand S enters the water in the cooling water tank B. The arranged configuration has been described as an example. However, without being limited to such a configuration, the detection axis in the monitoring device according to the present invention can be arranged at any position as long as it is arranged so as to intersect the discharge direction of the strands. However, as in the above embodiment, it is preferable to place the sensing axis in a region where the temperature of the strands is sufficiently higher than the ambient temperature and where defects in coalescence and cutting of the strands are likely to occur. In particular, like the second detection shaft 23 in the above-described embodiment, it is more preferable to arrange the detection shaft in the most downstream region of the region where problems of coalescence and cutting of strands may occur.

In the above-described embodiment, the configuration in which the computer 3 updates the reference set to the latest second current temperature information set determined that the discharge state of the strand S is normal has been described as an example. However, without being limited to such a configuration, the reference set may not be updated in the monitoring device according to the present invention. For example, as the reference set, a temperature information set related to a predetermined normal state or a temperature information set related to an initial normal state when a series of production starts may be consistently used. Further, when the reference set is updated in the monitoring device according to the present invention, it is not always necessary to update the reference set with the latest current temperature information set determined to be normal in the discharge state, and the update interval is arbitrary. can be set to

In the above embodiment, the computer 3 compares the current temperature information set with the reference set, and compares the number and arrangement of local maximum coordinates, the local maximum itself, and the peak width for the current temperature information set, The configuration for judging that an abnormality of coalescence or disconnection has occurred has been described as an example. However, without being limited to such a configuration, the computing unit according to the present invention can compare the current temperature information set and the reference set by any method. For example, the spacing of local maximum coordinates, the curve shape of plots, etc. can be compared. Moreover, it is not necessary to compare the number and arrangement of local maximum coordinates, the local maximum itself, and the peak width as in the above embodiment.

In the above-described embodiment, a configuration in which the strand manufacturing apparatus to be monitored by the present invention is the extruder E has been described as an example. However, without being limited to such a configuration, the monitoring device according to the present invention can monitor any device as long as it is a strand manufacturing device that continuously discharges a plurality of string-like bodies. In addition, when the strand manufacturing apparatus to be monitored by the present invention is an extruder, the extruder may be any extruder such as a single-screw extruder, a twin-screw extruder, and a multi-screw extruder.

In the above embodiment, the present invention has been described as an example of a configuration in which the extruder E that discharges a strand of resin material is monitored. However, without being limited to such a configuration, the monitoring apparatus according to the present invention is a strand manufacturing apparatus that continuously discharges a plurality of string-like bodies, and thus a manufacturing apparatus that discharges strands of any material. can be Examples of such materials include, in addition to resin materials, metals, fibers, foods, and the like.

Regarding other configurations, it should be understood that the embodiments disclosed in this specification are examples in all respects, and that the scope of the present invention is not limited by them. Those skilled in the art will easily understand that modifications can be made as appropriate without departing from the scope of the present invention. Therefore, other embodiments modified without departing from the gist of the present invention are naturally included in the scope of the present invention.

The present invention can be used, for example, as a monitoring device for an extruder included in a pelletizing device.

1: Monitoring device 2: Thermo camera 3: Computer 21: Shooting range 22: First detection axis 23: Second detection axis 31: Maximum value 32: Minimum value 33: High maximum value P: Pelletizing device E: Extruder D : Die B : Cooling water tank Bs : Guide C : Pelletizer S : Strand

Claims (16)

A monitoring device for monitoring strand manufacturing equipment that discharges a plurality of strands,
a temperature detection unit capable of generating a temperature information set, which is a set of coordinates and measured temperatures relating to a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand;
Based on a comparison between a current temperature information set, which is the temperature information set at a certain moment, and a reference set, which is the temperature information set when the strand is being discharged normally, the discharge state of the strand at that moment is determined. and a computing unit capable of determining whether an abnormality has occurred ,
The calculation unit is
With respect to the current temperature information set or the reference set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value in a curve obtained by plotting the measured temperature with respect to the coordinates,
comparing the number of the local maximum value coordinates of the current temperature information set and the number of the local maximum value coordinates of the reference set, and comparing the number of the local maximum value coordinates of the current temperature information set with the number of the local maximum value coordinates of the reference set; less than the number of local maximum coordinates, and the measured temperature at at least one of the local maximum coordinates of the current temperature information set is less than the measured temperature at the other local maximum coordinates of the current temperature information set A monitoring device that judges that an abnormality in which at least two of the strands are joined together occurs when the standard of is exceeded . A monitoring device for monitoring strand manufacturing equipment that discharges a plurality of strands,
a temperature detection unit capable of generating a temperature information set, which is a set of coordinates and measured temperatures relating to a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand;
Based on a comparison between a current temperature information set, which is the temperature information set at a certain moment, and a reference set, which is the temperature information set when the strand is being discharged normally, the discharge state of the strand at that moment is determined. and a computing unit capable of determining whether an abnormality has occurred,
The calculation unit is
With respect to the current temperature information set or the reference set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value in a curve obtained by plotting the measured temperature with respect to the coordinates,
The number of the local maximum value coordinates in the current temperature information set is less than the number of the local maximum value coordinates in the reference set, and the measured temperatures at all the local maximum value coordinates in the current temperature information set meet a predetermined reference A monitoring device that determines that an abnormality in which at least one of the strands is cut occurs when the value is within the range. A monitoring device for monitoring strand manufacturing equipment that discharges a plurality of strands,
a temperature detection unit capable of generating a temperature information set, which is a set of coordinates and measured temperatures relating to a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand;
Based on a comparison between a current temperature information set, which is the temperature information set at a certain moment, and a reference set, which is the temperature information set when the strand is being discharged normally, the discharge state of the strand at that moment is determined. and a computing unit capable of determining whether an abnormality has occurred,
The calculation unit is
With respect to the current temperature information set or the reference set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value in a curve obtained by plotting the measured temperature with respect to the coordinates,
The number of the local maximum value coordinates in the current temperature information set matches the number of the local maximum value coordinates in the reference set, and the difference between the local maximum value in the current temperature information set and a predetermined reference temperature is A monitoring device that determines that the temperature of the strand is abnormal when the coordinates of the maximum value greater than a predetermined threshold exist. A monitoring device for monitoring strand manufacturing equipment that discharges a plurality of strands,
a temperature detection unit capable of generating a temperature information set, which is a set of coordinates and measured temperatures relating to a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand;
Based on a comparison between a current temperature information set, which is the temperature information set at a certain moment, and a reference set, which is the temperature information set when the strand is being discharged normally, the discharge state of the strand at that moment is determined. and a computing unit capable of determining whether an abnormality has occurred,
having at least two sensing axes spaced apart along the ejection direction;
Based on a first current temperature information set acquired by a first detection axis located on the side closer to the strand manufacturing equipment, it is determined whether or not there is an abnormality related to the temperature of the strand, and
A monitoring device that determines whether or not there is an abnormality related to the coalescence or cutting of the strand based on a second current temperature information set acquired at a second detection axis positioned farther from the strand manufacturing equipment. 2. The monitoring device according to claim 1, wherein the reference set is the latest current temperature information set determined to be normal in the ejection state. The calculation unit is
With respect to the current temperature information set or the reference set, it is possible to identify a maximum value coordinate at which the measured temperature has a maximum value in a curve obtained by plotting the measured temperature against the coordinates,
5. Whether or not there is an abnormality in the ejection state can be determined based on a comparison of the number of coordinates of the maximum value in the current temperature information set with the number of coordinates of the maximum value in the reference set. The monitoring device according to . 7. The calculating unit according to any one of claims 1 to 3 and 6 , wherein the arrangement of the local maximum value coordinates of the current temperature information set is used as further information for determining whether or not there is an abnormality in the ejection state. monitoring equipment. The calculation unit is
For the current temperature information set or the reference set, a filter value, which is the minimum temperature value treated as valid data, can be set by selecting from values between the maximum and minimum values on the curve,
The peak width, which is the width of the peak formed between the two coordinates where the curve takes the filter value before and after the local maximum coordinate, is used as a further criterion for determining whether or not there is an abnormality in the ejection state. A monitoring device according to any one of claims 1-3, 6 and 7 . A monitoring method for monitoring strand manufacturing equipment that dispenses a plurality of strands, comprising:
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged identifying a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
identifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinates;
comparing the number of the local maximum value coordinates of the current temperature information set and the number of the local maximum value coordinates of the reference set, and comparing the number of the local maximum value coordinates of the current temperature information set with the number of the local maximum value coordinates of the reference set; less than the number of local maximum coordinates, and the measured temperature at at least one of the local maximum coordinates of the current temperature information set is less than the measured temperature at the other local maximum coordinates of the current temperature information set and determining that an anomaly in which at least two of said strands are coalescing has occurred when the value of the above is higher than a reference of . A monitoring method for monitoring strand manufacturing equipment that dispenses a plurality of strands, comprising:
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged identifying a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
identifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinates;
The number of the local maximum value coordinates in the current temperature information set is less than the number of the local maximum value coordinates in the reference set, and the measured temperatures at all the local maximum value coordinates in the current temperature information set meet a predetermined reference and determining, when the value is within the range, that at least one of the strands is broken. A monitoring method for monitoring strand manufacturing equipment that dispenses a plurality of strands, comprising:
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged identifying a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
identifying, for the current temperature information set and the reference set, a maximum coordinate at which the measured temperature takes a maximum value on a curve plotting the measured temperature against the coordinates;
The number of the local maximum value coordinates of the current temperature information set matches the number of the local maximum value coordinates of the reference set, and the difference between the local maximum value of the current temperature information set and a predetermined reference temperature is and determining that the temperature of the strand is abnormal when the local maximum coordinate is greater than a predetermined threshold. A monitoring method for monitoring strand manufacturing equipment that dispenses a plurality of strands, comprising:
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged identifying a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points, for at least two of said sensing axes;
Based on the first current temperature information set acquired by the first detection axis located on the side closer to the strand manufacturing equipment, it is determined whether there is an abnormality related to the temperature of the strand, and on the side far from the strand manufacturing equipment determining whether or not there is an abnormality related to coalescence or cutting of the strands based on a second set of current temperature information acquired in a second sensing axis located. A monitoring program for monitoring strand manufacturing equipment that dispenses a plurality of strands,
when run on a computer,
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged a reference set , which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
a function of identifying a maximum value coordinate at which the measured temperature has a maximum value on a curve obtained by plotting the measured temperature against the coordinates for the current temperature information set and the reference set;
comparing the number of the local maximum value coordinates of the current temperature information set and the number of the local maximum value coordinates of the reference set, and comparing the number of the local maximum value coordinates of the current temperature information set with the number of the local maximum value coordinates of the reference set; less than the number of local maximum coordinates, and the measured temperature at at least one of the local maximum coordinates of the current temperature information set is less than the measured temperature at the other local maximum coordinates of the current temperature information set A monitoring program that causes the computer to implement a function of judging that an abnormality in which at least two of the strands are joined occurs when the standard of is exceeded . A monitoring program for monitoring strand manufacturing equipment that dispenses a plurality of strands,
when run on a computer,
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
a function of specifying, for the current temperature information set and the reference set, a maximum value coordinate at which the measured temperature takes a maximum value on a curve obtained by plotting the measured temperature against the coordinates;
The number of the local maximum value coordinates in the current temperature information set is less than the number of the local maximum value coordinates in the reference set, and the measured temperatures at all the local maximum value coordinates in the current temperature information set meet a predetermined reference A monitoring program that causes the computer to implement a function of judging that an abnormality in which at least one of the strands is cut occurs when the value is within the range. A monitoring program for monitoring strand manufacturing equipment that dispenses a plurality of strands,
when run on a computer,
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points;
a function of identifying a maximum value coordinate at which the measured temperature has a maximum value on a curve obtained by plotting the measured temperature against the coordinates for the current temperature information set and the reference set;
The number of the local maximum value coordinates in the current temperature information set matches the number of the local maximum value coordinates in the reference set, and the difference between the local maximum value in the current temperature information set and a predetermined reference temperature is A monitoring program that causes the computer to implement a function of determining that the temperature of the strand is abnormal when the coordinates of the maximum value larger than a predetermined threshold exist. A monitoring program for monitoring strand manufacturing equipment that dispenses a plurality of strands,
when run on a computer,
A current temperature information set, which is a set of coordinates and measured temperatures of a plurality of detection points arranged on a detection axis that intersects the discharge direction of the strand at a certain moment, and the above in the state in which the strand is normally discharged a reference set, which is a set of coordinates and measured temperatures associated with a plurality of sensing points, for at least two of said sensing axes;
Based on the first current temperature information set acquired by the first detection axis located on the side closer to the strand manufacturing equipment, it is determined whether there is an abnormality related to the temperature of the strand, and on the side far from the strand manufacturing equipment A monitoring program that causes the computer to implement a function of determining whether there is an abnormality related to the coalescence or cutting of the strands based on the second current temperature information set acquired at the second detection axis located.

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