Seal failure detection system and seal failure detection method

Abstract

This invention provides a seal defect detection system that can accurately and efficiently detect whether or not a seal defect has occurred. [Solution] The seal defect detection system comprises: a temperature measurement unit; a temperature acquisition unit that acquires the temperatures of multiple measurement points measured by the temperature measurement unit; a first determination unit that determines whether any of the temperatures of the multiple measurement points acquired by the temperature acquisition unit are within a predetermined temperature range for which an upper and lower temperature limit has been set in advance; a second determination unit that determines whether the temperatures of a predetermined number of consecutive measurement points among the multiple measurement points acquired by the temperature acquisition unit are less than or equal to a predetermined first temperature difference; and a seal defect detection unit that detects that a seal defect has occurred in the packaging if the first determination unit determines that any of the temperatures of the multiple measurement points are not within the predetermined temperature range, or if the second determination unit determines that the temperatures of a predetermined number of consecutive measurement points are greater than the first temperature difference.

Description

Technical Field

[0001] The present disclosure relates to a seal defect detection system and a seal defect detection method.

Background Art

[0002] Techniques related to a heat seal line control device for heat-sealing a packaging material have been disclosed (see, for example, Patent Document 1). The heat seal line control device disclosed in Patent Document 1 detects the temperature at each point along the width direction of the heat seal portion and controls the heating conditions of the sealing machine so that the detected temperature falls within a predetermined appropriate temperature range.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a sealing device that seals a bag body by heat welding, if it seals with a foreign object, such as a powdery substance, bitten in, it will result in a seal defect. As a method for detecting a seal defect, visual discrimination of the seal portion can be cited. However, according to such a method, not only labor costs are incurred, but there is a high possibility of overlooking a seal defect. Especially when the package has a pattern, when the package is colored, and further when the bitten-in powdery substance in the seal portion is small, visual discrimination becomes extremely difficult and the occurrence of overlooking becomes prominent. Also, even when controlled so that the temperature detected in the seal portion falls within a predetermined appropriate temperature range as in the technique disclosed in Patent Document 1, there are cases where a seal defect cannot be detected. There is a need for a seal defect detection device that can accurately and efficiently detect whether a seal defect has occurred in a sealing device.

[0005] Therefore, one of the objectives is to provide a seal defect detection system and a seal defect detection method that can accurately and efficiently detect whether or not a seal defect has occurred. [Means for solving the problem]

[0006] The seal defect detection system according to this disclosure is a seal defect detection system for detecting seal defects in a package sealed by heating. The seal defect detection system comprises: a temperature measuring unit that sequentially measures the temperature of multiple measurement points in a sealed area along the width direction of the seal; a temperature acquisition unit that acquires the temperatures of the multiple measurement points measured by the temperature measuring unit; a first determination unit that determines whether any of the temperatures of the multiple measurement points acquired by the temperature acquisition unit are within a predetermined temperature range for which an upper and lower temperature limit has been set in advance; a second determination unit that determines whether the temperatures of a predetermined number of consecutive measurement points among the temperatures of the multiple measurement points acquired by the temperature acquisition unit are less than or equal to a predetermined first temperature difference; and a seal defect detection unit that detects that a seal defect has occurred in the package if the first determination unit determines that any of the temperatures of the multiple measurement points are not within the predetermined temperature range, or if the second determination unit determines that the temperatures of a predetermined number of consecutive measurement points are greater than the first temperature difference. [Effects of the Invention]

[0007] According to the above-described seal defect detection system and seal defect detection method, it is possible to accurately and efficiently detect whether or not a seal defect has occurred. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram schematically showing the configuration of the seal defect detection system in Embodiment 1. [Figure 2] Figure 2 is a schematic perspective view showing the appearance of a sealing device and a portion of the sealing failure detection system shown in Figure 1. [Figure 3] Figure 3 is a schematic diagram showing an example of a control panel included in a sealing device. [Figure 4] Figure 4 is a schematic enlarged view showing the sealed area near the opening of a sealed package. [Figure 5] Figure 5 shows an example of measurement locations in the sealing area. [Figure 6] Figure 6 is a magnified view of the display shown in Figure 3. [Figure 7] Figure 7 is a flowchart showing a typical process for detecting a seal defect using a seal defect detection system. [Figure 8] Figure 8 shows an example of how a display shows a seal failure when a relatively large amount of powdery foreign matter gets caught in the screen. [Figure 9] Figure 9 is a schematic diagram of the seal area when a relatively large amount of powdery foreign matter is trapped inside. [Figure 10] Figure 10 shows an example of how a display shows a seal failure when a relatively small amount of powdery foreign matter gets caught in the screen. [Figure 11] Figure 11 is a schematic diagram of the sealing area when a relatively small amount of powdery foreign matter is trapped inside. [Figure 12] Figure 12 shows an example of a display when a seal is tilted and a sealing defect occurs. [Figure 13] Figure 13 is a schematic diagram of the seal area when the seal is tilted. [Figure 14] Figure 14 shows an example of how the display shows when a sealing defect occurs due to wrinkles forming in the sealing area. [Figure 15] Figure 15 is a schematic diagram of the seal area when wrinkles have formed in the seal area. [Modes for carrying out the invention]

[0009] [Summary of the Embodiment] The seal defect detection system of this disclosure is a seal defect detection system for detecting seal defects in a package sealed by heating. The seal defect detection system comprises: a temperature measuring unit that sequentially measures the temperature of multiple measurement points in a sealed area along the width direction of the seal; a temperature acquisition unit that acquires the temperatures of the multiple measurement points measured by the temperature measuring unit; a first determination unit that determines whether any of the temperatures of the multiple measurement points acquired by the temperature acquisition unit are within a predetermined temperature range for which an upper limit temperature and a lower limit temperature have been set in advance; a second determination unit that determines whether the temperatures of a predetermined number of consecutive measurement points among the temperatures of the multiple measurement points acquired by the temperature acquisition unit are less than or equal to a predetermined first temperature difference; and a seal defect detection unit that detects that a seal defect has occurred in the package if the first determination unit determines that any of the temperatures of the multiple measurement points are not within the predetermined temperature range, or if the second determination unit determines that the temperatures of a predetermined number of consecutive measurement points are greater than the first temperature difference.

[0010] The inventors considered the conditions for sealing defects when sealing packaging by heating. First, they focused on the fact that sealing defects occur even when the measured temperature of the sealing area is within a preset temperature range. They then realized that simply determining whether or not the temperature is within the preset temperature range is insufficient for detecting sealing defects. Through further diligent investigation, the inventors discovered that when foreign matter, such as a minute amount of powder, is caught in the seal, the temperature changes slightly from the temperature before and after measurement. The inventors further innovated and conceived the idea that even within the preset temperature range, if a minute temperature change is observed at a certain measurement point in a predetermined number of consecutive measurement points, sealing defects occur due to foreign matter being caught in the seal, etc., and thus the present invention was formed.

[0011] According to the seal defect detection system according to the present disclosure, if it is determined by the first determination unit that the temperature is not within a predetermined temperature range set in advance, it is detected that there is a seal defect. Further, if it is determined by the second determination unit that the temperatures of a predetermined number of consecutive measurement locations among the temperatures of a plurality of measurement locations are each greater than a preset first temperature difference, in this case as well, it is detected that there is a seal defect. Then, even when the temperature at the measurement location is within the predetermined temperature range, a seal defect caused by foreign matter biting in or the like can be detected by using the determination based on the first temperature difference. In this case, since the seal defect is detected based on the temperatures of a plurality of measurement locations continuously measured by the thermometer measurement unit, there is no visual inspection, and the influence of the pattern and color of the package can be eliminated. Therefore, the efficiency of determining the presence or absence of a seal defect can be improved. From the above, according to the above seal defect detection system, it is possible to accurately and efficiently detect whether a seal defect has occurred.

[0012] In the above seal defect detection system, a third determination unit may be further provided to determine whether the difference between the maximum temperature and the minimum temperature among the temperatures of a plurality of measurement locations is less than or equal to a preset second temperature difference. If it is determined by the third determination unit that the difference between the maximum temperature and the minimum temperature among the temperatures of a plurality of measurement locations is greater than the preset second temperature difference, the seal defect detection unit may detect that a seal defect has occurred in the package.

[0013] The present inventor has found that when properly sealed, that is, when no seal defect has occurred, the difference between the maximum temperature and the minimum temperature at all measurement locations often falls within a predetermined range. That is, it was further found that if the difference between the maximum temperature and the minimum temperature deviates from the above predetermined range, there is a high possibility that a seal defect has occurred. According to the above seal defect detection system, if it is determined by the third determination unit that the difference between the maximum temperature and the minimum temperature among the temperatures of a plurality of measurement locations is greater than the second temperature difference, since the package has detected the occurrence of a seal defect, it is possible to detect more accurately whether a seal defect has occurred.

[0014] The above seal defect detection system may further include a notification control unit that controls to notify the detection result by the seal defect detection unit. By doing so, the user can easily grasp that a seal defect has occurred in the package through notification by the notification control unit that appeals to, for example, vision or hearing. Then, by using the notification result by the notification control unit, adjustment and control of the sealing device can be performed, and it is possible to make it difficult for seal defects to occur. Therefore, it is possible to further improve convenience.

[0015] In the above seal defect detection system, the temperature measurement unit may measure the temperatures of a plurality of measurement locations while moving the package. By doing so, the temperature can be measured by fixing the location where the temperature is measured by the temperature measurement unit, and the temperature of the sealed area of the package can be measured more appropriately. Also, it becomes easier to incorporate it into an intermediate process when moving the package on the production line, and productivity can be improved.

[0016] In the above seal defect detection system, the temperature measurement unit may measure the temperatures of a plurality of measurement locations in the seal area without contact. By doing so, the temperature of the measurement location can be measured more efficiently and stably. Therefore, seal defects can be detected with higher accuracy.

[0017] In the above seal defect detection system, the measurement speed by the temperature measurement unit may be 1.5 m (milliseconds) per time or less. By doing so, the number of measurements by the temperature measurement unit can be made sufficiently large, and the risk of overlooking a seal defect at a location where a foreign object has bitten in microscopically can be greatly reduced. Therefore, it is possible to more reliably determine the presence or absence of seal defects.

[0018] In the above-described seal defect detection system, the notification control unit may be controlled to notify by displaying a message on the display indicating that a seal defect has occurred. In this way, the user can understand that a seal defect has occurred by looking at the screen displayed on the display. Therefore, the user can recognize the seal defect more easily visually.

[0019] In the above-described seal defect detection system, the notification control unit may be controlled to notify the system if it does not detect a seal defect by the seal defect detection unit. By doing so, it is possible to easily understand whether a seal defect occurred during the sealing process, thereby improving work efficiency.

[0020] In the seal defect detection system described above, the notification control unit may be controlled to graph and display the relationship between the temperature at multiple measurement points acquired by the temperature acquisition unit and the elapsed time. By doing so, the relationship between the graphed temperature changes and the elapsed time can be easily grasped visually, and it is easy to recognize whether the seal defect detection unit's judgment of whether the seal defect has been detected is correct or not.

[0021] In the seal failure detection system described above, the seal failure detection unit may detect that a seal failure has occurred due to foreign matter being caught in the seal area if the second determination unit determines that the temperature of each of a predetermined number of consecutive measurement points is greater than the first temperature difference, and that the temperature is higher than the temperature of the consecutive measurement points. In this way, it is easy to recognize that the cause of the seal failure is due to foreign matter being caught. Therefore, it is easier to take measures against seal failures, such as reducing the risk of foreign matter being caught.

[0022] In the above-described seal defect detection system, the seal defect detection unit may detect that a seal defect has occurred due to a tilt in the sealing area based on the temperature changes obtained by the temperature acquisition unit. By doing so, it is easy to recognize that the cause of the seal defect is due to a tilt in the sealing area, based on the obtained temperature changes. Therefore, it becomes easier to take countermeasures against seal defects, such as correcting the tilt of the sealing area by correcting the angle deviation of the packaging before sealing.

[0023] In the above-described seal defect detection system, the seal defect detection unit may detect that a seal defect has occurred due to wrinkles forming in the sealing area if the first determination unit determines that all measurement points except the first and last measurement points are not within a predetermined temperature range, and that the temperature of all measurement points is lower than that of consecutive measurement points. In this way, it is easy to recognize that the cause of the seal defect is the formation of wrinkles (gathers) in the sealing area. Therefore, it becomes easier to take measures against seal defects, such as sufficiently removing static electricity from the packaging before sealing.

[0024] The sealing defect detection method according to this disclosure is a sealing defect detection method for detecting a sealing defect in a package sealed by heating, comprising: a temperature measurement step of sequentially measuring the temperature of a plurality of measurement points in a sealed area along the width direction of the seal; a temperature acquisition step of acquiring the temperatures of the plurality of measurement points measured in the temperature measurement step; a first determination step of determining whether any of the temperatures of the plurality of measurement points acquired in the temperature acquisition step are within a predetermined temperature range for which an upper limit temperature and a lower limit temperature have been set in advance; a second determination step of determining whether the temperatures of a predetermined number of consecutive measurement points among the temperatures of the plurality of measurement points acquired in the temperature acquisition step are less than or equal to a predetermined first temperature difference; and a sealing defect detection step of detecting that a sealing defect has occurred in the package if the first determination step determines that any of the temperatures of the plurality of measurement points are not within the predetermined temperature range, or if the second determination step determines that the temperatures of a predetermined number of consecutive measurement points are greater than the first temperature difference.

[0025] This method for detecting seal defects allows for accurate and efficient detection of whether or not a seal defect has occurred.

[0026] The above-described method for detecting a seal defect may further include a third determination step of determining whether the difference between the maximum and minimum temperatures among the multiple measurement points is less than or equal to a preset second temperature difference. The seal defect detection step may also detect that a seal defect has occurred in the packaging if the third determination step determines that the difference between the maximum and minimum temperatures among the multiple measurement points is greater than the preset second temperature difference.

[0027] By doing so, it becomes possible to detect with greater accuracy whether or not a sealing defect has occurred.

[0028] [Specific examples of embodiments] Next, an example of a specific embodiment of the seal defect detection system of this disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are given the same reference numerals, and their descriptions will not be repeated.

[0029] (Embodiment 1) The configuration of the seal defect detection system in Embodiment 1 of this disclosure will now be described. Figure 1 is a schematic block diagram showing the configuration of the seal defect detection system in Embodiment 1. Figure 2 is a schematic perspective view showing the appearance of the sealing device and a part of the seal defect detection system shown in Figure 1. Figure 3 is a schematic diagram showing an example of a control panel included in the sealing device. Figure 4 is a schematic enlarged view showing the area near the input opening, which is the sealed area of ​​the sealed package.

[0030] Referring to Figures 1, 2, 3, and 4, the seal defect detection system 11 in Embodiment 1 detects seal defects in a package 12 that has been sealed by heating. A sealing device 13 is used when sealing the package 12. The sealing device 13 includes a heater bar 14 that is heated to a temperature at which the package 12 can be welded, and a control panel 15 having a display 16 that is used to control the sealing device 13. The sealing device 13 seals the input port 17, which is the opening of the package 12, by heating. Specifically, after a predetermined amount of powdered material is put into the inside of the package 12, the package 12 is transported to the area where the heater bar 14 is located. Then, the heater bar 14 is pressed against the sealing area 18, which is the area of ​​the input port 17 to be sealed, and heated to seal it. The sealing area 18 is provided in an area close to the end of the package 12 where the input port 17 is located. As the package 12, a resin that can be welded by heating, specifically a polyolefin film, is used. In this embodiment, the case in which the contents placed in the packaging 12 are in powder form is described, but the contents are not limited to powder; for example, they may be liquid or granular, or simply solid.

[0031] The seal defect detection system 11 includes a radiation thermometer 21 as a temperature measuring unit and a seal defect detection device 22. The radiation thermometer 21 sequentially measures the temperature at multiple measurement points in the sealed area 18 that is sealed along the width direction of the seal. The width direction of the seal is the direction indicated by arrow D in Figure 4. The radiation thermometer 21 measures the temperature at multiple measurement points non-contact by measuring the temperature of the area including a fixed point in the sealed area 18 while moving the package 12. Specifically, the radiation thermometer 21 is attached to a part of the sealing device 13 and is fixed in a position that allows periodic measurement of the sealed area 18 of the package 12 being transported by the sealing device 13.

[0032] Figure 5 shows an example of measurement locations in the sealing region 18. In Figure 5, multiple measurement locations 19A, 19B, 19C, and 19D are shown as hatched areas. Also in Figure 5, the sealing region 18 is shown as a dashed line. In Figure 5, for ease of understanding, measurement locations 19A, 19B, 19C, and 19D are selected and shown, but in reality there are many more measurement locations, arranged more continuously, that is, the measurement locations marked with circles are slightly shifted in position. Referring to Figure 5 as well, the radiation thermometer 21 measures the temperatures of measurement locations 19A to 19D in order along the direction indicated by arrow D in Figure 5. In this embodiment, the starting point of the measurement locations is measurement location 19A, and the ending point is measurement location 19D. The measurement speed by the radiation thermometer 21 is 1.5 msec / measurement or less. That is, the time required for one measurement by the radiation thermometer 21 is 1.5 msec or less. Furthermore, from the viewpoint of sufficiently improving measurement accuracy and optimizing the amount of information required for processing, it is preferable that the measurement speed of the radiation thermometer 21 be between 0.7 msec / measurement and 1.5 msec / measurement. In this embodiment, the measurement speed of the radiation thermometer 21 is 1 msec / measurement.

[0033] Next, the configuration of the seal defect detection device 22 will be described. The seal defect detection device 22 includes a seal defect detection device interface unit 24 for connecting the seal defect detection device 22 to external equipment, a seal defect detection device control unit 25 for controlling the seal defect detection device 22 itself, and a seal defect detection device storage unit 26 for storing data in the seal defect detection device 22. The seal defect detection device 22 is mainly composed of a PLC (Programmable Logic Controller) having a CPU (Central Processing Unit). The seal defect detection device interface unit 24 is connected to the radiation thermometer 21 and the sealing device 13 by wire or wireless connection and functions as a transmitting unit for transmitting data and a receiving unit for receiving data. In this embodiment, the seal defect detection device storage unit 26 consists of a memory area in the CPU of the PLC and stores data such as temperature data received from the radiation thermometer 21 by the receiving unit. The seal defect detection device storage unit 26 may be a non-volatile memory built into the seal defect detection device 22 or an external hard disk.

[0034] The seal defect detection device control unit 25 is composed of a CPU and the like, and includes a temperature acquisition unit 27, a first determination unit 31, a second determination unit 32, a third determination unit 33, a seal defect detection unit 34, and a notification control unit 35. The temperature acquisition unit 27 acquires the temperatures of multiple measurement points measured by the radiation thermometer 21. The seal defect detection device interface unit 24 is used to acquire the temperatures. The first determination unit 31 determines whether any of the temperatures of the multiple measurement points acquired by the temperature acquisition unit 27 are within a predetermined temperature range for which upper and lower limits have been set in advance. The second determination unit 32 determines whether the temperatures of a predetermined number of consecutive measurement points among the multiple measurement points acquired by the temperature acquisition unit 27 are less than or equal to a preset first temperature difference. The third determination unit 33 determines whether the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference. The seal defect detection unit 34 detects a seal defect in the packaging 12 if the first determination unit 31 determines that the temperature of any of the multiple measurement points is not within a predetermined temperature range, or if the second determination unit 32 determines that the temperatures of each of a predetermined number of consecutive measurement points are greater than a first temperature difference. The seal defect detection unit 34 also detects a seal defect in the packaging 12 if the third determination unit 33 determines that the difference between the maximum temperature and the minimum temperature of the multiple measurement points is greater than a preset second temperature difference. The notification control unit 35 controls the system to notify the detection results from the seal defect detection unit 34. These configurations will be described in detail later.

[0035] The display 16 will show predetermined information. The display 16 is a touch panel; that is, information can be entered by touching the screen. Now, let's explain the display on the display 16. Figure 6 is an enlarged view of the display 16 shown in Figure 3. Referring to Figure 6, the upper area of ​​the display 16 displays various data, including a "Seal Temperature Trend Graph" display 41, a display 42A indicating that the device is currently checking for seal defects, a button 42B that, when clicked, transitions to a screen displaying the history of seal defects, a display 42C indicating that the currently detected seal is normal, the word "OK" and the number below it 43A showing the cumulative number of packages 12 with normal seals, the word "NG" and the number below it showing the cumulative number of packages 12 with abnormal seals 43B, the word "Yield" and the number below it showing the ratio of packages 12 with normal seals to the total number 43C, a display 44A visually indicating the start position of the measurement including an arrow, and a display 44B visually indicating the end position of the measurement including an arrow. The central area of ​​the display 16 displays a graph 45A showing the trend of the measured temperature. The vertical axis of Graph 45A shows the measured temperature (°C), and the horizontal axis of Graph 45A shows the elapsed time (m seconds).Furthermore, the lower area of ​​the display 16 displays the following: the words "Measurement Time" and a numerical value below it 46A indicating the measurement time for temperature measurement; the words "Start Delay" and a numerical value below it 46B indicating the delay in the start of temperature measurement; the words "Inspection Start Point" and a numerical value below it 46C indicating the timing of the start of inspection; the words "Inspection End Point" and a numerical value below it 46D indicating the timing of the end of inspection; the words "Upper Temperature" and a numerical value below it 46E indicating the upper temperature within a predetermined temperature range; and the lower temperature within a predetermined temperature range The display shows the following: the words "Lower Temperature Limit" indicating the upper temperature limit and the numerical value below it (46F); the words "Judgment Interval" indicating the determination interval for the first temperature difference, i.e., a predetermined number of consecutive measurement points (46G) and the numerical value below it (46G); the words "Interval Temperature Difference" indicating the first temperature difference, i.e., the interval temperature difference and the numerical value below it (46H); the words "Total Temperature Difference" indicating the second temperature difference, the total temperature difference and the numerical value below it (46I); and the words "Scan Time Adjustment" indicating the adjusted scan time and the numerical value below it (46J). In other words, according to the display on this display 16, the upper temperature limit is set to 115°C, the lower temperature limit to 82°C, the judgment interval to 15, the interval temperature difference to 7.0°C, and the total temperature difference to 13.0°C. The specific processing using these will be described in detail later.

[0036] Next, a method for detecting a seal defect using the seal defect detection system 11 in this embodiment will be described. Figure 7 is a flowchart showing a typical process for detecting a seal defect using the seal defect detection system 11.

[0037] Referring to Figure 7, first, the packaging 12 containing the powdered material is sealed by the sealing device 13. Then, as a temperature measurement step, the temperature of measurement points 19A to 19D in the sealed area 18 of the sealed packaging 12 is measured by a radiation thermometer 21 (step S11 in Figure 7; "step" is omitted hereafter). The measurement speed by the radiation thermometer 21 is 1.5 msec / time or less. In this embodiment, it is 1 msec / time. Then, as a temperature acquisition step, the temperatures of measurement points 19A to 19D measured by the radiation thermometer 21 are acquired by the temperature acquisition unit 27 included in the seal defect detection control unit 25 of the seal defect detection device 22 via the seal defect detection device interface unit 24, etc. (S12). Note that the temperature measurement of these measurement points is performed continuously at multiple measurement points in the sealed area 18 that is sealed along the width direction of the seal (direction indicated by arrow D in Figure 5). Furthermore, the temperature data acquired at the measurement points is stored in the seal defect detection device storage unit 26 along with the data at the measurement points.

[0038] Subsequently, the seal defect detection device control unit 25 determines whether or not the temperature of all measurement points in the seal area 18 of the packaging body 12 has been acquired (S13). Temperature measurement by the radiation thermometer 21 and temperature acquisition by the temperature acquisition unit 27 are repeated until the temperature of all measurement points has been acquired.

[0039] If the seal defect detection device control unit 25 determines that it has acquired the temperature of all measurement points (YES in S13), it is determined that it has finished measuring the temperature of all measurement points in the seal area 18 of one package 12. Then, various determinations are made as to whether or not a seal defect has occurred. In this embodiment, first, as a third determination step, the third determination unit 33 determines whether or not the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference (S14). In this embodiment, as the overall temperature difference, which is the second temperature difference, 13.0℃ is selected as shown in Figure 6.

[0040] If the third determination unit 33 determines that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference (YES in S14), then in the first determination step, the first determination unit 31 determines whether the acquired temperature at the measurement point is within a predetermined temperature range for which an upper and lower temperature limit has been set in advance (S15). In this embodiment, as shown in Figure 6, a value of 115°C is selected as the preset upper temperature limit, and a value of 82°C is selected as the preset lower temperature limit.

[0041] If the temperature of the measurement location obtained by the first determination unit 31 is determined to be within a predetermined temperature range (YES in S15), then in the second determination step, the second determination unit 32 determines whether the temperatures of a predetermined number of consecutive measurement locations among the multiple measurement locations are less than or equal to a preset first temperature difference (S16). In this embodiment, as shown in Figure 6, 7.0°C is selected as the interval temperature difference, which is the first temperature difference.

[0042] If the second determination unit 32 determines that the temperatures of a predetermined number of consecutive measurement points among the temperatures of multiple measurement points are less than or equal to a preset first temperature difference (YES in S16), the seal defect detection unit 34 does not detect that a seal defect has occurred as part of the seal defect detection process. In other words, it detects that the sealing was performed normally. As part of the notification control process, the notification control unit 35 notifies that the sealing was performed normally as a result of the detection by the seal defect detection unit 34 (S17). Specifically, the word "Normal" is displayed on the display 16. An example of graph 45A when the sealing was performed normally is shown in Figure 6.

[0043] Furthermore, in S14, if the third determination unit 33 does not determine that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference (NO in S14), the seal defect detection unit 34 detects that a seal defect has occurred as part of the seal defect detection process (S18). Also, even if YES is determined in S14, if the temperature of the measurement point acquired by the first determination unit 31 is not determined to be within a predetermined temperature range in S15 (NO in S15), that is, if the temperature of the measurement point acquired by the first determination unit 31 is determined to be higher than the upper limit temperature or lower than the lower limit temperature and is not within the predetermined temperature range, the seal defect detection unit 34 also detects that a seal defect has occurred as part of the seal defect detection process (S18). Even if the result in S15 is YES, if the second determination unit 32 does not determine in S16 that the temperatures of a predetermined number of consecutive measurement points among the temperatures of multiple measurement points are less than or equal to a preset first temperature difference (NO in S16), the seal defect detection unit 34 will detect that a seal defect has occurred in this case as part of the seal defect detection process (S18). Then, the notification control unit 35 will notify that a seal defect has occurred as a result of the detection by the seal defect detection unit 34 as part of the notification control process (S19). Specifically, the display 16 will be controlled to display a message indicating that a seal defect has occurred, for example, "abnormal". The notification control unit 35 may not only notify by displaying on the display 16, but also by flashing light, or by appealing to hearing or touch with a buzzer or vibration.

[0044] In this embodiment, if a sealing defect is detected, an NG signal is sent to the sealing device 13. Upon receiving the NG signal, the sealing device 13 uses an NG product discharge mechanism provided on the sealing device 13 side to automatically discharge the defective products, i.e., the NG products, out of the line, i.e., on a different lane from the OK products. In this way, the sealing of the packaging 12 can continue without stopping the production line.

[0045] Figure 8 shows an example of the display on the display 16 when a relatively large amount of powdery foreign matter is caught in the seal, resulting in a seal failure. Figure 9 is a schematic diagram of the seal area 18 when a relatively large amount of powdery foreign matter is caught in it. Referring to both Figures 8 and 9, even when a large amount of powdery matter 51 is caught in the seal area 18 at the position indicated by the white arrow V1 in the figure, according to graph 45B, the temperature of the measurement point in the seal area 18 is within a predetermined temperature range. In other words, the first judgment unit 31 alone cannot detect a seal failure and would judge it as normal. However, at the position indicated by the white arrow V1, the second judgment unit 32 determines that the temperature of a predetermined number of consecutive measurement points among multiple measurement points is greater than a preset first temperature difference, so it is possible to detect that a seal failure has occurred.

[0046] Figure 10 shows an example of the display on the display 16 when a seal failure occurs due to a relatively small amount of powdery foreign matter being caught in the seal. Figure 11 is a schematic diagram of the seal area 18 when a relatively small amount of powdery foreign matter is caught in it. Figure 11 also shows an enlarged view of the area where the small amount of powdery foreign matter is caught. Referring to both Figures 10 and 11, if a small amount of powdery matter 52 is caught in the seal area 18 at the position indicated by the white arrow V2 in the figure, according to graph 45C, the temperature of the measurement point in the seal area 18 is within the predetermined temperature range, similar to the cases shown in Figures 8 and 9 above. In other words, in this case as well, the first judgment unit 31 alone cannot detect the seal failure and will judge it as normal. However, at the position indicated by the white arrow V2, the second judgment unit 32 determines that the temperature of a predetermined number of consecutive measurement points among the multiple measurement points is greater than the preset first temperature difference, so it is possible to detect that a seal failure has occurred.

[0047] The seal defect detection unit 34 may also detect that a seal defect has occurred due to a tilt in the seal area 18 based on the temperature changes obtained by the temperature acquisition unit 27. Specifically, this is detected by the shape of the graph shown on the display 16. In this way, it is easy to recognize that the cause of the seal defect is the tilt in the seal area 18, based on the temperature changes obtained. Therefore, it becomes easier to take countermeasures against seal defects, such as correcting the angle of the package 12 before sealing to correct the tilt in the seal area 18.

[0048] Figure 12 shows an example of the display on the display 16 when a seal defect occurs due to a tilted seal. Figure 13 is a schematic diagram of the seal area 18 when the seal is tilted. In Figure 13, the graph when the seal is not tilted is shown by a dashed line. Referring to Figures 12 and 13 together, if the seal area 18 is tilted due to, for example, an error during the transport of the package 12, according to graph 45D, the temperature at the measurement point gradually rises in the initial stages of measurement. Also, the time it takes to reach the minimum temperature after the start of measurement is long. From the shape of such graph 45D based on the temperature changes acquired by the temperature acquisition unit 27, it is possible to detect that a seal defect has occurred due to the tilting of the seal area 18.

[0049] Figure 14 shows an example of the display on the display 16 when a sealing defect occurs due to wrinkles (gathers) in the sealing area 18. Figure 15 is a schematic diagram of the sealing area 18 when wrinkles have occurred in the sealing area 18. Referring to Figures 14 and 15, for example, if wrinkles 53 occur in the area 54 indicated by the white arrow V3 in the figure within the sealing area 18 due to an error during the transport of the package 12, then, according to graph 45E, if the first determination unit 31 determines that the temperature is not within a predetermined temperature range and is lower than the temperature of the consecutive measurement points, it is possible to detect that wrinkles 53 have occurred in the sealing area 18 and a sealing defect has occurred.

[0050] As described above, with this seal defect detection system 11, if the first determination unit 31 determines that the temperature is not within a predetermined temperature range, a seal defect is detected. Also, if the second determination unit 32 determines that the temperatures of a predetermined number of consecutive measurement points among multiple measurement points are greater than a predetermined first temperature difference, a seal defect is detected in this case as well. In this way, even if the temperature of the measurement points is within the predetermined temperature range, seal defects caused by foreign matter jamming, etc., can be detected using the determination based on the first temperature difference. In this case, since the seal defect is detected based on the temperatures of multiple measurement points continuously measured by the radiation thermometer 21, visual inspection is not required, and the influence of the pattern and color of the packaging 12 can be eliminated. Therefore, the efficiency of determining whether or not a seal defect is present can be improved. As described above, it is possible to accurately and efficiently detect whether or not a seal defect has occurred.

[0051] In this embodiment, a third determination unit 33 is included that determines whether the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference. If the third determination unit 33 determines that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is greater than the preset second temperature difference, the seal defect detection unit 34 detects that a seal defect has occurred in the package 12.

[0052] According to the seal defect detection system 11 described above, if the third determination unit 33 determines that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is greater than the second temperature difference, the package 12 has detected a seal defect, thus enabling detection of whether or not a seal defect has occurred with higher accuracy.

[0053] In this embodiment, the seal defect detection system 11 includes a notification control unit 35 that controls the system to notify the detection results of the seal defect detection unit 34. Therefore, the user can easily understand that a seal defect has occurred in the packaging 12 through notification from the notification control unit 35, for example, by appealing to their senses, such as sight or hearing. Then, by utilizing the notification results from the notification control unit 35, the sealing device 13 can be adjusted or controlled to make it less likely for seal defects to occur. Thus, convenience can be further improved.

[0054] In this embodiment, the infrared thermometer 21 measures the temperature at multiple measurement points while moving the package 12. Therefore, the temperature can be measured by fixing the points to be measured by the infrared thermometer 21, and the temperature of the sealed area of ​​the package 12 can be measured more accurately. In addition, it can be easily incorporated into intermediate processes when moving the package 12 in the manufacturing line, thereby improving productivity.

[0055] In this embodiment, the radiation thermometer 21 measures the temperature of multiple measurement points in the sealing area 18 without contact. Therefore, the temperature of the measurement points can be measured more efficiently and stably. Consequently, sealing defects can be detected with higher accuracy.

[0056] In this embodiment, the measurement speed by the radiation thermometer 21 is 1.5 msec / measurement or less. Therefore, by increasing the number of measurements by the radiation thermometer 21, the risk of missing a sealing defect at a location where a small amount of foreign matter has become trapped can be greatly reduced. Consequently, the presence or absence of a sealing defect can be determined more reliably.

[0057] In this embodiment, the notification control unit 35 is controlled to notify the user by displaying a message on the display 16 indicating that a sealing defect has occurred. Therefore, the user can understand that there is a sealing defect by looking at the screen displayed on the display. Thus, the user can recognize the sealing defect more easily visually.

[0058] In this embodiment, the notification control unit 35 is controlled to notify the system if the seal defect detection unit 34 does not detect that a seal defect has occurred. Therefore, it is possible to easily understand whether a seal defect occurred during the sealing process, thereby improving work efficiency.

[0059] In this embodiment, the notification control unit 35 controls the system to graph and display the relationship between the temperature at multiple measurement points acquired by the temperature acquisition unit 27 and the elapsed time. Therefore, the relationship between the temperature trend and elapsed time graphed can be easily grasped visually, and it is easy to recognize whether the seal defect detection unit 34's judgment regarding the detection of a seal defect is normal or not.

[0060] In this embodiment, the seal failure detection unit 34 detects that a seal failure has occurred due to foreign matter being caught in the seal area 18 if the second determination unit 32 determines that the temperature of each of a predetermined number of consecutive measurement points is greater than the first temperature difference, and that the temperature is higher than the temperature of the consecutive measurement points. Therefore, it is easy to recognize that the cause of the seal failure is due to foreign matter being caught. Consequently, it is easier to take measures against seal failures, such as reducing the risk of foreign matter being caught.

[0061] In this embodiment, the seal defect detection unit 34 detects that a seal defect has occurred due to wrinkles forming in the seal area 18 if the first determination unit 31 determines that all measurement points except the first and last measurement points are not within a predetermined temperature range and are lower than the temperatures of consecutive measurement points. Therefore, it is easy to recognize that the cause of the seal defect is the formation of wrinkles (gathers) in the seal area. Consequently, it becomes easier to take measures against seal defects, such as sufficiently removing static electricity from the packaging before sealing.

[0062] Furthermore, the seal defect detection method according to this disclosure is a seal defect detection method for detecting a seal defect in a package 12 sealed by heating, and comprises: a temperature measurement step of sequentially measuring the temperature of a plurality of measurement points in a sealed area 18 sealed along the width direction of the seal; a temperature acquisition step of acquiring the temperatures of the plurality of measurement points measured in the temperature measurement step; a first determination step of determining whether any of the temperatures of the plurality of measurement points acquired in the temperature acquisition step are within a predetermined temperature range for which an upper limit temperature and a lower limit temperature have been set in advance; a second determination step of determining whether the temperatures of a predetermined number of consecutive measurement points among the temperatures of the plurality of measurement points acquired in the temperature acquisition step are less than or equal to a predetermined first temperature difference; and a seal defect detection step of detecting that a seal defect has occurred in the package 12 if the first determination step determines that any of the temperatures of the plurality of measurement points are not within the predetermined temperature range, or if the second determination step determines that the temperatures of a predetermined number of consecutive measurement points are greater than the first temperature difference.

[0063] This method for detecting seal defects allows for accurate and efficient detection of whether or not a seal defect has occurred.

[0064] The above-described method for detecting a seal defect may further include a third determination step of determining whether the difference between the maximum and minimum temperatures among the multiple measurement points is less than or equal to a preset second temperature difference. The seal defect detection step may also detect that a seal defect has occurred in the package 12 if the third determination step determines that the difference between the maximum and minimum temperatures among the multiple measurement points is greater than the preset second temperature difference.

[0065] By doing so, it becomes possible to detect with greater accuracy whether or not a sealing defect has occurred.

[0066] (Other embodiments) In the above embodiment, the temperature measuring unit measures the temperature of multiple measurement points in the sealing area without contact. However, the temperature measuring unit is not limited to this and may also measure the temperature by contacting the sealing area. Furthermore, in the above embodiment, the temperature measuring unit measures the temperature of multiple measurement points while moving the package. However, the temperature measuring unit is not limited to this and may also measure the temperature of multiple measurement points in the sealing area by moving the measurement point of the radiation thermometer.

[0067] Furthermore, in the above embodiment, the sealing device 13 may be included in the sealing defect detection system 11. Also, control may be performed not only by a control panel, but also from a mobile terminal device such as a notebook PC or smartphone.

[0068] In the above embodiment, the decision by the third decision unit is made first, followed by the decision by the first decision unit, and then by the decision by the second decision unit. However, the order of the decisions by the first, second, and third decision units is not limited to this. For example, the decision by the first decision unit may be made first, followed by the decision by the second decision unit, and finally by the decision by the third decision unit. Alternatively, the decision by the first decision unit may be made first, followed by the decision by the third decision unit, and finally by the decision by the second decision unit. Alternatively, the decision by the second decision unit may be made first, followed by the decision by the first decision unit, and finally by the decision by the third decision unit. Alternatively, the decision by the second decision unit may be made first, followed by the decision by the third decision unit, and finally by the decision by the first decision unit. Alternatively, the decision by the third decision unit may be made first, followed by the decision by the second decision unit, and finally by the decision by the first decision unit.

[0069] The embodiments disclosed herein should be understood to be illustrative in all respects and not restrictive in any way. The scope of the present invention is defined by the claims and is intended to include all modifications in the sense and scope equivalent to the claims. [Explanation of Symbols]

[0070] 11 Seal defect detection system, 12 Packaging, 13 Sealing device, 14 Heater bar, 15 Control panel, 16 Display, 17 Input port, 18 Sealing area, 19A, 19B, 19C, 19D Measurement points, 21 Radiation thermometer, 22 Seal defect detection device, 24 Seal defect detection device interface unit, 25 Seal defect detection device control unit, 26 Seal defect detection device memory unit, 27 Temperature acquisition unit, 31 First judgment unit, 32 Second judgment unit, 33 Third judgment unit, 34 Seal defect detection unit, 35 Notification control unit, 41, 42A, 42C, 43A, 43B, 43C, 44A, 44B, 46A, 46B, 46C, 46D, 46E, 46F, 46G, 46H, 46I, 46J Display, 42B Buttons, 45A, 45B, 45C, 45D, 45E Graphs, 51, 52 Powdered material, 53 Wrinkles, 54 Area.

Claims

1. A seal defect detection system for detecting seal defects in packaging sealed by heating, A temperature measuring unit that sequentially measures the temperature at multiple measurement points in a sealed area along the width direction of the seal, A temperature acquisition unit that acquires the temperatures of the plurality of measurement locations measured by the temperature measurement unit, A first determination unit determines whether any of the temperatures of the plurality of measurement points acquired by the temperature acquisition unit are within a predetermined temperature range for which an upper and lower temperature limit has been set in advance. A second determination unit determines whether the temperatures of a predetermined number of consecutive measurement locations among the temperatures of the plurality of measurement locations acquired by the temperature acquisition unit are less than or equal to a preset first temperature difference, A seal defect detection system comprising: a seal defect detection unit that detects that a seal defect has occurred in the packaging if the first determination unit determines that the temperature of any of the plurality of measurement locations is not within the predetermined temperature range, or if the second determination unit determines that the temperatures of each of the predetermined number of consecutive measurement locations are greater than the first temperature difference.

2. The system further includes a third determination unit that determines whether the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference. The seal defect detection system according to claim 1, wherein the seal defect detection unit detects that a seal defect has occurred in the packaging if the third determination unit determines that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is greater than the second temperature difference which is set in advance.

3. The seal defect detection system according to claim 1 or claim 2, further comprising a notification control unit that controls the system to notify the detection result of the seal defect detection unit.

4. The seal defect detection system according to claim 1 or claim 2, wherein the temperature measuring unit measures the temperature at the plurality of measurement points while moving the package.

5. The seal defect detection system according to claim 1 or claim 2, wherein the temperature measuring unit measures the temperature of the plurality of measurement locations in the seal area in a non-contact manner.

6. The seal defect detection system according to claim 1 or claim 2, wherein the measurement speed by the temperature measuring unit is 1.5 msec / time or less.

7. The seal defect detection system according to claim 3, wherein the notification control unit is controlled to notify by displaying on a display that a seal defect has occurred.

8. The seal defect detection system according to claim 3, wherein the notification control unit is controlled to notify the fact that a seal defect has occurred if the seal defect detection unit has not detected that a seal defect has occurred.

9. The seal defect detection system according to claim 3, wherein the notification control unit controls the relationship between the temperature of the plurality of measurement locations acquired by the temperature acquisition unit and the elapsed time to be graphed and displayed.

10. The seal defect detection system according to claim 1 or 2, wherein the seal defect detection unit detects that a seal defect has occurred due to foreign matter being caught in the seal area if the second determination unit determines that the temperature of each of the predetermined number of consecutive measurement locations is greater than the first temperature difference and is higher than the temperature of the consecutive measurement locations.

11. The seal defect detection system according to claim 2, wherein the seal defect detection unit detects from the temperature change obtained by the temperature acquisition unit that the seal defect has occurred due to the seal region becoming tilted.

12. The seal defect detection system according to claim 1 or 2, wherein the seal defect detection unit detects that a seal defect has occurred due to the occurrence of wrinkles in the seal region if the first determination unit determines that the measurement locations, excluding the first and last measurement locations among the plurality of measurement locations, are not within the predetermined temperature range and are lower than the temperature of the consecutive measurement locations.

13. A method for detecting seal defects in a package sealed by heating, A temperature measurement process that sequentially measures the temperature at multiple measurement points in a sealed area along the width direction of the seal, A temperature acquisition step which acquires the temperatures of the plurality of measurement locations measured by the temperature measurement step, A first determination step involves determining whether any of the temperatures of the multiple measurement points obtained in the temperature acquisition step fall within a predetermined temperature range for which an upper and lower temperature limit has been set in advance. A second determination step involves determining whether the temperatures of a predetermined number of consecutive measurement locations obtained in the temperature acquisition step are less than or equal to a predetermined first temperature difference, A method for detecting a sealing defect, comprising: a sealing defect detection step in which the first determination step determines that the temperature of any of the plurality of measurement locations is not within the predetermined temperature range, or a second determination step determines that the temperatures of each of the predetermined number of consecutive measurement locations are greater than the first temperature difference, thereby detecting that a sealing defect has occurred in the packaging.

14. The system further includes a third determination step of determining whether the difference between the maximum temperature and the minimum temperature among the multiple measurement points is less than or equal to a preset second temperature difference. The sealing defect detection method according to claim 13, wherein the sealing defect detection step detects that a sealing defect has occurred in the packaging if the third determination step determines that the difference between the maximum temperature and the minimum temperature among the multiple measurement points is greater than the second temperature difference which has been set in advance.

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