Diagnostic system and diagnostic method

Abstract

To change the manufacturing conditions for long-length products at the appropriate time, or replace the extruder components at the appropriate time.SOLUTION: The diagnostic system includes a calculation unit 301 that calculates trend information indicating changes in quality characteristics based on quality characteristic data showing known quality characteristics of the elongated body and manufacturing condition data showing manufacturing conditions during the elongated body's production, a diagnostic unit 302 that diagnoses the time when the predicted quality characteristics of the long-length body, based on the trend information calculated by the calculation unit 301, will no longer satisfy a preset threshold; and an output unit 304 that outputs manufacturing condition change information indicating that a change in manufacturing conditions is necessary by the time the predicted quality characteristics of the long-length body no longer satisfy the threshold.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a diagnostic system and a degradation diagnostic method. [Background technology]

[0002] Japanese Patent Laid-Open Publication No. 10-334737 (Patent Document 1) describes a fluorine-containing elastomer coated electric wire / cable that has remarkably excellent cut-through resistance as well as excellent tensile strength and cold resistance, and a technique for manufacturing the same. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-334737 Summary of the Invention [Problem to be solved by the invention]

[0004] Typically, long objects, such as electric wires and cables, are manufactured using a single-screw extruder with a single screw. This single-screw extruder melts the insulating coating material by controlling manufacturing conditions, such as the temperature of the cylinder and head, and then extrudes the molten material by rotating the screw to coat the core wire, thereby manufacturing an electric wire and cable. The discharge volume of the insulating coating material is controlled by the screw rotation speed, and the outer diameter of the electric wire and cable is adjusted by the core wire withdrawal speed. In recent years, there have been cases where the resin flow inside the single-screw extruder is simulated using computer-aided engineering (CAE) to derive optimal cylinder and head temperatures, screw rotation speed, and other factors, thereby optimizing the manufacturing conditions for the electric wire and cable.

[0005] However, even if optimal manufacturing conditions are derived using CAE, single-screw extruders can deteriorate over time as they continue to produce electric wire and cable over long periods of time, resulting in the desired quality characteristics being lost even when the initially optimal manufacturing conditions are used. One factor contributing to this is screw wear. Screw wear reduces the height of the screw's flight, reducing the force with which the screw rotates to transport the insulating coating material forward in the extruder. Therefore, even if the manufacturing conditions are set at the same rotation speed as a new screw, a worn screw will result in a reduced extrusion volume per unit time. To achieve the same outer diameter of an electric wire and cable as a new screw, a worn screw must be modified by increasing the screw rotation speed or slowing the core wire take-up speed. However, the timing of changes to manufacturing conditions and screw replacement depends on the operator's intuition and experience, making it difficult to change manufacturing conditions or replace the screw at the appropriate time.

[0006] Therefore, it is required to change the manufacturing conditions of the elongated body at an appropriate time or to replace the components of the extruder at an appropriate time. [Means for solving the problem]

[0007] In one embodiment, the diagnostic system includes a calculation unit that calculates trend information indicating the trend of changes in the quality characteristics based on quality characteristic data indicating known quality characteristics of the elongated body and manufacturing condition data indicating the manufacturing conditions at the time of manufacturing the elongated body, a diagnostic unit that diagnoses the time when the quality characteristics of the elongated body predicted based on the trend information calculated by the calculation unit will no longer satisfy a predetermined threshold value, and an output unit that outputs manufacturing condition change information indicating that the manufacturing conditions need to be changed by the time when the predicted quality characteristics of the elongated body will no longer satisfy the threshold value.

[0008] In one embodiment, the diagnostic method calculates trend information indicating the trend of changes in the quality characteristics based on quality characteristic data indicating the known quality characteristics of the elongated body and manufacturing condition data indicating the manufacturing conditions at the time of manufacturing the elongated body, diagnoses the time when the predicted quality characteristics of the elongated body will no longer satisfy a threshold value based on the calculated trend information, and if the predicted quality characteristics of the elongated body will no longer satisfy the threshold value, outputs manufacturing condition change information indicating that the manufacturing conditions need to be changed by that time. [Effects of the Invention]

[0009] According to one embodiment, the manufacturing conditions of the elongated body can be changed at an appropriate time, or the members of the extruder can be replaced at an appropriate time. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a configuration of a manufacturing system including a diagnostic system. [Figure 2] FIG. 1 is a schematic diagram illustrating an example of a configuration of a manufacturing system including a diagnostic system. [Figure 3] FIG. 2 illustrates an example of a hardware configuration of a diagnostic system. [Figure 4] FIG. 2 is a diagram illustrating an example of functional blocks of the diagnostic system. [Figure 5] FIG. 10 is a diagram illustrating an example of quality characteristic data. [Figure 6] FIG. 10 is a diagram illustrating an example of manufacturing condition data. [Figure 7] 10 is a flowchart illustrating an example of a diagnostic process. [Figure 8] FIG. 10 is a diagram for explaining a process for calculating a regression line. [Figure 9] FIG. 10 is a diagram illustrating an example of trend information. [Figure 10] FIG. 10 is a diagram for explaining a process for diagnosing when a threshold value is no longer satisfied. [Figure 11] FIG. 10 is a diagram for explaining the relationship between the elapsed time from the start of production and quality characteristics. DETAILED DESCRIPTION OF THE INVENTION

[0011] In all the drawings for explaining the embodiments, the same components are generally designated by the same reference numerals, and repeated explanations thereof will be omitted. In addition, hatching may be used even in plan views to make the drawings easier to understand.

[0012] The technical idea of ​​this embodiment is to diagnose when to change manufacturing conditions and when to replace extruder components based on the test results of the end of the extruded long body in order to improve the quality of the extruded long body during production.

[0013] In the technology of this embodiment, the trends in the tensile test results (tensile elongation, tensile strength) of the end of an extruded long body manufactured by an extruder having a screw for extruding resin, etc. are analyzed, and when the tensile elongation decreases to a certain extent from the reference value, the screw rotation speed is increased to restore the tensile elongation, and the tensile strength is improved by replacing the screw.

[0014] <Description of Related Art> We will explain this in the case of a long body, such as a heat-resistant insulated wire. Standards have been established for the quality characteristics of heat-resistant insulated wire, such as insulation resistance, withstand voltage, tensile strength of the insulator and sheath, heat resistance, and oil resistance, and the test methods are also specified in detail in JIS C3005, Test Methods for Rubber and Plastic Insulated Wires.

[0015] As stated in 4.16 of the same, the mechanical properties (tensile strength, tensile elongation) of the insulator and sheath of long cables such as rubber wires are to be measured by taking three or more dumbbell-shaped or tubular test pieces from the finished product and measuring them at a specified tensile speed (25-500 mm / min). For this reason, three or more pieces are cut out from the end of the finished long body, and the tensile strength and tensile elongation are calculated using a tensile tester, which are then used as the quality characteristics of the long body.

[0016] <Manufacturing system configuration> 1 and 2 are schematic diagrams showing an example of the configuration of a manufacturing system 1 including a diagnostic system 100. Fig. 1 is a schematic diagram showing an example of the configuration of an extruder 10 of the manufacturing system 1 as viewed from the Y direction. Fig. 2 is a schematic diagram showing an example of the configuration of the extruder 10 of the manufacturing system 1 as viewed from the X direction in the head 31 of Fig. 1.

[0017] 1 and 2, the X direction, Y direction, and Z direction are defined. The X direction, Y direction, and Z direction are perpendicular to each other, but may intersect at an angle other than a perpendicular angle.

[0018] The manufacturing system 1 includes an extruder 10 and a diagnostic system 100. The extruder 10 has a single screw 33A. In this embodiment, the extruder 10 will be described in the case of predicting the quality characteristics of a heat-resistant insulated electric wire EW as an example of a long body. Note that the long body is not limited to an electric wire such as the heat-resistant insulated electric wire EW. For example, the long body may be anything formed by extrusion. The diagnostic system 100 is, for example, a computer system. Details of the diagnostic system 100 will be described later.

[0019] As shown in Fig. 1, extruder 10 produces heat-resistant insulated electric wire EW by coating core wire CW with resin, for example, a heat-resistant insulating material. As shown in Fig. 1, extruder 10 has drawing device 20, head 31, die 32, water tank 40 which is a cooling device, and take-up device 50. The drawing device 20, head 31, die 32, water tank 40, and take-up device 50 form an extrusion line. As shown in Fig. 2, extruder 10 has cylinder 33 connected to head 31 and material input section 34.

[0020] The drawing device 20 accommodates the core wire CW wound thereon. The drawing device 20 rotates in the direction of the arrow AR1 shown in the figure, thereby drawing out the core wire CW from the drawing device 20. The core wire CW drawn in the direction of the arrow AR2 shown in the figure passes through the head 31 and the die 32. The heat-resistant insulated electric wire EW that has passed through the head 31 and the die 32 passes through the water tank 40 and is taken up by the take-up device 50. The heat-resistant insulated electric wire EW is wound and accommodated in the take-up device 50. The arrow AR3 shown in the figure indicates the direction in which the heat-resistant insulated electric wire EW is wound.

[0021] The head 31 is connected to a cylinder 33. A heat-resistant insulating material is supplied to the head 31 from the cylinder 33. The heat-resistant insulating material supplied to the head 31 is attached to the core wire CW drawn out from the drawing device 20. The die 32 has a hole (not shown) of a predetermined size. The core wire CW with the heat-resistant insulating material attached passes through the hole of the die 32. As a result, a heat-resistant insulating material of a thickness corresponding to the size of the hole is formed on the core wire CW, and a heat-resistant insulated electric wire EW is produced.

[0022] The heat-resistant insulated electric wire EW that has passed through the die 32 passes through the water tank 40. In the water tank 40, the heat-resistant insulated electric wire EW is cooled to a predetermined temperature. The heat-resistant insulated electric wire EW cooled in this manner is taken up by the take-up device 50. In the take-up device 50, the heat-resistant insulated electric wire EW is wound at a take-up speed (hereinafter also referred to as "linear speed") and stored in the take-up device 50. Information indicating the take-up speed and a take-up current value that indicates the value of a current supplied to the take-up device 50 is transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals.

[0023] As shown in FIG. 2, a head 31 is connected to one end of a cylinder 33, and a material feeder 34 is connected to the top of the other end. Heat-resistant insulating material is fed into the material feeder 34. As indicated by the dashed arrow AR4 in the figure, the heat-resistant insulating material is fed into the cylinder 33 from the material feeder 34. The cylinder 33 has a single-axis screw 33A. The cylinder 33 is configured to rotate the screw 33A at a predetermined rotation speed depending on the amount of current supplied. As the screw 33A rotates, the heat-resistant insulating material fed from the material feeder 34 is gradually extruded toward the head 31, as indicated by the dashed arrow AR5 in the figure. The extruded heat-resistant insulating material is attached to the core wire CW within the head 31 and is extruded from the die 32 to the outside as part of the heat-resistant insulated wire EW. Information indicating the rotation speed of the screw 33A, the acceleration, the current value, and the like are transmitted to the diagnostic system 100 at predetermined intervals, for example, every one second.

[0024] Here, the screw 33A has, for example, three roles. The first role is to push the heat-resistant insulating material supplied from the material feed section 34 toward the head 31 so that it reaches the head 31. At this time, residual heat is applied to the heat-resistant insulating material. The second role is to change the heat-resistant insulating material from a solid state to a molten state. The third role is to stably extrude a constant amount of heat-resistant insulating material from the die 32.

[0025] A core wire temperature sensor S11, which is one of the detectors, is provided between the drawing device 20 and the head 31. The core wire temperature sensor S11 detects the temperature of the core wire CW between the drawing device 20 and the head 31. The temperature detected by the core wire temperature sensor S11 is transmitted to the diagnostic system 100 at predetermined intervals, for example, at intervals of one second.

[0026] As shown in FIG. 1, the head 31 is provided with a head temperature sensor S12 and a die temperature sensor S13. The head temperature sensor S12 and the die temperature sensor S13 are each detectors. The head temperature sensor S12 is a sensor that detects the head temperature of the head 31. The die temperature sensor S13 is a sensor that detects the die temperature of the die 32. In addition, a neck temperature sensor S14, which is one of the detectors, is provided near the joint between the cylinder 33 and the head 31 (see FIG. 2). The neck temperature sensor S14 is a sensor that detects the neck temperature near the joint between the cylinder 33 and the head 31. The head temperature, die temperature, and neck temperature detected by the head temperature sensor S12, die temperature sensor S13, and neck temperature sensor S14, respectively, are each transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals.

[0027] A water tank temperature sensor S15, which is one of the detectors, is provided in the water tank 40. The water tank temperature sensor S15 is a sensor that detects the water temperature of the water tank 40. The temperature detected by the water tank temperature sensor S15 is transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals.

[0028] An outer diameter measuring sensor S16, which is one of the detectors, is provided between the water tank 40 and the take-up device 50. The outer diameter measuring sensor S16 is a sensor that detects the size of the outer diameter of the heat-resistant insulated electric wire EW after it has been cooled in the water tank 40. The size of the outer diameter detected by the outer diameter measuring sensor S16 is transmitted to the diagnostic system 100 at predetermined intervals, for example, at intervals of one second.

[0029] 2, a resin temperature sensor S17 and a resin pressure sensor S18 are provided near the connection portion of the cylinder 33 with the head 31. The resin temperature sensor S17 and the resin pressure sensor S18 are each detectors. The resin temperature sensor S17 is a sensor that detects the resin temperature of the heat-resistant insulating material supplied to the head 31. The resin pressure sensor S18 is a sensor that detects the resin pressure value (also referred to as the tip resin pressure value) of the heat-resistant insulating material supplied to the head 31. The resin temperature and resin pressure values ​​detected by the resin temperature sensor S17 and the resin pressure sensor S18 are each transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals.

[0030] Five temperature sensors S21 to S25 are provided on the cylinder 33 along the longitudinal direction from the material charging section 34 side. Each of the five temperature sensors S21 to S25 is a detector. This allows the temperature of the cylinder 33 to be detected at multiple positions along the longitudinal direction of the cylinder 33. The number of temperature sensors is not limited to five and may be, for example, three, four, or six or more. The temperatures detected by the five temperature sensors S21 to S25 are transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals. As described above, the cylinder 33 has three roles. By providing multiple temperature sensors S21 to S25, the diagnostic system 100 can detect changes in the temperature of the cylinder 33 in each role.

[0031] An air temperature sensor S31 and a humidity sensor S32 are disposed around the extruder 10, for example, around the cylinder 33. The air temperature sensor S31 and the humidity sensor S32 are each detectors. The temperature detected by the air temperature sensor S31 and the humidity detected by the humidity sensor S32 are each transmitted to the diagnostic system 100 at predetermined intervals, for example, at one-second intervals.

[0032] <Hardware configuration> Next, the hardware configuration of the diagnostic system 100 in this embodiment will be described. Fig. 3 is a diagram showing an example of the hardware configuration of the diagnostic system 100 in this embodiment. Note that the configuration shown in Fig. 3 merely shows an example of the hardware configuration of the diagnostic system 100, and the hardware configuration of the diagnostic system 100 is not limited to the configuration shown in Fig. 3 and may be other configurations.

[0033] 3, a diagnostic system 100 includes a CPU (Central Processing Unit) 101 that executes a program. This CPU 101 is electrically connected to, for example, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, and a hard disk drive 112 via a bus 113, and is configured to control these hardware devices.

[0034] The CPU 101 is also connected to input devices and output devices via a bus 113. Examples of input devices include a keyboard 105, a mouse 106, a communication port 107, and a scanner 111. Examples of output devices include a display 104, a communication port 107, and a printer 110. The CPU 101 may also be connected to, for example, a removable disk device 108 and a CD / DVD-ROM device 109. The communication port 107 is connected to, for example, a cylinder 33, a drawing device 20, a take-up device 50, a core wire temperature sensor S11, a head temperature sensor S12, a die temperature sensor S13, a neck temperature sensor S14, a water tank temperature sensor S15, an outer diameter measurement sensor S16, a resin temperature sensor S17, a resin pressure sensor S18, temperature sensors S21 to S25, an air temperature sensor S31, and a humidity sensor S32.

[0035] The diagnostic system 100 may be connected to, for example, a network. For example, when the diagnostic system 100 is connected to other external devices via a network, a communication port 107 constituting a part of the diagnostic system 100 is connected to a LAN (Local Area Network), a WAN (Wide Area Network), or the Internet.

[0036] RAM 103 is an example of volatile memory, and the storage media of ROM 102, removable disk device 108, CD / DVD-ROM device 109, and hard disk device 112 are examples of non-volatile memory. These volatile and non-volatile memories constitute the storage device of diagnostic system 100.

[0037] The hard disk drive 112 stores, for example, an operating system (OS) 201, a program group 202, and a file group 203. The programs included in the program group 202 are executed by the CPU 101 using the operating system 201. The RAM 103 also temporarily stores at least some of the programs of the operating system 201 and application programs executed by the CPU 101, as well as various data required for processing by the CPU 101.

[0038] A BIOS (Basic Input Output System) program is stored in ROM 102, and a boot program is stored in hard disk drive 112. When diagnostic system 100 is started up, the BIOS program stored in ROM 102 and the boot program stored in hard disk drive 112 are executed, and operating system 201 is started up by the BIOS program and the boot program.

[0039] The program group 202 stores programs that realize the functions of the diagnostic system 100, and these programs are read and executed by the CPU 101. The file group 203 stores information, data, signal values, variable values, and parameters indicating the results of processing by the CPU 101 as file items. The program group 202 includes, for example, a diagnostic program 2021, which will be described later.

[0040] The file group 203 includes quality characteristic data 2031 and manufacturing condition data 2032. The quality characteristic data 2031 is data indicating the quality characteristics of the heat-resistant insulated electric wire EW. More specifically, the quality characteristic data 2031 is data indicating the results of a quality test when an end of the manufactured heat-resistant insulated electric wire EW is cut off and the cut off end is subjected to a quality test such as a destructive test. The manufacturing condition data 2032 is data indicating the manufacturing conditions when the heat-resistant insulated electric wire EW is manufactured. More specifically, the manufacturing condition data 2032 is data acquired from the extruder 10 and detectors (sensors S11 to S18, S21 to S25, S31, S32) installed in the extruder 10 when the heat-resistant insulated electric wire EW is manufactured.

[0041] The files are stored in a storage medium such as the hard disk drive 112 or memory. The information, data, signal values, variable values, and parameters stored in the storage medium such as the hard disk drive 112 or memory are read into the main memory or cache memory by the CPU 101 and used for operations of the CPU 101, such as extraction, search, reference, comparison, calculation, processing, editing, output, printing, and display. For example, during the above-mentioned operation of the CPU 101, the information, data, signal values, variable values, and parameters are temporarily stored in the main memory, registers, cache memory, buffer memory, etc.

[0042] The functions of diagnostic system 100 may be realized by firmware stored in ROM 102, or may be realized by software alone, hardware alone such as elements, devices, boards, and wiring, a combination of software and hardware, or even a combination of firmware and firmware. Firmware and software are stored as programs in a storage medium such as hard disk drive 112, removable disk drive 108, or CD / DVD-ROM drive 109. The programs are read and executed by CPU 101. For example, the programs cause a computer to function as diagnostic system 100.

[0043] As described above, diagnostic system 100 is a computer that includes CPU 101, which is a processing device, hard disk drive 112 and memory, which are storage devices, keyboard 105, mouse 106, and communication port 107, which are input devices, and display 104, printer 110, and communication port 107, which are output devices. The functions of diagnostic system 100 are realized by using the processing device, storage device, input device, and output device.

[0044] <Function block> FIG. 4 is a diagram illustrating an example of functional blocks of the diagnostic system 100. 4, diagnostic system 100 includes calculation unit 301, diagnosis unit 302, determination unit 303, and output unit 304. Details of the functions realized by calculation unit 301, diagnosis unit 302, determination unit 303, and output unit 304 will be described later.

[0045] <Quality characteristic data> Fig. 5 is a diagram showing an example of quality characteristic data 2031. As shown in Fig. 5, the quality characteristic data 2031 includes production number data 2031A, production date and time data 2031B, tensile strength data 2031C, and tensile elongation data 2031D. Each production number data 2031A is associated with production date and time data 2031B, tensile strength data 2031C, and tensile elongation data 2031D.

[0046] The production number data 2031A is data for identifying the manufactured heat-resistant insulated electric wire EW. The production date and time data 2031B is data indicating the date and time when the heat-resistant insulated electric wire EW was manufactured. The tensile strength data 2031C and the tensile elongation data 2031D are data indicating the quality characteristics of the heat-resistant insulated electric wire EW. The tensile strength data 2031C is data indicating the results of a quality test of the tensile strength of the end of the heat-resistant insulated electric wire EW. The tensile elongation data 2031D is data indicating the results of a quality test of the tensile elongation of the end of the heat-resistant insulated electric wire EW. The quality test is not limited to the tensile strength and tensile elongation of the end. For example, the quality characteristics may also be flame retardancy and oil resistance.

[0047] As shown in FIG. 5, the production number data 2031A includes, for example, data in which the production number "AAA" is associated with the production date "2024 / XX / YY AA:BB", the tensile strength "X1", and the tensile elongation "Y1".

[0048] <Manufacturing condition data> Fig. 6 is a diagram showing an example of manufacturing condition data 2032. As shown in Fig. 6, the manufacturing condition data 2032 includes production number data 2032A, screw rotation speed data 2032B, cylinder temperature data 2032C, head temperature data 2032D, etc. Each production number data 2032A is associated with screw rotation speed data 2032B, cylinder temperature data 2032C, head temperature data 2032D, etc.

[0049] The production number data 2032A is data for identifying the manufactured heat-resistant insulated wire EW. The screw rotation speed data 2032B is data indicating the rotation speed of the screw 33A when the heat-resistant insulated wire EW is manufactured. The cylinder temperature data 2032C is data indicating the temperature of the cylinder 33 when the heat-resistant insulated wire EW is manufactured. In this embodiment, the cylinder temperature is detected by five sensors, namely, temperature sensors S21 to S25. Therefore, the cylinder temperature data 2032C stores the average temperature of the temperatures detected by the five temperature sensors S21 to S25. Alternatively, the temperatures detected by the five temperature sensors S21 to S25 may be stored individually. The head temperature data 2032D is data indicating the temperature of the head 31 when the heat-resistant insulated wire EW is manufactured.

[0050] As shown in FIG. 6, the manufacturing condition data 2032 includes data in which, for example, a production number "AAA" is associated with a screw rotation speed "A1", a cylinder temperature "B1", a head temperature "C1", and so on.

[0051] <Diagnosis processing> Next, the diagnostic processing will be described. Fig. 7 is a flowchart showing an example of the diagnostic processing. The diagnostic processing is realized by reading out the diagnostic program 2021 stored in the hard disk drive 112 and executing it in the CPU 101. The processing shown in Fig. 7 is started when, for example, an operator executes a predetermined instruction using the keyboard 105 and mouse 106 of the diagnostic system 100.

[0052] In step ST101, the CPU 101 calculates trend information. The processing of step ST101 realizes the function of the calculation unit 301. The calculation unit 301 calculates trend information indicating a trend of changes in the quality characteristics based on quality characteristic data 2031 indicating known quality characteristics of the heat-resistant insulated electric wire EW and manufacturing condition data 2032 indicating manufacturing conditions at the time of manufacturing the heat-resistant insulated electric wire EW. In this embodiment, tensile strength and tensile elongation are specified as the quality characteristics. Therefore, trend information is calculated for each of the tensile strength and tensile elongation. In this processing, the tensile elongation will be described, but trend information is similarly calculated for the tensile strength.

[0053] FIG. 8 is a diagram for explaining the process of calculating the regression line L1. In FIG. 8, the horizontal axis represents the screw rotation speed, and the vertical axis represents the tensile elongation. In FIG. 8, the heat-resistant insulated electric wires EW produced by the extruder 10 are displayed based on the screw rotation speed and the tensile elongation value. The regression line L1 shown as a straight line in FIG. 8 represents the correlation between the screw rotation speed and the tensile elongation. The coefficient of determination R 2 is 0.5.

[0054] FIG. 9 is a diagram showing an example of trend information L3. In FIG. 9, the horizontal axis represents elapsed time, and the vertical axis represents the magnitude of tensile elongation. CPU 101 can calculate trend information L3, which indicates a trend in changes in the quality characteristics of heat-resistant insulated electric wires EW to be manufactured in the future, by using line L2 obtained from the actual measurement value G1 of screw 33A currently being used and regression line L1 calculated from the known rotation speed of screw 33A and the magnitude of tensile elongation. As shown in FIG. 9, line L2, shown by a solid line, calculated based on the actually measured magnitude of tensile elongation is fitted to regression line L1 to calculate trend information L3, shown by a dashed line.

[0055] Next, in step ST102, the CPU 101 diagnoses the time when the threshold value will no longer be satisfied. The threshold value is stored in advance, for example, in the file group 203 of the hard disk drive 112. The processing of step ST102 realizes the function of the diagnosing unit 302. The diagnosing unit 302 diagnoses the time when the quality characteristics of the heat-resistant insulated electric wire EW predicted based on the trend information calculated by the calculating unit 301 will no longer satisfy the threshold value.

[0056] FIG. 10 is a diagram illustrating the process of diagnosing when the threshold value will no longer be satisfied. The reference value RE1 is, for example, the average value of the tensile elongation of heat-resistant insulated electric wires EW manufactured in the past. The threshold value D1 is, for example, a value indicating an allowable range from the reference value RE1 of tensile elongation. The threshold value is set to a value 10% lower than the reference value of the quality characteristic. The time T corresponding to the intersection of the trend information L3 and the threshold value D1 is the time when it is necessary to increase the rotation speed of the screw 33A by a predetermined number or to replace the screw 33A. Although not shown in the figure, the same process as for the tensile elongation is also performed for the tensile strength.

[0057] Next, in step ST103, the CPU 101 performs a process of adding a predetermined number of rotations to the current number of rotations of the screw. Here, the current number of rotations of the screw is the number of rotations of the screw that is a manufacturing condition of the heat-resistant insulated electric wire EW being manufactured in the manufacturing system 1.

[0058] Next, in step ST104, the CPU 101 determines whether the rotation speed is equal to or greater than the limit rotation speed. The processing of step ST104 realizes the function of the determination unit 303. When the predicted quality characteristics of the heat-resistant insulated electric wire EW no longer satisfy the threshold value D1, the determination unit 303 determines whether the screw rotation speed increased by a predetermined number from the current rotation speed of the screw 33A is equal to or greater than the limit rotation speed. Here, the limit rotation speed is a rotation speed that affects the quality of the heat-resistant insulated electric wire EW. For example, the limit rotation speed is a rotation speed at which the screw 33A rotates at a high speed, which affects the physical properties of the heat-resistant insulating member. The limit rotation speed may be set in advance in the file group 203, for example.

[0059] If the determination in step ST104 is NO, that is, if the determination unit 303 determines that the rotation speed increased by the predetermined number of rotations is not equal to or greater than the limit rotation speed, the CPU 101 outputs manufacturing condition change information in step ST105. The manufacturing condition change information is information indicating that the manufacturing conditions need to be changed by the calculated time. For example, information indicating that the number of rotations of the screw 33A needs to be increased a predetermined number of times by time T is output. In this embodiment, since tensile strength and tensile elongation are listed as quality characteristics, information indicating quality characteristics that will no longer satisfy the threshold value may also be included.

[0060] Furthermore, if the determination in step ST104 is YES, that is, if the determination unit 303 determines that the rotation speed increased by the predetermined number of rotations is equal to or greater than the limit rotation speed, the CPU 101 outputs screw replacement information in step ST106. The screw replacement information is information indicating that replacement of the screw 33A is necessary. For example, information indicating that replacement of the screw 33A is necessary by time T is output. In this embodiment, since tensile strength and tensile elongation are listed as quality characteristics, information indicating quality characteristics that will no longer satisfy the threshold value may also be included.

[0061] The manufacturing condition change information or the screw replacement information is displayed, for example, on the display 104 of the diagnostic system 100. Furthermore, the processing of steps ST105 and ST106 realizes the function of the output unit 304. When the processing of steps ST105 and ST106 ends, the processing shown in FIG. 7 ends.

[0062] Therefore, the diagnostic system 100 can output, for example, information indicating by when the heat-resistant insulated electric wire EW needs to be changed or by when the screw 33A needs to be replaced in response to an instruction from an operator. By visually checking the output of the diagnostic system 100 on the display 104 or the like, the operator can change the manufacturing conditions for the heat-resistant insulated electric wire EW at the appropriate time or replace the screw 33A of the extruder 10 at the appropriate time. In other words, the diagnostic system 100 can appropriately predict in advance changes in control conditions that have conventionally been made by the operator's intuition or experience. Because the operator can visually check the appropriate time to replace the screw 33A, the operator can easily and appropriately plan the replacement of the screw 33A.

[0063] By visually checking the output of the diagnostic system 100, the worker can change the manufacturing conditions of the extruder 10 or replace components of the extruder 10 before the quality characteristic falls below the threshold value. Therefore, the manufacturing system 1 can prevent the quality characteristic of the heat-resistant insulated electric wire EW manufactured by the extruder 10 from falling below the threshold value D1.

[0064] <Example> Next, an example will be described. This embodiment describes a case where an extruder 10 having a single screw 33A produces a heat-resistant insulated electric wire EW, and the rotation speed of the screw 33A is changed and the screw 33A is replaced before the quality characteristics of the produced heat-resistant insulated electric wire EW deteriorate.

[0065] The quality characteristics are the tensile strength and tensile elongation specified in JIS C3005. The heat-resistant insulating material covering the core wire CW is mainly made of fluororubber. More specifically, the composition of the heat-resistant insulating material is as follows: Tetrafluoroethylene-propylene copolymer 70 parts by weight Ethylene-tetrafluoroethylene copolymer 30 parts by weight Crosslinking aid 1 part by weight Lubricant 1 part by weight Here, the tetrafluoroethylene-propylene copolymer has a number average molecular weight of 100,000. The ethylene-tetrafluoroethylene copolymer has an MP of 235°C and an MI of 30. The crosslinking aid is triallyl isocyanurate. The lubricant is barium stearate.

[0066] The diameter of the screw 33A used in the extruder 10 is 75 mm, and the cylinder temperature is fixed at 240° C. The heat-resistant insulated electric wire EW is manufactured by the extruder 10 thus specified.

[0067] Figure 11 is a diagram illustrating the relationship between the elapsed time from the start of production and quality characteristics. Figure 11(a) is a diagram illustrating the relationship between the elapsed time and the measured value of tensile elongation. Figure 11(b) is a diagram illustrating the relationship between the elapsed time and the measured value of tensile strength.

[0068] The period P1 is a period during which the extruder 10 produced the heat-resistant insulated electric wire EW without executing the diagnostic process of this embodiment. The period P2 is a period during which the extruder 10 produced the heat-resistant insulated electric wire EW after increasing the rotation speed of the screw 33A a predetermined number of times. The period P3 is a period during which the next change in the screw rotation speed or the timing for replacing the screw 33A is predicted after replacing the screw 33A. The reference value RE1 is the average value of the tensile elongation during the period P1. The threshold value D1 is a value 10% lower than the reference value RE1. The reference value RE2 is the average value of the tensile strength during the period P1. The threshold value D2 is a value 10% lower than the reference value RE2.

[0069] The trends in the tensile strength and tensile elongation over time are shown for period P1. As shown in Figure 11(b), no particular change was observed in the tensile strength, but as shown in Figure 11(a), a clear downward trend was observed in the tensile elongation.

[0070] Therefore, we checked whether there were any changes in the tensile elongation and tensile strength during period P2, when the rotation speed of the screw 33A was increased by a predetermined number to produce heat-resistant insulated electric wires EW. During period P2, as shown in Figure 11(b), no significant change was observed in the tensile strength, but as shown in Figure 11(a), there was an improvement of about 10% in the tensile elongation (indicated by the arrow AR21 in the figure).

[0071] Next, it was confirmed whether there were any changes in the tensile elongation and tensile strength during the period P3 in which the heat-resistant insulated electric wire EW was produced after replacing the screw 33A of the extruder 10. During the period P3, no change was observed in the tensile elongation as shown in Fig. 11(a), but an improvement of about 14% was observed in the tensile strength (indicated by the arrow AR22 in the figure) as shown in Fig. 11(b).

[0072] The diagnostic system 100 calculates a regression line based on the magnitude of tensile elongation during period P1, for example, based on the operator's operation. Then, by fitting the regression line to line L2 obtained from the actual measured values ​​of the magnitude of tensile elongation during period P3 after the screw 33A replacement, the diagnostic system 100 can calculate trend information L3, shown by the dashed line in the figure. Using this trend information L3, the diagnostic system 100 can predict that the next time to change the rotation speed of the screw 33A or replace the screw 33A will be at time T120. The diagnostic system 100 displays on the output device a message indicating that the rotation speed of the screw 33A needs to be increased or that the screw 33A needs to be replaced by time T120. By visually checking the output, the operator can plan a course of action for the screw 33A. This prevents the tensile elongation of the heat-resistant insulated electric wire EW produced by the extruder 10 from falling below threshold D1. In other words, the extruder 10 can consistently produce heat-resistant insulated electric wire EW with quality characteristics that meet or exceed the target.

[0073] In the above description, the manufacturing condition change information and the screw replacement information are output as separate pieces of information, but this is not limiting. For example, the manufacturing condition change information may include screw replacement information. In this case, screw replacement is specified as one of the manufacturing conditions to be changed.

[0074] The invention made by the inventor has been specifically described above based on the embodiments thereof, but it goes without saying that the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the invention. [Explanation of symbols]

[0075] 1. Manufacturing System 10 Extruder 20 Pull-out device 33A screw 100 Diagnostic Systems 101 CPU 104 Display 112 Hard disk drive 202 Programs 2021 Diagnostic Program 203 files 2031 Quality characteristic data 2032 Manufacturing Condition Data 301 Calculation Unit 302 Diagnostic Department 303 Judgment section 304 Output section CW core wire EW Heat-resistant insulated wire L1 regression line L3 Trend Information

Claims

1. a calculation unit that calculates trend information indicating a trend of change in the quality characteristics based on quality characteristic data indicating known quality characteristics of the elongated body and manufacturing condition data indicating manufacturing conditions at the time of manufacturing the elongated body; a diagnosis unit that diagnoses a time when the quality characteristics of the elongated body predicted based on the trend information calculated by the calculation unit will no longer satisfy a preset threshold value; an output unit that outputs manufacturing condition change information indicating that the manufacturing conditions need to be changed by the time when the predicted quality characteristics of the elongated body do not satisfy the threshold; A diagnostic system comprising:

2. 10. The diagnostic system of claim 1, the elongated body is extruded by rotating a screw provided in a cylinder, the production condition is the rotation speed of the screw, the manufacturing condition change information is information indicating that the rotation speed of the screw is to be increased by a predetermined number of rotations; Diagnostic system.

3. 3. The diagnostic system according to claim 2, a determination unit that determines whether the rotation speed increased by the predetermined number of rotations is equal to or greater than a limit rotation speed when the predicted quality characteristic of the elongated body does not satisfy the threshold value; the output unit outputs manufacturing condition change information indicating that the manufacturing conditions need to be changed by the time when the determination unit determines that the rotation speed increased by the predetermined rotation speed is not equal to or greater than a limit rotation speed. Diagnostic system.

4. 4. The diagnostic system according to claim 3, the output unit outputs screw replacement information indicating that the screw needs to be replaced when the determination unit determines that the rotation speed increased by the predetermined rotation speed is equal to or greater than a limit rotation speed. Diagnostic system.

5. 10. The diagnostic system of claim 1, The elongated body is an electric wire, The quality characteristic is the tensile strength or tensile elongation of the elongated body. Diagnostic system.

6. Calculating trend information indicating a trend of change in the quality characteristics based on quality characteristic data indicating known quality characteristics of the elongated body and manufacturing condition data indicating manufacturing conditions at the time of manufacturing the elongated body; diagnosing a time when the predicted quality characteristics of the elongated object will no longer satisfy a threshold based on the calculated trend information; If the predicted quality characteristics of the elongated body do not satisfy the threshold value, outputting manufacturing condition change information indicating that the manufacturing conditions need to be changed by the time. Diagnostic methods.

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