Molded product management device

Abstract

To provide a technology to accurately manage an amount of resin waste.SOLUTION: A molded product management device includes a data storage unit that stores identification information for each molded product manufactured by an injection molding machine and an amount of material loss per molded product manufactured during a set period. The amount of material loss is the amount of resin injected from the injection molding machine during the set period that does not become the molded product. The data storage unit stores the amount of material loss by dividing it into a waste amount and a recycled amount.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a molded product management device. [Background technology]

[0002] The material loss management system described in Patent Document 1 includes a material loss amount calculation unit that calculates the amount of material loss generated in a molding machine, a factor identification unit that identifies the cause of material loss, an aggregation period input device that inputs an aggregation period, a material loss amount aggregation means that aggregates the material loss amount over the aggregation period, and an aggregation result output device that outputs the aggregation results of the material loss amount.

[0003] Patent Document 2 discloses that information such as the overall operating rate of an injection molding machine, power consumption, resin consumption, pass / fail rate, and operation time is displayed. It also discloses that the molding process defect rate, inspection defect rate, and material defect rate are calculated. Furthermore, it discloses that when calculating the material pass / fail rate, the weight of materials discarded at the start of the molding process until molding stabilizes and the weight of discarded molded products may be added to the total weight of pass / fail products. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-264112 [Patent Document 2] Japanese Patent Publication No. 2022-181871 Summary of the Invention [Problem to be solved by the invention]

[0005] Calculating the amount of material loss that occurs during the process of manufacturing molded products has been studied for some time. Material loss refers to the amount of resin injected from an injection molding machine that does not become a molded product (more specifically, a non-defective product). Causes of material loss include purging when starting up the injection molding machine, test shots when adjusting molding conditions, waste shots when starting mass production, the generation of by-products during mass production, the generation of defective products during mass production, waste shots when mass production resumes, and purging when shutting down the injection molding machine.

[0006] Of the resins injected from injection molding machines, some that do not become molded parts are crushed using a crusher or other device and recycled as molding material. Therefore, the amount of material loss does not necessarily correspond to the amount of waste. As a result, it has traditionally been difficult to accurately manage the amount of waste. As a result, for example, it has been difficult to accurately calculate CO2 emissions in Category 5 of Scope 3 as defined by the GHG (Greenhouse Gas) Protocol. CO2 emissions in Category 5 of Scope 3 are CO2 emissions that can be reduced by reviewing the operation of injection molding machines.

[0007] One embodiment of the present invention provides a technique that allows for accurate management of the amount of resin waste. [Means for solving the problem]

[0008] A molded product management device according to one embodiment of the present invention has a data storage unit that stores identification information for each molded product manufactured by an injection molding machine and the amount of material loss per molded product manufactured during a set period. The amount of material loss is the amount of resin injected from the injection molding machine during the set period that does not become the molded product. The data storage unit stores the amount of material loss by dividing it into a waste amount and a recycled amount. [Effects of the Invention]

[0009] According to one embodiment of the present invention, the amount of resin to be discarded can be accurately managed. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a state when mold opening of an injection molding machine according to one embodiment is completed. [Figure 2] FIG. 2 is a diagram showing a state of the injection molding machine according to one embodiment when clamping the mold. [Figure 3] FIG. 3 is a flowchart showing an example of factors that cause material loss from start-up to shut-down of an injection molding machine. [Figure 4] FIG. 4 is a functional block diagram showing an example of components of the molded product management device. [Figure 5] FIG. 5 is a diagram illustrating an example of data stored in the data storage unit. [Figure 6] FIG. 6 is a diagram showing an example of set periods that can be adopted for each factor. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same reference numerals, and the description thereof may be omitted.

[0012] (injection molding machine) FIG. 1 is a diagram showing a state of an injection molding machine according to an embodiment when mold opening is completed. FIG. 2 is a diagram showing a state of an injection molding machine according to an embodiment when mold clamping is performed. In this specification, the X-axis direction, Y-axis direction, and Z-axis direction are perpendicular to each other. The X-axis direction and Y-axis direction represent horizontal directions, and the Z-axis direction represents vertical directions. When the mold clamping device 100 is of a horizontal type, the X-axis direction is the mold opening / closing direction, and the Y-axis direction is the width direction of the injection molding machine 10. The negative side of the Y-axis direction is called the operating side, and the positive side of the Y-axis direction is called the counter-operating side.

[0013] As shown in FIGS. 1 and 2 , injection molding machine 10 includes a mold clamping unit 100 that opens and closes mold apparatus 800, an ejector unit 200 that ejects a molded product molded by mold apparatus 800, an injection unit 300 that injects molding material into mold apparatus 800, a moving unit 400 that moves injection unit 300 forward and backward relative to mold apparatus 800, a control unit 700 that controls each component of injection molding machine 10, and a frame 900 that supports each component of injection molding machine 10. Frame 900 includes a mold clamping unit frame 910 that supports mold clamping unit 10 and an injection unit frame 920 that supports injection unit 300. Clamping unit frame 910 and injection unit frame 920 are each installed on floor 2 via leveling adjusters 930. Control unit 700 is disposed in the interior space of injection unit frame 920. Each component of injection molding machine 10 will be described below.

[0014] (mold clamping device) In the description of the mold clamping unit 100, the moving direction of the movable platen 120 during mold closing (for example, the positive X-axis direction) is defined as the front, and the moving direction of the movable platen 120 during mold opening (for example, the negative X-axis direction) is defined as the rear.

[0015] The mold clamping device 100 performs mold closing, pressure increase, mold clamping, depressurization, and mold opening of the mold device 800. The mold device 800 includes a fixed mold 810 and a movable mold 820.

[0016] The mold clamping unit 100 is, for example, a horizontal type, and the mold opening and closing direction is horizontal. The mold clamping unit 100 has a fixed platen 110 to which a fixed mold 810 is attached, a movable platen 120 to which a movable mold 820 is attached, and a movement mechanism 102 that moves the movable platen 120 relative to the fixed platen 110 in the mold opening and closing direction.

[0017] The stationary platen 110 is fixed to the mold clamping unit frame 910. A stationary mold 810 is attached to the surface of the stationary platen 110 that faces the movable platen 120.

[0018] The movable platen 120 is disposed so as to be movable in the mold opening / closing direction relative to the mold clamping unit frame 910. A guide 101 for guiding the movable platen 120 is installed on the mold clamping unit frame 910. A movable mold 820 is attached to the surface of the movable platen 120 facing the fixed platen 110.

[0019] The moving mechanism 102 moves the movable platen 120 forward and backward relative to the fixed platen 110, thereby performing mold closing, pressurization, mold clamping, depressurization, and mold opening of the mold apparatus 800. The moving mechanism 102 has a toggle support 130 arranged at a distance from the fixed platen 110, tie bars 140 connecting the fixed platen 110 and the toggle support 130, a toggle mechanism 150 that moves the movable platen 120 in the mold opening / closing direction relative to the toggle support 130, a mold clamping motor 160 that operates the toggle mechanism 150, a motion conversion mechanism 170 that converts the rotational motion of the mold clamping motor 160 into linear motion, and a mold thickness adjustment mechanism 180 that adjusts the distance between the fixed platen 110 and the toggle support 130.

[0020] The toggle support 130 is disposed at a distance from the fixed platen 110 and is placed on the mold clamping unit frame 910 so as to be freely movable in the mold opening and closing direction. The toggle support 130 may be disposed so as to be freely movable along a guide laid on the mold clamping unit frame 910. The guide of the toggle support 130 may be the same as the guide 101 of the movable platen 120.

[0021] In this embodiment, the fixed platen 110 is fixed to the mold clamping unit frame 910, and the toggle support 130 is arranged so as to be freely movable in the mold opening and closing direction relative to the mold clamping unit frame 910, but the toggle support 130 may also be fixed to the mold clamping unit frame 910, and the fixed platen 110 may be arranged so as to be freely movable in the mold opening and closing direction relative to the mold clamping unit frame 910.

[0022] The tie bars 140 connect the fixed platen 110 and the toggle support 130 at an interval L in the mold opening / closing direction. A plurality of tie bars 140 (for example, four) may be used. The plurality of tie bars 140 are arranged parallel to the mold opening / closing direction and extend according to the mold clamping force. At least one tie bar 140 may be provided with a tie bar strain detector 141 that detects strain in the tie bar 140. The tie bar strain detector 141 sends a signal indicating the detection result to the control device 700. The detection result of the tie bar strain detector 141 is used to detect the mold clamping force, etc.

[0023] In this embodiment, the tie bar strain detector 141 is used as the mold clamping force detector that detects the mold clamping force, but the present invention is not limited to this. The mold clamping force detector is not limited to the strain gauge type, and may be a piezoelectric type, a capacitance type, a hydraulic type, an electromagnetic type, or the like, and the attachment position thereof is also not limited to the tie bar 140.

[0024] The toggle mechanism 150 is disposed between the movable platen 120 and the toggle support 130 and moves the movable platen 120 relative to the toggle support 130 in the mold opening / closing direction. The toggle mechanism 150 has a crosshead 151 that moves in the mold opening / closing direction and a pair of link groups that bend and extend with the movement of the crosshead 151. Each of the pair of link groups has a first link 152 and a second link 153 that are connected to bendable and extendable by a pin or the like. The first link 152 is attached to the movable platen 120 by a pin or the like so that it can swing freely. The second link 153 is attached to the toggle support 130 by a pin or the like so that it can swing freely. The second link 153 is attached to the crosshead 151 via a third link 154. When the crosshead 151 advances or retreats relative to the toggle support 130, the first link 152 and the second link 153 bend and extend, and the movable platen 120 advances or retreats relative to the toggle support 130.

[0025] The configuration of the toggle mechanism 150 is not limited to the configuration shown in Figures 1 and 2. For example, although each link group has five nodes in Figures 1 and 2, it may have four nodes, and one end of the third link 154 may be connected to the node between the first link 152 and the second link 153.

[0026] The mold clamping motor 160 is attached to the toggle support 130 and operates the toggle mechanism 150. The mold clamping motor 160 moves the crosshead 151 forward and backward relative to the toggle support 130, thereby bending and extending the first link 152 and the second link 153 and moving the movable platen 120 forward and backward relative to the toggle support 130. The mold clamping motor 160 is directly connected to the motion conversion mechanism 170, but may also be connected to the motion conversion mechanism 170 via a belt, a pulley, or the like.

[0027] The motion conversion mechanism 170 converts the rotational motion of the mold clamping motor 160 into the linear motion of the crosshead 151. The motion conversion mechanism 170 includes a screw shaft and a screw nut that screws onto the screw shaft. A ball or roller may be interposed between the screw shaft and the screw nut.

[0028] The mold clamping unit 100 performs a mold closing process, a pressure increasing process, a mold clamping process, a pressure reducing process, a mold opening process, and the like under the control of the control device 700.

[0029] In the mold closing process, the mold clamping motor 160 is driven to move the crosshead 151 forward at a set movement speed to a mold closing completion position, thereby moving the movable platen 120 forward and bringing the movable mold 820 into contact with the fixed mold 810. The position and movement speed of the crosshead 151 are detected using, for example, a mold clamping motor encoder 161. The mold clamping motor encoder 161 detects the rotation of the mold clamping motor 160 and sends a signal indicating the detection result to the control device 700.

[0030] The crosshead position detector that detects the position of the crosshead 151 and the crosshead movement speed detector that detects the movement speed of the crosshead 151 are not limited to the mold clamping motor encoder 161, and general types can be used. Furthermore, the movable platen position detector that detects the position of the movable platen 120 and the movable platen movement speed detector that detects the movement speed of the movable platen 120 are not limited to the mold clamping motor encoder 161, and general types can be used.

[0031] In the pressure increasing step, the mold clamping motor 160 is further driven to move the crosshead 151 further forward from the mold closing completion position to the mold clamping position, thereby generating a mold clamping force.

[0032] In the mold clamping process, the mold clamping motor 160 is driven to maintain the position of the crosshead 151 at the mold clamping position. In the mold clamping process, the mold clamping force generated in the pressure increase process is maintained. In the mold clamping process, a cavity space 801 (see FIG. 2) is formed between the movable mold 820 and the fixed mold 810, and the injection device 300 fills the cavity space 801 with liquid molding material. The filled molding material is solidified to obtain a molded product.

[0033] The number of cavity spaces 801 may be one or more. In the latter case, multiple molded products are obtained at the same time. An insert material may be placed in a part of the cavity space 801, and another part of the cavity space 801 may be filled with a molding material. A molded product is obtained in which the insert material and the molding material are integrated.

[0034] In the depressurization process, the mold clamping motor 160 is driven to move the crosshead 151 back from the mold clamping position to the mold opening start position, thereby moving the movable platen 120 back and reducing the mold clamping force. The mold opening start position and the mold closing completion position may be the same position.

[0035] In the mold opening process, the mold clamping motor 160 is driven to move the crosshead 151 backward at a set moving speed from the mold opening start position to the mold opening completion position, thereby moving the movable platen 120 backward and separating the movable mold 820 from the fixed mold 810. Thereafter, the ejector unit 200 ejects the molded product from the movable mold 820.

[0036] The setting conditions for the mold closing process, pressure increase process, and mold clamping process are set together as a series of setting conditions. For example, the movement speed and position of the crosshead 151 in the mold closing process and pressure increase process (including the mold closing start position, movement speed switching position, mold closing completion position, and mold clamping position), and the mold clamping force are set together as a series of setting conditions. The mold closing start position, movement speed switching position, mold closing completion position, and mold clamping position are arranged in this order from the rear side to the front, and represent the start and end points of the section for which the movement speed is set. The movement speed is set for each section. There may be one or more movement speed switching positions. The movement speed switching position does not have to be set. Only one of the mold clamping position and the mold clamping force may be set.

[0037] The setting conditions for the depressurization process and mold opening process are also set in a similar manner. For example, the movement speed and position of the crosshead 151 in the depressurization process and mold opening process (mold opening start position, movement speed switching position, and mold opening completion position) are set together as a series of setting conditions. The mold opening start position, movement speed switching position, and mold opening completion position are arranged in this order from the front to the rear, and represent the start and end points of the section for which the movement speed is set. The movement speed is set for each section. There may be one or more movement speed switching positions. The movement speed switching position does not have to be set. The mold opening start position and mold closing completion position may be the same position. Furthermore, the mold opening completion position and mold closing start position may be the same position.

[0038] It should be noted that the moving speed and position of the movable platen 120 may be set instead of the moving speed and position of the crosshead 151. Furthermore, the clamping force may be set instead of the position of the crosshead (e.g., clamping position) or the position of the movable platen.

[0039] The toggle mechanism 150 amplifies the driving force of the mold clamping motor 160 and transmits it to the movable platen 120. The amplification factor is also called the toggle factor. The toggle factor changes depending on the angle θ between the first link 152 and the second link 153 (hereinafter also referred to as the "link angle θ"). The link angle θ is determined from the position of the crosshead 151. When the link angle θ is 180°, the toggle factor is maximum.

[0040] When the thickness of the mold device 800 changes due to replacement of the mold device 800 or a temperature change in the mold device 800, a mold thickness adjustment is performed so that a predetermined clamping force is obtained during mold clamping. In mold thickness adjustment, for example, the distance L between the fixed platen 110 and the toggle support 130 is adjusted so that the link angle θ of the toggle mechanism 150 becomes a predetermined angle at the time of mold touch when the movable mold 820 touches the fixed mold 810.

[0041] The mold clamping unit 100 has a mold thickness adjustment mechanism 180. The mold thickness adjustment mechanism 180 adjusts the mold thickness by adjusting the distance L between the fixed platen 110 and the toggle support 130. The mold thickness adjustment is performed, for example, between the end of a molding cycle and the start of the next molding cycle. The mold thickness adjustment mechanism 180 has, for example, a screw shaft 181 formed at the rear end of the tie bar 140, a screw nut 182 held rotatably and immovably by the toggle support 130, and a mold thickness adjustment motor 183 that rotates the screw nut 182 that is threaded onto the screw shaft 181.

[0042] A screw shaft 181 and a screw nut 182 are provided for each tie bar 140. The rotational driving force of the mold thickness adjustment motor 183 may be transmitted to the plurality of screw nuts 182 via a rotational driving force transmission unit 185. The plurality of screw nuts 182 can be rotated synchronously. Note that by changing the transmission path of the rotational driving force transmission unit 185, the plurality of screw nuts 182 can also be rotated individually.

[0043] The rotational drive force transmission unit 185 is composed of, for example, gears. In this case, a driven gear is formed on the outer periphery of each screw nut 182, a drive gear is attached to the output shaft of the mold thickness adjustment motor 183, and an intermediate gear that meshes with the multiple driven gears and drive gear is rotatably held in the center of the toggle support 130. Note that the rotational drive force transmission unit 185 may be composed of a belt, a pulley, or the like instead of gears.

[0044] The operation of the mold thickness adjustment mechanism 180 is controlled by a control device 700. The control device 700 drives a mold thickness adjustment motor 183 to rotate the screw nut 182. As a result, the position of the toggle support 130 relative to the tie bar 140 is adjusted, and the distance L between the fixed platen 110 and the toggle support 130 is adjusted. Note that a plurality of mold thickness adjustment mechanisms may be used in combination.

[0045] The gap L is detected using a mold thickness adjustment motor encoder 184. The mold thickness adjustment motor encoder 184 detects the amount and direction of rotation of the mold thickness adjustment motor 183, and sends a signal indicating the detection result to the control device 700. The detection result of the mold thickness adjustment motor encoder 184 is used to monitor and control the position of the toggle support 130 and the gap L. Note that the toggle support position detector that detects the position of the toggle support 130 and the gap detector that detects the gap L are not limited to the mold thickness adjustment motor encoder 184, and general detectors can be used.

[0046] The mold clamping unit 100 may have a mold temperature regulator that regulates the temperature of the mold device 800. The mold device 800 has a flow path for a temperature regulation medium inside. The mold temperature regulator regulates the temperature of the mold device 800 by regulating the temperature of the temperature regulation medium supplied to the flow path of the mold device 800.

[0047] The mold clamping unit 100 of this embodiment is a horizontal type in which the mold opening and closing direction is horizontal, but it may also be a vertical type in which the mold opening and closing direction is vertical.

[0048] Although the mold clamping unit 100 of this embodiment has a mold clamping motor 160 as a drive unit, it may have a hydraulic cylinder instead of the mold clamping motor 160. Also, the mold clamping unit 100 may have a linear motor for opening and closing the mold, and an electromagnet for mold clamping.

[0049] (Ejector device) In describing the ejector device 200, similar to the description of the mold clamping device 100, the direction of movement of the movable platen 120 when the mold is closed (e.g., the positive direction of the X-axis) is defined as the front, and the direction of movement of the movable platen 120 when the mold is opened (e.g., the negative direction of the X-axis) is defined as the rear.

[0050] The ejector unit 200 is attached to the movable platen 120 and moves forward and backward together with the movable platen 120. The ejector unit 200 has an ejector rod 210 that ejects a molded product from the mold device 800, and a drive mechanism 220 that moves the ejector rod 210 in the movement direction of the movable platen 120 (X-axis direction).

[0051] The ejector rod 210 is arranged so as to be able to move forward and backward in a through-hole of the movable platen 120. The front end of the ejector rod 210 contacts an ejector plate 826 of the movable mold 820. The front end of the ejector rod 210 may or may not be connected to the ejector plate 826.

[0052] The drive mechanism 220 includes, for example, an ejector motor and a motion conversion mechanism that converts the rotational motion of the ejector motor into linear motion of the ejector rod 210. The motion conversion mechanism includes a screw shaft and a screw nut that screws onto the screw shaft. Balls or rollers may be interposed between the screw shaft and the screw nut.

[0053] The ejector unit 200 performs an ejection process under the control of the control unit 700. In the ejection process, the ejector rod 210 is advanced from the standby position to the ejection position at a set moving speed, thereby advancing the ejector plate 826 and ejecting the molded product. After that, the ejector motor is driven to retract the ejector rod 210 at the set moving speed, and the ejector plate 826 is retracted to the original standby position.

[0054] The position and movement speed of the ejector rod 210 are detected using, for example, an ejector motor encoder. The ejector motor encoder detects the rotation of the ejector motor and sends a signal indicating the detection result to the control device 700. Note that the ejector rod position detector that detects the position of the ejector rod 210 and the ejector rod movement speed detector that detects the movement speed of the ejector rod 210 are not limited to the ejector motor encoder, and general types can be used.

[0055] (injection device) In the description of the injection device 300, unlike the description of the mold clamping device 100 and the description of the ejector device 200, the movement direction of the screw 330 during filling (e.g., the negative X-axis direction) is described as the forward direction, and the movement direction of the screw 330 during metering (e.g., the positive X-axis direction) is described as the rearward direction.

[0056] The injection unit 300 is mounted on a slide base 301, and the slide base 301 is disposed so as to be able to move forward and backward relative to the injection unit frame 920. The injection unit 300 is disposed so as to be able to move forward and backward relative to the mold unit 800. The injection unit 300 touches the mold unit 800 and fills a cavity space 801 in the mold unit 800 with a molding material. The injection unit 300 includes, for example, a cylinder 310 that heats the molding material, a nozzle 320 provided at the front end of the cylinder 310, a screw 330 that is disposed so as to be able to move forward and backward and to be able to rotate within the cylinder 310, a metering motor 340 that rotates the screw 330, an injection motor 350 that moves the screw 330 forward and backward, and a load detector 360 that detects a load transmitted between the injection motor 350 and the screw 330.

[0057] Cylinder 310 heats the molding material supplied to the interior through supply port 311. The molding material includes, for example, resin. The molding material is formed, for example, in the form of pellets and supplied to supply port 311 in a solid state. Supply port 311 is formed at the rear of cylinder 310. A cooler 312, such as a water-cooled cylinder, is provided on the outer periphery of the rear of cylinder 310. A first heater 313, such as a band heater, and a first temperature detector 314 are provided on the outer periphery of cylinder 310, ahead of cooler 312.

[0058] Cylinder 310 is divided into a plurality of zones in the axial direction (e.g., X-axis direction) of cylinder 310. A first heater 313 and a first temperature detector 314 are provided in each of the plurality of zones. A set temperature is set in each of the plurality of zones, and control device 700 controls first heater 313 so that the temperature detected by first temperature detector 314 becomes the set temperature.

[0059] The nozzle 320 is provided at the front end of the cylinder 310 and is pressed against the mold device 800. A second heater 323 and a second temperature detector 324 are provided on the outer periphery of the nozzle 320. The control device 700 controls the second heater 323 so that the detected temperature of the nozzle 320 becomes the set temperature.

[0060] The screw 330 is disposed within the cylinder 310 so as to be rotatable and movable forward and backward. When the screw 330 is rotated, the molding material is sent forward along the spiral groove of the screw 330. As the molding material is sent forward, it is gradually melted by the heat from the cylinder 310. As the liquid molding material is sent forward to the front of the screw 330 and accumulates in the front part of the cylinder 310, the screw 330 is moved backward. Thereafter, when the screw 330 is moved forward, the liquid molding material accumulated in front of the screw 330 is injected from the nozzle 320 and filled into the mold device 800.

[0061] A backflow prevention ring 331 is attached to the front of the screw 330 so as to be movable back and forth as a backflow prevention valve for preventing the molding material from flowing back from the front to the rear of the screw 330 when the screw 330 is pushed forward.

[0062] When the screw 330 is moved forward, the backflow prevention ring 331 is pushed backward by the pressure of the molding material in front of the screw 330, and moves back relative to the screw 330 to a blocking position (see FIG. 2) where it blocks the flow path of the molding material. This prevents the molding material accumulated in front of the screw 330 from flowing backward.

[0063] On the other hand, when the screw 330 is rotated, the backflow prevention ring 331 is pushed forward by the pressure of the molding material sent forward along the spiral groove of the screw 330, and moves forward relative to the screw 330 to the open position (see FIG. 1) where it opens the flow path of the molding material. This causes the molding material to be sent forward of the screw 330.

[0064] The backflow prevention ring 331 may be either a co-rotating type that rotates together with the screw 330 or a non-co-rotating type that does not rotate together with the screw 330.

[0065] The injection device 300 may have a drive source for moving the backflow prevention ring 331 back and forth relative to the screw 330 between the open position and the closed position.

[0066] The metering motor 340 rotates the screw 330. The drive source for rotating the screw 330 is not limited to the metering motor 340, and may be, for example, a hydraulic pump.

[0067] The injection motor 350 advances and retreats the screw 330. A motion conversion mechanism that converts the rotational motion of the injection motor 350 into linear motion of the screw 330 is provided between the injection motor 350 and the screw 330. The motion conversion mechanism has, for example, a screw shaft and a screw nut that screws onto the screw shaft. A ball or roller may be provided between the screw shaft and the screw nut. The drive source that advances and retreats the screw 330 is not limited to the injection motor 350 and may be, for example, a hydraulic cylinder.

[0068] The load detector 360 detects the load transmitted between the injection motor 350 and the screw 330. The detected load is converted into pressure by the control device 700. The load detector 360 is provided on the load transmission path between the injection motor 350 and the screw 330, and detects the load acting on the load detector 360.

[0069] The load detector 360 sends a signal of the detected load to the control device 700. The load detected by the load detector 360 is converted into pressure acting between the screw 330 and the molding material, and is used to control and monitor the pressure that the screw 330 receives from the molding material, the back pressure on the screw 330, the pressure that the screw 330 acts on the molding material, and the like.

[0070] The pressure detector that detects the pressure of the molding material is not limited to the load detector 360, and a general detector can be used. For example, a nozzle pressure sensor or a mold internal pressure sensor may be used. The nozzle pressure sensor is installed in the nozzle 320. The mold internal pressure sensor is installed inside the mold device 800.

[0071] The injection device 300 performs a metering process, a filling process, a pressure holding process, etc. under the control of the control device 700. The filling process and the pressure holding process may be collectively referred to as the injection process.

[0072] In the metering process, the metering motor 340 is driven to rotate the screw 330 at a set rotational speed, and the molding material is sent forward along the spiral groove of the screw 330. As this happens, the molding material gradually melts. As the liquid molding material is sent forward to the screw 330 and accumulates at the front of the cylinder 310, the screw 330 is moved backward. The rotational speed of the screw 330 is detected, for example, using a metering motor encoder 341. The metering motor encoder 341 detects the rotation of the metering motor 340 and sends a signal indicating the detection result to the control device 700. Note that the screw rotational speed detector that detects the rotational speed of the screw 330 is not limited to the metering motor encoder 341, and a general one can be used.

[0073] In the metering process, in order to restrict abrupt retraction of the screw 330, the injection motor 350 may be driven to apply a set back pressure to the screw 330. The back pressure on the screw 330 is detected using, for example, a load detector 360. When the screw 330 retracts to the metering completion position and a predetermined amount of molding material accumulates in front of the screw 330, the metering process is completed.

[0074] The position and rotational speed of the screw 330 in the metering process are set together as a series of setting conditions. For example, a metering start position, a rotational speed switching position, and a metering completion position are set. These positions are arranged in this order from the front to the rear, and represent the start and end points of the section for which the rotational speed is set. The rotational speed is set for each section. There may be one or more rotational speed switching positions. The rotational speed switching position does not have to be set. In addition, a back pressure is set for each section.

[0075] In the filling process, the injection motor 350 is driven to move the screw 330 forward at a set moving speed, and the liquid molding material accumulated in front of the screw 330 is filled into the cavity space 801 in the mold device 800. The position and moving speed of the screw 330 are detected using, for example, an injection motor encoder 351. The injection motor encoder 351 detects the rotation of the injection motor 350 and sends a signal indicating the detection result to the control device 700. When the position of the screw 330 reaches a set position, a switch from the filling process to a pressure holding process (so-called V / P switch) is performed. The position at which the V / P switch is performed is also called the V / P switch position. The set moving speed of the screw 330 may be changed depending on the position of the screw 330, time, etc.

[0076] The position and movement speed of the screw 330 in the filling process are set together as a series of setting conditions. For example, a filling start position (also called an "injection start position"), a movement speed switching position, and a V / P switching position are set. These positions are arranged in this order from rear to front, and represent the start and end points of the section for which the movement speed is set. The movement speed is set for each section. There may be one or more movement speed switching positions. The movement speed switching position does not have to be set.

[0077] An upper limit value for the pressure of the screw 330 is set for each section in which the movement speed of the screw 330 is set. The pressure of the screw 330 is detected by a load detector 360. When the pressure of the screw 330 is equal to or lower than the set pressure, the screw 330 is advanced at the set movement speed. On the other hand, when the pressure of the screw 330 exceeds the set pressure, the screw 330 is advanced at a movement speed slower than the set movement speed so that the pressure of the screw 330 is equal to or lower than the set pressure, in order to protect the mold.

[0078] It should be noted that after the position of the screw 330 reaches the V / P switching position during the filling process, the screw 330 may be temporarily stopped at the V / P switching position, and then V / P switching may be performed. Immediately before V / P switching, instead of stopping the screw 330, the screw 330 may be moved forward or backward at a slow speed. Furthermore, the screw position detector that detects the position of the screw 330 and the screw movement speed detector that detects the movement speed of the screw 330 are not limited to the injection motor encoder 351, and general detectors may be used.

[0079] In the dwelling step, the injection motor 350 is driven to push the screw 330 forward, maintaining the pressure of the molding material at the front end of the screw 330 (hereinafter also referred to as "holding pressure") at a set pressure, and pushing the molding material remaining in the cylinder 310 toward the mold device 800. This can replenish any molding material that is insufficient due to cooling contraction within the mold device 800. The holding pressure is detected, for example, using a load detector 360. The set value of the holding pressure may be changed depending on the elapsed time from the start of the dwelling step, etc. Multiple holding pressures and holding times for maintaining the holding pressure in the dwelling step may be set, or they may be set together as a series of setting conditions.

[0080] In the dwelling step, the molding material in the cavity space 801 in the mold device 800 is gradually cooled, and when the dwelling step is completed, the entrance to the cavity space 801 is blocked by the solidified molding material. This state is called a gate seal, and prevents the molding material from flowing back from the cavity space 801. After the dwelling step, the cooling step begins. In the cooling step, the molding material in the cavity space 801 is solidified. A metering step may be performed during the cooling step in order to shorten the molding cycle time.

[0081] Although the injection device 300 of this embodiment is of an in-line screw type, it may also be of a pre-plasticization type. A pre-plasticization type injection device supplies molding material molten in a plasticization cylinder to an injection cylinder, and injects the molding material from the injection cylinder into a mold device. A screw is disposed in the plasticization cylinder so that it can rotate freely but cannot move back and forth, or the screw is disposed so that it can rotate freely and move back and forth. Meanwhile, a plunger is disposed in the injection cylinder so that it can move back and forth.

[0082] Furthermore, although the injection unit 300 of this embodiment is a horizontal type in which the axial direction of the cylinder 310 is horizontal, it may be a vertical type in which the axial direction of the cylinder 310 is vertical. The mold clamping unit combined with the vertical injection unit 300 may be either a vertical type or a horizontal type. Similarly, the mold clamping unit combined with the horizontal injection unit 300 may be either a horizontal type or a vertical type.

[0083] (Mobile device) In the description of the moving device 400, similar to the description of the injection device 300, the moving direction of the screw 330 during filling (e.g., the negative X-axis direction) is defined as the front, and the moving direction of the screw 330 during metering (e.g., the positive X-axis direction) is defined as the rear.

[0084] The moving device 400 moves the injection device 300 forward and backward relative to the mold device 800. The moving device 400 also presses the nozzle 320 against the mold device 800 to generate nozzle touch pressure. The moving device 400 includes a hydraulic pump 410, a motor 420 as a drive source, a hydraulic cylinder 430 as a hydraulic actuator, and the like.

[0085] The hydraulic pump 410 has a first port 411 and a second port 412. The hydraulic pump 410 is a bidirectional pump, and by switching the rotation direction of the motor 420, it draws in hydraulic fluid (e.g., oil) from one of the first port 411 and the second port 412 and discharges it from the other, thereby generating hydraulic pressure. Note that the hydraulic pump 410 can also draw in hydraulic fluid from a tank and discharge it from either the first port 411 or the second port 412.

[0086] The motor 420 operates the hydraulic pump 410. The motor 420 drives the hydraulic pump 410 in a rotational direction and with a rotational torque according to a control signal from the control device 700. The motor 420 may be an electric motor or an electric servo motor.

[0087] The hydraulic cylinder 430 has a cylinder body 431, a piston 432, and a piston rod 433. The cylinder body 431 is fixed to the injection device 300. The piston 432 divides the interior of the cylinder body 431 into a front chamber 435 as a first chamber and a rear chamber 436 as a second chamber. The piston rod 433 is fixed to the fixed platen 110.

[0088] A front chamber 435 of the hydraulic cylinder 430 is connected to a first port 411 of the hydraulic pump 410 via a first flow path 401. The hydraulic fluid discharged from the first port 411 is supplied to the front chamber 435 via the first flow path 401, thereby pushing the injection unit 300 forward. The injection unit 300 is moved forward, and the nozzle 320 is pressed against the fixed mold 810. The front chamber 435 functions as a pressure chamber that generates nozzle touch pressure of the nozzle 320 by the pressure of the hydraulic fluid supplied from the hydraulic pump 410.

[0089] Meanwhile, the rear chamber 436 of the hydraulic cylinder 430 is connected to the second port 412 of the hydraulic pump 410 via the second flow path 402. The hydraulic fluid discharged from the second port 412 is supplied to the rear chamber 436 of the hydraulic cylinder 430 via the second flow path 402, thereby pushing the injection unit 300 backward. The injection unit 300 is moved backward, and the nozzle 320 is separated from the fixed mold 810.

[0090] In this embodiment, the moving device 400 includes the hydraulic cylinder 430, but the present invention is not limited to this. For example, instead of the hydraulic cylinder 430, an electric motor and a motion conversion mechanism that converts the rotational motion of the electric motor into the linear motion of the injection device 300 may be used.

[0091] (Control device) The control device 700 is configured, for example, by a computer, and as shown in Figures 1 and 2, has a CPU (Central Processing Unit) 701, a storage medium 702 such as a memory, an input interface 703, and an output interface 704. The control device 700 performs various controls by causing the CPU 701 to execute a program stored in the storage medium 702. The control device 700 also receives signals from the outside via the input interface 703 and transmits signals to the outside via the output interface 704.

[0092] The control device 700 repeatedly manufactures molded products by repeating processes such as a metering process, mold closing process, pressure increase process, mold clamping process, filling process, pressure dwell process, cooling process, pressure release process, mold opening process, and ejection process. A series of operations required to obtain a molded product, such as the operations from the start of a metering process to the start of the next metering process, is also called a "shot" or "molding cycle." The time required for one shot is also called the "molding cycle time" or "cycle time."

[0093] One molding cycle includes, for example, a metering process, a mold closing process, a pressurization process, a mold clamping process, a filling process, a pressure holding process, a cooling process, a depressurization process, a mold opening process, and an ejection process, in this order. The order here refers to the order in which each process starts. The filling process, the pressure holding process, and the cooling process are performed during the mold clamping process. The start of the mold clamping process may coincide with the start of the filling process. The completion of the depressurization process coincides with the start of the mold opening process.

[0094] It should be noted that, in order to shorten the molding cycle time, multiple processes may be performed simultaneously. For example, the metering process may be performed during the cooling process of the previous molding cycle, or during the mold clamping process. In this case, the mold closing process may be performed at the beginning of the molding cycle. The filling process may be started during the mold closing process. The ejection process may be started during the mold opening process. If an on-off valve for opening and closing the flow path of the nozzle 320 is provided, the mold opening process may be started during the metering process. This is because, even if the mold opening process is started during the metering process, the molding material will not leak from the nozzle 320 as long as the on-off valve closes the flow path of the nozzle 320.

[0095] One molding cycle may include steps other than the metering step, mold closing step, pressure increase step, mold clamping step, filling step, pressure holding step, cooling step, pressure release step, mold opening step, and ejection step.

[0096] For example, after the dwelling step is completed and before the metering step begins, a pre-metering suck-back step may be performed in which the screw 330 is retracted to a preset metering start position. This can reduce the pressure of the molding material accumulated in front of the screw 330 before the metering step begins, and prevent the screw 330 from retracting suddenly at the start of the metering step.

[0097] Furthermore, after the metering step is completed and before the filling step begins, a post-metering suck-back step may be performed in which the screw 330 is retracted to a preset filling start position (also referred to as the "injection start position"). This can reduce the pressure of the molding material accumulated in front of the screw 330 before the filling step begins, and can prevent the molding material from leaking from the nozzle 320 before the filling step begins.

[0098] The control device 700 is connected to an operation device 750 that accepts input operations by a user and a display device 760 that displays a screen. The operation device 750 and the display device 760 may be integrated, for example, by using a touch panel 770. The touch panel 770 serving as the display device 760 displays a screen under the control of the control device 700. The screen of the touch panel 770 may display information such as settings of the injection molding machine 10 and the current status of the injection molding machine 10. The screen of the touch panel 770 may also display operation units such as buttons and input fields that accept input operations by the user. The touch panel 770 serving as the operation device 750 detects input operations on the screen by the user and outputs signals corresponding to the input operations to the control device 700. This allows, for example, a user to operate the operation units provided on the screen while checking information displayed on the screen to perform settings of the injection molding machine 10 (including input of setting values). The user can also operate the operation units provided on the screen to cause the injection molding machine 10 to perform operations corresponding to the operation units. The operation of the injection molding machine 10 may be, for example, the operation (including stopping) of the clamping device 100, the ejector device 200, the injection device 300, the moving device 400, etc. The operation of the injection molding machine 10 may also be the switching of a screen displayed on the touch panel 770 serving as the display device 760, etc.

[0099] Although the operation device 750 and the display device 760 of this embodiment have been described as being integrated as the touch panel 770, they may be provided independently. Also, a plurality of operation devices 750 may be provided. The operation device 750 and the display device 760 are disposed on the operation side (negative Y-axis direction) of the mold clamping unit 100 (more specifically, the fixed platen 110).

[0100] (Material waste management) Next, referring to FIG. 3, an example of a factor that causes material loss from start-up to shut-down of the injection molding machine 10 will be described. The material loss is the amount of resin injected from the injection molding machine 10 that does not become a molded part (product). The molded part does not include by-products, which will be described later. By-products are substances that solidify in the internal space of the mold device 800 at the same time as the molded part, and are substances that solidify in the resin passage. The resin passage includes, for example, a sprue and a runner. The by-products are ejected from the mold device 800 by the ejector device 200 together with the molded part.

[0101] Factors that cause material loss include purging when starting up the injection molding machine 10 (step S101), test shots when adjusting molding conditions (step S102), throwaway shots when mass production begins (step S104), the generation of by-products during mass production (step S105), the generation of defective products during mass production (step S106), throwaway shots when mass production resumes (step S109), and purging when shutting down the injection molding machine 10 (step S110).

[0102] Steps S101 to S110 shown in Fig. 3 will be described below. The processing from step S101 onwards shown in Fig. 3 is started when a mass production plan for molded products is executed. Although not shown, even after the waste shot (step S109) when mass production is resumed, by-products are generated during mass production (step S105) and defective products are generated during mass production (step S106). Furthermore, although not shown, injection molding machine 10 may be temporarily stopped multiple times between startup and shutdown.

[0103] Step S101 includes purging when starting up the injection molding machine 10. Starting up the injection molding machine 10 includes raising the temperature of the cylinder 310. Raising the temperature of the cylinder 310 includes raising the temperature of the cylinder 310 to a set temperature for mass production of molded products. Purging is performed after the temperature of the cylinder 310 has been raised or during the temperature rise of the cylinder 310. Purging is an operation of discharging the resin inside the cylinder 310 to the outside of the injection molding machine 10. Purging may be performed multiple times.

[0104] Purging is performed with the nozzle 320 separated from the mold apparatus 800 to prevent the molding material from being filled into the mold apparatus 800 from the nozzle 320 provided at the front end of the cylinder 310. Purging includes, for example, an operation in which the metering motor 340 rotates the screw 330 to move it backward, and an operation in which the injection motor 350 moves the screw 330 forward. Note that purging may also include an operation in which the metering motor 340 rotates the screw 330 while the injection motor 350 prohibits the screw 330 from moving forward or backward. Furthermore, if the mold apparatus 800 has a heater that heats the resin passage (for example, the sprue and runner), purging may be performed with the nozzle 320 in contact with the mold apparatus 800.

[0105] The purging amount at start-up is an example of the amount of material loss. The purging amount can be calculated based on purging conditions. For example, the purging amount can be calculated based on at least one of the rotation amount of the metering motor 340 and the rotation amount of the injection motor 350. The advance amount of the screw 330 may be used instead of the rotation amount of the injection motor 350. The cross-sectional area of ​​the cylinder 310, the number of purgings, etc. may also be used to calculate the purging amount. The density of the resin may also be used to calculate the purging amount. The calculation of the purging amount may be performed by the user of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages multiple control devices 700. The purging amount may also be measured using a weight scale.

[0106] Step S102 includes a trial molding when adjusting the molding conditions. The trial molding includes actually performing the metering process, mold closing process, pressure increase process, mold clamping process, filling process, pressure dwell process, cooling process, pressure release process, mold opening process, and ejection process, just like in mass production of molded products. Trial molding may be repeated under different molding conditions until the quality of the molded product obtained in the trial molding meets the desired standard. The quality of the molded product is evaluated, for example, by at least one of the dimensions, shape, weight, and color.

[0107] The test shot amount is an example of the amount of material loss. The test shot amount can be calculated based on molding conditions. For example, the test shot amount can be calculated based on the cross-sectional area of ​​the cylinder 310, the advancement amount of the screw 330, and the density of the resin. The test shot amount may be calculated by the user of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages multiple control devices 700. The test shot amount may also be measured using a weighing scale.

[0108] The trial injection amount may be calculated based on the volume of the internal space of the mold device 800 and the density of the resin. The internal space of the mold device 800 includes a resin passage and a cavity space 801 provided at the end of the resin passage. There may be multiple cavity spaces 801, and the resin passage may be branched, with a cavity space 801 at the end of each of the multiple branches.

[0109] Step S103 includes the start of mass production of molded products. Mass production of molded products starts after the start-up of the injection molding machine 10 and the adjustment of molding conditions are completed. Mass production of molded products is carried out under the adjusted molding conditions.

[0110] Step S104 includes a throwaway shot at the start of mass production. Since the quality of molded products is unstable immediately after the start of mass production, molded products obtained by the throwaway shot may be treated as defective products. The number of throwaway shots is set in advance.

[0111] The amount of waste shots at the start of mass production is an example of the amount of material loss. The amount of waste shots can be calculated based on molding conditions. For example, the amount of waste shots can be calculated based on the cross-sectional area of ​​the cylinder 310, the advancement amount of the screw 330, and the density of the resin. The calculation of the amount of waste shots may be performed by the user of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages multiple control devices 700. The amount of waste shots may also be measured using a weighing scale.

[0112] The amount of waste shots at the start of mass production may be calculated based on the volume of the internal space of the mold apparatus 800 and the density of the resin. The internal space of the mold apparatus 800 includes a resin passage and a cavity space 801 provided at the end of the resin passage. There may be multiple cavity spaces 801, or the resin passage may be branched, with a cavity space 801 at the end of each of the multiple branches.

[0113] Step S105 involves the generation of by-products during mass production. The by-products are solidified in the internal space of the mold assembly 800 at the same time as the molded product, and are solidified in the resin passage. The resin passage includes, for example, a sprue and a runner. The by-products are ejected from the mold assembly 800 together with the molded product by the ejector device 200.

[0114] The amount of by-products generated during mass production is an example of the amount of material loss. The amount of by-products generated can be calculated based on molding conditions. For example, the amount of by-products generated can be calculated as the difference between the weight of the resin filled inside mold device 800 (which can be calculated, for example, from the cross-sectional area of ​​cylinder 310, the forward movement of screw 330, and the density of the resin) and the weight of the molded product. Alternatively, the amount of by-products generated may be calculated based on the volume of the resin passage in mold device 800 and the density of the resin. The calculation of the amount of by-products generated may be performed by the user of injection molding machine 10, the control device 700 of injection molding machine 10, or a management device that manages multiple control devices 700. The amount of by-products generated may also be measured using a weighing scale.

[0115] Step S106 includes the occurrence of defective products during mass production. Defective products are molded products other than non-defective products, and are molded products whose quality does not meet the desired standard. The quality of the molded products is evaluated, for example, by at least one of dimensions, shape, weight, and color. An inspection device inspects the quality of the molded products. The molded products are sorted into non-defective and defective products based on the inspection results.

[0116] The amount of defective products generated during mass production is an example of the amount of material loss. The amount of defective products generated can be calculated based on molding conditions. For example, the amount of defective products generated can be calculated based on the cross-sectional area of ​​cylinder 310, the forward movement of screw 330, the density of the resin, and the weight of by-products. The amount of defective products generated may also be calculated based on the volume of cavity space 801 of mold device 800 and the density of the resin. The calculation of the amount of defective products generated may be performed by the user of injection molding machine 10, the control device 700 of injection molding machine 10, or a management device that manages multiple control devices 700. The amount of defective products generated may also be measured using a weight scale.

[0117] Step S107 includes temporarily suspending mass production. Mass production is temporarily suspended, for example, when there is a malfunction in the injection molding machine 10 or peripheral devices (e.g., a molded product conveying device, a temperature control device for the mold device 800, etc.), or when a molded product is defective. The duration of the temporary suspension is not particularly limited, but is, for example, within 10 minutes. Step S108 includes resuming mass production. Mass production is resumed after the cause of the temporary suspension has been eliminated.

[0118] Step S109 includes the use of waste shots when mass production is restarted. Since the quality of molded products is unstable immediately after mass production is restarted, molded products obtained through waste shots may be treated as defective products. The number of waste shots is set in advance. The amount of waste shots when mass production is restarted is an example of the amount of material loss, and is calculated in the same way as the amount of waste shots when mass production starts.

[0119] Step S110 includes purging when the injection molding machine 10 is shut down. Shutting down the injection molding machine 10 includes lowering the temperature of the cylinder 310. Lowering the temperature of the cylinder 310 includes lowering the temperature of the cylinder 310 to the set temperature during standby. Purging is performed before the temperature of the cylinder 310 starts to decrease, or while the temperature of the cylinder 310 is decreasing. The purging amount during shutdown is an example of the amount of material loss, and is calculated in the same way as the purging amount during shutdown.

[0120] As described above, the amount of material loss refers to the amount of resin injected from the injection molding machine 10 that does not become a molded article (product). Some of the resin that does not become a molded article may be crushed using a crusher or the like and recycled as molding material. Therefore, the amount of material loss does not necessarily coincide with the amount of waste. Therefore, in this embodiment, the amount of waste and the amount of recycled material are managed separately, as described below. Therefore, the amount of waste can be managed accurately.

[0121] By accurately managing the amount of waste, it is possible to accurately calculate, for example, the CO2 emissions of Scope 3, Category 5 as defined in the GHG (Greenhouse Gas) Protocol. Scope 3, Category 5 CO2 emissions are CO2 emissions that can be reduced by reviewing the operation of the injection molding machine 10. It is also possible to accurately calculate the emissions of each greenhouse gas (such as CH4 gas). It is also possible to accurately calculate the total amount obtained by multiplying the emissions of each greenhouse gas by its global warming potential (GWP). The global warming potential is a coefficient that indicates how many times larger the greenhouse effect of a particular gas is than that of CO2.

[0122] Next, an example of the components of the molded product management device 20 will be described with reference to Fig. 4. The molded product management device 20 manages the amount of material loss by dividing it into a waste amount and a recycled amount. The molded product management device 20 may be, for example, the control device 700 of the injection molding machine 10. Alternatively, the molded product management device 20 may be a management device that manages multiple control devices 700. The management device is a host computer of the control devices 700.

[0123] The molded product management device 20 includes electronic circuits such as a CPU, a field programmable gate array (FPGA), or an application specific integrated circuit (ASIC), and performs the various control operations described in this specification by executing instruction codes stored in a memory or by being a circuit designed for a specific application.

[0124] As shown in Fig. 4, the molded product control device 20 includes, for example, a data acquisition unit 21, a data storage unit 22, a calculation unit 23, and a data output unit 24. Note that each functional block shown in Fig. 4 is conceptual and does not necessarily have to be physically configured as shown. All or part of each functional block can be functionally or physically distributed or integrated in any unit.

[0125] As shown in FIG. 5, the data acquisition unit 21 acquires the identification information of each molded product manufactured by the injection molding machine 10 and the amount of material loss per molded product manufactured during a set period, linking them together. The data acquisition unit 21 also acquires the amount of material loss, dividing it into a waste amount and a recycled amount. The data storage unit 22 stores the identification information of each molded product manufactured by the injection molding machine 10 and the amount of material loss per molded product manufactured during a set period, linking them together. The data storage unit 22 also stores the amount of material loss, dividing it into a waste amount and a recycled amount. The calculation unit 23 calculates the amount of CO2 emissions based on the waste amount. The data output unit 24 outputs at least one of the data stored in the data storage unit 22 and the calculation result of the calculation unit 23. The data acquisition unit 21, the data storage unit 22, the calculation unit 23, and the data output unit 24 will be described in detail below.

[0126] The data acquisition unit 21 acquires identification information for each molded product manufactured by the injection molding machine 10 from the control device 700 of the injection molding machine 10 or the like. As shown in FIG. 5, the identification information for the molded product preferably includes identification information for the group to which the molded product belongs, identification information for the lot to which the molded product belongs, and identification information for the shot of the molded product. The group to which the molded product belongs is divided, for example, according to a production plan or the period from start-up to shut-down of the injection molding machine 10. The identification information for the shot includes, for example, at least one of the date and time of the shot and the number.

[0127] The data acquisition unit 21 acquires the amount of material loss per molded product manufactured during a set period, dividing it into the amount of waste and the amount of recycling. By managing the amount of material loss separately, the amount of waste can be accurately managed. As a result, for example, CO2 emissions in Category 5 of Scope 3 as defined in the GHG (Greenhouse Gas) Protocol can be accurately calculated.

[0128] As shown in FIG. 6, the set period is determined for each factor. In FIG. 6, "◯" indicates that it can be used as the set period. The set period is determined using the operation device 750 or the input device 32. The operation device 750 is a part of the injection molding machine 10, while the input device 32 is provided separately from the injection molding machine 10. In FIG. 5, set period 1 is used as the set period for factors 1 to 3, and set period 3 is used as the set period for factor 4.

[0129] The amount of material loss, waste, or recycling per molded product can be obtained by dividing the amount of material loss, waste, or recycling that occurred during a set period by the number of molded products manufactured during that period. Here, molded products include only good products and do not necessarily include defective products.

[0130] The set period 1 is the period from the start of execution of the molded product production plan to the end of execution. The set period 1 may be the period from the start of execution of the injection molding machine 10 to the end of execution. Note that the injection molding machine 10 may be started up and shut down multiple times from the start of execution of the molded product production plan to the end of execution.

[0131] Set period 2 is a period for producing lots consisting of multiple molded products. The number of molded products that make up one lot is determined in advance in the production plan. The number of molded products that make up one lot is less than the planned production number. Note that multiple lots may be produced between the start-up and shutdown of the injection molding machine 10.

[0132] The set period 3 is the period for manufacturing an individual molded product, that is, the period for one shot.

[0133] The set period is determined in advance, but may be changeable using the operation device 750 or input device 32 of the injection molding machine 10. To make the set period changeable, the identification information of the molded product preferably includes identification information of the group to which the molded product belongs, identification information of the lot to which the molded product belongs, and identification information of the shot of the molded product, as shown in FIG.

[0134] The data acquisition unit 21 may acquire the amount of material loss divided into the amount of waste and the amount of recycling according to the cause of the material loss. The amount of waste and the amount of recycling can be managed by cause, and the factors that need to be resolved to reduce the amount of waste can be identified. Furthermore, managing the amount of waste and the amount of recycling by cause makes it easier to revise the amount of waste and the amount of recycling when something originally planned to be discarded is later recycled. This is because recycling something originally planned to be discarded later occurs for each cause. For example, resin lumps generated during purging are larger in size and more difficult to crush than defective molded products and by-products. However, improvements to the crusher 33 may make it possible to crush the resin lumps generated during purging.

[0135] The amount of material loss, waste or recycled is measured by a weighing scale 31. Alternatively, the amount of material loss, waste or recycled is calculated by a user of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages a plurality of control devices 700. The user of the injection molding machine 10 calculates the amount of material loss, waste or recycled and inputs the calculation result into the operation device 750. The input device 32 may be used instead of the operation device 750.

[0136] The data acquisition unit 21 acquires the amount of material loss, waste, or recycled amount from the weight scale 31. Alternatively, the data acquisition unit 21 may acquire the amount of material loss, waste, or recycled amount from the operation device 750 of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages multiple control devices 700. The data acquisition unit 21 may acquire the recycled amount from the crusher 33. The recycled amount can be estimated from the operating time of the crusher 33, etc. The discard amount can also be calculated as the difference between the amount of material loss and the recycled amount.

[0137] As shown in Fig. 5, the data storage unit 22 stores the identification information of each molded product manufactured by the injection molding machine 10 in association with the amount of material loss acquired by the data acquisition unit 21. As shown in Fig. 5, the data storage unit 22 may directly link the identification information and the amount of material loss in a single list. However, the data storage unit 22 may include a first storage unit that stores the identification information and a second storage unit that stores the amount of material loss, and may further include a third storage unit that stores information that links the identification information stored in the first storage unit with the amount of material loss stored in the second storage unit.

[0138] The data storage unit 22 also stores the amount of material loss per molded product manufactured during a set period, separated into the amount of waste and the amount of recycling. By managing the amount of material loss separately, the amount of waste can be accurately managed. As a result, for example, CO2 emissions in Category 5 of Scope 3 as defined in the GHG (Greenhouse Gas) Protocol can be accurately calculated.

[0139] Furthermore, the data storage unit 22 may store the amount of material loss divided into the amount of waste and the amount of recycling according to the cause of the amount of material loss. The amount of waste and the amount of recycling can be managed according to the cause, and the cause that needs to be resolved when reducing the amount of waste can be identified. Furthermore, if the amount of waste and the amount of recycling are managed according to the cause, it is easy to revise the amount of waste and the amount of recycling when something that was originally planned to be discarded is later recycled. This is because something that was originally planned to be discarded is later recycled for each cause.

[0140] The calculation unit 23 calculates the amount of CO2 emissions based on the amount of waste stored in the data storage unit 22. For example, the calculation unit 23 calculates the CO2 emissions of Category 5 of Scope 3 defined in the GHG (Greenhouse Gas) Protocol. The calculation unit 23 can also calculate the amount of emissions of each greenhouse gas (e.g., CH4 gas). The calculation unit 23 can also calculate the total amount of emissions of each greenhouse gas multiplied by its global warming potential (GWP).

[0141] The calculation unit 23 calculates the amount of CO2 emissions, for example, by multiplying the amount of waste by the amount of CO2 emissions per unit amount of waste. The amount of CO2 emissions per unit amount of waste is determined in advance based on past performance, etc., and is stored in advance in the data storage unit 22. The amount of CO2 emissions per unit amount of waste may be obtained from the resin manufacturer. Examples of acquisition means include the Internet and an input device that allows the user to input a numerical value. The amount of CO2 emissions per unit amount of waste may be prepared for each resin composition.

[0142] The molded product management device 20 may manage resin composition information, molded product identification information, the amount of material loss, the amount of waste, and the amount of recycled material in association with each other. The resin composition information can be acquired from the operation device 750 of the injection molding machine 10, the control device 700 of the injection molding machine 10, or a management device that manages multiple control devices 700. The input device 32 may be used instead of the operation device 750.

[0143] The calculation unit 23 may calculate the amount of CO2 emissions equivalent to the total amount of waste per molded product, or may calculate the amount of CO2 emissions for each factor that generates the amount of waste. This makes it possible to grasp the amount of CO2 emissions that can be reduced by solving each factor. In addition, recycling of items that were originally scheduled to be discarded at a later date occurs for each factor.

[0144] The data output unit 24 outputs at least one of the data stored in the data storage unit 22 and the calculation result of the calculation unit 23. As the output device, for example, a display device 760 is used. That is, the data stored in the data storage unit 22 and the calculation result of the calculation unit 23 may be displayed on the screen of the display device 760. Note that as the output device, a display device provided separately from the injection molding machine 10 or a printing device 41 may also be used.

[0145] Although the embodiment of the molded product management device according to the present invention has been described above, the present invention is not limited to the above embodiment. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Naturally, these also fall within the technical scope of the present invention. [Explanation of symbols]

[0146] 20 Molded product management device 21 Data Acquisition Section 22 Data storage unit 23 Calculation section 24 Data output section

Claims

1. a data storage unit that stores identification information of each molded product manufactured by the injection molding machine and the amount of material loss per molded product manufactured during a set period in association with each other; the amount of material loss is the amount of resin that is not used to make the molded product out of the amount of resin injected from the injection molding machine during the set period, The data storage unit stores the amount of material loss divided into a discarded amount and a recycled amount.

2. 2. The molded product management device according to claim 1, wherein the data storage unit stores the amount of material loss divided into the amount of waste and the amount of recycled material according to the cause of the amount of material loss.

3. The molded product management device according to claim 2 , wherein the set period is determined for each of the factors.

4. 4. The molded product management device according to claim 3, wherein the set period is a period from the start to the end of execution of a production plan for the molded products, a period from the start to the shut-down of the injection molding machine, a period for producing a lot consisting of a plurality of molded products, or a period for producing each of the molded products.

5. Based on the waste amount stored in the data storage unit, ２ The molded product management device according to any one of claims 1 to 4, further comprising a calculation unit for calculating a discharge amount.

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