CN117984526A

CN117984526A - Control device for injection molding machine and display device for injection molding machine

Info

Publication number: CN117984526A
Application number: CN202311186051.3A
Authority: CN
Inventors: 堤雄贵; 远藤博一
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2022-11-02
Filing date: 2023-09-13
Publication date: 2024-05-07
Also published as: JP2024066919A; DE102023130272A1

Abstract

A control device for an injection molding machine and a display device for an injection molding machine reduce the occurrence of defective products by monitoring the gas burning of molded products. The control device for an injection molding machine according to one embodiment includes: an acquisition unit configured to acquire information indicating pressure from a detection unit provided in a cavity space in a mold device of an injection molding machine in the vicinity of an end where a molding material filled in the cavity space reaches; and a control unit configured to determine whether or not gas burn occurs in the molded article produced by the injection molding machine, and predict or display a period until gas burn occurs in the molded article, based on a predetermined condition related to pressure detected at a time point near the time of switching from the filling step to the holding step of the injection molding machine or near the time when the molding material is filled to the end.

Description

Control device for injection molding machine and display device for injection molding machine

The present application claims priority based on japanese patent application No. 2022-1768720, filed on day 2, 11 in 2022. The entire contents of this japanese application are incorporated by reference into the present specification.

Technical Field

The present invention relates to a control device for an injection molding machine and a display device for an injection molding machine.

Background

Conventionally, there is a technique for monitoring a state when a molding material is filled in an injection process. For example, patent document 1 describes a technique for detecting a filling pressure and controlling the rotational speed of a screw according to the rate of change of the pressure. Thus, injection molding can be performed in a state where the flow resistance of the molding material is appropriate.

In an injection molding machine, a molded article is produced by flowing a molding material into a cavity space inside a mold device. The cavity space is formed on the parting surface of the fixed die and the movable die. When the molding material flows into the cavity space, the gas existing in the cavity space escapes to the outside through the parting surface. Thereby, the cavity space can be filled with the molding material. If the injection molding is repeated, components of the molding material are gradually deposited on the parting surface, and therefore, it is difficult for the gas to be discharged to the outside of the cavity space. At this time, the gas not discharged is compressed adiabatically and becomes high temperature, and there is a possibility that gas burning occurs in the molded product.

Patent document 1: japanese patent laid-open No. 03-030926

However, patent document 1 is not a technique for monitoring gas burn occurring in a molded article due to repeated injection molding, but a technique for controlling the rotational speed of a screw based on a detected filling pressure.

Disclosure of Invention

One embodiment of the present invention provides a technique for reducing the occurrence of defective products by performing monitoring related to gas burning of molded products.

The control device for an injection molding machine according to one embodiment of the present invention includes: an acquisition unit configured to acquire information indicating pressure from a detection unit provided in a cavity space in a mold device of an injection molding machine in the vicinity of an end where a molding material filled in the cavity space reaches; and a control unit configured to determine whether or not gas burn occurs in the molded article produced by the injection molding machine, and predict or display a period until gas burn occurs in the molded article, based on a predetermined condition related to pressure detected at a time point near the time of switching from the filling step to the holding step of the injection molding machine or near the time when the molding material is filled to the end.

Effects of the invention

According to one embodiment of the present invention, the occurrence of defective products is reduced by performing monitoring related to gas burning of molded products.

Drawings

Fig. 1 is a diagram showing a state at the end of mold opening of an injection molding machine according to one embodiment.

Fig. 2 is a diagram showing a state at the time of mold closing of the injection molding machine according to the embodiment.

Fig. 3 is a diagram showing constituent elements of a control device for an injection molding machine according to embodiment 1, with functional blocks.

Fig. 4 is a diagram showing a molding material flowing into the mold device according to embodiment 1 and a sensor provided in the mold device.

Fig. 5 is a diagram showing a change in the flow of molding material in the mold device according to embodiment 1.

Fig. 6 is a diagram showing changes in temperature and pressure from the start of filling to the holding pressure in the mold device according to embodiment 1.

Fig. 7 is a diagram illustrating a change in pressure detected by a sensor when the mold device according to embodiment 1 is in a filled state.

Fig. 8 is a diagram illustrating a change in pressure detected by a sensor at the time of V/P switching in the die apparatus according to embodiment 1.

Fig. 9 is a diagram illustrating a log information screen outputted by the display control unit according to embodiment 1.

Fig. 10 is a flowchart showing a processing procedure before gas burn is detected in the injection molding machine according to embodiment 1.

Fig. 11 is a diagram illustrating a screen of the air burn prediction information outputted by the display control unit according to embodiment 2.

Fig. 12 is a flowchart showing a processing procedure before an alarm is output in the control device according to embodiment 2.

In the figure: 10-injection molding machine, 700-control device, 701-CPU, 711-setting section, 712-acquisition section, 713-determination section, 714-log control section, 715-display control section, 702-storage medium, 721-log storage section.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are not limited to the embodiments of the invention, but are merely examples, and all the features and combinations described in the embodiments are not necessarily essential to the invention. In the drawings, the same or corresponding structures may be denoted by the same or corresponding symbols, and description thereof may be omitted.

Fig. 1 is a diagram showing a state at the end of mold opening of the injection molding machine according to embodiment 1. Fig. 2 is a diagram showing a state at the time of mold closing of the injection molding machine according to embodiment 1. In the present specification, the X-axis direction, the Y-axis direction, and the Z-axis direction are directions perpendicular to each other. The X-axis direction and the Y-axis direction represent horizontal directions, and the Z-axis direction represents vertical directions. When the mold clamping device 100 is horizontal, 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 in the Y-axis direction is referred to as the operation side, and the positive side in the Y-axis direction is referred to as the opposite side to the operation side.

As shown in fig. 1 to 2, the injection molding machine 10 includes: a mold clamping device 100 for opening and closing the mold device 800; an ejector 200 for ejecting the molded article molded by the mold device 800; an injection device 300 injecting a molding material to the mold device 800; a moving device 400 for advancing and retreating the injection device 300 with respect to the mold device 800; a control device 700 for controlling the respective constituent elements of the injection molding machine 10; and a frame 900 for supporting the components of the injection molding machine 10. The frame 900 includes a clamping device frame 910 that supports the clamping device 100 and an injection device frame 920 that supports the injection device 300. The mold clamping device frame 910 and the injection device frame 920 are respectively provided on the bottom plate 2 via horizontal adjustment casters 930. The control device 700 is disposed in the internal space of the injection device frame 920. The following describes the respective constituent elements of the injection molding machine 10.

(Mold clamping device)

In the description of the mold clamping apparatus 100, the moving direction (for example, the positive X-axis direction) of the movable platen 120 during mold closing is set to the front, and the moving direction (for example, the negative X-axis direction) of the movable platen 120 during mold opening is set to the rear.

The mold clamping device 100 performs mold closing, pressure increasing, mold clamping, pressure releasing, and mold opening of the mold device 800. The mold apparatus 800 includes a stationary mold 810 and a movable mold 820. The mold clamping device 100 is, for example, horizontal, and the mold opening/closing direction is horizontal. The mold clamping device 100 includes 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 moving mechanism 102 that moves the movable platen 120 relative to the fixed platen 110 in a mold opening/closing direction.

The stationary platen 110 is fixed relative to the clamp frame 910. A stationary mold 810 is mounted on a surface of the stationary platen 110 opposite to the movable platen 120.

The movable platen 120 is disposed so as to be movable in the mold opening/closing direction with respect to the mold clamping device frame 910. A guide 101 for guiding the movable platen 120 is laid on the mold clamping device frame 910. A movable mold 820 is mounted on a surface of the movable platen 120 facing the fixed platen 110.

The moving mechanism 102 performs mold closing, pressure increasing, mold closing, pressure releasing, and mold opening of the mold apparatus 800 by advancing and retracting the movable platen 120 relative to the fixed platen 110. The moving mechanism 102 includes a toggle base 130 disposed at a distance from the fixed platen 110, a link 140 connecting the fixed platen 110 and the toggle base 130, a toggle mechanism 150 moving the movable platen 120 relative to the toggle base 130 in the mold opening/closing direction, a mold clamping motor 160 operating the toggle mechanism 150, a motion conversion mechanism 170 converting the rotational motion of the mold clamping motor 160 into a linear motion, and a mold thickness adjustment mechanism 180 adjusting the distance between the fixed platen 110 and the toggle base 130.

The toggle seat 130 is disposed at a distance from the fixed platen 110, and is mounted on the clamping device frame 910 so as to be movable in the mold opening/closing direction. The toggle mount 130 may be configured to be movable along a guide provided on the clamp frame 910. The guide of the toggle seat 130 may be common to the guide 101 of the movable platen 120.

In the present embodiment, the stationary platen 110 is fixed to the clamping device frame 910, and the toggle mount 130 is disposed so as to be movable in the mold opening and closing direction with respect to the clamping device frame 910, but the toggle mount 130 may be fixed to the clamping device frame 910, and the stationary platen 110 may be disposed so as to be movable in the mold opening and closing direction with respect to the clamping device frame 910.

The connecting rod 140 connects the fixed platen 110 and the toggle base 130 with a space L therebetween in the mold opening and closing direction. Multiple (e.g., 4) connecting rods 140 may be used. The plurality of tie bars 140 are arranged parallel to the mold opening and closing direction and extend according to the mold clamping force. A link strain detector 141 detecting strain of the link 140 may be provided on at least 1 link 140. The link strain detector 141 transmits a signal indicating the detection result to the control device 700. The detection result of the tie bar strain detector 141 is used for detection of the clamping force or the like.

In the present embodiment, the tie bar strain detector 141 is used as a mold clamping force detector for detecting a mold clamping force, but the present invention is not limited thereto. The mold clamping force detector is not limited to the strain gauge type, but may be a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and the mounting position thereof is not limited to the tie bar 140.

The toggle mechanism 150 is disposed between the movable platen 120 and the toggle base 130, and moves the movable platen 120 with respect to the toggle base 130 in the mold opening and closing direction. The toggle mechanism 150 has a crosshead 151 that moves in the mold opening and closing direction, and a pair of link groups that are bent and extended by the movement of the crosshead 151. The pair of link groups includes a1 st link 152 and a 2 nd link 153, which are connected to each other by a pin or the like so as to be freely bendable. The 1 st link 152 is attached to the movable platen 120 by a pin or the like so as to be swingable. The 2 nd link 153 is attached to the toggle base 130 by a pin or the like so as to be swingable. The 2 nd link 153 is attached to the crosshead 151 via the 3 rd link 154. When the crosshead 151 is advanced and retracted relative to the toggle mount 130, the 1 st link 152 and the 2 nd link 153 are extended and retracted to advance and retract the movable platen 120 relative to the toggle mount 130.

The structure of the toggle mechanism 150 is not limited to the structure shown in fig. 1 and 2. For example, in fig. 1 and 2, the number of nodes of each link group is 5, but may be 4, or one end of the 3 rd link 154 may be connected to the node of the 1 st link 152 and the 2 nd link 153.

The clamp motor 160 is mounted to the toggle mount 130 and operates the toggle mechanism 150. The clamp motor 160 advances and retreats the crosshead 151 with respect to the toggle mount 130, and stretches the 1 st link 152 and the 2 nd link 153 to advance and retreat the movable platen 120 with respect to the toggle mount 130. The mold clamping motor 160 is directly connected to the motion conversion mechanism 170, but may be connected to the motion conversion mechanism 170 via a belt, pulley, or the like.

The motion conversion mechanism 170 converts the rotational motion of the clamp motor 160 into a linear motion of the crosshead 151. The motion conversion mechanism 170 includes a screw shaft and a screw nut screwed with the screw shaft. Balls or rollers may be interposed between the screw shaft and the screw nut.

The mold clamping device 100 performs a mold closing process, a pressure increasing process, a mold clamping process, a pressure releasing process, a mold opening process, and the like under the control of the control device 700.

In the mold closing step, the movable platen 120 is advanced by driving the mold clamping motor 160 to advance the crosshead 151 to the mold closing end position at a set movement speed so that the movable mold 820 is brought into contact with the fixed mold 810. For example, the position and the moving speed of the crosshead 151 are detected using a clamp motor encoder 161 or the like. The clamp motor encoder 161 detects the rotation of the clamp motor 160, and transmits a signal indicating the detection result to the control device 700.

The crosshead position detector for detecting the position of the crosshead 151 and the crosshead moving speed detector for detecting the moving speed of the crosshead 151 are not limited to the clamp motor encoder 161, and a conventional detector may be used. The movable platen position detector for detecting the position of the movable platen 120 and the movable platen moving speed detector for detecting the moving speed of the movable platen 120 are not limited to the mold clamping motor encoder 161, and a conventional detector may be used.

In the pressure increasing step, the clamping motor 160 is further driven to further advance the crosshead 151 from the mold closing end position to the clamping position, thereby generating clamping force.

In the mold clamping step, the mold clamping motor 160 is driven to maintain the position of the crosshead 151 at the mold clamping position. In the mold clamping step, the mold clamping force generated in the pressure increasing step is maintained. In the mold clamping step, 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 a liquid molding material. The filled molding material is cured, thereby obtaining a molded article.

The number of cavity spaces 801 may be 1 or more. In the latter case, a plurality of molded articles can be obtained at the same time. An insert may be disposed in a portion of the cavity space 801 and another portion of the cavity space 801 may be filled with molding material. A molded article in which the insert and the molding material are integrated can be obtained.

In the decompression step, the clamping motor 160 is driven to retract the crosshead 151 from the clamping position to the mold opening start position, and the movable platen 120 is retracted to reduce the clamping force. The mold opening start position and the mold closing end position may be the same position.

In the mold opening step, the movable platen 120 is retracted by driving the mold clamping motor 160 to retract the crosshead 151 from the mold opening start position to the mold opening end position at a set movement speed, so that the movable mold 820 is separated from the fixed mold 810. Then, the ejector 200 ejects the molded article from the movable mold 820.

The setting conditions in the mold closing step, the pressure increasing step, and the mold closing step are set in a unified manner as a series of setting conditions. For example, the moving speed, the position (including the mold closing start position, the moving speed switching position, the mold closing end position, and the mold clamping position) and the mold clamping force of the crosshead 151 in the mold closing step and the pressure increasing step are set in a unified manner as a series of setting conditions. The mold closing start position, the moving speed switching position, the mold closing end position, and the mold closing position are arranged in this order from the rear side to the front side, and indicate the start point and the end point of the section in which the moving speed is set. The movement speed is set for each section. The number of the movement speed switching positions may be 1 or plural. The moving speed switching position may not be set. Only one of the mold clamping position and the mold clamping force may be set.

The conditions for setting in the decompression step and the mold opening step are set in the same manner. For example, the moving speed and the position (the mold opening start position, the moving speed switching position, and the mold opening end position) of the crosshead 151 in the decompression step and the mold opening step are set in a unified manner as a series of setting conditions. The mold opening start position, the movement speed switching position, and the mold opening end position are arranged in this order from the front side to the rear side, and indicate the start point and the end point of the section in which the movement speed is set. The movement speed is set for each section. The number of the movement speed switching positions may be 1 or plural. The moving speed switching position may not be set. The mold opening start position and the mold closing end position may be the same position. The mold opening end position and the mold closing start position may be the same position.

In addition, instead of the moving speed, position, etc. of the crosshead 151, the moving speed, position, etc. of the movable platen 120 may be set. In addition, the clamping force may be set instead of the position of the crosshead (for example, the clamping position) and the position of the movable platen.

However, the toggle mechanism 150 amplifies the driving force of the clamp motor 160 and transmits it to the movable platen 120. Its magnification is also called toggle magnification. The toggle magnification changes according to an angle θ (hereinafter, also referred to as "link angle θ") formed by the 1 st link 152 and the 2 nd link 153. The link angle θ is obtained from the position of the crosshead 151. When the link angle θ is 180 °, the toggle magnification becomes maximum.

When the thickness of the mold device 800 changes due to replacement of the mold device 800, temperature change of the mold device 800, or the like, mold thickness adjustment is performed to obtain a predetermined clamping force at the time of clamping. In the die thickness adjustment, for example, the interval L between the fixed platen 110 and the toggle base 130 is adjusted so that the link angle θ of the toggle mechanism 150 becomes a predetermined angle at the time of die contact of the movable die 820 with the fixed die 810.

The mold clamping device 100 has a mold thickness adjusting mechanism 180. The die thickness adjustment mechanism 180 adjusts the distance L between the fixed platen 110 and the toggle base 130, thereby performing die thickness adjustment. The timing of the mold thickness adjustment is performed, for example, during a period from the end of the molding cycle to the start of the next molding cycle. The die thickness adjusting mechanism 180 includes, for example: a screw shaft 181 formed at a rear end portion of the connection rod 140; a screw nut 182 rotatably held in the toggle seat 130 and being non-retractable; and a die thickness adjusting motor 183 for rotating a screw nut 182 screwed to the screw shaft 181.

A screw shaft 181 and a screw nut 182 are provided for each of the connection rods 140. The rotational driving force of the die thickness adjusting motor 183 may be transmitted to the plurality of lead screw nuts 182 via the rotational driving force transmitting portion 185. A plurality of lead screw nuts 182 can be rotated synchronously. Further, by changing the transmission path of the rotational driving force transmission unit 185, the plurality of lead screw nuts 182 can be rotated individually.

The rotational driving force transmitting portion 185 is constituted by a gear or the like, for example. At this time, driven gears are formed on the outer periphery of each screw nut 182, a driving gear is mounted on the output shaft of the die thickness adjusting motor 183, and an intermediate gear engaged with the driven gears and the driving gear is rotatably held at the center portion of the toggle seat 130. In addition, the rotational driving force transmitting portion 185 may be formed of a belt, a pulley, or the like instead of the gear.

The operation of the die thickness adjusting mechanism 180 is controlled by the control device 700. The control device 700 drives the die thickness adjustment motor 183 to rotate the lead screw nut 182. As a result, the position of the toggle housing 130 relative to the connecting rod 140 is adjusted, and the interval L between the fixed platen 110 and the toggle housing 130 is adjusted. In addition, a plurality of die thickness adjusting mechanisms may be used in combination.

The interval L is detected using a die thickness adjustment motor encoder 184. The die thickness adjustment motor encoder 184 detects the rotation amount and rotation direction of the die thickness adjustment motor 183, and transmits a signal indicating the detection result to the control device 700. The detection result of the die thickness adjustment motor encoder 184 is used for monitoring and controlling the position and the interval L of the toggle seat 130. The toggle seat position detector for detecting the position of the toggle seat 130 and the interval detector for detecting the interval L are not limited to the die thickness adjusting motor encoder 184, and a conventional detector may be used.

The mold clamping device 100 may have a mold temperature regulator that regulates the temperature of the mold device 800. The die device 800 has a flow path for the temperature control medium therein. The mold temperature regulator regulates the temperature of the temperature regulating medium supplied to the flow path of the mold device 800, thereby regulating the temperature of the mold device 800.

The mold clamping device 100 of the present embodiment is a horizontal mold opening/closing direction, but may be a vertical mold opening/closing direction.

The mold clamping device 100 of the present embodiment includes the mold clamping motor 160 as a driving source, but may include a hydraulic cylinder instead of the mold clamping motor 160. The mold clamping device 100 may include a linear motor for mold opening and closing, or may include an electromagnet for mold clamping.

(Ejector device)

In the description of the ejector 200, the moving direction (for example, the positive X-axis direction) of the movable platen 120 during mold closing is set to the front, and the moving direction (for example, the negative X-axis direction) of the movable platen 120 during mold opening is set to the rear, similarly to the description of the mold clamping device 100 and the like.

The ejector 200 is attached to the movable platen 120 and advances and retreats together with the movable platen 120. The ejector 200 includes: an ejector rod 210 ejecting the molded article from the mold device 800; and a driving mechanism 220 for moving the ejector rod 210 in the moving direction (X-axis direction) of the movable platen 120.

The ejector rod 210 is disposed so as to be movable in and out of the through hole of the movable platen 120. The front end of the ejector rod 210 contacts the ejector plate 826 of the movable mold 820. The tip end of the ejector rod 210 may or may not be connected to the ejector plate 826.

The driving mechanism 220 includes, for example, an ejector motor and a motion conversion mechanism that converts rotational motion of the ejector motor into linear motion of the ejector rod 210. The motion conversion mechanism comprises a screw shaft and a screw nut screwed with the screw shaft. Balls or rollers may be interposed between the screw shaft and the screw nut.

The ejector 200 performs the ejection process under the control of the control device 700. In the ejection step, the ejector rod 210 is advanced from the standby position to the ejection position at a set movement speed, and the ejector plate 826 is advanced to eject the molded article. Then, the ejector motor is driven to retract the ejector rod 210 at a set movement speed, and the ejector plate 826 is retracted to the original standby position.

The position and moving speed of the ejector rod 210 are detected, for example, using an ejector motor encoder. The ejector motor encoder detects the rotation of the ejector motor and transmits a signal indicating the detection result to the control device 700. 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 a conventional detector may be used.

(Injection device)

In the description of the injection device 300, the direction of movement of the screw 330 (for example, the negative X-axis direction) during filling is set to the front, and the direction of movement of the screw 330 (for example, the positive X-axis direction) during metering is set to the rear, unlike the description of the mold clamping device 100 and the description of the ejector 200.

The injection device 300 is provided on the slide base 301, and the slide base 301 is disposed so as to be movable relative to the injection device frame 920. The injection device 300 is disposed so as to be movable in and out of the mold device 800. The injection device 300 is in contact with the mold device 800, and fills the cavity space 801 in the mold device 800 with the molding material measured in the cylinder 310. The injection device 300 includes, for example, a cylinder 310 for heating a molding material, a nozzle 320 provided at a distal end portion of the cylinder 310, a screw 330 rotatably disposed in the cylinder 310, a metering motor 340 for rotating the screw 330, an injection motor 350 for advancing and retreating the screw 330, and a load detector 360 for detecting a load transmitted between the injection motor 350 and the screw 330.

The cylinder 310 heats the molding material supplied from the supply port 311 to the inside. The molding material includes, for example, a resin or the like. The molding material is formed into, for example, a pellet shape, and is supplied in a solid state to the supply port 311. The supply port 311 is formed at the rear of the cylinder 310. A cooler 312 such as a water-cooled cylinder is provided on the outer periphery of the rear portion of the cylinder block 310. A heater 313 such as a belt heater and a temperature detector 314 are provided on the outer periphery of the cylinder 310 in front of the cooler 312.

The cylinder 310 is divided into a plurality of regions along an axial direction (e.g., an X-axis direction) of the cylinder 310. The heater 313 and the temperature detector 314 are provided in each of the plurality of regions. The control device 700 controls the heater 313 so that the temperature detected by the temperature detector 314 becomes the set temperature.

The nozzle 320 is provided at the front end of the cylinder 310, and presses the die device 800. A heater 313 and a temperature detector 314 are provided on the outer periphery of the nozzle 320. The control device 700 controls the heater 313 so that the detected temperature of the nozzle 320 becomes the set temperature.

The screw 330 is rotatably disposed in the cylinder 310 and is movable forward and backward. When the screw 330 is rotated, the molding material is conveyed forward along the spiral groove of the screw 330. The molding material is gradually melted by heat from the cylinder 310 while being conveyed forward. As the molding material in the liquid state is conveyed to the front of the screw 330 and accumulated in the front of the cylinder 310, the screw 330 is retracted. Then, when the screw 330 is advanced, the liquid molding material accumulated in front of the screw 330 is injected from the nozzle 320 and filled in the mold device 800.

The check ring 331 is attached to the front of the screw 330 so as to be movable forward and backward, and the check ring 331 serves as a check valve to prevent the molding material from flowing backward from the front of the screw 330 when the screw 330 is pushed forward.

When the screw 330 is advanced, the check ring 331 is pushed rearward by the pressure of the molding material in front of the screw 330, and retreats relatively to the screw 330 to a closed position (see fig. 2) blocking the flow path of the molding material. This prevents the molding material accumulated in front of the screw 330 from flowing backward.

On the other hand, when the screw 330 is rotated, the check ring 331 is pushed forward by the pressure of the molding material conveyed forward along the spiral groove of the screw 330, and relatively advances to an open position (refer to fig. 1) for opening the flow path of the molding material with respect to the screw 330. Thereby, the molding material is conveyed to the front of the screw 330.

Check ring 331 may be either a co-rotating type that rotates with screw 330 or a non-co-rotating type that does not rotate with screw 330.

In addition, the injection device 300 may have a driving source that advances and retreats the check ring 331 with respect to the screw 330 between the open position and the closed position.

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

Injection motor 350 advances and retracts screw 330. A motion conversion mechanism or the like for converting the rotational motion of injection motor 350 into the linear motion of screw 330 is provided between injection motor 350 and screw 330. The motion conversion mechanism includes, for example, a screw shaft and a screw nut screwed to the screw shaft. Balls, rollers, etc. may be provided between the screw shaft and the screw nut. The driving source for advancing and retreating the screw 330 is not limited to the injection motor 350, and may be, for example, a hydraulic cylinder or the like.

The load detector 360 detects a 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 in a transmission path of the load between the injection motor 350 and the screw 330, and detects the load acting on the load detector 360.

The load detector 360 transmits a signal of the detected load to the control device 700. The load detected by the load detector 360 is converted into a pressure acting between the screw 330 and the molding material, and is used for controlling and monitoring the back pressure of the screw 330 and the pressure acting on the molding material from the screw 330, etc. by the pressure received by the screw 330 from the molding material.

The pressure detector for detecting the pressure of the molding material is not limited to the load detector 360, and a conventional detector can be used. For example, a nozzle pressure sensor or an in-mold pressure sensor may be used. The nozzle pressure sensor is provided to the nozzle 320. The mold internal pressure sensor is provided inside the mold device 800.

The injection device 300 performs a metering process, a filling process, a pressure maintaining process, and the like under the control of the control device 700. The filling step and the pressure maintaining step may be collectively referred to as an injection step.

In the metering step, the metering motor 340 is driven to rotate the screw 330 at a set rotational speed, and the molding material is conveyed forward along the spiral groove of the screw 330. Thereby, the molding material is gradually melted. As the molding material in the liquid state is conveyed to the front of the screw 330 and accumulated in the front of the cylinder 310, the screw 330 is retracted. The rotational speed of 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 transmits a signal indicating the detection result to the control device 700. The screw rotation speed detector for detecting the rotation speed of the screw 330 is not limited to the metering motor encoder 341, and a conventional detector can be used.

In the metering step, injection motor 350 may be driven to apply a set back pressure to screw 330 in order to limit rapid retraction of screw 330. The back pressure on the screw 330 is detected, for example, using a load detector 360. When the screw 330 is retracted to the metering end position and a predetermined amount of molding material is accumulated in front of the screw 330, the metering process ends.

The position and rotation speed of the screw 330 in the metering step are set uniformly as a series of setting conditions. For example, a measurement start position, a rotation speed switching position, and a measurement end position are set. These positions are arranged in order from the front side to the rear side, and indicate the start point and the end point of the section in which the rotational speed is set. The rotational speed is set for each section. The number of rotational speed switching positions may be 1 or a plurality of rotational speed switching positions. The rotational speed switching position may not be set. Back pressure is set for each section.

In the filling step, the injection motor 350 is driven to advance the screw 330 at a set moving speed, and the cavity space 801 in the mold apparatus 800 is filled with the liquid molding material stored in front of the screw 330. The position and moving speed of the screw 330 are detected, for example, using the injection motor encoder 351. The injection motor encoder 351 detects the rotation of the injection motor 350 and transmits a signal indicating the detection result thereof to the control device 700. When the position of the screw 330 reaches the set position, the filling process is switched to the pressure maintaining process (so-called V/P switching). The position where the V/P switch is performed is also referred to as a V/P switch position. The set moving speed of the screw 330 may be changed according to the position, time, etc. of the screw 330.

The position and the moving speed of the screw 330 in the filling process are set uniformly as a series of setting conditions. For example, a filling start position (also referred to as an "injection start position"), a moving speed switching position, and a V/P switching position are set. These positions are arranged in this order from the rear side to the front side, and indicate the start point and the end point of the section in which the movement speed is set. The movement speed is set for each section. The number of the movement speed switching positions may be 1 or plural. The moving speed switching position may not be set.

The upper limit value of the pressure of the screw 330 is set for each section in which the moving 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 below the set pressure, the screw 330 advances at the set moving 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 becomes equal to or lower than the set pressure in order to protect the mold.

In the filling step, after the position of the screw 330 reaches the V/P switching position, the screw 330 may be suspended at the V/P switching position and then V/P switching may be performed. Instead of stopping the screw 330, the screw 330 may be advanced at a slight speed or retracted at a slight speed immediately before the V/P switching. The screw position detector for detecting the position of the screw 330 and the screw movement speed detector for detecting the movement speed of the screw 330 are not limited to the injection motor encoder 351, and a conventional detector may be used.

In the pressure maintaining step, the injection motor 350 is driven to push the screw 330 forward, and the pressure of the molding material at the tip end portion of the screw 330 (hereinafter, also referred to as "holding pressure") is maintained at a set pressure, so that the molding material remaining in the cylinder 310 is pushed to the mold device 800. An insufficient amount of molding material due to cooling shrinkage in the mold device 800 can be replenished. The holding pressure is detected, for example, using a load detector 360. The set value of the holding pressure may be changed according to the elapsed time from the start of the pressure-maintaining process. The holding pressure and the holding time for holding the holding pressure in the plurality of holding pressure steps may be set individually or may be set collectively as a series of setting conditions.

In the pressure maintaining step, the molding material in the cavity space 801 in the mold device 800 is gradually cooled, and at the end of the pressure maintaining step, the inlet of the cavity space 801 is blocked by the solidified molding material. This state is called gate sealing, and prevents backflow of molding material from the cavity space 801. After the pressure maintaining process, a cooling process is started. In the cooling step, solidification of the molding material in the cavity space 801 is performed. The metering step may be performed in the cooling step in order to shorten the molding cycle time.

The injection device 300 of the present embodiment is of a coaxial screw type, but may be of a pre-molding type or the like. The injection device of the pre-molding method supplies the molding material melted in the plasticizing cylinder to the injection cylinder, and injects the molding material from the injection cylinder into the mold device. In the plasticizing cylinder, the screw is rotatably disposed so as not to advance and retreat, or the screw is rotatably disposed so as to advance and retreat. On the other hand, in the injection cylinder, the plunger is disposed so as to be movable forward and backward.

The injection device 300 of the present embodiment is a horizontal type in which the axial direction of the cylinder 310 is horizontal, but may be a vertical type in which the axial direction of the cylinder 310 is vertical. The mold clamping device combined with the vertical injection device 300 may be either vertical or horizontal. Similarly, the mold clamping device combined with the horizontal injection device 300 may be either horizontal or vertical.

(Mobile device)

In the description of the moving device 400, the moving direction of the screw 330 (for example, the X-axis negative direction) during filling is set to the front, and the moving direction of the screw 330 (for example, the X-axis positive direction) during metering is set to the rear, as in the description of the injection device 300.

The movement device 400 advances and retracts the injection device 300 relative to the mold device 800. The moving device 400 presses the nozzle 320 against the die device 800 to generate a nozzle contact pressure. The traveling apparatus 400 includes a hydraulic pump 410, a motor 420 as a driving source, a hydraulic cylinder 430 as a hydraulic actuator, and the like.

The hydraulic pump 410 has a 1 st port 411 and a 2 nd port 412. The hydraulic pump 410 is a pump capable of rotating in both directions, and generates hydraulic pressure by switching the rotation direction of the motor 420 so that a working fluid (for example, oil) is sucked from one of the 1 st port 411 and the 2 nd port 412 and discharged from the other port. The hydraulic pump 410 may suck the working fluid from the tank and discharge the working fluid from any one of the 1 st port 411 and the 2 nd port 412.

The motor 420 operates the hydraulic pump 410. The motor 420 drives the hydraulic pump 410 by a rotation direction and a torque corresponding to a control signal from the control device 700. The motor 420 may be an electric motor or an electric servo motor.

Hydraulic cylinder 430 has a cylinder body 431, a piston 432, and a piston rod 433. Cylinder body 431 is fixed relative to injection device 300. Piston 432 divides the interior of cylinder body 431 into a front chamber 435 that is a1 st chamber and a rear chamber 436 that is a2 nd chamber. The piston rod 433 is fixed with respect to the fixed platen 110.

The front chamber 435 of the hydraulic cylinder 430 is connected to the 1 st port 411 of the hydraulic pump 410 via the 1 st flow path 401. The working fluid discharged from the 1 st port 411 is supplied to the front chamber 435 via the 1 st flow path 401, and the injection device 300 is pushed forward. The injection device 300 is advanced and the nozzle 320 is pressed against the stationary mold 810. The front chamber 435 functions as a pressure chamber that generates a nozzle contact pressure of the nozzle 320 by the pressure of the working fluid supplied from the hydraulic pump 410.

On the other hand, the rear chamber 436 of the hydraulic cylinder 430 is connected to the 2 nd port 412 of the hydraulic pump 410 via the 2 nd flow path 402. The working fluid discharged from the 2 nd port 412 is supplied to the rear chamber 436 of the hydraulic cylinder 430 via the 2 nd flow path 402, whereby the injection device 300 is pushed rearward. The injection device 300 is retracted and the nozzle 320 is separated from the stationary mold 810.

In the present 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 rotational motion of the electric motor into linear motion of the injection device 300 may be used.

(Control device)

As shown in fig. 1 to 2, the control device 700 is configured by a computer, for example, and includes a CPU (Central Processing Unit: central processing unit) 701, a storage medium 702 such as a memory, an input interface 703, an output interface 704, and a communication interface 705. The control device 700 performs various controls by causing the CPU701 to execute a program stored in the storage medium 702. The control device 700 receives a signal from the outside through the input interface 703 and transmits a signal to the outside through the output interface 704.

The control device 700 repeatedly performs a metering process, a mold closing process, a pressure increasing process, a mold closing process, a filling process, a pressure maintaining process, a cooling process, a pressure releasing process, a mold opening process, an ejection process, and the like, to thereby repeatedly produce a molded product. A series of operations for obtaining a molded product, for example, an operation from the start of a metering process to the start of the next metering process is also referred to as "injection" or "molding cycle". The time required for one shot is also referred to as "molding cycle time" or "cycle time".

The one-shot molding cycle includes, for example, a metering step, a mold closing step, a pressure increasing step, a mold closing step, a filling step, a pressure maintaining step, a cooling step, a pressure releasing step, a mold opening step, and an ejection step in this order. The sequence here is the sequence in which the respective steps are started. The filling step, the pressure maintaining step, and the cooling step are performed during the mold clamping step. The start of the mold clamping process may be coincident with the start of the filling process. The end of the decompression step corresponds to the start of the mold opening step.

In addition, a plurality of steps may be performed simultaneously for the purpose of shortening the molding cycle time. For example, the metering step may be performed in the cooling step of the previous molding cycle, or may be performed during the mold clamping step. In this case, the mold closing step may be performed at the beginning of the molding cycle. The filling process may be started in the mold closing process. The ejection step may be started in the mold opening step. When an opening/closing valve for opening/closing the flow path of the nozzle 320 is provided, the mold opening process may be started in the metering process. Even if the mold opening process is started in the metering process, the molding material does not leak from the nozzle 320 as long as the opening/closing valve closes the flow path of the nozzle 320.

The one-shot molding cycle may include steps other than the metering step, the mold closing step, the pressure increasing step, the mold closing step, the filling step, the pressure maintaining step, the cooling step, the pressure releasing step, the mold opening step, and the ejection step.

For example, the pre-metering suck-back step of retracting the screw 330 to a preset metering start position may be performed after the end of the pressure maintaining step and before the start of the metering step. The pressure of the molding material stored in front of the screw 330 can be reduced before the start of the metering process, and the screw 330 can be prevented from rapidly backing up when the metering process is started.

After the completion of the metering step and before the start of the filling step, the post-metering suck-back step of retracting the screw 330 to a preset filling start position (also referred to as "injection start position") may be performed. The pressure of the molding material stored in front of the screw 330 can be reduced before the start of the filling process, and leakage of the molding material from the nozzle 320 can be prevented before the start of the filling process.

The control device 700 is connected to an operation device 750 that receives an input operation from a user and a display device 760 that displays a screen. The operation device 750 and the display device 760 are constituted by, for example, a touch panel 770, and may be integrated. The touch panel 770 as the display device 760 displays a screen under the control of the control device 700. Information such as the setting of the injection molding machine 10, the current state of the injection molding machine 10, and the like may be displayed on the screen of the touch panel 770. The touch panel 770 can receive an operation in a displayed screen area. Further, an operation unit such as a button or an input field for receiving an input operation by a user may be displayed in the screen region of the touch panel 770. The touch panel 770 as the operation device 750 detects an input operation of a user on a screen, and outputs a signal corresponding to the input operation to the control device 700. Thus, for example, the user can perform setting (including input of a set value) of the injection molding machine 10 by operating the operation unit provided on the screen while checking information displayed on the screen. The user can operate the operation unit provided on the screen, and thereby operate the injection molding machine 10 corresponding to the operation unit. The operation of the injection molding machine 10 may be, for example, the operations (including stopping) of the mold clamping device 100, the ejector 200, the injection device 300, the moving device 400, and the like. The operation of the injection molding machine 10 may be a switching of a screen displayed on the touch panel 770 as the display device 760.

The operation device 750 and the display device 760 according to the present embodiment are integrated into the touch panel 770, but may be provided independently. Further, a plurality of operation devices 750 may be provided. The operation device 750 and the display device 760 are disposed on the operation side (Y-axis negative direction) of the mold clamping device 100 (more specifically, the stationary platen 110).

(Embodiment 1)

Fig. 3 is a diagram showing constituent elements of a control device 700 of the injection molding machine 10 according to one embodiment, with functional blocks. The functional blocks illustrated in fig. 3 are conceptual functional blocks, and are not necessarily physically configured as illustrated. All or part of the functional blocks may be functionally or physically distributed/integrated in arbitrary units. All or any part of the processing functions performed in the respective functional blocks are realized by programs executed by the CPU 701. Or the functional blocks may be implemented as hardware based wired logic. As shown in fig. 3, the CPU701 of the control device 700 includes a setting unit 711, an acquisition unit 712, a determination unit 713, a log control unit 714, and a display control unit 715. The control device 700 further includes a log storage unit 721 in the storage medium 702.

The log storage unit 721 stores log information related to the injection molding machine 10. The log information is, for example, information related to the setting and actual injection molding each time the injection molding is performed in the injection molding machine 10. The specific log information will be described later.

Next, a method used by the control device 700 according to the present embodiment for monitoring the gas burn will be described.

Fig. 4 is a diagram showing the molding material M flowing into the mold device 800 according to the present embodiment and the sensor 841 provided in the mold device 800.

The molding material M shown in fig. 4 is, for example, a resin. The molding material M flows into the cavity space 801 inside the mold device 800. The cavity space 801 is formed at the parting surface 830 of the fixed mold 810 and the movable mold 820. Parting plane 830 is commonly referred to as a parting line.

When the molding material M flows into the cavity space 801, the gas in the cavity space 801 escapes to the outside of the mold apparatus 800 as indicated by an arrow via the parting surface 830 or the like, thereby filling the entire cavity space 801 with the molding material M.

A sensor (an example of a detection unit) 841 is provided in a cavity space 801 in the mold device 800 of the injection molding machine 10 near the end of a flow path indicated by the cavity space 801. That is, the end of the flow path indicates the end where the molding material filled in the cavity space 801 reaches. In the present embodiment, the sensor 841 may be disposed near the end of the flow path, and may not be disposed in the final filling portion. That is, the sensor 841 may be capable of detecting the state of the end of the flow path of the die apparatus 800.

The sensor 841 detects at least the pressure inside the mold device 800. The sensor 841 detects at least one or more of the temperature inside the mold device 800 and the distance from the front end (flow front) of the flowing molding material M. Thus, the sensor 841 is provided with a pressure sensor, for example. The sensor 841 may be only a pressure sensor, and may also include at least one of a temperature sensor, a distance sensor (e.g., a laser sensor). Further, based on the detection result of the sensor 841, at least one or more of the condition of the gas in the cavity space 801 and the condition of the molding material M flowing in the cavity space 801 can be estimated.

The pressure sensor serving as the sensor 841 detects the pressure of the gas or the molding material M adjacent to the sensor 841.

A temperature sensor as the sensor 841 detects the temperature of the gas or the molding material M adjacent to the sensor 841.

The distance sensor as the sensor 841 detects a distance from the flow front end of the molding material M with reference to the position of the sensor 841.

Fig. 5 is a diagram showing a change in the flow of the molding material M in the mold device 800 according to the present embodiment. In the state shown in fig. 5 (a), the molding material M flows along an arrow 1511 by the filling step. When the position of the screw 330 reaches the set position, V/P is switched from the filling step to the pressure maintaining step.

In the situation shown in fig. 5 (B), after V/P switching is performed, screw 330 is retracted at a slight speed as indicated by arrow 1521. The molding material M flows in the direction indicated by the arrow 1522 by pressure alleviation.

In the case shown in fig. 5 (C) which follows, in the pressure maintaining step, the injection motor 350 is driven to push the screw 330 forward, the pressure of the molding material at the tip portion of the screw 330 (hereinafter, also referred to as "holding pressure") is maintained at the set pressure, and the molding material remaining in the cylinder 310 is pushed toward the mold device 800. Thereby, the molding material M moves in the direction indicated by the arrow 1523.

In the case shown in fig. 5D, the molding material M is moved in the direction indicated by an arrow 1524 in the pressure maintaining step, and the gas is discharged, so that the molding material M is filled up to the end of the flow path (so-called filled state).

The control of the movement of the molding material shown in fig. 5 is an example, and is not limited to the above control. For example, the time at which the filling process is switched to the pressure maintaining process is an example, and the pressure maintaining process may be switched to, for example, the time at which the filling process is switched to the filling state or after the filling state is switched to the filling state. In addition, the pressure may be maintained in the filling step.

Fig. 6 is a graph showing changes in temperature and pressure from the start of filling to the holding pressure. In the example shown in fig. 6, the changes in temperature 1601 and pressure 1602 detected by sensor 841 are shown. In the example shown in fig. 6, the speed of the screw 330 is controlled as a filling step. Then, at time T ₁₁, a so-called V/P switching is performed from the filling process to the holding pressure process. In the pressure maintaining step, the molding material remaining in the cylinder 310 is pushed toward the mold device 800 while the holding pressure of the molding material at the tip end portion of the screw 330 is maintained at the set pressure.

The pressure 1602 of the gas in the cavity space 801 that has risen by the filling step gradually decreases after a lapse of a small time after switching to the holding step.

At time T ₁₂, the molding material M is filled up to the end of the flow path (so-called filled state). That is, the molding material M contacts the sensor 841, and thus the temperature 1601 rises. In other words, the time (inflection point) at which the sensor 841 detects the rapid temperature rise becomes the time (filling time) at which the molding material M fills up to the end of the flow path.

In the present embodiment, when the difference between the last detected temperature and the last detected temperature exceeds 10 degrees, the determination unit 713 determines that the molding material M is filled up to the end of the flow path (at the time of filling up). The method for determining whether or not the temperature difference exceeds 10 degrees according to the present embodiment is an example of a method for determining when the vehicle is full, and is not limited to this method, and other methods may be used. The "10 degrees" of the determination condition may be set to an appropriate value according to the embodiment. As a method of determining the filling time, for example, a case may be mentioned in which the distance sensor of the sensor 841 determines that the distance from the flow front end of the molding material M is "0".

Then, after the time T ₁₂ reaches the full state, the sensor 841 detects the pressure of the molding material (resin pressure). In this way, when the mold is in the filled state at time T ₁₂, the detected pressure is switched from the gas pressure to the pressure of the molding material (resin pressure). Thereby, the detected pressure also rises.

If the injection molding is repeated, the components of the molding material M are deposited on the parting surface 830 to form mold scales. When the volume amount of the mold deposit increases, it is difficult to discharge the gas in the cavity space 801 to the outside of the cavity space 801 during the filling of the molding material M. As a result, the gas remaining in the cavity space 801 is compressed adiabatically and becomes high temperature, and the molded product burns and becomes a defective product.

That is, when gas combustion occurs, the temperature rises sharply due to adiabatic expansion of the gas present at the end of the flow path of the die apparatus 800 immediately before filling. The pressure in the cavity space 801 rises together with the temperature.

Conventionally, in a post-molding inspection process, a worker refers to a molded article to determine whether or not gas burn has occurred. When it is determined that gas burning has occurred, it is determined that gas is difficult to escape due to accumulation of mold scales, production of the molded article is stopped, and the mold device is cleaned. When this method is used, it is not possible to identify whether or not gas burn has occurred before inspecting the molded article, and therefore, a plurality of gas burned defective products are produced.

Therefore, the control device 700 according to the present embodiment determines whether or not gas burn occurs in the molded product based on the pressure detected by the sensor 841 at a time when the molded product is in the filled state. The determination of occurrence of gas burn according to the present embodiment is not limited to the actual occurrence of gas burn, and may include a state in which the possibility of occurrence of gas burn is high. That is, in the present embodiment, when the same pressure as that in the case where the gas burn is generated is detected based on the correspondence between the pressure detected in the past and the gas burn, the determination is made as to whether the gas burn is actually generated or not.

Fig. 7 is a diagram illustrating a change in pressure detected by the sensor 841 when the mold device 800 according to the present embodiment is in the filled state. The horizontal axis represents the number of shots (an example of the number of shots) from the time point when the mold device 800 is cleaned, and the vertical axis represents the pressure detected when the mold device is in the filled state (in other words, when the mold device is determined to be in the filled state based on the detected temperature). The lines 1701 to 1705 differ only in cleaning state and the like and in injection condition and the like.

Lines 1701 to 1705 shown in fig. 7 can confirm that the pressure at the time point when the filled state is brought into the filled state gradually increases every time the molded article is produced from the time point when cleaning is performed, in other words, every time the number of shots increases.

In the example shown in fig. 7, when the threshold value Pth1 is exceeded, the pressure increases sharply for each line 1701 to 1705. This is because the gas is difficult to be discharged to the outside of the cavity space 801 due to the increase in the volume amount of the mold scale, and a large amount of gas is accumulated in the cavity space 801, so that the pressure rapidly rises when the temperature is increased due to adiabatic compression. That is, it can be estimated that gas burn occurs in the molded article at the time when the detected pressure exceeds the threshold value Pth 1.

The number of shots until the threshold value Pth1 is reached varies depending on the cleaning state of the mold device 800, the environment in which injection molding is performed, and the like, for each of the lines 1701 to 1704. However, the points at which the gas burn occurs in the molded article at the time when the pressure detected by the sensor 841 exceeds the threshold value Pth1 are the same as each other. In addition, line 1705 is a case where the pressure at the time of reaching the full state does not reach the threshold Pth1 within the range shown in fig. 7, and no gas burn occurs in the molded article. That is, when the threshold Pth1 is not reached even though the number of shots is large, it is indicated that no gas burn occurs in the molded article.

Therefore, in the control device 700 according to the present embodiment, whether or not gas burn occurs is determined based on whether or not the pressure at the time of becoming the full state (in other words, the full state is determined based on the detected temperature) exceeds the threshold value Pth 1. In the present embodiment, the time for determining whether or not gas burn has occurred is not limited to the time when the state is full. However, since the time when the gas burn occurs substantially coincides with the time when the gas burn occurs during filling, the accuracy of determining whether or not the gas burn occurs can be improved by using the pressure during filling for determination.

Referring back to fig. 3, the respective configurations of the control device 700 will be described.

The setting unit 711 sets a threshold Pth1, which is a reference for determining whether or not burn-up has occurred. The threshold value Pth1 is set, for example, to a pressure detected by the sensor 841 when the gas burn occurs by actually repeating the production of the molded article in the injection molding machine 10. The set threshold value Pth1 may be a value input by the user from the operation device 750, or may be set automatically by the control device 700.

The acquisition unit 712 acquires signals (an example of information) indicating the detection results from various sensors provided in the injection molding machine 10. For example, the acquisition unit 712 acquires a signal indicating a detection result based on the pressure and temperature from the sensor 841. Thus, the acquisition unit 712 can acquire signals indicating the pressure and the temperature from the sensor 841 provided in the cavity space 801 in the mold device 800 of the injection molding machine 10 near the end where the molding material filled in the cavity space 801 reaches.

The determining unit 713 determines whether the molding material is filled up to the flow end of the mold device 800 based on the temperature from the sensor 841 acquired by the acquiring unit 712. In the present embodiment, the method of detecting the pressure is not limited to the method of detecting the pressure at the time when the molding material is filled up to the flow end of the mold device 800. That is, the pressure increase such as the gas burn occurs not only at the time of filling the molding material but also before and after the time. That is, the timing of detecting the pressure is preferably set within ±0.05 seconds, for example, from the time when the molding material fills up to the flow end of the mold device 800.

Further, the determination as to whether the molding material is filled up to the flow end of the mold device 800 is not limited to the method using the temperature, and whether the molding material is filled up may be determined based on the distance from the molding material detected by the sensor 841. For example, it may be determined that the molding material is filled at the time when the distance from the sensor 841 to the molding material is "0".

Then, the determining unit 713 determines whether or not the pressure detected by the sensor 841 exceeds the threshold value Pth1 set by the setting unit 711 at a time point near the time when the molding material fills up to the flow end (the filled state) of the mold device 800. When the pressure detected by the sensor 841 exceeds the threshold Pth1 set by the setting unit 711, it is determined that the air burn is generated.

In the present embodiment, the time for determining whether or not the gas burn has occurred is not limited to the time when the molding material is filled to the end of the flow (in the filled state). That is, since the gas burn occurs when it is difficult to exhaust the gas from the mold device 800, it can be determined whether the gas burn occurs if it is possible to detect that it is difficult to exhaust the gas from the mold device 800. For example, the determination unit 713 may determine that gas burn has occurred when the pressure detected by the sensor 841 exceeds the threshold Pth2 when the switching is near V/P. The determination of occurrence of gas burn according to the present embodiment is not limited to the actual occurrence of gas burn, and may include a state in which the possibility of occurrence of gas burn is high.

Fig. 8 is a diagram illustrating a change in pressure detected by the sensor 841 at the time of V/P switching in the die apparatus 800 according to the present embodiment. The horizontal axis represents the number of shots from the time point when the mold device 800 is cleaned, and the vertical axis represents the pressure detected at the time of V/P switching.

Lines 1801 and 1802 shown in fig. 8 can confirm that the pressure at the time of V/P switching gradually increases every time a molded article is produced from the time point at which cleaning is performed, in other words, every time the number of shots increases. Lines 1801, 1802 illustrate cases where molding conditions (e.g., design of screw 330, etc.) are different.

The determination unit 713 may determine whether the pressure detected by the sensor 841 at the time of V/P switching exceeds the threshold Pth2. When the pressure detected by the sensor 841 at the time of V/P switching exceeds the threshold Pth2, it is determined that gas burn occurs. The method of detecting the pressure at the time of V/P switching is not limited to this method. The timing of detecting the pressure is preferably set within ±0.05 seconds, for example, from the time of V/P switching.

The log control unit 714 performs control for storing log information of the injection molding machine 10 in the log storage unit 721. For example, when the determination unit 713 determines that the vehicle is full, the log control unit 714 may include the pressure detected by the sensor 841 in the log information and store the pressure in the log storage unit 721.

For example, the log control unit 714 stores actual values, setting information, calculated statistical values, and the like during molding as log information in the log storage unit 721. The setting for saving as log information is performed on the log information screen displayed by the display control unit 715.

When determining whether or not there is a burn using the pressure detected by the sensor 841 at the time of V/P switching, the log control unit 714 may include the pressure detected by the sensor 841 in the log information and store the pressure in the log storage unit 721 when determining V/P switching.

The display control unit 715 performs control to display data such as a display screen on the display device 760.

The display control unit 715 according to the present embodiment may output setting information set by a user in each step of the molding process performed by the injection molding machine 10 or a display screen including an actual value detected in the step to the display device 760. In the present embodiment, an example in which a display screen or the like is output to the display device 760 is described, but the destination of data output is not limited to the display device 760. For example, the display control unit 715 may output data such as a display screen to a communication terminal connected via a network.

The display control unit 715 according to the present embodiment displays, for example, a log information screen that displays actual values, setting information, statistical values, and the like during molding as log information.

Fig. 9 is a diagram illustrating a log information screen outputted by the display control unit 715 according to the present embodiment.

The log information screen 1400 shown in fig. 9 shows a total number 1401, a number of acceptable products 1402, a number of unacceptable products 1403, a number of defective products 1404, a record button 1405, a monitor setting button 1406, a save button 1407, an update button 1408, a statistics list 1420, and an actual list 1430.

Statistics list 1420 shows statistics (e.g., average, range, maximum, minimum, standard deviation) for each of settings fields 1421-1428. The contents displayed in the setting fields 1421 to 1428 can be set by the user. In this embodiment, the items displayed in the setting fields 1421 to 1428 can be displayed, monitored, and log information stored. The monitoring of the present embodiment indicates whether or not the product is a good product based on a predetermined criterion.

The "monitor", "upper limit", and "lower limit" of the statistics list 1420 are information for determining whether or not the molded product in the setting column is defective.

It is shown that when the monitoring of the statistics list 1420 is "cut", the control device 700 does not monitor, and when it is "in", the control device 700 monitors. When "in", the control device 700 determines whether or not the measured actual value in the item shown in the setting column satisfies the criterion shown in "upper limit" and "lower line". The monitoring is switched by the monitoring setting button 1406.

The "reject" of the statistics list 1420 shows the number of molded articles that are not included in the ranges shown in the "upper limit" and the "lower limit".

The setting fields 1421 to 1428 set settings or actual values related to injection molding. The setting fields 1421 to 1428 can be changed to items that the user wishes to monitor. The modification method will not be described.

The actual list 1430 displays, for each shot, a list of setting information set in the items in the setting fields 1421 to 1428 or actual values measured by various sensors. Items set in the setting fields 1421 through 1428 are set to "CH-1" through "CH-8". Then, each shot is associated with a shot number, a shot time, and a shot state as information indicating the shot.

The record button 1405 is a button for receiving whether or not at least one of the set values and the actual values shown in the actual list 1430 is stored as log information. When the record button 1405 is pressed (the "record" is displayed), the log control unit 714 stores information and the like shown in the actual list 1430 as log information in the log storage unit 721.

The monitor setting button 1406 is a button for receiving whether or not to monitor according to the monitored item of the statistics list 1420. When the monitor setting button 1406 (the "monitor in" is displayed) is pressed, whether or not the shot is a defective product is monitored for each shot, and the monitoring result is included in the log information. The monitoring of the statistics list 1420 is switched to "cut" or "enter" depending on whether the monitoring setting button 1406 is pressed.

When the "in" is set by the monitor setting button 1406, the monitoring is performed in accordance with the setting of the "monitor" in the statistics list 1420.

For example, the "pressure at filling" in the setting field 1428 is an item in which the actual value of the pressure detected by the sensor 841 at filling is set. In the present embodiment, the "in" field 1629 is set for the "pressure at filling". As the threshold Pth1, for example, "20.00" (MPa) is set in the upper limit column 1629A. Thus, when the determination unit 713 determines that the pressure at the time of filling is higher than "20.00" (an example of the threshold Pth 1), the number of rejects 1403 increases.

In the present embodiment, an example of the threshold value Pth1 is shown, but the present invention is not limited to "20.00". The threshold value Pth1 differs depending on, for example, the shape of the mold device 800, the type of molding material, and the like.

The save button 1407 is a button for receiving whether or not to save the statistical values (for example, average, range, maximum, minimum, integrated value, standard deviation, etc.) of each of the setting fields 1421 to 1428. When the save button 1407 is pressed, the log control unit 714 saves the statistics for each of the setting fields 1421 to 1428 as log information in the log saving unit 721.

The update button 1408 is a button for receiving whether to update the statistics list 1420 and the actual list 1430 each time the injection molding of the injection molding machine 10 is completed. When the update button 1408 (always is shown) is pressed, the statistics list 1420 and the actual list 1430 are updated each time the injection molding of the injection molding machine 10 is finished.

The total 1401 represents the number of molded articles molded in the injection molding machine 10. The number of acceptable products 1402 indicates the number of molded products determined to be acceptable based on the "monitor", "upper limit", and "lower limit". The number of defective products 1403 indicates the number of molded products determined to be defective based on "monitoring", "upper limit", and "lower limit". The number of rejects 1404 represents the number of molded articles set as rejects.

The display control unit 715 according to the present embodiment displays "20.00" (MPa) in the upper limit column 1629A on the log information screen of the display device 760, and displays a transition in the pressure detected when the display is full in the actual list 1430. Thus, the user can recognize whether or not the molded article produced by the injection molding machine 10 has gas burn.

In the present embodiment, the screen displayed by the display control unit 715 is not limited to the log information screen. For example, the display control unit 715 may display a graph showing a transition of the pressure at the time of filling with respect to the number of shots as shown in fig. 7. The threshold value Pth1 may also be displayed as a line in the graph.

As another example, the display control unit 715 may display a graph showing a transition of the pressure at the time of V/P switching with respect to the number of shots, as shown in fig. 8. The threshold value Pth2 may also be displayed as a line in the graph.

In addition, as a modification, the determination unit 713 may display only the graph shown in fig. 7 or 8 by the display control unit 715 without performing the determination. The user can determine the number of shots until the occurrence of the gas burn and whether or not the gas burn occurs by referring to the graph shown in fig. 7 or 8.

In the present embodiment, when the determination unit 713 determines that the pressure detected by the sensor 841 exceeds the threshold Pth1 at the time of the full state, the display control unit 715 displays a screen indicating that "gas burn in molded product is generated" on the log information screen 1400. The displayed screen is, for example, a pop-up screen.

Thus, the user can recognize that the gas burn is generated. The information output when the pressure detected by the sensor 841 exceeds the threshold value Pth1 is not limited to the display screen at the time of the full state. For example, the control device 700 may output the interest of the generation of the gas burn by using sound, or may notify the communication terminal connected via the network of the interest of the generation of the gas burn.

Next, a processing procedure before gas burn detection in the injection molding machine 10 according to the present embodiment will be described. Fig. 10 is a flowchart showing a processing procedure before gas burn is detected in the injection molding machine 10 according to the present embodiment.

First, the injection molding machine 10 repeats the production of the molded article until the gas burn occurs (step S2001). When gas burn occurs, the control device 700 recognizes the pressure detected by the sensor 841 when filled.

Then, the setting unit 711 of the control device 700 sets the pressure detected when the gas burn occurs as the threshold Pth1 (step S2002).

Then, the injection molding machine 10 starts the production of the molded product under the control of the control device 700 (step S2003).

Then, the acquisition unit 712 acquires the pressure detected by the sensor 841 at the time of filling (step S2004). As described above, the determination unit 713 determines the time of filling based on the temperature detected by the sensor 841.

Then, the determination unit 713 determines whether or not the acquired pressure exceeds the set threshold Pth1 (step S2005). When it is determined that the process is not exceeded (step S2005: no), the injection molding machine 10 performs the production of the next molded article, and the process of step S2004 is performed again.

On the other hand, when it is determined by the determination portion 713 that the acquired pressure exceeds the threshold Pth1 (step S2005: "yes"), the display control portion 715 displays a pop-up screen showing the interest in generating smoldering, and the control device 700 outputs a notification sound. (step S2006).

In the present embodiment, the control can identify that the gas burn is generated by the user.

(Modification of embodiment 1)

In the present embodiment, an example will be described in which whether or not gas burn occurs is determined by the pressure detected when the vehicle is near filling or when the vehicle is near V/P switching. However, the present embodiment does not limit whether or not the gas burn is generated to the determination based on whether or not the pressure of the threshold value or more is detected. Therefore, in the modification, it is determined whether or not the gas burn is generated based on the detected pressure difference.

As shown in fig. 7, when gas burn occurs, the pressure at the time of filling rises sharply. That is, when the detected pressure is higher than the pressure detected at the time of filling up so far, it can be presumed that the occurrence of the gas burn is caused.

Therefore, the determination unit 713 according to the present modification determines whether or not the difference between the pressure detected at the time of the previous filling and the pressure detected at the time of the previous filling is larger than a predetermined value. The predetermined value is, for example, a value of 1 to 1.5MPa. The predetermined value is set according to the embodiment, and is not limited to 1 to 1.5MPa.

In addition, this modification describes an example in which the determination is made based on the pressure difference between 2 consecutive times of the pressures detected at the time of filling. However, in the present modification, the determination based on the pressure difference between 2 consecutive times is not limited, and may be 3 times or more. Further, the determination based on the pressure difference is not limited to the determination using the moving average. For example, whether or not gas burn occurs may be determined based on a moving average of the pressure of 3 times. That is, the determination unit 713 may determine whether or not the air burn has occurred based on the difference between the moving average calculated at this time and the moving average calculated last time.

Further, in the present modification, for example, whether or not the gas burn occurs may be determined based on a pressure difference (in other words, a plurality of discontinuous pressure differences) detected at a time interval when the vehicle is near the filling time or when the vehicle is near the V/P switching time, instead of determining whether or not the gas burn occurs based on a plurality of continuous pressure differences detected at a time when the vehicle is near the filling time or when the vehicle is near the V/P switching time.

That is, when the pressure difference detected between the 1 st injection molding and the 2 nd injection molding performed after the 1 st injection molding at the time of the near-filling or the near-V/P switching satisfies the predetermined condition, the determination unit 713 may determine that there is gas burn in the molded article produced by the 2 nd injection molding.

In the above embodiment, an example in which whether or not the occurrence of the gas burn is determined based on whether or not the pressure exceeds the threshold value has been described, and in a modification, an example in which whether or not the occurrence of the gas burn is determined based on whether or not the pressure difference is larger than a predetermined value has been described. However, in the above embodiments and modifications, the method of determining whether or not there is occurrence of gas burn is not limited to the above method. That is, the pressure detected by the sensor 841 may be determined whether or not gas burn occurs in the molded product according to a preset condition. That is, it is preferable to set the molding material in the cavity space 801 in a judgment based on a predetermined condition related to the pressure of the flowing end of the molding material.

In the above embodiments and modifications, since the worker can immediately detect the gas burn without checking the molded product, it is possible to suppress the state in which the production of the molded product is continued in a state in which the gas burn is generated.

(Embodiment 2)

In the above embodiment, an example of determining whether or not gas burn occurs has been described. However, the present invention is not limited to the above embodiment and modification, and whether or not the gas burn occurs is determined based on the pressure detected when the vehicle is near the filling or when the vehicle is near the V/P switching. That is, the period until the occurrence of the gas burn may be predicted from the change in the pressure detected when the vehicle is near the filling or when the vehicle is near the V/P switching.

The period until the occurrence of the gas burn indicates how long it is until the occurrence of the gas burn, and is one or more of the number of times (for example, the number of shots, the number of molding times, the number of production times (the number of production), etc.) and the time (for example, the operation time, the molding time, the production time, etc.). The period until the occurrence of the gas burn is not limited to the number of times or the time represented by a numerical value or a character string, and may be represented by a graph or the like. An example of predicting the number of shots and time (for example, the operation time) will be described below as an example of prediction of the period.

Conventionally, in an injection molding machine, the production of a molded article is repeated in accordance with a predetermined cycle. The predetermined cycle is, for example, gas firing of the molded article or cleaning of the mold device. By repeating this cycle, the number of shots until the molded product is burned can be grasped. For example, it is assumed that gas burn occurs at 10000 shots in the 1 st production, at 6000 shots in the 2 nd production, and at 13000 shots in the 3 rd production.

That is, the number of shots until the occurrence of gas firing varies depending on a plurality of factors such as the batch of molding material (fine component difference), the moisture content included in the molding material, the state of the contact surface between the stationary mold and the movable mold, the surface state of the pipe-shaped device, the degree of cleaning of the mold device, the degree of occurrence of gas from the molding material (variation in plasticization), the temperature of the mold device, the size of the mold device, and the mold clamping force.

Therefore, in the above-described conventional method, it is conceivable to stop the production after the 4 th and subsequent shots by a predetermined number so as not to generate gas burn. In this case, the number of shots is, for example, 5000 shots so as not to cause gas burn. That is, by cleaning the mold device after 5000 shots are completed, the occurrence of gas burn can be suppressed. However, when the mold device is cleaned after 5000 shots, production needs to be stopped. At this time, although there is a possibility that the production can be continued without generating gas burn even after the execution of the injection for 13000 times, the production is stopped after 5000 times of the injection, and thus the burden of cleaning the mold device becomes large and there is a possibility that the production efficiency is lowered.

Therefore, the log control unit 714 according to the present embodiment predicts the occurrence of the gas burn based on the change in the pressure detected by the sensor 841 when the V/P is switched or when the filling is performed. That is, the log control unit 714 calculates the number of shots and the time until the condition for generating gas burn is satisfied, based on a change between the pressure detected at the time of the near V/P switching or near filling of the 1 st injection molding and the pressure detected at the time of the near V/P switching or near filling of the 2 nd injection molding performed after the 1 st injection molding. Then, the display control unit 715 displays the calculated number of shots and time (an example of the period).

In the present embodiment, the predicted number of shots and the predicted time period are displayed until the gas burn occurs, but any one or more of the number of shots and the time period may be displayed. In the present embodiment, the description is given of the method of displaying the number of shots and the time until the air burn occurs in the molded product, but the output method is not limited to display, and sound may be output or transmitted to the communication terminal.

That is, as shown in fig. 7 and 8 of embodiment 1, when gas burn occurs, a pressure equal to or higher than the threshold value is generated at the time of V/P switching or the time of filling. Therefore, in the present embodiment, the log control unit 714 estimates the number of shots required until the threshold value is exceeded, based on the degree of change in the pressure detected when the V/P switch is made or when the filling is made.

The log control unit 714 according to the present embodiment calculates an approximate expression indicating the correspondence between the number of shots and the detected pressure, based on the values of the plurality of pressures detected by the sensor 841 at the time of filling. The approximate expression may be calculated using a pressure from the start of cleaning to the present, or using a pressure of a predetermined injection amount (for example, several tens of injections) up to the present. The approximation formula may be a one-time formula, a two-time formula, a three-time formula, or the like.

For example, in the example shown in fig. 7, the rate of increase increases as the detected pressure approaches the threshold value Pth 1. Therefore, when the approximation formula is calculated using the pressure from the start of cleaning to the present, the quadratic formula or the cubic formula is preferable. On the other hand, when the approximation formula is used once, it is preferable to use the pressure of the predetermined injection amount up to now (for example, the pressure of several tens of times of injection amount).

The log control unit 714 is not limited to a method of calculating an approximation formula indicating the pressure detected by the sensor 841 at the time of filling, and may calculate an approximation formula indicating the correspondence between the number of shots and the pressure based on the pressure detected by the sensor 841 at the time of V/P switching.

In the example shown in fig. 8, in the examples shown by lines 1801 and 1802, it can be confirmed that the pressure at the time of V/P switching gradually increases every time the molded article is produced from the time point at which cleaning is performed, in other words, every time the number of shots increases.

Therefore, when a change in pressure represented by line 1801 is detected, log control unit 714 calculates an approximation formula "y=a1·x+b1" represented by line 1811. The variables a1 and b1 are assigned to the number of shots x and the pressure y based on the pressure change indicated by the line 1801.

When detecting a change in pressure represented by line 1802, log control unit 714 calculates an approximation formula "y=a2·x+b2" represented by line 1812. The variables a2 and b2 are assigned to the number of shots x and the pressure y based on the pressure change indicated by the line 1802.

That is, in the example shown in fig. 8, the log control unit 714 calculates the approximation equation, and then substitutes the threshold value Pth2 into y of the approximation equation, whereby the number of shots x predicted to occur as gas burn can be derived. The log control unit 714 can calculate the time until the occurrence of gas burn based on the number x of shots predicted to be gas burn and the time required for each shot. In addition, the calculation method can be applied not only to V/P switching but also to the above-described filling.

In the example shown in fig. 8, the case where the approximation formula is the first-order formula is described, but the same calculation method may be used for the case of the second-order formula or the third-order formula.

The number of shots and the time until the gas burn calculated by the log control unit 714 are displayed by the display control unit 715.

Fig. 11 is a diagram illustrating a burn-up prediction information screen outputted by the display control unit 715 according to the present embodiment.

The gas burn prediction information screen 2100 shown in fig. 11 displays a filling detection 2101, a gas burn time pressure 2102, a predicted charge number 2103 until gas burn, a predicted time 2104 until gas burn, a gas burn prediction alarm 2105, and an alarm notification setting 2106.

The fill detection 2101 sets whether or not to detect fill. The fullness detection 2101 is set, for example, in response to an input from the operation device 750. The "automatic" and "cut" can be switched in the fill detection 2101. When "automatic" is set in the full-fill detection 2101, the determination unit 713 performs the detection at the time of the full-fill described above.

The gas burn time pressure 2102 sets the pressure (threshold value) at which gas burn is detected. The gas-firing pressure 2102 is set, for example, in accordance with an input from the operation device 750. In the present embodiment, when the pressure is set, the determination unit 713 determines whether or not the gas burn has occurred based on the pressure (threshold), and the log control unit 714 calculates the number of shots and the time until the gas burn has occurred based on the set pressure (threshold).

The predicted shot number 2103 until gas burn is generated shows the shot number calculated by the log control unit 714 until gas burn is generated.

The predicted time 2104 until the gas burn is generated shows the time until the gas burn is generated calculated by the log control unit 714.

The gas burn prediction alarm 2105 sets whether or not to output an alarm before gas burn occurs. The gas burn prediction alarm 2105 is set, for example, in response to an input from the operation device 750. The "on" and "off" can be switched in the gas burn prediction alarm 2105. When "in" is set in the gas burn prediction alarm 2105, the control device 700 outputs an alarm indicating that gas burn is imminent before gas burn occurs.

The alarm notification setting 2106 sets a time at which an alarm is notified. The alarm notification setting 2106 is set, for example, in response to an input from the operation device 750. In the present embodiment, the alarm is output at a timing earlier than the number set in the alarm notification setting 2106 for the number of shots predicted to occur due to gas burn.

For example, when the predicted shot number until the gas burn is "1000" and "10" is set in the alarm notification setting 2106, an alarm is output at the time when the shot number is "990". The alarm may be a sound, or may be a pop-up display or a notification to the communication terminal.

The air burn prediction information screen outputted by the display control unit 715 is not limited to the screen shown in fig. 11, and may be other screen types. For example, the display control unit 715 may display a map showing the pressure change until the present by indicating the value of the pressure detected by the sensor 841 as shown in fig. 7 or 8. The threshold value for determining whether or not there is occurrence of burn-in may be displayed in an overlapping manner in the figure. Further, the pressure transition to the threshold value may be predicted from the pressure transition to the present. The prediction of the pressure transition may be calculated by any method, for example, the approximation formula of fig. 8 described above, regardless of the known method. The worker according to the present embodiment can perform work in consideration of the prediction showing the period until the occurrence of gas burn.

In the present embodiment, since the alarm is notified before the occurrence of the gas burn, the worker can start the process of coping with the gas burn from before the occurrence of the gas burn.

Next, a process procedure before an alarm is output in the control device 700 according to the present embodiment will be described. Fig. 12 is a flowchart showing the processing steps before an alarm is output in the control device 700 according to the present embodiment.

The setting unit 711 of the control device 700 sets the pressure at the time of filling, which is detected when the gas burn occurs, as a threshold Pth1 (step S2201).

Then, the injection molding machine 10 starts the production of the molded product under the control of the control device 700 (step S2202).

Then, the acquisition unit 712 acquires the pressure detected by the sensor 841 at the time of filling (step S2203). As in the above embodiment, the determination unit 713 determines the time of filling based on the temperature detected by the sensor 841.

The log control unit 714 predicts (calculates) the number of shots until the threshold is exceeded and the time period based on the pressure at the time of filling acquired so far (step S2204).

The display control unit 715 displays the number of shots, which is the prediction result, and the time on the burn period prediction information screen (step S2205).

Then, the determination unit 713 determines whether or not the number of shots up to the threshold is equal to or less than the number of shots set in the alarm notification setting 2106 based on the current number of shots (step S2206). When it is determined that the number of shots is larger than the set number of shots (step S2206: NO), the process proceeds from step S2203 again.

On the other hand, when the determination unit 713 determines that the number of shots up to the threshold is equal to or less than the number of shots set in the alarm notification setting 2106 based on the current number of shots (yes in step S2206), the control device 700 outputs a notification sound indicating an alarm (step S2207). At this time, the display control unit 715 may display a pop-up screen indicating that the gas burn is approaching.

In the present embodiment, the user can recognize the occurrence of gas burn in advance by the control described above.

In the present embodiment, by performing the control described above, the time until the occurrence of gas burn and the number of shots are predicted, and thus the production can be continued until the gas burn is about to occur. This suppresses the frequency of cleaning of the mold device 800, thereby improving productivity. Further, the cleaning frequency is suppressed, so that the cleaning load can be reduced.

In the present embodiment, since the time until the gas burn and the number of shots can be predicted, the cleaning of the die apparatus 800 can be schedule-managed. This can reduce the standby time for cleaning the mold device 800, and thus can reduce the workload.

In the present embodiment, since the production can be continued until the time when the gas burn is to occur, the cleaning frequency of the mold device 800 can be controlled to the minimum, and the productivity can be improved.

In the present embodiment, the time until the gas firing is predicted, and a plan can be made to clean the mold device 800.

< Action >

In the above embodiment and modification, by providing the above configuration, the control device 700 monitors the molded product for the gas burn based on the detected pressure, thereby reducing the occurrence of defective products.

In the above embodiment and modification, by providing the above configuration, information on the gas burn (for example, whether gas burn occurs or a predicted time until gas burn occurs or the like) can be presented to the user without checking the gas burn of the molded product. Thus, measures related to gas burning can be immediately taken, and thus, the production of a molded article can be suppressed from being continued in a state where gas burning occurs. This reduces the inspection load and suppresses production defects, thereby reducing the production cost.

In the above embodiment, an example in which the display device 760 displays information under the control of the control device 700 as the display device of the injection molding machine has been described. However, the above embodiment shows one embodiment of the display device of the injection molding machine, and is not limited to this embodiment. For example, control for displaying information may be performed by a control device inside the display device 760.

The embodiments of the control device for an injection molding machine and the display device for an injection molding machine according to the present invention have been described above, but the present invention is not limited to the above embodiments and the like. Various changes, modifications, substitutions, additions, deletions and combinations can be made within the scope described in the claims. These are, of course, within the technical scope of the present invention.

Claims

1. A control device for an injection molding machine is provided with:

an acquisition unit configured to acquire information indicating pressure from a detection unit provided in a cavity space in a mold device of an injection molding machine in the vicinity of an end where a molding material filled in the cavity space reaches; and

And a control unit configured to determine whether or not gas burn occurs in a molded article produced by the injection molding machine, and predict or display a period until gas burn occurs in the molded article, based on a predetermined condition related to the pressure detected at a time point near a time point at which the injection molding machine switches from a filling process to a pressure maintaining process or near a time point at which the molding material fills up to the end portion.

2. The control device of an injection molding machine according to claim 1, wherein,

When the pressure detected at the timing exceeds a threshold set as the predetermined condition, the control unit determines that there is air burn in the molded article produced by the injection molding machine.

3. The control device of an injection molding machine according to claim 1, wherein,

The control unit determines that there is a gas burn in the molded article produced by the 1 st injection molding when a difference between the pressure detected at the time of the 1 st injection molding and the pressure detected at the time of the 2 nd injection molding performed after the 1 st injection molding is larger than a value set as the predetermined condition.

4. The control device of an injection molding machine according to claim 1, wherein,

The control unit calculates a time or an injection number required until the predetermined condition is satisfied, based on a change between the pressure detected at the time of the 1 st injection molding and the pressure detected at the time of the 2 nd injection molding performed after the 1 st injection molding, and outputs information on the time or the injection number.

5. A display device of an injection molding machine is provided with:

And a display control unit configured to display a screen showing a transition of the pressure detected at a timing near a switching from a filling process to a holding process of the injection molding machine or near a timing when the molding material is filled up to the end portion and information indicating a reference of the pressure at which gas burn occurs in a molded article produced by the injection molding machine.