MANAGEMENT DEVICE FOR SPRAYING MACHINE, SPRAYING MACHINE AND MANAGEMENT METHOD FOR SPRAYING MACHINE

Abstract

Management device (700) for an injection molding machine (10) comprising a cylinder (310) divided into zones (Z1-Z4) from upstream to downstream along a direction in which a molding material is conveyed, a heater (313) provided in each of the zones (Z1-Z4), and a temperature detector (314) configured to detect an actual temperature in each of the zones (Z1-Z4), wherein the management device (700) is configured, in response to a quantity derived from the actual temperature of a predetermined zone (Z2, Z3) and a temperature set for the predetermined zone (Z2, Z3) exceeding a predetermined value, to reduce the power of the heater (313) provided in the predetermined zone (Z2, Z3), wherein the predetermined zone (Z2, Z3) is one of the zones (Z1-Z4) except for the most upstream zone (Z1) and the most downstream zone (Z4), and in response to the fact that the size continues to exceed the predetermined value after reducing the power of the heater (313) provided in the predetermined zone (Z2, Z3), to determine that abnormal heat generation is occurring in the predetermined zone (Z2, Z3) due to shearing of the mold material, and to increase a temperature set for a zone upstream of the predetermined zone (Z2, Z3) below zones (Z1-Z4).

Description

BACKGROUND 1. Technical field

[0001] The present disclosure relates to management devices for injection molding machines, injection molding machines and management methods for injection molding machines. 2. Description of the state of the art

[0002] Injection molding machines comprise a mold clamping / closing unit configured to open and close a molded part, and an injection unit configured to inject molding material into the molded part (see, for example, JP 2004-306497A). The injection unit includes a cylinder, a temperature control device, and a temperature detector. The cylinder is divided into several zones from upstream to downstream along the direction in which the molding material is fed. The temperature control device is provided in each of the zones. The temperature detector is configured to detect the actual temperature in each of the zones.

[0003] Furthermore, a feedback control of the cylinder temperature based on a predetermined temperature is known (see, for example, JP S63-81 016 A, JP 2012-218 418 A). Reference is also made to the disclosure in JP S61-235 120 A.

[0004] To suppress thermal deterioration of mold materials, shorten the mold cycle time (especially the cooling step time), or for similar reasons, the cylinder temperature can be set low. However, if the cylinder temperature is set too low, abnormal heat generation due to shear occurs, causing mold defects. Abnormal heat generation due to shear is a cause of mold defects that is easily overlooked by an insufficiently trained operator.

[0005] One aspect of the present disclosure is a technique for suppressing design errors. SUMMARY

[0006] The aforementioned objective is achieved through an administrative device and an administrative procedure in accordance with the independent claims.

[0007] A control device according to one aspect of the present disclosure is for an injection molding machine having a cylinder divided into zones from upstream to downstream along a direction in which molding material is conveyed, a temperature control device provided in each of the zones, and a temperature detector configured to detect an actual temperature in each of the zones. The control device is configured to detect abnormal heat generation due to shearing of the molding material based on the actual temperature of a predetermined zone, with the exception of the most upstream and most downstream zones.

[0008] According to one aspect of the present disclosure, it is possible to suppress forming defects. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing the state of an injection molding machine according to one embodiment at the completion of mold opening; Fig. 2 is a view showing the state of the injection molding machine according to the embodiment during mold closing / clamping; Fig. Figure 3 is a diagram showing examples of a cylinder and a spiral; Fig. Figure 4 is a diagram showing an example of a screen in relation to a set temperature of the cylinder; Fig. Figure 5 is a diagram showing an example of a snail; Fig. Figure 6 is a diagram showing a functional block of an example of components of a controller; and Fig. Figure 7 is a diagram showing an example of a screen that provides a notification after detection of abnormal heat generation and before changing the set temperature. DETAILED DESCRIPTION

[0009] Embodiments of the present disclosure are described with reference to the drawings. The drawings refer to the same or corresponding configurations using the same or corresponding symbols, and a description thereof may be omitted. (Injection molding machine)

[0010] Fig. Figure 1 is a diagram showing the state of an injection molding machine according to one embodiment at the completion of mold opening. Fig. Figure 2 is a diagram showing the state of the injection molding machine according to this embodiment during mold closing / clamping. In this description, the X-axis, Y-axis, and Z-axis directions are perpendicular to each other. The X-axis and Y-axis directions represent horizontal directions, and the Z-axis direction represents a vertical direction. If a mold closing / clamping part 100 is of a horizontal type, the X-axis direction is a mold opening / closing direction, and the Y-axis direction is a width direction of an injection molding machine 10. The negative side in the Y-axis direction is referred to as the "operating side," and the positive side in the Y-axis direction is referred to as the "non-operating side."

[0011] As in Fig. 1 and Fig. As shown in Figure 2, the injection molding machine 10 comprises the mold clamping / closing part 100, which opens and closes a mold part 800, an ejector 200, which ejects a molded product in the mold part 800, an injection part 300, which injects a molding material into the mold part 800, a movement part 400, which moves the injection part 300 towards and away from the mold part 800, a control unit 700, which controls the components of the injection molding machine 10, and a frame 900, which supports the components of the injection molding machine 10. The frame 900 comprises a mold clamping / closing part frame 910, which supports the mold clamping / closing part 100, and an injection part frame 920, which supports the injection part 300. Each of the mold clamping / holding frame 910 and the injection frame 920 is installed on a base 2 via at least one height adjuster 930. The control unit 700 is located inside the injection frame 920. Each component of the injection molding machine 10 is described below. (Form-fit / clamping part)

[0012] In the description of the mold closing / clamping part 100, the direction of movement of a movable plate 120 during mold closing (e.g. the positive X-axis direction) is referred to as the "forward direction" and the direction of movement of the movable plate 120 during mold opening (e.g. the negative X-axis direction) is referred to as the "reverse direction".

[0013] The form-closing / clamping part 100 closes, pressurizes, closes / clamps, releases pressure, and opens the form part 800. The form part 800 comprises a stationary form 810 and a movable form 820.

[0014] The mold-closing / clamping part 100, for example, is of a horizontal type, and the mold opening and closing directions are horizontal directions. The mold-closing / clamping part 100 comprises a stationary plate 110 to which the stationary mold 810 is attached, the movable plate 120 to which the movable mold 820 is attached, and a movement mechanism 102 that moves the movable plate 120 in the mold opening and closing direction relative to the stationary plate 110.

[0015] The stationary plate 110 is attached to the frame of the form-closing / clamping frame 910. The stationary form 810 is attached to a surface of the stationary plate 110 that faces the movable plate 120.

[0016] The movable plate 120 is arranged to be movable relative to the mold closing / clamping frame 910 in the mold opening and closing direction. A guide 101, which guides the movable plate 120, is placed on the mold closing / clamping frame 910. The movable mold 820 is attached to a surface of the movable plate 120 that faces the stationary plate 110.

[0017] The movement mechanism 102 moves the movable plate 120 towards and away from the stationary plate 110 in order to close, pressurize, close / clamp, release pressure and open the molded part 800. The movement mechanism 102 comprises a toggle lever carrier 130 spaced apart from the stationary plate 110, a column 140 connecting the stationary plate 110 and the toggle lever carrier 130, a toggle lever mechanism 150 moving the movable plate 120 in the mold opening and closing direction relative to the toggle lever carrier 130, a mold closing / clamping motor 160 actuating the toggle lever mechanism 150, a motion conversion mechanism 170 converting the rotary motion of the mold closing / clamping motor 160 into linear motion, and a mold thickness adjustment mechanism 180 adjusting the distance between the stationary plate 110 and the toggle lever carrier 130.

[0018] The toggle lever carrier 130 is spaced apart from the stationary plate 110 and is arranged on the mold closing / clamping frame 910 to be movable in the mold opening and closing direction. The toggle lever carrier 130 can be movable along a guide placed on the mold closing / clamping frame 910. The guide 101 of the movable plate 120 can also serve as the guide for the toggle lever carrier 130.

[0019] According to this embodiment, the stationary plate 110 is attached to the mold closing / clamping frame 910, and the toggle lever support 130 is arranged to be movable relative to the mold closing / clamping frame 910 in the mold opening and closing direction. However, the toggle lever support 130 can be attached to the mold closing / clamping frame 910, and the stationary plate 110 can be arranged to be movable relative to the mold closing / clamping frame 910 in the mold opening and closing direction.

[0020] The column 140 connects the stationary plate 110 and the toggle lever support 130 with a distance L between them in the mold opening and closing directions. Several columns (e.g., four) can be used as columns 140. The multiple columns 140 are arranged parallel to the mold opening and closing directions and extend according to a mold closing / clamping force. At least one column 140 among the multiple columns 140 can be equipped with a column strain detector 141, which detects the strain of the column 140. The column strain detector 141 transmits a signal indicating the detection result to the controller 700. The detection result of the column strain detector 141 is used to detect the mold closing / clamping force.

[0021] According to this embodiment, the column strain detector 141 is used as a form-closing / clamping force detector to detect a form-closing / clamping force. However, the present disclosure is not limited to this configuration. The form-closing / clamping force detector is not limited to a strain gauge type and can also be a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and its mounting position is not limited to the column 140.

[0022] The toggle mechanism 150 is arranged between the movable plate 120 and the toggle support 130 and moves the movable plate 120 in the mold opening and closing direction relative to the toggle support 130. The toggle mechanism 150 comprises a crosshead 151, which moves in the mold opening and closing direction, and a pair of link groups that are extended and contracted by the movement of the crosshead 151. Each link group comprises a first link 152 and a second link 153, which are extendable and contractable when connected by a pin or the like. The first link 152 is pivotally attached to the movable plate 120 by a pin or the like. The second link 153 is pivotally attached to the toggle support 130 by a pin or the like. The second connecting link 153 is attached to the crosshead 151 via a third connecting link 154.The crosshead 151 is moved towards or away from the toggle lever carrier 130 in order to contract or extend the first connecting link 152 and the second connecting link 153 in order to move the movable plate 120 towards or away from the toggle lever carrier 130.

[0023] The configuration of the toggle lever mechanism 150 is not based on the one in Fig. 1 and Fig. The configuration shown in section 2 is limited. For example, the number of nodes in each link group that is in Fig. 1 and Fig. 2 five amounts, four amounts, and one end of the third connecting link 154 can be connected to the knot of the first connecting link 152 and the second connecting link 153.

[0024] The form-locking / clamping motor 160 is attached to the toggle lever carrier 130 to actuate the toggle lever mechanism 150. The form-locking / clamping motor 160 moves the crosshead 151 towards or away from the toggle lever carrier 130 to contract or extend the first connecting link 152 and the second connecting link 153, thereby moving the movable plate 120 towards or away from the toggle lever carrier 130. The form-locking / clamping motor 160, which is directly connected to the motion conversion mechanism 170, can alternatively be connected to the motion conversion mechanism 170 via a belt or pulley.

[0025] The motion conversion mechanism 170 converts the rotary motion of the form-closing / clamping motor 160 into the linear motion of the crosshead 151. The motion conversion mechanism 170 comprises a spindle shaft and a spindle nut screwed onto the spindle shaft. Balls or rollers may be inserted between the spindle shaft and the spindle nut.

[0026] The mold closing / clamping part 100, under the control of the control unit 700, performs a mold closing process, a pressurization process, a mold closing / clamping process, a pressure relief process, a mold opening process and the like.

[0027] In the mold closing process, the mold closing / clamping motor 160 is driven to move the crosshead 151 at a set speed into a mold closing position, in order to move the moving platen 120 forward, causing the moving mold 820 to contact the stationary mold 810. The position and speed of the crosshead 151 are detected using a mold closing / clamping motor encoder 161 or the like. The mold closing / clamping motor encoder 161 detects the rotation of the mold closing / clamping motor 160 and transmits a signal indicating the detection results to the controller 700.

[0028] A crosshead position detector, which detects the position of the crosshead 151, and a crosshead motion velocity detector, which detects the motion velocity of the crosshead 151, are not limited to the mold closing / clamping motor encoder 161, and general-purpose encoders can be used. Furthermore, a moving plate position detector, which detects the position of the moving plate 120, and a moving plate motion velocity detector 120, which detects the motion velocity of the moving plate, are not limited to the mold closing / clamping motor encoder, and general-purpose encoders can be used.

[0029] During the pressurization process, the mold closing / clamping motor 160 is driven further to move the crosshead 151 from the mold closing end position to a mold closing / clamping position, thereby generating a mold closing / clamping force.

[0030] During the mold closing / clamping process, the mold closing / clamping motor 160 is driven to maintain the position of the crosshead 151 in the mold closing / clamping position. The mold closing / clamping force generated during the pressurization process is maintained during the mold closing / clamping process. During the mold closing / clamping process, a cavity 801 (see Fig. 2) formed between the movable mold 820 and the stationary mold 810, and the injection part 300 fills the cavity 801 with a liquid molding material. The molding material solidifies, resulting in a molded product.

[0031] The number of cavity spaces 801 can be one or more. In the latter case, several molded products are obtained simultaneously. A feed material can be placed in one part of the cavity space 801, and the molding material can fill another part of the cavity space 801. In this way, a molded product is obtained in which the feed material and the molding material are integrated.

[0032] During the pressure relief process, the mold closing / clamping motor 160 is driven to move the crosshead 151 from the mold closing / clamping position to a mold opening start position, thereby moving the movable platen 120 backward to reduce the mold closing / clamping force. The mold opening start position and the mold closing end position can be the same.

[0033] During the mold opening process, the mold closing / clamping motor 160 is driven to move the crosshead 151 at a set speed from the mold opening start position to a mold opening closing position, in order to move the movable plate 120 backwards to separate the movable mold 820 from the stationary mold 810. The ejector 200 then ejects the molded product from the movable mold 820.

[0034] Setting conditions for the mold closing process, the pressurization process, and the mold closing / clamping process are set collectively as a set of setting conditions. For example, the movement speed and positions (including a mold closing start position, a movement speed change position, the mold closing end position, and the mold closing / clamping position) of the crosshead 151 and the mold closing / clamping force for the mold closing process and the pressurization process are set collectively as a set of setting conditions. The mold closing start position, the movement speed change position, the mold closing end position, and the mold closing / clamping position, arranged in that order in the forward direction from the rear, represent the start and end points of sections for which the movement speed is set. The movement speed is set section by section.There can be one or more movement speed switching positions. The movement speed switching position does not need to be set. Only one of the mold closing / clamping position and the mold closing / clamping force can be set.

[0035] Setting conditions for the pressure release and mold opening processes are also configured. For example, the movement speed and positions (the mold opening start position, the movement speed change position, and the mold opening end position) of the crosshead 151 are collectively set as a set of setting conditions for both the pressure release and mold opening processes. The mold opening position, the movement speed change position, and the mold opening end position, arranged in that order in reverse from the front, represent the start and end points of the sections for which the movement speed is set. The movement speed is set section by section. There can be one or more movement speed change positions. The movement speed change position does not have to be set.The mold opening start position and mold closing end position can be the same position. The mold opening end position and the mold closing start position can be the same position.

[0036] Instead of the speed, position, and similar parameters of the crosshead 151, the speed, position, and similar parameters of the moving plate 120 can be set. Furthermore, instead of the crosshead position (e.g., the mold closing / clamping position) or the position of the moving plate, the mold closing / clamping force can also be set.

[0037] The toggle lever mechanism 150 amplifies the drive force of the form-closing / clamping motor 160 and transmits the amplified drive force to the movable plate 120. The amplification factor is also referred to as the "toggle lever amplification factor." The toggle lever amplification factor changes according to the angle θ formed by the first connecting link 152 and the second connecting link 153 (hereinafter also referred to as the "connecting link angle θ"). The connecting link angle θ is determined by the position of the crosshead 151. The toggle lever amplification factor is at its maximum when the connecting link angle θ is 180°.

[0038] If there is a change in the thickness of the molded part 800 due to its replacement or a change in its temperature, the mold thickness is adjusted to achieve a predetermined mold closing / clamping force at the time of mold closing / clamping. For example, when adjusting the mold thickness, the distance L between the stationary plate 110 and the toggle lever support 130 is adjusted so that the link angle θ of the toggle lever mechanism 150 becomes a predetermined angle at the time of mold contact, when the movable mold 820 contacts the stationary mold 810.

[0039] The mold clamping / closing part 100 contains the mold thickness adjustment mechanism 180. The mold thickness adjustment mechanism 180 adjusts the mold thickness by changing the distance L between the stationary plate 110 and the toggle lever support 130. The mold thickness is adjusted, for example, between the end of one molding cycle and the start of the next. The mold thickness adjustment mechanism 180 comprises, for example, a spindle shaft 181 formed at the rear end of each column 140, a spindle nut 182 held on the toggle lever support 130 in such a way that it is rotatable and cannot move forward or backward, and a mold thickness adjustment motor 183 that rotates the spindle nut 182, which engages with the spindle shaft 181.

[0040] The spindle shaft 181 and the spindle nut 182 are provided for each column 140. The rotary drive force of the mold thickness adjustment motor 183 can be transmitted to the multiple spindle nuts 182 via a rotary drive force transmission part 185. It is possible to rotate the multiple spindle nuts 182 synchronously. The multiple spindle nuts 182 can be rotated individually by changing the transmission channel of the rotary drive force transmission part 185.

[0041] The rotary drive power transmission part 185 is constructed as follows, for example. In such a case, a driven gear is formed on the circumference of each spindle nut 182, a drive gear is attached to the output shaft of the mold thickness adjustment motor 183, and an intermediate gear, which engages with the driven gears and the drive gear, is rotatably held in the center of the toggle lever carrier 130. The rotary drive power transmission part 185 can be constructed from a belt and pulleys instead of gears.

[0042] The operation of the mold thickness adjustment mechanism 180 is controlled by the controller 700. The controller 700 drives the mold thickness adjustment motor 183 to rotate the spindle nuts 182. As a result, the position of the toggle lever support 130 relative to the columns 140 is adjusted, and the distance L between the stationary plate 110 and the toggle lever support 130 is adjusted. Several mold thickness adjustment mechanisms can be used in combination.

[0043] The distance L is detected using a mold thickness adjustment motor encoder 184. The mold thickness adjustment motor encoder 184 detects the amount and direction of rotation of the mold thickness adjustment motor 183 and transmits a signal indicating the detection results to the controller 700. The detection results of the mold thickness adjustment motor encoder 184 are used to monitor and control the position of the toggle lever carrier 130 and the distance L. A toggle lever carrier position detector, which detects the position of the toggle lever carrier 130, and a distance detector, which detects the distance L, are not limited to the mold thickness adjustment motor encoder 184, and general-purpose devices can be used.

[0044] The mold clamping / closing part 100 can include a mold temperature adjustment device that adapts the temperature of the mold part 800. The mold part 800 contains a flow path for a temperature adjustment medium. The mold temperature adjustment device adjusts the temperature of the mold part 800 by changing the temperature of the temperature adjustment medium supplied to the flow path of the mold part 800.

[0045] The form-closing / clamping part 100, which according to this embodiment is of a horizontal type, whose form opening and closing directions are horizontal directions, can also be of a vertical type, whose form opening and closing directions are vertical directions.

[0046] The mold clamping / closing element 100, which according to this embodiment includes the mold clamping / closing motor 160 as a drive source, can also include a hydraulic cylinder instead of the mold clamping / closing motor 160. Furthermore, the mold clamping / closing element 100 can include a linear motor for opening and closing the mold and an electromagnet for closing / clamping the mold. (Ejector)

[0047] In the description of the ejector 200, similar to the description of the mold closing / clamping part 100, the direction of movement of the movable plate 120 during mold closing (e.g. the positive X-axis direction) is referred to as the "forward direction", and the direction of movement of the movable plate 120 during mold opening (e.g. the negative X-axis direction) is referred to as the "reverse direction".

[0048] The ejector 200 is attached to the movable plate 120 and moves forwards and backwards together with the movable plate 120. The ejector 200 comprises one or more ejector rods 210, which eject a molded product from the molded part 800, and a drive mechanism 220, which moves the ejector rod 210 in the directions of movement (the X-axis direction) of the movable plate 120.

[0049] Each ejector rod 210 is arranged in a through-hole of the movable plate 120 to allow forward and backward movement. The front end of the ejector rod 210 contacts an ejector plate 826 of the movable mold 820. The front end of the ejector rod 210 can be connected to or separated from the ejector plate 826.

[0050] The drive mechanism 220, for example, comprises an ejector motor and a motion conversion mechanism that converts the rotary motion of the ejector motor into the linear motion of the ejector rod 210. The motion conversion mechanism includes a spindle shaft and a spindle nut that fits together with the spindle shaft. Balls or rollers can be inserted between the spindle shaft and the spindle nut.

[0051] The ejector 200, controlled by the controller 700, performs an ejection operation. During this operation, the ejector rods 210 are moved forward from a ready position to an ejection position at a set speed to advance the ejector plate 826 for ejecting a molded product. The ejector motor is then driven to move the ejector rods 210 backward at a set speed to return the ejector plate 826 to its initial ready position.

[0052] The position and speed of movement of the ejector rods 210 are detected, for example, by 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 controller 700. An ejector rod position detector, which detects the position of the ejector rods 210, and an ejector rod speed detector, which detects the speed of movement of the ejector rods 210, are not limited to the ejector motor encoder, and general-purpose detectors can be used. (Injection part)

[0053] Unlike the description of the form-closing / clamping part 100 and the ejector 200, in the description of the injection part 300 the direction of movement of a screw 330 during filling (e.g. the negative X-axis direction) is referred to as the "forward direction", and the direction of movement of the screw 330 during metering (e.g. the positive X-axis direction) is referred to as the "reverse direction".

[0054] The injection part 300 is installed on a sliding base 301, and the sliding base 301 is arranged so that it is movable forwards and backwards relative to the injection part frame 920. The injection part 300 is arranged so that it is movable toward and away from the molded part 800. The injection part 300 contacts the molded part 800 to fill the cavity 801 within the molded part 800 with a molding material. The injection part 300 comprises, for example, a cylinder 310 which heats a molding material, a nozzle 320 which is provided at the front end of the cylinder 310, the screw 330 which is arranged in the cylinder 310 in such a way that it is movable and rotatable forwards and backwards, a metering motor 340 which rotates the screw 330, an injection motor 350 which moves the screw 330 forwards and backwards, and a load detector 360 which detects a load transmitted between the injection motor 350 and the screw 330.

[0055] The cylinder 310 heats a molding material that is fed into the interior of the cylinder through a feed port 311. Examples of the molding material include resin. The molding material is, for example, formed into pellets and is fed to the feed port 311 in a solid state. The feed port 311 is located in a rear section of the cylinder 310. A cooler 312, for example a water-cooling cylinder, is provided on the cylindrical outer surface of the rear section of the cylinder 310. First heaters 313, such as a heating band, and first temperature detectors 314 are provided upstream of the cooler 312 on the outer cylindrical surface of the cylinder 310.

[0056] The cylinder 310 is divided into several zones along its axial direction (e.g., in the X-axis direction). Each zone is equipped with the first heater 313 and the first temperature detector 314. A temperature is set for each zone, and the controller 700 controls the first heater 313 so that the temperature detected by the first temperature detector 314 becomes the set temperature.

[0057] The nozzle 320 is located at the front end of the cylinder 310 and is pressed against the molded part 800. A second heater 323 and a second temperature detector 324 are located on the circumference of the nozzle 320. The controller 700 controls the second heater 323 so that the detected temperature of the nozzle 320 matches the set temperature.

[0058] The screw 330 is arranged in the cylinder 310 to be rotatable and move forwards and backwards. As the screw 330 rotates, a molding material is moved forward along the helical groove of the screw 330. The molding material is gradually melted by the heat of the cylinder 310 as it is conveyed forwards. When the molding material, in liquid form, is conveyed forwards on the screw 330 to accumulate in the front part of the cylinder 310, the screw 330 is moved backwards. As the screw 330 moves forwards, the molding material accumulated in liquid form in front of the screw 330 is then injected through the nozzle 320 into the molded part 800.

[0059] A non-return valve ring 331 is attached to a front part of the screw 330 to act as a non-return valve, movable forwards and backwards, preventing the backflow of the molding material from the front to the rear of the screw 330 when the screw 330 is pushed forwards.

[0060] When the screw 330 is moved forward, the backflow prevention ring 331 is pushed backward by the pressure of the molding material in front of the screw 330 to move into a closed position relative to the screw 330 (see Fig. 2), which closes the flow channel of the molding material, thereby preventing the backflow of the molding material accumulated in front of the screw 330.

[0061] When the screw 330 is rotated, the non-return ring 331 is pushed forward by the pressure of the molding material conveyed along the helical groove of the screw 330 to move into an open position relative to the screw 330 (see Fig. 1), which opens the flow channel of the molding material. As a result, the molding material is conveyed forward by the screw 330.

[0062] The backflow prevention ring 331 can be of a rotating type, which rotates together with the screw 330, or of a non-rotating type, which does not rotate together with the screw 330.

[0063] The injection part 300 can contain a drive source that moves the non-return ring 331 forwards and backwards relative to the screw 330 between the open position and the closed position.

[0064] The metering motor 340 rotates the screw 330. The drive source that rotates the screw 330 is not limited to the metering motor 340 and can, for example, be a hydraulic pump.

[0065] The injection motor 350 moves the screw 330 forwards and backwards. A motion conversion mechanism is provided between the injection motor 350 and the screw 330, which converts the rotary motion of the injection motor 350 into the linear motion of the screw 330, and so on. The motion conversion mechanism includes, for example, a spindle shaft and a spindle nut that fits together with the spindle shaft. Balls or rollers may be provided between the spindle shaft and the spindle nut. The drive source that moves the screw 330 forwards and backwards is not limited to the injection motor 350 and can, for example, be a hydraulic cylinder.

[0066] The load detector 360 detects a load transmitted between the injection motor 350 and the screw 330. The detected load is converted into pressure in the control unit 700. The load detector 360 is positioned in the load transmission path between the injection motor 350 and the screw 330 to detect a load applied to it.

[0067] The load detector 360 transmits a signal of the detected load to the controller 700. The load detected by the load detector 360 is converted into a pressure applied between the screw 330 and the molding material and is used to control and monitor a pressure that the screw 330 receives from the molding material, a counter-pressure against the screw 330, a pressure applied by the screw 330 to the molding material, and the like.

[0068] A pressure detector that detects the pressure of a molding material is not limited to the load detector 360, and a more general type can be used. For example, a nozzle pressure sensor or a cavity pressure sensor can be used. The nozzle pressure sensor is located in the nozzle 320. The cavity pressure sensor is located inside the molded part 800.

[0069] The injection unit 300, controlled by the control unit 700, performs processes such as a dosing process, a filling process, and a residence process. The filling process and the residence process can be collectively referred to as the "injection process".

[0070] In the metering process, the metering motor 340 is driven to rotate the screw 330 at a set speed, conveying the molding material forward along the helical groove of the screw 330. This gradually melts the molding material. Once the molding material, in liquid form, has been conveyed forward by the screw 330 to accumulate in the front part of the cylinder 310, the screw 330 is reversed. The rotational speed of the screw 330 is detected using a metering motor encoder 341 or the like. The metering motor encoder 341 detects the rotation of the metering motor 340 and transmits a signal indicating the detection results to the controller 700. A screw speed detector that detects the rotational speed of the screw 330 is not limited to the metering motor encoder 341, and a more general-purpose encoder can be used.

[0071] To limit a sudden reverse movement of the screw 330, the injection motor 350 can be driven during the metering process to apply a set back pressure to the screw 330. This back pressure on the screw 330 is detected, for example, by the load detector 360. When the screw 330 is moved backward into a metering end position, and a predetermined amount of molding material has accumulated in front of the screw 330, the metering process is complete.

[0072] The position and speed of the 330 screw during the metering process are set collectively as a series of adjustment parameters. For example, a metering start position, a speed changeover position, and a metering end position are set. These positions, arranged in this order in reverse from the front, represent the start and end points of the sections for which the speed is set. The speed is set section by section. There can be one or more speed changeover positions. The speed changeover position does not have to be set. Additionally, a back pressure is set for each section.

[0073] During the filling process, the injection motor 350 is driven to move the screw 330 forward at a set speed to fill the cavity 801 within the molded part 800 with the molding material that has accumulated in liquid form in front of the screw 330. The position and speed of the screw 330 are detected, for example, by an 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 to the controller 700. When the position of the screw 330 reaches a set position, the filling process switches to the dwell process (so-called V / P changeover). The position at which the V / P changeover occurs can be referred to as the "V / P changeover position". The set movement speed of the screw 330 can be changed according to the position of the screw 330, time and the like.

[0074] The position and speed of screw 330 during the filling process are set collectively as a series of adjustment parameters. For example, a filling start position (also referred to as the "injection start position"), a speed switching position, and the V / P switching position are set. These positions, arranged in this order in the forward direction from the rear, represent the start and end points of sections for which the speed is set. The speed is set section by section. There can be one or more speed switching positions. The speed switching position does not have to be set.

[0075] The upper limit of the screw pressure 330 is set for each section for which the screw speed 330 is set. The screw pressure 330 is detected by the load detector 360. If the screw pressure 330 is less than or equal to a set pressure, the screw 330 moves forward at a set speed. If the screw pressure 330 exceeds the set pressure, the screw 330 moves forward at a lower speed than the set speed so that the screw pressure 330 remains less than or equal to the set pressure to protect the mold.

[0076] During the filling process, once the screw 330 reaches the V / P switching position, it can be temporarily stopped at the V / P switching position, and the V / P switching can then be performed. Immediately before the V / P switching, the screw 330 can be moved very slowly forward or backward instead of being stopped. A screw position detector, which detects the position of the screw 330, and a screw movement speed detector, which detects the movement speed of the screw 330, are not limited to the injection motor encoder 351 of the injection motor, and general-purpose encoders can be used.

[0077] During the residence process, the injection motor 350 is driven to push the screw 330 forward, maintaining the pressure of the molding material at the front end of the screw 330 (hereinafter also referred to as "residence pressure") at a set pressure and forcing the molding material remaining in the cylinder 310 toward the molded part 800. It is possible to compensate for a lack of molding material due to cooling contraction within the molded part 800. The residence pressure is detected, for example, by the load detector 360. The set value of the residence pressure can be changed according to the time elapsed since the start of the residence process or similar factors. Two or more values ​​can be set for both the residence pressure and the residence time to maintain the residence pressure during the residence process, and the residence pressure and residence time can be set collectively as a set of parameters.

[0078] During the residence process, the molding material in the cavity 801 within the molded part 800 is gradually cooled so that the inlet of the cavity 801 is filled with the solidified molding material when the residence process is complete. This condition, referred to as the "gate seal," prevents the backflow of the molding material from the cavity 801. After the residence process, the cooling process is initiated. During the cooling process, the molding material in the cavity 801 solidifies. The metering process can be performed during the cooling process to shorten the mold cycle time.

[0079] The injection unit 300, which in this embodiment is an inline screw type, can be of a screw pre-plasticizing type. According to the screw pre-plasticizing injection unit, a molding material molten in a plasticizing cylinder is fed to an injection cylinder, and the molding material is injected from the injection cylinder into a molded part. In the plasticizing cylinder, a screw is arranged to be rotatable and immobile in either direction, or a screw is arranged to be rotatable and movable in both directions. In the injection cylinder, a plunger piston is arranged to be movable in both directions.

[0080] Furthermore, the injection part 300, which according to this embodiment is of a horizontal type, in which the axial direction of the cylinder 310 is horizontal, can be of a vertical type, in which the axial direction of the cylinder 310 is vertical. A form-locking / clamping part combined with the injection part 300 of a vertical type can be of a horizontal type or a vertical type. Likewise, a form-locking / clamping part combined with the injection part 300 of a horizontal type can be of a horizontal type or a vertical type. (Movement part)

[0081] In the description of the moving part 400, similar to the description of the injection part 300, the direction of movement of the screw 330 during filling (e.g. the negative X-axis direction) is referred to as the "forward direction", and the direction of movement of the screw 330 during metering (e.g. the positive X-axis direction) is referred to as the "reverse direction".

[0082] The moving part 400 moves the injection part 300 towards and away from the molded part 800. The moving part 400 also presses the nozzle 320 against the molded part 800 to generate nozzle contact pressure. The moving part 400 comprises a hydraulic pump 410, a motor 420 which serves as a drive source, and a hydraulic cylinder 430 which serves as a hydraulic actuator.

[0083] The hydraulic pump 410 has a first port 411 and a second port 412. The hydraulic pump 410, which is a bidirectional rotary pump, reverses the direction of rotation of the motor 420 to draw in hydraulic fluid (e.g., oil) from one of the first ports 411 and the second port 412 and to discharge hydraulic fluid from the other port, thereby generating hydraulic pressure. The hydraulic pump 410 can draw in hydraulic fluid from a tank and discharge hydraulic fluid from one of the first ports 411 and the second port 412.

[0084] Motor 420 causes hydraulic pump 410 to operate. Motor 420 drives hydraulic pump 410 with a direction of rotation and torque corresponding to a control signal from controller 700. Motor 420 can be an electric motor or an electric servo motor.

[0085] The hydraulic cylinder 430 comprises a cylinder body 431, a piston 432, and a piston rod 433. The cylinder body 431 is attached to the injection part 300. The piston 432 divides the interior of the cylinder body 431 into a front chamber 435, which serves as the first chamber, and a rear chamber 436, which serves as the second chamber. The piston rod 433 is attached to the stationary plate 110.

[0086] The front chamber 435 of the hydraulic cylinder 430 is connected to the first port 411 of the hydraulic pump 410 via a first flow channel 401. The hydraulic fluid discharged from the first port 411 is supplied to the front chamber 435 via the first flow channel 401 to push the injection element 300 forward. The injection element 300 is moved forward to press the nozzle 320 against the stationary form 810. The front chamber 435 acts as a pressure chamber, generating the nozzle contact pressure of the nozzle 320 with the pressure of the hydraulic fluid supplied by the hydraulic pump 410.

[0087] The rear chamber 436 of the hydraulic cylinder 430 is connected to the second port 412 of the hydraulic pump 410 via a second flow channel 402. The hydraulic fluid discharged from the second port 412 is supplied to the rear chamber 436 of the hydraulic cylinder 430 via the second flow channel 402 to push the injection element 300 backward. The injection element 300 is moved backward to separate the nozzle 320 from the stationary form 810.

[0088] According to this embodiment, the moving part 400 comprises the hydraulic cylinder 430. However, the present disclosure is not limited to this. Instead of the hydraulic cylinder 430, for example, an electric motor and a motion conversion mechanism can be used, which converts the rotary motion of the electric motor into the linear motion of the injection part 300. (Steering)

[0089] The controller 700, which is built, for example, from a computer, comprises a central processing unit (CPU) 701, a storage medium 702, such as a memory, an input / output interface (I / F) 703, and an output / output interface (I / F) 704, as shown in Fig. 1 and Fig. Figure 2 illustrates this. The controller 700 performs various control functions by instructing the CPU 701 to execute one or more programs stored in the memory medium 702. Furthermore, the controller 700 receives an external signal at the input interface 703 and sends a signal externally at the output interface 704.

[0090] The 700 control system repeatedly produces a molded product by repeatedly executing operations such as the dosing process, the mold closing process, the pressurization process, the mold clamping / closing process, the filling process, the dwell process, the cooling process, the pressure release process, the mold opening process, and the ejection process. A series of operations to obtain a molded product, for example, the operations from the start of one dosing process to the start of the next, can be referred to as a "shot" or "mold cycle." Furthermore, the time required for a shot can be referred to as the "mold cycle time" or "cycle time."

[0091] A mold cycle, for example, includes the dosing process, the mold closing process, the pressurization process, the mold clamping / closing process, the filling process, the dwell process, the cooling process, the pressure release process, the mold opening process, and the ejection process in that order. The order here refers to the sequence in which the processes are started. The filling process, the dwell process, and the cooling process are executed during the mold clamping / closing process. The start of the mold clamping / closing process can coincide with the start of the filling process. The completion of the pressure release process coincides with the start of the mold opening process.

[0092] Several processes can be executed simultaneously to shorten the cycle time. For example, the dosing process can be performed during the cooling process of the preceding mold cycle or during the mold closing / clamping process. In such a case, the mold closing process can be performed at the start of the mold cycle. Furthermore, the filling process can be started during the mold closing process. Additionally, the ejection process can be started during the mold opening process. If an on / off valve is provided that opens and closes the flow path of nozzle 320, the mold opening process can be started during the dosing process. This is because, even if the mold opening process is started during the dosing process, no mold material will exit nozzle 320 as long as the on / off valve closes the flow path of nozzle 320.

[0093] A mold cycle can include one or more processes that differ from the dosing process, the mold closing process, the pressurizing process, the mold closing / clamping process, the filling process, the dwell process, the cooling process, the pressure relief process, the mold opening process, and the ejection process.

[0094] For example, before the start of the dosing process, a pre-vacuum process can be performed after the completion of the dwell process to move the screw 330 backwards into a preset dosing start position. This makes it possible to reduce the pressure of the molding material accumulated in front of the screw 330 before the start of the dosing process and to prevent a sudden backward movement of the screw 330 at the start of the dosing process.

[0095] Furthermore, before the filling process begins, a post-dosing vacuuming operation can be performed to move the screw 330 backwards into a preset filling start position (also referred to as the "injection start position"). This reduces the pressure of the molding material accumulated in front of the screw 330 before the filling process begins and prevents the molding material from escaping the nozzle 320 before the filling process starts.

[0096] The controller 700 is connected to an operating device 750, which receives input from a user, and a display device 760, which displays a screen. The operating device 750 and the display device 760 can, for example, be constructed as a single unit, consisting of a touchscreen 770. The touchscreen 770, serving as the display device 760, displays a screen below the controller 700. For example, information such as the settings of the injection molding machine 10 and its current status can be displayed on the touchscreen 770. The touchscreen 770 can also display operating elements such as buttons and input fields for receiving user input.The touchscreen 770, which serves as the operating device 750, recognizes user input on the screen and sends a corresponding signal to the controller 700. This allows the user, for example, to enter settings (including setpoints) for the injection molding machine 10 by operating the controls provided on the screen while reviewing the information displayed. Furthermore, the user can cause the injection molding machine 10 to perform the corresponding operations by operating the controls provided on the screen. These operations of the injection molding machine 10 can include, for example, the actions (including stopping) of the mold clamping / closing part 100, the ejector 200, the injection part 300, the movement part 400, and the like.Furthermore, the processes of the injection molding machine 10 can, for example, include switching the screen that is displayed on the touchscreen 770, which serves as a display device 760.

[0097] The operating device 750 and the display device 760 of this embodiment, which are described as being integrated into the touchscreen 770, can be provided separately. Furthermore, two or more operating devices 750 can be provided. The operating device 750 and the display device 760 are arranged on the operating side (negative side in the Y-axis direction) of the form-closing / clamping part 100 (more specifically, the stationary plate 110). (Details about the injection unit)

[0098] Next, examples of cylinder 310 and screw 330 will be given with reference to Fig. 3 described. The injection part 300 comprises, for example, the cylinder 310, which heats a molding material, and the screw 330 arranged in the cylinder 310. The screw 330 is an example of a rotating element. The injection part 300 rotates the screw 330 to inject the molding material along the helical groove formed in the screw 330 from upstream to downstream (in Fig. 3 from right to left). In the following, "upstream" can be referred to as "backwards", and "downstream" can be referred to as "forwards".

[0099] The cylinder 310 is divided into several (e.g., five) zones Z0 to Z4 in the axial direction (e.g., in the X-axis direction) of the cylinder 310. The most upstream zone, Z0, is equipped with a cooler 312, and each of the other zones, Z1 to Z4, is equipped with the first heater 313 and the first temperature detector 314. A temperature is set for each of the zones Z0 to Z4. The number of zones is not limited as long as there are two or more. The number of zones is not limited to five.

[0100] The controller 700 regulates the temperature of a coolant supplied by a coolant supply 315 to the cooler 312, so that the actual temperature of zone Z0 becomes the set temperature. The cooler 312 cools a feed port 311 for the molding material, thereby suppressing a phenomenon known as bridging. Bridging is a phenomenon in which resin pellets forming the molding material melt, causing the feed port 311 to become clogged. The cooler 312 is, for example, a water-cooling cylinder. The cooler 312 or the coolant supply 315 may contain a temperature detector. The cooler 312 is an example of the temperature control device.

[0101] The controller 700 detects the actual temperature of each of zones Z1 to Z4 using the first temperature detector 314 and individually controls an output of the first heater 313 for each of zones Z1 to Z4, so that the actual temperature detected by the first temperature detector 314 becomes the set temperature. The multiple first heaters 313 can have the same or different configurations. For example, the first heater 313 is a heating band. The first heater 313 is an example of a temperature setting device.

[0102] The power output of the first heater 313 is specified, for example, as a percentage (%) of the power supply time per unit of time. The higher the percentage of the power supply time, the higher the power output of the first heater 313. Although not illustrated, if several first heaters 313 are provided in a single zone, the percentages of the power supply times of the several first heaters 313 are controlled to be equal. Similarly, although not shown, several first temperature detectors 314 can be provided in a single zone. The number of zones, the number of first heaters 313, and the number of first temperature detectors 314 need not be identical.

[0103] The nozzle 320 is located at the front end of the cylinder 310. The nozzle 320 is pressed against the molded part 800 (see Fig. 1 and Fig. 2) and injects the previously melted molding material into the molded part 800. The second heater 323 and the second temperature detector 324 are provided on the circumference of the nozzle 320. The second heater 323 and the second temperature detector 324 are located in zone Z5.

[0104] The controller 700 detects the actual temperature of zone Z5 using the second temperature detector 324 and regulates the power of the second heater 323 so that the actual temperature detected by the second temperature detector 324 becomes the set temperature. The second heater 323 is, for example, a heating coil. The power of the second heater 323 is specified, for example, as a percentage (%) of a current supply time per unit of time.

[0105] Similar to the cylinder 310, the nozzle 320 can also be divided into several zones along the X-axis. A second heater 323 and a second temperature detector 324 are provided in each zone. In this case, the controller 700 regulates the power output of the second heater 323 individually for each zone. The multiple second heaters 323 can have the same or different configurations.

[0106] The screw 330 is arranged in the cylinder 310 to be rotatable and move forwards and backwards. When the metering motor 340 rotates the screw 330, the molding material is conveyed forwards along the helical groove of the screw 330. The molding material is gradually melted by the heat of the cylinder 310 as it is conveyed forwards.

[0107] When the molding material is conveyed forward in liquid form on the screw 330 to accumulate at the front of the cylinder 310, the screw 330 is moved backward. Then, when the injection motor 350 moves the screw 330 forward, the molding material in liquid form, which has accumulated in front of the screw 330, is injected through the nozzle 320 into the molded part 800.

[0108] Next, an example of screen 771 is shown in relation to the set temperature of cylinder 310 with reference to Fig. 4 described. The screen 771 includes input elements 772 to 777, via which the target temperature is entered. A user operates the control device 750 (see Fig. 1 and Fig. 2) while checking screen 771, the target temperature is entered into input fields 772 to 777. Input fields 772 to 777 display the entered target temperature.

[0109] A target temperature T0ref for zone Z0 is entered into input unit 772. The controller 700 regulates the temperature of the coolant supplied from coolant supply 315 to cooler 312 such that the actual temperature T0det of zone Z0 becomes the target temperature. The coolant flow rate can be set so that the coolant temperature does not change significantly before entering and after exiting cooler 312. The actual temperature T0det of zone Z0 is maintained at the coolant temperature. Therefore, it is possible to detect the actual temperature T0det of zone Z0 by monitoring the coolant temperature.

[0110] The target temperatures T1ref to T4ref for zones Z1 to Z4 are entered into input fields 773 to 776. The target temperature T1ref for zone Z1 is entered into input field 773, the target temperature T2ref for zone Z2 is entered into input field 774, the target temperature T3ref for zone Z3 is entered into input field 775, and the target temperature T4ref for zone Z4 is entered into input field 776. The controller 700 regulates the first heaters 313 so that the actual temperatures T1det to T4det become the target temperatures T1ref to T4ref.

[0111] A target temperature T5ref for zone Z5 is entered into input unit 777. The controller 700 regulates the second heater 323 so that the actual temperature T5det of zone Z5 becomes the target temperature T5ref. Similar to the cylinder 310, the nozzle 320 can also be divided into several zones in the X-axis direction, and the respective target temperatures of the several zones can be entered.

[0112] Screen 771 contains display sections 782 to 787, which show the actual temperatures T0det to T5det of zones Z0 to Z5. By checking screen 771, the user can verify the difference between the actual temperature and the target temperature for each of zones Z0 to Z5. Display section 782 shows the actual temperature T0det of zone Z0, display section 783 shows the actual temperature T1det of zone Z1, display section 784 shows the actual temperature T2det of zone Z2, display section 785 shows the actual temperature T3det of zone Z3, display section 786 shows the actual temperature T4det of zone Z4, and display section 787 shows the actual temperature T5det of zone Z5.

[0113] Next, an example of the snail 330 will be given with reference to Fig. As described in section 5, the screw 330 comprises a rotating shaft 332 and a thread 333, which is arranged helically around the rotating shaft 332. A helical groove 334 is formed along the thread 333. When the metering motor 340 rotates the screw 330, the molding material is conveyed from upstream to downstream along the helical groove 334.

[0114] For example, screw 330 comprises, from upstream to downstream, a feed zone X1, a compression zone X2, and a metering zone X3. The feed zone X1 is an area where the molding material is conveyed forward in pellet form while retaining a solid phase. The compression zone X2 is an area where the molding material is compressed and conveyed forward while being melted. The metering zone X3 is an area where the molten molding material is conveyed forward.

[0115] The spiral groove 334 is deep in the feed zone X1 and shallow in the metering zone X3. The spiral groove 334 becomes shallower in the compression zone X2 as it progresses. The depth of the groove 334 is constant in both the feed zone X1 and the metering zone X3. The ratio (D1 / D3) of the groove depth D1 in the feed zone X1 to the groove depth D3 in the metering zone X3 is also referred to as the compression ratio.

[0116] The configuration of the screw 330 is not subject to any special restrictions. For example, the depth of the groove 334 can be constant from the front end to the rear end of the screw 330.

[0117] Next, the temperature of the molding material in cylinder 310 will be measured with reference to Fig. 3 described. The temperature of the molding material in the cylinder 310 is primarily controlled by the set temperature of the cylinder 310, but can be altered due to shear-induced heat generation caused by the rotation of the screw 330. Shear-induced heat generation occurs through the application of a shear stress to the molding material. A lower setpoint temperature of the cylinder 310 results in a lower temperature of the molding material, a higher viscosity of the molding material, a higher shear stress, and a greater degree of shear-induced heat generation.

[0118] Shear-induced heat generation is common in compression zone X2. This is because the groove 334 in compression zone X2, where the shear stress is high, becomes shallower from upstream to downstream. The shear-induced heat generation increases the temperature of the mold material. Therefore, the greater the degree of shear-induced heat generation leads to a higher temperature of the mold material. Unlike the output of the first heater 313, the degree of shear-induced heat generation is not readily controllable.

[0119] To control the temperature of the molding material to a desired temperature, it is therefore preferred to reduce the extent of shear-induced heat generation as much as possible. The temperature of the molding material is controlled to a desired temperature due to the occurrence of molding defects, for example, if the temperature of the molding material is too high. A higher frequency of molding defects leads to a higher maintenance frequency of the molded part 800.

[0120] Molding defects that occur when the molding material temperature is too high include, for example, gas burning, black spot formation, and black streak formation. Gas burning is a phenomenon where the molding material chars due to heat generated by gas compression in the cavity 801 of the molded part 800. This gas compression occurs when the molding material flows into the cavity 801. If the molding material temperature is too high, the material thermally decomposes, producing a large amount of gas, which causes gas burning. Black spot formation is a phenomenon where black spots appear in molded products. Black streak formation is a phenomenon where black streaks appear in molded products. If the molding material temperature is too high, the material thermally damages it, resulting in black spots or streaks.

[0121] The forming defect also occurs because the temperature of the molding material is not necessarily identical to the temperature of the cylinder 310.

[0122] In recent years, bioplastics have been considered as a molding material for injection molding. Bioplastics is a collective term for biomass plastics and biodegradable plastics. Biomass plastics are plastics whose raw materials are biological resources such as plants. Biodegradable plastics are plastics that eventually break down into carbon dioxide and water through the action of microorganisms. One example of a bioplastic used for injection molding is polylactic acid (PLA). PLA is both a biomass plastic and a biodegradable plastic.

[0123] Bioplastics are prone to thermal degradation. Therefore, the temperature of cylinder 310 can be set to be low. However, if the set temperature of cylinder 310 is too low, abnormal heat generation occurs due to shearing of the molding material, which causes molding defects. Shearing of the molding material occurs when the material is conveyed from upstream to downstream along the helical groove 334 formed in the screw 330. One cause of abnormal heat generation due to shearing is, for example, insufficient heating on the upstream side.

[0124] The temperature of cylinder 310 can also be set low if the mold material is a petroleum-based plastic. Setting the temperature low is also done to shorten the mold cycle time (especially the cooling step time). If the set temperature of cylinder 310 is too low, abnormal heat generation will inevitably occur on the downstream side due to shearing, causing mold defects.

[0125] If abnormal heat generation occurs due to shearing, and as a result the temperature of cylinder 310 cannot be adequately controlled, interruption of a molding cycle and maintenance work are required. Even if the difference between the set temperature and the actual temperature is approximately 1°C to 2°C, or even less than 1°C, it may be necessary to take measures to avoid interrupting a molding cycle. Therefore, abnormal heat generation due to shearing is a cause of molding defects that is easily overlooked by an insufficiently trained operator.

[0126] If the difference between the set temperature and the actual temperature occurs for a reason other than abnormal heat generation due to shear, the controller 700 can individually regulate the output of the first heater 313 for each of the zones Z1 to Z4, as described above. Specifically, if there is a positive temperature difference, the use of the first heater 313 is interrupted, thereby bringing the actual temperature closer to the set temperature by heat output. If there is a negative temperature difference, heating is carried out by the first heater 313, thereby bringing the actual temperature closer to the set temperature.However, if heat generation due to shear is abnormal and there is a positive temperature difference, the condition of injection molding machine 10 deteriorates to such an extent that a molding cycle requires interruption and maintenance, even if the temperature is lowered to eliminate the temperature difference. This cannot be remedied by conventional feedback control. Therefore, if a positive temperature difference exists, control is required to increase the temperature on the upstream side. Consequently, if an insufficiently trained operator continues with feedback control, there is a risk that the condition of injection molding machine 10 will deteriorate to such an extent that a molding cycle requires interruption and maintenance.

[0127] In light of the above, the controller 700 of this embodiment is configured to detect abnormal heat generation due to shearing of the mold material based on the actual temperature of a predetermined zone. The predetermined zone is the middle zones Z1 to Z3, excluding the most upstream zone Z0 and the most downstream zone Z4. The predetermined zone is typically zone Z2 or Z3, which overlaps with compression zone X2. Abnormal heat generation due to shearing is a cause of molding defects that is easily overlooked by an insufficiently trained operator. According to this embodiment, the controller 700 detects abnormal heat generation due to shearing and can suppress molding defects.

[0128] Next, an example of the components of the 700 control unit will be given with reference to Fig. 7 described. The control unit 700 is an example of the management device. In this embodiment, the management device is part of the injection molding machine 10, but it can be provided separately from the injection molding machine 10. The management device is, for example, a computer. The management device can be a host computer that manages several injection molding machines 10.

[0129] The in Fig. The six functional blocks shown are conceptual and do not need to be physically configured as depicted. All or some of the functional blocks can be functionally or physically distributed, or integrated in desired parts. Processing functions executed within the functional blocks are carried out, in whole or in part, as desired, by one or more programs running on a CPU. Alternatively, the functional blocks can be implemented as hardware using wired logic.

[0130] As in Fig. As shown in Figure 6, the controller 700 comprises, for example, a temperature setting device 711, an abnormal heat generation detector 712, a notification controller 713, an approval confirmation part 714, a setting temperature change part 715, and a prior confirmation part 716. The temperature controller 711 is configured to regulate the multiple first heaters 313 so that the actual temperatures T1det to T4det each become the set temperatures T1ref to T4ref. The abnormal heat generation detector 712 is configured to detect abnormal heat generation due to shearing of the mold material based on the actual temperature of a predetermined zone. The notification controller 713 is configured to provide a notification to a user of the injection molding machine 10 to confirm whether or not the user approves a change in the set temperature upon detection of abnormal heat generation.The approval confirmation part 714 is configured to confirm user approval of the notification. The setting temperature change part 715 is configured to increase the set temperature of a zone upstream of the zone where abnormal heat generation is detected. The prior confirmation part 716 is configured to obtain a selection beforehand as to whether the user of injection molding machine 10 wishes to receive a notification confirming their approval for changing the set temperature upon detection of abnormal heat generation. The components mentioned above are described below.

[0131] The abnormal heat generation detector 712 detects abnormal heat generation due to shear of the mold material based on the actual temperature of the specified zone. Abnormal heat generation due to shear is a cause of molding defects that can be overlooked by an insufficiently trained user. Since the abnormal heat generation detector 712 detects abnormal heat generation due to shear, molding defects can be suppressed according to this embodiment.

[0132] There is no specific restriction regarding the zone in which abnormal heat generation is to be detected. For example, the zone to be detected can be a zone that overlaps the compression zone X2 of the screw 330 in a metering step (e.g., zone Z2 or Z3). This is because the extent of shear-induced heat generation in compression zone X2 is high. The number of zones in which abnormal heat generation is to be detected is one or more.

[0133] The abnormal heat generation detector 712, for example, detects abnormal heat generation based on the difference ΔT2 (ΔT2 = T2det - T2ref) between the actual temperature T2det and the set temperature T2ref in the predetermined zone (e.g., zone Z2). If ΔT2 exceeds zero, the temperature controller 711 reduces the power of the first heater 313 so that ΔT2 becomes zero. Even if ΔT2 does not become zero, abnormal heat generation is still considered to be occurring. The abnormal heat generation detector 712 determines, for example, the occurrence of abnormal heat generation when ΔT2 is greater than or equal to a threshold value.

[0134] The abnormal heat generation detector 712 can detect abnormal heat generation based on the actual temperature T2det and the set temperature T2ref. Instead of the difference between the actual temperature T2det and the set temperature T2ref, the abnormal heat generation detector 712 can detect abnormal heat generation based on a ratio between the actual temperature T2det and the set temperature T2ref. The abnormal heat generation detector 712 can also detect abnormal heat generation based on a function, where the actual temperature T2det and the set temperature T2ref are variables.

[0135] The abnormal heat generation detector 712 can detect abnormal heat generation, for example, based on a change in the actual temperature T2det in the predetermined zone Z2 during the metering step. During the metering step, the screw 330 rotates. The rotation of the screw 330 applies a shear stress to the mold material, resulting in shear-induced heat generation. Consequently, the actual temperature T2det increases. The abnormal heat generation detector 712 determines the occurrence of abnormal heat generation, for example, when the change in the actual temperature T2det during the metering step is higher than or equal to a threshold value.

[0136] The first temperature detectors 314 include, for example, a first detector located upstream in a direction in which the molding material is conveyed (e.g., a first temperature detector 314A), a second detector located downstream of the first detector (e.g., a first temperature detector 314B or 314C), and a third detector located downstream of the second detector (e.g., a first temperature detector 314D).

[0137] The abnormal heat generation detector 712 detects abnormal heat generation due to shearing of the mold material based on the actual temperature detected by the second detector. The first detector is the first temperature detector 314A, which is closest to the first heater 313A located furthest upstream among the first heaters 313A to 313D. The third detector is the first temperature detector 314D, which is closest to the first heater 313D located furthest downstream among the first heaters 313A to 313D.

[0138] The temperature adjustment unit 715 increases the set temperature T1ref of a zone (e.g., zone Z1) upstream of a zone (e.g., zone Z2) where abnormal heat generation has been detected by the abnormal heat generation detector 712. The temperature control unit 711 regulates the first heater 313 based on the set temperature T1ref after the change. Thus, after sufficient heating of the mold material on the upstream side, the mold material can be conveyed to the downstream side. Consequently, it is possible to suppress the occurrence of excessive shear stress due to insufficient heating, to suppress excessive shear-induced heat generation, and to suppress molding defects.

[0139] The zone in which the set temperature T1ref is to be increased can be any zone, as long as it is upstream of the zone where abnormal heat generation was detected. The zone in which the set temperature T1ref is to be increased can be zone Z0, where the cooler 312 is located. Preferably, however, the zone is zone Z1, which is furthest upstream from zones Z1 to Z4, where the first heater 313 is located. This makes it possible to suppress the formation of a bridge of the mold material at the feed port 311 and to suppress abnormal heat generation due to shear.

[0140] The amount by which the set temperature T1ref is to be changed can be determined by reading previously experimentally determined values ​​stored in the storage medium 702, or it can be determined in accordance with ΔT2. A larger ΔT2 indicates a greater degree of shear-induced heat generation. If ΔT2 is larger, the amount by which the set temperature T1ref is to be changed can be greater. The amount by which the set temperature T1ref is to be changed can be determined in such a way as to avoid thermal deterioration of the mold material.

[0141] The notification controller 713 provides a notification to the user of injection molding machine 10 to confirm whether or not the user approves a change to the set temperature after detection of abnormal heat generation and before increasing the set temperature. To help the user easily determine whether to approve the change to the set temperature, the notification controller 713 can additionally notify the user of (A) the zone in which abnormal heat generation was detected, (B) the zone in which the set temperature is to be changed, (C) the set temperature after the change, or any combination thereof. The notification is delivered using an image, sound, or both.

[0142] For example, the notification control 713 displays one in Fig. The screen 791 shown on the display device 760 is displayed. The screen 791 contains an input element 792. The selection of whether or not the user approves the change in the set temperature is entered into the input element 792. The user of the injection molding machine 10 enters their selection into the input element 792 by operating the control device 750 while monitoring the screen 791.

[0143] Alternatively, the notification controller 713 can send a command to a portable device of the user of the injection molding machine 10 to display the in Fig. The selection shown on screen 791 is transferred to the portable device. The user enters their selection into the input part 792 by operating the portable device while checking screen 791. The portable device transmits the selection entered into the input part 792 to the injection molding machine 10.

[0144] Approval confirmation part 714 confirms the user's approval. For example, approval confirmation part 714 receives the selection input in input part 792, thereby confirming the user's approval. Approval confirmation part 714 determines that no user approval has been received, at least until the selection input in input part 792 is received.

[0145] The 715 temperature adjustment unit can increase the set temperature in response to user confirmation. Until user confirmation, the 700 controller maintains the set temperature without increasing it. This prevents the 715 temperature adjustment unit from changing the set temperature without the user's knowledge.

[0146] The temperature adjustment unit 715 can increase the set temperature without user confirmation. Specifically, if the abnormal heat generation detector (712) detects abnormal heat generation, the temperature adjustment unit (715) can immediately increase the set temperature without the notification controller (713) providing a notification to confirm whether the user has approved the temperature change. This immediate increase in the set temperature allows for the immediate correction of molding defects. This helps avoid the production of a large number of rejects and suppresses wasteful molding material consumption.

[0147] If the temperature change control unit 715 increases the set temperature immediately after the abnormal heat generation detector 712 has detected abnormal heat generation, the notification controller 713 can provide the user of the injection molding machine 10 with a notification of the temperature change to alert the user. The timing of the notification can be before or after the temperature change.

[0148] If the setting temperature change part 715 increases the setting temperature immediately after the abnormal heat generation detector 712 has detected the abnormal heat generation, the notification control 713 can notify the user, in addition to the change in the setting temperature, of (A) the zone in which the abnormal heat generation was detected, (B) the zone in which the setting temperature is to be changed, (C) the setting temperature after change, or any combination thereof.

[0149] The prior confirmation part 716 is configured to allow the user of injection molding machine 10 to select whether or not they wish to receive a notification confirming their approval to change the set temperature after detection of abnormal heat generation. Whether the set temperature should be changed immediately after detection of abnormal heat generation can be determined prior to the detection of the abnormal heat generation.

[0150] For example, the previous confirmation part 716 shows the in Fig. The screen 771 shown on the display device 760 is displayed. The screen 771 contains an input element 779. A selection regarding whether the user's approval of the injection molding machine 10 needs to be confirmed (e.g., whether the set temperature is to be changed automatically) can be entered into the input element 779. The user of the injection molding machine 10 enters their selection into the input element 779 by operating the control device 750 while checking the screen 771. The preceding confirmation element 716 confirms the user's intention by entering the selection into the input element 779.

[0151] Alternatively, the previous confirmation part 716 can send a command to a portable device of the user of the injection molding machine 10 to display the in Fig. The selection shown on screen 771 is transferred to the portable device. The user enters their selection into input part 779 by operating the portable device while checking screen 771. The portable device transmits the selection entered into input part 779 to the injection molding machine 10. The preceding confirmation part 716 confirms the user's intention by entering the selection into input part 779.

[0152] Although the temperature setting change part 715 changes the setting temperature in this embodiment, the user of the injection molding machine 10 can change the setting temperature while operating the machine. Fig. 4 shown on screen 771. In this case, if the abnormal heat generation detector (712) has detected the abnormal heat generation, the notification controller (713) can simply provide the user of the injection molding machine 10 with a notification of the occurrence of the abnormal heat generation, and there is no need to provide a notification to confirm whether the user approves a change to the set temperature or not.

[0153] If the user of injection molding machine 10 changes the set temperature while operating the machine, Fig. As shown in screen 771, the notification control 713 can additionally notify the user of (A) the zone in which abnormal heat generation was detected, (B) the zone in which the set temperature needs to be changed, (C) the set temperature after the change, or any combination thereof, so that the user can easily determine whether the set temperature needs to be changed. This can increase usability for a less experienced user.

[0154] Although the abnormal heat generation detector 712 of this embodiment detects abnormal heat generation based on the actual temperature of the predetermined zone of the cylinder 310, the abnormal heat generation detector 712 can detect abnormal heat generation based on an actual torque of the screw 330. A torque detector 361 (see Fig.3) is configured to detect the actual torque of the screw 330 during the metering step. A higher actual torque leads to higher shear stress and a greater degree of shear-induced heat generation. The abnormal heat generation detector 712 determines the occurrence of abnormal heat generation when, for example, the actual torque is greater than or equal to a threshold value.

[0155] If the abnormal heat generation detector (712) detects abnormal heat generation based on the actual torque, the temperature adjustment part 715 increases the set temperature of the predetermined zone. The zone in which the set temperature is to be increased can be zone Z0, where the cooler 312 is located. Preferably, however, the zone is zone Z1, which is the most upstream of zones Z1 to Z4, where the first heater 313 is located.

[0156] If the abnormal heat generation detector 712 detects abnormal heat generation based on the actual torque, the notification controller (713) can provide a notification to the user of the injection molding machine (10) to confirm whether or not the user approves a change to the set temperature. If the approval confirmation part 714 confirms user approval, the setting temperature change part 715 can increase the set temperature.

[0157] The prior confirmation part 716 can receive a selection as to whether the user of the injection molding machine 10 wishes to receive a notification confirming his or her approval to change the set temperature when the abnormal heat generation detector 712 has detected abnormal heat generation based on the actual torque.

[0158] Although the embodiments of the control device for the injection molding machine, the injection molding machine, and the control method for the injection molding machine according to the present disclosure have been described above, the present disclosure is not limited to the embodiments described above and the like. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the stated claims. These naturally fall within the technical scope of the present disclosure. REFERENCE MARK LIST 10 injection molding machines 310 cylinders 312 Radiator (temperature control device) 313 First heater (temperature control device) 314 first temperature detector (temperature detector) 700 Control (administrative device)

Claims

[1] Management device (700) for an injection molding machine (10) comprising a cylinder (310) divided into zones (Z1-Z4) from upstream to downstream along a direction in which a molding material is conveyed, a heater (313) provided in each of the zones (Z1-Z4), and a temperature detector (314) configured to detect an actual temperature in each of the zones (Z1-Z4), wherein the management device (700) is configured, in response to a quantity derived from the actual temperature of a predetermined zone (Z2, Z3) and a temperature set for the predetermined zone (Z2, Z3) exceeding a predetermined value, to reduce the power of the heater (313) provided in the predetermined zone (Z2, Z3), wherein the predetermined zone (Z2, Z3) is one of the zones (Z1-Z4) except for the most upstream zone (Z1) and the most downstream zone (Z4), and in response to the fact that the size continues to exceed the predetermined value after reducing the power of the heater (313) provided in the predetermined zone (Z2, Z3), to determine that abnormal heat generation is occurring in the predetermined zone (Z2, Z3) due to shearing of the mold material, and to increase a temperature set for a zone upstream of the predetermined zone (Z2, Z3) below zones (Z1-Z4). [2] Administrative device (700) according to claim 1, wherein the management device (700) is configured to provide a notification to a user of the injection molding machine (10) to confirm whether the user approves that the temperature set for the zone upstream of the predetermined zone (Z2, Z3) is changed after the occurrence of abnormal heat generation has been detected and before the temperature set for the zone upstream of the predetermined zone (Z2, Z3) is increased, and to increase the temperature set for the zone upstream of the predetermined zone (Z2, Z3) in response to the confirmation that the user allows the change to the temperature set for the zone upstream of the predetermined zone (Z2, Z3). [3] Management device (700) for an injection molding machine (10) comprising a cylinder (310) divided into zones (Z1-Z4) from upstream to downstream along a direction in which a molding material is conveyed and configured to heat the molding material therein, a rotary element (330) configured to rotate in the cylinder (310) and convey the molding material from upstream to downstream, heaters (313) each configured to set a temperature of the cylinder (310), and temperature detectors (314) each configured to detect an actual temperature of the cylinder (310), wherein the zones (Z1-Z4) comprise a first zone, a second zone downstream of the first zone in the direction in which the molding material is conveyed, and a third zone downstream of the second zone in the direction in which the molding material is fed, the heaters (313) comprise a first heater provided in the first zone, a second heater provided in the second zone, and a third heater provided in the third zone, the temperature detectors (314) include a first detector provided in the first zone, a second detector provided in the second zone, and a third detector provided in the third zone, and the management device (700) is configured, In response to a value derived from the actual temperature of the second zone, as detected by the second temperature detector, and a temperature set for the second zone exceeding a predetermined value, the power output of the second heater is reduced, and In response to the fact that the size continues to exceed the predetermined value after reducing the power of the second heater, it was determined that abnormal heat generation is occurring in the second zone due to shearing of the mold material, and a temperature set for the first zone was increased. [4] Injection molding machine (10), comprising: the administrative device (700) according to one of claims 1 to 3; the cylinder (310); the heaters (313); and the temperature detectors (314). [5] Management method for an injection molding machine (10) comprising a cylinder (310) divided into zones (Z1-Z4) from upstream to downstream along a direction in which a molding material is conveyed, a heater (313) provided in each of the zones (Z1-Z4) and a temperature detector (314) configured to detect an actual temperature in each of the zones (Z1-Z4), wherein the management method comprises: in response to a quantity derived from the actual temperature of a predetermined zone (Z2, Z3) and a temperature set for the predetermined zone (Z2, Z3) exceeding a predetermined value, reduction of the power of the heater (313) provided in the predetermined zone (Z2, Z3), wherein the predetermined zone (Z2, Z3) is one of the zones (Z1-Z4) except for the most upstream zone (Z1) and the most downstream zone (Z4), and in response to the fact that the size continues to exceed the predetermined value after reducing the power of the heater (313) provided in the predetermined zone (Z2, Z3), finding that abnormal heat generation is occurring in the predetermined zone (Z2, Z3) due to shearing of the mold material, and increasing a temperature set for a zone upstream of the predetermined zone (Z2, Z3) below the zones (Z1-Z4).

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