Control device for injection molding machine, injection molding machine, and method for controlling injection molding machine

Abstract

To provide a technique for preventing a mold device from opening due to a filling pressure of a molding material when clamping a mold.SOLUTION: There is provided a control device for an injection molding machine, wherein, when a mold device having a fixed mold and a movable mold is clamped, a molding material is filled into each of a first cavity space and a second cavity space which are separately formed between the fixed mold and the movable mold. The control device, when clamping the mold, provides an interval between a first peak timing at which a filling pressure for filling the first cavity space with the molding material reaches a maximum value and a second peak timing at which the filling pressure for filling the second cavity space with the molding material reaches a maximum value.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a control device for an injection molding machine, an injection molding machine, and a control method for an injection molding machine. [Background technology]

[0002] The two-color injection molding machine of Patent Document 1 includes a clamping device installed on a machine stand and a pair of injection devices installed side by side. The clamping device includes a fixed platen fixed to the middle of the machine stand, a support platen fixed to an end of the machine stand, four tie bars installed between the support platen and the fixed platen, a movable platen slidably mounted on each tie bar, and a clamping cylinder for moving the movable platen forward and backward. A rotating platen is arranged so as to overlap with the front surface of the movable platen (the surface facing the fixed platen), and two movable dies are attached to the front surface of the rotating platen. Meanwhile, two fixed dies are attached to the rear surface of the fixed platen (the surface facing the rotating platen). Every time the rotating platen rotates 180°, the combination of the movable and fixed dies that are fitted together changes.

[0003] The molding die of Patent Document 2 simultaneously forms a first cavity space for molding the first division, a second cavity space for molding the second division, and a third cavity space for welding the first division and the second division. This molding die has a first slide die and a second slide die. The first slide die has, from top to bottom, a first male die part, a second female die part, a first female die part, and a second male die part, in this order, on a surface facing the second slide die. Meanwhile, the second slide die has, from top to bottom, a second male die part, a first female die part, a second female die part, and a first male die part, in this order, on a surface facing the first slide die.

[0004] According to Patent Document 2, when the first slide mold is in an upper position and the second slide mold is in a lower position, when the molds are clamped, a first cavity space, a third cavity space, and a second cavity space are formed in this order from the top to the bottom. The first cavity space is formed between the second female mold part of the first slide mold and the second male mold part of the second slide mold. The third cavity space is formed between the first female mold part of the first slide mold and the first female mold part of the second slide mold. The second cavity space is formed between the second male mold part of the first slide mold and the second female mold part of the second slide mold.

[0005] According to Patent Document 2, when the first slide mold is in a lower position and the second slide mold is in an upper position, when the mold is clamped, the second cavity space, the third cavity space, and the first cavity space are formed in this order from the top to the bottom. The second cavity space is formed between the first male mold part of the first slide mold and the first female mold part of the second slide mold. The third cavity space is formed between the second female mold part of the first slide mold and the second female mold part of the second slide mold. The first cavity space is formed between the first female mold part of the first slide mold and the first male mold part of the second slide mold. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2015-205395 A [Patent Document 2] JP 2004-276528 A Summary of the Invention [Problem to be solved by the invention]

[0007] In two-color molding, a two-sided mold is used, and the clamping force is distributed over a large area. If molding material is filled into both sides of the mold at the same time, the clamping force is insufficient and the mold unit may open. The problem of the mold unit opening due to the filling pressure of the molding material when clamping can occur in cases other than two-color molding.

[0008] One aspect of the present invention provides a technique for preventing a mold device from opening due to the filling pressure of a molding material when the mold is clamped. [Means for solving the problem]

[0009] A control device according to one aspect of the present invention is a control device for an injection molding machine that, when a mold device having a fixed mold and a movable mold is clamped, fills a molding material into each of a first cavity space and a second cavity space formed separately between the fixed mold and the movable mold. The control device provides an interval between a first peak timing at which a filling pressure for filling the first cavity space with the molding material reaches a maximum value and a second peak timing at which a filling pressure for filling the second cavity space with the molding material reaches a maximum value when the mold device is clamped. Effect of the Invention

[0010] According to one aspect of the present invention, it is possible to prevent the mold device from opening due to the filling pressure of the molding material when the mold is clamped. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a state when mold opening of an injection molding machine according to an embodiment is completed. [Diagram 2] FIG. 2 is a diagram showing a state during mold clamping of the injection molding machine according to one embodiment. [Diagram 3] FIG. 3 is a horizontal cross-sectional view showing a state of a mold device during mold clamping when the rotation angle of a turntable according to one embodiment is a first rotation angle. [Figure 4] FIG. 4 is a horizontal cross-sectional view showing a state of a mold device when the rotation angle of the turntable according to one embodiment is a first rotation angle and mold opening is completed. [Diagram 5] FIG. 5 is a horizontal cross-sectional view showing a state of a mold device during mold clamping when the rotation angle of the turntable according to one embodiment is the second rotation angle. [Figure 6] FIG. 6 is a horizontal cross-sectional view showing a state of the mold device when the rotation angle of the turntable according to one embodiment is the second rotation angle and mold opening is completed. [Figure 7] FIG. 7 is a vertical sectional view showing a state of a mold device during mold clamping when the rotation angle of the turntable according to one embodiment is a first rotation angle. [Figure 8] Figure 8(A) is a diagram showing a reference example of changes over time in the actual values ​​of the first filling pressure, the second filling pressure, and the clamping force, and Figure 8(B) is a diagram showing an example of changes over time in the actual values ​​of the first filling pressure, the second filling pressure, and the clamping force. [Figure 9] FIG. 9 is a diagram showing a die apparatus according to a first modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same reference numerals, and the description thereof may be omitted.

[0013] FIG. 1 is a diagram showing a state of an injection molding machine according to an embodiment when mold opening is completed. FIG. 2 is a diagram showing a state of an injection molding machine according to an embodiment when mold clamping is completed. FIG. 3 is a horizontal sectional view showing a state of a mold device at the time of mold clamping when the rotation angle of a turntable according to an embodiment is a first rotation angle. FIG. 4 is a horizontal sectional view showing a state of a mold device at the time of mold opening completion when the rotation angle of a turntable according to an embodiment is a first rotation angle. FIG. 5 is a horizontal sectional view showing a state of a mold device at the time of mold clamping when the rotation angle of a turntable according to an embodiment is a second rotation angle. FIG. 6 is a horizontal sectional view showing a state of a mold device at the time of mold opening completion when the rotation angle of a turntable according to an embodiment is a second rotation angle. FIG. 7 is a vertical sectional view showing a state of a mold device at the time of mold clamping when the rotation angle of a turntable according to an embodiment is a first rotation angle. Note that FIG. 1 and FIG. 2 are vertical sectional views taken along line II in FIG. 3.

[0014] In this specification, the X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other. The X-axis direction and the Y-axis direction represent the horizontal direction, and the Z-axis direction represents the vertical direction. When the mold clamping device 100 is of a horizontal type, the X-axis direction is the mold opening / closing direction, and the Y-axis direction is the width direction of the injection molding machine 10. The negative side of the Y-axis direction is called the operation side, and the positive side of the Y-axis direction is called the anti-operation side.

[0015] As shown in Figures 1 to 7, the injection molding machine 10 has a mold clamping device 100 that opens and closes the mold apparatus 800, a first ejector device 201 that ejects the first unwanted item 23 molded by the mold apparatus 800, a second ejector device 202 that ejects both the second molded item 22 and the second unwanted item 24 molded by the mold apparatus 800, a first injection device 301 that injects molding material into the mold apparatus 800, a second injection device 302 that injects molding material into the mold apparatus 800, a first moving device 401 that moves the first injection device 301 forward and backward relative to the mold apparatus 800, a second moving device (not shown) that moves the second injection device 302 forward and backward relative to the mold apparatus 800, a control device 700 that controls each component of the injection molding machine 10, and a frame 900 that supports each component of the injection molding machine 10. The frame 900 includes a mold clamping unit frame 910 and an injection unit frame 920. The mold clamping unit frame 910 and the injection unit frame 920 are each installed on the floor 2 via a leveling adjuster 930. The control device 700 is disposed in the internal space of the injection unit frame 920. Each component of the injection molding machine 10 will be described below.

[0016] (mold clamping device) In the description of the mold clamping unit 100, the moving direction of the movable platen 120 during mold closing (e.g., the positive direction of the X-axis) is defined as the front, and the moving direction of the movable platen 120 during mold opening (e.g., the negative direction of the X-axis) is defined as the rear. The mold clamping unit 100 performs mold closing, pressurization, mold clamping, depressurization, and mold opening of the mold device 800. The mold device 800 includes a fixed mold 810 and a movable mold 820.

[0017] As shown in Figs. 3 and 5, the fixed mold 810 has a first fixed molding surface 811 and a second fixed molding surface 812 on the surface facing the movable mold 820. The first fixed molding surface 811 forms a part of the wall surface of the first cavity space 801 in which the first molded product 21 is molded. On the other hand, the second fixed molding surface 812 forms a part of the wall surface of the second cavity space 802 in which the second molded product 22 is molded. The first fixed molding surface 811 and the second fixed molding surface 812 are formed in different shapes, for example, each of them is formed in a concave shape. In this embodiment, the first fixed molding surface 811 and the second fixed molding surface 812 are formed on the same fixed mold plate, but may be formed on different fixed mold plates as described in Patent Document 1.

[0018] The fixed mold 810 has multiple plates 813, 814, 815 that are stacked in the mold opening and closing direction. The plate 813 attached to the fixed platen 110 is called the fixed mounting plate 813. The plate 815 that forms the first cavity space 801 and the second cavity space 802 is called the fixed mold plate 815. The plate 814 disposed between the fixed mounting plate 813 and the fixed mold plate 815 is called the intermediate plate 814.

[0019] The movable mold 820 has a first movable molding surface 821 and a second movable molding surface 822 on the surface facing the fixed mold 810. The first movable molding surface 821 and the second movable molding surface 822 form a part of the wall surface of the first cavity space 801 and a part of the wall surface of the second cavity space 802, respectively, as shown in Figs. 3 and 5. The first movable molding surface 821 and the second movable molding surface 822 are formed in the same shape, for example, in a convex shape. The first movable molding surface 821 and the second movable molding surface 822 are formed on the same movable mold plate in this embodiment, but may be formed on different movable mold plates as described in Patent Document 1.

[0020] The movable mold 820 has multiple plates 823, 824, 825 that are stacked in the mold opening and closing direction. The plate 823 that is attached to the movable platen 120 via the rotating plate 520 is called the movable mounting plate 823. The plate 825 that forms the first cavity space 801 and the second cavity space 802 is called the movable mold plate 825. The plate 824 that is disposed between the movable mounting plate 823 and the movable mold plate 825 is called the spacer block 824. The spacer block 824 forms a space between the movable mounting plate 823 and the movable mold plate 825.

[0021] 4 and 6, the movable mold 820 has a fixed part 830 fixed to the movable platen 120, a first movable part 840 that protrudes both the first unnecessary part 23 and the second unnecessary part 24 from the fixed part 830, and a second movable part 850 that protrudes the second molded product 22 from the fixed part 830. A plurality of sets of the first movable part 840 and the second movable part 850 are provided.

[0022] The fixed portion 830 includes a movable mounting plate 823, a spacer block 824, and a movable mold plate 825. The movable mounting plate 823 is formed with a through hole 823a into which the first ejector rod 211 and the second ejector rod 212 are inserted and removed in sequence. The diameter of the through hole 823a is larger than the diameter of the first ejector rod 211 and the diameter of the second ejector rod 212.

[0023] The first movable portion 840 includes, for example, a first ejector plate 841 that is disposed perpendicular to the mold opening / closing direction, and a rod-shaped first ejector pin 842 that extends forward from the first ejector plate 841.

[0024] The first ejector plate 841 is disposed in the space between the movable mounting plate 823 and the movable mold plate 825. The first ejector plate 841 advances and retreats along guide pins 829 parallel to the mold opening and closing direction. The first ejector plate 841 is biased by a first return spring 843 in a direction away from the movable mold plate 825.

[0025] The first ejector pin 842 is arranged so as to be able to move forward and backward in a first pin hole that penetrates the movable mold plate 825 in the mold opening and closing direction. The front end surface of the first ejector pin 842 abuts against the first unnecessary part 23 or the second unnecessary part 24.

[0026] The second movable portion 850 includes, for example, a second ejector plate 851 that is disposed perpendicular to the mold opening / closing direction, and a rod-shaped second ejector pin 852 that extends forward from the second ejector plate 851.

[0027] The second ejector plate 851 is disposed in the space between the movable mounting plate 823 and the movable mold plate 825. The second ejector plate 851 advances and retreats along guide pins 829 parallel to the mold opening and closing direction. The second ejector plate 851 is biased by a second return spring 853 in a direction away from the movable mold plate 825.

[0028] The second ejector plate 851 is disposed between the movable mounting plate 823 and the first ejector plate 841. When the second ejector plate 851 advances or retreats, the first ejector plate 841 advances or retreats together with the second ejector plate 851.

[0029] A through hole 851a is formed in the second ejector plate 851, penetrating the second ejector plate 851 in the mold opening / closing direction. The diameter of the through hole 851a is larger than the diameter of the first ejector rod 211 and smaller than the diameter of the second ejector rod 212. The first ejector rod 211 passes through the through hole 851a, but the second ejector rod 212 does not pass through the through hole 851a.

[0030] The second ejector pin 852 is arranged so as to be able to move forward and backward in a second pin hole that penetrates the movable mold plate 825 in the mold opening and closing direction. A front end surface of the second ejector pin 852 abuts against the first molded product 21 or the second molded product 22.

[0031] In this embodiment, the first fixed molding surface 811 and the second fixed molding surface 812 are formed in a concave shape, and the first movable molding surface 821 and the second movable molding surface 822 are formed in a convex shape, but the present invention is not limited to this. In other words, the first fixed molding surface 811 and the second fixed molding surface 812 may be formed in a convex shape, and the first movable molding surface 821 and the second movable molding surface 822 may be formed in a concave shape.

[0032] 1 and 2, the mold clamping apparatus 100 is, for example, a horizontal type, and the mold opening and closing direction is horizontal. The mold clamping apparatus 100 has a fixed platen 110 to which a fixed mold 810 is attached, a rotating platen 520 to which a movable mold 820 is attached, a movable platen 120 to which the rotating platen 520 is rotatably attached, a rotating mechanism 530 that rotates the rotating platen 520, and a moving mechanism 102 that moves the movable platen 120 in the mold opening and closing direction relative to the fixed platen 110.

[0033] The stationary platen 110 is fixed to the mold clamping unit frame 910. On the surface of the stationary platen 110 facing the movable platen 120, a stationary mold 810 is attached.

[0034] The movable platen 120 is disposed so as to be movable in the mold opening and closing direction relative to the mold clamping unit frame 910. A guide 101 for guiding the movable platen 120 is laid on the mold clamping unit frame 910. A rotating platen 520 is attached to the surface of the movable platen 120 facing the fixed platen 110. As shown in FIGS. 3 to 7, the movable platen 120 rotatably supports a rotating shaft 571 of the rotating platen 520 via a bearing 572.

[0035] The rotating platen 520 is rotatably attached to the movable platen 120. A rotation center line 520X of the rotating platen 520 is parallel to the mold opening / closing direction. The rotating platen 520 includes, for example, a mold mounting portion 521, a disk portion 523 that supports the mold mounting portion 521 from the rear, and a cylindrical portion 524 that extends rearward from the outer periphery of the disk portion 523, as shown in Fig. 7. A movable mold 820 is attached to the surface of the mold mounting portion 521 that faces the fixed platen 110.

[0036] Rotation mechanism 530 (see FIG. 7) rotates rotating plate 520. Rotation mechanism 530 has a rotation motor 531 and a transmission mechanism 532 that transmits the rotational driving force of rotation motor 531 to rotating plate 520. Transmission mechanism 532 is composed of, for example, a drive gear 533, an intermediate gear 534, and a driven gear 535. The intermediate gear 534 may not be provided, and the drive gear 533 and the driven gear 535 may be coupled to each other.

[0037] The rotation mechanism 530 rotates the rotating platen 520 to a first rotation angle and a second rotation angle. The first rotation angle is a rotation angle at which the first fixed molding surface 811 and the first movable molding surface 821 form a first cavity space 801, and the second fixed molding surface 812 and the second movable molding surface 822 form a second cavity space 802, as shown in FIG. 3, for example. The first rotation angle is 0°, for example. On the other hand, the second rotation angle is a rotation angle at which the first fixed molding surface 811 and the second movable molding surface 822 form a first cavity space 801, and the second fixed molding surface 812 and the first movable molding surface 821 form a second cavity space 802, as shown in FIG. 5. The second rotation angle is 180°, for example.

[0038] The rotation direction of the turntable 520 may be reversed every time the turntable 520 is rotated 180°. For example, the rotation mechanism 530 rotates the turntable 520 180° clockwise, and then rotates the turntable 520 180° counterclockwise. Since the arrangement of the wiring and piping fixed to the turntable 520 is restored to the original state, the wiring and piping can be easily arranged.

[0039] 3, when the rotation angle of the turntable 520 is a first rotation angle, clamping is performed, whereby the first fixed molding surface 811 and the first movable molding surface 821 form a first cavity space 801, and the second fixed molding surface 812 and the second movable molding surface 822 form a second cavity space 802. Molding material is supplied from the first injection device 301 to the first cavity space 801, and the first molded product 21 is molded. Then, the mold is opened.

[0040] Next, as shown in FIG. 4, the first ejector device 201 ejects the first unnecessary part 23 from the movable mold 820. The first unnecessary part 23 has solidified inside the mold device 800 together with the first molded product 21. At this time, the first molded product 21 is not ejected from the movable mold 820. Next, the rotation mechanism 530 rotates the turntable 520 by 180°. At this time, the first molded product 21 is rotated by 180° together with the movable mold 820. Thereafter, the mold is clamped as shown in FIG.

[0041] As shown in FIG. 5, when the rotation angle of the rotating platen 520 is the second rotation angle, the first fixed molding surface 811 and the second movable molding surface 822 form the first cavity space 801, and the second fixed molding surface 812 and the first movable molding surface 821 form the second cavity space 802. The first molded product 21 is disposed in a part of the second cavity space 802. The molding material is supplied from the second injection device 302 to the remaining part of the second cavity space 802, and the second molded product 22 is molded. The second molded product 22 will be described as including the first molded product 21. The first molded product 21 is molded in parallel with the molding of the second molded product 22. The first molded product 21 is molded in the first cavity space 801. Then, the mold is opened.

[0042] 6, the second ejector device 202 ejects both the second molded product 22 and the second unnecessary product 24 from the movable mold 820. The second unnecessary product 24 is solidified inside the mold device 800 together with the second molded product 22. After being ejected from the movable mold 820, the second unnecessary product 24 is separated from the second molded product 22. In parallel with the ejection of both the second molded product 22 and the second unnecessary product 24, the first unnecessary product 23 is ejected. Thereafter, the mold is opened, and the turntable 520 is rotated 180° again.

[0043] 3 and 5, the movable platen 120 has a front plate 121 that rotatably supports the rotating platen 520, an intermediate block 124 that is disposed radially inside the cylindrical portion 524 of the rotating platen 520, a rear block 126 that is provided rearward of the intermediate block 124, and a toggle link attachment portion 128 (see FIG. 7) that is provided on the rear end surface of the rear block 126. The front plate 121, the intermediate block 124, the rear block 126, and the toggle link attachment portion 128 may be formed separately and connected together, or may be formed integrally by casting or the like.

[0044] The front plate 121 supports the rotating plate 520 so as to be freely rotatable. A first rod hole 122 penetrating the front plate 121 in the mold opening / closing direction is formed in the front plate 121. A first ejector rod 211 is arranged in the first rod hole 122 so as to be able to move forward and backward. Furthermore, a second rod hole 123 penetrating the front plate 121 in the mold opening / closing direction is formed in the front plate 121. A second ejector rod 212 is arranged in the second rod hole 123 so as to be able to move forward and backward.

[0045] The intermediate block 124 is disposed radially inside the cylindrical portion 524 of the rotating platen 520. The intermediate block 124 has, for example, a cylindrical shape that fits inside the cylindrical portion 524 of the rotating platen 520 when viewed in the mold opening / closing direction. Inside the intermediate block 124, a space in which the first ejector device 201 is disposed and a space in which the second ejector device 202 is disposed are formed. A front plate 121 is attached to the front end surface of the intermediate block 124. An insertion hole 127 into which a rotating shaft 571 of the rotating platen 520 is inserted via a bearing 572 is formed in the front plate 121 and the intermediate block 124.

[0046] The rear block 126 is provided behind the intermediate block 124. The rear block 126 has, for example, a rectangular shape. Inside the rear block 126, a space in which the first ejector device 201 is disposed and a space in which the second ejector device 202 is disposed are formed. The intermediate block 124 is attached to a front end surface of the rear block 126.

[0047] A pair of toggle link mounting portions 128 (see FIG. 7) are provided on the rear end surface of the rear block 126 with a vertical gap between them. Each of the pair of toggle link mounting portions 128 has a plurality of toggle link mounting plates with their plate thickness directions facing horizontally and spaced apart in the horizontal direction. Each of the plurality of toggle link mounting plates protrudes rearward from the rear end surface of the rear block 126 and has a pin hole 129 at its tip. A pin is inserted into the pin hole 129, and a first link 152 (see FIG. 1 and FIG. 2) is attached to the toggle link mounting portion 128 via the pin in a manner that allows it to freely swing.

[0048] The moving mechanism 102 (see FIGS. 1 and 2) advances and retreats the movable platen 120 relative to the fixed platen 110, thereby performing mold closing, pressurization, mold clamping, depressurization, and mold opening of the mold device 800. The moving mechanism 102 has a toggle support 130 arranged at a distance from the fixed platen 110, a tie bar 140 connecting the fixed platen 110 and the toggle support 130, a toggle mechanism 150 that moves the movable platen 120 in the mold opening and closing direction relative to the toggle support 130, a mold clamping motor 160 that operates the toggle mechanism 150, a motion conversion mechanism 170 that converts the rotational motion of the mold clamping motor 160 into linear motion, and a mold thickness adjustment mechanism 180 that adjusts the distance between the fixed platen 110 and the toggle support 130.

[0049] The toggle support 130 is disposed at a distance from the fixed platen 110, and is placed on the mold clamping unit frame 910 so as to be freely movable in the mold opening and closing direction. The toggle support 130 may be disposed so as to be freely movable along a guide laid on the mold clamping unit frame 910. The guide of the toggle support 130 may be the same as the guide 101 of the movable platen 120.

[0050] In this embodiment, the fixed platen 110 is fixed to the mold clamping unit frame 910, and the toggle support 130 is arranged so as to be freely movable in the mold opening and closing direction relative to the mold clamping unit frame 910, but the toggle support 130 may be fixed to the mold clamping unit frame 910, and the fixed platen 110 may be arranged so as to be freely movable in the mold opening and closing direction relative to the mold clamping unit frame 910.

[0051] The tie bar 140 connects the fixed platen 110 and the toggle support 130 at a distance L in the mold opening / closing direction. A plurality of tie bars 140 (for example, four) may be used. The plurality of tie bars 140 are arranged parallel to the mold opening / closing direction and extend according to the mold clamping force. At least one tie bar 140 may be provided with a tie bar strain detector 141 that detects strain of the tie bar 140. The tie bar strain detector 141 sends a signal indicating the detection result to the control device 700. The detection result of the tie bar strain detector 141 is used for detecting the mold clamping force, etc.

[0052] In this embodiment, the tie bar strain detector 141 is used as a clamping force detector for detecting the clamping force, but the present invention is not limited to this. The clamping force detector is not limited to the strain gauge type, and may be a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and the attachment position is not limited to the tie bar 140.

[0053] The toggle mechanism 150 is disposed between the movable platen 120 and the toggle support 130, and moves the movable platen 120 relative to the toggle support 130 in the mold opening / closing direction. The toggle mechanism 150 has a crosshead 151 that moves in the mold opening / closing direction, and a pair of link groups that bend and stretch with the movement of the crosshead 151. Each of the pair of link groups has a first link 152 and a second link 153 that are connected to bendable and stretchable by a pin or the like. The first link 152 is attached to the movable platen 120 by a pin or the like so as to be swingable. The second link 153 is attached to the toggle support 130 by a pin or the like so as to be swingable. The second link 153 is attached to the crosshead 151 via a third link 154. When the crosshead 151 is advanced or retreated relative to the toggle support 130, the first link 152 and the second link 153 bend and stretch, and the movable platen 120 advances or retreats relative to the toggle support 130.

[0054] The configuration of the toggle mechanism 150 is not limited to the configuration shown in Figures 1 and 2. For example, although the number of joints in each link group is five in Figures 1 and 2, it may be four, and one end of the third link 154 may be connected to a joint between the first link 152 and the second link 153.

[0055] The mold clamping motor 160 is attached to the toggle support 130 and operates the toggle mechanism 150. The mold clamping motor 160 advances and retreats the crosshead 151 relative to the toggle support 130, thereby bending and extending the first link 152 and the second link 153 and advancing and retreating the movable platen 120 relative to the toggle support 130. The mold clamping motor 160 is directly connected to the motion conversion mechanism 170, but may also be connected to the motion conversion mechanism 170 via a belt, a pulley, or the like.

[0056] The motion conversion mechanism 170 converts the rotational motion of the mold clamping motor 160 into the linear motion of the crosshead 151. The motion conversion mechanism 170 includes a screw shaft and a screw nut that screws onto the screw shaft. A ball or roller may be interposed between the screw shaft and the screw nut.

[0057] The mold clamping device 100 performs a mold closing process, a pressure increase process, a mold clamping process, a pressure release process, a mold opening process, a mold rotation process, and the like under the control of the control device 700. The mold rotation process is performed after the mold opening process is completed and before the start of the next mold closing process. In this embodiment, the mold rotation process is performed after the ejection process is completed, but it may be performed before the ejection process is completed. For example, when the position where the second molded product 22 is molded is different from the position where the second molded product 22 is ejected, the mold rotation process is performed after the mold opening process is completed, and then the ejection process is performed. Specifically, for example, when the position where the second molded product 22 is molded is the operation side and the position where the second molded product 22 is ejected is the anti-operation side, the mold rotation process is performed after the mold opening process is completed, and then the ejection process is performed.

[0058] In the mold closing process, the mold clamping motor 160 is driven to move the crosshead 151 forward at a set moving speed to a mold closing completion position, thereby moving the movable platen 120 forward and bringing the movable mold 820 into contact with the fixed mold 810. The position and moving speed of the crosshead 151 are detected by using, for example, a mold clamping motor encoder 161. The mold clamping motor encoder 161 detects the rotation of the mold clamping motor 160 and sends a signal indicating the detection result to the control device 700.

[0059] The crosshead position detector that detects the position of the crosshead 151 and the crosshead movement speed detector that detects the movement speed of the crosshead 151 are not limited to the mold clamping motor encoder 161, and general devices can be used. Furthermore, the movable platen position detector that detects the position of the movable platen 120 and the movable platen movement speed detector that detects the movement speed of the movable platen 120 are not limited to the mold clamping motor encoder 161, and general devices can be used.

[0060] In the pressure increasing step, the mold clamping motor 160 is further driven to move the crosshead 151 further forward from the mold closing completion position to the mold clamping position, thereby generating a mold clamping force.

[0061] In the mold clamping process, the mold clamping motor 160 is driven to maintain the position of the crosshead 151 at the mold clamping position. In the mold clamping process, the mold clamping force generated in the pressure increase process is maintained. In the mold clamping process, a first cavity space 801 and a second cavity space 802 are formed in the mold device 800.

[0062] In the depressurization process, the mold clamping motor 160 is driven to move the crosshead 151 back from the mold clamping position to the mold opening start position, thereby moving the movable platen 120 back and reducing the mold clamping force. The mold opening start position and the mold closing completion position may be the same position.

[0063] In the mold opening process, the mold clamping motor 160 is driven to move the crosshead 151 backward at a set moving speed from the mold opening start position to the mold opening completion position, thereby moving the movable platen 120 backward and separating the movable mold 820 from the fixed mold 810.

[0064] After the mold opening process is completed, and before the start of the next mold closing process, an ejection process is performed. In the ejection process, the first ejector device 201 ejects the first unnecessary part 23 from the movable mold 820. The first molded product 21 that has solidified together with the first unnecessary part 23 is not ejected. In the ejection process, the second ejector device 202 ejects both the second molded product 22 and the second unnecessary part 24 from the movable mold 820. After the ejection process is completed, and before the start of the next mold closing process, a mold rotation process is performed.

[0065] In the mold rotation step, the turntable 520 rotates, and rotates the first molded product 21 together with the movable mold 820. Thereafter, the mold closing step and the pressure increasing step are performed, whereby the first molded product 21 is disposed in a part of the second cavity space 802.

[0066] The setting conditions in the mold closing process, the pressure increase process, and the mold clamping process are set together as a series of setting conditions. For example, the moving speed and position of the crosshead 151 in the mold closing process and the pressure increase process (including the mold closing start position, the moving speed switching position, the mold closing completion position, and the mold clamping position) and the mold clamping force are set together as a series of setting conditions. The mold closing start position, the moving speed switching position, the mold closing completion position, and the mold clamping position are arranged in this order from the rear side to the front, and represent the start point and the end point of the section in which the moving speed is set. The moving speed is set for each section. There may be one or more moving speed switching positions. The moving speed switching position does not have to be set. Only one of the mold clamping position and the mold clamping force may be set.

[0067] The setting conditions in the depressurization process and mold opening process are set in the same manner. For example, the movement speed and position of the crosshead 151 in the depressurization process and mold opening process (mold opening start position, movement speed switching position, and mold opening completion position) are set together as a series of setting conditions. The mold opening start position, movement speed switching position, and mold opening completion position are arranged in this order from the front to the rear, and represent the start and end points of the section in which the movement speed is set. The movement speed is set for each section. There may be one or more movement speed switching positions. The movement speed switching position does not have to be set. The mold opening start position and the mold closing completion position may be the same position. Also, the mold opening completion position and the mold closing start position may be the same position.

[0068] It should be noted that the moving speed and position of the movable platen 120 may be set instead of the moving speed and position of the crosshead 151. Moreover, the clamping force may be set instead of the position of the crosshead (e.g., the clamping position) or the position of the movable platen.

[0069] Incidentally, the toggle mechanism 150 amplifies the driving force of the mold clamping motor 160 and transmits it to the movable platen 120. The amplification ratio is also called the toggle ratio. The toggle ratio changes according to the angle θ between the first link 152 and the second link 153 (hereinafter also referred to as the "link angle θ"). The link angle θ is determined from the position of the crosshead 151. When the link angle θ is 180°, the toggle ratio is maximum.

[0070] When the thickness of the mold device 800 changes due to replacement of the mold device 800 or a temperature change of the mold device 800, a mold thickness adjustment is performed so that a predetermined clamping force is obtained during mold clamping. In the mold thickness adjustment, for example, the distance L between the fixed platen 110 and the toggle support 130 is adjusted so that the link angle θ of the toggle mechanism 150 becomes a predetermined angle at the mold touch time when the movable mold 820 touches the fixed mold 810.

[0071] The mold clamping device 100 has a mold thickness adjustment mechanism 180. The mold thickness adjustment mechanism 180 adjusts the mold thickness by adjusting the distance L between the fixed platen 110 and the toggle support 130. The mold thickness adjustment is performed, for example, between the end of a molding cycle and the start of the next molding cycle. The mold thickness adjustment mechanism 180 has, for example, a screw shaft 181 formed at the rear end of the tie bar 140, a screw nut 182 held rotatably and immovably on the toggle support 130, and a mold thickness adjustment motor 183 that rotates the screw nut 182 screwed onto the screw shaft 181.

[0072] The screw shaft 181 and the screw nut 182 are provided for each tie bar 140. The rotational driving force of the mold thickness adjustment motor 183 may be transmitted to the multiple screw nuts 182 via a rotational driving force transmission unit 185. The multiple screw nuts 182 can be rotated synchronously. Note that by changing the transmission path of the rotational driving force transmission unit 185, it is also possible to rotate the multiple screw nuts 182 individually.

[0073] The rotational drive force transmission unit 185 is composed of, for example, gears. In this case, a driven gear is formed on the outer periphery of each screw nut 182, a drive gear is attached to the output shaft of the mold thickness adjustment motor 183, and an intermediate gear that meshes with the multiple driven gears and the drive gear is rotatably held in the center of the toggle support 130. Note that the rotational drive force transmission unit 185 may be composed of a belt, a pulley, or the like, instead of gears.

[0074] The operation of the mold thickness adjustment mechanism 180 is controlled by a control device 700. The control device 700 drives the mold thickness adjustment motor 183 to rotate the screw nut 182. As a result, the position of the toggle support 130 relative to the tie bar 140 is adjusted, and the interval L between the fixed platen 110 and the toggle support 130 is adjusted. Note that a plurality of mold thickness adjustment mechanisms may be used in combination.

[0075] The distance L is detected using a mold thickness adjustment motor encoder 184. The mold thickness adjustment motor encoder 184 detects the amount of rotation and the direction of rotation of the mold thickness adjustment motor 183, and sends a signal indicating the detection result to the control device 700. The detection result of the mold thickness adjustment motor encoder 184 is used to monitor and control the position of the toggle support 130 and the distance L. Note that the toggle support position detector that detects the position of the toggle support 130 and the distance detector that detects the distance L are not limited to the mold thickness adjustment motor encoder 184, and general detectors can be used.

[0076] The mold clamping apparatus 100 may have a mold temperature regulator that regulates the temperature of the mold apparatus 800. The mold apparatus 800 has a flow path for a temperature control medium therein. The mold temperature regulator regulates the temperature of the mold apparatus 800 by regulating the temperature of the temperature control medium supplied to the flow path of the mold apparatus 800.

[0077] Incidentally, the mold clamping unit 100 of this embodiment is of a horizontal type in which the mold opening and closing direction is horizontal, but it may be of a vertical type in which the mold opening and closing direction is vertical.

[0078] Although the mold clamping apparatus 100 of the present embodiment has a mold clamping motor 160 as a drive unit, it may have a hydraulic cylinder instead of the mold clamping motor 160. Also, the mold clamping apparatus 100 may have a linear motor for opening and closing the mold, and an electromagnet for mold clamping.

[0079] (First ejector device and second ejector device) In describing the first ejector device 201 and the second ejector device 202, similar to the description of the mold clamping device 100, the movement direction of the movable platen 120 when the mold is closed (e.g., the positive direction of the X-axis) is defined as the front, and the movement direction of the movable platen 120 when the mold is opened (e.g., the negative direction of the X-axis) is defined as the rear.

[0080] The first ejector device 201 and the second ejector device 202 are attached to the movable platen 120 and move forward and backward together with the movable platen 120. The first ejector device 201 ejects the first unwanted product 23 from the movable mold 820. At this time, the first ejector device 201 does not eject the solidified first molded product 21 together with the first unwanted product 23. The second ejector device 202 ejects both the second molded product 22 and the second unwanted product 24 from the movable mold 820.

[0081] The first ejector device 201 and the second ejector device 202 are disposed at an interval in the Y-axis direction. This is because the first cavity space 801 and the second cavity space 802 are disposed at an interval in the Y-axis direction. For example, the first cavity space 801 and the first ejector device 201 are disposed on the operation side. Furthermore, the second cavity space 802 and the second ejector device 202 are disposed on the anti-operation side. This allows the second molded product 22 to be taken out to the anti-operation side.

[0082] Next, the first ejector device 201 and its operation will be described mainly with reference to Fig. 4. The first ejector device 201 has a first ejector rod 211 that presses only the first movable part 840 out of the first movable part 840 and the second movable part 850. The first ejector rod 211 is not connected to the first movable part 840. The first ejector rod 211 can be removed from the rotating plate 520, allowing the rotating plate 520 to rotate.

[0083] The first ejector device 201 has a first drive mechanism 220 that advances and retreats the first ejector rod 211. The first drive mechanism 220 has, for example, a first ejector motor 221, a first crosshead 223, and a first motion conversion mechanism 225 that converts the rotational motion of the first ejector motor 221 into the linear motion of the first crosshead 223.

[0084] The first motion conversion mechanism 225 includes a screw shaft and a screw nut screwed onto the screw shaft. A ball or roller may be interposed between the screw shaft and the screw nut. The first crosshead 223 moves in the mold opening / closing direction along the first guide bar 224. The rear end of the first ejector rod 211 is attached to the first crosshead 223, and the first ejector rod 211 advances and retreats together with the first crosshead 223.

[0085] 4, when the first drive mechanism 220 moves the first ejector rod 211 forward, the first ejector rod 211 passes through the through hole 823a of the movable mounting plate 823 and the through hole 851a of the second ejector plate 851, and pushes the first ejector plate 841 forward. As a result, the first ejector plate 841 moves forward against the biasing force of the first return spring 843. Therefore, the first ejector pin 842 moves forward, and ejects the first unnecessary part 23 from the fixed part 830.

[0086] 4, while the first drive mechanism 220 advances the first ejector plate 841 together with the first ejector rod 211, the second ejector plate 851 is held at the most retracted position by the urging force of the second return spring 853 and does not advance. Therefore, when the first unnecessary product 23 is ejected from the fixed portion 830, the first molded product 21 is not ejected from the fixed portion 830.

[0087] Thereafter, when the first drive mechanism 220 retracts the first ejector rod 211, the first ejector plate 841 is retracted to a retract limit position by the biasing force of the first return spring 843. When the first ejector plate 841 reaches the retract limit position, the front end surface of the first ejector pin 842 becomes flush with the front end surface of the fixed portion 830.

[0088] The control device 700 controls the position of the first ejector rod 211 when the first ejector rod 211 advances and retreats. The position of the first ejector rod 211 is detected by using, for example, a first ejector motor encoder 222. The first ejector motor encoder 222 detects the rotation of the first ejector motor 221 and sends a signal indicating the detection result to the control device 700. Note that the first ejector rod position detector that detects the position of the first ejector rod 211 is not limited to the first ejector motor encoder 222, and a general one can be used.

[0089] Next, the second ejector device 202 and its operation will be described mainly with reference to Fig. 6. The second ejector device 202 has a second ejector rod 212 that presses a first movable part 840 and a second movable part 850. The second ejector rod 212 is not connected to the first movable part 840 and the second movable part 850. The second ejector rod 212 can be removed from the rotating platen 520, and the rotating platen 520 can be rotated.

[0090] The second ejector device 202 has a second drive mechanism 230 that advances and retreats the second ejector rod 212. The second drive mechanism 230 has, for example, a second ejector motor 231, a second crosshead 233, and a second motion conversion mechanism 235 that converts the rotational motion of the second ejector motor 231 into the linear motion of the second crosshead 233.

[0091] The second motion conversion mechanism 235 includes a screw shaft and a screw nut screwed onto the screw shaft. A ball or roller may be interposed between the screw shaft and the screw nut. The second crosshead 233 moves in the mold opening / closing direction along the second guide bar 234. The rear end of the second ejector rod 212 is attached to the second crosshead 233, and the second ejector rod 212 advances and retreats together with the second crosshead 233.

[0092] 6, when the second drive mechanism 230 advances the second ejector rod 212, the second ejector rod 212 passes through the through hole 823a of the movable mounting plate 823 and pushes forward the edge of the through hole 851a of the second ejector plate 851. As a result, the second ejector plate 851 advances against the biasing force of the second return spring 853. Therefore, the second ejector pin 852 advances and ejects the second molded product 22 from the fixed part 830.

[0093] While the second drive mechanism 230 advances the second ejector plate 851 together with the second ejector rod 212, the first ejector plate 841 advances against the biasing force of the first return spring 843. Therefore, the first ejector pin 842 advances and ejects the second waste product 24 from the fixed portion 830.

[0094] Thereafter, when the second drive mechanism 230 retracts the second ejector rod 212, the second ejector plate 851 is retracted to a retract limit position by the biasing force of the second return spring 853. When the second ejector plate 851 reaches the retract limit position, the front end surface of the second ejector pin 852 becomes flush with the front end surface of the fixed portion 830.

[0095] While the second ejector plate 851 is retracting, the first ejector plate 841 is retracted to a rearmost position by the biasing force of the first return spring 843. When the first ejector plate 841 reaches the rearmost position, the front end surface of the first ejector pin 842 becomes flush with the front end surface of the fixed portion 830.

[0096] The control device 700 controls the position of the second ejector rod 212 when the second ejector rod 212 advances and retreats. The position of the second ejector rod 212 is detected by using, for example, the second ejector motor encoder 232. The second ejector motor encoder 232 detects the rotation of the second ejector motor 231 and sends a signal indicating the detection result to the control device 700. Note that the second ejector rod position detector that detects the position of the second ejector rod 212 is not limited to the second ejector motor encoder 232, and a general one can be used.

[0097] (First injection device and second injection device) In the description of the first injection unit 301 and the second injection unit 302, unlike the description of the mold clamping unit 100, etc., the movement direction of the screw 330 during filling (e.g., the negative direction of the X-axis) is described as the forward direction, and the movement direction of the screw 330 during metering (e.g., the positive direction of the X-axis) is described as the rearward direction.

[0098] The first injection unit 301 is mounted on a first slide base 303, and the first slide base 303 is disposed so as to be movable forward and backward with respect to the injection unit frame 920. The first injection unit 301 is disposed so as to be movable forward and backward with respect to the mold unit 800. The first injection unit 301 touches the mold unit 800 and injects molding material into the mold unit 800, thereby filling the first cavity space 801 with the molding material.

[0099] The second injection device 302 is installed on a second slide base, and the second slide base is disposed so as to be freely movable forward and backward with respect to the injection device frame 920. The second injection device 302 is disposed so as to be freely movable forward and backward with respect to the mold device 800. The second injection device 302 touches the mold device 800 and injects molding material into the interior of the mold device 800, thereby filling the second cavity space 802 with the molding material.

[0100] The first injection device 301 and the second injection device 302 are disposed at an interval in the Y-axis direction. This is because the first cavity space 801 and the second cavity space 802 are disposed at an interval in the Y-axis direction. The molding material that the first injection device 301 fills into the first cavity space 801 and the molding material that the second injection device 302 fills into the second cavity space 802 may be different materials or the same material.

[0101] The first injection unit 301 and the second injection unit 302 have the same configuration. Therefore, hereinafter, the configuration of the first injection unit 301 will be described, and a description of the configuration of the second injection unit 302 will be omitted.

[0102] As shown in Figures 1 and 2, the first injection device 301 has, for example, a cylinder 310 that heats the molding material, a nozzle 320 provided at the front end of the cylinder 310, a screw 330 that is arranged within the cylinder 310 so as to be rotatable and move back and forth, a metering motor 340 that rotates the screw 330, an injection motor 350 that moves the screw 330 back and forth, and a load detector 360 that detects the load transmitted between the injection motor 350 and the screw 330.

[0103] Cylinder 310 heats the molding material supplied to the inside from supply port 311. The molding material includes, for example, resin. The molding material is formed, for example, in the shape of pellets, and is supplied to supply port 311 in a solid state. Supply port 311 is formed at the rear of cylinder 310. A cooler 312 such as a water-cooled cylinder is provided on the outer periphery of the rear of cylinder 310. A heater 313 such as a band heater and a temperature detector 314 are provided on the outer periphery of cylinder 310, forward of cooler 312.

[0104] Cylinder 310 is divided into a plurality of zones in the axial direction (e.g., X-axis direction) of cylinder 310. Each of the plurality of zones is provided with heater 313 and temperature detector 314. A set temperature is set for each of the plurality of zones, and control device 700 controls heater 313 so that the detected temperature of temperature detector 314 becomes the set temperature.

[0105] The nozzle 320 is provided at the front end of the cylinder 310, and is pressed against the mold 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.

[0106] The screw 330 is disposed in the cylinder 310 so as to be rotatable and movable forward and backward. When the screw 330 is rotated, the molding material is sent forward along the spiral groove of the screw 330. As the molding material is sent forward, it is gradually melted by heat from the cylinder 310. As the liquid molding material is sent forward of the screw 330 and accumulates in the front part of the cylinder 310, the screw 330 is moved backward. Thereafter, when the screw 330 is moved forward, the liquid molding material accumulated in front of the screw 330 is injected from the nozzle 320 and filled into the mold device 800.

[0107] A check ring 331 is attached to the front of the screw 330 so as to be movable back and forth as a check valve for preventing the backflow of molding material from the front to the rear of the screw 330 when the screw 330 is pushed forward.

[0108] When the screw 330 is moved forward, the backflow prevention ring 331 is pushed backward by the pressure of the molding material in front of the screw 330, and moves backward relatively to the screw 330 to a blocking position (see FIG. 2) where the flow path of the molding material is blocked. This prevents the molding material accumulated in front of the screw 330 from flowing backward.

[0109] On the other hand, when the screw 330 is rotated, the backflow prevention ring 331 is pushed forward by the pressure of the molding material sent forward along the spiral groove of the screw 330, and moves forward relatively to the screw 330 to an open position (see FIG. 1) where the flow path of the molding material is opened. As a result, the molding material is sent forward of the screw 330.

[0110] The backflow prevention ring 331 may be either a co-rotating type that rotates together with the screw 330 or a non-co-rotating type that does not rotate together with the screw 330.

[0111] The first injection device 301 may have a drive source for moving the backflow prevention ring 331 back and forth between the open position and the closed position relative to the screw 330.

[0112] The metering motor 340 rotates the screw 330. The drive source for rotating the screw 330 is not limited to the metering motor 340, and may be, for example, a hydraulic pump.

[0113] The injection motor 350 advances and retreats the screw 330. A motion conversion mechanism that converts the rotational motion of the injection motor 350 into the linear motion of the screw 330 is provided between the injection motor 350 and the screw 330. The motion conversion mechanism has, for example, a screw shaft and a screw nut that screws onto the screw shaft. A ball or roller may be provided between the screw shaft and the screw nut. The drive source that advances and retreats the screw 330 is not limited to the injection motor 350, and may be, for example, a hydraulic cylinder.

[0114] The load detector 360 detects the load transmitted between the injection motor 350 and the screw 330. The detected load is converted into pressure by the control device 700. The load detector 360 is provided on a load transmission path between the injection motor 350 and the screw 330, and detects the load acting on the load detector 360.

[0115] The load detector 360 sends a signal of the detected load to the control device 700. The load detected by the load detector 360 is converted into pressure acting between the screw 330 and the molding material, and is used to control and monitor the pressure that the screw 330 receives from the molding material, the back pressure on the screw 330, the pressure that the screw 330 acts on the molding material, and the like.

[0116] The pressure detector for detecting the pressure of the molding material is not limited to the load detector 360, and a general detector may be used. For example, a nozzle pressure sensor or a mold internal pressure sensor may be used. The nozzle pressure sensor is installed in the nozzle 320. The mold internal pressure sensor is installed inside the mold device 800.

[0117] The first injection device 301 performs a metering process, a filling process, a pressure holding process, and the like under the control of the control device 700. The filling process and the pressure holding process may be collectively referred to as the injection process.

[0118] In the metering process, the metering motor 340 is driven to rotate the screw 330 at a set rotation speed, and the molding material is sent forward along the spiral groove of the screw 330. As a result, the molding material is gradually melted. As the liquid molding material is sent forward of the screw 330 and accumulates at the front of the cylinder 310, the screw 330 is moved backward. The rotation speed of the screw 330 is detected, for example, by using a metering motor encoder 341. The metering motor encoder 341 detects the rotation of the metering motor 340 and sends a signal indicating the detection result to the control device 700. Note that the screw rotation speed detector that detects the rotation speed of the screw 330 is not limited to the metering motor encoder 341, and a general one can be used.

[0119] In the metering process, in order to restrict abrupt retraction of the screw 330, a set back pressure may be applied to the screw 330 by driving the injection motor 350. The back pressure on the screw 330 is detected, for example, by using a load detector 360. When the screw 330 retracts to the metering completion position and a predetermined amount of molding material is accumulated in front of the screw 330, the metering process is completed.

[0120] The position and rotation speed of the screw 330 in the metering process are set together as a series of setting conditions. For example, a metering start position, a rotation speed switching position, and a metering completion position are set. These positions are arranged in this order from the front to the rear, and represent the start and end points of the section in which the rotation speed is set. The rotation speed is set for each section. There may be one or more rotation speed switching positions. The rotation speed switching positions do not have to be set. In addition, a back pressure is set for each section.

[0121] In the filling step, the injection motor 350 is driven to move the screw 330 forward at a set moving speed, and the liquid molding material accumulated in front of the screw 330 is filled into the first cavity space 801 in the mold device 800. The position and moving speed of the screw 330 are detected, for example, by using an injection motor encoder 351. The injection motor encoder 351 detects the rotation of the injection motor 350 and sends a signal indicating the detection result to the control device 700. When the position of the screw 330 reaches a set position, switching from the filling step to the pressure holding step (so-called V / P switching) is performed. The position where the V / P switching is performed is also called the V / P switching position. The set moving speed of the screw 330 may be changed depending on the position of the screw 330, time, etc.

[0122] The position and movement speed of the screw 330 in the filling process are set together as a series of setting conditions. For example, a filling start position (also called an "injection start position"), a movement speed switching position, and a V / P switching position are set. These positions are arranged in this order from the rear side to the front, and represent the start and end points of the section for which the movement speed is set. The movement speed is set for each section. There may be one or more movement speed switching positions. The movement speed switching positions do not have to be set.

[0123] An upper limit value for 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 equal to or lower than the set pressure, the screw 330 is advanced 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 moving speed slower than the set moving speed so that the pressure of the screw 330 is equal to or lower than the set pressure, for the purpose of protecting the mold.

[0124] After the position of the screw 330 reaches the V / P switching position in the filling process, the screw 330 may be temporarily stopped at the V / P switching position, and then the V / P switching may be performed. Immediately before the V / P switching, instead of stopping the screw 330, the screw 330 may be moved forward or backward at a slow speed. In addition, the screw position detector that detects the position of the screw 330 and the screw movement speed detector that detects the movement speed of the screw 330 are not limited to the injection motor encoder 351, and general detectors may be used.

[0125] In the holding pressure step, the injection motor 350 is driven to push the screw 330 forward, and the pressure of the molding material at the front end of the screw 330 (hereinafter also referred to as "holding pressure") is maintained at a set pressure, and the molding material remaining in the cylinder 310 is pushed toward the mold device 800. The molding material that is insufficient due to cooling contraction in the mold device 800 can be replenished. The holding pressure is detected, for example, by a load detector 360. The set value of the holding pressure may be changed depending on the elapsed time from the start of the holding pressure step. The holding pressure and the holding time for which the holding pressure is held in the holding pressure step may each be set multiple times, or may be set collectively as a series of setting conditions.

[0126] In the dwelling step, the molding material in the first cavity space 801 in the mold device 800 is gradually cooled, and when the dwelling step is completed, the entrance to the first cavity space 801 is blocked by the solidified molding material. This state is called a gate seal, and prevents the molding material from flowing back from the first cavity space 801. After the dwelling step, the cooling step is started. In the cooling step, the molding material in the first cavity space 801 is solidified. In order to shorten the molding cycle time, a measuring step may be performed during the cooling step.

[0127] The first injection device 301 in this embodiment is of an in-line screw type, but may be of a pre-plastication type or the like. A pre-plastication type injection device supplies molding material molten in a plasticization cylinder to an injection cylinder, and injects the molding material from the injection cylinder into a mold device. A screw is disposed in the plasticization cylinder so as to be rotatable but unable to move forward or backward, or a screw is disposed so as to be rotatable and able to move forward or backward. Meanwhile, a plunger is disposed in the injection cylinder so as to be able to move forward or backward.

[0128] Furthermore, the first injection unit 301 of this 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. A mold clamping unit combined with the vertical first injection unit 301 may be either a vertical type or a horizontal type. Similarly, a mold clamping unit combined with the horizontal first injection unit 301 may be either a horizontal type or a vertical type.

[0129] (First moving device and second moving device) In describing the first moving device 401 and the second moving device (not shown), similarly to the description of the first injection device 301 and the second injection device 302, the movement direction of the screw 330 during filling (e.g., the negative X-axis direction) will be described as the forward direction, and the movement direction of the screw 330 during metering (e.g., the positive X-axis direction) will be described as the rearward direction.

[0130] The first moving device 401 moves the first injection device 301 forward and backward relative to the mold device 800. In addition, the first moving device 401 presses the nozzle 320 of the first injection device 301 against the mold device 800, generating a nozzle touch pressure.

[0131] The second moving device moves the second injection device 302 forward and backward relative to the mold device 800. In addition, the second moving device presses the nozzle of the second injection device 302 against the mold device 800, generating a nozzle touch pressure.

[0132] The first moving device 401 and the second moving device are disposed with an interval in the Y-axis direction. The first moving device 401 and the second moving device move the first injection device 301 and the second injection device 302 forward and backward independently.

[0133] The first moving device 401 and the second moving device are configured in the same manner. Therefore, hereinafter, the configuration of the first moving device 401 will be described, and the description of the configuration of the second moving device will be omitted. As shown in Figures 1 and 2, the first moving device 401 includes a hydraulic pump 410, a motor 420 as a drive source, a hydraulic cylinder 430 as a hydraulic actuator, and the like.

[0134] The hydraulic pump 410 has a first port 411 and a second port 412. The hydraulic pump 410 is a pump that can rotate in both directions, and by switching the rotation direction of the motor 420, it draws in hydraulic fluid (e.g., oil) from one of the first port 411 and the second port 412 and discharges it from the other port, thereby generating hydraulic pressure. Note that the hydraulic pump 410 can also draw in hydraulic fluid from a tank and discharge the hydraulic fluid from one of the first port 411 and the second port 412.

[0135] The motor 420 operates the hydraulic pump 410. The motor 420 drives the hydraulic pump 410 with a rotational direction and rotational torque according to a control signal from the control device 700. The motor 420 may be an electric motor or an electric servo motor.

[0136] The hydraulic cylinder 430 has a cylinder body 431, a piston 432, and a piston rod 433. The cylinder body 431 is fixed to the first injection device 301. The piston 432 divides the inside of the cylinder body 431 into a front chamber 435 as a first chamber and a rear chamber 436 as a second chamber. The piston rod 433 is fixed to the fixed platen 110.

[0137] The front chamber 435 of the hydraulic cylinder 430 is connected to the first port 411 of the hydraulic pump 410 via the first flow path 413. The first injection unit 301 is pushed forward by the hydraulic fluid discharged from the first port 411 being supplied to the front chamber 435 via the first flow path 413. The first injection unit 301 is moved forward, and the nozzle 320 of the first injection unit 301 is pressed against the fixed die 810. The front chamber 435 functions as a pressure chamber that generates a nozzle touch pressure of the nozzle 320 by the pressure of the hydraulic fluid supplied from the hydraulic pump 410.

[0138] On the other hand, the rear chamber 436 of the hydraulic cylinder 430 is connected to the second port 412 of the hydraulic pump 410 via the second flow path 414. The hydraulic fluid discharged from the second port 412 is supplied to the rear chamber 436 of the hydraulic cylinder 430 via the second flow path 414, thereby pushing the first injection unit 301 backward. The first injection unit 301 is moved backward, and the nozzle 320 of the first injection unit 301 is separated from the fixed mold 810.

[0139] In this embodiment, the first moving device 401 includes the hydraulic cylinder 430, but the present invention is not limited to this. For example, instead of the hydraulic cylinder 430, an electric motor and a motion conversion mechanism that converts the rotational motion of the electric motor into the linear motion of the first injection device 301 may be used.

[0140] (Control device) The control device 700 is configured, for example, by a computer, and has a CPU (Central Processing Unit) 701, a storage medium 702 such as a memory, an input interface 703, and an output interface 704 as shown in Fig. 1 and Fig. 2. The control device 700 performs various controls by causing the CPU 701 to execute a program stored in the storage medium 702. The control device 700 also receives signals from the outside via the input interface 703, and transmits signals to the outside via the output interface 704.

[0141] The control device 700 repeatedly performs a metering process, a mold closing process, a pressure increase process, a mold clamping process, a filling process, a pressure holding process, a cooling process, a pressure release process, a mold opening process, an ejection process, a mold rotation process, and the like, thereby repeatedly manufacturing the first molded product 21 and the second molded product 22. A series of operations for obtaining the first molded product 21 and the second molded product 22, for example, an operation from the start of a metering process to the start of the next metering process, is also called a "shot" or a "molding cycle." The time required for one shot is also called a "molding cycle time" or a "cycle time."

[0142] One molding cycle includes, for example, a metering process, a mold closing process, a pressure increase process, a mold clamping process, a filling process, a pressure holding process, a cooling process, a pressure release process, a mold opening process, an ejection process, and a mold rotation process, in this order. The order here refers to the order in which each process starts. The filling process, the pressure holding process, and the cooling process are performed during the mold clamping process. The start of the mold clamping process may coincide with the start of the filling process. The end of the pressure release process coincides with the start of the mold opening process.

[0143] In addition, in order to shorten the molding cycle time, a plurality of processes may be performed simultaneously. For example, the metering process may be performed during the cooling process of the previous molding cycle, or during the mold clamping process. In this case, the mold closing process may be performed at the beginning of the molding cycle. The filling process may be started during the mold closing process. The ejection process may be started during the mold opening process. In the case where an opening / closing valve for opening and closing the flow path of the nozzle 320 is provided, the mold opening process may be started during the metering process. This is because even if the mold opening process is started during the metering process, the molding material will not leak from the nozzle 320 if the opening / closing valve closes the flow path of the nozzle 320.

[0144] Incidentally, one molding cycle may include steps other than the metering step, mold closing step, pressure increase step, mold clamping step, filling step, pressure holding step, cooling step, pressure release step, mold opening step, ejection step, and mold rotation step.

[0145] For example, after the dwelling step is completed, a pre-metering suck-back step may be performed in which the screw 330 is retracted to a preset metering start position before the metering step is started. This can reduce the pressure of the molding material accumulated in front of the screw 330 before the metering step starts, and can prevent the screw 330 from suddenly retracting at the start of the metering step.

[0146] Furthermore, after the metering step is completed, a post-metering suck-back step may be performed in which the screw 330 is retracted to a preset filling start position (also called the "injection start position") before the filling step is started. This can reduce the pressure of the molding material accumulated in front of the screw 330 before the filling step is started, and can prevent the molding material from leaking from the nozzle 320 before the filling step is started.

[0147] The control device 700 is connected to an operation device 750 that accepts input operations by a user and a display device 760 that displays a screen. The operation device 750 and the display device 760 may be configured, for example, by 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. For example, the screen of the touch panel 770 may display information such as the settings of the injection molding machine 10 and the current state of the injection molding machine 10. In addition, for example, an operation unit such as a button that accepts an input operation by a user and an input field may be displayed on the screen of the touch panel 770. The touch panel 770 as the operation device 750 detects an input operation on the screen by the user and outputs a signal corresponding to the input operation to the control device 700. Thereby, for example, the user can operate the operation unit provided on the screen while checking the information displayed on the screen to perform settings of the injection molding machine 10 (including input of a setting value). In addition, the user can operate the operation unit provided on the screen to perform an operation of the injection molding machine 10 corresponding to the operation unit. The operation of the injection molding machine 10 may be, for example, the operation (including stopping) of the clamping device 100, the first ejector device 201, the second ejector device 202, the first injection device 301, the second injection device 302, the first moving device 401, the second moving device (not shown), etc. The operation of the injection molding machine 10 may be, for example, switching of a screen displayed on the touch panel 770 serving as the display device 760.

[0148] Incidentally, the operation device 750 and the display device 760 of this embodiment have been described as being integrated as the touch panel 770, but they may be provided independently. Also, a plurality of operation devices 750 may be provided. The operation device 750 and the display device 760 are disposed on the operation side (Y-axis negative direction) of the mold clamping unit 100 (more specifically, the fixed platen 110).

[0149] Next, referring to FIG. 8, the change over time of the first filling pressure P1, the second filling pressure P2, and the actual values ​​of the mold clamping force F will be described. The first filling pressure P1 is a pressure for filling the first cavity space 801 with the molding material. The second filling pressure P2 is a pressure for filling the second cavity space 802 with the molding material. A pressure detector for detecting the actual value of the first filling pressure P1 and a pressure detector for detecting the actual value of the second filling pressure P2 are provided separately. In this embodiment, the pressure detector is an internal mold pressure sensor, but may be a nozzle pressure sensor or a load detector 360. In this embodiment, the mold clamping force detector for detecting the actual value of the mold clamping force F is a tie bar strain detector 141, but is not particularly limited.

[0150] When the first injection device 301 starts injection, the actual value of the first filling pressure P1 gradually increases and reaches a maximum. The timing when the first injection device 301 starts injection may be referred to as a first injection start timing t1a. Also, the timing when the actual value of the first filling pressure P1 reaches a maximum value may be referred to as a first peak timing t1b.

[0151] When the second injection device 302 starts injection, the actual value of the second filling pressure P2 gradually increases and reaches a maximum. The timing when the second injection device 302 starts injection may be referred to as second injection start timing t2a. Also, the timing when the actual value of the second filling pressure P2 reaches a maximum value may be referred to as second peak timing t2b.

[0152] As shown in FIG. 8(A), when the first injection start timing t1a and the second injection start timing t2a are the same, the first peak timing t1b and the second peak timing t2b may become the same. The first filling pressure P1 and the second filling pressure P2 act in a direction to open the fixed mold 810 and the movable mold 820 against the mold clamping force. Therefore, when the first peak timing t1b and the second peak timing t2b become the same, the fixed mold 810 and the movable mold 820 may open. If the opening amount is too large, burrs are generated. Burrs are a phenomenon in which the molding material leaks between the fixed mold 810 and the movable mold 820 and solidifies.

[0153] After the mold clamping process starts, the actual value of the mold clamping force F is stable until the molding material reaches the parting surface between the fixed mold 810 and the movable mold 820. Thereafter, when the fixed mold 810 and the movable mold 820 open, the amount of opening is equal to the amount of extension of the tie bar 140, and the actual value of the mold clamping force F rises according to the amount of extension. Therefore, the increase ΔF represents the amount of opening between the fixed mold 810 and the movable mold 820 in the mold clamping process. The larger the amount of opening, the larger the increase ΔF.

[0154] 8B, the control device 700 of this embodiment provides an interval between the first peak timing t1b and the second peak timing t2b by providing an interval between the first injection start timing t1a and the second injection start timing t2a. The interval between t1a and t2a and the interval between t1b and t2b are determined so that the increase width ΔF of the actual value of the mold clamping force F is equal to or smaller than an upper limit. The upper limit of the increase width ΔF is determined so that no flash occurs.

[0155] Providing an interval between t1b and t2b includes controlling a setting regarding the interval between t1b and t2b. The setting regarding the interval between t1b and t2b may include at least one of the interval between t1b and t2b, t1b itself, and t2b itself. The interval between t1b and t2b, t1b or t2b may be controlled to provide an interval by setting these, but instead of setting these directly, the interval between t1b and t2b, t1b or t2b may be set as a result of setting the operation timing and forward speed of the screw, and operating according to the settings. As an example of the setting regarding the interval between t1b and t2b, the setting regarding the interval between t1a and t2a may be used.

[0156] The setting of the interval between t1b and t2b preferably includes at least one of the interval between t1a and t2a, t1a itself, and t2a itself, but may not necessarily be t1a or t2a itself, but may be the actual value of the filling pressure P1 or P2 at which the first injection device 301 or the second injection device 302 starts injection. t1a and t2a are the operation timing of the machine, so they can be set directly. In addition, the setting of the interval between t1b and t2b, t1b, or t2b may be the forward speed of the screw 330 in at least one of the first injection device 301 and the second injection device 302. The slower the forward speed of the screw 330, the slower t1b or t2b becomes. If it is possible to control the interval between t1b and t1b, other controls including the interval, timing, or operation conditions for t1a, t2a, t1b, or t2b can be adopted.

[0157] As described above, the control device 700 places an interval between the first peak timing t1b and the second peak timing t2b by placing an interval between the first injection start timing t1a and the second injection start timing t2a. This makes it possible to prevent the fixed mold 810 and the movable mold 820 from opening too much in the mold clamping process, thereby suppressing the occurrence of burrs. In addition, the mold clamping motor 160 can be made smaller.

[0158] The interval between t1a and t2a and the interval between t1b and t2b may be determined so that the increase width ΔF of the actual value of the mold clamping force F is equal to or less than the upper limit. If ΔF is too low, the risk of gas burning increases, so a lower limit may be additionally set for ΔF to prevent gas burning. Gas burning is a phenomenon in which the molding material flows into the first cavity space 801 or the second cavity space 802, compressing the gas in the first cavity space 801 or the second cavity space 802 and generating heat, carbonizing the molding material. By setting the lower limit, a gas release path can be secured, and the occurrence of gas burning can be suppressed.

[0159] In addition, either t1a or t2a may come first. The user may input which of t1a and t2a comes first, or the control device 700 may automatically set it by acquiring information (e.g., type of resin or cooling time) about the first molded product 21 and the second molded product 22. Of the first molded product 21 and the second molded product 22, it is preferable that the injection start timing of the molded product with the longer cooling time comes first. If the injection start timing of the molded product with the longer cooling time comes first, the molding cycle time is shorter than when the order of the injection start timings is reversed.

[0160] The control device 700 may obtain the interval between the first injection start timing t1a and the second injection start timing t2a based on the actual value of the mold clamping force F. The control device 700 repeats the molding cycle while changing the interval between t1a and t2a, and obtains the interval between t1a and t2a at which the increase width ΔF of the actual value of the mold clamping force F becomes equal to or smaller than the upper limit. At this time, the actual values ​​of the first filling pressure P1 and the second filling pressure P2 do not need to be taken into consideration.

[0161] The control device 700 may obtain the interval between the first injection start timing t1a and the second injection start timing t2a based on the actual values ​​of both the first filling pressure P1 and the second filling pressure P2. The control device 700 repeats the molding cycle while changing the interval between t1a and t2a, and obtains the interval between t1a and t2a at which the sum of P1 and P2 is equal to or less than the upper limit. At this time, the actual value of the mold clamping force F does not need to be taken into consideration.

[0162] Alternatively, the control device 700 may determine the interval between the first injection start timing t1a and the second injection start timing t2a based on the actual value of only one of the first filling pressure P1 and the second filling pressure P2. The control device 700 may determine the timing to start another injection after starting injection of only one of the first injection device 301 and the second injection device 302, based on the actual value of the filling pressure that increases due to the injection. Specifically, the interval between t1a and t2a is determined so that another injection starts after the actual value of the filling pressure reaches a maximum value due to the start of one injection.

[0163] The control device 700 may obtain the interval between t1a and t2a based on at least one of the actual values ​​of the mold clamping force F and the first filling pressure P1 and the second filling pressure P2, and then repeat the molding cycle using the obtained interval between t1a and t2a, or may notify the user that the interval between t1a and t2a should be changed. After notifying the user, the control device 700 may repeat the molding cycle using the obtained interval between t1a and t2a when it detects that a predetermined operation has been performed by the user.

[0164] The control device 700 may monitor the increase width ΔF of the actual value of the mold clamping force F, and perform control to issue an alarm when the increase width ΔF exceeds an upper limit value. The control device 700 performs control to issue an alarm by controlling an image display device, a warning light, a buzzer, or the like. In addition to the control to issue an alarm for the upper limit value, the control device 700 may additionally perform control to issue an alarm when the increase width ΔF falls below a lower limit value. The upper limit value and the lower limit value may be configured to be input by a user, or may be configured to be automatically set by the control device 700 by acquiring information about the first molded product 21 and the second molded product 22 (for example, whether molding is unnecessary).

[0165] The control device 700 may monitor whether there is a delay in the filling process after starting injection from only one of the first injection device 301 and the second injection device 302. In the filling process, the screw 330 is advanced at a set moving speed, but if the pressure of the screw 330 exceeds the set pressure, the screw 330 is advanced at a speed slower than the set moving speed for the purpose of protecting the mold. As a result, the filling process may be delayed. When the control device 700 detects a delay in the filling process, it may lengthen the interval between t1a and t2a, or may notify that the interval between t1a and t2a should be lengthened.

[0166] Instead of setting the interval between t1a and t2a, the subsequent timing (e.g., t2a) of t1a and t2a may be controlled regardless of the preceding timing (e.g., t1a). Below, a representative case will be described in which t1a precedes t2a, that is, the first injection unit 301 starts injection before the second injection unit 302. Note that t2a may also precede t1a. That is, the second injection unit 302 may start injection before the first injection unit 301. Setting the interval between t1a and t2a includes determining the interval, finding the interval, changing the interval, or lengthening the interval.

[0167] In the case where the first injection device 301 starts injection before the second injection device 302, t2a may be set based on the completion time of the filling process of the first injection device 301. t2a may be set to the completion time of the filling process of the first injection device 301, or may be set a predetermined time earlier than the completion time, or may be set a predetermined time later than the completion time. Instead of the completion time of the filling process, the completion time of the pressure retention process may be used as the reference.

[0168] In addition, when the first injection unit 301 starts injection before the second injection unit 302, t2a may be set to the time when the first filling pressure P1 satisfies a predetermined condition. Alternatively, when the first injection unit 301 starts injection before the second injection unit 302, t2a may be set to the time when the mold clamping force satisfies a predetermined condition.

[0169] When the first injection device 301 starts injection before the second injection device 302, the control device 700 may receive a user's selection as to whether t2a should be set during the filling process of the first injection device 301 or during the pressure holding process of the first injection device 301. The control device 700 receives the user's selection on the screen of the touch panel 770, for example.

[0170] In addition, the mold device 800 may have a third cavity space (not shown) in addition to the first cavity space 801 and the second cavity space 802. The injection molding machine 10 may have a third injection device (not shown) in addition to the first injection device 301 and the second injection device 302. The third injection device fills the third cavity space with the molding material by touching the mold device 800 and injecting the molding material into the inside of the mold device 800. The pressure at which the molding material is filled into the third cavity space may be referred to as a third filling pressure P3. The timing at which the actual value of the third filling pressure P3 reaches a maximum value may be referred to as a third peak timing t3b. The timing at which the third injection device starts injection may be referred to as a third injection start timing t3a.

[0171] In this case, it is preferable that the control device 700 space t1a, t2a, and t3a from each other, and space t1b, t2b, and t3b from each other. However, any two selected from t1a, t2a, and t3a may be spaced. For example, if t1a and t2a are different, t3a may be the same as t1a or t2a. Also, any two selected from t1b, t2b, and t3b may be spaced. For example, if t1b and t2b are different, t3b may be the same as t1b or t2b. The mold device 800 may further have a fourth cavity space (not shown), and the injection molding machine 10 may further have a fourth injection device (not shown).

[0172] In addition, in this embodiment, the movable mold 820 is attached to the rotating platen 520 and rotates together with the rotating platen 520, but the technology of the present disclosure is not limited to this. The rotating platen 520 may be omitted, and the movable mold 820 may be fixed to the movable platen 120. Alternatively, the movable mold 820 may be attached to the movable platen 120 so as to be slidable in a direction perpendicular to the mold opening and closing direction. It is sufficient that the mold device 800 has a first cavity space 801 and a second cavity space 802, and the injection molding machine 10 has a first injection device 301 and a second injection device 302.

[0173] Next, a mold assembly 800 according to a modified example will be described with reference to FIG. 9. The following mainly describes the differences from the above embodiment. The contents of the above embodiment are applicable to this modified example. The mold assembly 800 has a hot runner 880 in addition to a fixed mold 810 and a movable mold 820. The hot runner 880 has a heater 881 that heats the flow path of the molding material, a first valve gate 882 that opens and closes the entrance to the first cavity space 801, and a second valve gate 883 that opens and closes the entrance to the second cavity space 802.

[0174] The first valve gate 882 is an example of a first opening and closing part. The first opening and closing part opens and closes the first cavity space 801 with respect to an injection port 809 of the molding material in the mold device 800. The position of the first opening and closing part is not particularly limited. When the injection device 300 injects the molding material into the mold device 800 and the first opening and closing part opens the flow path of the molding material, the molding material flows into the first cavity space 801.

[0175] The second valve gate 883 is an example of a second opening and closing part. The second opening and closing part opens and closes the second cavity space 802 with respect to the injection port 809 of the molding material in the mold device 800. The position of the second opening and closing part is not particularly limited. When the injection device 300 injects the molding material into the mold device 800 and the second opening and closing part opens the flow path of the molding material, the molding material flows into the second cavity space 802.

[0176] 8 is also valid for the mold device 800 of this modified example. However, in this modified example, t1a is the first opening timing for opening the first valve gate 882, and t2a is the second opening timing for opening the second valve gate 883. Note that t1b is the first peak timing at which the actual value of the first filling pressure P1 reaches a maximum value, and t2b is the second peak timing at which the actual value of the second filling pressure P2 reaches a maximum value.

[0177] 8A, if the first opening timing t1a and the second opening timing t2a are the same, the first peak timing t1b and the second peak timing t2b may become the same. As a result, the fixed mold 810 and the movable mold 820 may open. If the opening amount is too large, burrs may occur.

[0178] 8B, the control device 700 of this embodiment provides an interval between the first peak timing t1b and the second peak timing t2b by providing an interval between the first opening timing t1a and the second opening timing t2a. The interval between t1a and t2a and the interval between t1b and t2b are determined so that the increase width ΔF of the actual value of the mold clamping force F is equal to or smaller than an upper limit. The upper limit of the increase width ΔF is determined so that burrs are not generated.

[0179] As described above, the control device 700 places an interval between the first opening timing t1a and the second opening timing t2a, thereby placing an interval between the first peak timing t1b and the second peak timing t2b. This makes it possible to prevent the fixed mold 810 and the movable mold 820 from opening too much in the mold clamping process, thereby suppressing the occurrence of burrs. In addition, the mold clamping motor 160 can be made smaller.

[0180] The interval between t1a and t2a, and the interval between t1b and t2b may be determined so that the increase ΔF in the actual value of the mold clamping force F is equal to or less than the upper limit. If ΔF is too low, the risk of gas burning increases, so a lower limit may be additionally set for ΔF to prevent gas burning. Setting a lower limit ensures a gas release path and suppresses the occurrence of gas burning.

[0181] In addition, either t1a or t2a may come first. The user may input which of t1a and t2a comes first, or the control device 700 may automatically set it by acquiring information about the first molded product 21 and the second molded product 22 (for example, the type of resin or the cooling time).

[0182] The control device 700 may obtain a setting for spacing the first opening timing t1a and the second opening timing t2a based on the actual value of the mold clamping force F. The control device 700 repeats the molding cycle while changing the setting for spacing t1a and t2a, and obtains a setting for spacing t1a and t2a such that the increase width ΔF of the actual value of the mold clamping force F is equal to or smaller than the upper limit. At this time, the actual values ​​of the first filling pressure P1 and the second filling pressure P2 do not need to be taken into consideration.

[0183] The control device 700 may obtain a setting for spacing the first opening timing t1a and the second opening timing t2a based on the actual values ​​of both the first filling pressure P1 and the second filling pressure P2. The control device 700 repeats the molding cycle while changing the setting for spacing t1a and t2a, and obtains a setting for spacing t1a and t2a such that the sum of P1 and P2 is equal to or less than the upper limit. At this time, the actual value of the mold clamping force F does not need to be taken into consideration.

[0184] Alternatively, the controller 700 may determine a setting for spacing the first opening timing t1a and the second opening timing t2a based on the actual value of only one of the first filling pressure P1 and the second filling pressure P2. The controller 700 may determine a timing for opening the other valve gate after opening only one of the first valve gate 882 and the second valve gate 883, based on the actual value of the filling pressure that increases as a result of the opening. Specifically, the controller 700 determines a setting for spacing t1a and t2a such that the other valve gate is opened after the actual value of the filling pressure reaches a maximum value due to the opening of one valve gate.

[0185] The control device 700 may determine a setting for spacing t1a and t2a based on at least one of the actual values ​​of the mold clamping force F and the first and second filling pressures P1 and P2, and then repeat the molding cycle using the determined setting, or may notify the user that the setting should be changed. After notifying the user, the control device 700 may repeat the molding cycle using the determined setting when it detects that a predetermined operation has been performed by the user.

[0186] In addition to the first cavity space 801 and the second cavity space 802, the mold device 800 may have a third cavity space (not shown) and may have a third opening and closing part (not shown). The third opening and closing part opens and closes the third cavity space to an injection port 809 of the molding material in the mold device 800. The timing at which the actual value of the third filling pressure P3 reaches the maximum value may be referred to as a third peak timing t3b. The timing at which the third opening and closing part opens the flow path of the molding material may be referred to as a third opening timing t3a.

[0187] In this case, the control device 700 preferably places a distance between t1a, t2a, and t3a, and thus places a distance between t1b, t2b, and t3b. However, any two selected from t1a, t2a, and t3a may be spaced apart. For example, if t1a and t2a are different, t3a may be the same as t1a or t2a. Also, any two selected from t1b, t2b, and t3b may be spaced apart. For example, if t1b and t2b are different, t3b may be the same as t1b or t2b. The mold device 800 may further have a fourth cavity space (not shown) and may further have a fourth opening and closing portion (not shown).

[0188] In addition, although the mold apparatus 800 has a hot runner 880 in this embodiment, it is not necessary to have the hot runner 880. It is sufficient that the mold apparatus 800 has a first cavity space 801 and a second cavity space 802, and has a first opening and closing part and a second opening and closing part. The contents of this modification are also applicable to the molding mold described in Patent Document 2.

[0189] Although the embodiments of the control device for an injection molding machine, the injection molding machine, and the control method for an injection molding machine according to the present invention have been described above, the present invention is not limited to the above-mentioned embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Naturally, these also fall within the technical scope of the present invention. [Explanation of symbols]

[0190] 10 injection molding machine 700 Control device 800 Mold Equipment 801 First cavity space 802 Second cavity space 810 Fixed mold 820 Movable Mold

Claims

1. 1. A control device for an injection molding machine, which, when a mold device having a fixed mold and a movable mold is clamped, fills a molding material into each of a first cavity space and a second cavity space that are separately formed between the fixed mold and the movable mold, comprising: A control device for an injection molding machine, which provides an interval between a first peak timing at which the filling pressure for filling the first cavity space with molding material reaches a maximum value and a second peak timing at which the filling pressure for filling the second cavity space with molding material reaches a maximum value when the mold is clamped.

2. A first injection unit that injects a molding material into the inside of the mold unit fills the first cavity space with the molding material; a second injection unit that injects a molding material into the inside of the mold unit fills the second cavity space with the molding material; providing an interval between a first injection start timing at which the first injection device starts injecting the molding material and a second injection start timing at which the second injection device starts injecting the molding material, thereby providing an interval between the first peak timing and the second peak timing; The control device for an injection molding machine according to claim 1 ,

3. 3. The control device for an injection molding machine according to claim 2, wherein the interval between the first injection start timing and the second injection start timing is calculated based on an actual value of at least one of a mold clamping force and a filling pressure.

4. Controlling a first opening / closing unit that opens and closes the first cavity space with respect to an injection port of a molding material in the mold device; Controlling a second opening / closing unit that opens and closes the second cavity space relative to an injection port of a molding material in the mold device; providing an interval between a first opening timing at which the first opening / closing unit is opened and a second opening timing at which the second opening / closing unit is opened, thereby providing an interval between the first peak timing and the second peak timing; 2. The control device for an injection molding machine according to claim 1, further comprising:

5. 5. The control device for an injection molding machine according to claim 4, wherein the interval between the first opening timing and the second opening timing is calculated based on an actual value of at least one of a mold clamping force and a filling pressure.

6. An injection molding machine comprising the control device according to any one of claims 1 to 5.

7. 1. A control method for an injection molding machine, comprising the steps of: filling a first cavity space and a second cavity space formed between a fixed mold and a movable mold with a molding material when a mold device having a fixed mold and a movable mold is clamped, the control method comprising the steps of: A control method for an injection molding machine, comprising: providing an interval between a first peak timing at which the filling pressure for filling the first cavity space with molding material reaches a maximum value and a second peak timing at which the filling pressure for filling the second cavity space with molding material reaches a maximum value during mold clamping.

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