Injection molding equipment

Abstract

To grasp a mixing ratio of two liquids and the like to prevent a quality of a molded article from decreasing in an injection molding using two-liquid type molding materials.SOLUTION: An injection molding apparatus has: a cylindrical cylinder; an agitation member disposed in the cylinder; a mixing unit for mixing a first liquid containing a thermosetting material flowed into the cylinder and a second liquid containing an initiator to initiate polymerization reaction of the thermosetting material using the agitation member to generate a mixed material; an injection unit having a nozzle and injecting the mixed material from the nozzle toward a cavity partitioned by a fixed mold and a movable mold: and a detection unit for detecting a condition in the cylinder.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an injection molding apparatus. [Background technology]

[0002] Patent Document 1 discloses a two-component silicone rubber injection molding method. In this method, first and second liquids, which are silicone rubber materials, are mixed in a spiral groove formed in a rotating scroll and then pressure-fed to an injection cylinder, from which the material is injected into a mold cavity, and the material injected into the cavity is heated to harden, thereby molding the silicone rubber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-158127 Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned in the above document, in injection molding using two-component molding materials, variations in the mixing ratio and mixing state of the two components can lead to a deterioration in the quality of the molded product. Although it is possible to determine the variations in the mixing ratio and mixing state of the two components after the fact by inspecting the molded product, this method of determining the mixing ratio and mixing state after the fact does not allow for the deterioration in the quality of the molded product to be detected and addressed in advance. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided an injection molding apparatus, the injection molding apparatus comprising: a mixing unit having a cylindrical cylinder and a stirring member disposed within the cylinder, the mixing unit using the stirring member to mix a first liquid containing a thermosetting material flowing into the cylinder with a second liquid containing a polymerization initiator that starts a polymerization reaction of the thermosetting material to produce a mixed material; an injection unit having a nozzle and injecting the mixed material from the nozzle toward a cavity defined by a fixed mold and a movable mold; and a detection unit detecting a state inside the cylinder. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a front view showing a schematic configuration of an injection molding apparatus according to a first embodiment. [Figure 2] Cross-sectional view taken along line II-II in Figure 1. [Figure 3] FIG. 3 is a perspective view showing the configuration of a first connecting member of the first embodiment. [Figure 4] FIG. 3 is an exploded perspective view showing the configuration of a second connecting member in the first embodiment. [Figure 5] 6 is a graph showing pressure measured by a first pressure sensor of the first detection unit. [Figure 6] 10 is a graph showing pressure measured by a third pressure sensor of the first detection unit. [Figure 7] 10 is a first graph showing pressures measured by the pressure sensors of the second detection unit. [Figure 8] 10 is a second graph showing pressures measured by the pressure sensors of the second detection unit. [Figure 9] 4 is a flowchart showing the contents of an injection process according to the first embodiment. [Figure 10] FIG. 10 is a front view showing a schematic configuration of an injection molding apparatus according to a second embodiment. [Figure 11] 10 is a flowchart showing the contents of an injection process according to a second embodiment. [Figure 12] FIG. 10 is a cross-sectional view showing the configuration of a nozzle according to a third embodiment. [Figure 13] FIG. 10 is a cross-sectional view showing the configuration of a nozzle according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] A. First embodiment: FIG. 1 is a front view showing a schematic configuration of an injection molding apparatus 10 in a first embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. A mold 20 is attached to the injection molding apparatus 10 shown in FIG. 1. The injection molding apparatus 10 injects a two-component thermosetting material into the mold 20 to form a molded product. The thermosetting material includes at least one of a thermosetting resin and a thermosetting elastomer. In this embodiment, the injection molding apparatus 10 injects two-component silicone rubber into the mold 20 as the two-component thermosetting material.

[0008] The molding die 20 has a fixed die 21 and a movable die 22. The movable die 22 is disposed opposite the fixed die 21. As shown in FIG. 2, the molding die 20 has a cavity Cv defined by the fixed die 21 and the movable die 22 when the fixed die 21 and the movable die 22 come into contact with each other. The cavity Cv is a space having a shape corresponding to the shape of the molded product. The molding die 20 is provided with a heater 28 for heating and curing the two-component thermosetting material injected into the cavity Cv. The molding die 20 is made of a metal material, a resin material, or a ceramic material. Note that a molding die 20 made of a metal material is sometimes called a metal mold.

[0009] As shown in FIG. 1, the injection molding apparatus 10 includes a first tank 100, a first pump 110, a second tank 200, a second pump 210, a mixing unit 300, a first detection unit 350, an injection unit 400, a second detection unit 450, a mold clamping unit 500, and a control unit 600. In this embodiment, the mixing unit 300, the injection unit 400, and the mold clamping unit 500 are disposed on a base 15. The first tank 100, the first pump 110, the second tank 200, and the second pump 210 are disposed adjacent to the base 15. The control unit 600 is disposed within the base 15. Note that in FIG. 1, portions of the mixing unit 300 and the injection unit 400 are shown in cross section to facilitate understanding of the technology.

[0010] The first tank 100 stores a first liquid. The first liquid contains a base material of a two-component thermosetting material. In this embodiment, the first liquid contains a silicone polymer as a base material of a two-component silicone rubber.

[0011] The first pump 110 is connected to the first tank 100. The first pump 110 pumps the first liquid stored in the first tank 100 to the mixing section 300. In this embodiment, the first pump 110 is configured as a positive displacement pump. More specifically, the first pump 110 is configured as a screw pump. The first pump 110 is driven under the control of the control section 600. In this embodiment, the first liquid discharged from the first pump 110 is supplied to the mixing section 300 via a first pipe 120 connecting the first pump 110 and the mixing section 300. It is preferable that the first pump 110 be capable of delivering the first liquid to the mixing section 300 at a fixed amount and suppressing pulsating flow of the first liquid. Note that in other embodiments, the first pump 110 may be configured as a positive displacement pump other than a screw pump, such as a gear pump, or may be configured as a turbo pump.

[0012] The second tank 200 stores a second liquid. The second liquid contains a polymerization initiator that starts the polymerization reaction of the two-component thermosetting material. By combining a predetermined amount of the first liquid and a predetermined amount of the second liquid, the polymerization reaction of the two-component thermosetting material can be started.

[0013] The second pump 210 is connected to the second tank 200. The second pump 210 pumps the second liquid stored in the second tank 200 to the mixing section 300. In this embodiment, the second pump 210 is configured as a positive displacement pump. More specifically, the second pump 210 is configured as a screw pump. The second pump 210 is driven under the control of the control section 600. In this embodiment, the second liquid delivered from the second pump 210 is supplied to the mixing section 300 via a second pipe 220 connecting the second pump 210 and the mixing section 300. It is preferable that the second pump 210 be capable of delivering the second liquid to the mixing section 300 at a fixed rate and suppressing pulsating flow of the second liquid. Note that in other embodiments, the second pump 210 may be configured as a positive displacement pump other than a screw pump, such as a gear pump, or may be configured as a turbo pump.

[0014] The mixing section 300 mixes the first liquid and the second liquid and supplies the mixed liquid to the injection section 400. In this embodiment, the mixing section 300 includes a flow path member 310, a static mixer 320, a first connecting member 330, and a second connecting member 340.

[0015] In this embodiment, the flow path member 310 has a rectangular parallelepiped outer shape. The first pipe 120 and the second pipe 220 are connected to the flow path member 310. A first flow path 311, a second flow path 312, and a junction flow path 313 are provided inside the flow path member 310.

[0016] One end of the first flow path 311 is connected to the first pump 110 via the first pipe 120, and the other end of the first flow path 311 is connected to one end of a junction flow path 313. One end of the second flow path 312 is connected to the second pump 210 via the second pipe 220, and the other end of the second flow path 312 is connected to one end of the junction flow path 313. The other end of the junction flow path 313 is connected to the static mixer 320. The first liquid that flows into the first flow path 311 from the first pipe 120 flows toward the junction flow path 313. The second liquid that flows into the second flow path 312 from the second pipe 220 flows toward the junction flow path 313. The first and second liquids join at the junction flow path 313 and flow toward the static mixer 320.

[0017] The static mixer 320 includes a mixing cylinder 321 and an agitator 325. The mixing cylinder 321 is a cylindrical member. In this embodiment, the mixing cylinder 321 is configured in a cylindrical shape. One end of the mixing cylinder 321 is connected to the flow path member 310 via a first connecting member 330. The other end of the mixing cylinder 321 is connected to the side surface of the injection cylinder 410 (described later) via a second connecting member 340. The mixing cylinder 321 communicates with the merging flow path 313 and the inside of the injection cylinder 410. The specific configurations of the first connecting member 330 and the second connecting member 340 will be described later. The mixing cylinder 321 may also be simply referred to as a cylinder.

[0018] The stirring member 325 is disposed within the mixing cylinder 321. In this embodiment, the stirring member 325 is composed of a plurality of mixing elements connected to one another. The plurality of mixing elements are arranged side by side from one end of the mixing cylinder 321 to the other. Each mixing element has a shape obtained by twisting a rectangular plate 180 degrees. The twist rotation directions of adjacent mixing elements are different from each other. Each mixing element is fixed to the inner wall surface of the mixing cylinder 321 and is stationary relative to the mixing cylinder 321. Note that, for ease of understanding the technology, FIG. 1 shows the stirring member 325 having four mixing elements; however, the number of mixing elements of the stirring member 325 may be, for example, several or several tens.

[0019] The static mixer 320 mixes the first and second liquids that have flowed into the mixing cylinder 321 through the dividing, diverging, and reversing actions of each mixing element of the agitator 325. The dividing action is the action of dividing the fluid flow. The diverging action is the action of moving the fluid from the central axis of the mixing cylinder 321 toward the inner wall surface, or from the inner wall surface toward the central axis. The reversing action is the action of reversing the direction of the vortex of the fluid that flows in a vortex shape around the central axis of the mixing cylinder 321. In the following description, the mixture of the first and second liquids is referred to as the mixed material. In this embodiment, the mixed material is in a gel state. Note that in other embodiments, the mixed material may be in a liquid state.

[0020] In this embodiment, mixing cylinder 321 and stirring member 325 are made of a resin material such as polytetrafluoroethylene (PTFE) or polyvinyl chloride (PVC). In other embodiments, mixing cylinder 321 and stirring member 325 may be made of a metal material such as stainless steel or titanium alloy, or may be made of a ceramic material. Mixing cylinder 321 and stirring member 325 may be made of different materials.

[0021] The first detection unit 350 is provided in the mixing cylinder 321. In this embodiment, the first detection unit 350 includes a first pressure sensor 351A, a second pressure sensor 351B, and a third pressure sensor 351C. The first pressure sensor 351A is provided in the upstream portion of the mixing cylinder 321, that is, near the connection between the mixing cylinder 321 and the flow path member 310. The second pressure sensor 351B is provided in the midstream portion of the mixing cylinder 321. The third pressure sensor 351C is provided in the downstream portion of the mixing cylinder 321, that is, near the connection between the mixing cylinder 321 and the injection cylinder 410.

[0022] Each pressure sensor 351A to 351C detects the pressure of the material to be mixed inside the mixing cylinder 321. Information related to the pressure detected by each pressure sensor 351A to 351C is transmitted to the control unit 600. In the following description, when the pressure sensors 351A to 351C are not particularly distinguished from one another, each pressure sensor 351A to 351C may be simply referred to as a pressure sensor 351. The number of pressure sensors 351 provided in the mixing cylinder 321 is not limited to three, and may be one, or two or more. The first detection unit 350 may be simply referred to as a detection unit.

[0023] The injection unit 400 measures and injects the mixed material. In this embodiment, the injection unit 400 includes an injection cylinder 410, a plunger 420, a plunger driver 430, and a nozzle 440 shown in FIG.

[0024] The injection cylinder 410 is a cylindrical member. In this embodiment, the injection cylinder 410 is configured in a cylindrical shape. The mixed material flowing from the mixing cylinder 321 is stored inside the injection cylinder 410. A nozzle 440 is connected to the end of the injection cylinder 410. The plunger 420 is disposed inside the injection cylinder 410. The plunger 420 is a columnar member. The outer peripheral surface of the plunger 420 is provided along the inner wall surface of the injection cylinder 410. The plunger driving unit 430 moves the plunger 420 along the central axis of the injection cylinder 410. The plunger driving unit 430 moves the plunger 420 toward the nozzle 440, thereby injecting the mixed material inside the injection cylinder 410 from the nozzle 440. In this embodiment, the plunger driving unit 430 is configured by combining a motor and a reducer. The plunger driving unit 430 is driven under the control of the control unit 600.

[0025] As shown in Fig. 2, in this embodiment, the nozzle 440 includes a nozzle tip 441, a nozzle flow path member 445, and a nozzle cover 460. The nozzle tip 441 is a cylindrical member. A nozzle opening 442 for injecting the mixed material is provided at the tip of the nozzle tip 441. The rear end of the nozzle tip 441 is fixed to the injection cylinder 410 via the nozzle flow path member 445. The nozzle opening 442 communicates with the injection cylinder 410 via a flow path provided in the nozzle flow path member 445.

[0026] The tip of the nozzle tip 441 contacts the fixed mold 21. More specifically, an opening 26 that communicates with the cavity Cv is formed in the fixed mold 21, and the tip of the nozzle tip 441 contacts the surface 25 of the fixed mold 21 on which the opening 26 is formed. The mixed material injected from the nozzle opening 442 is injected into the cavity Cv through the opening 26. In the following description, the surface 25 of the fixed mold 21 on which the opening 26 is formed will be referred to as the opening forming surface 25. In this embodiment, the opening forming surface 25 is configured to be flat.

[0027] In this embodiment, a seal member 470 is disposed between the tip of the nozzle tip 441 and the opening-forming surface 25, and the tip of the nozzle tip 441 contacts the opening-forming surface 25 via the seal member 470. The seal member 470 is an annular plate member formed of a material softer than the material of the nozzle tip 441. The nozzle tip 441 is formed of, for example, stainless steel, and the seal member 470 is formed of, for example, aluminum. The thickness of the seal member 470 is, for example, 0.01 mm to 0.1 mm. The seal member 470 is sandwiched and crushed between the tip of the nozzle tip 441 and the opening-forming surface 25. The seal member 470 seals the gap between the tip of the nozzle tip 441 and the opening-forming surface 25. To prevent the seal member 470 from shifting position, the seal member 470 is preferably fixed to the tip of the nozzle tip 441 or the opening-forming surface 25 by adhesive or the like. In other embodiments, the seal member 470 may be made of rubber or elastomer.

[0028] The nozzle cover 460 is provided to cover the outer peripheral side surface of the nozzle tip 441 and the outer peripheral side surface of the nozzle flow path member 445. In this embodiment, a refrigerant inlet 465 and a refrigerant outlet 466 are provided on the side surface of the nozzle cover 460. A groove-shaped refrigerant flow path 467 that connects the refrigerant inlet 465 and the refrigerant outlet 466 is provided on the inner wall surface of the nozzle cover 460. A refrigerant RF is supplied to the refrigerant inlet 465. The refrigerant RF is, for example, water. The refrigerant RF introduced from the refrigerant inlet 465 to the refrigerant flow path 467 is discharged from the refrigerant outlet 466. The refrigerant RF discharged from the refrigerant outlet 466 is cooled, for example, by a chiller, and circulates to the refrigerant inlet 465. O-rings 468 seal between the nozzle cover 460 and the nozzle tip 441 and between the nozzle cover 460 and the nozzle flow path member 445. The refrigerant flow path 467 may also be referred to as a cooling unit.

[0029] As shown in FIG. 1 , the second detection unit 450 is provided in the injection cylinder 410. In this embodiment, the second detection unit 450 includes a fourth pressure sensor 451A, a fifth pressure sensor 451B, and a sixth pressure sensor 451C. The fourth pressure sensor 451A is provided in the upstream portion of the injection cylinder 410. The fifth pressure sensor 451B is provided in the midstream portion of the injection cylinder 410. The sixth pressure sensor 451C is provided in the downstream portion of the injection cylinder 410, that is, near the connection portion between the injection cylinder 410 and the nozzle 440.

[0030] Each of the pressure sensors 451A to 451C detects the pressure of the mixed material inside the injection cylinder 410. Information related to the pressure detected by each of the pressure sensors 451A to 451C is transmitted to the control unit 600. In the following description, when the pressure sensors 451A to 451C are not particularly distinguished from one another, each of the pressure sensors 451A to 451C may be simply referred to as a pressure sensor 451. The number of pressure sensors 451 provided in the injection cylinder 410 is not limited to three, and may be one, or two or more. The injection cylinder 410 does not necessarily have to be provided with the second detection unit 450. The second detection unit 450 may be simply referred to as a detection unit.

[0031] The casting mold 20 is attached to the mold clamping unit 500. The mold clamping unit 500 opens and closes the casting mold 20. In this embodiment, the mold clamping unit 500 includes a fixed platen 510, a movable platen 520, and a mold driver 530. The fixed platen 510 is fixed to the tip of tie bars (not shown). The movable platen 520 is disposed opposite the fixed platen 510 and moves while being guided by the tie bars. The fixed platen 21 is attached to the fixed platen 510, and the movable platen 22 is attached to the movable platen 520. The mold driver 530 moves the movable platen 520. In this embodiment, the mold driver 530 is configured by combining a motor, a reducer, and a ball screw. The mold driver 530 is driven under the control of the control unit 600. The casting mold 20 is opened and closed by the mold driver 530 moving the movable platen 520 and the movable platen 22.

[0032] The control unit 600 is configured by a computer equipped with one or more processors, a memory, and an input / output interface for inputting and outputting signals from and to the outside. The control unit 600 controls each part of the injection molding apparatus 10 to mold a molded product by having the processor execute programs and instructions loaded into the memory. In this embodiment, the control unit 600 executes the injection process described below in molding the molded product. Note that the control unit 600 may be configured by a combination of multiple circuits instead of a computer.

[0033] FIG. 3 is a perspective view showing the configuration of the first connecting member 330 in this embodiment. The first connecting member 330 has a first cylindrical portion 331 and a first flange portion 332. The first cylindrical portion 331 is cylindrically configured. The mixing cylinder 321 is inserted into the first cylindrical portion 331. The inner wall surface of the first cylindrical portion 331 is provided so as to fit along the outer circumferential side surface of the mixing cylinder 321. The first flange portion 332 is provided at the end of the first cylindrical portion 331. A recessed seating surface 333 is provided at the end of the first cylindrical portion 331 where the first flange portion 332 is provided. When the flow path member 310 and the mixing cylinder 321 are connected by the first connecting member 330, the tip end of the mixing cylinder 321 is inserted into the first cylindrical portion 331 from the end where the seating surface 333 is provided. The rear end of the mixing cylinder 321 is formed in a flange shape, and the rear end of the mixing cylinder 321 comes into contact with the seating surface 333. Four bolt holes 334 are formed in the first flange portion 332, and with the end of the mixing cylinder 321 in contact with the seat surface 333, the first flange portion 332 is fixed to the flow path member 310 by bolts inserted into each bolt hole 334. Note that in this embodiment, as shown in FIG. 3 , the first tubular portion 331 and the first flange portion 332 are formed as a single unit, but in other embodiments, the first flange portion 332 may be formed as a separate part from the first tubular portion 331. Furthermore, similar to the second connecting member 340 described below, the first tubular portion 331 and the first flange portion 332 may each be formed from a plurality of parts.

[0034] FIG. 4 is an exploded perspective view showing the configuration of the second connecting member 340 in this embodiment. The second connecting member 340 has a second tubular portion 341 and a second flange portion 342. The second tubular portion 341 is configured in a cylindrical shape. The mixing cylinder 321 is inserted into the second tubular portion 341. An inner wall surface 345 of the second tubular portion 341 is provided so as to fit along the outer circumferential side surface of the mixing cylinder 321. The second flange portion 342 is provided at the end of the second tubular portion 341. In this embodiment, the second connecting member 340 is made up of two parts provided symmetrically on the left and right. Four bolt holes 344A are formed in the two parts. The two parts sandwich the tip end of the mixing cylinder 321 and are fixed to each other with bolts 349 inserted into each bolt hole 344A. By fixing the two parts to each other, the second tubular portion 341 is configured in a cylindrical shape.

[0035] The inner wall surface 345 of the second cylindrical portion 341 has a recess 346 and a protrusion 347. The recess 346 is a portion of the inner wall surface 345 of the second cylindrical portion 341 that is recessed radially outward of the second cylindrical portion 341. The recess 346 is provided in an annular shape centered on the central axis of the second cylindrical portion 341. An O-ring (not shown) is fitted into the recess 346. The gap between the inner wall surface 345 of the second cylindrical portion 341 and the outer wall surface of the mixing cylinder 321 is sealed by the O-ring.

[0036] The protrusion 347 is a portion of the inner wall surface 345 of the second cylindrical portion 341 that protrudes radially inward of the second cylindrical portion 341. The protrusion 347 is provided in an annular shape centered on the central axis of the second cylindrical portion 341. The protrusion 347 comes into close contact with the outer wall surface of the mixing cylinder 321 and fixes the mixing cylinder 321 by friction. The gap between the inner wall surface 345 of the second cylindrical portion 341 and the outer wall surface of the mixing cylinder 321 is sealed not only by an O-ring but also by the protrusion 347. The second flange portion 342 is provided with four bolt holes 344B, and with the mixing cylinder 321 fixed to the second cylindrical portion 341, the second flange portion 342 is fixed to the injection cylinder 410 by bolts inserted into each bolt hole 344B.

[0037] Fig. 5 is a graph showing the change in pressure P1 measured by first pressure sensor 351A. Fig. 6 is a graph showing the change in pressure P3 measured by third pressure sensor 351C. In Fig. 5 and Fig. 6, the horizontal axis represents time, and the vertical axis represents pressure.

[0038] 5 shows the transition of pressure P1 at the upstream portion of the mixing cylinder 321 measured by the first pressure sensor 351A. Because the first liquid and the second liquid are not sufficiently mixed at the upstream portion of the mixing cylinder 321, the proportion of the first liquid in the mixed material flowing over the first pressure sensor 351A fluctuates. Therefore, the waveform of pressure P1 measured by the first pressure sensor 351A becomes sinusoidal. In this embodiment, the greater the proportion of the first liquid in the mixed material, the higher the viscosity of the mixed material, and therefore the greater the proportion of the first liquid in the mixed material, the higher the pressure of the mixed material.

[0039] 6 shows the transition of pressure P3 at the downstream portion of the mixing cylinder 321 measured by the third pressure sensor 351C. Because the first and second liquids are sufficiently mixed at the downstream portion of the mixing cylinder 321, the proportion of the first liquid in the mixed material flowing over the third pressure sensor 351C is approximately constant. Therefore, the amplitude of pressure P3 measured by the third pressure sensor 351C provided at the downstream portion of the mixing cylinder 321 is smaller than the amplitude of pressure P2 measured by the first pressure sensor 351A provided at the upstream portion of the mixing cylinder 321. In this embodiment, pressure P3 measured by the third pressure sensor 351C provided at the downstream portion of the mixing cylinder 321 is approximately constant.

[0040] Fig. 7 is a first graph showing the transitions of pressures P4 to P6 measured by each pressure sensor 451A provided on the injection cylinder 410. Fig. 8 is a second graph showing the transitions of pressures P4 to P6 measured by each pressure sensor 451A provided on the injection cylinder 410. In Figs. 7 and 8, the horizontal axis represents time and the vertical axis represents pressure. In Figs. 7 and 8, the pressure P4 measured by the fourth pressure sensor 451A is represented by a solid line, the pressure P5 measured by the fifth pressure sensor 451B is represented by a dashed line, and the pressure P6 measured by the sixth pressure sensor 451C is represented by a dashed line.

[0041] 7, when the first and second liquids are sufficiently mixed by the static mixer 320, the pressures P4 to P6 measured by the pressure sensors 451A to 451C provided on the injection cylinder 410 increase over time and converge to a predetermined value. In contrast, as shown in FIG. 8, if, for example, the stirring member 325 of the static mixer 320 is damaged and the mixing of the first and second liquids by the static mixer 320 becomes insufficient, the pressures P4 to P6 measured by the pressure sensors 451A to 451C increase over time, but continue to fluctuate without converging even after a predetermined time has passed.

[0042] 9 is a flowchart showing the contents of the injection process in this embodiment. This process is started by the control unit 600 when a predetermined start command is supplied to the control unit 600. The predetermined start command is supplied to the control unit 600 when, for example, a start button (not shown) provided on the injection molding apparatus 10 is pressed.

[0043] First, in step S110, the control unit 600 drives the first pump 110 to start supplying the first liquid from the first pump 110 to the static mixer 320, and drives the second pump 210 to start supplying the second liquid from the second pump 210 to the static mixer 320.

[0044] Next, in step S120, the control unit 600 measures the pressure of the mixed material in the mixing cylinder 321 using the pressure sensors 351A to 351C of the first detection unit 350, and measures the pressure of the mixed material in the injection cylinder 410 using the pressure sensors 451A to 451C of the second detection unit 450.

[0045] In step S130, the control unit 600 determines whether the mixture ratio of the first liquid to the second liquid in the mixed material is normal. In this embodiment, the control unit 600 determines whether the mixture ratio of the first liquid to the second liquid in the mixed material is normal based on the pressure of the mixed material measured by each of the pressure sensors 351A-351C of the first detection unit 350. More specifically, if all of the pressures measured by each of the pressure sensors 351A-351C of the first detection unit 350 are equal to or lower than a predetermined upper limit and equal to or higher than a predetermined lower limit, the control unit 600 determines that the mixture ratio of the first liquid to the second liquid in the mixed material is normal. On the other hand, if at least one of the pressures measured by each of the pressure sensors 351A-351C of the first detection unit 350 is not equal to or lower than a predetermined upper limit or is not equal to or higher than a predetermined lower limit, the control unit 600 determines that the mixture ratio of the first liquid to the second liquid in the mixed material is abnormal. The predetermined upper limit value and the predetermined lower limit value are set, for example, by a test performed in advance.

[0046] If it is determined in step S130 that the mixing ratio of the first liquid to the second liquid in the mixed material is normal, the control unit 600 proceeds to step S140. On the other hand, if it is not determined in step S130 that the mixing ratio of the first liquid to the second liquid in the mixed material is normal, the control unit 600 proceeds to step S135, adjusting at least one of the amount of the first liquid supplied from the first pump 110 to the static mixer 320 and the amount of the second liquid supplied from the second pump 210 to the static mixer 320, and then proceeds to step S140.

[0047] In this embodiment, as described above, the greater the proportion of the first liquid in the mixed material, the higher the viscosity of the mixed material and the higher the pressure measured by the pressure sensor 351. Therefore, in this embodiment, if at least one of the pressures detected by the pressure sensors 351A to 351C of the first detection unit 350 exceeds a predetermined upper limit, that is, if the proportion of the first liquid in the mixed material is higher than the desired proportion, the control unit 600 reduces the output of the first pump 110 to reduce the amount of the first liquid supplied from the first pump 110 to the static mixer 320 in step S135. Note that in other embodiments, the control unit 600 may increase the output of the second pump 210 to increase the amount of the second liquid supplied from the second pump 210 to the static mixer 320 without reducing the amount of the first liquid supplied from the first pump 110 to the static mixer 320. The control unit 600 may decrease the amount of the first liquid supplied from the first pump 110 to the static mixer 320 and increase the amount of the second liquid supplied from the second pump 210 to the static mixer 320 .

[0048] On the other hand, if at least one of the pressures measured by the pressure sensors 351A to 351C of the first detection unit 350 is below a predetermined lower limit, that is, if the proportion of the first liquid in the mixed material is lower than the desired proportion, the control unit 600 reduces the output of the second pump 210 to reduce the amount of the second liquid supplied from the second pump 210 to the static mixer 320 in step S135. Note that in another embodiment, the control unit 600 may increase the amount of the first liquid supplied from the first pump 110 to the static mixer 320 by increasing the output of the first pump 110 without reducing the amount of the second liquid supplied from the second pump 210 to the static mixer 320. The control unit 600 may reduce the amount of the second liquid supplied from the second pump 210 to the static mixer 320 and increase the amount of the first liquid supplied from the first pump 110 to the static mixer 320.

[0049] In step S140, the control unit 600 determines whether the mixture state of the first liquid and the second liquid is normal. When the mixture state of the first liquid and the second liquid is normal, that is, when the first liquid and the second liquid are sufficiently mixed, the amplitude of the pressure measured by the pressure sensors 351A to 351C of the first detection unit 350 decreases from the upstream to the downstream of the static mixer 320. However, for example, when the agitation member 325 of the static mixer 320 is damaged, the first liquid and the second liquid are not sufficiently mixed, and the difference in the amplitude of the pressure measured by the pressure sensors 351A to 351C of the first detection unit 350 decreases. Therefore, in this embodiment, the control unit 600 calculates the difference between the amplitude of the first pressure sensor 351A and the amplitude of the second pressure sensor 351B, and the difference between the amplitude of the second pressure sensor 351B and the amplitude of the third pressure sensor 351C, and if the absolute value of the calculated difference is less than a predetermined value, it determines that the mixed state of the first liquid and the second liquid is normal, and if the absolute value of the calculated difference exceeds the predetermined value, it determines that the mixed state of the first liquid and the second liquid is abnormal.

[0050] Furthermore, as described above, if the mixed state of the first liquid and the second liquid is abnormal, the pressure measured by each of the pressure sensors 451A to 451C of the second detection unit 450 will fluctuate without converging to a predetermined value even after a predetermined time has passed. Therefore, in this embodiment, if the pressure measured by each of the pressure sensors 451A to 451C of the second detection unit 450 is fluctuating without converging to a predetermined value even after a predetermined time has passed, the control unit 600 determines that the mixed state of the first liquid and the second liquid is abnormal.

[0051] If it is not determined in step S140 that the mixed state of the first liquid and the second liquid is normal, control unit 600 stops first pump 110 and second pump 210 in step S143, and issues a notice that the mixed state of the first liquid and the second liquid is abnormal in step S145, and then ends this process. Control unit 600 notifies that the mixed state of the first liquid and the second liquid is abnormal, for example, by displaying a message indicating that the mixed state of the first liquid and the second liquid is abnormal on a display unit (not shown) provided in injection molding apparatus 10.

[0052] If it is determined in step S140 that the mixed state of the first and second liquids is normal, the control unit 600 determines in step S150 whether or not the metering of the mixed material has been completed. In this embodiment, as the amount of mixed material stored in the injection cylinder 410 increases, the pressure from the mixed material causes the plunger 420 to move farther away from the nozzle 440. Therefore, whether or not the metering of the mixed material has been completed is determined based on the position of the plunger 420. The position of the plunger 420 can be detected, for example, by a rotary encoder built into the motor that constitutes the plunger drive unit 430.

[0053] If it is determined in step S150 that the metering of the mixed material is complete, in step S160, control unit 600 drives plunger driver 430 to move plunger 420 toward nozzle 440, thereby injecting the mixed material from nozzle orifice 442. The mixed material injected from nozzle orifice 442 is injected into cavity Cv of casting mold 20, which has been previously clamped by mold clamping unit 500. In step S170, control unit 600 stops first pump 110 and second pump 210, and then control unit 600 terminates this process. The mixed material injected into cavity Cv is hardened by heat from heater 28 provided in casting mold 20. Here, hardening also means that the mixed material becomes hard enough to have rubber elasticity. After the mixed material injected into cavity Cv has hardened, casting mold 20 is opened by mold clamping unit 500. As the molding die 20 opens, the ejector pins 29 housed in through holes provided in the movable die 22 protrude from the movable die 22. The ejector pins 29 protruding from the movable die 22 cause the molded product made of the mixed material to be released from the movable die 22.

[0054] According to the injection molding apparatus 10 of this embodiment described above, the control unit 600 can use the pressure sensors 351A-351C of the first detection unit 350 and the pressure sensors 451A-451C of the second detection unit 450 to detect the state inside the mixing cylinder 321 into which the first and second liquids flow. More specifically, the control unit 600 can use the pressure sensors 351A-351C of the first detection unit 350 to detect an abnormality in the mixing ratio of the first and second liquids in the mixed material, and can use the pressure sensors 351A-351C of the first detection unit 350 and the pressure sensors 451A-451C of the second detection unit 450 to detect an abnormality in the mixing state of the first and second liquids in the mixed material. This makes it possible to detect and address deterioration in the quality of molded products before it occurs. In particular, in this embodiment, when the mixing ratio of the first liquid to the second liquid in the mixed material is not normal, the control unit 600 adjusts at least one of the amount of the first liquid supplied from the first pump 110 to the mixing cylinder 321 and the amount of the second liquid supplied from the second pump 210 to the mixing cylinder 321 so that the mixing ratio of the first liquid to the second liquid in the mixed material becomes normal, thereby preventing a decrease in the quality of the molded product due to an abnormality in the mixing ratio of the first liquid to the second liquid in the mixed material.

[0055] In this embodiment, the first detection unit 350 includes three pressure sensors 351A to 351C provided in the mixing cylinder 321. Therefore, the state inside the mixing cylinder 321 can be detected in more detail than in a configuration in which the state inside the mixing cylinder 321 is detected by one or two pressure sensors 351.

[0056] Furthermore, in this embodiment, the mixing section 300 includes a static mixer 320. The static mixer 320 can effectively mix the first liquid and the second liquid without rotating the stirring member 325 disposed in the mixing cylinder 321 by a motor or the like. Therefore, the energy consumed for mixing the first liquid and the second liquid can be reduced compared to a configuration in which the first liquid and the second liquid are mixed by rotating the stirring member 325 by a motor or the like.

[0057] In this embodiment, the mixing cylinder 321 is connected to the flow path member 310 via a first connecting member 330, and the first connecting member 330 has a first cylindrical portion 331 provided along the outer circumferential side surface of the mixing cylinder 321. Therefore, the first cylindrical portion 331 can reinforce the mixing cylinder 321. In addition, for example, in a configuration in which a male thread is formed on the end of the mixing cylinder 321 and a female thread is formed on the flow path member 310, and the mixing cylinder 321 is connected to the flow path member 310 by the male and female threads, the mixing cylinder 321 may become detached from the flow path member 310 due to the pressure of the material being mixed. In contrast, in this embodiment, the flange-shaped end of the mixing cylinder 321 is supported by a seat 333 provided on the first connecting member 330, and the first flange portion 332 is fixed to the flow path member 310 by four bolts, so that the mixing cylinder 321 can be prevented from becoming detached from the flow path member 310 due to the pressure of the material being mixed.

[0058] Furthermore, in this embodiment, the mixing cylinder 321 is connected to the injection cylinder 410 via a second connecting member 340, and the second connecting member 340 has a second cylindrical portion 341 provided along the outer circumferential side surface of the mixing cylinder 321. Therefore, the mixing cylinder 321 can be reinforced by the second cylindrical portion 341. Furthermore, in this embodiment, the space between the mixing cylinder 321 and the second cylindrical portion 341 is sealed by an O-ring or a protrusion 347. Therefore, even if the mixed material leaks from the connection portion between the mixing cylinder 321 and the injection cylinder 410, the mixed material can be prevented from leaking out.

[0059] Furthermore, in this embodiment, nozzle cover 460 is provided with refrigerant flow path 467 through which a refrigerant flows, which can prevent a rise in temperature of nozzle tip 441 and nozzle flow path member 445. Therefore, hardening of the mixed material inside nozzle tip 441 and nozzle flow path member 445 can be prevented.

[0060] B. Second embodiment: 10 is a front view showing a schematic configuration of injection molding apparatus 10b according to the second embodiment. Injection molding apparatus 10b according to the second embodiment differs from the first embodiment in that first detection unit 350b includes three temperature sensors 355A-355C in addition to three pressure sensors 351A-351C. The other configurations are the same as those of the first embodiment unless otherwise specified.

[0061] The temperature sensors 355A-355C of the first detection unit 350b are provided in the mixing cylinder 321. The temperature sensors 355A-355C are arranged adjacent to the pressure sensors 351A-351C. The temperature sensors 355A-355C detect the temperature of the material being mixed in the mixing cylinder 321. Information related to the temperature detected by the temperature sensors 355A-355C is transmitted to the control unit 600. In the following description, when the temperature sensors 355A-355C are not to be particularly distinguished from one another, the temperature sensors 355A-355C may be simply referred to as temperature sensors 355. The number of temperature sensors 355 provided in the mixing cylinder 321 is not limited to three, and may be one, two, or more.

[0062] 11 is a flowchart showing the contents of the injection process in this embodiment. First, in step S210, the control unit 600 drives the first pump 110 to start supplying the first liquid from the first pump 110 to the static mixer 320, and drives the second pump 210 to start supplying the second liquid from the second pump 210 to the static mixer 320.

[0063] Next, in step S220, the control unit 600 measures the pressure of the mixed material in the mixing cylinder 321 using the pressure sensors 351A-351C of the first detection unit 350b, and measures the pressure of the mixed material in the injection cylinder 410 using the pressure sensors 451A-451C of the second detection unit 450. Furthermore, the control unit 600 measures the temperature of the mixed material in the mixing cylinder 321 using the temperature sensors 355A-355C of the first detection unit 350b.

[0064] In step S230, the control unit 600 determines whether the mixture ratio of the first liquid to the second liquid in the mixed material and the temperature of the mixed material are normal. In this embodiment, similar to step S130 in the first embodiment, the control unit 600 determines whether the mixture ratio of the first liquid to the second liquid in the mixed material is normal based on the pressure of the mixed material measured by the pressure sensors 351A-351C of the first detection unit 350b, and further determines whether the temperature of the mixed material is normal based on the temperature of the mixed material measured by the temperature sensors 355A-355C of the first detection unit 350b. If the temperature of the mixed material in the mixing cylinder 321 increases, the mixed material will begin to harden, which may affect the quality of the molded product or make it impossible to eject the mixed material from the nozzle opening 442. Therefore, in this embodiment, the control unit 600 determines that the temperature of the mixed material is normal when the temperature of the mixed material measured by each of the temperature sensors 355A to 355C is equal to or lower than a predetermined upper limit temperature, and determines that the temperature of the mixed material is abnormal when the temperature of the mixed material measured by each of the temperature sensors 355A to 355C exceeds the predetermined upper limit temperature. The upper limit temperature is set to be equal to or lower than the hardening temperature of the mixed material.

[0065] If it is determined in step S230 that the mixture ratio of the first liquid to the second liquid in the mixed material is normal and that the temperature of the mixed material is normal, the control unit 600 proceeds to step S240. On the other hand, if it is determined in step S230 that at least one of the mixture ratio of the first liquid to the second liquid in the mixed material and the temperature of the mixed material is not normal, the control unit 600 adjusts in step S235 at least one of the amount of the first liquid supplied from the first pump 110 to the static mixer 320 and the amount of the second liquid supplied from the second pump 210 to the static mixer 320, and then proceeds to step S240. The process in step S235 when it is determined in step S230 that the mixture ratio of the first liquid to the second liquid in the mixed material is not normal is the same as the process in step S135 in the first embodiment. The faster the flow rate of the mixed material in the mixing cylinder 321, the greater the amount of heat generated by shear heating of the mixed material. Therefore, if the control unit 600 determines in step S230 that the temperature of the mixed material is not normal, in step S235, it reduces the amount of the first liquid supplied from the first pump 110 to the static mixer 320 and reduces the amount of the second liquid supplied from the second pump 210 to the static mixer 320, thereby slowing down the flow rate of the mixed material in the mixing cylinder 321. The processing content from step S240 onwards is the same as the processing content from step S140 onwards in the first embodiment.

[0066] According to the injection molding apparatus 10b of this embodiment described above, the first detection unit 350b includes three temperature sensors 355A-355C in addition to the three pressure sensors 351A-351C. Therefore, the temperature of the mixed material in the mixing cylinder 321 can also be detected by the first detection unit 350b. Furthermore, in this embodiment, if the temperature of the mixed material detected by each of the temperature sensors 355A-355C exceeds a predetermined upper limit temperature, the control unit 600 reduces the amount of the first liquid supplied from the first pump 110 to the mixing cylinder 321 and the amount of the second liquid supplied from the second pump 210 to the mixing cylinder 321 to prevent the temperature of the mixed material from rising in the mixing cylinder 321. This prevents the mixed material from hardening in the mixing cylinder 321, the injection cylinder 410, or the nozzle 440 before being injected into the cavity Cv. The temperature sensor 355 may also be provided in the injection cylinder 410 instead of the mixing cylinder 321. In this case, the control unit 600 may determine whether the temperature of the mixed material is normal or not based on the temperature detected by the temperature sensor 355 provided in the injection cylinder 410. Alternatively, the temperature sensor 355 may be provided in both the mixing cylinder 321 and the injection cylinder 410. In this case, the control unit 600 may determine whether the temperature of the mixed material is normal or not based on the temperature detected by at least one of the temperature sensor 355 provided in the mixing cylinder 321 and the temperature sensor 355 provided in the injection cylinder 410.

[0067] C. Third embodiment: 12 is a cross-sectional view showing the configuration of a nozzle 440c of an injection molding apparatus 10c according to the third embodiment. In the injection molding apparatus 10c according to the third embodiment, the shape of the tip of the nozzle tip 441c is different from that of the first embodiment. Unless otherwise specified, the other configurations are the same as those of the injection molding apparatus 10 according to the first embodiment shown in FIG.

[0068] In this embodiment, the nozzle tip 441c is formed of an elastomer having rubber elasticity. A skirt portion 446 is provided at the tip of the nozzle tip 441c. The skirt portion 446 has a truncated cone-like outer shape. The inner and outer diameters of the skirt portion 446 increase in size toward the opening-forming surface 25. A protrusion 447 is provided at the end face of the skirt portion 446. The protrusion 447 protrudes toward the opening-forming surface 25. The protrusion 447 is provided in an annular shape centered on the central axis of the nozzle tip 441c. When the fixed mold 21 is attached to the fixed platen 510, the skirt portion 446 is pressed against the opening-forming surface 25 and elastically deforms along the opening-forming surface 25, so that the protrusion 447 adheres closely to the opening-forming surface 25 along its entire circumference. Note that in this embodiment, the sealing member 470 shown in FIG. 2 is not provided. The skirt portion 446 is sometimes referred to as an elastically deforming portion. It is preferable that nozzle tip 441c be made of a heat-insulating elastomer, which can prevent heat from forming in molding die 20 from being transmitted to nozzle tip 441c.

[0069] According to the injection molding apparatus 10c of the present embodiment described above, the convex portion 447 adheres closely to the opening forming surface 25, thereby preventing the mixed material from leaking between the nozzle tip 441c and the opening forming surface 25. Furthermore, the convex portion 447 of the skirt portion 446 adheres closely to the opening forming surface 25, thereby preventing the portions of the skirt portion 446 other than the convex portion 447 from sticking to the opening forming surface 25. Note that the nozzle 440 of the injection molding apparatus 10b of the second embodiment may be configured with the nozzle 440c of the present embodiment.

[0070] D. Fourth embodiment: 13 is a cross-sectional view showing the configuration of a nozzle 440d of an injection molding apparatus 10d according to the fourth embodiment. In the injection molding apparatus 10d of the fourth embodiment, the shape of the tip of the nozzle tip 441d is different from that of the first embodiment. Unless otherwise specified, the other configurations are the same as those of the injection molding apparatus 10 of the first embodiment shown in FIG.

[0071] In this embodiment, the nozzle tip 441d is made of an elastomer having rubber elasticity. A constricted portion 449 is provided on the outer peripheral side surface of the tip of the nozzle tip 441d. The outer diameter of the nozzle tip 441d is reduced at the constricted portion 449. When the fixed mold 21 is attached to the fixed platen 510, the tip of the nozzle tip 441d is pressed against the opening-forming surface 25, causing the constricted portion 449 to elastically deform, and the tip surface of the nozzle tip 441d becomes parallel to the opening-forming surface 25, so that the tip surface of the nozzle tip 441d is in close contact with the opening-forming surface 25 along its entire periphery. Note that in this embodiment, the sealing member 470 shown in FIG. 2 is not provided. The constricted portion 449 is sometimes referred to as an elastically deforming portion.

[0072] According to the injection molding apparatus 10d of the present embodiment described above, the tip surface of the nozzle tip 441d is in close contact with the opening forming surface 25, thereby preventing the mixed material from leaking from between the nozzle tip 441d and the opening forming surface 25. Furthermore, since the constricted portion 449 is provided at the tip of the nozzle tip 441d, even if the tip surface of the nozzle tip 441d comes into contact with the opening forming surface 25 while being inclined with respect to the opening forming surface 25, the tip surface of the nozzle tip 441d can be in close contact with the opening forming surface 25 while being parallel to the opening forming surface 25. Note that the nozzle 440 of the injection molding apparatus 10b of the second embodiment may be configured as the nozzle 440d of the present embodiment.

[0073] E. Other Embodiments: (E1) In injection molding apparatus 10 of the first embodiment, injection molding apparatus 10c of the third embodiment, and injection molding apparatus 10d of the fourth embodiment described above, control unit 600 detects the mixing ratio of the first liquid to the second liquid in the mixed material and the mixing state of the mixed material using first detection unit 350 and second detection unit 450. In contrast, control unit 600 of injection molding apparatuses 10, 10c, and 10d does not need to detect either the mixing ratio of the first liquid to the second liquid in the mixed material or the mixing state of the mixed material.

[0074] (E2) In the injection molding apparatus 10b of the second embodiment described above, the control unit 600 uses the first detection unit 350b and the second detection unit 450 to detect the mixing ratio of the first liquid to the second liquid in the mixed material, the mixing state of the mixed material, and the temperature of the mixed material. In contrast, in the injection molding apparatus 10b, the control unit 600 does not need to detect any one of the mixing ratio of the first liquid to the second liquid in the mixed material, the mixing state of the mixed material, and the temperature of the mixed material. Also, in the injection molding apparatus 10b, the control unit 600 does not need to detect any two of the mixing ratio of the first liquid to the second liquid in the mixed material, the mixing state of the mixed material, and the temperature of the mixed material. For example, the control unit 600 may use the temperature sensor 355 to detect the temperature of the mixed material without detecting the mixing ratio of the first liquid to the second liquid in the mixed material and the mixing state of the mixed material. In this case, the pressure sensor 351 may not be provided in the mixing cylinder 321, and the pressure sensor 451 may not be provided in the injection cylinder 410.

[0075] (E3) In the injection molding apparatus 10 of the first embodiment, the injection molding apparatus 10c of the third embodiment, and the injection molding apparatus 10d of the fourth embodiment described above, the control unit 600 adjusts the output of at least one of the first pump 110 and the second pump 210 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350. In contrast, the control unit 600 of the injection molding apparatuses 10, 10c, and 10d does not need to adjust the output of the first pump 110 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350, and does not need to adjust the output of the second pump 210 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350.

[0076] (E4) In the injection molding apparatus 10b of the second embodiment described above, the control unit 600 adjusts the output of at least one of the first pump 110 and the second pump 210 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350b and the temperature of the mixed material. In contrast, in the injection molding apparatus 10b, the control unit 600 does not have to adjust the output of the first pump 110 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350b, and does not have to adjust the output of the second pump 210 in accordance with the mixture ratio of the first liquid and the second liquid in the mixed material detected using the first detection unit 350b. In the injection molding apparatus 10b, the control unit 600 does not have to adjust the output of the first pump 110 in accordance with the temperature of the mixed material detected using the first detection unit 350b, and does not have to adjust the output of the second pump 210 in accordance with the temperature of the mixed material detected using the first detection unit 350b.

[0077] (E5) In the injection molding apparatuses 10 to 10d of the above-described embodiments, the mixing section 300 is provided with a static mixer 320 in which the agitating member 325 does not rotate relative to the mixing cylinder 321, and the static mixer 320 mixes the first and second liquids. Alternatively, instead of the static mixer 320, the mixing section 300 may be provided with a dynamic mixer in which the agitating member disposed within the mixing cylinder rotates relative to the mixing cylinder, and the first and second liquids are mixed by the rotation of the agitating member. However, if a dynamic mixer is provided in the mixing section 300, a mechanism for rotating the agitating member of the dynamic mixer is required, and therefore it is preferable to provide the mixing section 300 with a static mixer 320, which has a simpler configuration.

[0078] (E6) In the injection molding apparatuses 10 to 10d of the above-described embodiments, the mixing cylinder 321 is fixed to the flow path member 310 via the first connecting member 330. In contrast, without providing the first connecting member 330, for example, a male thread may be formed on the end of the mixing cylinder 321, and a female thread may be formed on the flow path member 310, and the mixing cylinder 321 may be fixed to the flow path member 310 by the male thread and the female thread.

[0079] (E7) In the injection molding apparatuses 10 to 10d of the above-described embodiments, the mixing cylinder 321 is fixed to the injection cylinder 410 via the second connecting member 340. In contrast, without providing the second connecting member 340, for example, a male thread may be formed on the end of the mixing cylinder 321, and a female thread may be formed on the injection cylinder 410, and the mixing cylinder 321 may be fixed to the injection cylinder 410 by the male thread and the female thread.

[0080] (E8) In the injection molding apparatuses 10 to 10d of the above-described embodiments, the nozzles 440, 440c, 440d are provided with refrigerant flow paths 467 through which refrigerant flows to cool the nozzle tips 441, 441c, 441d and the nozzle flow path members 445. However, instead of the refrigerant flow paths 467, the nozzles 440, 440c, 440d may be provided with, for example, Peltier elements that cool the nozzle tips 441, 441c, 441d and the nozzle flow path members 445.

[0081] (E9) In the injection molding apparatuses 10 to 10d of the above-described embodiments, the nozzles 440, 440c, and 440d are provided with the refrigerant flow path 467. In contrast, the nozzle 440 does not necessarily need to be provided with the refrigerant flow path 467.

[0082] F. Other Forms: The present disclosure is not limited to the above-described embodiments and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following forms. The technical features in the above embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0083] (1) According to one aspect of the present disclosure, there is provided an injection molding apparatus, the injection molding apparatus comprising: a mixing unit having a cylindrical cylinder and a stirring member disposed within the cylinder, the mixing unit using the stirring member to mix a first liquid containing a thermosetting material flowing into the cylinder with a second liquid containing a polymerization initiator that starts a polymerization reaction of the thermosetting material to produce a mixed material; an injection unit having a nozzle and injecting the mixed material from the nozzle toward a cavity defined by a fixed mold and a movable mold; and a detection unit detecting a state inside the cylinder. According to this type of injection molding device, the detector can detect the state inside the cylinder into which the first and second liquids flow, making it possible to detect and deal with any deterioration in the quality of the molded product before it occurs.

[0084] (2) In the injection molding apparatus of the above form, the detection unit may detect at least one of the following conditions within the cylinder: a mixing ratio of the first liquid and the second liquid in the mixed material; a mixing state of the first liquid and the second liquid in the mixed material; and a temperature of the mixed material. According to this type of injection molding device, at least one of the mixing ratio of the first liquid and the second liquid in the mixed material, the mixing state of the first liquid and the second liquid in the mixed material, and the temperature of the mixed material is detected, making it possible to detect and deal with any deterioration in the quality of the molded product in advance.

[0085] (3) In the injection molding apparatus of the above aspect, the detection unit may have a plurality of sensors provided in the cylinder, and may detect the condition inside the cylinder based on changes in the measurement values ​​measured by the plurality of sensors. According to the injection molding device of this configuration, the condition inside the cylinder is detected by a plurality of sensors, so the condition inside the cylinder can be detected in more detail than in a configuration in which the condition inside the cylinder is detected by a single sensor.

[0086] (4) The injection molding apparatus of the above form may include a first pump that supplies the first liquid to the cylinder, a second pump that supplies the second liquid to the cylinder, and a control unit that controls at least one of the first pump and the second pump depending on the condition inside the cylinder detected by the detection unit. According to this form of injection molding apparatus, the control unit controls the first liquid supply unit and the second liquid supply unit in accordance with the condition inside the cylinder detected by the detection unit, thereby maintaining the condition inside the cylinder at an appropriate level.

[0087] (5) In the injection molding apparatus of the above aspect, the mixing section may include a static mixer having the cylinder and the stirring member that does not rotate relative to the cylinder. This type of injection molding apparatus allows the first and second liquids to be mixed effectively by the static mixer, and also consumes less energy than an injection molding apparatus that mixes the first and second liquids by rotating a stirring member disposed inside a cylinder.

[0088] (6) The injection molding apparatus of the above form may include a flow path member having a first flow path for introducing the first liquid into the cylinder, a second flow path for introducing the second liquid into the cylinder, and a confluence flow path that connects the first flow path and the second flow path to the cylinder, and the mixing section may include a first connecting member that connects the cylinder to the flow path member, and the first connecting member may have a cylindrical first cylindrical portion into which the cylinder is inserted, and a first flange portion provided at an end of the first cylindrical portion and fixed to the flow path member. According to the injection molding apparatus of this aspect, the portion of the cylinder that is connected to the flow path member can be reinforced by the first connecting member.

[0089] (7) In the injection molding apparatus of the above form, the mixing section includes a second connecting member that connects the cylinder to the injection section, and the second connecting member has a cylindrical second cylindrical section into which the cylinder is inserted and a second flange section that is provided at the end of the second cylindrical section and fixed to the injection section, and the inner wall surface of the second cylindrical section may be provided with a convex section that is arranged in a ring shape centered on the central axis of the second cylindrical section and that contacts the outer peripheral side surface of the cylinder. According to the injection molding device of this aspect, even if the mixed material leaks from the connection between the cylinder and the injection part, the convex part provided on the inner wall surface of the second cylindrical part can prevent the mixed material from leaking to the outside.

[0090] (8) In the injection molding apparatus of the above form, the fixed mold may have an opening forming surface on which an opening communicating with the cavity is formed, and the nozzle may have an elastic deformation portion that elastically deforms along the opening forming surface by contacting the opening forming surface. According to this injection molding device, the elastic deformation portion elastically deforms along the opening-forming surface, which prevents a gap from being formed between the nozzle and the opening-forming surface, thereby preventing the mixed material from leaking from the gap between the nozzle and the opening-forming surface.

[0091] (9) In the injection molding apparatus of the above aspect, the injection section may have a cooling section that cools the nozzle. According to the injection molding device of this aspect, the nozzle can be cooled by the cooling section, so that the mixed material can be prevented from hardening inside the nozzle.

[0092] The present disclosure may be realized in various forms other than an injection molding apparatus, for example, a control method for an injection molding apparatus, or the like. [Explanation of symbols]

[0093] 10...injection molding apparatus, 20...molding mold, 21...fixed mold, 22...movable mold, 28...heater, 100...first tank, 110...first pump, 200...second tank, 210...second pump, 300...mixing section, 310...flow path member, 320...static mixer, 321...mixing cylinder, 325...agitating member, 330...first connecting member, 331...first cylindrical portion, 332...first flange portion, 340...second connecting member, 341...second cylindrical portion, 342...second 2 flange portion, 350...first detection portion, 351...pressure sensor, 355...temperature sensor, 400...injection portion, 410...injection cylinder, 420...plunger, 430...plunger drive portion, 440...nozzle, 441...nozzle tip, 445...nozzle flow path member, 446...skirt portion, 449...constriction portion, 450...second detection portion, 451...pressure sensor, 460...nozzle cover, 467...refrigerant flow path, 500...mold clamping portion, 600...control portion

Claims

1. The mixing device has a cylindrical cylinder and a stirring member disposed in the cylinder, A polymerization reaction is initiated between the first liquid containing the thermosetting material and the thermosetting material. a mixing section that mixes the first liquid and a second liquid containing an initiator by the stirring member to generate a mixed material; The nozzle is directed toward a cavity defined by the fixed mold and the movable mold. an injection unit that injects the mixed material from The cylinder has a plurality of sensors, and the plurality of sensors measure a detection unit that detects a state inside the cylinder based on a change in the measurement value; A control unit; Equipped with The detection unit detects the state inside the cylinder by detecting the first liquid and the a mixing ratio of the first liquid and the second liquid in the mixed material; a mixed state of the first liquid and the second liquid in the mixed material; and detecting at least one of the temperature of the material; The control unit controls the mixing in accordance with a difference in amplitude of the pressure measured by each of the plurality of sensors. Determine whether the connection is normal. Injection molding equipment.

2. An injection molding apparatus according to claim 1, The plurality of sensors includes at least three sensors: a first sensor, a second sensor, and a a third sensor; The first sensor, the second sensor, and the third sensor are arranged along the flow path of the mixed material. The first sensor, the second sensor, and the third sensor are arranged in this order, the difference between the amplitude of the first sensor and the amplitude of the second sensor, and the amplitude of the second sensor and the amplitude of the third sensor is calculated, and the absolute value of the calculated difference exceeds a predetermined value. If the above condition is met, it is determined that the mixed state is equal to or greater than the above condition. Injection molding equipment.

3. 3. The injection molding apparatus according to claim 1 or 2, a first pump that supplies the first liquid to the cylinder; a second pump that supplies the second liquid to the cylinder; The first pump and the second pump are connected to each other in accordance with the state inside the cylinder detected by the detection unit. a control unit that controls at least one of the first pump and the second pump; An injection molding apparatus comprising:

4. 4. The injection molding apparatus according to claim 1, The mixing section includes the cylinder and the stirring member that does not rotate relative to the cylinder. An injection molding apparatus comprising a static mixer having:

5. 5. The injection molding apparatus according to claim 1, a first flow path for introducing the first liquid into the cylinder; a second flow path that communicates the first flow path and the second flow path with the cylinder; a flow path member having a merging flow path; the mixing section includes a first connecting member that connects the cylinder to the flow path member, The first connecting member has a cylindrical first cylindrical portion into which the cylinder is inserted, and a a first flange portion provided at an end portion of the injection molding apparatus and fixed to the flow path member.

6. 6. The injection molding apparatus according to claim 1, the mixing section includes a second connecting member that connects the cylinder to the injection section; The second connecting member has a cylindrical second cylindrical portion into which the cylinder is inserted, and a second flange portion provided at an end portion and fixed to the injection portion, The inner wall surface of the second cylindrical portion is provided with an annular shape centered on the central axis of the second cylindrical portion, An injection molding device in which a convex portion is provided to contact the outer peripheral side surface of a cylinder.

7. 7. The injection molding apparatus according to claim 1, the fixed mold has an opening forming surface on which an opening communicating with the cavity is formed, The nozzle is elastically moved along the opening forming surface by contacting the opening forming surface. An injection molding apparatus having an elastically deforming portion that undergoes elastic deformation.

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