Plasticizing equipment and injection molding equipment

Abstract

To provide a plasticizer capable of reducing the amount of material discarded when exchanging materials.SOLUTION: A plasticizer includes: a passage defining part connected to a hopper that stores a material, and for defining a supply passage through which the material is supplied from the hopper; a plasticizing part having an introductory part that communicates with the supply passage, and a screw, and plasticizing the material supplied from the introductory part by the rotation of the screw to generate a molten material; and a material detection part for detecting the presence or absence of the material on the supply passage.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a plasticizing device, and injection molding equipment Place Regarding. [Background technology]

[0002] 2. Description of the Related Art There has been known a conventional injection molding apparatus in which a material plasticized by a plasticizing device is supplied to a cavity formed by a pair of molds and injected from a nozzle.

[0003] For example, Patent Document 1 describes an injection molding device that has a detection sensor placed at a predetermined position in a hopper, and after receiving a signal regarding color change conditions, if the sensor detects that the material has run out, supplies a predetermined amount of color change material to the hopper. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 4-307215 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, the detection sensor is disposed in the hopper, so that when the material is replaced, the material remaining between the hopper and the plasticizing section is discarded. [Means for solving the problem]

[0006] One aspect of the plasticizing device according to the present invention is a passage defining portion that is connected to a hopper that stores a material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the introduction section by rotation of the screw to generate a molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes.

[0007] One aspect of the injection molding apparatus according to the present invention is a plasticizer for plasticizing the material into a molten material; a nozzle for injecting the molten material supplied from the plasticizer into a mold; Including, The plasticizing device comprises: a passage defining portion that is connected to a hopper that stores the material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the supply passage by rotation of the screw to generate the molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes.

[0008] One aspect of the three-dimensional printing apparatus according to the present invention is to A three-dimensional printing apparatus for printing a three-dimensional object, comprising: a plasticizer for plasticizing the material into a molten material; a nozzle for ejecting the molten material supplied from the plasticizer toward a stage; Including, The plasticizing device comprises: a passage defining portion that is connected to a hopper that stores the material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the supply passage by rotation of the screw to generate the molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view showing a schematic diagram of an injection molding apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a cross-sectional view illustrating an injection molding apparatus according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a perspective view showing a flat screw of the injection molding apparatus according to the embodiment of the present invention. [Figure 4] FIG. 2 is a plan view illustrating a barrel of the injection molding device according to the embodiment. [Diagram 5] 1 is a cross-sectional view that illustrates a schematic diagram of an injection molding apparatus according to an embodiment of the present invention. [Figure 6] FIG. 2 is a diagram illustrating a supply pipe of the injection molding apparatus according to the embodiment. [Figure 7] FIG. 11 is a cross-sectional view illustrating an injection molding apparatus according to a modified example of the embodiment. [Figure 8] FIG. 1 is a cross-sectional view illustrating a three-dimensional modeling apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are necessarily essential components of the present invention.

[0011] 1. Injection molding equipment 1.1. Overall structure First, an injection molding apparatus according to this embodiment will be described with reference to the drawings. Fig. 1 is a side view showing a schematic diagram of an injection molding apparatus 100 according to this embodiment. In Fig. 1, an X-axis, a Y-axis, and a Z-axis are shown as three mutually orthogonal axes. The X-axis direction and the Y-axis direction are, for example, horizontal directions. The Z-axis direction is, for example, vertical directions.

[0012] As shown in FIG. 1, the injection molding apparatus 100 includes a hopper 10, an injection section 20, a mold section 30, and a mold clamping section 40.

[0013] The hopper 10 stores the material in the injection section 20. The material in pellet form or powder form is stored in the hopper 10. An example of the material stored in the hopper 10 is ABS (Acrylonitrile Butadiene Styrene) resin in pellet form.

[0014] The injection section 20 plasticizes the material supplied from the hopper 10 to form a molten material. Then, the injection section 20 injects the molten material toward the mold section 30.

[0015] Plasticization is a concept that includes melting, and refers to changing a material from a solid to a fluid state. Specifically, for materials that undergo glass transition, plasticization refers to raising the temperature of the material above the glass transition point. For materials that do not undergo glass transition, plasticization refers to raising the temperature of the material above the melting point.

[0016] A cavity corresponding to the shape of the molded product is formed in the mold section 30. The molten material injected from the injection section 20 flows into the cavity. The molten material is then cooled and solidified to produce the molded product.

[0017] The mold clamping unit 40 opens and closes the mold section 30. After the molten material has cooled and solidified, the mold clamping unit 40 opens the mold section 30. As a result, the molded product is ejected to the outside.

[0018] 1.2. Specific configuration Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1, which is a schematic diagram of the injection molding apparatus 100. Fig. 2 illustrates an injection section 20, a mold section 30, and a mold clamping section 40. As shown in Fig. 2, the injection section 20 has, for example, a plasticizing device 60 including a control section 50 and a plasticizing section 61, an injection control section 70, and a nozzle 80.

[0019] The control unit 50 is configured, for example, by a computer having a processor, a main storage device, and an input / output interface for inputting and outputting signals from and to the outside. The control unit 50 performs various functions, for example, by the processor executing a program loaded into the main storage device. Specifically, the control unit 50 controls the mold clamping unit 40 and the plasticizing unit 61. Note that the control unit 50 may be configured by a combination of multiple circuits instead of a computer.

[0020] The plasticizing unit 61 plasticizes the material supplied from the hopper 10 to generate a pasty molten material having fluidity, and guides the molten material to the injection control unit 70. The plasticizing unit 61 has, for example, a screw case 62, a drive motor 64, a flat screw 110, a barrel 120, a heating unit 130, and a check valve 140.

[0021] The screw case 62 is a housing that houses the flat screw 110. The flat screw 110 is housed in a space surrounded by the screw case 62 and the barrel 120.

[0022] The drive motor 64 is provided on the upper surface of the screw case 62. The drive motor 64 rotates the flat screw 110. The drive motor 64 is controlled by the control unit 50.

[0023] The flat screw 110 has a generally cylindrical shape whose size in the direction of the rotation axis RA is smaller than the size in the direction perpendicular to the direction of the rotation axis RA. In the illustrated example, the rotation axis RA is parallel to the Y axis. The flat screw 110 rotates about the rotation axis RA by the torque generated by the drive motor 64. The plasticizing section 61 plasticizes the material supplied from the hopper 10 by the rotation of the flat screw 110. The flat screw 110 has an upper surface 111, a groove forming surface 112 opposite to the upper surface 111, and a side surface 113 connecting the upper surface 111 and the groove forming surface 112. Here, FIG. 3 is a perspective view showing the flat screw 110 in a schematic manner. For convenience, FIG. 3 shows a state in which the vertical positional relationship is reversed from the state shown in FIG. 2. Also, FIG. 2 shows the flat screw 110 in a simplified form.

[0024] As shown in FIG. 3, the first groove 114 is provided on the groove forming surface 112 of the flat screw 110. The first groove 114 has, for example, a central portion 115, a groove connecting portion 116, and a material introduction portion 117. The central portion 115 faces a communication hole 126 provided in the barrel 120. The central portion 115 communicates with the communication hole 126. The groove connecting portion 116 connects the central portion 115 and the material introduction portion 117. In the illustrated example, the groove connecting portion 116 is provided in a spiral shape from the central portion 115 toward the outer periphery of the groove forming surface 112. The material introduction portion 117 is provided on the outer periphery of the groove forming surface 112. That is, the material introduction portion 117 is provided on the side surface 113 of the flat screw 110. The material supplied from the hopper 10 is introduced into the first groove 114 from the material introduction section 117, and is transported through the groove connection section 116 and the central section 115 to the communication hole 126 provided in the barrel 120. The number of the first grooves 114 is not particularly limited, and two or more first grooves 114 may be provided.

[0025] As shown in Fig. 2, the barrel 120 is provided below the flat screw 110. The barrel 120 has an opposing surface 122 that faces the groove forming surface 112 of the flat screw 110. A communication hole 126 is provided at the center of the opposing surface 122. Here, Fig. 4 is a plan view that shows a schematic view of the barrel 120. For convenience, the barrel 120 is shown in a simplified form in Fig. 2.

[0026] As shown in FIG. 4, the opposing surface 122 of the barrel 120 is provided with a second groove 124 and a communication hole 126. A plurality of second grooves 124 are provided. In the illustrated example, six second grooves 124 are provided, but the number is not particularly limited. The plurality of second grooves 124 are provided around the communication hole 126 when viewed from the Y-axis direction. One end of the second groove 124 is connected to the communication hole 126, and the second groove 124 extends in a spiral shape from the communication hole 126 toward the outer periphery of the opposing surface 122. The second groove 124 has a function of guiding the molten material to the communication hole 126.

[0027] The shape of the second groove 124 is not particularly limited, and may be, for example, linear. The second groove 124 does not have to be provided on the opposing surface 122. However, in order to effectively guide the molten material to the communication hole 126, it is preferable that the second groove 124 be provided on the opposing surface 122.

[0028] The heating section 130 heats the material supplied between the flat screw 110 and the barrel 120. The heating section 130 is provided in, for example, the barrel 120. In the illustrated example, the heating section 130 is composed of four heaters provided in the barrel 120. The output of the heating section 130 is controlled by the control section 50. The plasticizing section 61 heats the material while transporting it toward the communication hole 126 by the flat screw 110, the barrel 120, and the heating section 130 to generate a molten material, and causes the generated molten material to flow out from the communication hole 126 to the injection control section 70.

[0029] 2, the check valve 140 is provided in the communication hole 126. The check valve 140 prevents the molten material from flowing back from the communication hole 126 to the first groove 114 provided in the flat screw 110.

[0030] The injection control unit 70 has, for example, a cylinder 72, a plunger 74, and a plunger driving unit 76. The cylinder 72 is a substantially cylindrical member connected to the communication hole 126. The plunger 74 moves inside the cylinder 72. The plunger 74 is driven by the plunger driving unit 76 which is composed of a motor, gears, etc. The plunger driving unit 76 is controlled by the control unit 50.

[0031] The injection control unit 70 performs a metering operation and an injection operation by sliding the plunger 74 inside the cylinder 72. The metering operation refers to an operation of guiding the molten material located in the communication hole 126 into the cylinder 72 by moving the plunger 74 in the -X axis direction away from the communication hole 126, and measuring it inside the cylinder 72. The injection operation refers to an operation of injecting the molten material in the cylinder 72 into the mold section 30 through the nozzle 80 by moving the plunger 74 in the +X axis direction approaching the communication hole 126.

[0032] The nozzle 80 is provided with a nozzle hole 82 that communicates with the communication hole 126. The nozzle hole 82 injects the molten material supplied from the plasticizing section 61 into the molding die 32 of the mold section 30. Specifically, by performing the above-mentioned measuring operation and injection operation, the molten material measured in the cylinder 72 is sent from the injection control section 70 to the nozzle hole 82 via the communication hole 126. The molten material is then injected from the nozzle hole 82 into the mold section 30.

[0033] The mold section 30 has a molding die 32. The molding die 32 is a metal mold. The molten material sent to the nozzle hole 82 is injected from the nozzle hole 82 into a cavity 34 of the molding die 32. Specifically, the molding die 32 has a movable die 36 and a fixed die 38 facing each other, and has a cavity 34 between the movable die 36 and the fixed die 38. The cavity 34 is a space corresponding to the shape of the molded product. The movable die 36 and the fixed die 38 are made of metal. The movable die 36 and the fixed die 38 may also be made of ceramic or resin.

[0034] The mold clamping unit 40 has, for example, a mold driving unit 42 and a ball screw unit 44. The mold driving unit 42 is composed of, for example, a motor, gears, etc. The mold driving unit 42 is connected to the movable mold 36 via the ball screw unit 44. The driving of the mold driving unit 42 is controlled by the control unit 50. The ball screw unit 44 transmits the power generated by the driving of the mold driving unit 42 to the movable mold 36. The mold clamping unit 40 opens and closes the mold unit 30 by moving the movable mold 36 by the mold driving unit 42 and the ball screw unit 44.

[0035] 1.3. Path definition and material detection section Fig. 5 is a cross-sectional view showing a schematic diagram of the injection molding apparatus 100, and is a cross-sectional view of the injection molding apparatus 100 shown in Fig. 1 cut along a plane parallel to a YZ plane including the Y axis and the Z axis. As shown in Fig. 5, the plasticizing apparatus 60 includes a passage defining section 150, a cooling section 160, and a material detecting section 170. For convenience, the plasticizing apparatus 60 is illustrated in a simplified form in Fig. 5.

[0036] The passage defining portion 150 is connected to the hopper 10 that stores the material via a hopper connecting pipe 16. In the illustrated example, the hopper 10 is composed of a tapered portion 12 that gradually increases in size in the Y-axis direction toward the +Z-axis direction, and a constant width portion 14 that is connected to the tapered portion 12 and has a constant size in the Y-axis direction. The constant width portion 14 has an outlet 15 that sends the material in the hopper 10 to the hopper connecting pipe 16. The passage defining portion 150 may be provided integrally with the hopper connecting pipe 16.

[0037] The passage defining portion 150 connects the hopper 10 and the plasticizing portion 61 via the hopper connecting pipe 16. The passage defining portion 150 defines a supply passage 152 to which the material is supplied from the hopper 10. In the illustrated example, the size of the supply passage 152 in the Y-axis direction is the same as the size of the hollow portion 17 of the hopper connecting pipe 16 in the Y-axis direction. The size of the passage defining portion 150 in the Y-axis direction is larger than the size of the hopper connecting pipe 16 in the Y-axis direction. The passage defining portion 150 may be provided integrally with the screw case 62. In this case, it can be said that the supply passage 152 is provided in the screw case 62, and the passage defining portion 150 is the screw case 62.

[0038] The supply passage 152 communicates with the material introduction section 117 of the first groove 114 provided in the flat screw 110 of the plasticizing section 61. The supply passage 152 communicates with the communication hole 126 provided in the barrel 120 via the first groove 114. The material stored in the hopper 10 is supplied to the first groove 114 through the supply passage 152.

[0039] The passage defining portion 150 supports the material detecting portion 170. Here, Fig. 6 is a schematic diagram of the passage defining portion 150. As shown in Figs. 5 and 6, the passage defining portion 150 is provided with, for example, a communication hole 154 that communicates with the supply passage 152. The material detecting portion 170 is inserted into the communication hole 154 and fixed to the passage defining portion 150.

[0040] The cooling section 160 is provided in the passage defining section 150. As described above, the passage defining section 150 may be provided integrally with the screw case 62. In this case, it can be said that the cooling section 160 is provided in the screw case 62. The cooling section 160 cools the outer periphery of at least one of the flat screw 110 and the barrel 120. In other words, the cooling section 160 may cool both the flat screw 110 and the barrel 120, or may cool only one of the flat screw 110 and the barrel 120.

[0041] 6, the cooling unit 160 is provided to surround the supply passage 152 while avoiding the material detection unit 170. This reduces the possibility that the material detection unit 170 will break down due to the heat of the heating unit 130. The cooling unit 160 is, for example, a cooling pipe through which a refrigerant such as water flows. The cooling unit 160 is connected, for example, via a cooling pipe (not shown), to a circulating device for feeding the refrigerant and a cooling device for cooling the refrigerant.

[0042] The cooling section 160 and the heating section 130 form a temperature gradient in which the temperature increases from the outer periphery of the barrel 120 toward the communicating hole 126. This temperature gradient allows the material to be efficiently supplied from the material introduction section 117 to the central section 115 of the flat screw 110. For example, if the temperature of the outer periphery of the barrel is too high, the material may melt when it is introduced into the material introduction section, causing the material to leak to the outside.

[0043] The material detection unit 170 is supported by the passage definition unit 150 as shown in FIG. 5. The shortest distance D1 between the material detection unit 170 and the material introduction unit 117 of the first groove 114 is smaller than the shortest distance D2 between the material detection unit 170 and the outlet 15 of the hopper 10. The tip 172 of the material detection unit 170 is exposed to the supply passage 152. As shown in FIG. 6, the supply passage 152 is located between the material detection unit 170 and the cooling unit 160. As shown in FIG. 5, when viewed from the cross section, the material detection unit 170, the supply passage 152, and the cooling unit 160 are arranged in this order from the top. In the illustrated example, the "cross section" is a cross section when the plasticizing device 60 is cut by a plane parallel to the YZ plane, and the material detection unit 170, the supply passage 152, and the cooling unit 160 are arranged in this order in the +Y axis direction. The +Y axis direction is, for example, the direction in which the molten material is discharged.

[0044] As shown in Fig. 5, the material detection unit 170 is provided closer to the cooling unit 160 than the heating unit 130. That is, the shortest distance D3 between the material detection unit 170 and the cooling unit 160 shown in Fig. 6 is smaller than the shortest distance D4 between the material detection unit 170 and the heating unit 130 shown in Fig. 5. As viewed from the Y-axis direction, the heating unit 130, the cooling unit 160, and the material detection unit 170 are provided in this order from the center C of the barrel 120 toward the outside. In the example shown in Fig. 5, the cooling unit 160 is located in the +Z-axis direction from the heating unit 130, and the material detection unit 170 is located in the +Z-axis direction from the cooling unit 160.

[0045] The material detection unit 170 detects the presence or absence of material in the supply passage 152. The material detection unit 170 is, for example, a proximity sensor such as a high-frequency induction type proximity sensor or a capacitance type proximity sensor.

[0046] When the material detection unit 170 detects that the material is out of stock, the control unit 50 receives a signal from the material detection unit 170, and after a set purge time has elapsed, controls the flat screw 110 via the drive motor 64 to stop the rotation of the flat screw 110. Furthermore, when the material detection unit 170 detects that the material is out of stock, the control unit 50 receives a signal from the material detection unit 170, and after a set purge time has elapsed, controls the plunger drive unit 76 and the mold drive unit 42 to stop the drive of the plunger 74 and the movement of the movable mold 36. The purge time is a time for discharging the material remaining in the first groove 114 provided in the flat screw 110 and the material remaining in the communication hole 126 provided in the barrel 120 when replacing the material.

[0047] Even if the material detection unit 170 detects that the material is out of stock, the control unit 50 does not stop the operation of the heating unit 130. If the operation of the heating unit 130 is stopped when the material detection unit 170 detects that the material is out of stock, the material may harden, for example, in the communication hole 126 provided in the barrel 120, and it will take a long time to return to normal.

[0048] 1.4. Effects The plasticizing device 60 includes a passageway defining section 150 that is connected to a hopper 10 that stores material and defines a supply passageway 152 through which the material is supplied from the hopper 10, a material introduction section 117 that communicates with the supply passageway 152, a plasticizing section 61 that has a flat screw 110 and plasticizes the material supplied from the material introduction section 117 by the rotation of the flat screw 110 to generate a molten material, and a material detection section 170 that detects the presence or absence of material in the supply passageway 152. Therefore, the amount of material remaining in the supply passageway 152 can be reduced when replacing the material, compared to when the material detection section detects the presence or absence of material in the hopper. Therefore, the amount of material that is discarded can be reduced. Furthermore, in the plasticizing device 60, the material detection section 170 is provided in the passageway defining section 150, so that the structure of the plasticizing section 61 can be simplified.

[0049] The plasticizer 60 includes a control unit 50, which stops the rotation of the flat screw 110 when the material detector 170 detects that the material is out of stock. Therefore, the plasticizer 60 can prevent defects caused by short shots and damage to the device caused by idling.

[0050] In the plasticizing device 60, the flat screw 110 has a groove forming surface 112 on which a first groove 114 is formed, and the plasticizing section 61 has an opposing surface 122 facing the groove forming surface 112, and a barrel 120 on which a communication hole 126 is formed in the opposing surface 122. Therefore, in the plasticizing device 60, material can be supplied from the supply passage 152 to the first groove 114.

[0051] In the plasticizing device 60, the plasticizing section 61 has a heating section 130 that heats the material supplied between the flat screw 110 and the barrel 120, and a cooling section 160 that cools the outer periphery of at least one of the flat screw 110 and the barrel 120, and the material detection section 170 is provided closer to the cooling section 160 than to the heating section 130. Therefore, in the plasticizing device 60, the possibility that the material detection section 170 will break down due to the heat of the heating section 130 can be reduced compared to a case in which the material detection section is provided closer to the heating section than to the cooling section.

[0052] In the plasticizing device 60, the passage defining section 150 may be the screw case 62 that houses the flat screw 110, the heating section 130 is provided in the barrel 120, the cooling section 160 is provided in the screw case 62, and when viewed from the cross section, the material detection section 170, the supply passage 152, and the cooling section 160 are arranged in this order from the top. Therefore, in the plasticizing device 60, the possibility that the material in the supply passage 152 will melt due to the heat of the heating section 130 can be reduced compared to a case in which the material detection section, the supply passage, and the cooling section are not arranged in this order. If the material in the supply passage melts, the material cannot be efficiently guided to the communication hole provided in the barrel.

[0053] In the plasticizing device 60, the heating section 130, the cooling section 160, and the material detection section 170 are provided in this order from the center C of the barrel 120 toward the outside when viewed from a direction perpendicular to the groove forming surface 112. Therefore, in the plasticizing device 60, it is possible to reduce the possibility that the material detection section 170 will break down due to the heat of the heating section 130. In the illustrated example, the direction perpendicular to the groove forming surface 112 is the Y-axis direction.

[0054] In the plasticizer 60, the shortest distance D1 between the material detector 170 and the material feed section 117 is smaller than the shortest distance D2 between the material detector 170 and the outlet 15 of the hopper 10. Therefore, in the plasticizer 60, the amount of material present in the supply passage 152 when the material detector 170 detects that the material is out of material can be reduced compared to when the distance D1 is greater than the distance D2.

[0055] The material detection unit 170 may be a weight sensor or a pressure sensor, and may detect the presence or absence of material by quantifying the remaining amount. In this case, the control unit 50 may display the quantified information on a display unit (not shown). The quantified information is not particularly limited, but may be, for example, "3 hours until production stops."

[0056] In addition, in the above example, a flat screw 110 whose size in the direction of the rotation axis RA is smaller than its size in the direction perpendicular to the direction of the rotation axis RA is used as the screw, but instead of the flat screw 110, a rod-shaped in-line screw that is long in the direction of the rotation axis RA may be used.

[0057] 2. Modifications of injection molding equipment 2.1. First variant Next, an injection molding apparatus according to a first modified example of this embodiment will be described with reference to the drawings. Fig. 7 is a side view that shows a schematic diagram of an injection molding apparatus 200 according to a first modified example of this embodiment.

[0058] Hereinafter, in the injection molding apparatus 200 according to the first modified example of this embodiment, components having the same functions as the components of the injection molding apparatus 100 according to the present embodiment described above will be given the same reference numerals, and detailed description thereof will be omitted.

[0059] As shown in FIG. 7, the injection molding apparatus 200 differs from the above-described injection molding apparatus 100 in that the plasticizing apparatus 60 includes a supplying apparatus 210 .

[0060] In the injection molding apparatus 200, when the material detection unit 170 detects that the material is out of stock, the control unit 50 receives a signal from the material detection unit 170, and after a set purge time has elapsed, controls the supply device 210 to supply material to the hopper 10. In this way, in the injection molding apparatus 200, when the material detection unit 170 detects that the material is out of stock, the supply device 210 automatically supplies material to the hopper 10, thereby eliminating the need to supply material to the hopper 10.

[0061] 2.2. Second variant Next, an injection molding apparatus according to a second modified example of this embodiment will be described. In the above-described injection molding apparatus 100, ABS pellets are used as the material for forming the molded product.

[0062] In contrast, in the injection molding apparatus according to the second modified example of this embodiment, the material used in the plasticizing section 61 can be, for example, a material having thermoplasticity other than ABS, a metal material, a ceramic material, or other various materials as the main material. Here, the "main material" refers to a material that is the core material forming the shape of the molded product, and refers to a material that occupies 50% by weight or more in the molded product. The above-mentioned materials include those main materials that are melted alone, and those in which some components contained together with the main material are melted and turned into a paste.

[0063] Examples of the thermoplastic material include thermoplastic resins, such as general-purpose engineering plastics such as polypropylene (PP), polyethylene (PE), polyacetal (POM), polyvinyl chloride (PVC), polyamide (PA), acrylonitrile-butadiene-styrene (ABS), polylactic acid (PLA), polyphenylene sulfide (PPS), polycarbonate (PC), modified polyphenylene ether, polybutylene terephthalate, and polyethylene terephthalate, and engineering plastics such as polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, polyimide, polyamideimide, polyetherimide, and polyetheretherketone (PEEK).

[0064] The thermoplastic material may contain additives such as pigments, metals, ceramics, and wax, flame retardants, antioxidants, and heat stabilizers. The thermoplastic material is plasticized and converted to a molten state in the plasticizing section 61 by the rotation of the flat screw 110 and the heating of the heating section 130. The molten material thus generated is discharged from the nozzle 80 and then hardened by a decrease in temperature.

[0065] It is desirable that the thermoplastic material be heated to or above its glass transition point and in a completely molten state before being discharged from the nozzle 80. For example, ABS has a glass transition point of about 120° C., and it is desirable that the temperature of ABS is about 200° C. when it is discharged from the nozzle 80.

[0066] In the plasticizing section 61, for example, a metal material may be used as the main material instead of the above-mentioned material having thermoplasticity. In this case, it is preferable that a component that melts when the molten material is generated is mixed with a powder material made by powdering the metal material, and the powder material is introduced into the plasticizing section 61.

[0067] Examples of metal materials include single metals such as magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr), aluminum (Al), titanium (Ti), copper (Cu), and nickel (Ni), or alloys containing one or more of these metals, as well as maraging steel, stainless steel, cobalt-chromium-molybdenum, titanium alloys, nickel alloys, aluminum alloys, cobalt alloys, and cobalt-chromium alloys.

[0068] Instead of the above-mentioned metal materials, a ceramic material can be used as the main material for the plasticized portion 61. Examples of the ceramic material include oxide ceramics such as silicon dioxide, titanium dioxide, aluminum oxide, and zirconium oxide, and non-oxide ceramics such as aluminum nitride.

[0069] The powder material of the metallic material or the ceramic material fed into the hopper 10 may be a mixed material in which a single metal powder, an alloy powder, or a ceramic material powder are mixed together. The powder material of the metallic material or the ceramic material may be coated with, for example, the above-mentioned thermoplastic resin or a thermoplastic resin other than the above. In this case, the thermoplastic resin may be melted in the plasticizing section 61 to exhibit fluidity.

[0070] For example, a solvent may be added to the powder material of the metal material or ceramic material to be fed into the hopper 10. Examples of the solvent include water; (poly)alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; acetates such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, and isobutyl acetate; aromatic hydrocarbons such as benzene, toluene, and xylene; ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, ethyl-n-butyl ketone, diisopropyl ketone, and acetylacetone; alcohols such as ethanol, propanol, and butanol; tetraalkylammonium acetates; sulfoxide-based solvents such as dimethyl sulfoxide and diethyl sulfoxide; pyridine-based solvents such as pyridine, γ-picoline, and 2,6-lutidine; tetraalkylammonium acetates (e.g., tetrabutylammonium acetate, etc.); and ionic liquids such as butyl carbitol acetate.

[0071] Additionally, for example, a binder may be added to the powder material of the metal material or ceramic material fed into the hopper 10. Examples of the binder include acrylic resin, epoxy resin, silicone resin, cellulose-based resin, other synthetic resins, PLA (polylactic acid), PA (polyamide), PPS (polyphenylene sulfide), PEEK (polyether ether ketone), and other thermoplastic resins.

[0072] 3. Three-dimensional printing equipment Next, the three-dimensional modeling apparatus according to this embodiment will be described with reference to the drawings. Fig. 8 is a side view that shows a schematic diagram of the three-dimensional modeling apparatus 300 according to this embodiment.

[0073] 8, the three-dimensional modeling apparatus 300 includes, for example, a hopper 10, a plasticizing device 60, a nozzle 80, a stage 310, a moving mechanism 320, and a control unit 50. Although not shown, the three-dimensional modeling apparatus 300 may include the above-mentioned supply device 210.

[0074] The plasticizing device 60 includes a plasticizing section 61, a passage defining section 150, and a material detecting section 170. The plasticizing section 61 has a screw case 62, a driving motor 64, a flat screw 110, a barrel 120, a heating section 130, and a check valve 140. In the illustrated example, the passage defining section 150 is provided in the screw case 62.

[0075] The nozzle 80 ejects the molten material supplied from the plasticizer 60 toward the stage 310. Specifically, the three-dimensional modeling device 300 drives the movement mechanism 320 to change the relative position between the nozzle 80 and the stage 310 while ejecting the molten material from the nozzle 80 onto the stage 310. In this way, the three-dimensional modeling device 300 forms a three-dimensional object having a desired shape on the stage 310.

[0076] The stage 310 is moved by a moving mechanism 320. The three-dimensional object is formed on a modeling surface 312 of the stage 310.

[0077] The movement mechanism 320 changes the relative position between the nozzle 80 and the stage 310. In the illustrated example, the movement mechanism 320 moves the stage 310 relative to the nozzle 80. The movement mechanism 320 is configured, for example, by a three-axis positioner that moves the stage 310 in the X-axis direction, the Y-axis direction, and the Z-axis direction by the driving forces of three motors 322. The motors 322 are controlled by the control unit 50.

[0078] The moving mechanism 320 may be configured to move the nozzle 80 without moving the stage 310. Alternatively, the moving mechanism 320 may be configured to move both the nozzle 80 and the stage 310.

[0079] The control unit 50 controls the moving mechanism 320 and the plasticizing device 60 based on previously acquired modeling data, thereby ejecting molten material from the nozzle 80 onto a predetermined position on the stage 310, thereby forming a three-dimensional object.

[0080] The above-described embodiment and modifications are merely examples, and the present invention is not limited to these. For example, the embodiments and modifications can be appropriately combined.

[0081] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments, or configurations that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

[0082] The following can be derived from the above-described embodiment.

[0083] One embodiment of the plasticizer comprises: a passage defining portion that is connected to a hopper that stores a material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the introduction section by rotation of the screw to generate a molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes.

[0084] According to this plasticizing device, the amount of material remaining in the supply passage when replacing the material can be reduced compared to when the material detector detects the presence or absence of material in the hopper, and therefore the amount of material wasted can be reduced.

[0085] In one embodiment of the plasticizing device, A control unit is included. The control unit may control the screw to stop rotation of the screw when the material detection unit detects that the material has run out.

[0086] This plasticizing device can prevent defects caused by short shots and damage to the device due to idle running.

[0087] In one embodiment of the plasticizing device, A supply device for supplying the material to the hopper; A control unit; Including, The control unit may, when the material detection unit detects that the material is out of material, control the supply device to supply the material to the hopper.

[0088] According to this plasticizing device, when the material detection unit detects that the material is out of material, the supply device automatically supplies material to the hopper, thereby eliminating the need to supply material to the hopper.

[0089] In one embodiment of the plasticizing device, The screw has a groove forming surface on which grooves are provided, The plasticizing portion may have a barrel having a facing surface facing the groove forming surface and a communicating hole formed in the facing surface.

[0090] This plasticizing device allows material to be fed from a feed passage into the groove.

[0091] In one embodiment of the plasticizing device, The plasticizing section includes: A heating section that heats the material supplied between the screw and the barrel; a cooling section that cools an outer periphery of at least one of the screw and the barrel; having The material detection unit may be provided closer to the cooling unit than to the heating unit.

[0092] According to this plasticizing device, the possibility of the material detection unit being broken down by the heat of the heating unit can be reduced, compared to when the material detection unit is provided closer to the heating unit than to the cooling unit.

[0093] In one embodiment of the plasticizing device, the passage defining portion is a case that accommodates the screw, The heating unit is provided in the barrel, The cooling unit is provided in the case, When viewed from the cross section, the material detection section, the supply passage, and the cooling section may be arranged in this order from the top.

[0094] According to this plasticizing device, the possibility of the material in the supply passage being melted by the heat of the heating section can be reduced compared to a case where the material detection section, the supply passage, and the cooling section are not arranged in that order.

[0095] In one embodiment of the plasticizing device, The heating section, the cooling section, and the material detection section may be provided in this order from the center of the barrel toward the outside when viewed from a direction perpendicular to the groove formation surface.

[0096] According to this plasticizing device, the possibility of the material detection section being broken down by the heat of the heating section can be reduced.

[0097] In one embodiment of the plasticizing device, The shortest distance between the material detection portion and the introduction portion may be smaller than the shortest distance between the material detection portion and an outlet of the material of the hopper.

[0098] According to this plasticizing device, it is possible to reduce the amount of material remaining in the supply passage when the material detection unit detects that the material is out of material.

[0099] One embodiment of the injection molding apparatus comprises: a plasticizer for plasticizing the material into a molten material; a nozzle for injecting the molten material supplied from the plasticizer into a mold; Including, The plasticizing device comprises: a passage defining portion that is connected to a hopper that stores the material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the supply passage by rotation of the screw to generate the molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes.

[0100] One aspect of the three-dimensional printing apparatus includes: A three-dimensional printing apparatus for printing a three-dimensional object, comprising: a plasticizer for plasticizing the material into a molten material; a nozzle for ejecting the molten material supplied from the plasticizer toward a stage; Including, The plasticizing device comprises: a passage defining portion that is connected to a hopper that stores the material and defines a supply passage through which the material is supplied from the hopper; a plasticizing section having an introduction section communicating with the supply passage and a screw, the plasticizing section plasticizing the material supplied from the supply passage by rotation of the screw to generate the molten material; a material detection unit that detects the presence or absence of the material in the supply passage; Includes. [Explanation of symbols]

[0101] 10...hopper, 12...tapered portion, 14...constant width portion, 15...outlet, 16...hopper connecting pipe, 17...hollow portion, 20...injection portion, 30...mold portion, 32...molding mold, 34...cavity, 36...movable mold, 38...fixed mold, 40...mold clamping portion, 42...mold drive portion, 44...ball screw portion, 50...control portion, 60...plasticizing device, 61...plasticizing portion, 62...screw case, 64...drive motor, 70...injection control portion, 72...cylinder, 74...plunger, 76...plunger drive portion, 80...nozzle, 82...nozzle hole, 100...injection molding device, 110 ...flat screw, 111...upper surface, 112...groove forming surface, 113...side surface, 114...first groove, 115...center, 116...groove connecting portion, 117...material introduction portion, 120...barrel, 122...opposite surface, 124...second groove, 126...communicating hole, 130...heating portion, 140...check valve, 150...passage defining portion, 152...supply passage, 154...communicating hole, 160...cooling portion, 170...material detection portion, 172...tip, 200...injection molding device, 210...supply device, 300...three-dimensional modeling device, 310...stage, 312...modeling surface, 320...moving mechanism, 322...motor

Claims

1. A supply passage connected to a hopper for storing a material and through which the material is supplied from the hopper A passage defining portion defining the passage; An introduction portion communicating with the supply passage, a screw having a groove forming surface on which grooves are formed, a barrel having an opposing surface facing the groove forming surface, the opposing surface being provided with a communication hole; The material supplied from the introduction portion is plasticized by the rotation of the screw to melt the material. a plasticizer section for producing a molten material; a material detection unit that detects the presence or absence of the material in the supply passage; a nozzle connected to the communication hole and configured to eject the molten material, The plasticizing section heats the material supplied between the screw and the barrel. a heating section; and a cooling section for cooling the outer periphery of at least one of the screw and the barrel. , The communication hole allows the molten material to flow to the nozzle, The material detection unit is provided closer to the cooling unit than to the heating unit. A plasticizing device.

2. In claim 1, A control unit is included. The control unit controls the screw when the material detection unit detects that the material is out of material. and stopping the rotation of the screw.

3. In claim 1, A supply device for supplying the material to the hopper; A control unit, When the material detection unit detects that the material is out of stock, the control unit controls the supply device to A plasticizing device supplies the material to the hopper.

4. In claim 1, the passage defining portion is a case that accommodates the screw, The heating unit is provided in the barrel, The cooling unit is provided in the case, When viewed from the cross section, the material detection section, the supply passage, and the cooling section are arranged in this order from the top. This is a plasticization device.

5. In claim 4, When viewed in a direction perpendicular to the groove forming surface, the heating a plasticizing unit, a cooling unit, and a material detection unit provided in this order.

6. In any one of claims 1 to 5, The shortest distance between the material detection unit and the introduction unit is the distance between the material detection unit and the front of the hopper. The shortest distance between the outlet of the material and the plasticizer is smaller than that of the outlet of the material.

7. a plasticizer for plasticizing the material into a molten material; a nozzle for injecting the molten material supplied from the plasticizer into a mold; The plasticizing device comprises: A supply device is connected to a hopper that stores the material, and the material is supplied from the hopper. A passage defining portion that defines a passage; An introduction portion communicating with the supply passage, a screw having a groove forming surface on which grooves are formed, a barrel having an opposing surface facing the groove forming surface, the opposing surface being provided with a communication hole; The material fed from the feed section is plasticized by the rotation of the screw, a plasticizing section for producing the molten material; A material detection unit that detects the presence or absence of the material in the supply passage. 、 The plasticizing section heats the material supplied between the screw and the barrel. a heating section; and a cooling section for cooling the outer periphery of at least one of the screw and the barrel. , The material detection unit is provided closer to the cooling unit than to the heating unit. This is an injection molding device.

8. A three-dimensional printing apparatus for printing a three-dimensional object, comprising: a plasticizer for plasticizing the material into a molten material; a nozzle for discharging the molten material supplied from the plasticizer toward a stage; , including The plasticizing device comprises: A supply device is connected to a hopper that stores the material, and the material is supplied from the hopper. A passage defining portion that defines a passage; An introduction portion communicating with the supply passage, a screw having a groove forming surface on which grooves are formed, a barrel having an opposing surface facing the groove forming surface, the opposing surface being provided with a communication hole; The material fed from the feed section is plasticized by the rotation of the screw, a plasticizing section for producing the molten material; and a material detection unit that detects the presence or absence of the material in the supply passage. hand, The plasticizing section heats the material supplied between the screw and the barrel. a heating section; and a cooling section for cooling the outer periphery of at least one of the screw and the barrel. , The material detection unit is provided closer to the cooling unit than to the heating unit. This is a three-dimensional modeling device.

Images