Plasticization device and injection molding device

Abstract

To provide a technique capable of improving engineering degree of freedom of a plasticization device.SOLUTION: A plasticization device is assembled with a drive motor, a screw that has a groove formed face provided with a groove and rotates about a central axis by the drive motor, a barrel that has an opposing surface being opposite to a groove formed face in a direction along the central axis and has a communication hole where a plasticization material that is a material having been plasticized flows on an opposing surface, and a heating part for heating a material supplied to the groove. The screw has a material exit for sending a plasticization material in the groove to the communication hole, and the material exit is disposed in the screw and at a position different from the central axis.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a plasticizing device and an injection molding device. [Background technology]

[0002] Patent Document 1 discloses an injection molding apparatus equipped with a plasticizing device, and a three-dimensional modeling apparatus equipped with a plasticizing device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-154156 Summary of the Invention [Problem to be solved by the invention]

[0004] From the viewpoint of space saving and high performance, technology that increases the degree of freedom in designing plasticizing equipment is desired. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided a plasticizing device. The plasticizing device includes a drive motor, a screw having a groove-forming surface with grooves formed therein and rotated about a central axis by the drive motor, a barrel having an opposing surface facing the groove-forming surface in a direction along the central axis and having communicating holes formed in the opposing surface through which a plasticized material (a plasticized material) flows out, and a heating unit for heating the material supplied to the grooves. The screw has a material outlet for delivering the plasticized material in the grooves to the communicating holes, and the material outlet is located at a position on the screw different from the central axis.

[0006] According to a second aspect of the present disclosure, there is provided an injection molding apparatus. This injection molding apparatus includes the plasticizing device of the above aspect, a nozzle for injecting the plasticized material into a mold, a cylinder communicating with the communication hole and the nozzle, and an injection unit having a plunger moving within the cylinder, the injection unit sucking the plasticized material from the communication hole into the cylinder by movement of the plunger and delivering the plasticized material sucked into the cylinder to the nozzle. The cylinder and the nozzle are arranged along a direction perpendicular to the central axis and are aligned with each other in the perpendicular direction. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a top view showing a schematic configuration of an injection molding apparatus according to a first embodiment. [Figure 2] 1 is a perspective view showing a schematic configuration of an injection molding apparatus according to a first embodiment. [Figure 3] FIG. 2 is a perspective view showing a schematic configuration of an emission unit. [Figure 4] IV-IV cross section of Figure 3. [Figure 5] VV cross section of Figure 3. [Figure 6] FIG. 2 is a perspective view showing a schematic configuration of a flat screw. [Figure 7] FIG. 2 is a plan view showing a schematic configuration of a flat screw. [Figure 8] Cross-sectional view of VIII-VIII in Figure 7. [Figure 9] FIG. 3 is a first diagram illustrating the flow of a plasticizing material in the first embodiment. [Figure 10] FIG. 2 is a second diagram illustrating the flow of a plasticizing material in the first embodiment. [Figure 11] FIG. 2 is a diagram illustrating a schematic configuration of a first example of a plasticizing device as another embodiment. [Figure 12] FIG. 10 is a diagram showing a schematic configuration of an injection molding apparatus according to a second embodiment. [Figure 13] FIG. 10 is a diagram illustrating the flow of a plasticizing material in the second embodiment. [Figure 14]FIG. 10 is a diagram illustrating the schematic configuration of a second example of a plasticizing device as another embodiment. [Figure 15] FIG. 10 is a plan view showing a schematic configuration of a flat screw according to a third embodiment. [Figure 16] FIG. 10 is an explanatory diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] A. First embodiment: FIG. 1 is a top view showing a schematic configuration of an injection molding apparatus 10 in a first embodiment. FIG. 2 is a perspective view showing a schematic configuration of the injection molding apparatus 10. FIGS. 1 and 2 show arrows indicating mutually orthogonal X, Y, and Z directions. The X and Y directions are parallel to a horizontal plane, and the Z direction is opposite to the direction of gravity. The X, Y, and Z directions shown in FIG. 3 and subsequent figures correspond to the X, Y, and Z directions shown in FIGS. 1 and 2. In the following description, when specifying a direction, positive and negative signs are used in combination to indicate the direction indicated by the arrow, with "+" indicating the positive direction and "-" indicating the negative direction opposite to the direction indicated by the arrow.

[0009] As shown in FIGS. 1 and 2, injection molding apparatus 10 includes an injection unit 100, a mold clamping unit 130, a molding die 160, and a control unit 500. Injection molding apparatus 10 injects molding material from injection unit 100 into molding die 160 to form a molded product. The operations of injection unit 100 and mold clamping unit 130 are controlled by control unit 500. Control unit 500 is configured as a computer equipped with a CPU and memory, and controls each part of injection molding apparatus 10 by having the CPU execute a program stored in the memory. Note that control unit 500 may also be configured as a circuit.

[0010] In this embodiment, the mold clamping unit 130 is disposed alongside the injection unit 100 in the Y direction, and is disposed on the +Y direction side of the injection unit 100. A molding die 160 is attached to the mold clamping unit 130. The molding die 160 includes a fixed die 161 and a movable die 162. The fixed die 161 is a die fixed to the injection unit 100, and the movable die 162 is a die that can be moved forward and backward in the mold clamping direction relative to the fixed die 161 by the mold clamping unit 130. As a result, the molding die 160 is clamped in the mold clamping direction, which is the -Y direction in this embodiment. The molding die 160 may be made of, for example, metal, resin, or ceramic. A metal molding die 160 is called a mold.

[0011] The mold clamping device 130 has the function of opening and closing the fixed mold 161 and the movable mold 162. Under the control of the control unit 500, the mold clamping device 130 drives the mold drive unit 131 formed by a motor to rotate the ball screw 132, and moves the movable mold 162 coupled to the ball screw 132 relative to the fixed mold 161, thereby opening and closing the casting mold 160.

[0012] A hopper 30 into which material for the molded article is introduced is connected to the injection unit 100 via a communication passage 31. As the material for the molded article, for example, a thermoplastic resin formed into pellets is used. Examples of the thermoplastic resin that can be used include ABS (acrylonitrile butadiene styrene), PC (polycarbonate), POM (polyacetal), PP (polypropylene), and PBT (polybutylene terephthalate). In this embodiment, the material introduced into the hopper 30 is supplied to the injection unit 100 via the communication passage 31. The supply of material to the injection unit 100 is not limited to the hopper 30, and may be performed, for example, via a tube through which the material is pressure-fed.

[0013] The injection unit 100 plasticizes at least a portion of the material supplied from the hopper 30 to generate a molding material, and then injects the molding material into a cavity defined between the fixed mold 161 and the movable mold 162. In this specification, the molding material is also referred to as a plasticized material. In this specification, "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.

[0014] Fig. 3 is a perspective view showing a schematic configuration of the injection unit 100. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. Fig. 5 is a cross-sectional view taken along line VV in Fig. 3. The injection unit 100 of this embodiment includes a plasticizing device 110. The plasticizing device 110 includes a flat screw 111, a barrel 112, a heater 113 as a heating unit, a suction delivery unit 120, and a nozzle 114.

[0015] As shown in FIGS. 3 to 5 , the flat screw 111 is housed in the housing 101. For convenience of illustration, the housing 101 is schematically indicated by a dashed line in FIG. 3 . The flat screw 111 is also referred to as a rotor or simply a screw. The flat screw 111 is rotated within the housing 101 by a drive motor 118 around a drive shaft 119 of the drive motor 118. A central axis RX, which is the rotation center of the flat screw 111, coincides with the center of the drive shaft 119 of the drive motor 118 in the XZ plane. In this embodiment, the axial directions of the drive shaft 119 and the central axis RX are aligned along the Y direction. The rotation of the flat screw 111 by the drive motor 118 is controlled by the control unit 500. The rotation direction RD of the flat screw 111 is expressed as either a clockwise direction or a counterclockwise direction. In this embodiment, the rotation direction RD is clockwise when the flat screw 111 is viewed from the +Y direction toward the −Y direction. The flat screw 111 may be driven by a drive motor 118 via a reducer.

[0016] 4 and 5, the flat screw 111 has a groove forming surface 201 on which grooves 202 are formed. In this embodiment, the groove forming surface 201 is the surface on the +Y direction side of the flat screw 111. Details of the groove forming surface 201 will be described later.

[0017] The barrel 112 has an opposing surface 212. The opposing surface 212 faces the groove forming surface 201 in the direction along the drive shaft 119. In this embodiment, the opposing surface 212 is the surface on the −Y direction side of the barrel 112 and faces the groove forming surface 201 in the Y direction. A communicating hole 115 is formed in the opposing surface 212. As shown in FIG. 4 , in this embodiment, the communicating hole 115 is disposed at a position different from the central axis RX. That is, the communicating hole 115 is disposed at a position that does not overlap with the central axis RX when viewed in the Y direction. The communicating hole 115 is also disposed at a position in the XZ direction that allows it to face a material outlet 206 of the flat screw 111, which will be described later. More specifically, the communicating hole 115 is disposed at a position that allows it to overlap with the material outlet 206 at any rotational position in the rotation of the flat screw 111 about the central axis RX when viewed in the Y direction. In this embodiment, the communicating hole 115 is disposed on the −X direction side of the central axis RX. Note that a guide groove for guiding the plasticized material to the communicating hole 115 may be formed on the opposing surface 212. The guide groove may or may not be connected to the communicating hole 115.

[0018] The communication hole 115, together with a cylinder 121 described below, constitutes at least a part of a flow path 116 for the plasticizing material. A nozzle 114 is connected to the flow path 116. A check valve (not shown) is provided in the flow path 116 upstream of the cylinder 121. The check valve prevents backflow of the plasticizing material from the nozzle 114 side to the flat screw 111 side. The check valve is configured, for example, by a ball check valve having a ball as a valve body.

[0019] The heater 113 heats the barrel 112 and the cylinder 121. Heating by the heater 113 is controlled by the control unit 500. As shown in FIG. 5 , in this embodiment, two rod-shaped heaters 113 are arranged along the X direction so as to sandwich the cylinder 121 from the +Z direction side and the −Z direction side, respectively. The number and arrangement of the heaters 113 are not limited to those described above. For example, the number of heaters 113 may be one, or three or more. The heater 113 may be arranged at any position, such as on the +Y direction side or the −Y direction side of the cylinder 121. The heater 113 may be arranged in any orientation.

[0020] As shown in FIGS. 3 to 5, the suction and delivery unit 120 includes a cylinder 121, a plunger 122, and a plunger driver 123. The plunger driver 123 is shown in a simplified schematic form in FIG. 4. The plunger driver 123 is omitted from FIG. 3. As shown in FIG. 5, the cylinder 121 communicates with the communication hole 115 and the nozzle 114. In this embodiment, the cylinder 121 is connected to the communication hole 115. The cylinder 121 has a substantially cylindrical shape. The cylinder 121 is also referred to as a sleeve. The cylinder 121 is disposed such that its axial direction is aligned with the X direction, i.e., extends in the X direction. In this embodiment, the extension direction of the cylinder 121 and the extension direction of the nozzle 114 are perpendicular to each other. The extension direction of the nozzle 114 specifically refers to the direction in which a flow path in the nozzle 114 extends, which is the Y direction in this embodiment. In this embodiment, the extending direction of the cylinder 121 and the mold clamping direction are perpendicular to each other.

[0021] The plunger 122 has a generally cylindrical shape that is long in the axial direction of the plunger 122. The plunger 122 is disposed in the cylinder 121 so that the axial direction of the plunger 122 is along the X direction. The plunger 122 is configured to be movable in the cylinder 121 in the X direction.

[0022] The plunger driving unit 123 moves the plunger 122 within the cylinder 121. As shown in FIG. 1 , in this embodiment, the plunger driving unit 123 is configured as a driving unit having a ball screw 126 that moves the plunger 122 along the extension direction of the cylinder 121, a motor 127 that drives the ball screw 126, and a transmission mechanism 128 that transmits the driving force of the motor 127 to the ball screw 126. The ball screw 126 and the transmission mechanism 128 are disposed within the case 102. The case 102 is fixed to the housing 101 so as to protrude from the housing 101 in the +X direction. The ball screw 126 is disposed within the case 102 so as to protrude from the housing 101 in the +X direction. With this configuration, a portion of the suction and delivery unit 120 in this embodiment is disposed so as to protrude from the plasticizing device 110 in the +X direction.

[0023] Returning to Fig. 4, in the following description, the movement of the plunger 122 in the flow path 116 toward the nozzle 114 is also referred to as "advancing," and the movement of the plunger 122 in the flow path 116 away from the nozzle 114 is also referred to as "retreating." In this embodiment, when advancing, the plunger 122 moves in the -X direction toward the communication hole 115. When retracting, the plunger 122 moves in the +X direction away from the communication hole 115.

[0024] In the suction and delivery unit 120, the plunger driver 123 is controlled by the control unit 500 to perform a suction operation and a delivery operation. The suction operation is an operation in which the plasticized material is sucked into the cylinder 121 from the flow path 116 by retracting the plunger 122. The suction operation is also called a metering operation. The delivery operation is an operation in which the plasticized material sucked into the cylinder 121 is delivered to the nozzle 114 by advancing the plunger 122. The control unit 500 controls the injection amount, injection speed, and injection pressure of the plasticized material from the nozzle 114 by adjusting the movement amount and movement speed of the plunger 122 during the suction operation and the delivery operation.

[0025] FIG. 6 is a perspective view showing a schematic configuration of the flat screw 111. FIG. 7 is a plan view showing a schematic configuration of the flat screw 111. The flat screw 111 has a generally cylindrical shape with a height in the direction along the central axis RX smaller than its diameter. As described above, a spiral groove 202 is formed on the groove forming surface 201 of the flat screw 111 facing the barrel 112. In this embodiment, there is one groove 202. The groove 202 is formed by being separated by a ridge portion 204. The ridge portion 204 has a shape that protrudes further in the +Y direction than the groove 202. Note that in FIGS. 6 and 7, the groove 202 is hatched.

[0026] In this embodiment, the grooves 202 are spiral-shaped, spiraling from the outside to the inside of the groove-forming surface 201. That is, when viewed in the Y direction, the grooves 202 are spiral-shaped, spiraling from the peripheral edge portion 209 of the flat screw 111 toward the central portion 205. The peripheral edge portion 209 is a portion of the flat screw 111 that is outer than the central portion 205. The peripheral edge portion 209 includes the outer peripheral surface 221, which is the side surface of the flat screw 111. In this disclosure, the term "spiral-shaped" includes a helical shape and an involute curve shape. In this embodiment, the grooves 202 are involute curve shapes.

[0027] In the present disclosure, the direction in which the grooves 202 spiral from the outside to the inside on the groove formation surface 201 is also referred to as the "spiral direction SD." The spiral direction SD is expressed as either a clockwise direction or a counterclockwise direction. As shown in FIG. 7, the spiral direction SD in this embodiment is the clockwise direction when the grooves 202 are viewed from the +Y direction side toward the -Y direction. As shown in FIGS. 6 and 7, in this embodiment, the spiral direction SD and the rotation direction RD are the same direction.

[0028] In the following, the direction along the groove 202 will also be referred to as the groove direction GD. As shown in Fig. 7, the groove direction GD in this embodiment is the direction from the first end 202a of the groove 202 to the second end 202b. The first end 202a is located on the inner side of the two ends of the groove 202. More specifically, in this embodiment, the first end 202a is located in the central portion 205, and the second end 202b is located in the peripheral portion 209.

[0029] 6 and 7, the flat screw 111 has a material outlet 206 for delivering the plasticized material in the groove 202 to the communicating hole 115. In this embodiment, the material outlet 206 is provided at the second end 202b.

[0030] The flat screw 111 has a material inlet 222 for introducing a material into the groove 202. More specifically, the material inlet 222 is formed inside the flat screw 111 and passes through the inside of the flat screw 111 to supply the material from outside the groove 202 to the groove 202.

[0031] The material inlet 222 has a first opening 226 and a second opening 227. The first opening 226 is an opening for introducing the material into the material inlet 222. In this embodiment, the first opening 226 is provided on the outer circumferential surface 221 of the flat screw 111. As shown in FIG. 5, the first opening 226 is connected to the communication passage 31. As shown in FIGS. 6 and 7, in this embodiment, the opening shape of the first opening 226 is circular.

[0032] The second opening 227 is an opening for supplying the material in the material inlet 222 to the groove 202. Therefore, the second opening 227 is located downstream of the first opening 226 in the flow of material in the plasticizing device 110. In this embodiment, the opening shape of the second opening 227 is circular. The second opening 227 is provided in the groove forming surface 201 so as to communicate with the groove 202. The second opening 227 is also located at a position on the groove forming surface 201 that is different from the central axis RX and is located more inward than the material outlet 206. More specifically, as shown in FIG. 7 , the second opening 227 is located within a range AR on the groove forming surface 201. The range AR is a range on the groove forming surface 201 that is a distance from the central axis RX that is equal to or less than one-third of the radius r1 of the groove forming surface 201.

[0033] As shown in FIGS. 6 and 7 , in this embodiment, the material inlet 222 has a first inlet 223 and a second inlet 224. The first inlet 223 has a first opening 226. The first inlet 223 extends in a first direction D1 from the outside to the inside of the flat screw 111. In this embodiment, the first direction D1 is the −Z direction. The opening cross section of the material inlet 222 is circular. In this embodiment, the first inlet 223 has approximately the same opening diameter throughout the Z direction. The second inlet 224 is connected to the first inlet 223 at the end of the first inlet 223 on the −Z direction side. The second inlet 224 has a second inlet 224. The second inlet 224 extends in a second direction D2 within the flat screw 111. The second direction D2 intersects with the first direction D1. In this embodiment, the second direction D2 is the +Y direction. In this embodiment, the second inlet 224 has approximately the same opening diameter throughout the Y direction. Hereinafter, the portion of the first inlet 223 that is connected to the second inlet 224 will also be referred to as a connection portion 228. In other words, the connection portion 228 is the end of the first inlet 223 on the -Z direction side.

[0034] In this embodiment, the material supplied from the hopper 30 to the injection unit 100 is first introduced into the first inlet 223 via the communication passage 31 and the first opening 226. Next, the material in the first inlet 223 travels through the first inlet 223 in the −Z direction and is then supplied to the second inlet 224 via the connecting portion 228. The material in the second inlet 224 then travels through the second inlet 224 in the +Y direction and is then supplied into the groove 202 via the second opening 227. The material supplied into the groove 202 is plasticized by the rotation of the flat screw 111 and the heat of the heater 113, moves within the groove 202 from the center 205 to the periphery 209, and reaches the material outlet 206. As a result, the plasticized material is sent out to the communication hole 115 via the material outlet 206.

[0035] FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. 7. As shown in FIGS. 7 and 8, the groove 202 has a first groove portion 207 and a second groove portion 208 in the groove direction GD. As shown in FIG. 7, the first groove portion 207 is located closer to the first end 202a, and the second groove portion 208 is located closer to the second end 202b in the groove direction GD. Also, as shown in FIGS. 7 and 8, the second groove portion 208 is located further outward than the first groove portion 207 on the groove formation surface 201. As shown in FIG. 8, in this embodiment, the depth DP1 of the first groove portion 207 is deeper than the depth DP2 of the second groove portion 208. More specifically, in this embodiment, the groove 202 is configured so that its depth gradually decreases from the first end 202a toward the second end 202b. In this embodiment, the depth of the groove 202 means the distance that the groove 202 is recessed in the -Y direction from the adjacent ridge portion 204. In addition, the depth DP3 of the material outlet 206 located further outside than the second groove portion 208 is shallower than the depth DP2.

[0036] FIG. 9 is a first diagram illustrating the flow PA of the plasticized material in the first embodiment. FIG. 10 is a second diagram illustrating the flow PA of the plasticized material in the first embodiment. The flow PA represents the flow of the plasticized material downstream of the material outlet 206 of the flat screw 111. As shown in FIGS. 9 and 10 , in this embodiment, the plasticized material delivered from the material outlet 206 to the communicating hole 115 is drawn into the cylinder 121 by the suction operation of the plunger 122, and is delivered from the cylinder 121 to the nozzle 114 by the delivery operation of the plunger 122. As a result, in this embodiment, when the plasticized material is delivered from the cylinder 121 to the nozzle 114, the movement direction of the plasticized material is changed from the −X direction to the +Y direction between the cylinder 121 and the nozzle 114.

[0037] FIG. 11 is a diagram illustrating a first example of the schematic configuration of a plasticizing apparatus 600 according to another embodiment. Unlike the plasticizing apparatus 110 of the first embodiment, the plasticizing apparatus 600 has a material outlet 602 of the flat screw 601 aligned on the central axis RX. Similar to FIGS. 9 and 10, FIG. 11 illustrates a flow PA. Similarly to the plasticizing apparatus 110, the plasticizing apparatus 600 converts the direction of movement of the plasticized material from the −X direction to the +Y direction between the cylinder 121 and the nozzle 114. In the plasticizing apparatus 600, the communicating hole 604 of the barrel 603 is aligned on the central axis RX, corresponding to the material outlet 602. On the other hand, as shown in FIG. 9, the communicating hole 115 in the plasticizing apparatus 110 is positioned at a distance Ds1 from the central axis RX toward the −X direction. As a result, in the plasticizing apparatus 110, the cylinder 121 is positioned a distance Ds1 further in the -X direction than in the plasticizing apparatus 600 shown in Figure 11. With this configuration, in the plasticizing apparatus 110, the entire suction and feeding section 120 can be positioned a distance Ds1 further in the -X direction than in the plasticizing apparatus 600, and the length of the portion of the suction and feeding section 120 shown in Figures 1 and 2 that protrudes in the +X direction can be reduced. In this manner, in this embodiment, by arranging the material outlet 206 at a position different from the central axis RX, the protrusion of the suction and feeding section 120 can be suppressed, and the injection molding apparatus 10 can be configured to be more space-saving.

[0038] According to the plasticizing device 110 of the present embodiment described above, the material outlet 206 of the flat screw 111 is disposed at a position on the flat screw 111 that is different from the central axis RX. This configuration allows the communicating hole 115 to be disposed at a position offset from the central axis RX, thereby improving the flexibility in the placement of the communicating hole 115. More specifically, as shown in FIG. 11 , in a configuration in which the material outlet 602 is disposed on the central axis RX, the communicating hole 604 needs to be disposed in a relatively narrow region overlapping the central axis RX when viewed in the Y direction. In contrast, in this embodiment, the communicating hole 115 does not need to be disposed in a region overlapping the central axis RX when viewed in the Y direction. Therefore, the communicating hole 115 can be disposed in a relatively wide region, improving the design flexibility of the plasticizing device 110. Furthermore, as a result, in various devices equipped with the plasticizing device 110, such as the injection molding device 10, the design flexibility of the configuration downstream of the communicating hole 115 can be improved.

[0039] In this embodiment, the groove forming surface 201 has a spiral shape that spirals from the outside to the inside, and the spiral direction SD in which the grooves 202 spiral from the outside to the inside is the same direction as the rotation direction RD of the flat screw 111. Therefore, by rotating the flat screw 111 in the rotation direction RD, the material and plasticized material in the grooves 202 can be smoothly moved from the inside to the outside, and the plasticized material in the grooves 202 can be smoothly delivered to the communicating holes 115.

[0040] Furthermore, in this embodiment, the depth DP1 of the first groove portion 207 of the groove 202 is deeper than the depth DP2 of the second groove portion 208 located outside the first groove portion 207. Therefore, compared to when the depth of the groove 202 is the same throughout the groove direction GD, for example, the material supplied to the groove 202 can be efficiently swept from the inside to the outside along the groove 202, and the pressure of the material and plasticized material on the material outlet 206 side of the groove 202 can be effectively increased. As a result, the plasticized material in the groove 202 can be more efficiently delivered to the communicating hole 115.

[0041] Furthermore, in this embodiment, the first opening 226 of the material inlet 222 is provided on the outer peripheral surface 221 of the flat screw 111. Therefore, the material can be introduced into the groove 202 from the outer peripheral surface 221 side of the flat screw 111. Here, in another embodiment, for example, if the first opening 226 is provided on the surface on the −Y direction side of the flat screw 111, at least a part of the components for supplying the material to the flat screw 111, such as the communicating passage 31 and the hopper 30, must be arranged on the −Y direction side of the flat screw 111. As a result, the communicating passage 31 and the hopper 30 are likely to interfere with the drive motor 118 and the reducer. In this embodiment, because the material can be supplied from the outer peripheral surface 221 side of the flat screw 111, it is easier to arrange the communicating passage 31 and the hopper 30 to avoid the drive motor 118 and the reducer, thereby suppressing such interference.

[0042] In this embodiment, the second opening 227 of the material introduction port 222 is disposed at a position on the groove forming surface 201 that is different from the central axis RX and that is more inward than the material outlet 206. Therefore, the material can be supplied from the outer circumferential surface 221 side of the flat screw 111 to a more appropriate position on the groove forming surface 201 via the first opening 226 and the second opening 227.

[0043] Furthermore, in this embodiment, the second opening 227 is arranged within the range AR on the groove forming surface 201. According to this embodiment, the path of the material from the second opening 227 to the material outlet 206 within the groove 202 can be made longer than when the second opening 227 is arranged outside the range AR on the groove forming surface 201, and therefore the material can be plasticized more effectively.

[0044] B. Second embodiment: FIG. 12 is a diagram showing a schematic configuration of an injection molding apparatus 10b in the second embodiment. In the injection section 100b in this embodiment, unlike the first embodiment, the cylinder 121 and the nozzle 114 are arranged along an orthogonal direction perpendicular to the central axis RX. Furthermore, the cylinder 121 and the nozzle 114 are arranged side by side in the orthogonal direction. The plasticizing device 110b and the injection molding apparatus 10b in this embodiment are similar to those in the first embodiment unless otherwise specifically described. Note that FIG. 12 shows a flow PA, similar to FIG. 9.

[0045] In this embodiment, the orthogonal direction is the Z direction. Therefore, the extension direction of the cylinder 121 and the extension direction of the nozzle 114 are both the Z direction. The cylinder 121 and the nozzle 114 are arranged side by side in the Z direction. The nozzle 114 is arranged on the +X direction side of the cylinder 121. The cylinder 121 and the nozzle 114 are connected by a connecting flow path 117 along the Z direction. As a result, the flow path 116A from the cylinder 121 to the nozzle 114 is configured linearly along the Z direction. The flow path 116A includes a flow path within the cylinder 121 and the connecting flow path 117. Although not shown in the drawings, in this embodiment, the mold clamping unit 130 is arranged on the +X direction side of the plasticizing unit 110b. Furthermore, the mold clamping direction in this embodiment is the -X direction.

[0046] In the plasticizing device 110b of this embodiment, the communication hole 115 is disposed on the +X direction side of the central axis RX. More specifically, as shown in Fig. 12, the communication hole 115 is disposed at a distance Ds2 from the central axis RX on the +X direction side.

[0047] 13 is a diagram illustrating the flow PA of the plasticized material in the second embodiment. As shown in FIGS. 12 and 13, in this embodiment, unlike the first embodiment, the movement direction of the plasticized material remains in the +X direction between the cylinder 121 and the nozzle 114.

[0048] FIG. 14 is a diagram illustrating the schematic configuration of a second example of an injection molding apparatus 700 as another embodiment. In a plasticizing apparatus 702 provided in an injection section 701 of the injection molding apparatus 700, the material outlet 602 is arranged on the central axis RX, similar to the plasticizing apparatus 600 shown in FIG. 11. FIG. 14 shows a flow PA, similar to FIGS. 12 and 13. In the injection molding apparatus 700, the movement direction of the plasticized material between the cylinder 121 and the nozzle 114 remains in the +X direction and is not changed, similar to the plasticizing apparatus 110b in the second embodiment.

[0049] In the plasticizing device 702 shown in FIG. 14 , similar to the plasticizing device 600 shown in FIG. 11 , the communication hole 604 is disposed on the central axis RX corresponding to the material outlet 602. On the other hand, as described above, in the plasticizing device 110b shown in FIG. 12 , the communication hole 115 is disposed at a distance Ds2 from the central axis RX, toward the +X direction. As a result, the connection flow path 117 shown in FIG. 12 is shorter by the distance Ds2 compared to the connection flow path 703 shown in FIG. 14 . As described above, in this embodiment, the material outlet 206 is disposed at a position different from the central axis RX, thereby preventing an increase in the length of the connection flow path 117 and thus preventing an increase in the length of the flow path 116A. When the flow path 116A is shorter, air is less likely to accumulate in the flow path 116A than when the flow path 116A is longer, and therefore, preventing air in the flow path 116A from interfering with the delivery of the material from the cylinder 121 to the nozzle 114.

[0050] In the injection molding apparatus 10b of the second embodiment described above, the cylinder 121 and the nozzle 114 are arranged along the X direction, which is perpendicular to each other, and are aligned with each other in the X direction. Therefore, the flow path 116A from the cylinder 121 to the nozzle 114 can be configured linearly along the Z direction. This reduces pressure loss of the plasticized material in the flow path 116A compared to a configuration in which the flow path 116A is not linear. Furthermore, by positioning the communication hole 115 at a position offset from the central axis RX corresponding to the material outlet 206, the flow path 116A can be made shorter compared to a configuration in which the communication hole 115 is positioned on the central axis RX. As a result, pressure loss of the plasticized material while it is being delivered from the cylinder 121 to the nozzle 114 can be effectively reduced, allowing the plasticized material to be injected into the molding die 160 at higher speeds and higher pressures.

[0051] C. Third embodiment: 15 is a plan view showing a schematic configuration of a flat screw 111c in the third embodiment. In the third embodiment, the configuration of a first inlet 223c in a material inlet 222c provided in the flat screw 111c is different from that in the first embodiment. The plasticizing device 110 and the injection molding device 10 in this embodiment are the same as those in the first embodiment except for the points not specifically described.

[0052] In the present embodiment, the first inlet 223c has a first portion 231 and a second portion 232 in the first direction D1. The second portion 232 is located more inward than the first portion 231 in the first direction D1. An opening diameter AD1 of the first portion 231 is larger than an opening diameter AD2 of the second portion 232. Furthermore, for example, when the first opening 226 is the first portion and the connecting portion 228 is the second portion, the opening diameter of the first opening 226 is larger than the opening diameter of the connecting portion 228. More specifically, in the present embodiment, the opening diameter of the first inlet 223c is configured to gradually decrease as it progresses from the first opening 226 toward the connecting portion 228 in the first direction D1.

[0053] According to the plasticizing device 110 of the third embodiment described above, the opening diameter AD1 of the first portion 231 of the first inlet 223c is larger than the opening diameter AD2 of the second portion 232 of the first inlet 223c that is located more inward than the first portion 231 in the first direction D1. Therefore, for example, compared to when the first inlet 223c has the same opening diameter throughout the first direction D1, the outlet side portion of the first inlet 223c can be configured to be more space-saving and stagnation of the material movement at the inlet side portion of the first inlet 223c can be suppressed. In this way, in this embodiment, the material inlet 222c can be configured to be more space-saving and stagnation of the introduction of the material into the groove 202 via the material inlet 222c can be suppressed.

[0054] D. Fourth embodiment: 16 is an explanatory diagram showing a schematic configuration of a three-dimensional modeling apparatus 400 according to the fourth embodiment. The three-dimensional modeling apparatus 400 includes a plasticizing apparatus 110, a stage 410, and a moving mechanism 420.

[0055] The plasticizing device 110 in the second embodiment is provided with a valve 430 in the flow path 116, instead of a check valve, that switches the amount of plasticizing material discharged from the nozzle 114 or whether or not to discharge the material. The valve 430 is driven under the control of the control unit 450. The other configurations of the plasticizing device 110 are the same as those of the plasticizing device 110 in the first embodiment.

[0056] The stage 410 faces the nozzle 114. The plasticized material ejected from the nozzle 114 is deposited on the stage 410. The stage 410 is supported by a movement mechanism 420.

[0057] The movement mechanism 420 changes the relative position between the nozzle 114 and the stage 410. In this embodiment, the movement mechanism 420 changes the relative position between the nozzle 114 and the stage 410 by moving the stage 410. In this embodiment, the movement mechanism 420 is configured with a three-axis positioner that moves the stage 410 in three axial directions (X, Y, and Z) using power generated by three motors. Each motor is driven under the control of the control unit 450. Note that the movement mechanism 420 may be configured to change the relative position between the nozzle 114 and the stage 410 by moving the plasticizing device 110 without moving the stage 410. Alternatively, the movement mechanism 420 may be configured to change the relative position between the nozzle 114 and the stage 410 by moving both the stage 410 and the plasticizing device 110.

[0058] Under the control of the control unit 450, the three-dimensional modeling apparatus 400 discharges plasticized material from the nozzle 114 while changing the relative position between the nozzle 114 and the stage 410, thereby stacking layers of plasticized material onto the stage 410 to form a three-dimensional object of a desired shape. When the control unit 450 temporarily stops the discharge of plasticized material from the nozzle 114 using the valve 430, it drives the plunger 122 to suck the plasticized material around the nozzle 114 into the cylinder 121. When the control unit 450 resumes the discharge of plasticized material from the nozzle 114 using the valve 430, it drives the plunger 122 to pressure-feed the plasticized material sucked into the cylinder 121 toward the nozzle 114.

[0059] In this embodiment, as in the first embodiment, the material outlet 206 of the flat screw 111 is disposed at a position different from the central axis RX. Furthermore, the communication hole 115 of the barrel 112 is disposed at a position different from the central axis RX in correspondence with the material outlet 206. Specifically, in Fig. 16, the communication hole 115 is disposed at a position shifted from the central axis RX in a direction perpendicular to the extension direction of the cylinder 121 and the central axis RX.

[0060] E. Other Embodiments: (E-1) In each of the above embodiments, the plasticizing device 110 may include a control unit that controls the drive motor 118 to rotate the flat screw 111 in the rotation direction RD. That is, the plasticizing device 110 may include, for example, a control unit 500 or a control unit 450. In this case, the control unit included in the plasticizing device 110 controls the drive motor 118 to rotate the flat screw 111 in the rotation direction RD, thereby allowing the plasticized material in the groove 202 to be sent to the communicating hole 115.

[0061] (E-2) In each of the above embodiments, the depth DP1 of the first groove portion 207 is deeper than the depth DP2 of the second groove portion 208. However, the depth DP1 may be equal to or less than the depth DP2.

[0062] (E-3) In each of the above embodiments, the first opening 226 does not have to be provided on the outer peripheral surface 221 of the flat screw 111. For example, the first opening 226 may be provided on the surface of the flat screw 111 opposite to the groove forming surface 201.

[0063] (E-4) In the above embodiments, the second opening 227 is disposed within the range AR, but it may be disposed outside the range AR. Furthermore, the second opening 227 does not have to be disposed at a position different from the central axis RX, and may be disposed on the central axis RX.

[0064] (E-5) In each of the above embodiments, the material inlet 222 has the first inlet 223 and the second inlet 224. However, the material inlet 222 does not necessarily have to have the first inlet 223 and the second inlet 224. For example, the material inlet 222 may be configured as a linear through-hole that passes through the flat screw 111 in the height direction, or as a linear hole that connects the outer circumferential surface 221 of the flat screw 111 and the groove 202. Furthermore, the shape and arrangement of the material inlet 222 are not limited to those described above, and may be any shape or arrangement. For example, the shape of the material inlet 222 is not limited to a linear shape, and may be any shape, such as a curved shape or a shape that combines one or more linear holes with one or more curved holes.

[0065] (E-6) In each of the above embodiments, the number of grooves 202 is 1. However, the number of grooves 202 may be 2 or more.

[0066] (E-7) In each of the above embodiments, the groove 202 is spiral-shaped. However, the groove 202 is not limited to a spiral shape, and may be, for example, an arc-shaped groove extending from the central portion 205 toward the peripheral portion 209.

[0067] (E-8) In each of the above embodiments, the barrel 112 may be provided with a plurality of communication holes 115. This allows for a simple configuration to provide a plurality of nozzles 114 in the injection molding apparatus 10 or the three-dimensional modeling apparatus 400. In this case, by providing a plurality of grooves 202 and material outlets 206 in the groove forming surface 201 and providing a plurality of material inlets 222 for introducing material into each groove 202, it is possible to easily deliver the plasticized material from each groove 202 to each communication hole 115 simultaneously.

[0068] 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.

[0069] (1) According to a first aspect of the present disclosure, there is provided a plasticizing device. The plasticizing device includes a drive motor, a screw having a groove-forming surface with grooves formed therein and rotated about a central axis by the drive motor, a barrel having an opposing surface facing the groove-forming surface in a direction along the central axis and having communicating holes formed in the opposing surface through which a plasticized material (a plasticized material) flows out, and a heating unit for heating the material supplied to the grooves. The screw has a material outlet for delivering the plasticized material in the grooves to the communicating holes, and the material outlet is located at a position on the screw different from the central axis. According to this embodiment, the communicating holes can be disposed at positions offset from the central axis of the screw, which increases the degree of freedom in arranging the communicating holes and therefore increases the degree of freedom in designing the plasticizing device.

[0070] (2) In the above embodiment, the grooves may have a spiral shape that spirals from the outside to the inside of the groove-forming surface, and the spiral direction of the grooves that spirals from the outside to the inside may be the same as the rotation direction of the screw. According to this embodiment, by rotating the screw in the rotation direction, the plasticized material in the grooves can be smoothly moved from the inside to the outside of the groove-forming surface, and the plasticized material in the grooves can be smoothly delivered to the communicating holes.

[0071] (3) In the above embodiment, the groove may have a first groove portion and a second groove portion in a direction along the groove, the second groove portion being located outward of the first groove portion on the groove-forming surface, and the first groove portion may be deeper than the second groove portion. This embodiment allows the plasticized material in the groove to be more efficiently delivered to the communicating hole.

[0072] (4) In the above embodiment, the plasticizing device may further include a control unit that controls the drive motor so that the screw rotates in the rotation direction. According to this embodiment, the control unit provided in the plasticizing device controls the drive motor to rotate the screw in the rotation direction, thereby allowing the plasticized material in the grooves to be delivered to the communicating holes.

[0073] (5) In the above embodiment, the screw may have a material inlet for introducing the material into the groove, the material inlet having a first opening for introducing the material into the material inlet, and the first opening may be provided on the outer circumferential surface of the screw. According to this embodiment, the material can be introduced into the groove from the outer circumferential surface side of the screw.

[0074] (6) In the above embodiment, the material inlet may have a second opening for supplying the material in the material inlet to the groove, and the second opening may be disposed at a position on the groove forming surface different from the central axis and more inward than the material outlet. According to this embodiment, the material can be supplied to a more appropriate position on the groove forming surface of the screw via the first opening and the second opening.

[0075] (7) In the above embodiment, the second opening may be located within a range of one-third of the radius of the groove-forming surface from the central axis. This embodiment allows the material path within the groove to be longer, thereby more effectively plasticizing the material.

[0076] (8) In the above embodiment, the material introduction port may include a first introduction port having the first opening and extending within the screw in a first direction from the outside to the inside of the screw, and a second introduction port connected to the first introduction port and having the second opening and extending within the screw in a second direction intersecting the first direction, the first introduction port having a first portion and a second portion located more inward than the first portion in the first direction, and the opening diameter of the first portion may be larger than the opening diameter of the second portion. This embodiment allows the material introduction port to be configured in a more space-saving manner and prevents stagnation of the introduction of material into the groove through the material introduction port.

[0077] (9) According to a second aspect of the present disclosure, there is provided an injection molding apparatus. This injection molding apparatus includes the plasticizing device of the above aspect, a nozzle for injecting the plasticized material into a mold, a cylinder communicating with the communication hole and the nozzle, and an injection unit having a plunger moving within the cylinder, the injection unit sucking the plasticized material from the communication hole into the cylinder by movement of the plunger and delivering the plasticized material sucked into the cylinder to the nozzle. The cylinder and the nozzle are arranged along a direction perpendicular to the central axis and aligned with each other in the perpendicular direction. According to this configuration, the flow path from the cylinder to the nozzle can be configured in a straight line along the perpendicular direction, thereby suppressing pressure loss of the plasticized material in the flow path from the cylinder to the nozzle. Furthermore, by arranging the communication hole at a position offset from the central axis corresponding to the material outlet, the flow path from the cylinder to the nozzle can be made shorter compared to when the communication hole is arranged on the central axis. As a result, pressure loss of the plasticized material while it is being sent from the cylinder to the nozzle can be effectively suppressed, allowing the plasticized material to be injected into the mold at higher speeds and pressures.

[0078] The present disclosure is not limited to the above-described plasticizing device and injection molding device, but can be realized in various forms, such as a three-dimensional modeling device and a plasticizing method. [Explanation of symbols]

[0079] 10, 10b... injection molding apparatus, 30... hopper, 31... communicating passage, 100, 100b... injection section, 101... storage section, 102... case, 110, 110b... plasticizing device, 111, 111c... flat screw, 112... barrel, 113... heater, 114... nozzle, 115... communicating hole, 116, 116A... flow path, 117... connecting flow path, 118... drive motor , 119...drive shaft, 120...suction delivery section, 121...cylinder, 122...plunger, 123...plunger drive section, 126...ball screw, 127...motor, 128...transmission mechanism, 130...mold clamping device, 131...mold drive section, 132...ball screw, 160...forming die, 161...fixed die, 162...movable die, 201...groove forming surface, 202...groove, 202a...first end , 202b...Second end, 204...Convex strip, 205...Central part, 206...Material outlet, 207...First groove part, 208...Second groove part, 209...Peripheral part, 212...Opposing surface, 221...Outer peripheral surface , 222, 222c...Material introduction port, 223,223c...First introduction port, 224...Second introduction port, 226...First opening, 227...Second opening, 228...Connection part, 231...First part , 232...second part, 241...upper surface, 400...three-dimensional modeling device, 410...stage, 420...movement mechanism, 430...valve, 450...control part, 500...control part, 600...plasticizing device, 601...flat screw, 602...material outlet, 603...barrel, 604...communicating hole, 700...injection molding device, 701...injection part, 702...plasticizing device, 703...connecting flow path

Claims

1. A plasticizing device comprising: A drive motor; a screw having a groove forming surface on which grooves are formed and rotated around a central axis by the drive motor; a barrel having an opposing surface facing the groove forming surface in a direction along the central axis, the opposing surface having a communication hole through which a plasticized material flows out; a heating unit that heats the material supplied to the groove, A plasticizing device, wherein the screw has a material outlet for delivering the plasticized material in the groove to the communicating hole, and the material outlet is positioned at a position on the screw different from the central axis.

2. 2. The plasticizing device according to claim 1, The groove has a spiral shape that spirals from the outside to the inside on the groove formation surface, A plasticizing device, wherein the spiral direction of the grooves from the outside to the inside is the same as the rotation direction of the screw.

3. 3. The plasticizing device according to claim 2, The groove has a first groove portion and a second groove portion in a direction along the groove, the second groove portion is located on the groove formation surface outside the first groove portion, The depth of the first groove portion is greater than the depth of the second groove portion.

4. 3. The plasticizing device according to claim 2, The plasticizing device further comprises a control unit that controls the drive motor so that the screw rotates in the rotation direction.

5. 2. The plasticizing device according to claim 1, the screw has a material inlet for introducing the material into the groove; the material inlet has a first opening for introducing the material into the material inlet; A plasticizing device, wherein the first opening is provided on the outer peripheral surface of the screw.

6. 6. The plasticizing device according to claim 5, the material inlet has a second opening for supplying the material in the material inlet to the groove; The second opening is disposed at a position on the groove forming surface that is different from the central axis and that is more inward than the material outlet.

7. 7. The plasticizing device according to claim 6, A plasticizing device, wherein the second opening is located on the groove forming surface within a range of one-third of the radius of the groove forming surface from the central axis.

8. 7. The plasticizing device according to claim 6, The material inlet is a first inlet having the first opening and extending in a first direction from the outside of the screw toward the inside of the screw; a second inlet connected to the first inlet and having the second opening, the second inlet extending through the screw in a second direction intersecting the first direction; the first introduction port has a first portion and a second portion located more inward than the first portion in the first direction, The opening diameter of the first portion is larger than the opening diameter of the second portion.

9. 1. An injection molding apparatus comprising: A plasticizing device according to any one of claims 1 to 8; a nozzle for injecting the plasticized material into a mold; an injection unit having a cylinder communicating with the communication hole and the nozzle, and a plunger that moves within the cylinder, and which sucks the plasticized material from the communication hole into the cylinder by the movement of the plunger, and delivers the plasticized material sucked into the cylinder to the nozzle; An injection molding apparatus, wherein the cylinder and the nozzle are arranged along an orthogonal direction perpendicular to the central axis and are arranged side by side in the orthogonal direction.

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