Manufacturing method for molded products

Abstract

To provide a method for manufacturing a molded product that can reduce a possibility that reusable material forms a spiral shape.SOLUTION: A method for manufacturing a molded product includes: a first step of discharging a molding material containing a thermoplastic resin to mold a molded object, and molding a first molded product by cutting the molded object with a first rotary tool; a second step of generating reusable material by cutting the first molded product with a second rotary tool; and a third step of discharging the plasticized reusable material to mold a second molded product. In the second step, the first molded product is cut under at least one of following conditions: a moving speed of the second rotary tool is faster than the moving speed of the first rotary tool in the first step, and a rotating speed of the second rotary tool is slower than the rotating speed of the first rotary tool in the first step.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a mold.

Background Art

[0002] There is known a shaping apparatus that shapes a three-dimensional object by discharging a plasticized material toward a stage and curing it.

[0003] For example, Patent Document 1 describes a shaping apparatus that shapes a recycled material by cutting a first molded product, plasticizes the recycled material in a plasticizing section, and uses the plasticized recycled material to shape a second molded product.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when generating a recycled material by cutting, the recycled material may have a spiral shape. When the recycled material has a spiral shape, the recycled materials may interfere with each other, causing a bridging phenomenon where new recycled material is not supplied to the plasticizing section, and in some cases, the recycled material cannot be stably plasticized.

Means for Solving the Problems

[0006] One aspect of the method for manufacturing a mold according to the present invention is a first step of discharging a shaping material containing a thermoplastic resin to shape a shaped body, and forming a first molded product by cutting the shaped body with a first rotating tool; a second step of generating a recycled material by cutting the first molded product with a second rotating tool; A third step involves extruding the plasticized recycled material to form a second molded product, Includes, In the second step, the first molded product is cut under at least one of the following conditions: the moving speed of the second rotating tool is faster than the moving speed of the first rotating tool in the first step, and the rotational speed of the second rotating tool is slower than the rotational speed of the first rotating tool in the first step. [Brief explanation of the drawing]

[0007] [Figure 1] Functional block diagram of the molded product recycling system according to this embodiment. [Figure 2] A schematic perspective view showing the three-dimensional molding apparatus of the molded product recycling system according to this embodiment. [Figure 3] A schematic cross-sectional view showing the discharge unit of the molded product recycling system according to this embodiment. [Figure 4] A schematic perspective view showing the flat screw of the molded product recycling system according to this embodiment. [Figure 5] A schematic plan view showing the barrel of the molded product recycling system according to this embodiment. [Figure 6] This cross-sectional view schematically shows the manufacturing process of a molded product in a three-dimensional molding apparatus for a molded product recycling system according to this embodiment. [Figure 7] A schematic side view showing the injection molding apparatus of the molded product recycling system according to this embodiment. [Figure 8] A schematic cross-sectional view showing the injection molding apparatus of the molded product recycling system according to this embodiment. [Figure 9] This is an exploded perspective view schematically showing the mold for the molded product recycling system according to this embodiment. [Figure 10] A schematic perspective view showing the cutting device of the molded product recycling system according to this embodiment. [Figure 11] A diagram illustrating the cutting of molded parts by a rotary tool in the molded part recycling system according to this embodiment. [Figure 12]Bottom view schematically showing the rotating tool of the modeling product recycling system according to this embodiment. [Figure 13] Side view schematically showing the rotating tool of the modeling product recycling system according to this embodiment. [Figure 14] Flowchart for explaining the manufacturing method of the modeling product according to this embodiment. [Figure 15] Perspective view for explaining an experimental example. [Figure 16] Side view for explaining an experimental example. [Figure 17] Photo of the appearance of the rotating tool T used in the experimental example. [Figure 18] Table showing the cutting conditions in the experimental example. [Figure 19] Table showing the cutting conditions in the experimental example. [Figure 20] Photo of the cutting chips in the experimental example. [Figure 21] Photo of the cutting chips in the experimental example. [[ID=:30]]

Mode for Carrying Out the Invention

[0008] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Note that the embodiments described below do not unduly limit the content of the present invention described in the claims. Also, not all of the configurations described below are essential constituent elements of the present invention.

[0009] 1. Modeling Product Recycling System 1.1. Overall Configuration First, the modeling product recycling system according to this embodiment will be described with reference to the drawings. FIG. 1 is a functional block diagram of the modeling product recycling system 100 according to this embodiment.

[0010] As shown in FIG. 1, the modeling product recycling system 100 includes, for example, a three-dimensional modeling apparatus 200, an injection molding apparatus 300, and a cutting apparatus 400.

[0011] The three-dimensional molding apparatus 200 creates a first molded product from the molding material. The first molded product is used, for example, in at least a portion of the mold of the injection molding apparatus 300. The arrows in Figure 1 indicate the flow of the molding material that makes up the molded product.

[0012] The injection molding apparatus 300 performs injection molding using the first molded product as a mold. The first molded product deteriorates with repeated use. The deteriorated first molded product is removed from the injection molding apparatus 300.

[0013] The cutting device 400 cuts the first molded product 10 that has been removed from the injection molding device 300. When the first molded product 10 is cut, cutting chips are generated.

[0014] The three-dimensional molding apparatus 200 plasticizes the generated cutting chips as recycled material and extrudes them to form a second molded product. The second molded product is, for example, formed by the mold of the injection molding apparatus 300. It is used in some cases.

[0015] As described above, the molded product recycling system 100 can recycle molded products. Each device will now be explained in detail.

[0016] 1.2. Three-dimensional printing equipment Figure 2 is a schematic perspective view of the three-dimensional molding apparatus 200 of the molded product recycling system 100. In Figure 2, the three mutually orthogonal axes are shown as the X-axis, Y-axis, and Z-axis. The X-axis and Y-axis directions are, for example, horizontal directions. The Z-axis direction is, for example, vertical directions.

[0017] As shown in Figure 2, the three-dimensional molding apparatus 200 includes, for example, a molding unit 210, a cutting unit 270, a stage 280, a position changing unit 282, and a control unit 290.

[0018] The three-dimensional molding apparatus 200 extrudes the molded material from the nozzle 260 of the molding unit 210 onto the stage 280, while simultaneously driving the position change unit 282 to change the relative position between the nozzle 260 and the stage 280. As a result, the molding unit 210 creates a molded object on the stage 280.

[0019] Furthermore, the three-dimensional molding apparatus 200 rotates the first rotary tool 272 of the cutting unit 270 and drives the position change unit 282 to change the relative position between the first rotary tool 272 and the stage 280. Then, the cutting unit 270 cuts the molded body formed on the stage 280. In this way, the three-dimensional molding apparatus 200 creates a molded product 10 of the desired shape. The molded body is in the state before the cavity 12 of the molded product 10 is formed.

[0020] Here, Figure 3 is a schematic cross-sectional view showing the molding unit 210. As shown in Figure 3, the molding unit 210 includes, for example, a material supply unit 220, a plasticizing unit 230, and a nozzle 260.

[0021] The material supply unit 220 supplies the molding material to the plasticizing unit 230. The shape of the molding material supplied by the material supply unit 220 is, for example, pellets or powder. The material supply unit 220 is configured to include, for example, a hopper.

[0022] The plasticizing unit 230 includes, for example, a screw case 232, a drive motor 234, a flat screw 240, a barrel 250, and a heater 258. The plasticizing unit 230 plasticizes at least a portion of the solid molding material supplied from the material supply unit 220 to produce a fluid paste-like molding material, which is then supplied to the nozzle 260.

[0023] Plasticization is a concept that includes melting, and refers to the process of changing a solid state to a fluid state. Specifically, for materials that undergo a glass transition, plasticization means raising the material's temperature above its glass transition point. For materials that do not undergo a glass transition, plasticization means raising the material's temperature above its melting point.

[0024] The screw case 232 is a housing that contains the flat screw 240. A barrel 250 is provided on the bottom surface of the screw case 232. The flat screw 240 is housed in the space enclosed by the screw case 232 and the barrel 250.

[0025] The drive motor 234 is located on the upper surface of the screw case 232. -234 is, for example, a servo motor. The shaft 236 of the drive motor 234 is connected to the upper surface 241 of the flat screw 240. The drive motor 234 is controlled by the control unit 290. Although not shown in the figures, the shaft 236 of the drive motor 234 and the upper surface 241 of the flat screw 240 may be connected via a reduction gear.

[0026] The flat screw 240 has a substantially cylindrical shape in which the magnitude in the direction of the rotation axis R is smaller than the magnitude in the direction perpendicular to the rotation axis R. In the illustrated example, the rotation axis R is parallel to the Z axis. The torque generated by the drive motor 234 causes the flat screw 240 to rotate around the rotation axis R.

[0027] The flat screw 240 has an upper surface 241, a groove-forming surface 242 opposite to the upper surface 241, and a side surface 243 connecting the upper surface 241 and the groove-forming surface 242. A first groove 244 is formed in the groove-forming surface 242. The side surface 243 is, for example, perpendicular to the groove-forming surface 242. Here, Figure 4 is a schematic perspective view of the flat screw 240. For convenience, Figure 4 shows the state with the vertical positional relationship reversed compared to the state shown in Figure 3.

[0028] As shown in Figure 4, a first groove 244 is formed on the groove-forming surface 242 of the flat screw 240. The first groove 244 has, for example, a central portion 245, a connecting portion 246, and a material introduction portion 247. The central portion 245 faces a communication hole 256 formed in the barrel 250. The central portion 245 communicates with the communication hole 256. The connecting portion 246 connects the central portion 245 and the material introduction portion 247. In the illustrated example, the connecting portion 246 is arranged in a spiral shape from the central portion 245 toward the outer circumference of the groove-forming surface 242. The material introduction portion 247 is provided on the outer circumference of the groove-forming surface 242. That is, the material introduction portion 247 is provided on the side surface 243 of the flat screw 240. The material supplied from the material supply unit 220 is introduced into the first groove 244 from the material introduction unit 247, and is transported through the connecting unit 246 and the central unit 245 to the communication hole 256 formed in the barrel 250. For example, there are two first grooves 244.

[0029] The number of the first grooves 244 is not particularly limited. Although not shown in the diagram, there may be three or more first grooves 244, or there may be only one.

[0030] As shown in Figure 3, the barrel 250 is located below the flat screw 240. The barrel 250 has an opposing surface 252 that faces the groove-forming surface 242 of the flat screw 240. A communication hole 256 that communicates with the first groove 244 is formed in the center of the opposing surface 252. Here, Figure 5 is a schematic plan view of the barrel 250.

[0031] As shown in Figure 5, a second groove 254 and a communication hole 256 are formed on the opposing surface 252 of the barrel 250. Multiple second grooves 254 are formed. In the illustrated example, six second grooves 254 are formed, but the number of second grooves 254 is not particularly limited. Multiple second grooves 254 are formed around the communication hole 256 when viewed from the Z-axis direction. One end of the second groove 254 is connected to the communication hole 256 and extends in a spiral shape from the communication hole 256 toward the outer circumference of the barrel 250. The second groove 254 has the function of guiding the plasticized molding material to the communication hole 256.

[0032] The shape of the second groove 254 is not particularly limited and may be, for example, straight. Furthermore, one end of the second groove 254 does not have to be connected to the communication hole 256. Moreover, the second groove 254 does not have to be formed on the opposing surface 252. However, considering the efficient guidance of the plasticized molding material into the communication hole 256, the second groove 254 is formed on the opposing surface 252. It is preferable that this is the case.

[0033] The heater 258 is located in the barrel 250, as shown in Figure 3. The heater 258 heats the material supplied between the flat screw 240 and the barrel 250. The heater 258 is controlled by the control unit 290. The plasticizing unit 230 uses the flat screw 240, barrel 250, and heater 258 to heat and transport the molding material toward the communication hole 256, thereby generating plasticized molding material, which is then discharged from the communication hole 256. Viewed from the Z-axis direction, the shape of the heater 258 may be ring-shaped.

[0034] The heater 258 does not necessarily have to be provided on the barrel 250; for example, it may be provided on the flat screw 240. Also, although not shown in the figures, the plasticizing section 230 may use an in-line screw that is long in the direction of the rotation axis instead of the flat screw 240 to plasticize the molding material.

[0035] The nozzle 260 is located below the barrel 250. The nozzle 260 has a nozzle hole 262. The nozzle hole 262 communicates with a communication hole 256. The molding material is supplied to the nozzle hole 262 from the communication hole 256. The nozzle 260 extrudes the plasticized molding material from the nozzle hole 262 toward the stage 280. As a result, the molding unit 210 creates a molded object on the stage 280.

[0036] As shown in Figure 2, the cutting unit 270 rotates a first rotary tool 272 attached to the tip of the stage 280 to cut the molded object on the stage 280. For example, the cutting unit 270 cuts the molded object to create a molded product 10 having a cavity 12. The first rotary tool 272 is rotatable about an axis parallel to the Z-axis. For example, a flat end mill or a ball end mill can be used as the first rotary tool 272. The control unit 290 controls the cutting position by controlling the position change unit 282 to change the relative position between the first rotary tool 272 and the molded object formed on the stage 280.

[0037] The molded product 10 is placed on the stage 280. In the illustrated example, the molded product 10 is directly mounted on the stage 280. Although not shown in the illustration, the molded product 10 may also be mounted on the stage 280 via a predetermined plate.

[0038] The positioning unit 282 supports the stage 280. In the illustrated example, the positioning unit 282 is configured as a three-axis positioner that moves the stage 280 along three mutually orthogonal axes relative to the molding unit 210 and the cutting unit 270.

[0039] The position change unit 282 may move the molding unit 210 and the cutting unit 270 relative to the stage 280 without moving the stage 280. Alternatively, the position change unit 282 may move both the stage 280 and the molding unit 210 and cutting unit 270. For example, the position change unit 282 may move the stage 280 in the X-axis and Y-axis directions, and move the molding unit 210 and cutting unit 270 in the Z-axis direction.

[0040] The position-changing unit 282 may have the function of tilting the stage 280 with respect to the horizontal plane. The position-changing unit 282 may also have the function of tilting the nozzle 260 and the first rotating tool 272 with respect to the horizontal plane.

[0041] The control unit 290 is composed of, for example, a computer having a processor, main memory, and an input / output interface for inputting and outputting signals to and from the outside. For example, the 290 controls the molding unit 210, the cutting unit 270, and the position changing unit 282 by having the processor execute a program loaded into the main memory. Note that the control unit 290 may be composed of a combination of multiple circuits rather than a computer.

[0042] Here, Figure 6 is a schematic cross-sectional view showing the manufacturing process of the molded product 10 in the three-dimensional molding apparatus 200.

[0043] As shown in Figure 6, the control unit 290 maintains the distance between the stage 280 and the nozzle 260, and while changing the position of the nozzle 260 relative to the stage 280 in a direction along the upper surface of the stage 280, it causes the plasticized molding material to be ejected from the nozzle 260. The molding material ejected from the nozzle 260 is continuously deposited on the stage 280 in the direction of movement of the nozzle 260, forming layer 14.

[0044] The control unit 290 repeatedly scans the nozzle 260 to form multiple layers 14. Specifically, after forming one layer 14, the control unit 290 moves the position of the nozzle 260 relative to the stage 280 upward. Then, by stacking more layers 14 on top of the layers 14 that have been formed so far, it fabricates a molded product 10 consisting of multiple layers 14. The molded product 10 is a laminate consisting of multiple layers 14.

[0045] The control unit 290 may temporarily interrupt the ejection of the molding material from the nozzle 260, for example, when moving the nozzle 260 upward after depositing one layer 14, or when creating discontinuous passes. In this case, the control unit 290 controls a butterfly valve (not shown) provided in the nozzle hole 262 to stop the ejection of the molding material from the nozzle 260. After changing the position of the nozzle 260, the control unit 290 opens the butterfly valve to restart the ejection of the molding material, thereby resuming the deposition of the molding material from the changed position of the nozzle 260.

[0046] 1.3. Injection molding equipment Figure 7 is a schematic side view of the injection molding apparatus 300 of the molded product recycling system 100. The injection molding apparatus 300 uses, for example, a molded product 10 created by the three-dimensional molding apparatus 200 as part of the movable mold 342.

[0047] As shown in Figure 7, the injection molding apparatus 300 includes, for example, a material supply unit 310, an injection unit 320, a mold unit 330, a mold clamping unit 360, and a control unit 370.

[0048] The material supply unit 310 supplies raw materials to the injection unit 320. The material supply unit 310 is composed of, for example, a hopper. The material supplied from the material supply unit 310 is in the form of, for example, pellets or powder. The material supplied from the material supply unit 310 is, for example, acrylonitrile butadiene styrene (ABS) resin, polyphenylene sulfide (PPS), or materials to which metal particles have been added.

[0049] The injection unit 320 plasticizes the material supplied from the material supply unit 310 to form a plasticized material. The injection unit 320 then injects the plasticized material toward the mold unit 330.

[0050] A cavity corresponding to the shape of the molded product is formed in the mold section 330. The material injected from the injection section 320 flows into the cavity. The plasticized material is then cooled and solidified, and the molded product is produced.

[0051] The clamping section 360 opens and closes the mold of the mold section 330. The clamping section 360 holds the plasticized material After the material has cooled and solidified, the mold of the mold section 330 is opened. This allows the molded product to be discharged to the outside.

[0052] The control unit 370 is composed of, for example, a computer having a processor, main memory, and an input / output interface for inputting and outputting signals to and from the outside. The control unit 370 performs various functions, for example, by having the processor execute a program loaded into the main memory. Specifically, the control unit 370 controls the injection unit 320 and the clamping unit 360. Note that the control unit 370 may be composed of a combination of multiple circuits instead of a computer.

[0053] Figure 8 is a schematic cross-sectional view of the injection molding apparatus 300 taken along line VIII-VIII in Figure 7. As shown in Figure 8, the injection unit 320 includes, for example, a plasticizing unit 322, an injection mechanism 324, and a nozzle 328.

[0054] The plasticizing unit 322 is configured to plasticize the material supplied from the material supply unit 310, turning it into a fluid paste-like material that is then guided to the injection mechanism 324. The configuration and function of the plasticizing unit 322 are basically the same as those of the plasticizing unit 230 of the three-dimensional molding apparatus 200 described above. That is, the plasticizing unit 322 includes a drive motor, a flat screw, a barrel, and a heater.

[0055] The injection mechanism 324 includes, for example, a cylinder 325, a plunger 326, and a plunger drive unit 327. The cylinder 325 is a substantially cylindrical member connected to the communication hole 323 of the plasticizing section 322. The plunger 326 moves inside the cylinder 325. The plunger 326 is driven by the plunger drive unit 327, which is composed of a motor, gears, etc. The plunger drive unit 327 is controlled by the control unit 370. The cylinder 325 may also be connected to a flow path downstream of the communication hole 323.

[0056] The injection mechanism 324 performs metering and injection operations by sliding the plunger 326 within the cylinder 325. The metering operation refers to the operation of moving the plunger 326 away from the communication hole 323 in the X-axis direction, thereby guiding the plasticized material located in the communication hole 323 into the cylinder 325 and metering it within the cylinder 325. The injection operation refers to the operation of moving the plunger 326 closer to the communication hole 323 in the X-axis direction, thereby injecting the plasticized material in the cylinder 325 into the mold section 330 via the nozzle 328.

[0057] The nozzle 328 has a nozzle hole 329 that communicates with the communication hole 323. The nozzle 328 injects the material supplied from the plasticizing section 322 toward the mold 340 of the mold section 330. Specifically, as the metering and injection operations described above are performed, the material metered in the cylinder 325 is sent from the injection mechanism 324 through the communication hole 323 to the nozzle hole 329. The material is then injected from the nozzle hole 329 into the mold 340.

[0058] The mold section 330 includes a mold 340 and an extrusion mechanism 350. Material sent to the nozzle hole 329 is injected from the nozzle hole 329 into the cavity 12 of the mold 340. Specifically, the mold 340 has a movable mold 342 and a fixed mold 346 facing each other, with a cavity 12 between the movable mold 342 and the fixed mold 346. The cavity 12 is a space corresponding to the shape of the molded product formed by the injection molding apparatus 300. Here, Figure 9 is a schematic exploded perspective view showing the movable mold 342 of the mold 340.

[0059] The movable mold 342 of the molding die 340 has, for example, a molded product 10 and a master mold 343, as shown in Figure 9. The molded product 10 is manufactured by the three-dimensional molding apparatus 200 described above. The molded product 10 is a core. The molded product 10 has a first part 16 that constitutes a cavity 12 and a second part 18 that does not constitute a cavity 12. The first part 16 is the surface of the molded product 10 that defines the cavity 12. A test piece 20 is connected to the molded product 10. The test piece 20 is provided integrally with the molded product 10. The test piece 20 is, for example, a test piece for tensile testing, compression testing, etc. For convenience, the illustration of the test piece 20 is omitted in Figure 2.

[0060] The movable mold 342 of the molding die 340 is formed by fitting the molded product 10 into a recess 344 formed in the master mold 343, as shown in Figure 9. Before fitting the molded product 10 into the recess 344, the test piece 20 is broken off from the molded product 10. The material of the master mold 343 is, for example, metal. Although not shown in the figures, the test piece 20 may be provided separately from the molded product 10. In this case, the step of breaking off the test piece 20 from the molded product 10 can be omitted.

[0061] As shown in Figure 8, the extrusion mechanism 350 is provided on the movable mold 342. The extrusion mechanism 350 releases the molded product formed by the injection molding apparatus 300 from the mold 340. The extrusion mechanism 350 includes, for example, an ejector pin 351, a support plate 352, a support rod 353, a spring 354, an extrusion plate 355, and a thrust bearing 356.

[0062] The ejector pin 351 is a rod-shaped member used to push out the molded product formed in the cavity 12. The ejector pin 351 is positioned to pass through the movable mold 342 and reach the cavity 12.

[0063] The support plate 352 is a plate member that supports the ejector pin 351. The ejector pin 351 is fixed to the support plate 352. The support rod 353 is fixed to the support plate 352. The support rod 353 is inserted through a through hole formed in the movable type 342.

[0064] The spring 354 is positioned in the space between the movable mold 342 and the support plate 352. The spring 354 is inserted into the support rod 353. During molding, the spring 354 biases the support plate 352 such that the head of the ejector pin 351 forms part of the wall surface of the cavity 12.

[0065] The extruded plate 355 is fixed to the support plate 352. The thrust bearing 356 is attached to the extruded plate 355. The thrust bearing 356 is designed so that the head of the ball screw portion 364 does not damage the extruded plate 355. Alternatively, a thrust sliding bearing or the like may be used instead of the thrust bearing 356.

[0066] The mold clamping section 360 includes, for example, a mold drive section 362 and a ball screw section 364. The mold drive section 362 is composed of, for example, a motor, gears, etc. The mold drive section 362 is connected to the movable mold 342 via the ball screw section 364. The mold drive section 362 is controlled by the control section 370. The ball screw section 364 transmits power from the drive of the mold drive section 362 to the movable mold 342. The mold clamping section 360 opens and closes the molding mold 340 by moving the movable mold 342 with the help of the mold drive section 362 and the ball screw section 364.

[0067] 1.4. Cutting equipment Figure 10 is a schematic perspective view of the cutting device 400 of the molded product recycling system 100. The cutting device 400 cuts the molded product 10, which was used as part of the movable mold 342 in the injection molding machine 300, to generate recycled material that is reused as a molding material for the three-dimensional molding machine 200.

[0068] As shown in Figure 10, the cutting apparatus 400 includes, for example, a cutting unit 410, a stage 420, a position changing unit 430, and a control unit 440.

[0069] The cutting device 400 rotates the second rotary tool 412 of the cutting unit 410 and drives the position change unit 430 to change the relative position between the second rotary tool 412 and the stage 420. Then, as shown in Figure 11, the cutting unit 410 cuts the molded product 10 formed on the stage 420. In this way, the cutting unit 410 generates recycled material 30. The recycled material 30 is the cutting chips of the molded product 10. In the illustrated example, the shape of the recycled material 30 is pellet-like. Figure 11 is a diagram illustrating the cutting of the molded product 10 by the second rotary tool 412 of the cutting device 400.

[0070] Here, Figure 12 is a schematic bottom view of the second rotating tool 412. Figure 13 is a schematic side view of the second rotating tool 412.

[0071] The second rotary tool 412 has, for example, multiple blades 414, as shown in Figure 12. In the illustrated example, the second rotary tool 412 has three blades 414. The second rotary tool 412 has a rafting structure in which irregularities are formed on the surface of the blades 414, as shown in Figure 13. In the illustrated example, the second rotary tool 412 is a three-blade rafting end mill. The first rotary tool 272 of the three-dimensional molding apparatus 200 described above may have the same shape as the second rotary tool 412.

[0072] As shown in Figure 10, the molded product 10 is placed on the stage 420. In the illustrated example, the molded product 10 is directly mounted on the stage 420. The stage 420 has a magnetic section 422. In the illustrated example, the molded product 10 is mounted on the magnetic section 422. The magnetic section 422 is made of, for example, a neodymium magnet. If the molded product 10 contains metal particles, the magnetic section 422 recovers the metal particles of the recycled material 30 generated from the molded product 10 by magnetic force.

[0073] The configuration and function of the position change unit 430 are basically the same as those of the position change unit 282 of the three-dimensional molding apparatus 200 described above. The configuration and function of the control unit 440 are basically the same as those of the control unit 290 of the three-dimensional molding apparatus 200 described above.

[0074] 2. Manufacturing method of molded products 2.1. Overall Flow Figure 14 is a flowchart illustrating the manufacturing method of the molded product according to this embodiment.

[0075] As shown in Figure 14, the method for manufacturing a molded product according to this embodiment includes: a first step S1 in which a molding material containing a thermoplastic resin is extruded to form a molded body, and a first molded product is formed by cutting the molded body with a first rotary tool 272; a second step S2 in which recycled material is generated by cutting the first molded product with a second rotary tool 412; and a third step S3 in which a second molded product is formed by extruding the plasticized recycled material. Each step will be described below.

[0076] 2.2. First step In the first step, a three-dimensional molding device 200 of the molded product recycling system 100 shown in Figure 2 is used to extrude molding material and create a molded object. Then, the first molded product is formed by cutting the molded object with the first rotating tool 272 of the three-dimensional molding device 200. Specifically, the control unit 290 of the three-dimensional molding device 200 controls the drive unit that rotates the first rotating tool 272, thereby rotating the first rotating tool 272. Furthermore, the control unit 290 controls the position change unit 282, The first rotating tool 272 is moved relative to the stage 280, and the first rotating tool 272 is brought into contact with the printed object to cut the object.

[0077] The molding material includes thermoplastic resins. Examples of thermoplastic resins include general-purpose engineering plastics and super engineering plastics.

[0078] Examples of general-purpose engineering plastics include ABS resin, polypropylene (PP), polyethylene (PE), polyacetal (POM), polyvinyl chloride (PVC), polyamide (PA), polylactic acid (PLA), polycarbonate (PC), modified polyphenylene ether, polybutylene terephthalate, and polyethylene terephthalate.

[0079] Examples of super engineering plastics include polysulfone (PSU), polyethersulfone (PES), PPS, polyarylate (PAR), polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), and polyetheretherketone (PEEK).

[0080] The molding material may contain metal particles. The metal particles contained in the molding material are, for example, amorphous metal particles mainly composed of iron (Fe). That is, the amorphous metal particles contain 70% by mass or more of iron. The amorphous metal particles may also have cobalt (Co), nickel (Ni), silicon (Si), boron (B), chromium (Cr), tungsten (W), niobium (Nb), tantalum (Ta), titanium (Ti), zirconium (Zr), hafnium (Hf), etc., added to the main component.

[0081] The amorphous metal particles contained in the molding material are, for example, spherical in shape. These amorphous metal particles are formed, for example, by atomization. Spherical amorphous metal particles can be obtained by atomization.

[0082] The content of amorphous metal particles in the molding material is, for example, 20% by volume or more and 40% by volume or less, preferably 30% by volume or more and 40% by volume or less, and more preferably 35% by volume or more and 40% by volume or less.

[0083] Amorphous metal particles contained in the molding material may be coated with a compatibilizer. The compatibilizer coated on the amorphous metal particles is, for example, a silane coupling agent. The material of the silane coupling agent is, for example, 3-mercaptopropyltrimethoxysilane.

[0084] 2.3. Second process In the second step, recycled material is generated by cutting the first molded product with a second rotary tool 412 using the cutting device 400 of the molded product recycling system 100 shown in Figure 10. In the second step, for example, the first molded product used as part of the movable mold 342 of the injection molding device 300 of the molded product recycling system 100 shown in Figure 8 is cut.

[0085] In the second step, the first molded product is cut under a first condition where the movement speed of the second rotating tool 412 is faster than the movement speed of the first rotating tool 272 in the first step. Specifically, the control unit 440 of the cutting apparatus 400 shown in Figure 10 controls the position change unit 430 so that the movement speed of the second rotating tool 412 relative to the stage 420 is faster than the movement speed of the first rotating tool 272 relative to the stage 280 in the first step, and the first molded product is cut. The movement speed of the second rotating tool 412 in the second step is, for example, 1200 mm / min or more and 10800 mm / min or less.

[0086] In the second step, the first molded product is cut under a second condition in which the rotational speed of the second rotating tool 412 is slower than the rotational speed of the first rotating tool 272 in the first step. Specifically, the control unit 440 controls the drive unit that rotates the second rotating tool 412 so that the rotational speed of the second rotating tool 412 is slower than the rotational speed of the first rotating tool 272 in the first step, thereby rotating the second rotating tool 412. The rotational speed of the second rotating tool 412 is, for example, between 100 rpm and 900 rpm.

[0087] In the second step, the first molded product is cut under at least one of the first and second conditions. That is, in the second step, the first molded product may be cut under both the first and second conditions, or it may be cut under the second condition without using the first condition, or it may be cut under the first condition without using the second condition.

[0088] In the second step, for example, the ratio of the travel speed (mm / min) of the second rotating tool 412 to the rotational speed (rpm) of the second rotating tool 412 is 12 or more. This ratio is, for example, 100 or less.

[0089] In the second step, the second portion 18 of the molded product 10 that does not constitute the cavity 12 is cut to generate recycled material 30. Specifically, the control unit 440 controls the position change unit 430 to bring the second rotating tool 412 into contact with the second portion 18. For example, the first portion 16 that defines the cavity 12 is cut by about 1 mm, and recycled material is generated from the remaining second portion 18.

[0090] If the molding material contains metal particles such as iron, in the second step, the cutting chips from the first molded product are collected by the magnetic force of the magnet unit 422. This suppresses the scattering of cutting chips during cutting.

[0091] In the second step, instead of the cutting device 400, the cutting unit 270 of the three-dimensional molding device 200 may be used to cut the first molded product with the first rotary tool 272, thereby generating reusable material. In this case, the rotary tool used in the first step and the rotary tool used in the second step will be the same first rotary tool 272.

[0092] Alternatively, recycled material may be obtained by processing the cutting waste generated in the second step using a crusher or extruder.

[0093] 2.4. Third step In the third step, the recycled material generated in the second step is plasticized using the three-dimensional molding apparatus 200 shown in Figure 2. Then, the plasticized recycled material is extruded onto the stage 280 using the three-dimensional molding apparatus 200 to form a second molded product. The shape of the second molded product may be the same as or different from that of the first molded product. The material of the second molded product may be the same as or different from that of the first molded product.

[0094] In the third step, for example, the recycled material to which additives have been added is plasticized and then extruded. Examples of additives include plasticization accelerators and metal particles contained in the molding material from the first step. The amount of additives may be increased as the number of times the molded product is recycled increases.

[0095] In the third step, a test piece is fabricated, either integrally with the second molded product or as a separate component.

[0096] Through the above process, the molded product can be recycled. There is no particular limit to the number of times the molded product can be recycled.

[0097] 2.4. Effects The method for manufacturing a molded product includes a first step of forming a molded body by extruding a molding material containing a thermoplastic resin and then molding a first molded product by cutting the molded body with a first rotary tool 272; a second step of generating recycled material by cutting the first molded product with a second rotary tool 412; and a third step of molding a second molded product by extruding the plasticized recycled material. In the second step, the first molded product is cut under at least one of the following conditions: the moving speed of the second rotary tool 412 is faster than the moving speed of the first rotary tool 272 in the first step, and the rotational speed of the second rotary tool 412 is slower than the rotational speed of the first rotary tool 272 in the first step.

[0098] Therefore, in the manufacturing method for molded products, the possibility of the recycled material forming a spiral shape can be reduced, as shown in the experimental example described later. This reduces the possibility of bridging occurring due to interference between recycled materials when plasticizing them, and allows for stable plasticization of the recycled material.

[0099] In the method for manufacturing molded products, the second rotating tool 412 has a blade 414 with a rafting structure. Therefore, in the method for manufacturing molded products, it is possible to suppress the length of the recycled material from becoming too long in the longitudinal direction. If the blade of the second rotating tool does not have a rafting structure, the length of the recycled material will become too long, increasing the likelihood of bridging occurring when the recycled material is plasticized.

[0100] In the method for manufacturing molded products, in the second step, the ratio of the travel speed (mm / min) to the rotational speed (rpm) of the second rotating tool 412 is 12 or more. Therefore, in the method for manufacturing molded products, as shown in the experimental example described later, the possibility of the recycled material forming a spiral shape can be reduced.

[0101] In the method for manufacturing molded products, the molding material contains amorphous metal particles mainly composed of iron. Amorphous metals have a thermal conductivity lower than that of metals and higher than that of resins. Therefore, compared to the method using molding materials made of resin, the heat trapped in the molded product can be reduced, and the cooling time of the molded product can be shortened. Furthermore, compared to the method using molding materials made of metals, it is possible to mold products that are less prone to filling defects and warping.

[0102] In the method for manufacturing molded articles, the amorphous metal particles are spherical. Therefore, compared to the case where the amorphous metal particles are not spherical, this method allows for the molding of molded articles with a smaller difference in elastic modulus between the mutually orthogonal first and second directions.

[0103] Furthermore, it is possible to increase the likelihood that the size of amorphous metal particles in the first molded product and the size of amorphous metal particles in the second molded product using recycled materials will be the same. For example, if the amorphous metal particles are fibrous, they will be cut in the second process, and it is highly likely that the amorphous metal particles in the second molded product will be smaller than those in the first molded product.

[0104] In the method for manufacturing molded articles, at least one of the first molded article and the second molded article is at least a part of the mold 340 used in the injection molding apparatus 300. Therefore, in the method for manufacturing molded articles, at least a part of the mold 340 can be molded.

[0105] In the method for manufacturing molded products, the first molded product is at least a part of a mold 340 having a cavity 12, and in the second step, the second part 18 of the first molded product that does not constitute the cavity 12 is cut to generate recycled material. Therefore, in the method for manufacturing molded products, recycled material can be generated without using parts that are severely degraded by injection molding. The first part 16 that constitutes the cavity 12 of the first molded product is a plasticized high-temperature molding material. Because it comes into contact with the second part 18, it deteriorates more severely.

[0106] In the method for manufacturing molded products, the third step involves plasticizing the recycled material to which additives have been added, and then extruding it. Therefore, in this method for manufacturing molded products, the composition of the material constituting the second molded product can be made to be closer to the composition of the material constituting the first molded product.

[0107] In the method for manufacturing molded products, a test piece 20 is fabricated either integrally with the second molded product or as a separate part. Therefore, by testing the test piece 20, it is possible to investigate whether the physical properties of the second molded product deviate from those of the first molded product.

[0108] In the method for manufacturing molded products, the molding material contains metal particles, and in the second step, the cutting chips from the first molded product are collected using magnetism. Therefore, the scattering of cutting chips during cutting can be suppressed.

[0109] 3. Experimental Examples 3.1. Experimental Conditions Figure 15 is a perspective view illustrating an experimental example. Figure 16 is a side view illustrating an experimental example. For convenience, the rotary tool T is simplified in Figures 15 and 16. As shown in Figures 15 and 16, the workpiece W was cut with the rotary tool T, and the shape of the cutting chips was investigated. The material of the workpiece W was PPS with metal particles added. The metal particle content was 40% by volume. As the metal particles, "KUAMET" atomized powder manufactured by Epson Atomics Corporation was used.

[0110] The rotary tool T was rotated around a rotation axis C parallel to the Z axis, and moved in the +Y axis relative to the workpiece W to cut the workpiece W. As shown in Figure 16, the depth of cut G in the Z axis direction of the rotary tool T relative to the workpiece W was set to 3 mm. Then, the rotary tool T was moved in the +X axis direction by a side step amount D, and then moved again in the +Y axis relative to the workpiece W to cut the workpiece W.

[0111] Figure 17 is a photograph of the external appearance of the rotary tool T. As shown in Figure 17, the rotary tool T has three cutting edges B. The rotary tool T is a three-edged rafting end mill. The diameter of the rotary tool T is 16 mm.

[0112] Figures 18 and 19 are tables showing the cutting conditions. As shown in Figures 18 and 19, the cutting conditions are numbered from Condition 1 to Condition 16. Figure 18 shows Conditions 1 to 8. Figure 19 shows Conditions 9 to 16.

[0113] In Figures 18 and 19, "rotational speed" is the rotational speed (rpm) of the rotary tool. "Travel speed" is the travel speed (mm / min) of the rotary tool T in the +Y axis direction relative to the workpiece W. "Peripheral speed" is the surface speed (m / min) due to the rotation of the rotary tool. "Work done / tooth" is the value obtained by dividing "travel speed" by "rotational speed" and the number of teeth, "3". "Ratio (travel speed / rotational speed)" is the value obtained by dividing "travel speed" by "rotational speed".

[0114] 3.2. Experimental Results Figure 20 is a photograph of the chips generated when the workpiece W was cut under conditions 1 to 6. Figure 21 is a photograph of the chips generated when the workpiece W was cut under conditions 7 to 12. The magnification of the photographs in Figures 20 and 21 is 20x. Although photographs of the chips for conditions 13 to 16 are not shown in Figures 20 and 21, the chips for conditions 13 to 16 had a similar shape to those for condition 12.

[0115] As shown in Figures 20 and 21, it was found that the smaller the ratio (moving speed / rotational speed), the more likely the cutting chips are to form a spiral shape. Under condition 12, where the ratio (moving speed / rotational speed) = 12, no spiral-shaped cutting chips were observed. This experiment showed that the spiral shape of cutting chips can be reduced by increasing the moving speed and, furthermore, by decreasing the rotational speed.

[0116] In conditions 12 through 16, where the ratio (movement speed / rotation speed) = 12, condition 16, which has the fastest movement speed, is preferable when considering productivity.

[0117] The embodiments and variations described above are examples only and are not limited thereto. For example, each embodiment and each variation can be combined as appropriate.

[0118] The present invention includes configurations substantially identical to those described in the embodiments, for example, configurations with the same function, method, and results, or configurations with the same purpose and effect. Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Finally, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0119] The following can be derived from the embodiments and modifications described above.

[0120] One embodiment of a method for manufacturing a mold is: A first step involves extruding a molding material containing a thermoplastic resin to form a molded body, and then cutting the molded body with a first rotary tool to form a first molded product. A second step involves generating recycled material by cutting the first molded product with a second rotating tool, A third step involves extruding the plasticized recycled material to form a second molded product, Includes, In the second step, the first molded product is cut under at least one of the following conditions: the moving speed of the second rotating tool is faster than the moving speed of the first rotating tool in the first step, and the rotational speed of the second rotating tool is slower than the rotational speed of the first rotating tool in the first step.

[0121] This method of manufacturing molded products can reduce the likelihood of recycled materials forming a spiral shape.

[0122] In one embodiment of a method for manufacturing a mold, The second rotary tool may have a blade with a rafting structure.

[0123] This method for manufacturing molded products makes it possible to prevent the longitudinal length of the recycled material from becoming too long.

[0124] In one embodiment of a method for manufacturing a mold, In the second step, the ratio of the travel speed (mm / min) to the rotational speed (rpm) of the second rotating tool may be 12 or more.

[0125] This method of manufacturing molded products can reduce the likelihood of recycled materials forming a spiral shape.

[0126] In one embodiment of a method for manufacturing a mold, The molding material may also contain amorphous metal particles, with iron as the main component.

[0127] According to this method of manufacturing molded products, it is possible to reduce the heat trapped in the molded product, shorten the cooling time, and molded products that are less prone to filling defects and warping.

[0128] In one embodiment of a method for manufacturing a mold, The amorphous metal particles may be spherical in shape.

[0129] According to this method for manufacturing molded articles, it is possible to mold articles in which the difference in elastic modulus is small in a first direction and a second direction that are orthogonal to each other.

[0130] In one embodiment of a method for manufacturing a mold, At least one of the first molded product and the second molded product may be at least a part of a mold used in an injection molding apparatus.

[0131] According to this method for manufacturing molded articles, at least a portion of the mold can be molded.

[0132] In one embodiment of a method for manufacturing a mold, The first molded product is at least a part of a mold having a cavity, In the second step, the portion of the first molded product that does not constitute the cavity may be cut to generate the recycled material.

[0133] This method of manufacturing molded products allows for the creation of reusable materials without using parts that are severely degraded by injection molding.

[0134] In one embodiment of a method for manufacturing a mold, In the third step, the recycled material to which the additive has been added may be plasticized and then extruded.

[0135] According to this method for manufacturing molded products, the composition of the material constituting the second molded product can be made to be closer to the composition of the material constituting the first molded product.

[0136] In one embodiment of a method for manufacturing a mold, In the third step, a test piece may be formed either integrally with or separately from the second molded product.

[0137] According to this method for manufacturing molded products, by testing test pieces, it is possible to investigate whether the physical properties of the second molded product deviate from those of the first molded product.

[0138] In one embodiment of a method for manufacturing a mold, The aforementioned molding material contains metal particles, In the second step, the cutting chips of the first molded product may be collected by magnetic force.

[0139] This method of manufacturing molded products makes it possible to suppress the scattering of cutting chips during cutting. [Explanation of symbols]

[0140] 10…Molded product, 12…Cavity, 14…Layer, 16…First part, 18…Second part, 20…Test piece, 30…Recycled material, 100…Molded product recycling system, 200…Three-dimensional molding device, 210…Molding unit, 220…Material supply unit, 230…Plasticizing unit, 232…Screw case, 234…Drive motor, 236…Shaft, 240…Flat screw, 241…Top surface, 242…Groove forming surface, 243…Side surface, 244…First groove, 245…Center part, 246…Connection part, 247…Material introduction part, 250…Barrel, 252…Opposite surface, 254…Second groove 256...Communication hole, 258...Heater, 260...Nozzle, 262...Nozzle hole, 270...Cutting unit, 272...First rotating tool, 280...Stage, 282...Position change unit, 290...Control unit, 300...Injection molding apparatus, 310...Material supply unit, 320...Injection unit, 322...Plasticizing unit, 323...Communication hole, 324...Injection mechanism, 325...Cylinder, 326...Plunger, 327...Plunger drive unit, 328...Nozzle, 329...Nozzle hole, 330...Mold unit, 340... Molding mold, 342…Movable mold, 343…Master mold, 344…Recess, 346…Fixed mold, 350…Extrusion mechanism, 351…Ejector pin, 352…Support plate, 353…Support rod, 354…Spring, 355…Extrusion plate, 356…Thrust bearing, 360…Clamping section, 362…Mold drive section, 364…Ball screw section, 370…Control unit, 400…Cutting device, 410…Cutting unit, 412…Second rotating tool, 420…Stage, 422…Magnet section, 430…Position change section, 440…Control unit

Claims

1. A first step involves extruding a molding material containing a thermoplastic resin to form a molded body, and then cutting the molded body with a first rotary tool to form a first molded product. A second step involves generating recycled material by cutting the first molded product with a second rotating tool, A third step involves extruding the plasticized recycled material to form a second molded product, Includes, A method for manufacturing a molded product, wherein in the second step, the first molded product is cut under at least one of the following conditions: the moving speed of the second rotating tool is faster than the moving speed of the first rotating tool in the first step, and the rotational speed of the second rotating tool is slower than the rotational speed of the first rotating tool in the first step.

2. In claim 1, The aforementioned second rotating tool has a blade with a rafting structure, and is a method for manufacturing a molded product.

3. In claim 1 or 2, A method for manufacturing a molded product, wherein in the second step, the ratio of the moving speed (mm / min) to the rotational speed (rpm) of the second rotating tool is 12 or more.

4. In claim 1 or 2, The molding material includes amorphous metal particles mainly composed of iron, and the method for manufacturing a molded product.

5. In claim 4, A method for manufacturing a molded article, wherein the amorphous metal particles have a spherical shape.

6. In claim 1 or 2, A method for manufacturing a molded article, wherein at least one of the first molded article and the second molded article is at least a part of a mold used in an injection molding apparatus.

7. In claim 6, The first molded product is at least a part of a mold having a cavity, A method for manufacturing a molded product, comprising the second step of cutting away the portion of the first molded product that does not constitute the cavity to generate the recycled material.

8. In claim 1 or 2, A method for manufacturing a molded product, wherein the third step involves plasticizing the recycled material to which additives have been added and then extruding it.

9. In claim 1 or 2, A method for manufacturing a molded product, wherein the third step involves forming a test piece that is integral to or separate from the second molded product.

10. In claim 1 or 2, The aforementioned molding material contains metal particles, A method for manufacturing a molded product, wherein the second step involves collecting the cutting chips of the first molded product using magnetic force.

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