Material delivery device, three-dimensional modeling device, and injection molding device

Abstract

To detect a pressure of a plasticized material in a desired place in a passage.SOLUTION: A material send-out device comprises: a plasticization section that has a screw, and plasticizes a material by a rotation of the screw to produce a plasticized material; a passage in which the plasticized material flows; a nozzle that communicates with the passage and has a nozzle opening for sending out the plasticized material to the outside; a cylinder that is connected to the passage; a rod that is inserted into the cylinder; and a first pressure detecting section that detects via the rod a pressure of the plasticized material in the passage. The rod has in a longitudinal direction of the rod a rod end face facing the passage and a transmission section on an opposite side to the rod end face, and transfers force due to a pressure received at the rod end face to the first pressure detecting section via the transmission section.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a material delivery apparatus, a three-dimensional modeling apparatus, and an injection molding apparatus. [Background technology]

[0002] Regarding a material delivery device that plasticizes a material and delivers it to the outside, Patent Document 1 discloses a technique in which the pressure of an injection resin that is injected into a mold by a plunger is detected by a pressure detection means. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 1994-198689 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a device such as that described in Patent Document 1, by controlling a mechanism such as a plunger based on the detected pressure, it is possible to, for example, prevent an excess or shortage of material being sent out from the device and prevent defects in products formed from the sent out material. In this case, in order to control the mechanism based on pressure with higher accuracy, it is preferable to detect the pressure of the resin in a flow path or the like close to the mechanism. However, for example, when a heat source is provided close to the part where pressure is to be detected, or when space for installing a pressure detection means cannot be secured close to the part, it may not be possible to detect the pressure in that part. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided a material delivery device. The material delivery device includes a plasticizing section having a screw and plasticizing a material by rotation of the screw to generate a plasticized material, a flow path through which the plasticized material flows, a nozzle communicating with the flow path and having a nozzle opening for delivering the plasticized material to the outside, a cylinder connected to the flow path, a rod inserted into the cylinder, and a first pressure detection section detecting the pressure of the plasticized material in the flow path via the rod. The rod has a rod end face facing the flow path in the longitudinal direction of the rod, and a transmission section farther from the flow path than the rod end face, and transmits the force due to the pressure received at the rod end face to the first pressure detection section via the transmission section.

[0006] According to a second aspect of the present disclosure, there is provided a three-dimensional modeling apparatus comprising: the material delivery device of the above aspect, a stage for depositing the plasticized material delivered from the nozzle, a control unit for controlling the material delivery device, and a delivery amount adjustment unit disposed in the flow path upstream of a connection between the flow path and the cylinder for adjusting a flow rate of the plasticized material delivered from the nozzle opening.

[0007] According to a third aspect of the present disclosure, there is provided an injection molding apparatus comprising the material delivery device of the above aspect and a control unit for controlling the material delivery device, wherein the nozzle delivers the plasticized material to a mold. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a schematic perspective view showing the configuration of a groove forming surface side of a screw. [Diagram 3] FIG. 2 is a diagram showing the configuration of the side of the barrel facing the screw. [Figure 4] FIG. 2 is a diagram showing a schematic configuration of a pressure detection unit in the first embodiment. [Diagram 5] FIG. 5 is a diagram showing a VV cross section in FIG. [Figure 6] 13A and 13B are diagrams illustrating an example of transmission of detection torque in another embodiment. [Figure 7] FIG. 13 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a second embodiment. [Figure 8] FIG. 13 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a third embodiment. [Figure 9] FIG. 11 is a perspective view showing a pressure detection unit according to a third embodiment. [Figure 10] 9 is a cross-sectional view showing the XX section in FIG. 8. [Figure 11] 13A to 13C are diagrams illustrating the operation of a detection unit in the third embodiment. [Figure 12] FIG. 13 is a diagram showing a schematic configuration of an injection molding device in a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A. First embodiment: FIG. 1 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus 100 according to the present embodiment. In FIG. 1, arrows are shown along the X, Y, and Z directions, which are orthogonal to each other. The X, Y, and Z directions are directions along the X, Y, and Z axes, which are three spatial axes that are orthogonal to each other, and each direction includes both a direction on one side along the X, Y, and Z axes and an opposite direction. The X and Y axes are axes along a horizontal plane, and the Z axis is an axis along a vertical line. In other figures, arrows along the X, Y, and Z directions are also shown as appropriate. The X, Y, and Z directions in FIG. 1 and the X, Y, and Z directions in other figures represent the same directions. In the following description, when specifying a direction, the positive direction indicated by the arrow is represented as "+" and the opposite negative direction is represented as "-", and positive and negative signs are used in combination to indicate the direction.

[0010] The three-dimensional modeling apparatus 100 in this embodiment includes a material delivery device 150, a stage 300, a position change unit 400, and a control unit 500.

[0011] The control unit 500 controls the overall operation of the three-dimensional printing apparatus 100 and executes a printing process for printing a three-dimensional object. The control unit 500 is configured by a computer having one or more processors and a main storage device. The control unit 500 performs various functions by the processor executing a program loaded into the main storage device. Note that some of the functions of the control unit 500 may be realized by a hardware circuit. In the printing process executed by the control unit 500, the material delivery device 150 and the position change unit 400 are controlled according to printing data of the three-dimensional object.

[0012] The material delivery device 150 delivers the plasticized material, which is obtained by melting a solid material and turning it into a paste, to the outside under the control of the control unit 500. In this embodiment, the material delivery device 150 discharges the plasticized material onto a modeling stage 300 that serves as a base for a three-dimensional object. The material delivery device 150 includes a material supply unit 20 that is a supply source of the material before it is converted into the plasticized material, a plasticizing unit 30 that plasticizes the material by rotating a screw 40 to generate the plasticized material, a flow path 66 through which the generated plasticized material flows, a nozzle 61 that communicates with the flow path 66 and delivers the plasticized material to the outside, and a pressure detection unit 200 that is connected to the flow path 66 and detects the pressure of the plasticized material in the flow path 66. Furthermore, in this embodiment, a delivery amount adjustment unit 70 is arranged in the flow path 66, and a suction and discharge unit 75 is connected to it.

[0013] The material supply unit 20 contains materials in the form of pellets, powder, etc. In this embodiment, ABS resin formed into pellets is used as the material. The material supply unit 20 in this embodiment is configured by a hopper. A supply path 22 that connects the material supply unit 20 and the plasticizing unit 30 is provided below the material supply unit 20. The material supply unit 20 supplies the material to the plasticizing unit 30 via the supply path 22.

[0014] The plasticizing section 30 includes a screw case 31, a drive motor 32, a screw 40, a barrel 50, and a plasticizing heater 58. The plasticizing section 30 plasticizes at least a part of the material supplied from the material supplying section 20 by the rotation of the screw 40, and generates a paste-like plasticized material having fluidity. The plasticizing section 30 then supplies the generated plasticized material to the nozzle 61 through a flow path 66 provided between the screw 40 and the nozzle 61. "Plasticization" is a concept that includes melting, and is a change from a solid to a state having fluidity. Specifically, in the case of a material in which a glass transition occurs, plasticization is a temperature of the material that is raised to or above the glass transition point. In the case of a material in which a glass transition does not occur, plasticization is a temperature of the material that is raised to or above the melting point. The screw 40 of this embodiment is a so-called flat screw, and is sometimes called a "scroll".

[0015] The screw case 31 is a housing for housing the screw 40. A barrel 50 is fixed to the lower surface of the screw case 31, and the screw 40 is housed in a space surrounded by the screw case 31 and the barrel 50. The screw 40 has a groove forming surface 42 on which a groove 45 is formed, on a surface facing the barrel 50. A drive motor 32 is fixed to the upper surface of the screw case 31. The rotating shaft of the drive motor 32 is connected to the upper surface 41 side of the screw 40. Note that the drive motor 32 does not have to be directly connected to the screw 40, and for example, the screw 40 and the drive motor 32 may be connected via a reducer. The drive motor 32 is driven under the control of the control unit 500.

[0016] The barrel 50 is disposed below the screw 40. The barrel 50 has a screw-facing surface 52 that faces the groove-forming surface 42 of the screw 40. The barrel 50 is provided with a communication hole 56 on the central axis AX of the screw 40. In this embodiment, the communication hole 56 forms a part of the above-mentioned flow path 66. More specifically, the flow path 66 is formed by the communication hole 56 and a supply flow path 67. The supply flow path 67 is a flow path that connects the communication hole 56 and the nozzle 61. In other embodiments, the supply flow path 67 may not be provided, and the communication hole 56 and the nozzle 61 may be directly connected.

[0017] In this embodiment, the plasticizing heater 58 is built into the barrel 50 at a position facing the groove 45 of the screw 40. The plasticizing heater 58 heats the material supplied between the screw 40 and the barrel 50. The temperature of the plasticizing heater 58 is controlled by the control unit 500.

[0018] FIG. 2 is a schematic perspective view showing the configuration of the groove forming surface 42 side of the screw 40. The central portion 47 of the groove forming surface 42 of the screw 40 is configured as a recess to which one end of the groove 45 is connected. The central portion 47 faces the communication hole 56 of the barrel 50 shown in FIG. 2. The central portion 47 intersects with the central axis AX. The groove 45 constitutes a so-called scroll groove. The groove 45 extends in a spiral shape from the central portion 47 to the outer periphery of the screw 40. The groove forming surface 42 is provided with a convex portion 46 that constitutes the side wall portion of the groove 45 and extends along each groove 45. The groove 45 continues to the material inlet 44 formed on the side surface 43 of the screw 40. The material inlet 44 is a portion that receives the material supplied through the supply path 22 of the material supply section 20. The material received by the material inlet 44 is supplied between the screw 40 and the barrel 50. 2, in this embodiment, three grooves 45 are formed, separated by convex rib portions 46. The number of grooves 45 is not limited to three, and may be one, or two or more. Groove 45 is not limited to a spiral shape, and may be a helical or involute curve shape, or may have a shape extending in an arc from a central portion 47 to the outer periphery.

[0019] FIG. 3 is a top view showing the configuration of the screw-opposed surface 52 side of the barrel 50. As described above, a communication hole 56 is formed in the center of the screw-opposed surface 52. A plurality of guide grooves 54 are formed around the communication hole 56 in the screw-opposed surface 52. One end of each guide groove 54 is connected to the communication hole 56, and extends in a spiral shape from the communication hole 56 toward the outer periphery of the screw-opposed surface 52. Each guide groove 54 has a function of guiding the plasticized material to the communication hole 56. Note that one end of the guide groove 54 does not have to be connected to the communication hole 56. Also, the barrel 50 does not have to have a guide groove 54 formed therein.

[0020] In this embodiment, the plasticization section 30 uses the above-mentioned screw 40, barrel 50 and plasticization heater 58 to heat the material supplied between the screw 40 and the barrel 50 while transporting it toward the flow path 66 to produce a plasticized material, and supplies the produced plasticized material to the nozzle 61 via the flow path 66.

[0021] As shown in FIG. 1, the nozzle 61 includes a nozzle flow path 65 and a tip surface 63 in which a nozzle opening 62 is provided. The nozzle flow path 65 is a flow path of the plasticized material formed in the nozzle 61, and is connected to the above-mentioned flow path 66. More specifically, in this embodiment, the nozzle flow path 65 is connected to the above-mentioned supply flow path 67. The tip surface 63 is a surface constituting the tip portion of the nozzle 61 protruding in the -Z direction toward the modeling surface 311. The nozzle opening 62 is a portion in which the flow path cross section of the nozzle flow path 65 is reduced, which is provided at the end of the nozzle flow path 65 on the side communicating with the atmosphere. The plasticized material generated by the plasticizing unit 30 is supplied to the nozzle 61 through the flow path 66 and discharged from the nozzle opening 62 through the nozzle flow path 65.

[0022] In this embodiment, a nozzle heater 68 is provided around the nozzle flow path 65. The nozzle heater 68 heats the nozzle 61 and heats the plasticized material in the nozzle flow path 65 under the control of the control unit 500. The control unit 500 can adjust the fluidity of the plasticized material in the nozzle flow path 65 by controlling the output of the nozzle heater 68. In this embodiment, the set temperature of the nozzle heater 68 is set to a temperature higher than the set temperature of the plasticizing heater 58 of the plasticizing unit 30 described above.

[0023] The delivery amount adjustment unit 70 adjusts the flow rate of the plasticized material delivered from the nozzle opening 62. The flow rate of the plasticized material delivered from the nozzle opening 62 to the outside is sometimes called the delivery amount. In this embodiment, the delivery amount adjustment unit 70 is configured by a butterfly valve that changes the opening degree of the flow path 66 by rotating in the flow path 66, and is arranged in the supply flow path 67 of the flow path 66. The delivery amount adjustment unit 70 is driven by a first drive unit 74 configured by a stepping motor or the like under the control of the control unit 500. The control unit 500 adjusts the opening degree of the flow path 66 by controlling the rotation angle of the butterfly valve using the first drive unit 74. In this way, the control unit 500 can adjust the flow rate of the plasticized material flowing from the plasticizing unit 30 to the nozzle 61 and adjust the delivery amount. The delivery amount adjustment unit 70 can also set the delivery amount to 0 by setting the opening degree of the flow path 66 to 0. In other words, the delivery rate adjusting unit 70 adjusts the delivery rate and also controls the on / off of the delivery of the plasticizing material.

[0024] The suction and discharge unit 75 is connected between the delivery amount adjustment unit 70 and the nozzle opening 62 in the flow path 66. The suction and discharge unit 75 performs a suction operation to suck the plasticized material in the flow path 66 and a discharge operation to push the sucked plasticized material toward the nozzle opening 62. In this embodiment, the suction and discharge unit 75 is configured with a plunger. In the above-mentioned suction operation, the suction and discharge unit 75 moves the plunger backward in a direction away from the flow path 66, and in the discharge operation, moves the plunger forward in a direction approaching the flow path 66. The suction and discharge unit 75 is driven by a second drive unit 76 under the control of the control unit 500. The second drive unit 76 is configured with, for example, a stepping motor or a rack and pinion mechanism that converts the rotational force of the stepping motor into translational motion of the plunger.

[0025] In this embodiment, the control unit 500 suppresses the tailing phenomenon in which the plasticized material hangs like a string from the nozzle opening 62 by executing a suction operation by the suction and discharge unit 75 when stopping the delivery of the plasticized material from the nozzle 61. In this case, the control unit 500 can more effectively suppress the tailing phenomenon by executing a suction operation after the delivery amount adjustment unit 70 sets the opening degree of the flow path 66 to 0. In addition, the suction and discharge unit 75 performs a discharge operation by the suction and discharge unit 75 when starting or resuming the delivery of the plasticized material from the nozzle 61, thereby improving the responsiveness of the delivery of the plasticized material from the nozzle 61. In this case, the control unit 500 can further improve the responsiveness of the delivery of the plasticized material by executing a suction operation before the delivery amount adjustment unit 70 sets the opening degree of the flow path 66 to be greater than 0.

[0026] The stage 300 is disposed at a position facing the tip surface 63 of the nozzle 61. The three-dimensional modeling device 100 delivers the plasticized material from the nozzle 61 toward the modeling surface 311 of the stage 300, and forms a three-dimensional object by stacking layers of the plasticized material.

[0027] The position changer 400 changes the relative position between the nozzle 61 and the stage 300 by changing the relative position between the material delivery device 150 and the stage 300. In this embodiment, the position changer 400 moves the stage 300 relative to the material delivery device 150. Note that the change in the relative position of the material delivery device 150 and the nozzle 61 with respect to the stage 300 may be simply referred to as the movement of the material delivery device 150 and the nozzle 61. That is, for example, the movement of the stage 300 in the +X direction can be rephrased as the movement of the material delivery device 150 and the nozzle 61 in the -X direction. The position changer 400 in this embodiment is composed of a three-axis positioner that moves the stage 300 in three axial directions, the X, Y, and Z directions, by the driving forces of three motors. Each motor is driven under the control of the control unit 500. The position changing unit 400 may not be configured to move the stage 300, but may be configured to move the material sending device 150 without moving the stage 300. The position changing unit 400 may also be configured to move both the stage 300 and the material sending device 150.

[0028] 4 is a diagram showing a schematic configuration of the pressure detection unit 200. The pressure detection unit 200 has a cylinder 210 connected to the flow path 66, a rod 220 inserted into the cylinder 210, and a first pressure detection section 240 that detects the pressure of the plasticized material in the flow path 66 via the rod 220. Furthermore, the pressure detection unit 200 in this embodiment has a force application member 230. The first pressure detection section 240 in this embodiment detects the pressure of the plasticized material in the flow path 66 via the rod 220 and the force application member 230.

[0029] The cylinder 210 in this embodiment has a cylindrical shape with its axial direction as the longitudinal direction. As shown in Figs. 1 and 4, the cylinder 210 is disposed such that its longitudinal direction is along the X direction. As shown in Fig. 1, the -X direction end of the cylinder 210 opens in the -X direction toward the flow path 66. The +X direction end of the cylinder 210 is located in the +X direction of the flow path 66. The flow path 66 communicates with the outside of the flow path 66 in the X direction via the cylinder 210.

[0030] In this embodiment, the cylinder 210 is connected to the flow path 66 downstream of the delivery amount adjustment unit 70. In other words, the delivery amount adjustment unit 70 is disposed in the flow path 66 upstream of the connection between the flow path 66 and the cylinder 210. The cylinder 210 is also connected to the flow path 66 downstream of the suction and discharge unit 75. In other embodiments, the cylinder 210 may be connected to the flow path 66 upstream of the suction and discharge unit 75, for example.

[0031] The rod 220 has an axial shape with its axial direction as the longitudinal direction. In this embodiment, the rod 220 is formed of tool steel. As shown in FIG. 1 and FIG. 4, the rod 220 is inserted into the cylinder 210 so that its longitudinal direction is along the X direction. The rod 220 has a rod end face 221 and a transmission part 222 that is farther from the flow path 66 than the rod end face 221 in the X direction. In this embodiment, the rod end face 221 is an end face of the rod 220 in the -X direction. As shown in FIG. 1, the rod end face 221 faces the flow path 66 in the cylinder 210. In this embodiment, the transmission part 222 is an end face of the rod 220 opposite to the rod end face 221 in the longitudinal direction, and is an end face of the rod 220 in the +X direction. As shown in FIG. 4, in this embodiment, the rod 220 has a coupling part 223 at an end in the +X direction that has a diameter larger than other parts of the rod 220 in the X direction. In this embodiment, the transmission part 222 is the +X direction end surface of the coupling part 223. As shown in Figures 1 and 4, the transmission part 222 contacts with the force application member 230 in the X direction at a position of the cylinder 210 in the +X direction.

[0032] The distance between the side surface of the rod 220 and the inner surface of the cylinder 210 is preferably, for example, 50 μm or less, more preferably 20 μm or less, and even more preferably 10 μm or less, from the viewpoint of suppressing leakage of the plasticized material in the flow path 66 to the outside through the gap between the rod 220 and the cylinder 210. Moreover, from the viewpoint of discharging gas generated from the plasticized material in the flow path 66 to the outside of the flow path 66 through the gap between the rod 220 and the cylinder 210, it is preferably, for example, 5 μm or more.

[0033] As shown in FIG. 1 and FIG. 4, the force applying member 230 is disposed between the rod 220 and the first pressure detection unit 240 in the X direction. The force applying member 230 has an axial shape with its axial direction as the longitudinal direction, and is disposed so that the longitudinal direction is along the X direction. In this embodiment, the force applying member 230 is formed of stainless steel. A force applying surface 231, which is an end face of the force applying member 230 in the +X direction, is in contact with the first pressure detection unit 240. As shown in FIG. 4, a recess 232 that opens in the -X direction is formed at the end of the force applying member 230 in the -X direction. The tip portion of the rod 220 in the +X direction is inserted into the opening of the recess 232. In the opening of the recess 232, the transmission unit 222 of the rod 220 is in contact with the bottom 233 of the recess 232 in the X direction. The rod 220 and the force applying member 230 are connected by a joint 234 that covers the side surface of the end of the force applying member 230 in the -X direction. The joint 234 has a shape that engages with the −X direction surface of the coupling portion 223 of the rod 220, and restricts the movement of the rod 220 in the −X direction relative to the force application member 230.

[0034] In this embodiment, a gap Gp is ​​formed between the side surface of the joint portion 223 of the rod 220 and the inner side surface of the recess 232. Therefore, the rod 220 contacts the force applying member 230 in the X direction, but does not contact the force applying member 230 in the Y direction or the Z direction. As a result, compared to, for example, a case where the gap Gp is ​​not provided between the rod 220 and the force applying member 230, the heat of the plasticized material in the flow path 66 is suppressed from being transmitted to the force applying member 230 via the rod 220, and further, the heat of the plasticized material is suppressed from being transmitted to the first pressure detection unit 240. Also, compared to, for example, a case where the rod 220 and the first pressure detection unit 240 are in direct contact with each other without the force applying member 230, the heat of the plasticized material is suppressed from being transmitted to the first pressure detection unit 240. Note that, in this embodiment, a gap is also formed between the side surface of the rod 220 and the joint portion 223.

[0035] The rod 220 transmits the pressure of the plasticized material in the flow path 66 to the first pressure detection unit 240. More specifically, the rod 220 receives a force in the +X direction due to the pressure of the plasticized material in the flow path 66 at the rod end surface 221, and transmits the force to the force application member 230 via the transmission unit 222. The force transmitted to the force application member 230 via the transmission unit 222 is transmitted to the first pressure detection unit 240 via the force application surface 231 of the force application member 230. Hereinafter, the force thus transmitted to the first pressure detection unit 240 via the transmission unit 222 may also be referred to as a detection force.

[0036] As shown in FIG. 4, the first pressure detection unit 240 includes a motor 250 having an output shaft 251 , and a torque member 260 connected to the output shaft 251 .

[0037] In this embodiment, the motor 250 is disposed such that the output shaft 251 faces the -Z direction along the Z direction perpendicular to the longitudinal direction of the rod 220. The motor 250 is configured by a servo motor. The first pressure detection unit 240 includes a controller 255 for servo-controlling the motor 250. In this embodiment, the driving of the motor 250 is controlled by the control unit 500 via the controller 255.

[0038] In this embodiment, the controller 255 performs position holding control, which performs feedback control so as to hold the rotational position of the output shaft 251. More specifically, when torque is applied to the output shaft 251 from the outside while the driving of the motor 250 is stopped, the controller 255 regulates the change in the rotational position of the output shaft 251 by generating a torque in the output shaft 251 in a direction opposite to that of the torque. In addition, when the rotational position of the output shaft 251 is changed by the torque applied from the outside, the controller 255 similarly generates a torque in the output shaft 251 in a direction opposite to that of the torque, thereby returning the rotational position of the output shaft 251 to its original state. Such position holding control is sometimes called a servo lock. Hereinafter, the torque for holding the rotational position of the output shaft 251 in the position holding control is sometimes called a position holding torque.

[0039] Fig. 5 is a view showing a VV cross section in Fig. 4. As shown in Figs. 4 and 5, the torque member 260 has a connection portion 261 and a force receiving portion 270.

[0040] The connection portion 261 in this embodiment is a substantially cylindrical member disposed along the Z direction. The connection portion 261 is formed with a connection hole 262 for connecting the output shaft 251 of the motor 250 and a fixing hole 263 for fixing the force receiving portion 270. As shown in FIG. 4, the connection hole 262 opens in the +Z direction at the end of the connection portion 261 in the +Z direction. The fixing hole 263 opens in the -Z direction at the end of the connection portion 261 in the -Z direction. In FIG. 5, the position of the connection hole 262 in the X direction and the Y direction is indicated by a two-dot chain line, and similarly, the position of the fixing hole 263 is indicated by a one-dot chain line. As shown in FIG. 5, the connection hole 262 is formed in the center of the connection portion 261 when viewed along the Z direction. The fixing hole 263 is formed at a position shifted from the center of the connection portion 261 when viewed along the Z direction. Therefore, the fixing hole 263 is positioned at a position shifted from the rotation axis RX of the output shaft 251 when viewed along the Z direction. The connection hole 262 may be formed in accordance with the shape of the output shaft 251, for example, in a shape corresponding to a D-cut shape or a shape corresponding to a key groove shape.

[0041] In this embodiment, the force receiving portion 270 is configured by a cam follower, and has a shaft 271 and an outer ring 272. A cam follower is sometimes called a track follower. The end of the shaft 271 in the +Z direction is inserted into the fixing hole 263 of the connecting portion 261 described above. The outer ring 272 is supported by a bearing 273 fixed to the side surface of the shaft 271 so as to be rotatable in place around the shaft 271. The outer ring 272 and the bearing 273 are disposed in the -Z direction of the connecting portion 261. The bearing 273 may be, for example, a ball bearing or a needle bearing.

[0042] As described above, the fixing hole 263 is formed at a position offset from the rotation axis RX. Therefore, as shown in Fig. 5, the force receiving portion 270 is disposed at a position offset from the rotation axis RX when viewed along the Z direction. More specifically, in this embodiment, the force receiving portion 270 is disposed at a position offset by a distance L in the -Y direction from the rotation axis RX when viewed along the Z direction.

[0043] The torque member 260 receives the above-mentioned detection force and applies a torque due to the detection force to the output shaft 251. In the present embodiment, the torque member 260 receives the detection force via the outer ring 272 of the force receiving portion 270, thereby generating a rotational force that rotates the connection portion 261 connected to the output shaft 251, and applies the torque generated by this rotational force to the output shaft 251. Hereinafter, the torque generated by the detection force and applied to the output shaft 251 may also be referred to as a detection torque.

[0044] The first pressure detection unit 240 in this embodiment detects the pressure of the plasticized material in the flow path 66 based on the current value or voltage value of the motor 250 generated by the detected torque applied to the output shaft 251. More specifically, the first pressure detection unit 240 detects a voltage value for generating a position holding torque corresponding to the detected torque while the above-mentioned controller 255 is performing position holding control, and detects the pressure of the plasticized material in the flow path 66 based on the detected voltage value. This allows the first pressure detection unit 240 to detect pressure while restricting the movement of the rod 220 and the force applying member 230 in the +X direction.

[0045] More specifically, if the pressure of the plasticized material in the flow passage 66 is taken as pressure P, in this embodiment, the pressure P is expressed by the following formula (1). P=(V·T) / (L·S·cosθ) (0<θ<180°)…(1) Voltage V represents the voltage value of motor 250 when detection torque is applied to output shaft 251. Torque T represents the rated torque of motor 250. Area S represents the area of ​​rod end face 221 of rod 220. Angle θ represents the angle between the transmission direction Df of the detection force and the rotation direction Dr of the torque member 260 that receives the detection force, the rotation direction Dr being the center of rotation around output shaft 251. In this embodiment, since both transmission direction Df and rotation direction Dr are in the +X direction, θ is 0°. Therefore, in this embodiment, the above formula (1) is equivalent to the following formula (2). P = (V T) / (L S)…(2)

[0046] Fig. 6 is a diagram showing an example of transmission of detection torque in another embodiment. Fig. 6 shows a state in which the force application member 230 and the force receiving portion 270 are in contact with each other in a state in which the torque member 260 has rotated counterclockwise compared to the case of Fig. 5 when viewed in the +Z direction. In the example shown in Fig. 6, since the transmission direction Df and the rotation direction Dr do not coincide with each other, when the torque member 260 receives the detection force, only the component of the received detection force in the rotation direction Dr contributes to the application of the detection torque to the output shaft 251.

[0047] As shown in the above formulas (1) and (2), when detecting the same pressure P, the smaller the distance L, the smaller the voltage V generated in the motor 250 when detecting the pressure P. Therefore, by making the distance L smaller, the load generated in the motor 250 when detecting the pressure P can be reduced. In other words, since it is preferable to set the voltage V generated in the motor 250 to be equal to or lower than the rated voltage of the motor 250 when detecting the pressure P, by making the distance L smaller, the range of detectable values ​​of the pressure P can be expanded. Furthermore, by making the distance L larger, the range of change in the voltage V relative to the change in the pressure P increases, and therefore the resolution of the detected pressure P can be improved.

[0048] The control unit 500 controls the operation of the above-mentioned suction and discharge unit 75 based on the pressure detection value by the first pressure detection unit 240. In this embodiment, the control unit 500 adjusts the operation timing, operation speed, retreat distance, or advance distance, etc. of the plunger of the suction and discharge unit 75 in the suction operation and the discharge operation based on the pressure detection value. For example, the control unit 500 can improve the responsiveness of the stop of the delivery of the plasticized material from the nozzle opening 62 by accelerating the timing of the plunger's retreat start or increasing the retreat speed as the pressure detection value becomes higher in the suction operation. Also, the control unit 500 can improve the responsiveness of the start of the delivery of the plasticized material from the nozzle opening 62 by accelerating the timing of the plunger's advance start or increasing the advance speed as the pressure detection value becomes lower in the delivery operation. Also, the control unit 500 may feedback control the suction and discharge unit 75 based on, for example, the pressure detection value. In this case, the control unit 500 may perform the suction operation when the pressure of the plasticized material in the flow path 66 becomes too high, and perform the discharge operation when the pressure becomes too low. Furthermore, the control unit 500 may adjust the flow rate of the plasticizing material in the flow passage 66, for example, by feedback controlling the delivery rate adjustment unit 70 based on the detected pressure value.

[0049] According to the three-dimensional modeling apparatus 100 in this embodiment described above, the rod 220 transmits the force due to the pressure of the plasticized material received at the rod end face 221 to the first pressure detection unit 240 via the transmission unit 222, and the first pressure detection unit 240 detects the pressure of the plasticized material in the flow path 66 via the rod 220. This allows the first pressure detection unit 240 to indirectly measure the pressure of the plasticized material in the flow path 66 via the rod 220. Therefore, even if a heat source is provided near the part where pressure is to be measured or the installation space near that part is limited, the possibility of detecting pressure at that part is increased.

[0050] Moreover, in this embodiment, the first pressure detection unit 240 has a motor 250 having an output shaft 251 and a torque member 260 that imparts a detection torque due to the received detection force to the output shaft 251, and the first pressure detection unit 240 detects the pressure of the plasticized material in the flow path 66 based on a current value or voltage value of the motor 250 generated by the detection torque. This makes it possible to detect the pressure of the plasticized material in the flow path 66 using the motor 250. Therefore, for example, the heat resistance of the first pressure detection unit 240 can be easily improved compared to a case in which the first pressure detection unit 240 is configured by a piezoelectric sensor that measures pressure by the piezoelectric effect of quartz or the like.

[0051] Furthermore, in this embodiment, the torque member 260 has a force receiving portion 270 that receives a detection force, at a position offset from the rotation axis RX of the output shaft 251 when viewed along the output shaft 251. Therefore, the torque member 260 can easily impart a detection torque to the output shaft 251 by receiving the detection force through the force receiving portion 270. Furthermore, by adjusting the distance L from the rotation axis RX of the force receiving portion 270, the width and resolution of the pressure values ​​detectable by the first pressure detection unit 240 can be easily adjusted.

[0052] Moreover, in this embodiment, force receiving portion 270 is configured by a cam follower. This allows the detection force to be transmitted to force receiving portion 270 more efficiently. This prevents wear and damage to force receiving portion 270 when the detection force is transmitted to force receiving portion 270. Note that in other embodiments, force receiving portion 270 may be configured by a roller follower, and even in this case, the detection force is transmitted to force receiving portion 270 more efficiently, and prevents wear and damage to force receiving portion 270 when the detection force is transmitted to force receiving portion 270.

[0053] In this embodiment, the screw 40 has a groove forming surface 42 in which the grooves 45 are formed, and the plasticizing section 30 includes a barrel 50 and a plasticizing heater 58. This allows the plasticizing section 30 to be made smaller, and therefore the entire material delivery device 150 can be made smaller.

[0054] Furthermore, in this embodiment, a nozzle heater 68 is provided, and the set temperature of the nozzle heater 68 is higher than the set temperature of the plasticizing heater 58. Therefore, the nozzle heater 68 can further increase the fluidity of the plasticizing material in the nozzle 61, and the plasticizing material can be efficiently sent out from the nozzle opening 62. Furthermore, even if the temperature of the flow path 66 near the nozzle 61 is increased by the nozzle heater 68, the first pressure detection unit 240 can easily detect the pressure of the plasticizing material in the flow path 66 near the nozzle 61 via the rod 220.

[0055] In addition, in this embodiment, the three-dimensional modeling apparatus 100 includes a delivery amount adjustment unit 70 arranged in the flow path 66 upstream of the connection between the flow path 66 and the cylinder 210. This allows the first pressure detection unit 240 to accurately detect the pressure of the plasticizing material downstream of the delivery amount adjustment unit 70 in the flow path 66. In particular, even if the flow rate of the plasticizing material downstream of the delivery amount adjustment unit 70 in the flow path 66 is adjusted to be small by the delivery amount adjustment unit 70, the pressure of the plasticizing material downstream of the delivery amount adjustment unit 70 can be accurately detected. Therefore, compared to a case in which the pressure detection unit 200 is connected upstream of the delivery amount adjustment unit 70 in the flow path 66, the mechanism and the like arranged downstream of the delivery amount adjustment unit 70 in the flow path 66 can be more accurately controlled based on the detected pressure. In addition, by controlling the delivery amount adjustment unit 70 based on the detected pressure, the delivery amount of the plasticizing material delivered from the nozzle opening 62 toward the stage 300 can be more accurately adjusted.

[0056] Furthermore, in this embodiment, the three-dimensional modeling apparatus 100 includes a suction and discharge unit 75 connected between the delivery rate adjustment unit 70 and the nozzle opening 62 in the flow path 66, and the control unit 500 controls the suction and discharge unit 75 based on a value detected by the first pressure detection unit 240. As a result, since both the pressure detection unit 200 and the suction and discharge unit 75 are connected between the delivery rate adjustment unit 70 and the nozzle opening 62 in the flow path 66, the suction and discharge unit 75 can be controlled with higher accuracy based on the pressure detected by the first pressure detection unit 240. Therefore, the responsiveness of starting and stopping the delivery of the plasticizing material from the nozzle opening 62 can be improved.

[0057] B. Second embodiment: 7 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus 100b in the second embodiment. The three-dimensional modeling apparatus 100b in this embodiment is different from the first embodiment in that it further includes a second pressure detection unit 298. Portions of the configuration of the three-dimensional modeling apparatus 100b that are not particularly described are similar to those in the first embodiment.

[0058] The second pressure detection unit 298 detects the pressure of the plasticized material upstream of the delivery amount adjustment unit 70 in the flow path 66. In this embodiment, the second pressure detection unit 298 is configured by a diaphragm type pressure sensor. The second pressure detection unit 298 is inserted into the through hole 57 penetrating the barrel 50 in the -X direction so as to block the through hole 57 from the -X direction. A tip 299 in the +X direction of the second pressure detection unit 298 faces the communication hole 56 in the through hole 57. The second pressure detection unit 298 detects the plasticized material in the communication hole 56 by receiving the pressure of the plasticized material in the through hole 57 at the tip 299. In another embodiment, the second pressure detection unit 298 may detect the pressure of the plasticized material not in the communication hole 56 but, for example, upstream of the delivery amount adjustment unit 70 in the supply flow path 67. In addition, the second pressure detection section 298 may be configured, for example, by a piezoelectric pressure sensor, or may be configured to measure pressure indirectly via a rod, similar to the first pressure detection section 240 of the pressure detection unit 200.

[0059] In this embodiment, the control unit 500 controls the rotation of the screw 40 based on the detection value of the pressure detected by the second pressure detection unit 298. For example, the control unit 500 can adjust the amount of plasticized material produced by the plasticizing unit 30 based on the pressure of the plasticized material upstream of the delivery amount adjustment unit 70 in the flow path 66 by feedback-controlling the drive motor 32 based on the detection value by the second pressure detection unit 298.

[0060] The above-described three-dimensional modeling apparatus 100b of the present embodiment also increases the possibility of measuring the pressure at a desired portion, even when a heat source is provided near the portion or when the installation space near the portion is limited. In particular, in the present embodiment, the flow path 66 includes a second pressure detection unit 298 that detects the pressure of the plasticizing material upstream of the delivery amount adjustment unit 70, and the control unit 500 controls the rotation of the screw 40 based on the detection value by the second pressure detection unit 298. According to this embodiment, the control unit 500 can adjust the amount of plasticizing material generated by the plasticizing unit 30 based on the pressure of the plasticizing material upstream of the delivery amount adjustment unit 70. This allows the flow rate of the plasticizing material upstream of the delivery amount adjustment unit 70 in the flow path 66 to be adjusted more accurately, making it easier to adjust the flow rate of the plasticizing material in the entire flow path 66. This increases the possibility of adjusting the delivery amount of the plasticizing material delivered from the nozzle opening 62 more accurately.

[0061] C. Third embodiment: 8 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus 100c in the third embodiment. In this embodiment, the three-dimensional modeling apparatus 100c does not include a suction and discharge unit 75, unlike the first embodiment. In the three-dimensional modeling apparatus 100c, a pressure detection unit 200c detects the pressure of the plasticized material in the flow path 66 and performs the same function as the suction and discharge unit 75 in the first embodiment. Parts of the configuration of the three-dimensional modeling apparatus 100c that are not particularly described are the same as those in the first embodiment.

[0062] As shown in FIG. 8, a force applying member 230c in this embodiment has a shaft portion 235 and a clamping portion 236, unlike the first embodiment.

[0063] FIG. 9 is a perspective view showing the pressure detection unit 200c in this embodiment. FIG. 10 is a view showing the XX cross section in FIG. 8. In FIG. 10, similar to FIG. 5 described in the first embodiment, the positions of the connection hole 262 in the X direction and the Y direction are indicated by two-dot chain lines, and the positions of the fixing hole 263 in the X direction and the Y direction are indicated by one-dot chain lines. In addition, in FIG. 10, the positions of the connection part 261 in the X direction and the Y direction are indicated by broken lines. As shown in FIG. 8 and FIG. 9, the shaft-shaped part 235 is a shaft-shaped member whose axial direction is the longitudinal direction, and is disposed so that the longitudinal direction is along the X direction. At the end of the shaft-shaped part 235 in the -X direction, a recess 232 is formed, similar to the force applying member 230 in the first embodiment.

[0064] The clamping portion 236 is penetrated in the X direction by the shaft-shaped portion 235 and fixed to the shaft-shaped portion 235. A groove portion 237 is formed along the Y direction at the end of the clamping portion 236 in the +Z direction. A first wall portion 238 is formed in the -X direction of the groove portion 237, and a second wall portion 239 is formed in the +X direction. An outer ring 272 of the force receiving portion 270 is disposed in the groove portion 237. That is, the outer ring 272 is sandwiched between the first wall portion 238 and the second wall portion 239 in the X direction.

[0065] The force application member 230c in this embodiment transmits the detection force to the first pressure detection unit 240 via the clamping portion 236. More specifically, the force is transmitted to the shaft-shaped portion 235 of the force application member 230c via the transmission portion 222 of the rod 220, whereby the clamping portion 236 is pushed in the +X direction together with the shaft-shaped portion 235. Then, the first wall portion 238 of the clamping portion 236 comes into contact with the outer ring 272 of the force receiving portion 270 and pushes the outer ring 272 in the +X direction, thereby transmitting the detection force to the force receiving portion 270. This allows the torque member 260 to apply the detection torque to the output shaft 251.

[0066] FIG. 11 is a diagram for explaining the operation of the first pressure detection unit 240 in the third embodiment. In this embodiment, the control unit 500 drives the motor 250 of the first pressure detection unit 240 to slide the rod 220 in the cylinder 210. For example, when viewed along the -Z direction, the control unit 500 rotates the motor 250 clockwise to rotate the torque member 260 clockwise, so that the force receiving portion 270 of the torque member 260 can push the second wall portion 239 of the clamping unit 236 in the +X direction as shown in FIG. 11. Then, the force applying member 230c moves in the +X direction together with the clamping unit 236, and the rod 220 retreats in the +X direction away from the flow path 66 with the movement of the force applying member 230c. As a result, the plasticized material in the flow path 66 is sucked into the cylinder 210. Similarly, the control unit 500 can rotate the motor 250 in the direction opposite to the direction in which the rod 220 is retracted, thereby causing the torque member 260 to push the first wall portion 238 in the -X direction. This causes the rod 220 to advance in the -X direction approaching the flow path 66, and the plasticized material in the cylinder 210 is pushed out toward the nozzle opening 62. In this manner, the control unit 500 can perform the suction operation and the discharge operation by operating the rod 220 within the cylinder 210, similar to the case of the suction and discharge unit 75 described in the first embodiment.

[0067] In this embodiment, the first pressure detection unit 240 also detects the pressure of the plasticized material in the flow path 66 based on the current value or voltage value of the motor 250 generated by the detection torque applied to the output shaft 251. The control unit 500 also executes the suction operation and discharge operation by the operation of the rod 220 described above based on the detection value by the first pressure detection unit 240. More specifically, the first pressure detection unit 240 performs position maintenance control of the motor 250 even when performing the suction operation and discharge operation described above, and generates a position maintenance torque for maintaining the rotational position of the output shaft 251 of the motor 250 at the control position in the suction operation or discharge operation when the detection force is transmitted via the rod 220 while the suction operation or discharge operation is being performed by the rod 220. Then, the first pressure detection unit 240 detects the pressure of the plasticized material in the flow path 66 based on the voltage value for generating this position maintenance torque. Also, the control unit 500 executes the suction and discharge operations by the rod 220 based on the detection value by the first pressure detection unit 240, in the same way as the suction and discharge operations by the suction and discharge unit 75 are executed based on the detection value by the first pressure detection unit 240 in the first embodiment. Note that, as shown in Fig. 10 and Fig. 11, the forward or backward movement of the rod 220 changes the angle θ between the transmission direction Df of the detection force and the rotation direction Dr of the torque member 260, but the first pressure detection unit 240 can detect the pressure P by the formula (1) described in the first embodiment.

[0068] Furthermore, in this embodiment, since force receiving portion 270 is configured by a cam follower, force receiving portion 270 can smoothly move in groove portion 237 along the Y direction while in contact with first wall portion 238 or second wall portion 239. Therefore, force receiving portion 270 can efficiently transmit the detection force from first wall portion 238, and can also efficiently transmit the force due to the rotation of motor 250 to first wall portion 238 or second wall portion 239.

[0069] The three-dimensional modeling apparatus 100c of the present embodiment described above also increases the possibility of measuring the pressure at a desired part, even if a heat source is provided near the part or the installation space near the part is limited. In particular, in the present embodiment, the control unit 500 executes an operation of retracting the rod 220 relative to the flow path 66 to suck the plasticized material in the flow path 66 into the cylinder 210, and an operation of advancing the rod 220 relative to the flow path 66 to push the sucked plasticized material toward the nozzle opening 62, based on the pressure detected by the first pressure detection unit 240. According to this embodiment, by operating the rod 220 within the cylinder 210 based on the detection value by the first pressure detection unit 240, it is possible to perform the suction and extrusion of the plasticized material based on the detection value without providing a member for suctioning and extruding the plasticized material separately from the cylinder 210 and the rod 220. Therefore, it is possible to realize a space-saving three-dimensional modeling apparatus 100c, and to improve the responsiveness of stopping and starting the delivery of the plasticized material from the nozzle opening 62.

[0070] D. Fourth embodiment: 12 is a diagram showing a schematic configuration of an injection molding apparatus 101 in the fourth embodiment. The injection molding apparatus 101 includes a material delivery device 150d, an injection control unit 600, a molding die 610, a clamping device 620, and a control unit 500d. The material delivery device 150d includes a plasticizing unit 30d, a nozzle 61d, and a pressure detection unit 200. The configurations of the material delivery device 150d, the pressure detection unit 200, and the control unit 500d in this embodiment are similar to those in the first embodiment unless otherwise specified.

[0071] In this embodiment, the communication hole 56 formed in the barrel 50d of the plasticizing section 30d forms the entire flow path 66. To the communication hole 56, an injection cylinder 601 of an injection control section 600 is connected.

[0072] The nozzle 61d in this embodiment delivers the plasticized material generated by the plasticizing section 30d from a nozzle opening 62d to the molding die 610. More specifically, the nozzle 61d injects the plasticized material into a cavity Cv of the molding die 610, which will be described later.

[0073] The molding die 610 has a movable die 611 and a fixed die 612 facing each other, with a cavity Cv between them. The cavity Cv is a space corresponding to the shape of the molded product. In this embodiment, the movable die 611 and the fixed die 612 are made of metal. In other embodiments, the movable die 611 and the fixed die 612 may be made of a ceramic material or a resin material.

[0074] The mold clamping device 620 includes a mold driving unit 621 and a ball screw unit 622. The mold driving unit 621 is composed of a motor, gears, etc., and is connected to the movable mold 611 via the ball screw unit 622. The driving of the mold driving unit 621 is controlled by the control unit 500. The ball screw unit 622 transmits the power generated by the driving of the mold driving unit 621 to the movable mold 611. Under the control of the control unit 500, the mold clamping device 620 opens and closes the casting mold 610 by moving the movable mold 611 using the mold driving unit 621 and the ball screw unit 622.

[0075] The injection control unit 600 includes an injection cylinder 601, an injection plunger 602, and a third drive unit 603. The injection cylinder 601 is connected to the communication hole 56. The injection plunger 602 is inserted into the injection cylinder 601. The injection cylinder 601 is driven by the third drive unit 603 and slides inside the injection cylinder 601. The third drive unit 603 is configured by, for example, a stepping motor, a rack-and-pinion mechanism, or the like, similar to the second drive unit 76 described in the first embodiment.

[0076] The injection control unit 600, under the control of the control unit 500, slides the injection plunger 602 in the injection cylinder 601 to perform a metering operation and an injection operation. The metering operation refers to an operation of guiding the plasticized material in the flow path 66 into the injection cylinder 601 by retracting the injection plunger 602 in a direction away from the flow path 66, as in the suction operation by the suction and discharge unit 75 described in the first embodiment, and metering the plasticized material in the injection cylinder 601. The injection operation refers to an operation of injecting the plasticized material in the injection cylinder 601 into the mold 610 through the nozzle 61d by advancing the injection plunger 602 in a direction approaching the flow path 66, as in the discharge operation by the suction and discharge unit 75 described in the first embodiment.

[0077] The cylinder 210 of the pressure detection unit 200 is connected to the flow path 66 in the same manner as in the first embodiment. More specifically, in this embodiment, the cylinder 210 is connected downstream of the injection cylinder 601 of the injection control unit 600 in the communication hole 56. In other embodiments, the cylinder 210 may be connected, for example, upstream of the injection cylinder 601 in the flow path 66. In this embodiment, the cylinder 210 and the rod 220 are arranged along the Z direction, and the cylinder 210 is connected to the flow path 66 from the +Z direction of the flow path 66. In addition, a pressure detection unit (not shown) configured in the same manner as the first pressure detection unit 240 shown in FIG. 1 is arranged in the +Z direction of the cylinder 210 and the rod 220. FIG. 12 shows the positions of the cylinder 210 and the rod 220 in the X direction and the Y direction.

[0078] In this embodiment, the control unit 500 can also control, for example, the drive of the injection control unit 600 based on the pressure detected by the first pressure detection unit of the pressure detection unit 200. For example, when performing a metering operation, the control unit 500 can adjust the retraction speed of the injection plunger 602 according to the pressure of the plasticized material in the communication hole 56, thereby preventing excessive plasticized material from being drawn into the injection cylinder 601 and preventing air from being mixed into the plasticized material in the injection cylinder 601. Furthermore, for example, when performing an injection operation, the control unit 500 can adjust the forward speed of the injection plunger 602 according to the pressure of the plasticized material in the communication hole 56, thereby preventing a shortage of the amount of plasticized material injected into the molding die 610 and the generation of residual stress caused by the plasticized material being injected into the molding die 610 with excessive pressure. Furthermore, the control unit 500 may adjust the number of rotations of the drive motor 32 of the plasticizing unit 30d, the speed and time at which the clamping unit 620 is driven, etc., according to the pressure detected by the first pressure detection unit, for example.

[0079] The injection molding apparatus 101 in this embodiment described above also increases the possibility of measuring pressure at a part where pressure is to be measured, even when a heat source is provided near the part or when installation space near the part is limited.

[0080] In other embodiments, the injection molding apparatus 101 may include another pressure detection unit configured similarly to the second pressure detection unit 298 described in the second embodiment, for example, upstream of the pressure detection unit 200 in the flow path 66. Also, for example, the injection molding apparatus 101 may not be provided with the injection control unit 600, and the pressure detection unit 200 may function as the injection control unit 600. In this case, the control unit 500d executes an operation of retracting the rod 220 to suck the plasticized material into the cylinder 210 and an operation of advancing the rod 220 to push the sucked plasticized material toward the nozzle opening 62, based on the detection value by the first pressure detection unit, in the same manner as in the case where the pressure detection unit 200c is caused to perform the same function as the suction and discharge unit 75 in the third embodiment. According to this embodiment, similarly to the third embodiment, by operating the rod 220 inside the cylinder 210 based on the detection value by the first pressure detection unit, it is possible to suck and push out the plasticized material based on the detection value without providing a member for sucking and pushing out the plasticized material separately from the cylinder 210 and the rod 220. Therefore, it is possible to realize space saving of the injection molding apparatus 101.

[0081] E. Other embodiments: (E-1) In the above embodiment, the transmission part 222 is an end face opposite to the rod end face 221 in the longitudinal direction of the rod 220. In contrast, the transmission part 222 does not have to be an end face opposite to the rod end face 221 in the longitudinal direction of the rod 220. For example, the transmission part 222 may be a side face of a portion between both end faces of the rod 220 in the longitudinal direction, or may be unevenness provided on a side face of a portion between both end faces of the rod 220 in the longitudinal direction.

[0082] (E-2) In the above embodiment, the pressure detection unit 200 has the force application member 230. In contrast, the pressure detection unit 200 does not have to have the force application member 230. For example, the transmission part 222 of the rod 220 may directly transmit the force due to the pressure of the plasticized material in the flow path 66 to the first pressure detection part 240.

[0083] (E-3) In the above embodiment, the first pressure detection unit 240 performs position maintenance control of the motor 250 when detecting the pressure of the plasticized material. In contrast, the first pressure detection unit 240 does not need to perform position maintenance control of the motor 250 when detecting the pressure of the plasticized material. In this case, the first pressure detection unit 240 may detect the pressure of the plasticized material in the flow path 66 based on, for example, the current value or voltage value of the regenerative power generated in the motor 250 when a detection torque is applied to the output shaft 251.

[0084] (E-4) In the above embodiment, the first pressure detection unit 240 has the motor 250. In contrast, the first pressure detection unit 240 does not have to have the motor 250. For example, the first pressure detection unit 240 may be configured with a piezoelectric pressure sensor, or may be configured with a diaphragm pressure sensor.

[0085] (E-5) In the above embodiment, the force receiving portion 270 is configured by a cam follower or a roller follower. In contrast, the force receiving portion 270 does not have to be configured by a cam follower or a roller follower.

[0086] (E-6) In the above embodiment, the plasticizing unit 30 of the material delivery device 150 plasticizes the material by a flat screw to generate the plasticized material. In contrast, the plasticizing unit 30 may generate the plasticized material by, for example, rotating an in-line screw. Also, in the three-dimensional modeling apparatus 100, the material delivery device 150 may be configured to plasticize a filament-like material and deliver the plasticized material from the nozzle opening 62.

[0087] (E-7) In the above embodiment, the set temperature of the nozzle heater 68 is higher than the set temperature of the plasticizing heater 58. In contrast, the set temperature of the nozzle heater 68 may be lower than or equal to the set temperature of the plasticizing heater 58. Also, for example, the nozzle heater 68 does not have to be provided.

[0088] (E-8) In the above embodiment, the delivery rate adjustment unit 70 is disposed in the flow path 66, upstream of the connection between the flow path 66 and the cylinder 210. In contrast, the delivery rate adjustment unit 70 may be disposed, for example, downstream of the connection between the flow path 66 and the cylinder 210. Also, the delivery rate adjustment unit 70 may not be provided.

[0089] (E-9) In the above embodiment, the suction and discharge unit 75 is connected in the flow path 66 between the delivery amount adjustment unit 70 and the nozzle opening 62. In contrast to this, the suction and discharge unit 75 may be disposed, for example, upstream of the delivery amount adjustment unit 70 in the flow path 66.

[0090] F. Other forms: The present disclosure is not limited to the above-mentioned embodiment, and can be realized in various forms without departing from the spirit of the present disclosure. For example, the present disclosure can be realized in the following forms. The technical features in the above-mentioned embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined in order 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 the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0091] (1) According to a first aspect of the present disclosure, there is provided a material delivery device. The material delivery device includes a plasticizing section having a screw and plasticizing a material by rotation of the screw to generate a plasticized material, a flow path through which the plasticized material flows, a nozzle communicating with the flow path and having a nozzle opening for delivering the plasticized material to the outside, a cylinder connected to the flow path, a rod inserted into the cylinder, and a first pressure detection section detecting the pressure of the plasticized material in the flow path via the rod. The rod has, in the longitudinal direction of the rod, a rod end face facing the flow path and a transmission section farther from the flow path than the rod end face, and transmits the force due to the pressure received at the rod end face to the first pressure detection section via the transmission section. According to this embodiment, the first pressure detection unit can indirectly measure the pressure of the plasticized material in the flow passage through the rod, which increases the possibility of detecting the pressure in the area where the pressure is to be measured, even if a heat source is provided near the area or the installation space near the area is limited.

[0092] (2) In the material delivery device of the above embodiment, the first pressure detection unit may have a motor having an output shaft and a torque member connected to the output shaft and receiving the force transmitted through the transmission unit, the torque member imparting a torque due to the received force to the output shaft, and the first pressure detection unit may detect the pressure based on a current value or a voltage value of the motor generated by the torque. According to this embodiment, the pressure of the plasticized material in the flow path can be detected using a motor. Therefore, for example, the heat resistance of the first pressure detection unit can be easily improved compared to a case where the first pressure detection unit is configured by a sensor that measures pressure by a piezoelectric effect.

[0093] (3) In the material delivery device of the above embodiment, the torque member may have a force receiving portion that receives the force transmitted via the transmission portion at a position offset from the rotation axis of the output shaft when viewed along the output shaft. According to this embodiment, the torque member can easily apply torque to the output shaft by receiving the force through the force receiving portion. In addition, by adjusting the distance from the rotation axis of the force receiving portion, the width and resolution of the detectable pressure value can be easily adjusted.

[0094] (4) In the material delivery device of the above embodiment, the force receiving portion may be configured by a cam follower or a roller follower. According to this embodiment, the detection force is transmitted to the force receiving portion more efficiently. Therefore, wear and damage to the force receiving portion when the detection force is transmitted to the force receiving portion is suppressed.

[0095] (5) In the material delivery device of the above embodiment, the screw may have a groove forming surface on which a groove is formed, the plasticizing unit may have an opposing surface facing the groove forming surface, the plasticizing unit may further include a barrel having a communication hole formed in the opposing surface forming at least a part of the flow path, and a plasticizing heater for heating the material supplied between the screw and the barrel. According to this embodiment, the plasticizing unit can be made smaller, and therefore the entire material delivery device can be made smaller.

[0096] (6) The material delivery device of the above embodiment may further include a nozzle heater for heating the nozzle, and the set temperature of the nozzle heater may be higher than the set temperature of the plasticizing heater. According to this embodiment, the nozzle heater can increase the fluidity of the plasticizing material in the nozzle, and the plasticizing material can be efficiently delivered to the outside from the nozzle opening. Even if the temperature of the flow path near the nozzle is increased by the nozzle heater, the pressure of the plasticizing material in the flow path near the nozzle can be easily detected by the first pressure detection unit via the rod 220.

[0097] (7) According to a second aspect of the present disclosure, a three-dimensional modeling apparatus is provided. The three-dimensional modeling apparatus includes the material delivery device of the above aspect, a stage for depositing the plasticized material delivered from the nozzle, a control unit for controlling the material delivery device, and a delivery amount adjustment unit arranged in the flow path upstream of a connection between the flow path and the cylinder and for adjusting the flow rate of the plasticized material delivered from the nozzle opening. According to this aspect, the first pressure detection unit can accurately detect the pressure of the plasticized material downstream of the delivery amount adjustment unit in the flow path. In particular, even if the delivery amount adjustment unit adjusts the flow rate of the plasticized material downstream of the delivery amount adjustment unit in the flow path to a smaller value, the pressure of the plasticized material downstream of the delivery amount adjustment unit can be accurately detected. Therefore, a mechanism or the like arranged downstream of the delivery amount adjustment unit in the flow path can be more accurately controlled based on the pressure detected by the first pressure detection unit.

[0098] (8) In the three-dimensional modeling apparatus of the above embodiment, the flow path may include a second pressure detection unit that detects the pressure of the plasticizing material upstream of the delivery amount adjustment unit, and the control unit may control the rotation of the screw based on the detection value by the second pressure detection unit. According to this embodiment, the control unit can adjust the amount of plasticizing material generated by the plasticizing unit based on the pressure of the plasticizing material upstream of the delivery amount adjustment unit. This makes it possible to more accurately adjust the flow rate of the plasticizing material upstream of the delivery amount adjustment unit in the flow path, making it easier to adjust the flow rate of the plasticizing material in the entire flow path. This increases the possibility of more accurately adjusting the amount of plasticizing material delivered from the nozzle opening.

[0099] (9) The three-dimensional modeling apparatus of the above embodiment may further include a suction and discharge unit connected in the flow path between the delivery rate adjustment unit and the nozzle opening, which sucks in the plasticized material in the flow path and pushes the sucked plasticized material toward the nozzle opening, and the control unit may control the suction and discharge unit based on a value detected by the first pressure detection unit. According to this embodiment, since both the cylinder and the suction and discharge unit are connected in the flow path between the delivery rate adjustment unit and the nozzle opening, the suction and discharge unit can be controlled with higher accuracy based on the pressure detected by the first pressure detection unit via a rod inserted in the cylinder. This can further improve the responsiveness of starting and stopping the delivery of the plasticized material from the nozzle opening.

[0100] (10) In the three-dimensional modeling apparatus of the above embodiment, the control unit may execute an operation of retracting the rod relative to the flow path to suck the plasticized material in the flow path into the cylinder, and an operation of advancing the rod relative to the flow path to push the sucked plasticized material toward the nozzle opening, based on the detection value by the first pressure detection unit. According to this embodiment, by operating the rod in the cylinder based on the detection value by the first pressure detection unit, it is possible to perform the suction and extrusion of the plasticized material based on the detection value without providing a member that sucks and extrudes the plasticized material separately from the cylinder and the rod. Therefore, it is possible to realize a space-saving three-dimensional modeling apparatus and to improve the responsiveness of stopping and starting the delivery of the plasticized material from the nozzle opening.

[0101] (11) According to a third aspect of the present disclosure, there is provided an injection molding apparatus comprising the material delivery device of the above aspect and a control unit that controls the material delivery device, wherein the nozzle delivers the plasticized material to a mold.

[0102] (12) In the injection molding apparatus of the above embodiment, the control unit may execute an operation of retracting the rod relative to the flow path to suck the plasticized material in the flow path into the cylinder, and an operation of advancing the rod relative to the flow path to push the sucked plasticized material toward the nozzle opening, based on the detection value by the first pressure detection unit. According to this embodiment, by operating the rod within the cylinder based on the detection value by the first pressure detection unit, it is possible to suck and push out the plasticized material without providing a member that sucks and pushes out the plasticized material separately from the cylinder and the rod. This makes it possible to reduce the space required for the injection molding apparatus. [Explanation of symbols]

[0103] 20...material supply section, 22...supply path, 30, 30d...plasticization section, 31...screw case, 32...drive motor, 40...screw, 41...upper surface, 42...groove forming surface, 43...side surface, 44...material inlet, 45...groove, 46...ridge portion, 47...center portion, 50, 50d...barrel, 52...screw facing surface, 54...guide groove, 56...communication hole, 57...through hole, 58...plasticization heater, 61, 61d...nozzle, 62, 62d... Nozzle opening, 63...tip surface, 65...nozzle flow passage, 66...flow passage, 67...supply flow passage, 68...nozzle heater, 70...delivery amount adjustment unit, 74...first drive unit, 75...suction and discharge unit, 76...second drive unit, 100, 100b, 100c...three-dimensional modeling device, 101...injection molding device, 150, 150d...material delivery device, 200, 200c...pressure detection unit, 210...cylinder, 220...rod, 221...rod end surface, 22 2...Transmission portion, 223...Connecting portion, 230, 230c...Force application member, 231...Force application surface, 232...Recessed portion, 233...Bottom portion, 234...Joint, 235...Axial portion, 236...Clasping portion, 237...Groove portion, 238...First wall portion, 239...Second wall portion, 240...First pressure detection portion, 250...Motor, 251...Output shaft, 255...Controller, 260...Torque member, 261...Connection portion, 262...Connection hole, 263...Fixing hole, 270...Force receiving portion 271...shaft, 272...outer ring, 273...bearing, 298...second pressure detection unit, 299...tip, 300...stage, 311...molding surface, 400...position change unit, 500, 500d...control unit, 600...injection control unit, 601...injection cylinder, 602...injection plunger, 603...third drive unit, 610...molding mold, 611...movable mold, 612...fixed mold, 620...mold clamping device, 621...mold drive unit, 622...ball screw unit

Claims

1. a plasticizing section having a screw and plasticizing the material by rotation of the screw to generate a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening communicating with the flow path and for delivering the plasticized material to the outside; A cylinder connected to the flow path; A rod inserted into the cylinder; a first pressure detection unit that detects the pressure of the plasticized material in the flow path via the rod; Equipped with the rod has, in a longitudinal direction of the rod, a rod end surface facing the flow path and a transmission portion farther from the flow path than the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission portion; the first pressure detection unit includes a motor having an output shaft, and a torque member connected to the output shaft and receiving the force transmitted via the transmission unit; The torque member applies a torque to the output shaft due to the received force, The material delivery device, wherein the first pressure detection unit detects the pressure based on a current value or a voltage value of the motor generated by the torque.

2. 2. The material delivery device of claim 1, A material delivery device, wherein the torque member has a force receiving portion that receives the force transmitted via the transmission portion at a position offset from the rotation axis of the output shaft when viewed along the output shaft.

3. 3. The material delivery device of claim 2, A material delivery device, wherein the force receiving portion is constituted by a cam follower or a roller follower.

4. A material delivery device according to any one of claims 1 to 3, A nozzle heater is provided to heat the nozzle, The screw has a groove forming surface on which a groove is formed, The plasticizing section includes: The groove forming surface has an opposing surface, and at least a part of the flow path is formed on the opposing surface. a barrel having a communication hole formed therein; A plasticizing heater that heats the material supplied between the screw and the barrel, A material delivery device, wherein the nozzle heater has a set temperature higher than the set temperature of the plasticizing heater.

5. A plasticizing section having a screw and plasticizing a material by rotation of the screw to generate a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening communicating with the flow path and for delivering the plasticized material to the outside; A cylinder connected to the flow path; A rod inserted into the cylinder; a first pressure detection unit that detects the pressure of the plasticized material in the flow path via the rod; a suction and discharge section connected to the flow path between the screw and the nozzle opening, for sucking the plasticized material in the flow path and pushing the sucked plasticized material toward the nozzle opening; Equipped with the rod has, in a longitudinal direction of the rod, a rod end surface facing the flow path and a transmission portion farther from the flow path than the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission portion; A material delivery device, wherein the cylinder is connected to the flow path between the suction and discharge portion and the nozzle opening, or to the flow path between the screw and the suction and discharge portion.

6. A material delivery device; A control unit for controlling the material delivery device; Equipped with The material delivery device includes: a plasticizing section having a screw and plasticizing the material by rotation of the screw to generate a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening communicating with the flow path and for delivering the plasticized material to the outside; A cylinder connected to the flow path; A rod inserted into the cylinder; a first pressure detection unit that detects the pressure of the plasticized material in the flow path via the rod; a delivery amount adjusting section disposed in the flow path upstream of a connection between the flow path and the cylinder, the delivery amount adjusting section adjusting a flow rate of the plasticizing material delivered from the nozzle opening; a stage for depositing the plasticized material delivered from the nozzle; having The rod has, in the longitudinal direction of the rod, a rod end surface facing the flow path and a transmission portion that is farther from the flow path than the rod end surface, and transmits the force due to the pressure received at the rod end surface to the first pressure detection portion via the transmission portion.

7. The three-dimensional modeling apparatus according to claim 6, the material delivery device has a second pressure detection unit that detects a pressure of the plasticizing material upstream of the delivery amount adjustment unit in the flow path, The control unit controls rotation of the screw based on a detection value by the second pressure detection unit.

8. A three-dimensional printing apparatus according to claim 6 or 7, the material delivery device has a suction and discharge section connected to the flow path between the screw and the nozzle opening, which suctions the plasticized material in the flow path and pushes the sucked plasticized material toward the nozzle opening; The suction and discharge unit is connected between the delivery amount adjustment unit and the nozzle opening in the flow path, The control unit controls the suction and discharge unit based on a detection value by the first pressure detection unit.

9. A three-dimensional printing apparatus according to claim 6 or 7, The control unit of the three-dimensional printing device performs the operation of retracting the rod relative to the flow path to suck the plasticized material in the flow path into the cylinder based on the detection value by the first pressure detection unit, and the operation of advancing the rod relative to the flow path to push the sucked plasticized material toward the nozzle opening.

10. A material delivery device; A control unit for controlling the material delivery device; Equipped with The material delivery device includes: a plasticizing section having a screw and plasticizing the material by rotation of the screw to generate a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening communicating with the flow path and for delivering the plasticized material to the outside; A cylinder connected to the flow path; A rod inserted into the cylinder; a first pressure detection unit that detects the pressure of the plasticized material in the flow path via the rod; having the rod has, in a longitudinal direction of the rod, a rod end surface facing the flow path and a transmission portion farther from the flow path than the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission portion; The nozzle delivers the plasticized material to a mold.

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