Injection molding apparatus and material dispensing apparatus

Abstract

This invention provides a technology that can reduce the possibility of material stagnation or material leakage outside the flow path in an injection molding machine. [Solution] The injection molding apparatus comprises an injection unit that injects a plasticized material, which is made by plasticizing the material of the molded product, into a molding mold; a clamping unit to which the molding mold is attached and that clamps the molding mold; and a control unit that controls the injection unit and the clamping unit.The injection unit comprises a plasticizing section that plasticizes the material to produce a plasticized material, a nozzle that supplies the plasticized material to the molding mold, a flow path that connects the plasticizing section and the nozzle, and a supply adjustment mechanism provided in the flow path that adjusts the amount of plasticized material supplied from the nozzle to the molding mold.The supply adjustment mechanism comprises a cylinder connected to the flow path, a plunger placed in the cylinder, and a drive section that drives the plunger.The flow path and the cylinder consist of a first member that is integrated.

Description

[Technical Field]

[0001] The present disclosure relates to an injection molding apparatus and a material dispensing apparatus. [Background technology]

[0002] Patent Document 1 discloses an injection molding device having an injection cylinder and an injection plunger. Molten resin is supplied to the injection cylinder from a flow path that communicates with a plasticizing section. As the injection plunger slides within the injection cylinder, the molten resin is injected from the injection cylinder into a mold through the flow path and nozzle through which the molten resin flows. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-157601 Summary of the Invention [Problem to be solved by the invention]

[0004] When the flow path through which the molten resin flows and the injection cylinder are formed from separate materials, the material may accumulate at the boundary between the flow path and the injection cylinder, or may enter tiny gaps at the boundary, causing leakage of the material outside the flow path. This issue is not limited to injection molding machines, but is also common to material discharge devices that have a flow path and a cylinder. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided an injection molding apparatus for injection molding a molded product using a mold including a fixed mold and a movable mold movable relative to the fixed mold. The injection molding apparatus includes an injection unit that injects a plasticized material obtained by plasticizing a material of the molded product into the mold, a clamping unit to which the mold is attached and that clamps the mold, and a control unit that controls the injection unit and the clamping unit. The injection unit includes a plasticizing section that plasticizes the material to produce the plasticized material, a nozzle that supplies the plasticized material to the mold, a flow path that connects the plasticizing section and the nozzle, and a supply adjustment mechanism that is provided in the flow path and adjusts the amount of plasticized material supplied from the nozzle to the mold. The supply adjustment mechanism includes a cylinder connected to the flow path, a plunger disposed in the cylinder, and a drive unit that drives the plunger. The flow path and the cylinder are formed as a first member.

[0006] According to a second aspect of the present disclosure, there is provided a material discharging device including: a plasticizing unit that plasticizes a material to produce a plasticized material; a nozzle that supplies the plasticized material to the outside; a flow path that connects the plasticizing unit and the nozzle; and a supply adjustment mechanism that is provided in the flow path and adjusts the amount of the plasticized material supplied from the nozzle to the outside, the supply adjustment mechanism having a cylinder connected to the flow path, a plunger disposed in the cylinder, and a drive unit that drives the plunger, and the flow path and the cylinder are integrated into a first member. [Brief explanation of the drawings]

[0007] [Figure 1] This is a front view showing the schematic configuration of the injection molding apparatus in the first embodiment. [Figure 2] This is a cross-sectional view showing the schematic configuration of an injection molding apparatus. [Figure 3] This is a perspective view showing the general configuration of the screw. [Figure 4] FIG. 2 is a schematic plan view of the barrel. [Figure 5] FIG. 3 is a cross-sectional view of a first member. [Figure 6] This is a perspective view of a portion of the first component, cut away. [Figure 7] This diagram shows the plunger positioned inside the cylinder. [Figure 8] This figure shows the test results of the material substituteability evaluation test. [Figure 9] This is an explanatory diagram showing the configuration of the injection unit in the second embodiment. [Figure 10] This is a flowchart of the protrusion amount adjustment process in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] A. First embodiment: Figure 1 is a front view showing the schematic configuration of the injection molding apparatus 10 in the first embodiment. Figure 1 shows arrows indicating the mutually orthogonal X, Y, and Z directions. The X and Y directions are parallel to the horizontal plane, and the Z direction is opposite to the direction of gravity. The X, Y, and Z directions shown in Figure 2 and subsequent figures correspond to the X, Y, and Z directions shown in Figure 1. In the following description, when specifying directions, the positive direction indicated by the arrow will be denoted as "+" and the negative direction opposite to the direction indicated by the arrow will be denoted as "-", and positive and negative signs will be used in conjunction with the direction notation.

[0009] The injection molding apparatus 10 comprises an injection unit 40 and a clamping unit 50. The injection unit 40 is also called a material ejection device. The injection unit 40 and the clamping unit 50 are each fixed to a base 20. The base 20 is equipped with a control unit 500. The injection molding apparatus 10 forms a molded product by injecting plasticizing material from the injection unit 40 into a mold 12 mounted on the clamping unit 50. In this embodiment, a metal mold 12 is mounted on the clamping unit 50. The mold 12 mounted on the clamping unit 50 is not limited to metal, but may be made of resin or ceramic. A metal mold 12 is called a mold.

[0010] A hopper 30 into which material for the molded article is poured is connected to the injection unit 40. As the material for the molded article, for example, a thermoplastic resin formed into pellets is used.

[0011] The injection unit 40 plasticizes at least a portion of the material supplied from the hopper 30 to produce a plasticized material, and then injects the plasticized material into the molding die 12 attached to the mold clamping unit 50. In this specification, "plasticization" is a concept that includes melting and refers to changing a material from a solid to a fluid state. Specifically, for materials that undergo glass transition, plasticization refers to raising the temperature of the material above the glass transition point. For materials that do not undergo glass transition, plasticization refers to raising the temperature of the material above the melting point.

[0012] The control unit 500 is configured by a computer equipped with one or more processors, a main memory device, and an input / output interface for inputting and outputting signals from and to the outside. The processor loads and executes a program on the main memory device, causing the control unit 500 to control the injection unit 40 and the mold clamping unit 50 and manufacture molded products.

[0013] FIG. 2 is a cross-sectional view showing a schematic configuration of the injection molding apparatus 10. As described above, the injection molding apparatus 10 includes the injection unit 40 and the mold clamping unit 50. The injection unit 40 includes a plasticizing section 110, a nozzle 114, a flow path 116, and a supply adjustment mechanism 120. The plasticizing section 110 plasticizes a material to produce a plasticized material. The nozzle 114 supplies the plasticized material to the outside of the injection unit 40. The flow path 116 connects the plasticizing section 110 and the nozzle 114. The supply adjustment mechanism 120 is provided in the flow path 116 and adjusts the amount of plasticized material supplied from the nozzle 114 to the outside.

[0014] The plasticizing unit 110 includes a screw 111 and a barrel 112. The screw 111 is housed in a screw case 101 that contains the screw 111. The screw 111 is also called a rotor, scroll, or flat screw. The screw 111 is rotationally driven within the screw case 101 around the rotation axis RX by a screw drive unit 115, which consists of a drive motor 118 and a reduction gear 300. In this embodiment, the X direction is the direction along the rotation axis RX. A heater 113 for heating the material is embedded in the barrel 112. The rotation of the screw 111 by the screw drive unit 115 and the heating by the heater 113 are controlled by a control unit 500.

[0015] Figure 3 is a perspective view showing the schematic configuration of the screw 111. The screw 111 has a substantially cylindrical shape in which the length in the direction along its central axis is smaller than the length in the direction perpendicular to the central axis. On the groove-forming surface 201 of the screw 111 facing the barrel 112, a spiral groove 202 is formed, centered on the central part 205. The groove 202 communicates with a material inlet 203 formed on the side of the screw 111. The material supplied from the hopper 30 is supplied to the groove 202 through the material inlet 203. The groove 202 is formed by being separated by a protruding ridge 204. Figure 3 shows an example in which three grooves 202 are formed, but the number of grooves 202 may be one or two or more. Note that the groove 202 is not limited to a spiral shape, but may also be helical or involute curved, or may extend in an arc from the central part toward the outer circumference.

[0016] FIG. 4 is a schematic plan view of the barrel 112. The barrel 112 has an opposing surface 212 that faces the groove-forming surface 201 of the screw 111. A communication hole 213 is formed in the center of the opposing surface 212, through which the plasticized material flows out. The opposing surface 212 is formed with a plurality of guide grooves 211 that are connected to the communication hole 213 and extend spirally from the communication hole 213 toward the outer periphery. The material supplied to the groove 202 of the screw 111 is plasticized between the screw 111 and the barrel 112 by the rotation of the screw 111 and the heating of the heater 113. Then, the material flows along the groove 202 and the guide groove 211 due to the rotation of the screw 111 and is guided to the center portion 205 of the screw 111. The material that has flowed into the center portion 205 is guided to the flow path 116 from the communication hole 213 provided in the center of the barrel 112. Note that the guide groove 211 does not necessarily have to be connected to the communication hole 213. Also, the barrel 112 does not necessarily have to be provided with the guide groove 211.

[0017] 2, supply adjustment mechanism 120 includes cylinder 121, plunger 122, and plunger drive unit 123 that drives plunger 122. Under the control of control unit 500, supply adjustment mechanism 120 adjusts the amount of plasticizable material supplied from nozzle 114 to the outside of injection unit 40, i.e., to molding die 12.

[0018] The cylinder 121 is connected to the flow path 116. A plunger 122 is disposed inside the cylinder 121. The plunger 122 slides inside the cylinder 121 and pressure-feeds the plasticized material in the cylinder 121 to the nozzle 114. The plunger 122 is driven by a plunger drive unit 123 formed by a motor.

[0019] The molding die 12 comprises a movable die 13 and a fixed die 14. The movable die 13 and the fixed die 14 are disposed facing each other, and have a cavity 117 therebetween, which is a space corresponding to the shape of the molded product. Plasticized material pressure-fed by a supply adjustment mechanism 120 is injected from a nozzle 114 into the cavity 117.

[0020] The clamping unit 50 is equipped with a mold drive unit 131 and has the function of opening and closing the movable mold 13 and the fixed mold 14. Under the control of the control unit 500, the clamping unit 50 rotates a ball screw 132 by driving the mold drive unit 131, which is composed of a motor, and moves the movable mold 13, which is coupled to the ball screw 132, relative to the fixed mold 14 to open and close the mold 12. In other words, the fixed mold 14 is stationary in the injection molding apparatus 10, and the opening and closing of the mold 12 is performed by the relative movement of the movable mold 13 relative to the stationary fixed mold 14.

[0021] Figure 5 is a cross-sectional view of the first member 220. Figure 6 is a perspective view of a part of the first member 220. The flow path 116 and cylinder 121 described above are formed in the first member 220. In other words, the flow path 116 and cylinder 121 are made up of the first member 220 in which the flow path 116 and cylinder 121 are integrated. The first member 220 can be formed, for example, by cutting the parts corresponding to the flow path 116 and cylinder 121 from a metal block that will be the material for the first member 220. Alternatively, the first member 220 can be formed by metal joining the metal material in which the cylinder 121 is formed and the metal material in which the flow path 116 is formed by diffusion bonding or the like. The barrel 112 is in contact with the first member 220. The communication hole 213 of the barrel 112 communicates with the flow path 116 formed in the first member 220. The barrel 112 is made up of a second member 221 which is different from the first member 220. The first member 220 and the second member 221 are not integrated. The first member 220 and the second member 221 may be formed from the same type of material or from different types of material.

[0022] A valve element 124 is disposed within the flow path 116 of the first member 220. The valve element 124 is disposed within the flow path 116, upstream of the connection point between the flow path 116 and the cylinder 121. In this embodiment, the valve element 124 has a spherical shape. The position of the valve element 124 changes when the plasticized material flows from the plasticizing section 110 into the flow path 116 and when the plasticized material is injected from the nozzle 114. When the plasticized material flows from the plasticizing section 110 into the flow path 116, the valve element 124 receives pressure from the plasticizing section 110 and moves to the downstream side of the flow path 116. When the plasticized material is injected, the valve element 124 receives pressure from the plunger 122 and moves to the upstream side of the flow path 116. When the plasticizing material is injected, the valve element 124 moves upstream of the flow path 116 to block the opening of the flow path 116, thereby preventing the plasticizing material from flowing back from the flow path 116 to the plasticizing section 110. The valve element 124 is also called a check valve.

[0023] A restricting portion 222 is provided on the wall surface of the flow channel 116 to restrict the amount of fluctuation in the position of the valve element 124 when the plasticizing material flows from the plasticizing portion 110 into the flow channel 116. In this embodiment, the restricting portion 222 has a hemispherical shape that protrudes from the wall surface of the flow channel 116. The base end portion of the restricting portion 222 is formed in a cylindrical shape and is embedded in the wall surface of the flow channel 116. The maximum cross-sectional area of ​​the portion of the restricting portion 222 that protrudes into the flow channel 116 is smaller than the maximum cross-sectional area of ​​the valve element 124. In other words, in this embodiment, the diameter of the hemispherical portion of the restricting portion 222 is smaller than the diameter of the spherical valve element 124.

[0024] FIG. 7 is a diagram showing the plunger 122 disposed within the cylinder 121. In this embodiment, the tip 126 of the plunger 122 has a first flat surface 224. As shown in FIGS. 6 and 7, the wall surface of the flow path 116 formed in the first member 220 facing the tip 126 of the plunger 122 has a second flat surface 225 aligned with the first flat surface 224. In this embodiment, the first flat surface 224 and the second flat surface 225 are parallel to each other. In this embodiment, upon completion of injection of the plasticized material into the mold 12, the distance between the first flat surface 224 and the second flat surface 225 is approximately 0.5 mm. At this time, the tip 126 of the plunger 122 is positioned within the flow path 116, and the side surface 127 of the plunger 122 contacts the opening edge 128 of the cylinder 121.

[0025] In the injection unit 40, the control unit 500 controls the plunger driver 123 to perform a suction operation and a delivery operation. The suction operation is an operation in which the plasticized material is sucked into the cylinder 121 from the flow path 116 by moving the plunger 122 backward. The delivery operation is an operation in which the plasticized material sucked into the cylinder 121 is delivered to the nozzle 114 by moving the plunger 122 forward. "Forward" refers to the direction in which the plunger 122 approaches the flow path 116. "Backward" refers to the direction in which the plunger 122 moves away from the flow path 116. The control unit 500 controls the injection amount, injection speed, and injection pressure of the plasticized material from the nozzle 114 by adjusting the movement amount and movement speed of the plunger 122 during the suction operation and the delivery operation. The suction operation is also called a metering operation.

[0026] After the injection unit 40 performs a delivery operation and injects the plasticized material from the nozzle 114 into the cavity 117, the clamping unit 50 drives the ball screw 132 to move the movable mold 13 in the +X direction, which is the mold opening direction, relative to the fixed mold 14, thereby opening the mold. When the mold is opened, an ejector pin (not shown) incorporated in the movable mold 13 protrudes relatively into the cavity 117, and the molded product is released from the cavity 117.

[0027] Figure 8 shows the results of a material changeability evaluation test. In this material changeability evaluation test, the state of resin adhesion to the plunger during material changeover in the injection molding machine was observed using the plunger with a flat tip in the first embodiment and a plunger with a conical tip. Figure 8 shows the plunger with a flat tip as an example and the plunger with a conical tip as a comparative example.

[0028] The material changeability evaluation test included an injection process, a purging process, and a cleaning process. In the injection process, five shots of injection molding were performed using ABS (acrylonitrile butadiene styrene) resin. In the purging process, five shots of a commercially available molding machine cleaner were injected after the injection process to purge the material in the flow path 116. In the cleaning process, the plunger tip was positioned within the flow path, the distance between the plunger tip and the flow path was set to 3.5 mm, and the molding machine cleaner was allowed to flow for 100 seconds. Figure 8 shows images of the plunger tip after the injection process, the purging process, and the cleaning process for the example and comparative example.

[0029] As shown in Figure 8, after the injection process, a large amount of molten resin adhered to the tip of the plunger of the Comparative Example, whereas the amount of resin adhered to the plunger of the Example was not so large. After the purging process, the same amount of cleaning agent adhered to both the Comparative Example and the Example. After the cleaning process, a large amount of cleaning agent adhered to the tip of the plunger of the Comparative Example, whereas the amount of cleaning agent adhered to the tip of the plunger of the Example was small. Therefore, this material changeability evaluation test confirmed that a plunger with a flat tip can be used for material and color change more easily than a plunger with a conical tip.

[0030] According to the injection molding apparatus 10 of the first embodiment described above, the flow path 116 through which the plasticized material flows and the cylinder 121 in which the plunger 122 slides are integrated into the first member 220. Therefore, there is no gap between the flow path 116 and the cylinder 121. This prevents the plasticized material from leaking from the gap between the flow path 116 and the cylinder 121 or from accumulating in the gap between the flow path 116 and the cylinder 121. As a result, it is possible to reduce the possibility of the injection molding apparatus 10 being soiled by material leakage or damage to components in contact with the flow path 116 due to increased surface pressure caused by material leakage.

[0031] Furthermore, in this embodiment, the valve element 124 that suppresses backflow of the plasticized material from the flow path 116 to the plasticizing section 110 is provided not in the communication hole 213 of the barrel 112 or in the boundary between the barrel 112 and the first member 220, but in the flow path 116 formed in the first member 220. This makes it possible to suppress leakage of material between the barrel 112 and the first member 220 when the plasticized material is injected. As a result, it is possible to reduce the possibility of the injection molding apparatus 10 being soiled by material leakage or damage to the boundary between the first member 220 and the barrel 112 due to increased surface pressure caused by material leakage.

[0032] Furthermore, in this embodiment, a restricting portion 222 that restricts the amount of fluctuation in the position of the valve element 124 is provided on the wall surface of the flow path 116. Therefore, the movement of the valve element can be restricted with a simple structure. In particular, in this embodiment, the cross-sectional area of ​​the restricting portion 222 is smaller than the cross-sectional area of ​​the valve element 124. That is, in this embodiment, the restricting portion 222 is formed small. This reduces the pressure applied to the restricting portion 222 during injection, thereby reducing the possibility of damage to the restricting portion 222 and preventing material from leaking from the damaged area.

[0033] Furthermore, in this embodiment, when the injection of the plasticizing material is completed, the tip 126 of the plunger 122 is located within the flow path 116, and the side surface 127 of the plunger 122 is in contact with the opening edge 128 of the cylinder 121. Therefore, the possibility of material in the flow path 116 entering the cylinder 121 and causing material stagnation during injection of the plasticizing material is suppressed. This prevents wear and damage to the plunger 122 and cylinder 121 caused by the solidification of the stagnant material. In addition, when switching materials used for molding, it is possible to suppress the stagnant material from mixing with the material used after the switch.

[0034] Furthermore, in this embodiment, the tip 126 of the plunger 122 has a first plane 224, and the wall surface of the flow channel 116 facing the tip 126 of the plunger 122 has a second plane 225 along the first plane 224. Therefore, the gap between the tip 126 of the plunger 122 and the flow channel 116 can be reduced when injecting the plasticizing material. As a result, the amount of material remaining in the flow channel 116 after injection can be reduced, making it easier to change materials or colors.

[0035] B. Second embodiment: Figure 9 is an explanatory diagram showing the configuration of the injection unit 40b in the second embodiment. The injection unit 40b in the second embodiment includes a limiting unit drive unit 226 that drives the limiting unit 222. The limiting unit drive unit 226 is controlled by the control unit 500 and is configured to change the amount of protrusion of the limiting unit 222 from the wall surface of the flow path 116. The other configurations in the second embodiment are the same as in the first embodiment.

[0036] 10 is a flowchart of the protrusion amount adjustment process executed in the second embodiment. This protrusion amount adjustment process is a process for adjusting the protrusion length of the restricting portion 222 into the flow path 116. The protrusion amount adjustment process is executed before the molding cycle of the injection molding is started.

[0037] In step S10, the control unit 500 receives a designation of the type of material. The type of material is received, for example, by the user operating an operation unit connected to the control unit 500.

[0038] In step S20, the control unit 500 changes the amount of protrusion of the restriction portion 222 from the wall surface of the flow path 116 depending on the type of material specified. In this embodiment, the control unit 500 reduces the amount of protrusion of the restriction portion 222 for a material with a higher viscosity. In other words, the control unit 500 increases the amount of protrusion of the restriction portion 222 for a material with a lower viscosity. Because the tip of the restriction portion 222 is formed in a hemispherical shape, a smaller amount of protrusion of the restriction portion 222 increases the amount of downstream movement of the valve element 124, and a larger amount of protrusion of the restriction portion 222 decreases the amount of downstream movement of the valve element 124. The greater the amount of downstream movement of the valve element 124, the larger the gap between the valve element 124 and the flow path 116. Therefore, by reducing the amount of protrusion of the restriction portion 222 for a material with a higher viscosity, the material can more easily flow through the flow path 116.

[0039] According to the second embodiment described above, the control unit 500 can shorten the time it takes for a highly viscous material to flow into the cylinder 121 by changing the amount of protrusion of the restrictor 222 from the wall surface of the flow path 116 depending on the viscosity of the material. As a result, the manufacturing efficiency of molded products using highly viscous materials can be improved.

[0040] C. Other Embodiments: (C1) In the above embodiment, the valve element 124 is disposed in the flow path 116 formed in the first member 220. However, the valve element 124 may be disposed in the communication hole 213 of the barrel 112 instead of in the flow path 116.

[0041] (C2) In the above embodiment, the cross-sectional area of ​​the restricting portion 222 is smaller than the cross-sectional area of ​​the valve body 124. However, it is also possible to configure the cross-sectional area of ​​the restricting portion 222 to be larger than the cross-sectional area of ​​the valve body 124.

[0042] (C3) In the above embodiment, when injection of the plasticized material is completed, the tip 126 of the plunger 122 is located within the flow path 116, and the side surface 127 of the plunger 122 contacts the opening edge 128 of the cylinder 121. In contrast, when injection of the plasticized material is completed, the tip 126 of the plunger 122 may remain within the cylinder 121.

[0043] (C4) In the above embodiment, the tip 126 of the plunger 122 is flat, and the wall surface of the flow path 116 facing the tip 126 of the plunger 122 is also flat. In contrast, the tip 126 of the plunger 122 does not have to be flat, and the wall surface of the flow path 116 facing the tip 126 does not have to be flat either.

[0044] (C5) The injection unit 40 in the first embodiment may be mounted on a three-dimensional modeling apparatus as a material discharging device. The three-dimensional modeling apparatus includes a stage facing the nozzle 114 of the material discharging device. The three-dimensional modeling apparatus forms a three-dimensional object by layering the plasticized material discharged from the nozzle 114 on the stage while changing the relative position between the nozzle 114 and the stage. The plunger 122 included in the material discharging device is used, for example, to temporarily decrease or increase the flow rate of the plasticized material discharged toward the stage. Note that the material discharging device included in the three-dimensional modeling apparatus does not necessarily have to include the valve body 124.

[0045] D. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features of the embodiments corresponding to the technical features in each aspect described below can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0046] (1) According to a first aspect of the present disclosure, there is provided an injection molding apparatus for injection molding a molded product using a mold including a fixed mold and a movable mold movable relative to the fixed mold. The injection molding apparatus includes an injection unit that injects a plasticized material obtained by plasticizing a material of the molded product into the mold, a clamping unit to which the mold is attached and that clamps the mold, and a control unit that controls the injection unit and the clamping unit. The injection unit includes a plasticizing section that plasticizes the material to produce the plasticized material, a nozzle that supplies the plasticized material to the mold, a flow path that connects the plasticizing section and the nozzle, and a supply adjustment mechanism that is provided in the flow path and adjusts the amount of plasticized material supplied from the nozzle to the mold. The supply adjustment mechanism includes a cylinder connected to the flow path, a plunger disposed in the cylinder, and a drive unit that drives the plunger. The flow path and the cylinder are formed as a first member. According to this embodiment, the flow path through which the plasticized material flows and the cylinder are integrated into a first member. Therefore, there is no gap between the flow path and the cylinder. This prevents the plasticized material from leaking from the gap between the flow path and the cylinder or from accumulating in the gap between the flow path and the cylinder.

[0047] (2) In the above embodiment, the plasticizing section may include a screw and a barrel made of a second member different from the first member and having a through-hole communicating with the flow path. The injection unit may include a valve body that prevents backflow of the plasticizing material from the flow path to the plasticizing section during injection of the plasticizing material, the valve body being disposed within the flow path. According to this embodiment, the valve body is disposed not in the through-hole of the barrel but in the flow path formed in the first member. Therefore, leakage of the plasticizing material from the joint between the plasticizing section and the first member during injection of the plasticizing material can be prevented. This reduces the possibility of contamination of the injection molding apparatus 10 due to material leakage or damage to the joint between the first member and the barrel due to increased surface pressure caused by material leakage.

[0048] (3) In the above embodiment, the valve body has a position that changes when the plasticizing material flows from the plasticizing section into the flow path and when the plasticizing material is injected, and the wall surface of the flow path is provided with a limiting section that limits the amount of change in the position of the valve body when the plasticizing material flows from the plasticizing section into the flow path. With such an embodiment, the movement of the valve body can be restricted with a simple structure.

[0049] (4) In the above configuration, the cross-sectional area of ​​the limiting portion may be smaller than the cross-sectional area of ​​the valve body. With this configuration, since the limiting portion is formed to be small, the pressure applied to the limiting portion during injection can be reduced. As a result, the possibility of damage to the limiting portion can be reduced.

[0050] (5) In the above configuration, the control unit may change the amount of the limiting portion protruding from the wall surface of the flow path according to the viscosity of the material. With this configuration, the amount of variation of the valve body can be appropriately adjusted according to the viscosity of the material, etc.

[0051] (6) In the above configuration, when the injection of the plasticizing material is completed, the tip of the plunger may be located within the flow path, and the side surface of the plunger may be in contact with the opening edge of the cylinder. With this configuration, the possibility of material in the flow path entering the cylinder during injection and causing material stagnation is suppressed. This prevents the stagnant material from solidifying and causing wear or damage to the plunger or cylinder due to the solidified material. In addition, when switching materials used for molding, it is possible to suppress the stagnant material from mixing with the material used after the switch.

[0052] (7) In the above configuration, the tip may have a first plane, and the wall surface of the flow channel facing the tip may have a second plane along the first plane. With this configuration, the gap between the tip of the plunger and the flow channel during injection can be reduced. As a result, the amount of material remaining in the flow channel after injection can be reduced, making it easier to change materials or colors.

[0053] (8) According to a second aspect of the present disclosure, there is provided a material discharging device including: a plasticizing unit that plasticizes a material to produce a plasticized material; a nozzle that supplies the plasticized material to the outside; a flow path that connects the plasticizing unit and the nozzle; and a supply adjustment mechanism that is provided in the flow path and adjusts the amount of the plasticized material supplied from the nozzle to the outside, the supply adjustment mechanism having a cylinder connected to the flow path, a plunger disposed in the cylinder, and a drive unit that drives the plunger, and the flow path and the cylinder are integrated into a first member. [Explanation of symbols]

[0054] 10...injection molding apparatus, 12...molding mold, 13...movable mold, 14...fixed mold, 20...base, 30...hopper, 40...injection unit, 40b...injection unit, 50...mold clamping unit, 101...screw case, 110...plasticizing section, 111...screw, 112...barrel, 113...heater, 114...nozzle, 115...screw drive section, 116...flow path, 117...cavity, 118...drive motor, 120...supply adjustment mechanism, 121...cylinder, 122...plan Jar, 123... plunger drive part, 124... valve body, 126... tip, 127... side surface, 128... opening edge part, 131... forming mold drive part, 132... ball screw, 201... groove forming surface, 202... groove, 203... material inlet, 204... ridge part, 205... center part, 211... guide groove, 212... opposing surface, 213... communicating hole, 220... first member, 221... second member, 222... limiting part, 224... first flat surface, 225... second flat surface, 226... limiting part drive part, 300... reducer, 500... control part

Claims

1. An injection molding apparatus for injection molding a molded product using a mold including a fixed mold and a movable mold that is movable relative to the fixed mold, an injection unit that plasticizes the material of the molded article and injects the plasticized material into the mold; A clamping unit to which the mold is attached and to clamp the mold, a control unit that controls the injection unit and the mold clamping unit; Equipped with The injection unit is, a plasticizing section that plasticizes the material to produce the plasticized material; A nozzle for supplying the plasticizing material to the mold, A flow path connecting the plasticizing portion and the nozzle, a supply adjustment mechanism provided in the flow path for adjusting the amount of the plasticizing material supplied from the nozzle to the molding die; and The aforementioned supply adjustment mechanism is A cylinder connected to the aforementioned flow path, a plunger disposed within the cylinder; A drive unit for driving the plunger, and The flow path and the cylinder are made of a first integrated member. Injection molding equipment.

2. An injection molding apparatus according to claim 1, The plasticizing portion is, Screw and, It comprises a barrel made of a second member different from the first member, and having a communication hole that communicates with the flow path, The injection unit has a valve that suppresses the backflow of the plasticizing material from the flow path to the plasticizing section when the plasticizing material is injected. The valve body is an injection molding apparatus provided within the flow path.

3. An injection molding apparatus according to claim 1, The valve body has a position that changes when the plasticizing material flows from the plasticizing section into the flow path and when the plasticizing material is injected. An injection molding apparatus, wherein a wall surface of the flow path is provided with a limiting portion that limits the amount of fluctuation in the position of the valve body when the plasticizing material flows from the plasticizing portion into the flow path.

4. An injection molding apparatus according to claim 3, An injection molding apparatus, wherein the cross-sectional area of ​​the restriction portion is smaller than the cross-sectional area of ​​the valve body.

5. An injection molding apparatus according to claim 3, The control unit changes the amount of the limiting portion protruding from the wall surface of the flow path according to the viscosity of the material, in an injection molding apparatus.

6. 2. The injection molding apparatus according to claim 1, An injection molding apparatus, wherein when injection of the plasticized material is completed, the tip of the plunger is positioned within the flow path and the side surface of the plunger contacts the opening edge of the cylinder.

7. An injection molding apparatus according to claim 6, The tip has a first plane, an injection molding apparatus, wherein a wall surface of the flow path facing the tip has a second plane aligned with the first plane.

8. a plasticizing section for plasticizing the material to produce a plasticized material; a nozzle for supplying the plasticized material to the outside; A flow path connecting the plasticizing portion and the nozzle, a supply adjusting mechanism provided in the flow path for adjusting the amount of the plasticizing material supplied from the nozzle to the outside; Equipped with The aforementioned supply adjustment mechanism is A cylinder connected to the aforementioned flow path, a plunger disposed within the cylinder; A drive unit for driving the plunger, and The flow path and the cylinder are made of a first integrated member. Material discharge device.

Images