Injection molding machine

Abstract

To provide an injection molding machine capable of easily performing maintenance such as cleaning of branch flow paths.SOLUTION: There is provided an injection molding machine, comprising: a material supply unit that supplies a molding material containing a plasticized thermoplastic resin; a manifold having a main flow path that communicates with the material supply unit and a plurality of branch flow paths that branch off from the main flow path; an injection unit that is connected to each of the branch flow paths and has a plurality of nozzles that inject the molding material into a mold unit; a positioning unit that positions the injection unit and the mold unit; and a control unit that controls an operation of the material supply unit and the injection unit, wherein the manifold has a first member and a second member that are separate from each other and can be assembled and separated, and when the first member and the second member are assembled, a branch flow path is formed at a boundary between the first member and the second member.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an injection molding machine. [Background technology]

[0002] 2. Description of the Related Art Conventionally, injection molding apparatuses have been known that manufacture resin molded products by injecting a resin material, such as a plasticized thermoplastic resin, from a nozzle into a cavity formed in a mold.

[0003] For example, Patent Document 1 discloses an injection molding device having a supply unit that supplies heated resin, a manifold connected to the supply unit and having an internal flow path, and a nozzle connected to the manifold and communicating with the internal flow path. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-305625 Summary of the Invention [Problem to be solved by the invention]

[0005] In the injection molding apparatus described in Patent Document 1, the manifold has multiple internal flow paths with a relatively small inner diameter. Because the internal flow paths of the manifold have a complex structure and the main portion of the manifold is made of a single material, maintenance, such as cleaning the internal flow paths, is difficult. If maintenance is not performed properly, some of the internal flow paths may become clogged, hindering the flow of molten resin and causing other problems, which may ultimately result in a decrease in molding quality during injection molding. [Means for solving the problem]

[0006] The injection molding machine of the present invention includes: a material supply unit that supplies a molding material containing a plasticized thermoplastic resin; a manifold having a main flow path communicating with the material supply unit and a plurality of branch flow paths branching from the main flow path, and an injection unit having a plurality of nozzles connected to each of the branch flow paths and configured to inject the modeling material into a mold portion; a positioning unit that positions the injection unit and the mold unit; a control unit that controls the operation of the material supply unit and the injection unit, the manifold has a first member and a second member that are separate from each other and can be assembled and separated; In an assembled state of the first member and the second member, the branch flow path is formed at the boundary between the first member and the second member. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of an injection molding machine according to an embodiment of the present invention. [Figure 2] 2 is a top view of an injection unit provided in the injection molding machine shown in FIG. 1. FIG. [Figure 3] 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 4] 4 is a cross-sectional view showing a state in which the first member and the second member shown in FIG. 3 are separated. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An injection molding machine according to the present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. First Embodiment Fig. 1 is a cross-sectional view showing a schematic configuration of an injection molding machine according to an embodiment of the present invention. Fig. 2 is a top view of an injection unit provided in the injection molding machine shown in Fig. 1, seen from above. Fig. 3 is a cross-sectional view taken along line AA in Fig. 2. Fig. 4 is a cross-sectional view showing a state in which the first member and the second member shown in Fig. 3 are separated (hereinafter sometimes simply referred to as a "separated state").

[0009] The up-down direction in FIG. 1 coincides with the vertical direction, and the upper side in FIGS. 1, 3 and 4 will also be referred to as "upper" and the lower side as "lower."

[0010] 1 and 2 also show x-, y-, and z-axes that are orthogonal to each other, with the direction indicated by the arrow being the "+" side and the opposite side being the "-" side. The z-axis coincides with the vertical direction, and the x- and y-axes are parallel to the horizontal direction.

[0011] In this specification, "vertical" refers not only to the case where the object is perpendicular to the vertical, but also to the case where the object is slightly tilted from the vertical, for example, within ±10°. In this specification, "parallel" refers not only to the case where two objects are parallel to each other, but also to the case where the object is slightly tilted from the vertical, for example, within ±10°.

[0012] The injection molding machine 100 shown in Fig. 1 includes a material supply unit 1, an injection unit 2, a mold unit 3, a positioning unit 4, and a control unit 5. The material supply unit 1, the injection unit 2, and the mold unit 3 are arranged in this order from top to bottom in Fig. 1.

[0013] The material supply unit 1 supplies a modeling material M containing a plasticized resin to the injection unit 2. The plasticized modeling material M includes, for example, a thermoplastic resin that has been melted or softened by heating. The material supply unit 1 has a plasticizing unit (not shown) that heats and plasticizes, for example, pellet-shaped or powder-shaped solid resin.

[0014] Examples of thermoplastic resins include polyolefins such as AS resin, ABS resin, polyethylene, polypropylene, and ethylene-vinyl acetate copolymer (EVA), modified polyolefins, acrylic resins such as polymethyl methacrylate, polyesters such as polyvinyl chloride, polystyrene, polyethylene terephthalate, and polybutylene terephthalate, polyamides (Nylon: registered trademark) such as nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6-12, and nylon 6-66, liquid crystal polymers such as polyphenylene ether, polyacetal, polyether, polyphenylene oxide, polyether ether ketone, polycarbonate, polyphenylene sulfide, thermoplastic polyimide, polyetherimide, and aromatic polyester, and various thermoplastic elastomers such as styrene-based, polyolefin-based, polyvinyl chloride-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based. One or more types selected from these may be used in combination. The modeling material M may also contain powders of various metal materials, various alloys, and the like.

[0015] There are no particular limitations on the melting temperature or softening temperature of the modeling material M. The temperature of the plasticized modeling material M, particularly the temperature of the molten modeling material M, depends on the composition of the modeling material M, but is, for example, about 50°C or higher and 350°C or lower.

[0016] Plasticization mainly refers to plasticization caused by heating, and is a concept that includes glass transition, softening, and melting, and refers to changing from a solid to a fluid state. Specifically, for materials that undergo glass transition, plasticization means raising the temperature of the material above the glass transition point. For materials that do not undergo glass transition, plasticization means raising the temperature of the material above the softening point or melting point.

[0017] The material supply unit 1 has a supply nozzle 11 extending in the z-axis direction. The supply nozzle 11 has a supply flow path 12 extending in the z-axis direction inside. The modeling material M is supplied to the injection unit 2 through the supply flow path 12.

[0018] In addition, the supply flow path 12 may be provided with a means for promoting the transfer and supply of the modeling material M, such as a screw, a feeder, a pressure unit, or the like (not shown).

[0019] The lower end of supply nozzle 11 forms a resin discharge portion, which is connected to injection portion 2. Injection portion 2 has a manifold 21 and a plurality of nozzles 22 arranged below it. The lower end of supply nozzle 11 is connected to the upper center of manifold 21.

[0020] As shown in FIG. 2, the manifold 21 is a block-shaped or plate-shaped member that is connected to the supply nozzles 11 of the material supply unit 1 and supplies the modeling material M supplied from the material supply unit 1 to each of the multiple nozzles 22.

[0021] The manifold 21 is made up of a first member 6 and a second member 7 that can be assembled and separated. The first member 6 and the second member 7 are separate bodies and are each made up of a plate-shaped member. However, this configuration is not limited to this, and at least one of the first member 6 and the second member 7 may be made up of another form, for example, a block-shaped member.

[0022] The manifold 21 has a main flow path 211 and a plurality of branch flow paths 212 (four in this embodiment) branching from the main flow path 211. Hereinafter, the four branch flow paths 212 will also be referred to as branch flow path 212A, branch flow path 212B, branch flow path 212C, and branch flow path 212D.

[0023] A main flow path 211 is formed in the first member 6. The main flow path 211 is a sprue extending in the z-axis direction, and the upper end of the main flow path 211 is connected to the lower end of the supply flow path 12 of the supply nozzle 11, thereby connecting the supply flow path 12 and the main flow path 211. The main flow path 211 is located in the center of the manifold 21 in a plan view, i.e., when viewed from the z-axis direction.

[0024] The upper end of the main channel 211 is open to the +z-axis side, and the lower end is located near the center in the thickness direction of the manifold 21, i.e., in the z-axis direction. The cross section of the main channel 211 cut on the xy plane has a circular shape. However, the cross section is not limited to this configuration and may have a shape other than a circle, such as an ellipse, a rectangle, or another polygon.

[0025] When the first member 6 and the second member 7 are joined at their lower surface 61 and upper surface 71 to be assembled, branch flow paths 212A, 212B, 212C, and 212D are formed at the boundary 8 between the first member 6 and the second member 7. The branch flow paths 212A, 212B, 212C, and 212D are runners that branch out radially from the lower end of the main flow path 211 at equal angular intervals (90° intervals in this embodiment). The number of branch flow paths 212 is not limited to four, and the branch flow paths 212 do not have to be arranged radially. Furthermore, even when multiple branch flow paths 212 are arranged radially, they do not have to be arranged at equal angular intervals.

[0026] Branch flow path 212A, branch flow path 212B, branch flow path 212C and branch flow path 212D each have a first portion 213 extending horizontally, i.e., on a plane parallel to the xy plane, and a second portion 214 extending vertically, i.e., in the z-axis direction.

[0027] The first portion 213 is a portion that branches radially from the main channel 211. The second portion 214 extends vertically downward from the end of the first portion 213 that is farther from the main channel 211.

[0028] The lengths of the first portions 213 in the branch flow channels 212A, 212B, 212C, and 212D are equal. The lengths of the second portions 214 in the branch flow channels 212A, 212B, 212C, and 212D are equal.

[0029] However, this configuration is not limited to this, and some of the branch flow paths 212A, 212B, 212C, and 212D may have a first portion 213 of a different length than the others, and a second portion 214 of a different length than the others.

[0030] The branch flow paths 212A, 212B, 212C, and 212D have a circular cross-sectional shape, but are not limited to this configuration and may have a shape other than a circle, such as an ellipse, a rectangle, or another polygon.

[0031] Branch flow channels 212A, 212B, 212C, and 212D each have a constant inner diameter along the longitudinal direction of the channel. Branch flow channels 212A, 212B, 212C, and 212D each have the same inner diameter.

[0032] However, the present invention is not limited to this configuration, and some of the branch flow paths 212A, 212B, 212C, and 212D may have inner diameters that are different from the others. Furthermore, each of the branch flow paths 212A, 212B, 212C, and 212D may have a portion with a different inner diameter.

[0033] As described above, branch flow paths 212A, 212B, 212C, and 212D are arranged radially around main flow path 211 when viewed from the direction in which main flow path 211 extends. This allows branch flow paths 212A, 212B, 212C, and 212D to be arranged so as to spread evenly in manifold 21. This allows nozzles 22 to be installed in a well-balanced manner.

[0034] 2 and 3, the manifold 21 has a pair of mounting holes 215 in which the first heaters 216 are installed. Each of the pair of mounting holes 215 extends in the x-axis direction. The pair of mounting holes 215 are provided parallel to and spaced apart from each other in the y-axis direction. The first heaters 216 have an elongated shape corresponding to the mounting holes 215. Each branch flow path 212 is located between the pair of mounting holes 215. That is, branch flow paths 212A, 212B, 212C, and 212D are located between the pair of first heaters 216.

[0035] By operating each first heater 216, it is possible to heat almost the entire manifold 21, and the modeling material M flowing through the main flow path 211, the branch flow paths 212A, 212B, the branch flow paths 212C, and the branch flow paths 212D can be heated to a desired temperature. Therefore, the viscosity, i.e., the fluidity, of the modeling material M can be maintained within a desired range, and the modeling material M can be ejected from the nozzle 22 satisfactorily and stably.

[0036] By locating the branch flow paths 212A, 212B, 212C, and 212D between the pair of first heaters 216, particularly in the middle of the pair of first heaters 216, it is possible to uniformly heat the modeling material M in the branch flow paths 212A, 212B, 212C, and 212D. As a result, the modeling material M can be ejected from each nozzle 22 (ejection nozzle 22A, 22B, 22C, and 22D) more favorably, uniformly, and stably.

[0037] As described above, the manifold 21 has a pair of first heaters 216 spaced apart from each other, and the branch flow paths 212A, 212B, 212C, and 212D are located between the pair of first heaters 216. This allows the modeling material M in the branch flow paths 212A, 212B, 212C, and 212D to be heated evenly. This allows the modeling material M to be ejected from each nozzle 22 more efficiently and stably.

[0038] Each first heater 216 is electrically connected to the control unit 5, and the control unit 5 controls the conditions for supplying electricity to the first heaters 216, thereby setting the heating temperature of the first heaters 216.

[0039] The control unit 5 has at least one processor, a memory unit, etc. The processor reads and executes a program stored in the memory unit, thereby controlling the material supply unit 1, the injection unit 2, etc. as described herein.

[0040] The manifold 21 also has a pressure detection unit 217. The pressure detection unit 217 has a pressure sensor 217A, a pressure sensor 217B, a pressure sensor 217C, and a pressure sensor 217D. The pressure sensor 217A detects the pressure of the modeling material M flowing in the branch flow path 212A. The pressure sensor 217B detects the pressure of the modeling material M flowing in the branch flow path 212B. The pressure sensor 217C detects the pressure of the modeling material M flowing in the branch flow path 212C. The pressure sensor 217D detects the pressure of the modeling material M flowing in the branch flow path 212D.

[0041] The pressure sensors 217A, 217B, 217C, and 217D are electrically connected to the control unit 5, and information related to the pressures detected by the pressure sensors 217A, 217B, 217C, and 217D is transmitted as an electric signal to the control unit 5. This information related to the pressures can be used to monitor each part of the injection molding machine 100, for example, to detect malfunctions, and for various controls. For example, if the detection value of the pressure sensor 217A among the pressure sensors 217A, 217B, 217C, and 217D falls outside a reference value, the notification can be used to determine whether the viscosity (fluidity) of the modeling material M flowing through the branch flow path 212A and the associated flow rate are appropriate or inappropriate. Furthermore, based on this determination, the flow rate of the modeling material M flowing through the branch flow path 212A can be changed and adjusted by operating the flow rate adjustment unit 218 (described later), or the temperature of the injection nozzle 22A can be changed and adjusted by adjusting the output of the second heater 222 installed in the injection nozzle 22A. These controls can be performed automatically by the control unit 5.

[0042] As described above, the injection molding machine 100 includes a pressure detection unit 217 that detects the pressure of the molding material M flowing through the branch flow paths 212A, 212B, 212C, and 212D. Furthermore, when the number of nozzles 22 used changes, the control unit 5 preferably controls the operation of the injection unit 2 to perform trial injection until the pressure value measured by the pressure detection unit 217 becomes constant. This allows the molding material M to be injected into the mold unit 3 at a constant pressure value. Therefore, a molded product that is more appropriate and meets the intended purpose and meets the required quality can be obtained. The trial injection refers to the nozzle 22 injecting the molding material M into a portion other than the mold unit 3. For example, an operator may prepare a disposal unit for disposing of the molding material M and position the disposal unit directly below the nozzle 22 to perform the trial injection. When the pressure value measured by the pressure detection unit 217 becomes constant and the trial injection is complete, the disposal unit is removed, and the molding material M is injected into the mold unit 3.

[0043] The manifold 21 also has a flow rate adjusting unit 218 that adjusts the flow rate of the modeling material M flowing through the branch flow channels 212A, 212B, 212C, and 212D.

[0044] The flow rate adjusting portion 218 has a plurality of insertion holes 219, four in this embodiment, and a rod-shaped member 220 inserted into each of the insertion holes 219.

[0045] The insertion holes 219 are each configured as a hole that extends along the z-axis direction and opens onto the +z-axis side surface of the manifold 21. The lower ends of the insertion holes 219 communicate with the connection portions 230 of the first portion 213 and the second portion 214 in the branch flow paths 212A, 212B, 212C, and 212D.

[0046] The rod-shaped member 220 is configured to be insertable into and removable from the insertion hole 219. When inserted downward to the deepest point, the lower end of the rod-shaped member 220 blocks the connection portion 230 between the first portion 213 and the second portion 214 in the branch flow channels 212A, 212B, 212C, and 212D, thereby blocking all or part of the flow channels. Furthermore, by adjusting the insertion depth of the rod-shaped member 220, it is possible to increase or decrease the effective cross-sectional area of ​​the connection portion 230 between the first portion 213 and the second portion 214. Therefore, it is possible to adjust the flow rate of the modeling material M flowing through each of the branch flow channels 212A, 212B, 212C, and 212D.

[0047] The vertical movement of each rod-shaped member 220 relative to the insertion hole 219 can be either all moved in unison or independently. In the latter case, the flow rate of the modeling material M can be adjusted for each of the branch flow paths 212A, 212B, 212C, and 212D. For example, if the detection value of the pressure sensor 217A among the pressure sensors 217A, 217B, 217C, and 217D deviates from the reference value, the rod-shaped member 220 corresponding to the branch flow path 212A can be raised or lowered to change or adjust the flow rate of the modeling material M flowing through the branch flow path 212A.

[0048] The vertical movement of each rod-shaped member 220 can be achieved by driving a driving source such as a motor (not shown). This driving source is electrically connected to the control unit 5, and the control unit 5 controls the driving of the driving source.

[0049] As described above, the flow rate adjusting unit 218 adjusts the flow rate of the modeling material M flowing through the branch flow paths 212A, 212B, 212C, and 212D. Preferably, the control unit 5 controls the operation of the flow rate adjusting unit 218 so that unused nozzles 22 among the multiple nozzles 22 are closed. This eliminates the need for operations such as attaching and detaching the nozzles 22, and allows the modeling material M to be supplied only to the nozzles 22 that are to be used according to the shape of the mold part 3. This allows for the production of molded products that are more appropriate and suited to the purpose, and that meet the required quality.

[0050] Although the flow rate adjusting section 218 has been described as having four insertion holes 219 and a rod-shaped member 220 inserted into each insertion hole 219, the present invention is not limited to this, and may be configured, for example, with valves that adjust the opening degree of branch flow paths 212A, branch flow paths 212B, branch flow paths 212C, and branch flow paths 212D.

[0051] 2 and 3, a plurality of nozzles 22, four nozzles 22 in this embodiment, are installed on the lower end surface of manifold 21, i.e., the surface on the -z axis side. Each nozzle 22 is connected to each second portion 214 of corresponding branch flow channel 212A, branch flow channel 212B, branch flow channel 212C, and branch flow channel 212D. Each nozzle 22 has an internal flow channel 221, and internal flow channel 221 communicates with branch flow channel 212A, branch flow channel 212B, branch flow channel 212C, and branch flow channel 212D, respectively.

[0052] Hereinafter, the nozzle 22 connected to the second portion 214 of the branch flow path 212A will be referred to as the injection nozzle 22A, the nozzle 22 connected to the second portion 214 of the branch flow path 212B will be referred to as the injection nozzle 22B, the nozzle 22 connected to the second portion 214 of the branch flow path 212C will be referred to as the injection nozzle 22C, and the nozzle 22 connected to the second portion 214 of the branch flow path 212D will be referred to as the injection nozzle 22D.

[0053] Each of the injection nozzles 22A, 22B, 22C, and 22D has a second heater 222 that heats the nozzle. By operating the second heater 222, the modeling material M passing through the internal flow path 221 can be heated. Therefore, the viscosity (fluidity) of the modeling material M can be maintained within a desired range, and the modeling material M can be injected from the nozzle 22 in a good and stable manner.

[0054] The second heater 222 is embedded in a position different from the internal flow path 221 and parallel to the internal flow path 221. That is, the second heater 222 is a rod-shaped heater. This allows the modeling material M passing through the internal flow path 221 to be heated more uniformly and efficiently.

[0055] Each second heater 222 is electrically connected to the control unit 5, and the control unit 5 controls the conditions for supplying electricity to the second heaters 222, thereby making it possible to set the heating temperature of the second heaters 222.

[0056] The second heater 222 is not limited to a rod-shaped heater as in this embodiment, but may be, for example, a coil-shaped heater disposed on the outer periphery of the nozzle 22.

[0057] As described above, the nozzle 22 has the second heater 222 that heats the nozzle 22. This prevents a decrease in the temperature of the modeling material M ejected from the nozzle 22, and maintains the viscosity (fluidity) of the modeling material M within a desired range. As a result, the modeling material M can be ejected from the nozzle 22 in a good and stable manner.

[0058] In this embodiment, a second heater 222 is installed in each of all nozzles 22, i.e., injection nozzle 22A, injection nozzle 22B, injection nozzle 22C, and injection nozzle 22D, but this is not limited to this, and second heaters 222 may be installed in only some of the nozzles 22 out of all the nozzles 22.

[0059] The nozzle 22 also has a temperature sensor 223 that detects the temperature of the modeling material M inside the nozzle 22. The temperature sensors 223 are each electrically connected to the control unit 5, and information regarding the temperature detected by each temperature sensor 223 is transmitted to the control unit 5 as an electrical signal. This allows the control unit 5 to control the operation of the corresponding second heater 222 or the first heater 216 based on the detected value of each temperature sensor 223. This makes it possible to adjust or maintain the temperature of the modeling material M injected from the nozzle 22 within a desired range. As a result, the quality of the molded product obtained by the injection molding machine 100 can be improved.

[0060] In this embodiment, the temperature sensor 223 can continuously, intermittently, or stepwise detect the temperature of the nozzle 22 or the modeling material M inside the nozzle 22. However, the present invention is not limited to this, and the temperature sensor 223 may be configured simply as a thermocouple. For example, a predetermined reference temperature may be set, and the temperature sensor 223 may detect whether or not the reference temperature is exceeded.

[0061] As described above, the nozzle 22 has the temperature sensor 223 that detects the temperature of the modeling material M inside the nozzle 22. This makes it possible to control the operation of the corresponding second heater 222 or first heater 216, for example, based on the detected value of each temperature sensor 223. This makes it possible to adjust or maintain the temperature of the modeling material M ejected from the nozzle 22 within a desired range.

[0062] Furthermore, it is preferable that the control unit 5 controls the operation of the second heater 222 based on the detection value of the temperature sensor 223, and adjusts the flow rate of the modeling material M ejected from the multiple nozzles 22. This allows the modeling material M to be ejected from the nozzles 22 with high accuracy, taking into account changes in the flow rate of the modeling material M due to temperature changes.

[0063] In this embodiment, a temperature sensor 223 is installed in each of all nozzles 22, i.e., injection nozzle 22A, injection nozzle 22B, injection nozzle 22C, and injection nozzle 22D, but this is not limited to this, and temperature sensors 223 may be installed in only some of the nozzles 22 out of all the nozzles 22.

[0064] The mold unit 3 shown in Fig. 1 has a molding die (not shown), in particular a metal mold, in which a cavity corresponding to the shape of the desired molded product is formed. The molding material M injected from each nozzle 22 of the injection unit 2 is supplied to and fills the cavity. The molding material M is then cooled and solidified, producing a molded product.

[0065] The molding die may have four cavities formed for each of injection nozzle 22A, injection nozzle 22B, injection nozzle 22C, and injection nozzle 22D, or may have a common cavity formed for any two or more of injection nozzle 22A, injection nozzle 22B, injection nozzle 22C, and injection nozzle 22D.

[0066] The positioning unit 4 positions the injection unit 2 and the mold unit 3 and secures the injection unit 2 and the mold unit 3 together. The positioning unit 4 is block-shaped and has through holes into which each nozzle 22 is inserted. Although not shown, the positioning unit 4 also has a securing means that can selectively secure or release the injection unit 2 and the mold unit 3. This increases the positional accuracy of each nozzle 22 relative to the mold unit 3 and enables the nozzles 22 to stably inject the molding material M.

[0067] As described above, the manifold 21 is made up of the first member 6 and the second member 7, which can be assembled and separated. The first member 6 and the second member 7 are separate bodies and are each made up of a plate-shaped member. However, this configuration is not limited thereto, and at least one of the first member 6 and the second member 7 may be made up of another form, for example, a block-shaped member.

[0068] In the assembled state where the first member 6 and the second member 7 are assembled (hereinafter sometimes simply referred to as the "assembled state"), they are stacked with their thickness direction oriented along the z-axis, as shown in Figures 3 and 4. In the assembled state, the first member 6 is located on the +z-axis side, and the second member 7 is located on the -z-axis side, with the bottom surface 61 of the first member 6 and the top surface 71 of the second member 7 joined together. In the assembled state, the material supply unit 1 is connected to the first member 6, and the nozzle 22 is connected to the second member 7.

[0069] In the illustrated configuration, the first member 6 and the second member 7 have the same thickness (average thickness), but the present invention is not limited to this and the thicknesses may be different.

[0070] Furthermore, in the assembled state of the first member 6 and the second member 7, they are fixed so that the joined state of the first member 6 and the second member 7, i.e., the assembled state, is maintained. The assembled state can be maintained and fixed by a fixing member (not shown). By releasing the fixation by the fixing member, the assembled state of the first member 6 and the second member 7 can be released, as shown in FIG. 4, and the first member 6 and the second member 7 can be separated, i.e., can be put into a separated state.

[0071] The fixing member is not particularly limited, but examples thereof include clamping members such as clamps that clamp four sides of the outer peripheries (edges) of the first member 6 and the second member 7 shown in Fig. 2, two sides located on the -x-axis side and the +x-axis side, or two sides located on the -y-axis side and the +y-axis side. Preferably, such fixing members are detachable from the first member 6 and the second member 7 and allow easy fixing and release.

[0072] The first member 6 has a main flow path 211 that penetrates in its thickness direction (z-axis direction), a plurality of first grooves 62 that extend perpendicular to the main flow path 211 on the xy plane, communicate with the lower end of the main flow path 211, and open to the lower surface 61 of the first member 6 (the surface facing the second member 7 on the -z-axis side), and a plurality of installation grooves 63 that open to the lower surface 61.

[0073] Four first grooves 62 are formed, each having a semicircular cross section. In the assembled state, the first grooves 62 constitute the branch flow paths 212A, 212B, 212C, and 212D described above, and their positions and shapes as viewed from the z-axis direction are as described above.

[0074] Two installation grooves 63 are formed, each having a semicircular cross section. In an assembled state, the pair of installation grooves 63 become the pair of installation holes 215 in which the first heater 216 described above is installed, and their formation positions and shapes as viewed from the z-axis direction are as described above.

[0075] The second member 7 has a plurality of second grooves 72 that open to the upper surface 71 of the second member 7 (the surface facing the first member 6 on the +z axis side), a plurality of installation grooves 73 that open to the upper surface 71, and the aforementioned second portion 214.

[0076] The second grooves 72 have a semicircular cross section and four of them are formed. In the assembled state, the second grooves 72, together with the corresponding first grooves 62 formed in the first member 6, constitute the branch flow paths 212A, 212B, 212C, and 212D described above, and their positions and shapes as viewed in the z-axis direction are as described above.

[0077] Two installation grooves 73 are formed, each having a semicircular cross section. The pair of installation grooves 73, together with the installation groove 63 of the first member 6, constitute the pair of installation holes 215 in which the above-mentioned first heater 216 is installed, and their formation positions and shapes as viewed from the z-axis direction are as described above.

[0078] When the first member 6 and the second member 7 are assembled, the corresponding first grooves 62 and second grooves 72 come together and overlap in the z-axis direction, forming the first portions 213 of the branch flow paths 212A, 212B, 212C, and 212D.

[0079] Furthermore, when the first member 6 and the second member 7 are separated, the plurality of first grooves 62 that open to the lower surface 61 of the first member 6 are exposed, and the plurality of second grooves 72 that open to the upper surface 71 of the second member 7 are exposed. In the separated state, the first grooves 62 and the second grooves 72 are exposed, which makes it easy to perform maintenance such as cleaning of the first grooves 62 and the second grooves 72, and more specifically, maintenance such as maintenance, inspection, cleaning, polishing, and replacement of all or part of each branch flow path 212 (hereinafter sometimes simply referred to as "maintenance").

[0080] To explain in more detail, when the first member 6 and the second member 7 are assembled, branch channels 212A, 212B, 212C, and 212D are formed at the boundary 8 between the first member 6 and the second member 7, i.e., at the joining surface 81 (the imaginary surface where the lower surface 61 and the upper surface 71 are joined) between the lower surface 61 of the first member 6 and the upper surface 71 of the second member 7. Then, the plasticized modeling material M supplied from the material supply unit 1 is guided through the supply channel 12, the main channel 211, and each branch channel 212 to the internal channel 221 of each nozzle 22, and can be injected from the lower end of each nozzle 22.

[0081] On the other hand, when the first member 6 and the second member 7 are separated, the first grooves 62 and the second grooves 72 are exposed, and the branch flow paths 212A, 212B, 212C, and 212D are open, facilitating maintenance of the branch flow paths 212, their surrounding areas, and other locations. This prevents problems such as clogging of part of the branch flow paths 212, which would hinder the smooth flow of the molding material M, and allows for continued, stable injection of the molding material M. As a result, the quality of the molded products (molding quality) obtained by the injection molding machine 100 can be maintained at a high level.

[0082] In addition, in the separated state, each installation groove 63 and installation groove 73 is exposed, and each installation hole 215 is also open, so that the first heater 216 can be easily attached and detached to the installation hole 215, and maintenance such as cleaning and replacement can be easily performed.

[0083] As described above, in the assembled state, the first groove 62 and the second groove 72 are joined together to form the first portion 213 of the branch flow path 212. In this embodiment, the first groove 62 and the second groove 72 each account for half of the flow path volume of the first portion 213. That is, the volume ratio between the first groove 62 and the second groove 72 is 1:1. However, the present invention is not limited to this, and the flow path volume ratio of the first portion 213 formed by the first groove 62 and the second groove 72 can be any value between 1:100 and 100:1. That is, the first portion 213 may be formed biased toward either the first member 6 or the second member 7.

[0084] The constituent material of the first member 6 and the second member 7 is not particularly limited, but examples thereof include various metal materials such as iron-based alloys such as pre-hardened steel, as-rolled steel, and stainless steel, aluminum or aluminum-based alloys, copper or copper-based alloys, and various ceramic materials. When the first member 6 and the second member 7 are made of a metal material, the metal material may be the same as or different from the material of the mold for the mold portion 3 described above.

[0085] As described above, the injection molding machine 100 comprises a material supply unit 1 that supplies a molding material M containing a plasticized thermoplastic resin, a manifold 21 having a main flow path 211 communicating with the material supply unit 1 and a plurality of branch flow paths 212 branching from the main flow path 211, an injection unit 2 that is connected to each of the branch flow paths 212 and has a plurality of nozzles 22 that inject the molding material M into a mold unit 3, a positioning unit 4 that positions the injection unit 2 and the mold unit 3, and a control unit 5 that controls the operation of the material supply unit 1 and the injection unit 2, and the manifold 21 has a first member 6 and a second member 7 that are separate from each other and can be assembled and separated, and when the first member 6 and the second member 7 are assembled, a branch flow path 212 is formed at the boundary 8 (joint surface 81) of the first member 6 and the second member 7. As a result, when the first member 6 and the second member 7 are assembled, the plasticized molding material M can be transported to each nozzle 22 via the main channel 211 and the branch channel 212 and injected. Meanwhile, by separating the first member 6 and the second member 7, maintenance of the branch channel 212 and the like can be easily performed. This prevents problems such as clogging of part of the branch channel 212 and interruption of the smooth flow of the molding material M, and allows for continuous, stable injection of the molding material M. As a result, the quality of molded products obtained by the injection molding machine 100 can be maintained at a high level.

[0086] As described above, the first portion 213 of the branch flow path 212 formed in the assembled state is shared by the first groove 62 formed in the first member 6 and the second groove 72 formed in the second member 7, at a ratio of 1 / 2 or some other ratio. That is, in this embodiment, elements that become the branch flow path 212 are formed in both the first member 6 and the second member 7. However, the present invention is not limited to this, and the first portion 213 of the branch flow path 212 may be formed in only one of the first member 6 and the second member 7. That is, a configuration may be possible in which the first groove is formed only in the first member 6 and the second groove is not formed in the second member 7, or a configuration may be possible in which the second groove is formed only in the second member 7 and the first groove is not formed in the first member 6. Furthermore, the number, arrangement, etc. of the branch flow paths 212 are not limited to the illustrated configuration.

[0087] The first member 6 and the second member 7 are each plate-shaped and are stacked so that their thickness directions are aligned when assembled. This allows the first member 6 and the second member 7 to be easily assembled and separated, making maintenance easier.

[0088] The first member 6 has a first groove 62 that opens to the boundary portion 8 (lower surface 61), and the second member 7 has a second groove 72 that opens to the boundary portion 8 (upper surface 71), and in an assembled state, the first groove 62 and the second groove 72 form a branch flow path 212. This makes it possible to maximize the cross-sectional area of ​​the branch flow path 212, making maintenance easier.

[0089] While the injection molding machine of the present invention has been described above based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part can be replaced with any configuration having the same function. Also, any other components may be added.

[0090] The molding unit 2 may also have a weight detection unit that detects the weight of the molding material M supplied to the mold unit 3. In this case, the control unit 5 can control the operation of the injection unit 2 based on the detection value of the weight detection unit so that the injection amount of the molding material M from the nozzle 22 is constant.

[0091] The nozzle 22 may have a branched flow path, or a member having a branched flow path may be attached to the nozzle 22 for use.

[0092] Furthermore, the manifold 21 may have a plurality of main flow paths. In this case, the branch flow paths branching from each main flow path may be in communication with each other or may be provided independently. [Explanation of symbols]

[0093] 1...material supply section, 2...injection section, 3...mold section, 4...positioning section, 5...control section, 6...first member, 7...second member, 8...boundary section, 11...supply nozzle, 12...supply flow path, 21...manifold, 22...nozzle, 22A...injection nozzle, 22B...injection nozzle, 22C...injection nozzle, 22D...injection nozzle, 61...lower surface, 62...first groove, 63...installation groove, 71...upper surface, 72...second groove, 73...installation groove, 81...joint surface, 100...injection molding machine, 211...main flow path, 212...branch flow path, 212 A...branch flow path, 212B...branch flow path, 212C...branch flow path, 212D...branch flow path, 213...first part, 214...second part, 215...installation hole, 216...first heater, 217...pressure detection part, 217A...pressure sensor, 217B...pressure sensor, 217C...pressure sensor, 217D...pressure sensor, 218...flow rate adjustment part, 219...insertion hole, 220...rod-shaped member, 221...internal flow path, 222...second heater, 223...temperature sensor, 230...connection part, M...molding material

Claims

1. a material supply unit that supplies a modeling material containing a plasticized thermoplastic resin; a manifold having a main flow path communicating with the material supply unit and a plurality of branch flow paths branching from the main flow path, and an injection unit having a plurality of nozzles connected to each of the branch flow paths and configured to inject the modeling material into a mold portion; a positioning unit that positions the injection unit and the mold unit; a control unit that controls the operation of the material supply unit and the injection unit, the manifold has a first member and a second member that are separate from each other and can be assembled and separated; an injection molding machine, characterized in that, in an assembled state of the first member and the second member, the branch flow path is formed at a boundary between the first member and the second member;

2. 2. The injection molding machine according to claim 1, wherein the first member and the second member are each plate-shaped and are stacked such that their thickness directions coincide with each other in the assembled state.

3. the first member has a first groove that opens to the boundary portion, the second member has a second groove that opens to the boundary portion, 2. The injection molding machine according to claim 1, wherein in the assembled state, the branch flow path is formed by the first groove and the second groove.

4. 2. The injection molding machine according to claim 1, wherein the branch flow paths are arranged radially around the main flow path when viewed in the extending direction of the main flow path.

5. the manifold has a pair of first heaters spaced apart from each other; 5. The injection molding machine according to claim 1, wherein each of the branched flow paths is located between a pair of the first heaters.

6. a flow rate adjusting unit that adjusts the flow rate of the modeling material flowing through each of the branch channels; 5. The injection molding machine according to claim 1, wherein the control unit controls the operation of the flow rate adjusting unit so that the nozzles that are not used among the plurality of nozzles are closed.

7. a pressure detection unit that detects the pressure of the modeling material flowing through each of the branch channels; 5. The injection molding machine according to claim 1, wherein, when the number of nozzles in use changes, the control unit controls the operation of the injection unit so as to perform trial injections until the pressure value measured by the pressure detection unit becomes constant.

8. a temperature sensor that detects the temperature of the modeling material in the nozzle; and a second heater that heats the nozzle; 5. An injection molding machine according to claim 1, wherein the control unit controls the operation of the second heater based on the detected value of the temperature sensor, and adjusts the temperature of the molding material injected from the multiple nozzles.

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