Compounding apparatus and injection molding machine equipped therewith

Abstract

The present invention provides a compounding apparatus that separately provides a plasticizing unit for melting thermoplastic resin and a mixing and kneading unit for mixing reinforcing fibers, and that can smoothly move both units in accordance with the forward and backward movement of the injection device of the injection molding machine body. [Solution] The compounding apparatus X consists of a plasticizing unit 40 that melts thermoplastic resin B and transports it downstream, a mixing and kneading unit 42 provided downstream of the plasticizing unit 40 that mixes the molten thermoplastic resin A with a different mixing material B and transports it to the raw material receiving inlet 72 of the injection unit 44 of the injection molding machine body Y, and a mounting table 80 on which the plasticizing unit 40 and the mixing and kneading unit 42 are placed. The mounting table 80 is provided with a movable mechanism 82 that allows the plasticizing unit 40 and the mixing and kneading unit 42 to move freely in the planar direction.

Description

Technical Field

[0001] The present invention relates to a compounding device for mixing reinforcing fibers into a thermoplastic resin, and an injection molding machine for molding a molded product using the thermoplastic resin mixed with the reinforcing fibers.

Background Art

[0002] Conventionally, a technique has been developed for mixing reinforcing fibers with a thermoplastic resin used for injection molding and supplying the mixture to an injection molding machine (for example, Patent Document 1).

[0003] In the injection molding machine according to Patent Document 1, a resin supply section is provided upstream in one injection cylinder (screw conveyor), and a reinforcing fiber supply section is provided downstream. In the injection cylinder, the thermoplastic resin is kneaded while being compressed, and the aggregate of reinforcing fibers is dispersed in the thermoplastic resin while being defibrated.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when attempting to melt the thermoplastic resin and mix a mixing material different from the thermoplastic resin (for example, reinforcing fibers) in one injection cylinder, problems may occur in the mixing of the thermoplastic resin and the mixing material, such as frequent breakage of the reinforcing fibers, making it difficult to achieve the desired strength of the molded product.

[0006] To address this problem, if a plasticizing unit for melting thermoplastic resin and a mixing and kneading unit for mixing the admixture are provided separately, these plasticizing and mixing and kneading units would be arranged side by side on the injection molding machine body. In this case, if they are not arranged parallel to the forward and backward movement of the injection device on the injection molding machine body so that they can move smoothly, there is a risk of damage to the joint between the outlet of the mixing and kneading unit and the raw material inlet of the injection molding machine body. However, there is a problem in that it is difficult to arrange them in parallel in this way so that the plasticizing and mixing and kneading units can move smoothly.

[0007] The present invention has been made in view of these problems, and its objective is to provide a compounding device that separately provides a plasticizing unit for melting a thermoplastic resin and a mixing and kneading unit for mixing a mixture, and that can smoothly move both units in accordance with the forward and backward movement of the injection device of the injection molding machine body, and an injection molding machine equipped therewith. [Means for solving the problem]

[0008] According to one aspect of the present invention, A plasticizing unit that melts thermoplastic resin and transports it downstream, A mixing and kneading unit is provided downstream of the plasticizing unit and mixes a different mixing material with the molten thermoplastic resin and conveys it to the raw material receiving port of the injection unit of the injection molding machine body. The system comprises a plasticizing unit and a mounting platform on which the mixing and kneading unit is placed, The mounting platform is equipped with a movable mechanism that allows the plasticizing unit and the mixing and kneading unit to move freely in the planar direction. A compounding device is provided.

[0009] Preferably, The aforementioned movable mechanism is A parallel guide moves the plasticizing unit and the mixing and kneading unit in a direction parallel to the direction in which the injection molding machine body extends, The system includes orthogonal guides that move the plasticizing unit and the mixing and kneading unit in a direction perpendicular to the parallel guides.

[0010] Preferably, The plasticizing unit is positioned diagonally with respect to the direction in which the injection molding machine body extends.

[0011] Preferably, The plasticizing unit and the mixing and kneading unit are connected and fixed to each other so as to form a single unit.

[0012] According to another aspect of the present invention, The compounding apparatus and, It is equipped with an injection molding machine body, The injection unit of the injection molding machine body has a raw material receiving port for receiving the molten thermoplastic resin containing the mixed material supplied from the compounding device. An injection molding machine is provided. [Effects of the Invention]

[0013] According to the compounding apparatus of the present invention, a plasticizing unit for melting a thermoplastic resin and a mixing and kneading unit for mixing a different admixture with the molten thermoplastic resin are provided separately. This prevents problems from occurring during the mixing of the thermoplastic resin and the admixture, and makes it possible to obtain a molded product with the desired strength.

[0014] In addition, the mounting platform on which the plasticizing unit and the mixing and kneading unit are placed is equipped with a movable mechanism that allows the plasticizing unit and the mixing and kneading unit to move freely in the planar direction, so that both units can move smoothly in accordance with the forward and backward movement of the injection unit of the injection molding machine body. [Brief explanation of the drawing]

[0015] [Figure 1] This figure schematically shows an example of an injection molding machine 10 according to an embodiment. [Figure 2] It is a diagram schematically showing an example of an injection device 14 according to an embodiment. [Figure 3] It is a top view showing an example of an injection molding machine 10 according to an embodiment. [Figure 4] It is an enlarged top view showing an example of a compound device X according to an embodiment.

Mode for Carrying Out the Invention

[0016] (Configuration of Injection Molding Machine 10) The injection molding machine 10 according to the present embodiment is a machine that repeats a molding cycle such as mold closing, mold clamping, injection filling of molten resin, metering, mold opening, and taking out of a molded product to mold a molded product. As shown in FIG. 1, roughly, it includes a mold clamping device 12, an injection device 14, and a control device 15.

[0017] The mold clamping device 12 includes a machine base 16, a fixed platen 18, a movable platen 20, a pressure receiving platen 22, tie bars 24, and a toggle mechanism 26.

[0018] The machine base 16 is a member that constitutes the mold clamping device 12 and a member that serves as a base for the injection device 14.

[0019] The fixed platen 18 is fixed on the machine base 16, and a fixed mold 30 that constitutes the mold 28 is attached.

[0020] The movable platen 20 is a member that slides on the machine base 16 so as to approach and separate from the fixed platen 18, and a movable mold 33 that constitutes the mold 28 is attached. When the movable mold 33 contacts the fixed mold 30, a cavity Z into which molten resin is filled is formed

[0021] The pressure receiving platen 22 is a member fixed on the machine base 16 on the side opposite to the fixed platen 18 as viewed from the movable platen 20.

[0022] The tie bar 24 is a round bar-shaped member with one end fixed to the fixed platen 18 and the other end fixed to the pressure receiving platen 22. The tie bar 24 is inserted through a tie bar insertion hole 31 formed in the movable platen 20, which is positioned between the fixed platen 18 and the pressure receiving platen 22. This allows the movable platen 20 to slide along the tie bar 24 on the machine base 16 in the left-right direction in the figure. Note that multiple tie bars 24 (for example, four) are used.

[0023] The toggle mechanism 26 is a mechanism for moving the movable platen 20 closer to or further away from the fixed platen 18, and the clamping drive device 32 is attached to the pressure receiving platen 22.

[0024] The movable platen 20 moves along the tie bar 24 (moved left and right in the figure) as the driving force of the mold clamping drive device 32 is transmitted through the toggle mechanism 26. When the movable platen 20 moves to the left, the fixed mold 30 and the movable mold 33 separate. On the other hand, when the movable platen 20 moves to the right, the fixed mold 30 and the movable mold 33 come into contact, forming a cavity Z (internal space) inside the mold 28. Then, when further pressure is applied in the direction that moves the movable platen 20 to the right, the fixed mold 30 and the movable mold 33 are clamped together.

[0025] The injection device 14 is a device that injects and fills molten resin into the cavity Z in the mold 28 formed when the movable mold 33 comes into contact with the fixed mold 30. As shown in Figure 2, it consists of a compounding device X including a plasticizing unit 40 and a mixing and kneading unit 42, an injection unit 44, and a mounting table 80.

[0026] In this embodiment, the injection molding machine body Y is composed of the mold clamping device 12 and the injection unit 44 described above, and is mounted on the machine base 16.

[0027] The plasticizing unit 40 has the role of bringing the supplied thermoplastic resin A into a completely molten state, and includes a heating cylinder 46, a plasticizing screw 48, a heater 50, a thermoplastic resin receiving port 52, a thermoplastic resin discharge port 54, and a plasticizing screw operating mechanism 55.

[0028] The heating cylinder 46 is a cylindrical member, with a thermoplastic resin receiving port 52 formed at one end (upstream side: right side in the figure) and a thermoplastic resin outlet 54 formed at the other end (downstream side: left side in the figure) through which the molten thermoplastic resin A is discharged.

[0029] The plasticizing screw 48 is located inside the heating cylinder 46 and has the role of transporting the thermoplastic resin A received from the thermoplastic resin receiving port 52 to the thermoplastic resin discharge port 54.

[0030] The heater 50 is a heat source positioned on the outer circumference of the heating cylinder 46. The heat from this heater 50 and the plasticizing screw 48 cause the thermoplastic resin A inside the heating cylinder 46 to become completely molten.

[0031] Throughout this specification, "completely molten state" refers to a state in which there are absolutely no solid particles in the molten resin.

[0032] The plasticizing screw operating mechanism 55 rotates the plasticizing screw 48.

[0033] The mixing and kneading unit 42 receives the thermoplastic resin A, which has been completely molten in the plasticizing unit 40, and also receives the reinforcing fibers B. It has the role of heating and mixing the thermoplastic resin A and the reinforcing fibers B, and includes a heating cylinder 56, a mixing and kneading screw 58, a heater 60, a molten thermoplastic resin receiving port 62, a reinforcing fiber receiving port 63, a raw material discharge port 64, and a mixing and kneading screw operating mechanism 65.

[0034] The heating cylinder 56 is a cylindrical member, with a molten thermoplastic resin inlet 62 and a reinforcing fiber inlet 63 formed at one end (upstream side: upper side in the figure), and a raw material discharge port 64 formed at the other end (downstream side: lower side in the figure) through which the mixed paste (raw material) of molten thermoplastic resin A and reinforcing fiber B is discharged.

[0035] The mixing and kneading screw 58 is located inside the heating cylinder 56 and has the role of conveying the thermoplastic resin A received from the molten thermoplastic resin receiving port 62 and the reinforcing fiber B received from the reinforcing fiber receiving port 63 to the raw material discharge port 64 while mixing and kneading them.

[0036] The heater 60 is a heat source positioned on the outer circumference of the heating cylinder 56. The heat from this heater 60 maintains the complete molten state of the thermoplastic resin A inside the heating cylinder 56.

[0037] The mixing and kneading screw operating mechanism 65 rotates the mixing and kneading screw 58.

[0038] The injection unit 44 has the role of further kneading the mixed thermoplastic resin A and reinforcing fiber B and injecting them into the cavity Z of the clamping device 12, and includes a heating cylinder 66, a kneading injection screw 68, a heater 70, a raw material receiving port 72, a raw material injection port 74, and a kneading injection screw operating mechanism 75.

[0039] The heating cylinder 66 is a cylindrical member, with a raw material receiving port 72 formed at one end (upstream side: right side in the figure) for receiving a mixture (raw material) of molten thermoplastic resin A and reinforcing fiber B, and a raw material injection port 74 formed at the other end (downstream side: left side in the figure) for injecting the raw material toward the clamping device 12.

[0040] The kneading injection screw 68 is located inside the heating cylinder 66 and is responsible for kneading and dispersing the raw material received from the raw material receiving port 72, as well as measuring and injecting it from the raw material injection port 74.

[0041] The heater 70 is a heat source positioned on the outer circumference of the heating cylinder 66. The heat from this heater 70 maintains the complete molten state of the thermoplastic resin A inside the heating cylinder 66.

[0042] The mixing injection screw operating mechanism 75 rotates the mixing injection screw 68 to mix and disperse the raw materials (thermoplastic resin A and reinforcing fiber B) within the injection unit 44. In addition, the mixing injection screw operating mechanism 75 also measures the raw materials and injects them by moving the mixing injection screw 68 forward and backward.

[0043] The mounting platform 80 is a platform on which the plasticizing unit 40 and the mixing and kneading unit 42 are placed, and is equipped with a movable mechanism 82 that allows the plasticizing unit 40 and the mixing and kneading unit 42 to move freely in the planar direction.

[0044] As shown in Figures 3 and 4, the movable mechanism 82 has a parallel guide 84 that moves the plasticizing unit 40 and the mixing and kneading unit 42 in a direction parallel to the direction in which the injection molding machine body Y extends, and an orthogonal guide 86 that moves the plasticizing unit 40 and the mixing and kneading unit 42 in a direction perpendicular to the parallel guide 84. Of course, the movable mechanism 82 may be formed with a configuration different from that of the parallel guide 84 and the orthogonal guide 86.

[0045] In this embodiment, so-called straight guides are used for the parallel guide 84 and the orthogonal guide 86, but the types of guides 84 and 86 are not limited to these. Also, the plasticizing unit 40 and the mixing and kneading unit 42 are respectively placed on a pair of orthogonal guides 86 which are placed on a common parallel guide 84, but different types of parallel guides 84 and 86 may be used for each of the two guides 84 and 86.

[0046] Furthermore, in this embodiment, the plasticizing unit 40 and the mixing and kneading unit 42 are connected and fixed together by an L-shaped integrated member 88 so as to be an integral part of each other.

[0047] By connecting and fixing the plasticizing unit 40 and the mixing and kneading unit 42 with an integrated member 88, as described later, when the mixing and kneading unit 42 moves in accordance with the forward and backward movement of the injection unit 44, it is possible to move the plasticizing unit 40 and the mixing and kneading unit 42 as a single unit while avoiding the application of unwanted stress to the thermoplastic resin discharge port 54 and the molten thermoplastic resin receiving port 62, which are the joints between the mixing and kneading unit 42 and the plasticizing unit 40.

[0048] Furthermore, in this embodiment, the plasticizing unit 40 is positioned diagonally with respect to the direction in which the injection molding machine body Y extends. Throughout this specification, "positioned diagonally" means that the direction in which the plasticizing unit 40 extends is parallel to the direction in which the injection molding machine body Y extends, or at an angle other than 90°.

[0049] By arranging the plasticizing unit 40 diagonally with respect to the direction in which the injection molding machine body Y extends, the space required for arranging the plasticizing unit 40 and the mixing and kneading unit 42 can be made smaller.

[0050] The control device 15 controls the entire molding cycle by the injection molding machine 10, but below we will only describe the control of the injection device 14 by the control device 15.

[0051] (Procedure for injection molding using the injection molding machine 10 according to the embodiment) Next, we will explain the procedure for injection molding a molded product using the injection molding machine 10 according to the above embodiment, focusing on the injection of raw material into the cavity Z by the injection device 14.

[0052] The plasticizing unit 40, the mixing and kneading unit 42, and the injection unit 44, which constitute the injection device 14, are heated to a predetermined temperature using heaters 50, 60, and 70, respectively.

[0053] At this time, the heating cylinders 46, 56, and 66 of the plasticizing unit 40, the mixing and kneading unit 42, and the injection unit 44 expand due to thermal expansion as they are heated by heaters 50, 60, and 70.

[0054] As the heating cylinder 66 of the injection unit 44 extends, the position of the raw material receiving inlet 72 moves, and consequently, the mixing and kneading unit 42 also moves due to the movable mechanism 82. Furthermore, the plasticizing unit 40, which is integrated with the mixing and kneading unit 42 by an integrated member 88, also moves due to the movable mechanism 82.

[0055] Subsequently, pelletized thermoplastic resin A is introduced into the thermoplastic resin receiving port 52 of the plasticizing unit 40.

[0056] The thermoplastic resin A that is introduced is transported by the plasticizing screw 48 towards the thermoplastic resin discharge port 54 of the plasticizing unit 40, and during transport, it is completely melted by the heat from the heater 50 and the plasticizing screw 48.

[0057] The thermoplastic resin A, which has reached a completely molten state, is discharged from the thermoplastic resin discharge port 54 and then supplied to the mixing and kneading unit 42 from the molten thermoplastic resin receiving port 62. At the same time, the reinforcing fibers B are also supplied to the mixing and kneading unit 42 from the reinforcing fiber receiving port 63.

[0058] The types of reinforcing fibers B supplied to the mixing and kneading unit 42 include glass fibers, carbon fibers, and natural fibers.

[0059] The reinforcing fibers B supplied to the mixing and kneading unit 42 are mixed with the thermoplastic resin A, which has reached a completely molten state, by the mixing and kneading screw 58 and transported toward the raw material discharge port 64. During this transport, the thermoplastic resin A is maintained in a completely molten state by the heat from the heater 60.

[0060] The raw material (a mixture of thermoplastic resin A and reinforcing fiber B) discharged from the raw material discharge port 64 is supplied to the injection unit 44 from the raw material receiving port 72. The raw material is kneaded and dispersed within the injection unit 44, and then metered before being injected from the raw material injection port 74 into the cavity Z of the clamping device 12.

[0061] The raw material injected into cavity Z is cooled within cavity Z and cast as a molded body. The completed molded body is removed when the mold 28 is opened.

[0062] (Features of injection molding machine 10) According to the compounding apparatus X of this embodiment, a plasticizing unit 40 for melting the thermoplastic resin A and a mixing and kneading unit 42 for mixing reinforcing fibers B into the molten thermoplastic resin A are provided separately. This prevents frequent breakage of the reinforcing fibers B when they come into contact with the thermoplastic resin A in an incompletely molten state, and makes it possible to obtain a molded product with the desired strength.

[0063] In addition, the mounting base 80 on which the plasticizing unit 40 and the mixing and kneading unit 42 are placed is equipped with a movable mechanism 82 that allows the plasticizing unit 40 and the mixing and kneading unit 42 to move freely in the planar direction, so that both units 40 and 42 can move smoothly in accordance with the forward and backward movement of the injection unit 44 of the injection molding machine body Y.

[0064] (Variation 1) In the compounding apparatus X according to the above embodiment, reinforcing fibers B were placed in the mixing and kneading unit 42 and mixed with the molten thermoplastic resin A. However, wood powder C may be mixed instead of reinforcing fibers B.

[0065] In other words, the mixing and kneading unit 42 receives the thermoplastic resin A, which has been completely molten in the plasticizing unit 40, and also receives the wood powder C, and has the role of mixing and kneading the thermoplastic resin A and the wood powder C while heating them. Accordingly, the reinforcing fiber receiving port 63 becomes the wood powder receiving port 63. The wood powder C is not particularly limited as long as it is fibrous.

[0066] (Modification 2) Alternatively, recycled material D may be mixed into the mixing and kneading unit 42 instead of reinforcing fiber B or wood flour C.

[0067] In other words, the mixing and kneading unit 42 receives the thermoplastic resin A, which has been completely molten in the plasticizing unit 40, and also receives the recycled material D, and has the role of mixing and kneading the thermoplastic resin A and the recycled material D while heating them. Accordingly, the reinforcing fiber receiving port 63 becomes the recycled material receiving port 63. Note that the recycled material D may be a different thermoplastic resin that melts differently from the thermoplastic resin A, or it may be a material that does not contain fibers.

[0068] In this specification, materials that are mixed with the thermoplastic resin A in the mixing and kneading unit 42, such as reinforcing fiber B, wood powder C, and recycled material D, are collectively referred to as "mixtures different from thermoplastic resin A."

[0069] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of symbols]

[0070] 10…Injection molding machine, 12…Clamping device, 14…Injection device, 15…Control device, 16…Machine base, 18…Fixed platen, 20…Movable platen, 22…Pressure receiving platen, 24…Tie bar, 26…Toggle mechanism, 28…Mold, 30…Fixed mold, 31…Tie bar insertion hole, 32…Clamping drive device, 33…Movable mold 40...Plasticizing unit, 42...Mixing and kneading unit, 44...Injection unit, 46...Heating cylinder, 48...Plasticizing screw, 50...Heater, 52...Thermoplastic resin inlet, 54...Thermoplastic resin outlet, 55...Plasticizing screw operating mechanism, 56...Heating cylinder, 58...Mixing and kneading screw, 60...Heater, 62...Molten thermoplastic resin inlet, 63...Reinforcement fiber inlet, 64...Raw material outlet, 65...Mixing and kneading screw operating mechanism, 66...Heating cylinder, 68...Kneading injection screw, 70...Heater, 72...Raw material inlet, 74...Raw material injection outlet, 75...Kneading injection screw operating mechanism 80…Mounting platform, 82…Movable mechanism, 84…Parallel guide, 86…Orthogonal guide, 88…Integrated member Z...Cavity, A...Thermoplastic resin, B...Reinforcement fiber, X...Compounding device, Y...Injection molding machine body

Claims

1. A plasticizing unit that melts thermoplastic resin and transports it downstream, A mixing and kneading unit is provided downstream of the plasticizing unit and mixes a different mixing material with the molten thermoplastic resin and conveys it to the raw material receiving port of the injection unit of the injection molding machine body. The system comprises a plasticizing unit and a mounting platform on which the mixing and kneading unit is placed, The mounting platform is equipped with a movable mechanism that allows the plasticizing unit and the mixing and kneading unit to move freely in the planar direction. Compounding device.

2. The aforementioned movable mechanism is A parallel guide moves the plasticizing unit and the mixing and kneading unit in a direction parallel to the direction in which the injection molding machine body extends, The system includes orthogonal guides that move the plasticizing unit and the mixing and kneading unit in a direction perpendicular to the parallel guides. The compounding apparatus according to claim 1.

3. The plasticizing unit is positioned diagonally with respect to the direction in which the injection molding machine body extends. The compounding apparatus according to claim 1.

4. The plasticizing unit and the mixing and kneading unit are connected and fixed to each other so as to be an integral part of one another. The compounding apparatus according to claim 1.

5. A compounding apparatus according to any one of claims 1 to 4, It is equipped with an injection molding machine body, The injection unit of the injection molding machine body has a raw material receiving port for receiving the molten thermoplastic resin containing the mixed material supplied from the compounding device. Injection molding machine.

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