Injection molding machine and injection molding system

Abstract

To move the injection device of an injection molding machine in the direction separating from a mold in such a state that a connection pipe for directly inputting an output molten resin to the injection molding machine is fixed.SOLUTION: The injection molding machine 10 includes the heating cylinder 12 that has the long hole 125 into which the molten resin output from the output port 32 of the connecting pipe 30, which is a pipe in which the position of the output port 32 is fixed, can be input and that heats the molten resin input from the long hole 125, and the injection molding machine 10 is a pipe-shaped member that is fixed to the output port 32 of the connecting pipe 30 and in which the heating cylinder 12 is disposed so as to be movable in the center line direction. And a sleeve member 40 having a through-hole 41 for passing the molten resin output from the output port 32 toward the long hole 125 of the heating cylinder 12, wherein the output port 32 of the connecting pipe 30 and the long hole 125 of the heating cylinder 12 face each other as long as the heating cylinder 12 moves within a predetermined distance range in the center line direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In order to directly input the molten resin output from a device that decontaminates contaminants contained within the resin to be recycled into an injection molding machine that performs injection molding using the molten resin as a material, the device that outputs the molten resin and the injection molding machine are sometimes connected by piping.In this case, in order to absorb positional movement that occurs due to purging operations and the like of the injection unit of the injection molding machine, for example, a connecting pipe that includes a sleeve-type expansion joint that serves as a piping joint may be provided (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 056618 Summary of the Invention [Problem to be solved by the invention]

[0004] When a connecting pipe including a sleeve-type expansion joint is installed, the sleeve slides in accordance with the movement of the injection device, moving back and forth between the inside and outside of the pipe. As a result, the molten resin passing through the inside of the pipe may adhere to the surface of the sleeve and become exposed to the outside of the pipe. In this case, the sliding of the sleeve may cause the exposed molten resin to rub against each other and carbonize, potentially contaminating the molten resin as solid foreign matter. To address this issue, when performing a purging operation or the like of the injection device, the injection device may be moved away from the mold to form a predetermined space between the injection device and the mold.

[0005] The object of the present invention is to enable the injection unit of an injection molding machine to be moved away from the mold while the connecting pipe for directly inputting the output molten resin into the injection molding machine is fixed. [Means for solving the problem]

[0006] The injection molding machine of the present invention, which was completed with this objective in mind, comprises a heating cylinder having a long hole into which molten resin output from a pipe having a fixed output port can be input, and which heats the molten resin input from the long hole; and a sleeve member fixed to the output port of the pipe, which is a tubular member inside which the heating cylinder is arranged so that it can move in the centerline direction, and which has a through hole that allows the molten resin output from the output port to pass toward the long hole of the heating cylinder, and is characterized in that the output port of the pipe and the long hole of the heating cylinder are opposed to each other as long as the heating cylinder moves within a predetermined distance in the centerline direction. Here, the length of the elongated hole of the heating cylinder in the center line direction may be longer than the predetermined distance. The elongated hole of the heating cylinder may be covered by the sleeve member. The heating cylinder may further include a seal member disposed inside both ends of the sleeve member to seal a gap between the sleeve member and the heating cylinder. Furthermore, the injection molding system of the present invention, which has been completed with the above object in mind, is an injection molding system characterized by including: a heating cylinder having a long hole into which molten resin output from a pipe having a fixed output port can be input, and which heats the molten resin input from the long hole; a sleeve member fixed to the output port of the pipe and having the heating cylinder disposed therein so as to be movable in a centerline direction, the sleeve member having a through hole through which the molten resin output from the output port passes toward the long hole of the heating cylinder; an injection molding machine in which the output port of the pipe and the long hole of the heating cylinder face each other as long as the heating cylinder moves within a predetermined distance in the centerline direction; an output device that outputs the molten resin; and a connecting pipe that connects the output device to the injection molding machine and through which the molten resin output from the output device flows toward the injection molding machine. [Effects of the Invention]

[0007] According to the present invention, the injection unit of the injection molding machine can be moved away from the mold while the connecting pipe for directly inputting the output molten resin into the injection molding machine is fixed. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing an example of the overall configuration of an injection molding system according to an embodiment of the present invention; [Figure 2] 2 is a diagram showing a state of a purge operation of an injection unit of an injection molding machine that constitutes the injection molding system of FIG. 1. FIG. [Figure 3] 5A and 5B are diagrams illustrating an example of the configuration of a sleeve member. [Figure 4] 5A and 5B are diagrams illustrating an example of the configuration of a sleeve member. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. <Configuration of Injection Molding System 1> FIG. 1 is a diagram showing an example of the overall configuration of an injection molding system 1 according to this embodiment. 1 is a system configured to include an injection molding machine 10 that performs injection molding using molten resin, an output device 20 that outputs the molten resin toward the injection molding machine 10, and a connecting pipe 30 that connects the output device 20 to the injection molding machine 10. In the injection molding system 1, the molten resin is output from the output device 20 toward the injection molding machine 10, so the injection molding machine 10 is a device located downstream from the output device 20.

[0010] The injection molding machine 10 and the output device 20 are connected by a connecting pipe 30. The connecting pipe 30 is a bent metal pipe having a space 31 formed therein that serves as a flow path for the molten resin. Therefore, the connecting pipe 30 has the heat resistance and pressure resistance required for the flow of the molten resin. Furthermore, the inner surface of the connecting pipe 30 is smooth, providing a structure that prevents the molten resin from accumulating. The upstream end of the connecting pipe 30 is connected to the output device 20, and the downstream end of the connecting pipe 30 is connected to the injection molding machine 10. Therefore, as shown by the arrows in FIG. 1 , the molten resin output from the output device 20 flows through the connecting pipe 30 and is input to the injection molding machine 10.

[0011] (injection molding machine 10) The injection molding machine 10 is a molding machine used to manufacture molded articles using molten resin as a material. The injection molding machine 10 is connected to the output device 20 via a connecting pipe 30, and is therefore able to receive the molten resin output from the output device 20 and manufacture molded articles using the molten resin as a material.

[0012] The injection molding machine 10 includes an injection device 11 that heats molten resin, which is the material, and injects it into the inside of a mold 50. The injection device 11 includes a heating cylinder 12 that heats the molten resin and delivers the required amount of molten resin, and an injection cylinder 13 that injects the molten resin delivered from the heating cylinder 12 into the inside of the mold 50.

[0013] The heating cylinder 12 has an elongated hole 125 into which the molten resin output from the output port 32 of the connecting pipe 30 can be introduced. The elongated hole 125 is an oval or rectangular through-hole that is long in the centerline direction. The elongated hole 125 is entirely covered by a cylindrical sleeve member 40 that is arranged radially outward of the heating cylinder 12, and therefore cannot be seen from the outside.

[0014] The sleeve member 40 is a member that allows the heating cylinder 12, which is arranged radially inside, to move in the center line direction. The sleeve member 40 is fixed in position while connected to the end of the connecting pipe 30. There are no particular limitations on the method for connecting the sleeve member 40 to the end of the connecting pipe 30. For example, it may be fixed with a bolt or by welding.

[0015] The sleeve member 40 has a through hole 41 formed therein, which allows the molten resin output from the output port 32 at the end of the connecting pipe 30 to pass toward the long hole 125 of the heating cylinder 12. Therefore, the molten resin output from the output port 32 at the end of the connecting pipe 30 passes through the through hole 41 of the sleeve member 40 and the long hole 125 of the heating cylinder 12, and is input into the inside of the heating cylinder 12.

[0016] The through hole 41 of the sleeve member 40, whose position is fixed by being connected to the output port 32 at the end of the connecting pipe 30, and the long hole 125 of the heating cylinder 12, which allows movement in the centerline direction inside the radial direction of the sleeve member 40, are configured to always be in an opposing positional relationship. In other words, as long as the heating cylinder 12 moves within a predetermined distance in the centerline direction, the output port 32 at the end of the connecting pipe 30 and the long hole 125 of the heating cylinder 12 will always be in an opposing positional relationship.

[0017] Here, the "predetermined distance" is a distance shorter than the length of the elongated hole 125 of the heating cylinder 12 in the centerline direction, and specifically corresponds to the distance by which the injection device 11 is moved in the centerline direction. As a result, the molten resin that is output from the output port 32 and passes through the through hole 41 passes through the elongated hole 125 of the heating cylinder 12 and is input into the inside of the heating cylinder 12, regardless of the position in the centerline direction of the heating cylinder 12 that moves inside the sleeve member 40.

[0018] A sealing member 42 such as a rubber packing capable of sealing the gap between the sleeve member 40 and the heating cylinder 12 is disposed inside both end portions of the sleeve member 40 in the center line direction. The sealing member 42 is a member that seals the gap between the sleeve member 40 and the heating cylinder 12. For example, a configuration may be adopted in which a groove extending in the circumferential direction is provided on the inner wall of both end portions of the sleeve member 40 in the center line direction, and a part of the sealing member 42 is embedded in the groove.

[0019] The sealing members 42 are disposed inside both ends of the sleeve member 40 in the centerline direction, thereby preventing the molten resin from leaking to the outside through the gap between the sleeve member 40 and the heating cylinder 12. The sealing members 42 also function like a wiper due to the sliding of the heating cylinder 12, and therefore, for example, also serve to return molten resin that overflows from the elongated hole 125 and is about to leak out of the sleeve member 40 back to the elongated hole 125. The sealing members 42 also prevent foreign matter from entering from the outside. Furthermore, the intrusion of air from the outside is also prevented, preventing the molten resin inside the sleeve member 40 from coming into contact with air. As a result, deterioration of the molten resin is suppressed.

[0020] The heating cylinder 12 has a screw 121 that heats the molten resin input through the elongated hole 125, and a band heater 122 that heats the heating cylinder 12. The heating cylinder 12 heats the molten resin using shear heat generated by the rotation of the screw 121 and heat emitted from the band heater 122. The band heater 122 is configured, for example, as a lightweight, thin, cylindrical heater made of nichrome wire insulated with a heat-resistant mica plate and exteriorly covered with a stainless steel plate, and is arranged on the outer circumferential surface of the heating cylinder 12.

[0021] At the downstream end of the heating cylinder 12 in the centerline direction, a pipe 123 is arranged for sending the molten resin heated by the heating cylinder 12 toward the injection cylinder 13. The pipe 123 is a metal pipe with a bent portion, and a space 124 is formed inside to serve as a flow path for the molten resin. Therefore, the pipe 123 has the heat resistance and pressure resistance required for the molten resin to flow. Furthermore, the inner surface of the pipe 123 is smooth, providing a structure that prevents molten resin from remaining inside.

[0022] The injection cylinder 13 includes a plunger 131 that pressurizes the molten resin sent from the heating cylinder 12 through the piping 123 toward the downstream side in the center line direction, and an injection port 132 for injecting the pressurized molten resin into the inside of the mold 50. The injection device 11 injects the molten resin in the injection cylinder 13 with the injection port 132 in contact with the inlet 52 of the sprue 51, which is a flow path through which the molten resin flows into the inside of the mold 50.

[0023] According to the injection device 11 having the above configuration, the entire injection device 11 can be moved away from the mold 50 while the connecting pipe 30 for directly inputting the molten resin output from the output device 20 into the heating cylinder 12 is fixed. For example, by moving the entire injection device 11 away from the mold 50, a purging operation of the injection device 11 can be performed. The purging operation of the injection device 11 will be described later with reference to FIG. 2.

[0024] (output device 20) The output device 20 is a device that outputs molten resin. The output device 20 decontaminates contaminants contained inside the resin of PET bottles or the like to be recycled by, for example, mechanical recycling (physical recycling method) or chemical recycling (chemical recycling method), and outputs the decontaminated resin as molten resin. The output device 20 is connected to a connecting pipe 30, and its position is fixed together with the connecting pipe 30. The molten resin output from the output device 20 is input to the injection molding machine 10 via the connecting pipe 30.

[0025] Here, "mechanical recycling" refers to a series of processes, such as exposing the resin of collected used PET bottles and the like to high temperatures to turn it into molten resin, and then decontaminating the contaminants remaining inside by diffusing them into the vacuum inside the output device 20. Also, "chemical recycling" refers to a series of processes, such as sorting, chemically decomposing, and repolymerizing the resin of collected used PET bottles and the like to decontaminate the contaminants.

[0026] (Mold 50) The mold 50 molds the molten resin inside by opening and closing the mold, and then cools and solidifies it to complete a molded product (for example, a product or a preform for a product). The opening and closing operations of the mold 50 are performed by a mold clamping device (not shown).

[0027] <Purge Operation of Injection Unit 11> FIG. 2 is a diagram showing the purging operation of the injection unit 11 of the injection molding machine 10 that constitutes the injection molding system 1 of FIG. Carbonized matter accumulates inside the injection unit 11 of the injection molding machine 10. Carbonized matter accumulation is a phenomenon in which molten resin input into the injection unit 11 accumulates, burns, and carbonizes, accumulating on the screw 121 inside the heating cylinder 12. When carbonized matter accumulates, the accumulated carbonized matter peels off, causing molding defects. For this reason, in order to eliminate carbonized matter accumulation, the injection unit 11 periodically performs a purging operation, which is an operation of squeezing and discharging deteriorated molten resin and carbonized matter from the injection cylinder 13 to the outside.

[0028] In order for the injection unit 11 to perform a purge operation, it is necessary to secure a space between the injection cylinder 13 and the mold 50 for the purge operation. For this purpose, the space is secured, for example, by moving the entire injection unit 11 upstream in the center line direction by a distance d. The distance d is not particularly limited. It is sufficient to secure a space in which the entire injection unit 11 can be moved upstream in the center line direction to perform a purge operation, so the distance d is approximately several centimeters to several tens of centimeters.

[0029] Because the position of the output device 20 is fixed, conventionally, a sleeve is provided in a part of the connecting pipe connecting the output device 20 and the injection device, and the movement of the injection device by the distance d is absorbed by sliding the sleeve by the distance d. However, as described above, when the sleeve of the connecting pipe slides, the molten resin exposed to the outside may carbonize and become solid foreign matter and mix with the molten resin inside the connecting pipe.

[0030] In contrast, in the injection molding system 1 according to this embodiment, the connecting pipe 30 connecting the output device 20 and the injection device 11 is a metal pipe with a bent portion as described above, and does not have a sleeve like a conventional connecting pipe. Therefore, the positional relationship between the upstream end (the portion connecting to the output device 20) of the connecting pipe 30 and the downstream end (the portion connecting to the heating cylinder 12) is fixed. In contrast, the injection device 11 allows the heating cylinder 12 to move in the centerline direction by a sleeve member 40 arranged radially outward of the heating cylinder 12. As a result, by moving the entire injection device 11 upstream in the centerline direction by a distance d, a space for performing a purging operation can be secured between the injection cylinder 13 and the mold 50.

[0031] <Configuration of sleeve member 40> 3 and 4 are diagrams showing an example of the configuration of the sleeve member 40. Note that Fig. 3 and Fig. 4 are diagrams showing the heating cylinder 12 as viewed in the direction in which molten resin is output from the connecting pipe 30 toward the heating cylinder 12. Fig. 3 shows the state of the sleeve member 40 when the injection port 132 of the injection device 11 in Fig. 1 is in contact with the mold 50. Fig. 4 shows the state of the sleeve member 40 when the injection port 132 of the injection device 11 in Fig. 2 is separated from the mold 50 and a purge operation is being performed.

[0032] 1, when the injection port 132 of the injection unit 11 is in contact with the mold 50, the entire injection unit 11 is shifted downstream in the center line direction. Therefore, the positional relationship of the output port 32 of the connecting pipe 30 connected to the sleeve member 40 with the elongated hole 125 is shifted upstream in the center line direction, as shown in FIG.

[0033] 2, when the injection port 132 of the injection unit 11 and the mold 50 are separated and the purging operation is being performed, the entire injection unit 11 is shifted to the upstream side in the center line direction. Therefore, the positional relationship of the output port 32 of the connecting pipe 30 connected to the sleeve member 40 with the elongated hole 125 is shifted to the downstream side in the center line direction, as shown in FIG.

[0034] <Modification> As described above, the injection device 11 according to this embodiment is a so-called pre-plunger type (also called a pre-plastication type) injection device that combines the independent heating cylinder 12 and injection cylinder 13. Therefore, the axis of the heating cylinder 12 in the center line direction and the axis of the injection cylinder 13 in the center line direction are not coaxial. However, the pre-plunger type injection device 11 is merely an example. For example, the injection device may be an in-line screw type injection device in which the screw and injection cylinder are coaxial and the molten resin is heated and injected coaxially. In this case, as in the above-described embodiment, a long hole is formed in part of the cylinder of the in-line screw type injection device, and a cylindrical sleeve member is disposed to cover the long hole. When the cylinder moves inside the sleeve member in the center line direction, the injection device as a whole also moves in the center line direction.

[0035] Furthermore, in this embodiment, sealing members 42 such as rubber packings are disposed inside both end portions of the sleeve member 40 in the center line direction, but a configuration without sealing members 42 is also possible. In this case, by preventing the inside of the sleeve member 40 from becoming a negative pressure, it is possible to prevent foreign matter from entering from the outside, but this also makes it easier for molten resin to leak outward from the gap between the sleeve member 40 and the heating cylinder 12. For this reason, the molten resin leaking outward through the gap between the sleeve member 40 and the heating cylinder 12 can also be used as a lubricant.

[0036] In addition, in this embodiment, the band heater 122 is arranged on the outer circumferential surface of the heating cylinder 12, but this is not limiting. The band heater 122 may also be arranged on the outer circumferential surface of the sleeve member 40 to efficiently heat the molten resin.

[0037] In summary, the injection molding machine 10 according to this embodiment only needs to have the following configuration, and can take on a variety of different embodiments. That is, the injection molding machine 10 is an injection molding machine characterized in that it comprises a heating cylinder 12 having a long hole 125 into which molten resin output from the output port 32 of a connecting pipe 30, which is a pipe having a fixed position of the output port 32, can be input, and which heats the molten resin input from the long hole 125, and a sleeve member 40 which is a tubular member fixed to the output port 32 of the connecting pipe 30 and inside which the heating cylinder 12 is arranged so that it can move in the center line direction, and which has a through hole 41 through which the molten resin output from the output port 32 passes toward the long hole 125 of the heating cylinder 12, as long as the heating cylinder 12 moves within a predetermined distance in the center line direction.

[0038] As a result, the heating cylinder 12 of the injection device 11 constituting the injection molding machine 10 has an elongated hole 125 into which the molten resin output from the output port 32 of the connecting pipe 30, whose position is fixed, can be input, and the molten resin input from the elongated hole 125 is heated. In addition, a tubular sleeve member 40 is fixed to the output port 32 of the connecting pipe 30, and has the heating cylinder 12 disposed inside so as to be movable in the centerline direction. The tubular sleeve member 40 has a through-hole 41 through which the molten resin output from the output port 32 passes toward the elongated hole 125 of the heating cylinder 12. As long as the heating cylinder 12 moves within a predetermined distance in the centerline direction, the output port 32 of the connecting pipe 30 and the elongated hole 125 of the heating cylinder 12 face each other. As a result, the injection device 11 of the injection molding machine 10 can be moved away from the mold 50 while the connecting pipe 30, which directly inputs the molten resin output from the output device 20 into the injection molding machine, is fixed. For example, by moving the entire injection unit 11 away from the mold 50, the injection unit 11 can be purged.

[0039] Here, the length of the elongated hole 125 of the heating cylinder 12 in the center line direction may be longer than a predetermined distance. As a result, for example, when the "predetermined distance" is a distance shorter than the length in the center line direction of the long hole 125 of the heating cylinder 12, the following effect is achieved: That is, the molten resin that has passed through the through hole 41 of the sleeve member 40 passes through the long hole 125 of the heating cylinder 12 regardless of the position in the center line direction of the heating cylinder 12 moving inside the sleeve member 40.

[0040] The elongated hole 125 of the heating cylinder 12 may be covered with a sleeve member 40. This makes the elongated hole 125 invisible from the outside, thereby suppressing leakage of the molten resin output from the output port 32 of the connecting pipe 30. Furthermore, entry of foreign matter into the elongated hole 125 of the heating cylinder 12 is suppressed.

[0041] Also, a seal member 42 for sealing the gap between the sleeve member 40 and the heating cylinder 12 may be disposed inside both ends of the sleeve member 40 . This prevents the molten resin from leaking out through the gap between the sleeve member 40 and the heating cylinder 12. Furthermore, it also prevents foreign matter from entering from the outside. Furthermore, it also prevents air from entering from the outside, so that the molten resin inside the sleeve member 40 is prevented from coming into contact with air. As a result, deterioration of the molten resin is suppressed.

[0042] Furthermore, the injection molding system 1 according to this embodiment only needs to have the following configuration, and can take on a variety of different embodiments. That is, the injection molding system 1 is an injection molding system characterized by including: a heating cylinder 12 having a long hole 125 into which molten resin output from the output port 32 of a connecting pipe 30, which is a pipe with a fixed position of the output port 32, can be input, and which heats the molten resin input from the long hole 125; a sleeve member 40 which is a tubular member fixed to the output port 32 of the connecting pipe 30 and has the heating cylinder 12 arranged inside so that it can move in the center line direction, and which has a through hole 41 through which the molten resin output from the output port 32 passes toward the long hole 125 of the heating cylinder 12; an injection molding machine 10 in which the output port 32 of the connecting pipe 30 and the long hole 125 of the heating cylinder 12 face each other as long as the heating cylinder 12 moves within a predetermined distance in the center line direction; an output device 20 which outputs the molten resin; and a connecting pipe 30 which connects the output device 20 to the injection molding machine 10 and through which the molten resin output from the output device 20 flows toward the injection molding machine 10. [Explanation of symbols]

[0043] REFERENCE SIGNS LIST 1... injection molding system, 10... injection molding machine, 11... injection device, 12... heating cylinder, 13... injection cylinder, 20... output device, 30... connecting pipe, 40... sleeve member, 41... sealing member, 50... mold, 51... sprue, 52... inlet

Claims

1. a heating cylinder having a long hole into which the molten resin output from the output port of a pipe having a fixed position can be input, the heating cylinder heating the molten resin input from the long hole; a sleeve member that is a tubular member fixed to the output port of the piping, with the heating cylinder disposed therein so as to be movable in a centerline direction, the sleeve member having a through hole that allows the molten resin output from the output port to pass toward the long hole of the heating cylinder; Equipped with an injection molding machine, characterized in that the output port of the pipe and the long hole of the heating cylinder face each other as long as the heating cylinder moves within a predetermined distance in the center line direction.

2. The length of the elongated hole of the heating cylinder in the center line direction is longer than the predetermined distance.

2. The injection molding machine according to claim 1.

3. The long hole of the heating cylinder is covered by the sleeve member.

2. The injection molding machine according to claim 1.

4. A seal member is disposed inside both ends of the sleeve member to seal a gap between the sleeve member and the heating cylinder.

2. The injection molding machine according to claim 1.

5. a heating cylinder having a long hole into which the molten resin output from the output port of a pipe having a fixed position can be input, the heating cylinder heating the molten resin input from the long hole; a sleeve member that is a tubular member fixed to the output port of the piping, with the heating cylinder disposed therein so as to be movable in a centerline direction, the sleeve member having a through hole that allows the molten resin output from the output port to pass toward the long hole of the heating cylinder; Equipped with an injection molding machine in which the output port of the pipe and the elongated hole of the heating cylinder face each other as long as the heating cylinder moves within a predetermined distance range in a center line direction; an output device that outputs the molten resin; a connecting pipe that connects the output device and the injection molding machine and through which the molten resin output from the output device flows toward the injection molding machine; 1. An injection molding system comprising:

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