Connecting device and molten resin supply system

Abstract

The purpose of the present invention is to suppress the introduction of solid inclusions into an injection molding machine, said solid inclusions being mixed into a molten resin passing through a pipe or being generated in the pipe, together with the molten resin. A connection device (10) constituting a molten resin supply system (1) is provided with a pipe including at least a pipe through which molten resin passes, and is connected to an output device (80) for outputting the molten resin to be recovered by connecting an upstream end of the pipe to the output device (80). The downstream end of the pipe is connected with an injection molding machine (90) for injection molding of the molten resin, so that the output device (80) and the injection molding machine (90) are connected, and the downstream side of the pipe is provided with a removing and melting part (50) for removing or melting solid inclusions mixed in the molten resin.

Description

Technical Field

[0001] This application claims priority based on Japanese Patent Application No. 2023-176626 filed on October 12, 2023. The entire contents of the Japanese Patent Application are incorporated herein by reference.

[0002] The invention relates to a connecting device and a molten resin supply system. Background Art

[0003] In order to directly input the molten resin output from the decontamination machine into the injection molding machine, the decontamination machine is sometimes connected to the injection molding machine through piping, and the decontamination machine uses a mechanical recovery method to remove contaminants contained in the resin to be recovered. At this time, in order to adapt to the movement of the position of the heating cylinder of the injection molding machine when the molten resin in the heating cylinder is discharged (purged), a sleeve (sliding telescopic pipe joint) is sometimes provided on the joint of the piping (for example, Patent Document 1).

[0004] Patent Document 1: International Publication No. 2022 / 056618

[0005] If a sleeve is provided as a joint of the piping, the sleeve will slide in accordance with the movement of the position of the heating cylinder, thereby moving back and forth between the inside and outside of the piping. At this time, the molten resin passing through the inside of the piping may be exposed to the outside of the piping in a state of being attached to the surface of the sleeve. Therefore, when the sleeve slides, the exposed molten resin may be carbonized by friction with it and mixed into the molten resin passing through the piping as a solid inclusion. In the case where solid inclusions are mixed into the molten resin passing through the piping for some reason, including the case where a sleeve is provided as a piping joint, it may cause poor molding quality in an injection molding machine that uses the molten resin as a material for molding. Summary of the invention

[0006] An object of the present invention is to suppress solid inclusions mixed into molten resin passing through a pipe or generated in the pipe from being fed into an injection molding machine together with the molten resin.

[0007] The connecting device of the present invention completed based on the above-mentioned purpose is characterized in that it has a piping including at least a tube for passing molten resin, and the output device and the injection molding machine are connected by connecting the end on the upstream side of the piping to the output device of the molten resin to be recovered, and connecting the end on the downstream side of the piping to the injection molding machine for performing injection molding of the molten resin, and a removal and melting section for removing or melting solid inclusions mixed in the molten resin is provided on the downstream side of the piping.

[0008] Here, a joint may be further provided for displacing a part of the pipe to absorb the movement when at least a part of the injection molding machine moves relative to the output device.

[0009] Furthermore, the melt removal portion may be disposed on the pipe on the downstream side of the joint and on the upstream side of the injection molding machine.

[0010] Furthermore, the removal and melting unit may be a filtering device for removing the solid inclusions by filtering and separating.

[0011] Furthermore, the filtering device may be a screen changer capable of loading, unloading and replacing a filter screen for filtering and separating the solid inclusions.

[0012] Furthermore, the joint may be a sleeve-type telescopic pipe joint.

[0013] Furthermore, the joint may also be a flexible metal hose.

[0014] Furthermore, the joint may also be a rotary joint.

[0015] Furthermore, the present invention is a molten resin supply system, characterized in that it comprises: an output device having an output port at a fixed position and outputting the molten resin to be recovered from the output port; an injection molding machine having an input port that can be moved and using the molten resin input to the input port to mold a molded product; and a connecting device having a pipe for passing the molten resin, the output device and the injection molding machine are connected by connecting the end of the upstream side of the pipe to the output port and the end of the downstream side of the pipe to the input port, and a removal and melting section is provided on the downstream side of the pipe for removing or melting solid inclusions mixed in the molten resin.

[0016] Effects of the Invention

[0017] According to the present invention, it is possible to suppress solid inclusions mixed in the molten resin passing through the pipe or generated in the pipe from being fed into the injection molding machine together with the molten resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a conceptual diagram showing the overall structure of a molten resin supply system including the connecting device according to the first embodiment.

[0019] Figure 2 This is a diagram showing an example of the external appearance structure of a screen changer constituting a coupling device without a melting portion.

[0020] Figure 3The present invention is a diagram showing an example of the structure of a molten resin supply system including a connection device using a sleeve-type expansion joint. (A) is a diagram showing an example of the external structure of the connection device. (B) is an enlarged view of a part of the sleeve-type expansion joint of the connection device.

[0021] Figure 4 The present invention is a diagram showing an example of the structure of a molten resin supply system including a connection device using a flexible metal hose. (A) is a diagram showing an example of the external structure of the connection device. (B) is an enlarged view of a part of the flexible metal hose of the connection device.

[0022] Figure 5 This is a diagram showing an example of the configuration of a molten resin supply system including a coupling device using a rotary joint.

[0023] Figure 6 It is a cross-sectional view of the rotary joint of the connecting device.

[0024] In the figure: 1, 2, 3-molten resin supply system, 10, 20, 30-connecting device, 11, 12, 21, 22, 31, 32, 33, 34-tube, 13-sleeve outer cylinder, 14, 15, 24, 25, 26, 27, 38, 39-connecting component, 23-flexible metal hose, 16, 354-sealing component, 35, 36, 37-rotary joint, 50-melting removal part, 51-main body, 52-connecting part, 53-sliding part, 54-cylinder body, 80-output device, 81-output port, 90-injection molding machine, 91-input port, 111-sleeve, 231, 355-gap, 351-rotor, 352-stator, 353-ball, 533, 534-filter. DETAILED DESCRIPTION

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0026] <First embodiment>

[0027] (Structure of Molten Resin Supply System 1)

[0028] Figure 1 It is a conceptual diagram showing the overall structure of the molten resin supply system 1 including the coupling device 10 according to the first embodiment.

[0029] Figure 2 This is a diagram showing an example of the external appearance structure of a screen changer constituting the coupling device 10 excluding the melting portion 50 .

[0030] Figure 1The molten resin supply system 1 shown includes a connection device 10 , a discharge device 80 that discharges the molten resin to be recovered, and an injection molding machine 90 that performs injection molding using the molten resin.

[0031] [Connection device 10]

[0032] The connecting device 10 is a device having a piping including a tube for passing molten resin, and connecting the output device 80 arranged on the upstream side in the direction connecting the output device 80 and the injection molding machine 90 (hereinafter referred to as the "connection direction") with the injection molding machine 90 arranged on the downstream side through the piping.

[0033] The connecting device 10 has a removal and melting section 50 on the downstream side of the piping for removing or melting solid inclusions mixed into the molten resin. The removal and melting section 50 is arranged on the downstream side of the joint in the piping and the upstream side of the injection molding machine 90, and is arranged at a position where the flow direction of the molten resin does not change. The structure of the piping joint will be described later. In addition, in the removal and melting section 50, the method of removing or melting solid inclusions is not particularly limited. For example, the removal and melting section 50 can be a filtering device that removes solid inclusions by filtering and separation. And, for example, the removal and melting section 50 can be a device that melts solid inclusions by using chemicals, or can be a device that melts solid inclusions by mechanically crushing them. In addition, in the present embodiment, a screen changer is used as a filtering device that removes solid inclusions by filtering and separation.

[0034] A screen changer is a filtering device having a mechanism for cleaning or replacing a filtering and separating portion (hereinafter referred to as a "filter screen"). For example, a screen changer has a plurality of filter screens. The screen changer moves a plurality of filter screens, disposing a portion of the filter screens in a position where solid inclusions can be filtered and separated, and disposing the remaining filter screens in a position where they can be cleaned or replaced. Furthermore, the screen changer has a plurality of paths with filter screens, and in a portion of the paths, solid inclusions are filtered and separated by flowing molten resin, while in the remaining paths, the filter screens can be cleaned or replaced without flowing molten resin.

[0035] like Figure 2 As shown, the screen changer as the melting removal unit 50 is configured to include a main body 51 , a connecting portion 52 , a sliding portion 53 and a cylinder 54 .

[0036] The main body 51 is a component for positioning the connecting part 52, the sliding part 53 and the cylinder part 54. The connecting part 52 is a quadrangular column-shaped component with a through hole. Figure 2 The near side ( Figure 1 downstream side) of the surface 523 and Figure 2 The far side ( Figure 1A through hole 522 is formed on the surface 524 of the upstream side of the connecting portion 52. A plurality of threaded holes 521 are provided on the surface 523 and the surface 524 of the connecting portion 52, respectively, and are connected to the end of the pipe by bolts (not shown) in a manner that allows for detachable and replaceable connection.

[0037] The sliding part 53 is a component that slides in a direction perpendicular to the connection direction. Figure 2 The two through holes 531 and 532 penetrate from the proximal side to the distal side (from the upstream side to the downstream side in the connection direction). The through holes 531 and 532 change their positions in the direction orthogonal to the connection direction as the sliding portion 53 slides. One of the through holes 531 and 532 overlaps with the through hole 522 of the connecting portion 52 by sliding, thereby forming one through hole.

[0038] Filters 533 and 534 having a filtering function of filtering and separating solid inclusions mixed into the molten resin are respectively arranged in the through holes 531 and 532. Figure 1 As shown, the molten resin flowing from the upstream side of the pipe of the connecting device 10 in the direction of the arrow passes through the through hole 522 of the removal melting portion 50 and is filtered by the filter 533 (or filter 534) to separate solid inclusions, and then flows to the downstream side of the pipe.

[0039] Back to Figure 2 The cylinder 54 slides the sliding part 53 in a direction perpendicular to the connection direction by hydraulic pressure or the like, so that the through holes 531 and 532 of the sliding part 53 overlap with the through hole 522 of the connecting part 52. Thus, either of the through holes 531 and 532 arranged at a position overlapping with the through hole 522 of the connecting part 52 filters and separates solid inclusions mixed in the molten resin passing through the inside. Figure 2 FIG. 5 shows a state where the through hole 531 of the sliding portion 53 overlaps with the through hole 522 of the connecting portion 52. At this time, since the through hole 532 of the sliding portion 53 does not overlap with the through hole 522 of the connecting portion 52, Figure 2 As shown, the through hole 532 of the sliding part 53 is arranged at a position away from the pipe. In this state, the filter 534 can be cleaned to remove the blockage or replace the filter 534. In addition, Figure 2 The structure of the screen changer shown as removing the melting portion 50 is an example and is not limited to Figure 2 The structure shown in the figure may also be a screen changer of other structures capable of removing or melting solid inclusions in the molten resin flowing through the pipe.

[0040] [Output device 80]

[0041] return Figure 1The output device 80 is a device for decontaminating the contaminants contained in the resin such as the plastic bottle to be recycled by mechanical recycling (physical recycling method) or chemical recycling (chemical recycling method) method and outputting it as molten resin. The output device 80 has an output port 81 for outputting the decontaminated resin as molten resin. The position of the output port 81 is fixed and connected to the connection device 10. The molten resin decontaminated by the output device 80 is output from the output port 81 and input into the connection device 10.

[0042] "Mechanical recycling" refers to a series of processes in which the contaminants remaining in the resin melted by exposure to high temperature are diffused into the vacuum in the output device 80 and decontaminated by sorting, crushing, and washing the recycled used plastic bottles and other resins to remove dirt and foreign matter on the surface. In addition, "chemical recycling" refers to a series of processes in which the recycled used plastic bottles and other resins are sorted, chemically decomposed, and repolymerized to remove contaminants.

[0043] 〔Injection molding machine 90〕

[0044] The injection molding machine 90 is a molding machine used when manufacturing a molded product using molten resin as a material. The injection molding machine 90 has an input port 91 for inputting molten resin into the machine, and is connected to the output device 80 through the connection device 10. Therefore, the injection molding machine 90 receives the supply of molten resin output from the output device 80, thereby being able to manufacture a molded product using the molten resin as a material. In addition, the injection molding machine 90 can measure the molten resin as a material of the molded product.

[0045] The injection molding machine 90 is set at a fixed position as a whole, but a part of the injection molding machine 90 may move. For example, when the heating cylinder (not shown) discharges (clears) the molten resin, the position of the input port 91 of the molten resin as the material may move. As described above, since the position of the output port 81 of the output device 80 is fixed, it is necessary to absorb the movement of the position of the input port 91 of the molten resin. In contrast, in the molten resin supply system 1, the movement of the position of the input port 91 of the injection molding machine 90 is absorbed by the following structure of the connecting device 10.

[0046] Figure 3 1 is a diagram showing an example of the configuration of a molten resin supply system 1 including a coupling device 10 using a telescopic pipe joint. Figure 3 (A) is a diagram showing an example of the external appearance structure of the coupling device 10 . Figure 3 (B) is an enlarged view of a portion of the telescopic pipe joint of the coupling device 10 .

[0047] The coupling device 10 includes pipes 11 and 12 , a sleeve outer tube 13 , and connecting members 14 and 15 , and these are coupled to form a single pipe as a whole.

[0048] The tubes 11 and 12 are metal tubes through which the molten resin passes and which have a circular cross-sectional shape. The tube 11 is a tube whose upstream end is connected to the output device 80 by a connecting member 14 and whose downstream end is connected to the sleeve outer tube 13. The tube 11 has a sleeve 111 which constitutes a sleeve type expansion joint as a joint for piping together with the sleeve outer tube 13 at a part of the downstream side. The tube 12 is a tube whose upstream end is connected to the sleeve outer tube 13 and whose downstream end is connected to the injection molding machine 90 by a connecting member 15.

[0049] The connecting member 14 is a member for connecting the coupling device 10 to the output device 80, and is fixed to the output device 80 by a flange or the like. A sealing member is sandwiched between the connecting member 14 and the tube 11, and they are connected by being fixed with bolts or the like. The connecting member 15 is a member for connecting the coupling device 10 to the injection molding machine 90, and is fixed to the injection molding machine 90 by a flange or the like. A sealing member is sandwiched between the connecting member 15 and the tube 12, and they are connected by being fixed with bolts or the like.

[0050] like Figure 3 (A) is an enlarged view of the dotted line area 100. Figure 3 As shown in (B), the sleeve type expansion joint is configured such that the sleeve 111 of the pipe 11 reciprocates inside the sleeve outer tube 13. The interior of the sleeve outer tube 13 is maintained airtight and watertight by a sealing member 16.

[0051] In the connection device 10, when at least a part of the injection molding machine 90 moves relative to the output device 80, a sleeve type expansion joint is used as a joint that displaces a part of the piping to absorb the movement. Therefore, even if the position of the connection component 15 moves in the connection direction due to the movement of a part of the injection molding machine 90, the movement is absorbed within the range in which the sleeve 111 can reciprocate inside the sleeve outer cylinder 13. Here, "a part of the movement" of the injection molding machine 90 refers to, for example, the movement for discharging (purging) molten resin from the heating cylinder, which is not shown in the figure.

[0052] However, since the sleeve 111 reciprocates inside the sleeve outer cylinder 13, the molten resin passing through the sleeve outer cylinder 13 may be exposed to the outside in a state of being attached to the surface of the sleeve 111. At this time, since the sleeve 111 reciprocates, the molten resin exposed to the outside may be carbonized by friction with it, and these may be mixed into the molten resin as solid inclusions. In addition, the molten resin retained in the internal gap may be degraded by heat or carbonized by friction, which may cause the generation of solid inclusions.

[0053] Therefore, the coupling device 10 has a portion located downstream of the telescopic sleeve joint and upstream of the injection molding machine 90, and at a position where the flow direction of the molten resin does not change. Figure 2 The melted portion 50 is removed. Specifically, Figure 3 As shown in FIG. 1A , a screen changer serving as a melt removal section 50 is connected to a region 101 indicated by a dotted line of the tube 12. Thus, the molten resin flowing from the upstream side of the tube 12 is filtered and separated from solid inclusions by the screen changer, and then flows to the downstream side of the tube 12. As a result, the molten resin from which the solid inclusions have been removed is input into the injection molding machine 90.

[0054] As described above, the coupling device according to the first embodiment of the present invention only needs to adopt the following structure, and various embodiments can be adopted.

[0055] That is, the connection device 10 involved in the first embodiment is characterized in that it has a piping including at least tubes 11 and 12 for passing molten resin, and the output device 80 and the injection molding machine 90 are connected by connecting the end on the upstream side of the piping to the output device 80 for outputting the molten resin to be recovered, and connecting the end on the downstream side of the piping to the injection molding machine 90 for performing injection molding of the molten resin, and a removal and melting section 50 is provided on the downstream side of the piping to remove or melt solid inclusions mixed in the molten resin.

[0056] Thus, by connecting the upstream end of the pipe through which the molten resin passes to the output device 80 for outputting the molten resin, and connecting the downstream end of the pipe to the injection molding machine 90 for performing injection molding of the molten resin, the connection device 10 connecting the output device 80 and the injection molding machine 90 has a removal and melting section 50 for removing or melting solid inclusions mixed in the molten resin on the downstream side of the pipe. As a result, it is possible to suppress the solid inclusions mixed in the molten resin passing through the pipe from being input into the injection molding machine 90 together with the molten resin, thereby suppressing the quality of the molded product molded by the injection molding machine 90 from being deteriorated. In addition, when the molten resin as a material is measured in the injection molding machine 90, the molten resin is measured with the mixing of solid inclusions suppressed, so the accuracy of the measurement result can be improved.

[0057] Here, a joint may be provided for displacing a part of the pipe to absorb the movement when at least a part of the injection molding machine 90 moves relative to the output device 80 .

[0058] This can prevent solid inclusions generated inside or outside the joint that has displaced a portion of the pipe from being fed into the injection molding machine 90 together with the molten resin.

[0059] Furthermore, the melt removal portion 50 may be disposed on the downstream side of the joint that displaces a portion of the pipe to absorb the movement thereof and on the upstream side of the injection molding machine 90 .

[0060] Thus, solid inclusions generated inside or outside the joint that displaces a portion of the piping are removed or melted by the removal and melting section 50 arranged on the downstream side of the joint and upstream side of the injection molding machine 90, thereby preventing them from being input into the injection molding machine 90 together with the molten resin.

[0061] Furthermore, the removal and melting unit 50 may be a filtering device for removing solid inclusions by filtering and separating.

[0062] Thus, the solid inclusions mixed in the molten resin passing through the pipe are filtered and separated by the filtering device as the melting removal unit 50 disposed on the downstream side of the pipe and removed, thereby preventing the solid inclusions from being input into the injection molding machine 90 together with the molten resin.

[0063] Furthermore, the filtering device for removing the melted portion 50 may be a screen changer capable of loading and unloading and replacing a filter screen for filtering and separating solid inclusions.

[0064] Thus, solid inclusions mixed in the molten resin passing through the pipe are separated and removed by filtering by the screen changer as a filtering device arranged on the downstream side of the pipe, thereby preventing the solid inclusions from being input into the injection molding machine 90 together with the molten resin.

[0065] Furthermore, the joint for displacing a portion of the pipe may be a telescopic pipe joint of a sleeve type.

[0066] Thus, solid inclusions mixed in the molten resin passing through the pipe including the telescopic pipe joint are removed or melted by the removal and melting unit 50 disposed on the downstream side of the pipe, thereby preventing the solid inclusions from being input into the injection molding machine 90 together with the molten resin.

[0067] <Second embodiment>

[0068] (Structure of Molten Resin Supply System 2)

[0069] Figure 41 is a diagram showing an example of the structure of a molten resin supply system 2 including a coupling device 20 using a flexible metal hose 23 . Figure 4 (A) is a diagram showing an example of the external appearance structure of the coupling device 20 . Figure 4 (B) is an enlarged view of a portion of the flexible metal hose 23 of the connection device 20 .

[0070] Figure 4 The molten resin supply system 2 shown is configured to include: a connection device 20; a delivery device 80 that delivers the molten resin to be recovered; and an injection molding machine 90 that performs injection molding using the molten resin.

[0071] [Connection device 20]

[0072] The connection device 20 is a device that has a pipe including a tube through which molten resin passes, and connects the output device 80 arranged on the upstream side in the connection direction and the injection molding machine 90 arranged on the downstream side through the pipe. The connection device 20 is configured to include pipes 21 and 22, a flexible metal hose 23 having connection members 24 and 25, and connection members 26 and 27, and these are connected to form a single pipe as a whole.

[0073] The tubes 21 and 22 are metal tubes through which the molten resin passes and which have a circular cross-sectional shape. The tube 21 is a tube whose upstream end is connected to the output device 80 through the connecting member 26 and whose downstream end is connected to the connecting member 24 of the flexible metal hose 23. The tube 22 is a tube whose upstream end is connected to the connecting member 25 of the flexible metal hose 23 and whose downstream end is connected to the injection molding machine 90 through the connecting member 27.

[0074] The flexible metal hose 23 is a hose that can be bent in a direction perpendicular to the connection direction, and functions as a joint for piping. Figure 4 (A) is an enlarged view of the dotted line area 200. Figure 4 As shown in (B), the flexible metal hose 23 has a plurality of corrugated gaps 231 formed inside.

[0075] The connecting member 26 is a member for connecting the coupling device 20 to the output device 80, and is fixed to the output device 80 by a flange or the like. A sealing member is sandwiched between the connecting member 26 and the tube 21, and they are connected by being fixed with bolts or the like. The connecting member 27 is a member for connecting the coupling device 20 to the injection molding machine 90, and is fixed to the injection molding machine 90 by a flange or the like. A sealing member is sandwiched between the connecting member 27 and the tube 22, and they are connected by being fixed with bolts or the like.

[0076] In the connection device 20, when at least a part of the injection molding machine 90 moves relative to the output device 80, a flexible metal hose 23 is used as a joint that displaces a part of the pipe to absorb the movement. Therefore, even if the position of the connection member 27 moves in a direction orthogonal to the connection direction as a part of the injection molding machine 90 moves, the movement is absorbed within the range in which the flexible metal hose 23 can be bent. However, as described above, since the flexible metal hose 23 has a plurality of corrugated gaps 231 formed inside, there is a possibility that a part of the molten resin passing through the inside of the flexible metal hose 23 enters the gaps 231 and is retained, thereby solidifying and being mixed into the molten resin as a solid inclusion.

[0077] Therefore, the coupling device 20 has a position on the downstream side of the flexible metal hose 23 and the upstream side of the injection molding machine 90, and at a position where the flow direction of the molten resin does not change. Figure 2 The melted portion 50 is removed. Specifically, Figure 4 As shown in FIG. 2A , a screen changer serving as a melt removal section 50 is connected to a region 201 indicated by a dotted line of the tube 22. Thus, the molten resin flowing from the upstream side of the tube 22 is filtered and separated from solid inclusions by the screen changer, and then flows to the downstream side of the tube 22. As a result, the molten resin from which the solid inclusions have been removed is input into the injection molding machine 90.

[0078] The configurations of the output device 80 and the injection molding machine 90 constituting the molten resin supply system 2 are the same as those of the output device 80 and the injection molding machine 90 constituting the molten resin supply system 1 according to the first embodiment described above, and thus description thereof is omitted.

[0079] As described above, the coupling device according to the second embodiment of the present invention only needs to adopt the following structure, and various embodiments can be adopted.

[0080] That is, the connection device 20 involved in the second embodiment is characterized in that it has a piping including at least tubes 21 and 22 for passing molten resin, and the output device 80 and the injection molding machine 90 are connected by connecting the end on the upstream side of the piping to the output device 80 for outputting the molten resin to be recovered, and connecting the end on the downstream side of the piping to the injection molding machine 90 for performing injection molding of the molten resin, and a removal and melting section 50 is provided on the downstream side of the piping to remove or melt solid inclusions mixed in the molten resin.

[0081] Thus, by connecting the upstream end of the pipe through which the molten resin passes to the output device 80 that outputs the molten resin, and connecting the downstream end of the pipe to the injection molding machine 90 that performs injection molding of the molten resin, the connection device 20 that connects the output device 80 and the injection molding machine 90 has a removal and melting portion 50 that removes or melts solid inclusions mixed in the molten resin on the downstream side of the pipe. Thus, it is possible to prevent solid inclusions mixed in the molten resin passing through the pipe from being input into the injection molding machine 90 together with the molten resin.

[0082] Here, the joint for displacing a part of the pipe may be the flexible metal hose 23 .

[0083] Thus, solid inclusions mixed in the molten resin passing through the pipe including the flexible metal hose 23 are removed or melted by the removal and melting unit 50 disposed on the downstream side of the pipe, thereby preventing the solid inclusions from being input into the injection molding machine 90 together with the molten resin.

[0084] <Third embodiment>

[0085] (Structure of Molten Resin Supply System 3)

[0086] Figure 5 1 is a diagram showing an example of the configuration of a molten resin supply system 3 including a coupling device 30 using a rotary joint. Figure 6 It is a cross-sectional view of the rotary joint 35 of the coupling device 30 .

[0087] Figure 5 The molten resin supply system 3 shown is configured to include: a connection device 30; a delivery device 80 that delivers the molten resin to be recovered; and an injection molding machine 90 that performs injection molding using the molten resin.

[0088] [Connection device 30]

[0089] The connection device 30 is a device that has a pipe including a tube through which molten resin passes, and connects the output device 80 arranged on the upstream side in the connection direction and the injection molding machine 90 arranged on the downstream side through the pipe. The connection device 30 is configured to include pipes 31 to 34, rotary joints 35 to 37, and connecting members 38 and 39, and forms a meandering shape of the pipe that meanders in the up-down direction by connecting these.

[0090] The tubes 31 to 34 are metal tubes through which the molten resin passes and have a circular cross-sectional shape. The tube 31 is a tube whose upstream end is connected to the output device 80 through the connecting member 38, and whose downstream end is connected to the rotary joint 35. The tube 32 is a tube whose upstream end is connected to the rotary joint 35, and whose downstream end is connected to the rotary joint 36. The tube 33 is a tube whose upstream end is connected to the rotary joint 36, and whose downstream end is connected to the rotary joint 37. The tube 34 is a tube whose upstream end is connected to the rotary joint 37, and whose downstream end is connected to the injection molding machine 90 through the connecting member 39.

[0091] The rotary joint 35 is a rotary joint as a pipe joint that connects the lower end in the up-down direction to the pipe 31 and the upper end to the pipe 32. The rotary joint is a joint that connects a plurality of pipes together rotatably. The rotary joint 35 can rotate the pipes 31 and 32 via the rotating shaft 401. A sealing member (not shown) is sandwiched between the rotary joint 35 and the pipes 31 and 32, and they are connected by fixing with bolts or the like.

[0092] like Figure 5 The enlarged view of the dotted area 300 is Figure 6 As shown in FIG. 4 , the rotary joint 35 is composed of a so-called "rolling bearing" having a rotor 351, a stator 352, and a ball 353. The rotary joint 35 can rotate the rotor 351 and the stator 352 separately through the rotating shaft 401. In addition, the rotary joint 35 has a sealing member 354 for preventing leakage of the molten resin passing through the inside. A small gap 355 is formed between the rotor 351 and the stator 352 inside the rotary joint 35, but the sealing member 354 can prevent leakage of the molten resin.

[0093] return Figure 5 The rotary joint 36 is a rotary joint that connects the lower end in the up-down direction to the tube 32 and the upper end to the tube 33. The rotary joint 36 can rotate the tubes 32 and 33 via the rotating shaft 402. In addition, according to the change in the position of the rotary joint 37 in the connection direction described later, the rotary joint 36 changes the position in the circumferential direction of the rotating shaft 401 of the rotary joint 35 and the circumferential direction of the rotating shaft 403 of the rotating joint 37 that changes its position. In addition, the internal structure of the rotary joint 36 is the same as the internal structure of the rotary joint 35.

[0094] The rotary joint 37 is a rotary joint that connects the upper end in the vertical direction to the tube 33 and the lower end to the tube 34. The rotary joint 37 can rotate the tubes 33 and 34 via the rotating shaft 403. If the position of the connecting member 39 changes in the connection direction as a part of the injection molding machine 90 moves, the rotary joint 37 changes position accordingly. The internal structure of the rotary joint 37 is the same as the internal structure of each of the rotary joints 35 and 36.

[0095] The connecting member 38 is a member for connecting the coupling device 30 to the output device 80, and is fixed to the output device 80 by a flange or the like. A sealing member is sandwiched between the connecting member 38 and the tube 31, and they are connected by being fixed with bolts or the like. The connecting member 39 is a member for connecting the coupling device 30 to the injection molding machine 90, and is fixed to the injection molding machine 90 by a flange or the like. A sealing member is sandwiched between the connecting member 39 and the tube 34, and they are connected by being fixed with bolts or the like.

[0096] In the connection device 30, when at least a part of the injection molding machine 90 moves relative to the output device 80, a rotary joint is used as a joint that displaces a part of the pipe to absorb the movement. Therefore, even if the position of the connection member 39 moves in the connection direction as a part of the injection molding machine 90 moves, the movement is absorbed within the range in which the rotary joints 35 to 37 can rotate. However, for example, as described above, Figure 6 As shown, the rotary joint 35 has a small gap 355 formed between the rotor 351 and the stator 352. Therefore, there is a possibility that a part of the molten resin passing through the interior of the rotary joint 35 enters the gap 355 and is retained, thereby solidifying and being mixed into the molten resin as a solid inclusion. The same is true for the rotary joints 36 and 37.

[0097] Therefore, the coupling device 30 has a position on the downstream side of the rotary joint 37 and the upstream side of the injection molding machine 90, and at a position where the flow direction of the molten resin does not change. Figure 2 The melted portion 50 is removed. Specifically, Figure 5 As shown in FIG. 1 , a screen changer serving as the melt removal section 50 is connected to the region 301 indicated by the dotted line of the tube 34. Thus, the molten resin flowing from the upper side of the tube 34 is filtered and separated from solid inclusions by the screen changer, and then flows to the lower side of the tube 34. As a result, the molten resin from which the solid inclusions have been removed is input into the injection molding machine 90.

[0098] The configurations of the output device 80 and the injection molding machine 90 constituting the molten resin supply system 3 are the same as those of the output device 80 and the injection molding machine 90 constituting the molten resin supply system 1 according to the first embodiment described above, and thus description thereof is omitted.

[0099] In summary, the coupling device according to the third embodiment of the present invention only needs to adopt the following structure, and various embodiments can be adopted.

[0100] That is, the connection device 30 involved in the third embodiment is characterized in that it has a piping including at least tubes 31 to 34 for passing molten resin, and the output device 80 and the injection molding machine 90 are connected by connecting the end on the upstream side of the piping to the output device 80 for outputting the molten resin to be recovered, and connecting the end on the downstream side of the piping to the injection molding machine 90 for performing injection molding of the molten resin, and a removal and melting section 50 is provided on the downstream side of the piping to remove or melt solid inclusions mixed in the molten resin.

[0101] Thus, by connecting the upstream end of the pipe through which the molten resin passes to the output device 80 that outputs the molten resin, and connecting the downstream end of the pipe to the injection molding machine 90 that performs injection molding of the molten resin, the connection device 30 that connects the output device 80 and the injection molding machine 90 has a removal and melting portion 50 that removes or melts solid inclusions mixed in the molten resin on the downstream side of the pipe. Thus, it is possible to prevent solid inclusions mixed in the molten resin passing through the pipe from being input into the injection molding machine 90 together with the molten resin.

[0102] Here, the joints for displacing a part of the pipe may be the rotary joints 35 to 37 .

[0103] Thus, solid inclusions mixed into the molten resin passing through the pipe including the rotary joint are removed or melted by the removal and melting unit 50 disposed on the downstream side of the pipe, thereby preventing the solid inclusions from being fed into the injection molding machine 90 together with the molten resin.

[0104] <Comparison of implementation methods>

[0105] When comparing the connection device 10 according to the first embodiment, the connection device 20 according to the second embodiment, and the connection device 30 according to the third embodiment, they all have in common that they have a screen changer as a melting removal portion 50 at a position where the flow direction of the molten resin does not change, downstream of a joint (e.g., a sleeve-type expansion joint, a flexible metal hose, a rotary joint) that displaces a portion of the pipe and upstream of the injection molding machine 90. This makes it possible to remove solid inclusions mixed in the molten resin flowing through each pipe of the connection devices 10, 20, and 30. However, the amount of solid inclusions mixed in the molten resin or the frequency of solid inclusions mixed in the molten resin differs.

[0106] That is, since the connection device 10 according to the first embodiment is a connection device using a sleeve-type expansion joint, as described above, the molten resin exposed to the outside of the pipe may rub against it and carbonize, and there is a possibility that these may be mixed into the molten resin as solid inclusions. Figure 3 The longer the reciprocating sliding distance of (A) and (B)) and the larger the area of ​​the portion exposed to the outside, the easier it is for solid inclusions to form.

[0107] Furthermore, the connection device 20 according to the second embodiment is a connection device using a flexible metal hose. Therefore, as described above, since a plurality of corrugated gaps 231 are formed inside, there is a possibility that a portion of the molten resin passing through the inside of the flexible metal hose 23 may enter the gaps 231 and stagnate, thereby solidifying and being mixed into the molten resin as a solid inclusion (see Figure 4 (A) and (B)). In the connection device 20 according to the second embodiment, the longer the length of the flexible metal hose 23 is and the greater the number of the corrugated gaps 231 formed inside, the more solid inclusions are likely to be formed.

[0108] Furthermore, the connection device 30 according to the third embodiment is a connection device using a rotary joint as a joint, and therefore, as described above, a small gap 355 is formed between the rotor 351 and the stator 352. Therefore, there is a possibility that a part of the molten resin passing through the inside of the rotary joint 35 enters the gap 355 and is retained, thereby solidifying and being mixed into the molten resin as a solid inclusion (see Figure 6 ).

[0109] However, the gap 355 in which the molten resin may be retained is narrower in the rotary joint of the connection device 30 according to the third embodiment. Therefore, the connection device 30 according to the third embodiment reduces the amount of solid inclusions mixed into the molten resin or the frequency of solid inclusions mixed into the molten resin compared to the connection device 10 according to the first embodiment or the connection device 20 according to the second embodiment. As a result, the frequency of cleaning the screen changer as the removal melting part 50 or the frequency of replacing the screen changer is reduced.

Claims

1. A connecting device, characterized in that: having a piping including at least a pipe through which molten resin passes, The upstream end of the pipe is connected to a discharging device for discharging the molten resin to be recovered, and the downstream end of the pipe is connected to an injection molding machine for performing injection molding of the molten resin, thereby connecting the discharging device and the injection molding machine. A removal and melting portion for removing or melting solid inclusions mixed in the molten resin is provided on the downstream side of the pipe.

2. The connection device according to claim 1, characterized in that: A joint is further provided for displacing a part of the pipe to absorb the movement when at least a part of the injection molding machine moves relative to the output device.

3. The connection device according to claim 2, characterized in that: The melt removal section is disposed on the pipe on the downstream side of the joint and on the upstream side of the injection molding machine.

4. The connection device according to claim 1, characterized in that: The removal and melting part is a filtering device for removing the solid inclusions by filtering and separating.

5. The connection device according to claim 4, characterized in that: The filtering device is a screen changer capable of loading, unloading and replacing a filter screen for filtering and separating the solid inclusions.

6. The connection device according to claim 2 or 3, characterized in that: The joint is a sleeve type telescopic pipe joint.

7. The connection device according to claim 2 or 3, characterized in that: The joint is a flexible metal hose.

8. The connection device according to claim 2 or 3, characterized in that: The joint is a rotary joint.

9. A molten resin supply system, characterized in that: have: An output device has an output port at a fixed position and outputs the molten resin to be recovered from the output port; An injection molding machine having an input port that can be moved to a position, and using the molten resin input to the input port to mold a molded product; and A connecting device includes a pipe through which the molten resin passes, wherein the output device and the injection molding machine are connected by connecting the upstream end of the pipe to the output port and the downstream end of the pipe to the input port, and a removal and melting portion is provided on the downstream side of the pipe for removing or melting solid inclusions mixed in the molten resin.

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