Connecting device and molten resin supply system

Abstract

A molten resin supply system (1) is provided with a coupling device (10) for coupling together a cleaner (80) for outputting a molten resin to be recovered from an output port (801) and an injection molding machine (90) comprising: a heating cylinder (91) having an input port (911) for inputting the output molten resin, the heating cylinder (91) having an output port (911) through which the output molten resin is input; heating the molten resin; and an injection cylinder which is independent of the heating cylinder (91) and injects the heated molten resin into the mold, one end of a pipe formed by pipes (11-14) for passing the molten resin and rotary joints (21-23) is connected to the output port (801) through a connecting part (31), and the other end of the pipe is connected to the input port (911) through a connecting part (32), so that the cleaner (80) and the injection molding machine (90) are connected together.

Description

Technical Field

[0001] This invention relates to a connecting device and a molten resin supply system. Background Technology

[0002] In order to allow molten resin from a decontamination machine, which removes contaminants from the resin of the target material using mechanical recycling methods, to be directly fed into an injection molding machine, the decontamination machine and the injection molding machine are sometimes connected together by piping. In this case, in order to accommodate the positional movement of the heating cylinder caused by the discharge (removal) of molten resin from the heating cylinder of the injection molding machine, a sleeve (sliding telescopic pipe joint) is sometimes provided on the pipe joint (for example, Patent Document 1).

[0003] Existing technical documents Patent documents Patent Document 1: International Publication No. 2022 / 056618 Summary of the Invention

[0004] The technical problem to be solved by the invention If a sleeve is used as a connector for the piping, the sleeve will slide in accordance with the positional movement of the heating cylinder, thus 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 sometimes be exposed to the outside of the piping in a state of adhering to the surface of the sleeve. Therefore, when the sleeve slides, the exposed molten resin may sometimes be rubbed and carbonized, or the carbonized resin may sometimes mix into the molten resin passing through the inside of the piping, causing the molten resin to deteriorate.

[0005] The object of the present invention is to suppress leakage of molten resin through the pipe from the joint, compared to the case where a sleeve is provided as a connector for a pipe that connects the device for discharging molten resin and the injection molding machine.

[0006] means for solving technical problems The present invention, completed with respect to the stated purpose, is a connecting device that connects an output device and an injection molding machine. The output device outputs molten resin of a recyclable object from an output port. The injection molding machine has: a heating cylinder having an input port for inputting the output molten resin and heating the molten resin; and an injection cylinder, independent of the heating cylinder, for injecting the heated molten resin into a mold. One end of a pipe formed by a tube through which the molten resin passes and a rotary joint is connected to the output port, and the other end is connected to the input port, thereby connecting the output device and the injection molding machine together.

[0007] Here, the number of rotary joints provided in the connecting device can be three.

[0008] Furthermore, the rotary joint may have a sealing component with a preset heat resistance temperature and durability pressure.

[0009] Furthermore, the connecting device can heat the molten resin passing through the piping by heating the piping.

[0010] Furthermore, the connecting device can heat the piping using a belt heater.

[0011] Furthermore, the rotary joint can be rotated via a sliding bearing, and a portion of the molten resin is used as a lubricant for the sliding bearing.

[0012] Furthermore, it can be characterized in that the rotation axis of the rotary joint is not parallel to the vertical direction, but is approximately perpendicular to the direction of movement of the heating cylinder.

[0013] Furthermore, it can be characterized in that the imaginary straight line connecting one end and the other end of the piping is approximately parallel to the direction of movement of the heating cylinder.

[0014] Furthermore, it can be characterized in that the imaginary straight line connecting one end and the other end of the piping is approximately orthogonal to the rotation axis of the rotary joint.

[0015] Furthermore, the feature is that the length of the first piping section including the rotary joint closest to the said end and the length of the third piping section including the rotary joint furthest from the said end are each less than 30% of the length of the second piping section including the rotary joint disposed between the first piping section and the third piping section.

[0016] Furthermore, the present invention is a molten resin supply system, characterized in that it comprises the output device, the injection molding machine and the connecting device, wherein the position of the output port of the output device is fixed, and the position of the input port of the heating cylinder moves according to the position of the heating cylinder.

[0017] Furthermore, the present invention is a molten resin supply system, characterized in that it comprises the output device, the injection molding machine, and the connecting device, such that even if the output device and the injection molding machine move relative to each other, the imaginary straight line connecting the rotation axes of the three rotary joints connected by the two pipes will not be a straight line when viewed from the top and bottom, or, processing is performed to ensure that it will not be a straight line when viewed from the top and bottom.

[0018] Furthermore, the output device or the injection molding machine can control the reduction of the internal pressure based on the magnitude of the internal pressure of the rotary joint.

[0019] Furthermore, as a control, the output device or the injection molding machine can control the pressure when the molten resin is output from the output port.

[0020] Furthermore, as said control, the output device or the injection molding machine can control at least one of the output of the molten resin from the output device and the input of the molten resin to the injection molding machine.

[0021] Furthermore, the output device can calculate the magnitude of the internal pressure based on information detected at the inlet and outlet of the molten resin in the rotary joint.

[0022] Furthermore, the output port of the output device and the input port of the injection molding machine can each be located on approximately the same horizontal straight line in the vertical direction.

[0023] Invention Effects According to the present invention, compared with the case where a sleeve is provided as a connector for a pipe that connects the device for discharging molten resin and the injection molding machine, leakage of molten resin through the pipe from the connector can be suppressed. Attached Figure Description

[0024] Figure 1 This is a front view showing a portion of the external structure of the molten resin supply system including the connecting device according to the first embodiment.

[0025] Figure 2 This is a schematic diagram of the structure of an injection molding machine that constitutes the molten resin supply system.

[0026] Figure 3 It is a diagram showing the changing positional relationships of the rotary joint.

[0027] Figure 4 This is a front view showing a portion of the external structure of the molten resin supply system including the connecting device according to the second embodiment.

[0028] Figure 5 This is a front view showing a portion of the external structure of the molten resin supply system including the connecting device according to the third embodiment.

[0029] Figure 6 This is a front view showing a portion of the external structure of the molten resin supply system including the connecting device according to the fourth embodiment.

[0030] Figure 7 This is a front view showing a portion of the external structure of the molten resin supply system according to the fifth embodiment.

[0031] Figure 8This is a plan view showing a portion of the external structure of the molten resin supply system according to the fifth embodiment.

[0032] Figure 9 This is a plan view showing a portion of the external structure of the molten resin supply system according to the sixth embodiment.

[0033] Figure 10 (A) and (B) are both front views showing a portion of the external structure of the molten resin supply system according to the seventh embodiment. Detailed Implementation

[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0035] <First Embodiment> (Structure of the molten resin supply system) Figure 1 This is a front view showing a portion of the external structure of the molten resin supply system 1, including the connecting device 10 according to the first embodiment.

[0036] Figure 2 This is a schematic structural diagram of the injection molding machine 90 that constitutes the molten resin supply system 1.

[0037] Figure 1 The molten resin supply system 1 shown is configured as a system including a connecting device 10, a decontaminator 80 as an example of an output device for molten resin, and an injection molding machine 90. The connecting device 10 is a device consisting of piping that connects the decontaminator 80, which is located on the first side in the direction connecting the decontaminator 80 and the injection molding machine 90 (hereinafter referred to as the "connection direction"), to the injection molding machine 90, which is located on the second side. Furthermore, the term "connection direction" does not indicate a strict positional relationship between the decontaminator 80 and the injection molding machine 90 connected by the connecting device 10. Hereinafter, as a description of the same direction as the connection direction, it is sometimes referred to as the direction of movement of the heating cylinder 91 of the injection molding machine 90. The connecting device 10 is configured as a piping system including pipes 11 to 14, rotary joints 21 to 23, and connecting parts 31 and 32, which are connected to form a zigzag shape in the vertical direction.

[0038] Pipes 11 to 14 are metal pipes with a circular cross-sectional shape for passing through molten resin. Pipe 11 is a pipe with one end connected to the connecting member 31 and the other end connected to the rotary joint 21. Pipe 11 has a curved shape that allows molten resin flowing from the first side to the second side in the connection direction to flow upwards in the vertical direction. Pipe 12 is a pipe with one end connected to the rotary joint 21 and the other end connected to the rotary joint 22. Pipe 12 has a zigzag shape that allows molten resin flowing from the lower side in the vertical direction to flow sequentially towards the second side in the connection direction, the lower side in the vertical direction, the second side in the connection direction, and the upper side in the vertical direction.

[0039] Pipe 13 is a pipe connected at one end to rotary joint 22 and at the other end to rotary joint 23. Pipe 13 has a curved shape that allows molten resin flowing from the lower side to the upper side in the vertical direction to flow sequentially to the second side in the connecting direction and then to the lower side in the vertical direction. Pipe 14 is a pipe connected at one end to rotary joint 23 and at the other end to connecting member 32. Pipe 14 has a straight shape that allows molten resin flowing from the upper side to the lower side in the vertical direction to flow directly to the lower side.

[0040] Rotary joint 21 is a joint in which the lower end is connected to pipe 11 and the upper end is connected to pipe 12. Rotary joint 21 allows pipes 11 and 12 to rotate via rotating shaft 401. Here, a rotary joint refers to a joint that allows multiple pipes to be rotatably connected. Although not shown, the rotary joint includes: a shaft and bearings, capable of rotating the central axis of the connected pipes as a rotation axis; a sealing member to prevent leakage of internal fluid (molten resin in this embodiment); and a grease-sealing part, which seals in grease as a lubricant to maintain smooth rotation of the shaft. Additionally, a grease nipple may be provided as a grease replenishment port. The rotary joint and the pipes are connected together by clamping a rubber O-ring as a sealing member and securing it with bolts or the like.

[0041] The bearings of the rotary joint are composed of so-called "rolling bearings" that rotate the shaft via steel balls and bearings, and so-called "sliding bearings" that directly contact the shaft and receive its rotation through a surface. In this embodiment, the bearings of the rotary joints 21 to 23 are rolling bearings. However, in this embodiment, the bearings can be changed between rolling bearings and sliding bearings depending on the internal heat resistance temperature and durability pressure of the rotary joints 21 to 23.

[0042] The sealing components of the rotary joint have preset heat resistance temperature and durability pressure. The heat resistance temperature and durability pressure of the sealing components are determined by the physical properties of the resin to be recycled, the pressure within the connecting device 10 (e.g., the amount of molten resin), etc. For example, when the resin to be recycled is polyethylene terephthalate (PET resin), it is preferable to have a temperature and pressure that can withstand the molten state of the PET resin.

[0043] Specifically, for example, regarding the heat resistance temperature, it is set to 300 degrees Celsius, which is higher than the melting point temperature of homopolymer PET resin and has a slight margin. Regarding the durability pressure, it is preferably set to 25 MPa (megapascals), which is a pressure with a margin that is expected to be required based on various conditions, including the amount of resin input from the output port 801 of the decontamination machine 80 to the connecting device 10 and output from the connecting device 10 to the input port 911 of the injection molding machine 90.

[0044] When there is a trade-off between the heat resistance temperature and durability pressure of the sealing component, the heat resistance temperature of the sealing component increases when the internal pressure of the rotary joint is reduced, thus suppressing the deterioration of the sealing component. Furthermore, the method for reducing the internal pressure of each of the rotary joints 21 to 23 involved in this embodiment will be described later. Also, when the resin of the recycling target is changed, the heat resistance temperature is determined to be the melting point of that resin + α.

[0045] Rotary joint 22 is a rotary joint whose lower end is connected to pipe 12 and its upper end is connected to pipe 13 in the vertical direction. Rotary joint 22 allows pipes 12 and 13 to rotate via rotating shaft 402. Furthermore, the position of rotary joint 22 changes in the circumferential direction of rotating shaft 401 of rotary joint 21 and in the circumferential direction of rotating shaft 403 of rotary joint 23, which causes the position change, depending on the positional change of the connection direction of rotary joint 22 (described later). For further information on the positional change of rotary joint 22, please refer to... Figure 3 The details will be provided later.

[0046] Rotary joint 23 is a joint whose upper end is connected to pipe 13 and whose lower end is connected to pipe 14 in the vertical direction. Rotary joint 23 allows pipes 13 and 14 to rotate via rotating shaft 403. Furthermore, when the position of the heating cylinder 91 of the injection molding machine 90 moves, the position of rotary joint 23 changes accordingly. For example, the position of the heating cylinder 91 moves when molten resin is discharged (removed), but the entire injection molding machine 90 does not move. For further information on the position change of rotary joint 23, please refer to... Figure 3 The details will be provided later.

[0047] In addition, such as Figure 1As shown, the connecting device 10 according to the first embodiment forms four paths extending in the vertical direction. Therefore, each path can be equipped with four swivel joints, but the total number of swivel joints is three (swivel joints 21 to 23). That is, for one of the four paths extending in the vertical direction (the path formed by pipe 12), although a swivel joint could be configured, it is intentionally not configured. This is because, although there is no limit to the number of swivel joints that can be configured, if the number of swivel joints increases, the pipe track becomes correspondingly unstable, and various costs also increase. Therefore, considering the stability of the pipe track and the cost, the number of swivel joints configured is preferably three.

[0048] The connecting component 31 is used to connect the connecting device 10 to the decontamination machine 80 (described later), and is fixed to the decontamination machine 80 by a flange or the like. Specifically, the end of the connecting component 31 on the first side of the connecting direction is connected to the output port 801 of the decontamination machine 80, and the end on the second side of the connecting direction is connected to the pipe 11. The connecting component 31 and the pipe 11 are connected together by clamping a rubber O-ring, which serves as a sealing component, and fixing it with bolts or the like.

[0049] The connecting component 32 is used to connect the connecting device 10 to the injection molding machine 90 (described later), and is fixed to the injection molding machine 90 by a flange or the like. Specifically, the upper end of the connecting component 32 in the vertical direction is connected to the pipe 14, and the lower end in the vertical direction is connected to the inlet 911 of the heating cylinder 91 provided in the injection molding machine 90. The connecting component 32 and the pipe 14 are connected together by clamping a rubber O-ring as a sealing component and fixing it with bolts or the like.

[0050] Furthermore, when the connecting device 10 is a structure capable of controlling a gear pump (not shown) disposed in the cleaning machine 80, the connecting device 10 can reduce the internal pressure of the connecting device 10 and reduce the internal pressure of the rotary joints 21 to 23 by reducing the amount of molten resin output from the output port 801 of the cleaning machine 80.

[0051] The decontamination machine 80 is a device that removes contaminants contained within the resin of recycled polyester bottles and other materials using mechanical recycling (physical regeneration) and chemical recycling (chemical regeneration) methods, and outputs the molten resin as a final product. "Mechanical recycling" refers to a series of processes: removing surface dirt and impurities by screening, crushing, and washing the recycled used polyester bottles and other resin; then, removing residual contaminants from the resin, which has melted under high temperatures, by diffusing it into a vacuum within the decontamination machine 80. "Chemical recycling" refers to a series of processes involving screening, chemically decomposing, and repolymerizing the recycled used polyester bottles and other resin to remove contaminants.

[0052] As described above, the decontamination machine 80 has an output port 801 for outputting the decontaminated resin as molten resin. A connecting member 31 of the connecting device 10 is connected to the output port 801, and the molten resin decontaminated by the decontamination machine 80 is input into the connecting device 10 from the connecting member 31 connected to the output port 801.

[0053] Here, in order to suppress thermal stress generated in the connecting device 10, the vertical position of the output port 801 of the cleaning machine 80 is fixed on a horizontal straight line that is approximately the same as the vertical position of the input port 911 of the injection molding machine 90. Furthermore, regarding the relationship between the vertical position of the output port 801 of the cleaning machine 80 and the vertical position of the input port 911 of the injection molding machine 90, it is compared with a reference... Figure 4 The comparison of the second embodiment will be described later.

[0054] The cleaning machine 80 controls the reduction of the internal pressure of each of the rotary joints 21 to 23 of the connecting device 10 based on the magnitude of their respective internal pressures. For example, the cleaning machine 80 can control the output of molten resin to the connecting device 10 based on information detected in the connecting parts 31 and 32, which respectively correspond to the inlet and outlet of the connecting device 10, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Here, the information detected in the connecting parts 31 and 32 includes, for example, information related to the flow rate of the molten resin per unit time (input and output flow rates, etc.) detected by a flow sensor (not shown), information related to the temperature of the molten resin, and information related to the pressure of the molten resin. The pressure of the molten resin can also be determined based on the amount of molten resin inside the connecting device 10, which is determined based on the amount of molten resin input and output in the connecting device 10.

[0055] Specifically, for example, if the information detected in connecting parts 31 and 32 indicates an anomaly (abnormal pressure, temperature, etc.), the cleaning machine 80 can control the flow to stop the output of molten resin to the connecting device 10 and reduce the internal pressure of each of the rotary joints 21 to 23. Furthermore, for example, if the information detected in connecting parts 31 and 32 does not indicate an anomaly, but shows a tendency to become abnormal if it remains unchanged despite a low degree of urgency, the cleaning machine 80 can control the output of molten resin to the connecting device 10, reduce the internal pressure of the connecting device 10, and reduce the internal pressure of each of the rotary joints 21 to 23.

[0056] Furthermore, for example, the cleaning machine 80 can control the output of molten resin to the connecting device 10 based on information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23, thereby reducing the internal pressure of each of the rotary joints 21 to 23. Here, the information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23 may be, for example, information related to the flow rate of the molten resin per unit time detected by a flow sensor (not shown). By performing the control described above, for example, when there is a trade-off between the heat resistance temperature and durability pressure of the sealing components (not shown) of the rotary joints 21 to 23, the durability pressure of the sealing components can be reduced to increase the heat resistance temperature.

[0057] Specifically, as a control of the output of molten resin to the connecting device 10, the cleaning machine 80, for example, controls the pressure when molten resin is output from the output port 801. At this time, although not shown, the cleaning machine 80 reduces the pressure when molten resin is output from the output port 801 by controlling the gear pump used for outputting molten resin and the amount of resin output from the output port 801.

[0058] Furthermore, the decontamination unit 80 can control the output (flow rate and pressure) of molten resin based on the amount of molten resin used in the injection molding machine 90 and the amount of molten resin discharged from the injection molding machine 90. In situations where the decontamination unit 80 is sometimes running continuously and it is difficult to control the output of molten resin to reduce its volume, a buffer unit for temporarily storing excess molten resin or an alternative path for the excess molten resin to flow can be provided. Additionally, if there is excessive excess molten resin, it can be directed towards a waste disposal path or connected to the input port of another injection molding machine for supply.

[0059] Furthermore, when the cleaning machine 80 is able to control the production volume of molded products (e.g., products, preforms of products) of the injection molding machine 90, the output (flow rate and pressure) of molten resin from the output port 801 can be controlled by increasing the production volume of molded products of the injection molding machine 90.

[0060] Injection molding machine 90 is a molding machine used to manufacture molded articles using molten resin as a material. Injection molding machine 90 is connected to decontamination machine 80 via connecting device 10, thus enabling it to receive molten resin supplied from decontamination machine 80 and manufacture molded articles using that molten resin as a material. For example... Figure 2As shown, the injection molding machine 90 is configured to include a heating cylinder 91, an injection cylinder 92, and a mold 93. The injection molding machine 90 is a so-called pre-plasticizing plunger type (also known as a pre-plasticizing type) injection molding machine, which combines the separate heating cylinder 91 and injection cylinder 92. Therefore, the axis in the longitudinal direction of the heating cylinder 91 and the axis in the longitudinal direction (i.e., the connecting direction) of the injection cylinder 92 are not on the same axis.

[0061] Heating cylinder 91 is a cylinder body that heats the molten resin, which is the material for the molded article, and feeds the required amount of molten resin into injection cylinder 92. Heating cylinder 91 is configured to include an inlet 911 for inputting molten resin, a screw 912 for heating the input molten resin, and an outlet 913 for outputting the heated molten resin. Heating cylinder 91 heats the molten resin using shear heat generated by rotating the screw 912 and heat from a belt heater (not shown), and outputs the molten resin to injection cylinder 92 from outlet 913. The belt heater is, for example, a lightweight and thin cylindrical heater, whose nickel-chromium wire is insulated by a heat-resistant mica sheet and whose outer shell is covered by a stainless steel sheet. The inner surface of the belt heater in contact with the piping is relatively smooth, allowing for easy contact with the cylindrical piping through simple operations.

[0062] The injection cylinder 92 is a cylinder for injecting molten resin into the interior of the mold 93. The injection cylinder 92 is configured to include: an inlet 921 for inputting molten resin output from the outlet 913 of the heating cylinder 91; a plunger 922 for pressurizing the input molten resin towards a second side in the connecting direction; and an injection port 923 for injecting the pressurized molten resin into the interior of the mold 93. The mold 93 shapes the molten resin through mold opening and closing operations and cools it to solidify it, thus completing a molded article (e.g., a product, a preform of a product).

[0063] The injection molding machine 90 controls the reduction of the internal pressure of each of the rotary joints 21 to 23 of the connecting device 10 based on the magnitude of their respective internal pressures. For example, the injection molding machine 90 can control the input of molten resin output from the connecting device 10 based on information detected in the connecting member 31 and connecting member 32 of the connecting device 10, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Here, the information detected in the connecting member 31 and connecting member 32 may include, for example, information related to the flow rate of the molten resin per unit time (input and output flow rates, etc.) detected by a flow sensor (not shown), information related to the temperature of the molten resin, and information related to the pressure of the molten resin. The pressure of the molten resin can also be determined based on the amount of molten resin inside the connecting device 10, which is determined based on the input and output amounts of the molten resin in the connecting device 10.

[0064] Specifically, for example, when the information detected in connecting parts 31 and 32 indicates an anomaly (pressure anomaly, temperature anomaly, etc.), the injection molding machine 90 can control itself to reduce the internal pressure of the connecting device 10 and the internal pressure of the rotary joints 21 to 23 by increasing the flow rate from the connecting device 10 to the machine. Furthermore, for example, when the information detected in connecting parts 31 and 32 does not indicate an anomaly, but shows a tendency to become an anomaly if it remains unchanged despite low urgency, the injection molding machine 90 can reduce the internal pressure of the connecting device 10 and the internal pressure of the rotary joints 21 to 23 by increasing the flow rate from the connecting device 10 to the machine.

[0065] Furthermore, for example, the injection molding machine 90 can control the input of molten resin from the connecting device 10 based on information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Here, the information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23 may be, for example, information related to the flow rate of the molten resin per unit time detected by a flow sensor (not shown).

[0066] As a control of the input of molten resin output from the connecting device 10, the injection molding machine 90, for example, controls the flow rate of molten resin input to the input port 911. At this time, the injection molding machine 90, for example, controls the operation of the screw 912 and plunger 922, which are located downstream of the input port 911 and used in the transport of molten resin, thereby creating a free space downstream to allow molten resin to escape. This increases the flow rate of molten resin input to the input port 911, thus reducing the internal pressure of the connecting device 10 and the internal pressure of the rotary joints 21 to 23.

[0067] Furthermore, when the injection molding machine 90 is configured to control the gear pump (not shown) disposed in the decontamination machine 80, the injection molding machine 90 can reduce the internal pressure of the connecting device 10 and the internal pressure of the rotary joints 21 to 23 by reducing the amount of molten resin output from the output port 801 of the decontamination machine 80.

[0068] (Positioning of the rotary joint) Figure 3 This is a diagram showing the changing positional relationship between rotary joints 21 and 23.

[0069] exist Figure 3 The image shows the view from the top to the bottom in a vertical direction. Figure 2 The diagram shows the changing positional relationships of rotary joints 21 to 23. The solid lines representing the positional relationships of rotary joints 21 to 23 indicate the position of injection molding machine 90 (reference). Figure 2 Examples of positional relationships during normal operation. In contrast, the positional relationship between the rotary joint 21 (shown as a solid line) and the rotary joints 22 and 23 (shown as dashed lines) illustrates an example of the positional relationship when the heating cylinder 91 of the injection molding machine 90 moves. Furthermore, as described above, the output port 801 of the cleaning machine 80 (reference...) Figure 1 Given that the position of the rotary joint 21 is fixed, the position of the rotary joint 21 is also fixed.

[0070] like Figure 3 As shown, the positional relationship of rotary joints 21 to 23 when the injection molding machine 90 is operating normally is as follows: the rotation axis 402 of the rotary joint 22 (shown by the solid line) is positioned at a position offset to the rear side in the forward and backward direction from the imaginary straight line 700 connecting the rotation axis 401 of the rotary joint 21 and the rotation axis 403 of the rotary joint 23 (shown by the solid line).

[0071] At this point, the position of the rotary joint 23, shown by the solid line, is the second side closest to the connection direction within the movable range. However, even in this position, the rotation axis 402 of the rotary joint 22 is not positioned on the imaginary straight line 700. Specifically, the connecting device 10 is configured such that the combined length of the imaginary straight line 701 connecting the rotation axis 401 of the rotary joint 21 and the rotation axis 402 of the rotary joint 22, and the length of the imaginary straight line 702 connecting the rotation axis 402 of the rotary joint 22 and the rotation axis 403 of the rotary joint 23, is longer than the length of the imaginary straight line 700.

[0072] The length of the hypothetical straight line 700 is determined by factors such as the installation position of the injection molding machine 90 and the range of movement of the heating cylinder 91. Furthermore, the length of the hypothetical straight line 701 is determined by the length of the tube 12 (reference). Figure 1 The shape and length of the imaginary straight line 702 are determined by taking the shape and length of the tube 13 (reference) as conditions. Figure 1 The shape, length, etc. of the imaginary straight line 701 are determined as conditions. When designing the connecting device 10, the above conditions can be taken into account so that the sum of the lengths of the imaginary straight line 701 and the imaginary straight line 702 is longer than the length of the imaginary straight line 700.

[0073] That is, when the position of the heating cylinder 91 of the injection molding machine 90 moves, the connecting device 10 correspondingly repeats the action of extending in the connecting direction (the action of being pulled towards the second side) and the action of retracting in the connecting direction (the action of being pushed towards the first side). When these actions are viewed from the upper side to the lower side in the vertical direction, for example, as Figure 3As shown, the rotating shaft 402 of the rotary joint 22 rotates clockwise during the extension of the connecting device 10 along the connecting direction, and rotates counterclockwise during the retraction of the connecting device 10 along the connecting direction.

[0074] Here, it is assumed that the connecting device 10 is a structure that forms a straight line in the connecting direction (imagine lines 701 and 702 forming a straight line when viewed from above). In this case, if the rotating shaft 403 of the rotary joint 23 is to move to the first side, either a force causing the rotating shaft 402 of the rotary joint 22 to rotate counterclockwise or clockwise will be applied. As a result, the rotating shaft 402 of the rotary joint 22 becomes unpredictable in whether it rotates counterclockwise or clockwise, thus the piping track is unstable. Alternatively, while forming a structure that makes the imaginary lines 701 and 702 form a straight line when viewed from above, a stop can be provided to prevent the rotating shaft 402 from rotating clockwise. However, this would place a load on the stop, the rotating shaft, the piping, etc. For this reason, the connecting device 10 is preferably structured such that even if the cleaning machine 80 and the injection molding machine 90 move relative to each other, the imaginary straight lines 701 and 702 will not be a straight line when viewed from the top and bottom.

[0075] As such a structure, for example, an upper limit can be set for the amount of movement of the heating cylinder 91, or the part size of the injection molding machine 90 can be determined so that when the position of the rotation axis 403 of the rotary joint 22 moves in the connection direction, the sum of the lengths of the imaginary straight line 701 and the imaginary straight line 702 is always longer than the length of the imaginary straight line 700. Specifically, for example, an upper limit can be set for the movement control, or the part size can be determined so that when the heating cylinder 91 is maximally moved towards the second side in the connection direction, the sum of the lengths of the imaginary straight line 701 and the imaginary straight line 702 is always longer than the length of the imaginary straight line 700.

[0076] Furthermore, for example, a stop component can be provided to prevent the rotation axis 402 of the rotary joint 22 from being positioned on the imaginary straight line 700. Additionally, as a process to prevent the rotation axis 402 of the rotary joint 22 from being positioned on the imaginary straight line 700, the position of the rotation axis 402 of the rotary joint 22 can be detected, and when the rotation axis 402 of the rotary joint 22 approaches the imaginary straight line 700, a warning message, sound, etc., can be output, or the system can be stopped.

[0077] Furthermore, when the rotation axis 402 of the rotary joint 22 is positioned on the imaginary straight line 700, if the rotary joint 23 moves to the first side in the connection direction, it is possible that a force (eccentric load) is applied to move the rotary joint 22 to the first side in the connection direction instead of a force intended to move the rotary joint 22 in the forward / backward direction. Therefore, in order to prevent the rotation axis 402 of the rotary joint 22 from being positioned on the imaginary straight line 700, the relationship between the length of the imaginary straight line 700, the length of the imaginary straight line 701, and the length of the imaginary straight line 702 is considered.

[0078] When the heating cylinder 91 of the injection molding machine 90 (reference) Figure 1 and Figure 2 When the position of the connecting component 32 moves to the first side in the connection direction, the connecting component 32 (reference) Figure 1 The rotary joint 23 moves along with it to the first side in the connection direction. Specifically, as... Figure 3 As shown, the solid line indicates that the rotary joint 23 moves along the direction of the arrow to the position indicated by the dashed line. In this way, the rotary joint 22 moves counterclockwise in the circumferential direction of the rotary joint 21. Specifically, as... Figure 3 As shown, the rotary joint 22, indicated by the solid line, moves in the direction of the arrow to the position indicated by the dashed line.

[0079] Therefore, imaginary line 701 moves to the position of imaginary line 703, and imaginary line 702 moves to the position of imaginary line 704. Additionally, Figure 3 The large circle of the dashed line shown indicates the circumferential direction of the rotary joint 21, but does not indicate the movable range of the rotary joint 22. The movable range of the rotary joint 22 is determined by the movable range of the rotary joint 23, the distance between the rotary joint 21 and the rotary joint 22, and the distance between the rotary joint 22 and the rotary joint 23.

[0080] In summary, the connecting device according to the first embodiment of the present invention can be implemented in various ways as long as it adopts the following structure.

[0081] That is, the connecting device 10 according to the first embodiment is a connecting device that connects a cleaning machine 80 and an injection molding machine 90 together. The cleaning machine 80 outputs molten resin of the object to be recovered from the output port. The injection molding machine 90 has: a heating cylinder 91 with an input port 911 for inputting the output molten resin and heating the hot melt resin; and an injection cylinder 92, independent of the heating cylinder 91, for injecting the heated molten resin into the mold 93. One end of the piping formed by the pipes 11 to 14 through which the molten resin passes and the rotary joints 21 to 23 is connected to the output port 801 by means of a connecting member 31, and the other end is connected to the input port 911 by means of a connecting member 32, thereby connecting the cleaning machine 80 and the injection molding machine 90 together.

[0082] Thus, one end of the piping formed by the pipes 11 to 14 through which the molten resin passes and the rotary joints 21 to 23 is connected to the output port 801 of the cleaning machine 80 via the connecting member 31, and the other end of the piping is connected to the input port 911 of the injection molding machine 90 via the connecting member 32, thereby connecting the cleaning machine 80 and the injection molding machine 90 together. In this way, when rotary joints 21 to 23 are used as joints for the pipes through which the molten resin passes, unlike when a sleeve is used as a joint, the sleeve will not slide back and forth between the inside and outside of the piping, thus preventing the molten resin passing through the piping from leaking out of the joint.

[0083] Here, the number of rotary joints provided in the connecting device 10 can be 3.

[0084] Therefore, since the connecting device 10 has three rotary joints (e.g., rotary joints 21 to 23) serving as pipe fittings, the pipe track can be flexibly changed as the position of the heating cylinder 91 relative to the injection molding machine 90 moves, compared to cases where the number of rotary joints is one or two. Furthermore, compared to cases where the number of rotary joints is four or more, the pipe track can be stabilized, and various costs (procurement cost, maintenance cost, debugging cost, etc. of rotary joints) can be suppressed.

[0085] Furthermore, rotary joints 21 to 23 may have sealing components with preset heat resistance temperature and durability pressure.

[0086] Therefore, the sealing components of rotary joints 21 to 23 have preset heat resistance temperature and durability pressure. The heat resistance temperature and durability pressure of the sealing components are determined based on the physical properties of the resin to be recycled, the pressure within the connecting device 10 (e.g., the amount of molten resin), etc. For example, the temperature and pressure at which the resin to be recycled can be transported in a molten state are determined as the heat resistance temperature and durability pressure. In cases where there is a trade-off between the heat resistance temperature and durability pressure of the sealing components, the heat resistance temperature of the sealing components increases when the internal pressure of the rotary joint is reduced. As a result, the deterioration of the sealing components of each of the rotary joints 21 to 23 can be suppressed.

[0087] Furthermore, the connecting device 10 can heat the molten resin passing through the piping formed by the pipes 11 to 14 through which the molten resin passes and the rotary joints 21 to 23.

[0088] Therefore, the connecting device 10 heats the molten resin passing through the piping by heating the piping. The heating temperature is preferably a temperature matching the temperature of the resin being recycled inside the piping, and more preferably a temperature higher than the melting point of the resin being recycled inside the piping but lower than the heat resistance temperature of the sealing components of the rotary joints 21 to 23. Furthermore, the heating of the piping includes overheating to maintain the temperature of the piping within a predetermined range. As a result, the molten resin output from the decontamination machine 80 can be prevented from cooling and solidifying before being input into the injection molding machine 90. Moreover, since the molten resin is input into the heating cylinder 91 at a high temperature, energy savings are achieved when the heating cylinder 91 is heating.

[0089] Furthermore, the connecting device 10 can heat the piping via a belt heater.

[0090] Belt heaters are lightweight and thin cylindrical heaters with smooth inner surfaces that come into contact with piping, allowing for easy and close mounting to cylindrical piping. This results in highly efficient heating of the piping.

[0091] Furthermore, the rotary joints 21 to 23 can enable the tubes 12 and 13 to rotate via sliding bearings, and a portion of the molten resin is used as a lubricant for the sliding bearings.

[0092] Therefore, when the tube can be rotated via the sliding bearings of the rotary joints 21 to 23, a portion of the molten resin passing through the rotary joints 21 to 23 is used as a lubricant. As a result, no additional lubricant needs to be prepared, and it is possible to prevent additional lubricant from mixing into the molten resin.

[0093] Furthermore, the molten resin supply system according to the first embodiment of the present invention can be implemented in various ways as long as it adopts the following structure.

[0094] That is, the molten resin supply system 1 according to the first embodiment is a molten resin supply system characterized in that it includes a decontamination machine 80, an injection molding machine 90 and a connecting device 10, the position of the output port 801 of the decontamination machine 80 is fixed, and the position of the input port 911 of the heating cylinder 91 moves according to the position of the heating cylinder 91.

[0095] Therefore, even if the position of the output port 801 of the cleaning machine 80 is fixed and the position of the input port 911 of the heating cylinder 91 moves, the path of the piping can be flexibly changed by means of the rotary joints 21 to 23, which serve as connectors. As a result, compared to the case where a sleeve is used as a connector for the piping connecting the cleaning machine and the injection molding machine, leakage of molten resin through the piping from the connector can be suppressed.

[0096] Furthermore, the molten resin supply system 1 is a molten resin supply system characterized by comprising a cleaning machine 80, an injection molding machine 90, and a connecting device 10, such that even if the cleaning machine 80 and the injection molding machine 90 move relative to each other, the imaginary straight lines 701 and 702 of the rotation axes 401 to 403 of the three rotary joint points 21 to 23 connected by the two pipes 12 and 13 of the connecting device 10 will not be a straight line when viewed from the vertical direction, or, a process is performed to ensure that the imaginary straight lines 701 and 702 will not be a straight line when viewed from the vertical direction.

[0097] Therefore, the imaginary straight lines 701 and 702 connecting the rotation axes 401 to 403 of the three rotary joints 21 to 23 connected by the two pipes 12 and 13 will not be straight lines when viewed from the top and bottom. As a result, the piping track can be stabilized compared to the case where the imaginary straight lines 701 and 702 connecting the rotation axes 401 to 403 of the three rotary joints 21 to 23 are straight lines when viewed from the top and bottom.

[0098] Here, the cleaning machine 80 or the injection molding machine 90 can control the reduction of the internal pressure of the rotary joints 21 to 23 according to the magnitude of their respective internal pressures.

[0099] For example, as described above, the decontamination machine 80 reduces the output of molten resin to the connecting device 10 based on information detected in the connecting parts 31 and 32, and information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Furthermore, the decontamination machine 80 reduces the output of molten resin to the connecting device 10 based on the amount of molten resin used in the injection molding machine 90 and the amount of molten resin discharged from the injection molding machine 90, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Furthermore, the injection molding machine 90 increases the input of molten resin output from the connecting device 10 based on information detected in the connecting parts 31 and 32, and information detected at the inlet and outlet of the molten resin at each of the rotary joints 21 to 23, thereby reducing the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23. Therefore, when there is a trade-off between the heat resistance temperature and the durability pressure of the sealing components (not shown) of the rotary joints 21 to 23, the durability pressure of the sealing components can be reduced to increase the heat resistance temperature, thereby suppressing the deterioration of the sealing components.

[0100] Furthermore, as a control for reducing the internal pressure of each of the rotary joints 21 to 23, the cleaning machine 80 or the injection molding machine 90 can control the pressure when molten resin is discharged from the output port 801 of the cleaning machine 80.

[0101] Therefore, as a control for reducing the internal pressure of rotary joints 21 to 23, the pressure when molten resin is discharged from the output port 801 of the cleaning machine 80 is controlled. As a result, when there is a trade-off between the heat resistance temperature and the durability pressure of the sealing components of rotary joints 21 to 23, the durability pressure of the sealing components can be reduced to increase the heat resistance temperature, thus suppressing the deterioration of the sealing components.

[0102] Furthermore, as a control for reducing the pressure when molten resin is discharged from the output port 801, the cleaning machine 80 or the injection molding machine 90 can control at least one of the output of molten resin from the cleaning machine 80 and the input of molten resin to the injection molding machine 90.

[0103] Therefore, the output of molten resin from the cleaning machine 80 and the input of molten resin to the injection molding machine 90 are controlled. As a result, the internal pressure of the connecting device 10 and the internal pressure of each of the rotary joints 21 to 23 can be reduced. Therefore, for example, when there is a trade-off between the heat resistance temperature and the durability pressure of the sealing components of each of the rotary joints 21 to 23, the durability pressure of the sealing components can be reduced to increase the heat resistance temperature, thereby suppressing the deterioration of the sealing components.

[0104] Furthermore, the cleaning machine 80 or the injection molding machine 90 can also calculate the magnitude of the internal pressure of each of the rotary joints 21 to 23 based on the information detected at the inlet and outlet of the molten resin in each of the rotary joints 21 to 23.

[0105] Therefore, the internal pressure of the rotary joints is calculated based on information related to the molten resin detected at the inlet and outlet of the molten resin in each of the rotary joints 21 to 23. As a result, the internal pressure of each of the rotary joints 21 to 23 can be controlled based on the calculated values.

[0106] Furthermore, the output port 801 of the cleaning machine 80 and the input port 911 of the injection molding machine 90 can each be located on approximately the same horizontal straight line in the vertical direction.

[0107] Therefore, the output port 801 of the cleaning machine 80 and the input port 911 of the injection molding machine 90 are each located on approximately the same horizontal straight line in the vertical direction, thus suppressing thermal stress caused by the thermal expansion of the piping. As a result, compared to the case where the output port of the cleaning machine and the input port of the injection molding machine are not located on approximately the same horizontal straight line in the vertical direction (for example, the connecting device 20 according to the second embodiment described later), piping damage caused by thermal stress can be suppressed. Furthermore, regarding the relationship between the vertical position of the output port 801 of the cleaning machine 80 and the vertical position of the input port 911 of the injection molding machine 90, compared with reference... Figure 4 The comparison of the second embodiment will be described later.

[0108] <Second Implementation> (Structure of the molten resin supply system) Figure 4 This is a front view showing a portion of the external structure of the molten resin supply system 2 according to the second embodiment.

[0109] The structure of the molten resin supply system 2 according to the second embodiment is basically the same as the structure of the molten resin supply system 1 according to the first embodiment. However, as Figure 1 and Figure 4 As shown, the position of the output port 801 of the cleaning machine 80 in the first embodiment in the vertical direction is different from the position of the output port 811 of the cleaning machine 81 in the second embodiment in the vertical direction. Therefore, the shape of the piping of the connecting device 20 in the second embodiment is different from the shape of the piping of the connecting device 10 in the first embodiment.

[0110] The structure of the connecting device 20 according to the second embodiment is as follows. That is, as shown below. Figure 4 As shown, the connecting device 20 is a device formed by a pipe that connects the cleaning machine 81, which is arranged on the first side of the connecting direction, and the injection molding machine 90, which is arranged on the second side. The connecting device 20 is composed of pipes 41 to 44, swivel joints 51 to 53, and connecting parts 61 and 62, and is a tortuous pipe formed by connecting them.

[0111] Pipes 41 to 44 are metal pipes through which molten resin passes. Pipe 41 is a pipe with one end connected to connecting member 61 and the other end connected to rotary joint 51. Pipe 41 has a curved shape that allows molten resin flowing from the first side to the second side in the connection direction to flow downwards in the vertical direction. Pipe 42 is a pipe with one end connected to rotary joint 51 and the other end connected to rotary joint 52. Pipe 42 has a curved shape that allows molten resin flowing from the upper side in the vertical direction to flow sequentially towards the second side in the connection direction and then upwards in the vertical direction.

[0112] Pipe 43 is a pipe connected at one end to rotary joint 52 and at the other end to rotary joint 53. Pipe 43 has a curved shape that allows molten resin flowing from the lower side to the upper side in the vertical direction to flow sequentially to the second side in the connecting direction and then to the lower side in the vertical direction. Pipe 44 is a pipe connected at one end to rotary joint 53 and at the other end to connecting member 62. Pipe 44 has a straight shape that allows molten resin flowing from the upper side to the lower side in the vertical direction to flow directly to the lower side.

[0113] Rotary joint 51 is a rotary joint whose upper end is connected to pipe 41 and whose lower end is connected to pipe 42 in the vertical direction. Rotary joint 51 allows pipes 41 and 42 to rotate via rotating shaft 71. Rotary joint 52 is a rotary joint whose lower end is connected to pipe 42 and whose upper end is connected to pipe 43 in the vertical direction. Rotary joint 52 allows pipes 42 and 43 to rotate via rotating shaft 72. Furthermore, according to the position change of rotary joint 53 in the connection direction described later, rotary joint 52 changes its position in the circumferential direction of rotating shaft 71 of rotary joint 51 and in the circumferential direction of rotating shaft 73 of rotary joint 53, which causes the position change. In addition, the position change of rotary joint 52 is the same as described above. Figure 3 The position of the rotary joint 22 changes in the same way.

[0114] Rotary joint 53 is a joint in which the upper end is connected to pipe 43 and the lower end is connected to pipe 44 in the vertical direction. Rotary joint 53 allows pipes 43 and 44 to rotate via rotating shaft 73. Furthermore, when the position of heating cylinder 91 of injection molding machine 90 moves, the position of rotary joint 53 changes accordingly. The position change of rotary joint 53 is similar to that described above. Figure 3 The position of the rotary joint 23 changes in the same way.

[0115] The connecting component 61 is used to connect the connecting device 20 to the cleaning machine 81, and is fixed to the cleaning machine 81 by a flange or the like. Specifically, the end of the connecting component 61 on the first side of the connecting direction is connected to the output port 811 of the cleaning machine 81, and the end on the second side of the connecting direction is connected to the pipe 41. The connecting component 62 is used to connect the connecting device 20 to the injection molding machine 90, and is fixed to the injection molding machine 90 by a flange or the like. Specifically, the upper end of the connecting component 62 in the vertical direction is connected to the pipe 44, and the lower end in the vertical direction is connected to the input port 911 of the heating cylinder 91 provided in the injection molding machine 90.

[0116] <Comparison between Embodiment 1 and Embodiment 2> The connecting device 20 according to the second embodiment, like the connecting device 10 according to the first embodiment, suppresses leakage of molten resin through the pipe from the joint compared to the case where a sleeve is used as a connector for the pipe connecting the cleaning machine and the injection molding machine. However, if the connecting device 10 of the first embodiment (refer to...) Figure 1 The connecting device 20 of the second embodiment (see reference) Figure 4 Compare them, for example, in the following aspects where they differ.

[0117] That is, such as Figure 1 As shown, the vertical position of the output port 801 of the cleaning machine 80 connected to the connecting device 10 according to the first embodiment is located on a horizontal straight line that is approximately the same as the vertical position of the input port 911 of the injection molding machine 90. In contrast, as... Figure 4 As shown, the position of the output port 811 in the cleaning machine 81 connected to the connecting device 20 according to the second embodiment in the vertical direction is not located on a horizontal straight line that is approximately the same as the position of the input port 911 of the injection molding machine 90 in the vertical direction.

[0118] Due to Figure 1 In the first embodiment shown, the output port 801 of the cleaning machine 80 and the input port 911 of the injection molding machine 90 connected by the connecting device 10 are each located on approximately the same horizontal straight line in the vertical direction. Therefore, even if the piping of the connecting device 10 is overheated by a belt heater or the like and thermal expansion occurs, thermal stress generated in the connecting device 10 can be suppressed. As a result, damage such as breakage of the pipes 11 to 14 constituting the piping and the bearings of the rotary joints 21 to 23 can be suppressed.

[0119] Furthermore, in Figure 1In the connecting device 10 according to the first embodiment shown, the four paths forming the piping extending in the vertical direction are located on the same side (upper side) in the vertical direction relative to the output port 801 and the input port 911. Therefore, the expansion direction of the piping during thermal expansion can be made consistent, thereby further suppressing the generation of thermal stress in the connecting device 10. Specifically, in the first side of the connecting direction of the connecting device 10, thermal expansion occurs in the direction from the lower side to the upper side in the vertical direction, and in the second side of the connecting direction, thermal expansion occurs to the same extent in the direction from the lower side to the upper side in the vertical direction. At this time, the generation of thermal stress in the connecting device 10 can be further suppressed, thereby further suppressing damage such as breakage of the pipes 11 to 14 constituting the piping and the bearings of the rotary joints 21 to 23.

[0120] In contrast, with Figure 4 In the second embodiment shown, the output port 811 of the cleaning machine 81 and the input port 911 of the injection molding machine 90 connected by the connecting device 20 are not on approximately the same horizontal straight line in the vertical direction, thus thermal stress is easily generated in the connecting device 20. Furthermore, in Figure 4 In the connecting device 20 according to the second embodiment shown, the three paths forming the piping extending in the vertical direction are not on the same side in the vertical direction relative to the output port 811 and the input port 911. That is, these three paths are located on the lower side in the vertical direction relative to the output port 811 and on the upper side in the vertical direction relative to the input port 911. Therefore, it is impossible to make the expansion direction of the piping of the connecting device 20 when it is overheated and undergoes thermal expansion consistent. Specifically, in the first side of the connecting direction of the connecting device 20, thermal expansion occurs in the direction from the upper side to the lower side in the vertical direction, and in the second side of the connecting direction, thermal expansion occurs to the same extent in the direction from the lower side to the upper side in the vertical direction.

[0121] At this time, thermal stress is generated in the connecting device 20, causing damage such as breakage to the pipes 41 to 44 constituting the piping, the shafts of the rotary joints 51 to 53, bearings, and sealing components, and the molten resin flowing inside may leak out. Therefore, compared with the structure of the connecting device 20 according to the second embodiment, the structure of the connecting device 10 according to the first embodiment is preferred, that is, the structure in which the output port 801 of the cleaning machine 80 and the input port 911 of the injection molding machine 90 are respectively located on a horizontal straight line in the vertical direction. Furthermore, compared with the structure in which the expansion direction of the piping is opposite when it is thermally expanded due to overheating, the structure in which the expansion direction of the piping is the same when it is thermally expanded due to overheating is even more preferred. Based on the above, the connecting device 20 involved in the second embodiment can be said to be a structure that can be selected when there are limitations such as the positional relationship between the cleaning machine 81 and the injection molding machine 90, the position of the output port 811 of the cleaning machine 81, and the position of the input port 911 of the injection molding machine 90, and it is not possible to arrange the position of the output port 811 of the cleaning machine 81 in the vertical direction and the position of the input port 911 of the injection molding machine 90 in the vertical direction on approximately the same horizontal straight line.

[0122] And, even in cases like Figure 1 As with the connecting device 10 of the first embodiment shown, if the output port 801 of the cleaning machine 80 and the input port 911 of the injection molding machine 90 are each located on a horizontal straight line in the vertical direction, it is possible that the expansion directions during thermal expansion of the piping when it is overheated are inconsistent. As a third embodiment, this structure will be described below.

[0123] <Third Implementation> (Structure of the molten resin supply system) Figure 5 This is a front view showing a portion of the external structure of the molten resin supply system 3 according to the third embodiment.

[0124] like Figure 4 and Figure 5 As shown, the structure of the molten resin supply system 3 according to the third embodiment is basically the same as the structure of the molten resin supply system 2 according to the second embodiment. However, the vertical position of the output port 811 of the decontamination machine 81 according to the second embodiment is different from the vertical position of the output port 821 of the decontamination machine 82 according to the third embodiment. Therefore, the shape of the tube 42 of the connecting device 20 according to the second embodiment is different from the shape of the tube 421 of the connecting device 30 according to the third embodiment.

[0125] The structure of the connecting device 30 according to the third embodiment is as follows. That is, as... Figure 5As shown, the connecting device 30 is a device consisting of piping that connects the cleaning machine 82, which is disposed on the first side of the connecting direction, and the injection molding machine 90, which is disposed on the second side. The connecting device 30 consists of pipes 41, 421, 43 and 44, swivel joints 51 to 53, and connecting parts 61 and 62, and is a tortuous pipe formed by connecting them.

[0126] Pipe 421 is a metal tube through which molten resin passes, with one end connected to rotary joint 51 and the other end connected to rotary joint 52. Pipe 421 has a curved shape that allows molten resin flowing from the upper side to the lower side in the vertical direction to flow sequentially towards the second side in the connecting direction and the upper side in the vertical direction, and has a particularly long portion extending in the vertical direction. Furthermore, the structures of pipes 41, 43, and 44, rotary joints 51 to 53, and connecting parts 61 and 62 are as described above. Figure 4 The pipes 41, 43, and 44, the rotary joints 51 to 53, and the connecting parts 61 and 62 in the connecting device 20 shown in the second embodiment have the same structure, so the description is omitted.

[0127] <Comparison between Embodiment 2 and Embodiment 3> like Figure 4 and Figure 5 As shown, the connecting device 30 in the third embodiment differs from the connecting device 20 in the second embodiment. The output port 821 of the cleaning machine 82 is positioned vertically on the same horizontal line as the input port 911 of the injection molding machine 90. Therefore, when the piping of the connecting device 30 is overheated, the portion higher than the vertical positions of the output port 821 and the input port 911 will thermally expand upwards, and the portion lower than the vertical positions of the output port 821 and the input port 911 will thermally expand downwards. At this time, the difference between the degree of upward and downward thermal expansion will not cause thermal stress in the connecting device 30, thus preventing damage such as breakage of the piping. In contrast, as... Figure 4 As shown, in the second embodiment, the connecting device 20 is such that the position of the output port 811 in the vertical direction of the cleaning machine 81 and the position of the input port 911 in the vertical direction of the injection molding machine 90 are not on the same horizontal straight line, thus thermal stress is easily generated in the connecting device 20. Therefore, the structure of the third embodiment is preferred compared to the structure of the second embodiment.

[0128] <Comparison between Embodiment 1 and Embodiment 3> like Figure 1 and Figure 5As shown, the connecting device 30 according to the third embodiment is similar to the connecting device 10 according to the first embodiment in that the output port 821 of the cleaning machine 82 and the input port 911 of the injection molding machine 90 are located on approximately the same horizontal straight line in the vertical direction. However, the connecting device 30 according to the third embodiment differs from the connecting device 10 according to the first embodiment in that the three paths forming the piping extending in the vertical direction are not on the same side relative to the output port 821 and the input port 911 in the vertical direction. That is, among these three paths, some are located on the lower side and some are located on the upper side relative to the output port 821 and the input port 911 in the vertical direction. Therefore, the connecting device 30 according to the third embodiment differs from the connecting device 10 according to the first embodiment in that it is impossible to make the expansion direction of the piping consistent when thermal expansion occurs.

[0129] Specifically, the piping of the connecting device 30 includes a vertically extending path including a rotary joint 51 (hereinafter referred to as the "first path of the third embodiment"), a vertically extending path including a rotary joint 52 and a pipe 421 (hereinafter referred to as the "second path of the third embodiment"), and a vertically extending path including a rotary joint 53 (hereinafter referred to as the "first path of the third embodiment"). The first path of the third embodiment is located lower in the vertical direction relative to the output port 821 and the input port 911, while the third path of the third embodiment is located upper in the vertical direction relative to the output port 821 and the input port 911. Furthermore, the second path of the third embodiment has a portion located upper and a portion located lower in the vertical direction relative to the output port 821 and the input port 911.

[0130] Here, when the piping of the connecting device 30 undergoes thermal expansion, the portion located at the lower side in the vertical direction relative to the output port 821 and the input port 911 will expand thermally from the upper side to the lower side in the vertical direction. Conversely, the portion located at the upper side in the vertical direction relative to the output port 821 and the input port 911 will expand thermally from the lower side to the upper side in the vertical direction. Here, as described above, the difference in the degree of thermal expansion between the upward-extending portion and the downward-extending portion of the piping of the connecting device 30 will not cause thermal stress in the piping of the connecting device 30, thus preventing damage such as breakage at various parts.

[0131] However, the degree of extension due to thermal expansion can sometimes differ between sections with and without a swivel joint. In this regard, the upper portion of the second path in the third embodiment of the piping of the connecting device 30, where the extension occurs upwards due to thermal expansion, has a swivel joint 52, while the third path in the third embodiment has a swivel joint 53. Therefore, the degree of extension due to thermal expansion is less likely to differ. Conversely, the first path in the third embodiment of the connecting device 30, where the extension occurs downwards due to thermal expansion, has a swivel joint 51, but the lower portion of the second path in the third embodiment does not have a swivel joint. Therefore, the extension of the piping during thermal expansion may differ. Hereinafter, this difference will be referred to as "expansion / contraction difference".

[0132] The difference in expansion and contraction of the piping due to the presence or absence of a rotary joint is one of the causes of thermal stress in the connecting device 30. When the difference in expansion and contraction is large, the rotary joint and the pipe may tilt. Compared to the case where the thermal expansion direction is the same, the difference in expansion and contraction due to the presence or absence of a rotary joint has a greater impact on the generation of thermal stress when the thermal expansion direction is not the same. Based on the above, the first embodiment with the same thermal expansion direction is more preferable than the third embodiment where the thermal expansion direction is not the same, in terms of minimizing the impact of the difference in expansion and contraction.

[0133] As mentioned above, the difference in piping expansion and contraction due to the presence or absence of a rotary joint is one of the causes of thermal stress. However, depending on the configuration of the rotary joint, the effect of the difference in piping expansion and contraction can sometimes be suppressed. As a fourth embodiment, this structure will be described below.

[0134] <Fourth Implementation> (Structure of the molten resin supply system) Figure 6 This is a front view showing a portion of the external structure of the molten resin supply system 4 according to the fourth embodiment.

[0135] like Figure 1 and Figure 6 As shown, the structure of the molten resin supply system 4 according to the fourth embodiment is basically the same as the structure of the molten resin supply system 1 according to the first embodiment. However, the configuration of the rotary joint is different.

[0136] The structure of the connecting device 40 according to the fourth embodiment is as follows. That is, as... Figure 6 As shown, the connecting device 40 is a device consisting of piping that connects the cleaning machine 83, which is disposed on the first side of the connecting direction, and the injection molding machine 90, which is disposed on the second side. The connecting device 40 consists of pipes 411 to 414, rotary joints 211 to 213, and connecting parts 31 and 32, and is a tortuous pipe formed by connecting them.

[0137] Pipe 411 is a pipe with one end connected to connecting component 31 and the other end connected to rotary joint 211, and it has the same characteristics as... Figure 1 The pipe 411 has the same structure as the tube 11. That is, the tube 411 is a curved shape that allows the molten resin flowing from the first side to the second side in the connection direction to flow upward in the vertical direction. The tube 412 is a tube with one end connected to the rotary joint 211 and the other end connected to the rotary joint 212. The tube 412 is a curved shape that allows the molten resin flowing from the lower side in the vertical direction to the upper side to flow sequentially to the second side in the connection direction and then to the lower side in the vertical direction.

[0138] Pipe 413 is a pipe with one end connected to rotary joint 212 and the other end connected to rotary joint 213. Pipe 413 has a curved shape that allows molten resin flowing from the upper side to the lower side in the vertical direction to flow sequentially to the second side in the connection direction and the upper side in the vertical direction. Pipe 414 is a pipe with one end connected to rotary joint 213 and the other end connected to connecting member 32. Pipe 414 has a curved shape that allows molten resin flowing from the lower side to the upper side in the vertical direction to flow sequentially to the second side in the connection direction and the lower side in the vertical direction.

[0139] Rotary joint 211 is a rotary joint whose lower end in the vertical direction is connected to pipe 411 and whose upper end is connected to pipe 412. Rotary joint 212 is a rotary joint whose upper end in the vertical direction is connected to pipe 412 and whose lower end is connected to pipe 413. Rotary joint 213 is a rotary joint whose lower end in the vertical direction is connected to pipe 413 and whose upper end is connected to pipe 414. Furthermore, the structures of connecting components 31 and 32 are the same as described above. Figure 1 The connecting components 31 and 32 in the connecting device 10 shown in the first embodiment have the same structure, so the description is omitted.

[0140] <Comparison between Embodiment 1 and Embodiment 4> like Figure 1 and Figure 6 As shown, in the fourth embodiment, the connecting device 40 is similar to the connecting device 10 in the first embodiment, where the output port 831 of the cleaning machine 83 and the input port 911 of the injection molding machine 90 are located on approximately the same horizontal straight line in the vertical direction. Furthermore, in the fourth embodiment, the four paths forming the piping extending vertically are located on the same side (upper side) relative to the output port 831 and the input port 911 in the vertical direction. Therefore, the expansion direction of the piping during thermal expansion is consistent.

[0141] Furthermore, the piping of both the connecting device 10 in the first embodiment and the connecting device 40 in the fourth embodiment exhibits expansion and contraction differences due to the presence or absence of a swivel joint. Specifically, as... Figure 1 As shown, the piping of the connecting device 10 according to the first embodiment includes a path extending in the vertical direction including a rotary joint 21 (hereinafter referred to as "the first path of the first embodiment"), a path extending in the vertical direction formed by the pipe 12 (hereinafter referred to as "the second path of the first embodiment"), a path extending in the vertical direction including a rotary joint 22 (hereinafter referred to as "the third path of the first embodiment"), and a path extending in the vertical direction including a rotary joint 23 (hereinafter referred to as "the fourth path of the first embodiment").

[0142] In the first embodiment, each of the first, third, and fourth paths has a rotary joint 21 to 23, but the second path in the first embodiment does not have a rotary joint. Therefore, when the piping thermally expands, a difference in expansion and contraction may occur in the first and second paths of the first embodiment. Furthermore, a difference in expansion and contraction may also occur in the second and third paths of the first embodiment. In contrast, a difference in expansion and contraction is less likely to occur in the third and fourth paths of the first embodiment. That is, when the piping of the connecting device 10 according to the first embodiment thermally expands, depending on the magnitude of the difference in expansion and contraction, thermal stress may occur, causing the rotary joints 21 and 22 respectively disposed in the first and third paths of the first embodiment to tilt.

[0143] And, as Figure 6 As shown, in the piping of the connecting device 40 according to the fourth embodiment, there are a path extending in the vertical direction including a rotary joint 211 (hereinafter referred to as "the first path of the fourth embodiment"), a path extending in the vertical direction including a rotary joint 212 (hereinafter referred to as "the second path of the fourth embodiment"), a path extending in the vertical direction including a rotary joint 213 (hereinafter referred to as "the third path of the fourth embodiment"), and a path extending in the generation direction formed by the pipe 414 (hereinafter referred to as "the fourth path of the fourth embodiment").

[0144] In the fourth embodiment, each of the first to third paths has a rotary joint 211 to 213, but in the fourth path of the fourth embodiment, there is no rotary joint. Therefore, when the piping expands thermally, a difference in expansion and contraction may occur in the third and fourth paths of the fourth embodiment, but a difference in expansion and contraction is less likely to occur in the first and second paths of the fourth embodiment. Furthermore, a difference in expansion and contraction is also less likely to occur in the second and third paths of the fourth embodiment. That is, when thermal expansion occurs in the piping of the connecting device 40 according to the fourth embodiment, depending on the magnitude of the difference in expansion and contraction, thermal stress may be generated, causing the rotary joint 213 disposed in the third path of the fourth embodiment to tilt.

[0145] As described above, when adjacent paths in a piping system are combinations of paths with and without swivel joints, expansion differences are easily generated. Conversely, when adjacent paths in a piping system are combinations of paths with swivel joints or combinations of paths without swivel joints (not shown), expansion differences are less likely to occur. In this regard, when comparing the first and fourth embodiments, the fourth embodiment, which has only one combination of paths with and without swivel joints, is more preferable than the first embodiment, which has two combinations of paths with and without swivel joints.

[0146] <Fifth Implementation> (Structure of the molten resin supply system) Figure 7 and Figure 8 This is a diagram showing a portion of the external structure of the molten resin supply system 5 according to the fifth embodiment. Figure 7 The image shows a front view of a portion of the molten resin supply system 5, viewed from the front to the rear in a front-to-back direction. Furthermore, in... Figure 8 The diagram shows a plan view of the molten resin supply system 5 viewed from the top to the bottom in a vertical direction.

[0147] The structure of the molten resin supply system 5 according to the fifth embodiment is basically the same as that of the molten resin supply systems 1 to 4 according to the above embodiments, but the orientation of the output port (and connecting component) of the cleaning machine is different from the orientation of the rotation axis of the rotary joint. That is, the orientation of the output port (and connecting component) of the cleaning machine in the molten resin supply systems 1 to 4 according to the above embodiments is the orientation of the molten resin being output from the first side to the second side of the connection direction. Furthermore, the orientation of the rotation axis of the rotary joint of the connecting device in the molten resin supply systems 1 to 4 according to the above embodiments is approximately parallel to the vertical direction.

[0148] In contrast, in the molten resin supply system 5 according to the fifth embodiment, the outlet 841 (and connecting member 511) of the cleaning machine 84 is oriented so that molten resin is output from the lower side to the upper side in the vertical direction. Furthermore, the rotation axes 711 to 713 of the rotary joints 311 to 313 of the connecting device 50 are not parallel to the vertical direction, but are approximately perpendicular to the direction of movement of the heating cylinder (connection direction), that is, approximately parallel to the front-back direction.

[0149] Specifically, the structure of the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment is as follows. That is, as... Figure 7 and Figure 8 As shown, the connecting device 50 is a device consisting of piping that connects the cleaning machine 84, which is disposed on the first side of the connecting direction, and the injection molding machine 90, which is disposed on the second side. The connecting device 50 consists of pipes 611 to 614, swivel joints 311 to 313, and connecting parts 511 and 512, and is a tortuous pipe formed by connecting them.

[0150] Pipe 611 is a pipe with one end connected to connecting member 511 and the other end connected to rotary joint 311. That is, pipe 611 has a curved shape to allow molten resin output from outlet 841 of the decontaminator 84 to flow to rotary joint 311. Pipe 612 is a pipe with one end connected to rotary joint 311 and the other end connected to rotary joint 312. Pipe 612 has a curved shape to allow molten resin flowing from rotary joint 311 to flow to rotary joint 312.

[0151] Pipe 613 is a pipe with one end connected to rotary joint 312 and the other end connected to rotary joint 313. Pipe 613 has a curved shape to allow molten resin flowing from rotary joint 312 to flow into rotary joint 313. Pipe 614 has a curved shape to allow molten resin flowing from rotary joint 313 to flow into inlet 911 of heating cylinder 91.

[0152] Rotary joint 311 is a rotary joint whose rear end in the front-rear direction is connected to pipe 611 and whose front end is connected to pipe 612. Rotary joint 312 is a rotary joint whose front end in the front-rear direction is connected to pipe 612 and whose rear end is connected to pipe 613. Rotary joint 313 is a rotary joint whose rear end in the front-rear direction is connected to pipe 613 and whose front end is connected to pipe 614. Furthermore, the structures of connecting parts 511 and 512 are the same as those shown in the first to fourth embodiments described above, therefore, their description is omitted.

[0153] <Comparison of Embodiments 1 to 4 with Embodiment 5> As described above, the rotation axes of the rotary joints of the connecting devices of the molten resin supply systems according to the first to fourth embodiments are all generally parallel to the vertical direction. In contrast, the rotation axes 711 to 713 of the rotary joints 311 to 313 of the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment are not parallel to the vertical direction, but are generally parallel to the front-back direction.

[0154] By setting the orientation of the rotary joint's rotation axis differently as described above, the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment has the following advantages over the connecting devices of the molten resin supply systems according to the first to fourth embodiments. That is, regardless of the embodiment, manufacturing errors will occur in the connecting device, but these manufacturing errors can sometimes cause bending moments applied inside the rotary joint. When bending moments are applied inside the rotary joint, it can sometimes lead to reduced durability and damage to the rotary joint.

[0155] Manufacturing errors in the connecting device can include, for example, deviations in the length of the pipe constituting the connecting device in the vertical direction, axial offsets in the rotary joint constituting the connecting device, and positional offsets in the vertical direction between one end and the other end of the piping constituting the connecting device. Methods for suppressing these manufacturing errors include improving the precision of each step in the manufacturing process, but this leads to increased manufacturing costs. Furthermore, there are limits to the improvement in precision. In contrast, the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment can absorb manufacturing errors even if such errors occur by rotating the rotary joints 311 to 313.

[0156] That is, as manufacturing errors, deviations in the lengths D1 to D4 of pipes 611 to 613, axial offsets (angles θ1 and θ2) of rotary joints 311 and 313, and positional offsets (distance H) of one end and the other end of the piping in the vertical direction may occur. However, these manufacturing errors are absorbed by rotating through rotary joints 311 to 313.

[0157] Thus, according to the fifth embodiment, the connecting device 50 can suppress manufacturing costs compared to improving the accuracy of each process during manufacturing, and can solve the problem of manufacturing errors that cause bending torque applied to the inside of the rotary joints 311 to 313.

[0158] In summary, the connecting device according to the fifth embodiment of the present invention can be implemented in various ways as long as it adopts the following structure.

[0159] That is, the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment is a connecting device that connects the cleaning machine 84 and the injection molding machine 90 together. The cleaning machine 84 outputs the molten resin of the recovery target from the output port 841. The injection molding machine 90 has: a heating cylinder 91 with an input port 911 for inputting the output molten resin and heating the molten resin; and an injection cylinder 92 (see reference). Figure 2 (Separately from heating cylinder 91, the heated molten resin is injected into mold 93 (see reference)) Figure 2 The contaminator 84 and the injection molding machine 90 are connected together by means of a connecting member 511, one end of the piping formed by the pipes 611 to 614 through which the molten resin passes and the rotary joints 311 to 313 is connected to the output port 841 by means of the connecting member 512, and the other end is connected to the input port 911 by means of the connecting member 512.

[0160] Here, the feature may also be that the rotation axes 711 to 713 of the rotary joints 311 to 313 are not parallel to the vertical direction, but are approximately perpendicular to the direction of movement (connection direction) of the heating cylinder 91 (approximately parallel to the front and back direction).

[0161] Therefore, even if manufacturing errors occur in the components of the piping that constitute the connecting device 50, these errors can be absorbed by rotating the rotary joints 311 to 313.

[0162] <Sixth Implementation> (Structure of the molten resin supply system) Figure 9 This is a diagram showing a portion of the external structure of the molten resin supply system 6 according to the sixth embodiment. Figure 9 The diagram shows a plan view of the molten resin supply system 6 viewed from the top to the bottom in a vertical direction.

[0163] The structure of the connecting device 60 of the molten resin supply system 6 according to the sixth embodiment is basically the same as the structure of the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment. However, the length of a portion of the pipe, the positional relationship between one end of the pipe and the other end, and the positional relationship of the three rotary joints are different.

[0164] The structure of the connecting device 60 according to the sixth embodiment is as follows. That is, as... Figure 9 As shown, the connecting device 60 is a device consisting of piping that connects the cleaning machine 85, which is disposed on the first side of the connecting direction, and the injection molding machine 90, which is disposed on the second side. The connecting device 60 consists of pipes 611, 614, 622 and 623, rotary joints 311 to 313, and connecting parts 511 and 512, and is a tortuous pipe formed by connecting them.

[0165] Furthermore, the imaginary straight line L1 connecting one end of the piping to the other end is approximately parallel to the direction of movement of the heating cylinder 91 (connection direction). Also, the imaginary straight line L1 is approximately orthogonal to the respective rotation axes 711 to 713 of the rotary joints 311 to 313. Furthermore, the imaginary straight line L2 connecting the rotary joints 311 to 313 is not parallel to the imaginary straight line L1 (i.e., not parallel to the connection direction).

[0166] Here, in the connecting device of each embodiment, the portion of the piping that includes a swivel joint disposed on the first side in the connecting direction is designated as the first piping section, and the portion that includes a swivel joint disposed on the second side in the connecting direction is designated as the third piping section. Furthermore, the portion that includes a swivel joint disposed between the first piping section and the third piping section is designated as the second piping section.

[0167] In the piping of the connecting device 60 according to the sixth embodiment, the length D11 of the first piping section including the rotary joint 311 in the longitudinal direction is shorter than the length D12 of the second piping section including the rotary joint 312 in the longitudinal direction. Furthermore, the length D13 of the third piping section including the rotary joint 313 in the longitudinal direction is also shorter than the length D12 of the second piping section in the longitudinal direction. Specifically, the lengths D11 of the first piping section and D13 of the third piping section in the longitudinal direction are preferably 30% or less of the length of the second piping section. Moreover, considering safety, the lengths D11 of the first piping section and D13 of the third piping section in the longitudinal direction are preferably 20% or less of the length of the second piping section.

[0168] <Comparison between Embodiment 5 and Embodiment 6> The pipe 622 of the connecting device 60 of the molten resin supply system 6 is longer than the pipe 612 of the connecting device 50 of the molten resin supply system 5. Specifically, the length of the portion of the pipe 622 of the connecting device 60 of the molten resin supply system 6 that forms part of the second piping is longer than the length of the portion of the pipe 612 of the connecting device 50 of the molten resin supply system 5 that forms part of the second piping.

[0169] Furthermore, the pipe 623 of the connecting device 60 of the molten resin supply system 6 is longer than the pipe 613 of the connecting device 50 of the molten resin supply system 5. Specifically, the length of the portion of the pipe 623 of the connecting device 60 of the molten resin supply system 6 that forms part of the second piping is longer than the length of the portion of the pipe 613 of the connecting device 50 of the molten resin supply system 5 that forms part of the second piping.

[0170] Furthermore, the positional relationship of the rotary joints 311 to 313 of the connecting device 60 of the molten resin supply system 6 in the longitudinal direction differs from that of the rotary joints 311 to 313 of the connecting device 50 of the molten resin supply system 5 in the longitudinal direction. Specifically, as follows... Figure 9 As shown, the positional relationship of the rotary joints 311 to 313 of the molten resin supply system 6 in the front-rear direction is such that the imaginary straight line L2 is not parallel to the imaginary straight line L1 (i.e., not parallel to the connection direction). In contrast, as... Figure 8 As shown, the positional relationship of the rotary joints 311 to 313 of the molten resin supply system 5 in the front-back direction is such that the imaginary straight line L21 connecting the rotary joints 311 to 313 is approximately parallel to the connection direction.

[0171] The connecting device 60 of the molten resin supply system 6 according to the sixth embodiment having this structure has the following advantages over the connecting device 50 of the molten resin supply system 5 according to the fifth embodiment. That is, as... Figure 8 and Figure 9 As shown by the dashed lines, thermal deformation occurs in the piping of the connecting devices 50 and 60 in each embodiment, as indicated by the arrows. Moreover, if the piping flexes due to this thermal deformation, it can sometimes cause a bending moment applied inside the rotary joint.

[0172] In contrast, the connecting device 60 according to the sixth embodiment has the aforementioned relationship between the lengths D11 of the first piping section in the longitudinal direction, D12 of the second piping section in the longitudinal direction, and D13 of the third piping section in the longitudinal direction, thus allowing for an increase in the amount of thermal deformation generated in the piping. Therefore, compared to the connecting device 50 according to the fifth embodiment, the connecting device 60 according to the sixth embodiment is less prone to piping deflection caused by thermal deformation.

[0173] In summary, the connecting device according to the sixth embodiment of the present invention can be implemented in various ways as long as it adopts the following structure.

[0174] That is, the connecting device 60 of the molten resin supply system 6 according to the sixth embodiment is a connecting device that connects a cleaning machine 85 and an injection molding machine 90 together. The cleaning machine 85 outputs the molten resin of the recovery target from the output port 851. The injection molding machine 90 has: a heating cylinder 91 with an input port 911 for inputting the output molten resin and heating the molten resin; and an injection cylinder 92 (see reference). Figure 2 (Separately from heating cylinder 91, the heated molten resin is injected into mold 93 (see reference)) Figure 2The contaminator 85 and the injection molding machine 90 are connected together by means of a connecting member 511, a connecting member 511, a connecting member 512, a connecting member 512, a connecting member 513, a connecting member 611, a connecting member 611, a connecting member 614, a connecting member 62 ...4, a connecting member 623, a connecting member 614, a connecting member 622, a connecting member 614, a connecting member 623, a connecting member 614, a connecting member 622, a connecting member 614, a connecting member 623, a connecting member 614, a

[0175] Here, it can also be characterized in that the imaginary straight line L1 connecting one end of the piping and the other end is approximately parallel to the direction of movement (connection direction) of the heating cylinder 91.

[0176] Furthermore, its characteristic can also be that the imaginary straight line L1 connecting one end of the piping and the other end is approximately orthogonal to the rotation axes 711 to 713 of the rotary joints 311 to 313, respectively.

[0177] Furthermore, the feature may also be that the length D11 of the first piping section, which includes the rotary joint 311 closest to the end connected to the outlet 851, and the length D13 of the third piping section, which includes the rotary joint 313 furthest from the end connected to the outlet 851, are respectively less than 30% of the length D12 of the second piping section, which includes the rotary joint 312 disposed between the first piping section and the third piping section.

[0178] Therefore, the thermal deformation generated in the piping is easily absorbed, thus reducing the likelihood of piping deflection due to thermal deformation.

[0179] <Seventh Implementation> (Structure of the molten resin supply system) Figure 10 Figures (A) and (B) are both diagrams showing a portion of the external structure of the molten resin supply system 7 according to the seventh embodiment. Figure 10 (A) and (B) show front views of the molten resin supply system 7 viewed from the front to the rear in the front-rear direction. Additionally, in Figure 10 (A) shows an example where the position of the output port 861 of the cleaning machine 86 relative to the heating cylinder 91 of the injection molding machine 90 is on the first side of the connection direction. Furthermore, in Figure 10 (B) shows an example where the position of the output port 861 of the cleaning machine 86 relative to the heating cylinder 91 of the injection molding machine 90 is the second side of the connection direction.

[0180] The structure of the connecting device 70 according to the seventh embodiment is as follows. That is, as... Figure 10As shown in (A) and (B), the connecting device 70 is a device consisting of piping that connects the output port 861 of the cleaning machine 86 located on the upper side in the vertical direction to the injection molding machine 90 located on the lower side. The connecting device 70 consists of pipes 631, 632, 633 and 634, rotary joints 311 to 313 and connecting parts 512 and 521, and is a tortuous pipe formed by connecting them.

[0181] The structure of the molten resin supply system 7 in the seventh embodiment is basically the same as that of the molten resin supply systems 5 and 6 in the fifth and sixth embodiments described above. However, as described above, the position of the output port 861 of the cleaning machine 86 in the vertical direction is different.

[0182] This structure is, for example, a structure that can be adopted when there are space constraints in the configuration of devices as described below. That is, as... Figure 10 As shown in (A) and (B), in the injection molding machine 90, the motor, etc., 94 needs to be positioned on the second side in the connection direction of the heating cylinder 91, and the mold 93 needs to be positioned on the first side. In this case, it is difficult to ensure sufficient space near the mold 93 for arranging the connecting device 70. For example, if the output port 861 of the cleaning machine 86 is arranged on the lower side in the vertical direction in order to arrange the connecting device 70 near the mold 93, it is difficult to ensure sufficient maintenance space for the injection molding machine 90.

[0183] Based on the above, considering the maintainability of the injection molding machine 90, the output port 861 of the cleaning machine 86 is preferably positioned on the upper side in the vertical direction relative to the injection molding machine 90 and the connecting device 70. Furthermore, considering ensuring maintenance space and avoiding interference with the motor 94, the output port 861 of the cleaning machine 86 is preferably positioned away from the motor 94 (the first side in the connecting direction). That is, with... Figure 10 Compared to the structure shown in (B), the preferred option is... Figure 10 The structure shown in (A) reduces the risk of interference between the connecting device 70 and the motor 94 due to the extension and retraction of the connecting device 70.

[0184] Symbol Explanation 1, 2, 3, 4, 5, 6, 7 - Molten resin supply system; 10, 20, 30, 40, 50, 60, 70 - Connecting devices; 11, 12, 13, 14, 41, 42, 43, 44, 411, 412, 413, 414, 421, 611, 612, 613, 614, 622, 623, 631, 632, 633, 634 - Pipes; 21, 22, 23, 51, 52, 53, 2 11, 212, 213, 311, 312, 313 - Rotary joints; 31, 32, 61, 62, 511, 512, 521 - Connecting components; 80, 81, 82, 83, 84, 85, 86 - Stain removers; 90 - Injection molding machine; 91 - Heating cylinder; 92 - Injection cylinder; 93 - Mold; 94 - Motor, etc.; 801, 811, 821, 831, 841, 861 - Output ports; 911 - Input ports.

Claims

1. A connecting device for connecting an output device and an injection molding machine, the output device discharging molten resin of a recyclable object from an output port, the injection molding machine comprising: a heating cylinder having an input port for inputting the output molten resin and for heating the molten resin; and an injection cylinder, independent of the heating cylinder, for injecting the heated molten resin into a mold, wherein one end of a piping formed by a pipe through which the molten resin passes and a rotary joint is connected to the output port and the other end is connected to the input port, thereby connecting the output device and the injection molding machine together.

2. The connecting device according to claim 1, characterized in that, The number of rotary joints provided in the connecting device is 3.

3. The connecting device according to claim 1, characterized in that, The rotary joint has a sealing component with a preset heat resistance temperature and durability pressure.

4. The connecting device according to claim 1, characterized in that, The connecting device heats the molten resin passing through the piping by heating the piping itself.

5. The connecting device according to claim 4, characterized in that, The connecting device heats the piping via a belt heater.

6. The connecting device according to claim 1, characterized in that, The rotary joint is rotatable via a sliding bearing, and a portion of the molten resin is used as a lubricant for the sliding bearing.

7. The connecting device according to claim 1, characterized in that, The rotation axis of the rotary joint is not parallel to the vertical direction, and is approximately perpendicular to the direction of movement of the heating cylinder.

8. The connecting device according to claim 1, characterized in that, An imaginary straight line connecting one end of the piping to the other end is approximately parallel to the direction of movement of the heating cylinder.

9. The connecting device according to claim 1, characterized in that, The imaginary straight line connecting one end and the other end of the piping is approximately orthogonal to the rotation axis of the rotary joint.

10. The connecting device according to claim 2, characterized in that, The lengths of the first piping section, including the swivel joint closest to one end, and the lengths of the third piping section, including the swivel joint furthest from that end, are each less than 30% of the length of the second piping section, including the swivel joint disposed between the first piping section and the third piping section.

11. A molten resin supply system, characterized in that, Equipped with the output device, the injection molding machine, and the connecting device as described in claim 1, The position of the output port of the output device is fixed, and the position of the input port of the heating cylinder moves according to the movement of the heating cylinder.

12. A molten resin supply system, characterized in that, Equipped with the output device, the injection molding machine, and the connecting device as described in claim 1, Even if the output device moves relative to the injection molding machine, the imaginary straight line connecting the rotation axes of the three rotary joints connected by the two tubes will not be a straight line when viewed from the top and bottom, or, a process is performed to ensure that it will not be a straight line when viewed from the top and bottom.

13. The molten resin supply system according to claim 11 or 12, characterized in that, The output device or the injection molding machine controls the reduction of the internal pressure based on the magnitude of the internal pressure of the rotary joint.

14. The molten resin supply system according to claim 13, characterized in that, As part of the control, the output device or the injection molding machine controls the pressure when the molten resin is output from the output port.

15. The molten resin supply system according to claim 14, characterized in that, As a control, the output device or the injection molding machine controls at least one of the output of the molten resin from the output device and the input of the molten resin to the injection molding machine.

16. The molten resin supply system according to claim 13, characterized in that, The output device calculates the magnitude of the internal pressure based on information detected at the inlet and outlet of the molten resin in the rotary joint.

17. The molten resin supply system according to claim 11 or 12, characterized in that, The output port of the output device and the input port of the injection molding machine are each located on the same or approximately the same horizontal straight line in the vertical direction.

Images