Injection molding machine

Abstract

To improve a throughput of a molded product manufactured by using an injection molding machine.SOLUTION: An injection molding machine 1 includes: a cylinder 11; a hopper 14 attached to the cylinder 11 for supplying a molding material into the cylinder 11; and a material feeding device 4 for supplying the molding material into the hopper 14. The tank 31 of the material feeding device 4 is connected to the hopper 14 via a hose 54. The material feeding device 4 is connected via a hose 51 to a container 57 that stores the molding material. The molding material can be transferred from the container 57 to the material feeding device 4 through the hose 51 and from the tank 30 of the material feeding device 4 to the hopper 14 through the hose 54.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an injection molding machine and a material supply device.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2002-66712 (Patent Document 1) describes a technique related to a metal injection molding machine using alloy chips as a molding material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An injection molding machine for forming a molded product of a desired shape is known. A general injection molding machine is composed of an injection device and a mold clamping device. The injection device melts the molding material and supplies the melted molding material to the mold clamping device.

[0005] The injection device has a cylinder incorporating a screw and a hopper for supplying the molding material to the cylinder. When the molding material is supplied from the hopper into the cylinder, the molding material in the hopper decreases. Therefore, it is necessary to supply the molding material to the hopper of the injection device. When supplying the molding material stored in a container to the hopper of the injection device, it is necessary to convey the molding material from the container to the hopper of the injection device. However, if a problem occurs in the conveyance, it may be necessary to put the injection molding machine in a standby state. This reduces the operating rate of the injection molding machine and the throughput of the molded products manufactured using the injection molding machine.

[0006] Other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

Means for Solving the Problems

[0007] According to one embodiment, the injection molding machine includes a cylinder, a first hopper attached to the cylinder for supplying molding material into the cylinder, and a material supply device for supplying the molding material to the first hopper. The material supply device has a first container for storing the molding material, and the first container of the material supply device is connected to the first hopper via a first tubular member. The material supply device is connected to a second container storing the molding material via a second tubular member. The molding material can be transported from the second container to the material supply device through the second tubular member, and the molding material can be transported from the first container of the material supply device to the first hopper through the first tubular member. [Effects of the Invention]

[0008] According to one embodiment, the throughput of molded products manufactured using an injection molding machine can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing the general configuration of an injection molding machine according to one embodiment. [Figure 2] This is a side view of a material supply device according to one embodiment. [Figure 3] This is a cross-sectional view of a material supply device according to one embodiment. [Figure 4] Figure 3 is a partially enlarged cross-sectional view showing an enlarged portion of the material supply device. [Figure 5] This is a cross-sectional view of a container for storing molding material. [Figure 6] This is a magnified cross-sectional view showing a portion of the hopper of an injection molding device. [Figure 7] This is a diagram illustrating the operation of the material supply device. [Figure 8] This is a diagram illustrating the operation of the material supply device. [Figure 9] This table illustrates an example of automatic control for a material supply device. [Figure 10] It is an explanatory diagram showing the situation inside the container storing the molding material. [Figure 11] It is an explanatory diagram showing the situation inside the container storing the molding material. [Figure 12] It is a schematic diagram showing the schematic configuration of the injection molding machine of the study example. [Figure 13] It is a schematic diagram showing the schematic configuration of the injection molding machine of other embodiments.

Embodiments for Carrying out the Invention

[0010] Hereinafter, the embodiments will be described in detail based on the drawings. In all the drawings for explaining the embodiments, members having the same function are denoted by the same reference numerals, and the repeated description thereof is omitted. Further, in the following embodiments, the description of the same or similar parts is not repeated as a principle except when particularly necessary.

[0011] (Embodiment 1) <Regarding the Configuration of the Injection Molding Machine> FIG. 1 is a schematic diagram showing the schematic configuration of the injection molding machine 1 of the present embodiment. The injection molding machine 1 shown in FIG. 1 is composed of an injection device 2, a mold clamping device 3, and a material supply device 4.

[0012] <Regarding the Configuration of the Injection Device> First, referring to FIG. 1, the schematic configuration of the injection device 2 will be described. The injection device 2 shown in FIG. 1 includes a cylinder 11, a screw 12 rotatably disposed in the cylinder 11, a drive mechanism 13 for driving the screw 12 in the cylinder 11, and a hopper (molding material input part, molding material supply part) 14 disposed on the rear end side of the cylinder 11. The hopper 14 is connected to an opening (material supply port) 15 on the upper surface of the cylinder 11 so that the molding material (raw material for manufacturing a molded product) can be supplied from the hopper 14 into the cylinder 11. A heating mechanism such as a heater 16 is provided inside or on the outer periphery of the cylinder 11.

[0013] <Regarding the Configuration of the Mold Clamping Device> Next, referring to FIG. 1, the schematic configuration of the mold clamping device 3 will be described. The mold clamping device 3 shown in FIG. 1 has a fixed fixed platen 21, a movable movable platen 22, and a mold clamping mechanism (not shown) for moving the movable platen 22. Therefore, the mold clamping device 3 can variably control the distance between the movable platen 22 and the fixed platen 21. Between the movable platen 22 and the fixed platen 21, a mold 23 and a mold 24 can be arranged. The mold 23 is attached to the fixed platen 21, and the mold 24 is attached to the movable platen 22. Therefore, the mold 24 attached to the movable platen 22 can move together with the movable platen 22. The mold clamping mechanism (not shown) can move the mold 24 attached to the movable platen 22 forward or backward with respect to the mold 23 attached to the fixed platen 21. When the mold 24 moves forward and contacts the mold 23, the molds 23 and 24 are in the "mold closed" state, and when the mold 24 moves backward and separates from the mold 23, the molds 23 and 24 are in the "mold open" state. When the molds 23 and 24 are in the mold closed state, a cavity 25 is formed between the mold 23 and the mold 24. The cavity 25 is a space for molding. The tip of the cylinder 11 of the injection device 2 is connected to the fixed platen 21 of the mold clamping device 3. Specifically, the tip of the cylinder 11 is connected to the fixed platen 21 via the nozzle 18. By injecting the molten molding material from the cylinder 11 of the injection device 2 into the cavity 25 of the molds 23 and 24 through the nozzle 18, a molded product is formed.

[0014] <Regarding the operation of the injection molding machine> Next, the outline of the operation of the injection molding machine 1 shown in FIG. 1 will be described.

[0015] The hopper 14 of the injection molding device 2 stores the molding material, and a predetermined amount of molding material is supplied (injected) from the hopper 14 to the cylinder 11 through the opening 15. The molding material supplied from the hopper 14 to the cylinder 11 is a solid material and is in the shape of a chip. As the molding material, metal chips such as magnesium (Mg) chips can be used. The molding material supplied from the hopper 14 to the cylinder 11 is melted as it is fed forward by the rotation of the screw 12 within the cylinder 11. The melting of the molding material can occur due to heating by a heating mechanism such as a heater 16 or due to the shear force caused by the rotation of the screw 12. The molten molding material will be referred to as "molten material" below. The molten material may also be in a semi-molten state.

[0016] The molten material sent forward within the cylinder 11 is stored in the tip of the cylinder 11 (storage section 17), and the screw 12 retracts as a result. Alternatively, the molten material is stored in the storage section 17 created by the retraction of the screw 12 at the tip of the cylinder 11. As a result, the storage section 17 contains the amount of molten material necessary for injection. This state corresponds to Figure 1, in which the molten material stored in the storage section 17 is shown with dot hatching.

[0017] Next, the screw 12 is moved forward within the cylinder 11 without rotating. This causes the molten material stored in the reservoir 17 of the cylinder 11 to be injected through the nozzle 18 into the cavity 25 of the closed molds 23 and 24. The screw 12 continues to apply pressure to the molten material even after injecting it into the cavity 25. The molds 23 and 24 are cooled while maintaining the pressure on the molten material in the cavity 25.

[0018] While the molds 23 and 24 are cooling, the above-described operations are performed in preparation for the next injection. Specifically, a predetermined amount of molding material is supplied from the hopper 14 to the cylinder 11 through the opening 15, and the molding material supplied into the cylinder 11 is melted while being fed forward by the rotation of the screw 12, and the amount of molten material required for the next injection is stored in the tip of the cylinder 11 (storage section 17). At this time, as described above, the molten material is stored in the storage section, and the screw 12 retracts as a reaction. The process of feeding the molten material forward while retracting the screw 12 so that the molten material can be injected is called "metering".

[0019] After cooling the molds 23 and 24 to a temperature below the solidification temperature of the molten material in the cavity 25, the clamping device 3 is operated to open the molds 23 and 24, and the molded product is removed. The molded product is formed when the molten material in the cavity 25 of the molds 23 and 24 solidifies.

[0020] Next, the clamping device 3 is operated to close the molds 23 and 24. Then, as described above, the screw 12 is moved forward within the cylinder 11 without rotating it, thereby injecting (extracting) the molten material stored in the reservoir 17 of the cylinder 11 into the cavities 25 of the closed molds 23 and 24 via the nozzle 18.

[0021] By repeating this process, it is possible to continuously manufacture molded products of the same shape. Therefore, by repeatedly operating the injection molding machine 1, it is possible to mass-produce molded products of the desired shape.

[0022] Furthermore, as the weighing process is repeated, the amount of molding material in the hopper 14 decreases. Therefore, when the amount of molding material in the hopper 14 becomes low, molding material is transported and supplied from the material supply device 4 to the hopper 14. The material supply device 4 will be described below.

[0023] <About the material supply device> As described above, the injection molding machine 1 of this embodiment is further equipped with a material supply device 4 in addition to the injection device 2 and the clamping device 3. The material supply device 4 is used to supply molding material to the hopper 14 of the injection device 2.

[0024] Figure 2 is a side view of the material supply device 4, and Figure 3 is a cross-sectional view (side cross-sectional view) of the material supply device 4. Figure 4 is a partially enlarged cross-sectional view showing a part of the material supply device 4 (near the hopper 34). Figure 5 is a cross-sectional view (side cross-sectional view) of the container 57 shown in Figure 1. Figure 6 is a partially enlarged cross-sectional view showing a part of the hopper 14 (upper part) of the injection device 2 shown in Figure 1.

[0025] As shown in Figures 1 to 4, the material supply device 4 comprises a tank (storage container, storage section) 31 which is a container for storing molding material, a frame (support base) 32 which supports the tank 31, a lid (ceiling section) 33 which constitutes the upper part of the tank 31, and a hopper 34 attached to the lid 33. In Figures 1 and 3, for ease of understanding, the molding material stored in the tank 31 is shown with dot hatching and labeled with reference numeral 30.

[0026] The interior (internal space) of the hopper 34 is divided into two areas (spaces) 36 and 37 by a filter member 35 such as a wire mesh (see Figure 4). Of the areas 36 and 37, area 36 is located on the lower side and area 37 is located on the upper side, with the filter member 35 positioned at the boundary between area 36 and area 37. The filter member 35 is designed so that molding material cannot pass through, but air can. Therefore, within the hopper 34, molding material cannot move between area 36 and area 37, but air can move. A sensor 41 is attached to the tank 31. The sensor 41 can detect information related to the amount of molding material 30 in the tank 31. For example, the sensor 41 can detect the position of the upper surface of the molding material 30 in the tank 31, thereby detecting the amount of molding material in the tank 31.

[0027] The hopper 34 is connected to an opening 42 provided in the lid 33, and a damper (opening / closing mechanism) 43 is provided in this opening 42. The damper 43 can be switched between a closed state and an open state. When the damper 43 is in the open state, the opening 42 is not closed by the damper 43 and is open, so the area 36 of the hopper 34 and the inside (internal space) of the tank 31 are in communication through the opening 42. In this state, it is possible to move the molding material from the area 36 of the hopper 34 into the tank 31. On the other hand, when the damper 43 is in the closed state, the opening 42 is closed by the damper 43, so the area 36 of the hopper 34 and the inside of the tank 31 are blocked by the damper 43. In this state, it is not possible to move the molding material from the area 36 of the hopper 34 into the tank 31.

[0028] Two tubular members, hose 51 and hose 52, are connected to the hopper 34. One end of hose 51 is connected to a material supply port (opening) 38 provided in area 36 of the hopper 34, allowing molding material to move from hose 51 through the material supply port 38 to area 36 of the hopper 34. The other end of hose 52 is connected to an air intake port (opening) 39 provided in area 37 of the hopper 34, allowing air to be drawn into the hopper 34 through hose 52 and the air intake port 39.

[0029] The other end of the hose 51 (the end opposite to the side connected to the hopper 34) is connected to a nozzle 56, such as a suction nozzle, which is inserted into a container (storage container, drum) 57 in which the molding material is stored (see Figure 5). Therefore, the container 57 and the hopper 34 are connected via the hose 51. In Figures 1 and 5, for ease of understanding, the molding material stored in the container 57 is shown with dot hatching and labeled with reference numeral 30. More specifically, the container 57 is a drum. As can be seen from Figure 5, the tip of the nozzle 56 is inserted (embedded) in the molding material 30 inside the container 57. This makes it possible to transport the molding material 30 from the container 57 to the hopper 34 of the material supply device 4 through the nozzle 56 and the hose 51.

[0030] The capacity (volume) of the tank 31 of the material supply device 4 is greater than the capacity (volume) of the container 57. That is, the maximum amount of molding material that can be stored in the tank 31 is greater than the maximum amount of molding material that can be stored in the container 57. Therefore, the tank 31 can store a larger amount of molding material than the maximum amount that can be stored in the container 57. Also, the weight of the molding material is proportional to its volume. For this reason, the maximum weight of molding material that can be stored in the tank 31 is greater than the maximum weight of molding material that can be stored in the container 57. For example, the capacity of the tank 31 can be twice or more (more preferably about 3 to 5 times) the capacity of the container 57.

[0031] The other end of hose 52 (the end opposite to the side connected to hopper 34) is connected to a switching valve (switching unit) 58 (see Figure 1). In other words, hopper 34 and switching valve 58 are connected via hose 52. Also, blower 59 and switching valve 58 are connected via tubular member hose 53 (see Figure 1). In other words, one end of hose (tubular member) 53 is connected to switching valve 58, and the other end of hose 53 (the end opposite to the side connected to switching valve 58) is connected to the suction side of blower 59.

[0032] The tank 31 of the material supply device 4 and the hopper 14 of the injection device 2 are connected via a tubular member called a hose 54 (see Figure 1). Specifically, one end of the hose (tubular member) 54 is connected to a material discharge port (opening) 44 provided in the tank 31 (see Figures 2 and 3), and the other end of the hose 54 (the end opposite to the one connected to the tank 31) is connected to a material supply port (opening) 64 provided in the hopper 14 (see Figure 6). This allows the molding material in the tank 31 to move from the material discharge port 44 to the hose 54, making it possible to transport the molding material from the tank 31 to the hopper 14 via the hose 54. The material discharge port 44 is located at the bottom of the tank 31.

[0033] The hopper 14 and the switching valve 58 of the injection device 2 are connected via a tubular member called a hose 55. That is, one end of the hose (tubular member) 55 is connected to a suction port (opening) 65 provided in the hopper 14, and the other end of the hose 55 (the end opposite to the side connected to the hopper 14) is connected to the switching valve 58.

[0034] Here, the connection relationship between the hopper 14 and the hoses 54 and 55 will be explained with reference to Figure 6. As shown in Figure 6, the interior (internal space) of the hopper 14 has two areas (spaces): area 61 and area 62. Area 61 has a material supply port 64, and area 62 has an air intake port 65. One end of hose 54 is connected to the material supply port 64. This allows molding material to be supplied to area 61 of the hopper 14 through hose 54 and the material supply port 64. One end of hose 55 is connected to the air intake port 65. This allows air to be drawn into the hopper 14 through the air intake port 65 and hose 55. A filter member 63, such as a wire mesh, is placed at the boundary between area 61 and area 62. The filter member 63 is designed so that molding material cannot pass through, but air can. Of areas 61 and 62, area 61 is located on the lower side, and area 62 is located on the upper side. Therefore, within the hopper 14, the molding material cannot move between area 61 and area 62, but air can move. The hopper 14 is also equipped with a sensor 71. The sensor 71 can detect information related to the amount of molding material in the hopper 14. For example, the sensor 71 can detect the position of the upper surface of the molding material in the hopper 14, and thereby detect whether the amount of molding material in the hopper 14 is above a certain threshold.

[0035] The switching valve 58 can switch between three states: one in which hose 53 is connected to hose 55 (switching position A), one in which hose 53 is connected to hose 52 (switching position C), and one in which hose 53 is not connected to either hose 52 or 55 (switching position B). In the following, the state in which hose 53 is connected to hose 55 will be referred to as switching position A, the state in which hose 53 is not connected to either hose 52 or 55 will be referred to as switching position B, and the state in which hose 53 is connected to hose 52 will be referred to as switching position C.

[0036] The control unit 5 of the injection molding machine 1 can control the switching valve 58 and switch the connection state of the hoses 52, 53, and 55 connected to the switching valve 58. The control unit 5 can also control the blower 59. The control unit 5 can control the operation of the injection molding machine 1, but a separate control unit can be provided to control the switching valve 58 and the blower 59 independently of the control unit that controls the operation of the injection molding machine 1. The control unit 5 includes, for example, a control semiconductor device (processor) and a memory semiconductor device (memory). The injection molding machine 1 or material supply device 4 also has an operation unit (control panel) for various operations and displays, and the control unit 5 can perform various controls based on the information input to the operation unit and the programs and information stored in the control unit 5.

[0037] <Regarding the operation of the material supply device> Next, the operation of the material supply device 4 will be explained. Figures 7 and 8 are explanatory diagrams of the operation of the material supply device 4.

[0038] First, we will explain the operation of transporting the molding material in container 57 to material supply device 4. Hereafter, this operation will be referred to as the first operation. Figure 7 is an explanatory diagram of the first operation.

[0039] In the first operation, the switching valve 58 is first set to the state where hose 53 and hose 52 are connected (switching position C) (step S1 in Figure 7). As a result, the suction side of the blower 59 is connected to the hopper 34 of the material supply device 4 via hose 53, switching valve 58, and hose 52.

[0040] Next, the blower 59 starts blowing air, and the blower 59 sucks air from inside the hopper 34 through hoses 53 and 52 (step S2 in Figure 7). This creates negative pressure inside the hopper 34 (areas 36, 37), causing the damper 43 to close. Consequently, the molding material inside the container 57 is sucked in through the nozzle 56. This is because the nozzle 56 is connected to the hopper 34 through hose 51, so when the blower 59 sucks air inside the hopper 34 through hoses 53 and 52 and the damper 43 closes, the suction force of the blower 59 is transmitted to the nozzle 56 through hose 51. The molding material sucked in through the nozzle 56 by the suction force of the blower 59 is supplied along with air through hose 51 to area 36 of the hopper 34 from the material supply port 38. The air from the molding material and air supplied into area 36 of the hopper 34 is moved to area 37 of the hopper 34 by the suction force of the blower 59, passing through the filter member 35, and is then sent to the blower 59 through the air intake 39 of the hopper 34 via the hose 52, the switching valve 58, and the hose 53 for exhaust. On the other hand, the molding material from the molding material and air supplied into area 36 of the hopper 34 cannot pass through the filter member 35. This is because the multiple openings (holes) in the filter member 35 are sized so that air can pass through but the molding material cannot. Therefore, the molding material supplied into area 36 of the hopper 34 from the material supply port 38 remains in area 36. In this way, the molding material in the container 57 is transported and stored in area 36 of the hopper 34.

[0041] Next, the blower 59 is stopped, and the suction of air from the hopper 34 by the blower 59 is stopped (step S3 in Figure 7). As a result, the nozzle 56 no longer sucks the molding material from the container 57, and the transport of the molding material from the container 57 to the hopper 34 is stopped. Also, because the blower 59 has stopped blowing, the pressure inside the hopper 34 (areas 36, 37) returns to atmospheric pressure, and the damper 43 opens. Consequently, the molding material in area 36 of the hopper 34 falls into the tank 31 through the opening 42 of the lid 33. As a result, the molding material in area 36 of the hopper 34 moves into the tank 31 and is stored in the tank 31.

[0042] Therefore, by performing steps S2 and S3 in order, a predetermined amount of molding material is transported from the container 57 into the tank 31 of the material supply device 4. In steps S2 and S3, the switching valve 58 remains set to switching position C. By repeating steps S2 and S3 as needed, a desired amount of molding material can be transported and stored from the container 57 into the tank 31 of the material supply device 4. The more times steps S2 and S3 are repeated, the greater the amount of molding material transported from the container 57 into the tank 31 of the material supply device 4.

[0043] Next, we will describe the operation of transporting the molding material from the tank 31 of the material supply device 4 into the hopper 14 of the injection device 2. Hereafter, this operation will be referred to as the second operation. Figure 8 is an explanatory diagram of the second operation.

[0044] In the second operation, first, the switching valve 58 is set to the state where hose 53 and hose 55 are connected (switching position A) (step S11 in Figure 8). As a result, the suction side of the blower 59 is connected to the hopper 14 via hose 53, switching valve 58, and hose 55.

[0045] Then, the blower 59 starts blowing air, and the blower 59 sucks air from inside the hopper 14 through hoses 53 and 55 (step S12 in Figure 8). In the second operation, the movement of air and molding material between the hopper 14 and the cylinder 11 of the injection device 2 is blocked. As the blower 59 sucks air from inside the hopper 14 through hoses 53 and 55, the molding material in the tank 31 is sucked out from the material outlet 44 of the tank 31 and transported into the hopper 14 through hose 51. This is because the material outlet 44 of the tank 31 is connected to the hopper 14 through hose 54, so when the blower 59 sucks air from inside the hopper 14 through hoses 53 and 55, the suction force of the blower 59 is transmitted through hose 54 to the material outlet 44 of the tank 31. The molding material, sucked in from the material discharge port 44 of the tank 31 by the suction force of the blower 59, is supplied together with air through the hose 54 to the material supply port 64 of the hopper 14 into the area 61 of the hopper 14. The air, along with the molding material supplied into the area 61 of the hopper 14, is moved by the suction force of the blower 59 through the filter member 63 to the area 62 of the hopper 14, and is then sent to the blower 59 through the intake port 65 of the hopper 14, the hose 55, the switching valve 58, and the hose 53 for exhaust. On the other hand, the molding material, along with the air supplied into the area 61 of the hopper 14, cannot pass through the filter member 63. This is because the multiple openings (holes) in the filter member 63 are sized such that air can pass through but the molding material cannot. Therefore, the molding material supplied from the material supply port 64 of the hopper 14 into area 61 of the hopper 14 cannot move to area 62, and therefore cannot move to the hose 55, remaining in area 61 (and thus in the hopper 14). Also, the molding material already stored in the hopper 14 at the start of the second operation cannot pass through the filter member 63, and therefore cannot move to area 62 of the hopper 14, and therefore cannot move from the hopper 14 to the hose 55, remaining in the hopper 14. In this way, the molding material in the tank 31 of the material supply device 4 is transported to and stored in the hopper 14 of the injection device 2.

[0046] Next, the blower 59 is stopped, and the suction of air into the hopper 14 by the blower 59 is stopped (step S13 in Figure 8). As a result, the molding material in the tank 31 is no longer sucked from the material discharge port 44 to the hose 54, and the transport of the molding material from the tank 31 to the hopper 14 is stopped.

[0047] In the second operation, the movement of air and molding material between the hopper 14 of the injection device 2 and the cylinder 11 is blocked. Therefore, even if the transport of molding material from the tank 31 to the hopper 14 stops, the state in which molding material is stored in the hopper 14 is maintained. In the metering process described above, a predetermined amount of molding material stored in the hopper 14 is supplied from the hopper 14 to the cylinder 11.

[0048] Therefore, by performing steps S11, S12, and S13, a desired amount of molding material can be transported from the tank 31 into the hopper 14 and stored. While step S12 is being performed, the switching valve 58 remains set to switching position A. The longer the duration of step S12 described above, the greater the amount of molding material transported from the tank 31 to the hopper 14. By continuing step S12 for the required time, a desired amount of molding material can be transported from the tank 31 into the hopper 14 and stored.

[0049] As described above, the first and second operations can be performed by controlling the switching valve 58 and the blower 59. Since the state of the switching valve 58 is different for the first and second operations, the first and second operations cannot be performed simultaneously. That is, the second operation cannot be performed while the first operation is in progress, and the first operation cannot be performed while the second operation is in progress.

[0050] Furthermore, in the metering process described above, it is desirable that the second operation is not performed when a predetermined amount of molding material is supplied from the hopper 14 into the cylinder 11. In other words, it is desirable to supply the molding material from the hopper 14 into the cylinder 11 without performing the second operation. This prevents the supply of molding material from the hopper 14 into the cylinder 11 from being hindered by the suction force of the blower 59 generated in the second operation. Therefore, it is possible to prevent the amount of molding material supplied from the hopper 14 into the cylinder 11 from deviating from the planned input amount in the metering process.

[0051] Furthermore, when there is little need to transport molding material from tank 31 to hopper 14 (for example, when a sufficient amount of molding material is stored in hopper 14), it is desirable to perform the first operation to transport the molding material in container 57 into tank 31 of material supply device 4. This increases the amount of molding material stored in tank 31 of material supply device 4. Also, when there is a high need to transport molding material from tank 31 to hopper 14 (for example, when the amount of molding material in hopper 14 falls below a standard value), it is desirable to perform the second operation to transport molding material from tank 31 to hopper 14. This increases the amount of molding material in hopper 14, and allows the supply of molding material from hopper 14 to cylinder 11 in the weighing process to be performed while a sufficient amount of molding material is stored in hopper 14.

[0052] Next, an example of automatic control of the material supply device 4 will be described with reference to Figure 9. Figure 9 is a table illustrating an example of automatic control of the material supply device 4. Based on the information detected by the sensors 41 (41a, 41b) of the material supply device 4 and the sensor 71 of the hopper 14, the control unit 5 controls the switching valve 58 and the blower 59, thereby performing automatic control of the material supply device 4.

[0053] The sensor 41 provided in the material supply device 4 includes a sensor (full sensor) 41a and a sensor (lower limit sensor) 41b. Sensor 41a can detect whether the amount of molding material in the tank 31 is full or not. Here, the amount of molding material in the tank 31 being full corresponds to the state in which the tank 31 is almost filled with molding material and the position of the upper surface of the molding material in the tank 31 has reached a predetermined reference position.

[0054] Furthermore, sensor 41b can detect whether the amount of molding material in tank 31 is above the permissible lower limit (hereinafter referred to as the "lower limit"). Here, the lower limit is set to a level at which, if the amount of molding material in tank 31 falls below that lower limit, it is recommended to replenish the molding material from container 57 into tank 31. In other words, the lower limit is the level that triggers the first action. The lower limit is less than the amount of molding material when the tank is full. The lower limit can also be considered a reference value for the amount of molding material in tank 31.

[0055] Specifically, if the amount of molding material in tank 31 is full, sensor 41a will react (turn ON), and if the amount of molding material in tank 31 is not full, sensor 41a will not react (turn OFF). Also, if the amount of molding material in tank 31 is above the lower limit, sensor 41b will react (turn ON), and if the amount of molding material in tank 31 is below the lower limit, sensor 41b will not react (turn OFF).

[0056] In the material supply device 4, the mounting position of sensor 41b is located lower than the mounting position of sensor 41a. Sensor 41b can be installed, for example, on the side of the tank 31. Sensor 41a can be installed, for example, on the side of the tank 31 or on the lid 33. Alternatively, sensor 41a can be installed near the connection between the tank 31 and the hopper 34.

[0057] A sensor 71 installed in the hopper 14 can detect information related to the amount of molding material in the hopper 14. For example, the sensor 71 can detect the position of the top surface of the molding material in the hopper 14, thereby detecting whether the amount of molding material in the hopper 14 is above a certain threshold. Specifically, if the amount of molding material in the hopper 14 is above a certain threshold, the sensor 71 reacts (ON), and if the amount of molding material in the hopper 14 is below a certain threshold, the full sensor 71 does not react (OFF). Here, the threshold for the amount of molding material in the hopper 14 is set to a level at which, if the amount of molding material in the hopper 14 falls below that threshold, it is recommended to replenish the molding material from the tank 31 to the hopper 14. In other words, the threshold for the amount of molding material in the hopper 14 is the level that triggers the second operation. It is also possible to set a level close to full as the threshold.

[0058] The detection states of sensors 41a and 41b on the material supply device 4 and sensor 71 on the hopper 14 of the injection device 2 can be classified into six states (states 1 to 6) as shown in the table in Figure 9. The control unit 5 controls the switching valve 58 and the blower 59 according to each state.

[0059] In the first state shown in the table in Figure 9, all of the full sensor 71, sensor 41a, and sensor 41b are reacting (ON), so the control unit 5 determines that the amount of molding material in the hopper 14 is above the standard value and that the amount of molding material in the tank 31 is full. In this case, it is not necessary to transport the molding material from the container 57 to the material supply device 4 or to transport the molding material from the tank 31 to the hopper 14. For this reason, in the first state, the control unit 5 switches the switching valve 58 to switching position B and stops the blower 59 without performing the blowing operation. In the first state shown in the table in Figure 9, neither the first operation nor the second operation described above is performed.

[0060] In the second state shown in the table in Figure 9, sensors 71 and 41b are activated (ON), and sensor 41a is not activated (OFF). Therefore, the control unit 5 determines that the amount of molding material in the hopper 14 is above the standard value, and the amount of molding material in the tank 31 is not full but is above the lower limit. In this case, it is not necessary to transport the molding material from the container 57 to the material supply device 4, nor to transport the molding material from the tank 31 to the hopper 14. For this reason, in the second state, the control unit 5 switches the switching valve 58 to switching position B, and stops the blower 59 without performing the blowing operation. In the second state shown in the table in Figure 9, neither the first operation nor the second operation described above is performed.

[0061] In the third state shown in the table of Figure 9, sensor 71 is activated (ON), and sensors 41a and 41b are not activated (OFF). Therefore, the control unit 5 determines that the amount of molding material in hopper 14 is above the standard value, and the amount of molding material in tank 31 is below the lower limit. In this case, it is not necessary to transport the molding material from tank 31 to hopper 14, but it is desirable to transport the molding material from container 57 to material supply device 4. For this reason, in the third state, the control unit 5 performs the first operation described above. That is, in accordance with the first operation described above, the switching valve 58 is switched to switching position C, and the blower 59 is operated. In the third state shown in the table of Figure 9, the first operation described above is performed, and the molding material is transported from container 57 to tank 31 of material supply device 4 and stored in tank 31.

[0062] In the fourth state shown in the table in Figure 9, sensor 71 is unresponsive (OFF) and sensors 41a and 41b are responsive (ON). Therefore, the control unit 5 determines that the molding material in hopper 14 is below the standard value and that tank 31 is full. In this case, it is not necessary to transport the molding material from container 57 to material supply device 4, but it is desirable to transport the molding material from tank 31 to hopper 14. For this reason, in the fourth state, the control unit 5 performs the second operation described above. That is, in accordance with the second operation described above, the switching valve 58 is switched to switching position A and the blower 59 is operated. In the fourth state shown in the table in Figure 9, the second operation described above is performed, and the molding material is transported from tank 31 to hopper 14 and stored in hopper 14.

[0063] In the fifth state shown in the table of Figure 9, sensors 71 and 41a are unresponsive (OFF), and sensor 41b is responsive (ON). Therefore, the control unit 5 determines that the molding material in the hopper 14 is below the standard value, and the molding material in the tank 31 is not full but is above the lower limit. In this case, it is not necessary to transport the molding material from the container 57 to the material supply device 4, but it is desirable to transport the molding material from the tank 31 to the hopper 14. For this reason, in the fifth state, the control unit 5 performs the second operation described above. That is, in accordance with the second operation described above, the switching valve 58 is switched to switching position A, and the blower 59 is operated. In the fifth state shown in the table of Figure 9, the second operation described above is performed, and the molding material is transported from the tank 31 to the hopper 14 and stored in the hopper 14.

[0064] In the sixth state shown in the table in Figure 9, all sensors 71, 41a, and 41b are unresponsive (OFF). Therefore, the control unit 5 determines that the amount of molding material in the hopper 14 is below the standard value, and the amount of molding material in the tank 31 is below the lower limit. In this case, it is desirable to transport the molding material from the container 57 to the material supply device 4 and transport the molding material from the tank 31 to the hopper 14. However, since both cannot be done simultaneously, priority is given to transporting the molding material from the tank 31 to the hopper 14. This is because if the amount of molding material in the hopper 14 is insufficient, it may become impossible to supply a predetermined amount of molding material from the hopper 14 to the cylinder 11 in the metering process described above, potentially requiring a temporary halt to the metering process. This could lead to a decrease in the operating rate of the injection molding machine 1 and reduce the throughput in the production of molded products by the injection molding machine 1. Therefore, if the sensor 71 detects that the amount of molding material in the hopper 14 is less than the standard value, it is desirable to prioritize the second operation over the first operation. For this reason, in the sixth state, the control unit 5 performs the second operation described above. That is, in accordance with the second operation described above, the switching valve 58 is switched to switching position A, and the blower 59 is operated. In the sixth state shown in the table in Figure 9, the second operation described above is performed, and the molding material is transported from the tank 31 to the hopper 14 and stored in the hopper 14.

[0065] Furthermore, in this embodiment, since the capacity of the tank 31 is larger than the capacity of the container 57, the lower limit of the amount of molding material in the tank 31 can be set to a certain extent. By setting the lower limit of the amount of molding material in the tank 31 with sufficient margin so as not to interfere with the second operation, even if the second operation is prioritized over the first operation when the sixth state occurs, no problems (for example, the tank 31 becoming empty) will occur while the molding material is being transported from the tank 31 to the hopper 14.

[0066] Sensors 41 (specifically sensors 41a and 41b) on the material supply device 4 and sensor 71 on the hopper 14 of the injection device 2 confirm (detect) the amount of molding material in the tank 31 and the amount of molding material in the hopper 14. Depending on the result (one of the 1st to 6th states), the control unit 5 can automatically control the switching valve 58 and the blower 59. This allows the first or second operation to be performed automatically according to the amount of molding material in the tank 31 and the hopper 14, maintaining the amounts of molding material in the tank 31 and the hopper 14 at appropriate levels.

[0067] Alternatively, instead of automatic control, the first or second operation can be performed at any time by manually operating, for example, a button or keyboard. For example, after the injection molding machine 1 has finished manufacturing molded products, the first operation can be performed to fill the tank 31 with molding material in preparation for the next operation of the injection molding machine 1. Also, the first operation can be performed to fill the tank 31 with molding material during the preparation phase for starting the injection molding machine 1 to manufacture molded products.

[0068] Furthermore, in the third state described above, the amount of molding material in the hopper 14 is considered to be above the standard value, and the amount of molding material in the tank 31 is considered to be below the lower limit. Therefore, the first operation described above is performed to transport the molding material from the container 57 to the material supply device 4. In the first operation described above, the amount of molding material in the tank 31 increases each time steps S2 and S3 are repeated. For this reason, steps S2 and S3 can be repeated until the amount of molding material in the tank 31 is full, that is, until the sensor 41a reacts (turns ON). Once the sensor 41a reacts (turns ON), the first operation can be terminated. As a result, before the start of the first operation, the amount of molding material in the tank 31 was below the lower limit, but after the first operation is completed, the amount of molding material in the tank 31 is full.

[0069] However, if the sensor 41a remains unresponsive (OFF) even after repeating steps S2 and S3 a certain number of times (i.e., the amount of molding material in the tank 31 of the material supply device 4 does not become full), it is possible that the transfer of molding material from container 57 to tank 31 of material supply device 4 is not working properly. Therefore, if the first operation is started and steps S2 and S3 are repeated a predetermined number of times, but the sensor 41a remains unresponsive (OFF) (i.e., the amount of molding material in tank 31 does not become full), the control unit 5 can issue a warning (for example, by displaying a warning on the display device). In that case, the manager of the injection molding machine 1 can check the status of the transfer of molding material from container 57 to material supply device 4. For example, they can visually check the inside of container 57. Figures 10 and 11 are explanatory diagrams (cross-sectional views) showing the situation inside container 57.

[0070] Figure 5 above corresponds to the case where there is a large amount of molding material in container 57. In Figure 5, the tip of the nozzle 56 is inserted (embedded) in the molding material 30 stored in container 57, so that the molding material can be accurately sucked from the nozzle 56 in step S2 and the molding material can be accurately transported from container 57 to the hopper 34 of the material supply device 4 via the hose 51. However, as the transport of molding material from container 57 to material supply device 4 progresses, the amount of molding material in container 57 gradually decreases. Figure 10 corresponds to the case where the amount of molding material in container 57 decreases as the transport of molding material from container 57 to material supply device 4 progresses. When the amount of molding material in container 57 decreases, as shown in Figure 10, the tip of the nozzle 56 may no longer be located in the molding material 30 stored in container 57, and there is a risk that the tip of the nozzle 56 will separate from the molding material 30 in container 57. In such a situation, it becomes difficult to suck the molding material 30 from the nozzle 56 in step S2, and it becomes difficult to transport the molding material 30 from the container 57 to the hopper 34 through the hose 51. When such a situation occurs, even if steps S2 and S3 are repeated a predetermined number of times, the sensor 41a remains unresponsive (OFF), and the control unit 5 can issue a warning. In that case, the operator of the injection molding machine 1 visually checks the inside of the container 57, and if the situation shown in Figure 10 occurs, inserts the tip of the nozzle 56 into the molding material 30 stored in the container 57, as shown in Figure 11. As a result, the tip of the nozzle 56 is inserted (embedded) in the molding material 30 stored in the container 57. After that, when step S2 is restarted, the molding material can be accurately sucked from the nozzle 56, and the molding material can be accurately transported from the container 57 to the hopper 34 through the hose 51.

[0071] Furthermore, even if not in the middle of the first operation, the conditions inside the container 57 can be checked as needed, and if a situation like that shown in Figure 10 occurs, the tip of the nozzle 56 can be inserted into the molding material stored in the container 57, as shown in Figure 11.

[0072] Furthermore, in this embodiment, the hose 54 is connected to the bottom of the tank 31, and therefore the material discharge port 44 of the tank 31 to which the hose 54 is connected is also located at the bottom of the tank 31. As a result, even if the amount of molding material in the tank 31 decreases, the molding material can be accurately sucked from the material discharge port 44. Therefore, even if the amount of molding material in the tank 31 decreases, it is possible to accurately prevent malfunctions (such as failure to properly transport the molding material from the tank 31 to the hopper 14) from occurring during the second operation.

[0073] Furthermore, although this description has focused on the case where sensors 41a and 41b are provided on the material supply device 4, in other configurations, instead of sensors 41a and 41b, a position sensor capable of detecting the position of the upper surface of the molding material displaced within the tank 31 can also be provided as sensor 41. In this case, by detecting the position of the upper surface of the molding material in the tank 31 with the position sensor, the amount of molding material in the tank 31 can be determined. For example, by detecting the position of the upper surface of the molding material in the tank 31 with the position sensor, it is possible to determine whether the amount of molding material in the tank 31 is full, not full but above the lower limit, or below the lower limit. By combining this result with the detection result of sensor 71 provided on the hopper 14, it is possible to determine which of the above 1 to 6 states is present. As the position sensor, for example, a reflective type sensor can be used and can be provided on the lid 33 that constitutes the upper part of the tank 31.

[0074] Furthermore, since the capacity of tank 31 is larger than the capacity of container 57, when the first operation is performed to transport the molding material from container 57 to tank 31 of material supply device 4, all of the molding material in container 57 may be transported to tank 31 of material supply device 4, resulting in container 57 becoming empty. In that case, the nozzle 56 is removed from the empty container 57 and then inserted into another container 57 where molding material is stored. This allows the molding material to be transported from the other container 57 where molding material is stored to material supply device 4 via the nozzle 56 and hose 51.

[0075] <Regarding the background of the consideration> Figure 12 is a schematic diagram showing the general configuration of an injection molding machine 101 in an example considered by the inventors, and corresponds to Figure 1 above.

[0076] The injection molding machine 101 in the study example shown in Figure 12 does not have a material supply device 4 and a switching valve 58. In the injection molding machine 101 in the study example shown in Figure 12, the hopper 14 and blower 59 of the injection device 2 are connected via a hose 151, and the hopper 14 of the injection device 2 and a container 57 storing the molding material 30 are connected via a hose 152. A nozzle 153, such as a suction nozzle, is connected to the end of the hose 151, and the tip of the nozzle 153 is inserted into the molding material 30 in the container 57.

[0077] In the example shown in Figure 12, the supply of molding material to the hopper 14 of the injection device 2 is performed by transporting the molding material in the container 57 to the hopper 14 of the injection device 2 through the nozzle 153 and hose 152. Specifically, when the blower 59 starts blowing air, the suction force of the blower 59 is transmitted to the hose 151, hopper 14, and hose 152, so that the molding material 30 in the container 57 is sucked out through the nozzle 153 and transported to the hopper 14 of the injection device 2 through the hose 152 for storage.

[0078] However, the inventors' investigation revealed that the following problems may arise in the example shown in Figure 12.

[0079] In other words, once all the molding material in container 57 is transported to the hopper 14 of the injection molding device 2, the empty container 57 must be replaced with another container 57 containing molding material, and the nozzle 153 must be replaced in that container 57. During this container 57 replacement process, the molding material cannot be transported to the hopper 14 of the injection molding device 2. As a result, there is a risk that the molding material in the hopper 14 of the injection molding device 2 will run out during the container 57 replacement process, and if the molding material in the hopper 14 of the injection molding device 2 runs out, the injection molding machine 101 must be put into standby mode. This reduces the operating rate of the injection molding machine 101 and lowers the throughput of molded products manufactured using the injection molding machine 101.

[0080] Therefore, in order to reduce the frequency of replacing the container 57, it is conceivable to further increase the capacity of the container 57 and store a larger amount of molding material in it. However, in this case, a container 57 containing a large amount of molding material would be heavy and difficult to carry, raising concerns that it might actually reduce the efficiency of various operations. For this reason, there are limits to increasing the capacity of the container 57 and the amount of molding material stored in it. In particular, when metal chips are used as the molding material, the density of the molding material is high, making it difficult to further increase the capacity of the container 57 and store a larger amount of molding material in it.

[0081] Furthermore, in the injection molding machine 101, as the molding material is transported from the container 57 to the hopper 14 of the injection device 2 through the nozzle 153 and hose 152, the amount of molding material in the container 57 gradually decreases. When the amount of molding material in the container 57 decreases, as explained in relation to Figure 10 above, the tip of the nozzle 153 separates from the molding material 30 in the container 57, making it difficult to properly suck up the molding material from the nozzle 153. When this situation occurs, it is necessary to visually check the inside of the container 57 and insert the tip of the nozzle 153 into the molding material 30 stored in the container 57. However, while such checking and operation are being performed, the molding material cannot be transported from the container 57 to the hopper 14 of the injection device 2. This can also be a cause of reduced throughput of molded products manufactured using the injection molding machine 101.

[0082] <Main Features and Effects> One of the main features of this embodiment is the use of a material supply device 4 for supplying molding material to the hopper 14 of the injection device 2. Specifically, the tank 31 of the material supply device 4 is connected to the hopper 14 of the injection device 2 via a tubular member (in this case, a hose 54), and the material supply device 4 is also connected to a container 57 that stores molding material via a tubular member (in this case, a hose 51), enabling the transport of molding material from the container 57 to the material supply device 4 and from the tank 31 of the material supply device 4 to the hopper 14 of the injection device 2.

[0083] In this embodiment, instead of directly transporting the molding material from the container 57 storing the molding material to the hopper 14 of the injection molding machine 2, the molding material is transported from the container 57 to the material supply device 4, where it is temporarily stored in the tank 31 of the material supply device 4, and then transported from the tank 31 of the material supply device 4 to the hopper 14 of the injection molding machine 2. This allows for the transport of molding material from the tank 31 of the material supply device 4 to the hopper 14 of the injection molding machine 2 even if all the molding material in container 57 is transported to the tank 31 of the material supply device 4, and it becomes necessary to replace the empty container 57 with another container 57 containing molding material. Therefore, the tank 31 of the material supply device 4 is not empty, and the molding material can still be transported from the tank 31 of the material supply device 4 to the hopper 14 of the injection molding machine 2 during the container replacement process. As a result, even if container 57 is empty, the injection molding machine 1 does not need to be put into standby mode. Consequently, the operating efficiency of the injection molding machine 1 can be improved, and the throughput of molded products manufactured using the injection molding machine 1 can be increased.

[0084] Furthermore, as the molding material is transported from the container 57 to the material supply device 4, the amount of molding material in the container 57 gradually decreases. As explained in relation to Figure 10 above, the tip of the nozzle 56 may separate from the molding material 30 in the container 57, potentially making it difficult to effectively suck up the molding material from the nozzle 56. When this situation occurs, it is necessary to visually check the contents of the container 57 and insert the tip of the nozzle 56 into the molding material 30 stored in the container 57. However, even while performing such checks and operations, the molding material can still be transported from the tank 31 of the material supply device 4 to the hopper 14 of the injection device 2. From this perspective as well, the operating efficiency of the injection molding machine 1 can be improved, and the throughput of molded products manufactured using the injection molding machine 1 can be increased.

[0085] Furthermore, it is preferable that the capacity of the tank 31 of the material supply device 4 is larger than the capacity of the container 57. This allows a larger amount of molding material to be stored in the tank 31 of the material supply device 4 than the amount of molding material that can be stored in the container 57. As a result, the molding material can be transported from the tank 31 to the hopper 14 with a sufficient amount of molding material stored in the tank 31. This prevents the molding material in the tank 31 from becoming empty during transport from the tank 31 to the hopper 14. Consequently, the molding material can be transported from the tank 31 to the hopper 14 in the appropriate amount and at the appropriate timing. Therefore, the operating efficiency of the injection molding machine 1 can be improved, and the throughput of molded products manufactured using the injection molding machine 1 can be improved.

[0086] Furthermore, it is preferable that the tubular member (in this case, a hose 54) connecting the hopper 14 of the injection device 2 and the tank 31 of the material supply device 4 is connected to the lower part of the tank 31 of the material supply device 4. This allows the molding material in the tank 31 to be accurately drawn into the hose 54 even if the amount of molding material in the tank 31 decreases. Therefore, even if the amount of molding material in the tank 31 decreases, the molding material can be accurately transported from the tank 31 to the hopper 14.

[0087] In this embodiment, the tank 31 of the material supply device 4 is connected to the hopper 14 of the injection device 2 via a hose 54, the hopper 34 of the material supply device 4 is connected to the container 57 via a hose 51, the hopper 34 of the material supply device 4 is connected to the switching valve 58 via a hose 52, the hopper 14 of the injection device 2 is connected to the switching valve 58 via a hose 55, and the blower 59 is connected to the switching valve 58 via a hose 53. The switching valve 58 can switch between a state where hose 53 is connected to hose 52, a state where hose 53 is connected to hose 55, and a state where hose 53 is not connected to either hose 52 or 55. By controlling the switching valve 58 and the blower 59, it is possible to selectively transport the molding material from the container 57 to the material supply device 4 and transport the molding material from the tank 31 of the material supply device 4 to the hopper 14 of the injection device 2. Specifically, by operating the blower 59 when the switching valve 58 is set so that hose 53 is connected to hose 52, molding material can be transported from the container 57 to the material supply device 4. Also, by operating the blower 59 when the switching valve 58 is set so that hose 53 is connected to hose 55, molding material can be transported from the tank 31 to the hopper 14.

[0088] In this embodiment, the material supply device 4 is equipped with a sensor 41 that detects information related to the amount of molding material in the tank 31, and the hopper 14 of the injection device 2 is equipped with a sensor 71 that detects information related to the amount of molding material in the hopper 14. The control unit 5 controls the switching valve 58 and the blower 59 based on the information detected by sensors 41 and 71. This allows for the transport of molding material from the container 57 to the material supply device 4, or from the tank 31 to the hopper 14, at the appropriate timing, based on the amount of molding material in the tank 31 and the amount of molding material in the hopper 14.

[0089] (Embodiment 2) Figure 13 is a schematic diagram showing the general configuration of the injection molding machine 1 of this second embodiment, and corresponds to Figure 1 of the first embodiment described above.

[0090] The following describes the differences between the injection molding machine 1 of this second embodiment and the injection molding machine 1 of the first embodiment described above.

[0091] In Embodiment 1 described above, one blower 59 was used, but in Embodiment 2, as shown in Figure 13, two blowers 59a and 59b are used. Blower 59a is used to transport the molding material from the container 57 to the material supply device 4, and blower 59b is used to transport the molding material from the tank 31 of the material supply device 4 to the hopper 14 of the injection device 2. In addition, in Embodiment 2, the switching valve 58 is not used.

[0092] Reflecting this, in this second embodiment, one end of the hose 52 (the end opposite to the side connected to the hopper 34) is connected to the suction side of the blower 59b, rather than to the switching valve 58. Also, one end of the hose 52 (the end opposite to the side connected to the hopper 14) is connected to the suction side of the blower 59b, rather than to the switching valve 58. The control unit 5 can control the blowers 59a and 59b.

[0093] The other components of the injection molding machine 1 are substantially the same in this embodiment 2 as in the embodiment 1 described above, so a repeated explanation will be omitted here.

[0094] Furthermore, in this embodiment 2, when performing the first operation described above, step S1 in Figure 7 is not necessary, and in step S2 in Figure 7, the blowing operation of blower 59a is started instead of blower 59. Then, in step S3 in Figure 7, the blowing operation of blower 59a is stopped instead of blower 59. Also, in this embodiment 2, when performing the second operation described above, step S11 in Figure 8 is not necessary, and in step S12 in Figure 8, the blowing operation of blower 59b is started instead of blower 59. Then, in step S13 in Figure 8, the blowing operation of blower 59b is stopped instead of blower 59. Otherwise, the operation of the material supply device 4 in this embodiment 2 is almost the same as in this embodiment 1.

[0095] In this second embodiment, the tank 31 of the material supply device 4 is connected to the hopper 14 of the injection device 2 via a hose 54, the hopper 34 of the material supply device 4 is connected to the container 57 via a hose 51, the hopper 34 of the material supply device 4 is connected to the blower 59a via a hose 52, and the hopper 14 of the injection device 2 is connected to the blower 59b via a hose 55. This allows for selective transport of molding material from the container 57 to the material supply device 4 and from the tank 31 to the hopper 14 by controlling the switching valve 58 and the blowers 59a and 59b. Specifically, by operating the blower 59a, molding material can be transported from the container 57 to the material supply device 4 via the hose 51. Also, by operating the blower 59b, molding material can be transported from the tank 31 to the hopper 14 via the hose 54.

[0096] In this embodiment 2, two blowers are required, but in embodiment 1, only one blower is needed. Therefore, in embodiment 1, the number of blowers required can be reduced.

[0097] The present invention has been described in detail above based on its embodiments, but it goes without saying that the present invention is not limited to the above embodiments and can be modified in various ways without departing from its essence. [Explanation of Symbols]

[0098] 1 injection molding machine 2 Injection device 3 Mold clamping device 4 Material supply device 4 5. Control Unit 11 cylinders 12 screws 13. Drive mechanism 14 Hoppa 15 Opening 16 Heater 17 Storage section 18 nozzles 21 Fixed plate 22 Movable plate 23,24 molds 30 Molding materials 31 tanks 32 mounting bases 33 Lid 34 Hoppers 35 Filter component 36 areas 37 areas 38 Material supply port 39 Air intake 41, 41a, 41b sensors 42 Opening 43 Damper 44 Material outlet 51, 52, 53, 54, 55 Hose 56 nozzles 57 Container 58 Switching valve 59 Blower 61,62 area 63 Filter component 64 Material supply port 65 Air intake 71 CM 101 Injection molding machine 151,152 hoses 153 Nozzles

Claims

1. Injection molding machines including the following: Cylinder; A first hopper attached to the cylinder for supplying molding material into the cylinder; Screw built into the cylinder; and A material supply device for supplying the molding material to the first hopper, Here, the material supply device is A first container for storing the molding material, A second hopper is attached to the first container and is used to supply the molding material into the first container, It has, The first container of the material supply device is connected to the first hopper via a first tubular member. The second hopper of the material supply device is connected to the second container storing the molding material via a second tubular member. The material can be transported from the second container to the material supply device through the second tubular member, and the material can be transported from the first container of the material supply device to the first hopper through the first tubular member. The second hopper is connected to the switching unit via a third tubular member. The first hopper is connected to the switching unit via a fourth tubular member. The switching unit is connected to the blower via a fifth tubular member. The switching unit is capable of switching between a first connection state in which the fifth tubular member is connected to the third tubular member, a second connection state in which the fifth tubular member is connected to the fourth tubular member, and a third connection state in which the fifth tubular member is not connected to either the third or fourth tubular member. The second hopper has a first area to which the second tubular member is connected, a second area to which the third tubular member is connected, and a single first filter member disposed between the first area and the second area. The first filter member allows air to pass through, but the molding material cannot. The first hopper has a third area to which the first tubular member is connected, a fourth area to which the fourth tubular member is connected, and a single second filter member disposed between the third area and the fourth area. The second filter member allows air to pass through, but the molding material cannot.

2. In the injection molding machine according to claim 1, An injection molding machine in which the capacity of the first container is greater than the capacity of the second container.

3. In the injection molding machine according to claim 2, The first tubular member is an injection molding machine connected to the lower part of the first container.

4. In the injection molding machine according to claim 1, When the switching unit is set to the first connection state, the blower can be operated to transport the molding material in the second container to the second hopper through the second tubular member. An injection molding machine in which, when the switching unit is set to the second connection state, the blower is operated to transport the molding material in the first container to the first hopper through the first tubular member.

5. In the injection molding machine according to claim 1, The switching unit and the control unit that controls the blower, A first sensor that detects information related to the amount of molding material in the first container, A second sensor that detects information related to the amount of molding material in the first hopper, It further possesses, The control unit controls the switching unit and the blower based on the information detected by the first sensor and the second sensor in an injection molding machine.

6. In the injection molding machine according to claim 5, An injection molding machine wherein, when the control unit determines, based on the information detected by the first sensor, that the amount of molding material in the first container is less than a first reference value, it controls the switching unit and the blower to transport the molding material in the second container to the second hopper through the second tubular member.

7. In the injection molding machine according to claim 5, Injection molding machine, the control unit, based on information detected by the second sensor, determines that the amount of molding material in the first hopper is less than a second reference value, and controls the switching unit and the blower to transport the molding material in the first container to the first hopper through the first tubular member.

Images