Switching device, transportation device, and transportation method

Abstract

To provide a technique capable of cleaning a powder-granular material remaining on a transport route, when transporting the powder-granular material from one selected from among a plurality of transport sources to a transport destination.SOLUTION: In a transport device 1 for transporting a powder-granular material to a transport destination by passing through an inside of a pipeline unit 30 from a selected transport source by an air flow, a transport switching device switches a direction of the air flow inside the pipeline unit 30. The piping unit 30 comprises: material inflow pipelines 31a to 31e whose upstream ends are connected to respective transportation sources; air inflow pipelines 35a to 35e whose upstream ends are openable to outside air; a common pipe 34 whose downstream end is connected to the transport destination; discharge pipelines 33a to 33e whose downstream ends are connected to the common pipe 34; switching valves 32a to 32e for switching communication between the downstream ends of the material inflow pipelines 31a to 31e and the upstream ends of the discharge pipelines 33a to 33e, to which the air inflow pipelines 35a to 35e are connected; and a first outside air introduction valve 36 including valves 37a to 37e opening / closing the upstream ends of the air inflow pipelines 35a to 35e with respect to the outside air.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a transport device that transports powder or granular material (hereinafter referred to as "powder or granular material") by airflow from one selected from one or more transport sources through a piping unit to a destination, a transport method using the transport device, and a switching device that switches the direction of the airflow within the piping unit. [Background technology]

[0002] In a conventional manufacturing process for plastic products, powder or granular material is transported from one of a plurality of raw material tanks storing various raw materials to a destination such as an injection molding machine by airflow in a pipe while changing the direction of the airflow. Such an apparatus for transporting powder or granular material from a plurality of sources to a destination is disclosed, for example, in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-112527 Summary of the Invention [Problem to be solved by the invention]

[0004] The raw material measuring device (1) of Patent Document 1 includes a raw material switching unit (3) and a measuring unit (2). The raw material switching unit (3) includes a casing (19), four raw material supply pipes (33), and four pneumatic transport on-off valves (25) (see paragraph 0015, Figures 4 and 7). The downstream end of the raw material supply pipe (33) opens into the casing (19) as a supply port (78). The upstream end of the raw material supply pipe (33) is connected to four raw material tanks storing raw materials composed of different types of powder and granular material (see paragraph 0016). The pneumatic transport on-off valves (25) face the supply port (78) from the opposite direction. The pneumatic transport on-off valve (25) includes a piston (9) and a valve element (6). The piston (9) moves back and forth to bring the valve element (9) into contact with and away from the supply port (78), thereby opening and closing the supply port (78). The raw material switching unit (3) selectively switches the raw material to be supplied by opening one of the four supply ports (78) and closing the others (paragraph 0017). A weighing hopper (38) is disposed below the weighing unit (2), and a suction blower is connected to the weighing hopper (38). When the suction blower is driven, the raw material selectively supplied by the raw material switching unit (3) is pneumatically transported to the weighing hopper (38) (paragraph 0019).

[0005] However, when the raw materials are pneumatically transported, the raw materials may not reach the weighing hopper 38, which is the destination, and may remain in the casing 19 of the raw material switching unit 3. In this case, if the raw material tank is subsequently changed and a different type of raw material is transported, the remaining raw material may be mixed in, which may result in a deterioration in product quality.

[0006] The present invention aims to provide an apparatus and method that can transport powdered or granular material by airflow from one selected from one or more transport sources through a piping unit to a destination while cleaning any powdered or granular material remaining on the transport route. [Means for solving the problem]

[0007] To solve the above problems, the first invention of the present application relates to a transport device that transports powder or granular material by airflow from one selected from one or more transport sources through a piping unit to a transport destination, and a switching device that switches the direction of the airflow within the piping unit. The piping unit includes one or more material inlet pipes, each connected at its upstream end to the one or more transport sources, one or more air inlet pipes, each open at its upstream end to outside air, a common pipe, connected at its downstream end to the transport destination, one or more discharge pipes, each connected at its downstream end to the common pipe, one or more switching valves, each connected to the downstream end of one of the air inlet pipes and switching communication between the downstream end of the one or more material inlet pipes and the upstream end of one of the one or more discharge pipes, and a first outside air introduction valve, each provided on one of the air inlet pipes and including one or more valves (solenoid valves), that opens and closes the upstream end of each of the air inlet pipes to outside air.

[0008] The second invention of the present application is a switching device of the first invention, wherein the one or more switching valves each switch communication between the downstream end of one of the one or more material inlet pipes and the upstream end of one of the one or more outlet pipes.

[0009] The third invention of the present application is a transportation device having a switching device of the first or second invention, the one or more transport sources, the transport destination, and an airflow generating means within the piping unit that generates an airflow from the selected one transport source to the transport destination.

[0010] A fourth invention of the present application is a transportation device of the third invention, wherein the airflow generating means generates an airflow within the piping unit from the selected one transport source to the transport destination by sucking air from the transport destination.

[0011] A fifth invention of the present application is a transport device according to the third or fourth invention, wherein each of the one or more switching valves comprises a casing provided with a material inlet to which the downstream end of the material inlet pipe is connected, an air inlet to which the downstream end of the air inlet pipe is connected, and an outlet to which the upstream end of the discharge pipe is connected, a valve element for opening and closing the material inlet, and a drive mechanism for moving the valve element back and forth in a direction perpendicular to the material inlet, wherein when the valve element is driven by the drive mechanism to open the material inlet, powder or granular material flows into the casing and flows out through the outlet, and when the valve element is driven by the drive mechanism to close the material inlet, the flow of powder or granular material into the casing is stopped.

[0012] A sixth invention of the present application is a transportation device according to the fifth invention, further comprising a control unit electrically connected to the first outside air introduction valve and controlling the opening and closing of each of the one or more valves, wherein the control unit issues an open command to the first outside air introduction valve for a specific valve, and when the specific valve is opened, outside air flows into the casing through the air inlet pipe and the air inlet in which the specific valve is provided and flows out through the outlet, and when the control unit issues a close command to the first outside air introduction valve for the specific valve and closes the specific valve, the flow of outside air into the casing through the air inlet pipe and the air inlet in which the specific valve is provided is stopped.

[0013] The seventh invention of the present application is a transportation device according to any one of the third to sixth inventions, wherein the piping unit further has a second outside air introduction valve provided at the upstream end of the common pipe and opening and closing the upstream end of the common pipe to the outside air.

[0014] The eighth invention of the present application is a transportation device according to any one of the third to seventh inventions, wherein each of the one or more discharge pipes is inclined downward from horizontal as it approaches the downstream end where it is connected to the common pipe.

[0015] A ninth aspect of the present invention is the transportation device of any one of the third to eighth aspects, further comprising a support member to which the one or more switching valves are fixed.

[0016] A tenth invention of the present application is a transport device comprising the switching device of the first invention, a plurality of transport sources, the transport destinations, and an airflow generating means within the piping unit for generating an airflow from the selected one of the transport sources to the transport destination, wherein the piping unit has a plurality of the material inlet pipes, each of whose upstream ends is connected to the plurality of transport sources, and each of the one or more switching valves switches communication between the respective downstream ends of the plurality of material inlet pipes and the upstream end of one of the one or more discharge pipes.

[0017] The eleventh invention of the present application relates to a transportation method for transporting powder or granular material by airflow from one selected from one or more transport sources through a piping unit to a destination, and switching the direction of the airflow within the piping unit. The piping unit includes one or more material inlet pipes, each connected at its upstream end to the one or more transport sources, one or more air inlet pipes, each open at its upstream end to outside air, a common pipe, connected at its downstream end to the destination, one or more discharge pipes, each connected at its downstream end to the common pipe, one or more switching valves, each connected to the downstream end of one of the air inlet pipes and switching communication between the downstream end of the one or more material inlet pipes and the upstream end of one of the one or more discharge pipes, and a first outside air introduction valve, each including one or more valves, provided in each of the one or more air inlet pipes and opening and closing the upstream end of each of the one or more air inlet pipes to outside air. Each of the one or more switching valves has a casing provided with a material inlet to which the downstream end of the material inlet pipe is connected, an air inlet to which the downstream end of the air inlet pipe is connected, and an outlet to which the upstream end of the discharge pipe is connected, a valve body that opens and closes the material inlet, and a drive mechanism that moves the valve body back and forth in a direction perpendicular to the material inlet. The transportation method also includes the steps of: a) driving the drive mechanism to open the material inlet at a specific switching valve located on a route from the selected one of the transport sources to the transport destination, thereby connecting the material inlet piping connected to the selected one of the transport sources with the discharge piping, and sucking air from the transport destination, thereby transporting powder or granular material from the selected one of the transport sources to the transport destination; and b) after step a), while air has been sucked from the transport destination, issuing an open command for the valve provided in the air inlet piping connected to the specific switching valve, and opening the valve, thereby allowing outside air to flow into the casing via the air inlet piping and the air inlet.

[0018] A twelfth invention of the present application is the transportation method of the eleventh invention, further comprising the step of: c) after step a), blocking the material inlet of the specific switching valve by driving the drive mechanism, thereby cutting off communication between the material inlet pipe and the discharge pipe connected to the selected one transportation source.

[0019] A thirteenth aspect of the present invention is a transportation method according to the eleventh or twelfth aspect of the present invention, further comprising the step of: d) after continuing step b) for a predetermined time, issuing a closing command to the valve provided in the air inlet pipe connected to the specific switching valve, and closing the valve to stop the inflow of outside air into the casing via the air inlet pipe and the air inlet, thereby carrying out a cleaning step consisting of steps b) and d) via the specific switching valve.

[0020] The 14th invention of the present application is a transportation method according to the 13th invention, in which e) after step d), the cleaning steps are carried out in sequence via other switching valves other than the specific switching valve among the one or more switching valves in the piping unit.

[0021] A 15th invention of the present application is a transportation method according to the 13th or 14th invention, wherein the piping unit further has a second outside air introduction valve provided at the upstream end of the common pipe, which opens and closes the upstream end of the common pipe to outside air, and further includes a step of: f) after step d), opening the second outside air introduction valve while air is being sucked in from the destination of transportation, thereby allowing outside air to flow into the common pipe from the upstream end of the common pipe.

[0022] The 16th invention of the present application is a transportation method according to any one of the 13th to 15th inventions, wherein h) if a transportation source other than the selected one is selected from the one or more transportation sources, the cleaning process is again performed in sequence, passing through all of the one or more switching valves in the piping unit, while air is again sucked from the destination. [Effects of the Invention]

[0023] According to the first to sixteenth inventions of the present application, by connecting the material inlet pipe and the outlet pipe using a switching valve, the powder or granular material can be transported by airflow from one selected from one or more sources through the piping unit to the destination, and then the direction of the airflow within the piping unit can be switched using the first outside air introduction valve, so that the powder or granular material still remaining in the piping unit can be transported to the destination.

[0024] In particular, according to the fourth aspect of the present invention, it is possible to generate an airflow from one selected transport source to a transport destination with a simple configuration.

[0025] In particular, according to the fifth and eleventh aspects of the present invention, the switching valve can be configured with a simple structure and at low cost.

[0026] In particular, according to the seventh and fifteenth inventions of the present application, by opening the second outside air intake valve and taking in outside air from the upstream end of the common pipe, powder or granular material still remaining in the common pipe can be transported to its destination.

[0027] In particular, according to the eighth aspect of the present invention, the powder or granular material can be prevented from remaining in the discharge pipe, and can be transported to the destination more smoothly.

[0028] In particular, according to the fourteenth aspect of the present invention, powder or granular material remaining in the piping unit between other switching valves and just before the destination can be transported to the destination in order of priority.

[0029] In particular, according to the 16th invention of the present application, when the source of the powdered or granular material is changed, the powdered or granular material still remaining in the piping unit from all switching valves to just before the destination is transported to the destination again, thereby preventing the newly transported powdered or granular material from mixing with the remaining powdered or granular material. [Brief explanation of the drawings]

[0030] [Figure 1]FIG. 1 is a diagram conceptually illustrating the configuration of a transportation device. [Figure 2] FIG. [Figure 3] FIG. 2 is a block diagram showing connections between a control unit and each unit. [Figure 4] 10 is a flowchart showing the flow of a powder / granular material transport process and a piping unit cleaning process. DETAILED DESCRIPTION OF THE INVENTION

[0031] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0032] <1. Transport device configuration> 1 is a diagram conceptually illustrating the configuration of a transport device 1 according to one embodiment of the present invention. This transport device 1 is a device that transports powder or granular material, including, for example, resin pellets that are raw materials for resin molded products such as plastics, from a source to a destination. In particular, the transport device 1 of this embodiment transports powder or granular material by airflow from one selected from one or more sources to a destination in a plastic product manufacturing process.

[0033] As shown in FIG. 1, the transport device 1 of this embodiment has five first hoppers 10a, 10b, 10c, 10d, and 10e, which are the transport source, a second hopper 20, which is the transport destination, a piping unit 30, an exhaust pipe 40, a blower 50, and a control unit 60. Of the five first hoppers 10a to 10e, the first hoppers 10b to 10e and their peripheral components are not shown in FIG. 1. However, the number of first hoppers included in the transport device 1 may be one to four, or may be six or more. In other words, the transport device 1 may have one or more first hoppers.

[0034] Each of the first hoppers 10a to 10e is a container that stores powdered or granular material before transportation. The first hoppers 10a to 10e are an example of a transportation source in the present invention. In this embodiment, different types of powdered or granular material are stored in the five first hoppers 10a to 10e. For example, the first hopper 10a stores resin pellets, which are the main raw material of resin molded products, the first hoppers 10b to 10d store powdered or granular material such as master batches and additives used as colorants for coloring resin molded products, and the first hopper 10e stores crushed recycled material. However, the types of powdered or granular material stored in the first hoppers 10a to 10e are not limited to these.

[0035] In this embodiment, the five first hoppers 10a to 10e have the same structure. Each of the first hoppers 10a to 10e has a substantially cylindrical sidewall 11, a funnel-shaped bottom 12 that gradually converges downward from the lower end of the sidewall 11, and a top plate 13 that covers the upper portion. A space for storing powdered or granular material is provided inside the first hoppers 10a to 10e. A first discharge port 14 is provided at the center of each bottom 12 for discharging powdered or granular material from the first hoppers 10a to 10e to the piping unit 30. The first discharge port 14 is an example of a connection port in the present invention. The first hoppers 10a to 10e may have other shapes. For example, the sidewall 11 may be a rectangular cylindrical shape. The multiple first hoppers included in the transport device 1 may have different structures.

[0036] Further, an on-off valve 16 and an on-off mechanism 17 connected to the on-off valve 16 are attached to each first discharge port 14. The on-off mechanism 17 opens and closes the on-off valve 16 by, for example, operating an air cylinder in response to a command from the control unit 60 to move a valve element back and forth. However, instead of the on-off valve 16 and the on-off mechanism 17, a manual valve that can be opened and closed manually may be attached to each first discharge port 14.

[0037] Above each of the first hoppers 10a to 10e, there is disposed a device (upstream device) that supplies powdered or granular material to the first hoppers 10a to 10e. Each upstream device supplies a predetermined type of powdered or granular material to the first hoppers 10a to 10e. Therefore, the types of powdered or granular material supplied from the upstream device above each of the first hoppers 10a to 10e are different from each other. However, each upstream device may measure multiple types of powdered or granular material to a predetermined mixing ratio and supply them to the first hoppers 10a to 10e. Furthermore, the first hoppers 10a to 10e do not necessarily have to be connected to an upstream device. For example, an operator may manually add powdered or granular material to the first hoppers 10a to 10e.

[0038] The second hopper 20 is a container for temporarily storing powdered or granular material transported from the first hoppers 10a to 10e via the piping unit 30. The second hopper 20 is an example of a transport destination in the present invention. The second hopper 20 has a substantially cylindrical side wall 21, a funnel-shaped bottom 22 that gradually converges downward from the lower end of the side wall 21, and a top plate 23 that covers the upper part. A space for temporarily storing powdered or granular material is provided inside the second hopper 20. The second hopper 20 may have another shape. For example, the side wall 21 may be a rectangular cylinder.

[0039] The side walls 21 are provided with an inlet 24 for receiving powdered or granular material. A second outlet 25 for discharging powdered or granular material from the second hopper 20 is provided in the center of each bottom portion 22. The top plate portion 23 is provided with an exhaust port 26 for sucking air out of the second hopper 20.

[0040] Further, a discharge valve 27 that controls the opening and closing of the second discharge port 25 is attached to the second discharge port 25. The discharge valve 27 may, for example, be a mechanism that operates an air cylinder to move a valve element back and forth in response to a command from the control unit 60. However, instead of the discharge valve 27, a manual valve that can be opened and closed manually may be attached to the second discharge port 25. Further, below the second hopper 20, a device (downstream device 29) that receives the powdered or granular material discharged from the second discharge port 25 is disposed. The downstream device 29 is, for example, an injection molding machine. When the second discharge port 25 is opened, the powdered or granular material in the second hopper 20 is discharged through the second discharge port 25 to the downstream device 29.

[0041] The piping unit 30 constitutes a transport path connecting the first hoppers 10a to 10e and the second hopper 20. As shown in Fig. 1, the piping unit 30 of this embodiment has five material inlet pipes 31a, 31b, 31c, 31d, and 31e, five switching valves 32a, 32b, 32c, 32d, and 32e, five discharge pipes 33a, 33b, 33c, 33d, and 33e, one common pipe 34, five air inlet pipes 35a, 35b, 35c, 35d, and 35e, one first outside air introduction valve 36, one second outside air introduction valve 341, and five third outside air introduction valves 311.

[0042] However, the number of material inlet pipes 31a-31e, switching valves 32a-32e, discharge pipes 33a-33e, air inlet pipes 35a-35e, and third outside air introduction valves 311 included in the piping unit 30 may be 1 to 4, or 6 or more, as long as the number is the same as the number of first hoppers 10a-10e. That is, the piping unit 30 only needs to have one or more material inlet pipes, one or more switching valves, one or more discharge pipes, one common pipe, one or more air inlet pipes, one first outside air introduction valve, one second outside air introduction valve, and one or more third outside air introduction valves.

[0043] The material inlet pipes 31a to 31e are each composed of a metal circular pipe. The upstream ends of the material inlet pipes 31a to 31e are connected to the first hoppers 10a to 10e via the first discharge outlets 14, which are connection ports. Specifically, the upstream end of the material inlet pipe 31a is connected to the first discharge outlet 14 of the first hopper 10a. The upstream end of the material inlet pipe 31b is connected to the first discharge outlet 14 of the first hopper 10b. The upstream end of the material inlet pipe 31c is connected to the first discharge outlet 14 of the first hopper 10c. The upstream end of the material inlet pipe 31d is connected to the first discharge outlet 14 of the first hopper 10d. The upstream end of the material inlet pipe 31e is connected to the first discharge outlet 14 of the first hopper 10e.

[0044] Each of the material inlet pipes 31a to 31e has an opening 310 near the first exhaust port 14. A third outside air introduction valve 311, an opening / closing mechanism 312 connected to the third outside air introduction valve 311, and a filter 313 are attached to each opening 310. The opening / closing mechanism 312 opens and closes the third outside air introduction valve 311 by, for example, operating an air cylinder in response to a command from the control unit 60 to move the valve element back and forth. By opening and closing the third outside air introduction valve 311, the opening 310 can be opened and closed to outside air. Opening the third outside air introduction valve 311 also allows outside air to be taken into the material inlet pipes 31a to 31e through the filter 313. Instead of the third outside air introduction valve 311 and the opening / closing mechanism 312, a manual valve that can be opened and closed manually may be attached.

[0045] Each of the switching valves 32a to 32e is a mechanism for switching communication between the downstream end of one of the material inlet pipes 31a to 31e and the upstream end of one of the outlet pipes 33a to 33e. Specifically, the switching valve 32a switches communication between the material inlet pipe 31a and the outlet pipe 33a. The switching valve 32b switches communication between the material inlet pipe 31b and the outlet pipe 33b. The switching valve 32c switches communication between the material inlet pipe 31c and the outlet pipe 33c. The switching valve 32d switches communication between the material inlet pipe 31d and the outlet pipe 33d. The switching valve 32e switches communication between the material inlet pipe 31e and the outlet pipe 33e.

[0046] Furthermore, the downstream end of one of the air inlet pipes 35a to 35e is connected to each of the switching valves 32a to 32e. Specifically, the downstream end of the air inlet pipe 35a is connected to the switching valve 32a. The downstream end of the air inlet pipe 35b is connected to the switching valve 32b. The downstream end of the air inlet pipe 35c is connected to the switching valve 32c. The downstream end of the air inlet pipe 35d is connected to the switching valve 32d. The downstream end of the air inlet pipe 35e is connected to the switching valve 32e.

[0047] 2 is a vertical cross-sectional view of each of the switching valves 32a to 32e. As shown in FIG. 2, each of the switching valves 32a to 32e includes a casing 321, a valve element 322, and a drive mechanism 323.

[0048] The casing 321 is a hollow metal frame. A circular material inlet 710 is provided at the upstream end 71 of the casing 321. The material inlet 710 connects the interior space of the casing 321 with the exterior space. The downstream end of one of the material inlet pipes 31a to 31e is connected to the material inlet 710 by being fitted and fixed. Specifically, the downstream end of the material inlet pipe 31a is connected to the material inlet 710 of the switching valve 32a. The downstream end of the material inlet pipe 31b is connected to the material inlet 710 of the switching valve 32b. The downstream end of the material inlet pipe 31c is connected to the material inlet 710 of the switching valve 32c. The downstream end of the material inlet pipe 31d is connected to the material inlet 710 of the switching valve 32d. The downstream end of the material inlet pipe 31e is connected to the material inlet 710 of the switching valve 32e. However, the downstream end of one of the material inlet pipes 31a to 31e may be indirectly connected to the material inlet 710 via a separately prepared pipe.

[0049] 2, the downstream ends of the material inlet pipes 31a to 31e slightly protrude into the internal space of the casing 321. This prevents the powder from getting caught and staying near the material inlet port 710 when the powder flows from the internal space of each of the material inlet pipes 31a to 31e into the internal space of the casing 321, as will be described later. However, the downstream ends of the material inlet pipes 31a to 31e do not have to protrude into the internal space of the casing 321.

[0050] A circular outlet 720 is provided at the downstream end 72 of the casing 321. The outlet 720 connects the internal space of the casing 321 with the external space. The upstream end of one of the discharge pipes 33a to 33e is connected to the outlet 720 by being fitted and fixed. Specifically, the upstream end of the discharge pipe 33a is connected to the outlet 720 of the switching valve 32a. The upstream end of the discharge pipe 33b is connected to the outlet 720 of the switching valve 32b. The upstream end of the discharge pipe 33c is connected to the outlet 720 of the switching valve 32c. The upstream end of the discharge pipe 33d is connected to the outlet 720 of the switching valve 32d. The upstream end of the discharge pipe 33e is connected to the outlet 720 of the switching valve 32e.

[0051] A circular air inlet 730 is provided in the side portion 73 of the casing 321. The air inlet 730 communicates the internal space with the external space of the casing 321. As described above, the downstream end of one of the air inlet pipes 35a to 35e is connected to the air inlet 730 by being fitted and fixed thereto.

[0052] The valve element 322 is a metal member that opens and closes the material inlet 710. The valve element 322 includes a planar contact surface 81. The contact surface 81 is substantially parallel to the material inlet 710, and the outer diameter of the contact surface 81 is larger than the outer diameter of the material inlet 710. As a result, the material inlet 710 is opened and closed by the contact surface 81 coming into contact with or separating from the downstream ends of the material inlet pipes 31a to 31e fixed to the material inlet 710. As described above, the valve element 322 in this embodiment is made of metal. Therefore, even if the valve element 322 comes into pressure contact with the material inlet pipes 31a to 31e or the powder or granular material, damage and wear of the valve element 322 are suppressed. However, the valve element 322 may be made of resin.

[0053] The drive mechanism 323 is a device that moves the valve disc 322 back and forth in a direction perpendicular to the material inlet 710. The drive mechanism 323 reciprocates the valve disc 322 in the direction of a valve disc axis 810 that passes through the center of the material inlet 710 and is perpendicular to the material inlet 710. The drive mechanism 323 has a main body 82, a displacement rod 83, and a support mechanism 84. The drive mechanism 323 generates power to displace the displacement rod 83 along the valve disc axis 810 by supplying air to and discharging air from a push-side internal space 821 located on the push side of the displacement rod 83 within the internal space of the main body 82, and supplying air to and discharging air from a pull-side internal space 822 located on the pull side of the displacement rod 83 within the internal space of the main body 82.

[0054] The main body 82 is fixed to the casing 321 by a support mechanism 84 including a bolt and nut structure. A valve element 322 is attached to the tip of the displacement rod 83. In response to commands from the control unit 60, the drive mechanism 323 supplies air to the push-side internal space 821 and exhausts air from the push-side internal space 821, and supplies air to the pull-side internal space 822 and exhausts air from the pull-side internal space 822, thereby displacing the displacement rod 83 and moving the valve element 322 back and forth along the direction of the valve element axis 810.

[0055] The valve element 322 faces the material inlet 710 in the direction of the valve element axis 810. As described above, the contact surface 81 is substantially parallel to the material inlet 710, and the outer diameter of the contact surface 81 is larger than the outer diameter of the material inlet 710. As a result, when the valve element 322 is moved toward the material inlet 710 by the drive mechanism 323 and the contact surface 81 comes into contact with the downstream end of the material inlet piping 31a-31e, the material inlet 710 is closed. As a result, even if an airflow is generated in the piping unit 30 from a selected one of the first hoppers 10a-10e, which is the transport source, to the second hopper 20, which is the transport destination, by the drive of the blower 50 (described later), the airflow does not pass through the material inlet 710, and the inflow of powder and granular material into the casing 321 through the material inlet 710 is stopped.

[0056] On the other hand, when the valve element 322 is retracted from the material inlet 710 by the drive mechanism 323 and the contact surface 81 moves away from the downstream end of the material inlet pipes 31a-31e, the material inlet 710 is opened. As a result, when the blower 50, which will be described later, is driven to generate an airflow within the piping unit 30 from a selected one of the first hoppers 10a-10e, which is the transport source, to the second hopper 20, which is the transport destination, the powder or granular material flows into the casing 321 through the material inlet 710 and flows out through the outlet 720. In this embodiment, the changeover valves 32a-32e can be configured at low cost with such a simple structure.

[0057] The discharge pipes 33a to 33e are each formed of a metal circular pipe. As described above, the upstream ends of the discharge pipes 33a to 33e are connected to the outlets 720 of the switching valves 32a to 32e. Specifically, the upstream end of the discharge pipe 33a is connected to the outlet 720 of the switching valve 32a. The upstream end of the discharge pipe 33b is connected to the outlet 720 of the switching valve 32b. The upstream end of the discharge pipe 33c is connected to the outlet 720 of the switching valve 32c. The upstream end of the discharge pipe 33d is connected to the outlet 720 of the switching valve 32d. The upstream end of the discharge pipe 33e is connected to the outlet 720 of the switching valve 32e. Furthermore, the downstream ends of the discharge pipes 33a to 33e are each connected to the common pipe 34.

[0058] The transport device 1 of this embodiment is also provided with a metal support member (not shown). The switching valves 32a-32e are supported by the support member, for example, by being fixed close to each other. With the switching valves 32a-32e supported by the support member, the discharge pipes 33a-33e are each inclined downward from the horizontal toward the downstream end connected to the common pipe 34 (described later). As a result, when an airflow is generated in the piping unit 30 by driving the blower 50 (described later) from a selected one of the first hoppers 10a-10e, which is the transport source, toward the second hopper 20, which is the transport destination, the powder or granular material can be transported more smoothly to the destination while being prevented from remaining in the discharge pipes 33a-33e.

[0059] The common pipe 34 is made of a metal circular pipe. The downstream end of the common pipe 34 is connected to the inlet 24 of the second hopper 20. As shown in FIG. 1 , a second outside air introduction valve 341, an opening / closing mechanism 342 connected to the second outside air introduction valve 341, and a filter 343 are attached to an opening 340 at the upstream end of the common pipe 34 as viewed in the powder / granular material transport direction td. The opening / closing mechanism 342 opens and closes the second outside air introduction valve 341 by, for example, operating an air cylinder in response to a command from the control unit 60 to move the valve element back and forth. By opening and closing the second outside air introduction valve 341, the opening 340 at the upstream end of the common pipe 34 can be opened and closed to outside air. Furthermore, by opening the second outside air introduction valve 341, outside air can be taken into the common pipe 34 from the opening 340 at the upstream end of the common pipe 34 via the filter 343. However, instead of the second outside air introduction valve 341 and the opening / closing mechanism 342, a manual valve that can be opened and closed manually may be installed.

[0060] The air inlet pipes 35a to 35e are each formed of a metal circular pipe. As described above, the downstream ends of the air inlet pipes 35a to 35e are connected to the air inlets 730 of the switching valves 32a to 32e. In this embodiment, the upstream ends of the air inlet pipes 35a to 35e are shared as a single metal circular pipe, the common air pipe 361. That is, the upstream ends of the air inlet pipes 35a to 35e are the upstream end of the single common air pipe 361. An opening 360 at the upstream end of each of the air inlet pipes 35a to 35e, i.e., the opening 360 at the upstream end of the common air pipe 361, is open to the outside air. A filter 362 is attached to the opening 360.

[0061] Each of the air inlet pipes 35a to 35e is equipped with a first outside air introduction valve 36. The first outside air introduction valve 36 includes five valves (solenoid valves) 37a, 37b, 37c, 37d, and 37e and an opening / closing mechanism 38. The valve 37a is provided in the air inlet pipe 35a. The valve 37b is provided in the air inlet pipe 35b. The valve 37c is provided in the air inlet pipe 35c. The valve 37d is provided in the air inlet pipe 35d. The valve 37e is provided in the air inlet pipe 35e.

[0062] However, the number of valves 37a-37e included in the first outside air introduction valve 36 may be 1 to 4, or may be 6 or more, as long as it is the same as the number of switching valves 32a-32e and air inlet pipes 35a-35e. In other words, the first outside air introduction valve may be made up of one or more valves, and the one or more valves may be provided in each of the one or more air inlet pipes.

[0063] In response to commands from the control unit 60, the opening / closing mechanism 38 energizes or de-energizes the solenoids, thereby reciprocating the valve elements and opening or closing the valves 37a-37e. Opening the valves 37a-37e opens the upstream ends of the air inlet pipes 35a-35e to the outside air, allowing outside air to be taken in through the opening 360 and the filter 362. This allows outside air to flow into the casing 321 via the air inlet pipes 35a-35e and the air inlets 730 of the switching valves 32a-32e and to flow out through the outlet 720. Closing the valves 37a-37e, on the other hand, closes the upstream ends of the air inlet pipes 35a-35e to the outside air, preventing outside air from being taken in through the opening 360. This prevents outside air from flowing into the casing 321 via the air inlet pipes 35a-35e and the air inlets 730 of the switching valves 32a-32e.

[0064] More specifically, when the control unit 60 issues a command to the first outside air introduction valve 36 to open, for example, the valve 37a as a specific valve, the opening / closing mechanism 38 opens the specific valve 37a. As a result, outside air flows into the casing 321 via the filter 362, the air inlet pipe 35a in which the specific valve 37a is provided, and the air inlet 730 of the switching valve 32a to which the air inlet pipe 35a is connected, and then flows out through the outlet 720. On the other hand, when the control unit 60 issues a command to the first outside air introduction valve 36 to close, for example, the valve 37a as a specific valve, the opening / closing mechanism 38 closes the specific valve 37a. As a result, the flow of outside air into the casing 321 via the air inlet pipe 35a in which the specific valve 37a is provided and the air inlet 730 of the switching valve 32a to which the air inlet pipe 35a is connected is stopped.

[0065] The exhaust pipe 40 is a pipe for sucking air out of the second hopper 20. The upstream end of the exhaust pipe 40 is connected to the exhaust port 26 of the second hopper 20. The downstream end of the exhaust pipe 40 is connected to a blower 50.

[0066] The blower 50 is a mechanism that generates an airflow for sucking and transporting powder and granular material. The blower 50 is an example of the airflow generating means of the present invention. The blower 50 generates an airflow in the exhaust pipe 40 by rotating an impeller in response to a drive signal input from the control unit 60.

[0067] When the blower 50 connected to the second hopper 20 via the exhaust pipe 40 is driven, the air inside the second hopper 20 is sucked into the exhaust pipe 40 and discharged to the outside through the blower 50. As a result, the air pressure inside the second hopper 20 becomes a negative pressure lower than the outside air pressure. As a result, outside air is taken into the piping unit 30 from the opening 310 of the material inlet pipe (one of the material inlet pipes 31a-31e) connected to the first discharge outlet 14 of the selected one of the first hoppers 10a-10e, which is the transport source. As a result, an airflow is generated inside the piping unit 30, flowing from the selected one of the first hoppers 10a-10e, which is the transport source, to the second hopper 20, which is the transport destination.

[0068] In this embodiment, with such a simple structure, it is possible to generate an airflow that flows from a selected one of the first hoppers 10a to 10e, which is the transport source, to the second hopper 20, which is the transport destination. A filter 28 is provided at the exhaust port 26 of the second hopper 20. The filter 28 prevents the powder or granular material from flowing into the exhaust pipe 40 while allowing air to pass through. The filter 28 is, for example, a punched metal plate having a plurality of through holes that are smaller than the powder or granular material.

[0069] In this embodiment, first, one of the first hoppers 10a-10e is selected as the transport source of the powder or granular material. Furthermore, in a specific switching valve (one of the switching valves 32a-32e) located on the path from the selected source to the destination, the drive mechanism 323 is driven to open the material inlet 710. This allows communication between the material inlet pipe (one of the material inlet pipes 31a-31e) connected to the selected source and the discharge pipe (one of the discharge pipes 33a-33e). Meanwhile, in the other switching valves not on the path from the selected source to the destination, the drive mechanism 323 is driven to close the material inlet 710.

[0070] Furthermore, a valve (one of valves 37a to 37e) provided in an air inlet pipe (one of air inlet pipes 35a to 35e) connected to the specific switching valve (one of switching valves 32a to 32e) is opened or closed. This forms a switching device in this embodiment that switches the direction of airflow in the piping unit 30 connecting the selected one transport source and transport destination. Meanwhile, the valves provided in the air inlet pipes connected to the other switching valves remain closed.

[0071] The control unit 60 is a control means that controls the operation of each part of the transportation device 1. In addition, the control unit 60 of this embodiment is electrically connected to the opening / closing mechanism 38 of the first outside air introduction valve 36, and controls the opening and closing of each of the valves 37a to 37e. Figure 3 is a block diagram showing the connection between the control unit 60 and each part in the transportation device 1. 3, the control unit 60 is electrically connected to the on-off mechanism 17 connected to the on-off valve 16 attached to each of the first discharge ports 14 of the first hoppers 10a-10e, the on-off mechanism 342 connected to the second outside air introduction valve 341 attached to the opening 340 of the common pipe 34, the on-off mechanism 312 connected to the third outside air introduction valve 311 attached to the opening 310 of the material inlet pipe 31a-31e, the drive mechanism 323 of each of the switching valves 32a-32e, the on-off mechanism 38 that opens and closes the valves 37a-37e of the first outside air introduction valve 36, the discharge valve 27 attached to the second discharge port 25 of the second hopper 20, and the blower 50. The control unit 60 is configured by a computer having a calculation processing unit 601 such as a CPU, a memory 602, and a storage device 603.

[0072] The control unit 60 controls the operation of each of the above-mentioned units based on a preset operation sequence S and parameters P stored in the storage device 603, and on external input signals. This allows the powder transport process and the cleaning process (described later) in the transport device 1 to proceed. However, the on-off valve 16, the second outside air introduction valve 341, the third outside air introduction valve 311, the switching valves 32a to 32e, the discharge valve 27, and the blower 50 may be separated from the control unit 60 and operated manually by an operator.

[0073] <2. Transportation method> Next, a description will be given of a powder or granular material transport method using the above-described transport device 1. Fig. 4 is a flowchart showing the flow of a powder or granular material transport step and a piping unit 30 cleaning step.

[0074] As described above, in the transport process using the transport device 1 of this embodiment, powdered or granular material is transported by airflow from one selected from one or more transport sources to a destination through the piping unit 30. Specifically, first, one of the first hoppers 10a to 10e is selected as the transport source of the powdered or granular material. Below, as an example, a case where the first hopper 10a is selected as the transport source from among the first hoppers 10a to 10e will be described.

[0075] When starting the transport of powdered or granular material, first, the control unit 60 sends a drive signal to the opening / closing mechanism 17 attached to the first discharge outlet 14 of the first hopper 10a, which is the selected transport source, to open the opening / closing valve 16. The control unit 60 also sends a drive signal to the opening / closing mechanism 342 attached to the opening 340 of the common pipe 34 to close the second outside air introduction valve 341. The control unit 60 also sends a drive signal to the opening / closing mechanism 312 attached to the opening 310 of the material inlet pipe 31a connected to the first hopper 10a, which is the selected transport source, to open the third outside air introduction valve 311. The control unit 60 also sends a drive signal to close the discharge valve 27 attached to the second discharge outlet 25 of the second hopper 20.

[0076] Furthermore, a drive signal is supplied from the control unit 60 to a specific switching valve 32a located on the path from the selected first hopper 10a, which is the transport source, to the second hopper 20, which is the transport destination, by driving the drive mechanism 323 to open the material inlet 710. This establishes communication between the material inlet piping 31a and the discharge piping 33a connected to the first hopper 10a. This allows a transport path to be formed for transporting the powder or granular material from the first hopper 10a through the piping unit 30, which includes the material inlet piping 31a, the specific switching valve 32a, the discharge piping 33a, and the common pipe 34, to the second hopper 20. Note that the other switching valves 32b to 32e, which are not on the path from the first hopper 10a to the second hopper 20, have their material inlet 710 closed by driving the drive mechanism 323.

[0077] Furthermore, all valves 37a-37e of the first outside air introduction valve 36, including the specific valve 37a provided in the air inlet pipe 35a connected to the specific switching valve 32a, are closed. Then, at time t0, a drive signal is supplied from the control unit 60 to drive the blower 50 connected to the second hopper 20 via the exhaust pipe 40 (step S1). This causes air to be sucked from the second hopper 20, lowering the air pressure inside the second hopper 20. This causes outside air to be drawn into the piping unit 30 through the opening 310 of the material inlet pipe 31a, generating an airflow from the first discharge port 14 of the first hopper 10a toward the inlet 24 of the second hopper 20. As a result, the powdered or granular material in the first hopper 10a is transported by the airflow through the piping unit 30 to the second hopper 20. In this embodiment, this process of transporting the powdered or granular material from the transport source to the transport destination is referred to as the "main transport" in the transport process.

[0078] As described above, the control unit 60 is preset with an operation sequence S for operating each component during the transport process and the cleaning process described below. When the first operation time has elapsed (time t1) from the start of operation (time t0), the control unit 60 continues driving the blower 50 to suck air from the second hopper 20. While keeping the third outside air introduction valve 311 open, the control unit 60 supplies a drive signal to the opening / closing mechanism 17 attached to the first discharge outlet 14 of the first hopper 10a to close the opening / closing valve 16 (step S2). This stops the discharge of powder and granular material from the first hopper 10a to the material inlet pipe 31a. Meanwhile, outside air continues to flow into the piping unit 30 through the opening 310. As a result, powder and granular material remaining in the piping unit 30, including the material inlet pipe 31a, the specific switching valve 32a, the discharge pipe 33a, and the common pipe 34, can be transported to the second hopper 20. Hereinafter, this process of transporting the powder or granular material remaining in the piping unit 30 to the destination without switching the direction of the airflow in the piping unit 30 will be referred to as "remaining transport" in the transport process.

[0079] After that, when the second operation time has elapsed (time t2) from the start of operation (time t0), the control unit 60, while continuing to drive the blower 50 to suck air from the second hopper 20, issues a command to the first outside air introduction valve 36 to open the specific valve 37a provided in the air inlet pipe 35a connected to the specific switching valve 32a. In response to this command, the opening / closing mechanism 38 opens the specific valve 37a in response to the command from the control unit 60 (step S3). As a result, outside air flows into the casing 321 from the opening 360 at the upstream end of the air inlet pipe 35a, via the air inlet pipe 35a and the air inlet 730 of the specific switching valve 32a, and then flows out through the outlet 720. As a result, powder and granular material remaining in the piping unit 30, which includes the air inlet pipe 35a, the specific switching valve 32a, the discharge pipe 33a, and the common pipe 34, can be transported to the second hopper 20.

[0080] That is, in this embodiment, the powder or granular material still remaining in the piping unit 30 can be transported to the destination by switching the direction of the airflow in the piping unit 30 using the first outside air introduction valve 36. In particular, in step S3, outside air is allowed to flow into the casing 321 through the air inlet 730 of the specific switching valve 32a, so that the powder or granular material still remaining near the air inlet 730 in the casing 321 can be transported to the second hopper 20.

[0081] In this embodiment, after step S2 is completed and step S3 is initiated, the control unit 60 immediately supplies a drive signal to the specific switching valve 32a, causing the drive mechanism 323 to close the material inlet 710. This blocks communication between the material inlet piping 31a and the discharge piping 33a connected to the first hopper 10a. Similarly, the third outside air introduction valve 311 attached to the opening 310 of the material inlet piping 31a is also closed without delay after step S2 is completed and step S3 is initiated. However, the material inlet 710 of the specific switching valve 32a and the opening 310 of the material inlet piping 31a do not necessarily have to be closed.

[0082] Thereafter, when a third operation time has elapsed (time t3) from the start of operation (time t0), the control unit 60 issues a command to the first outside air introduction valve 36 to close the specific valve 37a provided in the air inlet pipe 35a connected to the specific switching valve 32a. Then, the opening / closing mechanism 38 closes the specific valve 37a in response to the command from the control unit 60 (step S4). This stops the inflow of outside air into the casing 321 from the opening 360 at the upstream end of the air inlet pipe 35a via the air inlet pipe 35a and the air inlet 730 of the specific switching valve 32a.

[0083] Hereinafter, this process of switching the direction of the airflow in the piping unit 30 at the first outside air introduction valve 36 and transporting the powder or granular material still remaining in the piping unit 30 to the destination will be referred to as the "cleaning process." In this embodiment, the "cleaning process via the specific switching valve 32a" is completed by executing the steps from opening the specific valve 37a in step S3 to closing the specific valve 37a in step S4.

[0084] Then, when a fourth operation time has elapsed since the start of operation (time t0) (time t4), the control unit 60 issues a command to the first outside air introduction valve 36 to open the valve 37b while sucking air from the second hopper 20. The opening / closing mechanism 38 then opens the valve 37b in response to the command from the control unit 60. This allows outside air to flow from the opening 360 at the upstream end of the air inlet pipe 35b through the air inlet pipe 35b and the air inlet port 730 of the switching valve 32b into the casing 321 and out through the outlet port 720. As a result, powder and granular material remaining in the piping unit 30, including the air inlet pipe 35b, the switching valve 32b, the discharge pipe 33b, and the common pipe 34, can be transported to the second hopper 20. When a fifth operation time has elapsed since the start of operation (time t0) (time t5), the valve 37b is closed, thereby completing the "cleaning process via the switching valve 32b."

[0085] Similarly, after a sixth operation time has elapsed since the start of operation (time t0) (time t6), valve 37c is opened while air is being sucked from the second hopper 20. After a seventh operation time has elapsed since the start of operation (time t0) (time t7), valve 37c is closed, thereby completing the "cleaning process via switching valve 32c." After an eighth operation time has elapsed since the start of operation (time t0) (time t8), valve 37d is opened while air is being sucked from the second hopper 20. After a ninth operation time has elapsed since the start of operation (time t0) (time t9), valve 37d is closed, thereby completing the "cleaning process via switching valve 32d." After a tenth operation time has elapsed since the start of operation (time t0) (time t10), valve 37e is opened while air is being sucked from the second hopper 20. Furthermore, when an eleventh operation time has elapsed (time t11) from the start of operation (time t0), the valve 37e is closed, thereby completing the "cleaning step via the switching valve 32e."

[0086] That is, in this embodiment, after the cleaning process via a specific switching valve 32a located on the route from the selected first hopper 10a, which is the source of transportation, to the second hopper 20, which is the destination of transportation, is completed, cleaning processes via the other switching valves 32b to 32e other than the specific switching valve 32a are executed in sequence (step S5).

[0087] In the above-described transport process, when the powder or granular material in the first hopper 10a is transported to the second hopper 20 through the piping unit 30 including the material inlet piping 31a, the switching valve 32a, the discharge piping 33a, and the common pipe 34, static electricity or the like can cause the powder or granular material to move to unexpected locations such as the other switching valves 32b-32e and the other discharge piping 33b-33e. However, in this embodiment, by sequentially performing the cleaning process via the other switching valves 32b-32e, the powder or granular material still remaining in the other switching valves 32b-32e and the other discharge piping 33b-33e in the piping unit 30 can be transported to its destination in order.

[0088] Then, when a twelfth operating time has elapsed since the start of operation (time t0) (time t12), the control unit 60, while sucking air from the second hopper 20, supplies a drive signal to the opening / closing mechanism 342 attached to the opening 340 at the upstream end of the common pipe 34 to open the second outside air introduction valve 341. This causes outside air to flow into the common pipe 34 from the opening 340 at the upstream end of the common pipe 34, flowing along the transport direction td shown in FIG. 1. As a result, powder or granular material still remaining in the common pipe 34 can be transported to the second hopper 20. Furthermore, when a thirteenth operating time has elapsed since the start of operation (time t0) (time t13), the second outside air introduction valve 341 is closed and the drive of the blower 50 is stopped, thereby completing the "common pipe 34 cleaning process" (step S6).

[0089] When step S6 is completed, the control unit 60 determines that the process of transporting powder and granular material from the first hopper 10a, which is the selected source of transport, and the process of cleaning the piping unit 30 have been completed. This ends the process of transporting powder and granular material from the first hopper 10a, which is the selected source of transport, to the second hopper 20, which is the destination of transport, and the cleaning process in the transport device 1.

[0090] Thereafter, when one of the first hoppers 10a-10e other than the first hopper 10a is newly selected as the powder / granular material transport source, steps S1 to S6 are similarly executed. In this case, before starting step S1, it is desirable to again drive the blower 50 to suck air from the second hopper 20, and then execute the cleaning process of the piping unit 30 via the selector valve 32a, the cleaning process via the selector valve 32b, the cleaning process via the selector valve 32c, the cleaning process via the selector valve 32d, the cleaning process via the selector valve 32e, and the cleaning process of the common pipe 34 in that order. This prevents the remaining powder / granular material from being mixed into the piping unit 30 when the above-described process of transporting powder / granular material from the first hopper 10a and the process of cleaning the piping unit 30 are completed.

[0091] That is, in the present invention, when the transport source of powder or granular material is changed and a new transport source other than the selected one is selected from one or more transport sources, the cleaning process is executed again in sequence via all switching valves and common pipes in the piping unit. This transports the powder or granular material still remaining from all switching valves to just before the destination to the destination. As a result, mixing of the powder or granular material transported from the newly selected transport source with the remaining powder or granular material can be prevented.

[0092] <3. Modifications> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

[0093] In the above embodiment, the blower 50 as the airflow generating means creates a negative pressure at the destination of the powder or granular material, thereby suction-transporting the powder or granular material in the transport device 1. However, the airflow generating means in the present invention may supply positively pressurized air to a selected source, thereby generating an airflow within the piping unit 30 from the selected source to the destination. This allows the transport device 1 to pressure-transport the powder or granular material to the destination. In this case, for example, the blower 50 may be disposed near the opening 310. Furthermore, the means for generating the airflow does not necessarily have to be a blower. In this modification, an airflow from a selected source to a destination can be generated with such a simple structure.

[0094] In the above embodiment, the switching valves 32a-32e are each connected to the downstream end of one of the five material inlet pipes 31a-31e. Each of the switching valves 32a-32e is configured to switch the communication between the downstream end of one of the material inlet pipes 31a-31e and the upstream end of one of the discharge pipes 33a-33e. However, each of the switching valves 32a-32e may be connected to the downstream ends of multiple of the material inlet pipes 31a-31e. Each of the switching valves 32a-32e may be configured to switch the communication between multiple downstream ends of the material inlet pipes 31a-31e and the upstream end of one of the discharge pipes 33a-33e. That is, each of the one or more switching valves of the present invention may be configured to switch the communication between the downstream end of each of the multiple material inlet pipes and the upstream end of one of the one or more discharge pipes.

[0095] The transport device 1 of the present invention may also be configured to transport powder and granular materials other than resin pellets, which are materials for resin molded products, recycled materials, etc. For example, the transport object may be powder and granular materials used in various fields such as pharmaceuticals, chemical products, food, and building materials.

[0096] The detailed configurations of the transport device and the switching device may differ from those shown in the drawings of the present application. Furthermore, the elements appearing in the above-described embodiments and modifications may be combined as appropriate within the scope of not causing any contradiction. [Explanation of symbols]

[0097] 1 Transport device 10a, 10b, 10c, 10d, 10e First hopper 14 (First hopper) First discharge port (connection port) 16 (provided at the first outlet 14) on-off valve 17 (provided at the first discharge port 14) opening / closing mechanism 20 Second Hopper 30 Piping unit 31a, 31b, 31c, 31d, 31e Material inflow piping 32a, 32b, 32c, 32d, 32e Switching valve 33a,33b,33c,33d,33e Discharge piping 34 Common pipe 35a, 35b, 35c, 35d, 35e Air inlet piping 36 First outside air intake valve 37a, 37b, 37c, 37d, 37e (first outside air intake valve) valve 38 (First outside air intake valve) opening and closing mechanism 40 exhaust pipe 50 Blower 60 Control Unit 310 (Material inlet pipe) opening 311 (provided at opening 310) third outside air intake valve 312 (provided in the opening 310) opening / closing mechanism 321 (Switching valve) casing 322 (Switching valve) valve body 323 (Switching valve) drive mechanism 340 (Common pipe) opening 341 Second outside air intake valve (installed in common pipe) 342 (Installed in common pipe) Opening and closing mechanism 360 (Air inlet pipe) opening 710 (Switching valve casing) material inlet 720 (switching valve casing) outlet 730 (Switching valve casing) air inlet td (powder) transport direction

Claims

1. A transport device that transports powder or granular material by airflow from one selected from one or more transport sources through a piping unit to a transport destination, comprising: a switching device that switches the direction of the airflow within the piping unit, The piping unit includes: one or more material inlet pipes, each having an upstream end connected to the one or more transport sources; one or more air inlet pipes, each having an upstream end open to the outside air; a common pipe having a downstream end connected to the transport destination; one or more discharge pipes, each having a downstream end connected to the common pipe; one or more switching valves to which a downstream end of one of the one or more air inlet pipes is connected and which switch communication between the downstream end of the one or more material inlet pipes and an upstream end of one of the one or more discharge pipes; a first outside air introduction valve including one or more valves provided in each of the one or more air inlet pipes, the first outside air introduction valve opening and closing the upstream end of each of the one or more air inlet pipes to outside air; A switching device having:

2. 2. The switching device according to claim 1, A switching device, wherein each of the one or more switching valves switches communication between a downstream end of one of the one or more material inlet pipes and an upstream end of one of the one or more discharge pipes.

3. A switching device according to claim 1 or 2; the one or more shipping sources; The transportation destination; an airflow generating means for generating an airflow in the piping unit from the selected one transport source to the transport destination; A transport device comprising:

4. 4. The transport device of claim 3, The airflow generating means generates an airflow in the piping unit that flows from the selected one transport source to the transport destination by sucking air from the transport destination.

5. 5. The transport device according to claim 3 or claim 4, Each of the one or more switching valves is a casing provided with a material inlet to which a downstream end of the material inlet pipe is connected, an air inlet to which a downstream end of the air inlet pipe is connected, and an outlet to which an upstream end of the discharge pipe is connected; a valve body that opens and closes the material inlet; a drive mechanism for moving the valve body back and forth in a direction perpendicular to the material inlet; and When the valve body opens the material inlet by being driven by the drive mechanism, the powder flows into the casing and flows out from the material outlet, When the valve body closes the material inlet by driving the drive mechanism, the flow of powder and granular material into the casing is stopped.

6. 6. The transport device of claim 5, a control unit electrically connected to the first outside air introduction valve and controlling the opening and closing of each of the one or more valves; and when the control unit issues an open command for the first outside air introduction valve relating to the specific valve and opens the specific valve, outside air flows into the casing through the air inlet pipe and the air inlet in which the specific valve is provided and flows out from the outlet, When the control unit issues a command to close a specific valve to the first outside air introduction valve and closes the specific valve, the flow of outside air into the casing through the air inlet pipe in which the specific valve is installed and the air inlet port is stopped.

7. 7. A transport device according to any one of claims 3 to 6, The piping unit includes: a second outside air introduction valve provided at the upstream end of the common pipe, for opening and closing the upstream end of the common pipe to outside air; The transport device further comprises:

8. 8. A transport device according to any one of claims 3 to 7, A transport device wherein each of the one or more discharge pipes slopes downwardly from horizontal toward a downstream end where the discharge pipes are connected to the common pipe.

9. 9. A transport device according to any one of claims 3 to 8, a support member to which the one or more switching valves are fixed; The transport device further comprises:

10. A switching device according to claim 1; A plurality of said transport sources; The transportation destination; an airflow generating means for generating an airflow in the piping unit from the selected one transport source to the transport destination; and The piping unit includes: a plurality of material inlet pipes, each of whose upstream ends is connected to a plurality of transport sources; and A transport device, wherein each of the one or more switching valves switches communication between a downstream end of each of the plurality of material inlet pipes and an upstream end of one of the one or more discharge pipes.

11. A transportation method for transporting powder or granular material from one selected from one or more transport sources through a piping unit to a transport destination by airflow, and switching the direction of the airflow within the piping unit, comprising: The piping unit includes: one or more material inlet pipes, each having an upstream end connected to the one or more transport sources; one or more air inlet pipes, each having an upstream end open to the outside air; a common pipe having a downstream end connected to the transport destination; one or more discharge pipes, each having a downstream end connected to the common pipe; one or more switching valves to which a downstream end of one of the one or more air inlet pipes is connected and which switch communication between the downstream end of the one or more material inlet pipes and an upstream end of one of the one or more discharge pipes; a first outside air introduction valve including one or more valves provided in each of the one or more air inlet pipes, the first outside air introduction valve opening and closing the upstream end of each of the one or more air inlet pipes to outside air; and Each of the one or more switching valves is a casing provided with a material inlet to which a downstream end of the material inlet pipe is connected, an air inlet to which a downstream end of the air inlet pipe is connected, and an outlet to which an upstream end of the discharge pipe is connected; a valve body that opens and closes the material inlet; a drive mechanism for moving the valve body back and forth in a direction perpendicular to the material inlet; and a) a step of transporting powder or granular material from the selected one transport source to the transport destination by driving the drive mechanism to open the material inlet port of the specific switching valve located on the route from the selected one transport source to the transport destination, thereby communicating the material inlet pipe connected to the selected one transport source with the discharge pipe, and sucking air from the transport destination; b) after step a), while air is being sucked from the transport destination, issuing an open command for the valve provided in the air inlet pipe connected to the specific switching valve, and opening the valve to allow outside air to flow into the casing through the air inlet pipe and the air inlet; A transportation method comprising:

12. 12. The method of claim 11, further comprising: c) after step a), a step of blocking the communication between the material inlet pipe and the discharge pipe connected to the selected one transport source by driving the drive mechanism in the specific switching valve to close the material inlet port. The transportation method further comprises:

13. 13. The method of claim 11 or 12, d) after continuing step b) for a predetermined time, issuing a command to close the valve provided in the air inlet pipe connected to the specific switching valve, thereby stopping the inflow of outside air into the casing via the air inlet pipe and the air inlet. By further having performing a cleaning process consisting of the process b) and the process d) via the specific switching valve; Transportation method.

14. 14. The method of claim 13, further comprising: e) a transportation method in which, after step d), the cleaning steps are sequentially performed via other switching valves other than the specific switching valve among the one or more switching valves in the piping unit.

15. 15. The method of claim 13 or claim 14, The piping unit includes: a second outside air introduction valve provided at the upstream end of the common pipe, for opening and closing the upstream end of the common pipe to outside air; and f) after step d), a step of opening the second outside air introduction valve while sucking air from the transport destination, thereby allowing outside air to flow into the common pipe from the upstream end of the common pipe. The transportation method further comprises:

16. 16. The method of transport according to any one of claims 13 to 15, h) A transportation method in which, when a transportation source other than the selected one is selected from the one or more transportation sources, the cleaning process is again performed in sequence, passing through all of the one or more switching valves in the piping unit, while air is again sucked from the transportation destination.

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