CN108946170B

CN108946170B - Method and apparatus for conveying powder material

Info

Publication number: CN108946170B
Application number: CN201810374137.1A
Authority: CN
Inventors: 助川义纪
Original assignee: Matsui Universal Joint Manufacturing Co
Current assignee: Matsui Universal Joint Manufacturing Co
Priority date: 2017-05-24
Filing date: 2018-04-24
Publication date: 2022-05-24
Anticipated expiration: 2038-04-24
Also published as: JP2018197148A; JP6829883B2; CN108946170A

Abstract

A method for transporting a powdered or granular material, wherein the powdered or granular material from a transport source (10) is transported by air by switching it to a plurality of collection units (30A-30E), wherein if a predetermined transport start condition is satisfied in a state where the level of accumulation of the powdered or granular material in any one of the collection units is lower than the 1 st level (LV1), a transport air source (20) is operated to transport the powdered or granular material to a collection unit of a priority transport target, and if a collection unit of a sub-transport target lower than the 1 st level is present in a state where the transport start condition is satisfied, the transport target is switched to the collection unit of the sub-transport target and transported.

Description

Method and device for transporting powder material

Technical Field

The present invention relates to a method and an apparatus for conveying a powder or granular material, which convey a powder or granular material as a conveyance source to a collection unit through air.

Background

Conventionally, a powder or granular material transport apparatus has been known which transports a powder or granular material from a transport source to respective collection units disposed in a plurality of supply targets by air.

For example, patent document 1 discloses a pneumatic conveying device for conveying resin pellets stored in a powder/granular material storage tank to receiving hoppers attached to a plurality of molding machines by using a suction air box. Patent document 1 discloses a pneumatic conveying apparatus in which a main connection line connected to a powder/granular material storage tank is connected to each receiving hopper via a branch connection line branched from a switching valve, an air line for sucking air separated from resin particles in a bag filter is connected to an upper portion of each receiving hopper, and an on-off valve is provided in each air line. In addition, the pneumatic conveying apparatus is configured to feed resin pellets or stop feeding for each receiving hopper by operating a switching valve and an opening/closing valve based on detection of a level gauge provided on each receiving hopper.

Further, patent document 1 discloses an air-operated conveying device having a configuration in which a plurality of hoppers are connected in series to a powder/granular material storage unit via a connection pipe, and a suction air box is connected to the last hopper via a bag filter. The pneumatic conveying device has the following structure: when the level meter of one of the plurality of hoppers detects the lower limit level, the suction wind box is operated, and when the hoppers connected to the hopper detecting the lower limit level are sequentially filled with resin pellets, the hopper detecting the lower limit level is filled with resin pellets, and when the level meter detects the upper limit level, the suction wind box is stopped.

Patent document 1: japanese laid-open patent publication No. 11-139561

However, in the former pneumatic conveying apparatus described in patent document 1, since the pneumatic conveying is performed according to the receiving hopper based on the detection of the level gauge, the number of times of conveying tends to increase, and therefore, the suction bellows may be frequently opened and closed, and useless time such as a rise time may be frequently generated. Further, if the transport source is a drying device that accumulates and dries the powdered or granular material, the outside air easily flows into the drying device each time it is transported, and if the powdered or granular material is exposed to the outside air, moisture absorption or oxidation may occur.

Further, in the latter pneumatic conveying apparatus described in patent document 1, since it is necessary to fill each hopper connected to the hopper whose lower limit level is detected with resin pellets in sequence, shortage of material (insufficient feeding) occurs in the hopper whose lower limit level is detected, or the hopper closer to the conveying source is filled with resin pellets every time the conveying is performed, so that the retention time in the hopper tends to be long.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method and an apparatus for conveying a powder or granular material, which can reduce the number of times of conveyance and shorten the residence time of the powder or granular material in a collection portion.

In order to achieve the above object, a method of transporting a powder or granular material according to the present invention is a method of transporting a powder or granular material by switching a transport source of the powder or granular material to a plurality of collection units and carrying the powder or granular material through air, wherein if a predetermined transport start condition is satisfied in a state where a level of accumulation of the powder or granular material in any one of the plurality of collection units is lower than a 1 st level, a transport air source is operated to transport the powder or granular material to a collection unit of a priority transport target, and if a collection unit of a sub-transport target lower than the 1 st level is present in a state where the transport start condition is satisfied, the transport target is switched to a collection unit of the sub-transport target and carried.

In order to achieve the above object, a powder/granular material conveying apparatus according to the present invention is a powder/granular material conveying apparatus for switching a conveying source of a powder/granular material to a plurality of collection units and performing air conveyance, the powder/granular material conveying apparatus including: a 1 st level detection unit that detects a 1 st level as a level of accumulation of the particulate material in each of the plurality of collection units; a conveyance start condition detection unit that detects satisfaction of a predetermined conveyance start condition in a state lower than the 1 st level; and a control unit that, if it is detected that the conveyance start condition is satisfied in a state where it is detected that the accumulated level of any one of the plurality of collecting units is lower than the 1 st level, activates the conveyance air source to convey the powdered or granular material to the collecting unit of the conveyance target of priority, and if it is detected that the conveyance start condition is satisfied, switches the conveyance target to the collecting unit of the secondary conveyance target and conveys the powdered or granular material.

Effects of the invention

According to the transport method of a powder or granular material of the present invention and the transport apparatus of a powder or granular material according to the present invention configured as described above, the number of times of transport can be reduced and the retention time of the powder or granular material in the collection portion can be shortened.

Drawings

Fig. 1 is a schematic system configuration diagram schematically showing an example of a powder and granular material conveying apparatus according to an embodiment of the present invention used for a method of conveying a powder and granular material according to an embodiment of the present invention.

Fig. 2 is a schematic flowchart schematically showing an example of a basic operation (conveying method) executed in the conveying apparatus.

FIG. 3 (a-1) to FIG. 3 (b-5) are partially sectional schematic longitudinal sectional views schematically showing an example of a trap part provided in the transport apparatus.

FIG. 4 (c-1) to FIG. 4 (d-5) are partially sectional schematic longitudinal sectional views schematically showing an example of a trap part provided in the transport apparatus.

FIG. 5 (e-1) to FIG. 5 (f-5) are partially sectional schematic longitudinal sectional views schematically showing an example of a trap part provided in the transport apparatus.

FIG. 6 (g-1) to FIG. 6 (h-5) are partially sectional schematic longitudinal sectional views schematically showing an example of a trap part provided in the transport apparatus.

Fig. 7 is a schematic flowchart schematically showing an example of a method for conveying a powder or granular material according to another embodiment of the present invention.

Description of the reference symbols

1 conveying device for powder material

10 drying device (transportation source)

20 conveying air source

30A-30E trap part

33A to 33E Upper level meter (level detecting part 1.)

34A to 34E lower level meters (conveyance start condition detecting section)

36 control part (conveying start condition detecting part)

39A to 39E trap level meters (level detecting section 1.)

Level 1 LV1

Level 2 LV2

t1 time 1

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

In fig. 1, a pipeline (piping) or the like as a path through which the transport air and the powdered or granular material pass is schematically shown by a solid line.

In addition, detection and opening/closing, ON/OFF, and the like of each device are schematically shown in the schematic flowcharts in fig. 2 and 7.

Fig. 1 to 6 are diagrams schematically showing an example of a method of conveying a powder or granular material and an example of a device for conveying a powder or granular material according to embodiment 1.

The method for conveying a powder or granular material according to the present embodiment is performed using the apparatus 1 for conveying a powder or granular material according to the present embodiment. The method for conveying the powder or granular material according to the present embodiment can be performed using another conveying apparatus.

As shown in fig. 1, the powder or granular material transport apparatus 1 is configured to transport the powder or granular material from the transport source 10 to the plurality of collection units 30A to 30E by air. The particulate material collected in the collection portions 30A to 30E is supplied to the supply targets 6A to 6E. In the present embodiment, the powdered or granular material of the material source 2 can be transported to the transport source 10.

Here, the powder material refers to a powder/particle material, but includes a material in the form of a fine flake or a short fiber sheet/strip.

The material may be a synthetic resin material such as resin particles or resin fiber sheets, a metal material, a semiconductor material, a wood material, a pharmaceutical material, a food material, or the like.

Examples of the particulate material include natural materials (virgin materials), pulverized materials, base materials, and various additives when a synthetic resin molded article is molded. The particulate material may be a structure containing reinforcing fibers such as glass fibers or carbon fibers.

The conveyance source 10 is a drying device 10 for drying the powdered or granular material in the present embodiment. The drying device 10 includes a hopper-shaped reservoir 11 for storing the powder/granular material, a heat source 12 for heating the powder/granular material in the reservoir 11, and a vacuum pump 13 as a vacuum generation source for reducing the pressure in the reservoir 11. That is, the drying device 10 is a reduced pressure type drying device that heats the powder or granule material while reducing the pressure in the reservoir 11.

The heat source 12 is a heater 12 provided along the outer peripheral surface of the storage 11, and is a heat transfer type heat source that indirectly heats the powder/granular material through the side peripheral wall of the storage 11. A cylindrical body extending in the vertical direction and incorporating a heater 12 is provided in the center portion of the reservoir 11 in a plan view. A plurality of heat transfer fins protruding in the radial direction are provided at intervals in the circumferential direction on the inner circumferential wall of the reservoir 11 and the outer circumferential surface of the cylindrical body. Further, a heat insulator or the like may be provided on the outer peripheral side of the reservoir 11. Further, instead of or in addition to this, the heating source 12 for heating the powder/granular material in the storage 11 may be a heated gas supply unit for supplying gas heated by a heater or the like into the storage 11, or may be variously configured.

The vacuum pump 13 is connected to the reservoir 11 via a vacuum suction line. In the figure, an example is shown in which a vacuum suction line is connected to an upper portion of the reservoir 11. A filter is provided on the suction side of the vacuum pump 13. The reduced pressure state in the reservoir 11 by the vacuum pump 13 is a vacuum state in which the pressure in the reservoir 11 is lower than the atmospheric pressure, but the pressure in the reservoir 11 may be temporarily set to the atmospheric pressure or higher by introducing a gas introduced for preventing solidification (bridging) of the powder/granular material in the reservoir 11, or the like.

The vacuum pump 13 may be, for example, a pump capable of reducing the pressure so that the vacuum in the reservoir 11 reaches a degree of vacuum of about 20kPa (abs) to 4kPa (abs).

Further, the vacuum suction line is provided with an atmosphere opening valve 14, a pressure gauge such as a pressure sensor or a pressure gauge for detecting the degree of vacuum, and the like. Instead of the vacuum pump 13, another vacuum generation source such as an ejector device may be used.

Further, an input valve 16 as a material input portion that is opened and closed when the powder and granular material is input (supplied) to the storage portion 11 is provided on the upper end side of the storage portion 11. The input valve 16 is provided between an input pipe provided on the upper end side of the storage portion 11 and a transport source collection portion 17 for collecting the particulate material from the material source 2. The input valve 16 is configured to hermetically block the input pipe (the reservoir 11) and the conveyance source trap 17 in a closed state. On the other hand, if the input valve 16 is opened, the powder or granular material collected in the conveyance source collection unit 17 is input into the storage unit 11 through the input pipe. The input valve 16 may be a slide gate including a plate-shaped valve body that slides in a direction orthogonal to the axial direction of the pipe so as to cross the pipe by a driving unit such as an air cylinder, or may have various configurations.

Further, a transfer source level meter 15 is provided in the reservoir 11. In the present embodiment, the conveyance source level meter 15 is provided in a feed pipe provided in series with the upper end side of the reservoir 11. Further, an example is shown in which the conveyance source level meter 15 is an upper limit level meter for detecting a full level as a level of accumulation of the powder/granular material in the accumulation portion 11. Namely, the structure is as follows: the detection of the presence of the material by the conveyance source level meter 15 serves as a trigger signal for stopping conveyance to the storage unit 11. Instead of this, the conveyance source level meter 15 may be a required (lower limit) level meter in which the detection material required level is set as the accumulation level of the particulate material in the accumulation portion 11. In this case, another level meter for detecting the full level, a configuration in which the conveyance to the storage unit 11 is performed until a predetermined conveyance time set in advance has elapsed, or the like may be provided.

The transport source collection unit 17 is configured to collect the powder/granular material transported by air from the material source 2. The material supply pipe 3 connected to the material source 2 and the supply-source-side pipe 4 as an air pipe connected to the supply air source 20 are connected to the supply-source trap 17. In the present embodiment, the conveyance air source 20 driven when the powdered or granular material of the material source 2 is air-conveyed (primary conveyance) to the drying device 10 and the conveyance air source 20 driven when the powdered or granular material of the drying device 10 as the conveyance source is air-conveyed (secondary conveyance) by switching the powdered or granular material to the plurality of collection sections 30A to 30E are made to be a common conveyance air source. That is, the primary conveyance and the secondary conveyance can be performed by the single conveyance air source 20. Further, the powder/granular material of the material source 2 is sucked and conveyed by communicating the suction side of the conveyance air source 20 to the conveyance source side pipe 4.

The transport source trap 17 is provided with a separation unit such as a filter for separating the transport air from the powder and granular material transported by air through the material transport line 3.

The powder or granular material collected in the conveyance source collection unit 17 drops by its own weight and is stored in the storage unit 11 if the input valve 16 is opened.

The material source 2 may be a material tank, a weighing hopper for weighing the powder or granule material, a blending hopper for blending a plurality of powder or granule materials at a predetermined ratio, or the like. Further, a temporary reservoir provided downstream of these various hoppers may be used as the material source 2. The method of connecting the material transfer line 3 to the single material source 2 to transfer the single powder/granular material to the storage 11 is not limited to the method of connecting the material transfer line to the single material source 2, and may be a method of connecting the material transfer line to a plurality of material sources 2 that store different powder/granular materials, respectively, and transferring a plurality of types of powder/granular materials to the storage 11.

Further, a discharge valve 19 as a material discharge portion is provided in a discharge pipe 18 provided to be connected to the lower end side of the reservoir 11 of the drying device 10. The discharge valve 19 may be a slide flapper as described above, but in the present embodiment, a push flapper including a valve body that slides in the pipe axis direction by the same driving unit to close the discharge port is used. Further, a discharge port opened and closed by a valve body of the discharge valve 19 may be provided at an end of a pipe line provided horizontally or obliquely with respect to the discharge pipe 18 in the vertical direction with respect to the axial direction via a bent portion. Further, a connecting portion for connecting the material transfer pipe 21 communicating with the plurality of trap portions 30A to 30E and the air pipe 28 communicating with the transfer air source 20 may be provided on the downstream side of the valve body of the discharge valve 19. The discharge valve 19 is configured to hermetically block the reservoir 11 from a downstream connection portion in a closed state. Further, when the powder or granular material is conveyed with the discharge valve 19 opened and the conveyance air source 20 activated, it may be necessary to introduce conveyance auxiliary air. In addition, various configurations can be adopted as a material discharge unit for discharging the powder or granular material of the drying device 10 as a transport source.

The supply targets 6A to 6E of the particulate material collected by the plurality of collection units 30A to 30E are the molding machines 6A to 6E in the present embodiment.

These molding machines 6A to 6E may be injection molding machines or the like, for example, and in the present embodiment, the respective trap portions 30A to 30E are directly provided to the respective molding machines 6A to 6E. Instead of this, a system of further air-conveying toward the molding machines 6A to 6E may be used. The molding machines 6A to 6E to be supplied are not limited to injection molding machines for molding synthetic resin molded articles, and may be injection molding machines for other materials, or may be other molding machines such as extrusion molding machines or compression molding machines for various materials. The targets 6A to 6E for supply to the respective trap units 30A to 30E are not limited to the molding machine, and may be a hopper, a drying device, a blending device, or the like on the molding machine.

The transport apparatus 1 for powdered or granular material includes 1 st level detection units 33A to 33E for detecting the 1 st level LV1 as a level of accumulation of powdered or granular material in each of the plurality of collection units 30A to 30E, transport start condition detection units 34A to 34E for detecting satisfaction of a predetermined transport start condition in a state of being lower than the 1 st level LV1, and a control panel 35 having a control unit 36 for executing predetermined transport control described later.

In the present embodiment, the plurality of collecting portions 30A to 30E are constituted by the 1 st collecting portion 30A, the 2 nd collecting portion 30B, the 3 rd collecting portion 30C, the 4 th collecting portion 30D, and the 5 th collecting portion 30E. The 1 st collecting portion 30A is provided in the 1 st forming machine 6A as a supply target. The 2 nd collecting portion 30B is provided in the 2 nd forming machine 6B as a supply target. The 3 rd collecting portion 30C is provided in the 3 rd forming machine 6C as a supply target. The 4 th collecting unit 30D is provided in the 4 th molding machine 6D as a supply target. The 5 th collecting part 30E is provided in the 5 th forming machine 6E as a supply target.

These plurality of trap portions 30A to 30E have a function of temporarily accumulating, in addition to the function of trapping. Further, these plurality of trap portions 30A to 30E may also have a dust removing function or a mixing function.

In the present embodiment, the plurality of trap portions 30A to 30E may have the same configuration. Instead of this, the plurality of collecting units 30A to 30E may have different configurations, for example, different capacities depending on the processing capacities (the amount of powder/granular material processed (consumed) per unit time) of the molding machines 6A to 6E to be supplied.

These collection portions 30A to 30E include main body portions 31A to 31E for collecting the powder or granular material pneumatically conveyed from the drying device 10, and reservoir portions 32A to 32E for storing the powder or granular material collected in the main body portions 31A to 31E.

The main bodies 31A to 31E are formed in a hopper shape. The main bodies 31A to 31E are connected to the delivery pipes 23A to 23E communicating with the drying device 10 and the air pipes 24A to 24E communicating with the delivery air source 20. Further, the main bodies 31A to 31E are provided with a separating portion for separating the transport air from the powder or granular material air-transported through the transport ducts 23A to 23E, similarly to the transport source trap 17. Further, the separation portions of the main bodies 31A to 31E and the conveyance source trap 17 may be configured to separate the particulate material from the conveyance air by a so-called cyclone. Further, a discharge valve or the like that is closed at the time of air conveyance may be provided at the lower end side of the main bodies 31A to 31E.

In the present embodiment, the conveying lines 23A to 23E are branched from the material conveying line 21 connected to the discharge side of the drying device 10 via the branching portion 22. The branch portion 22 includes downstream side connection portions 22a to 22E connected to the respective plurality of (5 in the present embodiment) conveyance lines 23A to 23E, and an upstream side connection portion 22f connected to the single material conveyance line 21. That is, the branch portion 22 includes a plurality of (5 in the present embodiment) downstream side connection portions 22a to 22e branched from a single upstream side connection portion 22 f. The branch portion 22 is not switched by a switching valve or the like, but is configured to convey the powder or granular material to one of the downstream side connection portions 22a to 22e on which the negative pressure acts. That is, the powder or granular material of the drying device 10 is conveyed toward the conveying line communicating with the conveying air source 20 among the conveying lines 23A to 23E via the branch portion 22.

The air lines 24A to 24E are communicated with the single conveyance air source 20 via the conveyance target switching valve 25 in the present embodiment.

The transfer target switching valve 25 includes upstream connecting portions 25a to 25E connected to the respective air lines 24A to 24E (5 lines in the present embodiment), and a downstream connecting portion 25f connected to a single air source line 27 on the transfer air source 20 side. The transfer target switching valve 25 is provided with switching valves 26A to 26E each having a valve body for opening and closing a downstream opening provided on the downstream side of the upstream connecting portions 25a to 25E. These switching valves 26A to 26E may be configured such that the valve body is slid by a driving unit such as an air cylinder, as described above.

If one of the switching valves 26A to 26E (for example, the 1 st switching valve 26A) is opened and the other switching valves (the 2 nd switching valves 26B to the 5 th switching valves 26E) are closed, the air line (the 1 st air line 24A) corresponding to the opened switching valve among the air lines 24A to 24E and the air source side line 27 communicate with each other. On the other hand, the air lines (2 nd to 5 th air lines 24B to 24E) corresponding to the closed switching valves are blocked from the air source side line 27. As an embodiment for switching the conveyance target, instead of providing a single conveyance target switching valve 25, a configuration may be adopted in which a plurality of switching valves are provided. In this case, a configuration such as a junction substantially similar to the branching section 22 that joins the single air source-side pipe line 27 may be adopted. In addition, instead of the above-described manner in which the conveyance target switching valve 25 is provided on the air lines 24A to 24E side, or a manner in which a valve for switching the conveyance target is provided on the conveyance lines 23A to 23E side may be employed.

The air source-side pipe 27 and the conveyance source-side pipe 4 connected to the conveyance source trap 17 communicate with an air pipe 28 in which the conveyance air source 20 is disposed, via the conveyance air switching valve 5. The feed air switching valve 5 includes a primary side connection portion 5a connected to the feed source side pipe 4, a secondary side connection portion 5b connected to the air source side pipe 27, and a downstream side connection portion 5c connected to the air pipe 28. The transport air switching valve 5 is provided with a drive unit such as an air cylinder that drives a valve body configured to open one of downstream openings provided on the downstream sides of the primary side connecting portion 5a and the secondary side connecting portion 5b if the other is closed. If the valve body of the transport air switching valve 5 is set to a state in which the downstream side opening of the primary side connecting portion 5a is closed (if switched to the secondary side), secondary transport is enabled. On the other hand, if the valve body of the transport air switching valve 5 is set to a state in which the downstream side opening of the secondary side connecting portion 5b is closed (if switched to the primary side), primary transport is possible.

A filter 29 for trapping foreign matters, dust, and the like contained in the conveyance air is disposed on the upstream side of the conveyance air source 20 in the air line 28. Further, a cyclone filter may be provided upstream of the filter 29.

The conveyance air source 20 is a suction air box connected to the conveyance air switching valve 5 on the upstream side of the intake side of the air line 28 and to the discharge valve 19 on the downstream side of the discharge side of the air line 28. In addition, an inverter or the like may be provided to change the rotation speed of the drive motor of the air supply source 20 according to the pipe diameter of the distribution pipe, the type of the powder material, and the like.

The transport air is not limited to the atmosphere, and may be dehumidified dry air or an inert gas having a low oxygen content such as nitrogen or argon. In this case, a configuration may be adopted in which a dryer for dehumidifying the transport air, a separation membrane for generating nitrogen or the like, or the like is provided in the circulation path of the transport air, or a configuration may be adopted in which dry air or inert gas is supplied from another path to the circulation path.

The reservoirs 32A to 32E of the plurality of trap portions 30A to 30E are formed in a cylindrical shape in the present embodiment. Instead of this, some or all of the plurality of reservoirs 32A to 32E may be formed in a hopper shape.

The discharge ports at the lower ends of these reservoirs 32A to 32E are connected to the molding machines 6A to 6E, and communicate with the inlets of the molding machines 6A to 6E to be supplied. The powder/granular material accumulated in these reservoirs 32A to 32E is supplied to the respective molding machines 6A to 6E in a manner of a bleed flow. That is, as the powder particle materials are processed (consumed) in the molding machines 6A to 6E, the level of accumulation in the respective accumulation portions 32A to 32E (the respective collection portions 30A to 30E) is lowered. Further, a discharge portion or the like that discharges a fixed amount toward each of the molding machines 6A to 6E may be provided at the lower end of each of the reservoirs 32A to 32E.

In the present embodiment, the upper level meters 33A to 33E as the 1 st level detection unit that detects the 1 st level LV1 may be provided in the respective reservoirs 32A to 32E.

As shown in fig. 3 (a-1) to 3 (a-5), the upper level meters 33A to 33E are arranged to detect the 1 st level LV1 at the halfway position in the vertical direction as the accumulation levels of the respective accumulation portions 32A to 32E. In the figure, an example is shown in which the upper level gauges 33A to 33E are disposed so as to detect the 1 st level LV1 at substantially the center in the vertical direction of the respective reservoirs 32A to 32E.

In the present embodiment, each of the reservoirs 32A to 32E is configured to be provided with lower level meters 34A to 34E as a 2 nd level detector for detecting a 2 nd level LV2 lower than the 1 st level LV1 as a conveyance start condition detector (a 2 nd conveyance start condition detector for detecting a 2 nd conveyance start condition described later).

The lower level meters 34A to 34E are arranged to detect the 2 nd level LV2 at a lower side portion than the vertical direction center portion as the reservoir levels of the respective reservoirs 32A to 32E. In the figure, an example is shown in which these lower level meters 34A to 34E are disposed so as to detect the 2 nd level LV2 at a height position of approximately 1/6 from the lower end side of each of the reservoirs 32A to 32E in the vertical direction. The positions at which the upper gradienters 33A to 33E and the lower gradienters 34A to 34E are provided are not limited to the positions shown in the drawing, as long as the 2 nd level LV2 detected by the lower gradienters 34A to 34E is lower than the 1 st level LV1 detected by the upper gradienters 33A to 33E. For example, the upper level gauges 33A to 33E may be provided to detect positions above the illustration, and the lower level gauges 34A to 34E may be provided to detect levels at substantially central portions in the vertical direction of the respective reservoirs 32A to 32E.

In the present embodiment, the upper level gauges 33A to 33E and the lower level gauges 34A to 34E are non-contact sensors. Such a non-contact sensor may be an electromagnetic induction type, a capacitance type, an ultrasonic wave type, a photoelectric type, or the like. The upper level gauges 33A to 33E and the lower level gauges 34A to 34E are not limited to the non-contact sensors, and may be contact sensors such as a pedal type or a vibration type. Instead of providing the upper level meters 33A to 33E and the lower level meters 34A to 34E for detecting the 1 st level LV1 and the 2 nd level LV2, respectively, a single ultrasonic level meter, a microwave level meter, a capacitance type continuous level meter, or other multi-stage (multi-stage) level meter or continuous level meter capable of detecting the 1 st level LV1 and the 2 nd level LV2 may be used.

In the drawing, the 1 st level LV1 and the 2 nd level LV2 in each of the reservoirs 32A to 32E are set to be substantially the same level (height positions), but may be different levels. Further, the storage capacity from the 2 nd level LV2 to the 1 st level LV1 may be changed in accordance with the throughput of each of the molding machines 6A to 6E so that the processing time for processing the particulate material stored in the respective storage portions 32A to 32E from the 2 nd level LV2 to the 1 st level LV1 may be substantially the same (or may be an integral multiple of a certain processing time). For example, the height position of one or both of the upper level gauges 33A to 33E and the lower level gauges 34A to 34E may be changed.

The control panel 35 includes: a control unit 36 configured by a CPU or the like; a display operation unit 37 connected to the control unit 36 via a signal line or the like, and constituting a display unit and an operation unit for setting, inputting, or displaying various settings or the like; the storage unit 38 stores various programs such as setting conditions and input values set and input by the operation of the display operation unit 37, control programs for executing modes and the like described later, various preset operating conditions, various data tables, and the like, and is configured by various memories and the like. The control panel 35 may be provided in the transport device 1 for the powdered or granular material, or may be provided in any device constituting a transport system including the transport device 1 for the powdered or granular material. The control panel 35 may be provided at an appropriate position of the transport apparatus 1 for powdered or granular material, or may be provided at a position away therefrom. In the figure, an example is shown in which the control panel 35 is provided adjacent to the drying device 10.

The control unit 36 may include a timer unit such as a clock timer, an arithmetic processing unit, and the like, and be connected to and control the devices (the heater 12, the vacuum pump 13, the atmosphere opening valve 14, the input valve 16, and the discharge valve 19) of the drying apparatus 10, or the devices necessary for the operation of the transport apparatus 1 for the powder or granular material such as the transport air source 20, the transport air switching valve 5, and the transport target switching valve 25, via signal lines and the like. The control unit 36 is also connected to various detection devices such as the above-described conveyance source level meter 15, upper level meters 33A to 33E, and lower level meters 34A to 34E via signal lines and the like. The control unit 36 may be connected to a material sensor or a discharge unit of the material source 2 as necessary.

The control unit 36 is configured to execute the following control: if the satisfaction of the predetermined conveyance start condition is detected in a state where the accumulated level of any one of the plurality of collecting units 30A to 30E is detected to be lower than the 1 st level LV1, the conveyance air source 20 is operated to convey the powdered or granular material to the collecting unit of the priority conveyance target, and if the collection unit of the sub conveyance target lower than the 1 st level LV1 is detected in a state where the conveyance start condition is satisfied, the conveyance target is switched to the collection unit of the sub conveyance target and conveyed. In the present embodiment, the control unit 36 is configured to execute the following control: if the lower than 2 nd level LV2 is detected in a state where the accumulation level of any one of the plurality of collecting units 30A to 30E is detected to be lower than the 1 st level LV1, the conveyance air source 20 is operated to convey the powdered or granular material to the collecting unit of the priority conveyance target lower than the 2 nd level LV2, and if the collecting unit of the sub conveyance target lower than the 1 st level LV1 is detected in a state where the collecting unit of the priority conveyance target is lower than the 2 nd level LV2, the conveyance target is switched to the collecting unit of the sub conveyance target and conveyed.

The control unit 36 is configured to execute the following control: if it is detected that the accumulation level of the particulate material in any one of the plurality of collection sections 30A to 30E is lower than the 1 st level LV1 and if it is detected that the accumulation level of a predetermined number of collection sections is lower than the 1 st level LV1, it is determined that the conveyance start condition (the 1 st conveyance start condition described later) is satisfied, and the particulate material is conveyed to the collection sections lower than the 1 st level LV 1. That is, the control unit 36 also functions as a 1 st conveyance start condition detection unit that detects a 1 st conveyance start condition.

Hereinafter, a specific example of a method for conveying a powder or granular material, which is an example of a basic operation performed in the powder or granular material conveying apparatus 1 according to the present embodiment having the above-described configuration, will be described with reference to fig. 2 to 6. The following operation example is executed by the control of the control unit 36. In the following example, a delay time may be set for the opening/closing operation of each valve or the ON/OFF operation of each device, or the opening/closing operation of each valve and the ON/OFF operation of each device may be sequentially performed.

First, as shown in fig. 2, in an initial preparation stage in which a system (molding system) including the transport apparatus 1 for the powdered or granular material is started, if the drying apparatus 10 is in an empty state or a material request state, a primary transport mode in which the powdered or granular material of the material source 2 is transported to the drying apparatus 10 is executed. In the present embodiment, if a material request signal (no material signal) is output from the conveyance source level meter 15 of the drying device 10 (if the material (full) signal disappears), the one-time conveyance mode is executed. In the primary conveyance mode, the discharge valve 19 is closed, the atmosphere opening valve 14 and the introduction valve 16 are opened, and the conveyance air source 20 is set to a start (ON) state. In the primary transport mode, the transport-source-side pipe 4 and the air pipe 28 are communicated, and the transport-air switching valve 5 is switched to the primary side so that the air-source-side pipe 27 and the air pipe 28 are blocked.

Thereby, the powder or granular material of the material source 2 is air-conveyed (primary conveyance) toward the conveyance source collection unit 17 of the drying device 10, separated from the conveyance air in the conveyance source collection unit 17, and is charged into the drying device 10.

In the primary conveyance mode, the vacuum pump 13 of the drying device 10 may be stopped (OFF) and the heater 12 may be activated. In the primary conveyance mode, the switching valves 26A to 26E of the conveyance target switching valve 25 are closed.

In the primary transport mode in the initial preparation stage, the material request signal (no material signal) is output from the upper level meters 33A to 33E of the 1 st level detection unit and the lower level meters 34A to 34E of the 2 nd level detection unit constituting the collection units 30A to 30E (the accumulated level is lower than the 2 nd level LV 2) (see also fig. 3 (a-1) to 3 (a-5)). In the primary conveyance mode in the initial preparation stage, the molding machines 6A to 6E are stopped or stopped.

Then, the primary conveyance mode is executed in the initial preparation stage, and if a material (full level) signal is output from the conveyance source level meter 15 of the drying device 10, the primary conveyance mode is shifted to the reduced pressure drying mode. In the reduced-pressure drying mode, the atmosphere opening valve 14 and the input valve 16 are closed, the air supply source 20 is stopped, and the vacuum pump 13 is started. In the decompression drying mode, the air source-side pipe 27 and the air pipe 28 are communicated, and the conveyance air switching valve 5 is switched to the secondary side so that the conveyance source-side pipe 4 and the air pipe 28 are blocked. Thereby, the powder or granule material in the drying device 10 is heated and dried in a reduced pressure state. In the case of drying under reduced pressure in this manner, a gas (purge gas) may be introduced into the drying apparatus 10 to replace the air in the drying apparatus 10, or a gas for applying an impact may be introduced into the drying apparatus 10 to prevent a so-called bridging phenomenon of the powder/granular material. The switching of the transfer air switching valve 5 to the secondary side may be performed when a secondary transfer mode, which will be described later, is executed.

Then, if the powdered or granular material in the drying device 10 is dried and the material request signals are output from the upper level meters 33A to 33E and the lower level meters 34A to 34E of the respective collection units 30A to 30E, the secondary conveyance mode is executed. In the secondary conveyance mode at the initial preparation stage, when the respective trap units 30A to 30E are in the empty state, the conveyance target may be sequentially switched to the respective trap units 30A to 30E to perform air conveyance (secondary conveyance). In the secondary conveyance mode, the discharge valve 19 and the atmosphere opening valve 14 are opened, the vacuum pump 13 is stopped, and the conveyance air source 20 is started. In the secondary conveyance mode in the initial preparation stage, the respective switching valves 26A to 26E of the conveyance target switching valve 25 may be opened and closed, and the collection units 30A to 30E may be performed in an appropriate order. In the figure, an example is shown in which the secondary conveyance is performed in the order of the 1 st collecting part 30A, the 2 nd collecting part 30B, the 3 rd collecting part 30C, the 4 th collecting part 30D, and the 5 th collecting part 30E.

When the powder or granular material of the drying device 10 is air-conveyed to the 1 st trap portion 30A, the 1 st switching valve 26A is opened, and the other switching valves 26B to 26E are closed. When the powder or granular material in the drying device 10 is air-conveyed to the 2 nd trap part 30B, the 2 nd switching valve 26B is opened, and the

other switching valves

26A, 26C to 26E are closed. When the powder or granular material in the drying device 10 is air-conveyed to the 3 rd trap part 30C, the 3 rd switching valve 26C is opened, and the

other switching valves

26A, 26B, 26D, and 26E are closed. When the powder or granular material in the drying device 10 is air-conveyed to the 4 th trap part 30D, the 4 th switching valve 26D is opened, and the other switching valves 26A to 26C, 26E are closed. When the powder/granular material in the drying device 10 is air-conveyed to the 5 th trap 30E, the 5 th switching valve 26E is opened, and the other switching valves 26A to 26D are closed. In addition, when the secondary conveyance mode is executed, the conveyance air source 20 is in an operating state without being stopped.

By executing this secondary conveyance mode, the particulate material is accumulated in the respective collection units 30A to 30E, and the material request signals of the upper level gauges 33A to 33E and the lower level gauges 34A to 34E of the respective collection units 30A to 30E are lost (material present) (see also fig. 3 (b-1) to 3 (b-5)).

The amount (conveying amount) of the particulate material conveyed by the collection units 30A to 30E may be substantially the same amount, but may be different depending on the processing capacity of the molding machines 6A to 6E, the storage capacity of the collection units 30A to 30E, and the like. The transport amount of the particulate material in the collection sections 30A to 30E may be 2 times or more the storage capacity from the 2 nd level LV2 to the 1 st level LV1 in the collection sections 30A to 30E. The adjustment of the transport amount of the particulate material according to the collection portions 30A to 30E may be performed by adjusting the time (opening time) for which the switching valves 26A to 26E are opened. The conveyance amount in the execution of the secondary conveyance mode in the initial preparation stage (for example, in a state where the level of the powder/granular material accumulated in each of the collection sections 30A to 30E is lower than the level 2 LV 2) may be larger than the conveyance amount in the execution of the secondary conveyance mode in the constant operation stage described later.

If the secondary conveyance mode is executed as described above, the level of accumulation of the powdered or granular material in the drying device 10 is lowered, and a material request signal (no material signal) (absence of a material (full) signal) is output from the conveyance source level meter 15. Therefore, in the present embodiment, the mode is configured to shift to the primary transport mode if the secondary transport mode is ended. That is, the switching valves 26A to 26E and the discharge valve 19 of the transportation target switching valve 25 are closed, the input valve 16 is opened, and the transportation air switching valve 5 is switched to the primary side. The conveyance air source 20 is not stopped and is in an operating state even when the secondary conveyance mode is shifted to the primary conveyance mode. That is, in the present embodiment, the secondary conveyance mode and the primary conveyance mode are continuously performed in a state where the conveyance air source 20 is not stopped and is operating.

Further, if a material (full level) signal is output from the conveyance source level meter 15 of the drying device 10, the primary conveyance mode is ended and the process shifts to the reduced pressure drying mode, as described above.

Further, if the powder/granular material is accumulated in the respective trap portions 30A to 30E, the respective molding machines 6A to 6E are started up to appropriately perform molding preparation steps such as cleaning and trial operation, and a steady operation stage in which the molding steps are sequentially performed is established. If the level of accumulation of the particulate material in the collection portions 30A to 30E is lowered by the execution of the forming process in the forming machines 6A to 6E and predetermined conveyance start conditions are satisfied, the secondary conveyance mode is executed.

In the present embodiment, the structure is: if the accumulated level of the granular material in one of the plurality of collecting sections 30A to 30E is lower than the 1 st level LV1 and the accumulated level of the granular material in the preset number of collecting sections is lower than the 1 st level LV1, the transport start condition (the 1 st transport start condition) is satisfied. The configuration is such that: the 1 st transport start condition is satisfied if the accumulation level of the particulate material in any one of the plurality of collection sections 30A to 30E is not lower than the 2 nd level LV2 and the accumulation levels of the particulate materials in a predetermined number of collection sections are lower than the 1 st level LV1 in a state where the accumulation level of the particulate material in any one of the collection sections is lower than the 1 st level LV 1.

Further, the structure is such that: among the collection portions having a lower level of the particulate matter accumulated than level 1 LV1, the first collection portion that is lower than the first collection portion is set as the collection portion of the priority conveyance target, and the other collection portions are set as the collection portions of the sub-sub conveyance target. Further, the plurality of sub transport target trapping portions are transported in order of being lower than the 1 st level LV 1. Alternatively, instead of this, the order of the conveyance order to the plurality of sub conveyance target collection units may be set in advance.

Further, the structure is such that: in a state where the accumulated level of the particulate material in a certain trap part is lower than the 1 st level LV1, if the accumulated level of the particulate material in all the remaining trap parts is lower than the 1 st level LV1, the 1 st conveyance start condition is satisfied. That is, the number of the trap portions set in advance is set to 4. The number of the preset trap parts is not limited to the remaining total number (4), and may be set to an appropriate number.

In the figure, an example is shown in which, in a state where the level of the accumulated particulate material in the 5 th collection part 30E is lower than the 1 st level LV1, if the level of the accumulated particulate material in all of the remaining collection parts 30A to 30D is lower than the 1 st level LV1, the secondary transport mode is started (see also fig. 4). In the figure, an example is shown in which after the level of accumulation of the particulate material in the 5 th collection part 30E is lower than the 1 st level LV1, if the level of accumulation of the particulate material in the 4 th collection part 30D, the 1 st collection part 30A, and the 2 nd collection part 30B is lower than the 1 st level LV1 and the level of accumulation of the particulate material in the 3 rd collection part 30C is lower than the 1 st level LV1 in this order, the secondary transport mode is started. Further, an example is shown in which after the powder or granular material is transported to the 5 th collection portion 30E as the collection portion targeted for the preferential transport, the powder or granular material is transported to the other collection portions 30A to 30D as the collection portions targeted for the secondary transport. Further, an example is shown in which the powdered or granular material is transported to the collection portion of the secondary transport target in the order of lower level than the 1 st level LV1, that is, in the order of the 4 th collection portion 30D, the 1 st collection portion 30A, the 2 nd collection portion 30B, and the 3 rd collection portion 30C. If the secondary conveyance mode is executed in this way, the primary conveyance mode is executed continuously as described above, and if the primary conveyance mode is ended, the operation is shifted to the reduced-pressure drying mode.

In addition, in the present embodiment, the configuration is such that: in a state where the accumulation level of the particulate material in one of the plurality of collection sections 30A to 30E is lower than the 1 st level LV1, if the accumulation level of the particulate material is lower than the 2 nd level LV2 lower than the 1 st level LV1, the conveyance start condition (the 2 nd conveyance start condition) is satisfied. Further, the structure is such that: in a state where the accumulation level of the particulate material in one of the plurality of collection sections 30A to 30E is lower than the 1 st level LV1, if the accumulation level of the particulate material in a predetermined number (the remaining 4 collection sections in the present embodiment) of collection sections is not lower than the 1 st level LV1 and the accumulation level of the particulate material in the collection section lower than the 1 st level LV1 is lower than the 2 nd level LV2, the 2 nd conveyance start condition is satisfied.

Further, the structure is such that: a collection portion having a level of accumulation of the particulate material lower than the 2 nd level LV2 is set as a collection portion of a priority conveyance target, a collection portion having a level of accumulation of the particulate material lower than the 1 st level LV1 is set as a collection portion of a sub-conveyance target in a state where the level of accumulation of the particulate material in the collection portion of the priority conveyance target is lower than the 2 nd level LV2, and after the second conveyance is performed for the collection portion of the priority conveyance target, the conveyance target is switched to the collection portion of the sub-conveyance target to perform the second conveyance. Further, similarly to the above, the sub-destinations are sequentially transferred to the trapping portion of the sub-destinations in the order lower than the 1 st level LV 1. Alternatively, in the same manner as described above, the order of conveyance to the collection units of the plurality of sub conveyance targets may be set in a predetermined order.

In the figure, an example is shown in which the level of the powder/granular material accumulated in the 5 th collection unit 30E is lower than the 2 nd level LV2, and the secondary conveyance mode is started with the 5 th collection unit 30E as the collection unit targeted for preferential conveyance (see also fig. 5). Further, an example is shown in which the powder and granular material is sequentially transported to the 1 st collecting part 30A and the 4 th collecting part 30D as the collecting parts to be the sub-secondary transport targets having the accumulation level of the powder and granular material lower than the 1 st level LV1 in a state where the accumulation level of the powder and granular material in the 5 th collecting part 30E is lower than the 2 nd level LV 2. In the figure, an example is shown in which the level of accumulation of the particulate material in the other collection portions (the 2 nd collection portion 30B and the 3 rd collection portion 30C) is higher than the 1 st level LV 1. Namely, the structure is as follows: in this secondary transport mode, transport is not performed for the 2 nd trapping portion 30B and the 3 rd trapping portion 30C that are not lower than the 1 st level LV 1.

In the figure, an example is shown in which the 3 rd molding machine 6C as the supply target of the 3 rd collecting portion 30C is stopped before the start of the secondary conveyance mode.

If the secondary conveyance mode is executed in this way, the primary conveyance mode is continuously executed as described above, and if the primary conveyance mode is ended, the operation is shifted to the reduced-pressure drying mode. In the figure, an example is shown in which the 1 st molding machine 6A as a supply target of the 1 st collecting unit 30A and the 5 th molding machine 6E as a supply target of the 5 th collecting unit 30E are temporarily stopped in the reduced pressure drying mode.

Further, an example is shown in which, as the molding is performed in each of the molding machines (molding machines other than the 3 rd molding machine 6C which is stopped in the drawing) 6A to 6E, the level of accumulation of the powder/granular material in the 2 nd collecting portion 30B which is a certain collecting portion is lower than the 2 nd level LV2, and the secondary conveyance mode is started with the 2 nd collecting portion 30B as a collecting portion which is a priority conveyance target (see also fig. 6). Further, an example is shown in which the 5 th collection part 30E and the 4 th collection part 30D, which are collection parts to be sub-secondary transport targets, are sequentially transported with the accumulation level of the particulate material in the 2 nd collection part 30B lower than the 2 nd level LV2, and the accumulation level of the particulate material is lower than the 1 st level LV 1. In the figure, an example is shown in which the level of accumulation of the particulate material in the other collection portions (the 1 st collection portion 30A and the 3 rd collection portion 30C) is higher than the 1 st level LV 1. Namely, the structure is as follows: in this secondary transport mode, transport is not performed for the 1 st trapping part 30A and the 3 rd trapping part 30C which are not lower than the 1 st level LV 1. If the secondary conveyance mode is executed in this way, the primary conveyance mode is executed continuously as described above, and if the primary conveyance mode is ended, the operation shifts to the reduced-pressure drying mode, and then the execution of each mode is executed similarly.

The conveyance amount in the secondary conveyance mode execution performed by the satisfaction of the 1 st conveyance start condition and the conveyance amount in the secondary conveyance mode execution performed by the satisfaction of the 2 nd conveyance start condition may be set to be different amounts. For example, the conveyance amount in the secondary conveyance mode execution performed by the satisfaction of the 1 st conveyance start condition may be smaller than the conveyance amount in the secondary conveyance mode execution performed by the satisfaction of the 2 nd conveyance start condition. Further, the amount of conveyance to the trap portion of the priority conveyance target may be set to be larger than the amount of conveyance to the trap portion of the sub-conveyance target.

According to the transport method of the powder or granular material according to the present embodiment, the transport apparatus 1 of the powder or granular material according to the present embodiment is configured as described above, and thus the number of times of transport is reduced and the retention time of the powder or granular material in the collection portions 30A to 30E can be shortened.

Namely, the structure is as follows: if a predetermined conveyance start condition is satisfied in a state where the accumulation level of a certain collection unit is lower than the 1 st level LV1, the conveyance air source 20 is operated to convey the powdered or granular material to the collection unit of the priority conveyance target, and if a collection unit of the sub-conveyance target lower than the 1 st level LV1 is present in a state where the conveyance start condition is satisfied, the conveyance target is switched to the collection unit of the sub-conveyance target and conveyed. Therefore, if the level is lower than the 1 st level LV1 and the predetermined conveyance start condition is satisfied, the conveyance is preferentially performed to the trap portion of the priority conveyance target, and therefore, it is possible to make it difficult for a shortage of the material (shortage of the material) of the conveyance target and the like to occur.

Further, if the conveyance to the trap unit of the priority conveyance target is finished, the conveyance to the trap unit of the sub-conveyance target is continuously performed, so that the number of times of conveyance can be reduced compared to the case where the conveyance is performed on a level basis for each trap unit. This can reduce the frequent opening and closing of the air supply source 20. In addition, in the case where the drying device 10 is used as the transport source as in the present embodiment, the number of times the outside air flows into the drying device 10 can be reduced. In particular, in the case of the drying apparatus 10 of the reduced pressure type as in the present embodiment, the frequency of destruction (vacuum destruction) of the reduced pressure state can be reduced, and efficient drying can be performed in the drying apparatus 10.

Even when the conveyance to the priority conveyance target is completed and the conveyance to another conveyance target is performed, the conveyance is not performed if the level is lower than the 1 st level LV1, and therefore, the retention time in each of the collection units 30A to 30E can be reduced compared to a configuration in which the collection units on the upstream side are conveyed every time the conveyance is performed. This also enables the collection units 30A to 30E to be downsized.

In addition, in the present embodiment, the configuration is such that: if the accumulated levels of a preset number of trapping portions are lower than the 1 st level LV1, the conveyance start condition (1 st conveyance start condition) is satisfied. Therefore, a predetermined number of trapping portions lower than the 1 st level LV1 can be conveyed. This makes it possible to eliminate the level meter for detecting the 2 nd level LV 2.

In the present embodiment, if the accumulation level of the particulate material is lower than the 2 nd level LV2 lower than the 1 st level LV1, the conveyance start condition (2 nd conveyance start condition) is satisfied. Thus, the 2 nd level LV2 can be conveyed toward the priority conveyance target as the lower limit level. As a result, as compared with the configuration in which the conveyance start condition is set to be lower than the predetermined elapsed time after the 1 st level LV1 as exemplified in embodiment 2 described later, even in the case where the supply targets such as the molding machines 6A to 6E are temporarily stopped, the conveyance start condition at a level lower than the 1 st level LV1 can be detected relatively reliably, and the material shortage (overfeeding) can be suppressed. It is also conceivable that if the transport start condition is set to a predetermined elapsed time, the level of accumulation of the particulate material in the other trap part falls to a level that requires the particulate material within a predetermined time after the level falls below the 1 st level LV1, and the particulate material becomes insufficient.

Next, an example of a method for conveying a powder or granular material according to embodiment 2, which is another embodiment of the present invention, will be described with reference to fig. 7.

The differences from embodiment 1 will be mainly described, and the same operations as those in the above-described operation example will be omitted or briefly described.

In the present embodiment, the configuration is such that: when the level of the particulate material accumulated in any one of the plurality of collection units 30A to 30E is lower than the 1 st level LV1, the conveyance start condition (the 3 rd conveyance start condition) is satisfied if the predetermined 1 st time t1 has not elapsed and the level of the particulate material accumulated in a predetermined number of collection units is lower than the 1 st level LV 1. The 3 rd conveyance start condition detection unit that detects the 3 rd conveyance start condition may be the control unit 36 as described above.

In addition, in the present embodiment, the configuration is such that: if a predetermined 1 st time t1 elapses after the accumulation level of the particulate material becomes lower than the 1 st level LV1, the conveyance start condition (4 th conveyance start condition) is satisfied. Further, the structure is such that: after the accumulation level of the particulate material is lower than the 1 st level LV1, if the accumulation level of the particulate material in the predetermined number of trapping portions is not lower than the 1 st level LV1 and a predetermined 1 st time t1 elapses, the 4 th conveyance start condition is satisfied. In other words, in the present embodiment, if the predetermined 1 st time t1 elapses after the level is lower than the 1 st level LV1, it is assumed that the level is lower than the 2 nd level LV 2.

The 4 th conveyance start condition detection unit that detects the 4 th conveyance start condition may be a control unit 36 having a timer unit (timer). The predetermined 1 st time t1 may be set to an appropriate time so as not to cause shortage of the material, depending on the storage capacity of each of the trap portions 30A to 30E, the processing capacity of each of the molding machines 6A to 6E, and the like.

Further, the powder or granular material conveying apparatus 1 (see fig. 1) used for the method of conveying a powder or granular material according to the present embodiment may be configured to: instead of providing the upper level meters 33A to 33E and the lower level meters 34A to 34E for detecting the 1 st level LV1 and the 2 nd level LV2 in the respective trapping units 30A to 30E (see fig. 1), the trapping level meters 39A to 39E as the 1 st level detecting unit for detecting the 1 st level LV1 are provided.

In the present embodiment, as described above, in the initial preparation stage, a primary transport mode of transporting the powder/granular material to the drying device 10, a reduced-pressure drying mode of drying the powder/granular material in the drying device 10, a secondary transport mode of transporting the powder/granular material to the collection units 30A to 30E, and a primary transport mode of transporting the powder/granular material to the drying device 10 whose accumulation level has decreased due to the execution of the secondary transport mode are executed. Further, if the powder/granular material is conveyed to each of the collection units 30A to 30E, the powder/granular material is formed by the forming machines 6A to 6E that are the supply targets of the collection units 30A to 30E, and the level of accumulation of the powder/granular material in the collection units 30A to 30E is lowered.

Further, substantially the same as above, the configuration is such that: if the predetermined 1 st time t1 does not elapse after the accumulation level of the particulate material in a certain collection portion (in the figure, the 5 th collection portion 30E) is lower than the 1 st level LV1, and the accumulation level of the particulate material in all the other collection portions (in the figure, the 1 st collection portion 30A to the 4 th collection portion 30D) is lower than the 1 st level LV1, the secondary conveyance mode is started. Further, if the secondary conveyance mode is ended, the primary conveyance mode is continuously executed as described above, and if the primary conveyance mode is ended, the operation is shifted to the reduced pressure drying mode.

Further, the configuration is: after the accumulation level of the particulate material in one of the plurality of collection sections 30A to 30E (in the figure, the 5 th collection section 30E) is lower than the 1 st level LV1, if the accumulation level of the particulate material in none of the predetermined number of collection sections (in the present embodiment, all the remaining collection sections) is lower than the 1 st level LV1 and the 1 st time t1 elapses, the secondary conveyance is performed with the collection section lower than the 1 st level LV1 (in the figure, the 5 th collection section 30E) as the collection section of the priority conveyance target. Further, the structure is such that: in a state where the 1 st time t1 has elapsed, the transport target is switched to the collection section (in the illustration, the 1 st collection section 30A and the 4 th collection section 30D) of the sub-transport target in which the accumulated level of the granular material is lower than the 1 st level LV1, and the secondary transport is performed. If the secondary conveyance mode is executed in this way, the primary conveyance mode is continuously executed as described above, and if the primary conveyance mode is ended, the vacuum drying mode is shifted to, and then the modes are executed similarly.

The method for conveying a powder or granular material according to the present embodiment having the above-described configuration also achieves substantially the same effects as those of embodiment 1.

In addition, in the present embodiment, the configuration is such that: if a predetermined 1 st time t1 elapses after the accumulation level of the particulate material becomes lower than the 1 st level LV1, the conveyance start condition (4 th conveyance start condition) is satisfied. Therefore, a level meter capable of detecting the 2 nd level LV2 in addition to the 1 st level LV1 may not be provided, and the device configuration can be simplified.

In the above embodiments, the example in which the upper level meters 33A to 33E or the trap level meters 39A to 39E outputting the request signal are provided as the 1 st level detecting unit for detecting the 1 st level LV1 is shown, but the present invention is not limited to this embodiment. The following may be adopted: the upper level meters 33A to 33E or the trap level meters 39A to 39E are level meters that output a full cup signal as a trigger signal for stopping the conveyance, and if a predetermined time has elapsed since the full detection by the level meters, it is determined that the level is lower than the 1 st level LV 1. That is, instead of the mode in which the 1 st level LV1 is detected directly by the level meter, it may be determined that the level is less than the 1 st level LV1 in an estimated manner if a predetermined time has elapsed from the detection by the level meter. In this case, the predetermined time may be set as appropriate in accordance with the processing capacity of each of the molding machines 6A to 6E. In this case, the control unit 36 having a timer unit (timer) may constitute the 1 st level detection unit.

Further, as the conveyance start conditions for executing the secondary conveyance mode, the 1 st conveyance start condition and the 2 nd conveyance start condition are exemplified in the above-described embodiment 1, and the 3 rd conveyance start condition and the 4 th conveyance start condition are exemplified in the above-described embodiment 2, but at least one of these 1 st conveyance start condition to 4 th conveyance start condition may be used, and other conveyance start conditions may be used.

The supply source 10 is not limited to the above-described reduced pressure type drying apparatus 10, and may be other drying apparatuses, or may be various supply sources such as a mixing apparatus, a material tank, or the like, without being limited to the drying apparatus.

In the above-described embodiment, an example in which a plurality of transfer lines 23A to 23E branched into a plurality from a single material transfer line 21 connected to the discharge side of the transfer source 10 via a branching portion 22 are connected to the respective trap portions 30A to 30E has been described, but the present invention is not limited to this embodiment. For example, the conveyance lines 23A to 23E connected to the respective trap portions 30A to 30E may be connected to the discharge side of the conveyance source 10. The configuration is not limited to the configuration having 5 collecting units 30A to 30E as illustrated in the figure, and may be a configuration having 2 or more collecting units. The air supply source 20 is not limited to a suction air box for sucking and conveying the powder or granular material, and may be a compressed air source for pressure-feeding the powder or granular material. The method for conveying the powder or granular material and the apparatus 1 for conveying the powder or granular material according to the above embodiments are not limited to the above-described configurations, and various modifications may be made thereto.

Claims

1. A method for transporting a powder or granular material, wherein the powder or granular material as a transport source is air-transported by switching the transport source among a plurality of collection units,

if the level of the powder/granular material accumulated in any one of the plurality of collecting units is lower than the 1 st level and the level of the powder/granular material accumulated in the collecting unit is lower than the 2 nd level lower than the 1 st level, the transportation air source is operated to transport the powder/granular material to the collecting unit lower than the 2 nd level that is the priority transport target, and if a collecting unit that is a secondary transport target lower than the 1 st level is present in the state where the collecting unit of the priority transport target is lower than the 2 nd level, the transport target is switched to the collecting unit of the secondary transport target and transported without being transported to the collecting unit lower than the 1 st level.

2. The method for transporting a powdered or granular material according to claim 1,

and a determination that the level of the powder/granular material accumulated in any one of the plurality of collecting parts is lower than the 1 st level and a predetermined 1 st time elapses after the level is lower than the 1 st level.

3. The method for transporting a powdered or granular material according to claim 1 or 2,

when the accumulation level of the particulate material in any one of the plurality of collection units is lower than the 1 st level, the accumulation level in any one of the collection units is not lower than the 2 nd level, and further, the accumulation levels in a predetermined number of collection units are lower than the 1 st level, the transport air source is operated to transport the particulate material to the collection unit that is the priority transport target lower than the 1 st level first, and the transport target is switched to and transported to the collection unit that is the other sub-transport target lower than the 1 st level, without being transported to the collection unit that is not lower than the 1 st level.

4. A powder and granular material conveying device for switching a conveying source of powder and granular material to a plurality of collecting parts to perform air conveyance, the device comprising:

a 1 st level detection unit that detects a 1 st level as a level of accumulation of the particulate material in each of the plurality of collection units;

a 2 nd level detecting unit configured to detect a 2 nd level lower than the 1 st level as a level of accumulation of the particulate material in each of the plurality of collecting units; and

and a control unit that, if it is detected that the accumulation level of any one of the plurality of collection units is lower than the 1 st level and the accumulation level of the collection unit is lower than the 2 nd level, operates the conveyance air source to convey the particulate material to a collection unit that is a priority conveyance target and is lower than the 2 nd level, and if it is detected that a collection unit that is a secondary conveyance target and is lower than the 1 st level is lower than the 2 nd level and the collection unit that is the primary conveyance target is lower than the 1 st level, performs control such that the conveyance target is switched to the collection unit of the secondary conveyance target and is not conveyed to a collection unit that is not lower than the 1 st level.

5. The apparatus for transporting powdered or granular material according to claim 4,

the control unit operates the transportation air source to convey the particulate material to the collection unit that is the priority conveyance target lower than the 1 st level first, and switches and conveys the conveyance target to the collection unit that is the other sub-conveyance target lower than the 1 st level, without conveying the particulate material to the collection unit that is not lower than the 1 st level, when it is detected that the accumulation level of any one of the collection units is lower than the 1 st level, and it is further detected that the accumulation levels of a predetermined number of collection units are lower than the 1 st level.