Specific volume measurement system and specific volume calculation method

Abstract

To provide a technique capable of automatically measuring the specific volume of powder during processing.SOLUTION: A specific volume measurement system includes: a powder feeder that continuously discharges powder of a specified volume from the discharge port based on a cross-sectional area formed of an upper surface of an outer peripheral edge, a peripheral wall surface of a peripheral wall, a lower surface of a partition plate, and a side surface of a cylindrical body and the number of concentric rotations; and a control unit that is configured to operate the powder feeder under the condition that at least, an inclination angle of an agitator blade to a horizontal plane is set according to physical characteristics of the powder and the agitator and a feed plate rotate at the same rotation speed, calculate a differential weight value, which is the difference between two weight values acquired at periodic intervals via a weight sensor, and calculate a specific volume of the powder based on the differential weight value, a unit volume of the powder discharged from the discharge port of the powder feeder per unit rotation of the feed plate, and the number of rotations in a given periodic interval.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a specific volume measuring system capable of measuring the specific volume of powder or granular material and a specific volume calculation method. [Background technology]

[0002] Conventionally, in the manufacturing process of powders and granules (hereinafter also referred to as powders and granules), the specific volume (volume (ml) occupied by unit mass (g), also referred to as specific volume) of various powders and granules to be manufactured is managed. For example, the specific volume is measured by sampling powders and granules from a manufacturing line where a powder feeder or the like disclosed in Patent Document 1 is installed, and measuring using a dedicated specific volume meter (e.g., bulk density measuring instrument, etc.) that complies with JIS standards. When sampling powder from the manufacturing line, there are problems depending on the situation of the factory, such as temporarily stopping the equipment (causing a decrease in production capacity) and opening the system to sample with a scoop or the like (risk of foreign matter, workload, etc.). In addition, since the specific volume meter measures data manually, there are various problems, such as variations in measured values ​​depending on the operator, and the measurement values ​​cannot be automatically analyzed and fed back to the manufacturing conditions, so changes to the manufacturing conditions depend on human judgment. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6137826 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a technique capable of automatically measuring the specific volume of powder or granular material during processing. [Means for solving the problem]

[0005] The inventors of the present invention have conducted extensive research and found that the powder feeder can solve the above problems by adopting the following configuration. That is, the powder feeder of the specific volume measurement system according to one embodiment includes an upper reservoir that stores a predetermined amount of powder and granular material supplied and sends out the stored powder and granular material from a delivery port, and a lower reservoir that contains the powder and granular material sent out from the upper reservoir. A receiver is disposed below the lower reservoir as the bottom of the lower reservoir, and has a bottom surface and a peripheral wall portion connected to the bottom surface, the peripheral wall portion having a discharge port formed therein for discharging the powder and granular material, and an agitator is provided that rotates within the lower reservoir and agitates the powder and granular material contained in the lower reservoir. A supply plate is provided between the lower reservoir and the receiver, parallel to the bottom of the receiver, that rotates concentrically with the agitator within the receiver, and that has a flow path formed therein for transporting the powder and granular material agitated by the agitator and introducing it into the discharge port of the receiver. The supply plate is configured to include an outer peripheral edge formed in a flange shape of a predetermined width from the outer periphery, and a cylindrical body that forms a step with respect to the upper surface of the outer peripheral edge inside the outer peripheral edge. The receiver is provided with a partition plate parallel to the supply plate above the supply plate, which aligns the powder and granular material on the supply plate to a predetermined height, and a deflection plate that deflects the powder and granular material transferred on the outer peripheral edge in the rotation direction of the supply plate toward the outside of the outer periphery of the supply plate. The supply plate continuously discharges a predetermined volume of powder and granular material from the discharge port according to the cross-sectional area (rectangular area) formed by the upper surface of the outer peripheral edge, the peripheral wall surface of the peripheral wall, the lower surface of the partition plate, and the side surface of the cylindrical body, and the number of concentric rotations. The control unit of the specific volume measurement system according to one embodiment operates the powder feeder under conditions of at least the inclination angle of the agitator blade with respect to the horizontal plane set according to the physical characteristics of the powder and granular material, and the same rotation speed at which the agitator and the feeder plate rotate. The control unit acquires the weight value of the powder feeder measured via the weight sensor at a predetermined periodic interval, obtains a differential weight value that is the difference between two weight values ​​acquired before and after the predetermined periodic interval, and calculates the differential weight value and The specific volume of the powder or granule is calculated based on the unit volume value of the powder or granule discharged from the discharge port of the powder feeder per unit rotation of the feed plate and the number of rotations in a predetermined periodic interval.

[0006] A more detailed configuration is as follows. [1] an upper reservoir that stores a predetermined amount of the supplied powder or granular material and delivers the stored powder or granular material from a delivery port; a lower reservoir for accommodating the powder or granular material discharged from the upper reservoir; a receiver connected to the lower part of the lower reservoir as a bottom of the lower reservoir, the receiver having a bottom surface and a peripheral wall portion connected to the bottom surface and having a discharge port formed in a part of the peripheral wall for discharging the powder or granular material; an agitator that rotates within the lower reservoir and agitates the powder and granular material contained in the lower reservoir; a supply plate provided between the lower reservoir and the receiver in parallel with the bottom of the receiver, rotating concentrically with the agitator in the receiver, and having a flow path formed thereon for transporting the powder and granular material agitated by the agitator and introducing the powder and granular material into the discharge port of the receiver; The supply plate includes an outer peripheral edge portion formed in a flange shape having a predetermined width from an outer periphery, and a cylindrical body that forms a step with respect to an upper surface of the outer peripheral edge portion on the inside of the outer peripheral edge portion, The receiver is provided with a partition plate above the supply plate and parallel to the supply plate, for aligning the powder on the supply plate to a predetermined height, and a deflection plate for deflecting the powder transferred on the outer periphery of the supply plate in the rotation direction, toward the outside of the outer periphery of the supply plate; the supply plate continuously discharges from the discharge port a predetermined volume of powder or granular material according to a cross-sectional area formed by an upper surface of the outer periphery portion, a peripheral wall surface of the peripheral wall portion, a lower surface of the partition plate, and a side surface of the cylindrical body, and according to the number of rotations of the concentric rotation; a weight sensor that measures the weight of the powder feeder to which a predetermined amount of powder or granular material has been fed and outputs a signal corresponding to the measured weight; A counting sensor that counts the number of rotations of a supply plate of the powder supplying machine; The powder feeder is operated under conditions that the inclination angle of the stirring blade of the stirring body with respect to a horizontal plane is set according to at least the physical characteristics of the powder and that the stirring body and the supply plate rotate at the same rotation speed; a control unit that acquires a weight value of the powder feeder measured via the weight sensor at a predetermined periodic interval, determines a differential weight value that is a difference between two weight values ​​acquired before and after the predetermined periodic interval, and calculates a specific volume of the powder or granular material based on the differential weight value, a unit volume value of the powder or granular material discharged from an outlet of the powder feeder per unit rotation of the supply plate, and the number of rotations at the predetermined periodic interval; A specific volume measurement system comprising: [2] The control unit operates the powder feeder under conditions where the compression rate of the powder or granular material is 2 percent or less, the inclination angle of the agitating blade with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm, and calculates the specific volume by making corrections based on at least one correction amount of the amount of loss of the powder or granular material supplied to the powder feeder that cannot reach the discharge outlet and the powder pressure. [3] The control unit operates the powder feeder under the conditions that the compression rate of the powder or granular material is 3 percent or less, the inclination angle of the agitator blade with respect to the horizontal plane is in the range of 45 degrees or more and less than 135 degrees, and the rotation speed is in the range of 3 rpm to 9 rpm. [4] The control unit operates the powder feeder under the conditions that the compression rate of the powder is less than 4.1%, the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 45 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm, and The specific volume measuring system according to [1], wherein the specific volume is calculated by performing a correction based on at least one correction amount of a loss amount of the powder or granular material supplied to the discharge port that cannot reach the discharge port and a powder pressure. [5] The control unit operates the powder feeder under conditions that the inclination angle of the agitator blade with respect to the horizontal plane is in the range of more than 45 degrees to 180 degrees and the rotation speed is in the range of 3 rpm to 12 rpm, and calculates the specific volume by making a correction based on the amount of loss of the powder or granular material supplied to the powder feeder that cannot reach the discharge outlet. [6] The control unit operates the powder feeder under conditions that the inclination angle of the agitator blade with respect to the horizontal plane is in the range of 45 degrees to 180 degrees and the rotation speed is in the range of 3 rpm to 12 rpm. [7] The control unit operates the powder feeder under the conditions that the compression rate of the powder or granular material is less than 4.3 percent, the inclination angle of the agitator blade with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm. [8] The control unit operates the powder feeder under conditions where the compression rate of the powder or granular material is 9.8 percent to 17.2 percent, the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 90 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm, and calculates the specific volume by correcting the powder pressure of the powder or granular material supplied to the powder feeder. [9] The control unit operates the powder feeder under the conditions that, when the compression rate of the powder or granular material exceeds 24.3 percent, the inclination angle of the stirring blade with respect to the horizontal plane is more than 45 degrees and less than 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm, and calculates the specific volume by correcting the powder pressure of the powder or granular material supplied to the powder feeder.

[10] The control unit sets an upper limit weight and a lower limit weight at which the powdered or granular material supplied to the powder feeder is stored in an upper reservoir, detects when the weight value of the powder feeder measured by the weight sensor falls below the lower limit weight, and supplies an amount of powdered or granular material not exceeding the upper limit weight to the upper reservoir.The specific volume measuring system described in [1].

[11] The control unit acquires the weight value of the powder supplying machine measured via the weight sensor at a predetermined number of rotations of the supply plate, which is set in advance, after a certain period of time has elapsed since a predetermined amount of powder or granular material was supplied to the upper reservoir.

[12] The control unit corrects the calculated specific volume based on the amount of powder or granular material lost when a portion of the powder or granular material passing through the cross-sectional area flows out of the gap between the upper surface of the outer peripheral edge portion and the lower end of the deflection plate and thus cannot reach the discharge outlet.

[13] The control unit corrects the calculated specific volume based on the compressibility of the powder or granular material for powder or granular material having a compressibility of 4 or more.

[14] A storage body having a cylindrical inner space for temporarily storing the powder and granular material flowing therein; The cylindrical inner space rotates around the central axis, and the powder temporarily stored in the storage body is rotated around the central axis, so that the powder temporarily stored in the storage body is discharged from the discharge port. A powder feeder having a discharge mechanism for discharging the powder, and a weight sensor that measures a weight value of the powder feeder in which the powder or granular material is temporarily stored; A counting sensor that counts the number of rotations; a control unit that calculates a specific volume of the powder or granular material based on a differential weight value that is a difference between the weight values ​​acquired at a predetermined periodic interval and the number of rotations at the predetermined periodic interval; A specific volume measurement system comprising:

[15] A specific volume calculation method comprising the steps of: operating a powder feeder having a discharge mechanism that rotates around the central axis of a cylindrical inner space of a storage body that temporarily stores powder and granular material, and discharges the powder and granular material temporarily stored in an upper storage body connected above the storage body from a discharge outlet by rotating and moving the powder and granular material temporarily stored in the upper storage body about the central axis, under conditions of an inclination angle of the agitator blade of an agitator body with respect to a horizontal plane that is set in accordance with the physical characteristics of the powder and granular material, and an identical rotational speed at which the agitator body and the supply plate of the discharge mechanism rotate; acquiring weight values ​​of the powder feeder at predetermined periodic intervals, and calculating a specific volume of the powder and granular material based on a differential weight value that is the difference between the weight values ​​acquired at the predetermined periodic intervals and the number of rotations at the predetermined periodic interval.

[16]

[17] The method for calculating a specific volume according to

[15] , further comprising correcting the calculated specific volume based on a loss amount of the powder or granular material remaining in a receiver connected below the reservoir and unable to reach the discharge outlet. The method for calculating a specific volume according to

[15] , further comprising correcting the calculated specific volume based on the compressibility of the powder or granular material for a powder or granular material having a compressibility of 4 or more. Effect of the Invention

[0007] According to the present invention, a technique can be provided that can automatically measure the specific volume of powder or granular material during processing. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic cross-sectional side view showing one example of a powder feeder according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view taken along lines AA and BB shown in FIG. [Diagram 3] FIG. 3 is an exploded perspective view of the powder feeder according to the embodiment. [Figure 4] FIG. 4 is a perspective view illustrating the structure of the supply board according to the embodiment. [Diagram 5] FIG. 5 is a diagram illustrating flow paths formed in a supply board according to the embodiment. [Figure 6]FIG. 6 is a diagram illustrating a deflection plate provided on a receiver according to the embodiment. [Figure 7] FIG. 7 is a diagram illustrating the structure of the stirrer according to the embodiment. [Figure 8] FIG. 8 is a side view illustrating the relative angle of the stirring blade according to the embodiment with respect to the horizontal plane. [Figure 9] FIG. 9 is a diagram illustrating the stirring of powder or granular material by the stirrer according to the embodiment. [Figure 10] FIG. 10 is a diagram showing an example of the configuration of a specific volume measuring system according to an embodiment. [Figure 11] FIG. 11 is a diagram showing the measurement results in the first embodiment. [Figure 12] FIG. 12 is a diagram showing the measurement results in the second embodiment. [Figure 13] FIG. 13 is a diagram showing the measurement results in the third embodiment. [Figure 14] FIG. 14 is a diagram showing the measurement results in the fourth embodiment. [Figure 15] FIG. 15 is a diagram showing the measurement results in the fifth embodiment. [Figure 16] FIG. 16 is a diagram showing the measurement results in the sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, one embodiment of the present invention will be described with reference to the drawings. The following describes a powder feeder according to the present invention (also referred to as a powder feeder having a powder feeder with ...

[0010] (Powder feeder configuration) First, the powder feeder 1 according to the present embodiment will be described. FIG. 1 is a schematic cross-sectional side view showing one example of the powder feeder 1 according to the present embodiment. FIG. 2(a) and FIG. 2(b) are cross-sectional views along the line AA and the line BB shown in FIG. 1, respectively. FIG. 3 is an exploded perspective view of the powder feeder 1 according to the present embodiment. As shown in FIG. 1 to FIG. 3, the powder feeder 1 includes an upper reservoir 10 for storing a predetermined amount of powder and granular material supplied from an upstream process, a lower reservoir 13 connected to the lower side of the upper reservoir 10, and a receiver 16 connected to the lower side of the lower reservoir 13 as the bottom of the lower reservoir 13. A storage case 31 in which a rotation drive mechanism is stored is connected to the lower side of the receiver 16 via a lifting platform 32. The rotation drive mechanism is, for example, interlocked with a drive shaft of an electric motor or the like, and drives a vertical shaft 30, which is a rotating shaft member extending to the upper reservoir 10, at a predetermined rotation speed (rpm). A vertical shaft 30 is inserted through the approximate center of each of the upper reservoir 10, the lower reservoir 13, and the receiver 16, so as to be concentric with each other. The vertical shaft 30 is configured to be rotatable within the powder feeder.

[0011] The upper reservoir 10 has a cylindrical shape, and as shown in the cross-sectional view of line AA in FIG. 2(a), a pressure adjusting plate 12 having a plurality of outlets 12a is provided at the bottom. An insertion hole 12b through which a vertical shaft 30 is inserted is provided at the center of the pressure adjusting plate 12. The upper reservoir 10 is provided with an agitator blade 11 having a horizontal cross section extending in the radial direction and substantially dogleg-shaped (or angle bracket-shaped). The agitator blade 11 is fixed to the upper surface side of the pressure adjustment plate 12 in the vertical direction via an end plate 11a (FIG. 3) at the end of the vertical shaft 30 inserted through the insertion hole 12b. In the upper reservoir, the agitator blade 11 rotates counterclockwise (the rotation direction in which the center point of rotation with respect to the direction of travel is on the left side) as shown by the solid arrow Z1 (FIG. 2) when viewed from the top of the pressure adjustment plate 12. The powder and granular material supplied to the upper reservoir 10 is delivered to the lower reservoir 13 through the multiple delivery ports 12a by the rotation of the agitator blade 11 journaled on the vertical shaft 30. The pressure adjustment plate 12 provided at the bottom suppresses fluctuations in the amount of powder delivered from the delivery port 12a to the lower reservoir 13.

[0012] The lower reservoir 13 has a cylindrical shape with a smaller diameter than the upper reservoir 10, and stores the powdered or granular material discharged from the upper reservoir 10 through the multiple discharge ports 12a. The lower reservoir 13 is provided with an agitator 14 that is supported by a vertical shaft 30 and can rotate concentrically in the inner space of the lower reservoir. The agitator 14 has a conical or truncated conical base and multiple agitator blades 14a extending from the inclined surface of the base in the radial direction of the lower reservoir 13. The agitator blades 14a are provided at equal intervals (equal angular intervals with respect to the central axis of the vertical shaft 30) around the circumferential direction of the base. In the inner space of the lower reservoir 13, the agitator 14 rotates counterclockwise (a rotation direction in which the center point of rotation with respect to the direction of travel is on the left side) around the vertical shaft 30, which is the central axis, when viewed from the upper reservoir side, and agitates the stored powdered or granular material.

[0013] The receiver 16 is a substantially bucket-shaped container connected to the lower side of the lower reservoir 13 as the bottom of the lower reservoir. The receiver 16 has a bottom surface 16a and a peripheral wall portion 16b (FIG. 3) in which a discharge port 19 for discharging powder and granular material is formed in a partial area of ​​the peripheral wall connected to the bottom surface, and is configured to be able to accommodate a supply board 20. An insertion hole 16c through which a vertical shaft 30 is inserted is opened in the center of the bottom surface 16a of the receiver 16 (FIG. 3). A flat partition plate 15 is provided between the peripheral wall portion 16b in which the discharge port 19 of the receiver 16 is formed and the lower surface of the stirring blade 14a so that the powder and granular material stirred by the stirring body 14 does not flow into the discharge port 19, as shown in the BB line cross-sectional view of FIG. 2(b).

[0014] The partition plate 15 is provided, for example, so as to include an area where the discharge port 19 is formed and to cover a sector-shaped area below between the agitating blades provided at equal intervals in the circumferential direction of the base constituting the agitator 14. The agitating blades 14a rotate in the space area above the partition plate 15 and the supply plate 20 housed in the receiver 16. In addition, a fixed blade 17 is provided on the upper surface of the peripheral wall portion 16b of the receiver 16 to scrape out powder particles that have entered the gap between the agitating blades 14a and the upper surface of the supply plate 20.

[0015] The supply platen 20 is provided between the lower reservoir 13 and the receiver 16, parallel to the bottom surface 16a of the receiver 16. The supply platen 20 is supported by a vertical shaft 30 and configured to be rotatable concentrically with the agitator 14 within the receiver. A flow path is formed in the supply platen 20 to transport the powdered material agitated by the agitator 14 and introduce it into a discharge port 19 provided in the peripheral wall 16b of the receiver 16.

[0016] (Supply panel structure) Next, the structure of the supply board 20 will be described. FIG. 4 is a perspective view illustrating the structure of the supply board 20. FIG. 4(a) is a perspective view of the supply board 20, and FIG. 4(b) is a perspective view illustrating the arrangement of the supply board 20 and the partition plate 15 provided on the receiver 16. As shown in FIG. 4(a), the supply board 20 is substantially disk-shaped, and includes an outer peripheral edge portion 20a formed in a brim shape of a predetermined width from the outer periphery, and a cylindrical body 20b that forms a step with respect to the vertical upper surface of the outer peripheral edge portion 20a inside the outer peripheral edge portion 20a. An insertion structure 20c is formed in the center of the cylindrical body 20b, through which the vertical shaft 30 is inserted and which supports the supply board. The insertion structure 20c is cylindrical, and an engagement groove is provided on the inner wall surface for supporting the inserted vertical shaft 30. The supply platen 20 is supported by a vertical shaft 30 inserted into the insertion structure 20c, and rotates concentrically with the agitator 14 at the same rotational speed.

[0017] A plurality of flat-shaped ring body scraping wings 21 extending radially to the vicinity of the peripheral wall surface of the receiver 16 are provided on the outer edge portion (hereinafter referred to as the outer edge upper surface) of the upper surface of the cylindrical body 20b close to the side surface. In the embodiment shown in Figs. 4(a) and (b), six ring body scraping wings 21 are provided, and each ring body scraping wing is provided in the circumferential direction of the cylindrical body 20b at equal intervals of approximately 60 degrees with respect to the central axis of the insertion structure 20c. The height position of the outer edge side upper surface of the cylindrical body 20b from the upper surface of the outer peripheral edge portion 20a and the height position of the upper surface of the plurality of ring body scraping wings 21 provided are configured to be approximately the same height position. That is, the ring body scraping wings 21 are provided by being fitted into the cylindrical body 20b on the upper surface of the cylindrical body 20b.

[0018] 4(b), the partition plate 15 provided on the upper surface of the peripheral wall portion 16b of the receiver 16 is disposed above the supply plate 20 in parallel with the upper surface of the outer peripheral edge portion 20a formed in a brim shape of the supply plate 20. The lower surface of the partition plate 15 is disposed at approximately the same height as the upper surface of the outer edge side of the cylindrical body 20b on which the multiple ring-shaped scraping blades 21 are provided.

[0019] Fig. 5 is a diagram illustrating the flow paths formed in the supply plate 20. Fig. 5 shows a partial perspective view of the outer peripheral edge portion 20a and the cylindrical body 20b that constitute the supply plate 20. As shown in a rectangular area Z2 in Fig. 5, the flow paths formed in the supply plate 20 are configured to have a substantially rectangular cross-sectional area formed by a brim-shaped predetermined width D1 of the outer peripheral edge portion 20a and a height D2 between the upper surface of the outer peripheral edge portion 20a and the lower surface of the partition plate 15.

[0020] When accommodated in the receiver 16, the outer periphery of the supply platen 20 is substantially the same as the inner periphery of the peripheral wall portion 16b of the receiver 16. The flow path formed in the supply platen 20 is an annular groove flow path between the receiver 16 and the supply platen 20, the outer periphery of which is surrounded by the peripheral wall surface of the peripheral wall portion 16b, and which is constituted by the upper surface of the outer periphery edge portion 20a and the wall surface (side surface) of the cylindrical body 20b. The supply platen 20 is supported by a vertical shaft 30 inserted through the insertion structure 20c, and rotates in the counterclockwise direction indicated by the arrow Z3.

[0021] The powder particles stirred by the stirrer 14 in the lower reservoir 13 flow down into the flow path of the annular groove surrounded by the peripheral wall surface of the peripheral wall portion 16b, and are transferred to the discharge port 19 provided in the peripheral wall portion 16b of the receiver 16 as the supply plate 20 rotates. As shown in FIG. 2(b), a partition plate 15 is provided in the fan-shaped area including the discharge port 19. As shown in FIG. 4(b), the partition plate 15 is provided above the supply plate 20. Therefore, the powder particles on the supply plate transferred as the supply plate 20 rotates are aligned to a predetermined height (height D2 between the upper surface of the outer peripheral edge portion 20a and the lower surface of the partition plate 15) by the lower surface of the partition plate 15, and are introduced into the discharge port 19 in a state having a cross-sectional area of ​​a rectangular area Z2. The ring scraping blade 21 functions as a member that scrapes off the powder particles adhering to the lower surface of the partition plate 15 when passing over the lower surface of the partition plate 15.

[0022] The receiver 16 is provided with a deflector plate 18 that deflects the powder or granular material transferred on the outer peripheral edge in the direction of rotation as the supply plate 20 rotates, toward the outside of the outer periphery of the supply plate 20. The deflector plate 18 is provided near the discharge port as shown in Fig. 3. The powder or granular material having a predetermined cross-sectional area (rectangular area Z2) transferred by the rotation of the supply plate 20 is deflected by the deflector plate 18 provided near the discharge port, as shown by arrow Z4, and is discharged from the discharge port 19.

[0023] As a result, supply plate 20 can continuously discharge a predetermined volume of powder from outlet 19 according to the cross-sectional area formed by the upper surface of outer circumferential edge portion 20a, the peripheral wall surface of peripheral wall portion 16b, the lower surface of partition plate 15, and the side surface of cylindrical body 20b, and the number of rotations of supply plate 20. In powder supply device 1 according to this embodiment, powder can be discharged while rotating in a predetermined cross-sectional area, so that by setting the rotation speed (rpm) of supply plate 20 in advance, it is possible to grasp the unit volume value, which is the volumetric flow rate per unit time.

[0024] As shown in Fig. 5, a knurling process 20d is applied to the upper surface of the outer peripheral edge 20a of the supply plate 20 and the side surface of the cylindrical body 20b. By applying the knurling process 20d, it is possible to increase the retention force in the flow path on the supply plate when the powder or granular material flowing down by the rotation of the agitator 14 is placed and transferred to the discharge port 19. Even if the powder or granular material to be processed has different properties such as particle size, flowability, and cohesiveness, it is possible to improve the retention force for transferring the powder or granular material to the discharge port 19 while maintaining a predetermined cross-sectional area.

[0025] FIG. 6 is a diagram for explaining the deflection plate 18 provided on the receiver 16. In FIG. 6, a partial perspective view of the supply board 20 accommodated in the receiver 16 is shown with the partition plate 15 provided near the discharge port 19 removed. As shown in FIG. 6, in the receiver 16, the deflection plate 18 is provided on the front end side of the discharge port 19 with respect to the rotation direction of the supply board 20 so as to block the flow path on the supply board. In addition, the multiple fixed blades 17 provided on the receiver 16 function as members that scrape off the powder particles attached to the upper surface of the cylindrical body 20b on which the rotary body scraping blade 21 of the supply board 20 is provided, into the flow path. The rotary body scraping blade 21 provided on the supply board 20 and the fixed blades 17 provided on the receiver 16 can suppress the amount of powder particles remaining during operation of the powder feeder 1.

[0026] (Agitator structure) Next, the structure of the agitator 14 will be described. FIG. 7 is a diagram for explaining the structure of the agitator 14. FIG. 7(a) shows a top view of the agitator 14, and FIG. 7(b) shows a side view of the agitator 14. As shown in FIG. 7(a) and (b), the agitator 14 is configured to include a conical or truncated conical base 14b and a plurality of agitator blades 14a extending radially from the inclined surface of the base 14b. An insertion structure 14c is formed in the upper center of the base 14b, through which the vertical shaft 30 is inserted and which supports the agitator. The insertion structure 14c is cylindrical, and an engagement groove is provided on the inner wall surface for supporting the inserted vertical shaft 30. The agitator 14 is supported by the vertical shaft 30 inserted into the insertion structure 14c, and rotates at the same rotation speed in a concentric state with the base 14b and the agitator blades 14a. The agitator 14 rotates at the same rotation speed as the supply platen 20, with the vertical shaft 30 as the same axis.

[0027] The stirring blades 14a are provided on the lower side of the base 14b at equal intervals in the circumferential direction of the base 14b. In the embodiment shown in Figures 7(a) and (b), three stirring blades 14a are provided, and each stirring blade is provided at 120 degree intervals in the circumferential direction of the base 14b. The cross-sectional shape of the stirring blade 14a is approximately rectangular.

[0028] 7(b), the dashed line Z5 indicates the horizontal position of the upper surface of the partition plate 15, and a predetermined gap D3 is provided between the lower end of the mixing blade 14a facing the upper surface of the partition plate 15. By providing the predetermined gap D3 between the upper surface of the partition plate 15, the powder and granular material on the partition plate can be allowed to flow down into the flow path of the supply plate 20 while being stirred without being crushed.

[0029] FIG. 8 is a side view illustrating the relative inclination angle (elevation angle) of the agitator blade 14a with respect to the horizontal plane. The relative inclination angle of the agitator blade 14a provided on the inclined surface of the base 14b of the agitator 14 with respect to the horizontal plane can be set to a plurality of angles depending on the particle size, angle of repose, angle of collapse, angle of difference, degree of compression, and other physical characteristics of the powder or granular material to be handled. FIG. 8(a) shows a state in which the relative inclination angle with respect to the horizontal plane is 160 degrees, and FIG. 8(g) shows a state in which the inclination angle is 0 degrees or 180 degrees (parallel to the horizontal plane). Similarly, FIGS. 8(b) to 8(f) show states in which the relative inclination angle with respect to the horizontal plane is 135 degrees, 110 degrees, 90 degrees, 70 degrees, and 45 degrees, respectively.

[0030] FIG. 9 is a diagram for explaining the stirring of powdered granular material by the stirrer 14. In FIG. 9, a partial perspective view is shown with the cylindrical lower reservoir 13 removed. As shown in FIG. 9, the stirring blade 14a of the stirrer 14 that stirs the powdered granular material extends in the radial direction of the lower reservoir 13 and rotates counterclockwise inside the reservoir. A partition plate 15 provided on the receiver 16 is arranged below the stirring blade 14a. In the lower reservoir in which the stirrer 14 is arranged, the partition plate 15 is arranged so as to cover a substantially annular sector-shaped peripheral area including a peripheral area of ​​the outlet 19 provided on the receiver 16 between the lower reservoir 13 and the receiver 16.

[0031] As explained with reference to Fig. 6, the deflector plate 18, which deflects the powder on the outer periphery of the supply plate 20 toward the outside of the periphery, is provided on the front end side of the discharge port 19 with respect to the direction of rotation of the supply plate 20. The powder transferred by the rotation of the supply plate 20 is deflected toward the outside of the periphery by the deflector plate 18 and discharged from the discharge port 19. After passing through the discharge port 19, the powder on the outer periphery of the supply plate 20 rotating below the partition plate 15 is removed.

[0032] As already explained, the agitator 14 and the supply plate 20 supported by the vertical shaft 30 rotate concentrically at the same rotation speed. Therefore, the powder on the partition plate transferred by the agitator blades 14a falls naturally onto the outer peripheral edge 20a of the supply plate 20, which rotates under the partition plate 15 and from which the powder has been removed, and flows down into the flow path formed in the supply plate 20. In the powder feeder 1, the agitator 14 and the supply plate 20, which rotate concentrically at the same rotation speed, can also be said to be a discharge mechanism that discharges the powder from the discharge port 19.

[0033] As a result, with the agitator 14 and supply plate 20 rotating concentrically at the same rotation speed, it becomes possible to fill the powder or granular material contained in the lower reservoir 13 by allowing it to flow naturally down into the flow path formed on the outer periphery. In the powder supplying machine 1 according to this embodiment, the work equivalent to the manual work of filling a specific volume meter of the JIS standard with powder or granular material can be provided by the powder or granular material processing process of the agitator 14 and supply plate 20 rotating concentrically at the same rotation speed.

[0034] (Specific volume measurement system) Next, a specific volume measuring system 100 according to this embodiment will be described. Fig. 10 is a diagram showing an example of the configuration of the specific volume measuring system 100 according to this embodiment. The measurement system 100 is a system capable of continuously measuring the specific volume based on the change in mass of powder or granular material discharged in a predetermined period of time and the volume of powder or granular material discharged according to the rotation speed (rpm) of the concentrically rotating agitator 14 and feeder plate 20. As shown in Fig. 10, the specific volume measurement system 100 includes an input feeder 101 that introduces powder or granular material to be processed into the powder feeder 1, the powder feeder 1, and load cells 103 and 104 that detect the weight of the powder feeder 1 to which a predetermined amount of powder or granular material has been supplied. The specific volume measurement system 100 also includes a pulse sensor 102, a load cell amplifier 105, an inverter motor 106, an F / V converter 108, a frequency divider circuit 109, the load cell amplifier 105, an inverter 107, and a control device 110.

[0035] The weight signals detected by the load cells 103 and 104 are converted into digitized weight data via the load cell amplifier 105 and output to the control unit 112. The load cells 103 and 104 and the load cell amplifier 105 constitute a weight sensor. The pulse sensor 102 transmits a pulse signal according to the rotation of the vertical shaft 30 which supports the supply plate 20 and the agitator 14 and rotates at a predetermined number of revolutions (rpm, also called rotation speed). The pulse signal transmitted from the pulse sensor 102 is converted into a rotation number (rpm) signal via an F / V (frequency / voltage) converter 108 and output to the control unit 112. The pulse signal transmitted from the pulse sensor 102 is divided via a frequency divider circuit 109 and output to the control unit 112 as a synchronization signal which generates one pulse for each rotation of the vertical shaft 30. The pulse sensor 102, the F / V converter 108, and the frequency divider circuit 109 constitute a counting sensor which counts the number of rotations of the supply plate 20 of the powder feeder 1.

[0036] The inverter motor 106 is interlocked with the rotary drive mechanism housed in the housing case 31, and drives the vertical shaft 30 that rotates the supply plate 20, the agitator 14, and the agitator blade 11 at a predetermined rotation speed (rpm). The rotation speed (rpm) of the inverter motor 106 is set via the control device 110. The control unit 112 of the control device 110 outputs a control signal to the inverter 107 according to the rotation speed (rpm) that is set in advance or specified by the operator. The inverter 107 generates a voltage and frequency that drives the inverter motor 106 at the rotation speed (rpm) according to the control signal, and outputs it to the inverter motor 106. The inverter motor 106 rotates the supply plate 20, the agitator 14, and the agitator blade 11 that are supported by the vertical shaft 30 of the powder feeder 1 at the predetermined rotation speed (rpm) set by the control device 110.

[0037] The control device 110 is a computer that manages and controls the operation and processing of the specific volume measurement system 100. The control device 110 includes a graphic panel 111 and a control unit 112. The control unit 112 is a control unit that controls the overall operation of the control device 110, and includes a processor such as a CPU or MPU, and memories such as a flash memory, RAM, and ROM. Various programs, various tables, and various data are stored in the memory, etc., so that they can be read and written. The control unit 112 develops the programs, etc. stored in the memory, etc., so that the processor can execute them, and provides functions that meet a predetermined purpose through the execution of the programs. The graphic panel 111 is a device that displays and outputs data and information processed by the control unit 112 and data and information stored in the memory. The graphic panel 111 also includes an input device such as a touch panel, and receives operation inputs from an operator and operation instructions such as various settings through the input device.

[0038] The control unit 112 of the control device 110 receives operational input from an operator via the graphic panel 111, and sets upper and lower limit weight values ​​for a predetermined amount of powder or granular material to be supplied to the powder feeder 1. The control unit 112 monitors weight data output from the weight sensor, and controls the operation of the receiving feeder 101. For example, when the weight data output from the weight sensor reaches a lower limit weight value, the control unit 112 causes powder or granular material to flow from the receiving feeder 101 into the powder feeder 1. When the weight data output from the weight sensor reaches the upper limit weight value, the control unit 112 controls the operation of the receiving feeder 101. If so, the receiving feeder 101 is stopped, and the inflow of powdered material into the powder feeder 1 is stopped. This allows the powder feeder 1 to store a supply amount of powdered material that does not exceed the upper limit weight value. During operation of the specific volume measurement system 100, the control device 110 repeatedly operates and stops the receiving feeder 101, which causes the powdered material to flow into the powder feeder 1, based on the upper limit weight value and the lower limit weight value set by an operator or the like.

[0039] Furthermore, the control unit 112 of the control device 110 sets the rotation speed (rpm) of the inverter motor 106, which becomes the rotation speed (rpm) of the vertical shaft 30 of the powder feeder 1, according to the physical properties of the powder or granular material that is the target of specific volume measurement. The vertical shaft 30 that is driven in conjunction with the inverter motor 106 can rotate at a rotation speed of, for example, 15 rpm or less.

[0040] Examples of physical properties of powders and granular materials include the angle of repose, the angle of collapse, the difference angle, and the degree of compression. The angle of repose is the maximum angle of the slope at which the powder and granular materials remain stable when piled up without collapsing spontaneously. The angle of collapse is the angle at which the powder and granular materials collapse when a certain impact is applied while maintaining the angle of repose. The angle of difference is the angle that is the difference between the angle of repose and the angle of collapse. The degree of compression is a value that indicates the degree to which the volume of the powder and granular materials is reduced by vibration or pressure. The degree of compression is expressed by the following formula (1). Note that bulk density is the density measured using a dedicated specific volume meter that complies with the JIS standard, and tapped density is the density measured using a powder tester or the like. Compressibility (%) = {1-(bulk density) / (tap density)} Equation (1)

[0041] The control unit 112 starts measuring the specific volume of the powder or granular material after a certain period of time has elapsed since the weight data output from the weight sensor reaches the upper weight limit. Since the relative fluctuation range of the weight signals detected by the load cells 103 and 104 is large during the certain period of time after the upper weight limit is reached, by starting to measure the specific volume after the period of time has elapsed, it is expected that the measurement accuracy will be improved.

[0042] The specific volume is measured at a predetermined periodic interval. The powder feeder 1 discharges a predetermined volume of powder from the discharge port 19 according to the cross-sectional area formed by the upper surface of the outer peripheral edge portion 20a of the feeder board 20, the side surface of the cylindrical body 20b, the peripheral wall surface of the peripheral wall portion 16b of the receiver 16, and the lower surface of the partition plate 15, and the number of rotations (N times) of the feeder board 20. Therefore, the control unit 112 can count the synchronization signal outputted via the frequency divider circuit 109, which generates one pulse for each rotation of the vertical shaft 30, for example, and use the counted number of rotations, such as 3, 7, or 10, as the unit rotation (N times) for measuring the specific volume. Note that the synchronization signal is not limited to one that generates one pulse for each rotation of the vertical shaft 30.

[0043] In addition, since the supply plate 20 of the powder supplying machine 1 rotates at a predetermined rotation speed (rpm) according to the physical properties of the powder or granular material, time intervals such as 1 minute, 5 minutes, or 10 minutes can be used as the unit time for measuring the specific volume. The predetermined volume of the powder or granular material discharged from the powder supplying machine 1 can be obtained by multiplying the rotation speed (rpm) set by the control unit 112 by the unit time for measurement.

[0044] The control unit 112 acquires weight data (weight value) output from the weight sensor for each unit rotation (N times), which is a predetermined periodic interval, for example. Then, the control unit 112 calculates a difference value (differential weight value, ΔWn) from two pieces of weight data acquired before and after the predetermined periodic interval. Since the volume of the powder or granular material discharged from the powder feeder 1 per unit rotation is a fixed amount, if the fixed amount is taken as fixed volume data (ΔV), the apparent specific gravity (BD value, g / ml) of the powder or granular material discharged at the predetermined periodic interval is expressed by the following formula (2). BDn (apparent specific gravity, g / ml) = ΔWn / ΔV Equation (2)

[0045] The control unit 112 calculates the apparent specific gravity (BDn) calculated for each unit rotation (N times). The average is calculated, and the specific volume (ml / g) of the powder or granular material is calculated from the calculated specific gravity average value (BDav). The control unit 112 stores the calculated specific volume of the powder or granular material in a memory or the like, and displays the data value of the calculated specific volume on the graphic panel 111 or the like. In the control device 110, the specific volume value of the powder or granular material calculated by the moving average, the transition of the specific volume value over time, the fluctuation range of the specific volume value, etc. can be grasped via the graphic panel 111 or the like. In this embodiment, it is possible to continuously measure the specific volume of the powder or granular material in the processing process. When measuring the specific volume, there is no need to temporarily stop the operation of the powder feeder 1, and there is no risk of variation in the measurement value due to manual work.

[0046] In calculating the specific volume, the control unit 112 corrects the specific volume calculated from the specific gravity average value (BDav) based on the amount of loss occurring during the process of the powder feeder 1. Such an amount of loss is, for example, an amount of loss that may occur due to a portion of the powder or granule that cannot reach the discharge port 19 by flowing out from the gap between the upper surface of the outer peripheral edge portion and the lower end of the deflection plate 18 when passing through the above-mentioned cross-sectional area. Therefore, the control unit 112 stores the amount of loss measured in advance for each powder or granule to be processed in a memory or the like. Then, the control unit 112 reads out the amount of loss stored in the memory or the like according to the powder or granule to be processed instructed via the graphic panel 111 or the like, and corrects the specific volume of the powder or granule calculated from the specific gravity average value (BDav). In this embodiment, the measurement accuracy of the specific volume can be improved by correcting the specific volume based on the amount of loss occurring during the process.

[0047] In addition, the control unit 112 corrects the specific volume calculated from the average specific gravity (BDav) based on the compression degree (compressibility) of the powder or granular material. In the area other than the area covered by the partition plate 15, the powder or granular material transferred by the supply board 20 of the powder supplying machine 1 is subjected to a powder pressure from above according to the amount of powder or granular material stored in the lower reservoir 13. In terms of physical properties of powder or granular material, powder or granular material with a relatively high compression degree is more affected by the powder pressure from above. Therefore, the control unit 112 stores a correction value according to the compression degree of the powder or granular material to be processed in a memory or the like. Then, the control unit 112 reads out the correction value stored in the memory or the like according to the powder or granular material to be processed instructed via the graphic panel 111 or the like, and corrects the specific volume of the powder or granular material calculated from the average specific gravity (BDav). In this embodiment, the specific volume calculated according to the compression degree of the powder or granular material can be corrected, so that the specific volume can be measured with high accuracy.

[0048] [Measurement results] In order to confirm the accuracy of the specific volume measured by the powder feeder 1 according to this embodiment, a comparison measurement was performed between the specific volume measured by the powder feeder 1 and the specific volume measured by a specific volume meter conforming to the JIS standard. The comparison measurement was performed to measure the specific gravity (kg / L) of seven types of powder A to powder G. Powder A is, for example, Hon Dashi (registered trademark), powder B is MSG RC (L-sodium glutamate RC), and powder C is MSG FC (L-sodium glutamate FC), all of which are manufactured by Ajinomoto Co., Inc. Powder D is table salt (Nakurufo 2) manufactured by Naikai Salt Co., Ltd. Powder E is lactose manufactured by Granvia Co., Ltd. Powder F is chicken extract powder manufactured by Nikken Food Co., Ltd. Powder G is whole chicken bone soup manufactured by Ajinomoto Co., Inc. The comparison results for each powder or granule are explained using Tables Tb1 to Tb6.

[0049] Tables Tb1 to Tb6 show, as operating condition items, the relative angle (blade angle) of the agitator blade 14a provided on the agitator 14 to the horizontal plane, the rotation speed (rpm) of the agitator 14 and the feeder plate 20, and the amount of powder and granular material loss (cc). The agitator blade 14a has three blades, which are provided at equal intervals of approximately 120 degrees around the periphery of the base 14b. In addition, the specific gravity measurement items include loose density (g / cc), hardened density (g / cc), density when powder pressure is applied (kg / L), JIS specific gravity (kg / L), specific gravity measured by the feeder (kg / L), and feeder loss correction value. The density (kg / L) is shown. The loose density indicates the bulk density and is the JIS specific gravity measured using a specific volume meter, and the hard density indicates the tap density measured using a powder tester or the like. The density under powder pressure is the density measured when the powder is piled up from the top of a loosely packed container to the height of the agitator area (e.g., 75 mm) and then the piled up powder is removed from the top. The density under powder pressure defines the density of the powder compressed by a specified amount of powder pressure. As mentioned above, the JIS specific gravity is synonymous with the loose density, but it describes the measurement value of the loose density measured on the powder discharged from the powder feeder 1 during measurement. The feeder measured specific gravity indicates the specific gravity measured by the powder feeder 1, and the feeder loss correction value indicates the feeder measured specific gravity corrected by the amount of loss.

[0050] Furthermore, in Tables Tb1 to Tb6, the following evaluation items are shown: no correction, correction for loss amount, and correction for loss amount + correction for the effect of powder pressure. For each evaluation item, the error rate (feeder / manual measurement) represents the error rate (%) of the specific gravity measured by the feeder 1 relative to the JIS specific gravity of the powder or granular material measured manually, and is expressed by the following formula (3). The evaluation of the error rate is represented by "○" indicating conformity for an error of less than 1% and an error of less than 3%, respectively. Error rate (%) = {1-(feeder measured specific gravity) / (JIS specific gravity)} Formula (3)

[0051] The loss amount correction represents the error rate (%) of the feeder loss correction value for the powder / granular material, which is manually performed, relative to the JIS specific gravity, and is expressed by the following formula (4). The error rate is evaluated with a "○" indicating conformity for errors of less than 1% and errors of less than 3%, respectively. Error rate (%) = {1-(supply machine loss correction value) / (JIS specific gravity)} ·· Equation (4)

[0052] The loss amount correction + powder pressure effect correction represents the error rate (%) of the feeder loss correction value for the density when powder pressure is applied, and is expressed by the following formula (5). The evaluation of the error rate is indicated by "○" indicating conformity for an error of less than 1% and an error of less than 3%, respectively. Error rate (%) = {1-(supply machine loss correction value) / (density when powder pressure is applied)}··Equation (5)

[0053] Example 1 FIG. 11 is a diagram showing the measurement results of powdered or granular material A. In the comparative measurement of powdered or granular material A, the blade angle of the agitator 14 was fixed at 90 degrees, and the specific gravity (kg / L) was measured at the rotation speed of the agitator 14 and the supply plate 20 at 3 rpm, 5 rpm, 7 rpm, and 9 rpm. Similarly, the blade angle of the agitator 14 was fixed at 45 degrees, and the specific gravity (kg / L) was measured at the rotation speed of 5 rpm. No loss of powdered or granular material was confirmed under any of the above operating conditions. As shown in Table Tb1 of FIG. 11, the comparative measurement results for powdered or granular material A showed good results with an error rate of less than 3% without correction. Under the operating conditions of a blade angle of 90 degrees and rotation speeds of 7 rpm and 9 rpm, and a blade angle of 45 degrees and rotation speed of 5 rpm, the error rate without correction was less than 1%. The compression degree (compressibility) of powdered or granular material A is 3.0 percent. For powder A, multiple results were obtained with an error rate of less than 1% without correction, so measurements were not made with loss amount correction or with loss amount correction + powder pressure effect correction.

[0054] Example 2 Fig. 12 is a diagram illustrating the measurement results for powdered materials B and C. As shown in table Tb2 in Fig. 12, comparative measurements were made for powdered materials B and C at three blade angles of 45 degrees, 90 degrees, and 135 degrees and two rotation speeds (3 rpm and 7 rpm). Under the above operating conditions, a predetermined amount of loss was confirmed for both powdered materials B and C.

[0055] For powder B, the error rate (%) of the specific gravity measured by the feeder against the JIS specific gravity exceeded 3% without any correction under all operating conditions. When correction was made to the measured specific gravity measured by the feeder based on the confirmed loss amount (cc) (feeder loss correction value), the error rate (%) of the specific gravity measured by the feeder against the JIS specific gravity was less than 3% under all operating conditions. This confirmed that the error rate (%) against the JIS specific gravity could be reduced by correcting the specific gravity measured by the feeder 1 for the amount of loss that occurs during the processing by the powder feeder 1. It can be seen that correction based on the amount of loss that occurs during the processing by the powder feeder 1 is effective in improving the measurement accuracy of the specific volume.

[0056] Furthermore, when the powder pressure of the powdered material contained in the lower reservoir 13 is taken into consideration in addition to the correction of the loss amount (correction of the loss amount + correction of the effect of the powder pressure), it was confirmed that the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity is reduced. For example, except for the operating condition in which the agitator 14 and the supply plate 20 are rotated at a rotation speed of 7 rpm with a blade angle (45 degrees, 135 degrees), the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity is less than 1% under other operating conditions. It was confirmed that further improvement in measurement accuracy was achieved by making corrections taking into consideration the powder pressure of the powdered material contained in the area above the supply plate 20 where the agitator 14 rotates.

[0057] For powder C, the error rate (%) of the feeder measured specific gravity against the JIS specific gravity was less than 3% without correction for all operating conditions. With correction based on the amount of loss (feeder loss correction value), the error rate (%) was less than 3% for all operating conditions except for an operating condition of 3 rpm with a blade angle of 45 degrees. In addition, with correction taking powder pressure into account (correction for the amount of loss + correction for the effect of powder pressure), the error rate (%) was less than 3% for all operating conditions, and it was confirmed that the error rate (%) was less than 3% at a rotation speed of 3 rpm.

[0058] For granular material C, it was confirmed that when correction was made taking into account the amount of loss of the granular material, the error rate (%) tended to become negative. When comparing the powder properties of granular material B and granular material C, there was not much difference in the angle of repose, collapse angle, and difference angle, but a difference was observed in the degree of compression (%). For example, the degree of compression (%) of granular material B was 1.70, while that of granular material C was 4.24, which is relatively high. The error rate of loss amount correction taking into account the amount of loss of granular material B and C was a positive value for granular material B and a negative value for granular material C, so it is presumed that the above tendency is due to the degree of compression of the granular material.

[0059] Example 3 Fig. 13 is a diagram for explaining the measurement results of powder D. As shown in table Tb3 in Fig. 13, for powder D, comparative measurements were made at two rotation speeds (3 rpm and 7 rpm) for blade angles of 0 degrees, 45 degrees, 70 degrees, 90 degrees, 135 degrees, 160 degrees, and 180 degrees. At a blade angle of 90 degrees, a rotation speed of 12 rpm was added to the operating conditions. The compression degree (%) of powder D was 4.06, and the specified amount of loss was confirmed.

[0060] For powder D, the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity was generally less than 3% without correction. Even under operating conditions where the error rate (%) exceeded 3%, such as the rotation speeds of 3 rpm and 12 rpm with a blade angle of 90 degrees, and 7 rpm with a blade angle of 135 degrees, the error rate (%) for each was in the 3% range. For powder D, it was confirmed that the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity without correction was generally less than 3% within the blade angle range of 45 degrees to 180 degrees.

[0061] In the state of correction based on the amount of loss (feeder loss correction value), it was confirmed that the error rate (%) also tended to be a negative value for powder D, and the error rate (%) was less than 3% under the operating conditions except for the operating condition of a blade angle of 45 degrees and a rotation speed of 7 rpm. In particular, when the blade angle was in the range of 70 degrees to 180 degrees, the error rate (%) was in the range of -1.8% to 0.4%. It was confirmed that the error rate (%) was within the -3% range when the blade angle was 45 degrees and the rotation speed was 7 rpm.

[0062] Additionally, for powder D, it was confirmed that the error rate (%) tended to be less than 1% at a rotation speed of 3 rpm. In the blade angle range of 90 degrees to 180 degrees, it was confirmed that the error rate (%) was less than 1% under all operating conditions except for a blade angle of 160 degrees, a rotation speed of 180 degrees and 7 rpm. The error rate (%) at a blade angle of 160 degrees, a rotation speed of 180 degrees and 7 rpm was -1.1%. Therefore, it can be said that the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity, taking into account the amount of loss, is generally less than 1%.

[0063] It was confirmed that when compensation was made taking powder pressure into account (compensation for loss amount + compensation for the effect of powder pressure), the error rate (%) for operating conditions with blade angles of 45 degrees, 90 degrees, and 135 degrees tended to be less than 3%. At a blade angle of 90 degrees, it was confirmed that the difference rate (%) was less than 1%. Furthermore, it was confirmed that when compensation was made taking powder pressure into account (compensation for loss amount + compensation for the effect of powder pressure), the error rate (%) tended to become a negative value.

[0064] Example 4 Fig. 14 is a diagram explaining the measurement results of powder / granular material E. As shown in table Tb4 in Fig. 14, for powder / granular material E, comparative measurements were performed using two rotation speeds (3 rpm, 7 rpm) as operating conditions for each of the blade angles of 45 degrees, 90 degrees, and 135 degrees. Powder / granular material E has the highest powder physical properties of the powder materials involved in the comparative measurements, namely, the degree of compression (24.34%), the angle of repose (47.1 degrees), and the difference angle (18 degrees).

[0065] For powder E, without correction, the error rate (%) of the feeder measured specific gravity against the JIS specific gravity exceeded 3% except for the operating conditions of a blade angle of 135 degrees and a rotation speed of 7 rpm. It was confirmed that the error rate (%) exceeded 3% regardless of the operating conditions when correction was made based on the amount of loss (feeder loss correction value). It was confirmed that the error rate (%) exceeded 3% regardless of the operating conditions when correction was made taking into account the powder pressure (correction for the amount of loss + correction for the effect of powder pressure), and that the error rate (%) was less than 3% only when the operating conditions were a blade angle of 90 degrees. It can be seen that the error rate (%) was less than 3% when the operating conditions were a blade angle of 90 degrees and rotation speeds of 3 rpm and 7 rpm.

[0066] It was confirmed that the error rate (%) of the specific gravity measured by the feeder relative to the JIS specific gravity was a negative value for powder E, even without correction. Powder E has high powder properties, such as a high degree of compression (24.34%), angle of repose (47.1 degrees), and angle of difference (18 degrees), and it is presumed that powders with such powder properties tend to easily contain air.

[0067] Example 5 Fig. 15 is a diagram for explaining the measurement results of granular material F. As shown in table Tb5 in Fig. 15, for granular material F, comparative measurements were performed using two rotation speeds (3 rpm and 7 rpm) as operating conditions for each of the blade angles of 45 degrees, 90 degrees, and 135 degrees. Granular material F also has relatively high powder physical properties, with a degree of compression of 17.16%.

[0068] For powder F, without correction, the error rate (%) of the feeder measured specific gravity against the JIS specific gravity was less than 3% for all operating conditions. It was confirmed that the error rate (%) was less than 1% under operating conditions with a blade angle of 45 degrees, 90 degrees, and a rotation speed of 3 rpm. On the other hand, with correction based on the amount of loss (feeder loss correction value), it was confirmed that the error rate (%) exceeded 3% regardless of the operating conditions. With correction taking into account powder pressure (correction for the amount of loss + correction for the effect of powder pressure), it was confirmed that the error rate (%) was less than 3% under all operating conditions, and that with an operating condition with a blade angle of 45 degrees, 90 degrees, and a rotation speed of 3 rpm, the error rate (%) was less than 1%.

[0069] Although powder F has relatively high powder properties with a degree of compression of 17.16%, the difference between the angle of repose and the angle of collapse is small, and the JIS specific gravity value measured manually is relatively small. Therefore, it is estimated that the error rate (%) will be a negative value when corrected based on the amount of loss (feeder loss correction value), but the error rate (%) will be a positive value when there is no correction and when corrected taking into account the powder pressure (correction for the amount of loss + correction for the effect of powder pressure).

[0070] Example 6 Fig. 16 is a diagram explaining the measurement results of powder / granular material G. As shown in table Tb6 in Fig. 16, for powder / granular material G, comparative measurements were performed under operating conditions of a rotation speed of 3 rpm for a blade angle of 45 degrees, 7 rpm for a blade angle of 90 degrees, and two rotation speeds (3 rpm, 7 rpm) for a blade angle of 135 degrees. Powder / granular material G has relatively high powder physical properties, such as an angle of repose (46.8 degrees) and a difference angle (17 degrees), among the powder / granular materials involved in the comparative measurements.

[0071] For powder G, without any correction, the error rate (%) of the specific gravity measured by the feeder against the JIS specific gravity exceeded 3% for all operating conditions. With correction based on the amount of loss (feeder loss correction value), it was confirmed that the error rate (%) exceeded 3% regardless of the operating conditions. With correction taking into account powder pressure (correction for the amount of loss + correction for the effect of powder pressure), it was confirmed that the error rate (%) was less than 3%.

[0072] Although the compressibility (%) of powder G is smaller (9.84%) than that of powder E, the angle of repose (46.8 degrees) and the difference angle (17 degrees) are high powder properties similar to those of powder E. It is presumed that powder G, which has such powder properties, also has a tendency to easily contain air, similar to powder E.

[0073] From the measurement results shown in Tables Tb1 to Tb6, it was confirmed that the error rate (%) relative to the JIS specific gravity could be reduced and the measurement accuracy could be improved by correcting the amount of loss that occurs during the processing by the powder feeder 1. Furthermore, in addition to correcting the amount of loss, it was confirmed that the error rate (%) could be reduced and the measurement accuracy could be further improved by making a correction taking into account the powder pressure of the powder or granular material contained in the area above the supply board 20 where the agitator 14 rotates. In other words, it was confirmed that correction based on powder pressure is effective for powder or granular material that is greatly affected by powder pressure (high degree of compression).

[0074] Furthermore, the measurement results confirmed that it is possible to measure specific gravity by appropriately selecting the blade angle of the agitator blade 14a relative to the horizontal plane and the rotation speed (rpm) of the agitator 14 and the supply plate 20 according to the physical properties of the powder or granular material (angle of repose, collapse angle, difference angle, compressibility, etc.). For example, as shown for powder or granular material A in table Tb1, it was confirmed that when the degree of compression (compressibility) as a physical property of the powder or granular material is 3.0 percent or less, the error rate (%) without correction for the measured value according to the JIS method can be controlled to within a range of less than 3% under the following conditions (operating conditions). Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is 45 degrees or more and less than 135 degrees, and the rotation speed is in the range of 3 rpm to 9 rpm.

[0075] Furthermore, as shown for powder B in Table Tb2, it has been confirmed that when the degree of compression (compressibility) as a physical property of the powder is 2.0 percent or less, by making corrections based on at least one of the correction amounts for the loss amount and powder pressure, the error rate (%) relative to the measurement value according to the JIS method can be controlled within a certain range under the following conditions (operating conditions). Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm.

[0076] In addition, as shown in Table Tb3 for powder D, the degree of compression is one of the physical properties of powder. When the compression ratio is less than 4.1 percent (more than 2 percent when considering Table Tb2), it has been confirmed that by making corrections based on at least one of the correction amounts for the loss amount and powder pressure, it is possible to control the error rate (%) relative to the measurement value according to the JIS method within a certain range of less than 3% under the following conditions (operating conditions). Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is in the range of 45 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm.

[0077] It was confirmed that for powder D, by limiting the correction to the amount of loss, the error rate (%) relative to the measured value according to the JIS method can be controlled within a certain range under the following conditions (operating conditions): Operating conditions in which the inclination angle of the agitating blade 14a with respect to the horizontal plane is in the range of from 45 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm. However, preferably, the operating conditions are in the range of 70 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm.

[0078] Furthermore, for powder D, under operating conditions where the inclination angle of the agitator blade 14a with respect to the horizontal plane is in the range of 45 degrees to 180 degrees and the rotation speed is in the range of 3 rpm to 12 rpm, it was confirmed that the error rate (%) without correction to the measurement value according to the JIS method can be controlled to a certain range of at most 3%.

[0079] Furthermore, as shown in Table Tb2 for powder C, it was confirmed that when the degree of compression (compressibility) as a physical property of the powder is less than 4.3 percent, the error rate (%) relative to the measurement value according to the JIS method can be controlled within a certain range of less than 3% without making any corrections under the following conditions (operating conditions). Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm.

[0080] Furthermore, as shown in Tables Tb5 to Tb6, when the compression degree (compression rate) is between 9.8 percent and 17.2 percent, it has been confirmed that the error rate (%) relative to the measurement value according to the JIS method can be controlled within a certain range of less than 3% under the following conditions (operating conditions) by either correcting the effect of the loss amount or correcting both the effect of the loss amount and the effect of powder pressure. Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is in the range of 45 degrees to 180 degrees (0 degrees), and the rotation speed is in the range of 3 rpm to 12 rpm.

[0081] Furthermore, as shown in Table Tb4, when the compression degree (compression rate) exceeds 24.3 percent, it has been confirmed that the effect of the loss amount and the effect of the powder pressure can be corrected and the error rate (%) relative to the measurement value according to the JIS method can be controlled within a certain range under the following conditions (operating conditions). Operating conditions in which the inclination angle of the agitator blade 14a with respect to the horizontal plane is greater than 45 degrees and less than 135 degrees, and the rotation speed is 3 rpm to 7 rpm.

[0082] Furthermore, through the measurement results, it was found that when the rotation speed of the agitator 14 and the supply plate 20 is 3 rpm, the value tends to be close to the JIS specific gravity value. Also, it was found that for powders with good fluidity such as crystals and granules, the error rate (%) with respect to the JIS specific gravity tends to be small when the blade angle of the agitator blade 14a is 90 degrees. [Explanation of symbols]

[0083] REFERENCE SIGNS LIST 1 powder feeder, 10 upper reservoir, 11 a mixing blade, 11 a end plate, 12 pressure adjustment plate, 12 a delivery port, 12 b insertion hole, 13 lower reservoir, 14 mixing body, 14 a mixing blade, 14 b base, 14 c insertion structure, 15 partition plate , 16··receptor, 16a··bottom surface, 16b··circumferential wall, 16c··through hole, 17··fixed blade, 18··deflection plate, 19··discharge port, 20··supply board, 20a··outer rim, 20b··cylindrical body, 20c··through structure, 20d··knurling, 21··wheel scraping blade, 30··vertical shaft, 31··storage case, 32··lifting tray, 100··specific volume measurement system, 101··receiving feeder, 102··pulse sensor, 103··load cell, 104··load cell, 105··load cell amplifier, 106··inverter motor, 107··inverter, 108··F / V converter, 109··frequency divider circuit, 110··control device, 111··graphic panel, 112··control unit

Claims

1. An upper storage body that stores a predetermined amount of supplied powder and granules and discharges the stored powder and granules from a discharge port, and a lower storage body that contains the powder and granules discharged from the upper storage body, A receptor is connected to the lower part of the lower storage body as the bottom of the lower storage body and has a bottom surface portion and a peripheral wall portion having an outlet for discharging the powder and granular material formed in a part of the peripheral wall connected to the bottom surface portion, A stirring body rotates within the lower storage chamber to agitate the powder and granular material contained within the lower storage chamber, The system comprises a supply plate provided between the lower reservoir and the receptor, parallel to the bottom of the receptor, which rotates concentrically with the agitator within the receptor and has a flow path formed therein for transporting the powdered material agitated by the agitator and introducing it into the discharge port of the receptor, The supply plate includes an outer peripheral edge formed in a flange shape of a predetermined width from the outer circumference and a cylindrical body that forms a step on the inside of the outer peripheral edge with respect to the upper surface of the outer peripheral edge. The receptor is provided with a partition plate above the supply plate, parallel to the supply plate, which aligns the powder and granules on the supply plate to a predetermined height, and a deflection plate on the outer peripheral edge which deflects the powder and granules being transported in the rotational direction of the supply plate toward the outer peripheral edge of the supply plate. The supply plate is a powder supply machine that continuously discharges a predetermined volume of powder or granular material from the discharge port, corresponding to the number of rotations of the concentric rotation and the cross-sectional area formed by the upper surface of the outer peripheral edge, the peripheral wall surface of the peripheral wall, the lower surface of the partition plate, and the side surface of the cylindrical body. A weight sensor measures the weight of the powder dispenser to which a predetermined amount of powder has been supplied, and outputs a signal corresponding to the measured weight. A counting sensor for counting the number of rotations of the supply plate of the powder supply machine, At a minimum, the powder feeder is operated under the conditions that the angle of inclination of the stirring blades of the agitator with respect to the horizontal plane is set according to the physical properties of the powder, and that the agitator and the feed plate rotate at the same rotational speed, A control unit that acquires the weight value of the powder feeder measured via the weight sensor at predetermined periodic intervals, calculates a differential weight value which is the difference between the two weight values ​​acquired before and after the predetermined periodic interval, and calculates the specific volume of the powder based on the differential weight value, the unit volume value of the powder discharged from the discharge port of the powder feeder for each unit rotation of the feed plate, and the number of rotations in the predetermined periodic interval, A specific volume measurement system equipped with the following features.

2. The control unit operates the powder feeder under the conditions that the compressibility of the powder is 2 percent or less, the inclination angle of the stirring blades with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm, and calculates the specific volume by making corrections based on the amount of loss of the powder supplied to the powder feeder that cannot reach the discharge port and at least one correction amount of powder pressure. The specific volume measurement system according to claim 1.

3. The specific volume measurement system according to claim 1, wherein the control unit operates the powder feeder under the conditions that the compressibility of the powder is 3 percent or less, the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 45 degrees or more and less than 135 degrees, and the rotation speed is in the range of 3 rpm to 9 rpm.

4. The control unit operates the powder feeder under the conditions that the compressibility of the powder is less than 4.1 percent, the inclination angle of the stirring blades with respect to the horizontal plane is in the range of 45 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm, and calculates the specific volume by making corrections based on the amount of loss of the powder supplied to the powder feeder that cannot reach the discharge port and at least one correction amount of powder pressure. The specific volume measurement system according to claim 1.

5. The specific volume measurement system according to claim 4, wherein the control unit operates the powder feeder under the conditions that the inclination angle of the stirring blade with respect to the horizontal plane is in the range of more than 45 degrees to 180 degrees and the rotation speed is in the range of 3 rpm to 12 rpm, and calculates the specific volume by making a correction based on the amount of loss of the powder that cannot reach the discharge port supplied to the powder feeder.

6. The specific volume measuring system according to claim 4, wherein the control unit operates the powder feeder under the conditions that the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 45 degrees to 180 degrees and the rotation speed is in the range of 3 rpm to 12 rpm.

7. The specific volume measuring system according to claim 1, wherein the control unit operates the powder feeder under the conditions that the compressibility of the powder is less than 4.3 percent, the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 45 degrees to 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm.

8. The specific volume measurement system according to claim 1, wherein the control unit operates the powder feeder under the conditions that the compressibility of the powder is between 9.8 percent and 17.2 percent, the inclination angle of the stirring blade with respect to the horizontal plane is in the range of 45 degrees to 180 degrees, and the rotation speed is in the range of 3 rpm to 12 rpm, and calculates the specific volume by correcting the powder pressure of the powder supplied to the powder feeder.

9. The specific volume measurement system according to claim 1, wherein the control unit operates the powder feeder under the conditions that, when the compressibility of the powder exceeds 24.3 percent, the inclination angle of the stirring blade with respect to the horizontal plane is greater than 45 degrees and less than 135 degrees, and the rotation speed is in the range of 3 rpm to 7 rpm, and calculates the specific volume by correcting the powder pressure of the powder supplied to the powder feeder.

10. The control unit sets an upper and lower weight limit for the amount of powder supplied to the powder feeder that is stored in the upper storage container, detects when the weight value of the powder feeder measured by the weight sensor falls below the lower weight limit, and also detects when the amount of powder supplied does not exceed the upper weight limit. The specific volume measuring system according to claim 1, wherein the above is supplied to the upper storage body.

11. The specific volume measurement system according to claim 1, wherein the control unit acquires the weight value of the powder feeder measured via the weight sensor at predetermined intervals of a predetermined number of rotations of the supply plate, set in advance, after a certain period of time has elapsed since a predetermined amount of powder has been supplied to the upper storage body.

12. The specific volume measurement system according to claim 1, wherein the control unit corrects the calculated specific volume based on the amount of loss of the granular material that cannot reach the discharge port because a portion of the granular material passing through the cross-sectional region flows out from the gap between the upper surface of the outer peripheral edge and the lower end of the deflection plate.

13. The specific volume measurement system according to claim 1, wherein the control unit corrects the specific volume calculated based on the compressibility of the powder for powders with a compressibility of 4 percent or more.

14. A storage body having a cylindrical internal space for temporarily storing incoming powder and granular material, A powder supply machine having a discharge mechanism that rotates around the central axis of the cylindrical inner space, causing the powder temporarily stored in the storage container to rotate around the central axis, thereby discharging the powder temporarily stored in the storage container from the discharge port, and A weight sensor for measuring the weight of the powder supply machine in which the powder is temporarily stored, A counting sensor for counting the number of rotations of the supply plate of the aforementioned powder supply machine, A control unit calculates the specific volume of the powder based on the difference in weight value, which is the difference between the weight values ​​obtained at predetermined periodic intervals, and the number of rotations at the predetermined periodic interval. A specific volume measurement system equipped with the following features.

15. A method for calculating specific volume of a powder supply machine having a discharge mechanism that rotates around the central axis of the cylindrical inner space of a storage body for temporarily storing powder and granular material, and rotates the powder and granular material temporarily stored in an upper storage body connected above the storage body around the central axis to discharge the powder and granular material from a discharge port, wherein the powder supply machine is operated under the conditions that the inclination angle of the stirring blades of the stirring body with respect to the horizontal plane is set according to the physical characteristics of the powder and granular material, and that the stirring body and the supply plate of the discharge mechanism rotate at the same rotational speed, and the weight value of the powder supply machine is acquired at predetermined periodic intervals, and the specific volume of the powder and granular material is calculated based on the difference in weight value, which is the difference between the weight values ​​acquired at the predetermined periodic intervals, and the number of rotations at the predetermined periodic intervals.

16. The method for calculating specific volume according to claim 15, wherein the specific volume calculated is corrected based on the amount of loss of the granular material that remains in a receptor connected below the storage body and cannot reach the discharge port.

17. The method for calculating specific volume according to claim 15, wherein the specific volume calculated based on the compressibility of the powder or granules is corrected for powder or granules with a compressibility of 4 percent or more.

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