JP2010107472A - Device and method for feeding fixed quantity of powder and granular material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for feeding a fixed quantity of a powder and granular material for being quickly and accurately weighed from a first batch of weighing start. <P>SOLUTION: The powder and granular material fed from a screw feeder 13 is stored in a weighing hopper 21 having a load cell 22. A controller unit 36 connected to the load cell 22 and the screw feeder 13 sequentially executes a preliminary weighing mode and a main weighing mode. In the preliminary weighing mode, the device obtains increase quantities of weighed values W from feed stop as a first fall value wa and a second fall value wb in a time when the device stops from large feed operation of a large feed speed of the powder and granular material with the screw feeder 13 and another time when the device stops from a small feed operation of a small feed speed, respectively. In the main weighing mode, the weighing value W executes the large feed operation down to a first stop value wd relating to the first fall value wa, and next, the weighing value W executes the small feed operation down to a second stop value we relating to the second fall value wb. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a powder and substance quantitative supply apparatus and a powder and substance quantitative measurement method.

Conventionally, when molding resin pellets and the like with a molding machine, for example, each material such as resin pellets, pulverized materials, master batches, additives, etc., which has been pneumatically transported, is measured at a predetermined ratio by a metering and mixing device. After blending and mixing in step (1), a process is often performed in which the mixture is supplied to the molding machine in a constant amount.
The metering and mixing device used for such processing usually has a plurality of hoppers that accept each material that has been pneumatically transported for each material, and a meter that measures each material that is input from each hopper at a predetermined blending ratio. A unit and a mixing unit for mixing each weighed material, each material received in each hopper is cut out by a cutting means such as a screw feeder provided in each hopper, dropped on the weighing unit, When a predetermined set amount is reached in the weighing unit, the cutting is stopped and each material is weighed. Then, each material weighed in sequence is supplied to the mixing unit and mixed by the stirring blade provided in the mixing unit. Then, a constant amount is supplied.

However, in such a weighing and mixing device, when each material is weighed by the weighing unit, even if the cutting is stopped when the predetermined set amount is reached, the material in the middle of dropping is changed to the material that has reached the set amount. Furthermore, since it is weighted, the part becomes a measurement error.
Here, in order to reduce the measurement error, a method is known in which the supply amount per unit time of the material supplied to the measurement unit is measured in a stepwise manner every time the measurement value reaches a predetermined value. (For example, refer to Patent Documents 1 and 2).

In Patent Document 1, the final adjustment weighing process is performed after the step-down weighing process in which the supply amount per unit time of the material is decreased stepwise.
In Patent Document 2, a predetermined value for a measurement value is corrected after one batch measurement is completed.
JP 2007-47000 A JP 2008-128865 A

In Patent Document 1, the material supply is temporarily stopped in each of the step-down weighing processes. At this time, the material is not immediately dropped, but the material in the middle of dropping enters the weighing unit. In patent document 1, the mass of the material in the middle of the fall at the time of a temporary stop in each step-down measurement process is not fully considered, and it is difficult to increase the measurement accuracy.
In Patent Document 2, it is difficult to increase the measurement accuracy of the first batch at the start of measurement.

  The present invention has been made in view of such circumstances. The object of the present invention is to provide a powder and substance quantitative supply device and a powder that can be measured quickly and accurately from the first batch of measurement start. The object is to provide a method for quantitative measurement of granules.

  In order to achieve the above object, the invention according to claim 1 is an apparatus for quantitatively supplying powder, which includes a supply port for supplying the powder, and supplies the powder from the supply port. And a measuring unit including a measuring unit for measuring the mass of the granular material in the hopper, and a measuring unit connected to the measuring unit. Control means for controlling the supply device, wherein the control means is capable of sequentially executing a preliminary measurement mode and a main measurement mode, and the control means is capable of executing per unit time by the supply device in the preliminary measurement mode. By stopping the supply device from a large supply operation state in which the supply amount of the granular material is relatively large, the increase in the measurement value of the measuring means from the stop until the fall of the granular material ends. First drop By stopping the supply device from a small supply operation state that is obtained as a value and the supply amount of the granular material per unit time by the supply device is relatively small, the powder material from the stop The amount of increase in the measured value until the drop of the liquid is finished is obtained as a second drop value, and in the main measurement mode, the control means determines that the measured value is based on a predetermined target measured value and the first drop value. The large supply operation is executed until a first stop value, which is a difference from the first reference value, and then the measured value is a predetermined second reference based on the target measured value and the second drop value. The small supply operation is performed until a second stop value that is a difference from the value is reached.

  According to such a configuration, the preliminary weighing mode and the main weighing mode are executed in one batch. Therefore, in this measurement mode, the large supply operation is performed up to the first stop value that is the difference between the predetermined first reference value based on the first drop value obtained in the preliminary measurement mode and the predetermined target measurement value, that is, the large supply operation. It can be executed to the limit that can be supplied by the supply operation. As a result, the measured value can be quickly brought close to the target measured value.

  In this measurement mode, the small supply operation is performed from the state in which the measurement value is brought close to the target measurement value by the large supply operation. Therefore, the time for performing the small supply operation is short. Further, the small supply operation is executed up to a second stop value which is a difference between a predetermined second reference value based on the second drop value obtained in the preliminary weighing mode and the target measured value. Therefore, the measured value can be made to substantially match the target measured value by the small supply operation. In addition, more accurate weighing can be performed in the small supply operation than in the large supply operation. Thereby, in the small supply operation, the measurement time can be shortened and extremely accurate measurement can be realized.

From the above, in this weighing mode, based on the pre-weighing mode, a highly accurate operation is ensured from a large supply operation that can achieve extremely quick weighing while ensuring high accuracy, and a state in which the weighing time is shortened. Since the small supply operation capable of realizing the metering is used in combination, extremely fast and accurate metering can be realized.
In addition, in the case of the large supply operation, the first drop value as the drop value in the large supply operation is considered, and in the case of the small supply operation, the second drop value as the drop value in the small supply operation is considered. Thus, since the head value is set corresponding to each operation state, the accuracy of the measurement of the granular material is extremely high. Further, the preliminary weighing mode and the main weighing mode are executed in one batch. Therefore, the weighing can be performed without using the weighing result of the previous batch, and quick and accurate weighing can be realized from the first batch.

According to a second aspect of the present invention, in the first aspect of the present invention, the control means executes both the preliminary weighing mode and the main weighing mode when weighing the first batch in the weighing unit. In the second and subsequent batches of weighing in the weighing unit, the preliminary weighing mode is not executed and the main weighing mode is executed.
According to such a configuration, when the first batch is weighed, preliminary weighing is performed, so that the main weighing is performed from a state in which a predetermined amount of powder is already stored in the hopper. Can do. In addition, when weighing after 2 batches, the pre-weighing mode can be omitted by using the first drop value and the second drop value obtained in the pre-weighing mode executed in the first batch. Therefore, it is possible to quickly measure the granular material.

The invention according to claim 3 is the invention according to claim 1 or 2, wherein the control means sets a value obtained by multiplying the first drop value by a predetermined coefficient as the first reference value. It is said.
According to such a configuration, the first reference value can be set to an arbitrary value based on the first drop value. Therefore, supply error due to large supply operation can be considered.

  According to a fourth aspect of the present invention, there is provided a weighing unit provided in the hopper so that the mass of the granular material falling on the hopper from the supply device for supplying the granular material becomes a predetermined target measurement value. In the method for quantitative measurement of granular material for measuring the granular material, the preliminary measurement includes a step of performing preliminary measurement, and a step of performing final measurement so that the measurement value of the measurement means matches the target measurement value, In the step of measuring, the supply of the granular material by the supply device is stopped from the large supply operation state in which the supply amount of the granular material per unit time from the supply device is relatively increased. The amount of increase in the measured value from the stop to the end of dropping of the granular material is obtained as a first drop value, and the supply amount of the granular material per unit time from the supply device is relatively small. Small supply luck A step of performing the main measurement by stopping the supply of the granular material by the supply device from a state to obtain an increase in the measured value from the stop until the dropping of the granular material is finished as a second drop value. Then, the large supply operation is performed until the measured value reaches a first stop value that is a difference between a predetermined target measured value and a predetermined first reference value based on the first drop value, The small supply operation is performed until the measured value reaches a second stop value that is a difference between the target measured value and a predetermined second reference value based on the second drop value.

  According to such a configuration, a step of performing preliminary weighing and a step of performing main weighing are executed within one batch. Therefore, in the step of performing the main weighing, the large supply operation is performed until the first stop value that is the difference between the predetermined first reference value based on the first drop value obtained in the preliminary weighing step and the predetermined target measurement value. That is, it can be executed to the limit that can be supplied by the large supply operation. As a result, the measured value can be quickly brought close to the target measured value.

  Then, in the step of performing the main measurement, the small supply operation is performed from the state in which the measurement value is made close to the target measurement value by the large supply operation. Therefore, the time for performing the small supply operation is short. In addition, the small supply operation is executed up to a second stop value that is a difference between a predetermined second reference value based on the second drop value obtained in the preliminary weighing step and the target measured value. Therefore, the measured value can be made to substantially match the target measured value by the small supply operation. In addition, more accurate weighing can be performed in the small supply operation than in the large supply operation. Thereby, in the small supply operation, the measurement time can be shortened and extremely accurate measurement can be realized.

From the above, in the step of performing this measurement, based on the preliminary measurement mode, from the state where a large supply operation capable of realizing extremely quick measurement while ensuring high accuracy and a state in which the measurement time is shortened, Since the small supply operation capable of realizing accurate weighing is used in combination, extremely quick and accurate weighing can be realized.
In addition, in the case of the large supply operation, the first drop value as the drop value in the large supply operation is considered, and in the case of the small supply operation, the second drop value as the drop value in the small supply operation is considered. Thus, the precision of measurement is very high by setting the head value corresponding to each operation state. Further, the step of performing the preliminary weighing and the step of performing the main weighing are executed in one batch. Therefore, the weighing can be performed without using the weighing result of the previous batch, and quick and accurate weighing can be realized from the first batch.

Invention of Claim 5 WHEREIN: When the measurement of the said granular material is 1st batch in invention of Claim 4, it performs both the step which performs the said preliminary measurement, and the step which performs the said main measurement, When the measurement of the granular material is after the second batch, the step of performing the main measurement is performed without performing the step of performing the preliminary measurement.
According to such a configuration, when the first batch is weighed, the preliminary weighing is performed, so that the main weighing is performed from the state where a predetermined amount of the granular material is already stored in the hopper. Can do. Further, in the case of weighing after the second batch, the step of performing preliminary weighing can be omitted by using the first and second head drop values obtained in the step of performing preliminary weighing performed in the first batch. . Therefore, it is possible to quickly measure the granular material.

A sixth aspect of the invention is characterized in that, in the invention of the fourth or fifth aspect, a value obtained by multiplying the first drop value by a predetermined coefficient is used as the first reference value.
According to such a configuration, the first reference value can be set to an arbitrary value based on the first drop value. Therefore, supply error due to large supply operation can be considered.

As described above, according to the first aspect of the present invention, extremely quick and accurate weighing can be realized from the first batch.
According to invention of Claim 2, a granular material can be measured rapidly about each of 1st batch and 2nd batch and after.
According to the third aspect of the present invention, the supply error due to the large supply operation can be taken into consideration.

According to the invention of the fourth aspect, extremely quick and accurate weighing can be realized from the first batch.
According to the fifth aspect of the present invention, it is possible to quickly measure the granular material for each of the first batch and the second and subsequent batches.
According to the sixth aspect of the present invention, the supply error due to the large supply operation can be taken into consideration.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is an overall configuration diagram showing a metering and mixing apparatus as an embodiment of a powder and substance quantitative supply apparatus of the present invention.
In FIG. 1, the measuring and mixing apparatus 1 includes a supply hopper unit 2 and a measuring and mixing unit 3.

  The supply hopper unit 2 includes a plurality of supply hoppers 4 (when the supply hoppers 4 are distinguished from each other, they are referred to as a first hopper 4a, a second hopper 4b, a third hopper 4c, and a fourth hopper 4d). Yes. Each supply hopper 4 is connected to a raw material supply line 5 connected to a raw material tank (not shown) where powder particles are stored, and a suction line 7 connected to a suction blower 6.

The suction line 7 includes a switch valve unit 9 including a switch valve 8 provided corresponding to each supply hopper 4, a primary suction line 10 connecting the switch valve unit 9 and the suction blower 6, and each switch valve. A plurality of secondary suction lines 11 for connecting the unit 9 and the supply hoppers 4 are provided.
Further, filters 12 are provided on the upper side of the supply hopper 4.

  In order to pneumatically transport the granular material from each raw material tank to each supply hopper 4, the suction blower 6 is operated with the switch valve 8 corresponding to the supply hopper 4 to be pneumatically transported opened. Then, the granular material is selectively pneumatically transported to the supply hopper 4. That is, when the suction blower 6 is operated with the switch valve 8 corresponding to the supply hopper 4 to be pneumatically transported open, via the primary suction line 10, the switch valve unit 9, and the secondary suction line 11, The inside of the supply hopper 4 to be pneumatically transported is sucked. Thereby, the granular material stored in the raw material tank corresponding to the supply hopper 4 is pneumatically transported through the raw material supply line 5 connected to the supply hopper 4.

In addition, the air which conveyed the granular material to the supply hopper 4 is isolate | separated from the granular material by the filter 12 which consists of punching plates, Then, it passes through the secondary side suction line 11, the switch valve unit 9, and the primary side suction line 10. Then, the air is exhausted from the suction blower 6.
In this way, each supply hopper 4 temporarily stores the granular material that is pneumatically transported from each raw material tank. In addition, each supply hopper 4 stores the same type or different types of powder as appropriate depending on the purpose and application. For example, main materials (resin pellets), master batches, pulverized materials, additives, etc. Each of the supply hoppers 4 stored in the supply hopper 4 is set as a first hopper 4a, a second hopper 4b, a third hopper 4c, and a fourth hopper 4d in a weighing mode to be described later. The number of supply hoppers 4 is not limited to four, and may be one, or two, three, or five or more.

  Each supply hopper 4 is provided with a screw feeder 13 as a supply device for supplying powder particles. In addition, in this embodiment, although the structure which uses a screw feeder as a supply apparatus is demonstrated, if it can change the supply amount per unit time of a granular material, it will not be restricted to a screw feeder, for example, a rotary feeder, A slide gate or the like may be used. Each screw feeder 13 includes a supply path 14 connected to the corresponding supply hopper 4.

  A screw 15 is disposed inside a portion in the supply path 14 that extends straight upward or toward the supply port 17 and is rotated by a feed motor 16. When the screw 15 is rotated by driving the feed motor 16, the powder particles in each supply hopper 4 are sent to the supply path 14, and further, a metering hopper described later from a supply port 17 formed at one end of the supply path 14. Drop towards 21. The screw feeders 13 are arranged at equal intervals above the weighing hopper 21 so that the supply port 17 faces the center of the weighing hopper 21.

The weighing and mixing unit 3 includes a weighing unit 19 and a mixing unit 20 above the casing 18.
The weighing unit 19 includes a weighing hopper 21 as a hopper that receives the granular material supplied from each supply hopper 4, a load cell 22 as a weighing means that supports the weighing hopper 21, and the weighing hopper 21 to the mixing unit 20. And a discharge gate 23 for supplying the weighed granular material.

  The weighing hopper 21 is formed with a receiving port 24 for receiving powder particles at its upper end, and a discharge port 25 for discharging powder particles at its lower end. The discharge gate 23 is provided to open and close the discharge port 25 of the weighing hopper 21. The load cell 22 is provided so as to measure the mass of the weighing hopper 21 while supporting the weighing hopper 21. The mass of the granular material placed on the weighing hopper 21 is measured by the load cell 22 in a state where the mass of the weighing hopper 21, that is, the mass of the tare is canceled.

The mixing unit 20 includes a mixing casing 51, a stirring blade 28, a supply port 53 for supplying powder particles in the mixing casing 51 to the lower hopper 52, and a discharge gate 54 for opening and closing the supply port 53. Yes.
The powdered granular material discharged from the measuring unit 19 is supplied to the mixing casing 51. The stirring blade 28 is a drive shaft 32 that protrudes from the mixing casing 51 so that its axis extends in a direction perpendicular to the falling direction in which the powder particles fall from the measuring unit 19 in the mixing casing 51. And a blade 33 extending in the radial direction around the drive shaft 32, and the drive shaft 32 is driven by a stirring motor 34.

  As a result, the powder particles falling from the weighing unit 19 for each batch are mixed in the vertical direction by the blades 33, whereby the powder particles from the supply hoppers 4 are sufficiently mixed with each other. The granular material mixed by the mixing unit 20 falls from the supply port 53 to the lower hopper 52 when the discharge gate 54 is opened. The lower hopper 52 is provided with a level switch 29.

The level switch 29 is provided on the side wall of the lower hopper 52, and / or a prohibition signal transmission unit that transmits a supply prohibition signal (upper limit prohibition signal) when several batches of powder particles accumulate in the lower hopper 52, and / or A request signal transmission unit is provided that transmits a supply request signal (lower limit request signal) when the granular material of the lower hopper 52 is reduced by a predetermined amount or more.
The level switch 29 may be provided with two level switches, for example, a level switch that transmits an upper limit prohibition signal and a level switch that transmits a lower limit request signal, respectively, and in order to prevent overflow. One level switch may be provided and used as an interlock.

At the lower end of the lower hopper 52, a supply port 31 is provided for supplying powder particles in the lower hopper 52 to an external processing device 30 such as a molding machine.
The supply port 31 is formed in a cylindrical shape so as to protrude downward from the lower hopper 52, and an opening / closing gate 35 for opening and closing the supply port 31 is provided at the tip of the supply port 31.

  In such a metering / mixing device 1, for example, the feed motor 16 of each screw feeder 13, the opening / closing device of the load cell 22 and the discharge gate 23 of the metering unit 19, the level switch 29 of the mixing unit 20, the stirring motor 34, the discharge gate 54 opening / closing devices and an opening / closing device for the opening / closing gate 35 are connected to a controller unit 36 as control means, and these units are controlled by the controller unit 36.

  The controller unit 36 includes a CPU, RAM, ROM, and the like, and is provided with an operation unit 37 including a touch panel. By operating the operation unit 37 by the operator, the mass of the granular material supplied from each supply hopper 4 to the weighing hopper 21 can be set. More specifically, it is possible to set a target measurement value w1 as a target value of the mass of the granular material supplied from the first hopper 4a to the measurement hopper 21.

Similarly, the target measurement value w2 as the target value of the mass of the powder particles supplied from the second hopper 4b to the weighing hopper 21, and the target value of the mass of the powder particles supplied from the third hopper 4c to the measurement hopper 21 And a target measurement value w4 as a target value of the mass of the powder and granular material supplied from the fourth hopper 4d to the measurement hopper 21 can be set.
Next, the metering, mixing, and quantitative supply operations of the metering / mixing apparatus 1 configured as described above will be described. In this measuring and mixing apparatus 1, first, the powder particles stored in each supply hopper 4 are respectively put into the measuring hopper 21 and weighed, and in the measuring hopper 21, these are mixed with a mixture having a predetermined mixing ratio. After that, this is made into one batch and supplied to the mixing unit 20 for each batch. In this mixing unit 20, after collecting the granular material, the discharge gate 54 is opened and supplied to the lower hopper 52. A fixed amount is supplied from the supply port 31 of the hopper 52 to the external processing device 30.

One of the features of the present embodiment is that when the mass of the granular material supplied from each supply hopper 4 to the weighing hopper 21 is weighed by the load cell 22, the weighing time is as long as possible from the first batch of weighing. However, the accuracy is as high as possible.
In FIG. 2, the mass of the granular material supplied from each supply hopper 4 to the weighing hopper 21 is measured to become the corresponding target measurement values w1 to w4 (hereinafter, measuring the mass is simply referred to as weighing). FIG. 6 is a flowchart showing a flow of control of the controller unit 36 in the weighing process.

Referring to FIG. 2, when the weighing process is started by operating the operation unit 37 by the operator, it is first determined whether or not this weighing process is the first batch (S1). The number of batches is not reset to zero unless the components of the granular material put into each supply hopper 4 and the target measurement values w1 to w4 related to each supply hopper 4 are changed.
When it is determined that the weighing process is the first batch (S1: YES), the processing of S2 to S9 described later is performed as the weighing of the first batch. Specifically, the first hopper preliminary weighing (S2) for performing preliminary weighing on the powder particles of the first hopper 4a, the first hopper main weighing (S3) for performing final weighing on the powder particles of the first hopper 4a, the first 2nd hopper pre-weighing (S4) for preliminarily weighing the powder particles of the 2 hoppers 4b, 2nd hopper main weighing (S5) for performing the main weighing of the powder particles of the second hopper 4b, and the particles of the third hopper 4c The third hopper preliminary weighing (S6) for performing preliminary weighing on the body, the third hopper main weighing (S7) for performing final weighing on the powder particles of the third hopper 4c, and the preliminary weighing for the powder particles on the fourth hopper 4d. The fourth hopper preliminary measurement (S8) and the fourth hopper main measurement (S9) for performing the main measurement on the granular material of the fourth hopper 4d are performed in this order.

Thus, preliminary weighing and main weighing are performed for each supply hopper 4. In the flow chart shown in FIG. 2, the procedure in the case where four supply hoppers 4 are provided is shown, but the same procedure is used when there are more or fewer supply hoppers 4.
Regarding the first hopper preliminary weighing (S2), as shown in the flowchart in FIG. 3, when the preliminary weighing is started, first, the supply amount of the granular material per unit time by the screw feeder 13 of the first hopper 4a. A large supply operation is performed as a relatively large operation (S10). During the large supply operation, the feed motor 16 is driven so that the rotation speed of the feed motor 16 becomes relatively large. At this time, the mass of the granular material falling from the supply port 17 of the screw feeder 13 per unit time is relatively large.

  The large supply operation is continued until a predetermined first time T1 (for example, 3 seconds) elapses after the large supply operation is started (S11: NO). When the first time T1 has elapsed since the start of the large supply operation (S11: YES), the large supply operation is stopped by stopping the feed motor 16 (S12). From the start of the large supply operation to the moment when the feed motor 16 is stopped, for example, 100 g of powder particles are placed on the weighing hopper 21. That is, the increase Δw ′ of the measurement value W during execution of the large supply operation is 100 g.

It waits until predetermined | prescribed 2nd time T2 (for example, 3 second) passes after the large supply driving | operation is stopped (S13: NO). During this time, the entire amount of powder that has fallen freely between the supply port 17 and the weighing hopper 21 at the moment when the large supply operation is stopped is placed on the weighing hopper 21.
When the second time T2 elapses after the large supply operation is stopped (S13: YES), the first drop value wa is measured (S14).

  The first drop value wa refers to the mass of the granular material that has fallen freely between the supply port 17 and the weighing hopper 21 at the moment when the large supply operation is stopped. In other words, the first drop value wa is the measured value W from when the screw feeder 13 is stopped from the state where the large supply operation is performed until the dropping of the granular material to the weighing hopper 21 is completed. An increase in the amount. The first drop value wa is, for example, 130 g.

  Next, a predetermined first reference value wa '(also referred to as a pre-quantification value) based on the first drop value wa is set (S15). The first reference value wa ′ is set so as to be larger than the first drop value wa in consideration of the supply error in the large supply operation. The first reference value wa ′ is set to a predetermined coefficient α ( For example, it is set to a value multiplied by 1.2). In the present embodiment, the first reference value wa ′ = α × wa = 1.2 × 130 g = 156 g.

  After the first reference value wa 'has been set, a small supply operation is performed as an operation in which the supply amount of the granular material per unit time by the screw feeder 13 is relatively small (S16). During the small supply operation, the feed motor 16 is driven so that the rotation speed of the feed motor 16 becomes relatively small. At this time, the mass of the granular material per unit time falling from the supply port 17 of the screw feeder 13 is relatively small.

  The small supply operation is continued until a predetermined third time T3 (for example, 3 seconds) elapses after the small supply operation is started (S17: NO). When the third time T3 elapses after the small supply operation is started (S17: YES), the small supply operation is stopped by stopping the feed motor 16 (S18). From the start of the small supply operation to the moment when the feed motor 16 is stopped, for example, 30 g of powder particles are placed on the weighing hopper 21. That is, the increase Δw ″ of the measurement value W during the small supply operation is 30 g.

It waits until predetermined | prescribed 4th time T4 (for example, 3 second) passes after the small supply driving | operation is stopped (S19: NO). During this time, the entire amount of the powder that has fallen freely between the supply port 17 and the weighing hopper 21 at the moment when the small supply operation is stopped is placed on the weighing hopper 21.
When the fourth time T4 elapses after the small supply operation is stopped (S19: YES), the second drop value wb is measured (S20). The second drop value wb refers to the mass of the granular material that has fallen freely between the supply port 17 and the weighing hopper 21 at the moment when the small supply operation is stopped. In other words, the second drop value wb is an increase in the measured value W from when the screw feeder 13 is stopped from the state where the small supply operation is performed until the fall of the granular material ends. The second drop value wb is, for example, 20 g.

  Next, a predetermined second reference value wb '(also referred to as a drop value) based on the second drop value wb is set (S21). The second reference value wb 'is obtained by multiplying the second drop value wb by a predetermined coefficient β. In the present embodiment, by setting the coefficient β = 1, the second reference value wb ′ is set to be the same as the second drop value wb. That is, in the present embodiment, the second reference value wb ′ = the second drop value wb = 20 g.

  From the above, the first reference value wa ′ (156 g in the present embodiment) and the second reference value wb ′ (20 g in the present embodiment) are set. Also, by one preliminary weighing process, the measured value W as the mass of the granular material in the weighing hopper 21 is set to the preliminary measured value wc = the increase Δw ′ of the measured value W during the large supply operation + the first drop value wa +. The increase in the measured value W during the small supply operation is increased by Δw ″ + the second drop value wb (= 100 g + 130 g + 30 g + 20 g = 280 g).

In the first batch of the weighing mode, when the first hopper preliminary weighing (S2) is completed, the first hopper 4a is already filled with powder particles having a mass corresponding to the preliminary weighing value wc from the first hopper 4a. Hopper main measurement (S3) is performed.
Specifically, referring to the flowchart of FIG. 4 and the graph of FIG. 5, when the main measurement of the granular material supplied from the first hopper 4 a is started, first, the rotational speed of the feed motor 16 is changed. The feed motor 16 is driven so as to be relatively large. Thereby, the large supply operation is started (S22).

  The mass of the granular material in the weighing hopper 21, that is, the measured value W, increases more rapidly from the preliminary measured value wc (in the present embodiment, the above-described 280 g). In the large supply operation, the measurement value W is a difference between the target measurement value w1 and the first reference value wa ′. The first stop value wd (measurement value W = first stop value wd = target measurement value w1−first reference value). It continues until it reaches the value wa ′ (in this embodiment, 500 g−156 g = 344 g) (S23: NO).

  The first reference value wa 'is a value (wa'> wa + wb) larger than the sum of the first drop value wa and the second drop value wb. This is because, after the driving of the screw feeder 13 in the first hopper 4a is stopped at the first stop value wd, further, the granular material corresponding to at least the first drop value wa and the granule corresponding to the second drop value wb. This is because the body is supplied to the weighing hopper 21.

  When the measured value W becomes the first stop value wd (S23: YES), the drive of the feed motor 16 is stopped and the large supply operation is stopped (S24). Wait until a predetermined fifth time T5 (for example, 3 seconds) has elapsed since the stop of the large supply operation (S25: NO), and almost all of the granular material falling from the supply port 17 is transferred to the weighing hopper 21. Wait for it to appear. As the fifth time T5 elapses from the large supply operation, the measured value W becomes the first stop value wd + the first drop value wa (344 g + 130 g = 474 g in the present embodiment).

Next, the feed motor 16 is driven so that the rotation speed of the feed motor 16 becomes relatively small, whereby the small supply operation is started (S26).
Thereby, the measured value W further increases from the first stop value wd + the first drop value wa (474 g in the present embodiment). At this time, the rate of increase of the measured value W per unit time is smaller than that in the large supply operation, and the measured value W increases slowly.

  In the small supply operation, the measured value W is a difference between the target measured value w1 and the second reference value wb ′ (second drop value wb), the second stop value we (measured value W = second stop value we = target). It continues until it reaches the measured value w1−second reference value wb ′ (in this embodiment, 500 g−20 g = 480 g) (S27: NO). When the measured value W becomes the second stop value we (480 g in the present embodiment) (S27: YES), the drive of the feed motor 16 is stopped and the small supply operation is stopped (S28).

  After the small supply operation is stopped, the system waits until a predetermined time T6 (3 seconds in the present embodiment) elapses (S29: NO). During this time, the powder particles falling from the supply port 17 toward the weighing hopper 21 when the small supply operation is stopped are further placed on the weighing hopper 21. As a result, the measured value W becomes the second stop value we + the second drop value wb (480 g + 20 g = 500 g in the present embodiment), that is, the target measured value w1, and the target measured value w1 from the first hopper 4a to the measuring hopper 21. A granular material having a mass of a minute is supplied.

  Next, it is confirmed that the measured value W matches the target measured value w1 within an allowable error range (for example, ± several g) (S30). Thereafter, in preparation for preliminary weighing and main weighing of the next supply hopper 4, the weighing value W, the first drop value wa, the first reference value wa ′, the first stop value wd, the second drop value wb, the second reference value The value wb ′, the second stop value we, and the like are stored in the memory and reset to zero (S31), and the measurement ends.

Referring to FIG. 2, by performing the first hopper preliminary weighing (S2) and the first hopper main weighing (S3) as described above, the powder particles falling from the first hopper 4a to the weighing hopper 21 are collected. Weighing is performed so that the mass becomes the target weighing value w1.
The second hopper preliminary weighing (S4) and the second hopper main weighing (S5) are performed in the same flow as the first hopper preliminary weighing (S2) and the first hopper main weighing (S3). The third hopper preliminary weighing (S6) and the third hopper main weighing (S7) are performed by the same flow as the first hopper preliminary weighing (S2) and the first hopper main weighing (S3). Further, the fourth hopper preliminary weighing (S8) and the fourth hopper main weighing (S9) are performed by the same flow as the first hopper preliminary weighing (S2) and the first hopper main weighing (S3). Therefore, the detailed description of each flow of S4 to S9 is omitted.

  As described above, when the preliminary weighing and the main weighing are completed for each of the supply hoppers 4, the granular material having a mass corresponding to the target weighing value w1 is supplied from the first hopper 4 a to the weighing hopper 21. The second hopper 4b is in a state in which a granular material having a mass corresponding to the target measured value w2 is supplied, and the third hopper 4c is in a state in which a granular material having a mass corresponding to the target measured value w3 is supplied. The fourth hopper 4d is in a state where a granular material having a mass corresponding to the target measured value w4 is supplied.

These powder particles are dropped into the mixing unit 20 from the outlet 25 of the weighing hopper 21 as one batch of powder particles.
When the first batch is completed and the second and subsequent batches are measured (S1: NO), the preliminary measurement is not performed and the main measurement is performed. Specifically, the first hopper main weighing (S32) is obtained by the first hopper preliminary weighing (S2) of the first batch, and is stored in the memory of the controller unit 36. The first drop value wa and the first reference value wa ', The second drop value wb, the second reference value wb', and the first stop value wd and the second stop value we obtained in the first hopper main measurement (S3) of the first batch as they are, one batch Weigh in the same flow as the first hopper main weighing (S3) of the eyes.

Note that at the start of the first hopper main measurement after the second batch, the powder from the first hopper 4a is not placed on the measurement hopper 21, and the mass of the powder from the first hopper 4a is zero. Is different from the first hopper main weighing (S3) of the first batch.
That is, in the case of the first batch in FIG. 5, the main measurement is started from the time when the measurement value W for the powder from the first hopper 4a is the preliminary measurement value wc (W = wc). In the second and subsequent batches, the main measurement is started when the measurement value W of the granular material from the first hopper 4a is zero (W = 0).

  When the first hopper main measurement (S32) is completed in the second and subsequent batches, then the second hopper main measurement (S33), the third hopper main measurement (S34), and the fourth hopper main measurement (S35) are performed. , In order. The second hopper main measurement (S33), the third hopper main measurement (S34), and the fourth hopper main measurement (S35) are performed in the same flow as the first hopper main measurement (S33). Detailed description is omitted.

  In this way, in the second and subsequent batches as well, in each batch, the weighing hopper 21 is supplied with the granular material having the mass corresponding to the target measured value w1 from the first hopper 4a. The hopper 4b is in a state in which a granular material having a mass corresponding to the target measured value w2 is supplied, and the third hopper 4c is in a state in which a granular material having a mass corresponding to the target measured value w3 is supplied, and the fourth hopper 4d. Is in a state where a granular material having a mass of the target measured value w4 is supplied.

These powder particles are dropped into the mixing unit 20 from the outlet 25 of the weighing hopper 21 as one batch of powder particles. And the granular material mixed by the mixing unit 20 is supplied to the processing apparatus 30 from the supply port 31 of the lower hopper 52.
As described above, according to the present embodiment, the preliminary weighing mode and the main weighing mode are executed in one batch. Therefore, in each main measurement mode, the large supply operation is a first stop value that is a difference between the first reference value wa ′ based on the first drop value wa obtained in the preliminary measurement mode and the corresponding target measurement values w1 to w4. The process can be executed up to wd, that is, the limit that can be supplied by the large supply operation. As a result, the measurement value W can be quickly brought close to the corresponding target measurement values w1 to w4.

  In each main measurement mode, the small supply operation is performed from the state in which the measurement value W is set to a value close to the corresponding target measurement values w1 to w4 by the large supply operation. Therefore, the time for performing the small supply operation is short. Further, the small supply operation is executed up to the second stop value we which is the difference between the second reference value wb ′ based on the second drop value wb obtained in the preliminary weighing mode and the corresponding target weighing values w1 to w4. . Further, the second drop value wb and the second reference value wb ′ are set to the same value. Therefore, by the small supply operation, the measurement value W can be set to the second stop value we + the second reference value wb ′ = the second stop value we + the second drop value wb, and almost completely matches the corresponding target measurement values w1 to w4. Can be made. In addition, more accurate weighing can be performed in the small supply operation than in the large supply operation. Thereby, in the small supply operation, the measurement time can be shortened, and extremely accurate measurement can be realized.

As described above, each main weighing mode is extremely accurate based on the pre-weighing mode from the large supply operation that can achieve extremely quick weighing while ensuring high accuracy and the state that the weighing time is shortened. Therefore, extremely fast and accurate weighing can be realized.
Further, in the case of the large supply operation, the first drop value wa as the drop value in the large supply operation is considered, and in the case of the small supply operation, the second drop value wb as the drop value in the small supply operation is considered. Yes. Thus, the precision of measurement is very high by setting the head value corresponding to each operation state. Further, the preliminary weighing mode and the main weighing mode are executed in one batch. Therefore, the weighing can be performed without using the weighing result of the previous batch, and quick and accurate weighing can be realized from the first batch.

Further, both the preliminary weighing mode and the main weighing mode are executed at the time of the first batch weighing in the weighing unit 19, and the main weighing mode is executed without executing the preliminary weighing mode at the second batch or later. ing.
With such control, since the preliminary weighing is performed at the time of the first batch weighing, the main weighing is performed from the state in which the powders corresponding to the preliminary weighing value wc are already stored in the weighing hopper 21. Rapid weighing can be performed. Further, when weighing after 2 batches, by using the first drop value wa, the first reference value wa ′, the second drop value wb and the second reference value wb ′ obtained in the preliminary weighing mode of the first batch. The preliminary weighing mode can be omitted. Therefore, it is possible to quickly measure the granular material.

Further, a value obtained by multiplying the first drop value wa by a predetermined coefficient α is set as a first reference value wa ′. In this way, the first reference value wa ′ can be set to an arbitrary value based on the first drop value wa. Therefore, supply error due to large supply operation can be considered.
A value obtained by multiplying the second drop value wb by a predetermined coefficient β is set as a second reference value wb ′. In this way, the second reference value wb ′ can be set to an arbitrary value based on the second drop value wb. Therefore, supply errors due to the small supply operation can be taken into account.

The present invention is not limited to the contents of the above-described embodiment, and various modifications can be made within the scope of the claims.
For example, in the preliminary weighing mode, instead of the configuration in which the large supply operation is stopped when T1 seconds have elapsed from the start of the large supply operation, the measurement value W has increased by a predetermined value (for example, 100 g) after the large supply operation has started. Sometimes, the large supply operation may be stopped.

Similarly, in the preliminary weighing mode, instead of the configuration in which the small supply operation is stopped after T3 seconds have elapsed from the start of the small supply operation, the measurement value W increases by a predetermined value (for example, 30 g) after the large supply operation is started. When this happens, the small supply operation may be stopped.
Further, in each of the preliminary measurement mode and the main measurement mode, one type of small supply operation is performed. However, two or more types of small supply operations with different supply amounts of granular material per unit time are performed. May be. In this case, in this measurement mode, the supply amount of the granular material per unit time can be reduced more finely, and the measurement accuracy can be further increased.

Further, in each of the preliminary weighing modes, the small supply operation may be executed first, and then the large supply operation may be executed.
In the present embodiment, a relatively small metering and mixing device has been described as an example. However, the present invention is not limited to such a relatively small metering and mixing device, and other powder particles such as a large metering and mixing device. You may apply to the batch type metering and mixing apparatus which mixes a body.

It is a whole block diagram which shows the measurement mixing apparatus as one Embodiment of the fixed supply apparatus of the granular material of this invention. It is a flowchart which shows the flow of control of a controller unit in the measurement process which measures so that the mass of the granular material supplied from each hopper to a measurement hopper may become a corresponding target measurement value. It is a flowchart which shows the flow of control of the controller unit in a preliminary | backup measurement mode. It is a flowchart which shows the flow of control of the controller unit in this measurement mode. It is a graph for demonstrating the relationship of the measurement value in this measurement mode.

Explanation of symbols

1 Metering and mixing device (quantitative supply device)
13 Screw feeder (supply device)
17 Supply port 19 Weighing unit 21 Weighing hopper (hopper)
22 Load cell (measuring means)
36 Controller unit (control means)
W measurement value w1, w2, w3, w4 target measurement value wa first drop value wa 'first reference value wb second drop value wb' second reference value wd first stop value we second stop value α predetermined coefficient

Claims (6)

A supply device that includes a supply port for supplying powder particles and supplies the powder particles from the supply port;
A hopper for storing the powder particles dropped from the supply port, and a weighing unit including a weighing means for measuring the mass of the powder particles in the hopper;
Control means connected to the weighing means and controlling the supply device,
The control means can execute the preliminary weighing mode and the main weighing mode in order,
In the preliminary metering mode, the control means stops the supply device by stopping the supply device from a large supply operation state in which the supply amount of the granular material per unit time by the supply device is relatively large. The amount of increase in the measured value of the measuring means from the time the powder is dropped to the end is obtained as a first drop value, and the supply amount of the powder per unit time by the supply device is relatively reduced. By stopping the supply device from the small supply operation state, the increase in the measured value from the stop to the end of the dropping of the granular material is obtained as a second drop value,
In the main measurement mode, the control means is configured to increase the measurement value until the measurement value reaches a first stop value that is a difference between a predetermined target measurement value and a predetermined first reference value based on the first drop value. The supply operation is executed, and then the small supply operation is executed until the measured value becomes a second stop value that is a difference between the target measured value and a predetermined second reference value based on the second drop value. An apparatus for quantitatively supplying powder particles, characterized in that:   The control means executes both the preliminary weighing mode and the main weighing mode when weighing the first batch in the weighing unit, and the preliminary weighing mode when weighing after the second batch in the weighing unit. The apparatus for quantitatively supplying powder particles according to claim 1, wherein the main measurement mode is executed without executing the operation.   The powder supply unit according to claim 1 or 2, wherein the control unit sets a value obtained by multiplying the first drop value by a predetermined coefficient as the first reference value. Powder for measuring the powder using a measuring means provided in the hopper so that the mass of the powder falling to the hopper from the supply device for supplying the powder becomes a predetermined target measurement value. In the quantitative weighing method of the body,
Preliminarily weighing, and performing the main weighing so that the weighing value of the weighing means matches the target weighing value,
In the preliminary weighing step, the supply of the granular material by the supply device is stopped from a large supply operation state in which the supply amount of the granular material per unit time from the supply device is relatively increased. Thus, the increase in the measured value from the stop to the end of the dropping of the granular material is obtained as a first drop value, and the supply amount of the granular material per unit time from the supply device is relatively By stopping the supply of the granular material by the supply device from the small supply operation state which is reduced to a small value, the increase in the measured value from the stop to the end of the dropping of the granular material is set as the second drop value. Seeking
In the step of performing the main measurement, the large supply operation is performed until the measurement value becomes a first stop value that is a difference between a predetermined target measurement value and a predetermined first reference value based on the first drop value. And then performing the small supply operation until the measured value reaches a second stop value that is a difference between the target measured value and a predetermined second reference value based on the second drop value. A quantitative measurement method for powder particles. When the powder is weighed in the first batch, both the preliminary weighing step and the main weighing step are performed,
5. The granular material according to claim 4, wherein when the powder is weighed after the second batch, the step of performing the main weighing is performed without performing the step of performing the preliminary weighing. 6. Quantitative weighing method.   6. The method for quantitative measurement of granular material according to claim 4, wherein a value obtained by multiplying the first drop value by a predetermined coefficient is used as the first reference value.

Images