JPH08278188A - Quantitative charging devicee - Google Patents

Abstract

PURPOSE: To provide a quantitative charging device that is able to charge a measured material being varied in bulk density in a quantitative manner accurately and speedily, and further making wide range and trace amount of weight adjustments achievable. CONSTITUTION: This charging device is provided with a large charging storage tank 1 and four adding storage tanks 4a to 4d of 1:2:4:8 in volume ratio, and measured materials are fully filled up in these storage tanks 1 and 4a to 4d. An extent of volume in the large storage tank 1 should be set to be smaller than the target weight and so as to make the measured materials in weight approximating to this target weight storable. The measured materials in the large charging storage tank 1 are measured as large charging weight by a load cell 7, and weight of the measured materials in these four adding storage tanks 4a to 4d is found out by calculation from bulk specific gravity is sought by large charging weight and volume, then a proper combination of these adding storage tanks 4a to 4d is selected so as to become nearest to insufficient weight. The selected materials in the adding storage tanks are charged into a vessel 10 via a chute 9 together with the measured materials in the large charging storage tank 1. In consequence, since this bulk specific gravity of the measured material is sought, the measured materials being varied in bulk density can be quantitatively filled up accurately and speedily.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quantitative filling apparatus for filling a storage tank having a predetermined volume with an object to be weighed whose bulk density changes and performing quantitative filling. By providing multiple additional storage tanks, calculate the weight of the objects to be weighed in each additional storage tank from the bulk density obtained based on the volume of the large input storage tank and the weight of the objects to be weighed. The present invention relates to a quantitative filling device that selects and discharges a combination of the nearest addition storage tanks.

[0002]

2. Description of the Related Art Fixed-quantity filling of powder and granules has been carried out for a long time, and in that, weighing, that is, volume measurement, has been widely adopted for a long time. However, volumetric measurement was later replaced by weight. The main reason for this is the need for more accurate weighing. Typical examples thereof include chemical compounds. It has been a problem that has not been so important in measuring agricultural products such as rice and wheat since ancient times. A typical example of a quantitative filling device for powder and granules, which is currently mainly used, is shown in FIG.
Shown in

In the quantitative filling device of FIG. 4, the target weight is 10
Set with the 0% setter 51, set 90% of the target weight as the cut value with the cut value setter 52, and set the weighing hopper 53.
While weighing the object to be weighed. In this apparatus, in order to shorten the weighing time as much as possible, the amplitude of the feeding feeder 55 is increased up to 90% of the predetermined amount to increase the carrying capacity, so-called large loading (also called large loading, 90% loading, etc.). )I do. When the filling amount reaches about 90%, the control device 56 reduces the amplitude of the feeding feeder 55,
The remaining small amount of 10% is charged, and when 100% is reached, the charging is stopped.

This small amount injection is also called small injection. When the charging is completed, the container (not shown) is filled with the objects to be weighed from the lower portion of the weighing hopper 53. This type of quantitative filling device performs weighing while charging, and has a problem that the filling speed cannot be increased.

In order to solve this problem, a quantitative filling device which improves the filling speed is disclosed in, for example, Japanese Patent Laid-Open No. 50-120.
It is disclosed in Japanese Patent No. 660. In this type of quantitative filling device, an object to be weighed that is smaller than the target weight and close to the target weight is stored in a large-input storage tank, and a plurality of different volumes for compensating for the shortage that does not meet the target weight. An auxiliary tank (sub-quantitative device) is provided. Then, in this device, the shortage weight is obtained by subtracting the weight of the object to be weighed in the large input storage tank from the target weight, and one auxiliary tank closest to the shortage weight is selected. By providing such an auxiliary tank, it is possible to fill the object to be weighed with a weight close to the target weight. In addition, since the quantitative filling device does not perform the weighing while charging, the filling speed can be increased.

[0006]

However, in the quantitative filling device of the type described in the above publication, since the weight measuring device is provided in each auxiliary tank, the cost of the quantitative filling device is high because the measuring device is expensive. There is a problem that is high. In order to avoid this increase in cost, it is possible to use a structure in which the measuring device is disabled. In this case, the bulk density of the object to be weighed is calculated in advance, and the weight of the object to be weighed in each auxiliary tank is regarded as constant, and the insufficient weight is replenished.

However, depending on the object to be weighed, the bulk density may change over time, or the bulk density may change for each manufacturing lot. In such a case, there is a problem that the above-mentioned quantitative filling device, which regards the bulk specific gravity of the object to be weighed as constant, cannot perform quantitative filling accurately. Further, in the above-mentioned type of quantitative filling device, since only one auxiliary tank is used for supplementing the insufficient weight, there is a problem that the weight cannot be adjusted in a wide range and in a minute amount.

The present invention has been made in view of the above prior art, and an object of the present invention is to enable accurate and high-speed filling even when the bulk density of the object to be weighed changes. Moreover, it is an object of the present invention to provide a quantitative filling device capable of adjusting a wide range and a very small amount of weight.

[0009]

Determination filling apparatus of the present invention SUMMARY OF THE INVENTION is less than the target weight W _o, and a large input reservoirs having a volume V for reserving the objects to be weighed weight close to the target weight W _o, A plurality of addition storage tanks having a predetermined volume for storing the objects to be weighed for additional charging, a weighing means for measuring the weight of the objects to be weighed introduced into the large input tank as a large input weight W _a , and the target weight W _o the calculated as the difference W _o shortage -W _a weight W _b of the large-on weight W _a, obtaining a bulk density d of the objects to be weighed by dividing the full flow weight W _a in volume V of the large input reservoirs and At the same time, the weight of the object to be weighed in each addition storage tank is obtained by multiplying the volume of each addition storage tank and the bulk density d, and the combination of the addition storage tanks that is closest to the insufficient weight W _b is selected, The objects to be weighed in the selected addition storage tank are stored in the large input storage tank. Characterized by comprising a control means for performing control so as to discharge with objects to be weighed.

Further, at least some of the additional storage tanks may have the same volume.

The volume ratio of at least some of the additional storage tanks is

[0012]

[Equation 2]

The configuration may be

Further, the positive real number s = 2 can be adopted.

[0015]

In the quantitative filling device of the present invention, a large-charge storage tank for performing large-scale injection and a plurality of additional storage tanks for performing additional injection to supplement the large-scale injection are provided. Large input storage volume V
It is set a target weight W _o from small and the weight of the objects to be weighed close to this target weight W _o so as to reservoir.
Further, the addition storage tank is provided for dividing and storing the addition object to be weighed into a plurality of different volumes. The objects to be weighed can be added to the large input storage tank and each addition storage tank almost at the same time.

The weight of the object to be weighed put into the large input storage tank is weighed by the weighing means as the large input weight W _a . No weighing means is provided in each additional storage tank.

The control means subtracts the large input weight W _a measured by the measuring means from the target weight W _o W _o -W.
_a is determined as the insufficient weight W _b . Since the volume V of the large input storage tank is set so that the objects to be weighed having a weight smaller than the target weight W _o are stored, the value of the insufficient weight W _b is always a positive value. Next, the control means controls the bulk specific gravity d of the object to be weighed.
Perform the operation to obtain. That is, the bulk specific gravity d is obtained by dividing the large input weight W _a by the volume V of the large input storage tank. Next, the control means obtains the weight of the object to be weighed in each addition storage tank by multiplying the volume of each addition storage tank by the bulk density d. Then, the control means selects the combination of the addition storage tanks that is closest to the shortage weight W _b based on the weight of the measurement objects in each addition storage tank, and throws in a large amount of the measurement object in the selected addition storage tank. Control is performed so that the objects to be weighed in the storage tank are discharged.

As described above, by obtaining the bulk specific gravity d for each weighing, it is possible to carry out the quantitative filling with high accuracy applied to the change of the bulk specific gravity of the objects to be weighed without providing the weighing means in each addition storage tank. It will be possible. In addition, the shortage weight W _b ,
The calculation of the bulk specific gravity d of the object to be weighed and the weight of the object to be weighed in each additional storage tank and the selection of the combination of the additional storage tanks that are closest to the shortage weight W _b are performed immediately using a computer or the like. Therefore, high-speed filling is possible.

In the above structure, at least a part of the additional storage tanks may have the same volume, and at least m (m = the number of additional storage tanks) of the additional storage tanks. The volume ratio may be configured so as to satisfy the following general formula.

[0020]

(Equation 3)

Here, s is a positive real number, and 0 <k ≦ m.

In the above formula 2, s may be an integer or a decimal as long as it is a positive number, but if s = 2,
The volume ratio of the additional storage tank is 1: 2: 4: 8 ..., which makes it possible to adjust the weight in a wide range and in a minute amount.

[0023]

Embodiments of the present invention will be described in more detail with reference to the drawings.

FIG. 1 shows a schematic structure of a quantitative filling device according to an embodiment of the present invention. The quantitative filling device of the present embodiment is used to fill a predetermined container such as a box or a bag with a target weight W _o to be weighed, and a large input storage tank 1 for storing the target to be weighed. 4 additional storage tanks 4a, 4b, 4c
And 4d. Volume V of the large input reservoirs 1 is set to the target weight W _o from small and the weight close to the target weight W _o objects to be weighed so as to reservoir. An object to be weighed is charged from the charging device 11 into the large input storage tank 1 and the four addition storage tanks 4a to 4d at substantially the same time, for example, by scraping. The large input storage tank 1 is provided with a load cell 7,
The weight of the object to be weighed into the large-load storage tank 1 is measured by the load cell 7. No load cell is provided in the four addition storage tanks 4a to 4d. The output from the load cell 7 is input to a control device having a circuit shown in FIG. 2 described later.

A gate 8 for discharging the objects to be weighed is provided at the bottom of the large input storage tank 1, and the addition storage tank 4 is also provided.
Four gates 6 that are independently opened and closed are provided in a to 4d. Large input storage tank 1 and additional storage tanks 4a to 4d
The objects to be weighed inside the container 1 such as boxes and bags through the chute 9.
It is discharged to 0. The opening and closing of the gate 8 and the four gates 6 described above are performed under the control of the above-mentioned control device.

The volume ratio of the additional storage tanks 4a to 4d is s
^In the formula of ^k−1 (s is a positive real number, k ≦ m, m = number of additional storage tanks), the ratio where s = 2 and m = 4, that is, 1: 2:
It is 4: 8.

As shown in the block circuit diagram of FIG. 2, the output from the load cell 7 that weighs the object to be weighed into the large input storage tank 1 is amplified by the amplifier 21 and input to the A / D converter 23. To be done. The A / D converter 23 converts the input analog data into digital data and enables processing by a CPU (central processing unit) 24. CPU
At 24, processing is performed according to a program stored in a ROM (read-only memory) 25. At that time, RA
The M (random access memory) 26 is temporarily used. Data such as the target weight W _o , the volume V of the large input storage tank 1 and the volumes of the addition storage tanks 4a to 4d are input via the keyboard 27 and stored in the nonvolatile RAM 30. CPU2
The opening / closing of the gate 8 and the four gates 6 based on the result of the processing in 4 is controlled via the input / output 28. The display 29 is the weight of the object to be weighed, the nonvolatile RAM 30.
The setting value etc. are displayed.

In the apparatus of this embodiment, fixed quantity filling is performed according to the flow chart of FIG. First, in step 32, the container 10 is set under the chute 9 and then in step 3
At 3, the objects to be weighed are charged from the charging device 11 into the large input storage tank 1 and the four addition storage tanks 4a to 4d. In step 34, the total weight of the objects to be weighed put into the large input storage tank 1 is measured by the load cell 7 as the large input weight W _a .

Next, in step 35, the insufficient weight W _d = W _a
−W _o is calculated, and at the same time, the bulk density d of the object to be measured is calculated. Bulk density d is (large input weight W _a ) /
It is obtained by the calculation of (volume V of large input storage tank 1). Next, in step 36, each of the additional storage tanks 4a to 4 is added to the bulk density d.
By multiplying by the volume of d, each addition storage tank 4a-4d
The weight of the objects to be weighed stored inside is obtained. Further, in step 37, each of the additional storage tanks 4a-
Based on the weight of the objects to be weighed inside 4d, combinations comes closest addition reservoir 4a~4d is selected insufficient weight W _d obtained in step 35. In step 38, the objects to be weighed in the selected addition storage tank are discharged together with the objects to be weighed in the large input storage tank 1 and filled in the container 10. Further, step 39
At, the filled container is replaced with an empty container, and the process returns to step 32 and the weighing is repeated.

In the quantitative filling device of this embodiment, since the bulk specific gravity d is required for each weighing, high accuracy applied to the change of the bulk specific gravity of the objects to be weighed without providing a weighing means in each of the additional storage tanks 4a to 4d. It is possible to perform a fixed amount of filling.

Further, in the apparatus of this embodiment, the additional storage tank 4a
Since the volume ratio of ~ 4d is 1: 2: 4: 8, the weight of the object to be weighed stored in the minimum addition storage tank 4a is 1
This means that the object to be weighed for adding up to 15 times is prepared. Therefore, the weight of the object to be weighed can be adjusted in a wide range, and the weight can be finely adjusted. In addition, the CPU 24 quickly selects the combination of the shortage weight W _d , the bulk specific gravity d, and the weight of the objects to be weighed in each of the additional storage tanks 4a to 4d, and the selection of the combination of the additional storage tanks that is closest to the shortage weight W _d. As it is done, the filling speed is very fast.

In the above embodiment, the case where four additional storage tanks are provided has been described, but the present invention is not limited to this, and any number can be used. Further, in each of the above embodiments, the case where the positive integer s is set to 2 has been described, but the present invention is not limited to this, and it may be an integer other than this or may be a decimal. The volume of the additional storage tank may be the same.

[0033]

In the quantitative filling device of the present invention, the bulk density of the object to be weighed is determined every time based on the volume of the large-charge storage tank and the weight of the object to be weighed. Even in the case of an object to be weighed that changes over time or for each manufacturing lot, it is possible to perform highly accurate quantitative filling without providing a weighing means in each addition storage tank. In addition, in the quantitative filling device of the present invention, since the addition storage tank that is closest to the insufficient weight is selected from the plurality of addition storage tanks, the weight can be adjusted in a wide range, and the weight can be finely adjusted. ing. Further, the calculation of the insufficient weight, the bulk specific gravity of the object to be weighed, and the weight of the object to be weighed in each additional storage tank, and the selection of the combination of the additional storage tanks that are closest to the insufficient weight can be performed at high speed by using a computer or the like. Therefore, the filling speed can be increased.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a quantitative filling device according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram which constitutes a control means in the filling device of FIG.

FIG. 3 is a flowchart showing a quantitative filling method performed by the filling device of FIG.

FIG. 4 is a schematic configuration diagram of a conventional quantitative filling device including a vibrating feeder.

[Explanation of symbols]

 1 Large input storage tank 4a-4d Additional storage tank 6,8 Gate 7 Load cell 9 Chute 10 Container 11 Input device

Claims (4)

[Claims] 1. A smaller than the target weight W _o, and a predetermined volume of reservoir and a large input reservoirs having a volume V for reserving the objects to be weighed weight close to the target weight W _o, the objects to be weighed for addition-on a plurality of summing reservoir of the difference W _o of a metering means for metering the weight of the objects to be weighed which the thrown into a large input reservoirs as full flow weight W _a, and the target weight W _o and said full flow weight W _a -W
_a is calculated as the insufficient weight W _b , the large input weight W _a is divided by the volume V of the large input storage tank, and the bulk density d of the object to be weighed is calculated.
The weight of the object to be weighed in each addition storage tank is obtained by multiplying the volume of each addition storage tank and the bulk density d, and a combination of the addition storage tanks that is closest to the insufficient weight W _b is selected. And a control means for controlling such that the object to be weighed in the selected addition storage tank is discharged together with the object to be weighed in the large input storage tank. 2. The quantitative filling device for an object to be weighed according to claim 1, wherein at least some of the additional storage tanks have the same volume. 3. The volume ratio of at least some of the additional storage tanks is expressed by the following formula: The quantitative filling device for the object to be weighed according to claim 1, wherein 4. The quantitative filling device according to claim 3, wherein the positive real number s = 2.