JPH0716830A - Continuous kneading powder discharge amount controlling method - Google Patents

Abstract

PURPOSE:To continuously supply kneading liquid by a method wherein a powder reduction amount with time is monitored, an actual kneading ratio is calculated by the powder reduction amount and a momentary liquid flow rate, and a powder discharge amount is corrected so that the actual kneading ratio coincides with a target kneading ratio. CONSTITUTION:A kneading powder supply device is composed of a first device A and a second device B serially juxtaposed. A momentary water flow rate measured by a flow meter A1 and a powder reduction amount in a weight sensor converter A5 are arithmetically operated. If the result is different from a target kneading ratio, a correction signal is outputted from an operation controller A6 to a motor controller A4 to control a powder discharge amount to make the result coincide with the target kneading ratio. The powder is supplied to a kneading machine A9. A momentary flow rate of the mixed liquid is monitored by a flow meter B1. A discharge amount of a powder supply machine B3 is calculated by a weight sensor converter B5 and inputted to the operation controller A6. A rotating speed of a motor B8 is changed to accomplish a target discharge amount. in this manner, powder can be discharged and kneaded correspondingly to liquid continuously supplied. A kneading time is reduced, and a working efficiency is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the discharge amount of powder in order to continuously knead the powder at a constant rate in a liquid which is continuously supplied.

[0002]

2. Description of the Related Art Generally, in backfilling work at a construction site, a large amount of a kneading liquid of a large amount of liquid and powder is often used at once. For example, at a tunnel construction site, water, bentonite and cement are kneaded. It is used to fill the underground frame with a liquid to improve the rigidity strength of the frame.

In such a case, it is particularly required to continuously supply a large amount of kneading liquid (commonly referred to as sludge liquid). Conventionally, in order to meet the above demand, quantitative liquid and powder have been supplied. A batch-type kneading method in which and are kneaded at once for a certain period of time is widely used. With the batch type kneading method,
A certain amount of liquid and a certain amount of powder are quantitatively charged into the kneader in a predetermined amount, and after kneading for a certain time, the kneading liquid is discharged to the intended purpose and the same cycle is repeated again. Was done to do.

[0004]

However, in order to obtain a large amount of kneading liquid at one time by the batch method, the amount of liquid and powder to be quantitatively added is increased and the kneading volume is increased accordingly. Inevitably, since it is designed to increase the number of kneaders, a large kneader (mixer) is used, or a plurality of kneaders are arranged in parallel to increase the cycle speed of the batch system. There was a problem of increasing the scale of the kneading device.

Further, since the liquid and powder to be charged into the kneading machine are quantitatively charged at one time, the kneading time (cycle time) becomes long and the kneading amount per unit time is small, so that the efficiency is improved. On the other hand, if the kneading time is shortened to give priority to efficiency, the kneading state of liquid and powder becomes insufficient and the composition ratio becomes unstable (uneven), resulting in uniform strength after curing in the application. There is also a problem that there is a risk of lack of a mixture, and a method for continuously kneading a kneading liquid of a liquid and a powder, which reliably holds a stable target kneading ratio, has not been developed.

The present invention is proposed in view of the above problems, and an object thereof is to continuously knead a liquid and a powder at a blending ratio that can reliably maintain a preset target kneading ratio. It is to provide a kneading type powder discharge amount control method.

[0007]

In order to achieve the above object, the present invention continuously supplies a liquid to a kneading machine while monitoring the flow rate thereof, and at the same time, supplies powder from a powder container to the kneading machine at a target kneading ratio. A first step of supplying a discharge amount commensurate with the above, and a step of calculating the actual discharge amount of the powder from this decrease amount by monitoring the decrease amount of the powder contained in the powder container with time. The second step, a third step of comparing a reduction amount of the powder with a target discharge amount for obtaining a target kneading ratio from the instantaneous flow rate of the liquid, and the powder when the actual discharge amount is different from the target discharge amount And a fourth step of correcting the discharge amount of the body so that the discharge amount matches the target kneading ratio.

[0008]

According to the above construction, first, in the first step, the flow rate of the liquid continuously supplied to the kneading machine is monitored, and based on the result of this monitoring, the powder corresponding to the predetermined target kneading ratio is discharged from the powder container. Supply to the kneader. Next, in the second step, the reduction amount of the powder in the powder container, which has decreased due to the supply to the kneading machine in the first step, is monitored, and the actual discharge amount of the powder is calculated from this reduction amount.

Further, in the third step, the target discharge rate for obtaining the target kneading ratio from the liquid flow rate monitored in the first step is compared with the discharge rate calculated from the powder reduction rate monitored in the second step. To do. When the actual discharge amount of the powder is different from the target discharge amount, that is, when the actual kneading ratio and the target kneading ratio do not match, the first kneading ratio is set so that the mixing ratio of the kneading ratio matches the target kneading ratio. The discharge amount of powder in the process is corrected.

As a result, it is possible to continuously supply, to the kneading machine, the powder having a blending ratio that always matches the target kneading ratio with respect to the liquid continuously supplied to the kneading machine. .

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An apparatus for carrying out the continuous kneading type powder discharge amount control method of the present invention will be described based on the embodiments of the drawings. FIG. 1 is a schematic view showing an example of a kneading-type powder supply device for carrying out the above-mentioned continuous kneading-type powder discharging method. In FIG.
The device A and the second device B of the second stage are provided side by side in series.

The first apparatus A of the first stage is roughly classified into a flow meter A1 for monitoring the instantaneous flow rate of water, a powder container A2 containing powdered bentonite, and a powder of the container A2. Powder feeder A3 for feeding the body to the kneader (continuous mixer) A9
An electric motor A8 for driving the feeder A3, and the electric motor A8.
8, a motor control device A4 for controlling the number of revolutions of the powder supply device A3 to control the powder discharge amount of the powder feeder A3, and the powder container A2.
A sensor A7 such as a load cell that suspends and supports three points to measure the total weight thereof, a weight sensor converter A5 that converts only the powder weight from the total weight measured by the sensor A7 into an electrical signal, and the flow rate. It is composed of a meter A1 and an arithmetic and control unit A6 which inputs and calculates an electric signal from the weight sensor converter A5 and outputs a control signal to a motor control unit A4 based on the result.

The arithmetic and control unit A6 has a built-in microcomputer for outputting control signals based on the programs shown in FIGS. 2 and 3 which will be described later, and controls all the functions in the first apparatus A and the second apparatus B. And calculates the instantaneous flow rate of water in the flow meter A1 and the amount of powder reduction in the weight sensor converter A5 to obtain the actual kneading ratio of water and powder at that time. When the calculation result is different from the actual target kneading ratio,
A control correction signal is output from the arithmetic and control unit A6 to the electric motor control unit A4 so that the rotation speed of the electric motor A8 is changed and the discharge amount of the powder discharged from the powder feeder A3 is adjusted to a blending ratio commensurate with the target kneading ratio. The discharge amount of the powder continuously supplied to the kneading machine A9, that is, the continuous mixer 30 is controlled so as to be the discharge amount.

Incidentally, as the kneading machine A9 in this case, a vertical continuous mixer 30 as shown in FIG. 4 is used as an example. The continuous mixer 30 includes a drive shaft 33 that rotates from an electric motor 31 communicating with a power source (not shown) via a transmission mechanism 32.
A rotatably supporting drive unit 34, a mortar-shaped casing 36 fixedly provided on the upper surface of the drive unit 34 and having an outlet 35, and the drive shaft 33 located above the casing 36. A rotating body 39 which is integrally supported with the shaft 33 at the upper end of and has a diffusion blade 37 and a powder rotating plate 38 integrally provided therein.
And a hopper-like lid 40 for covering the upper end opening surface of the casing 36, the upper end opening surface of the lid member 40 is closed, and a water supply port 41 is provided in the central portion and powder is provided in the peripheral region. The water supply port 4 is constituted by a lid plate 43 having an opening of the supply port 42, and when the power is turned on, the rotating body 39 is rotated via the drive unit 34.
The water supplied from No. 1 and the powder supplied from the powder supply port 42 are rotationally kneaded, and the kneaded liquid is discharged from the discharge port 35.

Next, the structure of the second device B will be described. The second device B is a flow meter B1 for monitoring the instantaneous flow rate of the mixed liquid continuously supplied to the kneading machine B9, a powder container B2 containing cement as powder, and the container. Powder feeder B3 for feeding the powder of B2 to the kneader B9
And an electric motor B8 in the feeder B3, and an electric motor B8
A motor control device B4 for controlling the number of revolutions of the powder feeder B3 to control the amount of powder discharged from the powder feeder B3, and a load cell for supporting the powder container B2 by three-point suspension and measuring the total weight thereof. A sensor B7, a weight sensor converter B5 that converts only the powder weight from the weight measured by the sensor B7 into an electric signal, the flow meter B1, and the weight sensor converter B5.
The electric signal from the motor control device B4.
It is composed of a first device A that outputs a control signal to a common arithmetic and control unit A6.

In the second device B as well as the first device A, the arithmetic and control unit A6 displays the instantaneous flow rate of the kneading liquid in the flow meter B1 and the reduction amount of the powder, that is, the cement in the weight sensor converter B5. The actual kneading ratio of the kneading liquid and the powder is calculated to calculate, and when the calculated actual kneading ratio is different from the target kneading ratio, a control correction signal is sent from the arithmetic and control unit A6 to the electric motor control unit B4. The kneading machine B9, that is, the continuous mixer B30, is configured such that the output amount of the powder discharged from the powder feeder B3 is varied by changing the rotation speed of the electric motor B8 so that the discharge amount is a blending ratio corresponding to the target kneading ratio. The powder is continuously supplied to.

Incidentally, the continuous mixer B3 used in this case.
0 indicates a powder (cement) receptacle B31 as shown in FIG.
And the discharge port B32 of the mixed liquid is provided below the receiving port B31 to form a chute body B33 having a slope through which the mixed liquid can flow.
A powder (cement) discharged from the powder feeder B3 to the receiving port B31 is provided with a nozzle B34 for spraying a liquid in the upper end that is substantially equal to the receiving port B31.
In the submersible pump B, the kneading liquid of bentonite and water kneaded in the first device A and stored in the relay tank B11 is
The powder (cement) is sprayed in the form of a spray through the pressure nozzle B34 of 10, and the powder (cement) is diffused in the chute body B33 and mixed uniformly with the kneading liquid to produce a mixed liquid of bentonite, water and cement. Then, it is configured to be supplied from the discharge port B32 for backfilling work and the like.

Next, the operation of the embodiment configured as described above will be described with reference to the flow charts shown in FIGS. This example is mainly for backfilling work at a construction site, and a mixing ratio that achieves a predetermined target kneading ratio of powder to be supplied to a mixed liquid of cement mixed with a kneading liquid of bentonite and water as the backfilling material. It is used to consistently produce the mixed solution by continuously feeding it.

The mixing ratio for attaining the target kneading ratio of the powder is calculated by calculating the electric signal input to the arithmetic and control unit A6 according to the formula shown in Formula 1 and calculating the powder supply unit A3, or This is performed by controlling the discharge amount of B3.

[0020]

[Equation 1]

The operation of the arithmetic and control unit A6 is performed based on the program shown in the flow charts of FIGS. The device of the first device A is controlled by the program of FIG. First, when the power is turned on by the start, all the functions are ready to operate. Then, in (S1), the instantaneous flow rate of water is measured by the flow meter A1, and the measured value is input to the arithmetic control device A6 to
The required discharge amount of the powder corresponding to the flow rate of the water is calculated at 6 (S2), and the control amount of the powder feeder A3 is roughly set based on the calculated discharge amount, and the control signal is sent to the motor control device A4.
(S3). Thereby, the rotation speed of the electric motor A8 is controlled, and the discharge amount of the powder discharged from the powder feeder A3 to the kneader A9 is set and supplied (S4). ...... (First step) After that, the weight of the powder container A2 reduced by the supply is measured by the sensor A7 such as a load cell, and the time-dependent reduction amount is output to the arithmetic and control unit A6 via the weight sensor converter A5. Then
The actual discharge amount of the powder is calculated from this decrease amount, and (second step) whether this discharge amount matches the preset target discharge amount for obtaining the target kneading ratio of water and powder. Are compared (S5). ... (Third step) If the actual discharge amount of the powder and the target discharge amount in (S5) do not match, that is, if the kneading ratio of water and powder does not match the target kneading ratio, (S8) ), A correction control signal is output from the arithmetic and control unit A6 to the electric motor control unit A4 to change the rotation speed of the electric motor A8 (S8), and the discharge amount of the powder discharged from the powder feeder A3 to the kneader A9 is changed to The ejection amount is corrected and supplied at a rate that matches the target kneading ratio.
(Step 4) If the comparison results in (S5) above match,
Alternatively, because of a mismatch, after correcting and matching in (S8), the liquid flow rate is monitored (S6), the required discharge amount of the powder commensurate with that is calculated over time, and the process returns to (S4) again to perform the above operation. While repeating the above, the powder is supplied from the powder feeder A3 to the kneader A9 in a proportion that matches the target kneading ratio.

The device of the second device B is controlled by the program shown in FIG. First, the power is turned on by the start, and all the functions can be operated. And flow meter B
1, the instantaneous flow rate of the kneading liquid kneaded by the first device A is measured (S9), and the measured value is calculated by the arithmetic and control unit A6.
The calculation is performed by adding a correction coefficient according to the equation (2), and the discharge amount of the submersible pump B10 is controlled based on the calculation result to adjust the flow rate of the kneading liquid.

[0023]

[Equation 2]

Then, the required discharge amount of powder corresponding to the adjusted flow rate of the kneading liquid is calculated (S11), and based on this, the powder discharge control amount of the powder feeder B3 is roughly set and the control is performed. The signal is output to the motor control device B4 (S
12). Thereby, the rotation speed of the electric motor B8 is controlled, and the discharge amount of the powder discharged from the powder feeder B3 to the kneading machine B9 is set and supplied (S13). ...... (First step) After that, the weight of the powder container B2 reduced by the above-mentioned supply is
It is measured by a sensor B7 such as a load cell and the amount of decrease over time is output to the arithmetic and control unit A6 via the weight sensor converter B5, and the actual discharge amount of powder is calculated from this amount of decrease, ...
(Second step) Whether or not this reduction amount matches a preset target discharge amount for obtaining a target kneading ratio between the kneading liquid and the powder is compared (S14). ... (Third step) If the actual discharge amount of the powder and the target discharge amount in (S14) do not match, that is, if the kneading ratio of the kneading liquid and the powder does not match the target kneading ratio, calculation is performed. Control device A6
A correction control signal is output from the electric motor control device B4 to change the rotation speed of the electric motor B8 (S18).
The discharge amount of the powder discharged from No. 3 to the kneading machine B9 is corrected and supplied to a discharge amount of a ratio matching the target kneading ratio. ...... (Fourth step) If the comparison results match in (S14) or if they do not match and are corrected and matched in (S18), the liquid flow rate is monitored (S15).
The required discharge amount of the powder corresponding to it is calculated with time, and the process returns to (S13) and the above-described operation is repeated to supply the powder from the powder feeder B3 to the kneader B9 in a proportion that matches the target kneading ratio. .

The cement as the powder supplied is supplied to the nozzle B34 in the continuous mixer B30 as the kneader B9.
The mixed liquid of bentonite and water cement, which has been diffused into the kneading liquid of water and uniformly mixed by being sprayed from, is mixed and discharged continuously from the discharge port B32. The level sensor B15 provided in the relay tank B11 is connected to the arithmetic and control unit A6 by an electric circuit, and is connected to the relay tank B11.
The liquid volume inside is monitored.

In the embodiment, the actual discharge amount of powder is controlled so as to match the target discharge amount for obtaining the target kneading ratio. However, the actual kneading ratio is calculated from the actual discharge amount, This may be controlled so as to match the target kneading ratio.

[0027]

As described above, the present invention does not quantitatively determine the mixing ratio of the liquid and the powder to be kneaded as in the conventional batch system, but monitors the flow rate of the liquid continuously supplied. Based on this, the required discharge amount of powder that matches the target kneading ratio is calculated and kneaded, so that the kneading time (cycle time) can be shortened and set without making the device large-scale unlike the batch type. Since a kneading liquid that reliably maintains the target kneading ratio can be obtained continuously, work efficiency can be improved, and when this kneading liquid is used as a backfill material at a construction site, for example, the rigidity strength after hardening of the kneading liquid can be improved. In addition, it has the effect of ensuring uniform stability.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart for controlling the first stage.

FIG. 3 is a flowchart for controlling the second stage.

FIG. 4 is a side sectional view of a continuous mixer.

FIG. 5 is a schematic side view of a continuous mixer.

[Explanation of symbols]

 A2 powder container B2 powder container A9 kneading machine B9 kneading machine

Claims (1)

[Claims] 1. A first step of continuously supplying a liquid to a kneading machine while monitoring a flow rate thereof, and supplying a powder from the powder container to the kneading machine at a discharge amount corresponding to a target kneading ratio, A second step of monitoring the decrease amount of the powder contained in the powder container over time and calculating the actual discharge amount of the powder from this decrease amount; the discharge amount of the powder and the liquid And the third step of comparing the target discharge amount to obtain the target kneading ratio from the instantaneous flow rate of, and the discharge amount of the powder commensurate with the target kneading ratio when the actual discharge amount is different from the target discharge amount. A continuous kneading-type powder discharge amount control method, comprising: