JPH021643B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous mixing device for powdered milk (slurry) in which cement milk or other powder similar to cement is mixed with a liquid.

Cement milk is a typical example of the powdered milk mentioned above, and although cement milk mixing equipment has already been developed and put into practical use, the conventional equipment is a batcher-type plant and is extremely large. However, the control and drive mechanism is not well maintained, requiring a great deal of effort for maintenance and management. Therefore, a compact mixing device has been developed that replaces the batcher type with a continuous mixer mechanism. Although miniaturization has advantages in terms of maintenance and management, it requires a complicated control drive device to improve the accuracy of slurry concentration. Therefore, a small-sized mixing device that ensures the accuracy of cement milk concentration and that can be operated continuously with high efficiency has not yet been developed.

The present invention relates to a continuous mixing device for powdered milk (slurry) such as cement, which was developed in view of the above-mentioned circumstances, and includes a slurry discharge pipe extending from a jet mixer to a slurry tank, and a mixing pump for discharging the slurry in the slurry tank. A mixing pump line that circulates to the nozzle part of the jet mixer, a device for quantitatively supplying powder to the jet mixer, a quantitatively supplying line for water that joins the mixing pump line to the suction side of the mixing pump, and a line that branches off from the additive tank. It has a line that is connected to the mixing pump line through the water supply line and a line that extends to the slurry tank, and a line that selectively supplies additives in fixed quantities through either of these lines, and a line that supplies the slurry from the slurry tank to the outside. a mixing device consisting of a line for sending out the
An automatic concentration setting device that circulates the slurry through the device until the mixing device reaches a set concentration, and then an automatic continuous mixing device that automatically and continuously mixes the mixing device intermittently according to slurry consumption in the slurry tank and changes in the slurry level in the slurry tank. It is characterized in that it is equipped with a control device for operating the powder, and furthermore, in the above structure, the powder constant supply device is formed integrally with a volumetric feeder section such as a table feeder on the same feeder section. The feeder and the hopper are supported via a weight measuring device such as a load cell, and a control device controls automatic concentration setting operation of the mixing device based on the measured value by the weight measuring device. The present invention is characterized in that it includes an automatic operation sequence that automatically checks the amount of powder supplied at regular intervals during automatic mixing operation.

In addition, the control device has an automatic operation sequence that supplies a specified amount of water to the slurry tank when the mixing device is started, then starts the mixing pump, supplies powder to the jet mixer, and enters automatic concentration setting operation. It is characterized by the fact that

Additionally, the control device supplies a specified amount of water to the slurry tank when the mixing device is started, then starts the mixing pump, supplies the powder to the jet mixer, and then passes the additive through a line extending above the slurry tank. It is characterized by having an automatic operation sequence in which additives are supplied into a slurry tank and operated to automatically set a temperature, and then when continuous mixing operation starts, the additives are switched to a line connected to a mixing pump line and supplied.

In addition, a pressure detector is installed at the back of the nozzle of the jet mixer during mixing operation, and the control device automatically stops the continuous mixing operation of the mixing device based on abnormality detected in the nozzle back pressure of the mixer by the pressure detector. It is characterized by having a driving sequence.

In addition, a pressure detector is provided in the hopper section of the jet mixer of the mixing device, and the control device sets an operation sequence that automatically stops the continuous mixing operation of the mixing device based on abnormality detection of negative pressure in the hopper by the pressure detector. Their purpose is to use a jet mixer to create a small continuous mixing device, and to ensure concentration accuracy and to be equipped with a control device that enables fully automatic continuous operation. The present invention provides a continuous mixing device for powdered milk such as cement.

The present invention has the above-mentioned configuration, and includes a jet mixer, a slurry discharge pipe extending from the jet mixer to a slurry tank, a slurry tank, and a mixing pump line that circulates slurry from the slurry tank to the nozzle side of the jet mixer using a mixing pump. Because it has a circulation and mixing configuration, the mixing function can be significantly downsized, and the strong mixing action and circulation have the advantage that the concentration of slurry in the device is always uniform. It is a high-performance product that can continuously obtain a large amount of slurry with high concentration accuracy by being equipped with a device for continuously supplying appropriate amounts of mixing water and additives.

Furthermore, in the present invention, all of the above-mentioned mechanisms are fully automatic and can be controlled and driven by a control device, and the control includes automatic concentration setting operation until the slurry reaches an appropriate concentration at startup, and thereafter. The system continuously supplies powder, mixed water, and additives in the appropriate amount and ratio in accordance with the consumption amount delivered from the slurry tank, and circulates and mixes them to constantly maintain a fixed amount of the appropriate concentration in the slurry tank. Since continuous mixing operation is possible in which slurry is replenished and secured, an appropriate amount of slurry with an appropriate concentration is always secured from the beginning of operation through continuous mixing operation, and the slurry mixing ability is greatly improved. In addition, in the present invention, as mentioned above, the slurry concentration accuracy and mixing efficiency are significantly improved, and the device itself is smaller than conventional devices, which greatly reduces operational management effort and maintenance. This makes it easier and equipment costs are also significantly lower in terms of mixing efficiency. Furthermore, the effects described below (from the end of page 23) can be obtained.

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

FIG. 1 is an overall mechanical diagram showing an embodiment of the mixing apparatus of the present invention, in which 1 is a jet mixer, a slurry discharge pipe a extending from the jet mixer 1 to a slurry tank 3, and a A mixing pump line b that circulates the slurry to the nozzle part of the jet mixer 1 by the mixing pump 4, a device for quantitatively supplying powder (cement) to the jet mixer 1 (details will be described later), and a suction of the mixing pump 4 in the mixing pump line b. It has a fixed quantity supply line c of water joined to the side, a line d branched from the additive tank g and extended onto the slurry tank 3, and a line e connected to the mixing pump line b via the water supply line c. death,
The mixing device has a structure consisting of lines d and e that selectively supply a fixed amount of additive through either of the lines (d or e), and a line f that sends the slurry from the slurry tank 3 to the outside. Furthermore, this mixing device is equipped with a control device that performs an automatic concentration setting operation, which will be described later, and an automatic continuous mixing operation intermittently.

To explain the mixing device and control device in more detail, in FIG. 1, 1 is a jet mixer, 2 is a jet mixer hopper, 3 is a slurry tank, 4 is a mixing pump, 5 is a strainer,
6 is an agitator, 7 is a table feeder that supplies powder such as cement to the jet mixer 1, 8 is a table feeder hopper on the table feeder, 9
10 is a mixing water pump that transfers water from the mixing water tank h; 10 is an additive pump that supplies additives; 11
12 is a powder charge hopper; 13 is a rotary feeder that supplies powder to the table feeder hopper 8;
15 is a pump and addition circuit for the load cell 14, and 16 is an instrument for displaying and recording the weighing results, which is similar to the above-mentioned jet mixer hopper. 2. The table feeder 7, the table feeder hopper 8, and their attached mechanisms (load cell 14, etc.) constitute a powder quantitative supply device.

In addition, 17 is a bucket conveyor that supplies powder to the charge hopper 12, 19 is a screw feeder, 20 is a rotary feeder, 21 is a gate valve, 22 is a cement silo, and 23 is a level meter attached to the hopper 12. When the level is detected, the rotary feeder 20 at the bottom of the cement silo 22 is started, and when the high level is detected, the rotary feeder is stopped.

Furthermore, the table feeder 7 has a tachometer 24.
is attached to detect the rotation speed of the powder supply vane (not shown) inside the table feeder 7. Reference numeral 25 indicates an electric motor for the table feeder, 26 indicates a variable speed reducer, a pressure gauge 27 is attached to the jet mixer hopper 2 for detecting the pressure inside the hopper, and a pressure gauge 27 for detecting the pressure inside the slurry pipe is installed immediately before the jet mixer 1. Another pressure gauge 28 is attached to measure the pressure.

29 is a remote control valve for supplying mixed water, 30 is an electromagnetic flowmeter for measuring the flow rate of mixed water, 31 is a control valve for adjusting the flow rate of mixed water, and 32 is for supplying additives. 33 is a flow meter for additives, 34 is a flow control valve for additives, and 35 is a remote control valve for directly supplying additives to the slurry tank.

36 is a bypass valve used to set the mixing water amount, and 37 is a bypass valve for setting the additive flow rate.

38 is a level meter for detecting that the liquid level in the slurry tank 3 is high, 39 is a level meter for detecting that the liquid level is low, and 40 is a level meter for indicating that the liquid level is too low. 41 indicates a control device that controls the entire plant.

Since the illustrated embodiment of the mixing device has the above-described structure, at the beginning of operation, the remaining slurry in the slurry tank 3 is transferred to the mixing pump 4.
The slurry is then circulated through the mixing pump line b to the nozzle side of the jet mixer 1 and jetted into the jet mixer 1, and an appropriate amount of powder (cement) supplied from the table feeder 7 and the jet mixer hopper 2 is added to the spouted slurry. After being instantaneously mixed with the water, the slurry is discharged into the slurry tank 3 again through the slurry discharge pipe a, and the mixed water supplied from the water constant supply line c is mixed with the slurry tank 3.
An appropriate amount of the additive supplied from line d extending to The stored slurry having the proper concentration is transferred from the delivery line f by the injection pump 11 or the like to a processing machine (not shown) for ground improvement, for example, and is consumed. Powder, water, and additives are continuously replenished in the appropriate amount and proportion in accordance with the amount consumed, and through the above-mentioned circulation and mixing, the appropriate concentration and amount corresponding to the consumption amount is continuously supplied. It is a continuous mixing operation in which slurry is replenished, and the control drive described above is performed by the control device described later, so the device can be made smaller, and the slurry concentration is increased by the powerful mixing action of the jet mixer and the circulation of the slurry within the device. is equalized,
Furthermore, through the concentration setting operation at the beginning of operation and the continuous mixing operation, an appropriate amount of slurry with high concentration accuracy is always ensured, and fully automatic control achieves high efficiency, and the equipment is easy to maintain and manage.

In the above embodiment, it is also possible to omit the charge hopper 12 and directly feed powder (cement) etc. to the table feeder hopper 7, and in the above embodiment, the slurry may be fed to a processing machine for ground improvement. Although the explanation is given by way of example of supplying milk, the present invention is not limited to this example and can also be used for sending and consuming other types of milk-requiring equipment.

Next, to explain in detail the control device that controls and operates the mixing device, FIGS. 2 and 3 are control flow diagrams of the device that controls the operation of the mixing device, that is, the plant control device 41 shown in FIG. 1. The operation of the apparatus by the illustrated control device can be roughly divided into two stages: a concentration setting stage at the time of starting the apparatus, and a continuous mixing stage after the concentration setting stage. FIGS. 2 and 3 specifically describe the control flow described above, and the concentration setting stage is
．． When the density setting button is pressed. A specified amount of water is supplied to the slurry tank 3, and then... After starting the mixing pump 4, the table feeder 7
, and mix the powder by supplying the amount of powder corresponding to the previously supplied water. next. If mixing of additives is required, add the additives using the additive direct injection valve 35.
By opening the slurry tank 3, a specified amount is poured into the slurry tank 3. The reason why the additive is added after the powder is added is that when using an additive that has an air entrainment effect, the mixing pump is operated with only water, and the mixing pump is operated with air entrained by the mixing of the additive. This is to prevent interference.

When the operation up to this point is completed, slurry of a specified concentration is created in the slurry tank 3.

here,. A load cell 14 detects whether the discharge speed of the table feeder 7 has reached a specified value and detects changes in the powder weight in the table feeder hopper 8.
Sample for a certain period of time and print out the weight loss value on a printer to check. ．．
If the amount does not reach the specified value, adjust by changing the reduction ratio of the variable speed reducer 26 or by changing the rotation speed of the electric motor 25.

This completes the concentration setting stage, and the next continuous mixing operation stage begins, in which the slurry in the device continues to circulate until the continuous mixing push button is pressed. ．． When the continuous mixing push button is pressed. powder (cement),
Supply of water and additives begins, and mixing operation begins. At this time, the rotary feeder 13 of the charge hopper 12 is not operated for a certain period of time, and the weight loss rate of the table feeder hopper 8 is controlled by the load cell 1.
4 to check the feeding accuracy of the table feeder. Print out.

next,. Enter normal continuous mixing operation. Here, the level of slurry tank 3 is constantly monitored.
If a high level 38 is detected, the supply of powder, water, and additives will be stopped. Pause. When the slurry is transferred by the injection pump 11 and detected by the lower level meter 39 of the slurry tank 3, . Supply resumed again. Mixed operation continues.

here. When the continuous mixing pause button is pressed. The supply of water, additives and powder (cement) is stopped. and,. The integrated values of the supply amounts of water, additives, and powder (table feeder rotation speed) are printed out.

．． Press the continuous mixing stop button. Not only the water, additive, and powder supplies are stopped, but also the mixing pump 4, agitator 6, and the mixer itself is stopped. Also in this case. The cumulative amount will be printed out.

4 to 18 show an embodiment of more detailed sequence control flow diagrams for realizing the above-mentioned control flow, and the symbols in these diagrams are as explained in FIG. 19.

In Figure 4, the print control is set to automatic and the density setting operation push button is pressed.
When turned ON, concentration setting operation stage 1 starts. This state is held by the flip-flop F1 and is reset when the continuous operation ends. After a certain period of time after the concentration setting operation stage 1 is activated, the concentration setting operation stage 2 starts via the delay DL1. In this state, when the integrated value of the mixed water totalizer reaches a predetermined value, the ANDA2 condition is satisfied and the sequence moves to concentration setting operation stage 3. After a certain period of time has elapsed due to delay DL2, concentration setting operation stage 4 is reached.

In this state, the ANDA3 concentration setting operation stage 5 is reached on the condition that a specified amount of powder (cement) weight has been discharged. Then, when the additive supply amount reaches the specified amount, the concentration setting operation is ended by ANDA4.

At each stage, the sequence controller controls the equipment in the system as shown in FIGS. 8 through 17.

In FIG. 5, when the automatic selection is completed, the concentration setting operation is completed, and the concentration mixing operation push button is pressed, the condition ANDA5 is satisfied. Here, the level of table feeder hopper 7 (load cell 1
If the level (measured by level 4) is above a certain level, the condition of ANDA6 is satisfied, and mixing operation stage 1 is set. Flip-flop F2 is reset at the end of continuous operation. If the level of the table feeder hopper 8 is low, an indication that the level of the table feeder hopper is insufficient is displayed and the system waits for the level to recover.
After the mixing operation stage 1 is set and a certain period of time has elapsed, the delay DL3 enters the mixing operation stage 2. Here, when the mixed water flow meter 30 detects that the mixed water is flowing, the mixing operation stage 3
to go into. There, powder supply was started and a delay
The supply amount of the table feeder 7 is checked for a certain period of time by DL4, and the mixing operation stage 4 is entered.
This stage represents a normal continuous mixing operation stage.

FIG. 6 shows a flip-flop F3 for inhibiting the operation of the charge hopper rotary feeder 13 during the table feeder check period from stage 1 to stage 4. Set at stage 1, reset at stage 4.

In FIG. 7, when the pause push button for continuous mixing operation is pressed or when a mixer abnormality is detected, the mixing operation stage 5 is reached via OR circuit R1. Daylay DL5 mixed operation stage 6 after a certain period of time
reach. When the continuous mixing operation stop button is pressed or when the lowest slurry tank level is detected, up to stage 6 it is the same as a temporary stop, but the flip-flop F4 is set and the condition A9 is met and the continuous operation ends.

This flip-flop F4 is set by activation of the concentration setting operation stage 1.

In FIG. 8, the conditions for starting the mixing pump 9 to high speed operation are the concentration setting operation stage 3.
This is when the continuous mixing operation stage 7 is reached. This operating state is maintained at F5. When the concentration setting operation ends or continuous operation stage 6 is reached, F
5 is reset, and the high-speed operation of the mixing pump 4 ends. Also, if manual is selected here, the pump can be operated manually.

The pump can also be stopped by pressing the emergency stop push button E. The mixing pump is operated at low speed until F5 is reset and continuous operation ends. The agitator 6 in the slurry tank 3 operates from the start of the concentration setting operation stage 3 until the end of continuous operation.

In FIG. 9, the additive pump 10 operates when the concentration setting operation stage 1 is turned on. The same applies to the mixed water pump 9. The mixing water valve 29 is activated when the concentration setting operation stage 2 is ON (that is, the stage that supplies a specified amount of water to the slurry tank 3), or when the mixing operation stage 2 is ON and the level wait of the slurry tank 3 is ON. A21 opens at .

Flip-flop F that maintains the state of the mixing water valve
8 resets and closes the additive valve 32 when the mixing operation stage 5 or the slurry tank level signal turns OFF. Additive valve 32 opens when flip-flop F8 is set and closes when reset.

In FIG. 10, the conditions for table feeder 7 to operate are that concentration setting operation stage 1 is ON, concentration setting operation stage 4 or mixing operation stage 3, and the slurry tank level signal is ON.
When it is ON, flip-flop F9 is set and table feeder 7 is operated.

When the slurry tank level signal is OFF or the mixing operation stage 5 or the concentration setting operation stage 5 is reached, the flip-flop F9 is reset and the table feeder 7 is stopped. The table feeder 7 can also be operated manually.

In FIG. 11, conditions for opening the additive direct injection valve 35 are shown. In concentration setting operation stage 5, flip-flop F10 is set, and when the preset value at which valve 35 is opened is reached, F10 is reset and valve 35 is closed.

In FIG. 12, operating conditions of the charge hopper rotary feeder 13 are shown. When the concentration setting operation stage 1 is ON and the continuous mixing operation feeder check time is ON, even if the table feeder hopper 8 is at a low level, the flip-flop F
11 is not set and the rotary feeder does not operate.

In other conditions, table feeder hopper 8
When the level becomes low, the table feeder operates, and when the level becomes high, it stops, thereby maintaining the level in the table feeder hopper 8 within a constant range.

Fig. 13 shows the abnormality detection sequence, and Fig. 14 shows the abnormality detection sequence.
The figure shows the output of the automatic/manual switching signal, and Figure 15 shows the output conditions of the slurry tank level signal.
Further, FIG. 16 shows the operation sequence of the rotary feeder 20 of the cement silo, which can be understood from the illustrated content.

FIG. 17 shows the sequence of measuring and recording powder, water, and additives. The signal from the load cell 14 of the table feeder hopper 8 is amplified by adding the signals from the three load cells, and the signal is analog / converted to digital. Digital signals are input to the printer in the form of binary signals.

The pulse signal from the table feeder rotation detector 24 enters the totalizer. The output from the totalizer (No. 1) enters the printer in binary code.

The signal of the mixed water flow meter 30 is converted into a pulse signal by the analog-to-digital converter AD2, and the signal is converted to a pulse signal by the totalizer (No.
2). The output from the totalizer is converted into a binary code and input to the printer.

The pulse signal from the additive flow meter 33 is input to the totalizer (No. 3), and the total value is input to the printer in the form of a binary coat.

The timing at which the printer is triggered to print out is, in the case of trigger 1, when the load cell 14 of the table feeder hopper 8 shows the specified value, and at the mixing operation stages 2 and 4 and the concentration setting operation stage 4. Go out. This printout is used to check the table feeder 7. For trigger 1, input 1 and input 2 are printed out. The No. 1 totalizer is reset when the printout is completed in the density setting operation stage 4 (all reset inputs are assumed to have built-in delays - not shown).

The print trigger 2 is output when the concentration setting operation is completed, at the mixing operation stage 6, or at the time of emergency stop. At this time, input 2, input 3, and input 4 are printed out.

The No. 2 and No. 3 totalizers are reset at the concentration setting operation stage 1 or the mixing operation stage 2.

The structure and operation of the illustrated embodiment have been explained in the above description, but the effects of the present invention will be further explained as follows: (a) Regarding the feeding speed check system for the table feeder 7, the table feeder 7 Because it is a weighing method, it is common for errors to occur due to fluctuations in the apparent specific gravity of the powder compared to gravimetric methods. Therefore, if high accuracy is to be obtained using the capacitance metering method, it is necessary to carry out calibration by gravimetric metering. This system incorporates the calibration system into an automatic sequence, and for this purpose, a feeder such as a table feeder and a hopper are integrated, and the entire system is supported by a weight measuring device such as a load cell. ing.

To check the table feeder feeding speed,
This is done by monitoring the reduction value of the amount of powder in the hopper for a certain period of time, or by checking the relationship between the rotation speed of the table feeder and the powder flow rate value.

This check is automatically performed within a certain period of time after the start of operation each time the mixer is started.
After this calibration is performed, only the number of rotations of the table feeder is accumulated and recorded, and by combining this with the calibration results, the amount of feed can be determined.

It is also possible to perform a sampling check during operation at arbitrary time intervals other than the fixed time at the start of operation by appropriately combining it with a timer.

In this example, the cumulative amount of powder supplied is recorded as the cumulative value of the table feeder rotation speed, but by combining appropriate calculation logic, it can be corrected using the value obtained from the table feeder check. It is also possible to add it automatically and record it as the amount of powder supplied. These are powdered milk (slurry)
This will greatly improve the mixing accuracy.

(b) Regarding the mixer startup sequence, when starting the mixer, pour the specified amount of water into the slurry tank,
Next, we use an automatic sequence system that starts the mixing pump and adds a specified amount of powder, which improves the mixing efficiency at startup.

(c) Regarding the additive injection sequence, during the concentration setting operation when starting the mixer, the additive is added after the powder is added to prevent air intrusion, and when normal mixing operation starts, the additive is injected into the mixed water. This makes it possible to eliminate powder mixing defects caused by air inclusion at the start of the process.

(d) Regarding mixer abnormality detection and abnormality sequence, (a) Mixer nozzle pressure detection (Fig. 13,
(Fig. 8), the pressure inside the slurry pipe must be within a certain pressure fluctuation range; if it exceeds the upper limit, it indicates that the nozzle in the mixer is blocked by foreign matter, and if it falls below the lower limit, the mixing pump Indicates that an abnormality has occurred. In both cases, a signal is output in sequence by a meter relay (not shown) built into the pressure detector 28.
If this abnormality occurs, immediately stop the supply of powder and water.

(b) Mixer hopper negative pressure detection (Fig. 13, 1
(Fig. 8), when the jet mixer is working normally, there is a constant negative pressure inside the jet mixer hopper. When this is detected, an abnormal signal is output and the supply of powder and water is immediately stopped.

(c) Slurry tank level detection (Figure 13),
If the slurry level in the slurry tank 3 rises or falls to a certain extent, the mixer cannot operate normally. This is detected and the supply of powder and water is stopped.
Stop the mixing pump.

(d) Table feeder hopper level detection (first
(Figure 3), if a problem occurs in the powder supply line and the amount of powder in the table feeder hopper falls below the limit, powder will not be properly supplied to the mixer. It detects that the level has fallen below the limit and stops the supply of powder and water.

By early detection of these abnormalities, it is possible to prevent the expansion of equipment failures, reduce downtime, and increase operational efficiency.

According to the above-mentioned control device, in addition to improving slurry concentration accuracy through concentration setting operation at the beginning of operation, i.e., startup, subsequent continuous mixing operation, and greatly increasing mixing efficiency through fully automatic control, It also enables various responses.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design changes can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

Fig. 1 is an overall mechanism diagram of an embodiment of the present invention, Fig. 2 is a control flow diagram showing an outline of the operating sequence of the embodiment, and Figs. 3 to 18 show detailed operating sequences of the embodiment. The logic diagram, FIG. 19, is a symbolic explanatory diagram of the same sequence logic. 1: Jet mixer, 2: Jet mixer hopper, 3: Slurry tank, 4: Mixing pump, 7: Table feeder, 8: Table feeder hopper, 9: Mixing water pump, 10: Additive pump, 11: Infusion pump, 14: Load cell, 1
5: Addition circuit, 16: Instrument, a: Slurry discharge pipe, b: Mixing pump line, c: Water constant supply line, d: Additive line, e: Other additive line, f: Sending line, g: additive tank, h: mixing water tank.

Claims (1)

[Scope of Claims] 1. A slurry discharge pipe extending from the jet mixer to the slurry tank, a mixing pump line for circulating the slurry in the slurry tank to the nozzle part of the jet mixer by a mixing pump, and a device for quantitatively supplying powder to the jet mixer; A quantitative supply line of water joined to the suction side of the mixing pump of the mixing pump line, a line branched from the additive tank and extended to the slurry tank, and a line connected to the mixing pump line via the water supply line. a mixing device consisting of a line for selectively supplying a fixed amount of additive through any of the lines, and a line for sending slurry from a slurry tank to the outside; and a control device that causes the mixing device to perform an automatic continuous mixing operation intermittently according to slurry consumption in the slurry tank and changes in the slurry level in the slurry tank. A continuous mixing device for powdered milk such as cement. 2. The powder quantitative supply device includes a volumetric feeder section such as a table feeder and a hopper section integrally formed on the feeder section, and the feeder and hopper section include a weight measuring device such as a load cell. supported through
and includes an automatic operation sequence in which the control device automatically checks the amount of powder supplied at regular intervals during automatic concentration setting operation and automatic continuous mixing operation of the mixing device based on the measured value by the weighing device. The continuous mixing device for powdered milk according to claim 1, characterized in that: 3 The control device has an automatic operation sequence that supplies a specified amount of water to the slurry tank when the mixing device is started, then starts the mixing pump, supplies powder to the jet mixer, and enters automatic concentration setting operation. Claim 1 characterized in that
Continuous mixing device for powdered milk as described. 4 The control device supplies a specified amount of water to the slurry tank when the mixing device is started, then starts the mixing pump, supplies the powder to the jet mixer, and then passes the additive into the slurry tank through a line extending above the slurry tank. Claim 1 characterized by comprising an automatic operation sequence in which the additive is supplied to the mixing pump line for automatic concentration setting operation, and then when continuous mixing operation starts, the additive is switched to a line connected to the mixing pump line and supplied. Continuous mixing equipment for powdered milk. 5. A pressure detector is provided at the back of the nozzle of the jet mixer of the mixing device, and the control device has an automatic operation sequence that automatically stops the continuous mixing operation of the mixing device based on abnormality detected in the nozzle back pressure of the mixer by the pressure detector. The continuous mixing device for powdered milk according to claim 1, characterized in that: 6. A pressure detector is provided in the hopper section of the jet mixer of the mixing device, and the control device is equipped with a motion sequence that automatically stops the continuous mixing operation of the mixing device based on abnormality detection of negative pressure in the hopper by the pressure detector. The continuous mixing device for powdered milk according to claim 1, characterized in that: