JPH01100613A - Liquid measuring, mixing and distributing device - Google Patents

Abstract

PURPOSE:To improve measuring accuracy of the titled device and to simplify its facilities by performing a fuzzy control with the measurement controller of a closed loop, which makes a flow velocity variable, moving a mixing container provided with a measuring device, and performing measurement. CONSTITUTION:Using a measurement controller 6 of the closed loop control to make the flow velocity variable, and by the control system of a fuzzy inference, the valve opening of an opening regulating valve 2 for plural supplying containers and for a distributing container is made variable by a switching device 7, which is a part of a device constitution. Further, a mixing container 4 is conveyed by a moving device, a measuring device 5 set on the side of the mixing container 4 measures liquid from the plural supplying containers and the mixed liquid from the mixing container 4 to the distributing container, for the plural supplying containers, which can be accumulatively measured, the measurement is attained using a linking pipe, and by a measurement controller 6 having one mixing container 4 and one measuring device 5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a liquid metering method that measures and mixes various raw material liquids to prepare a new mixed liquid, and then dispenses the mixed liquid into a dispensing container. The present invention relates to a mixing and dispensing device, and particularly to a liquid metering, mixing and dispensing device that precisely and efficiently measures, mixes and dispenses raw material liquids over a wide measuring range.

[Conventional technology]

Conventionally, in order to achieve high-accuracy metering, there has been no metering device applied to liquid metering, mixing, and dispensing devices that has a variable supply liquid flow rate, but a metering device that limits the flow rate to a flow rate corresponding to the metering setting value. It was used.

In addition, in a conventional type of liquid metering mixing and dispensing device, liquid is supplied from a plurality of supply containers to one mixing container,
When dispensing the mixed liquid into dispensing containers, each supply and dispensing container is provided with a metering device.

For example, when a volumetric type liquid metering mixing and dispensing device is used, two measuring devices are used for the two supply containers for liquids A and B, as shown in Figure 5, and two measuring devices are used for the two supply containers for liquids A and B. This patent features a two-loop control function as a control device for predictive control of the inflow amount.In other words, the flow rate of the supplied liquid is controlled by the amount of liquid in the supply container of liquids A and B, valve flow characteristics, liquid physical properties, etc. This is because highly accurate measurement cannot be expected with the same control function.

Similarly, when dispensing into distribution containers C and D, two metering devices are used. Therefore, in this case, a total of four weighing devices will be used.

This also applies to the tank metering system, and the shutoff valves of the actuators attached to each system must be controlled by independent loop control systems (Japanese Patent Laid-Open No. 57-2
No. 9114, JP-A-58-163426, JP-A-56
-74715, see each publication).

In addition, in order to achieve highly accurate metering, there is a method of installing valves with different flow rates in parallel and switching at a predetermined metering deviation, but even in this case, 4-loop control is required as a control function. .

Here, the expression 4-loop control function is used because, for example, when a distributed control device is used, processing can be performed within one control device, and four control devices are required. This is because it cannot be said. However, in terms of the number of input/output points and software, it can be said that there are four control devices.

By the way, as a dispensing device, it is often the case that the level of measurement accuracy is lowered, and a device with rough control such as ON10FF control of a valve is used.

Further, in a batch manufacturing process, when a large number of chemical solutions are used, it is often impossible to perform cumulative measurement in the same container because these liquids have different physical properties. Therefore, the manufacturing system has a plurality of mixing containers as shown in FIG. 4, and liquid types that can be mixed are measured in the same container, and liquid types that cannot be mixed have a separate mixing container. Therefore, a preparation tank 10 (a type of mixing container) for reaction, preparation, etc. is required further downstream, resulting in a complicated system.

In this case, the above-mentioned preparation tank 10 may receive a required amount of the mixed liquid prepared in the mixing container, and as shown in FIG. 4, it is roughly distributed using valves ON10 FF, etc.

In a manufacturing system where the preparation tank 10 for reaction preparation etc. is fixed, when manufacturing a wide variety of products, it is necessary to install equipment according to the content of the products. Therefore, a large number of measuring tanks, preparation tanks and their attached piping, measuring tanks, preparation tanks and their attached piping measuring devices, control devices, attached valves, etc. are required. In this case, some equipment is used in some varieties but not in others, which is very
This results in a wasteful system and increases the initial cost of equipment. Furthermore, although multi-purpose manufacturing systems have been in demand in recent years, fixed manufacturing systems require changes to the piping system and associated equipment, resulting in a more complex manufacturing system than is currently the case. .

Therefore, in recent years, a mobile batch manufacturing system has been proposed in which the measuring tank or the preparation tank is made mobile to reduce the need for measuring devices.

However, when this system is adopted in a conventional weighing device, the measurement time differs depending on the size of the measurement setting value, and the larger the measurement setting value, the longer it takes to weigh, and the time required to transport the volume in a mobile manufacturing system. will be subject to restrictions. For this reason, in conventional manufacturing systems, a necessary number of weighing devices are installed in order not to impose restrictions on transportation time, but this contradicts the advantages of mobile manufacturing systems. In addition, such a system results in an even longer stay at the station (requires a large number of weighing devices due to the range of weighing settings, limitations on weighing time, weighing accuracy conditions, etc.) , operation time for connecting pipes, etc. increases).

In the manufacturing process of photographic tourism materials, photosensitive materials are handled and must maintain their optical properties, and the increase in the number of bonding points increases the complexity of the system, and changes in the conveyance cycle affect product performance.

Furthermore, as a dispensing device, each dispensing container has its own measuring device, regardless of the measuring and mixing device, and simple measuring methods such as liquid level meter or time metering that do not produce rough accuracy can be used.
A control method was in place.

[Problem that the invention seeks to solve]

Conventional liquid metering mixing and dispensing devices have the following drawbacks because the metering control is based on the assumption that the flow rate of the feed liquid is constant.

■ Weighing accuracy: Accuracy may not be guaranteed due to fluctuations in flow velocity due to disturbances or changes in liquid physical properties.

That is, in the case of gravity transfer, for example, if there is a large change in the amount of liquid remaining in the supply side container, the flow rate will be outside a certain range of conditions, resulting in poor measurement accuracy.

Additionally, this meant that it was necessary to limit the amount of liquid in the supply container within a certain range and to ensure that the amount of liquid was always above a certain amount, which caused a loss of the remaining liquid in the supply container and increased running costs. .

■ Measuring range: The measuring range is narrow.

The reason for this is that even if the metering is stopped, there is a flow amount due to the response delay of the system, and this amount is determined by the flow rate of the feed liquid, so if the flow rate is constant, narrowing the metering range will allow for an allowable flow amount. guaranteed. Therefore, the same
Even when measuring a liquid, if the measurement setting values differ greatly, measuring devices each having an appropriate measurement range are required, which increases the number of devices.

■Measuring time: Measuring time is affected by the measurement settings. If the metering setting value is small, the metering time will be short; if it is large, the metering time will be long. Therefore, a measuring device with a measuring time suitable for the manufacturing cycle is required depending on the measurement setting value, and the number of devices increases.

Furthermore, for the reasons mentioned above, conventional liquid metering, mixing and dispensing equipment requires a large number of independently controlled metering devices to be installed for each supply liquid container, and for each optimal metering time due to manufacturing capacity limitations. This made the system complex and required a large number of measuring devices.

In addition, the measuring accuracy of the dispensing device was not particularly high, and as a result, the mixed liquid had to be prepared extra, resulting in a large amount of wasted liquid and a long measuring time.

In addition, in conventional measuring methods, volumetric measuring methods such as oval flowmeters are often used, and during use, it is necessary to fill the piping with liquid, which has the problem of causing loss of raw material liquid. .

The object of the present invention was achieved based on the above circumstances, and
Based on the liquid measuring and mixing device (Japanese Patent Application No. 115891/1989) which has a metering control method using fuzzy control and a device for moving a liquid receiving container, which the present applicant has previously applied, flow rate fluctuations due to disturbances and changes in liquid physical properties can be controlled. We use a metering control device that achieves high-accuracy metering that is not affected by By configuring the system, we aim to simplify equipment, increase manufacturing capacity, and reduce raw material loss. ■ Reduce initial costs by reducing the number of devices. ■ Reduce maintenance man-hours by reducing the number of devices. ■ Reduce the number of devices. Reducing failures by improving reliability■ Our objective is to provide a liquid measuring, mixing and dispensing device that is highly economically effective in reducing running costs by reducing raw material loss.

[Means and effects for solving the problems] The above object of the present invention is to cumulatively measure a plurality of liquids from a plurality of supply containers, mix them in a mixing container, and supply the mixed liquids from the mixing container to a plurality of liquids. A device for metering and dispensing to a distribution container, which has an opening adjustment valve on the supply piping from the supply container and the distribution piping to the distribution container, and mixes the liquid from the supply container with the liquid from the mixing container into the distribution container. Closed-loop control in which a liquid measuring device is provided on the side of the mixing container, and the metering control device changes the opening degree of each of the opening adjustment valves based on fuzzy reasoning in response to the measured value of each supplied liquid and the measured value of distributed liquid. This is achieved by a liquid metering, mixing and dispensing device characterized in that it is a metering control device with a switching device and further includes a moving device for a liquid receiving container.

Components of the present invention will be explained in detail.

(]) Supply container: A container that stores the supply liquid to be metered. The capacity of the container requires a scale suitable for manufacturing. In the present invention, there is no limit to the remaining amount of the supply container, and theoretically it is possible to measure up to the remaining amount O. Furthermore, any liquid can be measured to a residual amount of 0, as long as it is not affected by the physical properties of the liquid (for example, viscosity, etc.) and has liquid physical properties that allow it to flow out.

(2) Opening adjustment valve: This is a flow rate control valve that has a number of opening adjustment valves corresponding to the number of supply containers, and changes the supply liquid flow rate over a wide range by changing the opening of the valve. Further, the flow rate characteristics of the valve are such that the valve is fully closed when the opening degree is around 0%, and the liquid flows from around 10%. A flow rate characteristic of 10% or more has characteristics other than quick open characteristics.

The drive may be, for example, an AC servo motor.

(3) Mixing container: A container with a capacity suitable for the manufacturing scale. For liquids that can be mixed, measure by cumulative measurement. If the liquids are washed after each transfer, even if they cannot be mixed, they can be measured individually in the same container. Install a stirrer and stir and mix in this container.

(4) Measuring device: A single measuring device installed on the side of the mixing container measures liquids from a plurality of supply containers. Cumulative measurement (addition/subtraction) is possible. Tank measurement methods such as load cells, differential pressure transmitters, and level meters are used. There are cases where it is attached to a mixing container and cases where the mixing container is placed on a weighing platform.

(5) Metering control device This is a closed-loop controlled precision metering device that changes the flow rate, and uses a control method based on fuzzy inference to make the opening degree of the opening adjustment valve variable. That is,
The initial opening degree of the valve is determined by the flow rate characteristics of the valve and the metering setting value, and the subsequent transition of the valve opening degree is performed by fuzzy control based on the supplied liquid metering value and the metering setting value. By providing a switching device, a plurality of liquids can be cumulatively measured (both addition and subtraction) in the same mixing container using at least one measuring device, and the number of devices can be reduced.

(6) Switching device: This is a device for controlling a plurality of supply container and distribution container opening adjustment valves with a second drive control device, and is part of the configuration of the metering control device. This eliminates the need to install a metering control section and a drive control section for each opening adjustment valve.

(7) Moving device: A moving device for transporting the mixing container. Transportation methods include automatic guided vehicles, conveyors, and the like. In addition, there are cases where the mixing container itself has a transport function as the conveyed object, and cases where the object is separated from the mixing container.

(8) Distribution container: A container that receives the required amount of mixed liquid, and is installed in an appropriate number depending on the manufacturing system.

The basic components of the present invention are as described above, but the main point of the present invention is to basically use a closed-loop metering control device that varies the flow rate, and that the metering control device performs fuzzy control.

The object of the present invention is to have a mixing container moving device, and to perform metering mixing and dispensing with one metering control device.

In addition, various auxiliary devices may be installed.

For example, a spray ball or the like is installed in each container for cleaning, and a switching valve is installed in the middle of the piping. Also, install a stirrer in each container for mixing. Furthermore, hot water from a constant temperature bath, etc. is always circulated to maintain heat.

[For production]

A device that cumulatively measures a plurality of liquids from a plurality of supply containers, receives them in a mixing container and mixes them, and then measures and distributes the mixed liquids from the mixing container to a plurality of distribution containers. The distribution piping to the distribution container has an opening adjustment valve, and the mixing container side has a measuring device for measuring the liquid from the supply container and the mixed liquid from the mixing container to the distribution container, and the metering control device measures each supply liquid. The metering control device is equipped with a switching device for closed loop control that changes the opening degree of each of the opening adjustment valves according to the measured value and the measured value of the distributed liquid according to fuzzy reasoning, and further includes a mixing container moving device. The characteristic liquid metering, mixing and dispensing device allows for precise metering and dispensing of various types of supply containers and dispensing containers using closed-loop control precision metering control equipment alone.
It is now possible to suffice with some opening adjustment valves for one type of supply container and distribution container regardless of the size of the measurement range, and for multiple supply containers that can be cumulatively weighed together and can be mixed at least. By using a connecting pipe, it is possible to measure with one mixing container (measuring tank) and one metering control device with a metering device, which greatly simplifies the device and also allows for easy flow of liquid from each supply container and into the distribution container. Measuring can be performed with high precision in a short time, and the amount of mixed liquid can be reduced.

Furthermore, by providing the mixing container with a moving device, (1) the supply piping for each supply container can be simplified without using a connecting pipe, reducing the need for cleaning and simplifying the equipment.

Since the mixing container (measuring tank or measuring pot) is movable, it is possible to distribute the measured liquid to all preparation tanks (a type of mixing container) without fixed piping, so you can reduce the number of mixing containers and improve equipment efficiency. It allows for flexibility. Therefore, when manufacturing a wide variety of products, it is possible to eliminate idle equipment on the mixing container side, and it is also possible to respond to prescription changes by minimizing the need for additional equipment. (2) Also, since the measuring cycle can be sped up by moving the mixing container (measuring pot), changes over time can be suppressed by small-volume preparation. ■ The tank for measuring the liquid from the supply liquid container can also be used as a reaction tank by attaching a stirrer.

[Embodiment]

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

As shown in FIG. 1, let us consider the case where there are M groups of liquids in which contamination of different liquid pipes is not a problem, and there are N chemicals in each group. Assume that there are a large number of products to be manufactured, but the total number of chemicals used for each product is below MXNXN. In conventional manufacturing systems, whether mobile or fixed, the weighing range, weighing time,
Due to measurement accuracy, a chemical supply container 1 and a weighing device 5 were required for each manufactured product even if they were of the same type, resulting in the number of devices exceeding MXNXN. However, in the present invention, since a closed-loop metering control device with variable flow rate is adopted and the metering control device performs fuzzy control, there is no need to worry about the metering range, metering time, and metering accuracy, and the supply container 1 The number of measuring devices 5 is sufficient, as long as there is no problem of liquid contamination.
A very small number of units determined based on the transport capacity is sufficient.

Here, A, 82 weighing devices 5 (load cells) are assumed. The number of supply containers 1 may be MXN, but since the number of measuring devices 5 is determined based on the chemical preparation time, manufacturing scale of the product, etc., the number of supply containers 1 must be greater than that. In some cases,

Each metering device has a metering control bag W6 having the contents of the control block shown in FIG. 11~N) or opening adjustment valve 2 (1~L) to the distribution container.
) is selected and output.

In other words, a large number of chemicals (1 to N
) and the dispensing containers (1 to 1) are measured in the same mixing container 4 (measuring pot).

As shown in FIG. 3, the opening adjustment valves 2 (11 to N) and (1 to L) each have a flow rate characteristic, for example, an equal percentage characteristic, and are fully closed when the valve opening is near 0%. , it has a characteristic that the liquid flows out from around 10%.

The metering control device 6 includes a filter calculation section 61, a fuzzy control section 62, and a drive control section 63.
The opening adjustment valve 2 (11-N).

Fuzzy control is performed based on the flow rate characteristics of (1 to L), the measured value obtained by the measuring device 5, and the measured setting value, and the opening of the opening adjustment valves 2 (11 to N) and (1 to L) is controlled. Control the degree.

Next, the operating process of the liquid metering, mixing and dispensing device of the present invention will be described.

The upper manufacturing control device issues an instruction to transfer the measuring pot A of the mixing container 4 to the station 1 for movement. Furthermore, an instruction is issued to the measuring device 5 (load cell A) to measure the chemical in a predetermined supply container 1 (for example, tank 12). The switching device 7 switches according to the system selection signal,
The opening adjustment valve 2 (12) and the shutoff valve 3 (12) of the selected tank 12 are provided so as to be controllable by the metering control device 6.

Further, the higher-level manufacturing control device issues an instruction to connect the supply container coupling device 12, which is an auxiliary device, to the coupling device section of the mixing container 4 (measuring bottle) A). When preparation for weighing is confirmed through such an initial state, a command to start weighing is given from a higher level. In response to the measurement start command, the shutoff valve 3 (
12) is opened, and a position command is transmitted from the metering control device 6 so that the opening adjustment valve 2 (12) has a predetermined opening.
) to set the valve boat of the opening adjustment valve 2 (12) at the indicated position, adjust the opening, and cause the flow of raw materials. At this time, the initial opening degree of the valve is determined by the fuzzy! The lJi section 62 calculates based on fuzzy rules. As a result, the raw materials in the tank 12 begin to be transferred to the mixing container 4. The weighing device 5 (load cell A) of the tank 12 detects the weight of the transferred raw material and feeds the value back to the weighing control device 6.

In the metering control device 6, the fuzzy control unit 62 calculates the deviation from the metering set value from the fed-back measured value of the supply liquid.
In addition to calculating the amount of change over time in the deviation, a value obtained by performing low-pass filter processing on these amounts is calculated. The fuzzy control unit 62 performs inference calculations based on fuzzy rules based on this calculated value, and obtains a valve opening that will provide an appropriate flow velocity in the next control cycle.

At this time, the membership function based on the fuzzy inference has a shape in which the axes corresponding to the physical quantities of the deviation amount and the deviation time change amount are divided into semi-logarithms if the sections of small physical quantities are divided into smaller sections. This is for the purpose of improving weighing accuracy and short time weighing, and if the amount of deviation is large,
This is because good controllability is not necessary, but it is necessary to improve control accuracy when the amount of deviation is small. This also applies to the -order filter processing function, in which when the amount of deviation, etc. is small, the amount of deviation, etc. of the first-order filter is used, the dynamic characteristics of the weighing detector are relaxed, and the weighing accuracy is improved.

After the measurement starts, when the measurement deviation becomes small, the opening adjustment valve 2 (
In 12), the opening degree is narrowed down to a minute flow velocity.

When the measurement deviation and the time change amount of the measurement deviation become small and the measurement deviation becomes less than a certain value, the measurement is stopped and the shutoff valve 3 (12
) moves in the fully closed direction. At this time, the flow velocity is minute and the amount of inflow is minute. Therefore, the amount of flow after the metering is stopped becomes small, and the metering accuracy is improved regardless of the flow velocity fluctuation. Furthermore, since the opening adjustment valve 2 (12) has the flow rate characteristics shown in FIG. 3, the valve opening changes at about 10% based on fuzzy inference calculations in the vicinity of zero deviation.

Therefore, even if there is mechanical backlash of the valve, the dead zone and fuzzy control system absorb the negative effects of the backlash and allow highly accurate metering. Furthermore, in the measurement range,
The operation of the opening adjustment valve changes depending on the measurement setting value and the process system, and regardless of the size of the measurement setting value, measurement can be performed with the same measuring device, expanding the measurement range. Also, during the measurement time, the operation pattern of the opening adjustment valve changes, and regardless of the magnitude of the measurement setting value, almost the same short-time measurement can be performed.

Once the above-mentioned operations are carried out in accordance with the product type and all the chemicals in the product are measured, the process moves on to the operation of transferring the liquid to the preparation tank (mixing container) in the downstream process, and further to the dispensing operation.

When a command to move to station 31 is issued from the higher level,
The autonomous vehicle transports the mixing container 4 (measuring pot A) to the station 31. Then, it is coupled to a piping connection device. If the preparation tank 10 as a distribution container is a moving device as shown in FIG. 1, this preparation tank IO can also be moved and connected to the lower part of the pipe connection device. After the connection is confirmed, the bottom valve of the mixing container 4 (measuring pot A) is controlled by the conveyance control device, opens, and the liquid is filled into the piping.

Furthermore, if a stirrer is added to the mixing container 4 (measuring pot) and the mixing container 4 is provided with functions such as mixing and reaction, and is positioned as a preparation tank, a more efficient system can be obtained.

Furthermore, the mixing device 4 is connected to the dispensing container through the station 3, thereby performing dispensing metering by subtractive metering.

In the embodiment, the measuring device 5 for weighing includes:
Although a load cell is used as an example, the same applies to other tank-type measuring instruments. In particular, if a differential pressure transmitter or the like is used in the tank, the mixing container (measuring pot) can be fixed to the self-propelled vehicle, making it easier to manufacture the mixing container, and eliminating the effects of vibrations and the like.

By using a metering control device that has the functions of additive metering in the mixing container 4 (measuring pot) and subtractive metering by attaching a metering device to the supply container 1 (tank), a wider range of precise metering becomes possible.

〔Effect of the invention〕

An apparatus for cumulatively measuring a plurality of liquids from a plurality of supply containers according to the present invention, receiving the liquids in a mixing container and mixing them, and distributing the mixed liquids from the mixing container to a plurality of distribution containers, the device comprising: The piping and the distribution piping to the distribution container have opening adjustment valves, the mixing container side has a metering device for the liquid from the supply container and the mixed liquid from the mixing container to the distribution container, and a metering control device is provided for each. This is a metering control device with a switching device for closed loop control that changes the opening degree of each of the opening adjustment valves based on fuzzy reasoning in response to the measured value of the supply liquid and the measured value of the distributed liquid, and further includes a mixing container moving device. The liquid metering, mixing and distributing device that is characterized by the following features enables high-accuracy metering that is not affected by flow velocity fluctuations caused by disturbances, and also enables rapid metering in a short time even over a wide metering range, making it possible to achieve metering mixing and metering. With one metering control device, distribution can be done precisely and quickly, with less liquid loss.Furthermore, equipment can be simplified and the number of metering devices can be reduced, increasing manufacturing capacity even with large-scale membrane equipment. Through large-scale preparation, we were able to improve product quality and reduce raw material loss. This resulted in lower initial costs, lower maintenance costs, lower running costs, and improved trust.

[Brief explanation of the drawing]

Figure 1 is a flow sheet of one embodiment of the liquid metering, mixing and distributing device of the present invention, Figure 2 is a block diagram of closed loop control according to the present invention, and Figure 3 is the flow rate characteristic of the opening adjustment valve used in the present invention. 4 and 5 are flow sheets of one embodiment of a conventional liquid metering, mixing and dispensing device. 1... Supply container 2... Opening adjustment valve 3... Closing valve 4... Mixing container 5... Measuring device 6...
・Weighing IIJ control device 7...Switching device 8...Drive motor 9...Automated guided vehicle

Claims (1)

[Claims] A device that cumulatively measures a plurality of liquids from a plurality of supply containers, receives them in a mixing container and mixes them, and then measures and distributes the mixed liquids from the mixing container to a plurality of distribution containers. It has an opening adjustment valve in the distribution piping to the distribution container,
A measuring device for measuring the liquid from the supply container and the mixed liquid from the mixing container to the distribution container is provided on the mixing container side, and the metering control device corresponds to each of the measured values of the supplied liquid and the measured value of the distributed liquid, and controls the respective opening adjustment valves. 1. A liquid metering, mixing and dispensing device, which is a metering control device with a switching device for closed-loop control that performs metering by changing the opening degree of the liquid by fuzzy reasoning, and further comprising a device for moving a mixing container.