JP6089423B2 - Liquid feeding device and control method thereof - Google Patents

Description

  The present invention relates to a liquid feeding device that outputs a liquid material and a control method thereof.

  A liquid feeding device that outputs a liquid material (liquid material) at the time of manufacturing various products is used.

  FIG. 8 is a block diagram showing a configuration of a general liquid delivery device 100.

  The liquid delivery apparatus 100 illustrated in FIG. 8 includes a storage unit 110, an output port 120, a delivery pipe 130, a liquid delivery part 140, an output pipe 150, a circulation pipe 160, and a switching part 170.

  The storage unit 110 stores a liquid material.

  The output port 120 outputs the liquid material to the outside of the liquid feeding device 100.

  The liquid feeding unit 140 sends the liquid material stored in the storage unit 110 to the delivery pipe 130. The liquid material delivered to the delivery pipe 130 is input to the switching unit 170.

  The switching unit 170 switches the output destination of the liquid material (hereinafter, referred to as “delivery liquid material”) sent to the delivery pipe 130 to either the output port 120 or the storage unit 110. When the output destination is the output port 120, the delivered liquid material is output from the output port 120 via the output pipe 150. On the other hand, when the output destination is the storage unit 110, the delivered liquid material circulates to the storage unit 110 via the circulation pipe 160.

  In order to stably manufacture a product using the liquid delivery device as described above, when a supply is required, a predetermined amount of liquid material is output accurately from the output port 120. It is necessary to control the output amount. Further, in order to control the output amount, it is necessary to measure the output amount with high accuracy.

  In Patent Document 1 (Japanese Patent Laid-Open No. 2005-288387), as shown in FIG. 9, a measurement unit 210 that measures the output pressure of the liquid material from the output port 120 is provided, and the pressure measured by the measurement unit 210 is A technique is disclosed in which the output amount is kept constant by controlling the liquid feed amount so as to be a predetermined pressure. However, in the technique disclosed in Patent Document 1, when the viscosity of the liquid material changes, the flow of the liquid material in the pipe changes, and the output amount changes even at the same output pressure. I can't control it.

  Therefore, in Patent Document 2 (Japanese Patent Laid-Open No. 2011-240281), as shown in FIG. 10, the amount of liquid material flowing through the output pipe 150 is measured between the output port 120 and the switching unit 170. A technique is disclosed in which a measuring unit 310 is provided and an integrated value of the measured liquid feeding amount measured by the measuring unit 310 is measured as an output amount.

  In the technique disclosed in Patent Document 2, since the output amount is measured based on the liquid feeding amount of the liquid portion flowing through the output pipe 150, the output amount measurement accuracy is improved even when the viscosity of the liquid material changes. be able to. However, in the technique disclosed in Patent Document 2, if an error is included in the measured liquid supply amount of the liquid material flowing through the output pipe 150, the error is also integrated in the output amount and the measurement accuracy of the output amount is lowered. .

  FIG. 11 is a diagram showing the relationship between the open / closed state of the output pipe and the amount of liquid material flowing through the output pipe. Hereinafter, the output pipe is in an open state means that the output destination of the liquid delivery material is an output pipe, and the output pipe is in a closed state means that the output destination of the liquid delivery material is a circulation pipe.

  As shown in FIG. 11, when the output pipe is switched from the closed state to the open state at time t <b> 111, a steep rise in the amount of liquid material flowing through the output pipe occurs. Further, when the output pipe is switched from the open state to the closed state at time t112, a steep fall of the amount of the liquid material flowing through the output pipe occurs. If a large fluctuation occurs in the liquid feed amount of the liquid material, the liquid feed amount cannot be measured accurately, and an error is included in the measured liquid feed amount. For this reason, in the technique disclosed in Patent Document 2, the measurement accuracy of the output amount is lowered due to an error included in the measured liquid feeding amount of the liquid material flowing through the output pipe.

  Note that the amount of the liquid delivery liquid flowing through the delivery pipe 130 varies when the output destination of the delivery liquid is switched. Therefore, in Patent Document 3 (Japanese Patent Application Laid-Open No. 6-231682), as shown in FIG. 12, the amount of liquid to be delivered flowing through the delivery pipe 130 between the liquid delivery unit 140 and the switching unit 170 is set. A technique for providing a measurement unit 410 for measurement is disclosed. Thereby, the measurement accuracy of the measured liquid supply amount of the liquid delivery material flowing through the delivery pipe 130 can be improved.

JP 2005-288387 A JP 2011-240281 A JP-A-6-231682

  As described above, the amount of the liquid material flowing through the delivery pipe varies when the output destination of the delivery liquid material is switched. For this reason, errors are also included in the measured amount of liquid flowing in the delivery pipe, and even if the output amount is measured based on the measured amount of liquid flowing in the delivery pipe, the measurement accuracy of the output amount is improved. It cannot be improved sufficiently.

  Also, when the flow of the liquid material changes due to clogging etc. in the circulation piping after the switching unit, the amount of liquid material flowing through the delivery piping and the output piping flows due to the pressure change in the piping The balance with the liquid feed amount may change. Even in such a case, the output amount cannot be accurately measured even if the output amount is measured based on the measured liquid delivery amount of the liquid material flowing through the delivery pipe.

  The objective of this invention is providing the liquid feeding apparatus which can improve the measurement precision of the output amount of a liquid substance, and its control method.

In order to achieve the above object, the liquid delivery device of the present invention comprises:
A liquid feeding device that outputs a liquid material stored in a storage unit from an output port,
A liquid feeding section for delivering the liquid material;
A switching unit that switches the output destination of the liquid material delivered by the liquid feeding unit to either the output port or the storage unit;
A measuring unit that measures the liquid feeding amount of the liquid material between the liquid feeding unit and the switching unit, and outputs a measurement result indicating the measured liquid feeding amount;
An average value and a change amount of the measured liquid feeding amount shown in the output of the measurement unit in a predetermined period are calculated, and the average value and a change amount of the measured liquid feeding amount are calculated from the output port in the predetermined period. And a controller that calculates the amount of the liquid material that has been output.

In order to achieve the above object, the method for controlling the liquid delivery device of the present invention comprises:
A liquid feeding part that sends out the liquid material stored in the storage part; and a switching part that switches an output destination of the liquid material sent out by the liquid feeding part to either the output port or the storage part. There is a method for controlling the liquid feeding device for outputting the liquid material from the output port,
Measure the liquid delivery amount of the liquid material between the liquid delivery unit and the switching unit,
An average value and a change amount of the measured liquid supply amount in a predetermined period are calculated, and the output from the output port in the predetermined period based on the calculated average value and change amount of the liquid supply amount Calculate the amount of liquid.

  According to the present invention, it is possible to improve the measurement accuracy of the output amount of the liquid material.

It is a block diagram which shows the structure of the liquid feeding apparatus of one Embodiment of this invention. It is a block diagram which shows the structure of the control part shown in FIG. It is a flowchart which shows the liquid feeding operation | movement of the liquid feeding apparatus shown in FIG. It is a figure which shows the piping pressure in the liquid feeding operation | movement of the liquid feeding apparatus shown in FIG. 1, an output amount, and the measured liquid feeding amount. It is a figure which shows the piping pressure in the liquid feeding operation | movement of the liquid feeding apparatus shown in FIG. 1, an output amount, and the measured liquid feeding amount. It is a figure which shows the change of the output amount and measurement liquid supply amount before and behind clogging in the circulation piping shown in FIG. It is a flowchart which shows the calculation operation | movement of the output amount of the control part shown in FIG. It is a flowchart which shows control operation | movement of the output amount of the control part shown in FIG. It is a block diagram which shows an example of a structure of a related liquid feeding apparatus. It is a block diagram which shows another example of a structure of the related liquid feeding apparatus. It is a block diagram which shows another example of a structure of the related liquid feeding apparatus. It is a figure for demonstrating the problem in the liquid feeding apparatus shown in FIG. It is a block diagram which shows another example of a structure of the related liquid feeding apparatus.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated with reference to drawings.

  FIG. 1 is a block diagram showing a configuration of a liquid delivery device 10 according to an embodiment of the present invention.

  1 includes a storage unit 11, an output port 12, a delivery pipe 13, a liquid delivery unit 14, an output pipe 15, a circulation pipe 16, a switching unit 17, a measurement unit 18, and the like. And a control unit 19.

  The storage unit 11 stores a liquid material.

  The output port 12 outputs the liquid material to the outside of the liquid feeding device 10.

  The liquid feeding unit 14 sends the liquid material stored in the storage unit 11 to the delivery pipe 13. The liquid material delivered to the delivery pipe 13 is input to the switching unit 17.

  The switching unit 17 switches the output destination of the delivery liquid material sent to the output pipe 13 to either the output port 12 or the storage unit 11. When the output destination is the output port 12, the liquid delivery material is output from the output port 12 via the output pipe 15. On the other hand, when the output destination is the storage unit 11, the delivery liquid is circulated to the storage unit 11 via the circulation pipe 16. Normally, the circulation pipe 16 has a smaller diameter than the output pipe 15.

  The measuring unit 18 is provided between the liquid feeding unit 14 and the switching unit 17, and measures the liquid feeding amount of the liquid material (liquid material delivered from the storage unit 11 by the liquid feeding unit 14) flowing through the delivery pipe 13. Then, the measured liquid feeding amount data is output to the control unit 19.

  The control unit 19 calculates the output amount of the liquid material output from the output port 12 based on the liquid supply amount of the liquid material flowing through the delivery pipe 13 indicated by the output of the measurement unit 18. In addition, the control unit 19 controls the driving of the liquid feeding unit 14 so that the calculated output amount becomes a predetermined amount.

  Next, the configuration of the control unit 19 will be described with reference to FIG.

  The control unit 19 illustrated in FIG. 2 includes a data acquisition unit 21, an output amount calculation unit 22, and a liquid feeding control unit 23.

  The data acquisition unit 21 acquires the current value data of the measured liquid feeding amount from the measurement unit 18. Further, the data acquisition unit 21 acquires switching timing data from the switching unit 17.

  The output amount calculation unit 22 calculates the output amount based on the current value data of the measured liquid delivery amount acquired by the data acquisition unit 21 and the data of the switching timing, and outputs the calculation result to the liquid delivery control unit 23. Here, the output amount calculation unit 22 calculates the average value of the measured liquid supply amount and the change amount of the liquid supply amount in a predetermined period (the output period in which the output destination of the liquid delivery material is the output pipe 15), and the calculated measurement. Based on the average value of the liquid feeding amount and the amount of change in the liquid feeding amount, an output amount that is the amount of the liquid material output from the output port 11 during the predetermined period is calculated. Details of the operation when calculating the output amount will be described later.

  The liquid feeding control unit 23 controls the driving of the liquid feeding unit 14 so that the output amount indicated by the output of the output amount calculating unit 22 matches a preset target output amount.

  Next, operation | movement of the liquid feeding apparatus 10 of this embodiment is demonstrated.

  FIG. 3 is a flowchart showing the liquid feeding operation of the liquid feeding device 10 of the present embodiment.

  For example, the control unit 19 receives an input of a set value for the liquid supply amount of the liquid material from the outside of the liquid supply apparatus 10. Moreover, the switching part 17 receives the input of a switching timing from the exterior of the liquid feeding apparatus 10, for example (step S31).

  Next, the control part 19 drives the liquid feeding part 13 so that the liquid substance of the inputted liquid feeding amount is sent out (step S32). The liquid feeding unit 13 sends the liquid material stored in the storage unit 11 to the delivery pipe 13. In step S <b> 32, the switching unit 17 sets the output destination of the liquid delivery material as the circulation pipe 16. Since the circulation pipe 16 is the output destination, the delivery liquid material is circulated to the storage unit 11 via the circulation pipe 16.

  At the switching timing, the switching unit 17 switches the output destination of the liquid delivery material to the output pipe 15. When the output pipe 15 is an output destination, the liquid delivery material is output from the output port 12 via the output pipe 15. At the next switching timing, the switching unit 17 switches the output destination of the delivery liquid material to the circulation pipe 16 (step S33). Thus, in step S33, the output and circulation of the liquid material are repeated.

  Next, the control unit 19 determines whether or not an input to end the liquid feeding has been input (step S34).

  When it is not input to end the liquid feeding (step S34: No), the switching unit 17 repeats the process of step S33.

  When it is input that the liquid feeding is to be ended (step S34: Yes), the control unit 19 notifies the switching unit 17 of that fact, and the switching unit 17 sets the output destination of the liquid delivery material to the circulation pipe 16. After switching to, the process ends.

  Next, the piping pressure, the output amount, and the measured liquid feeding amount during the liquid feeding operation will be described with reference to FIGS. 4A and 4B. Here, FIG. 4A shows a case where the output pressure is not sufficiently high, and FIG. 4B shows a case where the output pressure is sufficiently high.

  4A (a) and 4B (a) show the open / closed state of the output pipe 15. FIG. 4A (b) and 4B (b) show the pressure in the output pipe 15 (hereinafter referred to as output pressure) and the pressure in the circulation pipe 16 (hereinafter referred to as circulation pressure). In FIGS. 4A (b) and 4B (b), the solid line indicates the output pressure, and the dotted line indicates the circulation pressure. 4A (c) and 4B (c) show the output amount. FIG. 4A (d) and FIG. 4B (d) show the measured liquid feeding amount.

  4A (a) and 4B (a), the output pipe 15 is closed from time t41 to time t42 and from time t43 to time t44. Further, the output pipe 15 is in an open state from time t42 to time t43.

  If the output pressure is not sufficiently high at the time t42 when the output pipe 15 is switched from the closed state to the open state, it takes time until the output amount is stabilized as shown in FIG. 4A (c). In order to shorten this time, as shown in FIG. 4B (b), when the output pipe 15 is in an open state, the output pressure is increased so that the liquid material is pushed out instantaneously. It is necessary to raise the circulation pressure sufficiently during the closed state.

  Therefore, in the liquid feeding device, the circulation pipe 16 is usually made smaller in diameter than the output pipe 15 or the switching timing is adjusted to easily increase the circulation pressure and the output pressure. Therefore, as shown in FIGS. 4A (d) and 4B (d), when the output pipe 15 is closed, the measured liquid feeding amount decreases. On the other hand, when the output pipe 15 is in the open state, the measured liquid feeding amount increases. Accordingly, the measured liquid feeding amount varies (pulsates) between the circulation and output of the liquid material. Here, if the balance between the liquid supply amount of the output pipe 15 and the liquid supply amount of the circulation pipe 16 is always constant, the relationship between the transition of the average value of the measured liquid supply amount and the output amount is proportional.

  Next, a change in the measured liquid feeding amount when the flow of the liquid material in the circulation pipe 16 changes due to clogging or the like will be described with reference to FIG.

  5A shows the open / closed state of the output pipe 15, FIG. 5B shows the output amount, and FIG. 5C shows the measured liquid feed amount. In FIG. 5B and FIG. 5C, the solid line indicates the output amount and the measured liquid supply amount before the change in the flow of the liquid material in the circulation pipe 16, and the dotted line indicates the flow of the liquid material in the circulation pipe 16. The output amount and the measured liquid supply amount after changing the direction are shown.

  In FIG. 5, the output pipe 15 is closed from time t51 to time t52 and from time t53 to time t54. Further, the output pipe 15 is open from time t52 to time t53.

  When clogging occurs in the circulation pipe 16, it becomes difficult for the liquid material to flow in the circulation pipe 16 as compared with the normal time before the clogging occurs, and therefore, from time t51 to time t52, as shown in FIG. In the period, the measured liquid feeding amount is lower than that in the normal state. Therefore, the measured liquid feeding amount immediately after the output pipe 15 is opened at time t52 is lower than that at the normal time.

  Further, due to the clogging of the circulation pipe 16, the circulation pressure when the liquid material is circulated becomes larger than the normal time. Therefore, when the output pipe 15 is opened at time t52, more liquid material is pushed out than normal due to the influence of the increase in circulation pressure, and the measured liquid feeding amount increases. Accordingly, as shown in FIG. 5 (c), immediately after the output pipe 15 is opened at time t52, the measured liquid feeding amount is smaller than that at the normal time. It grows and gradually stabilizes.

  Here, the decrease in the measured liquid feeding amount due to clogging of the circulation pipe 16 immediately after the output pipe 15 is opened and the increase in the measured liquid feeding amount due to the increase in the piping pressure are offset, and the liquid material in the circulation pipe 16 is The average value of the measured liquid feeding amount before and after the change in flow may occur may be substantially constant. However, in practice, as shown in FIG. 5B, the output amount increases due to an increase in piping pressure. Therefore, even if the output amount is calculated based only on the average value of the measured liquid feeding amount, an accurate measurement result cannot be obtained.

  Therefore, in the present embodiment, not only the average value of the measured liquid feeding amount but also the change amount of the measured liquid feeding amount that is the difference between the maximum value and the minimum value of the measured liquid feeding amount during the predetermined period is used to determine the predetermined value. The amount of output in the period is calculated. Since the effect of the change in the flow of the liquid material in the circulation pipe 16 is reflected in the change amount of the measured liquid supply amount, the output amount is calculated by calculating the output amount based on the average value and the change amount of the measured liquid supply amount. The output amount can be accurately measured.

  Next, the output amount calculation operation by the control unit 19 will be described with reference to the flowchart shown in FIG.

  First, the data acquisition unit 21 acquires data of the current value of the measured liquid feeding amount from the measurement unit 18, and acquires switching timing data from the switching unit 17 (step S61).

  The output amount calculation unit 22 identifies the output period based on the switching timing data. Further, the output amount calculation unit 22 calculates the average value and the change amount of the measured liquid feeding amount during the output period (step S62).

  Next, the output amount calculation unit 22 calculates the output amount based on the average value and the change amount of the measured liquid feeding amount. Here, the output amount calculation unit 22 stores, for example, a relational expression between the output quantity shown in Expression (1), the average value of the measured liquid feeding amount, and the change amount, and the output quantity is calculated using this relational expression. Is calculated.

MFOut = α1 · MFAve + α2 · MFp−p + β Equation (1)
In Expression (1), MFOut indicates the output amount, MFave indicates the average value of the measured liquid feed amount, and MFp-p indicates the change amount of the measured liquid feed amount. Α1 and α2 are predetermined coefficients, and β is an offset. α1, α2, and β can be obtained in advance using, for example, multivariate analysis.

  When the flow of the liquid material in the output pipe 15 and the circulation pipe 16 changes, the flow of the liquid material in the output pipe 15 and the circulation pipe 16 is calculated even if the output amount is calculated based only on the average value of the measured liquid feed amount. The effect of this change is not reflected and the output amount cannot be calculated accurately. Therefore, by calculating the output amount based on the average value and the change amount of the measured liquid feeding amount, the output amount reflecting the change in the flow of the liquid material in the output pipe 15 and the circulation pipe 16 is calculated. Can do. Therefore, it is possible to improve the measurement accuracy of the output amount.

  Next, an output amount control operation by the control unit 19 will be described with reference to a flowchart shown in FIG. In FIG. 7, the same processes as those in FIG. 6 are denoted by the same reference numerals, and detailed description thereof is omitted.

  First, the liquid feeding control unit 23 receives an input of a set value of the target output amount from the outside of the liquid feeding device 10 (step S71).

  The data acquisition unit 21 acquires the current value data and the switching timing data of the measured liquid feeding amount (step S61), and the output amount calculation unit 22 calculates the output amount based on these data (step S62).

  The liquid feeding control unit 23 instructs the liquid feeding unit 14 so that the difference between the output amount calculated by the output calculating unit 22 and the set target output amount becomes zero (the liquid material to the sending pipe 13 (Sending amount) is calculated (step S72). In addition, the instruction value to the liquid feeding part 14 can be calculated by arithmetic control such as PID (Proportional Integral Differential) calculation.

  Next, the liquid feeding control unit 23 resets the calculated instruction value as a set value for the liquid feeding unit 14 (step S72).

  Next, the output amount calculation unit 22 determines whether or not an input to end liquid feeding has been input (step S73).

  When it is not input to end the liquid feeding (step S73: No), the process is repeated from step S61.

  When it is input that the liquid feeding is to be ended (step S73: Yes), the output amount calculation unit 22 ends the process.

  Thus, according to this embodiment, the liquid delivery apparatus 10 calculates the output amount based on the average value and the change amount of the measured liquid delivery amount of the liquid material flowing through the delivery pipe 13 in the output period.

  By calculating the output amount using the average value of the measured liquid feeding amount, for example, the output amount with the influence of the pulsation of the measured liquid feeding amount shown in FIGS. 4A (d) and 4 (d) is calculated. be able to.

  Further, when the flow of the liquid material in the circulation pipe 16 changes, the pressure in the pipe also changes, which affects the amount of liquid sent in the output pipe. As a result, as shown in FIGS. 5B and 5C, the output amount may change although the average value of the measured liquid feeding amount in the output period is substantially constant. In such a case, even if the output amount is calculated using only the average value of the measured liquid feeding amount, the output amount cannot be measured accurately. Therefore, in the present embodiment, the output amount is calculated based on the change amount of the measured liquid feeding amount in addition to the average value of the measured liquid feeding amount. The amount of change in the measured liquid supply amount reflects the effect of the change in the flow of the liquid material in the circulation pipe 16, so the output amount is calculated based on the average value and the change amount of the measured liquid supply amount. Thus, the output amount can be measured more accurately.

DESCRIPTION OF SYMBOLS 10 Liquid feeding apparatus 11 Storage part 12 Output port 13 Piping 14 Liquid feeding part 15 Output piping 16 Circulation piping 17 Switching part 18 Measuring part 19 Control part 21 Data acquisition part 22 Output amount calculation part 23 Liquid feeding control part

Claims (4)

A liquid feeding device that outputs a liquid material stored in a storage unit from an output port,
A liquid feeding section for delivering the liquid storage;
A switching unit that switches the output destination of the liquid material delivered by the liquid feeding unit to either the output port or the storage unit;
A measuring unit that measures the liquid feeding amount of the liquid material between the liquid feeding unit and the switching unit, and outputs a measurement result indicating the measured liquid feeding amount;
The average value and change amount of the measured liquid feed amount shown in the output of the measurement unit in the output period in which the output destination of the liquid material is the output port are calculated, and the calculated average value and change amount of the measured liquid feed amount And a controller that calculates the amount of the liquid material output from the output port during the output period . The liquid delivery device according to claim 1,
The liquid feeding device, wherein the control unit controls the driving of the liquid feeding unit so that a difference between the calculated output amount of the liquid material and a preset target output amount is small. A liquid feeding part for sending the liquid material stored in the storage part, and a switching part for switching the output destination of the liquid material sent by the liquid feeding part to either the output port or the storage part, There is a control method of a liquid feeding device for outputting the liquid material from the output port,
Measure the liquid delivery amount of the liquid material between the liquid delivery unit and the switching unit,
Calculate the average value and the amount of change of the measured liquid amount in the output period in which the output destination of the liquid material is the output port, and based on the calculated average value and amount of change of the liquid amount, A liquid feeding device control method, comprising: calculating an amount of the liquid material output from the output port during the output period .
A method for controlling a liquid delivery device according to claim 3,
A method for controlling a liquid feeding device, wherein the driving of the liquid feeding unit is controlled such that a difference between the calculated output amount of the liquid substance and a preset target output amount is reduced.

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