WO2023073808A1

WO2023073808A1 - Measuring device and measuring method

Info

Publication number: WO2023073808A1
Application number: PCT/JP2021/039491
Authority: WO
Inventors: 吉岡秀久; 後藤雅之; 林慶一; 山下智雄
Original assignee: 株式会社大気社
Priority date: 2021-10-26
Filing date: 2021-10-26
Publication date: 2023-05-04
Also published as: JP7197748B1; KR20230062465A; JPWO2023073808A1

Abstract

A measuring device (1) capable of measuring the concentration of solid material in a liquid (L) flowing through a certain flow passage (104) comprises a concentration measuring unit (2) capable of measuring the concentration of the solid material, and a guide tube (3) which has an opening portion (31) that opens in the flow passage (104), and which is capable of guiding liquid flowing in from the opening portion (31) to the concentration measuring unit (2) as a sample, wherein the opening portion (31) is configured to be capable of being installed with an attitude in which the opening portion opens facing a flow direction of the liquid flowing through the flow passage (104).

Description

Measuring device and method

The present invention relates to a measuring device and measuring method capable of measuring the concentration of solids in a liquid flowing through a predetermined flow path.

When painting an object to be painted such as an automobile body, it is common to perform a degreasing treatment to remove oil adhering to the surface of the object to be painted before the paint adheres to the object to be painted. . Typical degreasing methods include an immersion method in which the object to be coated is immersed in a degreasing solution such as a basic treatment solution, and a spraying method in which the object to be coated is sprayed with the degreasing solution. In either method, a device (piping, pump, etc.) for circulating the degreasing liquid is provided, and the degreasing liquid is often circulated and used repeatedly.

Contamination of the degreasing liquid becomes a problem when the degreasing liquid is used repeatedly. In particular, the iron powder adhering to the object to be coated is washed away by the degreasing liquid, separated from the object to be coated, and remains in the degreasing tank. The concentration gradually increases. If the iron powder contained in the degreasing solution adheres to the surface of the object to be coated and is carried over to the next process or later, it may cause defects such as bumps on the surface of the product after painting. Conventionally, techniques for removing the have been studied.

For example, the coating pretreatment apparatus disclosed in Japanese Patent Application Laid-Open No. 2002-322571 (Patent Document 1) is provided with a filter for removing impurities from the degreasing and chemical conversion treatment liquid filled in the dipping tank. Further, in the pretreatment washing apparatus disclosed in Japanese Patent Application Laid-Open No. 11-61469 (Patent Document 2), there is a reservoir in which the washing liquid sprayed on the vehicle body is collected, and the washing liquid in the reservoir is received and foreign matter is removed and purified. After that, there is provided a foreign matter removing circuit for sending out the purified liquid as a cleaning liquid.

In addition, the same phenomenon may be a problem for other solids of iron powder in the degreasing process. Examples of such solids include lint in the degreasing process, chemical sludge in the chemical conversion process, and iron powder in the electrodeposition process.

JP-A-2002-322571 JP-A-11-61469

The techniques of

Patent Documents

1 and 2 consider removing foreign substances contained in the degreasing liquid, but do not consider specifying the concentration of foreign substances (iron powder) contained in the degreasing liquid. rice field. For example, the conventional method of manually measuring the concentration of iron powder by periodically sampling the degreasing solution has been used, but this method requires continuous or frequent measurement of the concentration of iron powder. was difficult. Therefore, it has been difficult to identify the time when the treatment for removing foreign matter from the degreasing liquid should be performed.

Note that since the apparatus itself for measuring the concentration of solids such as iron powder is known, if the opening 91 of the measuring apparatus 9 is opened in the flow path of the degreasing liquid L as shown in FIG. A part of the circulating degreasing liquid L can be led to the concentration measuring unit 2, and the concentration of solids in the degreasing liquid L can be continuously measured. However, in the method of FIG. 6, the concentration of solids in the degreasing liquid L flowing near the wall surface of the channel may not sufficiently represent the average concentration of solids in the entire degreasing liquid L. It was difficult to measure. Therefore, the concentration of solids in the degreasing liquid L could not be accurately measured in some cases.

Therefore, it is required to realize a measuring device and a measuring method that can accurately measure the concentration of solids.

A measuring device according to the present invention is a measuring device capable of measuring the concentration of solids in a liquid flowing through a predetermined flow path, comprising: a concentration measuring unit capable of measuring the concentration of solids; and an opening in the flow path. a guide tube having an opening and capable of guiding the liquid, which has flowed through the opening, to the concentration measuring unit as a sample, wherein the opening faces the flow direction of the liquid flowing through the channel. It is characterized in that it can be installed in an open posture.

Further, a measuring method according to the present invention is a measuring method for measuring the concentration of solids in a liquid flowing through a predetermined flow path, wherein a guide tube having an opening at one end is and the other end of the guide tube is connected to a concentration measuring unit capable of measuring the concentration of solids, and the opening is connected to the guide tube. and guiding the liquid that has flowed into the unit to the concentration measuring unit as a sample, and measuring the concentration of solids in the sample.

According to these configurations, since the location where the opening serving as the sample inlet is provided is not limited to the wall surface of the channel, the sample can be collected from a position that can sufficiently represent the concentration of solids in the degreasing liquid L. Therefore, it is easy to accurately measure the concentration of solids.

Preferred embodiments of the present invention will be described below. However, the scope of the present invention is not limited by the preferred embodiments described below.

In one aspect of the measuring device according to the present invention, the concentration measuring unit includes a particle counter capable of measuring the number of particles in the sample, a flow meter capable of measuring the flow rate of the sample, and an arithmetic device. and the computing device is capable of executing a concentration specifying function of specifying the concentration of solids in the sample based on the indicated value of the particle counter and the indicated value of the flow meter.

According to this configuration, the flow rate of the sample can be specified along with the concentration of the solid matter. In addition, the concentration measurement unit can be configured by combining devices that are relatively easily available.

As one aspect, the measuring device according to the present invention includes a control valve capable of adjusting the flow rate of the sample flowing through the guide tube, and a current meter capable of measuring the flow rate of the liquid flowing through the flow path inside the tube. , a control device, wherein the control device specifies an inflow flow speed, which is the flow speed of the liquid flowing into the opening, based on the indicated value of the flow meter; and the inflow flow speed and and an inflow flow rate control function of controlling the opening degree of the control valve so that the flow rate in the pipe becomes equal to the flow rate in the pipe.

According to this configuration, since the inflow velocity and the in-pipe flow velocity are equal, the concentration of solids in the liquid flowing in from the opening easily matches the concentration of solids in the fluid flowing through the channel. This allows a more accurate measurement of solids concentration in the fluid.

As one aspect, the measuring device according to the present invention includes a control valve capable of adjusting the flow rate of the sample flowing through the guide tube, and a current meter capable of measuring the flow rate of the liquid flowing through the flow path inside the tube. , a control device, and an urging device capable of urging the sample flowing through the guide tube, wherein the control device controls the flow of the liquid flowing into the opening based on the indicated value of the flow meter. Controlling at least one selected from the opening degree of the control valve and the output of the urging device so that the inflow velocity is equal to the inflow velocity, and the inflow velocity is equal to the inflow velocity. and an inflow rate control function.

According to this configuration, the inflow velocity can be precisely controlled.

In one aspect of the measuring device according to the present invention, the opening may be configured to be installed in a position in which the opening is open to a portion of the channel where the main stream of the liquid flowing through the channel is formed. preferable.

As one aspect, the measuring device according to the present invention preferably further includes a cleaning medium supply device capable of supplying a cleaning medium from the middle of the guide pipe toward the opening.

According to this configuration, foreign matter adhering to the opening can be removed, so clogging of the opening can be prevented.

In the non-mainstream part of the liquid (the boundary layer that is susceptible to the friction of the channel wall surface), it is possible that the concentration of solids deviates from the concentration of solids in the entire liquid due to the influence of friction. Therefore, if the entire liquid is represented by a sample collected from the boundary layer, the concentration of solids in the entire liquid may not be accurately measured. Therefore, in the above configuration, the concentration of solids in the entire liquid can be accurately measured by opening the opening in the portion where the main stream of the liquid is formed and collecting a sample from the main stream.

As one aspect of the measuring method according to the present invention, it is preferable that the guide tube is installed at a position where the liquid flowing through the flow path is oriented downward or upward in the vertical direction.

In places where the direction of liquid flow is horizontal, solid matter may settle due to gravity. Therefore, there is a concentration gradient of solid matter in the vertical direction of the liquid, and it may be uncertain whether the sample collected from the opening correctly represents the entire liquid. Therefore, in the above configuration, by installing the guide pipe at a position where the flow direction of the liquid is vertically downward or upward, a sample can be collected from a position where the solid matter is not easily affected by gravity. Concentration can be measured correctly. In this case, the opening is vertically upward or downward.

Further features and advantages of the present invention will become clearer from the following description of exemplary and non-limiting embodiments described with reference to the drawings.

It is a figure which shows the structure of the degreasing tank to which the measuring apparatus which concerns on this embodiment is applied. It is a figure showing composition of a measuring device concerning this embodiment. It is a functional block diagram which shows the structure of the measuring device which concerns on this embodiment. It is a figure which shows the structure of the measuring apparatus which concerns on a modification. It is a figure which shows the modification of the installation location of a measuring device. It is a figure which shows a prior art.

An embodiment of a measuring device and a measuring method according to the present invention will be described with reference to the drawings. In the following, the measuring apparatus according to the present invention will be described as measuring apparatus 1 used for measuring the concentration of iron powder (which is an example of solid matter) in degreasing liquid L used in degreasing tank 100 of a painting facility. , and an example applied to a method for measuring the concentration of iron powder using the measuring device 1 will be described.

[Structure and function of degreasing tank]
First, as a premise for explaining the measuring device 1 according to the present embodiment, the configuration and functions of the degreasing tank 100 to which the measuring device 1 is applied will be explained. The degreasing tank 100 is a device for immersing an object to be coated (such as a vehicle body) in the degreasing liquid L stored in the degreasing tank 100 to chemically remove oil adhering to the surface of the object to be coated before coating. be. The degreasing tank 100 includes a main tank 101, an auxiliary tank 102, a nozzle device 103, a liquid supply channel 104, and a pump 105 (Fig. 1). As the degreasing liquid L, for example, an alkaline detergent or the like can be used.

The main tank 101 is a tank in which the degreasing liquid L is stored. The object to be coated is immersed in the degreasing liquid L stored in the main bath 101 to be degreased. The auxiliary tank 102 is a tank into which the degreasing liquid L overflowing from the main tank 101 flows. A liquid supply path 104 is connected to the bottom of the auxiliary tank 102 , and the degreasing liquid L flowing into the auxiliary tank 102 is supplied to the nozzle device 103 via the liquid supply path 104 . A pump 105 for urging the degreasing liquid L is provided in the middle of the liquid supply path 104 . The nozzle device 103 is provided inside the main tank 101 and can supply the degreasing liquid L to the main tank 101 .

With the above configuration, in the degreasing tank 100, the degreasing liquid L flows in the order of the main tank 101, the auxiliary tank 102, the liquid supply path 104 (pump 105), and the nozzle device 103, and the circulation path returning to the main tank 101 is established. formed. As a result, in the degreasing tank 100, while the degreasing liquid L is circulated, the degreasing of the objects to be coated that sequentially flow in can be repeated.

While the degreasing is performed as described above, the iron powder adhering to the surface of the object to be coated is washed away by the degreasing liquid L. As a result, the degreasing liquid L is mixed with iron powder. In the degreasing tank 100, the degreasing liquid L is circulated, and the degreasing liquid L is not actively replaced. rising. Since the iron powder contained in the degreasing liquid L may adhere to the surface of the object to be coated and be carried over to subsequent processes, it is not preferable to increase the concentration of the iron powder in the degreasing liquid L. Therefore, the concentration of iron powder in the degreasing liquid L is measured using the measuring device 1 according to the present embodiment, and the degreasing tank 100 is cleaned when the concentration exceeds a predetermined standard.

[Configuration of measuring device]
Next, the configuration of the measuring device 1 according to this embodiment will be described. A measuring apparatus 1 according to this embodiment includes a concentration measuring unit 2 capable of measuring the concentration of iron powder in a sample, a guide tube 3, a control valve 4, and a pump 5 (an example of an urging device). , a flowmeter 6, a compressed air supply device 7 (which is an example of a cleaning medium supply device), and a control device 8 (FIGS. 2 and 3). In this embodiment, the measuring device 1 is provided in the liquid supply path 104 (an example of a predetermined flow path) of the degreasing tank 100, and the degreasing liquid L (an example of a liquid) flowing through the liquid supply path 104 is ) will be described with respect to an example configured to be able to measure the concentration of iron powder inside.

The concentration measurement unit 2 is a unit that can measure the concentration of iron powder contained in the inflowing liquid sample. The concentration measurement unit 2 according to this embodiment has a particle counter 21 capable of measuring the number of particles in the sample, a flowmeter 22 capable of measuring the flow rate of the sample, and an arithmetic device 23 . The secondary side pipe 24 of the concentration measurement unit 2 is connected to the liquid supply path 104, and the sample after measurement returns to the liquid supply path 104. FIG.

The particle counter 21 is implemented as a known in-line measurement particle counter such as an electromagnetic induction type or a light scattering type, and is capable of outputting the total number of particles (in units of particles) detected in the sample in circulation as an indicated value. be. The flow meter 22 is implemented as a known liquid flow meter, and can output the flow rate (in units of mL/min) of the flowing sample as an indicated value.

The arithmetic unit 23 is implemented as a known computer (for example, PLC) having a CPU and a storage medium, and based on the indicated value of the particle counter 21 and the indicated value of the flow meter 22, the iron powder in the sample flowing A concentration identification function can be performed to identify the concentration of the Specifically, the cumulative value P (in units of particles) of the number of particles (indicated value of the particle counter 21), the length of the period T (in minutes) during which the cumulative value was obtained, and the flow rate F of the circulated sample ( mL/min), the iron powder concentration C (pieces/mL) in the sample is specified by Equation 1 below.
C=P/(TF) (1)

The guide tube 3 is a tubular body that can guide a liquid as a sample to the concentration measurement unit 2 . An opening 31 is provided at one end of the guide tube 3 , and the liquid (degreasing liquid L) flowing through the opening 31 flows through the guide tube 3 and is guided to the concentration measurement unit 2 . A control valve 4 and a pump 5 are provided in the middle of the guide pipe 3 , and a compressed air supply device 7 is provided in a form branching from the guide pipe 3 .

The opening 31 according to this embodiment is an opening provided on the side surface of the sampling tube 32 that constitutes one end portion of the guide tube 3 . The sampling tube 32 is configured to be inserted into the side surface of the tubular body 104a that constitutes the liquid supply path 104, and its dimensions are such that when the sampling tube 32 is inserted into the side surface of the tubular body 104a, the opening 31 is sized to be placed in the central portion of the liquid supply passage 104 . Here, the central portion of the liquid supply channel 104 means a region of the liquid supply channel 104 sufficiently separated from the wall surface (the actual portion of the tubular body 104a). It refers to a portion where the main flow of the liquid L (a portion that is not substantially affected by the viscosity) is formed.

By appropriately rotating the collection tube 32 inserted into the side surface of the tubular body 104a, the opening direction of the opening 31 can be made to face the circulation direction of the degreasing liquid L flowing through the liquid supply path 104. As shown in FIG. 2, the sampling tube 32 is installed at a location where the liquid supply path 104 (pipe body 104a) is provided along the vertical direction (the location indicated by the dashed line II in FIG. 1). , the degreasing liquid L flows upward at this point. Therefore, the opening 31 opens downward. Since the opening 31 faces (downward) the flow direction (upward) of the degreasing liquid L, part of the degreasing liquid L flowing through the liquid supply path 104 flows into the opening 31. Then, the degreasing liquid L can be guided to the concentration measuring unit 2 .

It is preferable that the location where the sampling pipe 32 is installed in the liquid supply path 104 is a location where the deviation of the flow velocity of the degreasing liquid L flowing through the liquid supply path 104 in the direction of the liquid supply path 104 is sufficiently small. For example, at a location downstream from a location where the flow velocity may change, such as the inlet or bent portion of the liquid supply channel 104, and at a location where the distance from the location where the flow velocity may change is 10 times or more the inner diameter of the liquid supply channel 104, A collection tube 32 is preferably installed.

The control valve 4 is a valve that can adjust the flow rate of the sample (degreasing liquid L) flowing through the guide pipe 3 . The degree of opening of the control valve 4 is determined according to an electrical signal input to the control valve 4, and the electrical signal is transmitted from the control device 8. As the control valve 4, a known control valve having such a function can be used. The control valve 4 may be always opened and its opening degree adjusted, or may be intermittently opened and its opening degree adjusted only when it is opened. In the former case, the measurement of solid content concentration is continuously performed, and in the latter case, the measurement of solid content concentration is performed intermittently.

The pump 5 is a pump capable of urging the sample (degreasing liquid L) flowing through the guide tube 3 . The output of the pump 5 is determined according to the electrical signal input to the pump 5 and such electrical signal is sent from the controller 8 . A known pump having such a function can be used as the pump 5 .

The compressed air supply device 7 is configured to supply compressed air (which is an example of a cleaning medium) from the middle of the guide pipe 3 toward the opening 31 . Implemented as a combination. When the control valve 72 is opened, compressed air flows toward the opening 31 . That is, the compressed air flows backward through the guide pipe 3 and is discharged from the opening 31 . As a result, foreign matter (such as iron powder) adhering to the opening 31 can be removed, so clogging of the opening 31 can be prevented. It is preferable to close the control valve 4 before opening the control valve 72 .

The opening and closing of the control valve 72 can be controlled by any method. For example, a method in which the control device 8 performs a function of controlling the opening and closing of the control valve 72, a method in which the opening and closing of the control valve 72 is controlled by a timer, and a method in which the opening of the control valve 4 reaches a predetermined set value. A method of opening the control valve 72 at times, a method of opening the control valve 72 when the inverter output frequency controlling the output of the pump 5 reaches a predetermined set value, and the like can be employed.

The flow meter 6 is a flow meter capable of measuring the flow velocity in the pipe, which is the flow velocity of the liquid (degreasing liquid L) flowing through the liquid supply path 104 . More specifically, the flow rate meter is configured and arranged to measure the flow rate of the degreasing liquid L in the central portion of the liquid supply passage 104 . The definition of the central portion of the liquid supply path 104 is the same as above.

The control device 8 is implemented as a known computer (for example, PLC) having a CPU and a storage medium, and is capable of executing an inflow velocity specifying function and an inflow velocity control function. The inflow velocity specifying function is a function of specifying the inflow velocity, which is the flow velocity of the liquid (degreasing liquid L) flowing into the opening 31 , based on the indicated value of the flow meter 22 . Specifically, based on the indicated value (mL/min unit) of the flow meter 22 and the opening area (cm ² unit) of the opening 31 stored in advance in the storage medium, the inflow velocity (m/sec unit) ).

The inflow velocity control function is a function that controls the opening of the control valve 4 or the output of the pump 5 so that the inflow velocity and the in-pipe flow velocity are equal. By performing such control, the inflow velocity and the in-pipe flow velocity become equal. It is easy to match the concentration of the iron powder, and the accuracy of the concentration measurement can be improved. Conversely, if there is a difference between the inflow velocity and the in-pipe flow velocity, the iron powder concentrations of the two may deviate. For example, when the inflow velocity is faster than the in-pipe flow velocity, in addition to the degreasing liquid L flowing in from the front of the opening 31, the degreasing liquid L flowing around it is also sucked into the opening 31. At this time, Iron powder, which has a higher density than the degreasing liquid L, is less likely to be sucked into the opening 31 than the degreasing liquid L. Therefore, a fluid containing a larger proportion of the degreasing liquid L than the degreasing liquid L flowing through the liquid supply passage 104 (that is, having a lower iron powder concentration) flows into the opening 31 . In this case, a measured value lower than the original concentration of iron powder in the degreasing liquid L flowing through the liquid supply passage 104 is obtained.

The computing device 23 and the control device 8 may be provided separately or may be the same. That is, for example, a single PLC may be configured to be capable of executing the concentration specifying function (function as arithmetic device 23), and the inflow velocity specifying function and inflow flow velocity control function (function as control device 8). .

〔Measuring method〕
Next, a method for measuring the concentration of iron powder in the degreasing liquid L using the measuring device 1 in this embodiment will be described.

First, the guide pipe 3 is installed in the liquid supply path 104 in such a posture that the opening 31 faces (downward) the flow direction (upward) of the degreasing liquid L. Also, the other end of the guide tube 3 is connected to the concentration measurement unit 2 (flow meter 22). A control valve 4 and a pump 5 are provided in the middle of the guide pipe 3, and a compressed air supply device 7 is provided in a form branched from the guide pipe 3. In addition, a current meter 6 is installed in the liquid supply path 104 .

When each part of the measuring device 1 is installed as described above, the degreasing liquid L flowing into the guide tube 3 from the opening 31 can be circulated through the guide tube 3 and guided to the concentration measuring unit 2. The concentration of iron powder inside can be measured. At this time, the control device 8 is caused to execute the inflow velocity specifying function and the inflow velocity control function to specify the inflow velocity, which is the flow velocity of the liquid (degreasing liquid L) flowing into the opening 31, and the liquid flowing through the liquid supply path 104. The opening of the regulating valve 4 and the output of the pump 5 are controlled so that the in-pipe flow velocity (indicated by the flow meter 6), which is the flow velocity of the (degreasing liquid L), matches the inflow velocity.

Further, as described above, since the guide pipe 3 is installed so that the opening 31 faces (downward) the flow direction (upward) of the degreasing liquid L, the width direction of the liquid supply path 104 The concentration of the iron powder in the degreasing liquid L is substantially uniform throughout. Therefore, the degreasing liquid L flowing from the guide pipe 3 is suitable as a sample representing the concentration of iron powder in the entire degreasing liquid L flowing through the liquid supply passage 104 . In this way, it is preferable to install the guide pipe 3 at a location where the degreasing liquid L flowing through the liquid supply path 104 is oriented downward or upward in the vertical direction.

Foreign matter (such as iron powder) adhering to the opening 31 can be removed by using the compressed air supply device 7 as appropriate (by appropriately opening the control valve 72) and flowing the compressed air toward the opening 31. , the clogging of the opening 31 can be prevented. Such an operation may be performed at an arbitrary timing based on human judgment, or at a timing determined to be necessary based on the indicated values of the particle measuring device 21 and the flow meter 22, It may be performed periodically at predetermined time intervals.

[Other embodiments]
Finally, another embodiment of the measuring device and measuring method according to the present invention will be described. It should be noted that the configurations disclosed in the respective embodiments below can also be applied in combination with configurations disclosed in other embodiments unless there is a contradiction. When describing the modification with reference to the drawings, the same reference numerals are given to the same constituent elements as in the above-described embodiment, and the description is simplified or omitted.

In the above embodiment, the configuration in which the opening 31 is provided on the side surface of the sampling tube 32 forming one end portion of the guide tube 3 has been described as an example. However, in the measuring device according to the present invention, the opening is not limited as long as it can be installed in a posture of opening facing the flow direction of the fluid flowing through the channel. For example, in the modification shown in FIG. 4, as a member constituting one end portion of the guide tube 3, instead of the extraction tube 32 of the above-described embodiment, a bent tube having an open end 33 (an example of an opening) is used. 34 is used. In this modification, the open end 33 can be opened to face the flow direction of the degreasing liquid L flowing through the liquid supply path 104 .

In the above-described embodiment, the configuration in which the sampling tube 32 is installed at a location where the liquid supply path 104 (pipe body 104a) is provided along the vertical direction (the location indicated by the dashed line II in FIG. 1) is taken as an example. explained as. However, in the measuring device according to the present invention, the position where the guide pipe is installed is not limited as long as the opening can be installed in a posture in which the opening faces the distribution direction of the liquid flowing through the channel. For example, in the modification shown in FIG. 5, the measuring device 1 according to the above embodiment is installed directly above the bottom opening 102a of the auxiliary tank 102 (the location indicated by the dashed line V in FIG. 1). In this modification, the sampling tube 32 is inserted from the side of the auxiliary tank 102 so that the opening 31 faces upward. Thereby, the opening 31 can be arranged so as to face the downward flow of the degreasing liquid L flowing into the bottom opening 102a (connected to the liquid supply passage 104).

So far, the examples in which the opening is open downward (FIGS. 2 and 4) and the example in which the opening is open upward (FIG. 5) have been described. The direction is not limited to the downward direction, but may be appropriately set as the direction opposite to the direction of flow of the liquid flowing through the channel. That is, the opening direction of the opening depends on the direction of liquid flow at the location where the measuring device according to the present invention is installed. For example, when the direction of liquid flow is horizontal, the opening direction of the opening is set in the horizontal direction opposite to the horizontal direction.

In the above embodiment, the configuration in which the secondary side pipe 24 of the concentration measurement unit 2 is connected to the liquid supply path 104 has been described as an example. However, in the measuring device according to the present invention, the connection destination of the secondary side pipe of the concentration measuring unit is not limited. Further, when the secondary side pipe of the concentration measuring unit is connected to the liquid circulation system, the position is not limited. For example, the secondary pipe 24 is connected downstream of the opening 31 in the embodiment of FIG. 2 , and the secondary pipe 24 is connected upstream of the opening 31 in the modified example of FIG. 5 .

In the above embodiment, the configuration in which the opening 31 can be arranged in the central portion of the liquid supply path 104 has been described as an example. However, in the present invention, the relative positions of the opening and the channel are not limited. For example, in processes where some degree of measurement error is acceptable, the opening may be provided in the portion of the feed channel near the wall where the boundary layer is formed.

In the above embodiment, the configuration in which the compressed air supply device 7 is provided and the opening 31 can be cleaned by supplying compressed air to the opening 31 has been described as an example. However, in the present invention, the presence or absence of the cleaning medium supply device is optional. Further, when a cleaning medium supply device is provided, the cleaning medium is not limited to compressed air, and may be, for example, liquid of the same kind as the liquid flowing through the flow path, water, or the like. The configuration of the cleaning medium supply device can be appropriately selected according to the cleaning medium to be used.

In the above embodiment, the configuration in which the concentration measurement unit 2 has the particle measuring device 21, the flow meter 22, and the arithmetic device 23 has been described as an example. However, in the measurement apparatus according to the present invention, the specifications of the concentration measurement unit are not particularly limited as long as the concentration of solids in the sample can be measured. For example, instead of using a device that specifies the concentration C of solids in the sample using formula (1) as in the above embodiment (in units of units/mL), the concentration C of solids in the sample is used as an indicated value. Any device capable of output may be used.

In the above-described embodiment, as the inflow velocity control function, the configuration that can execute the function of controlling the opening degree of the control valve 4 or the output of the pump 5 so that the inflow velocity and the in-pipe flow velocity are equal has been described as an example. . However, the measurement device according to the invention may not be able to perform the inflow flow rate control function. In this case, the inflow velocity depends on the intra-pipe flow velocity and is determined by circumstances, and more specifically, the inflow velocity tends to be lower than the intra-pipe flow velocity. At this time, the measured value of the concentration of solids tends to be higher than the concentration of solids in the liquid actually flowing through the channel. For this reason, it is preferable to be able to perform the inflow flow rate control function in terms of more accurate measurement of the concentration of solids, but depending on the required measurement accuracy, this function may be omitted. In addition, in the configuration capable of executing the inflow velocity control function, the components to be controlled are not limited as long as the inflow velocity can be controlled. For example, instead of the above configuration, the configuration may be such that the pump 5 is omitted, and only the opening of the control valve is a candidate for the controlled object.

In the above embodiment, the configuration in which the flow meter 6 for measuring the flow velocity inside the pipe is provided has been described as an example. However, the measuring device according to the present invention does not have to be equipped with a current meter. For example, if the inflow velocity control function is omitted as described above, the current velocity meter can be omitted because there is no need to measure the in-pipe flow velocity. Further, even when the inflow velocity control function is executable, the in-pipe flow velocity may be specified based on actual measurements of other parameters instead of providing the velocity meter. Examples of parameters that can be converted into the in-pipe flow velocity include the flow rate of the liquid flowing through the channel, the dynamic pressure in the vicinity of the opening, and the like. In this case, a measuring instrument capable of measuring parameters to be converted is installed.

When the dynamic pressure in the vicinity of the opening is measured, as an embodiment of the inflow velocity control function, the biasing device can be controlled so that the dynamic pressure is equal to or less than the threshold. Therefore, this aspect of the present invention further comprises a pressure gauge capable of measuring the dynamic pressure at the opening, a control device, and an urging device capable of urging the sample flowing through the guide tube, wherein the control device It may be possible to implement an inlet flow rate control function that controls the output of the biasing device based on the pressure gauge reading.

The present invention does not preclude use in combination with devices or equipment that perform further operations using the concentration of solids in a liquid specified by the measuring device and measuring method according to the present invention. For example, in the above-described embodiment, a sub-channel having a solid removal device is provided separately from the liquid supply channel 104, and the degreasing liquid L is supplied when the measured concentration of solids exceeds a predetermined threshold value. Instead of the liquid path 104, it may be configured to flow through a sub-flow path. In this case, a known device such as a filter type or a cyclone type can be used as the solid matter removing device. Note that the downstream outlet of the sub-channel can be provided in the auxiliary tank 102, for example.

Regarding other configurations, it should be understood that the embodiments disclosed in this specification are illustrative in all respects, and that the scope of the present invention is not limited by them. Those skilled in the art will easily understand that modifications can be made as appropriate without departing from the scope of the present invention. Therefore, other embodiments modified without departing from the gist of the present invention are naturally included in the scope of the present invention.

The present invention can be used, for example, when measuring the concentration of solids in fluids used in various processes of painting equipment.

Reference Signs List 1: measuring device 2: concentration measuring unit 21: particle measuring device 22: flow meter 23: computing device 3: guide tube 31: opening 32: sampling tube 33: open end (modification)
34: bent pipe (modification)
4: Control valve 5: Pump 6: Velocity meter 7: Cleaning medium supply device 71: Air compressor 72: Control valve 8: Control device 9: Conventional measuring device 91: Opening of conventional measuring device 100: Degreasing tank 101: Main tank 102: Auxiliary tank 102a: Bottom opening of auxiliary tank 103: Nozzle device 104: Liquid supply path 104a: Pipe body 105: Pump L: Degreasing liquid

Claims

A measuring device capable of measuring the concentration of solids in a liquid flowing through a predetermined flow path,
a concentration measuring unit capable of measuring the concentration of solid matter;
a guide tube having an opening that opens to the flow channel and capable of guiding the liquid flowing from the opening to the concentration measurement unit as a sample;
The measuring device is configured such that the opening can be installed in a posture in which the opening faces the flow direction of the liquid flowing through the channel.
The concentration measurement unit is
a particle counter capable of measuring the number of particles in the sample;
a flow meter capable of measuring the flow rate of the sample;
a computing device;
2. The measuring device according to claim 1, wherein the computing device is capable of executing a concentration specifying function of specifying the concentration of solids in the sample based on the indicated value of the particle counter and the indicated value of the flow meter. .
a control valve capable of adjusting the flow rate of the sample flowing through the guide tube;
a current meter capable of measuring the flow velocity in the pipe, which is the flow velocity of the liquid flowing through the channel;
and a controller,
The control device
an inflow velocity specifying function for specifying an inflow velocity, which is the flow velocity of the liquid flowing into the opening, based on the indicated value of the flow meter;
3. The measuring device according to claim 2, capable of executing an inflow velocity control function of controlling the degree of opening of the control valve so that the inflow velocity and the in-pipe flow velocity become equal.
a control valve capable of adjusting the flow rate of the sample flowing through the guide tube;
a current meter capable of measuring the flow velocity in the pipe, which is the flow velocity of the liquid flowing through the channel;
a controller;
an urging device capable of urging the sample flowing through the guide tube,
The control device
an inflow velocity specifying function for specifying an inflow velocity, which is the flow velocity of the liquid flowing into the opening, based on the indicated value of the flow meter;
and an inflow velocity control function of controlling at least one selected from the opening degree of the control valve and the output of the urging device so that the inflow velocity and the in-pipe flow velocity become equal. 2. The measuring device according to 2.
The measuring device according to any one of claims 1 to 4, further comprising a cleaning medium supply device capable of supplying a cleaning medium from the middle of the guide pipe toward the opening.
The measurement according to any one of claims 1 to 5, wherein the opening is configured to be installed in a position in which it opens to a portion of the channel where the main stream of the liquid flowing through the channel is formed. Device.
A measurement method for measuring the concentration of solids in a liquid flowing through a predetermined flow path,
A guide tube having an opening at one end is installed in such a manner that the opening faces the direction of flow of the liquid flowing through the flow path, and the other end of the guide tube is set to the concentration of solids. to a measurable concentration measurement unit,
A measuring method comprising: guiding the liquid, which has flowed into the guide pipe from the opening, to the concentration measuring unit as a sample, and measuring the concentration of solids in the sample.
The measuring method according to claim 7, comprising installing the guide pipe at a position where the direction of flow of the liquid flowing through the channel is vertically downward or upward.