JP2009115554A - Liquid concentration measuring device and liquid concentration measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid concentration measuring device capable of measuring a liquid, especially involved in a moving object to be measured at high precision, and a liquid concentration measuring method. <P>SOLUTION: A moisture concentration measuring device 100 includes: a first light projecting part 111, arranged to be separated from the surface of a paste 2 which contains moisture by a first measurement distance T1, for projecting laser light 101; a first light receiving part 112 for receiving the laser light 101 projected from the first light projecting part 111; a second light projecting part 121, arranged separately from the surface of the paste 2 by a second measurement distance T2, for projecting laser light 102; a second light receiving part 122 for receiving the laser light 102 projected by the second light projecting part 121; a concentration computing device 130 for computing the second liquid concentration C2 based on the intensity of the laser light 102 while computing the first liquid concentration C1 based on the intensity of the laser light 101; and an analysis device 141 for computing the moisture concentration included in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a technique for measuring the concentration of a liquid contained in a measurement object.
More specifically, the present invention relates to a technique for measuring the concentration of a liquid contained in a measurement object by measuring the concentration of the liquid evaporated in the atmosphere from the measurement surface (surface) of the measurement object.

  Conventionally, a dry mass method, a Karl Fischer method, a dielectric constant method, an infrared method, and the like are known as techniques for measuring the concentration of water contained in a measurement object.

  In the dry mass method, the mass of a measurement object including moisture is measured, and then the measurement object is dried by heating or the like. Subsequently, the mass of the dried measurement object is measured, and the measurement object is measured. This is a method of calculating the mass of moisture contained in the measurement object based on the change in mass before and after drying.

  The Karl Fischer method uses a Karl Fischer solution (solution consisting of iodine, sulfur dioxide, base, and solvent) that selectively and quantitatively undergoes an electrolytic oxidation reaction with moisture, and measures the amount of electricity required for the electrolytic oxidation reaction. This is a method for measuring the amount of moisture contained in the measurement object.

The dielectric constant method uses the difference in the dielectric constant between the measurement object and moisture (difference in relative dielectric constant), and the apparent measurement object changes as the amount of water contained in the measurement object changes. In this method, the amount of moisture contained in the measurement object is measured by measuring the dielectric constant.
The dielectric constant method is classified into a plurality of measurement methods with different types of sensors used, for example, an electromagnetic wave method, a resonance method, a complex dielectric constant method, a TDR (Time Domain Reflectometry) method, an ADR (Amplitude Domain Reflectometry) method, and the like.

  The infrared method uses the property that a component of a specific wavelength is absorbed when the moisture is irradiated with infrared rays, and measures the amount of moisture contained in the measurement object by measuring the intensity of infrared rays of the absorbed wavelength. Is the method.

In addition to the above method, there is known a method for detecting the presence of a water droplet by a change in electrical resistance between electrodes due to the water droplet. For example, as described in Patent Document 1.
The water droplet detection sensor described in Patent Document 1 is obtained by forming a hydrophilic chemical adsorption film on the surface of a substrate provided with a pair of electrodes. The water droplets adsorbed on the chemical adsorption film of the water droplet detection sensor spread quickly along the chemical adsorption film and conduct between the pair of electrodes, so that the electrical resistance between the electrodes changes.

  However, the dry mass method and the Karl Fischer method have the problems that the measurement object after the measurement is substantially denatured and the time required for the measurement is long. It is difficult to apply to applications that measure sequentially (by 100% inspection).

  The dielectric constant method must be in contact with the measurement object to be used, and is difficult to apply to a measurement object that is moving (not stationary). In addition, the dielectric constant method has a long response time of the sensor used, for example, a few tens of seconds, so that it is difficult to apply to a use for measuring the moisture concentration in real time.

The infrared method can perform measurement without contact with the measurement object, does not substantially change the measurement object, and has good response at the time of measurement (response time is very short). Excellent in terms.
However, the infrared method has a problem that it is generally difficult to apply when the measurement object is made of a material that does not transmit infrared light.

  In the water droplet detection sensor of Patent Document 1, it is difficult to detect the presence or absence of water droplets in real time because the adsorption of water droplets to the chemical adsorption film is a rate-determining condition for the response of the sensor.

  As a method of measuring the amount of moisture contained in a moving measurement object (in particular, a measurement object that does not transmit light) to solve the above problems, (A) a gas containing moisture evaporated from the measurement object And measuring the moisture concentration of the sampling gas by bringing the collected gas (sampling gas) into contact with a sensor using a dielectric constant method (for example, a type that adsorbs moisture to a ceramic or polymer film) (B) Collecting a gas containing moisture evaporated from the object to be measured, cooling the mirror surface while bringing the sampling gas into contact with the mirror surface, and measuring the moisture concentration of the sampling gas by measuring the temperature at which the mirror surface is condensed And (C) a method of irradiating a gas containing moisture evaporated from a measurement object with infrared rays and measuring the concentration of moisture contained in the gas.

However, the above methods (A) and (B) have the following problems.
In the methods (A) and (B) described above, the measurement accuracy decreases when condensation occurs in the sampling gas transfer path.
In the methods (A) and (B), it takes a time lag from the sampling gas being collected until it reaches the sensor (actually the water concentration is measured), and the water concentration can be measured in real time. Have difficulty.
In the methods (A) and (B) described above, the reliability of the measurement results decreases when the sampling gas is mixed inside the transport path.
The above methods (A) and (B) can measure only the moisture concentration in a very narrow region called the sampling gas sampling position. Therefore, when measuring the moisture concentration distribution, sampling gas is sampled at a plurality of locations. Therefore, the water concentration must be measured, and the apparatus becomes large or complicated.

Further, in the method (A), in addition to the above problems, the response time of the sensor used and the time required for pretreatment (such as dust removal) performed before the sampling gas is brought into contact with the sensor also become a time lag. The problem is that it is difficult to measure the water concentration in real time.
In addition to the above problem, the method (B) above cannot perform the next measurement until the water droplets once condensed evaporate, so that it is difficult to apply the method to sequentially measure a plurality of objects in a short time. Has the problem of being.

In addition, the method (C) can be applied regardless of whether or not the measurement object transmits infrared light because the gas containing moisture evaporated from the measurement object is irradiated with infrared light. However, there is a problem that the measurement accuracy is low simply by irradiating the gas containing moisture evaporated from the measurement object with infrared rays.
In particular, the optical path of infrared rays applied to the gas containing moisture evaporated from the measurement object is not only the measurement area (area occupied by the gas containing moisture evaporated from the measurement object), but also dead space (area outside the measurement area) ), There is a problem that the measurement accuracy of the moisture concentration is further lowered.

As a method for solving the problem of the dead space, (i) a method of purging a gas not containing moisture in the dead space, or (ii) an optical component (a glass block or other solid or liquid that transmits infrared rays) in the dead space A method of arranging these can be considered.
However, when the gas purged in the dead space flows into the measurement region, the above method (i) decreases the measurement accuracy, and the method (ii) may depend on the measurement environment (such as when the measurement object is hot). There is a problem that it is difficult to arrange the optical component in the dead space.
JP-A-8-122291

  In view of the circumstances as described above, the present invention provides a liquid concentration measuring apparatus capable of accurately measuring a liquid (water, organic solvent, oil, etc.) contained in a measurement object (particularly a moving measurement object) and A liquid concentration measurement method is provided.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, in claim 1,
A first light projecting unit that projects laser light that is spaced apart from the measurement surface of the measurement object including the liquid by a first measurement distance and parallel to the measurement surface;
A first light receiving unit that receives the laser light projected by the first light projecting unit and detects the intensity of the laser light;
A second light projecting unit that projects a laser beam parallel to the measurement surface separated from the measurement surface of the measurement object by a second measurement distance greater than the first measurement distance;
A second light receiving unit that receives the laser light projected by the second light projecting unit and detects the intensity of the laser light;
A first liquid concentration calculation unit that calculates a first liquid concentration that is a liquid concentration at a position separated from the measurement surface of the measurement object by a first measurement distance based on the intensity of the laser light detected by the first light receiving unit. When,
A second liquid concentration calculation unit that calculates a second liquid concentration that is a liquid concentration at a position separated from the measurement surface of the measurement object by a second measurement distance based on the intensity of the laser light detected by the second light receiving unit. When,
A measurement object that calculates the concentration of the liquid contained in the measurement object based on the first liquid concentration calculated by the first liquid concentration calculation unit and the second liquid concentration calculated by the second liquid concentration calculation unit. A liquid concentration calculator,
It comprises.

In claim 2,
The wavelengths of the laser beams projected by the first light projecting unit and the second light projecting unit both include wavelengths that are absorbed by the liquid contained in the measurement object.

In claim 3,
The laser light projected by the first light projecting unit and the laser light projected by the second light projecting unit are parallel to each other,
A plane including the laser light projected by the first light projecting portion and the laser light projected by the second light projecting portion is orthogonal to the measurement surface of the measurement object.

In claim 4,
The first measurement distance T1 is set according to the following procedures (a) to (d).
(A) Based on the following Equation 1, using the conveyance speed U of the measurement object, the width W of the measurement object viewed from the conveyance direction of the measurement object, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. To calculate the Reynolds number Re.
(B) When the calculated Reynolds number Re satisfies the relationship represented by the following formula 2, it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, and the calculated Reynolds number When Re satisfies the relationship expressed by the following equation (3), it is determined that the flow state of the region facing the measurement surface of the measurement object is turbulent.
(C) When it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, the boundary layer thickness δ is calculated based on the following Equation 4 to measure the measurement object: When it is determined that the flow state of the region facing the surface is turbulent, the boundary layer thickness δ is calculated based on the following Equation 5.
(D) Said 1st measurement distance T1 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 6.

  In Claim 5, said 2nd measurement distance T2 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 7.

In claim 6,
The measurement object liquid concentration calculation unit includes:
The first liquid concentration C1 calculated by the first liquid concentration calculator, the optical path length L1 of the laser light projected from the first light projector, and the second liquid calculated by the second liquid concentration calculator Using the density C2 and the optical path length L2 of the laser light projected from the second light projecting unit, the correction liquid density Cr that is the correction value of the first liquid density C1 is calculated based on the following formula 8. Is.

In claim 7,
The measurement object liquid concentration calculation unit includes:
By comparing the relationship between the correction liquid concentration Cr stored in advance and the concentration of the liquid contained in the measurement object with the calculated correction liquid concentration Cr, the concentration of the liquid contained in the measurement object is determined. Is to be calculated.

In claim 8,
The measurement object liquid concentration calculation unit includes:
By comparing the calculated corrected liquid concentration Cr with a threshold value stored in advance, it is determined whether or not the concentration of the liquid contained in the measurement object is within a preset desired range.

In claim 9,
A laser beam that is spaced from the measurement surface of the measurement object including the liquid by a first measurement distance and is parallel to the measurement surface is projected, the laser beam is received to detect the intensity of the laser beam, and the measurement A laser beam that is spaced apart from the measurement surface of the object by a second measurement distance greater than the first measurement distance and is parallel to the measurement surface is projected, the laser beam is received, and the intensity of the laser beam is detected. Laser light projecting / receiving process,
The liquid concentration is projected at a first measurement distance from the measurement surface of the measurement object, and the liquid concentration at a position away from the measurement surface of the measurement object by the first measurement distance is based on the intensity of the received laser beam. While calculating a certain first liquid concentration, the second liquid is projected from the measurement surface of the measurement object by a second measurement distance, and the second liquid is measured from the measurement surface of the measurement object based on the intensity of the received laser beam. A first liquid concentration / second liquid concentration calculating step of calculating a second liquid concentration that is a liquid concentration at a position separated by a measurement distance;
A measurement object liquid concentration calculation step of calculating a concentration of a liquid contained in the measurement object based on the first liquid concentration and the second liquid concentration calculated in the first liquid concentration / second liquid concentration calculation step; It comprises.

In claim 10,
The wavelength of the laser beam projected at a first measurement distance from the measurement surface of the measurement object and the wavelength of the laser light projected at a second measurement distance from the measurement surface of the measurement object are either Includes a wavelength absorbed by the liquid contained in the measurement object.

In claim 11,
A laser beam projected at a first measurement distance from the measurement surface of the measurement object and a laser beam projected at a second measurement distance from the measurement surface of the measurement object are parallel to each other. Yes,
A plane including laser light projected at a first measurement distance away from the measurement surface of the measurement object and a laser light projected at a second measurement distance away from the measurement surface of the measurement object is the plane It is orthogonal to the measurement surface of the measurement object.

In claim 12,
The first measurement distance T1 is set according to the following procedures (a) to (d).
(A) Based on the following Equation 1, using the conveyance speed U of the measurement object, the width W of the measurement object viewed from the conveyance direction of the measurement object, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. To calculate the Reynolds number Re.
(B) When the calculated Reynolds number Re satisfies the relationship represented by the following formula 2, it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, and the calculated Reynolds number When Re satisfies the relationship expressed by the following equation (3), it is determined that the flow state of the region facing the measurement surface of the measurement object is turbulent.
(C) When it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, the boundary layer thickness δ is calculated based on the following Equation 4 to measure the measurement object: When it is determined that the flow state of the region facing the surface is turbulent, the boundary layer thickness δ is calculated based on the following Equation 5.
(D) Said 1st measurement distance T1 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 6.

In claim 13,
Said 2nd measurement distance T2 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 7.

In claim 14,
In the measurement object liquid concentration calculation step,
The first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculating step, the optical path length L1 of the laser light projected at a first measurement distance from the measurement surface of the measurement object, The second liquid concentration C2 calculated in the first liquid concentration / second liquid concentration calculating step and the optical path length L2 of the laser beam projected at a second measurement distance from the measurement surface of the measurement object are set. The correction liquid concentration Cr, which is the correction value of the first liquid concentration C1, is calculated based on the following equation (8).

In claim 15,
In the measurement object liquid concentration calculation step,
By comparing the relationship between the correction liquid concentration Cr stored in advance and the concentration of the liquid contained in the measurement object with the calculated correction liquid concentration Cr, the concentration of the liquid contained in the measurement object is determined. Is to be calculated.

In claim 16,
In the measurement object liquid concentration calculation step,
By comparing the calculated corrected liquid concentration Cr with a threshold value stored in advance, it is determined whether or not the concentration of the liquid contained in the measurement object is within a preset desired range.

  The present invention has an effect that it is possible to accurately measure a liquid contained in a measurement object.

  Hereinafter, a water concentration measuring apparatus 100 as an embodiment of the liquid concentration measuring apparatus according to the present invention will be described with reference to FIGS. 1 to 6.

  As shown in FIGS. 1 and 2, the moisture concentration measuring device 100 is provided in the positive electrode manufacturing device 10 of a lithium ion secondary battery, and the concentration of moisture contained in the paste 2 applied to one sheet surface 1 a of the aluminum foil 1. It is a device that measures.

The aluminum foil 1 is one of the materials constituting the positive electrode of the lithium ion secondary battery, and is a sheet-like material made of aluminum or an aluminum alloy.
Here, the “sheet-like object” has a pair of sheet surfaces, and either the length and width of the pair of sheet surfaces or the length and width of the pair of sheet surfaces is a pair of sheets. An article having a shape larger than the space (thickness) between the surfaces.

The paste 2 is an embodiment of the measurement object according to the present invention, and contains moisture.
More specifically, the paste 2 includes a positive electrode active material (for example, a lithium transition metal oxide such as lithium cobaltate), an electrolyte (for example, an organic solvent (ethylene carbonate, diethyl carbonate, etc.)) and a lithium salt (lithium hexafluorophosphate). Etc.), and a paste-like material (a mixture of solid and liquid having a certain degree of viscosity).

As shown in FIG. 2, the positive electrode manufacturing apparatus 10 for a lithium ion secondary battery applies the paste 2 to both sheet surfaces of the aluminum foil 1, dries the applied paste 2, rolls it, and then rolls the density ( The positive electrode of the lithium ion secondary battery is manufactured by increasing the (bulk density).
In FIG. 2, for convenience of explanation, a portion of the positive electrode manufacturing apparatus 10 for a lithium ion secondary battery that performs an operation of applying the paste 2 to one sheet surface 1 a of the aluminum foil 1 and drying the applied paste 2. Only the other parts are shown, and the other parts are not shown.

  A positive electrode manufacturing apparatus 10 for a lithium ion secondary battery includes conveying rollers 11 and 12, a paste applying apparatus 13, a heater 14, and the like.

The conveyance rollers 11 and 12 are provided in the middle of the conveyance path of the aluminum foil 1. The conveyance rollers 11 and 12 rotate while contacting the aluminum foil 1 to convey the aluminum foil 1 along the conveyance path while applying a predetermined tension to the aluminum foil 1. The transport roller 11 is located upstream of the transport roller 12 in the transport path.
In the portion of the aluminum foil 1 that is stretched between the conveyance roller 11 and the conveyance roller 12, the sheet surface 1a faces upward.

The paste application device 13 applies the paste 2 to one sheet surface 1 a of the aluminum foil 1.
The paste application device 13 includes a container 13a and a nozzle 13b, and discharges the paste 2 filled in the container 13a from the tip of the nozzle 13b.
The tip of the nozzle 13b is disposed downward at a position facing the upstream portion (portion close to the conveyance roller 11) of the sheet surface 1a of the aluminum foil 1 stretched between the conveyance rollers 11 and 12.
By discharging the paste 2 from the paste coating device 13 while transporting the aluminum foil 1 along the transport path, the paste 2 is evenly applied to the sheet surface 1a of the aluminum foil 1 (so that the thickness of the paste 2 is uniform). ) Applied.

The heater 14 dries the paste 2 applied to the sheet surface 1a of the aluminum foil 1 by heating.
The heater 14 is disposed on the sheet surface 1 a of the aluminum foil 1 stretched between the conveying rollers 11 and 12 so as to face a portion on the downstream side of the paste applying device 13.
The heater 14 is an electric resistance heater, and heats the paste 2 applied to the sheet surface 1 a of the aluminum foil 1 that has moved to a position facing the heater 14. As a result, moisture contained in the paste 2 applied to the sheet surface 1a of the aluminum foil 1 evaporates.

  As shown in FIGS. 1 and 2, the moisture concentration measuring apparatus 100 includes a first light projecting unit 111, a first light receiving unit 112, a second light projecting unit 121, a second light receiving unit 122, a concentration calculating device 130, and an analysis unit 140. Etc.

The first light projecting unit 111 is an embodiment of the first light projecting unit according to the present invention, and projects the laser light 101.
The first light projecting unit 111 includes a light projecting element that generates the laser light 101, a power source that supplies power to the light projecting element, and an optical component (lens) that converges and irradiates the laser light 101 generated by the light projecting element. Etc.).

The first light receiving unit 112 is an embodiment of the first light receiving unit according to the present invention, and receives the laser light 101 projected by the first light projecting unit 111 and detects the intensity of the laser light 101. is there.
The first light receiving unit 112 includes a light receiving element that generates a voltage or current corresponding to the intensity of the received laser light 101, and an optical component (such as a lens) that guides the laser light 101 to the light receiving element.

  As shown in FIGS. 1 and 2, the first light projecting unit 111 and the first light receiving unit 112 are arranged along the transport path of the aluminum foil 1 in the positive electrode manufacturing apparatus 10 for a lithium ion secondary battery. In addition, as shown in FIG. 2, the first light projecting unit 111 and the first light receiving unit 112 are arranged at positions downstream of the heater 14 in the transport path of the aluminum foil 1.

As shown in FIG. 1, the first light projecting unit 111 is on the left side of the left end portion of the aluminum foil 1 as viewed from the upstream side in the transport direction of the aluminum foil 1 transported along the transport path, and the sheet surface of the aluminum foil 1. It arrange | positions in the position which becomes higher than the surface of the paste 2 apply | coated to 1a.
The first light receiving part 112 is a paste 2 applied to the sheet surface 1a of the aluminum foil 1 on the right side of the right end of the aluminum foil 1 as viewed from the upstream side in the transport direction of the aluminum foil 1 transported along the transport path. It arrange | positions in the position which becomes higher than the surface of.
Further, the first light projecting unit 111 and the first light receiving unit 112 are applied to the sheet surface 1a of the aluminum foil 1 in which the direction of the laser light 101 (the optical axis direction of the laser light 101) is transported along the transport path. It arrange | positions so that it may become parallel to the surface of the paste 2. FIG.
Accordingly, the laser light 101 projected from the first light projecting unit 111 and received by the first light receiving unit 112 is the surface of the paste 2 applied to the sheet surface 1a of the aluminum foil 1 that is transported along the transport path. Passes through a position separated by a first measurement distance T1.
Here, the “first measurement distance” refers to the distance between the laser light projected by the first light projecting unit and the measurement surface of the measurement object.

The second light projecting unit 121 is an embodiment of the second light projecting unit according to the present invention, and projects the laser light 102.
The second light projecting unit 121 includes a light projecting element that generates the laser light 102, a power source that supplies power to the light projecting element, and an optical component (lens) that converges and irradiates the laser light 102 generated by the light projecting element. Etc.).

The second light receiving unit 122 is an embodiment of the second light receiving unit according to the present invention, and receives the laser light 102 projected by the second light projecting unit 121.
The second light receiving unit 122 includes a light receiving element that generates a voltage or a current according to the intensity of the received laser light 102 and an optical component (such as a lens) that guides the laser light 102 to the light receiving element.

  As shown in FIGS. 1 and 2, the second light projecting unit 121 and the second light receiving unit 122 are arranged along the transport path of the aluminum foil 1 in the positive electrode manufacturing apparatus 10 for a lithium ion secondary battery. Further, as shown in FIG. 2, the second light projecting unit 121 and the second light receiving unit 122 are disposed at a position downstream of the heater 14 in the conveyance path of the aluminum foil 1.

As shown in FIG. 1, the second light projecting portion 121 is on the left side of the left end portion of the aluminum foil 1 as viewed from the upstream side in the transport direction of the aluminum foil 1 transported along the transport path, and the sheet surface of the aluminum foil 1. It arrange | positions in the position which becomes higher than the surface of the paste 2 apply | coated to 1a. Further, the second light projecting unit 121 is disposed above the first light projecting unit 111.
The second light receiving unit 122 is a paste 2 applied to the sheet surface 1a of the aluminum foil 1 on the right side of the right end of the aluminum foil 1 as viewed from the upstream side in the transport direction of the aluminum foil 1 transported along the transport path. It arrange | positions in the position which becomes higher than the surface of. Further, the second light receiving unit 122 is disposed above the first light receiving unit 112.
The second light projecting unit 121 and the second light receiving unit 122 are arranged so that the direction of the laser beam 102 (the optical axis direction of the laser beam 102) is parallel to the sheet surface 1a of the aluminum foil 1.
Therefore, the laser beam 102 projected from the second light projecting unit 121 and received by the second light receiving unit 122 is the surface of the paste 2 applied to the sheet surface 1a of the aluminum foil 1 that is transported along the transport path. The second measurement distance T2 is larger than the first measurement distance T1 (T2> T1).
Here, the “second measurement distance” refers to the distance between the laser light projected by the second light projecting unit and the measurement surface of the measurement object.

Both the laser beam 101 and the laser beam 102 (in the optical axis direction of the laser beam 101 and the laser beam 102) are parallel to the surface of the paste 2 applied to the sheet surface 1a of the aluminum foil 1 conveyed along the conveyance path. is there.
In addition, as shown in FIG. 2, the laser beam 101 and the laser beam 102 (more precisely, the optical axis direction of the laser beam 101 and the optical axis direction of the laser beam 102) are both aluminum transported along the transport path. It is orthogonal to the conveying direction of the foil 1.
Therefore, the laser beam 101 and the laser beam 102 are parallel to each other.

  As shown in FIG. 2, the virtual plane 103 including the laser beam 101 and the laser beam 102 is orthogonal to the sheet surface 1 a of the aluminum foil 1. In other words, when viewed from the direction perpendicular to the sheet surface 1a of the aluminum foil 1 conveyed along the conveyance path (the direction of arrow A in FIG. 2), the laser beam 101 and the laser beam 102 overlap.

The wavelengths of the laser beam 101 and the laser beam 102 include wavelengths that are absorbed by water.
Therefore, as the number of water molecules on the optical path of the laser beam 101 increases (the concentration of moisture in the atmosphere on the optical path of the laser beam 101 increases), the intensity of the laser beam 101 detected by the first light receiving unit 112 decreases, and the laser The more water molecules are on the optical path of the light 102 (the higher the concentration of moisture in the atmosphere on the optical path of the laser light 102), the lower the intensity of the laser light 102 detected by the second light receiving unit 122.

  Hereinafter, the first measurement distance T1 (the distance between the laser light 101 projected by the first light projecting unit 111 and the surface of the paste 2) and the second measurement distance T2 (light projected by the second light projecting unit 121). A method for setting the distance between the laser beam 102 and the surface of the paste 2 will be described.

The moisture concentration measuring apparatus 100 is an atmosphere containing moisture that evaporates from the paste 2 as a measurement object using the laser light 101 having a relatively short distance from the surface of the paste 2 of the two laser beams 101 and 102. The moisture concentration is detected, the moisture concentration in the atmosphere not containing moisture evaporating from the paste 2 as the measurement object is detected using the laser beam 102 that is relatively far from the surface of the paste 2, and the laser beam 101 is used. By calculating the difference between the moisture concentration (first liquid concentration C1) detected in this way and the moisture concentration (second liquid concentration C2) detected using the laser beam 102, the moisture (paste) originally contained in the atmosphere is calculated. 2), the concentration of moisture evaporating from the paste 2 in the atmosphere is accurately measured, and consequently the concentration of moisture contained in the paste 2 is accurately measured. One in which a constant.
Therefore, in order for the moisture concentration measuring apparatus 100 to accurately measure the concentration of moisture contained in the paste 2, (a) the moisture concentration in the atmosphere on the optical path of the laser beam 101 and the moisture concentration contained in the paste 2 (B) that the concentration of moisture in the atmosphere on the optical path of the laser beam 102 is not affected by moisture evaporating from the paste 2.

The first measurement distance T1 is set based on the boundary layer depth δ of the aluminum foil 1 (more precisely, the paste 2 applied to the aluminum foil 1) conveyed along the conveyance path.
This is because in the region where the distance from the surface of the paste 2 applied to the aluminum foil 1 is less than or equal to the boundary layer depth δ, the atmosphere present in the region follows the surface of the aluminum foil 1 to some extent due to its viscosity. This is because there is a strong correlation between the concentration of moisture contained in the region below the boundary layer depth δ and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1.
The boundary layer depth δ is generally represented by the Reynolds number Re and the width W of the measurement object. However, the boundary layer depth δ is either a laminar flow or a turbulent flow state in the region facing the measurement object. It also changes depending on whether it is in the state.
In addition, it can be determined based on the Reynolds number Re whether the flow state of the atmosphere in the region facing the measurement object is a laminar flow or a turbulent flow.

  The transport speed of the aluminum foil 1 is U, the width of the aluminum foil 1 as viewed from the transport direction of the aluminum foil 1 (more precisely, the width of the paste 2 applied to the aluminum foil 1) is W, and the atmosphere (in this embodiment) In this case, the Reynolds number Re of the aluminum foil 1 transported along the transport path is expressed by the following formula 1, where ρ is the density of the atmosphere) and μ is the viscosity of the atmosphere.

  Whether the flow state of the atmosphere in the region facing the paste 2 applied to the aluminum foil 1 is a laminar flow or a turbulent flow is determined based on the following equations 2 and 3.

When the Reynolds number Re calculated by Expression 1 satisfies the condition of Expression 2, it is determined that the flow state of the atmosphere in the region facing the paste 2 applied to the aluminum foil 1 is a laminar flow.
When the Reynolds number Re calculated by Equation 1 satisfies the condition of Equation 3, it is determined that the flow state of the atmosphere in the region facing the paste 2 applied to the aluminum foil 1 is turbulent.

  When it is determined that the flow state of the atmosphere in the region facing the paste 2 applied to the aluminum foil 1 is a laminar flow, the boundary layer thickness δ is expressed by the following formula 4.

  When it is determined that the flow state of the atmosphere in the region facing the paste 2 applied to the aluminum foil 1 is turbulent, the boundary layer thickness δ is expressed by the following formula 5.

  As shown in Equation 6 below, by setting the first measurement distance T1 to be equal to or less than the boundary layer thickness δ calculated by Equation 4 or Equation 5, the intensity of the laser light 101 detected by the first light receiving unit 112, and consequently The concentration of moisture contained in the atmosphere on the optical path of the laser beam 101 has a strong correlation with the concentration of moisture contained in the paste 2 applied to the aluminum foil 1.

The second measurement distance T2 exists on the optical path of the laser beam 101 when the moisture concentration in the atmosphere existing on the optical path of the laser beam 102 is not evaporated from the paste 2 applied to the aluminum foil 1. A distance that can be considered to be the same as the concentration of moisture in the atmosphere is desirable.
Therefore, the second measurement distance T2 is set to be somewhat larger than the first measurement distance T1, and the moisture evaporated from the paste 2 applied to the aluminum foil 1 does not affect the moisture concentration of the atmosphere on the optical path of the laser beam 102. It is desirable to make it.
As a guideline for the set value of the second measurement distance T2, it is desirable to make the second measurement distance T2 larger than 10 times the boundary layer thickness δ calculated by the expression 4 or 5, as shown in the following expression 7. .

  The density calculation device 130 is connected to the first light receiving unit 112 and acquires the intensity (information related thereto) of the laser light 101 detected by the first light receiving unit 112.

The concentration calculation device 130 functions as a first liquid concentration calculation unit according to the present invention.
That is, the density calculating device 130 is based on the position where the laser light 101 passes based on the intensity of the laser light 101 detected by the first light receiving unit 112 (that is, from the sheet surface 1a of the aluminum foil 1 conveyed along the conveyance path). A first liquid concentration C1 that is a concentration of moisture at a position separated by the first measurement distance T1) is calculated.
More specifically, the concentration calculating device 130 stores the intensity of the laser beam 101 stored in advance and the number of water molecules existing on the optical path of the laser beam 101 (and consequently the concentration of moisture in the atmosphere through which the optical path of the laser beam 101 passes). The first liquid concentration C1 is calculated by substituting the intensity of the laser beam 101 detected by the first light receiving unit 112 into the relational expression.

  The density calculation device 130 is connected to the second light receiving unit 122 and acquires the intensity (information related thereto) of the laser light 102 detected by the second light receiving unit 122.

The concentration calculation device 130 functions as a second liquid concentration calculation unit according to the present invention.
That is, the density calculating device 130 is based on the position where the laser beam 102 has passed based on the intensity of the laser beam 102 detected by the second light receiving unit 122 (that is, from the sheet surface 1a of the aluminum foil 1 conveyed along the conveying path). A second liquid concentration C2 that is a concentration of water at a position separated by the second measurement distance T2) is calculated.
More specifically, the concentration calculating device 130 stores the intensity of the laser beam 102 stored in advance and the number of water molecules existing on the optical path of the laser beam 102 (and consequently the concentration of moisture in the atmosphere through which the optical path of the laser beam 102 passes). The second liquid concentration C2 is calculated by substituting the intensity of the laser beam 101 detected by the second light receiving unit 122 into the relational expression.

As described above, the concentration calculation device 130 is an embodiment of the first liquid concentration calculation unit according to the present invention and an embodiment of the second liquid concentration calculation unit according to the present invention.
In this embodiment, the concentration calculation device 130 has a function as the first liquid concentration calculation unit according to the present invention and a function as the second liquid concentration calculation unit according to the present invention (the first liquid concentration calculation unit and the first liquid concentration calculation unit). However, the present invention is not limited to this, and the first liquid concentration calculation unit and the second liquid concentration calculation unit may be separate.

  In addition, the concentration calculation device 130 according to the present embodiment uses the laser beam detected by the first light receiving unit 112 in the relational expression between the intensity of the laser beam 101 stored in advance and the number of water molecules existing on the optical path of the laser beam 101. The first liquid concentration C1 is calculated by substituting the intensity of the light 101, and the second received light is expressed in the relational expression between the intensity of the laser light 102 stored in advance and the number of water molecules existing on the optical path of the laser light 102. Although the second liquid concentration C2 is calculated by substituting the intensity of the laser beam 102 detected by the unit 122, the present invention is not limited to this.

In other words, the first liquid concentration calculation unit according to the present invention is detected by the data table indicating the relationship between the intensity of the laser beam stored in advance and the number of water molecules existing on the optical path of the laser beam and the first light receiving unit. The first liquid concentration C1 may be calculated by comparing the intensity of the laser light.
Similarly, the second liquid concentration calculation unit according to the present invention is detected by the data table indicating the relationship between the intensity of the laser beam stored in advance and the number of water molecules existing on the optical path of the laser beam and the second light receiving unit. The second liquid concentration C2 may be calculated by comparing the intensity of the emitted laser light.

  The analysis unit 140 is a device that analyzes the first liquid concentration C1 and the second liquid concentration C2 calculated by the concentration calculation device 130. The analysis unit 140 includes an analysis device 141, an input device 142, and a display device 143.

  The analysis device 141 can store various programs such as a correction liquid concentration calculation program and a measurement object liquid concentration calculation program, which will be described later, and can develop these programs. An operation can be performed, and a result of the operation can be stored.

The analysis device 141 may actually have a configuration in which CPUs, ROMs, RAMs, HDDs, and the like are connected to each other by a bus, or may be configured by a one-chip LSI or the like.
The analysis device 141 of the present embodiment is a dedicated product, but can also be achieved by storing the above-described program in a commercially available personal computer or workstation.

  The analysis device 141 is connected to the concentration calculation device 130 and can acquire information on the first liquid concentration C1 and the second liquid concentration C2 calculated by the concentration calculation device 130.

The input device 142 is connected to the analysis device 141, and inputs various information / instructions related to the measurement of the concentration of moisture contained in the paste 2 by the moisture concentration measurement device 100 to the analysis device 141.
The input device 142 of the present embodiment is a dedicated product, but the same effect can be achieved by using, for example, a commercially available keyboard, mouse, pointing device, button, switch, or the like.

The display device 143 displays the input contents from the input device 142 to the analysis device 141, the operation status of the moisture concentration measuring device 100, the measurement result of the concentration of moisture contained in the paste 2, and the like.
Although the display device 143 of this embodiment is a dedicated product, for example, a similar effect can be achieved by using a commercially available liquid crystal display (LCD), a CRT display (Cathode Ray Tube Display), or the like. is there.

Below, the detail of a structure of the analyzer 141 is demonstrated.
The analysis device 141 is an embodiment of the measurement object liquid concentration calculation unit according to the present invention, and is along the transport path based on the first liquid concentration C1 and the second liquid concentration C2 calculated by the concentration calculation device 130. The concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed in this manner is calculated.
Functionally, the analysis device 141 includes a storage unit 141a, a correction liquid concentration calculation unit 141b, and a measurement target liquid concentration calculation unit 141c.

The storage unit 141a stores various parameters (numerical values) used in performing calculations and the like by the analysis device 141, a history of operation states of the moisture concentration measurement device 100, measurement results, and the like.
The storage unit 141a is essentially a memory such as a RAM, a storage medium such as an HDD, a CD-ROM, or a DVD-ROM.

The correction liquid concentration calculator 141b calculates a correction liquid concentration Cr that is a correction value of the first liquid concentration C1.
Substantially, the analysis device 141 performs a predetermined calculation or the like according to the correction liquid concentration calculation program stored in the analysis device 141, thereby functioning as the correction liquid concentration calculation unit 141b.
The correction liquid concentration calculation unit 141b is calculated by the first liquid concentration C1 calculated by the concentration calculation device 130, the optical path length L1 of the laser light 101 projected from the first light projection unit 111, and the concentration calculation device 130. Using the second liquid concentration C2 and the optical path length L2 of the laser light 102 projected from the second light projecting unit 121, the correction liquid concentration Cr is calculated based on the following equation (8).
The calculated value of the correction liquid concentration Cr is appropriately stored in the storage unit 141a.

The first liquid concentration C1 is essentially the sum of the concentration of moisture originally present in the atmosphere on the optical path of the laser beam 101 and the concentration of moisture evaporated from the paste 2.
The correction value Cr is the difference between the first liquid concentration C1 and the second gas concentration C2, and originally exists in the atmosphere from the first liquid concentration C1 (that is, the concentration of moisture contained in the atmosphere on the optical path of the laser beam 101). This excludes the influence of moisture concentration (not derived from paste 2).
Note that by multiplying the second liquid concentration C2 by a coefficient (L1 / L2) in Equation 8, the influence of the difference in optical path length between the laser light 101 and the laser light 102 on the correction value Cr is eliminated.

The measurement object liquid concentration calculation unit 141c has “a relationship between the correction liquid concentration Cr stored in advance and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path” and “ The concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path is calculated by comparing the calculated correction liquid concentration Cr ”.
Substantially, the analysis device 141 performs a predetermined calculation or the like according to the measurement object liquid concentration calculation program stored in the analysis device 141, thereby functioning as the measurement object liquid concentration calculation unit 141c.

The storage unit 141a stores a relational expression representing the relationship between the correction liquid concentration Cr and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 transported along the transport path.
The relationship between the correction liquid concentration Cr and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 transported along the transport path is, for example, the paste applied to the aluminum foil 1 transported along the transport path The water concentration is measured by a drying method at a plurality of locations of 2, and is obtained in advance by performing an experiment for calculating the correction liquid concentration Cr at the corresponding location.

The measurement target liquid concentration calculation unit 141c stores the relationship between the “correction liquid concentration Cr stored in the storage unit 141a and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path. By substituting the correction liquid concentration Cr calculated by the correction liquid concentration calculation unit 141b into the relational expression, the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path is determined. calculate.
The calculated value of the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 (measurement result of the concentration of moisture contained in the paste 2) is appropriately stored in the storage unit 141a.

  Hereinafter, a measurement result when the concentration of moisture contained in the paste 2 is measured using the moisture concentration measuring device 100, and a paste using the moisture concentration measuring device 50 which is an embodiment of a conventional liquid concentration measuring device. 2 is compared with the measurement result when the concentration of water contained in 2 is measured.

The moisture concentration measuring device 50 is a device that measures the concentration of moisture contained in the collected gas (sampling gas).
As shown in FIG. 2, the moisture concentration measuring device 50 includes a gas transport pipe 51, a suction pump 52, a pretreatment device 53, and a measuring device 54.

The gas transport pipe 51 is a pipe that collects and transports a part of the atmosphere of the part facing the paste 2 applied to the aluminum foil 1 transported along the transport path. Both ends of the gas transfer pipe 51 are open, and form an intake port 51a and an exhaust port 51b, respectively.
The intake port 51a of the gas transport pipe 51 is disposed at a position separated from the surface of the paste 2 applied to the aluminum foil 1 transported along the transport path by the first measurement distance T1. The intake port 51 a of the gas transfer pipe 51 is disposed at a position upstream of the laser 101 and downstream of the heater 14 in the transfer direction of the transfer path.
The exhaust port 51 b of the gas transport pipe 51 is disposed at a position away from the transport path of the aluminum foil 1.

  The suction pump 52 is a pump provided in the middle of the gas transport pipe 51. When the suction pump 52 is operated, the atmosphere is sucked as a sampling gas from the suction port 51a of the gas transport pipe 51.

The pretreatment device 53 is a device that performs pretreatment on the sampling gas.
Here, “pretreatment” refers to removal of dust and the like contained in the sampling gas.
The pretreatment device 53 is provided in the middle of the gas transport pipe 51 and downstream of the suction pump 52 in the sampling gas transport direction.

The measuring device 54 is a device that measures the concentration of moisture contained in the sampling gas.
The measurement device 54 is included in the sampling gas based on a container that collects the sampling gas, a sensor that is disposed in the container and generates a signal corresponding to the concentration of moisture contained in the sampling gas, and a signal acquired from the sensor. A calculation device for calculating the concentration of moisture is provided.
The measuring device 54 is provided in the middle of the gas transport pipe 51 and downstream of the pretreatment device 53 in the sampling gas transport direction.

  The sampling gas sucked from the intake port 51 a of the gas transport pipe 51 is discharged from the exhaust port 51 b of the gas transport pipe 51 through the suction pump 52, the pretreatment device 53, and the measuring device 54.

In the following, the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 by the paste application device 13 suddenly rises from the middle, and the paste 2 with the increased concentration of moisture becomes the intake port of the gas transport pipe 51 at time t1. A case will be described in which the beam passes directly below 51a and passes immediately below the laser beam 101 at time t2.
As shown in FIG. 3, in the case of the water concentration measuring apparatus 100, the correction liquid concentration Cr (excluding the influence of the concentration of water originally present in the atmosphere (not derived from the paste 2) from the first liquid concentration C1) The concentration is Ca until t2, and increases rapidly from the point of time t2 to reach concentration Cb.
On the other hand, in the case of the moisture concentration measuring device 50, the measurement result of the moisture concentration of the sampling gas is the concentration Ca until the time t1, and starts to rise after the time t1, but as the case of the moisture concentration measuring device 100, it is more rapid. In this case, the water concentration does not increase, and the concentration Cb is reached after a considerable time.

  Below, the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 by the paste application device 13 and heated by the heater 14 temporarily rises abruptly from the middle, and the paste 2 whose concentration of moisture has increased is time. A case will be described in which the gas passes through the intake port 51a of the gas transport pipe 51 at t3 and passes directly under the laser beam 101 at time t4.

As shown in FIG. 4, in the case of the water concentration measuring apparatus 100, the correction liquid concentration Cr (excluding the influence of the concentration of water originally present in the atmosphere (not derived from the paste 2) from the first liquid concentration C1) The concentration is Ca until t4. The concentration Ca rapidly increases from the time t4 is reached, reaches the concentration Cb, and then decreases rapidly to become the concentration Ca again.
On the other hand, in the case of the moisture concentration measuring device 50, the measurement result of the moisture concentration of the sampling gas is the concentration Ca until the time t3, and starts to rise after the time t3, but is more rapid as in the case of the moisture concentration measuring device 100. However, the water concentration does not increase, and after a considerable time has elapsed, the concentration Cd reaches a concentration Cd lower than the concentration Cb, and then gradually decreases to the concentration Ca again.

As described above, the moisture concentration measuring apparatus 100 can measure the corrected liquid concentration Cr, and thus the concentration of moisture contained in the paste 2, in real time and accurately without causing a response delay. The measuring device 50 causes a response delay and cannot measure the moisture concentration of the sampling gas in real time and with high accuracy.
In the case of the moisture concentration measuring apparatus 100, the intensities of the laser light 101 and the laser light 102 are detected by the first light receiving unit 112 and the second light receiving unit 122, respectively, and information on the intensity of the laser light 101 and the laser light 102 is obtained. Is obtained by the analyzer 141 and the time required for a series of operations in which the correction liquid concentration Cr is calculated by the correction liquid concentration calculation unit 141b is very short (the series of operations are performed instantaneously), while moisture In the case of the concentration measuring device 50, the sampling gas collected at the intake port 51a reaches the measuring device 54, moisture contacts the surface of the sensor of the measuring device 54, and a signal corresponding to the moisture concentration is generated. This is because the time required for a series of operations in which the calculation device of the measurement device 54 calculates the moisture concentration based on the signal is relatively long.
In the case of the moisture concentration measuring device 50, the measurement accuracy is also lowered by mixing gases collected at different times in the sampling gas transport path.

Further, as shown in FIG. 5, when the concentration of moisture contained in the paste 2 is not uniform in the width direction of the aluminum foil 1, and a portion where the concentration of moisture contained in the paste 2 is low and a portion where it is high are mixed, they are opposed. Similarly, a low portion (concentration Ce) and a high portion (concentration Cf) also exist in the atmosphere.
In such a case, in the moisture concentration measuring apparatus 100, since the width direction of the aluminum foil 1 and the optical axis direction of the laser beams 101 and 102 are the same, the peak concentration (Cf) itself in the portion where the moisture concentration is high is detected. However, it is possible to detect the average value Cg of the moisture concentration in the width direction of the aluminum foil 1 as shown in FIG.
On the other hand, in the moisture concentration measuring apparatus 50, as shown in FIG. 5, when the intake port 51a of the gas transport pipe 51 is arranged at a position corresponding to a portion where the concentration of moisture contained in the paste 2 is low, FIG. As shown, the measured value of the moisture concentration remains unchanged as Ce, and the change in the moisture concentration distribution in the width direction of the aluminum foil 1 cannot be detected.

  Thus, the moisture concentration measuring apparatus 100 cannot accurately measure individual peak values of the moisture concentration distribution when the moisture concentration distribution in the width direction of the aluminum foil 1 changes. It is possible to detect a change in moisture concentration in the direction in the form of “change in average value of moisture concentration in the width direction”.

As described above, the moisture concentration measuring apparatus 100 is
A first light projecting unit 111 for projecting a laser beam 101 parallel to the surface of the paste 2 spaced from the surface of the paste 2 containing moisture by a first measurement distance T1;
A first light receiving unit 112 that receives the laser light 101 projected by the first light projecting unit 111 and detects the intensity of the laser light 101;
A second light projecting unit 121 that projects a laser beam 102 parallel to the surface of the paste 2 separated from the surface of the paste 2 by a second measurement distance T2 that is larger than the first measurement distance T1;
A second light receiving unit 122 that receives the laser light 102 projected by the second light projecting unit 121 and detects the intensity of the laser light 102;
Based on the intensity of the laser beam 101 detected by the first light receiving unit 112, the first liquid concentration C1 that is the water concentration at a position separated from the surface of the paste 2 by the first measurement distance T1 is calculated, and the second light receiving unit A concentration calculation device 130 that calculates a second liquid concentration C2 that is a moisture concentration at a position separated from the surface of the paste 2 by a second measurement distance T2 based on the intensity of the laser beam 102 detected by 122;
An analysis device 141 for calculating the concentration of moisture contained in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2 calculated by the concentration calculation device 130;
It comprises.
This configuration has the following advantages.
That is, the moisture concentration measuring apparatus 100 measures the concentration of moisture evaporating from the paste 2 as a measurement object and measures the concentration of moisture contained in the paste 2 based on the moisture concentration. It is possible to accurately measure the concentration of contained water without contact.
In particular, since the moisture concentration measuring apparatus 100 measures the concentration in the atmosphere of moisture evaporating from the paste 2 that is the measurement object in a non-contact manner, the paste 2 that is the measurement object (in this embodiment, strictly speaking, the paste 2 Even when the aluminum foil 1) coated with is moved while maintaining the first measurement distance T1 and the second measurement distance T2, the concentration of moisture contained in the paste 2 can be measured in real time.
Moreover, since the moisture concentration measuring apparatus 100 calculates the concentration of moisture contained in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2, the moisture originally present in the atmosphere (not derived from the paste 2). The measurement accuracy of the concentration of moisture contained in the paste 2 is improved.
Furthermore, since the moisture concentration measuring apparatus 100 calculates the concentration of moisture contained in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2, the optical path lengths of the laser light 101 and the laser light 102 are respectively Even if the laser beam 101 and the laser beam 102 change or pass through a dead space (portions represented by lengths W11, W12, W21, and W22 in FIG. 1), the laser beam 101 and the laser beam It is possible to accurately measure the concentration of moisture contained in the paste 2 by eliminating the influence of moisture present in the portion corresponding to the dead space in the optical path of the light 102.
This means that it is not necessary to arrange the first light projecting unit 111, the first light receiving unit 112, the second light projecting unit 121, and the second light receiving unit 122 at a position facing the surface of the paste 2 as the measurement object. The first light projecting unit 111, the first light receiving unit 112, the second light projecting unit 121, and the second light receiving unit 122 are damaged by the heat from the paste 2 when the paste 2 as the measurement object is at a high temperature. It is possible to prevent the situation.

Further, the wavelength of the laser light 101 projected by the first light projecting unit 111 of the moisture concentration measuring apparatus 100 and the wavelength of the laser light 101 projected by the second light projecting unit 121 are both determined by the moisture contained in the paste 2. Includes wavelengths that are absorbed.
With this configuration, the intensity of the laser beam 101 detected by the first light receiving unit 112 changes according to the concentration of moisture contained in the atmosphere on the optical path of the laser beam 101, and the second light receiving unit 122 Since the intensity of the detected laser beam 102 changes in accordance with the concentration of moisture contained in the atmosphere on the optical path of the laser beam 102, the concentration of moisture contained in the paste 2 can be measured with high accuracy.

The laser light 101 projected by the first light projecting unit 111 of the moisture concentration measuring apparatus 100 and the laser light 102 projected by the second light projecting unit 121 are parallel to each other.
The plane 103 including the laser beam 101 projected by the first projector 111 and the laser beam 102 projected by the second projector 121 is orthogonal to the surface of the paste 2.
With this configuration, both the laser beam 101 and the laser beam 102 face each other at the same position on the surface of the paste 2 (at the same time), and the laser beam 101 detected by the first light receiving unit 112 Based on the portion of the first liquid concentration C1 calculated based on the intensity relating to the moisture originally present in the atmosphere (not derived from the paste 2) and the intensity of the laser beam 102 detected by the second light receiving unit 122. It is possible to regard the calculated second liquid concentration C2 as the same. Therefore, the measurement accuracy of the concentration of moisture contained in the paste 2 is improved.

The first measurement distance T1 of the moisture concentration measuring apparatus 100 is set according to the following procedures (a) to (d).
(A) Using the transport speed U of the paste 2 applied to the aluminum foil 1, the width W of the paste 2 viewed from the transport direction of the paste 2 applied to the aluminum foil 1, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. , Reynolds number Re is calculated based on Equation 1.
(B) When the calculated Reynolds number Re satisfies the relationship expressed by Equation 2, it is determined that the flow state of the region facing the surface of the paste 2 is laminar, and the calculated Reynolds number Re is Equation 3. When the relationship shown is satisfied, it is determined that the flow state of the region facing the surface of the paste 2 is turbulent.
(C) When it is determined that the flow state of the region facing the surface of the paste 2 is a laminar flow, the boundary layer thickness δ is calculated based on Equation 4, and the flow state of the region facing the surface of the paste 2 Is determined to be a turbulent flow, the boundary layer thickness δ is calculated based on Equation 5.
(D) The first measurement distance T1 is set to a range that satisfies the relationship expressed by Equation 6.
With this configuration, the intensity of the laser beam 101 detected by the first light receiving unit 112 and the concentration of moisture contained in the atmosphere on the optical path of the laser beam 101 are included in the paste 2 applied to the aluminum foil 1. Therefore, the measurement accuracy of the concentration of water contained in the paste 2 is improved.

Further, the second measurement distance T2 of the moisture concentration measuring apparatus 100 is set to a range that satisfies the relationship expressed by Equation 7.
With this configuration, it is possible to eliminate the influence of “moisture evaporated from the paste 2” from the second liquid concentration C2 calculated based on the intensity of the laser light 102 detected by the second light receiving unit 122. Thus, the measurement accuracy of the concentration of moisture contained in the paste 2 is improved.

In addition, the analysis device 141 of the moisture concentration measuring device 100 includes:
The first liquid concentration C1 calculated by the concentration calculation device 130, the optical path length L1 of the laser light 101 projected from the first light projecting unit 111, the second liquid concentration C2 and the second liquid concentration C2 calculated by the concentration calculation device 130 Using the optical path length L2 of the laser light 102 projected from the light projecting unit 121, a correction liquid concentration Cr that is a correction value of the first liquid concentration C1 is calculated based on Equation 8.
With this configuration, (α) the optical path length L2 of the laser beam 102 is the same as the optical path length L1 of the laser beam 101, and (β) the optical path length L2 of the laser beam 102 is the laser beam 101. In any of the cases where the optical path length L1 is different from that of the first liquid concentration C1, “the influence of moisture originally present in the atmosphere (not derived from the paste 2)” is accurately excluded from the first liquid concentration C1. Is possible.
Therefore, it is possible to calculate the correction liquid concentration Cr with high accuracy and to measure the concentration of moisture contained in the paste 2 with high accuracy.

In addition, the analysis device 141 of the moisture concentration measuring device 100 includes:
By comparing the “relationship between the correction liquid concentration Cr and the concentration of moisture contained in the paste 2” stored in the storage unit 141a in advance with the “calculated correction liquid concentration Cr”, it is included in the paste 2 Calculate the moisture concentration.
By comprising in this way, it is possible to measure the density | concentration of the water | moisture content contained in the paste 2 accurately and in real time.

  The moisture concentration measuring apparatus 100 according to the present embodiment calculates the correction liquid concentration Cr based on the first liquid concentration C1 and the second liquid concentration C2 calculated by the concentration calculation device 130, and pastes based on the correction liquid concentration Cr. Although the concentration of moisture contained in the paste 2 is measured by calculating the concentration of moisture contained in 2, the present invention is not limited to this.

That is, the present invention calculates and calculates the correction liquid concentration Cr based on the first liquid concentration C1 calculated by the first liquid concentration calculation unit and the second liquid concentration C2 calculated by the second liquid concentration calculation unit. It may be configured to determine whether or not the concentration of moisture contained in the measurement object is within a preset desired range based on the corrected liquid concentration Cr.
More specifically, the measurement object liquid concentration calculation unit according to the present invention may compare the “calculated correction liquid concentration Cr” with the “prestored threshold value”. The threshold value can be set by a method similar to the above-described “relational expression representing the relationship between the correction liquid concentration Cr and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 transported along the transport path”. Is possible.
As an example of a configuration in which the measurement object liquid concentration calculation unit compares the “calculated correction liquid concentration Cr” with the “prestored threshold value”, (1) “calculated correction liquid concentration Cr” Is greater than the “prestored threshold value”, it is determined that the concentration of water contained in the measurement object is in a desired range, and the “calculated correction liquid concentration Cr” is “the prestored threshold value”. In the case where the concentration of water contained in the measurement object is not within the desired range, (2) “calculated correction liquid concentration Cr” is greater than “prestored threshold” Is determined that the concentration of moisture contained in the measurement object is not within the desired range, and is included in the measurement object when the “calculated correction liquid concentration Cr” is smaller than the “prestored threshold value”. A structure that determines that the moisture concentration is within the desired range. , (3) “Calculated correction liquid concentration Cr” is not less than “first threshold value stored in advance” and “second threshold value stored in advance (second threshold value is larger than first threshold value)” If it is below, it is determined that the concentration of water contained in the measurement object is in a desired range, and the “calculated correction liquid concentration Cr” is less than the “first threshold value” or “second threshold value”. If it is too large, a configuration in which the concentration of moisture contained in the measurement object is determined not to be in a desired range can be used.
The configurations (1) to (3) are appropriately selected according to the properties of the measurement object, the application of the present invention, and the like.

Although the moisture concentration measuring apparatus 100 of the present embodiment is configured to measure the concentration of moisture contained in the paste 2 as the measurement object, the present invention is not limited to this, and the concentration of the liquid contained in the measurement object is measured. It is possible to apply to a wide range of uses.
Other examples of the liquid contained in the measurement target include organic solvents and oils.

Hereinafter, an embodiment of the liquid concentration measuring method according to the present invention will be described with reference to FIG.
One embodiment of the liquid concentration measuring method according to the present invention is a method of measuring the concentration of moisture contained in the paste 2 using the moisture concentration measuring apparatus 100, and a laser beam projecting / receiving step as shown in FIG. S1100, first liquid concentration / second liquid concentration calculation step S1200, and measurement object liquid concentration calculation step S1300.

The laser beam projecting / receiving process S1100 is an embodiment of the laser beam projecting / receiving process according to the present invention. The parallel laser beam 101 is projected, the laser beam 101 is received and the intensity of the laser beam 101 is detected, and the paste is separated from the surface of the paste 2 by a second measurement distance T2 larger than the first measurement distance T1. 2 is a step of projecting a laser beam 102 parallel to the surface 2 and receiving the laser beam 102 to detect the intensity of the laser beam 102.
When the laser light projecting / receiving step S1100 is completed, the process proceeds to the first liquid concentration / second liquid concentration calculating step S1200.

The first liquid concentration / second liquid concentration calculation step S1200 is an embodiment of the first liquid concentration / second liquid concentration calculation step according to the present invention, and is separated from the surface of the paste 2 by the first measurement distance T1. Based on the intensity of the emitted and received laser light 101, the first liquid concentration C1 that is the water concentration at a position separated from the surface of the paste 2 by the first measurement distance T1 is calculated, and the first liquid concentration C1 is calculated from the surface of the paste 2. Based on the intensity of the received laser beam 102, the second liquid concentration C2 that is the water concentration at the position separated from the surface of the paste 2 by the second measurement distance T2 is calculated based on the intensity of the received laser beam 102. It is a process.
When the first liquid concentration / second liquid concentration calculating step S1200 is completed, the process proceeds to the measurement target liquid concentration calculating step S1300.

The measurement target liquid concentration calculation step S1300 is an embodiment of the measurement target liquid concentration calculation step according to the present invention, and the first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculation step S1200 and In this step, the concentration of water contained in the paste 2 is calculated based on the second liquid concentration C2.
As shown in FIG. 7, the measurement target liquid concentration calculation step S1300 includes a correction liquid concentration calculation step S1310 and a concentration calculation step S1320.

In the correction liquid concentration calculation step S1310, the first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculation step S1200, the optical path length L1 of the laser beam 101, the first liquid concentration / second liquid concentration calculation step S1200. This is a step of calculating the correction liquid concentration Cr based on Equation 8 using the second liquid concentration C2 calculated in step S2 and the optical path length L2 of the laser beam 102.
When the correction liquid concentration calculation step S1310 ends, the process proceeds to the concentration calculation step S1320.

The concentration calculation step S1320 includes “a relationship between the correction liquid concentration Cr stored in advance and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path” and “correction liquid concentration calculation. In this step, the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path is calculated by comparing the corrected liquid concentration Cr calculated in step S1310.
More specifically, in the concentration calculation step S1320, “relationship between“ corrected liquid concentration Cr stored in advance and the concentration of moisture contained in the paste 2 applied to the aluminum foil 1 transported along the transport path ”. By substituting the correction liquid concentration Cr calculated in the correction liquid concentration calculation step S1310 into the formula, the concentration of water contained in the paste 2 applied to the aluminum foil 1 conveyed along the conveyance path is calculated. The

As described above, an embodiment of the liquid concentration measuring method according to the present invention is as follows.
The laser beam 101 is projected from the surface of the paste 2 containing moisture at a first measurement distance T1 and parallel to the surface of the paste 2, the laser beam 101 is received, the intensity of the laser beam 101 is detected, and the paste The laser beam 102 is projected from the surface 2 by a second measurement distance T2 larger than the first measurement distance T1 and parallel to the surface of the paste 2, the laser beam 102 is received, and the intensity of the laser beam 102 is detected. Laser light projecting / receiving step S1100,
The first is the moisture concentration at a position spaced from the surface of the paste 2 by the first measurement distance T1 and projected from the surface of the paste 2 by the first measurement distance T1 based on the intensity of the received laser beam 101. While calculating the liquid concentration C1, the light was projected away from the surface of the paste 2 by the second measurement distance T2, and was separated from the surface of the paste 2 by the second measurement distance T2 based on the intensity of the received laser beam 102. A first liquid concentration / second liquid concentration calculating step S1200 for calculating a second liquid concentration C2 which is a moisture concentration at the position;
A measurement object liquid concentration calculation step S1300 for calculating a concentration of water contained in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2 calculated in the first liquid concentration / second liquid concentration calculation step S1200; ,
It comprises.
This configuration has the following advantages.
That is, in one embodiment of the liquid concentration measuring method according to the present invention, the concentration of moisture evaporating from the paste 2 as the measurement object is measured, and the concentration of moisture contained in the paste 2 is based on the moisture concentration. Therefore, it is possible to accurately measure the concentration of water contained in the paste 2 without contact.
In particular, one embodiment of the liquid concentration measuring method according to the present invention measures the concentration of moisture evaporating from the paste 2 as the measurement object in a non-contact manner, so that the paste 2 as the measurement object (this example) In this case, strictly speaking, the concentration of moisture contained in the paste 2 is measured in real time even when the aluminum foil 1) coated with the paste 2 moves while maintaining the first measurement distance T1 and the second measurement distance T2. It is possible.
Moreover, since one Embodiment of the liquid concentration measuring method which concerns on this invention calculates the density | concentration of the water | moisture content contained in the paste 2 based on 1st liquid concentration C1 and 2nd liquid concentration C2, it originally exists in atmosphere. It is possible to eliminate the influence of moisture (not derived from paste 2), and the measurement accuracy of the concentration of moisture contained in paste 2 is improved.
Furthermore, one embodiment of the liquid concentration measuring method according to the present invention calculates the concentration of water contained in the paste 2 based on the first liquid concentration C1 and the second liquid concentration C2. This is a case where the optical path length of the light 102 changes or the laser light 101 and the laser light 102 pass through a dead space (portions represented by lengths W11, W12, W21, and W22 in FIG. 1). However, it is possible to accurately measure the concentration of moisture contained in the paste 2 by eliminating the influence of moisture present in the portion corresponding to the dead space in the optical paths of the laser beam 101 and the laser beam 102.
This means that a device for projecting laser light 101 (first light projecting unit 111 in the case of the present embodiment), a device for receiving laser light 101 (first light receiving unit 112 in the present embodiment), a laser light The surface of the paste 2 serving as a measurement object is a device that projects 102 (second light projecting unit 121 in the case of the present embodiment) and a device that receives laser light 102 (second light receiving unit 122 in the present embodiment). It is necessary to dispose these devices (the first light projecting unit 111 and the first light receiving unit 112) by the heat from the paste 2 when the paste 2 as the measurement object is at a high temperature. It is possible to prevent the second light projecting unit 121 and the second light receiving unit 122) from being damaged.

In one embodiment of the liquid concentration measurement method according to the present invention,
The wavelengths of the laser beam 101 projected at a first measurement distance T1 from the surface of the paste 2 and the laser beam 102 projected at a second measurement distance T2 from the surface of the paste 2 are both paste. 2 includes the wavelength absorbed by the moisture contained in 2.
With this configuration, the intensity of the laser beam 101 detected in the laser beam projecting / receiving step S1100 changes according to the concentration of moisture contained in the atmosphere on the optical path of the laser beam 101 and the laser beam projecting. Since the intensity of the laser beam 102 detected in the light / light receiving step S1100 varies depending on the moisture concentration contained in the atmosphere on the optical path of the laser beam 102, the moisture concentration contained in the paste 2 is accurately measured. It is possible.

In one embodiment of the liquid concentration measurement method according to the present invention,
The laser beam 101 projected at a first measurement distance T1 from the surface of the paste 2 and the laser beam 102 projected at a second measurement distance T2 from the surface of the paste 2 are parallel to each other,
The plane 103 including the laser beam 101 projected at a first measurement distance T1 from the surface of the paste 2 and the laser beam 102 projected at a second measurement distance T2 from the surface of the paste 2 is the paste 2 Orthogonal to the surface of
With this configuration, both the laser beam 101 and the laser beam 102 face each other at the same position (at the same time) on the surface of the paste 2, and are calculated based on the intensity of the received laser beam 101. Of the first liquid concentration C1 that is originally present in the atmosphere (not derived from the paste 2) and the second liquid concentration C2 calculated based on the intensity of the received laser beam 102 is the same. Can be considered. Therefore, the measurement accuracy of the concentration of moisture contained in the paste 2 is improved.

Further, the first measurement distance T1 in the embodiment of the liquid concentration measurement method according to the present invention is set according to the following procedures (a) to (d).
(A) Using the transport speed U of the paste 2 applied to the aluminum foil 1, the width W of the paste 2 viewed from the transport direction of the paste 2 applied to the aluminum foil 1, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. , Reynolds number Re is calculated based on Equation 1.
(B) When the calculated Reynolds number Re satisfies the relationship expressed by Equation 2, it is determined that the flow state of the region facing the surface of the paste 2 is laminar, and the calculated Reynolds number Re is Equation 3. When the relationship shown is satisfied, it is determined that the flow state of the region facing the surface of the paste 2 is turbulent.
(C) When it is determined that the flow state of the region facing the surface of the paste 2 is a laminar flow, the boundary layer thickness δ is calculated based on Equation 4, and the flow state of the region facing the surface of the paste 2 Is determined to be a turbulent flow, the boundary layer thickness δ is calculated based on Equation 5.
(D) The first measurement distance T1 is set to a range that satisfies the relationship expressed by Equation 6.
By configuring in this way, the intensity of the laser beam 101 detected in the laser beam projecting / receiving step S1100, and thus the concentration of moisture contained in the atmosphere on the optical path of the laser beam 101, is applied to the aluminum foil 1. 2 has a strong correlation with the concentration of moisture contained in 2, so that the measurement accuracy of the concentration of moisture contained in paste 2 is improved.

In addition, the second measurement distance T2 in the embodiment of the liquid concentration measurement method according to the present invention is set to a range that satisfies the relationship expressed by Equation 7.
With this configuration, it is possible to eliminate the influence of “moisture evaporated from the paste 2” from the second liquid concentration C2 calculated based on the intensity of the received laser beam 102. The measurement accuracy of the concentration of contained water is improved.

An embodiment of the liquid concentration measuring method according to the present invention is as follows:
In the measurement object liquid concentration calculation step S1300,
The first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculating step S1200, the optical path length L1 of the laser light 101 projected at a first measurement distance T1 from the surface of the paste 2, and the first Using the second liquid concentration C2 calculated in the one liquid concentration / second liquid concentration calculating step S1200 and the optical path length L2 of the laser light 102 projected at a second measurement distance T2 from the surface of the paste 2 Based on Equation 8, a correction liquid concentration Cr that is a correction value of the first liquid concentration C1 is calculated.
With this configuration, (α) the optical path length L2 of the laser beam 102 is the same as the optical path length L1 of the laser beam 101, and (β) the optical path length L2 of the laser beam 102 is the laser beam 101. In any of the cases where the optical path length L1 is different from that of the first liquid concentration C1, “the influence of moisture originally present in the atmosphere (not derived from the paste 2)” is accurately excluded from the first liquid concentration C1. Is possible.
Therefore, it is possible to calculate the correction liquid concentration Cr with high accuracy and to measure the concentration of moisture contained in the paste 2 with high accuracy.

An embodiment of the liquid concentration measuring method according to the present invention is as follows:
In the measurement object liquid concentration calculation step S1300,
By comparing the relationship between the correction liquid concentration Cr stored in advance and the concentration of moisture contained in the paste 2 and the calculated correction liquid concentration Cr, the concentration of moisture contained in the paste 2 is calculated.
By comprising in this way, it is possible to measure the density | concentration of the water | moisture content contained in the paste 2 accurately and in real time.

  One embodiment of the liquid concentration measuring method according to the present invention is a correction liquid concentration Cr based on the first liquid concentration C1 and the second liquid concentration C2 calculated in the first liquid concentration / second liquid concentration calculating step S1200. Is calculated, and the concentration of moisture contained in the paste 2 is measured by calculating the concentration of moisture contained in the paste 2 based on the corrected liquid concentration Cr. However, the present invention is not limited to this.

  That is, the present invention sets the correction liquid concentration Cr based on the first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculation step and the second liquid concentration C2 calculated by the second liquid concentration calculation unit. It may be configured to calculate and determine whether or not the concentration of moisture contained in the measurement object is within a desired range set in advance based on the calculated corrected liquid concentration Cr.

The front view which shows one Embodiment of the liquid concentration measuring apparatus which concerns on this invention. The side view which similarly shows one Embodiment of the liquid concentration measuring apparatus which concerns on this invention. The figure which shows the measurement result of the moisture concentration in the atmosphere in the surface vicinity of the measuring object by one Embodiment of the liquid concentration measuring apparatus which concerns on this invention, and one Embodiment of the conventional liquid concentration measuring apparatus. The figure which similarly shows the measurement result of the moisture concentration in the atmosphere in the surface vicinity of the measurement object by one Embodiment of the liquid concentration measuring apparatus which concerns on invention, and one Embodiment of the conventional liquid concentration measuring apparatus. The figure which shows the relationship between distribution of the moisture concentration in the width direction of a measuring object, and the optical axis direction of the laser beam in one Embodiment of the liquid concentration measuring apparatus which concerns on this invention. The figure which shows the influence which distribution of the water concentration of the width direction of a measurement object has on the measurement result of the water concentration by one Embodiment of the liquid concentration measuring apparatus which concerns on this invention. The flowchart which shows one Embodiment of the liquid concentration measuring method which concerns on this invention.

Explanation of symbols

1 Aluminum foil 2 Paste (measurement object)
100 Moisture concentration measuring device (liquid concentration measuring device)
DESCRIPTION OF SYMBOLS 101 Laser light 102 Laser light 111 1st light projection part 112 1st light-receiving part 121 2nd light projection part 122 2nd light-receiving part 130 Concentration calculation apparatus (1st liquid concentration calculation part, 2nd liquid concentration calculation part)
141 Analyzer (Measurement Object Liquid Concentration Calculation Unit)

Claims (16)

A first light projecting unit that projects laser light that is spaced apart from the measurement surface of the measurement object including the liquid by a first measurement distance and parallel to the measurement surface;
A first light receiving unit that receives the laser light projected by the first light projecting unit and detects the intensity of the laser light;
A second light projecting unit that projects a laser beam parallel to the measurement surface separated from the measurement surface of the measurement object by a second measurement distance greater than the first measurement distance;
A second light receiving unit that receives the laser light projected by the second light projecting unit and detects the intensity of the laser light;
A first liquid concentration calculation unit that calculates a first liquid concentration that is a liquid concentration at a position separated from the measurement surface of the measurement object by a first measurement distance based on the intensity of the laser light detected by the first light receiving unit. When,
A second liquid concentration calculation unit that calculates a second liquid concentration that is a liquid concentration at a position separated from the measurement surface of the measurement object by a second measurement distance based on the intensity of the laser light detected by the second light receiving unit. When,
A measurement object that calculates the concentration of the liquid contained in the measurement object based on the first liquid concentration calculated by the first liquid concentration calculation unit and the second liquid concentration calculated by the second liquid concentration calculation unit. A liquid concentration calculator,
A liquid concentration measuring apparatus comprising:   The liquid concentration measuring device according to claim 1, wherein the wavelengths of the laser beams projected by the first light projecting unit and the second light projecting unit include wavelengths that are absorbed by the liquid contained in the measurement object. . The laser light projected by the first light projecting unit and the laser light projected by the second light projecting unit are parallel to each other,
The plane including the laser light projected by the first light projecting unit and the laser light projected by the second light projecting unit is orthogonal to the measurement surface of the measurement object. The liquid concentration measuring apparatus according to 1. 4. The liquid concentration measurement apparatus according to claim 1, wherein the first measurement distance T <b> 1 is set according to the following procedures (a) to (d).
(A) Based on the following Equation 1, using the conveyance speed U of the measurement object, the width W of the measurement object viewed from the conveyance direction of the measurement object, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. To calculate the Reynolds number Re.
(B) When the calculated Reynolds number Re satisfies the relationship represented by the following formula 2, it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, and the calculated Reynolds number When Re satisfies the relationship expressed by the following equation (3), it is determined that the flow state of the region facing the measurement surface of the measurement object is turbulent.
(C) When it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, the boundary layer thickness δ is calculated based on the following Equation 4 to measure the measurement object: When it is determined that the flow state of the region facing the surface is turbulent, the boundary layer thickness δ is calculated based on the following Equation 5.
(D) Said 1st measurement distance T1 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 6.

The liquid concentration measurement apparatus according to claim 4, wherein the second measurement distance T <b> 2 is set in a range that satisfies a relationship represented by the following Expression 7.

The measurement object liquid concentration calculation unit includes:
The first liquid concentration C1 calculated by the first liquid concentration calculator, the optical path length L1 of the laser light projected from the first light projector, and the second liquid calculated by the second liquid concentration calculator Using the density C2 and the optical path length L2 of the laser light projected from the second light projecting unit, the correction liquid density Cr that is the correction value of the first liquid density C1 is calculated based on the following formula 8. The liquid concentration measuring device according to any one of claims 1 to 5.

The measurement object liquid concentration calculation unit includes:
By comparing the relationship between the correction liquid concentration Cr stored in advance and the concentration of the liquid contained in the measurement object with the calculated correction liquid concentration Cr, the concentration of the liquid contained in the measurement object is determined. The liquid concentration measuring apparatus according to claim 6 to calculate. The measurement object liquid concentration calculation unit includes:
The determination as to whether or not the concentration of the liquid contained in the measurement object is within a preset desired range by comparing the calculated corrected liquid concentration Cr with a threshold value stored in advance. Liquid concentration measuring device. A laser beam that is spaced from the measurement surface of the measurement object including the liquid by a first measurement distance and is parallel to the measurement surface is projected, the laser beam is received to detect the intensity of the laser beam, and the measurement A laser beam that is spaced apart from the measurement surface of the object by a second measurement distance greater than the first measurement distance and is parallel to the measurement surface is projected, the laser beam is received, and the intensity of the laser beam is detected. Laser light projecting / receiving process,
The liquid concentration is projected at a first measurement distance from the measurement surface of the measurement object, and the liquid concentration at a position away from the measurement surface of the measurement object by the first measurement distance is based on the intensity of the received laser beam. While calculating a certain first liquid concentration, the second liquid is projected from the measurement surface of the measurement object by a second measurement distance, and the second liquid is measured from the measurement surface of the measurement object based on the intensity of the received laser beam. A first liquid concentration / second liquid concentration calculating step of calculating a second liquid concentration that is a liquid concentration at a position separated by a measurement distance;
A measurement object liquid concentration calculation step of calculating a concentration of a liquid contained in the measurement object based on the first liquid concentration and the second liquid concentration calculated in the first liquid concentration / second liquid concentration calculation step;
A liquid concentration measuring method comprising:   The wavelength of the laser beam projected at a first measurement distance from the measurement surface of the measurement object and the wavelength of the laser light projected at a second measurement distance from the measurement surface of the measurement object are either The liquid concentration measurement method according to claim 9, which also includes a wavelength absorbed by the liquid contained in the measurement object. A laser beam projected at a first measurement distance from the measurement surface of the measurement object and a laser beam projected at a second measurement distance from the measurement surface of the measurement object are parallel to each other. Yes,
A plane including laser light projected at a first measurement distance away from the measurement surface of the measurement object and a laser light projected at a second measurement distance away from the measurement surface of the measurement object is the plane The liquid concentration measurement method according to claim 9 or 10, wherein the liquid concentration measurement method is orthogonal to the measurement surface of the measurement object. The liquid concentration measurement method according to any one of claims 9 to 11, wherein the first measurement distance T1 is set according to the following procedures (a) to (d).
(A) Based on the following Equation 1, using the conveyance speed U of the measurement object, the width W of the measurement object viewed from the conveyance direction of the measurement object, the density ρ of the atmosphere, and the viscosity μ of the atmosphere. To calculate the Reynolds number Re.
(B) When the calculated Reynolds number Re satisfies the relationship represented by the following formula 2, it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, and the calculated Reynolds number When Re satisfies the relationship expressed by the following equation (3), it is determined that the flow state of the region facing the measurement surface of the measurement object is turbulent.
(C) When it is determined that the flow state of the region facing the measurement surface of the measurement object is a laminar flow, the boundary layer thickness δ is calculated based on the following Equation 4 to measure the measurement object: When it is determined that the flow state of the region facing the surface is turbulent, the boundary layer thickness δ is calculated based on the following Equation 5.
(D) Said 1st measurement distance T1 is set to the range which satisfy | fills the relationship shown by the following Numerical formula 6.

13. The liquid concentration measurement method according to claim 12, wherein the second measurement distance T2 is set in a range that satisfies a relationship represented by the following formula 7.

In the measurement object liquid concentration calculation step,
The first liquid concentration C1 calculated in the first liquid concentration / second liquid concentration calculating step, the optical path length L1 of the laser light projected at a first measurement distance from the measurement surface of the measurement object, The second liquid concentration C2 calculated in the first liquid concentration / second liquid concentration calculating step and the optical path length L2 of the laser beam projected at a second measurement distance from the measurement surface of the measurement object are set. The liquid concentration measurement method according to any one of claims 9 to 13, wherein a correction liquid concentration Cr that is a correction value of the first liquid concentration C1 is calculated based on the following formula 8.

In the measurement object liquid concentration calculation step,
By comparing the relationship between the correction liquid concentration Cr stored in advance and the concentration of the liquid contained in the measurement object with the calculated correction liquid concentration Cr, the concentration of the liquid contained in the measurement object is determined. The liquid concentration measuring method according to claim 14, wherein the liquid concentration is calculated. In the measurement object liquid concentration calculation step,
The determination as to whether the concentration of the liquid contained in the measurement object is within a preset desired range by comparing the calculated corrected liquid concentration Cr with a threshold value stored in advance. Liquid concentration measurement method.

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