JP2012047734A - Spray pressure measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spray pressure measuring apparatus for precisely measuring a jet state of spray without being damaged.SOLUTION: A second spring member 270 to be a plate spring of smaller spring constant than a first spring member 260 is provided in the center in the longitudinal direction of the first spring member 260 to be a plate spring for holding an optical fiber 250 in the state that it elastically deforms as a pressure transmission part 222 is displaced. Even in the environment where pressure is very weak and electromagnetic wave noise occurs, the weak pressure can be measured precisely. Even in situations where excessive pressure is given and the pressure transmission part 222 is considerably displaced, the second spring member 270 is elastically deformed and the first spring member 260 for holding the optical fiber 250 has a relatively small elastic deformation amount. It is prevented that a large ultimate tensile strength radically operates on the optical fiber 250 and that the optical fiber 250 is damaged by the breaking or the like.

Description

  The present invention relates to a spray pressure measuring device for measuring a spray pressure of a spray that sprays and disperses a liquid or two fluids in which a liquid and a gas are mixed.

For example, in a continuous casting process or a steel sheet cooling process, etc., a spray that sprays a liquid such as water as a refrigerant, or a spray that sprays two fluids mixed with a liquid such as water and compressed air as a refrigerant. Cooling devices are widely used. In the continuous casting process or the steel plate cooling process, uneven cooling occurs due to refrigerant pressure fluctuation, spray nozzle clogging (hereinafter referred to as nozzle clogging), and the like.
In particular, in the continuous casting process, cooling unevenness due to nozzle clogging causes solidification delay due to local lack of cooling, and internal cracking occurs due to bulging (swell due to molten steel static pressure) due to a decrease in solidified shell strength. May cause. If the casting speed is lowered to suppress such internal cracks, there is a disadvantage that the production capacity is lowered. When internal cracks are severe, breakout (molten steel outflow due to fracture of the solidified shell) is caused, and it may take a long time to recover, leading to a decrease in production capacity.
Further, in the cooling process of the steel sheet, the difference in cooling rate due to the cooling unevenness causes variations in the strength of the steel sheet and causes the yield to decrease. In addition, due to the difference in cooling rate, warpage of the steel sheet occurs due to the temperature difference between the upper and lower surfaces, and the trouble that the steel sheet collides with the structural member in the spray cooling device occurs, forcing the production line to stop and producing There is also a risk that the ability will decrease.
In order to solve the problem of insufficient cooling due to the clogging of the spray nozzles, various methods for detecting the clogging of the spray are known.

For example, a method is known in which a pressure sensor is mounted on a moving device such as a dummy bar in continuous casting, and the pressure distribution of the spray is measured while moving the moving device (see, for example, Patent Documents 1 and 2).
Also, a method is known in which a piezoelectric element vibration detector is mounted on a dummy bar and the spraying pressure of the spray is measured as the dummy bar moves (see, for example, Patent Document 3).
Further, a piezoelectric element is mounted on a dummy bar or a measurement carriage to measure the spraying pressure of the spray (see, for example, Patent Document 4), and a sheet-like pressure sensitive element is mounted on the measurement carriage such as a dummy bar to spray the spraying pressure. Is known (for example, see Patent Document 5).

However, what detects the blockage of the above-mentioned spray is an electromagnetic wave generated from a configuration using an electric device of a motor used in a continuous casting machine, a spray cooling device or the like in order to detect the presence or absence of the blockage based on the detected electrical signal. Noise affects the detected electrical signal. In particular, the noise level of the electromagnetic noise fluctuates depending on the operating state of the electric device that generates the electromagnetic noise, which causes a disadvantage that the strength of the detected electric signal also fluctuates. For this reason, there is a possibility that inconvenience that it is not possible to determine whether the measurement value has changed due to the influence of electromagnetic noise or the sprayed state of the spray is abnormal.
In fact, as a result of conducting a laboratory experiment by the inventors, a good correlation can be obtained between the change of the cooling condition and the pressure sensor. However, in continuous casting machines and spray coolers, the output based on the electrical signal of the pressure sensor changes greatly due to the effects of electromagnetic noise, and the output reproducibility cannot be obtained even if the cooling conditions are set constant. As a result, the spraying state could not be properly evaluated.

On the other hand, pressure sensors using fiber Bragg gratings (hereinafter referred to as FBG (Fiber Bragg Gratings)) are known as sensors that are not affected by electromagnetic noise.
For example, a configuration is known in which an optical fiber is installed by positioning an FBG on a diaphragm that is displaced by receiving a force (for example, Patent Documents 6 to 8).
Moreover, the structure which fixes the both ends of FBG of an optical fiber to the concrete wall to which tension | tensile_strength is applied and the force of earth and sand is detected, and the deformation | transformation by the earth pressure of a concrete wall is detected (for example, patent document 9).
Furthermore, a configuration is known in which pressure is detected by applying tension to both ends of an FBG of an optical fiber by bellows that expands and contracts due to water pressure or the like (for example, Patent Documents 10 and 11).
In addition, both ends of the four links are connected to each other in a quadrangle so as to be rotatable, and an optical fiber having an FBG is stretched between a pair of diagonally connected parts. A configuration using a link mechanism to which pressure is applied is known (for example, Patent Document 12).
Furthermore, a configuration of a water level gauge is known that detects the water pressure by providing an optical fiber with an FBG that bridges the Bourdon tube to which water pressure is applied, and tension is applied to the optical fiber in response to the expansion of the Bourdon tube according to the water pressure. (For example, Patent Document 13).

Japanese Patent Laid-Open No. 50-97379 Japanese Patent Laid-Open No. 5-177323 Japanese Examined Patent Publication No. 62-3018 Japanese Patent Laid-Open No. 5-92246 JP-A-7-227614 JP 2000-221085 A JP 2001-108553 A JP 2002-98604 A JP 2003-279327 A JP 2007-333621 A JP 2008-209250 A JP 2000-28456 A JP 2001-91334 A

It is conceivable to prevent the influence of electromagnetic noise by using a pressure sensor using FBG as a conventional technique for detecting the spraying state in the above-described continuous casting process or steel plate cooling process.
However, the pressure to be measured is weak, and it is difficult to provide a structure that prevents the FBG from being broken when an excessive pressure is applied while measuring a fine pressure with high sensitivity.
In particular, in the configuration using the link mechanism described in Patent Document 12, for example, a configuration capable of measuring a minute pressure is disclosed, but there is no configuration for protecting the FBG when an excessive pressure is applied. . For this reason, it cannot utilize as a structure which detects the spraying state in the continuous casting process or the cooling process of a steel plate.

That is, in the continuous casting process or the cooling process of the steel sheet, the metallic material except for the part supported by the conveying roll in the conveying direction of the metallic material in order to ensure the uniformity of cooling and improve the cooling efficiency, Designed to be covered with cooling water from spray.
Furthermore, there are various restrictions as described below. For example, sprays have a limited spray spread angle. The rolls in the continuous casting process and the steel sheet cooling process are designed to have a diameter that takes into account factors such as the weight and moving speed of the metal material and the pressure of the molten steel in the case of continuous casting. For this reason, it is necessary to design the outer diameter dimension to a certain level or more from the viewpoint of the strength of the roll. Therefore, there is a restriction that a spray nozzle must be arranged between the rolls so that the rolls and the sprayed cooling water do not interfere with each other. Therefore, the spray nozzles are arranged at regular intervals due to restrictions on the arrangement of the rolls. For example, in a continuous casting machine, the diameter of the roll is about 150 mm to 400 mm, and it is necessary to secure a roll gap of about 40 mm to 50 mm for disposing the spray nozzle. For this reason, the nozzle pitch is about 190 mm to 450 mm. And since there is a limit to the spray spread angle of the spray, in order to prevent the cooling water sprayed with the roll diameter mentioned above from interfering with the roll, the distance from the cooling surface of the metal material to the nozzle is set to It is necessary to be about the radius of. Therefore, in the example of the continuous casting process, the distance between the cooling surface of the metal material and the nozzle is 75 mm to 200 mm.

When the pressure of the cooling water that collides with the cooling surface of the metal material at such a distance is measured, it becomes a low pressure of about 0.1 kPa to 3 kPa, although it varies depending on conditions such as the shape of the nozzle and the amount of water. When such a low pressure is accurately detected by the FBG, it is difficult to provide a structure that prevents damage such as disconnection of the optical fiber when excessive pressure is applied due to changes in the sprayed water flow. It is.
Thus, it is difficult to accurately diagnose the soundness of the spray state resulting from the blockage of the spray without damaging it. For this reason, conventionally, in a continuous casting process or a cooling process of a steel plate, an operator visually inspects and closes hundreds of spray nozzles by using periodic repairs or between castings or through plates. It is necessary to perform complicated work to replace the nozzle. Thus, the inspection requires a great amount of time and troublesome work, and an improvement in productivity reduction is desired.

  An object of this invention is to provide the spray pressure measuring apparatus which can measure the spraying state of a spray accurately, without being damaged in view of such a point.

The spray pressure measuring device of the present invention is a spray pressure measuring device that measures the spray pressure of a spray that sprays and disperses two fluids, or a mixture of two fluids, a liquid and a gas, and is provided in the housing, A pressure receiving portion that is displaced according to the spraying pressure of the spray, an optical fiber having a fiber Bragg grating disposed in the housing, the optical fiber is held in the housing, and the optical fiber is strained by elastic deformation. A first spring member that is provided, and is provided in the first spring member, is formed to have a smaller spring constant than the first spring member, and is elastically deformed in response to the displacement of the pressure receiving portion to elastically deform the first spring member. And a second spring member to be provided.
In the present invention, when the liquid jetted and dispersed from the spray or the two fluids mixed with the liquid and the gas hits the pressure receiving part, the pressure receiving part is displaced. Corresponding to the displacement of the pressure receiving portion, the first spring member that holds the optical fiber having the fiber Bragg grating and acts on the strain is formed, and the spring constant is smaller than that of the first spring member provided on the first spring member. The second spring member is elastically deformed. That is, the second spring member is elastically deformed with a larger elastic deformation amount than the first spring member. The pressure receiving part that has received the spray pressure of the spray is displaced while elastically deforming the first spring member and the second spring member corresponding to the spray pressure, so that the strain corresponding to the spray pressure on the optical fiber, that is, tensile force or compressive force. Act. For this reason, the light diffraction state in the fiber Bragg grating changes, and the ejection pressure is detected.
Even in the situation where the pressure receiving part is greatly displaced due to excessive pressure, the second spring member is greatly elastically deformed, and the first spring member holding the optical fiber has a relatively small amount of elastic deformation. Tensile force or compressive force can be prevented from acting, and damage such as disconnection of the optical fiber can be prevented.

And in this invention, said 1st spring member is a leaf | plate spring which has a center part which opposes the said fiber Bragg grating, and a pair of holding | maintenance part connected with this center part and hold | maintaining the both ends of the said optical fiber, respectively. The second spring member is preferably a leaf spring provided at the center of the first spring member.
In the present invention, the second spring member of the leaf spring is elastically deformed according to the displacement of the pressure receiving portion, and the first spring member of the leaf spring provided with the second spring member at the central portion is also elastically deformed. Due to the elastic deformation of the first spring member, both ends are held by the pair of holding portions of the first spring member in a state where the fiber Bragg grating faces the center portion, and the optical fiber stretched in an arcuate shape is strained, i.e., tensile. Force is applied.
For this reason, a configuration capable of measuring with high accuracy without being affected by electromagnetic noise even in an environment where electromagnetic noise is generated, and preventing damage to the optical fiber even when excessive pressure is applied to the pressure receiving portion, is the center of the first spring member of the leaf spring. The second spring member of the leaf spring is provided with a simple structure and can be easily manufactured.

Moreover, in this invention, it is preferable to set it as the structure equipped with the leaf | plate spring-shaped base part which has the intermediate part attached in the said housing | casing, and the edge part to which the holding part of said 1st spring member is each attached.
In this invention, the holding | maintenance part of a 1st spring member is each attached to the edge part of the leaf | plate spring-shaped base part by which the intermediate part was attached and fixed in the housing | casing. Thus, the first spring member and the pedestal portion constitute a link mechanism that is elastically deformed corresponding to the elastic deformation of the second spring member, and that strains the optical fiber, that is, applies a tensile force.
For this reason, a configuration that can accurately measure even in an environment where electromagnetic noise is generated without being affected by the electromagnetic noise, and that can prevent damage to the optical fiber even when excessive pressure is applied to the pressure receiving portion constitutes a link mechanism using a leaf spring. It is obtained with a simple structure and can be easily manufactured. Furthermore, since the link mechanism is configured, it is possible to accurately measure even a minute pressure of, for example, about 0.1 kPa to 3 kPa.

In the present invention, the first spring member is a leaf spring having a central portion and a holding portion connected to the central portion and holding the optical fiber, and the second spring member is the first spring member. It is preferable to set it as the structure which is a leaf | plate spring provided in the center part.
In the present invention, the second spring member of the leaf spring is elastically deformed according to the displacement of the pressure receiving portion, and the first spring member of the leaf spring provided with the second spring member at the central portion is also elastically deformed. Due to the elastic deformation of the first spring member, a strain, that is, a tensile force or a compressive force is applied to the optical fiber held by the holding portion of the first spring member.
For this reason, a configuration capable of measuring with high accuracy without being affected by electromagnetic noise even in an environment where electromagnetic noise is generated, and preventing damage to the optical fiber even when excessive pressure is applied to the pressure receiving portion, is the center of the first spring member of the leaf spring. The second spring member of the leaf spring is provided with a simple structure and can be easily manufactured.

Furthermore, in the present invention, the first spring member includes a leaf spring-shaped pedestal portion having an intermediate portion attached to the housing and end portions to which the holding portions of the first spring member are respectively attached. It is preferable that
According to the present invention, the first spring member is configured by attaching the holding portions to the end portions of the leaf spring-shaped pedestal portions whose intermediate portions are fixedly mounted in the casing. Accordingly, the first spring member provided with the pedestal portion is elastically deformed corresponding to the elastic deformation of the second spring member, and constitutes a link mechanism that applies a tensile force or a compressive force to the optical fiber.
For this reason, a configuration that can accurately measure even in an environment where electromagnetic noise is generated without being affected by the electromagnetic noise, and that can prevent damage to the optical fiber even when excessive pressure is applied to the pressure receiving portion constitutes a link mechanism using a leaf spring. It is obtained with a simple structure and can be easily manufactured. Furthermore, since the link mechanism is configured, it is possible to accurately measure even a minute pressure of, for example, about 0.1 kPa to 3 kPa.

And in this invention, the said 1st spring member was provided in the state which curves from the said intermediate part of the leaf | plate spring-shaped holding part attached to the said base part in the state curved from the said center part, and the said base part. It is preferable that at least one of a leaf spring-like spring plate portion is provided, and the spring plate portion is configured to be able to hold the optical fiber while the holding portion is attached thereto.
In this invention, the holding portion is configured to be a leaf spring attached to the pedestal portion so as to bend from the central portion, or the holding portion is attached to the pedestal portion so that the spring plate portion is bent from the intermediate portion and holds the optical fiber. It is configured as a possible leaf spring. As a result, the optical fiber is directly attached to the curved holding portion or the spring plate portion that constitutes the link mechanism that is favorably elastically deformed by the elastic deformation of the second spring member, thus simplifying the configuration and facilitating reduction in size and weight. In addition, the productivity can be improved and the manufacturing cost can be easily reduced.

In the present invention, the first spring member is provided with a pair of holding portions extending in opposite directions at the central portion, and both ends are held between the tips of the pair of holding portions. A structure having a leaf spring-like deformed leaf spring portion having a curved portion that is curved in the longitudinal direction at an intermediate portion, and the optical fiber is held by positioning the fiber Bragg grating on the curved portion of the deformed leaf spring portion It is preferable that
In the present invention, both ends of a leaf spring-like deformed leaf spring portion in which a curved portion that is curved in the longitudinal direction is provided in the middle portion between the distal ends of the holding portions provided to extend in opposite directions from the center portion are held. The fiber Bragg grating is positioned at the curved portion to hold the optical fiber. As a result, the holding portion is elastically deformed corresponding to the elastic deformation of the second spring member, and the curved portion of the deformed leaf spring portion provided in an arcuate shape with both ends held by the holding portion is extended. Elastically deformed. Due to the elastic deformation of the curved portion, the fiber Bragg grating tensile force or compressive force of the optical fiber is applied.
For this reason, it is possible to measure accurately without being influenced by electromagnetic noise even in an environment where electromagnetic noise is generated, and the curved portion of the deformed leaf spring portion acts on the first spring member that is elastically deformed even when excessive pressure is applied to the pressure receiving portion. Thus, damage can be prevented without applying a large load to the optical fiber, and the first spring member of the leaf spring can be obtained with a simple structure and can be easily manufactured.

Furthermore, in this invention, it is preferable that the said curved part is set as the structure curved in the state which protrudes on the opposite side to the direction which opposes the said center part.
In the present invention, the curved portion is curved so as to protrude to the side opposite to the direction corresponding to the central portion.
For this reason, even if the pressure receiving portion is displaced, it does not interfere with the bending portion, so that the displacement of the pressure receiving portion can be detected appropriately.

Moreover, in this invention, it is preferable that the said holding | maintenance part of a said 1st spring member is set as the structure by which the fixing | fixed part attached in the said housing | casing is provided in the edge part on the opposite side to the said center part.
In this invention, a 1st spring member is attached in a housing | casing by attaching the fixing | fixed part provided in the edge part on the opposite side to the center part in the holding | maintenance part of a 1st spring member in a housing | casing.
For this reason, the first spring member of the leaf spring has a simple structure in which a central portion is provided on one end side and a fixing portion is provided on the other end side, and can be easily manufactured.

Furthermore, in the present invention, it is preferable that a pair of the holding portions is provided in the central portion so as to extend in opposite directions.
In the present invention, a pair of holding portions each having a fixing portion at an end portion are provided in the central portion in a state of extending in opposite directions.
For this reason, the elastic deformation of the second spring member provided in the central portion causes the pair of holding portions to be elastically deformed, and even if an excessive pressure is applied to the pressure receiving portion as compared with the configuration in which one holding portion is provided. Inconveniences such as damage can be prevented. Further, since the central portion is held by the pair of holding portions, it is possible to prevent the inconvenience that the central portion vibrates even when vibration is applied from the outside, and noise can be satisfactorily measured.

In the present invention, it is preferable that the optical fiber is integrally attached so that at least the fiber Bragg grating is covered with an adhesive.
In this invention, the optical fiber is integrally attached with at least the fiber Bragg grating covered with an adhesive.
For this reason, the elastic deformation of the first spring member directly acts on the fiber Bragg grating and can be measured well. Furthermore, there is no inconvenience that the first spring member is a leaf spring, and even if the force acting on the fiber Bragg grating differs depending on the surface on which the fiber Bragg grating is attached, the measurement cannot be performed because the optical fiber is bent. Can be measured well.

Furthermore, in the present invention, it is preferable that the optical fiber has a configuration in which a plurality of the fiber Bragg gratings are provided and the fiber Bragg gratings are positioned and held at corresponding positions on both surfaces of the first spring member.
In this invention, the optical fiber is held by positioning the fiber Bragg grating at corresponding positions on both surfaces of the leaf spring-shaped first spring member. Accordingly, a tensile force or a compressive force acts on the fiber Bragg grating attached to one surface of the first spring member due to elastic deformation of the first spring member, and the fiber attached to the other surface of the first spring member. A compressive force or tensile force acts on the Bragg grating.
Therefore, by measuring the difference in the diffraction change of light measured by both fiber Bragg gratings, it is possible to measure with higher accuracy than when measuring the change in light diffraction measured by one fiber Bragg grating. .

Moreover, in this invention, it is preferable to set it as the structure equipped with the control member which controls the elastic deformation more than the predetermined of said 2nd spring member according to the displacement more than the predetermined of the said pressure receiving part.
According to the present invention, the restricting member restricts the second spring member from being elastically deformed to a predetermined level or more due to an excessive pressure that causes the pressure receiving unit to be displaced by a predetermined level or more.
For this reason, it is possible to reliably prevent the damage caused by the large elastic deformation of the second spring member and an excessive tensile force or compressive force acting on the optical fiber via the first spring member.

In the present invention, it is preferable that the restricting member restricts elastic deformation of the second spring member to a predetermined level or more by contacting the pressure receiving portion or the second spring member.
In this invention, when the excessive pressure which displaces a pressure receiving part more than predetermined applies to a pressure receiving part, and a 2nd spring member elastically deforms more than predetermined, a pressure receiving part or the said 2nd spring member contacts a regulation member.
For this reason, with a simple structure in which the regulating member is positioned at a position where the pressure receiving portion on the displacement locus of the pressure receiving portion is displaced by a predetermined amount or a position where the pressure receiving portion is deformed by a predetermined amount on the elastic deformation locus of the second spring member, The protection of the optical fiber is surely obtained.

In the present invention, it is preferable that the restricting member is configured such that grease is applied to a portion where the pressure receiving portion or the second spring member abuts.
In this invention, when the pressure receiving portion is displaced more than a predetermined amount due to excessive pressure and the second spring member is elastically deformed more than a predetermined amount and the pressure receiving portion or the second spring member comes into contact with the regulating member, grease is applied to the contacted portion. Therefore, the impact at the time of contact can be reduced and damage can be prevented. In addition, due to the viscosity of the grease itself, vibrations during movement when moving and detecting spray spray pressure, vibrations of operating equipment such as continuous casting equipment, etc., are controlled against external vibrations with a frequency component of 10 Hz or higher. Indicates function.

And in this invention, it is preferable to set it as the structure which comprised the fiber Bragg grating which is arrange | positioned in the vicinity of the said fiber Bragg grating and detects temperature.
According to the present invention, it is possible to correct the change in the output of the fiber Bragg grating for pressure detection in accordance with the change in the ambient temperature due to the fiber Bragg grating that detects the temperature.
For this reason, for example, even when the ambient temperature changes, such as detection of the spray state of spray in a continuous casting facility, it is possible to detect the spray pressure of the spray with higher accuracy.

The top view which shows the measuring system provided with the spray pressure measuring apparatus in 1st embodiment of this invention. The side view which shows the said measurement system. Explanatory drawing which shows the measurement condition by the said measurement system. The perspective view which notched a part which shows the spray pressure measuring device in this embodiment. Sectional drawing which shows the state which received the pressure from the outside in the said spray pressure measuring device. Sectional drawing which shows the link mechanism which transmits a pressure to the optical fiber in the said spray pressure measuring apparatus. The top view which shows the link mechanism in the said spray pressure measuring apparatus. The top view which shows the base part in the said spray pressure measuring apparatus. The front view which shows the optical fiber fixing | fixed part in the said spray pressure measuring apparatus. The top view which shows the said optical fiber fixing | fixed part. The top view which shows the 1st spring member in the said spray pressure measuring device. Explanatory drawing which shows the measurement condition by the said measurement system. It is a graph which shows the detection signal of the said spray pressure measuring apparatus, a vertical axis | shaft is the spraying pressure of a spray, and a horizontal axis is measurement time. Sectional drawing which shows the link mechanism in the spray pressure measuring apparatus of 2nd embodiment of this invention. Sectional drawing which shows the state which attached the optical fiber of said 2nd embodiment. Sectional drawing which shows the link mechanism in the spray pressure measuring apparatus of 3rd embodiment of this invention. The top view which shows the 1st spring member in the spray pressure measuring apparatus of 4th embodiment of this invention. The top view which shows the 1st spring member in the spray pressure measuring apparatus of 5th embodiment of this invention. Sectional drawing which shows the state which received the pressure from the exterior of the spray pressure measuring apparatus in other embodiment of this invention. The top view which shows the 1st spring member in the spray pressure measuring apparatus in further another embodiment of this invention.

[First embodiment]
Hereinafter, the structure of the measurement system provided with the spray pressure measuring device in the first embodiment of the present invention will be described with reference to the drawings.
In the first embodiment, the configuration for measuring the spraying pressure of the spray provided in the continuous casting facility is exemplified, but the present invention is not limited to this. For example, it can be applied to a device that measures the spray pressure of a spray used in the cooling process of a continuously cast steel sheet, or any other spray that sprays and disperses two liquids, or a mixture of two fluids of liquid and gas. .

[Configuration of measurement system]
As shown in FIGS. 1 and 2, the measurement system 1 includes a dummy bar 10 for continuous casting and a pressure measurement unit 20.
In the dummy bar 10, a dummy bar head 11 and a wide link 12 </ b> A are connected to each other by a shaft 13 so as to be rotatable. Further, the dummy bar 10 is configured such that a plurality of wide links 12A are connected in a belt shape so as to be rotatable with each other by a shaft 13 and a narrow link 12B.
And the dummy bar 10 is moved between the slab guide rolls 4 arrange | positioned below the casting_mold | template 3 of the continuous casting installation 2, as shown, for example in FIG.
Here, the slab guide rolls 4 are paired in the thickness direction of the slab (not shown) that is continuously cast (the thickness direction of the dummy bar 10 in the left-right direction in FIG. 2), and is the moving direction of the dummy bar 10. A plurality of pairs are arranged along the slab moving direction and continuously cast to a predetermined thickness dimension. A plurality of sprays 5 are arranged between the slab guide rolls 4 arranged side by side in the slab moving direction. Specifically, a plurality of sprays 5 are arranged in the width direction of the cast slab to be cast (the width direction of the dummy bar 10 in the left-right direction in FIG. 1), and a plurality of sprays 5 are arranged between the slab guide rolls 4. Yes.
Further, a pressure measurement unit 20 is provided on any one of the wide links 12A of the dummy bar 10.

As shown in FIGS. 1 and 2, the pressure measuring unit 20 obtains detection signals detected by the sensor unit 21 in which a plurality of spray pressure measuring devices 200, which will be described in detail later, and a plurality of spray pressure measuring devices 200 are detected. And a data processing unit 22 for processing, and an optical fiber cable 23 (see FIG. 3) for connecting the data processing unit 22 to each spray pressure measuring device 200. 1 shows twelve spray pressure measuring devices 200 for convenience of explanation, this is not restrictive.
The data processing unit 22 includes a light source (not shown) that supplies light to each spray pressure measuring device 200 via the optical fiber cable 23. Further, the data processing unit 22 includes a processing unit (not shown) that detects a reflection wavelength at which the light supplied from the light source is shifted according to the pressure by the spray pressure measuring device 200 and calculates the spray pressure of the spray 5. .

[Configuration of spray pressure measuring device]
Next, the configuration of the spray pressure measuring device will be described in detail based on the drawings.
FIG. 4 is a perspective view with a part cut away showing the spray pressure measuring device. FIG. 5 is a cross-sectional view showing a state in which pressure is received from the outside in the spray pressure measuring device. FIG. 6 is a cross-sectional view showing a link mechanism for transmitting pressure to the optical fiber in the spray pressure measuring device. FIG. 7 is a plan view showing a link mechanism in the spray pressure measuring device. FIG. 8 is a plan view showing a pedestal portion in the spray pressure measuring device. FIG. 9 is a front view showing an optical fiber fixing part in the spray pressure measuring device. FIG. 10 is a plan view showing the optical fiber fixing portion. FIG. 11 is a plan view showing a first spring member in the spray pressure measuring device.

As shown in FIGS. 4 and 5, the spray pressure measuring device 200 includes a casing 210, a pressure receiving part 220, a pedestal part 230, an optical fiber fixing part 240, an optical fiber 250, a first spring member 260, A two-spring member 270 and a regulating member 280 are provided.
The casing 210 is hollow and has a substantially rectangular shape. For example, a substantially circular opening 211 is formed on one surface of the housing 210. A cylindrical guide tube portion 212 having the same inner diameter is provided at the opening edge of the opening portion 211 in series. The housing 210 is provided with a cable connection opening 213. A connector (not shown) to which the optical fiber cable 23 is connected is attached to the cable connection opening 213.
The opening 211 of the housing 210 is provided with a pressure receiving part 220 that is displaced according to the spray pressure of the spray 5.

The pressure receiving unit 220 is a sheet that closes the opening 211 and is deformed when the spray pressure of the spray 5 is applied, and the pressure that moves along the axial direction of the opening 211 due to the deformation of the rubber receiving unit 221. And a transmission unit 222.
The rubber pressure receiving portion 221 is provided with flexibility and water resistance, and is attached by closing the opening 211 in a water-tight manner so that water does not enter the housing 210 from the opening 211.
The pressure transmission part 222 is formed of, for example, a synthetic resin or a light non-ferrous alloy, and has a disk part 222A having substantially the same size as the inner diameter of the opening 211. A series of cylindrical guide flanges 222B having the same outer diameter are provided on the outer peripheral edge of the disc portion 222A. A cylindrical shaft portion 222C is provided at the center of the surface of the disc portion 222A on the side from which the guide flange portion 222B protrudes. A cylindrical positioning pin 222D is provided on the tip surface of the shaft portion 222C so as to protrude coaxially. When the pressure transmitting unit 222 moves, the guide rod unit 222B is guided by the guide tube unit 212 of the opening 211, and the disc unit 222A is arranged to be movable in the axial direction without being inclined.

A pedestal portion 230 is provided in the housing 210. As shown in FIGS. 4 to 8, the pedestal portion 230 is formed as a longitudinal leaf spring by, for example, etching and bending a stainless steel plate of 0.3 mm to 0.5 mm.
The pedestal portion 230 is provided with a first folding line 231 along the width direction located at an intermediate portion in the longitudinal direction. Further, the pedestal portion 230 is provided with second folding lines 232 along the width direction at both ends in the longitudinal direction. The pedestal portion 230 has a mounting plate portion 233 attached to the housing 210 between the first folding lines 231, and the mounting plate portion 233 is between the first folding line 231 and the second folding line 232. A spring plate portion 234 that is elastically deformed is defined, and an attachment fixing plate portion 235 that is elastically deformed with respect to the spring plate portion 234 is defined from the second folding line 232 to the end side.
In addition, the pedestal portion 230 is provided with a thin-wall processed portion 236 that is positioned on the first fold line 231 and the second fold line 232 and is thinly processed into a strip shape along the width direction. These thin-wall processed portions 236 are provided on a surface that is mountain-folded at the positions of the first fold curve 231 and the second fold curve 232. Further, the thin-walled processing unit 236 is provided with a hole processing unit 237 that is formed into a substantially elliptical shape. The thin wall processed part 236 and the hole processed part 237 facilitate elastic deformation at the positions of the first fold line 231 and the second fold line 232. In FIG. 8, for the convenience of explanation, description will be given with 12 hole processing portions 237 provided in three locations, but the size and number are appropriately set according to the required spring constant. Similarly, the width dimension and depth dimension in the thin-wall processed portion 236 are also set as appropriate. Note that only one of the thinned portion 236 and the hole processed portion 237 may be provided, or both may be provided.
Further, the mounting plate portion 233 of the pedestal portion 230 has a mounting piece having a screw hole 239A that protrudes in the form of a tongue piece on both sides in the longitudinal direction and is fixedly attached to the bottom surface of the housing 210 with bolts 238A and nuts 238B. A portion 239 is provided in series.

As shown in FIGS. 4 to 7, 9, and 10, optical fiber fixing portions 240 are respectively provided on the mounting fixing plate portion 235 of the pedestal portion 230.
The optical fiber fixing part 240 is formed in a flat rectangular shape with, for example, glass or a light non-ferrous metal. The optical fiber fixing portion 240 is provided with a through hole 241 that penetrates the optical fiber 250 in the width direction. The through-hole 241 includes a small-diameter portion 241A through which the optical fiber 250 can penetrate and a large-diameter portion 241B having a diameter larger than that of the small-diameter portion 241A and continuing coaxially.
On the front and back planes of the optical fiber fixing portion 240, an attachment step portion 242 having substantially the same size as the width of the attachment fixing plate portion 235 of the pedestal portion 230 is provided. The optical fiber fixing portion 240 is integrally attached in a state where the attachment fixing plate portion 235 is inserted into the attachment stepped portion 242. In this attached state, the small diameter portions 241 </ b> A are opposed to each other at both ends in the longitudinal direction of the pedestal portion 230. The attachment method can be attached by various methods such as adhesion and screwing.
Then, the optical fiber 250 is inserted through the through holes 241 of the pair of optical fiber fixing portions 240 attached to the pedestal portion 230, and is stretched with a small tensile force that does not loosen. Various methods such as adhesion, caulking, low-melting glass, or soldering can be applied to the optical fiber 250. 4 and 5, the material for attaching the optical fiber 250 is omitted for convenience of explanation.

The optical fiber 250 has a fiber Bragg grating for pressure detection (hereinafter referred to as FBG (Fiber Bragg Gratings)) 251 and an FBG 252 for temperature correction. The temperature correcting FBG 252 is provided near the end of the optical fiber 250. 5 and 6, for convenience of explanation, the FBGs 251 and 252 are represented by three parallel inclined lines.
The optical fiber 250 is attached so that the FBG 251 for pressure detection is positioned at the center between the pair of optical fiber fixing portions 240, that is, at an intermediate point that is equidistant from the optical fiber fixing portion 240. Further, the end of the optical fiber 250 that is inserted through the through hole 241 of the optical fiber fixing portion 240 on the side opposite to the cable connection opening 213 is folded without being broken.

Here, the FBGs 251 and 252 form a Bragg diffraction grating in the core of the optical fiber 250 by, for example, ultraviolet rays, and reflect light having a specific wavelength determined by the grating interval. This reflection of light reflects light supplied from the light source of the data processing unit 22 via the optical fiber cable 23. The reflected light is again measured by the data processing unit 22 via the optical fiber cable 23.
The relationship between the lattice spacing and the wavelength of the FBGs 251 and 252 is expressed by the following formula (1).
{Formula (1)}
λ = 2n × D (1)
λ: reflection wavelength
n: Average refractive index of FBG
D: Grating spacing And the wavelength change is detected by the following formula (2).
{Formula (2)}
Δλ = 2n × ΔD + 2Δn × D (2)
Δ: represents the amount of change of each parameter.
As shown in equation (2), when Δn = 0, when D changes by ΔD due to external stress, the wavelength changes by Δλ, and the wavelength change is detected.
Further, when the ambient temperature of the FBG 251 changes, Δλ changes.
When temperature is represented by T, it is known that n and D are functions of temperature, and n is also a function of wavelength. From this, in the linear region, the change amounts of n and D are expressed by the following equations (3) and (4).
{Formula (3)}
Δn = s (ΔT) (3)
s: Refractive index temperature coefficient {Formula (4)}
ΔD = ρ (ΔT) (4)
ρ: Linear expansion coefficient In this way, the temperature dependency is shared by the two FBGs 251 and 252, and the difference in wavelength change due to the spray pressure of the spray 5 applied to one FBG 251 is caused by the temperature change of the other FBG 252. The error is compensated.

A first spring member 260 is integrally attached to the pedestal portion 230. As shown in FIGS. 4 to 7 and 11, the first spring member 260 is formed in a longitudinal shape by etching and bending a stainless steel plate of 0.3 mm to 0.5 mm, for example, like the pedestal portion 230. It is formed in the leaf spring.
The first spring member 260 is provided with a first folding line 261 along the width direction located in the middle portion in the longitudinal direction. Further, the first spring member 260 is provided with second folding lines 262 along the width direction at both ends in the longitudinal direction. The first spring member 260 has a pressure receiving plate portion 263 as a central portion that receives the displacement of the pressure transmitting portion 222 between the first folding lines 261. The first spring member 260 has a spring portion 264 that is elastically deformed with respect to the pressure receiving plate portion 263 between the first fold line 261 and the second fold line 262. Further, a connecting plate portion 265 as a holding portion that is elastically deformed with respect to the spring portion 264 is defined in the first spring member 260 on the end side from the second folding line 262. The connecting plate portion 265 is attached to the optical fiber fixing portion 240 to which the optical fiber 250 is attached, and is attached to the attachment fixing plate portion 235 of the pedestal portion 230 via the optical fiber fixing portion 240. In a state where the optical fiber 250 is attached, the pressure receiving plate portion 263 faces the FBG 251 of the optical fiber 250. That is, the optical fiber 250 is stretched between the optical fiber fixing portions 240 in a state where the FBG 251 is located at the center.
In addition, the first spring member 260 is provided with a thin portion 266 that is located in the first fold line 261 and the second fold line 262 and is thinned into a strip shape along the width direction. These thin portions 266 are provided on a surface that is mountain-folded at the positions of the first fold line 261 and the second fold line 262. Further, the thin portion 266 is provided with a hole portion 267 that is formed into a substantially elliptical shape. These thin portions 266 and holes 267 facilitate elastic deformation at the positions of the first fold line 261 and the second fold line 262. For convenience of explanation, FIG. 11 will be described with three holes 267 provided in three places, but the size and number are appropriately set according to the required spring constant. Similarly, the width dimension and depth dimension in the thin portion 266 are also set as appropriate. Note that only one of the thin-walled portion 266 and the hole portion 267 may be provided, or a configuration may be provided in which neither is provided.
The first spring member 260 is integrally attached in the same manner as the pedestal portion 230 with the connecting plate portion 265 inserted into the attachment stepped portion 242 of the optical fiber fixing portion 240. By this attachment, the pedestal portion 230 and the first spring member 260 constitute a pantograph-like link mechanism having a flat diamond shape.

Further, as shown in FIGS. 4 to 7 and 11, a second spring member 270 is formed on the pressure receiving plate portion 263 located at the center in the longitudinal direction of the first spring member 260. The second spring member 270 is a leaf spring formed by punching the pressure receiving plate portion 263 into a mainspring shape.
The second spring member 270 has a disk-shaped pressing plate portion 271 having a positioning hole 271A into which the positioning pin 222D of the pressure transmission portion 222 is inserted. In the radial direction of the outer peripheral edge of the pressing plate portion 271, a pair of elastic plate portions 272 are provided in a circular arc shape along the outer peripheral edge and the tip portion is connected to the pressure receiving plate portion 263 of the first spring member 260. . Then, as shown in FIG. 5, the second spring member 270 is pushed into the pressing plate portion 271 by the displacement of the pressure transmitting portion 222 attached to the pressing plate portion 271 and receiving pressure, that is, toward the pedestal portion 230. The pair of elastic plate portions 272 are elastically deformed so as to move.
The spring constant of the second spring member 270 is smaller than the spring constant of the first spring member 260. That is, when the same pressure is applied, the second spring member 270 is elastically deformed with a displacement larger than the first spring member 260.
Then, in response to the elastic deformation of the second spring member 270, the pressure receiving plate portion 263 of the first spring member 260 that is continuously provided with the elastic plate portion 272 that is elastically deformed is also moved toward the pedestal portion 230. The member 260 is elastically deformed. In response to the elastic deformation of the first spring member 260, the pedestal portion 230 connected via the optical fiber fixing portion 240 is also elastically deformed so as to be crushed. Such an elastic deformation that collapses the pantograph-like flat rhombus link mechanism causes distortion, that is, tensile force, acts on the optical fiber 250.

Here, the pantograph-like link mechanism is formed in a flat rhombus having four points of the second spring member 270, the pair of optical fiber fixing portions 240, and the mounting plate portion 233 of the base portion 230. That is, in the link mechanism, the diagonal M between the vertex A corresponding to the second spring member 270 and the vertex C corresponding to the mounting plate portion 233 is more than the diagonal N between the vertices B and D corresponding to the pair of optical fiber fixing portions 240. It is a flat rhombus that shortens.
From this, when the spraying pressure of the spray 5 is applied to the second spring member 270, the vertex A moves toward the vertex C in a state where the diagonal M becomes shorter, and the diagonal N becomes longer and pulls the optical fiber 250. The vertices B and D move in a direction away from each other. The distance ΔN that moves in the direction in which the vertices B and D move away is shorter than the distance ΔM that the vertex A moves toward the vertex C. Further, according to the law of conservation of energy, the energy Ep received by the second spring member 270 corresponding to the spray pressure of the spray 5 and the energy Ef pulling the optical fiber 250 are substantially the same.
For this reason, the tensile force Ff (= Ef / ΔN) of the optical fiber 250 at the vertices B and D where the movement amount is small becomes larger than the spray ejection pressure Fp (= Ep / ΔM) at the vertex A where the movement amount is large. Therefore, the flat rhombus link mechanism can accurately detect even a small spray pressure of the spray 5.

Further, as shown in FIGS. 4, 5, and 7, a regulating member 280 is disposed in the housing 210. The restricting member 280 is formed in a longitudinal plate shape with, for example, a steel plate. The regulating member 280 is fixedly attached to the mounting member 285 provided at the casing 210 at both ends in the longitudinal direction so as to penetrate through the link mechanism. That is, the regulating member 280 is disposed in a state of facing the surface of the second spring member 270 opposite to the side on which the pressure transmission unit 222 is attached.
The restriction member 280 is a position where the tip of the positioning pin 222D of the pressure transmission part 222 comes into contact with the pressure transmission part 222 when the excessive pressure is applied and the pressure transmission part 222 is greatly displaced, so that the pressure transmission part 222 cannot be displaced any more. It is arranged. Due to the restriction of the displacement of the pressure transmission part 222, the amount of elastic deformation of the second spring member 270 to which the pressure transmission part 222 is attached and the first spring member 260 provided with the second spring member 270 is also restricted. For this reason, damage such as cutting due to excessive tensile force acting on the optical fiber 250 is prevented.
As shown in FIG. 5, grease 286 is provided at a position where the pressure transmission unit 222 abuts.
Note that the facing distance between the regulating member 280 and the second spring member 270 for regulating the amount of displacement of the pressure transmission unit 222 can be changed by shifting the mounting position of the mounting member 285.
In addition, the regulating member 280 is attached with an FBG 252 at an end portion that is turned through the through hole 241 of the optical fiber fixing portion 240 in the optical fiber 250. As shown in FIG. 5, the FBG 252 is attached to the surface of the regulating member 280 opposite to the surface facing the second spring member 270 with an adhesive 287 or the like so as to face the FBG 251.

[Measurement of spray pressure]
Next, a method for measuring the spray pressure of the spray 5 in the continuous casting facility 2 using the measurement system 1 will be described with reference to the drawings.
FIG. 12 is an explanatory diagram showing a measurement situation by the measurement system 1. FIG. 13 is a graph showing detection signals detected by the spray pressure measuring device, in which the vertical axis represents the spray pressure and the horizontal axis represents the measurement time.

The measuring system 1 in which the pressure measuring unit 20 is previously disposed on the dummy bar 10 is moved between the slab guide rolls 4 disposed below the mold 3 of the continuous casting facility 2. The movement between the slab guide rolls 4 of the measurement system 1 is performed by rotating the slab guide rolls 4 by a drive motor or the like connected to the slab guide rolls 4 in the lower side in FIGS. To do.
When the measuring system 1 is moved, as shown in FIG. 12, water or two fluids mixed with water and air are ejected from the spray 5. When the spray pressure measuring device 200 of the moving measuring system 1 passes through the spray flow 5A of the spray 5, the spray flow 5A comes into contact with the rubber pressure receiving portion 221, and the pressure transmitting portion 222 is displaced as shown in FIG. To do. Specifically, the pressure transmission part 222 is guided by the guide cylinder part 212 of the opening 211 against the elasticity of the pedestal part 230, the first spring member 260 and the second spring member 270. Then, it moves so as to advance into the housing 210.

Due to the displacement of the pressure transmission part 222, the pair of elastic plate parts 272 are elastically deformed so that the pressing plate part 271 of the second spring member 270 moves toward the base part 230. In response to the elastic deformation of the second spring member 270, the pressure receiving plate portion 263 of the first spring member 260 connected to the elastic plate portion 272 that is elastically deformed is also crushed so as to be moved toward the pedestal portion 230. The first spring member 260 is elastically deformed. In response to the elastic deformation of the first spring member 260, the pedestal portion 230 connected via the optical fiber fixing portion 240 is also elastically deformed so as to be crushed.
By such elastic deformation that the flat diamond-like link mechanism like a pantograph is crushed, the space between the optical fiber fixing portions 240 is expanded, and a tensile force acts on the optical fiber 250.

When a tensile force corresponding to the spray pressure of the spray 5 acts on the optical fiber 250, the wavelength of light supplied from the light source of the data processing unit 22 through the optical fiber cable 23 and reflected by the FBG 251 changes. The spray pressure of the spray 5 is calculated from this wavelength change. Specifically, from the difference in wavelength change of the pressure detecting FBG 251, the difference in wavelength change due to the temperature change of the temperature correcting FBG 252 is compensated as an error due to the temperature change, and the spray pressure of the spray 5 is calculated.
Such detection of the spray pressure of the spray 5 is detected for each spray 5 that passes through the movement of the measurement system 1. For example, as shown in FIG. 13, in the spray 5 that normally ejects, the detection result indicates that the spray ejection pressure is detected in a peak shape. On the other hand, when cooling by the spray 5 cannot be performed properly, such as when the nozzle is blocked or not properly ejected, or there is a shield and the spray flow 5A does not reach the pressure receiving portion 220, from the left in FIG. As with the third nozzle, no peak can be detected, and it can be determined that the nozzle is defective.
Thus, the spraying pressure can be detected by the data processing unit 22 and the spraying state can be appropriately determined.

When an excessive pressure suddenly acts on the pressure receiving part 220 at the time of detecting the ejection pressure, the pressure transmission part 222 is displaced to a state in which the second spring member 270 is largely elastically deformed. On the other hand, since the first spring member 260 connected to the second spring member 270 has a larger spring constant than the second spring member 270, it is elastically deformed with a relatively small amount of displacement.
Therefore, a large tensile force does not act on the optical fiber 250, and damage such as disconnection of the optical fiber 250 can be prevented.
Furthermore, when a large excessive pressure is applied, the pressure transmission unit 222 is displaced further greatly, but abuts against the regulating member 280 and cannot be displaced any more.
As described above, even if an excessive pressure is applied, a large tensile force does not act on the optical fiber 250, and it is possible to reliably prevent damage such as disconnection of the optical fiber 250.

[Effects of Embodiment]
In the first embodiment, the optical fiber 250 provided with the FBG 251 is used for detection of the spray pressure of the spray 5.
For this reason, even in an environment where electromagnetic noise occurs, measurement can be performed with high accuracy without being affected by electromagnetic noise.
The first spring member 260 that holds the optical fiber 250 is provided with a second spring member 270 having a smaller spring constant than the first spring member 260 so as to be elastically deformed in accordance with the displacement of the pressure transmission unit 222.
Therefore, even if an excessive pressure is applied and the pressure transmission part 222 is greatly displaced, the second spring member 270 is greatly elastically deformed, and the first spring member 260 that holds the optical fiber 250 has a relatively small elastic deformation amount. Become. Accordingly, it is possible to prevent a sudden large tensile force from acting on the optical fiber 250 and to prevent damage such as disconnection of the optical fiber 250.

In the first embodiment, the second spring member 270 of the leaf spring is elastically deformed according to the displacement of the pressure transmission unit 222, and the first spring member of the leaf spring provided with the second spring member 270 in the center. 260 is also elastically deformed. Due to the elastic deformation of the first spring member 260, both ends of the optical fiber 250 are held by the first spring member 260 in a state where the FBG 251 is located in the center in the longitudinal direction, and the optical fiber 250 stretched in an arcuate shape according to the pressure. A tensile force is applied.
For this reason, even if an excessive pressure is applied to the pressure transmission unit 222, a configuration that can prevent the optical fiber 250 from being damaged can be obtained with a simple structure in which the second spring member 270 of the leaf spring is provided at the center of the first spring member 260 of the leaf spring. It is done. Therefore, it is possible to easily reduce the size and improve the manufacturability by simplifying the structure.

In addition, both longitudinal end portions of the first spring member 260 are respectively attached to both longitudinal end portions of a plate spring-like pedestal portion 230 whose longitudinal intermediate portions are attached and fixed in the casing 210.
Accordingly, the first spring member 260 and the pedestal portion 230 constitute a link mechanism that elastically deforms in response to the elastic deformation of the second spring member 270 and applies a tensile force to the optical fiber 250. For this reason, even if an excessive pressure is applied to the pressure transmission part 222, the structure which can prevent the damage of the optical fiber 250 is obtained with the simple structure which comprises a link mechanism using a leaf | plate spring. Therefore, it is possible to easily reduce the size and improve the manufacturability by simplifying the structure. Furthermore, since the link mechanism is configured, it is possible to accurately measure even a minute pressure of, for example, about 0.1 kPa to 3 kPa.

And the thin part 236 and the hole processing part 237 are provided in the base part 230, and the thin part 266 and the hole part 267 are provided in the 1st spring member 260, and it is set as the structure which elastically deforms.
For this reason, it is easy to design a predetermined spring constant with a simple structure.
The mounting fixing plate portion 235 and the spring plate portion 234 in the pedestal portion 230 are connected to each other at four locations by a thin wall processing portion 236 having three hole processing portions 237. In addition, the spring plate portion 234 and the mounting plate portion 233 in the base portion 230 are also connected to each other at four places by the thin wall processing portion 236. Similarly, the first spring member 260 is also configured to be connected at four locations by a thin portion 266 having three holes 267. For this reason, for example, in the pedestal portion 230, even if an external force is applied so that the spring plate portion 234 and the mounting fixing plate portion 235 are twisted, the structure is connected at a plurality of locations, so that the structure is connected at one location. Thus, twisting can be prevented. Therefore, a link mechanism that can be elastically deformed satisfactorily can be constructed with a simple configuration of thin wall processing and drilling processing.

Further, the restricting member 280 restricts the second spring member 270 from being elastically deformed to a predetermined level or more by applying an excessive pressure to the pressure transmitting unit 222 so that the pressure transmitting unit 222 is displaced by a predetermined value or more.
Therefore, it is possible to reliably prevent the second spring member 270 from being elastically deformed and the first spring member 260 from being largely elastically deformed, and an excessive tensile force acting on the optical fiber 250 to be damaged.

When the second spring member 270 is elastically deformed more than a predetermined amount due to an excessive pressure that causes the pressure transmission unit 222 to be displaced more than a predetermined value, the position where the pressure transmission unit 222 abuts the regulating member 280. A restricting member 280 is provided on the surface.
For this reason, the regulating member 280 may be positioned so that the pressure transmitting portion 222 contacts at a position where the pressure transmitting portion 222 is displaced by a predetermined amount on the locus where the pressure transmitting portion 222 is displaced, and the regulating member 280 is only formed in a plate shape. Thus, it is possible to obtain a simple structure that is arranged so as to cross the link mechanism, and to reliably protect the optical fiber 250 against excessive pressure.

Further, the pressure transmission part 222 is displaced more than a predetermined value due to excessive pressure, the second spring member 270 is elastically deformed more than a predetermined value, and grease 286 is applied to a part where the pressure transmission part 222 contacts the regulating member 280. .
For this reason, the impact at the time of contact when an excessive pressure is suddenly applied can be reduced, and damage can be prevented. In addition, due to the viscosity of the grease 286 itself, the dummy bar 10 moves to detect the spray pressure of the spray 5 and the vibration at the time of movement, the vibration of the operating equipment such as the continuous casting equipment, etc. The vibration control function against vibrations of the

Further, an FBG 252 for temperature correction is disposed in the vicinity of the FBG 251 for pressure detection.
Therefore, the FBG 252 can compensate for the wavelength change of the reflected light detected by the FBG 251 in accordance with the change in the ambient temperature of the FBG 251, and can detect the spray ejection pressure with higher accuracy.
Further, the FBG 252 is provided in the optical fiber 250 provided with the FBG 251.
For this reason, it is only necessary to provide one optical fiber 250, and the productivity can be improved.

[Second Embodiment]
Next, the spray pressure measuring device in 2nd embodiment of this invention is demonstrated with reference to FIG. 14 and FIG.
FIG. 14 is a cross-sectional view showing a link mechanism in the spray pressure measuring device according to the second embodiment of the present invention. FIG. 15 is a cross-sectional view showing a state where an optical fiber FBG is attached in the spray pressure measuring apparatus of the second embodiment.
In the second embodiment shown in FIGS. 14 and 15, the same or similar configurations as those in the first embodiment are denoted by the same names and reference numerals, and the description thereof is omitted or simplified.

  In the second embodiment shown in FIG. 14, the first spring member of the present invention is configured and held by the first spring member 260 instead of the optical fiber 250 between the optical fiber fixing portions 240 to which the optical fiber 250 in the first embodiment is attached. A plate spring-like deformed leaf spring portion 290 that functions as a portion is provided. That is, in the second embodiment, the deformed leaf spring portion 290 of the leaf spring is caused to function as a part of the first spring member 260. More specifically, as the first spring member of the present invention, a first spring member 260 as a first spring member main body and a deformed leaf spring portion 290 held between both longitudinal ends of the first spring member 260. It is set as the structure provided with.

Similar to the first spring member 260, the deformed leaf spring portion 290 is formed of a longitudinal leaf spring, and has a curved portion 291 that curves to one surface side in the center portion in the longitudinal direction.
The deformed leaf spring portion 290 is disposed between the optical fiber fixing portions 240 in a state where the bending portion 291 protrudes on the opposite side of the first spring member 260 from the side facing the pressure receiving plate portion 263. Specifically, both end portions in the longitudinal direction are integrally attached to the optical fiber fixing portion 240 attached to the connecting plate portion 265 of the first spring member 260 and arranged so as to be bridged between the optical fiber fixing portions 240. Has been.
The FBG 251 of the optical fiber 250 is integrally attached along the longitudinal direction of the deformed leaf spring portion 290 on the outer surface side of the curved portion 291 of the deformed leaf spring portion 290. For example, as shown in FIG. 15, the attachment is integrally performed so that the FBG 251 is covered with an adhesive 292. That is, the optical fiber 250 is held by the adhesive 292 on the curved portion 291 of the deformed leaf spring portion 290.
Note that various adhesives such as an epoxy resin can be used as the adhesive. In an environment where a heat load is applied, a heat resistant material may be used.

When the spray pressure of the spray 5 is measured, if the pressure transmission part 222 is displaced against the elasticity of the pedestal part 230, the first spring member 260 and the second spring member 270, the deformation leaf spring part 290 is distorted. Specifically, a compressive force is applied, and the bending portion 291 is elastically deformed so as to be extended. That is, when the second spring member 270 is elastically deformed, the spring portion 264 of the first spring member 260 is elastically deformed, and the displacement leaf spring portion connected to the spring portion 264 via the connecting plate portion 265 and the optical fiber fixing portion 240. Propagating to 290, the bending portion 291 of the displacement leaf spring portion 290 is elastically deformed.
Due to the elastic deformation of the curved portion 291, a compressive force acts on the FBG 251, and the wavelength of light reflected by the FBG 251 changes. The jet pressure can be measured by calculating the jet pressure of the spray 5 by this wavelength change.

In the second embodiment, similarly to the effects of the first embodiment, the second spring member 270 is greatly elastically deformed and holds the optical fiber 250 even in a situation where the excessive pressure is applied and the pressure transmission part 222 is largely displaced. The first spring member 260 has a relatively small amount of elastic deformation. Therefore, it is possible to prevent a large compressive force from acting on the optical fiber 250 and to prevent damage such as disconnection or bending of the optical fiber 250.
Furthermore, in the second embodiment, since the elastic deformation of the first spring member 260 elastically deforms the deformation leaf spring portion 290, the elastic deformation amount smaller than the elastic deformation amount of the first spring member 260 in the first embodiment is FBG251. As a result, damage such as disconnection of the optical fiber 250 can be prevented.
In addition, since the FBG 251 of the optical fiber 250 is attached to the displacement leaf spring portion 290 so as to be adhered by the adhesive 292, the assembly work is easier than in the case where the optical fiber 250 in the first embodiment is stretched. Thus, the inconvenience of cutting the optical fiber 250 does not occur, and the productivity can be further improved.
Since the deformed leaf spring portion 290 is provided in a state where the bending portion 291 is bent toward the pedestal portion 230, the bending portion 291 does not interfere with the restricting member 280, and is limited in the limited housing 210. Arrangement can be made well and enlargement can be prevented. In addition, it is not restricted to the case where it curves toward the base part 230, You may bend in any direction from the point of interference with another site | part, etc.

[Third embodiment]
Next, the spray pressure measuring device in 3rd embodiment of this invention is demonstrated with reference to FIG.
FIG. 16: is sectional drawing which shows the link mechanism in the spray pressure measuring apparatus of 3rd embodiment of this invention.
In the third embodiment shown in FIG. 16, the same or similar configurations as those in the above embodiments are given the same names and reference numerals, and the description thereof is omitted or simplified.

In the third embodiment shown in FIG. 16, the FBG 251 is directly attached to the first spring member 260 of the first embodiment.
Specifically, the first spring member 260 of the third embodiment shown in FIG. 16 is formed of a longitudinal leaf spring in the same manner as the first spring member 260 of the first embodiment, and receives pressure at the center in the longitudinal direction. It has the board part 263, and has the connection board part 265 in the both ends of a longitudinal direction. Between the pressure receiving plate portion 263 and the connecting plate portion 265, a curved spring portion 264 that functions as a holding portion that is continuous with the pressure receiving plate portion 263 without providing the first folding line 261 is provided. A thin portion 266 provided with a second folding line is provided between the spring portion 264 and the connecting plate portion 265.
In the spring portion 264 of the first spring member 260, the FBG 251 is attached to the adhesive 292 along the longitudinal direction of the spring portion 264 along the longitudinal direction of the spring portion 264 on the curved inner side that becomes the surface facing the pedestal portion 230. Are attached together. That is, the optical fiber 250 is held by the adhesive 292 on the spring portion 264 of the first spring member 260.

When the spray pressure of the spray 5 is measured, the pressure transmission part 222 is displaced against the elasticity of the pedestal part 230, the first spring member 260 and the second spring member 270.
Due to the elastic deformation of the first spring member 260, the FBG 251 attached to the inside of the first spring member 260 is distorted, and the wavelength of light reflected by the FBG 251 changes. The jet pressure can be measured by calculating the jet pressure of the spray 5 by this wavelength change.

In the third embodiment, similarly to the above-described embodiments, even if an excessive pressure is applied and the pressure transmission unit 222 is largely displaced, the second spring member 270 is greatly elastically deformed to hold the optical fiber 250. The member 260 has a relatively small amount of elastic deformation. Therefore, it is possible to prevent a large strain from acting on the optical fiber 250 and to prevent damage such as disconnection or bending of the optical fiber 250.
Also, in the third embodiment, as in the second embodiment, the assembly work is easier than in the case of stretching the optical fiber 250 in the first embodiment, and the optical fiber 250 is accidentally cut during the assembly work. No inconvenience occurs, and the productivity can be further improved.
Furthermore, in the third embodiment, it is not necessary to use a separate part such as the deformed leaf spring portion 290 of the second embodiment, the configuration is simplified, the size and weight can be easily reduced, the productivity is improved, and the manufacturing cost is increased. Can be easily reduced.

[Fourth embodiment]
Next, a spray pressure measuring apparatus according to a fourth embodiment of the present invention will be described with reference to FIG.
FIG. 17: is sectional drawing which shows the 1st spring member in the spray pressure measuring apparatus of 4th embodiment of this invention.
In the fourth embodiment shown in FIG. 17, the same or similar configurations as those in the above embodiments are given the same names and reference numerals, and descriptions thereof are omitted or simplified.

In the fourth embodiment shown in FIG. 17, a first leaf spring portion is attached in the housing 210 in place of the pantograph-like link mechanism in the first to third embodiments.
Specifically, the first spring member 260 of the fourth embodiment shown in FIG. 17 is formed as a longitudinal leaf spring. The first spring member 260 has a series of pressure receiving plate portions 263 provided with a second spring member 270 at one end in the longitudinal direction of a rectangular spring portion 264 that functions as a holding portion. Further, the first spring member 260 is provided with a series of attachment fixing portions 269 as fixing portions attached to the attachment base portions 215 protruding from the housing 210 at the other end in the longitudinal direction of the spring portion 264. .
The first spring member 260 has an attachment fixing portion 269 attached to the distal end portion of the attachment base portion 215, and a pressure transmission portion 222 attached to the second spring member 270 on the side opposite to the attachment base portion 215 side. The FBG 251 is adhered to the side of the spring portion 264 of the first spring member 260 on which the pressure transmission portion 222 is attached with the adhesive 292 along the longitudinal direction of the spring portion 264 in the same manner as the second embodiment and the third embodiment. It is attached integrally. That is, the optical fiber 250 is held by the adhesive 292 on the spring portion 264.

When measuring the spray pressure of the spray 5, the pressure transmission unit 222 is displaced against the elasticity of the first spring member 260 and the second spring member 270.
Due to the elastic deformation of the first spring member 260, the FBG 251 is distorted, specifically, a tensile force acts, and the wavelength of light reflected by the FBG 251 changes. The jet pressure can be measured by calculating the jet pressure of the spray 5 by this wavelength change.

In the fourth embodiment, similarly to the above-described embodiments, the first spring that holds the optical fiber 250 is greatly elastically deformed by the second spring member 270 even in a situation where the excessive pressure is applied and the pressure transmission portion 222 is largely displaced. The member 260 has a relatively small amount of elastic deformation. Accordingly, it is possible to prevent a sudden large tensile force from acting on the optical fiber 250 and to prevent damage such as disconnection of the optical fiber 250.
In the fourth embodiment, as in the second embodiment, the assembly work is easier than in the case where the optical fiber 250 in the first embodiment is stretched, and the optical fiber 250 is accidentally cut during the assembly work. No inconvenience occurs, and the productivity can be further improved.
Further, in the fourth embodiment, the structure is simplified and the productivity can be further improved with an extremely simple structure using one longitudinal leaf spring without using the link mechanism as in the above embodiments.
Further, in the fourth embodiment, since the first spring member 260 is linear, temperature correction when measuring in an environment where heat is applied, for example, is relatively performed using the coefficient of thermal expansion of the first spring member 260 itself. Therefore, the temperature can be easily corrected as compared with the configuration using the link mechanism.

[Fifth embodiment]
Next, a spray pressure measuring apparatus according to a fifth embodiment of the present invention will be described with reference to FIG.
FIG. 18 is a cross-sectional view showing a first spring member in the spray pressure measuring device of the fifth embodiment of the present invention.
In the fifth embodiment shown in FIG. 18, the same or similar configurations as those in the above embodiments are given the same names and reference numerals, and the description thereof is omitted or simplified.

In the fifth embodiment shown in FIG. 18, the first spring member 260 of the fourth embodiment has a pair of spring portions 264 and is provided in a state of being bridged between the pair of mounting base portions 215.
The fifth embodiment also has the same effects as the fourth embodiment, and the portions that are elastically deformed from the fourth embodiment are a pair of spring portions 264, so that even a larger pressure can be measured appropriately.
Further, in the fifth embodiment, since the pressure acting on the pressure transmission unit 222 is received by the pair of spring portions 264, the pressure transmission unit 222 is moved in a straight line, and the pressure can be measured with high accuracy and stability.

[Modification]
The present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, although the structure which provided the 2nd spring member 270 of the leaf | plate spring in the center of the longitudinal direction of the 1st spring member 260 of a leaf | plate spring was illustrated, it does not restrict to a leaf | plate spring structure. For example, the second spring member 270 may be formed in a conical coil spring shape.
Further, the structure of the leaf spring is not limited to the structure of a single plate but may be a stacked leaf spring.

And although the 2nd spring member 270 was stamped and formed in the shape of a mainspring spring, it can be set as not only this shape but any shape which is more easily elastically deformed than the 1st spring member 260.
In addition, by forming in the shape of a mainspring spring, a shape that is easily elastically deformed within a limited range, for example, the elastic plate portion 272 can be formed long, which is preferable.
Furthermore, although the second spring member 270 is provided at the center in the longitudinal direction of the first spring member 260, the present invention is not limited to this. For example, the first spring member 260 may be provided at the end in the longitudinal direction.

  In addition, the first spring member 260 is attached to the pedestal portion 230 of the leaf spring to form the link mechanism, but this is not restrictive. For example, the first spring member 260 is formed in a mainspring shape without using the pedestal portion 230, one end side of the first spring member 260 is pivotally supported, and the second spring member 270 is provided on the other end side. Then, an end portion of the optical fiber 250 is attached to the shaft portion that pivotally supports the first spring member 260, and the first spring member 260 is elastically deformed so that the shaft portion rotates and a tensile force is applied so that the optical fiber 250 is wound. You may make it the structure made to act.

  And although the positioning pin 222D was provided in the pressure transmission part 222, and the structure connected with the 2nd spring member 270 was illustrated, it is not this limitation. For example, the shaft portion 222C may be formed in a cylindrical shape, and a screw that penetrates the positioning hole 271A of the second spring member 270 may be screwed into the shaft portion 222C and attached integrally.

In addition, the restricting member 280 has exemplified a configuration in which the movement is restricted when the pressure transmission unit 222 abuts. However, for example, the restricting member 280 has a position or shape that abuts against the pressing plate portion 271 of the second spring member 270. It is good also as a structure which controls movement by contact | abutting. Furthermore, it is good also as a structure which does not use the separate limitation member 280, but controls movement by contact | abutting to a part of housing | casing 210. FIG. Further, it is not necessary to provide a configuration for restricting movement.
Furthermore, although the regulating member 280 is disposed in a state where the longitudinal direction intersects the longitudinal direction of the optical fiber 250, as shown in FIG. 19, a pair of regulating members 280 are arranged so that the guide flange portion 222B of the pressure transmitting portion 222 abuts. You may set up. Even in such a configuration, it is preferable to provide grease at the abutting portion. In FIG. 19, the same or similar components as those in the embodiment shown in FIGS.
Although the grease 286 is provided, the grease 286 may not be used. Further, as an alternative method of the damping function of the grease 286, for example, silicone oil may be enclosed in the housing 210. Note that the configuration using the grease 286 is preferable because it requires a small amount of material, can be easily manufactured, can prevent an increase in manufacturing cost, and can easily perform internal maintenance management and maintenance inspection.

Further, as in the configuration shown in FIG. 19, if there is a problem such as being far from the pressure detecting FBG 251 when attached to the regulating member 280 or interfering with other parts during wiring, The FBG 252 may be attached to the pedestal portion 230.
The optical fiber 250 having the FBGs 251 and 252 has been described. However, the pressure detection FBG 251 and the temperature correction FBG 252 may be used as two separate optical fibers 250.
Further, the FBG 252 for temperature correction may not be used.

Further, in the second to fifth embodiments, the FBG 251 is integrally attached so as to be covered with an adhesive. However, when the FBG 251 is subjected to a tensile force as a strain to measure the pressure, the FBG 251 is measured. The FBG 251 itself may not be attached.
For example, in the fourth embodiment, when the FBG 251 is attached to the mounting base 215 side of the spring portion 264 and the FBG 251 is subjected to strain, that is, compressive force is applied to measure the pressure, the FBG 251 is attached so as to cover the entire FBG 251. That is, when the compressive force is applied, the optical fiber 250 may sag and may not be able to measure pressure with high accuracy. Therefore, the optical fiber 250 is attached so as to cover the sag.

In the second to fifth embodiments, when an optical fiber 250 provided with a plurality of FBGs 251 is used and attached so that two FBGs 251 are located at corresponding positions on both sides of the spring portion 264, more accurate measurement can be performed. Therefore, it is preferable.
Specifically, for example, as shown in FIG. 20, the surface of the optical fiber 250 is placed on the surface opposite to the surface on which the FGB 251 is attached on the surface opposite to the surface on which the FBG 251 is attached. Another FBG 251 provided at another position is attached. In the configuration shown in FIG. 20, when measuring the spray pressure of the spray 5, a tensile force acts on the FBG 251 located on the pressure transmission part 222 side, and a compressive force acts on the FBG 251 located on the mounting base part 215 side. . For this reason, the difference in the amount of elastic deformation between the two FBGs 251 is almost double the amount of elastic change in the fourth embodiment. Therefore, even when the amount of elastic deformation is small, the pressure can be accurately measured.

In 3rd Embodiment, although FBG251 was attached and demonstrated to the spring part 264 provided in series in the pressure receiving plate part 263 in the 1st spring member 260, it is not this limitation.
For example, as the first spring member of the present invention, a link mechanism constituted by the first spring member 260 and the pedestal portion 230 is used, and the spring of the pedestal portion 230 is like the spring portion 264 that is the holding portion of the third embodiment. Even if the plate portion 234 is formed to be bent and the FBG 251 is attached to the bent spring plate portion 234, the same effect can be obtained.

In the fifth embodiment, the spring portion 264 that is a pair of holding portions is provided. However, for example, a plurality of spring portions 264 may be provided radially and attached to the housing 210.
As described above, the number of the spring portions 264 may be set according to the pressure applied to the pressure transmitting portion 222, and various applications can be handled with a simple design change, and versatility can be improved.

  In addition, the specific configuration and form in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

  INDUSTRIAL APPLICABILITY The present invention can be used for detection of a spraying state of a spray that disperses and disperses a liquid or two fluids in which a liquid and a gas are mixed in a continuous casting facility, a steel plate cooling device, and the like.

  DESCRIPTION OF SYMBOLS 5 ... Spray, 200 ... Spray pressure measuring device, 210 ... Housing | casing, 220 ... Pressure-receiving part, 230 ... Base part, 233 ... Mounting plate part as an intermediate part, 234 ... Leaf spring part, 235 ... Mounting fixation as an edge part Plate part: 250 ... Optical fiber, 251 ... Fiber Bragg grating (FBG) for pressure detection, 252 ... Fiber Bragg grating (FBG) for temperature correction, 260 ... First spring member, 263 ... Pressure receiving plate part as a central part, 264 ... Spring portion that can function as a holding portion, 265 ... Connection plate portion as a holding portion, 269 ... Mounting fixing portion as a fixing portion, 270 ... Second spring member, 280 ... Restricting member, 286 ... Grease, 290 ... Holding Deformed leaf spring as part

Claims (16)

A spray pressure measuring device for measuring a spray pressure of a spray that disperses and disperses two liquids, or a mixture of liquid and gas,
A housing,
A pressure receiving portion that is provided in the housing and is displaced according to the spraying pressure of the spray;
An optical fiber having a fiber Bragg grating disposed in the housing;
A first spring member that holds the optical fiber in the housing and applies strain to the optical fiber by elastic deformation;
A second spring member provided on the first spring member, formed to have a smaller spring constant than the first spring member, and elastically deforming in response to the displacement of the pressure receiving portion to elastically deform the first spring member;
A spray pressure measuring device comprising: The spray pressure measuring device according to claim 1,
The first spring member is a leaf spring having a central portion facing the fiber Bragg grating and a pair of holding portions that are connected to the central portion and hold both ends of the optical fiber,
Said 2nd spring member is a leaf | plate spring provided in the center part of said 1st spring member. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to claim 2,
A spray pressure measuring device comprising a leaf spring-shaped pedestal portion having an intermediate portion mounted in the housing and an end portion to which the holding portions of the first spring members are respectively mounted. The spray pressure measuring device according to claim 1,
The first spring member is a leaf spring having a central portion and a holding portion connected to the central portion to hold the optical fiber,
Said 2nd spring member is a leaf | plate spring provided in the center part of said 1st spring member. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to claim 4,
The first spring member includes a plate spring-like pedestal portion having an intermediate portion attached to the housing and end portions to which the holding portions of the first spring member are respectively attached. measuring device. The spray pressure measuring device according to claim 5,
The first spring member is a leaf spring-shaped holding portion attached to the pedestal portion so as to bend from the central portion, and a leaf spring-like spring plate provided in a state curved from the intermediate portion of the pedestal portion. And at least one of
The said spring board part can hold | maintain the said optical fiber while the said holding | maintenance part is attached. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to claim 4 or 5, wherein
The first spring member is provided with a pair of holding portions extending in opposite directions at the center portion, and both end portions are held between the tips of the pair of holding portions, and the middle portion is longitudinally provided. A spray pressure characterized by having a leaf spring-like deformed leaf spring portion having a curved portion that curves, and holding the optical fiber by positioning the fiber Bragg grating on the curved portion of the deformed leaf spring portion. measuring device. The spray pressure measuring device according to claim 7,
The spray pressure measuring device, wherein the bending portion is bent so as to protrude to a side opposite to a direction facing the central portion. The spray pressure measuring device according to claim 4,
The holding part of the first spring member is provided with a fixing part attached to the inside of the casing at an end opposite to the central part. The spray pressure measuring device according to claim 9,
The said holding | maintenance part is each provided in the said center part in the state extended in the opposite direction. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to any one of claims 7 to 10,
The spray pressure measuring device, wherein the optical fiber is integrally attached with at least the fiber Bragg grating covered with an adhesive. The spray pressure measuring device according to any one of claims 7 to 11,
The said optical fiber is provided with two or more said fiber Bragg gratings, The said fiber Bragg grating is located and hold | maintained in the position corresponding to both surfaces of a said 1st spring member. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to any one of claims 1 to 12,
A spray pressure measuring device comprising: a regulating member that regulates elastic deformation of the second spring member in a predetermined amount or more according to a displacement of the pressure receiving unit in a predetermined amount or more. The spray pressure measuring device according to claim 13,
The said regulating member regulates the elastic deformation more than predetermined of said 2nd spring member by contact | abutting to the said pressure receiving part or said 2nd spring member. The spray pressure measuring apparatus characterized by the above-mentioned. The spray pressure measuring device according to claim 14,
The spray pressure measuring device, wherein the regulating member is coated with grease on a portion where the pressure receiving portion or the second spring member abuts. The spray pressure measuring device according to any one of claims 1 to 15,
A spray pressure measuring device, comprising a fiber Bragg grating that is disposed in the vicinity of the optical fiber Bragg grating and detects temperature.

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