JP5266089B2 - Fluid measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measurement apparatus for properly measuringphysical properties of fluid. <P>SOLUTION: The measurement apparatus 1 is provided and arranged in a flow path pipe 10 for flowing the fluid, and includes: a chamber 5 arranged in an exterior of the flow path pipe 10; an introduction member 20 protruded and arranged in an interior of the flow path pipe 10, and introducing the fluid from the interior of the flow path pipe 10 into the chamber 5; and a microchip 8 arranged in the chamber 5, and measuring the physical properties of the fluid. The introduction member 20 is protruded into the interior of the flow path pipe 10, thereby the fluid in the interior of the flow path pipe 10 can be efficiently introduced into the chamber 5. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a measurement technique, and relates to a fluid measurement device.

  In order to use gas efficiently, it is necessary to monitor and control changes in gas properties due to changes in concentration. For this reason, measuring devices for measuring the physical properties of gas have been proposed (see, for example, Patent Documents 1 and 2). In a measuring apparatus that measures the physical properties of a fluid such as a gas flowing in a flow path, the gas is guided from the flow path to the chamber from the viewpoint of stable measurement, and the physical properties of the gas are measured by a sensor in the chamber.

Japanese Patent Laid-Open No. 11-174010 JP 2007-248220 A

  However, if the fluid is not efficiently guided from the flow path to the chamber, the time required for filling the chamber with gas becomes long, and there is a problem that a change in physical properties of fluid such as gas cannot be measured appropriately. . Therefore, an object of the present invention is to provide a measuring device that can efficiently guide a fluid from a flow path to a chamber and appropriately measure a change in physical properties of the fluid.

  An aspect of the present invention is a measuring device disposed in a flow channel pipe for flowing a fluid, the chamber disposed outside the flow channel tube, and the flow channel tube disposed so as to protrude inside the flow channel tube The gist of the present invention is a measuring device including an introduction member that introduces a fluid into the chamber and a sensor that is disposed in the chamber and measures a physical property of the fluid. According to the measuring apparatus according to the aspect of the present invention, since the introduction member protrudes into the flow channel tube, the fluid inside the flow channel tube can be efficiently introduced into the chamber. Therefore, it becomes possible to appropriately measure the physical properties of the fluid by the sensor.

  ADVANTAGE OF THE INVENTION According to this invention, the measuring apparatus which can measure the physical property of fluid appropriately can be provided.

It is sectional drawing of the measuring apparatus which concerns on the 1st Embodiment of this invention. 1 is a perspective view of a microchip according to a first embodiment of the present invention. It is sectional drawing seen from the III-III direction of FIG. 2 of the microchip which concerns on the 1st Embodiment of this invention. It is a circuit diagram regarding the auxiliary heater which concerns on the 1st Embodiment of this invention. It is a schematic diagram of the central processing unit of the measuring apparatus which concerns on the 1st Embodiment of this invention. It is a graph which shows the relationship between the thermal radiation coefficient of gas and thermal conductivity which concern on the 1st Embodiment of this invention. It is a graph which shows the relationship between the thermal radiation coefficient and density | concentration of gas which concern on the 1st Embodiment of this invention. It is sectional drawing of the measuring apparatus which concerns on the comparative example of the 1st Embodiment of this invention. It is sectional drawing of the measuring apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing seen from the XX direction of FIG. 9 of the introduction member which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the measuring apparatus which concerns on the 3rd Embodiment of this invention. It is sectional drawing seen from the XII-XII direction of FIG. 11 of the introduction member which concerns on the 3rd Embodiment of this invention. It is a graph which shows the time which replacement | exchange of the gas in the chamber based on the Example of this invention requires. It is a schematic diagram of the introduction member which concerns on other embodiment of this invention.

  Embodiments of the present invention will be described below. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

(First embodiment)
As shown in FIG. 1, which is a cross-sectional view, the measuring apparatus 1 according to the first embodiment is disposed in a flow path pipe 10 that flows a fluid such as gas or liquid from the upstream side to the downstream side. The measuring device 1 includes a chamber 5 disposed outside the flow channel tube 10, an introduction member 20 that is disposed so as to protrude into the flow channel tube 10, and introduces a fluid into the chamber 5 from the flow channel tube 10. And a sensor including a microchip 8 that is disposed in the chamber 5 and measures the physical properties of the fluid. Hereinafter, an example in which a gas flows as a “fluid” through the flow channel pipe 10 will be described.

  The channel tube 10 is provided with an opening 11. A cylindrical female screw 12 is arranged on the outer wall of the flow channel tube 10 so as to surround the opening 11. As the female screw 12, an Rc screw (ISO standard) or the like can be used. The chamber 5 is formed integrally with a male screw 13 that fits into the female screw 12. The chamber 5 is fixed to the outside of the flow channel tube 10 by fitting the male screw 13 into the female screw 12. The fitted male screw 13 and female screw 12 constitute a connection portion between the flow path tube 10 and the chamber 5. A through hole 14 is provided in the male screw 13 to allow communication between the inside of the flow path tube 10 and the inside of the chamber 5.

  The introduction member 20 is tubular and has an opening 21 as an introduction port and an opening 22 as a discharge port that are communicated with each other. The opening 21 is provided in a shape in which the distal end of a circular tubular introduction member 20 is cut off obliquely with respect to the axis of the tube. The introduction member 20 is fixed to, for example, the inner wall of the through hole 14 so that the opening 21 faces the upstream side of the flow channel pipe 10. Here, “the opening 21 faces the upstream side of the flow channel pipe 10” does not necessarily mean that the entire opening 21 faces completely upstream. When the introduction member 20 is viewed from the upstream side of the flow channel tube 10, it may be in a state where a part of the opening 21 can be seen. Further, since the outer diameter of the introduction member 20 is smaller than the inner diameter of the through hole 14, there is a space outside the introduction member 20.

  An opening 21 as an introduction port of a tubular introduction member 20 protruding into the flow channel tube 10 is provided so as to be inclined with respect to the gas traveling direction in the flow channel tube 10, and upstream of the flow channel tube 10. Therefore, the inner wall of the introduction member 20 is exposed to the upstream side of the flow channel tube 10. Therefore, a part of the gas flowing from the upstream side in the flow channel pipe 10 enters the opening 21 of the introduction member 20 and collides with the inner wall of the introduction member 20 to change the traveling direction. Therefore, a differential pressure is generated between the upstream side and the downstream side of the introduction member 20, and a part of the gas whose traveling direction is changed flows into the introduction member 20 and is guided to the chamber 5 through the opening 22 as the discharge port. . Further, a part of the gas guided to the chamber 5 passes through the through hole 14 (space outside the introduction member 20) and returns to the inside of the flow channel pipe 10 from the opening 11.

  The opening 21 may not be provided obliquely, but may be provided in parallel with the gas traveling direction. Specifically, the opening 21 may be provided in a shape in which the tip of the circular tubular introduction member 20 is cut off perpendicular to the axis of the tube. Since the introduction member 20 is disposed so as to protrude into the flow channel pipe 10, even if the opening 21 is provided in parallel with the gas traveling direction, a differential pressure is generated between the upstream side and the downstream side of the introduction member 20 and proceeds. A part of the gas whose direction has been changed flows into the introduction member 20.

  When the volume of the chamber 5 is small with respect to the flow rate flowing through the introduction member 20, there is an advantage that the replacement of the fluid in the chamber 5 is fast, but the measurement value of the microchip 8 is easily affected by the flow velocity of the fluid. Arise. On the contrary, when the volume of the chamber 5 is large with respect to the flow rate flowing through the introduction member 20, there is a drawback that the replacement of the fluid in the chamber 5 is slow, but the measured value of the microchip 8 is not easily affected by the flow velocity of the fluid. This produces the advantage. Therefore, it is desirable that the relationship between the flow rate of the fluid flowing through the introduction member 20 and the volume of the chamber 5 be determined in an optimum state by several trials.

  As shown in FIG. 2 which is a perspective view and FIG. 3 which is a cross-sectional view seen from the III-III direction, the microchip 8 disposed in the chamber 5 includes a substrate 60 provided with a cavity 66, and a substrate 60. An insulating film 65 is provided on the cavity 66 so as to cover the cavity 66. The thickness of the substrate 60 is, for example, 0.5 mm. The vertical and horizontal dimensions of the substrate 60 are, for example, about 1.5 mm. A portion of the insulating film 65 covering the cavity 66 forms a heat insulating diaphragm.

  Further, the microchip 8 includes a heating resistor 61 provided on the insulating film 65, and a first resistance temperature measuring element 62 and a second temperature measuring resistance element provided on the insulating film 65 so as to sandwich the heating resistor 61 therebetween. 63 and a gas temperature sensor 64 provided on the substrate 60. The gas temperature sensor 64 also includes an electric resistance element or the like. The heating resistor 61 is disposed at the center of the insulating film 65 that covers the cavity 66. The heating resistor 61 generates heat when power is applied, and heats the gas that is introduced into the chamber 5 shown in FIG. 1 and contacts the heating resistor 61. The gas temperature sensor 64 shown in FIGS. 2 and 3 is provided separately from the heating resistor 61 via the insulating film 65, and detects the gas temperature of the gas introduced into the chamber 5 shown in FIG. .

As a material of the substrate 60 shown in FIGS. 2 and 3, silicon (Si) or the like can be used. As a material of the insulating film 65, silicon oxide (SiO ₂ ) or the like can be used. The cavity 66 is formed by anisotropic etching or the like. Also, platinum (Pt) or the like can be used as the material of the heating resistor 61, the first temperature measuring resistance element 62, the second temperature measuring resistance element 63, and the gas temperature sensor 64. It can be formed.

Here, the resistance value of the heating resistor 61 varies depending on the temperature. The relationship between the heat generation temperature _TH of the heat generation resistor 61 and the resistance value R _H of the heat generation resistor 61 is given by the following equation (1).
R _H = R _STD × [1 + α (T _H -T _STD ) + β (T _H -T _STD ) ² ] (1)
In the formula (1), T _STD represents a standard temperature, for example, 20 ° C. R _STD represents a resistance value measured in advance at the standard temperature T _STD . α represents a first-order resistance temperature coefficient, and β represents a second-order resistance temperature coefficient. Further, the resistance value R _H of the heating resistor 61 is given by the following equation (2) from the driving power P _H of the heating resistor 61 and the energization current I _H of the heating resistor 61.
R _H = P _H / I _H ² (2)
Alternatively, the resistance value R _H of the heating resistor 61 is given by the following equation (3) from the voltage V _H applied to the heating resistor 61 and the energization current I _H of the heating resistor 61.
R _H = V _H / I _H (3)

The heating temperature _TH of the heating resistor 61 is stabilized when the heating resistor 61 and the gas are in thermal equilibrium. The thermally balanced state refers to a state in which the heat generation of the heating resistor 61 and the heat dissipation from the heating resistor 61 to the gas are balanced. In equilibrium, as shown in the following equation (4), the driving power P _H of the heating resistor 61 is divided by the difference between the gas temperature T _O of the heating temperature T _H and the gas of the heating resistor 61, the gas radiation coefficient M _O is obtained. The unit of the heat dissipation coefficient M _O is, for example, W / ° C.
M _O = P _H / (T _H -T _O ) (4)

Energizing current I _H of the heating resistor 61, since the driving power P _H or the voltage V _H can be measured, the heat producing temperature T _H of the heating resistor 61 from the (1) to (3) can be calculated. The gas temperature T _O of the gas can be measured by the gas temperature sensor 64 shown in FIG. Thus, by using the microchip 8 shown in FIGS. 2 and 3, the radiation coefficient M _O of the gas introduced into the chamber 5 as shown in FIG. 1 can be calculated.

The microchip 8 shown in FIGS. 2 and 3 may further include an auxiliary heater that keeps the temperature of the thermally conductive substrate 60 constant. By keeping the temperature of the substrate 60 constant, the temperature of the gas in the vicinity of the microchip 8 approximates the constant temperature of the substrate 60. Therefore, variations in the temperature of the gas is suppressed, it is possible to calculate the radiation coefficient M _O with higher accuracy. An electric resistance element or the like can also be used for the auxiliary heater. The gas temperature sensor 64 may also serve as an auxiliary heater.

As shown in FIG. 4, the gas temperature sensor 64 forms part of a resistance bridge circuit. The resistance bridge circuit includes a resistance element 181 connected in series with the gas temperature sensor 64, and resistance elements 182 and 183 connected in parallel with the gas temperature sensor 64 and the resistance element 181. Here, the resistance value of the gas temperature sensor 64 is Rr, and the fixed resistance values of the resistance elements ₁₈₁ , ₁₈₂ , and ₁₈₃ are R ₁₈₁ , R ₁₈₂ , and R ₁₈₃ , respectively. An operational amplifier 171 is connected to the resistance bridge circuit. When the gas temperature sensor 64 functions as an auxiliary heater, bridge driving is performed so that the bridge voltage V _2a between the resistance element 181 and the gas temperature sensor 64 is equal to the bridge voltage V _2b between the resistance element 182 and the resistance element 183. The voltage V ₁ is feedback controlled. Thereby, the resistance value Rr of the gas temperature sensor 64 becomes constant, and the gas temperature sensor 64 generates heat at a constant temperature as an auxiliary heater.

  As shown in FIG. 1, the microchip 8 is disposed in the chamber 5 via a heat insulating member 18. The heat insulating member 18 makes the temperature of the microchip 8 less susceptible to the temperature fluctuation of the inner wall of the chamber 5. The heat conductivity of the heat insulating member 18 is, for example, 10 W / (m · K) or less. A filter such as a wire mesh may be disposed in the chamber 5 so as to cover the microchip 8. By disposing the filter, it is possible to prevent dust or the like contained in the gas introduced into the chamber 5 from colliding with the microchip 8. Further, by arranging the filter, the flow rate of the gas toward the microchip 8 can be reduced.

The measurement apparatus 1 further includes a measurement unit 30 including a circuit board 100 electrically connected to the microchip 8. The circuit board 100 includes a central processing unit (CPU) 300 schematically shown in FIG. CPU 300 includes a heat dissipation coefficient calculation unit 301. The radiation coefficient calculating portion 301, the (4) As shown in equation, the driving power P _H of the heating resistor 61 of the microchip 8 shown in FIGS. 2 and 3, the heating temperature T _H and the gas of the heating resistor 61 Dividing by the difference from the gas temperature T _O of the gas measured by the temperature sensor 64, the value of the heat radiation coefficient of the gas when in thermal equilibrium with the heating resistor 61 is calculated.

A thermal conductivity storage device 352 is connected to the CPU 300 shown in FIG. Here, FIG. 6 shows the relationship between the heat dissipation coefficient and the thermal conductivity of propane gas when the gas temperature T _O is 0 ° C., 20 ° C., and 40 ° C. As shown in FIG. 6, the heat dissipation coefficient of gas and the thermal conductivity are generally in a proportional relationship. Therefore, the thermal conductivity storage device 352 shown in FIG. 5 stores the correspondence relationship between the heat release coefficient of the gas introduced into the chamber 5 shown in FIG. 1 and the thermal conductivity in advance using an approximate expression or a table.

  CPU 300 shown in FIG. 5 further includes a thermal conductivity calculator 302. The thermal conductivity calculator 302 receives the calculated value of the gas heat dissipation coefficient from the heat dissipation coefficient calculator 301 and reads the correspondence relationship between the heat dissipation coefficient of gas and the thermal conductivity from the thermal conductivity storage device 352. Furthermore, the thermal conductivity calculation unit 302 calculates the thermal conductivity of the gas introduced into the chamber 5 shown in FIG. 1 based on the value of the heat dissipation coefficient of the gas and the correspondence relationship between the heat dissipation coefficient of the gas and the heat conductivity. calculate.

A density storage device 353 is further connected to the CPU 300 shown in FIG. Here, FIG. 7 shows the relationship between the heat dissipation coefficient and the concentration of propane gas when the gas temperature T _O is 0 ° C., 20 ° C., and 40 ° C. As shown in FIG. 7, the gas heat dissipation coefficient and the gas concentration are generally in a proportional relationship. Therefore, the concentration storage device 353 shown in FIG. 5 stores the correspondence relationship between the heat dissipation coefficient and the concentration of the gas introduced into the chamber 5 shown in FIG.

  CPU 300 shown in FIG. 5 further includes a density calculation unit 303. The concentration calculation unit 303 receives the calculated value of the gas heat dissipation coefficient from the heat dissipation coefficient calculation unit 301, and reads the correspondence between the gas heat dissipation coefficient and the concentration from the concentration storage device 353. Further, the concentration calculation unit 303 calculates the concentration of the gas introduced into the chamber 5 shown in FIG. 1 based on the value of the gas heat dissipation coefficient and the correspondence between the gas heat dissipation coefficient and the concentration.

  The measuring apparatus 1 according to the first embodiment described above is easily arranged in the flow channel tube 10 by providing the flow channel tube 10 with the opening 11 and the female screw 12, regardless of the thickness of the flow channel tube 10. Is possible. Therefore, even if the flow channel pipe 10 is an existing pipe, the measuring device 1 can be easily arranged in the flow channel pipe 10. In addition, by introducing a part of the gas flowing inside the flow channel tube 10 into the chamber 5, the physical properties of the gas are measured, so that the size can be reduced as compared with a measuring apparatus that introduces all of the gas into the chamber. Become.

  Further, if the diameters of the female screw 12 and the male screw 13 are reduced in order to reduce the size of the measuring apparatus 1, it is difficult to arrange the microchip 8 in the through hole 14 of the female screw 12. Therefore, the microchip 8 is disposed in the chamber 5 formed integrally with the male screw 13. Here, as shown in FIG. 8, when the introduction member 20 is not provided, the amount of gas flowing from the flow path tube 10 into the chamber 5 is very small. Therefore, there is a problem that it takes time to replace the inside of the chamber 5 with the same gas as the gas flowing through the flow path pipe 10. That is, when the composition of the gas flowing through the flow channel tube 10 changes, it takes time until the microchip 8 detects the change, and the responsiveness is poor.

  On the other hand, according to the first embodiment, as shown in FIG. 1, the opening 21 serving as the introduction port of the tubular introduction member 20 disposed so as to protrude into the flow channel tube 10 is formed by the flow channel tube. It faces 10 upstream. Therefore, the gas flowing through the flow channel pipe 10 is efficiently introduced into the chamber 5. Therefore, it is possible to reduce the time required for replacing the inside of the chamber 5 with the same gas as the gas flowing in the flow channel tube 10, and the responsiveness is good. Further, it is possible to omit an orifice conventionally provided in the flow channel pipe 10 to which the measuring device is attached.

(Second Embodiment)
As shown in FIG. 9 and FIG. 10 which is a cross-sectional view seen from the XX direction, the introduction member 220 of the measuring apparatus 1 according to the second embodiment has a plurality of through holes 25, 26a, 26b, 26c. , 26d, 26e, and 26f are provided in parallel. In the cross section of the cylindrical introduction member 220, the plurality of through holes 26a, 26b, 26c, 26d, 26e, and 26f are provided at regular intervals on the circumference, and the through hole 25 is the center of the circumference. Is provided.

  As shown in FIG. 9, the end portion of the introduction member 220 located so as to protrude into the flow channel tube 10 has a substantially conical shape. The through hole 26a communicates the opening 221a provided on the side surface of the substantially conical end portion of the introduction member 220 and the opening 222a provided on the end portion on the chamber 5 side. The through hole 26d communicates the opening 221d provided on the side surface of the substantially conical end portion of the introduction member 220 and the opening 222d provided on the end portion on the chamber 5 side. Each of the through holes 26b, 26c, 26e, and 26f shown in FIG. 10 also communicates the opening provided on the side surface of the substantially conical end with the opening provided on the other end. Further, the through hole 25 shown in FIG. 9 communicates the opening 223 provided at the apex of the substantially conical end and the opening 224 at the other end.

  Since the plurality of openings other than the opening 223 are provided on the side surfaces of the substantially conical end portions, they are inclined with respect to the gas traveling direction in the flow channel tube 10. Accordingly, a part of the gas flowing from the upstream side in the flow channel pipe 10 enters at least a part of the plurality of openings, collides with the inner wall of the introduction member 220, and changes its traveling direction, and passes through the through-hole to the chamber. 5, and returns to the inside of the flow pipe 10 through the other through-holes from the opening 223 and the opening 221 d.

  In addition, when there is only one opening 21 of the introduction member 20 as shown in FIG. 1, whether or not the opening 21 faces the upstream side due to the screwing condition when using a screw connection as shown in FIG. 1. In some cases, visual confirmation from the outside is difficult. On the other hand, the introduction member 220 shown in FIGS. 9 and 10 has a plurality of openings of at least three or more provided on the side surface of the substantially conical end portion at equal intervals on the circumference. Therefore, even if the introduction member 220 is inserted into the flow channel pipe 10 in any direction, any of the plurality of openings can be directed upstream of the flow channel pipe 10. Here, “directing any of the openings toward the upstream of the flow pipe 10” does not necessarily mean that the entire opening is completely directed upstream. It suffices if at least a part of the opening is visible when the introduction member 220 is viewed from the upstream side of the flow channel tube 10. Although FIG. 9 shows an example in which the introduction member 220 is inserted into the through hole 14 in the male screw 13, the introduction member 220 and the male screw 13 may be integrally formed.

(Third embodiment)
As shown in FIG. 11 and FIG. 12, which is a cross-sectional view seen from the XII-XII direction, the introduction member 320 inserted into the through hole 14 of the male screw 13 of the measuring apparatus 1 according to the third embodiment is A plurality of partition plates 32A, 32B, 32C, and 32D that are arranged radially are provided. The plurality of partition plates 32A, 32B, 32C, and 32D partition the through hole 14 of the male screw 13 into four spaces. Further, the plurality of partition plates 32 </ b> A, 32 </ b> B, 32 </ b> C, 32 </ b> D of the introduction member 320 protrude into the flow channel tube 10.

  A part of the gas flowing from the upstream side in the flow channel pipe 10 collides with at least a part of the plurality of partition plates 32A, 32B, 32C, 32D, the direction of travel is changed, and the male screw partitioned into four 13 is introduced into the chamber 5 through a part of the through holes 14. In addition, by providing at least three or more partition plates, even if the introduction member 320 is inserted into the flow channel pipe 10 in any direction, any one of the partition plates faces the upstream side of the flow channel tube 10. Is possible. 11 shows an example in which the introduction member 320 is inserted into the through hole 14 in the male screw 13, the introduction member 320 and the male screw 13 may be integrally formed.

(Example)
It is necessary to replace the 100% concentration nitrogen (N ₂ ) gas filled in the chamber 5 of the measuring apparatus 1 shown in FIGS. 1, 8, and 11 with a 100% concentration carbon dioxide (CO ₂ ) gas. The result of measuring time is shown in FIG. In FIG. 13, the horizontal axis indicates the flow rate of the gas in the flow path pipe 10, and the vertical axis indicates the time required for replacing the gas filled in the chamber 5. In the case of the measuring apparatus 1 shown in FIG. 8 that does not have an introduction member, the replacement of the gas in the chamber 5 took a long time when the flow rate of the gas in the flow path pipe 10 was 2 m / s or less. Further, even if the flow velocity of the gas in the channel tube 10 is faster than 2 m / s, it took several minutes to replace the gas in the chamber 5. On the other hand, in the case of the measuring apparatus 1 shown in FIGS. 1 and 11, the gas in the chamber 5 can be replaced within 20 seconds even if the flow velocity of the gas in the flow channel pipe 10 is 2 m / s or less. It was possible. Therefore, it has been shown that the gas in the chamber 5 can be efficiently replaced by the introduction member according to the embodiment of the present invention.

(Other embodiments)
Although the present invention has been described by the embodiments as described above, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques should be apparent to those skilled in the art.

  For example, in FIG. 1, although the example which connected the chamber 5 and the flow path pipe 10 using the external thread 13 and the internal thread 12 was demonstrated, the chamber 5 and the flow path pipe 10 were connected using the flange (not shown). Also good. When the male screw 13 and the introduction member 20 are integrated, the direction of the opening 21 of the introduction member 20 differs depending on how much the male screw 13 is rotated and screwed into the female screw 12 (rotation angle), and the opening 21 is directed upstream. There are cases where it is difficult to arrange them in a sparse manner. On the other hand, by using the flange, for example, the chamber 5 and the flow path pipe 10 can be connected with the opening 21 of the introduction member 20 fixed to the chamber 5 facing upstream. That is, one flange is provided at the opening end of the cylindrical portion having the through hole 14 in the measuring apparatus 1, and the other flange is provided at the opening end of the cylindrical portion raised around the opening 11 in the flow channel tube 10. It has been. Each of these flanges is provided with a plurality of bolt holes for fastening in advance. Both flanges are brought into contact with each other so that the positions of the respective bolt holes are matched, and are fastened by bolts and nuts. If the positions of the bolt holes of both flanges are appropriately arranged, the opening 21 can be accurately fixed upstream.

  Alternatively, in FIG. 1, by using a cap nut (not shown) provided around the chamber 5 so as to be rotatable and non-detachable (having a through hole in the center, and the chamber 5 is inserted into the through hole), It is also possible to adopt a structure in which the measuring device 1 and the flow channel tube 10 are coupled. In this case, the male screw 13 and the female screw 12 are not formed on the outer peripheral surface of the cylindrical portion of the measuring apparatus 1 and the inner peripheral surface of the cylindrical portion raised around the opening 11 of the flow channel tube 10, respectively. It is in a fitted state. Then, a male screw is formed on the outer peripheral surface of the cylindrical portion raised around the opening 11 of the flow channel tube 10, a corresponding female screw is formed on the inner peripheral surface of the cap nut, and both are fastened. The measuring device 1 is fixed to the flow channel tube 10. According to this configuration, since the cap nut can be rotated and the both can be fastened while the positional relationship between the measuring device 1 and the flow channel tube 10 is fixed, it is possible to fix the opening 21 in a state where the opening 21 is directed accurately upstream. it can. In addition to the above, various fastening structures that do not cause rotation in the positional relationship between the measuring device 1 and the flow channel tube 10 are known, and can be appropriately employed depending on the application.

  Moreover, as shown in FIG. 14, you may provide the some opening 42a, 42b, 42c of at least 3 or more so that the side wall of the tubular introduction member 420 may go around. Even if the introduction member 420 shown in FIG. 14 is inserted in any direction into the flow channel pipe 10 shown in FIG. 8, any one of the plurality of openings 42 a, 42 b, 42 c faces the upstream side of the flow path pipe 10. To do. Further, since the plurality of openings 42 a, 42 b, 42 c are provided on the side wall of the tubular introduction member 420, the openings 42 a, 42 b, 42 c are perpendicular to the gas traveling direction in the flow channel tube 10. Therefore, the gas can be efficiently taken into the introduction member 420. In addition to the portions that use screw fastening, the cross-sectional shape of the tube, tube, and hole is not limited to a circle. It may be a square tube, a square tube, or a square hole. Thus, it should be understood that the present invention includes various embodiments and the like not described herein.

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 5 Chamber 8 Microchip 10 Channel pipe 11 Opening 14 Through-hole 18 Thermal insulation member 20,220,320 Introduction member 21,221a, 221d, 223 Opening 22,222a, 222d, 224 Opening 25,26a, 26b, 26c , 26d, 26e, 26f Through-hole 30 Measuring unit 32A, 32B, 32C, 32D Partition plate 60 Substrate 61 Heating resistor 62 Temperature measuring element 63 Temperature measuring element 64 Gas temperature sensor 65 Insulating film 66 Cavity 100 Circuit board 171 Operational amplifier 181, 182, 183 Resistance element 301 Heat radiation coefficient calculation unit 302 Thermal conductivity calculation unit 303 Concentration calculation unit 352 Thermal conductivity storage device 353 Concentration storage device

Claims (8)

A measuring device arranged in a flow channel pipe for flowing a fluid,
A chamber disposed outside the channel tube;
Is arranged to protrude into the flow pipe section, said a tubular introduction member for introducing said fluid into the chamber from the flow pipe section, substantially conical end portion located on the flow pipe An introduction member having
Disposed in said chamber, a sensor for measuring the physical properties of the fluid,
Equipped with a,
The chamber is provided with a male screw portion that can be screwed into a female screw opening provided in the flow channel pipe,
The male screw part is provided with a male screw through-hole that allows the inside of the flow channel tube and the inside of the chamber to communicate with each other.
The introduction member protrudes from the inside of the male screw through hole into the flow channel pipe,
In the introduction member, a plurality of through-holes are provided for communicating the inside of the chamber and the inside of the flow channel pipe,
Openings of the plurality of through holes are provided at the apex and side surfaces of the substantially conical end of the introduction member,
On the side surface of the substantially conical end, three or more of the plurality of openings are provided on the circumference at regular intervals,
The fluid that has entered at least one of the plurality of openings from the flow channel tube collides with the inner wall of the through hole of the introduction member to change the traveling direction, and is introduced into the chamber.
measuring device.   A measuring device arranged in a flow channel pipe for flowing a fluid,
  A chamber disposed outside the channel tube;
  A sensor that is disposed in the chamber and that measures physical properties of the fluid introduced into the chamber from the flow path pipe;
  With
  The chamber is provided with a male screw portion that can be screwed into a female screw opening provided in the flow channel pipe,
  The male screw portion is provided with a male screw through hole for communicating the inside of the chamber and the inside of the flow channel tube,
  In the male screw through hole, a plurality of partition plates of at least three or more arranged radially in cross section are arranged,
  The plurality of partition plates are arranged so as to protrude from the through hole into the flow channel pipe,
  The fluid that has collided with the plurality of partition plates inside the channel pipe is changed in the traveling direction, and is introduced into the chamber.
  measuring device. The measuring apparatus according to claim 1, wherein the opening provided on a side surface of the substantially conical end portion of the introduction member is inclined with respect to a traveling direction of the fluid in the flow channel pipe. At least a portion of said opening substantially provided on the side surface of the conical end portion of the introducing member, faces the upstream of the flow pipe, measuring device according to claim 1 or 3. Wherein the fluid is a gas, the measurement apparatus according to any one of claims 1 to 4. The measuring apparatus according to claim 5 , wherein the physical property of the fluid is a heat dissipation coefficient of the gas. The measuring apparatus according to claim 5 , wherein the physical property of the fluid is a thermal conductivity of the gas. The measurement apparatus according to claim 6 , further comprising a concentration calculation unit that calculates the concentration of the gas based on the heat dissipation coefficient.

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