JP6535604B2 - Measuring device and manufacturing method of measuring device - Google Patents

Description

  The present invention relates to a measuring device and a method of manufacturing the measuring device.

  Conventionally, as a flow sensor for detecting a change in flow rate of fluid, a flow sensor for liquid described in Patent Document 1 has been known. The flow sensor has a semiconductor module in which two temperature sensors and a heat source are respectively provided on the upstream and downstream sides of the fluid flow. The flow sensor includes a pipe (pipe) guiding the liquid, and the semiconductor module (sensor) is provided on the outer surface of the pipe via an adhesive such as a heat conductive paste, and the two temperature sensors and the heat source are the outer surface of the pipe And in thermal contact (FIGS. 1 to 3 of Patent Document 1). The structure of such a flow sensor is adopted when the fluid is not desired to be in contact with a material other than the pipe, or when the semiconductor module is larger than the inner diameter of the pipe and the semiconductor module can not be disposed inside the pipe. .

Japanese Patent Publication No. 2003-532099

  In the flow sensor of Patent Document 1, the semiconductor module is bonded to the outer wall of the pipe. Here, the thickness of the pipe, which is the distance between the outer peripheral surface and the inner peripheral surface of the pipe, greatly affects the sensor sensitivity. Generally, the thicker the pipe, the lower the sensor sensitivity, which may make it impossible to measure the flow rate of the fluid.

  In order to prevent the decrease in the sensitivity of the sensor as described above, it is conceivable to process the thickness of the pipe thin by grinding the outer peripheral surface of the pipe on which the semiconductor module is disposed. However, this thin wall processing is expensive.

  Further, when mechanically processing the thickness of the pipe at the arrangement position of the semiconductor module, there is a possibility that the pipe strength may be deteriorated by damaging the processed surface of the pipe, which may affect the sensor characteristics. Thus, it is not easy to manufacture a flow sensor that can accurately measure the flow rate of fluid by mechanically adjusting the thickness of the pipe. Similar problems can arise with measuring devices other than flow sensors where the sensor is fixed to the pipe.

  Therefore, an object of the present invention is to provide a measuring device capable of maintaining the strength of a tubular member and accurately measuring the flow rate of a fluid, which can be manufactured at low cost.

  In order to solve the above-mentioned subject, the measuring device concerning one side of the present invention has a tubular member in which the 2nd axial center of inner skin is eccentrically parallel to the 1st axis of outer skin, and the outer periphery of a tubular member And a sensor fixed on the surface, wherein in the cross section of the tubular member, the length from the portion where the sensor contacts the tubular member to the second axis is shorter than the length to the first axis.

  In the measurement apparatus, the sensor may be fixed to a portion where the cross-sectional thickness of the tubular member is the thinnest.

  In the above measuring apparatus, a first intersection where a straight line extending from the second axis toward the outer peripheral surface and the inner peripheral surface crosses the inner peripheral surface and a second intersection where the straight line intersects the outer peripheral surface in the cross section of the tubular member And may be fixed at the second intersection when the distance between

  In the above measuring apparatus, the tubular member may be a glass capillary.

  In the above measuring device, a sensor may measure the flow velocity of the fluid flowing inside the tubular member.

  In the above measuring device, a sensor may measure the flow rate of the fluid flowing inside the tubular member.

  In order to solve the above-mentioned subject, the manufacturing method of the measuring device concerning one side of the present invention is on the outer surface of the tubular member which the 2nd axial center of an inner peripheral surface eccentrically parallels to the 1st axial center of an outer peripheral surface. And fixing the sensor to the cross section of the tubular member, the length from the portion where the sensor contacts the tubular member to the second axis is shorter than the length to the first axis.

  The method of manufacturing the measuring device further includes the step of manufacturing a tubular member, and the step of manufacturing the tubular member is a step of drawing a base material in which the axial center of the inner peripheral surface is eccentric in parallel to the axial center of the outer peripheral surface The tubular member may be manufactured.

  In the method of manufacturing the measurement apparatus, the sensor may be fixed to a portion where the cross-sectional thickness of the tubular member is the smallest.

  In the manufacturing method of the above-mentioned measuring device, in the section of the tubular member, a straight line extending from the second axis toward the outer peripheral surface and the inner peripheral surface intersects the inner peripheral surface and a straight line intersects the outer peripheral surface. It may be fixed to the second intersection when the distance to the second intersection is the shortest.

  In the method of manufacturing the measuring apparatus, the tubular member may be a glass capillary.

  In the method of manufacturing the measurement device, a sensor may measure the flow velocity of the fluid flowing inside the tubular member.

  In the method of manufacturing the measuring device, the sensor may measure the flow rate of the fluid flowing inside the tubular member.

  According to the present invention, a measuring device capable of maintaining the strength of a tubular member and accurately measuring the flow rate of fluid, which can be manufactured at low cost, can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows the structural example of the flowmeter which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows the structural example of the flowmeter which concerns on embodiment of this invention. It is a perspective view showing an example of composition of a flow sensor concerning an embodiment of the present invention. It is sectional drawing seen from the IV-IV direction of FIG. 3 of the flow sensor which concerns on embodiment of this invention. It is an enlarged view of the schematic sectional drawing which shows the structural example of the flow meter which concerns on embodiment of this invention. It is a sectional view showing a manufacturing process of a flowmeter concerning an embodiment of the present invention. It is a sectional view showing a manufacturing process of a flowmeter concerning an embodiment of the present invention. It is a sectional view showing a manufacturing process of a flowmeter concerning an embodiment of the present invention. It is an enlarged view of the schematic sectional drawing which shows the structural example of the flow meter which concerns on embodiment of this invention. It is an enlarged view of the schematic sectional drawing which shows the structural example of the flow meter which concerns on embodiment of this invention. It is an enlarged view of the schematic sectional drawing which shows the structural example of the flow meter which concerns on embodiment of this invention. It is a bottom view showing an example of composition of a flow meter concerning an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are schematic and do not necessarily match the actual dimensions, ratios, etc. There may be parts where the dimensional relationships and proportions differ among the drawings.

(Constitution)
The flow meter, which is an example of the measuring apparatus according to the embodiment of the present invention shown in FIGS. 1 and 2, is a pipe 11 and a sensor attached to the outer wall of the pipe 11 for measuring the flow rate of fluid flowing in the pipe 11. And a flow sensor 51. 1 and 2 are cross-sectional views of the flow meter cut in the direction perpendicular to the extending direction of the pipe 11.

  The pipe 11 (tubular member) is a tubular member which allows fluid to pass therethrough, and the axial center S2 (second axial center) of the inner peripheral surface IP is parallel to the axial center S1 (first axial center) of the outer peripheral surface OP. It is configured to be eccentric. The pipe 11 has, for example, an appropriate inner diameter corresponding to the flow rate of the fluid, a wall thickness capable of withstanding the pressure of the fluid, and an optimum length, which are determined according to the use conditions. The outer diameter of the pipe 11 is, for example, several mm. The pipe 11 is made of, for example, a material such as glass, and may be made as, for example, a glass capillary.

  The flow sensor 51 (sensor) is a measuring unit for measuring at least one of the flow velocity and the flow rate of the fluid flowing in the pipe 11. The flow sensor 51 is fixed on the outer peripheral surface of the pipe 11. For example, in the cross section of the pipe 11, the length dy from the portion P where the flow sensor 51 contacts the pipe 11 to the axial center S2 (second axial center) of the inner peripheral surface IP is the axial center S1 of the outer peripheral surface OP (first The flow sensor 51 is fixed on the outer peripheral surface of the pipe 11 so as to be shorter than the length dx up to the (axial center). Although FIG. 1 illustrates an example in which the flow sensor 51 is fixed to a portion where the thickness in the cross-sectional direction of the pipe 11 is the smallest, the flow sensor 51 does not necessarily have the largest thickness in the cross-sectional direction of the pipe 11 The flow sensor 51 does not have to be fixed to the thinned portion, and as shown in FIG. 2, the flow sensor 51 may be fixed to the outer peripheral surface of the pipe 11 so that the length dy is shorter than the length dx.

  The flow sensor 51 further includes a substrate 101 provided with the cavity 102 and an insulating film 103 covering the substrate 101. The insulating film 103 includes the sensor unit 100 and the electrical connection unit 109, and the portion covering the cavity 102 forms a heat insulating diaphragm. The flow sensor 51 is manufactured, for example, by backside etching in which the cavity 102 is formed from the lower side of the substrate 101. The specific configuration of the flow sensor 51 will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a perspective view showing a configuration example of a flow sensor according to an embodiment of the present invention. FIG. 4 is a cross-sectional view of the flow sensor according to the embodiment of the present invention as viewed from the IV-IV direction of FIG. As shown in FIGS. 3 and 4, the flow sensor 51 exemplarily includes a substrate 101 provided with a cavity 102 (FIG. 4), and an insulating film 103 disposed on the substrate 101 so as to cover the cavity 102. The sensor unit 100 is provided on the insulating film 103, the ambient temperature sensor 107, and the electrical connection unit 109 that outputs an electrical signal corresponding to the physical quantity detected by the sensor unit 100.

  The sensor unit 100 is, for example, a temperature detection unit configured to include the heater 104 provided in the insulating film 103 and the temperature measuring resistance elements 105 and 106. The sensor unit 100 may be disposed, for example, on the insulating film 103 of the flow sensor 51, and the sensor unit 100 may be configured to protrude upward from the insulating film 103 or be embedded in the insulating film 103. It may be configured. The sensor unit 100 may be configured to include an ambient temperature sensor 107, which will be described later, in addition to the heater 104 and the temperature measuring resistance elements 105 and 106.

  The ambient temperature sensor 107 measures the temperature of the fluid flowing through the pipe 11. The heater 104 is disposed substantially at the center of the insulating film 103 covering the cavity 102, and heats the fluid flowing through the pipe 11 so as to be a constant temperature higher than the temperature measured by the ambient temperature sensor 107.

As a material of the substrate 101, for example, silicon (Si), glass, ceramic or the like can be used. Substrate 101 may, for example, may be configured as a FPC (F lexible p rinted c ircuits ). As a material of the insulating film 103, silicon oxide (SiO ₂ ), silicon nitride (SiN) or the like can be used. In addition, platinum (Pt) or the like can be used as a material of each of the heater 104, the temperature measuring resistive element 105, the temperature measuring resistive element 106, and the ambient temperature sensor 107.

  The electrical connection unit 109 is connected to the various resistance elements including the heater 104, the temperature measuring resistance element 105, and the temperature measuring resistance element 106, and is a means for outputting information on the electrical resistance of each resistance element. For example, as shown in FIG. 2, the electrical connection portion 109 is disposed in the vicinity of a corner of the substrate 101 in a diagonal relation, and the electrical connection portion 109 is used for the electrical resistance of the heater 104, the temperature measuring resistance element 105, and the temperature measuring resistance element 106. A corresponding electrical signal is taken out via a wire or the like (not shown) and output to a flow rate measuring unit (not shown). For example, the electrical connection portion 109 may be disposed in the insulating film 103, and the sensor portion 100 may be configured to protrude upward from the insulating film 103, or may be configured to be embedded in the insulating film 103. It is also good.

  FIG. 5 is an enlarged view of a schematic cross-sectional view showing a configuration example of a flowmeter according to an embodiment of the present invention. In particular, FIG. 5 is a cross-sectional view seen from the IV-IV direction of FIG. 2 in a flow meter configured such that the piping is fixed along the center line C of the flow sensor 51 of FIG. 3. That is, FIG. 5 is a cross-sectional view of the case where the flow meter including the pipe and the flow sensor attached to the outer peripheral surface of the pipe is cut along the axial center of the pipe. In addition, FIG. 5 is the schematic sectional drawing which expanded the part to which piping and the flow sensor are being fixed.

  As shown in FIG. 5, when the sensor unit 100 of the flow sensor 51 is thermally connected to the pipe 11, the heat of the heater 104 of the sensor unit 100 is propagated to the fluid in the pipe 11 as shown by the arrow A1. Do. Next, the heat of the fluid changed by the heat transmitted from the heater 104 propagates in the direction to the temperature measuring resistive element 105 shown by the arrow A2 and in the direction to the temperature measuring resistive element 106 shown by the arrow A3. The heat propagation in the direction of the arrow A1 and the propagation of heat in the directions of the arrows A2 and A3 are referred to as heat transfer in both directions. When the fluid in the pipe 11 flows from the upstream side to the downstream side, the heat applied by the heater 104 is carried in the downstream direction (conveyance effect). Therefore, the temperature of the temperature measuring resistive element 106 becomes higher than the temperature of the temperature measuring resistive element 105, and a difference occurs between the electric resistance of the temperature measuring resistive element 105 and the electric resistance of the temperature measuring resistive element 106. It is known that the difference in the electrical resistance is correlated with the velocity and flow rate of the fluid flowing in the pipe 11. For this reason, based on the difference between the electrical resistance of the temperature measuring resistive element 105 and the electrical resistance of the temperature measuring resistive element 106, it is possible to measure (calculate) the speed and the flow rate of the fluid flowing in the pipe 11.

  Here, in the cross section of the pipe 11, the length dy from the portion P where the flow sensor 51 contacts the pipe 11 to the axial center S2 (second axial center) of the inner circumferential surface IP is the axial center S1 of the outer circumferential surface OP ( By fixing the flow sensor 51 on the outer peripheral surface of the pipe 11 so as to be shorter than the length dx up to the first axis), the heat conduction between the flow sensor 51 and the fluid in the pipe 11 Will be better. Therefore, it becomes possible to accurately measure the velocity and flow rate of the fluid flowing in the piping 11.

(Manufacturing process)
The manufacturing process of the flowmeter according to the embodiment of the present invention will be described using FIGS. 6 to 11. 6 to 8 are sectional views showing manufacturing steps of the flowmeter according to the embodiment of the present invention. In particular, FIG. 6 is a view showing a pipe base material for manufacturing a pipe. FIG. 7 is a view showing a pipe after drawing processing of a pipe base material. FIG. 8 is a diagram showing a flow meter having a flow sensor fixed to the pipe. FIGS. 9 to 11 are enlarged views of cross-sectional views in the case where the flow meter including the pipe and the flow sensor attached to the outer wall of the pipe is cut perpendicularly to the axial center of the pipe.

The flowmeter according to the embodiment of the present invention is manufactured through the following steps.
(Step 1)
First, as shown in FIG. 6, a perforated pipe base material 10 (base material) is formed in which the axial center Sm of the inner peripheral surface IPm is eccentric in parallel to the axial center Sn of the outer peripheral surface OPn. The outer diameter of the piping base material 10 is 50 mm, for example. The piping base material 10 is comprised with materials, such as glass, similarly to piping, for example.

  In step 1, the process 1 is omitted by delivering the piping base material 10 in which the axial center Sm of the inner peripheral surface IPm is eccentric in parallel to the axial center Sn of the outer peripheral surface OPn in advance. May be implemented.

(Step 2)
As shown in FIG. 7, the pipe 11 (tubular member) in which the axial center S2 (second axial center) of the inner circumferential surface IP is eccentric in parallel to the axial center S1 (first axial center) of the outer circumferential surface OP is manufactured. Do. For example, the piping base material 10 in which the axial center Sm of the inner peripheral surface IP is eccentrically parallel to the axial center Sn of the outer peripheral surface OP shown in FIG.

  Specifically, in the electric furnace, after softening the piping base material 10 at a temperature higher by several hundred degrees C. than the softening point (for example, several thousand degrees C.) of the piping base material 10, the softened piping base material 10 is drawn By doing this, the pipe 11 having an outer diameter of, for example, several mm is manufactured. In addition, in order to obtain the piping 11 of a desired outer diameter and the extending | stretching direction length from the piping base material 10, it can be extending | stretched uniformly using optimal extending | stretching temperature, extending | stretching speed, etc.

(Step 3)
As shown in FIG. 8, the flow sensor 51 (sensor) is fixed on the outer peripheral surface OP of the pipe 11.

  As described above, the flow sensor 51 is fixed to the portion where the thickness in the cross-sectional direction of the pipe 11 is the thinnest. For example, as shown in FIG. 9, the flow sensor 51 is a pipe which is perpendicular to the axis S1 (first axis) of the outer peripheral surface of the pipe 11 and the axis S2 (second axis) of the inner peripheral surface. A cross point P1 (first intersection) at which a straight line L1 extending from the axial center S2 toward the outer circumferential surface OP and the inner circumferential surface IP of the pipe 11 intersects the inner circumferential surface IP and the straight line L1 with the outer circumferential surface OP It is fixed to P2 (second intersection) in the case where the distance to the crossing intersection P2 (second intersection) is the shortest.

  On the other hand, as shown in FIG. 10 as a comparative example, the flow sensor 51 is fixed to a portion where the thickness in the cross-sectional direction of the pipe 11 is the largest. For example, as shown in FIG. 10, the flow sensor 51 is a pipe which is perpendicular to the axial center S1 (first axial center) of the outer peripheral surface of the pipe 11 and the axial center S2 (second axial center) of the inner peripheral surface. An intersection point P1 at which the straight line L1 extending from the axial center S2 toward the outer peripheral surface OP and the inner peripheral surface IP of the pipe 11 intersects the inner peripheral surface IP and an intersection point P2 at which the straight line L1 intersects the outer peripheral surface OP Between the flow sensor 51 and the fluid in the pipe 11 because the thickness in the cross-sectional direction of the pipe 11 becomes larger at P4 where the flow sensor 51 is fixed. Heat conduction may be poor, and the flow rate of the fluid may not be measured accurately. Therefore, as shown in FIG. 9, the flow sensor 51 is preferably fixed to the intersection P2.

  The thickness of the pipe 11 which is the distance between the outer peripheral surface OP of the pipe 11 and the inner peripheral surface IP is configured to be thin (for example, several tens of μm) to such an extent that the heat conduction hardly occurs.

  The method of fixing the flow sensor 51 to the outer peripheral surface of the pipe 11 includes at least the following method.

  For example, there is a method of separately manufacturing the flow sensor 51 and installing and fixing the manufactured flow sensor 51 on the outer peripheral surface of the pipe 11. Specifically, a thermally conductive adhesive (not shown) is attached to cover at least the sensor unit 100 disposed on the substrate 101 of the flow sensor 51, and the thermally conductive adhesive is interposed on the substrate 101. The disposed sensor unit 100 is installed on the outer peripheral surface of the pipe 11, and the heat conductive adhesive is cured.

  A thermally conductive adhesive may be attached to cover only the surface of the sensor unit 100. In order to fix the flow sensor 51 and the pipe 11 more firmly, the heat conductive adhesive is attached so as to cover only the surface of the sensor unit 100, and the adhesive leaks onto the insulating film 103 on the substrate 101. A further thermally conductive adhesive may be attached. Furthermore, the heat conductive adhesive does not have to cover all of the sensor unit 100, and the heat transmitted from the flow sensor 51 to the fluid through the wall of the pipe 11 and the flow from the fluid through the wall of the pipe 11 The sensor unit 100 may be covered to such an extent that the heat transmitted to the sensor 51 can be efficiently transmitted.

  There is no particular limitation on the method of curing the thermally conductive adhesive. For example, as a method of curing the heat conductive adhesive, there are curing methods by light irradiation, curing methods by heating, and the like, but the method is not limited thereto. For example, in the case where the thermally conductive adhesive cures spontaneously, the thermally conductive adhesive may be attached and then allowed to cure for a predetermined period of time. In addition, when the adhesive force of a heat conductive adhesive is low, you may use the attachment (not shown) for fixing the flow sensor 51 firmly by the piping 11, for example.

  The thermally conductive adhesive includes, for example, a paste containing metal particles such as silver, copper, gold, and aluminum. The said paste contains the material obtained by mixing a conductive filler and binder resin, for example. The conductive filler includes, for example, metal fine powder such as silver, copper, iron, nickel and the like, ceramic particles and carbon black. Further, the binder resin includes resins such as epoxy resin, polyester resin, urethane resin, phenol resin and imide resin.

  As another method, there is a method of directly forming and fixing the constituent elements of the flow sensor 51 by performing a predetermined patterning method on the outer peripheral surface of the pipe 11.

FIG. 11 is an enlarged view of a schematic cross-sectional view showing a configuration example of a flowmeter according to an embodiment of the present invention. FIG. 12 is a bottom view showing a configuration example of a flowmeter according to an embodiment of the present invention. As shown in FIGS. 11 and 12, the sensor unit 100 made of platinum (Pt) or the like, the ambient temperature sensor 107, and the electrical connection unit 109 are formed by, for example, a thin film forming method such as evaporation or sputtering, lithography nano It is formed on the outer peripheral surface of the pipe 11 using a patterning method or the like. Further, in order to protect the surfaces of the sensor unit 100 and the ambient temperature sensor 109, a protective film 110 containing silicon nitride (SiN), silicon oxide (SiO ₂ ), fluorine resin, or the like is formed in the protective film formation region 110R. Also good. Each of the sensor unit 100 and the ambient temperature sensor 109 is connected to each electrical connection unit 109 using a wire or the like.

  According to the present embodiment, in the cross section of the pipe 11, the flow sensor 51 has a length dy from the portion P where the flow sensor 51 contacts the pipe 11 to the axial center S2 (second axial center) of the inner circumferential surface IP. It fixes on the outer peripheral surface of the piping 11 so that it may become shorter than length dx to axial center S1 (1st axial center) of outer peripheral surface OP. Therefore, heat conduction between the flow sensor 51 and the fluid in the pipe 11 is improved. Therefore, it becomes possible to accurately measure the velocity and flow rate of the fluid flowing in the piping 11. Since the heat conduction between the flow sensor 51 and the fluid in the pipe 11 is improved, it is not necessary to thin the outer peripheral surface of the pipe 11 by grinding or the like. Therefore, the reduction in strength due to machining surface damage does not occur, and manufacturing can be performed at low cost.

(Other embodiments)
The embodiments described above are for the purpose of facilitating the understanding of the present invention, and are not to be construed as limiting the present invention. In addition, the embodiments described above are merely examples, and there is no intention to exclude the application of various modifications and techniques not explicitly stated above. That is, the present invention can be implemented with various modifications (such as combining the embodiments) without departing from the scope of the invention.

  In each of the above embodiments, the flow meter as the measuring device and the flow sensor as the sensor have been described as an example, but the invention is not limited thereto, and it may be a measuring device configured by installing the sensor on the outer wall of the pipe For example, a calorimeter as a measuring device, a heat quantity sensor as a sensor may be used, or a thermometer as a measuring device, a temperature sensor as a sensor.

DESCRIPTION OF SYMBOLS 1 Flow meter 10 Piping base material 11 Piping 51 Flow sensor 100 Sensor part 101 Substrate 102 Cavity 103 Insulating film 104 Heater 105, 106 Temperature measuring resistance element 107 Ambient temperature sensor 109 Electrical connection part

Claims (13)

A tubular member in which the second axial center of the inner circumferential surface is eccentrically parallel to the first axial center of the outer circumferential surface;
A sensor fixed on the outer peripheral surface of the tubular member;
Equipped with
In the cross section of the tubular member, the length from the portion where the sensor contacts the tubular member to the second axis is shorter than the length to the first axis.
measuring device.   The measuring device according to claim 1, wherein the sensor is fixed to a portion where the cross-sectional thickness of the tubular member is the thinnest. The sensor
A first intersection where a straight line extending from the second axis toward the outer peripheral surface and the inner peripheral surface crosses the inner peripheral surface and a second intersection where the straight line intersects the outer peripheral surface in the cross section of the tubular member Fixed at the second intersection when the distance of
The measuring device according to claim 1 or 2.   The measuring device according to any one of claims 1 to 3, wherein the tubular member is a glass capillary.   The measuring device according to any one of claims 1 to 4, wherein the sensor measures the flow velocity of the fluid flowing inside the tubular member.   The measuring device according to any one of claims 1 to 5, wherein the sensor measures the flow rate of fluid flowing inside the tubular member. Fixing the sensor on the outer peripheral surface of the tubular member in which the second axial center of the inner peripheral surface is parallel to the first axial center of the outer peripheral surface,
In the cross section of the tubular member, the length from the portion where the sensor contacts the tubular member to the second axis is shorter than the length to the first axis.
Method of manufacturing a measuring device. Further comprising the step of manufacturing said tubular member,
In the step of manufacturing the tubular member, the base member in which the axial center of the outer peripheral surface and the axial center of the inner peripheral surface are eccentric in parallel is drawn and manufactured to manufacture the tubular member.
The manufacturing method of the measuring apparatus of Claim 7.   The method for manufacturing a measurement device according to claim 7, wherein the sensor is fixed to a portion where the cross-sectional thickness of the tubular member is the smallest. The sensor
A first intersection where a straight line extending from the second axis toward the outer peripheral surface and the inner peripheral surface crosses the inner peripheral surface and a second intersection where the straight line intersects the outer peripheral surface in the cross section of the tubular member Fixed at the second intersection when the distance of
The manufacturing method of the measuring apparatus of any one of Claims 7-9.   The method of manufacturing a measuring device according to any one of claims 7 to 10, wherein the tubular member is a glass capillary.   The method for manufacturing a measuring device according to any one of claims 7 to 11, wherein the sensor measures the flow velocity of the fluid flowing inside the tubular member.   The method for manufacturing a measurement device according to any one of claims 7 to 12, wherein the sensor measures the flow rate of fluid flowing inside the tubular member.

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