JP2009262015A - Passage forming body equipped with temperature sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem associated with a device for reacting substances in a microspace such as a microdevice wherein accurate measurement of the temperature of a fluid flowing in its passage is required for the purpose of controlling the reaction temperature, and wherein the fluid flow is disturbed if its temperature sensor is disposed in the passage and the temperature in the passage cannot accurately be measured if the temperature sensor is disposed outside the passage. <P>SOLUTION: The passage forming body (1) equipped with a temperature sensor includes a seal metal-fitting (11), a temperature sensor (12) with a temperature measuring part (37) thereof bonded to the seal metal-fitting (11), and a heat-insulation member (13) that covers the seal metal-fitting (11) and the temperature sensor (12), whereby the heat generated in a passage (21) can accurately be detected without disturbing the fluid flow. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a flow path forming body with a temperature sensor.

  A microchemical plant is a production facility that uses mixing, chemical reaction, separation, and the like in a microscale space. And it has many advantages compared with the conventional batch-type plant using a large tank etc. Specifically, the following points are mentioned. First, it is possible to mix a plurality of fluids and perform a chemical reaction with a small amount of sample in a short time. Next, since the equipment is small, if the production technology of the product can be established at the laboratory level, the equipment for mass production can be easily installed by numbering up. It can also be applied to reactions that involve dangers such as explosions, can be quickly adapted to the production of compounds that require high-mix low-volume production, and can easily adjust the production volume to meet demand. A point etc. are mentioned.

In microchemical plants, the reaction rate and the quality of the product can be improved by controlling the reaction temperature of the fluid. In order to control the reaction temperature, it is necessary to accurately measure the temperature of the fluid flowing through the micro flow path that is the reaction path. Several techniques for measuring the temperature of the liquid flowing through the microchannel have already been disclosed. For example, Patent Document 1 discloses a microreactor configured such that a temperature sensor insertion port is provided in a microreaction main body forming a microchannel, and a temperature of the liquid phase is measured by the temperature sensor inserted therein. ing. Patent Document 2 discloses a microchannel device in which a temperature sensor is provided inside the microchannel.
JP 2004-321063 A JP 2006-130599 A

  In the microreactor described in Patent Document 1, since the temperature sensor measures the heat of the reaction solution transmitted through the microreaction main body, there is a problem that the measurement temperature is inaccurate. Moreover, in the microchannel device described in Patent Document 2, since the temperature sensor is provided in the microchannel, the accuracy of temperature measurement is improved.

However, there is a problem that the liquid flow is disturbed by the temperature sensor and the flow is disturbed. In particular, the flow path used in the microchemical plant has a cross-sectional area of several mm ² or less. A thermocouple sensor mainly used as a temperature measuring sensor generally has a diameter of 0.5 mm (a cross-sectional area of 0.785 mm ² ) or more. That is, a thermocouple blocks a considerable part of the cross-sectional area of the flow path.

  Therefore, when a flow in a state where a laminar flow state is maintained is required, there is a possibility that a turbulent flow may occur due to an obstacle of the temperature measurement sensor when the technique of Patent Document 2 is used.

  The present invention has been made in view of such a problem, and is capable of accurately measuring the temperature of the fluid flowing through the flow path and forming a flow path with a temperature sensor that does not cause turbulence in the flow. The purpose is to provide a body.

In order to achieve the above object, the present invention provides:
A seal fitting (11);
A temperature sensor (12) joined to the seal fitting (11);
A temperature sensor-equipped flow path forming body (1) having a heat insulating member (13) covering the seal fitting (11) and the temperature sensor (12) is provided.

  In the flow channel forming body with temperature sensor of the present invention, a flow channel through which a liquid flow flows is formed with a seal fitting, and the temperature sensor is joined to the seal fitting. Therefore, the flow of the fluid flowing through the seal fitting serving as the flow path is not hindered by the temperature measuring unit of the temperature sensor, and the flow is not disturbed.

  Further, the temperature measuring section (37) of the temperature sensor (12) obtains heat from the fluid flowing in the flow path (21) constituted by the seal fitting through the seal fitting. By reducing the thickness of the seal fitting as much as possible, heat conduction can be improved and the temperature of the fluid can be accurately measured. Specifically, if this seal fitting is formed of a nickel alloy (for example, Hastelloy (registered trademark) C276) and its thickness is about 0.35 mm, the structure can withstand use at 10 MPa / 200 ° C.

  In addition, the temperature measuring part (37) is reliably maintained while maintaining high thermal conductivity by joining the metal fitting (11) and the temperature measuring part (37) of the temperature sensor (12) with the silver solder (40). Can be fixed to. In particular, in the present invention, since the temperature sensor is wound around the seal fitting serving as the flow path and joined with the silver brazing, the heat generated inside the seal fitting can be accurately detected by the temperature sensor.

  The temperature sensor (12) has a structure in which a thermocouple element is housed in an inside of a metal sheath via an insulating material, and thus is suitable for application to a micro device. A temperature sensor having this structure is also called a sheath thermocouple type temperature sensor.

  By disposing the heat insulating member (13) with a synthetic resin such as PPS resin or fluorine resin around the seal fitting around which the temperature sensor is wound, the fluid flowing in the flow path (21) is radiated to the outside or from the outside. The effect of gun heat is very little.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the column of the means for solving a claim and a problem shows the correspondence with the specific means as described in embodiment mentioned later.

  According to the flow path forming body with a temperature sensor of the present invention, the temperature of the fluid flowing through the flow path can be accurately measured, and the flow can be prevented from being disturbed.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1A is a partial front sectional view showing the basic configuration of the present invention. FIG.1 (b) is the figure seen from the flow-path opening side.

  The temperature sensor-equipped flow path forming body 1 of the present invention includes a seal fitting 11, a temperature sensor 12, and a heat insulating member 13. Each of these components will be described.

  FIG. 2 shows the seal fitting 11. The seal fitting 11 is a member constituting the flow path 21. Therefore, it is often configured in a cylindrical shape with both ends being open ends. However, it is not limited to this shape, and a hole may be formed in the middle of the cylinder, or one end or both ends may be closed ends. Since various reactions occur in the channel 21, it is preferable to use a material having excellent heat resistance and corrosion resistance and high thermal conductivity.

  Many metals generally satisfy these conditions and can be suitably used. Specifically, an alloy containing nickel as a main component is preferable, and more specifically, a metal such as Hastelloy (registered trademark) steel is preferably used. However, it is not limited to metals, and may be a resin such as a synthetic resin such as polytetrafluoroethylene or an adhesive fluororesin.

  The cross-sectional shape is not particularly limited, and a circular shape, an oval shape, a polygonal shape, or the like can be used as appropriate. However, a circular shape can be preferably used. This is because the heat generated inside is easily transferred to the inner wall evenly.

  The thinner the wall thickness 22 of the seal fitting 11, the easier the heat generated in the flow path is transferred to the temperature sensor. That is, the temperature characteristics are improved. On the other hand, when the thickness 22 is reduced, the strength against the pressure generated in the flow path is reduced. For this reason, it is necessary to select and design the material and wall thickness in a balance between temperature characteristics and pressure resistance. For example, when the above-mentioned Hastelloy (registered trademark) C276 is used to secure pressure resistance up to an internal pressure of 10 MPa / 200 ° C., it is desirable that the wall thickness is about 0.35 mm. Here, “about 0.35 mm” is intended to include a thickness range that can ensure the pressure resistance.

The cross-sectional area of the flow path is preferably 1 mm ^{2 to} 8 mm ² . This is because if the cross-sectional area of the flow path is smaller than 1 mm ² , it becomes as large as the temperature sensor and accurate temperature measurement cannot be performed. Further, if the cross-sectional area of the flow path is larger than 8 mm ^2, it is difficult to instantaneously detect the temperature generated in the flow path outside the seal fitting 11.

  FIG. 3 shows a configuration example of the temperature sensor 12 used in the present invention. This temperature sensor 12 is a sheath thermocouple type temperature sensor. The temperature sensor 12 includes a sheath 31, a thermocouple element 32, and a filling member 33. Moreover, you may provide the adapter 32, the lead wire 35, etc.

  The sheath 31 has a cylindrical shape with one end being a closed end and the other end being an open end. The material is not particularly limited as long as the material has high thermal conductivity. Specifically, copper, iron, nickel, zinc, stainless steel and the like can be suitably used. The size should be small. For example, the diameter is preferably about 0.5 mm. This is because a thinner one has a smaller heat capacity and is preferable for measurement.

  The thermocouple element 32 is formed by joining two strands made of different kinds of metals. Specifically, a thermocouple element in which one end of each of the chromel wire and the alumel wire is joined at a joint point 38 is preferably used. This thermocouple is disposed in the sheath 31.

  As the filler 33, ceramics such as alumina can be used. Filler 33 is used to sufficiently achieve thermal contact between the closed end of sheath 31 and the junction of the thermocouple element and to ensure mechanical retention of the thermocouple element within the sheath. It is filled so as to fill the space between the inner wall and the thermocouple element.

  In the thermocouple element 32, the junction point 38 is arranged at the closed end of the sheath 31, and the terminals of both the strands come out from the open end of the sheath. This terminal enters the adapter and is connected to the lead wire. The lead wire is connected to the measuring instrument 36, and the temperature is measured from the potential difference between the two strands. A resistance temperature detector may be used for the thermocouple element. The thermocouple element 32 measures the temperature by the thermoelectromotive force due to the temperature of the junction point 38. Therefore, the closed end of the sheath 31 on which the joining point is arranged becomes a part for measuring heat. This part is called a temperature measuring unit 37.

  The temperature sensor 12 is required to faithfully measure the temperature of the flow path 21. For that purpose, it is necessary to instantaneously detect the temperature of the seal fitting 11 constituting the flow path and not to be affected by heat from the outside. Therefore, in the flow path forming body 1 with the temperature sensor of the present invention, the temperature sensor 12 is wound around the seal fitting 11 several times, and the sheath including the side temperature portion 37 is joined with a brazing material.

  By doing in this way, the influence of an external heat can be avoided and the effect that it is made to contact a flow path enough thermally can be acquired. Moreover, the temperature generated in the flow path 21 can be instantaneously detected by joining the side temperature portion 37 to the seal fitting 11 with a brazing material.

Here, since the response delay of the temperature sensor is substantially determined by the heat capacity of the temperature sensor, the heat transfer coefficient and the surface area of the surface, it is desirable that the temperature sensor has a minimum allowable outer shape. A 63.2% response, generally called a time constant, is expressed by equation (1).
τ = C / (α · A) (1)
C: Heat capacity of the object Kcal / ° C
α: Average heat transfer coefficient Kcal / (m ² · ° C · s)
A: Surface area of the object m ²

  Specifically, stainless steel was used for the sheath 31 and magnesia powder was used for the filler 33. The time constant of the sheath thermocouple type temperature sensor alone having a diameter of 0.5 mm was 0.23 seconds under the condition of being immersed in boiling water from room temperature.

  Next, the response delay with respect to the fluid temperature of the temperature sensor attached to the flow path forming body is mainly determined by the heat capacity of the temperature sensor and the seal fitting, the heat transfer coefficient and the area of the surface, and the heat transfer coefficient is affected by the flow velocity. The time constant of the flow path forming body temperature sensor in which the sheath thermocouple type temperature sensor having a time constant of 0.23 seconds is wound twice around a seal fitting having an outer diameter of 2.5 mm and a wall thickness of 0.35 mm is a flow rate of 2. It was 2 m / s or more and 0.5 second or less. The measurement conditions are such that water at 60 ° C. is passed through the flow path forming body in the room temperature state.

  Referring to FIG. 1 again, the heat insulating member 13 is preferably made of a synthetic resin such as a PPS resin or a fluororesin. The heat insulating material 13 is provided so as to cover the seal fitting 11 and the temperature sensor 12. The lead wire 35 side of the adapter 34 of the temperature sensor 12 may not be covered with the heat insulating member 13. The heat insulating member is disposed to suppress heat from the surroundings and heat radiation of the thermocouple type temperature sensor in order to accurately measure the heat generated in the flow path.

  Moreover, the brazing material 40 which joins the sealing metal fitting 11 and the temperature sensor 12 can use silver brazing suitably. Silver brazing is a brazing material mainly composed of silver, has a melting point higher than that of solder, but has wettability to stainless steel and nickel alloy, and also has high thermal conductivity. In the case where the seal metal fitting 11 is made of polytetrafluoroethylene, a resin material such as a synthetic resin such as an adhesive fluororesin can be suitably used for the brazing material 40.

  Next, a method for assembling the temperature sensor-equipped flow path forming body 1 including the above-described components will be described.

  Referring to FIG. 4, temperature sensor 12 is wound around the outer periphery of seal fitting 11 and fixed by brazing material 40. In particular, the temperature measuring unit 37 of the temperature sensor 12 is reliably joined to the seal fitting 11 by the brazing material 40. The seal fitting 11 to which the temperature sensor 12 is fixed is housed in a mold, and the whole is molded with resin. In this way, the temperature sensor-attached flow path forming body 1 shown in FIG. 1 is obtained.

  As mentioned above, although embodiment of this invention was described, embodiment disclosed above is an illustration to the last, Comprising: The scope of the present invention is not limited to this embodiment. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

INDUSTRIAL APPLICABILITY The present invention can be suitably used for an apparatus that performs reaction or synthesis in a micro space such as a micro device or a micro plant.

It is a figure which illustrates the composition of the channel formation object with a temperature sensor concerning the present invention. It is a figure which shows a sealing metal fitting. It is a figure which shows a temperature sensor. It is a figure which shows the state which fixed the temperature sensor to the seal metal fitting.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flow path formation body with temperature sensor 11 Seal metal fitting 12 Temperature sensor 13 Heat insulation member 21 Flow path 22 Thickness of seal metal fitting 31 Sheath 32 Thermocouple element 33 Filling member 34 Adapter 35 Lead wire 36 Measuring instrument 37 Temperature measuring part 38 Junction point 40 Brazing material

Claims (8)

A seal fitting (11);
A temperature sensor (12) joined to the seal fitting (11);
A flow path forming body with temperature sensor (1) having a heat insulating member (13) covering the seal fitting (11) and the temperature sensor (12). The temperature sensor (12)
A tubular sheath (31) with one closed end and the other open end;
A thermocouple element (32) having a joint 38 disposed in the sheath (31);
The flow path forming body with a temperature sensor according to claim 1, which is a temperature sensor having a filling member (33) placed in the sheath. The temperature sensor (12) further includes
The flow path forming body with a temperature sensor according to claim 2, further comprising an adapter (34) for connecting a terminal of the thermocouple element and a lead wire. The flow path forming body with a temperature sensor according to any one of claims 1 to 3, wherein a cross-sectional area of the flow path of the seal fitting (11) is 1 mm ^{2 to} 8 mm ² . The flow path forming body with a temperature sensor according to any one of claims 1 to 4, wherein the seal fitting (11) is made of a nickel alloy and has a flow path thickness of 0.35 mm. The temperature sensor (12) is wound around the seal fitting (11), and at least a temperature measuring part (37) of the temperature sensor is joined to the seal fitting (11). A flow path forming body with a temperature sensor according to claim. The flow path molded body with a temperature sensor according to any one of claims 1 to 6, wherein the joining is joined by a brazing material (40). The flow path forming body with a temperature sensor according to claim 7, wherein the brazing material (40) is silver brazing.

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