JP4822054B2 - Heating device for fluid heating tube and method for heating fluid heating tube - Google Patents

Description

  The present invention relates to a fluid heating tube for heating a specimen or other fluid, and a heating method for the fluid heating tube.

  Conventionally, exothermic tubes used as water supply hoses for home water supply, hot water supply, etc. are known. In view of the problem of freezing, there is the following proposal in order to generate heat at a constant temperature over the entire length of the hose (see Patent Document 1).

  That is, as shown in FIG. 5, a cylindrical synthetic resin exothermic tube composed of an inner layer tube 11 and an outer layer tube 12, which does not cross each other between the inner layer tube 11 and the outer layer tube 12. Two bare copper wires 13a and 13b and one heating fiber 14 are embedded, and the bare copper wires 13a and 13b are in contact with the heating fiber 14 at a predetermined interval. As a result, since the heating fiber 14 is in contact with the bare copper wires 13a and 13b at regular intervals, heat is generated from the bare copper wires 13a and 13b by passing an electric current through the bare copper wires 13a and 13b embedded in the exothermic tube. The parallel circuits formed of the fibers 14 are formed at equal intervals, and the entire tube can generate heat at a constant temperature regardless of the length of the tube.

  By the way, the technical field to which the invention belongs is slightly different from the large-diameter exothermic tube as a living material such as water supply and hot water as described above. There is an attempt to create a large life science market such as a diagnostic chip (see Non-Patent Document 1).

  Specifically, in order to raise the temperature of a sample or other fluid to about the body temperature and supply it to the analyzer, development of a pipe (process pipe) that heats a tube through which the fluid flows is brought into contact with a heat source is in progress. .

However, there is a problem that the contact area between the process tube and the heat source (such as a plate-like or string-like heater) is small and cannot be heated uniformly over the entire length.
Japanese Unexamined Patent Publication No. 2004-162827 (pages 2 and 3, FIG. 1) Micro Chemical Process Technology Research Association Homepage, “Business Objectives”, [2004/11/5 Search], Internet <URL: http://www.mcpt.jp/japanese/mission.html>

  Therefore, the present invention is intended to provide a fluid heating tube and a heating method for the fluid heating tube that can heat the fluid more uniformly over the entire length than ever before.

(Invention of Claim 1)
The fluid heating tube heating apparatus according to the present invention is a tube for raising the temperature of a fluid, and at least the outermost surface is formed of a conductive heat generating layer, and conductive heat generation is performed by applying a voltage in a diameter direction of the conductive heat generating layer. The layer generates heat and the fluid is heated. The fluid heating tube heating device is a tube for raising the temperature of the fluid, and the fluid heating tube having an outermost surface at least in the longitudinal direction formed of the conductive heating layer (3) is formed in a spiral shape. The conductive heating layer (3) is heated by applying a voltage in the tube diameter direction by sandwiching the entire tube from the front side and the back side with a pair of electrodes (4, 4) having a spiral shape. The temperature of the fluid in the tube is raised.

  In the fluid heating tube of the present invention, at least the outermost surface is formed of a conductive heat generating layer, and by applying a voltage in the tube diameter direction, the conductive heat generating layer generates heat and the tube is heated. Heating can be performed more efficiently than when a tube is brought into contact with an attached heater / heat source to transfer heat to a fluid.

  For example, the collected analysis specimen (fluid) is introduced into the analytical instrument in a state where it is heated more efficiently and heated from room temperature to about 35 to 37 ° C. in order to bring it close to conditions similar to those in the living body be able to.

Here, the conductive heat generating layer can contain a resin or a substance (for example, carbon or metal powder) having a property of generating heat when conductive. Moreover, when the volume resistivity is set to 10 ⁻⁶ to 10 ⁵ Ω · cm, there is an advantage that the temperature rise can be freely set.
This tube can be carried out with an inner diameter of preferably 8 mm or less, and more preferably 3 mm or less in terms of temperature rise efficiency.

Since the tube is formed in a spiral shape, a long range of the tube can be heated with an electrode having a relatively small area. The tube itself may be composed of a single material made of a conductive heat generating material.
(Invention of Claim 2)
In the present invention, a temperature sensor (S) for detecting the tube temperature is provided in the fluid heating tube connected in the vicinity of the end of the spiral shape, and the tube temperature in the vicinity of the fluid outlet is detected by the temperature sensor (S). Thus, the voltage applied to the conductive heating layer (3) by the electrodes (4, 4) is controlled.

Also in the fluid heating tube of the present invention, the conductive heat generating layer generates heat and heats the fluid almost as in the first aspect of the invention.
(Invention of Claim 3)
The present invention relates to the invention according to claim 1 or 2, wherein the fluid heating tube is set so that at least the C-shaped section of the outermost surface has a volume resistivity of 10 −6 to 105 Ω · cm. In addition, the conductive heat generating layer (3) having transparency can be visually confirmed at the end of the tube .
(Invention of Claim 4)
This invention relates to the invention described in any one of the claims 1 to 3, the innermost layer of the fluid heating tubes are assumed to have an insulating layer in contact with the fluid (2).
(Invention of Claim 5 )
This invention relates to the invention described in any one of the claims 1 to 4, wherein the fluid heating tube is assumed to have been formed with a thermosetting resin.
(Invention of Claim 6)
A heating method for a fluid heating tube according to the present invention is a method for raising the temperature of a fluid in the tube using the fluid heating tube heating device according to any one of claims 1 to 5 , wherein A tube in which the heat generating layer is formed in the longitudinal direction is sandwiched between a pair of electrodes, and a voltage is applied in the tube diameter direction, whereby the conductive heat generating layer is heated to raise the temperature of the fluid in the tube.

  According to this method, since the tube in which the conductive heat generating layer is formed in the longitudinal direction is sandwiched between the pair of electrodes and a voltage is applied in the tube diameter direction, the conductive heat generating layer generates heat simultaneously in the entire range of voltage application. As a result, the fluid is heated more uniformly. Further, since the distance between the pair of electrodes is about the diameter of the tube, the conductive heat generation layer quickly generates heat. That is, according to this method, the fluid flowing in the tube can be heated quickly and uniformly.

  The present invention is configured as described above and has the following effects.

  When this fluid heating tube and fluid heating tube heating method are used, the fluid can be heated more efficiently than when the tube is brought into contact with an external heater / heat source and transferred to the fluid. It is possible to provide a fluid heating tube and a fluid heating tube heating device that can be heated uniformly over the entire length.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
As shown in FIG. 1, the trace amount analysis fluid heating tube of this embodiment is a small-diameter tube that raises the temperature of a fluid (such as a collected sample for analysis). The diameter of the inner diameter is preferably 8 mm or less, and more preferably 3 mm or less from the viewpoint of temperature rise efficiency. For example, the outer diameter (mm) −the inner diameter (mm) can be 3-2φ or 3-1φ.

  This self-heating tube is formed by extrusion molding with a thermoplastic resin (ETFE resin), and a small-diameter process tube can be integrally formed continuously and cut into an arbitrary length for use. Moreover, it can also form with PFA resin other than the said thermoplastic resin.

As shown in FIG. 1, this microfluidic heating tube has an insulating layer 2 (base ETFE resin) in contact with the fluid in its innermost layer, and a conductive heat generating layer 3 laminated in the longitudinal direction on the outer layer side. The The conductive heat generating layer 3 can be provided in the outer layer (see FIG. 1). In the conductive heat generating layer 3, a resin or a substance (for example, conductive carbon, metal powder, carbon fiber, metal fiber, carbon nanotube) having a property of generating heat by conducting with respect to the base ETFE resin is mixed and contained. ing.
In addition, depending on the mixed substance, a conductive heat generating layer having transparency can be formed. In this case, the internal fluid can be easily confirmed visually at the end of the tube. The volume resistivity of the conductive heat generating layer 3 is set to be 10 ⁻⁶ to 10 ⁵ Ω · cm, and there is an advantage that the temperature can be set freely.

Then, as shown in FIGS. 2A and 2B, the conductive heating layer 3 is caused to generate heat by sandwiching a microfluidic heating tube between a pair of electrodes 4 and 4 and applying voltages 4 and 4 in the tube diameter direction. Thus, the temperature of the fluid can be raised. Specifically, as shown in FIG. 2 (the tube size is set to 2.2-1φ), the temperature of the tube near the outlet of the fluid is detected by a temperature sensor S, and the electrodes 4 to the conductive heating layer 3 are detected. The applied voltage is controlled by 4. Here, in this embodiment, the tube sandwiched between the pair of electrodes 4 and 4 has a spiral shape as shown in FIG . Accordingly, the entire range of the voltage application becomes a considerably long range and the conductive heating layer 3 generates heat at the same time, and since the distance between the electrodes is short, the fluid is not only heated more uniformly but also quickly. The temperature will rise.

  For example, in order to bring the collected sample for analysis (fluid) close to the same condition as in the living body, the temperature is raised from room temperature (atmosphere temperature 15 to 25 ° C.) to about 35 to 37 ° C. which is close to body temperature. Can be used as a small-diameter process tube introduced into an analytical instrument (not shown). In some cases, the temperature is raised to a higher temperature such as 80 ° C.

  Further, the microfluidic heating tube according to FIG. 1 was manufactured by extrusion molding using a two-type two-layer multilayer tube mold.

  Next, the usage state of the microfluidic heating tube of this embodiment will be described.

  In this microfluidic heating tube, a voltage is applied to the conductive heat generating layer 3 on the outer layer side of the insulating layer 2 in contact with the fluid to generate heat, and the fluid is heated via the innermost insulating layer 2. There is an advantage that it can be heated considerably more efficiently than when a tube is brought into contact with a heater / heat source and heat is transferred to a fluid. Here, it is more excellent in heat transfer efficiency if the inner insulating layer 2 is thinner than the conductive heat generating layer 3 if possible.

Further, the tube temperature in the vicinity of the fluid outlet is detected to control the voltage applied to the conductive heat generating layer 3, so that the tube in the vicinity of the fluid outlet does not need to be directly measured. The applied voltage can be adjusted depending on the temperature, and the temperature of the fluid has been raised near the outlet (37 ° C.) compared to the vicinity of the fluid inlet (15 to 25 ° C.), and the tube temperature at this position is detected. This has the advantage that the temperature of the actual fluid in the tube can be more accurately evaluated.
(Embodiment 2)
Differences from the above embodiment will be mainly described.

  As shown in FIG. 3, this microfluidic heating tube is a small-diameter tube that raises the temperature of the fluid. The conductive heat generating layer 3 is formed in a spiral shape, and a voltage is applied to the conductive heat generating layer 3 to generate heat. To heat the fluid. In this embodiment, the tube itself is made of a single material made of a conductive heat generating material.

  This microfluidic heating tube was manufactured using a single-layer tube mold.

This microfluidic heating tube heats the fluid by heating the fluid by applying a voltage to the spiral heating conductive layer 3 in the tube diameter direction, so that the tube contacts the external heater / heat source. It is possible to heat more efficiently than to transfer heat to the fluid. In particular, when heating is performed for an insulating fluid, there is an advantage that it can be implemented with a simple structure. Further, since the tube itself is made of a single material made of a conductive heat generating material, there is an advantage that it can be efficiently heated and recycled because the materials are not mixed.
(Embodiment 3)
In the first embodiment, the tubular conductive heat generating layer 3 is formed. However, the present invention is not limited to this, and the conductive heat generating layer 3 may be formed in a C-shaped cross section as shown in FIG. Good. In addition, what is necessary is just to take the form which the part which the electroconductive heat generating layer 3 lacks is supplemented with the insulating layer 2. When the transparent insulating layer 2 is used, the internal fluid can be easily confirmed visually at the end of the tube.
(Other)
The embodiment according to the present invention is not limited to the first to third embodiments. In short, it is only necessary that the outer surface is a conductive heat generating layer and can be sandwiched between a pair of electrodes.

  The present invention can be applied to various fluid heating tube applications such as a process tube that heats a specimen or other fluid to about body temperature and supplies the fluid to an analytical instrument.

In Embodiment 1 of the fluid heating tube of the present invention, (A) is a sectional view in the axial direction, (B) is a sectional view in the longitudinal direction, and (C) is a perspective view of the main part. (A) is a side view explaining the use condition of the tube for fluid heating of FIG. 1, (b) is a top view explaining the use condition of the tube for fluid heating of FIG. In Embodiment 2 of the fluid heating tube of this invention, (A) is a sectional view in the axial direction, (B) is a sectional view in the longitudinal direction, and (C) is a perspective view of the main part. In Embodiment 3 of the fluid heating tube of this invention, (A) is a sectional view in the axial direction, (B) is a sectional view in the longitudinal direction, and (C) is a perspective view of the main part. The perspective view which shows the conventional exothermic tube (FIG. 1 of patent document 1)

Explanation of symbols

2 Insulating layer 3 Conductive heating layer

Claims (6)

A tube for heating a fluid , wherein a fluid heating tube having at least an outermost surface in the longitudinal direction formed of a conductive heating layer (3) is formed in a spiral shape, and a pair having a width including the spiral shape. With the electrodes (4, 4), the conductive heat generating layer (3) is heated by sandwiching the entire tube from the front and back sides and applying a voltage in the tube diameter direction, thereby raising the temperature of the fluid in the tube. A fluid heating tube heating apparatus . A temperature sensor (S) for detecting the tube temperature is provided in the fluid heating tube connected in the vicinity of the end portion of the spiral shape, and the temperature of the tube near the outlet of the fluid is detected by this temperature sensor (S). 2. The fluid heating tube heating apparatus according to claim 1, wherein the voltage applied to the conductive heat generating layer (3) by (4, 4) is controlled . The fluid heating tube is formed of a transparent conductive heat generating layer (3) set so that at least the C-shaped section of the outermost surface has a volume resistivity of 10 −6 to 105 Ω · cm. The fluid heating tube heating apparatus according to claim 1, wherein an internal fluid can be visually confirmed at an end of the tube . Heating apparatus of the fluid heating tube according to claim 1, 2 or 3 having an insulating layer in contact with the fluid in the innermost layer of the fluid heating tube (2). Heating apparatus of the fluid heating tube according to any one of the fluid heating tube according to claim 1 to 4 which is formed of a thermosetting resin. A method for heating the fluid in the tube using the fluid heating tube heating device according to any one of claims 1 to 5 , wherein the conductive heat generating layer (3) is formed in the longitudinal direction. A heating method for a fluid heating tube, wherein the tube is sandwiched between a pair of electrodes and a voltage is applied in the tube diameter direction to thereby generate heat in the conductive heating layer (3) to raise the temperature of the fluid in the tube.

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