JPH09320623A - Electrically insulated joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable electrically insulated joint that is so excellent in mechanical connecting strength that it can surely prevent a coolant from leaking out. SOLUTION: First and second inside pipes 11, 12 are sufficiently spaced apart and placed opposite to each other. In each of the first and second pipes 11, 12 a small diameter part, a taper part 20, and a large-diameter end are formed toward their end faces 11a, 12a. A third pipe 13 covering the pipes integrally from a portion of the small diameter part of the first pipe 11 to a portion of the small diameter part of the second pipe 12 is provided via a sleeve 10, the inner periphery of the third pipe 13 being shaped to suit the shape of the outer periphery of each of the first and second pipes 11, 12. A center large-diameter part, a taper part on each side, and a small-diameter end on each side are formed in the third pipe 13. The small-diameter ends on both sides of the sleeve 10 project by a predetermined size beyond the end faces 13a, 13b on both sides of the third pipes 13, these projecting parts covering the outer peripheral surfaces of the small diameter parts of the first and second pipes 11, 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrically insulating joint for electrically insulating and mechanically connecting fluid conduits, and more particularly, to a fluid coupling inside a fuel cell stack assembly. The present invention relates to an electrically insulated joint for preventing leakage and spouting due to pressure.

[0002]

2. Description of the Related Art A fuel cell stack is formed by stacking a plurality of fuel cells on top of each other and electrically connecting the stacked fuel cells in series or parallel to each other. To be done. Power generation by this fuel cell stack is performed by electrochemically reacting a fuel having a high hydrogen concentration with an oxidant (typically oxygen is used).

A large electric output can be obtained by using such a fuel cell stack. Then, in power generation using this fuel cell stack, the higher the pressure to be implemented, that is, the power generation section, reaction section, and
Also, the higher the pressure of the coolant or the like, the more the efficiency of power generation can be improved. The fuel cell stack thus pressurized is housed in a pressure resistant container.

Also, various fluids used for operating such a fuel cell stack, such as fuel, air, and all coolants, are supplied from the outside of the fuel cell stack to the inside of the fuel cell stack. There must be. Typically, a manifold is used to supply reactants and cooling fluids such as water to the components of the fuel cell stack. That is,
A reactant is supplied to the fuel cell and a cooling fluid is supplied to the cold plate assembly.

By the way, the above manifold is
It is attached to the side of the power generation section by a caulking joint, clamp connection, or other method. In this attachment, the manifold is electrically insulated from the power generation section of the fuel cell stack, if necessary.
When the manifold is a coolant manifold, a supply coolant manifold is provided on one side of the fuel cell stack, and a discharge coolant manifold is provided on the opposite side of the fuel cell stack. It is provided.

On the other hand, the cooling plate assembly of the fuel cell stack is distributed over the entire area of the fuel cell, and
One cooling plate assembly cools a plurality of fuel battery cell assemblies. The coolant manifold is then connected to each cold plate assembly by an electrically insulating joint. This is to prevent the charge in the cold plate assembly from transferring to the coolant manifold. These coolant manifolds include
A plurality of tubular nipples are mounted, one for each cold plate assembly. In addition, a tubular nipple corresponding to the nipple of the coolant manifold is attached to each cooling plate assembly.

A sleeve or a hose connects between each of the cooling plate assemblies and the corresponding nipple of the coolant manifold. This sleeve or hose is PT
It is made of insulating material such as FE. Such a connecting structure is described, for example, in U.S. patent application Ser. No. 932,849 (filed Nov. 20, 1986, Applicant Taylor et al.). In this case, the passage connecting the manifold and the cooling plate has a relatively small diameter, and the diameter thereof is about 8 to
It is about 15 mm. Then, in such a small-diameter passage, it is possible to easily secure sufficient strength to prevent leakage and ejection of the pressurized coolant. In such small diameter passages, the pressure applied to the insulating material sleeve or hose is typically about 10 to 10.
It is about 25 kg / cm ² . The temperature of the insulating material in this case reaches about 170 ° C to 210 ° C. The voltage that can be insulated between the sleeve or hose and the cooling plate and the manifold is about 500 V or less.

On the other hand, when a large amount of power is generated using a large number of fuel cell stacks, a coolant is introduced from the outside of the fuel cell stacks in order to cool all the fuel cell stacks used, This coolant will be circulated through all fuel cell stacks used. In the case of cooling such a large number of fuel cell stacks, a coolant such as cooling water is supplied to the pressure resistance of each fuel cell stack through a coolant supply pipe attached outside the pressure vessel of each fuel cell stack. It is sent into the container and flowed in the pressure resistant container of each fuel cell stack. The coolant thus flowing in the pressure resistant container of each fuel cell stack is discharged to the outside through the coolant discharge pipe attached to the outside of the pressure resistant container, like the coolant supply pipe.

As described above, in the power generation section using a large number of fuel cell stacks, the coolant manifold for supply and the coolant manifold for discharge are arranged inside each pressure vessel of each fuel cell stack. Has been done. The connection between the external coolant supply pipe or the coolant discharge pipe and the coolant manifold in the pressure resistant container is made by a conduit penetrating the pressure resistant container and a manifold side conduit.

FIGS. 8 and 9 are views showing a penetrating coolant pipe 1 penetrating such a pressure vessel, a U-shaped coolant pipe 2 on the manifold side, and a coolant manifold 3, and 4 in the drawings. , The nipple of the coolant manifold 3. Further, a hose 5 (FIG. 8) or an electrically insulating joint 6 is provided between the penetrating coolant pipe 1 and the U-shaped coolant pipe 2.
(Fig. 9) electrically isolated and mechanically coupled.

That is, as shown in FIG. 8, when the penetrating coolant pipe 1 and the U-shaped coolant pipe 2 have substantially the same diameter, the connection between them is typically performed by a hose 5. In this case, both ends of the hose 5 are fixed to the respective ends of the penetrating coolant pipe 1 and the U-shaped coolant pipe 2 by clamps or the like.

Further, as shown in FIG. 9, when the outer diameter of the through coolant pipe 1 is smaller than the inner diameter of the U-shaped conduit 2, the connection between the coolant pipes 1 and 2 is typically made. It is performed by an electrically insulating joint 6. This electrical insulation type joint 6
The first pipe 11 and the second pipe 12 are arranged inside and outside, and the electrically insulating sleeve 10 is sandwiched between the inside and outside first and second pipes 11 and 12 to be coupled in a nested manner. Is formed by. Note that FIG.
In the above, as an example, the first pipe 11 is formed as the through-type coolant pipe 1, and the second pipe 12 is U.
Although the case where it is formed as a part of the V-shaped coolant pipe 2 is shown, one or both of the first pipe 11 and the first pipe 12 is provided as a separate member from these coolant pipes 1 and 2. There is also.

On the supply side, as shown by the arrow A in FIGS. 8 and 9, the coolant from the external supply coolant pipe is supplied into the pressure resistant container by the penetrating coolant pipe 1, This penetrating coolant pipe 1 to hose 5
Or electrical insulation type joint 6 and U-shaped coolant pipe 2
Is introduced into the coolant manifold 3 and is supplied from the coolant manifold 3 to each cooling plate assembly of the fuel cell stack via the nipple 4. On the discharge side, contrary to the supply side, the coolant from each cooling plate assembly of the fuel cell stack is discharged to the coolant manifold 3 via the nipple 4, and from this coolant manifold 3, U
It is guided to the penetrating coolant pipe 1 via the V-shaped coolant pipe 2 and the hose or the joint 6, and is discharged to the external discharge coolant pipe by this penetrating coolant pipe 1.

8 and 9, the diameters of the through-type coolant pipe 1 and the U-shaped coolant pipe 2 that connect the coolant manifold 3 and the external coolant pipe are specifically about It is about 40 to 80 mm. Also,
As shown in FIG. 8, the hose 5 used for connecting the pipes 1 and 2 has, for example, a length of about 600 mm and an inner diameter of about 50 mm.

Further, the electrically insulating joint 6 shown in FIG. 9 is formed, for example, as shown in FIGS. That is, as shown in FIG. 10, first, a first pipe 11, a sleeve 10 having an inner diameter substantially equal to the outer diameter of the first pipe 11, and a large diameter having an inner diameter larger than the outer diameter of the sleeve 10. The second pipe 12 is prepared. Then, as shown in FIG. 11, from the end face 11a side of the first pipe 11, a part of the sleeve 10 on one end face 10a side is covered on the outer periphery of the first pipe 11 so that the first pipe 11 and the sleeve 10 are separated from each other. Make sure that they overlap by a specified size. Then, the first pipe 11 and the sleeve 10
The tapered portion 20 is formed in the central portion of the overlapping portion with and the diameter of the portion extending from this portion to the end surface 11a of the first pipe 11 is enlarged. That is, the sleeve 10 and the first pipe 11 are enlarged so that the outer diameter of the central portion of the sleeve 10 on the first pipe 11 side is substantially equal to the inner diameter of the second pipe 13.

Thereafter, as shown in FIG. 12, the sleeve 1
0 from the other end surface 10b side, the end surface 1 of the second pipe 12
The portion on the 2a side is covered on the outer circumference of the sleeve 10 so that the end surface 12a of the second pipe 12 extends to the end surface 10 of the sleeve 10.
The part on the a side should be projected by a predetermined size. Then, a part of the second pipe 12 on the end face 12a side is drawn according to the shape of the overlapping portion of the first pipe 11 and the sleeve 10. That is, the second pipe 12
The inner diameter on the side of the end surface 12a is substantially equal to the outer diameter of the small diameter portion of the sleeve 10, and the portion of the second pipe 12 overlapping the tapered portion 20 of the sleeve 10 and the first pipe 11 is aligned with the tapered portion 20. The second pipe 12 is drawn so as to form the portion 20. As a result, a three-layer tapered portion 20 including the first pipe 11, the sleeve 10, and the second pipe 12 is formed.

[0017]

By the way, as described above, the diameters of the through-type coolant pipe 1 and the U-shaped coolant pipe 2 which connect the coolant manifold 3 to the external coolant supply pipe or the coolant discharge pipe. Is about 40 to 80 mm larger than the nipple 4 having a diameter of about 8 to 15 mm. In this case, since the water supply device installed outside the pressure vessel of the fuel cell stack acts on the fuel cells of all the fuel cell stacks in the power generation section of the power generation facility, the penetrating coolant pipe 1 and the U-shaped coolant A connection structure is required between the pipe 2 and the pipe 2, which can insulate a high voltage of the power generation unit having a structure in which fuel cell stacks are connected in series, for example, a high voltage up to about 3000V. Further, in such a connection structure between the coolant pipes 1 and 2, if the coolant leaks out, there is a possibility that an electric leakage or a short-circuit accident may occur due to the leakage, but such an inconvenience occurs. It is also required to prevent the occurrence of situations.

However, the conventional hose 5 and electric insulation type joint 6 as shown in FIGS. 8 and 9 do not sufficiently satisfy the requirements for the connection structure between the coolant pipes 1 and 2. However, it has the following problems.

First, a conventional hose 5 as shown in FIG.
Is fixed to the ends of the coolant pipes 1 and 2 by clamps or the like at both ends thereof, but since the strength of the hose 5 itself is limited, it is usually a non-conductive material woven in a mesh shape. Must be reinforced by. This complicates the connection structure between the coolant pipes and makes manufacturing difficult.

Further, as described above, when the pipes 1 and 2 of about 40 to 80 mm are connected by the hose 5 in order to insulate the high voltage of 3000 V, even if the hose 5 is a mesh-shaped non-conductive material. Even if reinforced with material,
The synergistic effect of high temperature and high pressure around the fuel cell array can damage the hose 5. In a structure using a plurality of fuel cell stacks, it is extremely inconvenient for even one such connecting hose 5 to be damaged. The flow rate of the connecting hose of the stack must be increased. This also complicates the connection structure between the coolant pipes and makes manufacturing difficult.

On the other hand, the conventional electrically-insulated joint 6 as shown in FIG. 9 has the first and second inner and outer arrangements as described above.
The sleeve 10 having electrical insulation is sandwiched between the pipes 11 and 12, and has a structure in which the sleeve 10 is coupled in a nested manner. However, in the electrically-insulated joint 6 having such a structure,
In particular, as shown in FIG. 12, the portion between the outer second pipe 12 and the sleeve 10 is a combination of the high temperature around the fuel cell array and the high pressure of the coolant regardless of the flow direction of the coolant. Since the effect is easily received, there is a possibility that the coolant leaks and spouts from this portion as shown by the arrow B in FIG.
Furthermore, if excessive temperature and pressure are applied to this portion, relative movement may occur in the direction of removal. When relative movement occurs between the pipe and the sleeve in this way, not only there is a possibility that the coolant leaks out from this portion, but the pipe must be reassembled.

The present invention has been proposed in order to solve the above problems of the prior art, and its purpose is to:
An electrically-insulated joint for electrically insulating and mechanically connecting coolant pipes inside a pressure vessel of a power generation section that uses multiple fuel cell stacks, with excellent mechanical connection strength It is possible to reliably prevent the leakage of
It is an object of the present invention to provide a highly practical electrically insulated joint which is highly reliable, has a simple structure, and is easy to manufacture. Another object of the present invention is to provide an electrically insulated joint having excellent heat resistance, withstand voltage and pressure resistance.

[0023]

According to a first aspect of the present invention, a tubular first pipe line and a tubular second pipe line are electrically connected via a tubular sleeve made of an electrically insulating material. An electrically insulating joint that is insulated and mechanically connected is characterized by having the following configuration.

First, the first and second conduits are arranged such that their respective one end faces face each other with a distance sufficient for electrical insulation. Then, a small diameter portion, a tapered portion, and a large diameter end portion are continuously formed in each of the first and second pipelines from the side opposite to the facing end surface toward the facing end surface. The large diameter end of the conduit and the large diameter end of the second conduit have substantially equal outer diameters.

Further, there is provided a cylindrical third pipe passage which collectively covers the outer peripheral surface of the portion from the middle of the small diameter portion of the first pipe passage to the middle of the small diameter portion of the second pipe passage. The third conduit has the inner peripheral shape of the third conduit adapted to the outer peripheral shapes of the first and second conduits, and the large diameter ends of the first and second conduits are provided. Large-diameter portion that overlaps the portion, tapered portions on both sides that overlap the tapered portions of the first and second conduits, and small-diameter end portions on both sides that overlap the small-diameter portions of the first and second conduits Are continuously formed.

On the other hand, the sleeve has the first and second conduits,
It is arranged so as to be sandwiched between the third conduit and the third conduit.
In this sleeve, the shape of the sleeve is adapted to the outer peripheral shape of the first and second pipelines and the inner peripheral shape of the third pipeline, and the large diameter of each of the first and second pipelines is adjusted. Of the central large-diameter portion sandwiched between the radial end portion and the large-diameter portion of the third conduit, the tapered portions of the first and second conduits, and the tapered portions of the third conduit. Tapered portions on both sides sandwiched between them, and small diameter end portions on both sides sandwiched between the small diameter portions of the first and second pipelines and the small diameter end portions of the third pipeline are continuously formed. To be done. Then, each of the small-diameter end portions on both sides of the sleeve is
It is configured to project beyond the end surface of each of the corresponding small diameter end portions of the third pipeline, and the projecting portion covers the outer peripheral surface of each of the small diameter portions of the first and second pipelines.

That is, in the electrically insulated joint according to the invention described in claim 1, each of the two inner pipes (first and second pipe lines) is provided with one taper portion, and the inner pipes are paired as a whole. And a pair of taper portions are provided on the outer one pipe (third pipe passage), and the three pipes (first to third pipe passages) are connected in a nested manner. The joint as a whole has a pair of tapered portions. Then, the sleeve made of electrically insulating material is attached to the inner 2
Sandwiched between one pipe (first and second conduits) and one outer pipe (third conduit), the ends on both sides of this sleeve cross over the end faces on both sides of the outer pipe. It is configured to project.

With this structure, the ends of the two inner pipes can be accommodated in the outer pipe, so that the ends of the inner pipe can be protected and their bending can be prevented. Further, since both ends of the outer pipe can be supported by the both ends of the sleeve, both ends of the outer pipe can be protected and their bending can be prevented.

On the other hand, in the electric insulation type joint of the present invention in which three pipes are connected in a nesting manner so as to have a pair of taper portions, the sleeve that covers the two inner pipes at once Is provided so as to project from both ends of the outer pipe, so that the leakage between the outer pipe and the sleeve, which is present in the conventional electrically insulated joint shown in FIG. 12, is present. There is no route. Further, the pressure of the coolant flowing inside the electric insulation type joint acts so as to press the pair of tapered portions outward, but the pressing force forcibly connects the inner and outer pipes. Since the component force in the axial direction acts, the mechanical bond strength can be improved. As described above, according to the present invention, since there is no coolant leakage path and the mechanical coupling strength can be improved, it is possible to easily and surely prevent the coolant leakage and spout, and to cause the coolant pressure. It is possible to prevent damage.

According to a second aspect of the invention, the first tubular pipe and the second tubular pipe are electrically insulated from each other through a tubular sleeve made of an electrically insulating material and mechanically. The electrically insulating joint to be connected is characterized by having the following configuration.

First, the first and second conduits are arranged such that the portions including the end faces opposite to each other overlap inside and outside. A large diameter portion, a constricted portion, and a large diameter end portion are continuously formed in the first conduit from the side opposite to the end surface toward the end surface, and the constricted portion has a pair of tapered portions. And a small diameter portion between them. In addition, the second conduit has a large diameter portion overlapping the large diameter end portion of the first conduit so that the inner peripheral shape of the second conduit conforms to the outer peripheral shape of the first conduit. A constricted portion that overlaps the constricted portion of one conduit and a large-diameter end portion that overlaps the large-diameter portion of the first conduit are continuously formed.

On the other hand, the sleeve is arranged so as to be sandwiched between the first and second conduits. The sleeve is sandwiched between the constricted portions of the first and second conduits so that the shape of the sleeve matches the outer peripheral shape of the first conduit and the inner peripheral shape of the second conduit. The central constriction,
Large-diameter end portions on both sides sandwiched between the large-diameter portions and the large-diameter end portions of the first and second conduits are continuously formed. Then, of the large-diameter end portions on both sides of the sleeve,
The large-diameter end portion sandwiched between the large-diameter portion of the first conduit and the large-diameter end portion of the second conduit projects beyond the end surface of the second conduit, and the protruding portion is the first It is configured to cover the outer peripheral surface of the large diameter portion of the conduit.

That is, in the electrically insulated joint according to the second aspect of the invention, one constricted portion is provided in each of the two inner and outer pipes (first and second pipe lines), and the constricted portions are superposed. And are joined in a telescopic manner, and the joint as a whole has a pair of tapered portions. Then, the sleeve made of an electrically insulating material is attached to the inner pipe (first conduit).
It is sandwiched between the outer pipe and the outer pipe (second pipe line), and one end of the sleeve is configured to project beyond the end surface of the outer pipe.

With this structure, the end of the inner pipe can be housed in the outer pipe, so that the end of the inner pipe can be protected and its bending can be prevented. Further, since one end of the sleeve can support the end of the outer pipe, the outer end can be protected and its bending can be prevented.

On the other hand, the electrically insulating joint of the present invention having such a constricted portion has a larger number of taper portions than the conventional electrically insulating joint shown in FIG. Have a section. Therefore, when the pressure of the coolant flowing inside the electric insulation type joint pushes the pair of tapered portions outward, the pressing force causes
A component force in the axial direction acts to forcibly connect the inner and outer pipes, and the mechanical bond strength can be improved. Especially,
In the present invention, since each of the inner and outer pipes is joined by the pair of tapered portions, the mechanical joining strength can be sufficiently improved.

As described above, in the present invention, the mechanical bond strength can be sufficiently improved, so that the airtightness of the connection part can be sufficiently improved, and the leakage and spouting of the coolant can be easily and surely prevented. Damage due to the pressure of the coolant can be sufficiently prevented.

According to a third aspect of the present invention, the first tubular pipe and the second tubular pipe are electrically insulated from each other through a tubular sleeve made of an electrically insulating material and mechanically insulated. The electrically insulating joint to be connected is characterized by having the following configuration.

First, the first and second conduits are arranged so that their respective one end faces face each other with a distance sufficient for electrical insulation. Then, in each of the first and second pipelines, a large diameter portion, a constricted portion, and a large diameter end portion are continuously formed from the side opposite to the end surface toward the facing end surface, respectively. The constricted portion is formed of a pair of tapered portions and a small diameter portion therebetween. Here, the large-diameter end portion of the first conduit and the large-diameter end portion of the second conduit have substantially the same outer diameter.

Further, a cylindrical third pipe line is provided which collectively covers the outer peripheral surface of a portion from the middle of the large diameter base part of the first pipe line to the middle of the large diameter base part of the second pipe line. . This third
In the conduit, the inner peripheral shape of the third conduit is adapted to the outer peripheral shapes of the first and second conduits so as to overlap the large-diameter end portions of the first and second conduits. The central large-diameter portion, the constricted portions on both sides overlapping the constricted portions of the first and second conduits, and the small-diameter end portions on both sides overlapping the small-diameter portions of the first and second conduits are continuous. Formed.

On the other hand, the sleeve has the first and second conduits,
It is arranged so as to be sandwiched between the third conduit and the third conduit.
In this sleeve, the shape of the sleeve is adapted to the outer peripheral shape of the first and second conduits and the inner peripheral shape of the third conduit so that the large diameter of each of the first and second conduits is increased. A central large-diameter portion sandwiched between an end portion and the large-diameter portion of the third conduit, between each of the constricted portions of the first and second conduits and each of the constricted portions of the third conduit. Constriction on both sides, and first and second
The small-diameter end portions on both sides sandwiched between the small-diameter portions of the conduit and the small-diameter end portions of the third conduit are continuously formed. Each of the large-diameter end portions on both sides of the sleeve protrudes beyond the end surface of the corresponding large-diameter end portion of the third conduit, and the protruding portion forms each of the first and second conduits. It is configured to cover the outer peripheral surface of the large diameter portion.

That is, in the electrically insulated joint according to the third aspect of the invention, each of the two inner pipes (first and second pipe lines) is provided with one constricted portion, and the inner pipes are paired as a whole. In addition to forming a constricted part, a pair of constricted parts is provided on one outer pipe (third pipe), and these three pipes (first to third pipes) are nested and joined. The joint as a whole has two pairs of taper portions. Then, a sleeve made of an electrically insulating material is sandwiched between two inner pipes (first and second pipelines) and one outer pipe (third pipeline) and The ends are configured to project beyond the end faces on both sides of the outer pipe.

With this structure, the ends of the two inner pipes can be accommodated in the outer pipe, so that the ends of the inner pipe can be protected and their bending can be prevented. Further, since both ends of the outer pipe can be supported by the both ends of the sleeve, both ends of the outer pipe can be protected and their bending can be prevented.

On the other hand, in the electric insulation type joint of the present invention in which the three pipes are connected in a nested manner so as to have the pair of constricted portions, the sleeve for covering the two inner pipes at once is provided. Is provided so as to project from both ends of the outer pipe, so that the leakage between the outer pipe and the sleeve, which is present in the conventional electrically insulated joint shown in FIG. 12, is present. There is no route. Further, in the electrically insulated joint of the present invention having a pair of constricted portions as described above, the taper portion is increased as compared with the conventional electrically insulated joint shown in FIG. 12, and the joint portion between the inner pipe and the outer pipe is formed. Has two pairs of taper portions. Therefore, when the pressure of the coolant flowing inside the electric insulation type joint pushes the two pairs of taper portions outward, the pushing force causes an axial direction such that the pipes inside and outside are forcibly coupled. A component force acts and the mechanical bond strength can be improved. Particularly, in the present invention, the coupling of the entire joint is performed by two pairs of tapered portions, and further, the coupling of each of the inner pipe and the outer pipe is performed by the pair of tapered portions. Therefore, the mechanical bond strength can be sufficiently improved.

As described above, in the present invention, since there is no coolant leakage path and the mechanical bond strength can be sufficiently improved, the airtightness of the joint portion can be sufficiently improved and the coolant leakage can be prevented. Ejection can be easily and reliably prevented, and damage due to the pressure of the coolant can be sufficiently prevented. The invention is particularly suitable for use with large diameter coolant pipes.

The inventions described in claims 4 to 6 are
In the invention described in any one of 3 above, the sleeve is
It is characterized by having the following configuration. The invention according to claim 4 is characterized in that the sleeve is made of a material containing a polytetrafluoroethylene resin: (CF ₂ —CF ₂ ) _n . In the invention according to claim 5, the sleeve is a perfluoroethylene propylene resin: (CF ₂
It is characterized in _{-CF 2) m (CF 3 CF} -CF 2) that is composed of a material including _n. In the invention according to claim 6, the sleeve is a perfluoroalkoxy resin: (CF
Is characterized in _{2 -CF 2) m (R f} OCF-CF 2) that is composed of a material including _n. According to the inventions according to claims 4 to 6 having the above-mentioned configurations, the sleeve is made of a material excellent in heat resistance, electrical insulation, and mechanical strength. The performance, withstand voltage performance, and withstand voltage performance can be improved.

According to a seventh aspect of the invention, in the invention according to any one of the first to sixth aspects, all of the plurality of pipelines are made of a metal material having the same linear expansion coefficient. It has a feature. According to the invention as set forth in claim 7 having the above-mentioned configuration, all the pipelines are made of a metal material having the same linear expansion coefficient, so that all the pipelines with respect to ambient temperature changes. Similarly, since it expands and contracts, it is possible to improve the heat resistance performance, withstand voltage performance, and pressure resistance performance of the electrically insulating joint.

[0047]

BEST MODE FOR CARRYING OUT THE INVENTION A plurality of embodiments of an electrically insulating joint according to the present invention will be specifically described below with reference to FIGS. The same parts as those of the conventional example shown in FIGS. 8 to 12 are designated by the same reference numerals, and the description thereof will be omitted.

[1. First Embodiment] [1-1. Configuration] FIG. 1 is a cross-sectional view showing one embodiment of an electrically insulated joint to which the inventions of claims 1, 4 to 7 are applied as a first embodiment of the present invention. As shown in FIG. 1, in the present embodiment,
Sleeve 10, first pipe 11, and second pipe 12
In addition to this, the third pipe 13 is used. That is, in the present embodiment, the inner first and second pipes 11,
12 is provided with each one taper portion 20 to form a pair of taper portions 20 on the entire inner pipe, and a pair of taper portions 20 is provided on the outer third pipe 13 to connect the three pipes 11 to 13. It is formed in a nested manner and is coupled via a sleeve 10.

First, the first and second pipes 11 and 12 are
The end faces 11a, 12a are arranged so as to face each other with a distance sufficient for electrical insulation. Of these, the first pipe 11 is continuously formed with a large diameter end including the small diameter portion, the tapered portion 20, and the end surface 11a from the side opposite to the end surface 11a toward the end surface 11a. Similarly, also in the second pipe 12, from the side opposite to the end face 12a toward the end face 12a, the small diameter portion, the tapered portion 20,
And a large-diameter end portion including the end surface 12a is continuously formed. And, the large diameter ends of the first and second pipes 12 are
The outer diameters are substantially equal to each other.

Further, the third pipe 13 is the first pipe 11
Is provided so as to collectively cover the outer peripheral surface of the portion from the middle of the small diameter portion of the second pipe 12 to the middle of the small diameter portion of the second pipe 12, and the inner peripheral shape of the first and second pipes 11, 1
It is formed so as to conform to the outer peripheral shape of No. 2. That is, in the central portion of the third pipe 13, a large-diameter portion that overlaps with a portion from the large-diameter end portion of the first pipe 11 to the large-diameter end portion of the second pipe 12 is formed. Then, on both sides of the large diameter portion at the center of the third pipe 13, the first and second
The tapered portions 20 overlapping the tapered portions 20 of the pipes 11 and 12 and the small diameter end portions overlapping the small diameter portions of the first and second pipes 11 and 12 are continuously formed. In this case, the small-diameter end portions on both sides of the third pipe 13 are
Both end surfaces 13a and 13b are included.

The inner diameter of each portion of the third pipe 13 is larger than the outer diameter of the corresponding portion of the first and second pipes 11 and 12 by the thickness of the sleeve 10.
Each of the three pipes 11 to 13 is made of a metal material having the same linear expansion coefficient, for example, stainless steel.

On the other hand, the sleeve 10 includes the first and second inner parts.
Are arranged so as to be sandwiched between the outer pipes 11 and 12 and the outer third pipe 13, and the inner peripheral shape and the outer peripheral shape thereof are respectively the first and second pipes 1.
The outer peripheral shapes of 1 and 12 and the inner peripheral shape of the third pipe 13 are formed. That is, at the center of the sleeve 10, the first and second pipes 11, 1
A large-diameter portion is formed between each large-diameter end portion of 2 and the central large-diameter portion of the third pipe 13. Then, on both sides of the large-diameter portion in the center of the sleeve 10, each tapered portion sandwiched between each tapered portion 20 of the first and second pipes 11 and 12 and each tapered portion 20 of the third pipe 13. 20 and each small diameter portion of the first and second pipes 11 and 12 and the third pipe 1
The small-diameter end portions sandwiched between the small-diameter end portions 3 and 3 are continuously formed. The small-diameter end portions on both sides of the sleeve 10 include respective end surfaces 10a and 10b on both sides.

In this case, the dimension of the overlapping portion between the sleeve 10 and each of the first and second pipes 11 and 12 is a predetermined dimension: L ₁ . Further, each of the small-diameter end portions on both sides of the sleeve 10 has an end surface 1 on both sides of the third pipe 13.
It projects by a predetermined dimension: L ₂ beyond 3a, 13b, and this projecting portion covers the outer peripheral surfaces of the small diameter portions of the first and second pipes 11, 12. That is, the portions on both sides of the third pipe 13 overlap with the first or second pipes 11 and 12 via the sleeve 10, thereby forming three layers of overlapping portions. dimension of the overlapping portion of the three layers, predetermined dimensions: has a _{L 3 (L 3 = L 1} -L 2).

The inner diameter of each part of the sleeve 10 is
The outer diameters of the corresponding portions of the first and second pipes 11 and 12 are made substantially equal to each other, and the outer diameter of each portion is the same as that of the third pipe 13.
Is substantially equal to the inner diameter of the corresponding part of the. Also,
This sleeve 10 is made of insulating material such as PTFE and FE.
It is made of any one of P and PFA.

Further, FIG. 2 shows a through type coolant pipe 1 and a coolant manifold 3 penetrating a pressure vessel by using the electrical insulation type joint of the present embodiment having the above structure.
It is a block diagram which shows the state which connected with the U-shaped coolant pipe 2 of the side. Except for the electrically insulating joint 6, the structure of the other parts is exactly the same as the structure of the conventional example shown in FIG. 8 or 9. That is, the first pipe 11 is formed as the penetrating coolant pipe 1, and the second pipe 12 is
It is formed as part of the U-shaped coolant pipe 2.

[1-2. Method of Forming Joint] FIG.
FIG. 6 is a cross-sectional view showing a method for forming an electrically insulating joint as shown in FIG. Hereinafter, an example of a method for forming the electrically insulating joint according to the present embodiment will be briefly described with reference to FIG.

As described above, the electric insulation type joint of the present embodiment is one in which the three pipes 11 to 13 are nested and are coupled to each other through the sleeve 10, and have a pair of tapered portions 20. Is. When forming such an electrically insulated joint, first, the first and second pipes 1 having a small diameter are first formed.
1, 12, a sleeve 10 having an inner diameter substantially equal to the outer diameters of these pipes 11, 12, and a large-diameter third pipe 13 having an inner diameter larger than the outer diameter of the sleeve 10 are prepared.

Then, as shown in FIG. 3, the first pipe 1
From one end surface 11a side, one end surface 10 of the sleeve 10
The portion on the a side is covered on the outer circumference of the first pipe 11 so that the first pipe 11 and the sleeve 10 overlap each other by a predetermined dimension: L ₁ . Subsequently, the taper portion 20 is formed in the central portion of the overlapping portion of the dimension L ₁ of the first pipe 11 and the sleeve 10, and the diameter of the portion from this portion to the end surface 11a of the first pipe 11 is determined. Enlarge and process. That is, the sleeve 10 and the first pipe 11 are enlarged so that the outer diameter of the central portion of the sleeve 10 on the first pipe 11 side becomes substantially equal to the inner diameter of the third pipe 13.

Thereafter, as shown in FIG. 3, the sleeve 10
From the other end surface 10b side, the whole of the third pipe 13 is covered on the outer circumference of the sleeve 10, and both ends of the sleeve 10 project from the end surfaces 13a, 13b on both sides of the third pipe 13 by a predetermined dimension L _2. To do so. continue,
A part of the end surface 13a side of the third pipe 13 is drawn in accordance with the overlapping portion of the sleeve 10 and the first pipe 11. That is, the inner diameter of the end portion of the third pipe 13 on the end face 13a side is substantially equal to the outer diameter of the small diameter end portion of the sleeve 10, and the sleeve 10 in the third pipe 13 is
The portion overlapping with the tapered portion 20 of the third pipe 1 is formed so as to form the tapered portion 20 aligned with the tapered portion 20.
3 is drawn. As a result, the predetermined dimension of the first pipe 11, the sleeve 10, and the third pipe 13: L ₃
The taper portion 2 is provided at the center of the three-layer portion (L ₃ = L ₁ −L ₂ ).
0 is formed.

Further, from the end surface 10b side of the sleeve 10, the end surface 12 of the second pipe 12 is inserted into the sleeve 10.
The portion on the a side is inserted into the inner circumference of the sleeve 10 so that the second pipe 12 and the sleeve 10 overlap each other by a predetermined dimension: L ₁ . Subsequently, the taper portion 20 is formed in the central portion of the overlapping portion of the dimension L ₁ of the second pipe 12 and the sleeve 10, and the diameter of the portion from this portion to the end surface 12a of the second pipe 12 is set. Enlarge and process. That is, the sleeve 10 and the second pipe 12 are enlarged so that the outer diameter of the central portion of the sleeve 10 on the second pipe 12 side becomes substantially equal to the inner diameter of the third pipe 13.

Finally, a part of the third pipe 13 on the end face 13b side is drawn so as to match the overlapping portion of the sleeve 10 and the second pipe 12. That is, the inner diameter of the end portion of the third pipe 13 on the end face 13b side is substantially equal to the outer diameter of the small diameter end portion of the sleeve 10, and the portion of the third pipe 13 that overlaps the tapered portion 20 of the sleeve 10 is The third pipe 13 is drawn so as to form the tapered portion 20 that matches the tapered portion 20. As a result, like the first pipe 11 side, the second pipe 12, the sleeve 10,
And a predetermined dimension composed of the third pipe 13: L ₃ (L ₃ =
A tapered portion 20 is formed at the center of the three-layer portion (L ₁ -L ₂ ).

[1-3. Operation] According to the present embodiment having the above-described configuration, the ends of the inner first and second pipes 11 and 12 can be housed in the outer third pipe 13, so that the inner pipe 11, The end of 12 can be protected and its bending can be prevented. Further, since both ends of the outer third pipe 13 can be supported by the both ends of the sleeve 10, both ends of the outer third pipe 13 can be protected and their bending can be prevented.

On the other hand, in this embodiment, the three pipes are connected in a nested manner so as to have the pair of tapered portions, and in particular, the first and second pipes 11 on the inner side are connected. , 12 are collectively provided so as to project from both ends of the outer third pipe 13 by a predetermined dimension: L _2, so that the conventional electrically insulated joint shown in FIG. There is no leakage path between the outer pipe and the sleeve as was present in the. Further, the pressure of the coolant flowing inside the electric insulation type joint acts so as to press the pair of tapered portions 20 in the outward direction, and this pressing force forcibly connects the inner and outer pipes. Since an axial component force acts, the mechanical coupling strength can be improved.

[1-4. [Effect] As described above, in the present embodiment, since there is no coolant leakage path and the mechanical coupling strength can be improved, it is possible to easily and surely prevent the coolant from leaking out, and at the same time, to cool the coolant. It is possible to prevent damage due to the pressure. In particular, this embodiment is suitable for connecting pipes having the same diameter. Furthermore, in the present embodiment, the sleeve 10
Heat resistance, such as PTFE, FEP, and PFA,
In addition to being made of a material excellent in electrical insulation and mechanical strength, all of the first to third pipes 11 to 13 are
Since it is made of a metal material having the same linear expansion coefficient, it is possible to obtain high heat resistance performance, withstand voltage performance, and pressure resistance performance of the electrically insulated joint.

[2. Second Embodiment] [2-1. Structure] FIG. 4 is a sectional view showing an embodiment of an electrically insulated joint to which the inventions of claims 2, 4 to 7 are applied, as a second embodiment of the present invention. As shown in FIG. 4, in the present embodiment,
Sleeve 10, first pipe 11, and second pipe 12
This is similar to the conventional example shown in FIG. 12 in that these three members are superposed by using only one, but in this three-layer portion, not only one taper portion is provided, but also a pair of taper portions are provided. The difference is that a constricted portion 30 including a portion 20 and a small diameter portion therebetween is provided. That is, in the present embodiment, one constricted portion 30 is provided on each of the inner and outer first and second pipes 11 and 12, and the first and second pipes 11 and 12 are nested and the sleeve 10 is interposed. Combined with each other.

First, the first and second pipes 11 and 12 are
The portions including the end faces 11a and 12a which are opposite to each other are arranged so as to overlap the inside and outside. Of these, the end face 11a is attached to the first pipe 1 from the side opposite to the end face 11a.
Toward the large diameter portion, the constricted portion 30 (the pair of tapered portions 2
0 and a small diameter portion between them), and a large diameter end portion including the end surface 11a are continuously formed.

Similarly, the end face 1 of the second pipe 12 is also included.
From the side opposite to 2a toward this end surface 12a, the large diameter portion,
A constricted portion 30 (a pair of tapered portions 20 and a small diameter portion between them) and a large diameter end portion including the end surface 11a are continuously formed. In this case, the second pipe 12 passes from the middle of the large-diameter portion of the first pipe 11 through the constricted portion 30 to the end surface 11a.
It is provided so as to cover the outer peripheral surface of the portion up to the large diameter end portion on the side, and the inner peripheral shape thereof is formed so as to conform to the outer peripheral shape of the first pipe 11. That is, the constricted portion 30 of the second pipe 12 is
The constricted part 30 of the second pipe 12 overlaps the constricted part 30 of the
The large diameter portions on both sides of 0 are formed so as to overlap the large diameter portions on both sides of the first pipe 11, respectively.

The inner diameter of each portion of the second pipe 12 is larger than the outer diameter of the corresponding portion of the first pipe 11 by the thickness of the sleeve 10. The first and second pipes 11 and 12 are both made of a metal material having the same linear expansion coefficient, for example, stainless steel.

On the other hand, the sleeve 10 is arranged so as to be sandwiched between the inner first pipe 11 and the outer second pipe 12, and the inner peripheral shape and the outer peripheral shape thereof are respectively the first pipe. It is formed so as to conform to the outer peripheral shape of 11 and the inner peripheral shape of the second pipe 12. That is, in the center of the sleeve 10, there is formed a constricted portion 30 sandwiched between the constricted portions 30 of the first and second pipes 11 and 12. The first and second pipes 1 are provided on both sides of the necked portion 30 of the sleeve 10.
Large-diameter end portions sandwiched between large-diameter portions 1 and 12 and large-diameter end portions are respectively formed. The large-diameter end portions on both sides of the sleeve 10 include respective end surfaces 10a and 10b on both sides.

In this case, the sleeve 10 and the first pipe 11
The dimension of the overlapping portion with is a predetermined dimension: L ₁ . The large-diameter end portion of the sleeve 10 on the side of the one end surface 10 a projects beyond the end surface 12 a of the second pipe 12 by a predetermined dimension L _2, and the projecting portion is the outer circumference of the large-diameter portion of the first pipe 11. Covering the face. That is, the second pipe 1
A part of the end surface 12a of the second member 2 is located on the first side through the sleeve 10.
It overlaps with the pipe 11, thereby forming an overlapping portion of three layers. The dimension of the overlapping portion of these three layers is a predetermined dimension: L ₃ (L ₃ = L ₁ −L ₂ ). There is. Further, the large-diameter end portion of the sleeve 10 on the side of the other end surface 10b largely protrudes beyond the end surface 11a of the first pipe 11, and this protruding portion overlaps the inner peripheral surface of the large-diameter portion of the second pipe 12. .

The inner diameter of each part of the sleeve 10 is
The outer diameter of the corresponding portion of the first pipe 11 is made substantially equal, and the outer diameter of each portion is made substantially equal to the inner diameter of the corresponding portion of the second pipe 12. In addition, this sleeve 1
0 is an insulating material such as PTFE, FEP, and PFA
It is composed of any one of the materials.

Further, FIG. 4 shows a through type coolant pipe 1 and a coolant manifold 3 penetrating a pressure vessel using the electrically insulating joint of the present embodiment having the above-mentioned structure.
It is a block diagram which shows the state which connected with the U-shaped coolant pipe 2 of the side. Except for the electrical insulation type joint 6, the configuration of the other parts is exactly the same as the configuration of the first embodiment.

[2-2. Method of Forming Joint] Hereinafter, an example of a method of forming the electrically insulating joint of the present embodiment will be briefly described. As described above, the electric insulation type joint of the present embodiment is one in which two pipes 11 and 12 are nested and coupled via the sleeve 10, and have one constricted portion 30. When forming such an electrically insulated joint, first, the first pipe 11 having a small diameter is first formed.
A sleeve 10 having an inner diameter substantially equal to the outer diameter of the first pipe 11 and a large-diameter second pipe 12 having an inner diameter substantially equal to the outer diameter of the sleeve 10 are prepared.

Then, from the end face 11a side of the first pipe 11, the part of the sleeve 10 on one end face 10a side is covered on the outer periphery of the first pipe 11, and the first pipe 11 and the sleeve 10 have a predetermined dimension: L. Only _one overlap. Subsequently, a pair of taper portions 20 are provided at the center of the overlapping portion of the dimension L ₁ of the first pipe 11 and the sleeve 10.
And a constricted portion 30 having a small diameter portion therebetween is formed, and the diameter of this portion is reduced.

After this, the other end surface 10b of the sleeve 10 is
From the side, the end face 12a side of the second pipe 12 is covered on the outer circumference of the sleeve 10, and the end face 1 of the second pipe 12 is covered.
A portion of the sleeve 10 on the side of the end face 10a projects from 2a by a predetermined dimension: L ₂ . Subsequently, the second pipe 12 is drawn so that the portion of the second pipe 12 that overlaps the constricted portion 30 of the sleeve 10 forms the constricted portion 30 that matches the constricted portion 30. As a result, the constricted portion 30 is formed in the central portion of the three-layer portion including the first pipe 11, the sleeve 10, and the second pipe 12 and having the predetermined dimension: L ₃ (L ₃ = L ₁ −L ₂ ).

[2-3. Operation] According to the present embodiment having the above-described configuration, the end of the inner first pipe 11 can be housed in the outer second pipe 12, so that the end of the inner first pipe 11 is protected. However, the bending can be prevented. Further, since the end of the outer second pipe 12 can be supported by the end of the sleeve 10, the end of the outer second pipe 12 can be protected and its bending can be prevented.

On the other hand, in this embodiment, the number of taper portions is larger than that of the conventional electrically insulated joint shown in FIG. 12, and the pair of taper portions 20 are provided at the joints between the inner and outer pipes 11 and 12. There is. Therefore, the pressure of the coolant flowing inside the electric insulation type joint is increased by the pressing force that presses the pair of tapered portions 20 in the outward direction, so that the pipe 1 inside and outside
The component force in the axial direction acts to forcibly connect the first and the second parts, and the mechanical connection strength can be improved. In particular, in the present embodiment, each of the inner and outer pipes 11 and 12 is coupled by the pair of tapered portions 20, so that the mechanical coupling strength can be further improved.

[2-4. [Effect] As described above, in the present embodiment, since the mechanical coupling strength can be sufficiently improved, the airtightness of the coupling portion can be sufficiently improved, and the leakage and spouting of the coolant can be easily and surely prevented. Therefore, damage due to the pressure of the coolant can be sufficiently prevented. Further, similar to the first embodiment, the sleeve 10 is
In addition to being made of materials with excellent heat resistance, electrical insulation, and mechanical strength, such as PTFE, FEP, and PFA, both the first and second pipes 11 and 12 have the same linear expansion coefficient. Since it is made of a metal material having a coefficient, it is possible to obtain high heat resistance performance, withstand voltage performance, and pressure resistance performance of the electrical insulation type joint.

[3. Third Embodiment] [3-1. Configuration] FIG. 6 is a sectional view showing one embodiment of an electrically insulated joint to which the inventions of claims 3, 4 to 7 are applied, as a third embodiment of the present invention. As shown in FIG. 6, in the present embodiment,
Similar to the first embodiment, the sleeve 10 and the first to first
Although the third pipes 11 to 13 are used, in each of the three-layer portions on the first pipe 11 side and the second pipe 12 side, not only a single taper portion is provided, but also a pair of three-layer portions is used. The difference is that the constricted portions 30 including the tapered portions 20 are provided respectively.

That is, in the present embodiment, each of the first and second inner pipes 11 and 12 is provided with one constricted portion to form a pair of constricted portions on the entire inner pipe, and the outer third pipe is formed. The pipe is provided with a pair of constricted portions, and these three pipes 11 to 13 are nested and are connected through a sleeve 10. Therefore, the taper portions 20 of the three-layer portions on both sides in the first embodiment are replaced by the second taper portions.
The configuration is similar to that of the first embodiment except that the constricted portion 30 is the same as that of the first embodiment.

First, the first and second pipes 11 and 12 are
The end faces 11a, 12a are arranged so as to face each other with a distance sufficient for electrical insulation. Of these, the first pipe 11 includes a large diameter portion, a constricted portion 30 (a pair of tapered portions 20 and a small diameter portion between them), and an end surface 11a from the side opposite to the end surface 11a toward the end surface 11a. The radial end portion is continuously formed. Similarly, for the second pipe 12, the end face 1 from the side opposite to the end face 12a.
2a, the large diameter part, the constricted part 30 (the part side taper part, the small diameter part, and the end part side taper part), and the end face 12
A large-diameter end portion including a is continuously formed. And
The large diameter ends of the first and second pipes 12 have outer diameters that are substantially equal to each other.

The third pipe 13 is the first pipe 11
Is provided so as to collectively cover the outer peripheral surface of the portion from the middle of the large diameter portion of the second pipe 12 to the middle of the large diameter portion of the second pipe 12, and the inner peripheral shape thereof is the first and second pipes. 11, 1
It is formed so as to conform to the outer peripheral shape of No. 2. That is, the central portion of the third pipe 13 is formed with a central portion that overlaps with a portion from the large-diameter end portion of the first pipe 11 to the large-diameter end portion of the second pipe 12. Then, on both sides of the large diameter portion at the center of the third pipe 13, the first and second
Each constricted portion 30 that overlaps each constricted portion 30 of each of the pipes 11 and 12, and each large diameter end portion that overlaps each large diameter portion of each of the first and second pipes 11 and 12 are formed. In this case, the large-diameter end portions on both sides of the third pipe 13 include the end surfaces 13a and 13b on both sides, respectively.

The inner diameter of each portion of the third pipe 13 is larger than the outer diameter of the corresponding portion of the first and second pipes 11 and 12 by the thickness of the sleeve 10.
Each of the three pipes 11 to 13 is made of a metal material having the same linear expansion coefficient, for example, stainless steel.

On the other hand, the sleeve 10 includes the first and second inner parts.
Are arranged so as to be sandwiched between the outer pipes 11 and 12 and the outer third pipe 13, and the inner peripheral shape and the outer peripheral shape thereof are respectively the first and second pipes 1.
The outer peripheral shapes of 1 and 12 and the inner peripheral shape of the third pipe 13 are formed. That is, at the center of the sleeve 10, the first and second pipes 11, 1
A large-diameter portion is formed between each large-diameter end portion of 2 and the central large-diameter portion of the third pipe 13. On both sides of the central large-diameter portion of the sleeve 10, each constricted portion sandwiched between each constricted portion 30 of the first and second pipes 11 and 12 and each constricted portion 30 of the third pipe 13. 20 and the large diameter portions of the first and second pipes 11 and 12 and the third pipe 1
The large-diameter end portions sandwiched between the large-diameter end portions 3 and 3 are continuously formed. The large-diameter end portions on both sides of the sleeve 10 include respective end surfaces 10a and 10b on both sides.

In this case, the dimension of the overlapping portion between the sleeve 10 and each of the first and second pipes 11 and 12 is a predetermined dimension: L ₁ . Further, the large-diameter end portions on both sides of the sleeve 10 are respectively formed on the end surfaces 1 on both sides of the third pipe 13.
A predetermined size: L _{2 is} projected beyond 3a and 13b, and this projecting portion covers the outer peripheral surfaces of the large diameter portions of the first and second pipes 11 and 12. That is, the portions on both sides of the third pipe 13 overlap with the first or second pipes 11 and 12 via the sleeve 10, thereby forming three layers of overlapping portions. dimension of the overlapping portion of the three layers, predetermined dimensions: has a _{L 3 (L 3 = L 1} -L 2).

The inner diameter of each part of the sleeve 10 is
The outer diameters of the corresponding portions of the first and second pipes 11 and 12 are made substantially equal to each other, and the outer diameter of each portion is the same as that of the third pipe 13.
Is substantially equal to the inner diameter of the corresponding part of the. Also,
This sleeve 10 is made of insulating material such as PTFE and FE.
It is made of any one of P and PFA.

Further, FIG. 7 shows a through type coolant pipe 1 and a coolant manifold 3 penetrating a pressure vessel by using the electric insulation type joint of the present embodiment having the above-mentioned structure.
It is a block diagram which shows the state which connected with the U-shaped coolant pipe 2 of the side. Except for the electrical insulation type joint 6, the structure of the other parts is exactly the same as the structure of the first and second embodiments.

[3-2. Method of Forming Joint] Hereinafter, an example of a method of forming the electrically insulating joint of the present embodiment will be briefly described.

As described above, the electric insulation type joint of the present embodiment is one in which three pipes 11 to 13 are nested and are coupled through the sleeve 10, and have a pair of constricted portions 30. Is. When forming such an electrically insulated joint, first, the first and second pipes 1 having a small diameter are first formed.
1 and 12, a sleeve 10 having an inner diameter substantially equal to the outer diameters of these pipes 11 and 12, and a large-diameter third pipe 13 having an inner diameter substantially equal to the outer diameter of the sleeve 10.

Then, from the end face 11a side of the first pipe 11, a part of the sleeve 10 on the one end face 10a side is covered on the outer periphery of the first pipe 11, and the first pipe 11 and the sleeve 10 have a predetermined dimension: L. Only _one overlap. Subsequently, the diameter of the first pipe 11 and the sleeve 10 is reduced by forming a constricted portion 30 at the center of the overlapping portion of the dimension L ₁ .

Thereafter, the other end surface 10b of the sleeve 10 is
From the side, a portion on the one end face 13a side of the third pipe 13 is covered on the outer circumference of the sleeve 10, and the portion on the end face 10a side of the sleeve 10 projects from the end face 13a of the third pipe 13 by a predetermined dimension: L ₂ . To do so. Subsequently, the portion of the third pipe 13 that overlaps the constricted portion 30 of the sleeve 10 aligns with the constricted portion 30.
The third pipe 13 is drawn so as to form
As a result, the first pipe 11, the sleeve 10, and the third
Predetermined size of the pipe 13: L ₃ (L ₃ = L ₁ −
A constricted portion 30 is formed in the central portion of the three-layer portion of L ₂ ).

Further, from the side of the end surface 10b of the sleeve 10, the end surface 12 of the second pipe 12 is inserted into the sleeve 10.
The portion on the a side is inserted into the inner circumference of the sleeve 10 so that the second pipe 12 and the sleeve 10 overlap each other by a predetermined dimension: L ₁ . Then, the diameter of the second pipe 12 and the sleeve 10 is reduced by forming a constricted portion 30 at the center of the overlapping portion of the dimension L ₁ .

Finally, the third pipe 13 is drawn so that the portion of the third pipe 13 that overlaps with the constricted portion 30 on the end face 13b side of the sleeve 10 forms the constricted portion 30 that matches the constricted portion 30. . As a result, the second
A constricted portion 30 is formed at the center of a three-layer portion having a predetermined size: L ₃ (L ₃ = L ₁ −L ₂ ), which includes the pipe 12, the sleeve 10, and the third pipe 1.

[3-3. Operation] According to the present embodiment having the above-described configuration, the ends of the inner first and second pipes 11 and 12 are provided in the outer third pipe 13 as in the case of the first embodiment. Because the part can be stored, the inner pipe 1
The ends of 1 and 12 can be protected and their bending can be prevented. Further, since both ends of the outer third pipe 13 can be supported by the both ends of the sleeve 10, both ends of the outer third pipe 13 can be protected and their bending can be prevented.

On the other hand, in this embodiment, the three pipes are connected in a nested manner so as to have the pair of constricted portions, and in particular, the inner first and second pipes 11 are connected. , 12 are collectively provided so as to protrude from both ends of the outer third pipe 13 by a predetermined dimension: L ₂ , and therefore, as in the first embodiment, There is no leakage path between the outer pipe and the sleeve.

Further, in the present embodiment, the second
Similar to the embodiment described above, the number of taper portions is increased, and two pairs of taper portions 20 are provided at the connecting portion between the inner pipes 11 and 12 and the outer pipe 13. Therefore, when the pressure of the coolant flowing inside the electric insulation type joint pushes the two pairs of taper portions 20 in the outward direction, the pressing force forcibly joins the inner and outer pipes in the axial direction. The component force of is applied to improve the mechanical bond strength. In particular, in the present embodiment, the entire electrically insulating joint is coupled by two pairs of tapered portions 20, and each of the inner pipes 11 and 12 and the outer pipe 13 is connected.
Since each of the couplings with and is performed by the pair of tapered portions, the mechanical coupling strength can be sufficiently improved.

[3-4. [Effect] As described above, in the present embodiment, since the two pairs of taper portions 20 are provided and the mechanical coupling strength can be sufficiently improved, the airtightness of the coupling section can be sufficiently improved, and the cooling agent It is possible to easily and surely prevent leakage and spout, and it is possible to sufficiently prevent damage due to the pressure of the coolant. Further, the present embodiment is suitable for connecting pipes having the same diameter. Especially,
Since it has large diameter ends on both sides and has excellent airtightness and pressure resistance as described above, it is suitable for connecting a coolant pipe having a large diameter.

Further, similar to the first and second embodiments, the sleeve 10 is made of a material such as PTFE, FEP, and PFA which is excellent in heat resistance, electric insulation and mechanical strength. In addition to the above, since both the first and second pipes 11 and 12 are made of a metal material having the same linear expansion coefficient, high heat resistance performance of the electrical insulation type joint,
Withstand voltage performance and pressure resistance performance can be obtained.

[4. Other Embodiments] The present invention
The present invention is not limited to the above embodiments, and various other embodiments can be implemented. For example, specific materials for the sleeve and the pipe can be selected as appropriate. It is also possible to further develop the third embodiment and provide the constricted portions at three or more places. By increasing the number of the constricted portions in this way, the airtightness and pressure resistance can be further improved.

Further, in each of the above-mentioned embodiments, the case where the electric insulation type joint of the present invention is applied to the connection between the penetrating coolant pipe penetrating the pressure vessel and the U-shaped coolant pipe has been described. The present invention can be similarly applied to connection between various coolant pipes, and can similarly obtain excellent operational effects. Further, in each of the above embodiments, the case where both the first pipe and the second pipe are formed as all or a part of the coolant pipes to be connected has been described, but either the first pipe or the second pipe is described. It is likewise possible to form one or both as a separate member from the coolant pipe to which they are connected.

[0101]

As described above, according to the present invention, the coupling between the inner pipe and the outer pipe is performed through the pair of taper portions, so that the pressing force of the coolant for pushing the taper portions to the outer side can be obtained. Since it is possible to exert a component force in the axial direction such as forcibly connecting the inner and outer pipes, the mechanical coupling strength is superior to the conventional one, and it is possible to reliably prevent leakage of the coolant. It is possible to provide a highly practical electrically insulating joint that is highly reliable, has a simple structure, and is easy to manufacture.

Further, by appropriately selecting the material of the sleeve and the pipe, it is possible to provide an electrically insulated joint excellent in heat resistance, withstand voltage and pressure resistance.
More specifically, according to the present invention, high heat resistance performance capable of withstanding a high temperature of approximately 210 ° C., high withstand voltage performance capable of withstanding a high voltage of approximately 3000 V, and high withstand pressure of approximately 25 kg / cm ^2. It is possible to provide an electrically insulated joint having pressure resistance performance.

[Brief description of drawings]

FIG. 1 is a sectional view showing an electrically insulated joint according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a state in which a coolant pipe penetrating a pressure vessel and a coolant pipe on a coolant manifold side are connected to each other by using the electrically insulating joint of FIG.

FIG. 3 is a cross-sectional view showing a method for forming the electrically insulating joint of FIG.

FIG. 4 is a cross-sectional view showing an electrically insulated joint according to a second embodiment of the present invention.

5 is a configuration diagram showing a state in which a coolant pipe penetrating a pressure vessel and a coolant pipe on a coolant manifold side are connected to each other by using the electrically insulating joint of FIG. 4. FIG.

FIG. 6 is a cross-sectional view showing an electrically insulated joint according to a third embodiment of the present invention.

7 is a configuration diagram showing a state in which a coolant pipe penetrating a pressure vessel and a coolant pipe on a coolant manifold side are connected to each other by using the electrically insulating joint of FIG.

FIG. 8 is a configuration diagram showing a state in which a conventional hose is used to connect a coolant pipe penetrating the pressure vessel and a coolant pipe on a coolant manifold side.

FIG. 9 is a configuration diagram showing a state in which a coolant pipe penetrating a pressure vessel and a coolant pipe on a coolant manifold side are connected using a conventional electrically insulated joint.

10 is a cross-sectional view showing an initial step of the method for forming the electrically insulating joint of FIG.

FIG. 11 is a cross-sectional view showing a step in the middle of the method for forming the electrically insulating joint of FIG. 9.

FIG. 12 is a cross-sectional view showing the electrically insulated joint of FIG.

[Explanation of symbols]

 1: Through-type Coolant Pipe 2: U-Shaped Coolant Pipe 3: Coolant Manifold 4: Nipple 5: Hose 6: Electrically Insulated Joint 10: Sleeves 10a, 10b: End Face 11: First Pipe 11a: End Face 12: No. 2 pipe 12a: end surface 13: third pipe 13a, 13b: end surface 20: taper portion 30: constricted portion A: flow direction of coolant B: flow direction of leaked coolant

Claims (7)

[Claims] 1. An electrically insulated joint for electrically insulating and mechanically connecting a tubular first pipe line and a tubular second pipe line via a tubular sleeve made of an electrically insulating material. The first and second pipelines are arranged such that their respective one end surfaces face each other with a distance sufficient for electrical insulation, and each of the first and second pipelines includes: A small-diameter portion, a taper portion, and a large-diameter end portion are continuously formed from the side opposite to the end surface toward the end surface, respectively, and the large-diameter end portion of the first conduit and the second conduit are formed. The large-diameter end portions have outer diameters that are substantially equal to each other, and collectively form an outer peripheral surface of a portion from the middle of the small-diameter portion of the first conduit to the middle of the small-diameter portion of the second conduit. A cylindrical third pipe line is provided to cover the third pipe line, and the inner peripheral shape of the third pipe line is the first pipe line.
And a large-diameter portion in the center that overlaps the large-diameter end portions of the first and second pipelines so as to conform to the outer peripheral shapes of the first and second pipelines, and the first and second pipelines described above. Tapered portions on both sides that overlap the tapered portion and small-diameter end portions on both sides that overlap the small-diameter portions of the first and second conduits are continuously formed, and the sleeve includes the first and second conduits. And the third conduit, and the sleeve is arranged such that the shape of the sleeve is the outer peripheral shape of the first and second conduits and the inner circumference of the third conduit. A central large-diameter portion sandwiched between the large-diameter ends of the first and second conduits and the large-diameter portion of the third conduit so as to conform to the shape, first and second Taper portions on both sides sandwiched between the respective tapered portions of the pipeline and the respective tapered portions of the third pipeline, and the small diameter portions of the first and second pipelines and the third pipeline of the third pipeline. Small diameter end portion of each side to be sandwiched between said small diameter end portion are continuously formed, each of said opposite sides of the small-diameter end portion of said sleeve, said third
Projecting beyond the end face of each corresponding small diameter end of the conduit,
An electrically insulated joint characterized in that the projecting portion is configured to cover the outer peripheral surface of each of the small diameter portions of the first and second conduits. 2. An electrically insulated joint for electrically insulating and mechanically connecting a tubular first pipe line and a tubular second pipe line via a tubular sleeve made of an electrically insulating material. The first and second conduits are arranged such that portions including end faces opposite to each other overlap inward and outward, and in the first conduit, from a side opposite to the end face toward the end face. , A large diameter portion, a constricted portion, and a large diameter end portion are continuously formed, and the constricted portion is formed of a pair of tapered portions and a small diameter portion therebetween, and the second pipe is provided with the second pipe. The inner peripheral shape of the road is the first
A large diameter portion that overlaps the large diameter end portion of the first conduit, a constricted portion that overlaps the constricted portion of the first conduit, and the large diameter of the first conduit so as to conform to the outer peripheral shape of the conduit. A large-diameter end portion overlapping the portion is continuously formed, the sleeve is disposed so as to be sandwiched between the first and second conduits, and the sleeve has the shape of the sleeve A central constricted portion sandwiched between the constricted portions of the first and second conduits so as to conform to the outer peripheral shape of the first conduit and the inner peripheral shape of the second conduit; Two large-diameter end portions sandwiched between the large-diameter portions and the large-diameter end portions of the conduit 2 are continuously formed, and among the large-diameter end portions on the both sides of the sleeve, The large-diameter end portion sandwiched between the large-diameter portion of the first conduit and the large-diameter end portion of the second conduit is the end surface of the second conduit. Beyond protrudes, electrically insulated joint, characterized in that the projecting portion is configured to cover the outer peripheral surface of the large diameter portion of the first conduit. 3. An electrically insulating joint for electrically insulating and mechanically connecting a tubular first pipe line and a tubular second pipe line via a tubular sleeve made of an electrically insulating material. The first and second pipelines are arranged such that their respective one end surfaces face each other with a distance sufficient for electrical insulation, and each of the first and second pipelines includes: A large-diameter portion, a constricted portion, and a large-diameter end portion are continuously formed from a side opposite to the end surface toward the opposed end surface, and the constricted portion is formed of a pair of tapered portions and a small-diameter portion therebetween. The large-diameter end portion of the first conduit and the large-diameter end portion of the second conduit have outer diameters that are substantially equal to each other, and the large-diameter portion of the first conduit extends from the middle of the large-diameter portion. A cylindrical third pipe line is provided to collectively cover an outer peripheral surface of a portion of the second pipe line up to the middle of the large diameter portion, The 3 line, the inner peripheral shape of the third conduit first
And a large-diameter portion in the center that overlaps the large-diameter end portions of the first and second pipelines so as to conform to the outer peripheral shapes of the first and second pipelines, and the large-diameter portion of the first and second pipelines. Constricted parts on both sides overlapping the constricted part and small-diameter end parts on both sides overlapping the small-diameter parts of the first and second conduits are continuously formed, and the sleeve includes the first and second pipes. Is disposed so as to be sandwiched between a channel and the third pipeline, and the sleeve has a shape of the outer circumference of the first and second pipelines and an inner shape of the third pipeline. A central large-diameter portion sandwiched between the large-diameter end portions of the first and second conduits and the large-diameter portion of the third conduit so as to conform to the circumferential shape, the first and second large-diameter portions. Constricted parts on both sides sandwiched between each of the constricted parts of the second conduit and each of the constricted parts of the third conduit, and each of the small diameter parts of the first and second conduits and the third pipe Small diameter end portion of each side to be sandwiched between each of said small diameter end portion is continuously formed in each of the large diameter portion of the sides of the sleeve, the third
Projecting beyond the end face of each corresponding large diameter end of the conduit,
An electrically insulating joint, wherein the projecting portion is configured to cover the outer peripheral surface of each of the large diameter portions of the first and second conduits. 4. The sleeve according to claim 1, wherein the sleeve is made of a material containing polytetrafluoroethylene resin: (CF ₂ —CF ₂ ) _n. The electrically-insulated joint described. 5. The perfluoroethylene propylene resin: (CF ₂ —CF ₂ ) _m (CF ₃ CF—).
The electrically insulating joint according to any one of claims 1 to 3, wherein the electrically insulating joint is made of a material containing CF ₂ ) _n . 6. The sleeve comprises a perfluoroalkoxy resin: (CF ₂ —CF ₂ ) _m (R _f OCF—CF ₂ ).
The electrically insulated joint according to any one of claims 1 to 3, which is made of a material containing _n . 7. The electrically insulating type according to claim 1, wherein all of the plurality of pipelines are made of a metal material having the same linear expansion coefficient. Fittings.