JP2006283781A - Connection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To lower an insertion force during connection without impairing sealability. <P>SOLUTION: A female side tapered surface 91b corresponding to a ring outer side tapered surface 10b is formed at the positions of the ring outer side tapered surface 10b and a sealed surface 91a corresponding to a backup ring 10 on the outer peripheral side of the backup ring 10. The inside taper angle α of male side tapered surface 81b/ring inner side tapered surface 10a and the outside taper angle β of ring outer side tapered surface 10b/female side tapered surface 91b are related to be inside taper angle α>(outside taper angle β)>0°. Accordingly, since the outer peripheral side of the backup ring 10 is not so formed that its cylindrical faces are fitted to each other but so formed that the cylindrical faces are brought into contact with each other after being inserted, and also a final compression tolerance can be set with a push-in dimension after the insertion without inserting while reducing the compression tolerance from an initial stage. Thus, the insertion force during connection can be lowered. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a connecting device that prevents pressurized gas flowing inside between connecting members from leaking to the outside, and particularly relates to a connecting device that uses an O-ring and a backup ring as seal members. Is.

In recent years, development of a refrigeration cycle using CO ₂ gas (hereinafter referred to as carbon dioxide gas) as a refrigerant has been advanced in response to the flow of defluorination. In the system using carbon dioxide gas as a refrigerant, as in the conventional system, piping is used to connect each refrigeration equipment, and the connection between the piping and the refrigeration equipment, or the connection of piping joints, etc. A device is used.

  However, when carbon dioxide gas is used as the refrigerant, carbon dioxide pressurized to a pressure of about 15 MPa, for example, higher than when chlorofluorocarbon gas is used flows through the pipe. In this way, in the connection device for connecting the pipe through which the pressurized carbon dioxide gas flows, for example, an O-ring as a rubber seal member, and the O-ring rises due to the pressure difference between the gas pressure and the outside of the pipe. A backup ring is used to prevent biting and to secure the sealing performance of the O-ring.

  The O-ring is arranged so as to seal between the sealed surface of one connecting member provided at the connection part of the pipe and the sealed surface of the other connecting member, and the backup ring is provided inside and outside the connecting device. Is arranged to support the O-ring in the direction in which the O-ring moves due to the pressure difference between

  As a connection device such as a pipe joint using such an O-ring and a backup ring, the present inventors have previously filed a device disclosed in Patent Documents 1 and 2 below. FIG. 8A is a cross-sectional view showing the connection state of the connection device 7, and FIG. 8B is a partial cross-sectional view of the main part A in the mid-connection state. 9A is a cross-sectional view showing a connection state of the connection device 7, FIG. 9B is a connection halfway state, and FIG. 9C is a partial cross-sectional view of the main part A in a state where the inside is pressurized. is there.

  These pipe joints 7 are composed of a male side joint 8 and a female side joint 9 as shown in the figure, and basically have a cylindrical seal structure using an O-ring 11. The male joint 8 is formed with a cylindrical fitting convex portion 81, and the O-ring 11 is attached to the fitting convex portion 81. Further, the backup ring 10 is mounted adjacent to the opposite side of the pressure receiving surface of the O ring 11 of the fitting convex portion 81 to which the O ring 11 is mounted. 8 and 9 denotes a cap as a member for preventing the O-ring 11 and the backup ring 10 from falling off.

  The backup ring 10 is formed of a resin material that is more excellent in refrigerant permeation resistance than the O-ring 11. The female joint 9 is formed with a fitting recess 91 having a cylindrical inner periphery into which the fitting protrusion 81, the backup ring 10, the O-ring 11, and the cap 12 are fitted. By fitting the fitting convex portion 81 part, the refrigerant flow path is connected and the refrigerant is prevented from leaking to the outside (atmosphere). In these structures, the backup ring 10 is compressed by the force with which the O-ring 11 is pushed by the pressure of the refrigerant to fill the gap, thereby improving the sealing performance.

In particular, in the structure of FIG. 9, the male-side tapered surface 81 b in which the distance between the sealed surfaces 81 a and 91 a gradually decreases toward the non-pressurized side of the refrigerant, A ring inner taper surface 10a corresponding to the male taper surface 81b is provided on the inner diameter side, and when an internal pressure (refrigerant pressure) is applied, the backup ring 10 is driven into a wedge shape by the pushing force of the O-ring 11 to improve the sealing performance. It has a structure. Note that reference numerals in the drawings that are not described above correspond to reference numerals in embodiments of the present invention described later, and description thereof is omitted here.
International Publication No. 2004/061353 Pamphlet US Patent Application Publication No. 2005/0023828

  FIG. 8B is a partial cross-sectional view of the main part A in the middle of connection. In the case of the structure shown in FIG. 8, the backup ring 10 has a lower ductility than the O-ring 11, and the amount of deformation is small although it is deformed by pressure. Therefore, in order to obtain a reliable seal, the tolerance is the worst, that is, the inner diameter φF of the female-side seal surface 91a is the maximum within the tolerance, and the outer diameter φB of the backup ring 10 is reliably the same as the female-side seal surface 91a. The outer diameter of the backup ring 10 needs to be in contact.

  However, in the combination within the tolerance, since φF <φB, there is a problem that the compression cost of the backup ring 10 is large at the time of connection, a large insertion force is required, and the assemblability is poor. 9C is a partial cross-sectional view of the main part A in the middle of connection, but the dimensional relationship between the inner diameter φF of the female-side seal surface 91a and the outer diameter φB of the backup ring 10 is the same in the structure of FIG. Therefore, it becomes the same problem.

  FIG. 10 is a partial sectional view on the fitting convex portion 81 side for explaining another conventional problem. This is a problem that even if the backup ring 10 is mounted in the reverse direction, it is difficult to confirm because the outer diameter is the same. Actually, the backup ring 10 is a small part, and when the color is a natural color such as white due to the material cost, it is almost impossible to visually determine the inclination direction on the inner diameter side. However, if the O-ring 11 and the cap 12 are assembled, they will not go into the fitting recess 91, so that incorrect assembly can be determined. However, the number of reassembly steps is wasted.

  FIG. 11 is a partial cross-sectional view of the main part A in the case of separating the connection device 7 of FIG. 8 (FIG. 9), (a) is a state in which there is a residual pressure before separation, and (b) The state in the middle of separation, (c) shows the state at the moment when the inside is opened. At the time of the separation, since the internal gas remaining as the residual pressure is released at a moment when the backup ring 10 is removed from the female-side seal surface 91a, stress is applied to the worker who performs the separation work of the connecting device. It is a problem that there is a fear.

  The present invention has been made in view of these conventional problems, and an object of the present invention is to provide a connection device that can improve the assembly performance by reducing the insertion force at the time of connection without impairing the sealing performance. There is. Another object of the present invention is to provide a connection device that makes it easy to confirm the direction of the backup ring and eliminates erroneous assembly. Another object of the present invention is to provide a connection device that does not cause stress to the worker during separation work.

In order to achieve the above object, the present invention employs technical means described in claims 1 to 4. That is, the invention according to claim 1 includes a male side member (8) and a female side member (9), which are connected to each other with flow paths (8a, 9a) through which pressurized gas flows. ,
The male member (8) has a fitting projection (81) formed in a cylindrical shape,
A seal member (11) which is mounted on the outer peripheral side of the fitting convex portion (81) and seals between the sealed surfaces (81a, 91a) of the male side and female side members (8, 9);
A backup ring that supports the seal member (11) that is formed of a material that is less permeable to gas than the seal member (11) and that receives a pressure difference between the inside and outside of the male and female members (8, 9). (10)
The back-up ring (10) mounting position of the fitting convex portion (81) has a male taper surface (81b) in which the distance between the sealed surfaces (81a, 91a) gradually decreases toward the non-pressurized side of the gas. ,
The inner diameter side of the backup ring (10) has a ring inner tapered surface (10a) corresponding to the male tapered surface (81b),
The male taper surface (81b) and the ring inner taper surface (10a) compress the backup ring (10) pressed by the seal member (11) receiving the pressure difference between the surfaces to be sealed (81a, 91a). In the connection device that prevents the gas flowing through the inside in close contact with the sealed surfaces (81a, 91a) from leaking outside,
On the outer periphery side of the backup ring (10), a ring outer tapered surface (10b) inclined in the same direction as the ring inner tapered surface (10a),
At the position corresponding to the backup ring (10) of the sealed surface (91a) of the female side member (9), a female side tapered surface (91b) corresponding to the ring outer tapered surface (10b) is provided,
An inner taper angle (α) of the male taper surface (81b) and the ring inner taper surface (10a) and an outer taper angle (β) of the ring outer taper surface (10b) and the female taper surface (91b) The taper angle (α)> outer taper angle (β)> 0 degree is a feature.

  As a specific example, α = 30 degrees and β = 10 degrees. According to the first aspect of the present invention, by providing the ring outer taper surface (10b) and the corresponding female taper surface (91b), the outer peripheral side of the backup ring (10) is a conventional cylinder. Instead of fitting the surfaces together, the conical surfaces can be brought into contact with each other after insertion, and the final compression is performed with the indentation dimensions after insertion rather than inserting while compressing a predetermined compression allowance from the beginning. Since the allowance can be set, the insertion force at the time of connection can be lowered.

  3 is a partial cross-sectional view of the main part A in FIG. 2A. FIG. 3A shows a state in the middle of connection, FIG. 3B shows a connection completed state, and FIG. 3C shows a state in which the inside is pressurized. Show. As shown in the figure, since the angle difference of the inner taper angle (α)> the outer taper angle (β) is provided, the shape of the backup ring (10) and the shape of the space accommodating the backup ring (10) are not Since the taper shape gradually decreases toward the pressurization side, when the internal pressure (refrigerant pressure) is applied, the backup ring (10) is driven into a wedge shape by the pressing force of the seal member (11), thereby ensuring a structure that improves the sealing performance. (See FIG. 3C).

  As a result, in the connection device composed of a sealing member (11) such as a rubber O-ring and a resin backup ring (10), the insertion force at the time of connection is reduced without impairing the sealing performance, thereby improving the assembling performance. Can be made. FIG. 4 is a cross-sectional view of the backup ring (10) of the present invention and a plan view from both sides. As shown in the figure, when the cross-sectional shape is tapered, a difference in shape between both surfaces is increased, and the direction can be easily confirmed, thereby preventing erroneous assembly. In addition, even after the fitting convex portion (81) is mounted, the direction can be visually confirmed by the taper of the outer peripheral surface.

  5 is a partial cross-sectional view of the main part A in the case of separating the connecting device 7 of FIG. 2, (a) is a state in which there is a residual pressure before separation, (b) is a state in the middle of separation, (C) shows a state in which the inside is opened. As shown in the figure, during separation, the contact surface of the backup ring (10) gradually expands, and the internal gas remaining as residual pressure gradually escapes. The stress given can be reduced.

  According to a second aspect of the present invention, in the connecting device according to the first aspect, the first cylindrical portion (91c) on the outer side of the female taper surface (91b) provided on the female member (9). The inner diameter of the female side first diameter portion (φF1) and the inner diameter of the sealed surface (91a) on the inner side of the female side tapered surface (91b) are the female side second diameter portion (φF2), and these and the backup ring The outer diameter (φB) of (10) is characterized by the relationship of the female-side first diameter portion (φF1) ≧ the backup ring outer diameter (φB)> the female-side second diameter portion (φF2).

  As specific examples, φF1 = φ11.35, φB = φ11.3, and φF2 = φ10.75. According to the second aspect of the present invention, the backup ring (10) can be inserted without being compressed, and the assemblability can be improved by reducing the insertion force at the time of connection.

  In the invention according to claim 3, in the connection device according to claim 1 or 2, the material of the backup ring (10) is nylon resin (PA), more preferably nylon 1010. (PA1010).

  FIG. 6 is a graph comparing the ease of leakage due to the material of the backup ring (10) and the insertion force (hardness). As can be seen from the graph, nylon resin (PA6, PA11, PA66, PA612, etc.) is closest to the target values of easy leakage and insertion force (hardness), and the only nylon 1010 (PA1010) is easy to leak and insertion force (hardness). It satisfies the target value of and is the best. According to the third aspect of the invention, the refrigerant permeability can be reduced and the insertion property can be improved.

According to a fourth aspect of the present invention, in the connecting device according to any one of the first to third aspects, the gas is CO ₂ gas. According to the fourth aspect of the present invention, the present invention is used for a connection device such as a pipe joint for connecting a refrigerant flow path of a refrigeration cycle using CO ₂ gas having a high operating pressure and a high permeability coefficient as a refrigerant. Is preferred. Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with the specific means described in the embodiments described later.

(First embodiment)
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a refrigeration cycle R according to an embodiment of the present invention. The refrigeration cycle R uses carbon dioxide as a refrigerant, and is a well-known one constituted by connecting refrigeration equipment such as a refrigerant compressor 1, a refrigerant condenser 2, an expansion valve 3, a refrigerant evaporator 4 and an accumulator 5 in an annular shape. Specifically, these refrigeration equipments are connected by a refrigerant pipe 6 having a pipe joint (connecting device referred to in the present invention) 7. Incidentally, 2 a in FIG. 1 is a blower that supplies heat exchange air to the refrigerant condenser 2, and 4 a is a blower that supplies heat exchange air to the refrigerant evaporator 4.

  (A) of FIG. 2 is sectional drawing which shows the connection state of the piping joint 7 in 1st Embodiment of this invention, (b) is a fragmentary figure of the principal part A in (a), and shows the state before a connection. FIG. 2C is an enlarged cross-sectional view of the backup ring 10. The pipe joint 7 is composed of a male side joint (male side member referred to in the present invention) 8 and a female side joint (female side member referred to in the present invention) 9, and both the joints 8 and 9 have a circular refrigerant pipe 6 and a connection block. And brazed.

  Here, the refrigerant pipe 6 is usually made of a metal material such as aluminum, copper, brass, slenless or iron, and in this embodiment, aluminum A3004 clad with a skin material A4004 as a brazing material is used on the outer peripheral side. . Also, the connection block is made of the same material as that of the refrigerant pipe 6, and in this embodiment, aluminum A7000 series is used.

  The male joint 8 includes a fitting convex part 81 formed on one end side (right side in FIG. 2), a pipe insertion hole 82 formed on the other end side (left side in FIG. 2), and a fitting convex part 81 and pipe insertion. A communication hole (channel referred to in the present invention) 8 a communicating with the hole 82 and a bolt hole 83 are provided. The fitting convex portion 81 is formed in a cylindrical shape, and an O-ring 11 as a seal member, a backup ring 10 as a pressure receiving member, and a cap 12 as a drop-off preventing member are mounted on the outer periphery thereof. (See FIG. 2 (b)).

  It should be noted that the distance between the sealed surfaces 81a and 91a of the male / female joints 8 and 9 is at the non-pressurized side (external side) of carbon dioxide at the position where the backup ring 10 of the fitting convex part 81 is mounted. The male side taper surface 81b which decreases gradually toward is formed. The O-ring 11 has a donut-shaped ring shape, and has a substantially circular cross section. The O-ring 11 is made of an elastic material such as a rubber material, and IIR rubber is used in this embodiment. The space between the previous sealed surfaces 81a and 91a is sealed.

  Further, the backup ring 10 is an endless type that is continuous in the circumferential direction, and has a material having a lower refrigerant permeability than the O-ring 11, specifically, a lower refrigerant permeability and a lower hardness. Nylon 1010 is used because the insertion force is small (see FIG. 6). Thereby, not only the O-ring 11 but also the backup ring 10 enhances the refrigerant sealing performance.

  Further, on the inner diameter side of the backup ring 10, a ring inner tapered surface 10a corresponding to the previous male tapered surface 81b is provided. The backup ring 10 pressed by the O-ring 11 receiving the pressure difference between the inside and outside of the male / female joints 8 and 9 is sealed by the male tapered surface 81b and the ring inner tapered surface 10a. Compressed between the surfaces 81a and 91a and brought into close contact with the sealed surfaces 81a and 91a to prevent the carbon dioxide gas flowing through the inside from leaking to the outside.

  Further, as a feature of the present embodiment, a ring outer tapered surface 10b that is inclined in the same direction as the ring inner tapered surface 10a is provided on the outer peripheral side of the backup ring 10. The inner taper angle α of the ring inner taper surface 10a and the outer taper angle β of the ring outer taper surface 10b are 30 degrees and 20 degrees, respectively, as a specific example, and the inner taper angle α> the outer taper angle β> 0. The degree is related.

  The refrigerant pipe 6 is inserted into the pipe insertion hole 82 and joined by brazing. The bolt hole 83 is provided through the end of the male joint 8 and the bolt 13 is inserted when connected. The female joint 9 includes a fitting recess 91 formed on one end side (left side in FIG. 2), a pipe insertion hole 92 formed on the other end side (right side in FIG. 2), and a fitting recess 91. It has a communication hole (channel referred to in the present invention) 9 a communicating with the pipe insertion hole 92 and a screw hole 93. The fitting concave portion 91 forms an inner cylindrical hollow portion.

  Again, as a feature of the present embodiment, a female taper surface 91b corresponding to the ring outer taper surface 10b is provided at a position corresponding to the backup ring 10 of the sealed surface 91a of the female joint 9. The inner taper angle α of the male taper surface 81b and the outer taper angle β of the female taper surface 91b are set to 30 degrees and 20 degrees, respectively, and the inner taper angle α> the outer taper angle β. The relationship is> 0 degrees.

  Further, as the diameter dimension in the above-described shape, the inner diameter of the first cylindrical portion 91c on the outer side of the female side tapered surface 91b provided in the female side joint 9 is defined as the female first first diameter portion φF1 and the female side tapered surface 91b. Assuming that the inner diameter of the sealed surface 91a on the inner side is the female-side second diameter portion φF2, as specific examples, φF1 = φ11.35 and φF2 = φ10.75 are provided. As a specific example, the diameter φB is φB = φ11.3. Thus, the relationship is female side first diameter portion φF1 ≧ backup ring outer diameter φB> female side second diameter portion φF2.

  The refrigerant pipe 6 is inserted into the pipe insertion hole 92 and joined by brazing. The screw hole 93 is provided through the end portion of the female side joint 9, and a bolt 13 for fixing the male side joint 8 and the female side joint 9 at the time of connection is screwed thereto. Then, as shown in FIG. 2, the pipe joint 7 is configured such that the fitting convex portion 81 of the male joint 8 is fitted in the fitting concave portion 91 of the female joint 9, and the bolt 13 is tightened. The joint 8 and the female joint 9 are connected and fixed.

  Next, the outline | summary of the action | operation in this embodiment is demonstrated. When the refrigerant compressor 1 is activated, the high-temperature and high-pressure refrigerant compressed by the refrigerant compressor 1 is cooled by the refrigerant condenser 2 and decompressed by the expansion valve 3. The decompressed low-temperature and low-pressure refrigerant is evaporated by exchanging heat with the surrounding air in the refrigerant evaporator 4, and sucked into the refrigerant compressor 1 through the accumulator 5. These devices are connected by a refrigerant pipe 6 and connected by both ends of the refrigerant pipe 6 and the above-described pipe joint 7 provided in each device.

  Next, features in the present embodiment and actions by the features will be described. First, on the outer periphery of the backup ring 10, the ring outer taper surface 10 b inclined in the same direction as the ring inner taper surface 10 a and the ring outer taper surface at the position corresponding to the backup ring 10 of the sealed surface 91 a of the female joint 9 are provided. 10b, a female taper surface 91b corresponding to the male taper surface 81b and the inner taper surface αa of the ring inner taper surface 10a, and the outer taper surface βb of the ring outer taper surface 10b and female taper surface 91b, The inner taper angle α> the outer taper angle β> 0 degrees.

  According to this, by providing the ring outer taper surface 10b and the corresponding female side taper surface 91b, the outer peripheral side of the backup ring 10 is not a conventional fitting between the cylindrical surfaces, but the conical surfaces are inserted. The insertion force at the time of connection can be set because the final compression allowance can be set by the indentation dimension after insertion instead of inserting the predetermined compression allowance while compressing from the initial stage. Can be lowered.

  FIG. 3 is a partial cross-sectional view of the main part A in FIG. 2A. FIG. 3A is a connection halfway state, FIG. 3B is a connection completed state, and FIG. 3C is a state in which the inside is pressurized. Show. As shown in the figure, since the angle difference of the inner taper angle α> the outer taper angle β is provided, the shape of the backup ring 10 and the shape of the space that houses the backup ring 10 gradually decrease toward the non-pressurizing side. Due to the taper shape, when the internal pressure (refrigerant pressure) is applied, the backup ring 10 is driven into a wedge shape by the pushing force of the O-ring 11 to ensure a structure that improves the sealing performance (see FIG. 3C). .

  As a result, in the connecting device constituted by the sealing member 11 such as a rubber O-ring and the resin backup ring 10, the assembling property can be improved by reducing the insertion force at the time of connection without impairing the sealing property. . FIG. 4 is a cross-sectional view of the backup ring 10 of the present invention and a plan view from both sides. As shown in the figure, when the cross-sectional shape is tapered, a difference in shape between both surfaces is increased, and the direction can be easily confirmed, thereby preventing erroneous assembly. In addition, even after mounting on the fitting convex portion 81, the direction can be visually confirmed by the taper of the outer peripheral surface.

  5 is a partial cross-sectional view of the main part A in the case of separating the connecting device 7 of FIG. 2, (a) is a state in which there is a residual pressure before separation, (b) is a state in the middle of separation, (C) shows a state in which the inside is opened. As shown in the figure, during separation, the contact surface of the backup ring 10 gradually expands, and the internal gas remaining as the residual pressure gradually escapes. Therefore, stress applied to the worker performing the separation work Can be reduced.

  In addition, the inner diameter of the first cylindrical portion 91c on the outer side of the female side tapered surface 91b provided in the female side joint 9 is set to be the sealed surface on the inner side of the female first tapered portion 91F and the female side tapered surface 91b. The inner diameter of 91a is a female-side second diameter portion φF2, and these and the outer diameter φB of the backup ring 10 have a relationship of female-side first diameter portion φF1 ≧ backup-ring outer diameter φB> female-side second diameter portion φF2. Yes. As specific examples, φF1 = φ11.35, φB = φ11.3, and φF2 = φ10.75. According to this, the backup ring 10 can be inserted without being compressed, and the assemblability can be improved by reducing the insertion force at the time of connection.

  Further, the backup ring 10 is made of nylon resin (PA), more preferably nylon 1010 (PA1010). FIG. 6 is a graph comparing the ease of leakage due to the material of the backup ring 10 and the insertion force (hardness). As can be seen from the graph, nylon resin (PA6, PA11, PA66, PA612, etc.) is closest to the target values for easy leakage and insertion force (hardness), and the only nylon 1010 (PA1010) is easy to leak and insertion force (hardness). It satisfies the target value of and is the best. According to this, the refrigerant permeability can be reduced and the insertion property can be improved.

  Incidentally, the non-nylon resin compared in the graph of FIG. 6 is PVA (polyvinyl alcohol), EVOH (ethylene vinyl alcohol), PET (polyethylene terephthalate), PVC (polyvinyl chloride), PE (polyethylene), PP. (Polypropylene), PC (polycarbonate), PTFE (polytetrafluoroethylene).

  The gas is carbon dioxide. According to this, this embodiment is suitable for connection devices, such as a pipe joint which connects the refrigerant | coolant flow path of the refrigerating cycle which used the carbon dioxide gas with a high operating pressure and a large permeability coefficient as a refrigerant | coolant.

(Second Embodiment)
FIG. 7 is a partial cross-sectional view of the main part of the pipe joint 7 in the second embodiment of the present invention. As a feature different from the above-described embodiment, a vertical wall surface 81 </ b> C serving as a stopper shape of the backup ring 10 is provided on the large diameter side of the male taper surface 81 b. Thereby, even if the backup ring 10 is broken, it can be formed into a shape that does not come out to the outside.

(Other embodiments)
In the above-described embodiment, the connection device of the present invention is applied to a joint portion that connects flow paths such as pipes through which pressurized gas flows. However, the present invention is not limited to the above-described embodiment. Alternatively, the present invention may be applied to a seal between other members in contact with the gas, such as a container in which pressurized gas is sealed in addition to the connection portion and its lid.

  In addition to pipe joints that connect pipes, this connection device is applied to the connection part between piping and refrigeration equipment, or the connection part between refrigeration equipment (for example, the connection part between an evaporator and a box expansion valve). You may do it. Furthermore, the connection device according to the present invention may be used not only for connecting a carbon dioxide pipe in a cooling device, but also for sealing other gases by appropriately selecting a seal member and a backup ring material.

It is a schematic diagram of the refrigerating cycle R concerning embodiment of this invention. (A) is sectional drawing which shows the connection state of the piping joint 7 in 1st Embodiment of this invention, (b) is a fragmentary figure of the principal part A in (a), and shows the state before a connection, ( c) is an enlarged cross-sectional view of the backup ring 10. It is a fragmentary sectional view of the important section A in Drawing 2 (a), (a) is in the middle of connection, (b) is in the connection completion state, (c) shows the state where the inside was pressurized. It is sectional drawing of the backup ring 10 of this invention, and the top view from both sides. It is a fragmentary sectional view of the principal part A in the case of isolate | separating the pipe joint 7 of FIG. 2, (a) is a state with a residual pressure inside before separation, (b) is a state in the middle of separation, (c) is an internal Indicates the opened state. 4 is a graph comparing the ease of leakage due to the material of the backup ring 10 and the insertion force (hardness). It is a fragmentary sectional view of an important section of connecting device 7 in a 2nd embodiment of the present invention. (A) is sectional drawing which shows the connection state of the conventional connection apparatus 7, (b) is a fragmentary sectional view of the principal part A of the connection middle state. (A) is sectional drawing which shows the connection state of the conventional connection apparatus 7, (b) is a connection middle state, (c) is a fragmentary sectional view of the principal part A in the state where the inside was pressurized. It is a fragmentary sectional view by the side of the fitting convex part 81 explaining the other conventional problem. FIG. 9 is a partial cross-sectional view of a main part A in the case of separating the connecting device 7 of FIG. 8 (FIG. 9), (a) is a state in which there is a residual pressure before separation, (b) is a state in the middle of separation, c) shows the state at the moment when the interior is opened.

Explanation of symbols

8 ... Male side joint (Male side member)
8a ... flow path 9 ... female side joint (female side member)
9a ... Flow path 10 ... Backup ring 10a ... Ring inner taper surface 10b ... Ring outer taper surface 11 ... O-ring (seal member)
81 ... Fitting convex part 81a ... Seal surface 81b ... Male side taper surface 91a ... Seal surface 91b ... Female side taper surface 91c ... First cylindrical part PA ... Nylon resin PA1010 ... Nylon 1010
α ... Inner taper angle β ... Outer taper angle φB ... Outer diameter of backup ring φF1 ... Female-side first diameter portion φF2 ... Female-side second diameter portion

Claims (4)

A male side member (8) and a female side member (9), which are connected to each other with flow paths (8a, 9a) through which pressurized gas flows;
The male side member (8) has a fitting projection (81) formed in a cylindrical shape,
A seal member (11) which is mounted on the outer peripheral side of the fitting convex portion (81) and seals between the sealed surfaces (81a, 91a) of the male side and female side members (8, 9);
The seal member (11) that is formed of a material that is less permeable to gas than the seal member (11) and that receives a pressure difference between the inside and outside of the male side and female side members (8, 9). A backup ring (10) to support,
At the mounting position of the backup ring (10) of the fitting convex portion (81), the male taper surface (81b) in which the distance between the sealed surfaces (81a, 91a) gradually decreases toward the non-pressurized side of the gas. )
The inner diameter side of the backup ring (10) has a ring inner tapered surface (10a) corresponding to the male tapered surface (81b),
The male taper surface (81b) and the ring inner taper surface (10a) are arranged so that the back-up ring (10) pressed by the seal member (11) receiving the pressure difference is sealed with the surfaces to be sealed (81a, 91a). In the connecting device for preventing the gas flowing inside from being compressed by being compressed between the surfaces to be sealed (81a, 91a) and leaking outside,
A ring outer taper surface (10b) inclined in the same direction as the ring inner taper surface (10a) on the outer periphery side of the backup ring (10);
At the position corresponding to the backup ring (10) of the sealed surface (91a) of the female side member (9), a female side tapered surface (91b) corresponding to the ring outer tapered surface (10b) is provided,
An inner taper angle (α) of the male taper surface (81b) and the ring inner taper surface (10a), and an outer taper angle (β) of the ring outer taper surface (10b) and the female taper surface (91b). Is a relation of inner taper angle (α)> outer taper angle (β)> 0 degree.   The inner diameter of the first cylindrical portion (91c) on the outer side of the female taper surface (91b) provided on the female side member (9) is changed to the female first diameter portion (φF1), and the female taper surface ( 91b), the inner diameter of the surface to be sealed (91a) is the female second diameter portion (φF2), and the outer diameter (φB) of the backup ring (10) is the first on the female side. 2. The connection device according to claim 1, wherein a relation of a diameter part (φF1) ≧ a backup ring outer diameter (φB)> a female second diameter part (φF2) is established.   The connection device according to any one of claims 1 and 2, wherein the material of the backup ring (10) is nylon resin (PA), more preferably nylon 1010 (PA1010). The connection device according to any one of claims 1 to 3, wherein the gas is CO ₂ gas.

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