JP7078492B2 - Pipe fittings - Google Patents

Description

The present invention relates to a pipe joint including two pipe joint members that are detachably connected to each other, and more particularly, at least one pipe joint member has a metal sealing surface for fluid-sealing a fluid passage from the outside. Regarding pipe fittings.

In a pipe joint, a rubber O-ring is often used to seal the fluid between the pipe joint members at the time of connection and to fluid-seal the valve of the pipe joint member at the time of a single unit. However, in pipe joints used for pipes through which high-pressure or high-temperature fluids or fluids that are corrosive to rubber flow, rubber O-rings may not withstand the usage environment and may not be able to maintain sealing performance. Therefore, a fluid seal may be formed by a metal seal that directly contacts members made of a relatively hard material such as metal (Patent Document 1).

Japanese Unexamined Patent Publication No. 2006-105285

However, since the metal seal brings hard materials into contact with each other, there is a problem that if foreign matter such as dust is caught between them, a gap is formed between the sealing surfaces and an appropriate fluid sealing cannot be formed. In particular, when the pipe joint member is repeatedly attached and detached, the sealing surface is exposed and there is a high possibility that foreign matter adheres to the sealing surface.

Therefore, an object of the present invention is to provide a pipe joint in which even if a foreign substance adheres to the metal seal surface forming the metal seal, the foreign substance is removed before the metal seal is formed.

That is, the present invention
A pipe joint including a first pipe joint member and a second pipe joint member that are detachably connected to each other.
The first pipe joint member comprises a tubular first pipe joint body that defines a first fluid passage.
The second pipe joint member has a tubular second pipe joint body that defines a second fluid passage that communicates with the first fluid passage in the connected state with the first pipe joint member, and the second pipe joint member in the connected state. With an insertion part to be inserted into one fluid passage,
The first pipe joint member has a metal sealing surface for fluid-sealing the first fluid passage from the outside in at least one of a connected state and a disconnected state with the second pipe joint member.
The insertion portion provides a pipe joint including an elastic sliding member that slides on the metal seal surface when the first pipe joint member and the second pipe joint member are attached and detached.

In the pipe joint, an elastic sliding member is provided at the insertion portion of the second pipe joint member, and the metal of the first pipe joint member when the first pipe joint member and the second pipe joint member are attached and detached. The elastic sliding member slides on the sealing surface. This makes it possible to remove foreign matter such as dust and dirt adhering to the metal seal surface by the elastic sliding member.

The "metal seal" in the present specification is not necessarily limited to the contact between metals, but also the contact between relatively hard non-metal materials such as polyetheretherketone (PEEK) and the contact thereof. It shall also include the sealing provided by the contact between the non-metallic material and the metallic material. Therefore, the "metal seal surface" in the present application does not necessarily have to be a metal surface.

Specifically, the metal seal surface is an inner peripheral metal seal surface formed at the front end portion of the inner peripheral surface of the first pipe joint body defining the first fluid passage and expanding in diameter toward the front. The second pipe joint member has an outer peripheral metal seal surface formed on the outer peripheral surface of the insertion portion and having a diameter reduced toward the front of the second pipe joint member, and in the connected state, the inner peripheral metal seal surface. And the outer peripheral metal seal surface can be pressed and engaged with each other to form a fluid seal.

or,
The metal seal surface is an inner peripheral metal seal surface formed on the inner peripheral surface of the first pipe joint body that defines the first fluid passage and whose diameter is reduced toward the front.
The first pipe joint member includes a valve member arranged in the first fluid passage, and the valve member is formed on the outer peripheral surface of the valve member and has a diameter reduced toward the front of the first pipe joint member. It has a metal sealing surface on the outer circumference.
The valve member has a closing position in which the outer peripheral metal seal surface press-engages with the inner peripheral metal seal surface to form a fluid seal and closes the first fluid passage, and the press engagement is released and the first. Displaceable in the direction of the longitudinal axis of the first fluid passage from the open position where the fluid passage is opened.
When the valve member is in the closed position in the disconnected state and the first pipe joint member and the second pipe joint member are connected, the insertion portion presses the valve member and the valve member presses the valve member. It can be displaced to the open position.

In this case,
The second pipe joint member has a tubular outer valve member having a through-passage penetrating in the direction of the longitudinal axis, and the insertion portion is an inner valve member extending through the through-passage, and the elastic slide. The moving member is arranged on the outer peripheral surface of the inner valve member, and the moving member is arranged on the outer peripheral surface of the inner valve member.
The outer valve member is in a closed position where it is hermetically engaged with the elastic sliding member to close the gangway in the disengaged state, and is pressed by the first pipe joint member in the connected state to be hermetically sealed. The engagement can be disengaged to an open position that opens the gangway.

or,
The first pipe fitting member comprises a valve member disposed within the first fluid passage.
The metal seal surface has first and second inner peripheral metal seal surfaces formed on the inner peripheral surface of the first pipe joint body that defines the first fluid passage, and the first inner peripheral metal seal surface. The diameter is reduced toward the front, and the diameter of the second inner peripheral metal seal surface is expanded toward the front of the first pipe joint body at the position in front of the first inner peripheral metal seal surface.
The valve member has a first outer peripheral metal seal surface formed on the outer peripheral surface of the valve member and having a diameter reduced toward the front of the first pipe joint member.
The insertion portion has a second outer peripheral metal seal surface formed on the outer peripheral surface of the insertion portion and whose diameter is reduced toward the front of the second pipe joint member.
The valve member has a closing position in which the first outer peripheral metal seal surface press-engages with the first inner peripheral metal seal surface to form a fluid seal and closes the first fluid passage, and the press engagement is released. The first fluid passage is displaced in the direction of the longitudinal axis of the first fluid passage from the open position where the first fluid passage is opened.
When the valve member is in the closed position in the disconnected state and the first pipe joint member and the second pipe joint member are connected, the insertion portion presses the valve member and the valve member presses the valve member. It is designed to be displaced to the open position.
In the connected state, the second inner peripheral metal seal surface and the second outer peripheral metal seal surface are pressed and engaged with each other to form a fluid seal.
When the first pipe joint member and the second pipe joint member are attached to and detached from each other, the elastic sliding member can be made to slide on the first and second inner peripheral metal seal surfaces.

In this case further
The valve member is a tubular outer valve member having a gangway that penetrates in the direction of the longitudinal axis.
The first pipe fitting member extends through the gangway and further comprises an inner valve member having another elastic sliding member on its outer peripheral surface.
When the outer valve member is in the closed position, the outer valve member is hermetically engaged with the inner valve member to close the gangway, and when the outer valve member is in the open position, the hermetic engagement is released to open the gangway. Being
The second pipe joint body has a third inner peripheral metal seal surface on the inner peripheral surface of the second pipe joint body.
The second pipe joint member further includes a valve member arranged in the second fluid passage, and the valve member has a third outer peripheral metal sealing surface on the outer peripheral surface of the valve member, and the third outer peripheral surface thereof. The closed position where the metal seal surface is pressed and engaged with the third inner peripheral metal seal surface to form a fluid seal and close the second fluid passage, and the pressing engagement is released to open the second fluid passage. Displaceable in the direction of the longitudinal axis of the second fluid passage to and from the open position.
When the first pipe joint member and the second pipe joint member are connected, the valve member of the second pipe joint member is pressed against the inner valve member of the first pipe joint member to the open position. It is made to be displaced to
When the first pipe joint member and the second pipe joint member are attached to and detached from each other, the elastic sliding member of the inner valve member slides on the third inner peripheral metal seal surface. Can be done.

Furthermore,
The first pipe joint body has an intermediate inner peripheral surface formed between the first inner peripheral metal sealing surface and the second inner peripheral metal sealing surface.
When the first pipe joint member and the second pipe joint member are attached to and detached from each other, the elastic sliding member of the insertion portion is hermetically engaged with the intermediate inner peripheral surface on the intermediate inner peripheral surface. Can be made to slide.

The elastic sliding member can be made of a rubber O-ring.

Hereinafter, embodiments of the pipe joint according to the present invention will be described with reference to the accompanying drawings.

It is a side sectional view in the unconnected state (single state) of the pipe joint which concerns on one Embodiment of this invention. It is a figure which shows the 1st state in the process of connecting the pipe joint of FIG. It is a figure which shows the 2nd state in the process of connecting the pipe joint of FIG. It is a figure which shows the 3rd state in the process of connecting the pipe joint of FIG. It is a figure which shows the 4th state in the process of connecting the pipe joint of FIG. It is a figure which shows the connection state of the pipe joint of FIG. FIG. 6 is a diagram showing a state in which the spring holding member is in the sleeve fixing position in the connected state of FIG. It is an enlarged view of the peripheral part of the 2nd metal seal surface and the 2nd corresponding metal seal surface in the connected state. It is an enlarged view of the 2nd metal seal surface and the 2nd corresponding metal seal surface of the pipe joint which concerns on another Embodiment of this invention, and is the state which the 2nd metal seal surface and the 2nd corresponding metal seal surface are not in contact with each other. It is a figure of. 9 is an enlarged view of a second metal seal surface and a second corresponding metal seal surface of the pipe joint of FIG. 9, and is a view of a state in which the second metal seal surface and the second corresponding metal seal surface are in contact with each other.

As shown in FIG. 1, the pipe joint 1 according to an embodiment of the present invention includes a plug (first pipe joint member) 10 and a socket (second pipe joint member) 12 detachably connected to the plug 10. Consists of. As will be described later, the plug 10 and the socket 12 are each provided with a valve structure, and when the plug 10 and the socket 12 are connected, each valve structure is changed from the closed state to the open state.

The plug 10 has a tubular plug body (first pipe joint body) 20 having a fluid passage 18 extending from the front end opening 14 to the rear end opening 16, and an outer valve member 22 and an inner valve arranged in the fluid passage 18. A member 24 and a coil spring 26 for urging the outer valve member 22 and the inner valve member 24, respectively, are provided. The plug body 20 is composed of a front member 28 and a rear member 30 screwed to each other, and the end surface 28a of the front member 28 and the end surface 30a of the rear member 30 are pressed against each other to form a so-called metal seal, whereby the front member 28 is formed. And the rear member 30 are sealed. On the inner peripheral surface 20a of the plug main body 20, the first inner peripheral metal seal surface 32 whose diameter is reduced toward the front of the plug 10 (to the left in the figure) and the front end portion of the inner peripheral surface 20a are directed forward. A second inner peripheral metal seal surface 34 having an enlarged diameter is formed.

The outer valve member 22 is a through-passage that penetrates in the direction of the longitudinal axis L of the fluid passage (first fluid passage) 18 and the outer peripheral surface 22a on which the first outer peripheral metal seal surface 36 whose diameter is reduced toward the front is formed. It is a tubular member having an inner peripheral surface 22b that defines 38. The outer valve member 22 has a closing position (FIG. 1) in which the first outer peripheral metal seal surface 36 is pressed and engaged with the first inner peripheral metal seal surface 32 of the plug body 20 to form a metal seal in the fluid passage 18. , It is possible to displace in the direction of the longitudinal axis L from the closed position to the open position (FIGS. 5 to 7) where the pressing engagement is disengaged by being displaced rearward (to the right in the figure). When the outer valve member 22 is in the closed position, the outer peripheral surface 22a of the outer valve member 22 and the inner peripheral surface 20a of the plug main body 20 are fluid-sealed by a metal seal and closed.

The inner valve member 24 is arranged in the fluid passage 18 so that a part thereof is located in the through-passage 38 of the outer valve member 22. Further, the inner valve member 24 can be displaced with respect to the plug main body 20 in the direction of the longitudinal axis L. An annular elastic sealing member 40 that is hermetically engaged with the inner peripheral surface 22b of the outer valve member 22 is attached to the outer peripheral surface 24a of the inner valve member 24. In this embodiment, the elastic sealing member 40 is a rubber O-ring.

The coil spring 26 is a connecting portion 46 that radially connects the large diameter portion 42, the small diameter portion 44 located behind the large diameter portion 42, the rear end 42a of the large diameter portion 42, and the front end 44a of the small diameter portion 44. It consists of. The large diameter portion 42 is arranged around the outer valve member 22, and the small diameter portion 44 having a smaller diameter than the large diameter portion 42 is arranged around the inner valve member 24. As a result, the radial positions of the outer valve member 22 and the inner valve member 24 with respect to the plug body 20 are constrained. The position of the coil spring 26 with respect to the plug body 20 is fixed by engaging the connecting portion 46 with the locking step portion 48 formed on the inner peripheral surface 20a of the plug body 20. The first spring portion 42 composed of the large diameter portion 42 extends between the rear end 42a and the front end 42b engaged with the outer valve member 22, and causes the outer valve member 22 to move forward with respect to the plug body 20. I'm urging. The rear end 42a of the first spring portion 42 is connected to the connecting portion 46 locked to the locking step portion 48, and constitutes a stationary end 42a stationary with respect to the plug main body 20. On the other hand, the front end 42b of the first spring portion 42 constitutes a displacement end 42b that is displaced together with the outer valve member 22. Similarly, the second spring portion 44 composed of the small diameter portion 44 extends between the front end 44a and the rear end 44b engaged with the inner valve member 24, and the inner valve member 24 is rearward with respect to the plug body 20. Is urging. The front end 44a of the second spring portion 44 is connected to the connecting portion 46 locked to the locking step portion 48 to form a stationary end 44a stationary with respect to the plug body 20. On the other hand, the rear end 44b of the second spring portion 44 constitutes a displacement end 44b that is displaced together with the inner valve member 24. In the disconnected state of FIG. 1, the outer valve member 22 is urged forward by the first spring portion 42 to a closed position, and the inner valve member 24 is urged rearward by the second spring portion 44 to be an elastic sealing member. It is hermetically engaged with the outer valve member 22 via the 40 and closes the through-passage 38 of the outer valve member 22. That is, in the disconnected state, the fluid passage 18 of the plug 10 is closed by the outer valve member 22 and the inner valve member 24 respectively urged by the coil spring 26. When the outer valve member 22 and the inner valve member 24 are urged in opposite directions by the coil spring 26, there is a manufacturing dimensional error in each member, or the elastic sealing member 40 is used repeatedly. Even if it is deformed in, the sealing engagement between the first inner peripheral metal seal surface 32 and the first outer peripheral metal seal surface 36 and the elasticity between the outer valve member 22 and the inner valve member 24. Both sealing engagement via the sealing member 40 are properly performed. Since the urging force of the second spring portion 44 is set to be weaker than the urging force of the first spring portion 42, the outer valve member 22 attaches the first spring portion 42 only by the urging force of the second spring portion 44. It does not displace backward from the closed position against the forces.

The coil spring 26 for urging the outer valve member 22 and the inner valve member 24 of the plug 10 does not necessarily have to be configured as one member, and the first spring portion 42 for urging the outer valve member 22 The second spring portion 44 that urges the inner valve member 24 may be configured as a separate coil spring, and the stationary end of each spring portion may be locked to the plug body 20.

On the inner peripheral surface 20a of the plug main body 20, a retaining protrusion 49 protruding inward in the radial direction is formed at a position between the stationary end 44a and the displacement end 44b of the second spring portion 44 in the direction of the longitudinal axis L. ing. Further, the displacement end 44b of the second spring portion 44 has a larger diameter than the other portions of the second spring portion 44, and has an outer diameter larger than the inner diameter of the retaining protrusion 49. As described above, the inner valve member 24 is urged rearward by the second spring portion 44, but for example, the fluid pressure in the fluid passage 18 increases and the second spring portion 44 with respect to the inner valve member 24 When a forward force larger than the urging force of is applied, the inner valve member 24 is displaced forward from the position shown in FIG. In this case, the displacement end 44b of the second spring portion 44 engages with the retaining protrusion 49 to prevent the inner valve member 24 from being further displaced forward, and the inner valve member 24 is excessively displaced. Is prevented. Even when the inner valve member 24 is displaced forward, the connecting portion 46 of the coil spring 26 is still locked to the locking step portion 48 by the urging force of the first spring portion 42, and the first spring The part 42 is not compressed.

Further, on the inner peripheral surface 20a of the plug main body 20, a locking protrusion 50 protruding inward in the radial direction is formed at a position behind the retaining protrusion 49. Further, a locking projection 52 protruding outward in the radial direction is formed on the outer peripheral surface 24a of the inner valve member 24. As will be described later, when the outer valve member 22 is pushed backward, the inner valve member 24 is displaced rearward together with the outer valve member 22 by the urging force of the second spring portion 44, but the inner valve member 24 By engaging the locking projection 52 with the locking projection 50 of the plug body 20, the rearward displacement of the inner valve member 24 is restricted, and the inner valve member 24 is prevented from further rearward displacement. It has become.

The socket 12 has a tubular socket body (second pipe joint body) 60 defining a fluid passage (second fluid passage) 58 extending from the front end opening 54 to the rear end opening 56, and a longitudinal axis L in the fluid passage 58. The valve member 62 is provided so as to be displaceable in the direction of the above. The socket body 60 is composed of a front member 64 and a rear member 66 screwed to each other, and a second outer peripheral metal seal surface whose diameter is reduced toward the front (to the right in the figure) on the outer peripheral surface 66a of the rear member 66. 67 is formed, and a third inner peripheral metal seal surface 68 whose diameter is reduced toward the front is formed on the inner peripheral surface 66b. Further, a third outer peripheral metal seal surface 70 whose diameter is reduced toward the front is formed on the outer peripheral surface 62a of the valve member 62. The valve member 62 has a closing position (FIG. 1) in which the third outer peripheral metal sealing surface 70 is pressed and engaged with the third inner peripheral metal sealing surface 68 by the urging force of the valve spring 72 to form a fluid seal and close the fluid passage 58 (FIG. 1). ) And the open position (FIGS. 5 to 7) that displaces backward (to the left in the figure) from the closed position to release the pressing engagement and open the fluid passage 58. .. The valve member 62 is urged forward toward the closing position by the valve spring 72.

A plurality of lock holder holding holes 74 penetrating in the radial direction are provided in the front member 64 of the socket body 60, and a spherical locker 76 is arranged in each locker holding hole 74. Further, a sleeve 78 is arranged on the outer peripheral surface 60a of the socket main body 60. The sleeve 78 has a connecting position (FIGS. 1, 6 and 7) in which a part of the locker 76 is held at a locked position protruding radially inward from the inner peripheral surface 64a of the front member 64 of the socket body 60. It is possible to displace in the direction of the longitudinal axis L from the disengagement position (FIGS. 2 to 5) that is displaced rearward from the coupling position and allows the locker 76 to be displaced outward in the radial direction. A spring holding member 82 for holding the sleeve spring 80 in a compressed state is further mounted on the outer peripheral surface 60a of the socket body 60 with the sleeve 78. The sleeve 78 is urged forward toward the connecting position by the sleeve spring 80.

When connecting the plug 10 and the socket 12, the sleeve 78 is displaced rearward in the disconnected state shown in FIG. 1 to set the disconnection position, and then the plug 10 is inserted into the socket 12. Then, as shown in FIG. 2, the locker 76 is first pushed outward by the plug body 20 in the radial direction to reach the unlocked position. Further, the insertion portion 86 in which the valve pressing portion 84 of the socket main body 60 is formed is inserted inside the plug main body 20, and the elastic sliding member 88 made of a rubber O-ring attached to the insertion portion 86 is the plug main body. It abuts on the second inner peripheral metal seal surface 34 of 20. Further, when the plug 10 is further inserted into the socket 12, as shown in FIG. 3, the elastic sliding member 88 slides on the second inner peripheral metal seal surface 34 while being crushed by the second inner peripheral metal seal surface 34. To go. Further, the valve pressing portion 84 of the socket 12 abuts on the outer valve member 22 of the plug 10, and the valve member 62 of the socket 12 abuts on the inner valve member 24 of the plug 10. Further, when the plug 10 is further inserted into the socket 12, as shown in FIG. 4, the outer valve member 22 of the plug 10 is displaced rearward (to the right in the figure) by the valve pressing portion 84 of the socket 12, and the first inner is inserted. The metal seal between the peripheral metal seal surface 32 and the first outer peripheral metal seal surface 36 is released. At this time, the inner valve member 24 urged rearward by the second spring portion 44 of the coil spring 26 is also displaced rearward. The inner valve member 24 is displaced rearward together with the outer valve member 22 to a position where the locking projection 52 abuts on the locking projection 50 of the plug body 20, and thereafter, only the outer valve member 22 is displaced rearward. As a result, the sealing engagement between the inner valve member 24 and the outer valve member 22 via the elastic sealing member 40 is released. Further, the valve member 62 of the socket 12 is pushed by the inner valve member 24 of the plug 10 and displaced rearward (to the left in the figure) to form the third inner peripheral metal sealing surface 68 and the third outer peripheral metal sealing surface 70. The metal seal between them is also released. In the state of FIG. 4, the metal seal on the first inner peripheral metal seal surface 32 is released, but the first inner peripheral metal seal surface 32 and the second inner peripheral metal seal surface 34 of the plug main body 20 are formed. The elastic sliding member 88 is hermetically engaged with the intermediate inner peripheral surface 90 between them, and the fluid passage 18 of the plug 10 is maintained in a fluid-sealed state with respect to the outside. Further, the inner valve member 24 of the plug 10 is inserted inside the socket body 60, and the elastic sealing member 40 attached to the inner valve member 24 is hermetically engaged with the inner peripheral surface 66b of the rear member 66 of the socket body 60. , The fluid passage 18 of the plug 10 and the fluid passage 58 of the socket 12 are not yet in communication. Further, when the plug 10 is further inserted into the socket 12, as shown in FIG. 5, the outer valve member 22 is displaced rearward while further compressing the first spring portion 42 of the coil spring 26 to be in the open position. The elastic sliding member 88 slides on the intermediate inner peripheral surface 90, exceeds the intermediate inner peripheral surface 90, reaches the first inner peripheral metal seal surface 32, and further slides on the first inner peripheral metal seal surface 32. Move. Further, the second inner peripheral metal sealing surface 34 of the plug main body 20 comes into contact with the second outer peripheral metal sealing surface 67 of the socket main body 60. The inner valve member 24 is further inserted into the socket body 60 and further pushes the valve member 62 of the socket 12 rearward to displace it to the open position. As a result, the sealing engagement between the elastic sealing member 40 and the inner peripheral surface 66b of the rear member 66 of the socket body 60 is released, and the fluid passage 18 of the plug 10 and the fluid passage 58 of the socket 12 communicate with each other. It becomes. When the force holding the sleeve 78 in the unlocked position is released in this state, the sleeve 78 is displaced forward to the connecting position by the urging force of the sleeve spring 80 and tilted as shown in FIG. The locker 76 is pressed inward in the radial direction by the locker pressing surface 94. The locker 76 pressed inward in the radial direction is partially pushed into the locker locking groove 96 formed on the outer peripheral surface 20b of the plug body 20. The sleeve 78 is urged forward by the sleeve spring 80 even at the connecting position, and the locker 76 receives a force in the radial direction from the inclined locker pressing surface 94. The front side surface 96a of the locker locking groove 96 is inclined so as to expand in diameter toward the front, and the locker 76 is pressed against the front side surface 96a. Therefore, the plug main body 20 receives a force in the direction of being pulled into the socket main body 60 (to the left in the figure) by the locker 76 pressed inward in the radial direction. As a result, the second inner peripheral metal seal surface 34 of the plug 10 is pressed and engaged with the second outer peripheral metal seal surface 67 of the socket 12 to form a metal seal with the second outer peripheral metal seal surface 67, and the plug is formed. A fluid seal is provided between the main body 20 and the socket main body 60. In this way, the pipe joint 1 is in a connected state.

In the connected state of FIG. 6, the elastic sliding member 88 and the elastic sealing member 40 made of the rubber material are both located in the fluid passages 18 and 58, and become a fluid flowing in the fluid passages 18 and 58. It is becoming exposed. Examples of the fluid flowing in the fluid passages 18 and 58 include a high-temperature organic heat medium, and the organic heat medium may oxidize and solidify when it comes into contact with air. In the pipe joint 1, the elastic sliding member 88 and the elastic sealing member 40 are located in the fluid passages 18 and 58 and are not exposed to air in the connected state. Therefore, the elastic sliding member 88 is not exposed to air. It is possible to prevent the organic heat medium adhering to the elastic sealing member 40 from solidifying.

In the connected state of FIG. 6, the connection between the plug 10 and the socket 12 is basically not released unless the sleeve 78 is operated so as to be displaced to the connection release position. However, when an excessive force is applied between the plug 10 and the socket 12 in the direction of pulling them apart from each other, the locker 76 is displaced outward in the radial direction due to the force received from the front side surface 96a of the locker locking groove 96. At the same time, the sleeve 78 may be displaced rearward to break the connection between the plug 10 and the socket 12. Further, even if the connection is not released, the metal seal between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 may be released and the internal fluid may leak to the outside. be. In order to prevent such a situation from occurring, in the pipe joint 1, the spring holding member 82 that holds the sleeve spring 80 that urges the sleeve 78 forward from the rear is in the direction of the longitudinal axis L. The position of is adjustable. Specifically, the spring holding member 82 is screwed with respect to the socket body 60, and the spring holding member 82 can be displaced in the direction of the longitudinal axis L by rotating the spring holding member 82 around the longitudinal axis L. It has become like. As shown in FIG. 7, by displacing the spring holding member 82 forward, the amount of compression of the sleeve spring 80 in the connected state is increased, and the locker 76 is pressed inward in the radial direction with a larger force via the sleeve 78. Will be done. As a result, the plug body 20 is pulled in with a larger force, the pressing force between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 becomes larger, and the metal sealing becomes stronger. Further, it is less likely that the connection between the plug 10 and the socket 12 will be released due to the force in the direction of separating the plug 10 and the socket 12 generated by the pressure of the internal fluid or the like. Further, by setting the spring holding member 82 at the sleeve fixing position where the front end contact portion 82a abuts on the stepped receiving portion 78a of the sleeve 78, the sleeve 78 cannot be displaced rearward toward the disconnection release position. Therefore, it is possible to prevent unexpected disconnection more reliably. The spring holding member 82 may not be screwed into the socket body 60 at the position shown in FIG. 6 but may be slidable in the direction of the longitudinal axis L, and may be screwed only near the position shown in FIG. 7. By doing so, it becomes possible to quickly perform the operation of setting the spring holding member 82 at the position shown in FIG. 7.

When disconnecting the plug 10 and the socket 12, the sleeve 78 is displaced to the disconnection position and then the plug 10 is pulled out from the socket 12. As a result, the connection between the plug 10 and the socket 12 is released, and the pipe joint 1 returns to the non-connected state shown in FIG.

When the plug 10 and the socket 12 are connected to each other, the pipe joint 1 is displaced from the closed position to the open position by pushing the outer valve member 22 of the plug 10 by the valve pressing portion 84 of the socket 12, and the outer valve member 22. And the inner valve member 24 are designed to release the closure of the fluid passage 18. In the pipe joint 1, only the first spring portion 42 urging the outer valve member 22 is compressed, and the second spring portion 44 urging the inner valve member 24 is not compressed.

In the pipe joint 1, when the plug 10 and the socket 12 are attached and detached, the elastic sliding member 88 attached to the insertion portion 86 of the socket body 60 is placed on the first inner peripheral metal seal surface 32 of the plug body 20. And it is designed to slide on the second inner peripheral metal seal surface 34. As a result, foreign matter such as dust and dirt adhering to the first inner peripheral metal sealing surface 32 and the second inner peripheral metal sealing surface 34 can be removed. Similarly, the elastic sealing member (elastic sliding member) 40 attached to the inner valve member (insertion portion) 24 of the plug 10 slides on the third inner peripheral metal seal surface 68 of the socket body 60. , Foreign matter such as dust and dirt adhering to the third inner peripheral metal seal surface 68 can be removed. In the metal seal, relatively hard members are brought into direct contact with each other for sealing engagement, so that a small amount of foreign matter adhering to the sealing surface may greatly affect the sealing property and prevent proper sealing. However, since the pipe joint 1 is designed to remove foreign matter adhering to the first to third inner peripheral metal seal surfaces 32, 34, 68 at the time of attachment / detachment as described above, an appropriate metal seal is provided by the foreign matter. It is possible to prevent the problem from becoming impossible.

As shown in FIG. 8, both the second inner peripheral metal sealing surface 34 of the plug main body 20 and the second outer peripheral metal sealing surface 67 of the socket main body 60 are inclined by an inclination angle θ with respect to the longitudinal axis L. The plug body 20 and the socket body 60 are made of materials having different coefficients of thermal expansion, and in the embodiment, the plug body 20 is formed of SUS310 (coefficient of thermal expansion: 14.4 × ^10-6 ). The socket body 60 is formed of SUS304 (coefficient of thermal expansion: 16.7 × ^10-6 ). Since the coefficient of thermal expansion of the plug body 20 located on the outside is smaller than the coefficient of thermal expansion of the socket body 60 located on the inside, a high-temperature fluid flows through the pipe joint 1 and the plug body 20 and the socket body 60 are used. When and is heated, the inner socket body 60 expands more. Due to the difference in the amount of expansion due to heating in this way, the pressing force between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 becomes larger with thermal expansion.

Here, assuming that the radial force acting between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 is W, the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface The force F in the direction along 67 and the force N in the direction perpendicular to it are as follows.
F = Wsinθ
N = Wcosθ
Further, assuming that the coefficient of static friction between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 is μ, the space between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 The maximum static friction force F _max is as follows.
F _max = μN
= ΜWcosθ
From these, the conditions for preventing slippage between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 due to the radial force W generated by the thermal expansion are obtained as follows.
F ≤ F _max
Wsinθ≤μWcosθ
tan θ ≤ μ

In the pipe joint 1, the static friction coefficient μ and the inclination angle θ are set so as to satisfy the relationship of tan θ ≦ μ. Specifically, the inclination angle θ is 6 ° (tan θ = 0.105), and the coefficient of static friction μ between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 is approximately 0. It is .2. Therefore, even if the pressing force between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 increases due to thermal expansion, the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 Are held together by friction and do not slip. That is, the plug main body 20 and the socket main body 60 are not relatively displaced in the direction of the longitudinal axis L due to thermal expansion, and the push between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67. The pressure increases with thermal expansion. Therefore, the metal seal between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 becomes stronger with thermal expansion.

The materials forming the plug body 20 and the socket body 60 can be appropriately changed according to the usage environment. For example, in a pipe joint for flowing a cooling material having a temperature lower than room temperature, the outer plug body 20 may be used. By selecting the material so that the coefficient of thermal expansion is larger than the coefficient of thermal expansion of the inner socket body 60, the amount of heat shrinkage of the plug body 20 is made larger than the amount of heat shrinkage of the socket body 60. When the plug body 20 and the socket body 60 are cooled, the pressing force between the second inner peripheral metal sealing surface 34 and the second outer peripheral metal sealing surface 67 may be increased. Further, the relationship between the first inner peripheral metal sealing surface 32 and the first outer peripheral metal sealing surface 36, and the relationship between the third inner peripheral metal sealing surface 68 and the third outer peripheral metal sealing surface 70 satisfies the above conditions. It may be set as follows.

In the pipe joint 101 according to another embodiment of the present invention, as shown in FIG. 9, an annular groove 198 is formed in the second inner peripheral metal seal surface 134, and the annular groove 198 is formed of a rubber material. An elastic sealing member 199 is provided. In the pipe joint 101, the elastic sealing member 199 is hermetically engaged with the second outer peripheral metal sealing surface 167 when the connected state is as shown in FIG. 7, and the second inner peripheral metal sealing surface 134 is still the second outer peripheral. Not engaged with the metal seal surface 167. When the pipe joint 101 is heated by flowing a high-temperature fluid or the like, the space between the second inner peripheral metal sealing surface 134 and the second outer peripheral metal sealing surface 167 gradually narrows due to the above-mentioned difference in the amount of thermal expansion. Eventually, as shown in FIG. 10, the second inner peripheral metal seal surface 134 and the second outer peripheral metal seal surface 167 engage with each other to form a metal seal. Alternatively, as shown in FIG. 8, the spring holding member 82 is displaced to the sleeve fixing position to increase the force applied by the sleeve 78 to the plug body 20 via the locker 76, so that the second inner portion is as shown in FIG. It is also possible to engage the peripheral metal seal surface 134 and the second outer peripheral metal seal surface 167 to form a metal seal. The elastic sealing member 199 may be provided on the side of the second outer peripheral metal sealing surface 167.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments. For example, in the above embodiment, the elastic sliding member 88 provided in the insertion portion 86 slides on both the first inner peripheral metal seal surface and the second inner peripheral metal seal surface. Only one metal seal surface may be slid. Further, the elastic sealing member 40 provided on the inner valve member 24 as the insertion portion also functions as an elastic sliding member sliding on the third inner peripheral metal seal surface, but it is not always the case. It is not necessary to do so, and an elastic sliding member different from the elastic sealing member 40 may be provided. Further, the elastic sliding member may slide on only one or two of the first to third metal seal surfaces. Further, the first pipe joint member may be configured as a socket, and the second pipe joint member may be configured as a plug.

1 pipe fitting 10 plug (first pipe fitting member)
12 socket (second pipe fitting member)
14 Front end opening 16 Rear end opening 18 Fluid passage (first fluid passage)
20 Plug body (1st pipe joint body)
20a Inner peripheral surface 20b Outer peripheral surface 22 Outer valve member 22a Outer peripheral surface 22b Inner peripheral surface 24 Inner valve member (insertion part)
24a Outer peripheral surface 26 Coil spring 28 Front member 28a End surface 30 Rear member 30a End surface 32 First inner peripheral metal sealing surface 34 Second inner peripheral metal sealing surface 36 First outer peripheral metal sealing surface 38 Through path 40 Elastic sealing member (elastic sliding) Element)
42 Large diameter part, 1st spring part 42a rear end, stationary end 42b front end, displacement end 44 small diameter part, 2nd spring part 44a front end, stationary end 44b rear end, displacement end 46 connecting part 48 locking step part 49 retaining Protrusion 50 Locking protrusion 52 Locking protrusion 54 Front end opening 56 Rear end opening 58 Fluid passage (second fluid passage)
60 Socket body (second pipe joint body)
60a Outer peripheral surface 62 Valve member 62a Outer peripheral surface 64 Front member 64a Inner peripheral surface 66 Rear member 66a Outer peripheral surface 66b Inner peripheral surface 67 Second outer peripheral metal seal surface 68 Third inner peripheral metal seal surface 70 Third outer peripheral metal seal surface 72 Valve Spring 74 Locker holding hole 76 Locker 78 Sleeve 78a Receiving part 80 Sleeve spring 82 Spring holding member 82a Front end contact part 84 Valve pressing part 86 Inserting part 88 Elastic sliding member 90 Intermediate inner peripheral surface 94 Locker pressing surface 96 Locking Child locking groove 96a Front side surface 101 Pipe fitting 134 Second inner peripheral metal sealing surface 167 Second outer peripheral metal sealing surface 198 Circular groove 199 Elastic sealing member L Longitudinal axis

Claims (8)

A pipe joint including a first pipe joint member and a second pipe joint member that are detachably connected to each other.
The first pipe joint member comprises a tubular first pipe joint body that defines a first fluid passage.
The second pipe joint member has a tubular second pipe joint body that defines a second fluid passage that communicates with the first fluid passage in the connected state with the first pipe joint member, and the second pipe joint member in the connected state. With an insertion part to be inserted into one fluid passage,
The first pipe joint member has a metal sealing surface for fluid-sealing the first fluid passage from the outside in at least one of a connected state and a disconnected state with the second pipe joint member.
A pipe joint comprising an elastic sliding member that slides on the metal seal surface when the first pipe joint member and the second pipe joint member are attached to and detached from the insertion portion. The metal seal surface is an inner peripheral metal seal surface formed at the front end portion of the inner peripheral surface of the first pipe joint body defining the first fluid passage and expanding in diameter toward the front, and is the second pipe joint. The member has an outer peripheral metal seal surface formed on the outer peripheral surface of the insertion portion and whose diameter is reduced toward the front of the second pipe joint member, and in the connected state, the inner peripheral metal seal surface and the outer peripheral metal seal. The pipe fitting according to claim 1, wherein the surfaces are pressed and engaged with each other to form a fluid seal. The metal seal surface is an inner peripheral metal seal surface formed on the inner peripheral surface of the first pipe joint body that defines the first fluid passage and whose diameter is reduced toward the front.
The first pipe joint member includes a valve member arranged in the first fluid passage, and the valve member is formed on the outer peripheral surface of the valve member and has a diameter reduced toward the front of the first pipe joint member. It has a metal sealing surface on the outer circumference.
The valve member has a closing position in which the outer peripheral metal seal surface press-engages with the inner peripheral metal seal surface to form a fluid seal and closes the first fluid passage, and the press engagement is released and the first. Displaceable in the direction of the longitudinal axis of the first fluid passage from the open position where the fluid passage is opened.
When the valve member is in the closed position in the disconnected state and the first pipe joint member and the second pipe joint member are connected, the insertion portion presses the valve member and the valve member presses the valve member. The pipe fitting according to claim 1, which is configured to be displaced to the open position. The second pipe joint member has a tubular outer valve member having a through-passage penetrating in the direction of the longitudinal axis, and the insertion portion is an inner valve member extending through the through-passage, and the elastic slide. The moving member is arranged on the outer peripheral surface of the inner valve member, and the moving member is arranged on the outer peripheral surface of the inner valve member.
The outer valve member is in a closed position where it is hermetically engaged with the elastic sliding member to close the gangway in the disengaged state, and is pressed by the first pipe joint member in the connected state to be hermetically sealed. The pipe joint according to claim 3, wherein the engagement is disengaged and the through-passage is opened to an open position. The first pipe fitting member comprises a valve member disposed within the first fluid passage.
The metal seal surface has first and second inner peripheral metal seal surfaces formed on the inner peripheral surface of the first pipe joint body that defines the first fluid passage, and the first inner peripheral metal seal surface. The diameter is reduced toward the front, and the diameter of the second inner peripheral metal seal surface is expanded toward the front of the first pipe joint body at the position in front of the first inner peripheral metal seal surface.
The valve member has a first outer peripheral metal seal surface formed on the outer peripheral surface of the valve member and having a diameter reduced toward the front of the first pipe joint member.
The insertion portion has a second outer peripheral metal seal surface formed on the outer peripheral surface of the insertion portion and whose diameter is reduced toward the front of the second pipe joint member.
The valve member has a closing position in which the first outer peripheral metal seal surface press-engages with the first inner peripheral metal seal surface to form a fluid seal and closes the first fluid passage, and the press engagement is released. The first fluid passage is displaced in the direction of the longitudinal axis of the first fluid passage from the open position where the first fluid passage is opened.
When the valve member is in the closed position in the disconnected state and the first pipe joint member and the second pipe joint member are connected, the insertion portion presses the valve member and the valve member presses the valve member. It is designed to be displaced to the open position.
In the connected state, the second inner peripheral metal seal surface and the second outer peripheral metal seal surface are pressed and engaged with each other to form a fluid seal.
A claim that the elastic sliding member slides on the first and second inner peripheral metal seal surfaces when the first pipe joint member and the second pipe joint member are attached to and detached from each other. The pipe fitting according to 1. The valve member is a tubular outer valve member having a gangway that penetrates in the direction of the longitudinal axis.
The first pipe fitting member extends through the gangway and further comprises an inner valve member having another elastic sliding member on its outer peripheral surface.
When the outer valve member is in the closed position, the outer valve member is hermetically engaged with the inner valve member to close the gangway, and when the outer valve member is in the open position, the hermetic engagement is released to open the gangway. Being
The second pipe joint body has a third inner peripheral metal seal surface on the inner peripheral surface of the second pipe joint body.
The second pipe joint member further includes a valve member arranged in the second fluid passage, and the valve member has a third outer peripheral metal sealing surface on the outer peripheral surface of the valve member, and the third outer peripheral surface thereof. The closed position where the metal seal surface is pressed and engaged with the third inner peripheral metal seal surface to form a fluid seal and close the second fluid passage, and the pressing engagement is released to open the second fluid passage. Displaceable in the direction of the longitudinal axis of the second fluid passage to and from the open position.
When the first pipe joint member and the second pipe joint member are connected, the valve member of the second pipe joint member is pressed against the inner valve member of the first pipe joint member to the open position. It is made to be displaced to
When the first pipe joint member and the second pipe joint member are attached to and detached from each other, the elastic sliding member of the inner valve member is made to slide on the third inner peripheral metal seal surface. , The pipe fitting according to claim 5. The first pipe joint body has an intermediate inner peripheral surface formed between the first inner peripheral metal sealing surface and the second inner peripheral metal sealing surface.
When the first pipe joint member and the second pipe joint member are attached to and detached from each other, the elastic sliding member of the insertion portion is hermetically engaged with the intermediate inner peripheral surface on the intermediate inner peripheral surface. The pipe fitting according to claim 5 or 6, which is made to slide. The pipe fitting according to any one of claims 1 to 7, wherein the elastic sliding member is a rubber O-ring.

Images