JP7178212B2 - pipe joint member - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pipe fitting member that is detachably coupled to a corresponding pipe fitting member, and more particularly to a pipe fitting member that includes a spring-biased valve member.

A pipe joint member that is detachably connected to a corresponding pipe joint member, and is provided with a valve member to prevent the fluid inside the fluid passage from leaking to the outside even in a single state that is not connected to the corresponding pipe joint member. be. There are various structures of the valve member, for example, an outer valve member that slides against the inner peripheral surface of the pipe fitting body in the fluid passage defined by the tubular pipe fitting body, and the outer valve member. an inner valve member disposed so as to pass through the through passage, the outer peripheral surface of the outer valve member sealingly engaging the inner peripheral surface of the pipe joint body, and the inner peripheral surface of the outer valve member sealingly engaging the outer peripheral surface of the inner valve member. The fluid passage is closed by sealing engagement with the outer valve member, and the fluid passage is opened by displacing the outer valve member with respect to the inner valve member to release the sealing engagement. In a pipe joint member comprising such an outer valve member and an inner valve member, the outer valve member is biased forward by a coil spring set between the outer valve member and the pipe joint main body, as disclosed in Patent Document 1, for example. The inner valve member is biased rearwardly against the outer valve member by a coil spring set between the inner valve member and the outer valve member. As a result, the inner valve member is biased by the coil spring even if the inner valve member has a dimensional error in manufacturing or changes in the shape of the seal member due to being exposed to a high-temperature environment. Since it is pressed against the outer valve member, it is possible to reliably close the fluid passage. Further, the corresponding pipe joint member has a valve pressing portion for pressing the outer valve member rearward, and the outer valve member is pushed rearward by the valve pressing portion when connecting the pipe joint member to the corresponding pipe joint member. It is designed to be Therefore, when the pipe joint member is connected to the corresponding pipe joint member, the outer valve member is displaced against the urging force of the coil spring to open the fluid passage of the pipe joint member.

JP-A-9-329286

In the pipe joint member as described above, when the outer valve member is displaced rearward to open the fluid passage, the coil spring set between the outer valve member and the pipe joint main body and the inner valve member Both the outer valve member and the coil spring set between them must be compressed. Therefore, when connecting, the pipe joint member is connected to the corresponding pipe joint member while compressing the two coil springs, which increases the load required for the connecting operation.

Accordingly, the present invention provides a pipe joint member comprising an outer valve member and an inner valve member, and a load required to open a fluid passage while sufficiently ensuring sealing between the outer valve member and the inner valve member. It is an object of the present invention to provide a pipe joint member capable of reducing the

That is, the present invention
A pipe joint member detachably connected to a corresponding pipe joint member,
a tubular fitting body having a front end opening, a rear end opening, and a fluid passageway extending from the front end opening to the rear end opening;
an outer peripheral surface disposed within the fluid passageway and provided with a sealing engagement portion for sealing engagement with the inner peripheral surface of the fitting body; a cylindrical outer valve member having a peripheral surface, wherein the sealing engagement portion sealingly engages the inner peripheral surface of the pipe fitting body to provide a gap between the outer peripheral surface and the inner peripheral surface of the pipe fitting body; an outer valve member displaceable in the direction of the longitudinal axis between a closed position that closes the valve member and an open position that displaces rearwardly from the closed position to disengage the sealing engagement;
an inner valve member disposed within the fluid passageway and at least partially within the through passage of the outer valve member and displaceable in the direction of the longitudinal axis;
extending between a stationary end stationary relative to the fitting body and a displaceable end engaging and displacing with the outer valve member to move the outer valve member forward relative to the fitting body; a first spring portion biasing the outer valve member into the closed position;
extending between a stationary end stationary relative to the fitting body and a displacement end engaging and displacing with the inner valve member to move the inner valve member rearwardly relative to the fitting body. a biasing second spring portion;
with
the second spring portion has a weaker biasing force than the first spring portion;
wherein, when the outer valve member is in the closed position, the inner valve member sealingly engages the outer valve member by the biasing force of the second spring portion to close the through passage. provide parts.

In the pipe joint member, the second spring portion for biasing the inner valve member rearward has a stationary end stationary with respect to the pipe joint body and a displacement end engaged with the inner valve member. Since the valve member is biased rearwardly with respect to the pipe joint main body, when the outer valve member biased forwardly by the first spring portion is displaced from the closed position to the open position, the second spring portion is not compressed and only the first spring portion becomes compressed. That is, when opening the fluid passage, it is not necessary to compress two springs as in the above-described conventional pipe joint member, and it is sufficient to compress only the first spring portion that biases the outer valve member. Therefore, the load required to open the fluid passage can be made smaller than in the conventional case.

Preferably, a large-diameter portion forming the first spring portion, a small-diameter portion positioned behind the large-diameter portion and forming the second spring portion, the small-diameter portion being smaller in diameter than the large-diameter portion, and the large-diameter portion A coil spring having a connecting portion radially connecting the stationary end of the first spring portion, which is the rear end, and the stationary end of the second spring portion, which is the front end of the small diameter portion, wherein the connecting portion is A coil spring locked to the pipe joint body may be provided.

By forming the first spring portion and the second spring portion from one coil spring in this way, it is possible to simplify the structure of the pipe joint member and to simplify the assembly work. Become.

Preferably, the large diameter portion of the coil spring is positioned around the outer valve member and the small diameter portion is positioned around the inner valve member, the coil spring pressing the outer valve member and the fitting body against the fitting body. A radial position of the inner valve member may be maintained.

More preferably, the inner peripheral surface of the pipe joint body has a retainer projection protruding radially inward at a position between the stationary end and the displaceable end of the second spring portion in the direction of the longitudinal axis. the displaced end of the second spring portion has an outer diameter larger than the inner diameter of the retaining protrusion,
When the inner valve member is displaced forward, the displacing end of the second spring portion engages with the retaining projection to prevent further forward displacement of the inner valve member. be able to.

The inner valve member is pushed forward by the pressure received from the internal fluid in the fluid passage, and is displaced forward when the pressure exceeds the biasing force of the second spring portion. However, in this configuration, when the inner valve member is displaced forward, the displacing end of the second spring portion engages the retainer protrusion to prevent the inner valve member from being displaced forward. It is possible to prevent a large amount of internal fluid from leaking to the outside due to excessive forward displacement.

Preferably, the inner peripheral surface of the pipe joint body protrudes radially inward so that when the inner valve member is displaced rearward, the inner valve member is engaged to further displace the inner valve member rearward. and the outer valve member is displaced rearward relative to the inner valve member engaged with the locking protrusion to close the through passage by the inner valve member. can be set to be released.

The present invention further provides
A pipe joint comprising any one of the pipe joint members described above and a corresponding pipe joint member detachably connected to the pipe joint member,
The corresponding pipe joint member includes a valve pressing portion that is inserted into the fluid passage of the pipe joint member when the pipe joint member and the corresponding pipe joint member are connected, and the valve pressing portion To provide a pipe joint adapted to displace the outer valve member to the open position while pressing the valve member to compress the first spring portion.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a pipe joint member and a pipe joint according to the present invention will be described based on the accompanying drawings.

1 is a side cross-sectional view of a pipe joint in an unconnected state (single state) according to an embodiment of the present invention; FIG. FIG. 2 is a view showing a first state in the middle of connecting the pipe joint of FIG. 1; FIG. 3 is a view showing a second state in the middle of connecting the pipe joint of FIG. 1; 1. It is a figure which shows the 3rd state in the middle of connection of the pipe joint of FIG. It is a figure which shows the 4th state in the middle of connection of the pipe joint of FIG. It is a figure which shows the connection state of the pipe joint of FIG. FIG. 7 is a diagram of a state in which a spring holding member is in a sleeve fixing position in the connected state of FIG. 6; 4 is an enlarged view of the periphery of the second metal seal face and the second corresponding metal seal face in the connected state; FIG. FIG. 5 is an enlarged view of a second metal seal surface and a second corresponding metal seal surface of a pipe joint according to another embodiment of the present invention, in a state where the second metal seal surface and the second corresponding metal seal surface are not in contact; is a diagram. FIG. 10 is an enlarged view of the second metal seal surface and the second corresponding metal seal surface of the pipe joint of FIG. 9, showing a state in which the second metal seal surface and the second corresponding metal seal surface are in contact with each other;

A pipe joint 1 according to an embodiment of the present invention comprises a plug (pipe joint member) 10 and a socket (corresponding pipe joint member) 12 detachably connected to the plug 10, as shown in FIG. As will be described later, the plug 10 and the socket 12 are each provided with a valve structure such that each valve structure changes from a closed state to an open state when the plug 10 and the socket 12 are connected.

The plug 10 includes a tubular plug body (fitting body) 20 having a fluid passageway 18 extending from a front end opening 14 to a rear end opening 16, an outer valve member 22 and an inner valve member 24 disposed within the fluid passageway 18. and a coil spring 26 biasing the outer valve member 22 and the inner valve member 24, respectively. The plug body 20 consists of a front member 28 and a rear member 30 which are screwed together, and the front member 28 is closed by pressing against each other an end face 28a of the front member 28 and an end face 30a of the rear member 30 to form a so-called metal seal. and the rear member 30 are sealed. The inner peripheral surface 20a of the plug body 20 includes a first inner peripheral metal seal surface 32 whose diameter is reduced toward the front of the plug 10 (to the left in the drawing), and a front end portion of the inner peripheral surface 20a which is oriented forward. A second inner peripheral metal seal surface 34 having an enlarged diameter is formed.

The outer valve member 22 has an outer peripheral surface 22a formed with a first outer peripheral metal seal surface (sealing engagement portion) 36 whose diameter is reduced toward the front, and a through passage penetrating in the direction of the longitudinal axis L of the fluid passage 18. It is a tubular member having an inner peripheral surface 22b that defines a diameter 38. As shown in FIG. The outer valve member 22 has a closed position (FIG. 1) in which the first outer peripheral metal sealing surface 36 is pressed against the first inner peripheral metal sealing surface 32 of the plug body 20 to form a metal seal in the fluid passage 18 . , and an open position (FIGS. 5 to 7) where the pressing engagement is released by displacing rearward (rightward in the drawing) from the closed position in the direction of the longitudinal axis L. When the outer valve member 22 is in the closed position, the fluid seal between the outer peripheral surface 22a of the outer valve member 22 and the inner peripheral surface 20a of the plug body 20 is fluid-tightly closed.

The inner valve member 24 is positioned within the fluid passageway 18 such that a portion of the inner valve member 24 lies within the through passage 38 of the outer valve member 22 . Also, the inner valve member 24 is displaceable in the direction of the longitudinal axis L with respect to the plug body 20 . An annular resilient sealing member 40 is mounted on the outer peripheral surface 24a of the inner valve member 24 for sealing engagement with the inner peripheral surface 22b of the outer valve member 22. As shown in FIG. In this embodiment, the resilient sealing member 40 is a rubber O-ring.

The coil spring 26 includes a large-diameter portion 42, a small-diameter portion 44 located behind the large-diameter portion 42, and a connecting portion 46 that radially connects a rear end 42a of the large-diameter portion 42 and a front end 44a of the small-diameter portion 44. Consists of A large diameter portion 42 is arranged around the outer valve member 22 and a small diameter portion 44 having a smaller diameter than the large diameter portion 42 is arranged around the inner valve member 24 . This constrains the radial position of the outer valve member 22 and the inner valve member 24 relative to the plug body 20 . Coil spring 26 is fixed in position with respect to plug body 20 by engaging coupling portion 46 with engaging stepped portion 48 formed on inner peripheral surface 20 a of plug body 20 . A first spring portion 42 formed by an enlarged diameter portion 42 extends between a rearward end 42a and a forward end 42b which engages the outer valve member 22 to propel the outer valve member 22 forwardly relative to the plug body 20. energized. A rear end 42a of the first spring portion 42 is connected to a connecting portion 46 that is locked by a locking step portion 48 to form a stationary end 42a that is stationary with respect to the plug body 20. As shown in FIG. On the other hand, the front end 42 b of the first spring portion 42 constitutes a displacement end 42 b that is displaced together with the outer valve member 22 . A second spring portion 44, also formed by a reduced diameter portion 44, extends between a forward end 44a and a rearward end 44b which engages the inner valve member 24 to bias the inner valve member 24 rearwardly relative to the plug body 20. is biased toward A front end 44a of the second spring portion 44 is connected to a connecting portion 46 locked to a locking step portion 48 to form a stationary end 44a stationary with respect to the plug body 20. As shown in FIG. 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. As shown in FIG. In the disconnected state of FIG. 1, the outer valve member 22 is biased forward by the first spring portion 42 to the closed position, and the inner valve member 24 is biased rearward by the second spring portion 44 to form the elastic sealing member. 40 in sealing engagement with the outer valve member 22 to close 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 biased by the coil springs 26, respectively. Since the outer valve member 22 and the inner valve member 24 are urged in opposite directions by the coil spring 26, there may be dimensional errors in each member during manufacturing, or the elastic sealing member 40 may be used repeatedly. , the sealing engagement between the first inner metal seal surface 32 and the first outer 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 is suitably accomplished. Since the biasing force of the second spring portion 44 is set to be weaker than the biasing force of the first spring portion 42 , the outer valve member 22 is biased against the first spring portion 42 only by the biasing force of the second spring portion 44 . There is no rearward displacement from the closed position against forces.

On the inner peripheral surface 20a of the plug body 20, a retainer projection 49 is formed that protrudes radially inward at a position between the stationary end 44a and the displaced end 44b of the second spring portion 44 in the direction of the longitudinal axis L. ing. A displacement end 44 b of the second spring portion 44 has a larger diameter than other portions of the second spring portion 44 and has an outer diameter larger than the inner diameter of the retainer projection 49 . The inner valve member 24 is urged rearwardly by the second spring portion 44 as described above, but when the fluid pressure in the fluid passage 18 increases, for example, the second spring portion 44 is pushed against the inner valve member 24 . 1, the inner valve member 24 will be displaced forwardly from the position of FIG. In this case, the displacement end 44b of the second spring portion 44 engages with the retaining projection 49 to prevent further forward displacement of the inner valve member 24, resulting in excessive displacement of the inner valve member 24. 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 stepped portion 48 by the biasing force of the first spring portion 42, and the first spring Section 42 is not compressed.

Further, on the inner peripheral surface 20 a of the plug body 20 , a locking projection 50 projecting radially inward is formed behind the retaining projection 49 . A locking projection 52 projecting radially outward is formed on the outer peripheral surface 24 a of the inner valve member 24 . As will be described later, when the outer valve member 22 is pushed rearward, the inner valve member 24 is displaced rearward together with the outer valve member 22 by the biasing force of the second spring portion 44 . The rearward displacement of the inner valve member 24 is restricted by the engagement of the locking projection 52 with the locking projection 50 of the plug body 20, and further rearward displacement of the inner valve member 24 is prevented. It's becoming

The socket 12 includes a tubular socket body (mating fitting body) 60 defining a fluid passageway 58 extending from the forward end opening 54 to the rearward end opening 56 and displaceably disposed within the fluid passageway 58 in the direction of the longitudinal axis L. and a valve member 62 . The socket body 60 is composed of a front member 64 and a rear member 66 which are screwed together. On the outer peripheral surface 66a of the rear member 66 is a second outer peripheral metal seal surface whose diameter is reduced forward (to the right in the drawing). 67 is formed, and a third inner peripheral metal seal surface 68 whose diameter is reduced forward is formed on the inner peripheral surface 66b. A third outer peripheral metal seal surface 70 is formed on the outer peripheral surface 62a of the valve member 62, the diameter of which decreases toward the front. The valve member 62 is in the closed position (see FIG. 1) where the third outer metal seal surface 70 presses and engages the third inner metal seal surface 68 by the biasing force of the valve spring 72 to form a fluid-tight seal and close the fluid passage 58 (see FIG. 1). ) and an open position (FIGS. 5 to 7) in which the fluid passage 58 is opened by displacing it rearward (to the left in the drawing) from the closed position to release the pressure engagement and open the fluid passage 58. . The valve member 62 is biased forward toward the closed position by a valve spring 72 .

A front member 64 of the socket body 60 is provided with a plurality of locking element holding holes 74 penetrating in the radial direction, and a spherical locking element 76 is arranged in each of the locking element holding holes 74 . A sleeve 78 is arranged on the outer peripheral surface 60 a of the socket body 60 . a connecting position (FIGS. 1, 6 and 7) in which the sleeve 78 holds the lock 76 in a locking position where a portion of the lock 76 protrudes radially inward from the inner peripheral surface 64a of the front member 64 of the socket body 60; It is displaceable in the direction of the longitudinal axis L between the disengaged position (FIGS. 2 to 5) where it is displaced rearward from the connected position to allow the locking element 76 to be displaced radially outward. A spring holding member 82 is further mounted on the outer peripheral surface 60 a of the socket body 60 to hold the sleeve spring 80 in a compressed state between itself and the sleeve 78 . Sleeve 78 is biased forward toward the coupled position by a sleeve spring 80 .

When connecting the plug 10 and the socket 12, the sleeve 78 is displaced rearward from the disconnected state of FIG. Then, as shown in FIG. 2, the lock piece 76 is pushed radially outward by the plug body 20 to reach the unlocked position. The insertion portion 86 formed with the valve pressing portion 84 of the socket body 60 is inserted into the inside of the plug body 20, and the elastic sliding member 88 made of a rubber O-ring attached to the insertion portion 86 slides into the plug body. 20 abuts on the second inner peripheral metal seal surface 34 . When the plug 10 is further inserted into the socket 12, the elastic sliding member 88 slides on the second inner metal seal surface 34 while being crushed by the second inner metal seal surface 34, as shown in FIG. To go. Also, the valve pressing portion 84 of the socket 12 contacts the outer valve member 22 of the plug 10 and the valve member 62 of the socket 12 contacts the inner valve member 24 of the plug 10 . 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, thereby The metal seal between the peripheral metal seal surface 32 and the first peripheral metal seal surface 36 is released. At this time, the inner valve member 24 biased 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 until the locking projection 52 comes into contact with the locking projection 50 of the plug body 20, after which only the outer valve member 22 is displaced rearward. This releases the sealing engagement between the inner valve member 24 and the outer valve member 22 via the resilient sealing member 40 . Also, 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 drawing), and the third inner peripheral metal seal surface 68 and the third outer peripheral metal seal surface 70 are displaced. The metal seal between is also released. In the state shown in FIG. 4, the metal seal on the first inner metal seal surface 32 is released, but the contact between the first inner metal seal surface 32 and the second inner metal seal surface 34 of the plug body 20 is prevented. The elastic sliding member 88 is in sealing engagement with the intermediate inner peripheral surface 90 between them, and the state in which the fluid passage 18 of the plug 10 is fluid-sealed from the outside is maintained. Also, the inner valve member 24 of the plug 10 is inserted inside the socket body 60 and the resilient sealing member 40 attached to the inner valve member 24 is in sealing engagement with the inner peripheral surface 66b of the rear member 66 of the socket body 60. , the fluid passageway 18 of the plug 10 and the fluid passageway 58 of the socket 12 are not yet in communication. When the plug 10 is further inserted into the socket 12, as shown in FIG. 5, the outer valve member 22 further compresses the first spring portion 42 of the coil spring 26 and displaces rearward to the open position. While sliding on the intermediate inner peripheral surface 90 , the elastic sliding member 88 crosses the intermediate inner peripheral surface 90 to reach the first inner peripheral metal seal surface 32 , and further slides on the first inner peripheral metal seal surface 32 . move. Also, the second inner peripheral metal seal surface 34 of the plug body 20 contacts the second outer peripheral metal seal surface 67 of the socket body 60 . Inner valve member 24 is further inserted into socket body 60 to force valve member 62 of socket 12 further rearwardly to displace 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. 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 biasing force of the sleeve spring 80 as shown in FIG. The lock piece pressing surface 94 presses the lock piece 76 radially inward. The lock piece 76 pushed radially inward is partially pushed into the lock piece engaging groove 96 formed in the outer peripheral surface 20 b of the plug body 20 . The sleeve 78 is urged forward by the sleeve spring 80 even in the connected position, and the lock piece 76 receives a radially inward force from the inclined lock piece pressing surface 94 . A front side surface 96a of the lock piece engaging groove 96 is inclined so as to increase in diameter toward the front, and the lock piece 76 is pressed against this front side surface 96a. Therefore, the plug body 20 receives a force in the direction (leftward in the figure) in which it is pulled into the socket body 60 by the locking element 76 that is pressed radially inward. As a result, the second inner metal seal surface 34 of the plug 10 is press-engaged with the second outer metal seal surface 67 of the socket 12 to form a metal seal with the second outer metal seal surface 67, thereby A fluid tight seal is provided between the body 20 and the socket body 60 . In this way, the pipe joint 1 becomes connected.

In the connected state of FIG. 6, both the elastic sliding member 88 and the elastic sealing member 40 made of rubber material are positioned within the fluid passages 18 and 58, and the fluid flowing through the fluid passages 18 and 58 is prevented from moving. exposed. An example of the fluid flowing through the fluid passages 18, 58 is a high-temperature organic heat transfer medium, which may oxidize and solidify upon contact with air. In the pipe joint 1, the elastic sliding member 88 and the elastic sealing member 40 are positioned within the fluid passages 18, 58 and are not exposed to air in the connected state. and the elastic sealing member 40 can be prevented 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 to be displaced to the disconnection position. However, when an excessive force acts between the plug 10 and the socket 12 in the direction of separating them from each other, the lock piece 76 is displaced radially outward due to the force received from the front side surface 96a of the lock piece engaging groove 96. At the same time, the sleeve 78 may be displaced rearward and the connection between the plug 10 and the socket 12 may be released. Moreover, 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 behind is arranged in the direction of the longitudinal axis L. position is adjustable. Specifically, the spring holding member 82 is screwed to the socket body 60, and can be displaced in the direction of the longitudinal axis L by rotating the spring holding member 82 around the longitudinal axis L. It's 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 lock 76 is pushed radially inward through the sleeve 78 with a greater force. It will be done. As a result, the plug body 20 is pulled in with a greater force, the pressing force between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 increases, and the metal seal becomes stronger. In addition, a situation in which the connection between the plug 10 and the socket 12 is released due to a force in the direction of separating the plug 10 and the socket 12 caused by the pressure of the internal fluid or the like is less likely to occur. Furthermore, by setting the spring holding member 82 to the sleeve fixing position where the front end abutment portion 82a abuts on the stepped receiving portion 78a of the sleeve 78, the sleeve 78 is prevented from being displaced rearward toward the disconnection position. This makes it possible to more reliably prevent unexpected disconnection. The spring holding member 82 may be made slidable in the direction of the longitudinal axis L without being screwed into the socket body 60 at the position shown in FIG. 6, and may be screwed only near the position shown in FIG. By doing so, it becomes possible to quickly perform the operation of setting the spring holding member 82 to the position shown in FIG.

When disconnecting the plug 10 and the socket 12 , the sleeve 78 is displaced to the disconnecting 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 connecting the plug 10 and the socket 12 , the outer valve member 22 of the plug 10 is pushed by the valve pressing portion 84 of the socket 12 , thereby displacing the outer valve member 22 from the closed position to the open position. and the inner valve member 24 to release the closure of the fluid passage 18 . In the pipe joint 1, only the first spring portion 42 biasing the outer valve member 22 is compressed at this time, and the second spring portion 44 biasing the inner valve member 24 is not compressed. Therefore, it is possible to reduce the load required when inserting the plug 10 into the socket 12 as compared with the conventional one.

Also, when the plug 10 and the socket 12 are attached and detached, the elastic sliding member 88 attached to the socket body 60 slides over the first inner peripheral metal seal surface 32 and the second inner peripheral metal seal surface 34 of the plug body 20 . It is designed to slide upward. As a result, foreign matter such as dust and dirt attached to the first inner peripheral metal seal surface 32 and the second inner peripheral metal seal surface 34 can be removed. Similarly, the elastic sealing member 40 attached to the inner valve member 24 of the plug 10 slides on the third inner peripheral metal seal surface 68 of the socket body 60, thereby causing the third inner peripheral metal seal surface 68 to slide. Foreign matter such as attached dust and dirt can be removed. Since metal seals are sealed by directly contacting relatively hard members, even the slightest amount of foreign matter adhering to the seal surface can have a large effect on the sealing performance, making proper sealing impossible. 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, and 68 at the time of attachment and detachment, as described above, the metal seal may not be properly sealed due to foreign matter. It is possible to prevent it from becoming impossible.

As shown in FIG. 8, the second inner metal seal surface 34 of the plug body 20 and the second outer metal seal surface 67 of the socket body 60 are both inclined with respect to the longitudinal axis L by an inclination angle θ. The plug body 20 and the socket body 60 are made of materials with different thermal expansion coefficients, and in this embodiment, the plug body 20 is made of SUS310 (thermal expansion coefficient: 14.4×10 ⁻⁶ ). The socket body 60 is made of SUS304 (thermal expansion coefficient: 16.7×10 ⁻⁶ ). Since the coefficient of thermal expansion of the plug body 20 located outside is smaller than that of the socket body 60 located inside, the plug body 20 and the socket body 60 are separated from each other by a high-temperature fluid flowing through the pipe joint 1 or the like. When heated, the inner socket body 60 will expand more. Due to the difference in the amount of expansion due to heating, the pressing force between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 increases with thermal expansion.

Here, assuming that the force in the radial direction acting between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 is W, the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface The force F in the direction along 67 and the force N in the direction perpendicular to it are respectively as follows.
F = W sin θ
N=W cos θ
Further, when the coefficient of static friction between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 is μ, the friction between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 is The maximum static friction force F _max is:
F _max = μN
= μW cos θ
From these, the conditions for preventing slippage between the second inner peripheral metal seal surface 34 and the second outer peripheral metal seal surface 67 due to the force W in the radial direction caused by thermal expansion are obtained as follows.
_F≤Fmax
W sin θ≦μW cos θ
tan θ≦μ

In the pipe joint 1, the coefficient of static friction μ and the angle of inclination θ are set so as to satisfy the relationship tan θ≦μ. Specifically, the inclination angle .theta. .2. Therefore, even if the pressing force between the second inner metal seal surface 34 and the second outer metal seal surface 67 increases due to thermal expansion, the second inner metal seal surface 34 and the second outer metal seal surface 67 are held together by friction and no slippage occurs. 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. 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 material forming the plug body 20 and the socket body 60 can be appropriately changed according to the usage environment. The amount of thermal contraction of the plug body 20 is greater than that of the socket body 60 by selecting a material whose coefficient of thermal expansion is greater than that of the inner socket body 60, The pressing force between the second inner metal seal surface 34 and the second outer metal seal surface 67 may be increased when the plug body 20 and the socket body 60 are cooled. Also, the relationship between the first inner peripheral metal seal surface 32 and the first outer peripheral metal seal surface 36 and the relationship between the third inner peripheral metal seal surface 68 and the third outer peripheral metal seal surface 70 satisfy the above conditions. can be set as

In a 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. A resilient sealing member 199 is provided. 7, the elastic sealing member 199 is in sealing engagement with the second outer peripheral metal seal surface 167, and the second inner peripheral metal seal surface 134 is still in contact with the second outer peripheral metal seal surface 134. It does not engage with the metal seal surface 167 . When the pipe joint 101 is heated by, for example, flowing a high-temperature fluid, the gap between the second inner peripheral metal seal surface 134 and the second outer peripheral metal seal surface 167 gradually narrows due to the above-described 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 to form a metal seal. Alternatively, by displacing the spring holding member 82 to the sleeve fixing position as shown in FIG. The perimeter metal seal surface 134 and the second perimeter metal seal surface 167 may also engage 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, the coil spring that biases the outer valve member and the inner valve member of the plug does not necessarily have to be constructed as a single member, and the first spring portion that biases the outer valve member and the inner valve member are biased. The second spring portion may be configured as a separate coil spring, and the stationary end of each spring portion may be engaged with the plug body. Also, the structure consisting of the outer valve member, the inner valve member and the coil spring can be provided on the side of the socket. The sealing engagement between the inner peripheral surface of the plug body and the outer peripheral surface of the outer valve member may be through an elastic member such as an O-ring instead of the metal seal. Alternatively, the sealing engagement between the outer valve member and the inner valve member may be a metal seal. In addition, the term "metal seal" used in the specification of the present application is not necessarily limited to contact between metals, but contact between relatively hard non-metallic materials such as polyetheretherketone (PEEK). Sealing provided by contact between such non-metallic materials and metallic materials shall also be included. Therefore, the "metal seal surface" in the present application does not necessarily have to be a metal surface.

1 pipe joint 10 plug (pipe joint member)
12 socket (corresponding pipe joint member)
14 front end opening 16 rear end opening 18 fluid passage 20 plug body (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 24a outer peripheral surface 26 coil spring 28 front member 28a end surface 30 rear member 30a end surface 32 first inner peripheral metal seal surface 34 second inner Peripheral metal seal surface 36 First perimeter metal seal surface (seal engagement portion)
38 Through passage 40 Elastic sealing member 42 Large diameter portion, first spring portion 42 a Rear end, stationary end 42 b Front end, displacement end 44 Small diameter portion, second spring portion 44 a Front end, stationary end 44 b Rear end, displacement end 46 Connecting portion 48 Locking stepped portion 49 Retaining projection 50 Locking projection 52 Locking projection 54 Front end opening 56 Rear end opening 58 Fluid passage 60 Socket main body (corresponding pipe joint main 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 Locking piece holding hole 76 Locking piece 78 Sleeve 78a Receiving portion 80 Sleeve spring 82 Spring holding member 82a Front end contact portion 84 Valve pressing portion 86 Insertion portion 88 Elastic sliding member 90 Intermediate inner peripheral surface 94 Locking piece pressing surface 96 Locking Secondary locking groove 96a Front side surface 101 Pipe joint 134 Second inner peripheral metal seal surface 167 Second outer peripheral metal seal surface 198 Annular groove 199 Elastic sealing member L Longitudinal axis

Claims (6)

A pipe joint member detachably connected to a corresponding pipe joint member,
a tubular fitting body having a front end opening, a rear end opening, and a fluid passageway extending from the front end opening to the rear end opening;
an outer peripheral surface disposed within the fluid passageway and provided with a sealing engagement portion for sealing engagement with the inner peripheral surface of the fitting body; a cylindrical outer valve member having a peripheral surface, wherein the sealing engagement portion sealingly engages the inner peripheral surface of the pipe fitting body to provide a gap between the outer peripheral surface and the inner peripheral surface of the pipe fitting body; an outer valve member displaceable in the direction of the longitudinal axis between a closed position that closes the valve member and an open position that displaces rearwardly from the closed position to disengage the sealing engagement;
an inner valve member disposed within the fluid passageway and at least partially within the through passage of the outer valve member and displaceable in the direction of the longitudinal axis;
extending between a stationary end stationary relative to the fitting body and a displaceable end engaging and displacing with the outer valve member to move the outer valve member forward relative to the fitting body; a first spring portion biasing the outer valve member into the closed position;
extending between a stationary end stationary relative to the fitting body and a displacement end engaging and displacing with the inner valve member to move the inner valve member rearwardly relative to the fitting body. a biasing second spring portion;
with
the second spring portion has a weaker biasing force than the first spring portion;
wherein, when the outer valve member is in the closed position, the inner valve member sealingly engages the outer valve member by the biasing force of the second spring portion to close the through passage. Element. A large-diameter portion forming the first spring portion, a small-diameter portion located behind the large-diameter portion and forming the second spring portion and having a smaller diameter than the large-diameter portion, and a rear end of the large-diameter portion. and a stationary end of the second spring portion, which is the front end of the small diameter portion, in a radial direction, the connecting portion being the pipe joint 2. The fitting member of claim 1, comprising a coil spring locked to the body. The large diameter portion of the coil spring is positioned around the outer valve member, the small diameter portion is positioned around the inner valve member, and the coil spring forces the outer valve member and the inner valve against the fitting body. 3. A pipe fitting member according to claim 2, adapted to retain the radial position of the member. The inner peripheral surface of the pipe joint body has a retainer projection protruding radially inward at a position between the stationary end and the displaceable end of the second spring portion in the direction of the longitudinal axis, the displacement end of the second spring portion has an outer diameter larger than the inner diameter of the retainer projection;
When the inner valve member is displaced forward, the displacing end of the second spring portion is engaged with the retainer projection to prevent further forward displacement of the inner valve member. 4. The pipe joint member according to any one of claims 1 to 3. The inner peripheral surface of the pipe joint body protrudes radially inward so that when the inner valve member is displaced rearward, the inner valve member engages to prevent further rearward displacement of the inner valve member. The outer valve member has a locking projection, and the outer valve member is displaced rearward relative to the inner valve member engaged with the locking projection to release the closure of the through passage by the inner valve member. 5. The pipe joint member according to any one of claims 1 to 4, wherein the pipe joint member is configured as A pipe joint comprising the pipe joint member according to any one of claims 1 to 5 and a corresponding pipe joint member detachably connected to the pipe joint member,
The corresponding pipe joint member includes a valve pressing portion that is inserted into the fluid passage of the pipe joint member when the pipe joint member and the corresponding pipe joint member are connected, and the valve pressing portion A pipe fitting adapted to push the valve member to compress the first spring portion while displacing the outer valve member to the open position.

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