Patent Publication Number: US-2022221076-A1

Title: Safety joint

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to JP2021-003869 filed on Jan. 14, 2021, the disclosure of which is incorporated herein by reference. 
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
     Not Applicable 
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a filling apparatus for filling gas such as hydrogen gas used as fuel. More particularly, the present invention relates to a pipe joint for safely separating the filling apparatus and a gas filling nozzle from each other in an emergency while a gas is filled with the filling apparatus. 
     2. Description of the Related Art 
     For example, as show in  FIG. 14 , to a vehicle A using hydrogen as fuel, at a hydrogen filling station is filled hydrogen gas after a filling nozzle  202  attached to an end of a filling hose  201  of a hydrogen filling apparatus  200  is connected to a vehicle side filling port  203 . Then, this filling of hydrogen gas is performed while being controlled depending on the pressure of a hydrogen tank  204  mounted to the vehicle A. Here, when the vehicle A runs to pull the filling hose  201  while hydrogen gas is filled, for instance, parts such as the filling nozzle  202  and the filling hose  201  are broken to inject a hydrogen gas, so that it becomes a dangerous condition. Then, a pipe joint  300  for emergency releasing is mounted between the hydrogen filling apparatus  200  and the filling hose  201 , and when to the filling hose  201  is applied a tensile force equal to or higher than a predetermined value, the pipe joint  300  for emergency releasing is divided to prevent the parts such as the filling nozzle  202  and the filling hose  201  from being broken. 
     As a prior art, the present applicant proposed a pipe joint for emergency releasing including: a cylindrical plug (filling nozzle side member) in which a flow path is formed; a cylindrical socket (filling apparatus side member) in which a flow path is formed; and when the plug is inserted into the socket, shutoff valves open the flow paths of the plug and the socket to communicate the flow paths with each other, and when the plug is detached from the socket, the shutoff valves close. In the pipe joint for emergency releasing, central axes of the flow paths of the plug and the socket do not form the same straight line; when the plug is inserted into the socket, an end of a socket side valve stem (an end, opposing the end of the socket side valve stem, of a valve element) contacts with a plug side rod accommodating case and a valve element mounted to the other side of the socket side valve stem is held at a position separated from a socket side valve seat against an elastic repulsive force of an elastic body on the socket side, and a locking member held in the plug side rod accommodating case is restricted to move radially outward by an inner wall at a socket body side opening, and a plug side valve stem contacts with the locking member and does not move toward the socket side, and a valve body provided on the plug side valve stem is held at a position separated from a plug side valve seat against an elastic repulsive force of an elastic body on the plug side (refer to Patent Document 1). This pipe joint (disclosed in the Patent Document 1) is useful. 
     However, in the pipe joint  100  of the prior art (described in the Patent Document 1), when a large tensile force acts on the filling hose  201  (shown in  FIG. 14 ), at an initial stage of the process that the plug  10  is pulled out from the socket  22  (the stage at which the plug  10  starts to come out), as shown in  FIG. 15 , the socket side rod  22  connected to the valve body  25  on the socket  20  side is placed on the plug side valve stem  2  or a cover member  3  of the valve stem. Under the condition (the state shown in  FIG. 15 ), the socket side valve body  25  positions separately from the socket side valve seat  21 E against the elastic repulsive force of a spring  23  on the socket  20  side, which causes the socket side shutoff valve  24  to be held in an open state. For that reason, at the initial stage where the plug  10  is ejected from the socket  20  (the stage where the plug  10  is beginning to be ejected), a high-pressure hydrogen gas supplied from the filling apparatus  200  ( FIG. 14 ) through the opening portion  21 C on the socket  20  side flows out to the outside of the pipe joint  100  as a so-called “outgas”. In  FIG. 15 , the outflow of the outgas is indicated by the arrow OG. 
     Prior Art document Japan Patent No. 6540967 gazette 
     BRIEF SUMMARY 
     The present invention has been made in consideration of the above problems in the prior art, and the object thereof is to provide a safety joint that can immediately shut off a hydrogen gas flow path at the initial stage when a plug, which is a nozzle side member, comes out of a socket, which is a filling apparatus side member, to prevent release of outgas. 
     A safety joint ( 100 ,  100 - 1 ,  100 - 2 ) of the present invention includes: a cylindrical nozzle side member ( 10 : plug) with a flow path ( 1 A: in-plug flow path) formed inside, a shutoff valve ( 5 : plug side shutoff valve) of the nozzle side member ( 10 ) opens when the nozzle side member ( 10 ) is connected to a filling apparatus side member ( 20 : socket); and the filling apparatus side member ( 20 ) with a cylindrical shape, a flow path ( 21 A: socket side flow path) in communication with the flow path ( 1 A: in-plug flow path) of the nozzle side member ( 10 ) is formed in the filling apparatus side member ( 20 ) and a shutoff valve ( 24 : socket side shutoff valve) of the filling apparatus side member ( 20 ) opens when the filling apparatus side member ( 20 ) is connected to the nozzle side member ( 10 ); and when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ), the shutoff valves ( 5 ,  24 ) of the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) close, the safety joint ( 100 ,  100 - 1 ,  100 - 2 ) (for emergency release) is characterized in that a mechanism for closing the shutoff valve ( 24 : socket side shutoff valve) of the filling apparatus side member ( 20 ) includes: an elastic member ( 23 : socket side spring), of the filling apparatus side member ( 20 ), for urging a filling apparatus side valve body ( 25 : socket side valve body); a rod-shaped member ( 22 : rod) connected to the filling apparatus side valve body ( 25 ); and a support member ( 26 ,  27 ,  28 : rod support member) for supporting the rod-shaped member ( 22 ), wherein the support member ( 26 ,  27 ,  28 ) moves together with the nozzle side member ( 10 ) to a state where the support member ( 26 ,  27 ,  28 ) does not support (mount) the rod-shaped member ( 22 ) when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ). 
     In the present invention, it is preferable that the support member ( 26 ) includes a disk-like member ( 26 D) with a protrusion ( 26 A) and a notch ( 26 B), the disk-like member ( 26 D) rotatably supported; an opening ( 3 : groove) into which the protrusion ( 26 A) of the disk-like member ( 26 D) is inserted is formed on a protruding portion ( 3 ) of the nozzle side member ( 10 ); the notch ( 26 B) of the disk-like member ( 26 D) has a flat portion ( 26 C); an end of the rod-shaped member ( 22 ) contacts with the flat portion ( 26 C) and is supported (mounted) thereon when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected with each other. 
     Further, in the present invention, it is preferable that the support member ( 27 ) includes a rod mounting member ( 27 D) with a protrusion ( 27 A), a flat portion ( 27 B) and an inclined portion ( 27 C: tapered portion); and a deformation member ( 27 F) with an inclined portion ( 27 E) having a shape complementary to the inclined portion ( 27 C) of the rod mounting member ( 27 D) and attached to the filling apparatus side member ( 20 ), wherein an opening ( 3 D: groove) into which the protrusion ( 27 A) of the rod mounting member ( 27 D) is inserted is formed on the protruding portion ( 3 ) of the nozzle side member ( 10 ); when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected with each other, an end portion of the rod-shaped member ( 22 ) contacts with the flat portion ( 27 B) of the rod mounting member ( 27 D) and is supported (mounted) thereon; an opening ( 21 C: through hole) into which the protruding portion ( 3 ) of the nozzle side member ( 10 ) is inserted extends in the filling apparatus side member ( 20 ) in a direction orthogonal to the flow path ( 21 A: in-socket flow path) of the filling apparatus side member ( 20 ), and a large diameter portion ( 21 H) is formed in a region on the nozzle side of the flow path ( 21 A) of the filling apparatus side member ( 20 ) in the opening ( 21 C); and the protrusion ( 27 A) is configured to come off from the opening ( 3 D) when the inclined portion ( 27 C) of the rod mounting member ( 27 D) comes into contact with the inclined portion ( 27 E) of the deformation member ( 27 F). 
     Still further, in the present invention, it is preferable that the support member ( 28 ) has an annular portion ( 28 A) and a ball holding portion ( 28 B) that hold the ball ( 29 ) in between; when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected with each other, an end portion of the rod-shaped member ( 22 ) contacts with the annular portion ( 28 A) and is supported (mounted) thereon; a recess ( 3 E: groove) in which a part of the ball ( 29 ) is held by the ball holding portion ( 28 B) is inserted is formed in the protruding portion ( 3 ) of the nozzle side member ( 10 ); in the filling apparatus side member ( 20 ), an opening ( 21 C: through hole) into which the protruding portion ( 3 ) of the nozzle side member ( 10 ) is inserted extends in the filling apparatus side member ( 20 ) in a direction orthogonal to the flow path ( 21 A) of the filling apparatus side member ( 20 ), and a large diameter portion ( 21 I) is formed in a region on the nozzle side of the flow path ( 21 A) of the filling apparatus side member ( 20 ) in the opening ( 21 C); and when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ) and the ball ( 29 ) reaches the large diameter portion ( 21 I), the ball ( 29 ) disengages from a recess ( 3 E) and moves into the large diameter portion ( 21 I). 
     According to the safety joint ( 100 ,  100 - 1 ,  100 - 2 ) of the present invention with the above-mentioned configuration, the support member ( 26 ,  27 ,  28 : rod support member) supporting (mounting) the rod-shaped member ( 22 : rod) connected to the valve body ( 25 ) on the filling apparatus side, in conjunction with the nozzle side member ( 10 ), when the nozzle side member ( 10 ) is disengaged from the filling apparatus side member ( 20 ), at the initial stage, moves to a state in which the support member ( 26 ,  27 ,  28 : rod support member) does not support (place) the rod-shaped member ( 22 ). When the rod-shaped member ( 22 ) is no longer supported by the support member ( 26 ,  27 ,  28 ), the rod-shaped member ( 22 ) is in a state of not blocking the movement of the valve body ( 25 ), and thereby the elastic member ( 23 ) on the filling apparatus side presses the valve body ( 25 ) on the filling apparatus side and the valve body ( 25 ) sits on the valve seat ( 21 E: socket side valve seat). With this, at the initial stage when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ), the shutoff valve ( 24 ) on the filling apparatus side shuts off, and the generation of outgas is suppressed. 
     For example, when the support member ( 26 ) includes a disk-like member ( 26 D) with a protrusion ( 26 A) and a notch ( 26 B), the disk-like member ( 26 D) rotatably supported; an opening ( 3 : groove) into which the protrusion ( 26 A) of the disk-like member ( 26 D) is inserted is formed on a protruding portion ( 3 ) of the nozzle side member ( 10 ); an end of the rod-shaped member ( 22 ) contacts with the flat portion ( 26 C) and is supported (mounted) thereon when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected with each other, the movement of the nozzle side member ( 10 ) to disengage from the filling apparatus side member ( 20 ) is converted into the rotation of the disk-shaped member ( 26 D) via the opening ( 3 C) of the nozzle side member ( 10 ) and the protrusion ( 26 A) of the disc-shaped member ( 26 D), when the disk-shaped member ( 26 D) rotates, the rod-shaped member ( 22 ) is not supported (mounted) on the flat portion ( 26 C) of the disk-shaped member ( 26 D). 
     In addition, when the support member ( 27 ) has a rod mounting member ( 27 D) with a protrusion ( 27 A), a flat portion ( 27 B) and an inclined portion ( 27 C: tapered portion), and an opening ( 3 D: groove) into which a protrusion ( 27 A) of the rod mounting member ( 27 D) is inserted is formed in the protruding portion ( 3 ) of the nozzle side member ( 10 ), and when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected, an end of the rod-shaped member ( 22 ) is in contact with the flat portion ( 27 B) of the rod mounting member ( 27 D) and is supported (mounted) thereon, the movement of the nozzle side member ( 10 ) away from the filling apparatus side member ( 20 ) is converted into the movement of the rod mounting member ( 27 D) via the opening ( 3 D) of the nozzle side member ( 10 ) and the protrusion ( 27 A) of the rod mounting member ( 27 D), and when the rod mounting member ( 27 D) moves, the end portion of the rod-shaped member ( 22 ) is not supported (mounted) on the flat portion ( 27 B) of the rod mounting member ( 27 D). Further, a deformation member ( 27 F) with an inclined portion ( 27 E) having a shape complementary to the inclined portion ( 27 C) of the rod mounting member ( 27 D) and attached to the filling apparatus side member ( 20 ) is mounted, and when the inclined portion ( 27 C) of the rod mounting member ( 27 D) comes into contact with the inclined portion ( 27 E) of the deforming member ( 27 F), the protrusion ( 27 A) is configured to come off from the opening ( 3 D), thereby when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ), the inclined portion ( 27 C) of the rod mounting member ( 27 D) comes into contact with the inclined portion ( 27 E) of the deformation member ( 27 F), the rod mounting member ( 27 D) rides on the inclined portion ( 27 E) of the deformation member ( 27 F), and the rod mounting member ( 27 D) rotates around an edge of the opening ( 3 D) of the nozzle side member ( 10 ) and is accommodated in the large diameter portion ( 21 H). As a result, the nozzle side member ( 10 ) is smoothly disengaged from the filling machine side member ( 20 ) without the rod mounting member ( 27 D) being in a so-called “bitten” state with other members. 
     Still further, in the present invention, when the support member ( 28 ) has an annular portion ( 28 A) and a ball holding portion ( 28 B) that hold the ball ( 29 ) in between; when the nozzle side member ( 10 ) and the filling apparatus side member ( 20 ) are connected with each other, an end portion of the rod-shaped member ( 22 ) contacts with the annular portion ( 28 A) and is supported (mounted) thereon; and a recess ( 3 E: groove) in which a part of the ball ( 29 ) held by the ball holding portion ( 28 B) is inserted is formed in the protruding portion ( 3 ) of the nozzle side member ( 10 ); in the filling apparatus side member ( 20 ), an opening ( 21 C: through hole) into which the protruding portion ( 3 ) of the nozzle side member ( 10 ) is inserted extends in the filling apparatus side member ( 20 ) in a direction orthogonal to the flow path ( 21 A: in-socket flow path) of the filling apparatus side member ( 20 ), and a large diameter portion ( 211 ) is formed in a region on the nozzle side of the flow path ( 21 A) of the filling apparatus side member ( 20 ) in the opening ( 21 C), the movement that the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ) is converted into the movement of the ball holding portion ( 28 B) via the recess ( 3 E: groove) and the ball ( 29 ) of the nozzle side member ( 10 ), when the ball holding portion ( 28 B) moves, the end portion of the rod-shaped member ( 22 ) is not supported (mounted) on the annular portion ( 28 A). Then, when the nozzle side member ( 10 ) is disconnected from the filling apparatus side member ( 20 ) and the ball ( 29 ) reaches the large diameter portion ( 21 I), the ball ( 29 ) is disconnected from the recess ( 3 E) and moves into the large diameter portion ( 211 ), so that the ball holding portion ( 28 B) and the protruding portion ( 3 ) of the nozzle side member ( 10 ) are separated, thereby the ball holding portion ( 28 B) and the ball ( 29 ) do not hinder the movement that the nozzle side member ( 10 ) is separated from the filling apparatus side member ( 20 ). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an explanatory cross-sectional view of a safety joint according to the first embodiment of the present invention in a state where a plug is connected to a socket. 
         FIG. 2  is an explanatory enlarged view of a support member in the safety joint shown in  FIG. 1 . 
         FIG. 3  is an explanatory cross-sectional view of a state in which the plug is disconnected from the socket in the safety joint shown in  FIG. 1 . 
         FIG. 4  is an explanatory cross-sectional view of a safety joint according to the second embodiment of the present invention in a state where a plug is connected to a socket. 
         FIG. 5  is an explanatory enlarged view of a support member in the safety joint shown in  FIG. 4 . 
         FIG. 6  is an explanatory cross-sectional view showing an initial state in which the plug is disconnected from the socket in the safety joint shown in  FIG. 4 . 
         FIG. 7  is an explanatory cross-sectional view of a state in which the plug is disconnected from the socket in the safety joint shown in  FIG. 4 . 
         FIG. 8  is an explanatory cross-sectional view of a safety joint according to the third embodiment of the present invention in a state where a plug is connected to a socket. 
         FIG. 9  is an explanatory enlarged view of a support member in the safety joint shown in  FIG. 8 . 
         FIG. 10  is an explanatory cross-sectional view showing an initial state in which the plug is disconnected from the socket in the safety joint shown in  FIG. 8 . 
         FIG. 11  is an explanatory cross-sectional view showing the state just before the plug is disconnected from the socket in the safety joint shown in  FIG. 8 . 
         FIG. 12  is an explanatory cross-sectional view of a state in which the plug is disconnected from the socket in the safety joint shown in  FIG. 8 . 
         FIG. 13  is a cross-sectional view showing a safety joint according to a modification example of the embodiment. 
         FIG. 14  is an explanatory view showing an outline of a hydrogen filling facility. 
         FIG. 15  is a cross-sectional view showing an initial stage of the process that a plug is pulled out from a socket in a prior art. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present invention will be explained with reference to the attached drawings. In the illustrated embodiments, the same members as those of the prior art (Patent Document 1) are designated by the same reference numerals. In the illustrated embodiments, the safety joint entirely represented by the reference numeral  100  has a socket  20  which is a filling apparatus side member and a plug  10  which is a nozzle side member. First, the first embodiment will be described with reference to  FIGS. 1, 2 and 3 . In  FIG. 1  showing a state in which the plug  10  (nozzle side member) and the socket  20  (filling apparatus side member) are connected, the plug  10  with a cylindrical shape as a whole has a plug body  1  and a plug side protruding member  3  projecting to the socket  20  side (left side in  FIG. 1 ). In the state shown in  FIG. 1  in which the plug  10  and the socket  20  are connected, the plug side protruding member  3  is inserted into an opening  21 C formed in a socket body  21 . A hydrogen gas supply port  1 B (hydrogen gas outlet) is provided at an end of the plug body  1  on the vehicle side (right side in  FIG. 1 : the side separated from the socket  20  side), and the hydrogen gas outlet  1 B is connected to a filling hose  201  (see  FIG. 14 : not shown in  FIG. 1 ). 
     An in-plug flow path  1 A is formed in the central portion, in the vertical direction, of the plug body  1  and the plug side protruding member  3 , and the in-plug flow path  1 A extends in the axial direction of the plug  10  (longitudinal direction: left-right direction in  FIG. 1 ). The plug side valve body accommodating portion  1 C, which is an expanded area, is provided in the in-plug flow path  1 A. The in-plug flow path  1 A communicates from the flow path in the plug side protruding member  3  (internal space  3 B of the plug side protruding member  3 ) with the hydrogen gas outlet  1 B via the flow path in the plug side valve body accommodating portion  1 C, in other words, the in-plug flow path  1 A includes the internal space  3 B of the plug side protruding member  3  and the flow path in the plug side valve body accommodating portion  1 C. A hole  3 A is formed in the plug side protruding member  3 , and the hole  3 A communicates the in-plug flow path  1 A and the in-socket flow path  21 A with each other. The plug side rod  2  is housed in the in-plug flow path  1 A. A plug side valve body  6  is provided at the end of the plug side rod  2  on the side separated from the socket  20  (on the right side in  FIG. 1 ), and the plug side valve body  6  is housed in the valve body accommodating portion  1 C. In the valve body accommodating portion  1 C, a plug side spring  4  (elastic material) is arranged on the side of the plug side valve body  6  separated from the socket  20  (on the right side in  FIG. 1 ), and the plug side spring  4  urges the plug side valve body  6  to the socket  20  side (left side in  FIG. 1 ). The plug side valve body  6  and a valve seat  1 F form a plug side shutoff valve  5 , and the valve seat  1 F is composed of a tapered portion of the valve body accommodating portion  1 C. The plug side shutoff valve  5  has a function of shutting off or opening the in-plug flow path  1 A. As shown in  FIG. 1 , when the plug  10  and the socket  20  are connected, the plug side shutoff valve  5  is opened, and the in-plug flow path  1 A communicates with the in-socket flow path  21 A. 
     In  FIG. 1 , a groove for a locking ball  7  is formed near the tip of the plug side protruding member  3  on the socket  20  side (left side in  FIG. 1 ) to hold the locking ball  7 . An annular ball accommodating space  21 F is formed on the socket  20  side (socket body  21 ), and the ball accommodating space  21 F accommodates the locking ball  7  when the connection between the plug  10  and the socket  20  is released. The plug side rod  2  connected to the plug side valve body  6  extends to the socket  20  side (left side in  FIG. 1 ), and a flat plate member  2 A is provided at the tip on the socket  20  side. In the state where the plug  10  and the socket  20  are connected, the flat plate member  2 A is in contact with the locking ball  7  (the portion of the plug side protruding member  3  protruding into the internal space  3 B). In the state shown in  FIG. 1 , the locking ball  7  is not located in the annular ball accommodating space  21 F, so that the flat plate member  2 A cannot move to the side (socket  20  side: left side in  FIG. 1 ) separated from the plug  10  beyond the locking ball  7 , and the plug side rod  2  does not move from the position where it comes into contact with the locking ball  7  to the socket  20  side (left side in  FIG. 1 ) against the elastic repulsive force of the plug side spring  4 . As a result, in the state shown in  FIG. 1  where the plug  10  and the socket  20  are connected, the plug side valve body  6  is held in a state of being separated from the plug valve seat  1 F, and the shutoff valve  5  on the plug  10  side is held in the open state. A plug member  3 J integrally configured with the plug side protruding member  3  is provided on the side of the opening  21 C on the socket side separated from the plug  10  (on the left side in  FIG. 1 ). In  FIG. 1 , reference symbol SS is a seal member (for example, an O-ring). 
     In  FIG. 1 , in the socket body  21  of the socket  20  with a cylindrical shape as a whole, at the end of the hydrogen filling apparatus (not shown) side (upper side in  FIG. 1 ), a hydrogen gas introduction port  21 B for introducing hydrogen gas supplied from the hydrogen filling machine is provided. The hydrogen gas introduction port  21 B is provided with a plug member  31  having a flow path inside. The socket body  21  is formed with an in-socket flow path  21 A extending in the vertical direction in  FIG. 1 . A socket side valve body accommodating portion  21 D, which is an expanded area, is formed in the in-socket flow path  21 A, and a socket side valve body  25  is accommodated in the socket side valve body accommodating portion  21 D. In the in-socket flow path  21 A, the region on the side (lower side of  FIG. 1 ) of the socket side valve accommodating portion  21 D separated from the hydrogen gas introduction port  21 B constitutes a socket side rod accommodating portion  21 G. 
     In  FIG. 1 , the socket  20  includes a socket side rod  22  (filling apparatus side rod-shaped member), a socket side valve body  25  integrally connected to the hydrogen filling apparatus side (upper in  FIG. 1 ) of the socket side rod  22  and a socket side spring  23  arranged on the hydrogen gas introduction port  21 B side (upper in  FIG. 1 ) of the socket side valve body  25 , and the socket side rod  22 , the socket side valve body  25 , and the socket side spring  23  are housed in the in-socket flow path  21 A (internal space of the socket body  21 ). Here, the socket side spring  23  urges the socket side valve body  25  to be separated from the hydrogen gas introduction port  21 B (lower side in  FIG. 1 ). The socket side valve body  25  and the valve seat  21 E constitute the socket side shutoff valve  24 , and the valve seat  21 E is composed of the tapered portion of the valve body accommodating portion  21 D. The socket side shutoff valve  24  has a function of shutting off or opening the in-socket flow path  21 A. As is clearly shown in  FIG. 2 , the socket side rod  22  is supported (mounted) by the support member  26  (rod support member). In  FIG. 2 , the support member  26  has a disk-shaped member  26 D ( FIG. 2 ), and the disk-shaped member  26 D is rotatably supported around a rotation center  26 E on a socket body  21 . The disk-shaped member  26 D is provided with a protrusion  26 A and a notch  26 B, and the notch  26 B has a flat portion  26 C. The protrusion  26  is engaged with (inserted into) the opening  3 C (groove) formed in the plug side protruding member  3 . In the state where the plug  10  and the socket  20  are connected (the state of  FIGS. 1 and 2 ), the notch  26 B of the disc-shaped member  26 D is located on the socket side valve body  25  side (upper side in  FIGS. 1 and 2 ), and the end of the socket side rod  22  on the plug side protruding member  3  side (lower side in  FIGS. 1 and 2 ) is in contact with the flat portion  26 C and supported (placed) thereon. Since the protrusion  26 A of the disc-shaped member  26 D is engaged with the opening  3 C, the disc-shaped member  26 D does not rotate, and the socket side rod  22  is supported (mounted) on the flat portion  26 C, so that the socket side rod  26  holds the socket side valve body at a position separated from the valve seat  21 E as shown in  FIGS. 1 and 2  against the elastic repulsive force of the socket side spring  23  and the socket side shutoff valve  24  is maintained in an open state. 
     As shown in  FIG. 1 , when the plug  10  and the socket  20  are connected, the socket side shutoff valve  24  is open. At that time, the in-socket flow path  21 A communicates the hydrogen gas introduction port  21 B with the opening portion  21 C (through hole) of the socket body  21  via the socket side valve body accommodating portion  21 D, the socket side rod accommodating portion  21 G, and the annular ball accommodating space  21 F. The in-socket flow path  21 A communicates with the in-plug flow path  1 A via a hole  3 A formed in the plug side protruding member  3 . The hydrogen gas that has flowed into the safety joint  100  from the hydrogen gas introduction port  21 B flows to the hydrogen gas supply port  1 B through the communication passages, and flows through the filling hose  201  ( FIG. 14 ). 
     In  FIG. 1 , for example, when a fuel cell vehicle (FCV) not shown during hydrogen filling suddenly starts and a large tension acts on the filling hose, as shown by the arrow Q, a force that causes the plug  10  to come out of the socket  20  acts. When the tension is equal to or higher than a predetermined value, the plug  10  moves in the direction of the arrow Q, and the connection between the plug  10  and the socket  20  is disconnected. However, the first embodiment shown in  FIGS. 1 to 3  has a function of immediately shutting off the socket side shutoff valve  24  in such a case. The support member  26  in the socket  20  changes to a state in which the socket side rod  22  is not supported (placed) when the plug  10  is disengaged from the socket  20 . 
     As described above, since the protrusion  26 A of the disc-shaped member  26 D is engaged with the groove  3 C of the plug side protruding member  3 , when the plug  10  moves in the arrow Q direction with respect to the socket  20 , the disc-shaped member  26 D rotates in the direction of the arrow R ( FIG. 2 ). When the disk-shaped member  26 D rotates in the direction of the arrow R, the flat portion  26 C of the notch  26 B of the disk-shaped member  26 D moves from the horizontal position on the socket side valve body  25  side (upper side in  FIGS. 1 and 2 ) to a non-horizontal position as shown in  FIG. 3  (position shown in  FIG. 3 : the flat portion  26 C is the position on the left side of the disk-shaped member  26 D), so that the socket side rod  22  is no longer placed (supported) on the flat portion  26 C. The socket side rod  22  that is no longer placed (supported) on the flat portion  26 C of the disk-shaped member  26 D cannot resist the elastic repulsive force of the socket side spring  23  and moves (falls) to the plug side protruding member  3  (lower side in  FIGS. 1 to 3 ). When the socket side rod  22  falls, the socket side valve body  25  is pressed by the elastic repulsive force of the socket side spring  23  and instantly sits on the valve seat  21 E, and the socket side shutoff valve  24  is closed. That is, when the plug  10  moves in the direction of the arrow Q and the disk-shaped member  26 D rotates in the direction of the arrow R, the socket side rod  22  supported by the flat portion  26 C of the notch  26 B of the disk-shaped member  26 D of the support member  26  instantly moves (downs) to the plug side protruding member  3  side, so that as shown in  FIG. 3 , the socket side shutoff valve  24  is instantly closed at the initial stage when the plug  10  is disconnected from the socket  20 . Closing the socket side shutoff valve  24  prevents hydrogen gas flowing into the in-socket flow path  21 A from the gas introduction port  21 B from flowing out to the outside of the socket  20 . 
     As described above, in the state of  FIG. 1  (the state in which the plug  10  and the socket  20  are connected), the flat plate-shaped end  2 A of the plug side rod  2  is in contact with the locking ball  7 , so that it is not possible to move from the state shown in  FIG. 1  in the extension direction of the plug side spring  4  (to the left in  FIG. 1 ). In  FIG. 1 , when the plug  10  starts to come out of the socket  20 , the plug  10  moves in the direction of the arrow Q, and the locking ball  7  also moves in the direction of the arrow Q (to the right in  FIG. 1 ) to reach the position of the annular ball accommodating space  21 F. When the locking ball  7  reaches the position of the annular ball accommodating space  21 F, the locking ball  7 , which is pressed by the elastic repulsive force of the plug side spring  4 , moves outward in the radial direction (vertical direction in  FIG. 1 ) to enter the annular ball accommodating space  21 F ball storage space  21 F. When the locking ball  7  enters the annular ball accommodating space  21 F, the locking ball  7  does not project into the internal space  3 B of the plug side protruding member  3 , so that the locking ball  7  does not prevent the end portion  2 A of the plug side rod  2  from moving in the extension direction (leftward direction in  FIG. 1 ) of the plug side spring  4 . As a result, as shown in  FIG. 3 , the plug side valve body  6  moves in the extension direction (leftward in  FIGS. 1 and 3 ) due to the elastic repulsive force of the plug side spring  4 , and sits on the valve seat  1 F, thereby the plug side shutoff valve  5  is closed, and high-pressure hydrogen gas existing in the in-plug flow path  1 A is prevented from flowing out to the outside of the plug  10 . That is, as shown in  FIG. 3 , when the connection between the plug  10  and the socket  20  is released in the safety joint  100  according to the first embodiment, the plug side shutoff valve  5  and the socket side shutoff valve  24  are instantly closed, and hydrogen gas is prevented from flowing out to the outside of the plug  10  or the outside of the socket  20 . 
     Next, the second embodiment of the present invention will be described with reference to  FIGS. 4 to 7 . In the explanation of the second embodiment shown in  FIGS. 4 to 7 , parts which are different from those of the first embodiment shown in  FIGS. 1 to 3  will be mainly described. In the second embodiment, although the mechanism that immediately shuts off the socket side shutoff valve  24  when the connection between the plug  10  and the socket  20  is disconnected includes a support member  27  (rod support member) that supports (places) the socket side rod  22 , the support member  27  is different from the support member  26  of the first embodiment shown in  FIGS. 1 to 3 . The support member  27  in the second embodiment shown in  FIGS. 4 to 7  moves together with the plug  10  when the plug  10  is disengaged from the socket  20 , and changes to a state in which the socket side rod  22  is not supported (not mounted). 
     As shown in  FIG. 5 , the support member  27  has a rod mounting member  27 D and a deformation member  27 F, and the rod mounting member  27 D has a protrusion  27 A, a flat portion  27 B, and an inclined portion  27 E having a shape complementary to the inclined portion  27 C of the rod mounting member  27 D. In  FIG. 5 , the deformation member  27 F is located on the plug body  1  side (right side in  FIG. 5 ) with respect to the rod mounting member  27 D, and is attached to the socket body  21  ( FIG. 4 ). Further, the plug side protruding member  3  is formed with an opening  3 D (groove) with which the protrusion  27 A of the rod mounting member  27 D is engaged. Further, an opening  21 C (through hole) is formed in the socket  20 , a plug side protruding member  3  is inserted into the opening  21 C, and the opening  21 C is formed so as to extend in a direction orthogonal to the in-socket flow path  21 A. In the opening  21 C, a large diameter portion  21 H is formed in a region on the plug  10  side (right side in  FIGS. 4 and 5 ) with respect to the in-socket flow path  21 A. In the state where the plug  10  and the socket  20  are connected (the states shown in  FIGS. 4 and 5 ), the flat portion  27 B of the rod mounting member  27 D is located directly below the socket side rod  22  in  FIGS. 4 and 5 , so that the end of the socket side rod  22  on the plug side protruding member  3  side (lower side in  FIGS. 4 and 5 ) is supported (mounted) on the flat portion  27 B in a horizontal state. Since the protrusion  27 A of the rod mounting member  27 D is engaged with the opening  3 D, the rod mounting member  27 D does not move to the plug  10  side (right side in  FIGS. 4 and 5 ) in the states of  FIGS. 4 and 5 , and the state in which the socket side rod  22  is supported (mounted) on the flat portion  27 B is maintained, so that the socket side rod  22  keeps the socket side valve body  25  separated from the valve seat  21 E against the elastic repulsive force of the socket side spring  23 , and the socket side shutoff valve  24  is open. 
     In the state shown in  FIG. 4 , the hydrogen gas flowing in from the hydrogen gas introduction port  21 B flows into the opening portion  21 C (through hole) of the socket body  21  via the socket side valve accommodating portion  21 D of the hydrogen gas introduction port  21 B, the open socket side shutoff valve  24 , the socket side rod accommodating portion  21 G, and the annular ball accommodating space  21 F, the hydrogen gas flows through the in-plug flow path  1 A through the hole  3 A formed in the plug side protruding member  3 , and flows from the hydrogen gas outlet  1 B into the filling hose  201  ( FIG. 14 ). Here, similarly to the first embodiment shown in  FIGS. 1 to 3 , when the plug  10  and the socket  20  are connected, the plug side shutoff valve  5  is open, and the in-plug flow path  1 A communicates the hydrogen gas outlet  1 B with the flow path in the plug side protruding member  3  (internal space  3 B of the plug side protruding member  3 ) via the flow path in the plug side valve body accommodating portion  1 C. 
     In  FIGS. 4 and 5 , the protrusion  27 A on the lower side of the rod mounting member  27 D of the support member  27  (rod support member) is engaged with the groove  3 D (opening) of the plug side protrusion member  3 . With this, when the connection between the plug  10  and the socket  20  is disconnected and the plug  10  moves in the direction of the arrow Q (to the right in  FIGS. 4 and 5 ), together with the plug  10 , the protrusion  27 A and the rod mounting member  27 D also move in the direction of the arrow Q (on the right side in  FIG. 4 ). When the rod mounting member  27 D moves in the direction of the arrow Q (on the right side in  FIG. 4 ) and the flat portion  27 B of the rod mounting member  27 D no longer exists at a position directly below the socket side rod  22 , the socket side rod  22  moves (descents) to the plug side protruding member  3  side (lower side in  FIG. 4  and  FIG. 5 ) by the elastic repulsive force of the socket side spring  23 . When the socket side rod  22  descends, the socket side valve body  25  is pressed by the elastic repulsive force of the socket side spring  23  and instantly sits on the valve seat  21 E, and the socket side shutoff valve  24  is instantly closed. In this way, when the rod mounting member  27 D moves in the direction of the arrow Q (to the right in  FIG. 4 ), the socket side rod  22  supported by the flat portion  27 B of the rod mounting member  27 D of the support member  26  immediately moves (descends) to the plug side protruding member  3  side (lower side in  FIGS. 4 and 5 ), so that the socket side shutoff valve  24  is instantly closed at the initial stage when the plug  10  is disengaged from the socket  20 . The hydrogen gas that has flowed into the in-socket flow path  21 A from the gas introduction port  21 B is blocked by the socket side shutoff valve  24  so that the hydrogen gas does not flow out to the outside of the socket  20 . Such a state is shown in  FIGS. 6 and 7 . 
     In  FIG. 6 , which shows the initial state in which the plug  10  is disengaged from the socket  20 , when the plug  10  further moves in the direction of the arrow Q, if the rod mounting member  27 D does not rotate toward the arrow W in  FIG. 6  and does not move in the direction of being accommodated in the large diameter portion  21 H ( FIGS. 4 and 5 ), the rod mounting member  27 D keeps the state of being fitted in the groove  3 D (opening) of the plug side protruding member  3 , and when the plug  10  further moves to the side where the plug  10  comes off with respect to the socket  20  (right side in  FIGS. 4 to 7 ), the rod mounting member  27 D interferes with other members, and it becomes a so-called “bitten” state (locked state), and there is a risk that the plug  10  will not come off the socket  20 . According to the second embodiment shown in  FIGS. 4 to 7 , when the plug  10  moves in the direction of the arrow Q, as shown in  FIG. 6 , the inclined portion  27 C (tapered portion) of the rod mounting member  27 D comes into contact with the inclined portion  27 E (tapered portion,  FIG. 5 ) of the deformation member  27 F ( FIG. 5 ), as the plug  10  moves in the direction of the arrow Q, the inclined portion  27 C is guided by the tapered portion  27 E, and the rod mounting member  27 D moves to the plug  10  side (right side in  FIG. 6 ). Guiding the inclined portion  27 C by the tapered portion  27 E allows the rod mounting member  27 D ( FIG. 5 ) to ride on the tapered portion  27 E ( FIG. 5 ) of the deformation member  27 F ( FIG. 5 ). When the rod mounting member  27 D rides on the tapered portion  27 E of the deformation member  27 F, the rod mounting member  27 D rotates in the arrow W direction ( FIG. 6 ) about the edge P ( FIG. 6 ) of the groove  3 D of the plug side protruding member  3 . Rotating in the direction of the arrow W, the rod mounting member  27 D moves so as to be accommodated in the large diameter portion  21 H. Since when rotating in the direction of the arrow W, the protrusion  27 A of the rod mounting member  27 D comes off from the groove  3 D (opening), even if the plug  10  moves in the direction of the arrow Q, the rod mounting member  27 D does not move in the direction of the arrow Q, so that the rod mounting member  27 D does not interfere with other members to form a so-called “bitten” state. Then, the plug  10  is smoothly disengaged (comes out) from the socket  20  (on the right side in  FIGS. 4 to 7 ). 
     In the second embodiment shown in  FIGS. 4 to 7 , the opening and closing of the plug side shutoff valve  5  by the plug side valve body  6  is the same as that of the first embodiment shown in  FIGS. 1 to 3 . In the state of  FIG. 4  in which the plug  10  and the socket  20  are connected, since the flat plate-shaped end  2 A of the plug side rod  2  is in contact with the locking ball  7 , the rod end  2 A does not move to the side (left side in  FIG. 4 ) separated from the plug body  1  from the locking ball  7 , and since the plug side valve body  6  is held in a state of being separated from the plug valve seat  1 F, the plug side shutoff valve  5  is in an open state. On the other hand, when the plug  10  starts to come out of the socket  20  and the plug  10  moves in the direction of the arrow Q, the locking ball  7  also moves in the direction of the arrow Q (right), when reaching the ball accommodating space  21 F, the locking ball  7  enters the ball accommodating space  21 F and does not protrude into the internal space  3 B of the plug side protruding member  3 . As a result, the locking ball  7  does not prevent the end  2 A of the plug side rod  2  from moving to the side separated from the plug body  1  (left side in  FIG. 4 ), and the plug side valve body  6  moves in the extension direction of the plug side spring  4  (to the left in  FIG. 4 ). Then, the plug side valve body  6  is instantly seated on the plug valve seat  1 F by the elastic repulsive force of the plug side spring  4 , and the plug side shutoff valve  5  is closed. 
     Closing the plug side shutoff valve  5  prevents hydrogen gas from flowing out from the plug  10 . The states in which the socket side shutoff valve  24  and the plug side shutoff valve  5  are closed are shown in  FIGS. 6 and 7 . In  FIG. 7 , which shows a state in which the plug  10  is completely disconnected from the socket  20 , the rod mounting member  27 D and the deformation member  27 F are housed in the large diameter portion  21 H formed in the socket body  21 . 
     According to the safety joint  100 - 1  shown in  FIGS. 4 to 7 , since the support member  27  has the rod mounting member  27 D and the deformation member  27 F and when the plug  10  and the socket  20  are connected, the end portion of the socket side rod  22  contacts with the flat portion  27 B of the rod mounting member  27 D and is supported (mounted) thereon, the socket side valve body  25  is held in an open state against the elastic repulsive force of the socket side spring  23 . In the safety joint  100 - 1 , the movement of the plug  10  to be disengaged from the socket  20  is transmitted to the rod mounting member  27 D via the groove  3 D of the plug side protruding member  3  and the protrusion  27 A of the rod mounting member  27 D, if the rod mounting member  27 D moves together with the plug  10 , the end portion of the socket side rod  22  is not supported (mounted) on the flat portion  27 B of the rod mounting member  27 D, and the socket side valve body  25  instantly sits on the valve seat due to the elastic repulsive force of the socket side spring  23 . Here, when the plug  10  comes off from the socket  20 , the inclined portion  27 C of the rod mounting member  27 D comes into contact with the inclined portion  27 E of the deformation member  27 F, the rod mounting member  27 D rides on the inclined portion  27 E of the deformation member  27 F, and the rod mounting member  27 D rotates around the edge P in the groove  3 D of the plug side protruding member  3  in the direction of the arrow W in  FIG. 6 , and is housed in the large diameter portion  21 H. Accommodating the rod mounting member  27 D in the large diameter portion  21 H prevents that the rod mounting member  27 D interferes with other members and becomes a so-called “bitten” state, and the plug  10  smoothly comes off from the socket  20 . Other configurations and operational effects of the safety joint  100 - 1  of the second embodiment are the same as those of the safety joint  100  of the first embodiment shown in  FIGS. 1 to 3 . 
     Next, the third embodiment of the present invention will be described with reference to  FIGS. 8 to 12 . The safety joint  100 - 2  of the third embodiment shown in  FIGS. 8 to 12  has a support member (rod support member) different from that of the safety joint  100  of the first embodiment and the safety joint  100 - 1  of the second embodiment. In the following description of the third embodiment, parts different from the first embodiment and the second embodiment will be mainly described. In  FIG. 8  showing a state in which the plug  10  and the socket  20  are connected, the socket  20  includes a support member  28  that supports (places) the socket side rod  22  in addition to the socket side valve body  25 , the socket side spring  23 , and the socket side rod  22 , and is configured to immediately shut off the socket side shutoff valve  24  when the connection between the plug  10  and the socket  20  is disconnected. Then, the support member  28  is configured to move (operate) together with the plug  10  when the plug  10  is disengaged from the socket  20  so as not to support (place) the socket side rod, and thereby to shut off the socket side shutoff valve  24 . 
     In  FIG. 9 , which shows an enlarged view of the support member  28 , the support member  28  (rod support member) arranged adjacent to the ball  29  has an annular portion  28 A and a ball holding portion  28 B that hold the ball  29  in between, and the annular portion  28 A and the ball holding portion  28 B are integrally configured. The ball holding portion  28 B is arranged on the plug  10  side (right side in  FIGS. 8 and 9 ) with respect to the annular portion  28 A, and holds the ball  29  in the hollow portion. The ball holding portion  28 B is provided with openings smaller than the diameter of the ball  29  on both sides (bottom surface and top surface) of the plug side protruding member  3  in the radial direction (vertical direction shown in  FIGS. 8 and 9 ). In the radial direction of the plug side protruding member  3 , although a part of the ball  29  protrudes from the ball holding portion  28 B, the small-diameter opening is configured so that the entire ball  29  does not come out of the ball holding portion  28 B. In  FIG. 9 , the plug side protruding member  3  is formed with a recess  3 E (groove) into which a part of the ball  29  is engaged (inserted). In  FIGS. 8 and 9 , an opening  21 C (through hole) into which the plug side protruding member  3  is inserted is formed in the socket  20  so as to extend in a direction orthogonal to the in-socket flow path  21 A, and a large diameter portion  21 I is formed in the region of the opening  21 C on the plug  10  side of the in-socket flow path  21 A. When the plug  10  and the socket  20  are connected as shown in  FIG. 8 , an end portion of the socket side rod  22  is in contact with the annular portion  28 A and is supported (placed) thereon. As a result, the socket side valve body  25  is held in a state of being separated from the valve seat  21 E, and the socket side shutoff valve  24  is open. When the plug  10  and the socket  20  are connected, a part of the ball  29  held by the ball holding portion  28 B engages with the groove  3 E (recess) of the plug side protruding member  3 , the portion of the ball  29  opposite to the portion engaged with the groove  3 E (outward in the radial direction of the plug side protruding member  3 ) is in contact with the inner wall surface of the opening  21 C of the socket body  21 , so that the ball  29  cannot move outward from the radial direction of the plug side protruding member  3  (vertical direction in  FIGS. 8 and 9 ). 
     As described above, when the plug  10  and the socket  20  are connected as shown in  FIG. 8 , the socket side shutoff valve  24  is opened, and the hydrogen gas introduction port  21 B of the in-socket flow path  21 A communicates with the opening portion  21 C of the socket body  21  via the socket side valve body accommodating portion  21 D, the socket side rod accommodating portion  21 G, and the annular ball accommodating space  21 F. Then, the hydrogen gas introduction port  21 B communicates with the in-plug flow path  1 A via the hole  3 A formed in the plug side protruding member  3 . Similar to the first and second embodiments shown in the figures, the plug side shutoff valve  5  is opened when the plug  10  and the socket  20  are connected, and the in-plug flow path  1 A communicates with the hydrogen gas outlet  1 B via the internal space  3 B of the plug side protruding member  3  and the flow path in the plug side valve body accommodating portion  1 C. As a result, the hydrogen gas flowing in from the hydrogen gas introduction port  21 B flows out from the hydrogen gas outlet  1 B and flows through the filling hose  201  (see  FIG. 14 ). 
     Since when the plug  10  and the socket  20  are connected, a part of the ball  29  is engaged with the groove  3 E (recess) of the plug side protruding member  3 , as shown in  FIG. 10 , when the connection between the plug  10  and the socket  20  is released and the plug  10  moves in the direction away from the socket  20  (direction of the arrow Q), along with the ball  29 , the annular portion  28 A and the ball holding portion  28 B of the rod support member  28  also move (rightward) in the arrow Q direction (rightward in  FIGS. 8 and 9 ). When the rod support member  28  moves in the direction of the arrow Q, the socket side rod  22  mounted (supported) on the annular portion  28 A of the rod support member  28  is no longer mounted on the annular portion  28 A and immediately moves (drops) to the opening  21 C side due to the elastic repulsive force of the socket side spring  23 . When the socket side rod  22  falls, the socket side valve body  25  is pressed by the socket side spring  23  and instantly sits on the socket side valve seat  21 E, and the socket side shutoff valve  24  is immediately closed. 
     In other words, the socket side rod  22  supported by the annular portion  28 A in a state where the plug  10  and the socket  20  are connected, when the plug  10  starts to come off from the socket  20 , the rod support member  28  moves in the direction of the arrow Q (to the right in  FIG. 10 ), and immediately disengages from the annular portion  28 A and falls toward the opening  21 C, so that the socket side shutoff valve  24  is instantly closed at the initial stage when the plug  10  is disconnected from the socket  20 . Closing the socket side shutoff valve  24  prevents hydrogen gas flowing into the socket  20  from flowing out to the outside of the socket  20 . Then, by the same mechanism as in the first embodiment and the second embodiment, at the initial stage when the plug  10  is disengaged from the socket  20 , the plug side shutoff valve  5  is instantly closed to prevent hydrogen gas from flowing out to the outside of the plug  10 . With this, in the third embodiment shown in  FIGS. 8 to 12 , in the initial stage when the plug  10  comes off the socket  20 , since the socket side shutoff valve  24  and the plug side shutoff valve  5  are closed instantaneously, hydrogen gas is prevented from flowing out from the safety joint  100 - 2 . 
     In  FIG. 10  showing the initial state in which the plug  10  is disengaged from the socket  20 , as a result of the plug  10  moving in the direction of the arrow Q with respect to the socket  20 , the ball  29  reaches the large diameter portion  21 I. Moving the plug  10  in the direction of the arrow Q causes the ball  29  to be pressed by the annular portion  28 A and the inner wall surface of the large diameter portion  21 I, so that the ball  29  that has reached the large diameter portion  21 I due to the pressing force moves outward in the radial direction (vertical direction in  FIGS. 9 and 10 ), and is removed from the groove  3 E (recess:  FIG. 9 ) of the plug side protruding member  3  and is housed in the large diameter part  21 I. At that time, the ball holding portion  28 B contacts with the inner wall surface of the large diameter portion  21 I. As a result of the ball  29  being disengaged from the groove  3 E (recess) and accommodated in the large diameter portion  21 I, since the rod support member  28  (annular portion  28 A and ball holding portion  28 B) moves relative to the plug  10  (becomes movable relative to the plug  10 ), the rod support member  28  does not interfere with (the movement: the movement in the direction of the arrow Q in  FIG. 10 ) of the plug  10 , the ball  29  does not interfere with the plug  10 , and as shown in  FIGS. 11 and 12 , the plug  10  can move in the direction of the arrow Q and can be disengaged from the socket  20 . 
     Here, since the plug  10  is instantly pulled out of the socket  20 , the state of  FIG. 10  is instantly changed to the state of  FIG. 11 , and the state of  FIG. 11  is instantly changed to the state of  FIG. 12  also. In the state of  FIG. 11 , the tip of the plug side protruding member  3  is slightly inserted into the opening  21 C of the socket body  21 , and the hydrogen gas existing in the space from the socket side shutoff valve  24  to the opening  21 C is discharged from the end of the opening  21 C on the side separated from the plug  10  (left side of  FIGS. 11 and 12 ). Then, as the hydrogen gas is released, as shown in  FIG. 12 , the ball  29  and the rod support member  28  (circular part  28 A, ball holding part  28 B) move to the annular space  21 F on the side separated from the plug  10  in the opening  21 C. Other configurations and operational effects in the third embodiment shown in  FIGS. 8 to 12  are the same as those of the embodiments shown in  FIGS. 1 to 7 . 
     A modified example of the illustrated embodiment will be described with reference to  FIG. 13 . In  FIG. 13 , a silencer  30  is provided on the side (left side in  FIG. 13 ) of the opening portion  21 C of the socket body  21  separated from the plug  10 . Providing the silencer  30  allows the noise when the plug  10  comes out of the socket  20  to be reduced. In  FIG. 13 , although the silencer  30  is provided in the third embodiment shown in  FIGS. 8 to 12 , the silencer  30  can also be provided in the first embodiment shown in  FIGS. 1 to 3  and the second embodiment shown in  FIGS. 4 to 7 . 
     Since the embodiments shown in the drawings are merely examples, and the embodiments do not limit the technical scope of the present invention. 
     DESCRIPTION OF THE REFERENCE NUMERALS 
     
         
           1  plug body 
           1 A in-plug passage 
           2  plug side rod 
           3  plug side protruding member 
           3 C groove (opening, groove of plug side protruding member) 
           3 D groove (opening, groove of plug side protruding member) 
           3 E recess (opening, recess of plug side protruding member) 
           4  plug side spring (elastic member) 
           5  plug side shutoff valve 
           6  plug side valve body 
           10  plug (nozzle side member) 
           20  socket (filling apparatus side member) 
           21  socket body 
           21 A in-socket passage 
           21 C opening (through hole) 
           21 H,  21 I large diameter portions 
           22  socket side rod (rod-shaped member) 
           23  socket side spring (elastic member) 
           24  socket side shutoff valve 
           25  socket side valve body 
           26 ,  27 ,  28  rod support members 
           26 A protrusion 
           26 B notch 
           26 C flat portion 
           26 D disk-shaped member 
           27 A protrusion 
           27 B flat portion 
           27 C taper portion (inclined portion) 
           27 D rod mounting portion 
           27 E inclined portion 
           27 F deformation member 
           28 A circular portion 
           28 B ball holding portion 
           29  ball 
           100 ,  100 - 1 ,  100 - 2  safety joints