Abstract:
The male or female element according to the invention is equipped with a closure valve intended to be manoeuvred by the other element of the connection. It further comprises a member defining, alone or with the body of this element, a globally annular section in recess of which parts of the valve are capable of receiving, in abutment, a part of the other element of the connection for manoeuvring the valve to open it. The ratio of the width of the aforementioned annular section to the depth of recess of the aforementioned parts with respect to this section is less than 1. This limits the access to the valve and avoids accidental manoeuvres thereof.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a male or female element of a quick connection, as well as to a quick connection comprising, inter alia, such an element.  
       BACKGROUND OF THE INVENTION  
       [0002]     In the domain of handling fluid under pressure, it is known, for example from EP-A-0 969 239, to equip each of the male and female elements of a quick connection with a closure valve controlled by the other element of the connection, with the result that the fit of the elements of the connection in each other induces a manoeuvre of the valves in the sense of opening. This type of connection gives satisfaction in the majority of cases and, to a large extent, limits the risks of leakage during the successive openings/closures of the connection. However, when the male and female elements of the connection are disconnected, the valve is flush with the pusher which it surrounds and an effort exerted accidentally on the exposed face of the valve of one of these elements may lead to moving it away from its seat, with the result that a risk of leakage cannot be excluded.  
         [0003]     It is also known from GB-A-732 186 to equip the valve of a female element of a quick connection with a rod on which is mounted a washer supporting a seal which receives the end of a male connector in abutment. An accidental or fraudulent abutment on the end of the rod may result in an untimely opening of the valve, while the seal is only slightly recessed with respect to the front end of the rod, with the result that it risks being struck or displaced during an operation other than the positioning of the male connector.  
         [0004]     It is also known from GB-A-979 821 to use a valve whose front face is flush with that of a pusher that this front face surrounds. This front face is easily accessible, with the result that the risks of accidental or fraudulent manipulation of the valve in the sense of opening it cannot be excluded.  
         [0005]     Now, in certain applications, dangerous fluids may circulate in a connection. For example, it may be question of hydrogen in the case of a low-pressure system for supplying fuel cells from a reservoir. In that case, it is essential to avoid a manoeuvre accidentally opening the valve of one of the elements of the connection when these elements are uncoupled.  
         [0006]     It is an object of the invention to attain this object by proposing a novel connection element of which the valve does not risk being opened accidentally in uncoupled configuration.  
       SUMMARY OF THE INVENTION  
       [0007]     In that spirit, the invention relates to a male or female element of a safety quick connection intended for removably joining pipes and/or reservoirs of fluid under pressure, this element being equipped with a closure valve intended to be manoeuvred for opening by the other element of the connection, while, when the valve is in abutment on its seat, at least one surface of the valve, intended to receive a part of the other element of the connection in abutment with a view to manoeuvring the valve to open it, is disposed recessed with respect to a globally annular transverse section for passage of the aforementioned part of the other element for manoeuvring the valve to open it. This element is characterized in that the ratio of the mean width of the globally annular section, taken in a radial direction with respect to the axis of fit of the elements of the connection, and of the depth of recess of the or each bearing surface is less than 1, preferably less than 0.3.  
         [0008]     Within the meaning of the present invention, a globally annular section or volume is a cylindrical section or volume with circular, virtually circular or polygonal base which does not extend up to its central axis.  
         [0009]     Thanks to the invention, the globally annular transverse section limits access to the volume in which the second element of the connection interacts with the valve. The value of the ratio between the mean width of the annular section and the depth of the recess of the or each bearing surface of the valve is such that these surfaces may be considered as being driven in deeply with respect to the width of the surface through which access is possible. The probabilities of a conventional object pressing against the or each surface of the valve, which are recessed, are therefore very low with respect to the known devices.  
         [0010]     According to advantageous but non-obligatory aspects, a quick connection element may incorporate one or more of the following characteristics: 
        That part of the valve which forms the bearing surface or surfaces is constituted by at least two portions separated from each or one another, with the result that they form a discontinuous bearing surface. The segmentation of the bearing surface limits the possibilities of manoeuvre insofar as the penetration of an object in the globally annular volume has little chance of inducing an effort of displacement of the valve.     When the valve is in abutment on its seat, the bearing surface or surfaces of the valve are disposed in a globally annular volume, inside the element in question and of which the aforementioned transverse section constitutes an entrance zone.     The globally annular section, and possibly volume, are defined between a central stud whose median axis is substantially parallel to the direction of fit of the elements of the connection, and a globally cylindrical surface. This central stud may project beyond the bearing surfaces, in the direction of the mouth of the element and inside the body thereof.     The ratio of the area of the bearing surface or of the sum of the areas of the bearing surfaces of the valve and of the area of the transverse section is strictly less than 1, preferably less than 0.3.     The annular section is formed in the body of the element, at a distance from its mouth.     The globally annular section is defined, at least in part, by a member added in a conduit located between the valve and the mouth of this element. In a variant, the aforementioned member extends both upstream and downstream of the valve, while the valve is provided with an opening in which a part of this member is introduced, this allowing the valve to slide around this part. In addition, this member advantageously comprises a globally annular part adapted to come into abutment against an internal surface of the body of the element, and a stud adapted to be centred on the axis of fit of the male and female elements of the connection due to the positioning of this member in this conduit, this stud and this annular part being connected by at least one centring mount.        
 
         [0017]     The invention also relates to a quick connection for an installation handling fluid under pressure which comprises two elements, male and female, and of which at least one is as described hereinabove. Such a connection is more reliable than those of the state of the art. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]     The invention will be more readily understood on reading the following description of two forms of embodiment of a connection in accordance with its principle, given solely by way of example and made with reference to the accompanying drawings, in which:  
         [0019]      FIG. 1  is an exploded longitudinal section of a female element of a quick connection according to the invention.  
         [0020]      FIG. 1A  is a side view, in the direction of arrow I in  FIG. 1 .  
         [0021]      FIG. 2  is an exploded view in perspective, with parts torn away, of the element of  FIG. 1 .  
         [0022]      FIG. 2A  is a side view, in the direction of arrow II in  FIG. 2 , of the valve shown in  FIGS. 1 and 2 .  
         [0023]      FIG. 3  is a section of the female element of  FIGS. 1 and 2  in configuration of use uncoupled from the corresponding male element of the connection.  
         [0024]      FIG. 4  is a section similar to  FIG. 3  when a male element is fitted in the female element, and  
         [0025]      FIG. 5  is a partial section of a female element of a connection, in accordance with a second form of embodiment of the invention and in the configuration of  FIG. 3 . 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENT  
       [0026]     Referring now to the drawings, the female element A of the connection, shown in FIGS.  1  to  4 , is intended to receive, fitted in the direction of an axis X-X′, a male element B partially shown in  FIG. 4 .  
         [0027]     The element A comprises a body  1  in which is defined a conduit  11  for circulation of fluid under pressure. The body  1  is provided with an internal flange  12  which divides the conduit  11  into three parts  11   a ,  11   b  and  11   c  which successively extend from the rear part  13  of the body  11 , intended to be connected to a pipe C 1 , towards the front part  14  in which is defined the mouth  11   d  of the conduit  11  through which a tubular part  101  of the male element or connector B may be introduced.  
         [0028]     In practice, each of the elements A and B may be connected to a pipe or to a reservoir of fluid under pressure.  
         [0029]     The flange  12  is provided with a bevel  12   a  which forms a tight seat for abutment of a valve  2 , of which the external surface presents a truncated part  21  whose geometry is complementary of that of the bevel  12   a.    
         [0030]     In practice, the fluid fills the parts  11   a  and  11   b  of the conduit  11  when the valve  2  is detached from the seat  12   a , while it flows in part  101  of the male connector at the level of part  11   c.    
         [0031]     According to one aspect of the invention (not shown), the valve  2  may be subjected to the action of means, such as a spring, for elastic return in closed configuration of the element A, i.e. in a configuration where the part  21  bears against the bevel  12   a . In the example shown, it is assumed that pipe C 1  is connected to a source of fluid under pressure, the pressure P 1  prevailing in part  11   a  of the conduit  11  being sufficient to apply the valve  2  against the seat or bevel  12   a  by default.  
         [0032]     A seal (not shown) is advantageously disposed in the bearing zone between the valve and the seat, this seal being able to be borne by the seat or by the valve.  
         [0033]     The valve  2  is provided with two extensions  22  and  23  intended to traverse the part  11   b  of the conduit  11  and to extend as far as in its part  11   c , as will be apparent from the following explanations.  
         [0034]     In part  11   c  of the conduit  11  there is disposed a member  3  which has the function of preventing, as far as possible, an accidental manoeuvre of the valve  2 , in the sense of opening of the element A. The member  3  is formed by two parts  3 A and  3 B between which an O-ring  4  is disposed. The part  3 A comprises an annular skirt  31  whose external surface  32  has a geometry corresponding to the internal surface  15  of the body  11 , at the level of the part  11   c  of the conduit  11 , with the result that this part  3 A may be immobilized by cooperation of shapes inside the part  11   c . Part  3 A also comprises a stud  33  connected to the skirt  31  by a centring mount  34  which extends diametrally with respect to the skirt  31 . The geometry of the part  3 A is such that, when it is in place in the conduit  11 , the stud  33  is centred on axis X-X′.  
         [0035]     Part  3 B is in the form of an annular sleeve with circular base  35  whose internal and external diameters are identical to those of the skirt  31 . The sleeve is provided with an entrance bevel  35   a  convergent in the direction of part  3 A.  
         [0036]     When element A is in the configuration of  FIG. 3 , the extensions  22  and  23  extend right through the mount  34 , up to in an annular volume V 3  defined by the member  3 , between the internal radial surface  36  of the skirt  31 , the O-ring  4  and the internal radial surface  36 ′ of the sleeve  35 , on the one hand, and the external radial surface  37  of the stud  33 , on the other hand, these surfaces being cylindrical and of circular base.  
         [0037]     Volume V 3  is shown shaded grey in  FIGS. 1 and 3 . It is defined, on its left-hand side in  FIG. 1 , by an annular transverse section S 3  which extends between the surfaces  36 ′ and  37 .  
         [0038]     In practice, the section S 3  and the volume V 3  may also be with approximately circular or polygonal, particularly hexagonal or octagonal base. It is also possible that the stud  33  be of non-circular, and even non-cylindrical section. Likewise in these cases, the section S 3  and the volume V 3  are globally annular.  
         [0039]     l 3  denotes the radial width of the section S 3  which corresponds to the distance between the surfaces  36 ′ and  37 . In the case of section S 3  not being strictly annular, l 3  is the mean radial width of this section.  
         [0040]     When the male element B is being fitted in the female element A, the tubular body  101  of the connector B may be engaged in the body  1 , through its mouth  16  made in its front face  17 , until it penetrates in the volume V 3  through the section S 3 , as shown in  FIG. 4 , in which case it may exert on the end surfaces  22   a ,  23   a  of the extensions  22  and  23  an effort F 1  of moving the valve  2  away with respect to its seat  12   a . This allows a flow of the fluid under pressure through the part  11   b  of the conduit  11  then inside the body  101 , as represented by arrows E in  FIG. 4 .  
         [0041]     The male element B is equipped with a closure valve (not shown) of which the pusher  102  then comes into abutment against the end surface  33   a  of the stud  33  which exerts on this pusher an effort F 2  of opening of this valve.  
         [0042]     In this configuration, the external radial surface of the part  101  bears against the O-ring  4 .  
         [0043]     Returning to the configuration of  FIG. 3 , it will be understood that, if the tip T A  of a tool such as a screwdriver T is introduced in the part  11   c  of the conduit  11 , there is every chance of it striking the stud  33 . In effect, the section S 3  constitutes a reduced zone of access to the surfaces  22   a  and  23   a . In addition, the tip T A  has every chance of engaging between the extensions  22  and  23  without interacting with the surfaces  22   a  and  23   a.    
         [0044]     The surfaces  22   a  and  23   a  are the only surfaces on which may be exerted an effort of the type of effort F 1  tending to move the valve  2  away from its seat  12   a . In other words, an abutment on the stud  33  disposed at the centre of the element A does not risk pushing the valve  2  towards its configuration of opening, even if the stud  33  is closer to the mouth  16  of the conduit  11  than the surfaces  22   a  and  23   a.    
         [0045]     The surface S 3  is recessed with respect to the mouth  16  of the element A, by a distance d 1  sufficient to prevent an accidental introduction of a standard tool as far as in the volume V 3 , and even to hinder the visibility of a person attempting to manipulate the valve  2  fraudulently.  
         [0046]     When the valve  2  is in abutment on its seat  12   a , the surfaces  22   a ,  23   a  are recessed in the volume V 3 , i.e. recessed with respect to the section S 3  opposite the mouth  16 , by a non-zero distance d 2 .  
         [0047]     Part  3 B of the member  3  is not indispensable and such a member may be conceived as being formed by part  3 A alone, the latter and/or the O-ring  4  in that case being configured to guide the part  101  during its introduction in the element A. In a variant, the parts  3 A and  3 B may be in one piece, the O-ring  4  being received in an internal groove of the member  3 .  
         [0048]     The ratio R 1 =l 3 /d 2  of the width l 3  with respect to the distance d 2 , is less than 1, preferably less than 0.3, and even than 0.25. In this way, the surfaces  22   a  and  23   a  penetrate in the volume V 3  deeply with respect to the section S 3  through which they are accessible. The risks of accidental or fraudulent manipulation of the valve  2  to open it are thus very substantially reduced.  
         [0049]     A 3  denotes the area of the section S 3 . A 2  denotes the sum of the areas of the surfaces  22   a  and  23   a . The ratio R 2 =A 2 /A 3  is strictly less than 1, preferably less than 0.3. In this way, the tip T A  has little chance of interfering with the surfaces  22   a  and  23   a , even if it penetrates as far as in the volume V 3 .  
         [0050]     As is more particularly apparent from  FIG. 2A , the extensions  22  and  23  are bevelled in the vicinity of their respective ends, this allowing the ratio R 2  to be reduced.  
         [0051]     In addition, taking into account the separation of the extensions  22  and  23  which must pass right through the mount  34 , the surface of the valve  2  intended to receive the effort F 1 , which is composed of the reunion of surfaces  22   a  and  23   a , is fractionated, this limiting the surface of accidental interaction with an object.  
         [0052]     According to a variant of the invention (not shown), the valve  2  may have one sole extension  22 , the ratio R 2  being reduced accordingly.  
         [0053]     In the second form of embodiment of the invention shown in  FIG. 5 , elements similar to those of the first bear identical references. The body  1  of the female element A defines a conduit  11  for circulation of fluid under pressure in which is disposed a valve  2  provided with two O-rings  24  and  25  for respective abutment on a convex transition zone  12   a  forming seat and on a cylindrical central core  33  with cured generatrix. This core belongs to a member  3  on which abuts a spring  5  for returning the valve  2  into closed configuration. The valve  2  is provided with a central opening  26  allowing it to slide around the stud  33 .  
         [0054]     An O-ring  4  is disposed in a groove  18  made in the internal radial surface  15   b  of the downstream part  11   b  of the conduit  11 . This O-ring is intended to bear against a part similar to part  101  shown in  FIG. 4 .  
         [0055]     The member  3  comprises a skirt  31  immobilized by cooperation of shapes against the surface  15   a  of the upstream part  11   a  of the conduit  11 . Centring mounts (not shown) connect the parts  31  and  33 . The stud  33  defines, with the surface  15   b  a volume V 3  in which a plurality of extensions  22  of the valve  2  extend, these extensions being regularly distributed about the central axis X-X′ of the element A and separated by interstices.  
         [0056]     As previously, the end surface  11   a  of each extension  22  is intended to receive an effort F 1  of the type of the effort of displacement of the valve  2  in a sense of opening allowing fluid under pressure to flow through the conduit  11 .  
         [0057]     The surfaces  22   a  of the extensions  22  are disposed in an annular volume V 3  accessible through an annular transverse section S 3  defined around the end  33   a  of the stud  33 . This end is flared, with the result that the radial width l 3  of the section S 3  is less than the width of the volume V 3  at the height of the ends  22   a  and this, all the more so as the surface  15   b  is provided with a radial groove  15   c  which locally increases the width of the volume V 3 . An object introduced through the section S 3  therefore has all the less chance of striking one of the ends  22   a.    
         [0058]     As previously, the ratios R 1  and R 2  are less than 1, preferably less than 0.3.  
         [0059]     The invention has been shown with a quick connection of which the male element and the female element each comprise a closure valve. However, it is applicable with a quick connection of which only the female element is provided with such a valve.