Abstract:
The coupler according to the invention comprises a male element adapted to be fitted in a female element and maintained in this position by a latch forming stop and opposing a movement of withdrawal thereof.  
     The body of the female element comprises a principal part in which is axially immobilized a secondary part connected to one of the pipes of which the coupler ensures join. Immobilization between these principal and secondary parts occurs by catches borne by the secondary part catching with complementary catches borne by the principal part.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a quick coupler for the removable join of pipes conveying fluid under pressure.  
         BACKGROUND OF THE INVENTION  
         [0002]    Patent FR-2 514 855 discloses a quick coupler which comprises two elements, male and female, adapted to fit axially, provoking the opening of a closure valve mounted in the body of the female element, this body being equipped with a loaded latch or button, mounted to slide in this body and pierced with a central opening for fit of the male element. The female element is constituted by two tubular pieces assembled on each other by screwing, which requires effecting a threading and a tapping on these pieces and that the operator who assembles this element take particular care, otherwise the thread and/or the tapping risk being distorted.  
           [0003]    The same limitations are found in the couplers known from French Patent 1 724 710 and U.S. Pat. No. 5,806,832.  
           [0004]    It is a more particular object of the present invention to overcome these drawbacks by proposing a coupler between pipes conveying fluids under pressure, of which the female element is economical and simple to assemble.  
         SUMMARY OF THE INVENTION  
         [0005]    To that end, the invention has for its first object a quick coupler for the removable join of two pipes through which a fluid under pressure passes, this coupler comprising two elements, male and female, adapted to fit axially in each other, the body of the female element comprising a principal part in which is axially immobilized a secondary part connected to one of the pipes, characterized in that immobilization between the principal and secondary parts occurs by at least one catch borne by the secondary part catching with at least one complementary catch borne by the principal part.  
           [0006]    Thanks to the invention, the assembly of the female element is economical, simple, reliable and robust, and a possible misalignment of the principal and secondary parts during assembly induces few risks of deteriorating these parts to the point of preventing their connection, while such might be the case with screwed elements.  
           [0007]    According to advantageous but non-obligatory aspects of the invention, the coupler incorporates one or more of the following characteristics:  
           [0008]    Immobilization between the principal and secondary parts occurs by several catches borne by the secondary part catching with complementary catches borne by the principal part.  
           [0009]    The catch or catches borne by the secondary part are formed on its outer radial surface.  
           [0010]    The complementary catch or catches borne by the principal part are formed on the inner radial surface of a bore for receiving the secondary part.  
           [0011]    The secondary part is immobilized axially with respect to the principal part with the possibility of rotation with respect thereto about a central axis of the female element. This makes it possible to adjust the relative angular position of these parts, particularly when the secondary part is fixed in order to facilitate access to a button for controlling a latch.  
           [0012]    A mobile closure valve is mounted in the secondary part. The latter advantageously defines a groove for receiving an O-ring for seal of this valve.  
           [0013]    An O-ring, intended to cooperate with the male element, is mounted in the secondary part, this ensuring seal when the coupler is in connected configuration.  
           [0014]    The body of the female element is equipped with a latch loaded by elastic means, mounted to slide in a housing made in the principal part and pierced with an opening for the fit of the male element or of a piece displaced by this element. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    The invention will be more readily understood on reading the following description of two forms of embodiment of a coupler according to the invention, given solely by way of example and made with reference to the accompanying drawings, in which:  
         [0016]    [0016]FIG. 1 is a longitudinal section through a coupler according to the invention in a first position where its male and female elements are coupled, the fluid circulating between these two elements.  
         [0017]    [0017]FIG. 2 is a section similar to FIG. 1, but on a smaller scale, in a second position where the male and female elements are maintained in configuration of decompression of a pipe connected on the male element by pressure on the retaining button or latch; certain elements are truncated in order to render the drawing clearer.  
         [0018]    [0018]FIG. 3 is a section similar to FIG. 1 but on a smaller scale, a blocking latch being in the same position as in FIG. 2, while a safety member blocks the latch during a phase of reduction of the pressure prevailing in the aforementioned pipe.  
         [0019]    [0019]FIG. 4 is a section similar to FIG. 2, while the safety member is in rest position, the internal pressure being low, the male element being able to be freely withdrawn from the coupler.  
         [0020]    [0020]FIG. 5 is a longitudinal section through a coupler in accordance with a second form of embodiment of the invention in a configuration similar to that of FIG. 1.  
         [0021]    [0021]FIG. 6 is a section similar to FIG. 3 and on the same scale, for the coupler of FIG. 5, and  
         [0022]    [0022]FIG. 7 is a section similar to FIG. 4 and on the same scale, for the coupler of FIGS. 5 and 6. 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0023]    Referring now to the drawings, the coupler shown in FIGS.  1  to  4  comprises a female element A and a male element or connector B connected respectively to an upstream pipe C 1  and to a downstream pipe C 2 . The upstream pipe C 1  is itself connected to a source of fluid under pressure (not shown).  
         [0024]    The outside shape of the body  1  of the female element is substantially cylindrical and circular, centred on an axis X-X′ which is also the longitudinal axis of a conduit  11  inside the body  1  and in which is arranged a valve  2  mobile along axis X-X′. The body  1  is in two parts and comprises a principal part  12  forming a bore  13  in which is immobilized a secondary part  14  fast with the pipe C 1 . In practice, the valve  2  is mounted in part  14  which defines a groove  141  for receiving an O-ring  3  for seal of the valve  2 .  
         [0025]    The outer radial surface of part  14  is provided with catches  142  and  143  intended to cooperate with catches  132  and  133  provided on the inner radial surface  134  of the bore  13 . Cooperation of the notches  132 ,  133 ,  142 ,  143  allows a firm immobilization of part  14  in the bore  13  of part  12 , these parts advantageously being made of metal.  
         [0026]    The immobilization obtained by the cooperation of notches  132 ,  133 ,  142 ,  143  is essentially axial, in that it opposes a movement of extraction of part  14  out of the bore  13 , in a direction parallel to axis X-X′.  
         [0027]    Part  14  defines a second groove  144  for receiving an O-ring  4  intended to cooperate with the outer radial surface  75  of the body  7  of the male element B.  
         [0028]    The body  1  is also provided with a housing  15  extending substantially in the direction of an axis Y-Y′ perpendicular to axis X-X′, i.e. radial. The housing  15  is made in part  12  of the body  11 . Inside the housing  15  is slidably mounted a latch  5  on which a spring  6  exerts an elastic effort F 1  directed opposite the bottom  151  of the housing  15 , i.e. in the direction of its opening  152 . The movement of the latch  5  under the effect of the effort F 1  is limited by two projections  51  and  52  coming into abutment against the edge  153  of the opening  152 . The bottom  151  of the housing  15  is provided with an orifice  154  connecting the housing  15  to the ambient atmosphere.  
         [0029]    The housing  15  intersects the conduit  11  which traverses part  12  right through.  
         [0030]    The latch  5  is provided with a transverse opening  53  centred on an axis X 5 -X′ 5  parallel to axis X-X′. The opening  53  is bordered by two teeth  54  and  55  which extend from the circumference of the opening  53  in the direction of axis X 5 -X′ 5 . Tooth  54  is the most remote from the opening  111  of the conduit  11  on the male connector B side, while tooth  55  is nearest this opening.  
         [0031]    In the configuration of FIG. 1, and in the absence of effort exerted on the latch  5  by a user, this latch is subjected to the action of the spring  6 , with the result that its tooth  54  is inserted to the rear of a shoulder  72  formed by a flange  71  provided on the periphery of the metal body  7  of the male connector B. The flange  71  is also provided with an inclined ramp  73  which is truncated and convergent in the direction of the front end  74  of the body  7 .  
         [0032]    When the coupler is to be unlocked, an effort F 2  is exerted on the latch  5 , this having the effect of retracting the tooth  54  from the path of withdrawal of the flange  71 , as shown in FIG. 2. Under the effect of the pressure prevailing in the pipe C 2 , the valve is pushed towards the O-ring  3 . The connector  7  moves along axis X-X′ in the same direction and the flange  71  comes into abutment against the tooth  55  of the latch or button  5 .  
         [0033]    The shape of the catches  132 ,  133 ,  142 ,  143  is advantageously provided so that an angular movement of parts  12  and  14  is possible about axis X-X′. This makes it possible to orient these parts angularly with respect to each other, which proves to be very practical, particularly when part  14  is fixed, for example screwed on a support. In that case, it is, in effect, possible to cause part  12  to rotate about axis X-X′ in order to orient the housing  15  in a radial direction such that access to the latch  5  is easy, in particular for application of the effort F 2 . Accessibility and manoeuvrability of the coupler are improved thereby.  
         [0034]    A piston  8  is in place in the conduit  11  of the body  1 , this piston being able to slide in the direction of axis X-X′. The piston  8  comprises a skirt  81  engaged in a housing  145  formed in part  14  and in a part  112  of the conduit  11  defined between parts  12  and  14  of the body  1 . The cooperation of the skirt  81  and of the housing  145  makes it possible to guide the piston  8  in translation.  
         [0035]    This piston  8  is provided with a central opening  82  allowing the passage of the connector  7 , with the result that the piston  8  is disposed around the connector  7 , inside the conduit  11  and in a part of this conduit defined by parts  12  and  14  in the configurations of FIGS.  1  to  4 . The fact that the body  1  is in two parts allows the piston to be placed in position and imprisoned in the conduit  11 .  
         [0036]    The opening  82  has a shape and dimensions close to the outer transverse dimensions of the front part of the connector  7 . In this way, from the configuration of FIG. 2, the fluid under pressure located in pipe C 2  flows, as represented by arrows E, around the connector  7 , in a passage  146  formed between the inner radial surface of part  14  and the outer radial surface  75  of the connector  7 , to such a point that the pressure of the fluid present in the pipe C 2  and in the connector  7  exerts on the piston  8  an effort F 3  which pushes the piston  8  in the direction of the latch  5 , in order to attain the position of FIG. 3.  
         [0037]    The latch  5  is provided with a surface  56  which is in the form of a frusto-conical sector, centred on axis X 5 -X′ 5  and convergent in the direction of the valve  2 , i.e. upstream of the coupler.  
         [0038]    As for the piston  8 , it is provided with a surface  86  likewise in the form of a frusto-conical sector, centred on axis X-X′ and convergent in the direction of upstream of the coupler. α and β respectively denote the semi-vertex angles of these surfaces  56  and  86 . Angles α and β have the same value, which is of the order of 45°.  
         [0039]    The surfaces  56  and  86  might have a geometry other than a frusto-conical sector. It might be question of parts of complementary rectilinear teeth orthogonal to axis X-X′ and provided with an oblique face with respect thereto.  
         [0040]    The displacement of the latch  5  under the effect of the effort F 2  has the effect of aligning the axis X 5 -X′ 5  on axis X-X′, with the result that, under the effect of the effort F 3 , the surface  86  of the piston  8  comes into abutment against the surface  56  of the latch  5 , this immobilizing this latch in the position of FIG. 3 where it prevents the release of the connector  7  as long as the effort F 3 , generated by the pressure prevailing inside the pipe C 2  and the connector  7 , is greater than a predetermined value which depends on the effort F 1 , i.e. on the stiffness constant of the spring  6 , and this independently of the effort F 2  which may in that case be exerted, or not, on the latch or button  5 .  
         [0041]    In practice, leakages occur at the join between the edge of the opening  82  and the surface  75  and around the skirt  81 , such leakages resulting in a flow E′ of gas under pressure towards the outside of the housing  15 , through the orifice  154 . In this way, the pressure in the pipe C, and in the connector  7  decreases progressively, in the same way as the effort F 3  which may in that case be overcome by the effort F 1  exerted by the spring  6 , this then causing slide of the surfaces  56  and  86  on each other, the return of the piston  8  in the direction of the bottom of the housing  145  and the release of the latch  5  which then attains the position of FIG. 4 where its tooth  55  no longer opposes the withdrawal of the male element B with respect to the female element A.  
         [0042]    The surface  86  is formed by a nose  87  of the piston  8  which may engage in a recess  57  provided to that end on the latch  5 .  
         [0043]    The movements of translation of the piston  8  parallel to axis X-X′ result from the variations in pressure in the conduit  11  of the reaction effort transmitted between the surfaces  56  and  86 , without it being necessary to use a return spring, this improving reliability of the coupler and increasing its economic performances.  
         [0044]    The upstream-convergent nature of the surfaces  56  and  86  allows the piston to return towards the housing  145  under the effect of the effort F 1  when the latter overcomes effort F 3 .  
         [0045]    The inclined surface  56  of the latch  5  has such a slope and orientation that they facilitate the disengagement of the nose  87  borne by the piston  8  during the movement of the latch  5 . Depending on the geometry and inclination of the surfaces  56  and  86 , disengagement occurs more or less easily as a function of the remaining residual pressure, this for the same spring  13 . The coupler  1  may thus be “calibrated” in order that uncoupling is possible from a given residual internal pressure.  
         [0046]    In the second form of embodiment of the invention shown in FIGS.  5  to  7 , the elements similar to those of the first embodiment bear identical references. The female (A) and male (B) elements of this coupler are intended to fit axially in each other and there are provided in the body  1  of the female element A a latch  5  and a piston  8  similar to those of the first embodiment, these members being provided with respective surfaces  56  and  86  for blocking in configuration of purge or communication with the air of the inner volume of the downstream pipe C 2  and of the male connector  7 . A spring  6  exerts on the latch  5  an effort F 2  directed upwardly in FIGS.  5  to  7 .  
         [0047]    An intermediate piece  9  is housed in the principal conduit of the body  1  of the female element and comprises a cylindrical part  91  provided with a flange  92 , this part  91  having substantially the same outer geometry as the front part of the body  7  of the first embodiment. The piece  9  also comprises a part  93  of larger diameter than part  91  and defining a housing for receiving a male connector  7  of the type described in Patent FR-2-724 710.  
         [0048]    Part  93  is provided, on its circumference, with a plurality of housings  95  for receiving balls  100  capable of being engaged in a peripheral groove  76  of the body  7  which they then retain in position in the part  93 . A spring  96  exerts on the piece  9  an effort F 4  directed towards the opening  111  of the conduit  11 .  
         [0049]    Functioning is as follows:  
         [0050]    In the configuration of FIG. 5, the tooth  54  of the latch  5  maintains the piece  9  in configuration of circulation of fluid through the coupler, the effort F 4  exerted by the spring  96  in that case being overcome and the balls  100  then being opposite a cylindrical part with rectilinear generatrix  115  of the conduit  11 , with the result that they are engaged in the groove  76  and retain the connector  7  captive.  
         [0051]    When the coupler is to be unlocked, an effort F 2  is exerted on the latch  5 , which has the effect of disengaging the tooth  54  with respect to the flange  92  which then comes into abutment against the second tooth  55  of the latch  5 . As previously, under the effect of the flow E of the fluid under pressure, the piston  8  is displaced by the effort F 3  in the direction of the latch  5 , to such a point that its surface  86  comes into contact with the corresponding surface  56  of the latch  5 . The effort F 4  due to the spring  96  slightly displaces the piece  9  inside the conduit  11 , the balls  100  remaining engaged in the groove  76  and thus retaining the connector  7  captive.  
         [0052]    When the pressure in the pipe C 2  and in the pieces  7  and  9  has decreased due to the organized leakages represented by the flow E′, the piston  8  releases the latch  5  which moves, under the effect of the effort F 1  due to the spring  6 , towards the position of FIG. 7 where the flange  92  is released from the tooth  55 , this having the effect of allowing the spring  96  to push the piece  9  in the direction of the opening  111  of the conduit  11 . The balls  100  are thus brought opposite an inner radial groove  121  made in the piece  12 , which makes it possible to extract the balls  100  from the groove  76  of the body  7  of the connector B and thus to release this connector.  
         [0053]    According to a variant of the invention (not shown), one sole catch may be provided on the secondary part  14 , while a corresponding single catch is provided on the principal part  12  for catching of the parts constituting the body of the female element.  
         [0054]    According to another variant, likewise not shown, the catch or catches may be provided on a female zone of the secondary part  14 , while the complementary catch or catches are provided on a male zone of the principal part  12 .  
         [0055]    Whatever the form of embodiment in question, the elements constituting the coupler are advantageously made of a metallic material or a plastics material resisting the pressures of the fluid to be conveyed, and chosen as a function of the nature of the fluid.