Abstract:
Elements for connecting a first end selection ( 3 ) of pipe elements to a second end selection ( 4 ) of pipe elements, the connecting elements including a sealing joint ( 20 ) interposed between the end faces ( 7, 8 ) of the first and second end sections and fixing elements ( 32, 44 ) which are mounted on the first and second end sections and are coupled to first and second axial abutting elements along the first and second end sections in order to hold the above together and compress the sealing joint between them. The first axial abutting elements include an external shoulder ( 9 ) formed on the first section near the end face and the second axial abutting elements include a fixed dowel ( 50 ) provided with elements ( 51 )for axial fixing thereof along the second end section.

Description:
The present invention relates to means for connecting terminal portions of pipe elements end-to-end. 
   BACKGROUND OF THE INVENTION 
   Such connection means are, for example, intended for use in pressurized fluid circuits to connect together two elements of a circuit such as pipes, or to connect a pipe to a functional component that releases or receives fluid. 
   Devices for coupling two pipes are known; they comprise a union piece formed by a tubular body having two ends. One end of each pipe is intended to be introduced into the union piece. The coupling device also comprises two sleeves each screwed onto one end of the tubular body to deform a clamping washer from a position for allowing the pipe to pass freely to a position for retaining the pipe between an inner shoulder of the sleeve and the end of the tubular body. The pipes are generally positioned in the tubular body by means of annular shoulders arranged in the tubular body to form recessed abutments for the pipes in the union. When two pipes of a circuit are connected together and to other elements of the circuit via such coupling devices, removal of one of the pipes, for example to replace it, necessitates being able to separate the two coupling devices from each other after withdrawing the sleeves in order to remove the ends of the pipes from the tubular bodies of those devices. Dismantling in that manner is difficult to accomplish in a relatively complex circuit where some elements may also be fixed on supports. 
   In another embodiment, the connection means comprise a sleeve divided into first and second portions in axial succession provided with means for ensuring removable sealed coupling of those portions respectively at the end of the tubular body and the pipe, and a removable abutment ring provided with means for axially blocking it on the pipe set back from the end thereof to constitute a recessed abutment shoulder for fixing the pipe in the tubular body and an axial abutment shoulder between the second portion of the sleeve and the pipe. One or more sleeves is/are disconnected from the corresponding tubular bodies to uncover the abutment rings and access them to release the pipes on which they are installed. Thus, the pipes can be withdrawn laterally. 
   OBJECTS AND SUMMARY OF THE INVENTION 
   The invention proposes a novel type of connection means providing a simple alternative to existing means, enabling rapid and effective connection of the elements of the circuit to one another, and allowing ready removal of the elements forming the circuit. 
   To this end, the invention provides means for connecting together a first terminal portion of a pipe element and a second terminal portion of a pipe element, the connection means comprising both a seal inserted between end faces of the first and second terminal portions, and fixing means mounted on the first and second terminal portions and associated thereat with first and second axial abutment means along the first and second terminal portions to maintain them close together, compressing the seal between them. The first axial abutment means comprise an outer shoulder formed on the first terminal portion close to the end face thereof and the second axial abutment means comprise a removable bush provided with means for axial blocking thereof along the second terminal portion. 
   In a first embodiment, the first abutment means also comprise a removable bush provided with means for axial blocking thereof along the first terminal portion, and the second abutment means comprise an outer shoulder formed on the second terminal portion close to the end face thereof, the removable bushes being openable to allow them to be engaged laterally on the corresponding terminal portion and being arranged to cooperate with the outer shoulder thereof. 
   In accordance with a first particular characteristic of this embodiment, the fixing means comprise snap fit tabs having one end integral with one of the bushes and an opposing end which extends beyond the end face of the terminal portion on which the bush is arranged and which is arranged to grip the other bush. 
   Thus, the connection is produced by laterally engaging the bushes on the terminal portions then bringing them towards the outer shoulders of said terminal portions to snap fit the bushes onto each other so that the bushes, by cooperating with the outer shoulders of the terminal portions, keep the shoulders close together. 
   In accordance with a second particular characteristic of this embodiment, which may or may not be associated with the preceding characteristic, the outside diameter of the bushes is at least equal to an outside diameter of the outer shoulders of the terminal portions and the fixing means comprise a threaded tubular section and a tapped tubular section each of which is integral with a ring mounted on one of the bushes such that the bushes form axial abutments for the rings, at least one of the threaded and tapped tubular sections extending beyond the end face of the terminal portion on which it is mounted for engagement on the other tubular section when the rings are abutted on the bushes. 
   The connection is then made by stringing the rings onto the terminal portions and then by engaging the bushes laterally on said terminal portions. The rings are then brought back to the bushes which, by cooperating with the outer shoulders of the terminal portions, ensure axial blocking of the rings with respect to said portions. It is thereby possible to produce a strong coupling that is particularly adapted to high pressures. Further, when the connection means are to be used with pipe elements of different diameters, it is advantageous to provide a set of bushes with different inside diameters which correspond to the different outside diameters of pipe elements and which have identical outside diameters so that it is possible to use the same rings with all of the bushes in a set. 
   Preferably, in this embodiment, one of the bushes comprises a portion arranged to extend beyond the end face of the corresponding terminal portion when the bush is abutted against the outer shoulder of said terminal portion and to ensure positioning of the seal facing the terminal face. 
   This holds the seal during assembly by ensuring that it is positioned properly with respect to the terminal portions of the pipe elements, which limits the risk of a leak due to poor assembly of said seal. 
   In a second embodiment, the removable bush is radially deformable and has an outer surface having a tapered portion, the fixing means being integral with the first and second rings mounted respectively on the first and second terminal portions, the first ring having an inner shoulder for cooperation with the outer shoulder of the first terminal portion and the second ring having an internal tapered surface for cooperation with the tapered portion of the removable bush and constituting a means for clamping the removable bush on the second terminal portion. 
   Thus, it is possible to couple a pipe having an end with a shoulder to a pipe that does not have an end with a shoulder. The connection means can thus be used with a plurality of types of pipes, in particular pipes which have been cut to length on site. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     Other characteristics and advantages of the invention become apparent from the following description of particular non limiting embodiments of the invention. 
     Reference is made to the accompanying drawings, in which: 
       FIG. 1  is an elevation of connection means in accordance with a first embodiment of the invention in the connected position; 
       FIG. 2  is a longitudinal cross-sectional half view of said connection means; 
       FIG. 3  is a perspective view of a bush used in said connection means; 
       FIGS. 4 and 5  are perspective views in the disconnected and connected positions respectively of bushes used in a variation of the first embodiment; 
       FIG. 6  is a longitudinal cross-section through connection means in accordance with a second embodiment of the invention, the upper half-view representing the connection means in the connected position and the lower half-view representing the connection means in the disconnected position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIGS. 1 to 3 , connection means in accordance with the first embodiment of the invention are intended to allow end-to-end coupling of two pipes  1 ,  2  each having a terminal portion  3 ,  4  provided with a formed flange  5 ,  6  defining a terminal face  7 ,  8  of the pipe  1 ,  2  on one side and a shoulder  9 ,  10  on the opposing side. 
   The connection means of the first embodiment comprise both sealing means and also means for fixing the pipes to each other. 
   The sealing means comprise a seal  20  which in this case is toroidal in shape. The seal is intended to be disposed between the two terminal faces  7 ,  8  of the pipes  1 ,  2  to be compressed therebetween. The seal  20  has an inside diameter that is substantially equal to the inside diameter of the pipes  1 ,  2  and an outside diameter that is slightly greater than the outside diameter of the formed flanges  5 ,  6 . The seal can have other shapes; for example, instead of a circular cross section, it may have a cross-section that is substantially triangular or trapezoidal, in particular when the formed flanges  5 ,  6  form an angle of less than 90° with the longitudinal axis of the pipe, or it may have a shape that is suitable, when the seal  20  is compressed, for presenting an inner surface interconnecting the inner surfaces of the pipes  1  and  2  without creating a retention zone. The seal  20  may also incorporate an electrically conductive element to ensure electrical conduction between the end faces  7 ,  8  of the pipes  1 ,  2 . This disposition is important in order to prevent a build-up of electrostatic charge. 
   The fixing means comprise a ring with a threaded section, generally designated  30 , and a ring with a tapped section, generally designated  40 , intended for mounting on the terminal portions  3  and  4  respectively via abutment bushes generally designated  50 . 
   The inside diameter of the abutment bushes  50  is substantially equal to the outside diameter of the terminal portions  3 ,  4  and have an end provided with an outer collar  51 . Notches  52  formed by tubular portions extended by axial projections from the collar  51  are disposed thereon about a circle with a diameter that is greater than the outside diameter of the formed flanges  5 ,  6  and close to the outside diameter of the seal  20 . Opposing the notches  52 , the collar  51  defines a shoulder face  53 . The bushes are openable and here each is constituted by two portions  54 ,  55  linked together via a deformable hinge to be able to be engaged laterally on the terminal portion  3 ,  4 . The bushes could also be in two portions linked via an elastic ring to be radially expansible to allow the formed flanges  5 ,  6  to pass through. 
   The threaded section ring  30  has an inside diameter that is substantially equal to the outside diameter of the bush and less than the outside diameter of the collar  51  so that the collar  51  forms an axial abutment for the ring. The threaded section ring  30  is externally divided in an axial direction into a drive section  31  with outer flats, and a threaded section  32  with a thread root diameter that is greater than the outside diameter of the collar  51  of the bush  50 . 
   The tapped section ring  40  is internally divided in an axial direction into a first recess  41  having a diameter that is substantially equal to the outside diameter of the bush  50  connected via an inner shoulder  42  to a second recess  43  having a diameter that is substantially equal to the outside diameter of the collar  51  of the bush  50  and a tapped section  44  the diameter of which corresponds to that of the screw section  32 . 
   The connection is made by stringing the rings  30 ,  40  onto the terminal portions  3 ,  4  then by laterally engaging the open bushes  50  onto the terminal portions  3 ,  4  and closing the bushes  50  over the terminal portions  3 ,  4  of the pipes. The collar  51  of the bushes  50  is brought into a bearing position against the shoulder  9 ,  10  of the formed flanges  5 ,  6 . The notches  52  then extend beyond the end face of the terminal portions. 
   The seal  20  is then placed between the notches  52  of one of the bushes  50  so that the seal  20  is positioned facing the end face  7 ,  8  of the corresponding terminal portion  3 ,  4 . 
   The terminal portions  3 ,  4  of the pipes  1 ,  2  are then approached so that the seal  20  is inserted between the end faces  7 ,  8  of the terminal portions  3 ,  4  and so that the notches  52  of the bushes  50  are inserted between one another. 
   The rings  30 ,  40  are brought over the bushes  50  and brought into abutment with the outer shoulders  53 . It should be noted that the length of the recesses  41 ,  43  is such that the tapped section  44  extends beyond the collar  51  of the bush  50  of the terminal portion  3  so that the threaded section  32  can be screwed into the tapped section  44  until the notches  52  of each bush  50  abut against the collar  51  of the other bush  50 . It should also be noted that the length of the notches  52  is such that the seal is moderately compressed. It should be understood that the bushes  50  held closed by the rings  30 ,  40  axially block the rings  30 ,  40  with respect to the terminal portions  3 ,  4  by cooperating with the outer shoulders  9 ,  10  thereof. 
   When the other terminal portion of the pipe  1  is connected to another element of the circuit via connection means identical to those described, for each end of the pipe  1  the pipe  1  is withdrawn by unscrewing the rings  30 ,  40  then removing the bushes  50  and then by displacing the pipe  1  in a parallel direction thereto. 
   In a variation, as shown in  FIGS. 4 and 5 , each bush  50  comprises two diametrically opposed elastic tabs  56  which extend axially and have one end  57  that is integral with the collar  51  and an opposing end  58  arranged to grip the other bush  50 . Further, portions  54 ,  55  of each bush  50  are provided opposite the hinge with reciprocal snap fit elements  59 . 1 ,  59 . 2  which can maintain said portions  54 ,  55  in the closed position. 
   The bushes  50  engaged on the terminal portions  3 ,  4  are then brought close together, after interposing a seal between the end faces of the terminal portions  3 ,  4 , by inserting the elastic tabs  56  of each bush  50  between the elastic tabs  56  of the other bush  50 . The bushes  50  are then snap fitted with each other. The bushes  50  then alone ensure fixing of the terminal portions  3 ,  4  one to the other. 
   For a stronger fixing, rings identical to rings  30 ,  40  described above can be used in combination with said bushes. Assembly is then identical to that described above. 
   Identical reference numbers to those described above are used to identify elements that are identical or analogous in the following description of a second embodiment of the invention, made with reference to  FIG. 6 . 
   Referring to  FIG. 6 , the connection means of the second embodiment of the invention are intended to allow end-to-end coupling of a pipe  1 , identical to that described above, and a pipe  11  having a terminal portion  12  which is free of any type of shoulder and which has an end face  13 . 
   The connection means of the second embodiment comprise both sealing means and also means for fixing the pipes to each other. 
   The sealing means comprise a seal  60  which comprises an outer tubular section  61  to overlap the terminal portion  12 , an adjacent annular section  62  which projects inwardly of the outer tubular section  61  to cover the end face  13  of the terminal portion  12  and an inner tubular section  63  extending from the annular section  62  facing and at a distance from the external tubular section  61 . The seal  60  comprises a rigid L-shaped reinforcing insert  64  extending within the annular section  62  and the inner tubular section  63 . The seal  60  can also incorporate an electrically conductive element to ensure electrical conduction between the pipes  1 ,  11  to prevent a buildup of electrostatic charges. 
   The fixing means comprise a ring with a threaded section generally designated  70  for mounting directly on the terminal portion  3  and a ring with a tapped section generally designated  80  for mounting on the terminal portion  12  via an abutment bush generally designated  90 . 
   The abutment bush  90  is split so that it is radially deformable. The abutment bush  90  is internally divided in an axial direction into a first recess  91  with an inside diameter that is substantially equal to the outside diameter of the terminal portion  12  and a second recess  92  in which the outer tubular section  63  of the seal  60  is lodged. It should be noted that the outer tubular section  63  of the seal  60  comprises an outer annular step  65  received in a corresponding recess  93  in the second recess  92 . The bush also comprises clips  94  projecting into the first recess  91  and has an outer surface having a tapered portion  95 . The clips  94  are optional. 
   The threaded section ring  70  has an inside diameter that is substantially equal to the outside diameter of the terminal portion  3  and less than the outside diameter of the formed flange  5  so that the formed flange  5  forms an axial abutment for the threaded section ring  70 . The threaded section ring  70  is externally divided in an axial direction into a drive section  71  with outer flats and a threaded section  72  with a thread root diameter that is greater than the outside diameter of the formed flange  5  and the bush  90 . The threaded section ring  70  can be openable to engage it laterally on the terminal portion  3  or to be able to mount it on the terminal portion  3  via an abutment bush  50  as described above. 
   The tapped section ring  80  is internally divided in an axial direction into a first recess  81  with a diameter that is substantially equal to the outside diameter of the terminal portion  12  connected via an inner shoulder  82  to a second recess  83  defined by a tapered surface corresponding to that of the bush  90  and connected to a tapped section  84  the diameter of which corresponds to that of the screw section  72 . 
   The connection is made by engaging the rings  30 ,  40  on the terminal portions  3 ,  12 . The abutment bush  90  and the seal  60  are then strung onto the terminal portion  12 . It should be noted that the tubular sections  61  and  63  diverge slightly to facilitate introducing the terminal portion  12  therebetween. 
   The terminal portions  3 ,  12  of the pipes  1 ,  11  are then brought closer so that the annular portion  62  of the seal  60  is inserted between the end faces  7 ,  13  of the terminal portions  3 ,  12 . 
   The threaded section ring is brought against the formed flange  5  and the tapped section ring  80  is brought onto the abutment bush  90 . The threaded section  72  is engaged in the tapped section  84 . As screw tightening continues, the tapped section ring  80  slides with respect to the bush bearing against the formed flange  5  so that by sliding on the tapered portion  95 , the tapered surface of the recess  83  constitutes clamping means for the bush  90  on the terminal portion  12 , causing the clips  94  to bite into the outer surface of the terminal portion  12 . It should be noted that the length of the portion of the bush  90  projecting from the end face  13  is such that the seal  60  is moderately compressed. The rigid reinforcing insert  65  extending within the annular section  62  and the inner tubular section  63  flattens the inner tubular section  63  against the inner surface of the second terminal portion  12  when the seal  60  is compressed between the terminal portions  1 ,  12 . 
   Clearly, the invention is not limited to the embodiment described, and variations can be made without departing from the scope of the invention as defined in the claims. 
   In particular, the invention can be carried out by inverting the embodiments described. 
   Further, the seal  60  can be annular in shape, in analogy to that of seal  20 .