Abstract:
The high pressure gas inlet channel ( 6 ) of the pressure regulator ( 1 ) is formed upstream in a stationary valve element ( 7 ) having an enlarged terminal head ( 9 ) interacting with a seat edge of a movable seat ( 10 ) acted upon in closure position by a spring ( 23 ), the mounting of the pressure regulator ( 1 ) in the high pressure gas inlet tap body ( 3 ) causing the retraction of the seat ( 10 ) and the opening of the inlet channel normally kept blanked off during operations of storage and/or washing of the pressure regulator. 
     Applies mainly to sea diving pressure regulators.

Description:
BACKGROUND OF THE INVENTION 
   The present invention concerns pressurized breathable gas pressure regulators, of the type comprising one end connectable to a body of a high pressure gas inlet tap, this end defining a pressurized gas inlet channel, particularly for mixing breathing gas for divers or firefighters/rescuers. 
   These types of pressure regulators are connected and disconnected to/from the tap/gas tank assembly before and after each use. In the field of sea diving, after each use, the pressure regulators are rinsed in fresh water and then stored in free air. 
   To prevent the ingress of foreign bodies (dust, damp, grease, etc) into the pressure regulator during its storage and possible rinsing, a proposal has been made to fit onto the connection end an articulated blanking element, for example of the cover type, that can be actuated manually. This manual actuation not only makes the connection end complex and fragile and prevents the installation of a protective cap, but also makes the connection procedure complex and does not protect against the ingress of foreign bodies just before or after the connection/disconnection with the tap/bottle assembly. 
   SUMMARY OF THE INVENTION 
   The object of the present invention is to propose a simple, robust and reliable arrangement for an automatic blanking off or opening of the gas inlet channel during connection to the tap body and suitable equally for “yoke” type or “DIN” type connections. 
   To do this, according to one feature of the invention, the inlet channel terminates in a stationary valve element interacting with a movable seat acted upon by an elastic means in a position of blanking off the inlet channel and comprising an external face capable of interacting in engagement with a corresponding surface of the tap body to push back the movable seat when coming into contact with the elastic means to an open position during connection with the tap body. 
   According to other features of the invention:
         the movable seat is annular and forms a seat edge interacting with a rear surface, typically frustoconical, of a portion of the terminal head of the valve element   the external face of the movable seat is an annular end face interacting with a shoulder formed in the tap body   the end of the pressure regulator is screwed into or pressed against the tap body by a yoke screw.       

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the invention will emerge from the following description of embodiments, given for information but in no way limiting, made with reference to the appended drawings, in which: 
       FIG. 1  is a schematic view in section of a first embodiment according to the invention for a connection of the “yoke” type; 
       FIG. 2  is an enlarged view in partial section of the whole of  FIG. 1  in a configuration of interconnection with the tap body; 
       FIG. 3  is a schematic view in section before assembly of another embodiment of the invention for a “DIN” type connection; 
       FIG. 4  is a view in perspective of the assembly of  FIG. 3 ; and 
       FIG. 5  is a view in partial section of the assembly in  FIG. 3  in the connected configuration. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   In the following description and in the drawings, identical or similar items bear the same reference numbers, indexed where necessary. 
   The embodiment in  FIGS. 1 and 2  shows a pressure regulator block  1  incorporating an integrated pressure regulator device with membrane  2  intended to be connected to a tap body  3  via, in the “yoke” connection mode, a yoke  4  fixedly attached to the block  1  receiving the tap body  3  and supporting a pressure screw  5  intended to press the tap body  3  in connection position against the pressure regulator block  1 . The latter comprises at least one medium/low pressure gas outlet  60  of the gas fed by the tap body  3  toward the pressure regulator device  2  via a pressurized gas inlet channel  6  leading to the outside of the connection end of the pressure regulator block  1 . 
   As can be better seen in  FIG. 2 , according to one aspect of the invention, the inlet channel  6  is formed, at its entrance, by a blind coaxial bore of a tubular valve element  7  mounted stationary in the connection end of the pressure regulator block  1 , the blind bore  6  leading to the outside via radial passages  8  formed beneath an enlarged terminal head  9  of the element  7 . 
   According to one aspect of the invention, around the stationary valve element  9  is mounted in sliding motion an annular seat  10  having a protruding annular outer end or collar  11  forming an annular end face  12  around the head  9 , the inner recess of the annular collar  11  being connected internally with the sliding bore of the seat  10  on the tubular element  9  by a seat edge  90  normally acted upon in engagement with the rear frustoconical face  13  of the head  9  by a spring  23  resting in the pressure regulator block  1  and pushing the seat  10  outward. 
   In the embodiment shown, the tap body  3  comprises, around the channel  14  letting in the pressurized gas from a pressurized gas container or bottle, a cup of the same transverse dimension as the collar  11  and defining an internal annular shoulder  15  interacting in engagement, when the tap body  3  is pressed by the screw  5  against the pressure regulator block  1 , with the annular end face  12  of the movable seat  10 , thus pushing the latter inward against the spring  14  and opening the passage between the seat edge  90  and the face  13  of the head  9 . The backward movement of the seat  10  in the pressure regulator block  1  is limited by a rear shoulder  91  of the seat butting against a corresponding shoulder of the body  1 . 
   In the embodiment shown, the seal in the connection configuration between the shoulder  15  of the body  3  and the annular end face  12  of the seat  10  is provided by a seal  16  mounted in the bottom of the cup of the tap body  3  and the seal between the movable seat  10  and the stationary valve element  9  is provided by a sliding seal  17  mounted in the seat  10 . The positioning of the seals  16  and  17  between the two pieces may be inverted. 
   The embodiment for the “DIN” type connection shown in  FIGS. 3 to 5  again shows the connection end of the pressure regulator block  1  with its stationary valve element  9  surrounded by the movable seat  10 , acted upon in closed position by the spring  23 , this set here being intended to be entirely received in a hollow cup  18  of the tap body  3  forming, at its bottom, still around the pressurized gas inlet channel  14 , the abutment shoulder  15  and comprising a tapped front end intended to be screwed into the threaded tubular end  19  of the pressure regulator block  1  housing the movable seat  10 . As can be seen in  FIGS. 3 to 5 , the tap body  3  supporting the open/closed tap  20 , is fixedly attached, in this embodiment, to a threaded base  21  intended to be mounted in the neck of a pressurized gas bottle (not shown). 
   As can be seen in  FIG. 5 , when the threaded end  19  of the pressure regulator block  1  is screwed into the cavity  18  of the tap body  3 , the shoulder  15  presses against the annular end face  12  of the movable seat  10  to push the latter back inward, against the spring  23 , and open the passage between the rear contact surface  13  and the seat edge  90 . 
   In the embodiment shown, the seal between the abutment faces  12  and  15  is provided by an O-ring  16  mounted in the movable seat  10  and the sliding motion seal of the latter is provided by a sliding seal  17  interacting here with the peripheral wall of a barrel  22  for mounting the stationary valve element  9  in the pressure regulator block  1 . The assemblies of the seals  16  and  17  may also be inverted. 
   It is evident from the foregoing that, with the arrangement according to the invention, at rest in the storage or washing position, the entrance passage of the inlet channel  6  is hermetically blanked off, the mere connection of the pressure regulator block  1  with the tap body  3  opening this passage to create and maintain a stable determined entrance cross section sufficient to satisfy the breathing performance of a user of the pressure regulated breathing gas, irrespective of the high supply pressure of the latter. 
   In addition, the arrangement according to the invention, with its movable seat, allows the user to rotate the pressure regulator block even in the pressurized connected configuration, users having the annoying habit of forcing the connection of the pressure regulator block to move the medium pressure outlets of the latter into a determined position. The movable seat according to the invention gives a degree of freedom to the connection in the axis of the tap body which prevents the possibility of generating a torque to loosen the pressure regulator block. 
   Although the invention has been described in relation to particular embodiments, it is not limited thereby but is amenable to modifications and variants that will appear to those skilled in the art in the context of the following claims. Thus, in the rest position, the outer end of the movable seat  10  may be covered by a tear-off or removable protective cap.