Abstract:
A coupling ( 13 ) is used for a fuel cartridge ( 2 ) outlet nozzle ( 1 ) designed to supply a compressed gas mounting device with compressed gas and an intake nozzle ( 3 ) on the device&#39;s intake system ( 4 ). The coupling is a single piece formed to ensure a seal and maintain it between the two nozzles ( 3,1 ) of the cartridge ( 2 ) and the intake system ( 4 ).

Description:
BACKGROUND OF THE INVENTION 
   A compressed gas driven piston nailing or plug-mounting device with a compressed gas supply in the form of a fuel cartridge containing the liquid-state compressed gas in an inner casing. In addition to the fuel the cartridge contains, between the inner and outer casing, a propellant to keep the fuel in a liquid state. A male outlet nozzle is connected to the inner casing and projects through the outer casing. 
   At each firing, a specific dose of compressed gas is injected from the fuel cartridge into a combustion chamber in the mounting device, said quantity being correctly determined only if the compressed gas is in a liquid state. 
   To determine the quantity of compressed gas injected into the combustion chamber, mounting devices often include a solenoid valve with a compressed gas intake nozzle. 
   Known intake systems, such as that described in FR 2 771 796, use a male intake nozzle, inside a socket formed by a peripheral protective skirt. This intake nozzle is designed to cooperate with an outlet valve on the cartridge, removing the valve from its seat to allow the gas to be transferred from the cartridge into the device&#39;s intake system. During the transfer operation, leaks must be prevented around the cartridge valve and the device&#39;s intake nozzle. To this end, often, and in particular in the case of the cartridge described in FR 2 771 796, the cartridge&#39;s outlet valve extends into a male nozzle, which cooperates with the device&#39;s male intake nozzle inside an appropriately outfitted coupling. 
   The coupling contains a gasket extending along both sides of the mating surfaces of both male nozzles and is held inside an adaptor covering inserted into the mounting device&#39;s solenoid valve protective socket as well as a protective socket on the compressed gas cartridge. 
   SUMMARY OF THE INVENTION 
   This invention attempts to overcome this multiplicity of components. 
   To this end, the invention covers a coupling for a compressed gas mounting device fuel cartridge outlet nozzle and an intake nozzle in the device&#39;s gas intake system, designed to prevent leaks between the two nozzles and the means to prevent leaks between the cartridge and the intake system, said coupling consisting of a single piece and shaped to prevent leaks between the cartridge and the intake system. 
   The sealing and holding coupling may include a tubular sealing and holding adaptor around the two nozzles, which may be extended by a ring shaped holding base. 
   The adaptor&#39;s inner wall may be shaped to form a seal between the two nozzles by their lateral walls, with the possibility of an internal recess for containing any leaked gas. 
   The sealing adaptor may also be equipped to provide a seal between the two nozzles with ring-shaped surfaces against the cartridge&#39;s and the intake system&#39;s transverse shoulders. 
   In this case, the adapter may be a smooth adaptor or a bellows-shaped adaptor. 
   The adapter may also seal the ends with o-rings placed in the adapter&#39;s recesses. 
   In another implementation, the coupling is formed to be force mounted between the cartridge and the intake system, with the means for sealing and counter-coupling placed in the cartridge to maintain the seal. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood with the following description of several coupling implementations, referencing the attached drawing, on which: 
       FIG. 1  is a half-cutaway drawing of a first implementation of the coupling; 
       FIG. 2  is a half-cutaway drawing of a second implementation of the coupling; 
       FIG. 3  is a half-cutaway drawing of a third implementation of the coupling; 
       FIG. 4  is a half-cutaway drawing of a fourth implementation of the coupling and 
       FIG. 5  is a half-cutaway drawing of a fifth implementation of the coupling. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referencing  FIG. 1 , the invention coupling, in all its various implementations in all the attached figures, is designed to connect outlet nozzle  1  on liquid-state compressed gas cartridge  2  and intake nozzle  3  on solenoid valve  4  for gas intake on a compressed gas mounting device. Both nozzles are male. 
   Intake nozzle  3  extends inside socket  5  formed by peripheral skirt  6  of solenoid valve  4 . 
   Base  7  of socket  5  defines a ring-shaped “transverse” shoulder  8 . 
   Outlet nozzle  1  extends outside socket  9  formed by peripheral skirt  10  on cartridge  2  and extends upwardly from central contact stud  11  which forms a ring-shaped “transverse” shoulder  12 . 
   Coupling  13 , providing a seal between nozzles  1  and  3 , is a single piece. Its shape allows it to fulfill its sealing function and its holding function between cartridge  2  and solenoid valve  4 . 
   Coupling  13  is made up of tubular sealing and holding adaptor or tubular section  14  and ring-shaped holding base section  15 . 
   Adapter  14  has a straight cylindrical outer lateral surface  16 , on the same axis  17  as the solenoid valve and the cartridge. Adapter  14  further has an irregular inner lateral surface  18 , forming an internal recess  19  for holding leaked gas. Adapter  14  further has two ends  20 ,  21  respectively defining end surfaces  20   a ,  21   a  of adaptor  14 . Holding recess  19  is located between sections  18   a ,  18   b  of inner lateral surface  18  and extends on both sides of the mating surface  55  of both nozzles. When the nozzles are placed end to end, a seal is provided by outer lateral (vertical as shown in  FIG. 1 ) walls  31 ,  33  of the nozzles and sections  18   a ,  18   b  of inner lateral surface  18  (figure). A seal is also provided between end surfaces  20   a ,  21   a  of adaptor  14  and the transverse shoulders  8 ,  12 , respectively. 
   Coupling  13  is thus held between shoulders  8  and  12  by ends  20  and  21  of adaptor  14 . 
   More particularly, the pressures which are exerted (a) by sections  18   a ,  18   b  of the adapter  14  on either side of recess  19  against outer lateral walls  31 ,  33  of the two nozzles, (b) by end surfaces  20   a ,  21   a  at the ends  20 ,  21  of adaptor  14  against shoulders  8  and  12 , and (c) by holding base section  15  against central contract stud  11  and skirt  10 , hold coupling  13  in operating position between the solenoid valve and the cartridge. Holding base section  15  includes central disk  22 . Disk  22  is orthogonal to axis  17 , extended by peripheral skirt  23 , noticeably cylindrical, along axis  17 , and ends in flange  24  placed, with light force, in recess  25  located on the inner wall  26  of skirt  10  of the cartridge. 
   The invention coupling implementations in  FIGS. 2–5  are designed for the same solenoid valve—cartridge set as for  FIG. 1 , therefore it is unnecessary to describe these two elements again or reference them on the figures, except for those that are necessary for describing the structure and operation of the coupling implementations. 
   Coupling  213  in  FIG. 2  is largely similar to that in  FIG. 1 . It is differentiated by inner lateral wall  218  on adapter  214  which is a straight cylinder, as is outer wall  216 , and by adapter  214 &#39;s edges  220  and  221 , which are not ground-down but have recesses  227 ,  228  placed in their transverse ring-shaped surfaces  229 ,  230  for o-rings  231 ,  232  designed to press against shoulders  8  and  12 . With coupling  213 , the seal is provided by the ring-shaped surfaces on ends  229  and  230 . 
   Coupling  313  in  FIG. 3  is distinguished by the fact that it includes only a tubular sealing adaptor  314 , which is smooth, with inner  318  and outer  316  lateral surfaces composed of straight cylinders, without a holding base. Adapter  314  extends around both nozzles  1  and  3  where it is laterally pressed and the two annular surfaces  329 ,  330  press against shoulders  8 ,  12  slightly compressed along the axis. Ring-shaped surfaces  329  and  330  and inner lateral surface  318  provide the seal. Adapter compression is created by the fact that its length at rest is slightly greater than the distance between the free ring-shaped surface of central contact stud  11  on the cartridge, around nozzle  1 , and solenoid valve  4  socket  5  base  7 . 
   Coupling  413  in  FIG. 4  is highly similar to that of  FIG. 3 . It is only distinguished by the structure of the adaptor  414  having inner  418  and outer  416  lateral walls, which are not smooth but bellows-shaped. 
   Coupling  523  in  FIG. 5  includes an undulated sealing and holding adapter  514  with a first edge  533  pressing against shoulder  8  and solenoid valve  4  and, a second opposite edge  534 , against shoulder  12  and cartridge  2 . With an inner rib  535 , close to edge  533 , the adapter presses against the intake nozzle  3  and, with an outer rib  536 , close to edge  534 , it presses against the peripheral skirt  6  of the solenoid valve  4 . In this example, truncated holding skirt  537  extends from an area close to edge  534  between outer rib  536  and edge  534  and ends with curved shoulder  538  forced into recess  25  in cartridge  2 &#39;s skirt  10 &#39;s inner wall. Skirt  537  creates the means of counter pressure, which in recess  9  on the cartridge maintains the seal created by adapter  514 .