MODULAR GAS QUICK COUPLING UNIT WITH CARTRIDGE

Technical field

[0001] The invention is directed to the field of gas connectors, more particularly to the field of quick connectors for supplying appliances with gas or vacuum. Background art

[0002] Prior art patent document published US 2014/0026975 A1 discloses a hydraulic connector comprising a male member and a female member. Each of these two members comprises a housing and a male or female cartridge located in the housing. Each cartridge comprises a shutter of the check-valve type, designed for shutting-off the fluid passage in the cartridge when the male and female members are disassembled. This is particularly useful for hydraulic applications where it is desirable to limit as much as possible any hydraulic oil leakage when dissembling a connector. This connector is not particularly adapted for gas applications.

[0003] Prior art patent document published US 2004/0040596 A1 discloses a connector for gas, comprising a male member and a female member. The latter comprises a housing and a shutter of the check-valve type for shutting-off the gas passage in an outward direction when the male member is dissembled. The shutter is generally tubular and is slidable in the housing against a resilient force of a spring. Upon insertion of the male member in the female member, the shutter is moved from a closed position to an open position that enables a flow of gas through the connector. The housing of the female member comprises a sleeve portion with L-shaped recesses that cooperate with corresponding radial pin on the male member, thereby forming a bayonet type coupling. For safety reasons, it can be desirable to replace the elements of such a connector that guarantee the gas tightness, e.g. the gaskets, the shutter and the seat of said shutter. Such an operation is achieved by replacing the connector.

[0004] For certain applications, like in hospitals, gas coupling units are mounted on the wall in order to provide different types of gas for the caregivers, e.g. compressed air for powering medical devices, oxygen dioxide, oxygen, nitrogen dioxide, medical compressed air and/or vacuum. For such coupling units, the elements that provide a gas tight connection have to be replaced at some intervals. This operation can be time consuming in view of the fact that the coupling units have to be disassembled from the wall for accessing these internal elements.

[0005] Gas supply systems for medical gases are subject to different norms, including the British norm BS 5682:2015, the German norm DIN 13260-2, the norm ISO 9170-1 :2008 and the French norm NF S 90-1 16. This list is of course not exhaustive. These different norms have in common that they provide different standards for providing a safe delivery of medical gas. More specifically, these norms provide technical measures for avoiding the connection of a connector plug designed for a specific medical gas with a coupling unit of another gas. To that end, the German norm DIN 13260-2 provides that the connector plug comprises a normalized external surface with a specific profile (circle, square, hexagon...) that can engage only in a corresponding inner surface on the coupling unit. Also the end of the connector plug as well as the outer diameter of the shutter can show different diameters that prevent a proper gas delivery to an unmatched connector plug.

Summary of invention

Technical Problem

[0006] The invention has for technical problem to provide a solution for the maintenance of coupling units, in particular for medical gases. More specifically, the invention has for technical problem to provide a solution for the maintenance of coupling units that is simple, convenient and economic.

Technical solution

[0007] The invention is directed to a cartridge for a gas coupling unit, comprising: a cylindrical body to be mounted in a housing of the coupling unit, said body forming an inner passage for the gas; an elongated shutter slidable in the cylindrical body and cooperating with a seat on said body for closing the gas passage, said shutter comprising a front end to be contacted by a front tubular portion of a plug cooperating with the coupling unit; wherein the elongate shutter is tubular; and the body comprises a front sleeve, said sleeve housing the front end of the shutter and having a cylindrical outer surface.

[0008] Advantageously, the front sleeve shows a constant wall thickness.

[0009] According to a preferred embodiment, the cylindrical outer surface extends over the whole length of the front sleeve.

[0010] According to a preferred embodiment, the body comprises a first inner cylindrical surface with a first diameter and guiding the shutter, and a second inner cylindrical surface with a second diameter, adjacent to the first inner cylindrical surface and located on the front sleeve, said second diameter being larger, preferably by at least 10%, than the first diameter.

[001 1] According to a preferred embodiment, the front sleeve comprises on the second inner cylindrical surface an internal gasket housed in a groove, said gasket being preferably an O-ring.

[0012] According to a preferred embodiment, the front sleeve comprises a front face with surfaces configured for engaging in rotation and/or in translation with a tool for mounting and/or dismounting the cartridge.

[0013] According to a preferred embodiment, the engaging surfaces on the front face of the front sleeve form recesses.

[0014] According to a preferred embodiment, the recesses extend over the whole thickness of the front sleeve.

[0015] According to a preferred embodiment, the recesses are formed on the front face of the front sleeve.

[0016] According to a preferred embodiment, the recesses widen when moving axially towards the shutter.

[0017] According to a preferred embodiment, the body comprises a portion with an outer thread for engaging with a corresponding inner thread of the housing of the coupling unit, said outer thread having an outer diameter that is less than the diameter of the cylindrical outer surface of the front sleeve.

[0018] According to a preferred embodiment, the cartridge comprises an external gasket surrounding the body axially between the front sleeve and the outer thread, said gasket being configured for cooperating in a gas tight fashion with the housing of the coupling unit.

[0019] According to a preferred embodiment, the cartridge comprises a cylindrical cage extending from the back of the body and housing a spring urging the shutter towards the seat so as to close the gas passage.

[0020] According to a preferred embodiment, the cylindrical cage comprises a back wall with a back face that is flat.

[0021] The invention is also directed to a gas coupling unit comprising: a housing with a bore for receiving a gas connector plug; a cartridge mounted in the bore for opening a gas passage through said housing upon insertion of the gas connector plug into said bore; wherein the cartridge is according to the invention.

[0022] According to a preferred embodiment, the housing comprises a gas release passage opening out in the bore at a location such that, when unscrewing the cartridge out of the housing, the external gasket passes over said channel while the outer thread of the cartridge is still engaged with the inner thread of the housing, so that a volume of compressed gas can be released before release of the thread engagement between the cartridge and the housing.

[0023] According to a preferred embodiment, the bore shows a constant diameter from the opening to the gas release passage.

[0024] According to a preferred embodiment, the housing comprises a disk- shaped shutter that is contacted and kept in an open position by the flat back face of the cylindrical cage.

[0025] According to a preferred embodiment, the housing comprises a base with an open cavity, a cylindrical portion mounted on said base and the open cavity and forming the bore that receives the gas connector plug, the gas coupling further comprising a quick coupling assembly mounted on the cylindrical portion for retaining said plug in said bore after insertion. The quick coupling assembly can comprise balls or pins housed in passages or slots in the housing and configured for cooperating with a shoulder portion of the connector plug. These balls and/or pins can be release from engagement with the shoulder portion by means of a push-ring. Alternatively, the quick coupling assembly can comprise a slotted collar on the housing and hook-shaped prongs on the connector plug, where said prongs are configured for axially engaging the slots.

[0026] According to a preferred embodiment, the open cavity of the base extends axially from an opening to a bottom, said base comprising a seat directed towards the bottom for cooperating in a gas tight fashion with the disk- shaped shutter trapped between said seat and said bottom, said seat being crossed by the cylindrical cage of the cartridge.

[0027] The invention can also be directed to the following items:

[0028] 1. A gas coupling unit comprising: a housing with a bore for housing a cartridge and receiving a connector plug, said cartridge opening a gas passage through said housing upon insertion of the gas connector plug into said bore, wherein the housing comprises a base and a mounting ring to be assembled to the base, said ring and said base comprising each coding elements that cooperate with each other for preventing assembly of the mounting ring with a base that has no corresponding coding element.

[0029] 2. A gas coupling unit according to item 1 , wherein the base forms an open cavity and comprises a mounting face around said opening, said face comprises a least one recess, e.g. a blind hole, preferably several recesses, and the mounting ring comprises a face to be mounted on the mounting face of the base, the mounting face of the mounting ring comprising at least one projection, preferably a stud, for engaging with said at least one recess.

[0030] 3. A gas coupling unit according to item 2, wherein the gas coupling unit comprises a generally U-shaped mounting bracket for mounting the base on a wall, said bracket comprising a central opening to surround the mounting face of the base. The U-shaped mounting bracket can comprise wings for mounting on the wall.

[0031] 4. A gas coupling unit according to item 3, wherein the mounting ring comprises at least two mounting holes for receiving mounting screws engaging with the mounting bracket around the mounting face of the base. The two holes can be diametrically opposed. [0032] 5. A gas coupling unit according to item 4, wherein the position of the projection on the mounting ring relative to the mounting holes forms the coding of said ring.

[0033] 6. A gas coupling unit according to any one of items 1 to 5, wherein the base comprises a peripheral surface with a polygonal profile, preferably hexagonal, allowing different orientations relative to the mounting bracket. The mounting bracket advantageously cooperates with two opposed faces of the peripheral surface of the base.

[0034] 7. A gas coupling unit according to any one of items 2 to 5 and according to item 6, wherein the position of the recess or each of the recesses on the base relative to a corresponding orientation of the different orientations of the base forms the coding of said ring.

[0035] 8. A gas coupling unit according to any one of items 1 to 7, wherein the housing of the gas coupling unit comprises a cylindrical portion that can be secured into the mounting ring so as to engage in a gas tight fashion with the base.

[0036] 9. A gas coupling unit according to any one of items 1 to 8, wherein he cylindrical portion comprises a bore that can receive the cartridge.

[0037] 10. A gas coupling unit according to any one of items 1 to 9, wherein the cartridge is according to the invention.

[0038] The features recited in the above items apply also the gas coupling unit of the invention as provided above. Similarly, the features of the gas coupling unit of the invention as provided above apply also the above items.

Advantages of the invention

[0039] The invention is particularly interesting in that the cartridge according to the invention shows a high level of versatility or modularity for the different standards, e.g. different norms like the British, French and German norms for the supply of medical gases. The front sleeve on the body of the cartridge is compatible with different geometries according to different standards while keeping a very simple construction of the body, i.e. of the cylindrical portion of the body that receives the cartridge.

Brief description of the drawings [0040] Figure 1 illustrates a coupling unit for a wall mount, according to the invention.

[0041] Figure 2 is a sectional view of the coupling unit of figure 1.

[0042] Figure 3 is a sectional view of a coupling unit similar to the one of figures 1 and 2 where a connector plug is engaged.

[0043] Figure 4 is a sectional view of the cartridge housed in the coupling unit of figures 1 to 3.

[0044] Figure 5 is a sectional view of another cartridge that can be housed in the coupling unit of figures 1 to 3 or a similar one.

[0045] Figure 6 is a sectional view of still another cartridge that can be housed in the coupling unit of figures 1 to 3, or a similar one.

[0046] Figure 7 comprises two perspective views of the cartridge of figure 6.

[0047] Figure 8 is detailed view of the base and of the mounting ring of the cylindrical portion of the housing of the coupling unit of figures 1 to 3, illustrating coding means for air.

[0048] Figure 9 illustrates the base and the mounting ring of the cylindrical portion of the housing of the coupling unit of figures 1 to 3, similarly to figure 8, however with coding means for oxygen.

Description of an embodiment

[0049] Figure 1 illustrates in a gas coupling unit according to the invention. The coupling unit 2 comprises a housing 4 that is advantageously configured for a wall mount, e.g. by means of the mounting bracket 6. The housing comprises a hole 8 for receiving a connector plug (not represented in figure 1 ). The coupling unit 2 comprises also a quick-coupling assembly 10 for releasing the connector plug. The opening 8 is surrounded by a coding element 12 showing an internal surface with a specific profile, for instance a hexagonal profile, preventing insertion of a connector plug with a coding external surface that does not match. The hole 8 in the housing 4 houses a cartridge 14 that will be detailed in relation with the remaining figures.

[0050] Figure 2 is a sectional view of the coupling unit of figure 1. The housing 4 comprises a cylindrical portion 4.1 and a base 4.2. The base 4.2 comprises a bore that forms a cavity 16 and into which a ring 18 is engaged, for instance by an external thread engaging with an internal thread on the bore. The ring 18 forms a passage 18.1 that receives the cartridge 14. The ring 18 forms also a seat 18.2 that is designed for cooperating with a disk-shaped shutter 20. The cavity 16 at the bottom of the bore of the base 4.2 is in direct connection with an inlet of the coupling unit, for instance with the hose barb illustrated in figure 1.

[0051] The cylindrical portion 4.1 is fastened to the base 4.2 by means of a mounting ring 22. This latter is screwed onto the base 4.2 as is visible in figure 1. More specifically, the cylindrical portion 4.1 sits on a shoulder portion in the bore of the base 4.2, in a gas tight manner by means of a gasket 24. The cylindrical portion 4.1 comprises a cylindrical bore 26 that receives the cartridge 14. It comprises also an internal thread 28 that engages with an external thread on the body 30 of the cartridge 14. The cartridge 14 comprises also a cylindrical cage 32 that extends from the back of the body 30 through the passage 18.1 of the ring 18. The cylindrical cage 32 comprises a back wall 32.1 with a back face that contacts the disk-shaped shutter 20 so as to hold it off the seat 18.2.

[0052] The cartridge 14 comprises an elongated tubular shutter 34 that is slidably housed in the cylindrical body 30. The shutter 34 carries a gasket 34.1 that is pressed against a seat 30.1 on the cylindrical body 30 by virtue of the spring 36. This latter rests on one side on the back wall 32.1 of the cylindrical cage 32 and on the other side on the shutter 34. In the rest position as illustrated in figure 2, the gas passage in the cylindrical body 30 of the cartridge 14 is shut-off by the shutter 34 whereas the passage 18.1 through the ring 18 is open in view of the fact that the cylindrical cage 32 of the cartridge extends through and beyond said passage 18.1 so as to keep the disk-shaped shutter 20 off the seat 18.2.

[0053] The body 30 of the cartridge 14 comprises a front sleeve 30.2 that is intended to receive a connector plug (as will be described in relation with 3). The front sleeve 30.2 can comprise recesses 38 configured for engaging a tool for screwing and/or unscrewing the whole cartridge 14 relative to the body 4. A gasket 40 surrounds the cylindrical body 30 at a shoulder portion between the front sleeve 30.2 and the external thread. The cylindrical portion 4.1 of the housing 4 can comprise at least one gas release passage 41 extending radially through the wall of said portion and positioned so as to form a gas release passage for compressed gas present in the body 4 between the disk-shaped shutter 20 and the gasket 40 when unscrewing the cartridge 14, e.g. for maintenance purposes. More specifically, the at least one release passage 41 is positioned such that, when unscrewing the cartridge from the body 4, the external thread of the cartridge body 30 still engages with the internal thread on the cylindrical portion 4.1 of the housing 4 when the disk-shaped disk 20 rests on the seat 18.2 (so as to close the passage 18.1 ) and the gasket 40 reaches the at least one passage 41 so as to allow the volume of compressed gas in the housing 4 to expand while the cartridge 14 is still engaged with the housing 4. After release of the volume of compressed gas through the vent hole(s) 41 , the cartridge 14 can be further unscrewed until disengagement from the cylindrical portion 4.1 of the body 4.

[0054] Still with reference to figure 2, the open end of the cylindrical portion 4.1 of the housing 4 comprises a least one, preferably two pins 42 engaging in a corresponding slot in the wall of said portion 4.1 for engaging with a shoulder portion of the connector plug (not represented in figure 2). The slots are inclined so as to allow their retraction when inserting the connector plug. The pins 42 can be released from their engagement with the shoulder portion of the connector plug upon exertion of an axial pressing effort on the ring of the quick-coupling assembly 10. Such a mechanism is as such well known from the skilled person and does not need to be further detailed.

[0055] Figure 3 illustrates a coupling unit similar to the one of figure 2 and in accordance with the invention, with a connector plug engaged in said unit. The connector plug 44 can comprise a coding external surface 44.1 intended to engage a corresponding internal surface of the coding element 12. The plug 44 comprises a shoulder portion 44.2 that engages with the pins 42 that retain the plug in engagement with the coupling unit 2. The plug 44 comprises a tubular end portion 44.3 that engages in a gas tight fashion with the front sleeve 30.2 by means of the gasket 30.3 housed in an internal groove of said sleeve. The front end of plug 44 contacts the corresponding front end of the tubular shutter 34 so as to move and keep it in an open position.

[0056] Figures 4 to 7 illustrate different cartridges that can be mounted on the coupling unit 2 of figures 1 to 3.

[0057] Figure 4 illustrates the cartridge 14 visible in figures 2 and 3. As is apparent in figure 4, the front sleeve 30.2 of the body 30 shows a cylindrical outer surface that extends essentially along the whole length of said sleeve. The body 30 comprises a first inner cylindrical surface 30.5 with a first diameter and guiding the shutter 34, and a second inner cylindrical surface 30.6 with a second diameter, adjacent to the first inner cylindrical surface 30.5 and located on the front sleeve 30.2. The second diameter is larger, preferably by at least 10%, than the first diameter. This sleeve 30.2 provides a gas tight connexion with the connector plug (44 in figure 3). Thanks to the cylindrical outer surface of the front sleeve 30.2, the cartridge can be inserted deeply into the bore of the cylindrical portion of the body (4.1 in figures 2 and 3), allowing a retention of the connector plug at the open end of said cylindrical portion, e.g. by means of retention pins (42 in figures 2 and 3).

[0058] The cartridge in figure 4 is according to the DIN norm 13260-2. According to that norm, the outer diameter of the end portion of the connector plug (44.3 in figure 3) is of 10mm for all types of medical gases. According to this norm, each of the inner diameter of the end portion of the connector plug, the outer diameter of the tubular shutter and the outer diameter of the shoulder portion of the connector plug (44.2 in figure 3) can show two different values, so as to provide different combinations for the different types of gas. For instance the inner diameter of the end portion of the connector plug can be of 3.5 or 5.9mm; the outer diameter of the tubular shutter can be of 5.2 or 6.7mm; and the outer diameter of the shoulder portion of the connector plug can be of 12 or 14mm. This means that a cartridge compliant with that norm can show two different outer diameters of the front sleeve, that diameter corresponding to the outer diameter of the shoulder portion of the connector plug. A cartridge compliant with that norm can show can also show two different outer diameters of the tubular shutter.

[0059] Figure 5 illustrates another cartridge that can be mounted in the coupling unit of figures 1 to 3. This cartridge is according to the British norm BS 5682:2015. The reference numbers in figures 2 to 4 are used here for designating the same or corresponding elements, these numbers being however incremented by 100. It is also referred to the description of these elements in relation with figures 2 to 4. As is apparent in figure 5, the front sleeve 130.2 of the body 130 of the cartridge 1 14 is shorter and shows a higher wall thickness.

[0060] The cartridge in figure 5 is according to the British norm BS 5682:2015.

According to that norm, the gas connecting part of the connector plug is identical for all medical gases. The coding is achieved by a sleeve-shaped collar around the gas connecting part, intended to engage in a corresponding circular groove on the coupling unit. With reference to figure 3 showing the coupling unit with a cartridge and a corresponding connector plug according to the DIN norm, the coding collar according to the BS norm would replace the coding external surface 44.1 and the corresponding coding circular groove would be formed in the coding element 12.

[0061] Figure 6 illustrates still another cartridge that can be mounted in a coupling unit similar to the one of figures 1 to 3. This cartridge is according to the French norm NF S 90-1 16. The reference numbers in figures 2 to 4 are used here for designating the same or corresponding elements, these numbers being however incremented by 200. It is also referred to the description of these elements in relation with figures 2 to 4.

[0062] According to the above French norm, the retention of the connector plug in the coupling unit is achieved by hook-shaped prongs (two, three, four or five) that axially engage with corresponding axial slots on a collar on the body of the coupling unit. Once there prongs are axially engaged in the slots and pass beyond said slots, the connector plug is rotated so that the hooks on the prongs are axially retained by the collar. The coding is achieved by a combination of different prong layouts (two, three, four or five) and different diameters of the of the end portion of the connector plug that engage in a gas tight manner with the coupling unit. That end portion shows a constant outer diameter that varies between 6 and 8mm (i.e. takes discrete values of 6mm, 7mm or 8mm).

[0063] As is apparent in figure 6, the wall thickness of the front sleeve 230.2 is larger than in the cartridge of figure 4 for the DIN norm (where the inner diameter of the front sleeve is of 10mm).

[0064] Figure 7 shows two perspective views of the cartridge of figure 6. The shape of the recesses 238 is better visible than in figure 6. Each recess 238 is formed on the front face of the front sleeve and forms a slot that widens when moving axially towards the rear of the cartridge. More specifically, each recess 238 extends radially through the wall of the sleeve 230.2. Each recess 238 forms a T or L-shaped axial profile that allows the insertion of a tool. The tool can comprises an elongate body and at least one, preferably two pins that extends radially from one end of said body so to be able to engage in the recesses 238 upon axial movement of the tool towards the cartridge. Once the pins are engaged in the bottom of the recesses 238, the tool can be rotated so that the pins slide in the recesses 238 and rotatably and axially engage with the cartridge. The cartridge can then be screwed and unscrewed in the body of the coupling unit. The axial engagement of the tool with the cartridge is interesting for it allows to extract the cartridge out of the body by a mere traction on the tool (after having unscrewed said cartridge until disassembly). The above description of the recesses applies to all types of cartridges according to the invention, including those in figures 2 to 5.

[0065] Figures 8 and 9 illustrate the base and the mounting ring of the cylindrical portion of the housing of the coupling unit of figures 1 to 3 with two different coding means for two different types of gas, e.g. air and oxygen.

[0066] Each of figures 8 and 9 illustrate the base 4.2 of the housing, as illustrated in figures 2 and 3. The base 4.2 comprises a peripheral surface 44 with a series of faces, said surface being for instance hexagonal. With reference to figure 1 illustrating the mounting bracket 6, it is apparent that said bracket is U-shaped so as to extend along two opposed faces of the peripheral surface 44 of the base 4.2. This means that the unit 4.2 can be positioned relative to the mounting bracket 6 with different orientations, for instance three orientations with the connecting port 46 oriented upwardly and three orientations with the connecting port 46 oriented downwardly. It is to be understood that other polygonal profiles than a hexagonal one can be considered.

Still with reference to figures 8 and 9, the front face of the 48 of the base 4.2 can comprise coding or indexing holes 50 that are intended to avoid the mounting of a mounting ring 22 that correspond to another type of gas than the one of the base. Figures 8 and 9 illustrate the mounting ring 22 visible in figures 1 to 3, the ring being shown from its rear mounting face

22.1 , i.e. the face intended to contact the front face 48 of the base 4.2. As is apparent the mounting face 22.1 of the mounting ring 22 comprises two opposed ear portion with mounting hole 22.2 intended to receive the mounting screw visible in figure 1 and engaging with the mounting bracket 6. As is still apparent in figures 8 and 9, the mounting ring 22 comprises on its mounting face 22.1 a stud 22.3 intended to engage in one of the holes 50 on the base 4.2. More specifically, in figure 8, the stud 22.3 is offset with regard to a vertical longitudinal axis passing by the mounting holes

22.2. The corresponding holes 50 on the base are each also off-set with regard to a corresponding vertical longitudinal axis of the base when said base is oriented with the hole in an upward position. The base 4.2 and the mounting ring 22 illustrated in figure 8 are for instance for the delivering of air, being however understood that the coding holes 50 and stud 22.3 of figure 8 can be used for another type of gas. Similarly, in figure 9, the stud 22.3 is aligned with the longitudinal vertical axis of the mounting ring 22, said axis passing by the mounting holes 22.2 and the corresponding holes 50 on the base are each aligned with a corresponding vertical longitudinal axis of the base when said base is oriented with the hole in an upward position. The base 4.2 and the mounting ring 22 illustrated in figure 9 are for instance for delivering oxygen, being however understood that this could be other types of gas. This means the mounting ring 22 for oxygen as illustrated in figure 9 cannot be mounted on a base 4.2 for air as illustrated in figure 8. Similarly, the mounting ring 22 for air as illustrated in figure 8 cannot be mounted on a base 4.2 for oxygen as illustrated in figure 9. When mounting such gas delivery installations, the pipes and bases are usually color-coded per type of gas. This allows then a safe and proper mounting of the front portions (cylindrical portion with quick-coupling assembly, and cartridge) of the coupling unit.