A SEALING ARRANGEMENT IN A PLUG AND-SOCKET COUPLING WITH A PRESSURE FLUID PASSAGE, PARTICULARLY BETWEEN THE SPOUT OF A LIQUID GAS CONTAINER AND A DISCHARGE REGULATOR MOUNTED THEREON

Abstract: In a plug-and-socket coupling, particularly between a spout (1) of a portable liquid gas container and a regulator (6) mounted thereon, in which a first coupling part (1) has a discharge outlet (5) adapted to receive a stud or protrusion (6) of the second coupling part, leakage to the surroundings from a pressure fluid passage through the coupling is impeded by an annular gasket (16) movably disposed within an annular chamber (15) between the stud (8) and a surrounding skirt (14). Between the gasket and the stud there is a passage for pressure fluid to the annular chamber behind the gasket for loading the gasket to closely abut against the internal surface of the skirt (14) and a surface (17) on the first coupling part.

Description: This invention relates to a sealing arrangement in a plug-and-socket coupling with a pressure fluid passage between the spout of a liquid gas container and a discharge regulator mounted thereon, as defined in the first part of claim 1. In an arrangement of said type known from portable liquid gas containers (GB-A-1214029 the pressure fluid passage of the container spout, i.e. of the first coupling part, discharges through a bore, the diameter of which being only a little larger than the diameter of the protrusion of the second coupling part. In its outer surface the protrusion is provided with a circumferential groove for an O-shaped annular gasket that is supposed to perform sealing about the protrusion in the assembled state of the coupling. In this respect it is a condition that the O-ring fits tightly about the protrusion and it will thus be exposed to a certain wear any time the protrusion is forced into and is pulled clear of the mouth of the container spout. The higher the fluid pressure which the O-ring is to seal against is, the tigther the O-ring must fit about the protrusion, since the pressurized fluid seeks to make its way out to the surroundings through the joint between the annular gasket and the protrusion. US-A-28722221 describes an O-ring movably held within a chamber defined by a housing part and a movable valve element for sealing the space behind the valve element. The sealing arrangement according to the invention is defined by the features of claim 1. In this case the annular gasket may be quite clear of the protrusion of the second coupling part and prior to the eventual assembling of the coupling it may have only a slight pressure against the internal surface of the skirt, thereby almost completely preventing it from being exposed to mechanical wear. This is due to the fact that the sealing effect of the annular gasket after the coupling parts have been joined depends on the circumstance that the pressure fluid leaking out around the protrusion inserted into the mouth will be caught in the annular chamber behind the annular gasket which is thereby loaded to abut firmly against the internal surface of the skirt as well as against the end surface through which the fluid flow passage of the first coupling part discharges. This causes the annular gasket to effectively obstruct the joint indispensable between the skirt and the end surface and which constitutes the only possible leakage way of the pressure fluid. When disassembling the coupling parts the annular gasket will again be relieved of the fluid pressure decisive of the obstructing effect, so that no considerable wear will occur in this phase. The invention will now be explained in more detail by an embodiment with reference to the drawing, in which Fig. 1 illustrates the components relevant in the present context of the discharge spout of a liquid gas container and a discharge regulator while being mounted, but not yet completely tightened up, and Fig. 2 is a part of Fig. 1 on a larger scale and with the components to the left of the illustration in the same situation as in Fig. 1, while the components to the right are shown after the regulator has been fully tightened up. The drawing illustrates the top portion (first coupling part) 1 of a spout supposed to be firmly stuck in a portable liquid gas container not shown, and which in an ordinary way is provided with an external circumferential groove 2 and a channel or flow passage 3 accommodating a self-closing valve with a spindle 4 and which at its top is provided with a narrowed outlet in the form of a bore 5. An associated discharge (second coupling part) regulator 6 which may accommodate a diaphragm-operated reduction valve, not shown, includes an annular collar 7 adapted to be pushed down over the top of the spout 1 and supposed to be provided with locking means, for instance balls or hooks, for engagement with the annular groove 2 of the container spout. Such a locking arrangement is known in various forms and is therefore not shown in the drawing. The regulator or control device 6 includes, moreover, a central stud or protrusion 8 which with a suitably small clearance may be received in bore 5 of spout 1 and which itself has a bore 9 establishing connection between the passage 3 of the spout and a discharge channel 10 with a filter in the regulator 6. In a manner likewise known, the bore 9 accommodates a displaceable valve opener 11 that is spring-biassed in the upward direction and which may be activated by means of an eccentric cam 12 at the end of a pivotally operating shaft 13 which may further be used for tightening up the regulator from the mounting position illustrated in Fig. 1 and to the left in Fig. 2 to the sealed final position in which the components are illustrated to the right in Fig. 2. The regulator 6 has a skirt 14 encircling the stud 8 and defining together therewith a downwardly open annular chamber 15 the radial width of which is somewhat larger than the cross-sectional diameter of an annular gasket 16 illustrated as an O-ring but which may as well have another cross-sectional shape and which in its mounting position abuts slidingly against the internal surface of the skirt 14 the lower edge of which in this position is located at some distance above the top surface 17 of spout 1. The annular gasket 16 is squeezed into the annular chamber 15 through the somewhat narrowed slit between the lower edge of the skirt 14 and a shoulder 18 formed on the stud 8 and against which the gasket is urged by a spring 19 illustrated as a bellows, but which may be of any other type as well. In the mounting position the gasket 16 may thereby be kept clear of the top surface 17 of the spout, against which it gets abutting upon tightening up the regulator 6, see the right side of Fig. 2. Between the annular gasket 16 and the stud 8 a slit 20 is left, see Fig. 2, which after the valve 4 has been opened allows pressure fluid that leaks out through the joint around the end of the stud 8 inserted into the bore, to penetrate into the annular chamber 15 behind the gasket 16, thereby loading said gasket outwardly towards the skirt as well as downwardly towards the top surface 17, so that the indispensable joint 21 between said components is effectively obstructed, thereby preventing pressure fluid from leaking to the surroundings. This also applies in case the skirt is not tightened up to abut firmly against the container spout - as supposed in Fig. 2. Various modifications of the details illustrated in the drawing have already been mentioned above, but other modifications may obviously also be actual. Instead of the self-closing valve 4 a manual valve may for instance be used so that the valve opener 11 becomes superfluous. This will particularly be the case in alternative applications of the sealing arrangement dealt with, e.g. in pneumatic systems or liquid conduits. Moreover, the pressure fluid access past the gasket 16 may be ensured in another way than shown, for instance by grooves in the gasket or in the stud.

Claims: 1. A sealing arrangement in plug-and-socket couplings with a pressure fluid passage, in which a first coupling part (1) accomodates a valve and is connected to a second coupling part (6) which is provided with a protrusion (8) to be inserted into the mouth (5) of the pressure fluid passage (3) of the first coupling part, an annular gasket (16) being provided in the second coupling part to seal the pressure fluid passage against the surroundings, the first coupling part (1) is the spout of a liquid gas container and the second coupling part (6) is a discharge regulator mounted on the spout (1), characterised in that the annular gasket (16) is movably held within an annular chamber (15) provided in the second coupling part (6) between said protrusion (8) and a surrounding skirt (14), said chamber (15) open in the direction towards the first coupling part (1), the annular gasket (16) is in close abutment on the internal surface of said skirt while access for the pressure fluid is provided between the gasket and the protrusion (8) to the annular chamber (15) behind the gasket for pressing the latter to close abutment against said first coupling part (1) around said mouth (5). 2. A sealing arrangement as claimed in Claim 1, in which the annular gasket (16) is spring-biased against the open side of the annular chamber (15) defined between the free edge of the skirt (14) and a shoulder (18) provided on the protrusion (8), said shoulder in the assembled condition of the coupling parts being somewhat displaced into the mouth (5) of the pressure fluid passage (3) of the first coupling part (1).

Inventors: JENSEN, OVE
Applicants: KOSAN TEKNOVA A/S
Application year: 1988
Main classification: F16K21
IPC codes: F17C13