FIELD OF THE INVENTION

The present invention relates to a hose coupling and corresponding seal and in one aspect relates to a claw type coupling and seal. BACKGROUND OF THE INVENTION

Hose couplings are used for numerous applications in the transfer of fluids and compressed air. It is important to inhibit the escape of air or fluid at the junction point since any leakage can increase operational costs and pose a safety risk. Claw couplings, including type A (originating from Europe), type B (originating from USA) and Surelok couplings (developed in Australia), have been used for many years within the mining industry. Examples of improvements to these can be seen in specifications AU 716175, AU 713875 and AU 716392 made by the present inventor. Another type of coupling, commonly referred to as "Storz type" couplings, are used in high pressure water hoses, such as those disclosed in US 489,107 to C. Storz, US 4,523,778 to K. Ebert and US 4,886,303 to Carson et al. There are however a number of problems with these existing types of couplings and corresponding seals.

Both the claw and Storz type couplings use two like fittings that can be pushed together and twisted to engage a retaining means, somewhat similar to a bayonet mount. To create an air or fluid seal, two rubber sealing rings are used, one in each fitting, which abut each other when the coupling is joined.

Generally rigid rubber seals have been traditionally used in type A and type B claw couplings, however bellows type seals having a resiliently flexible portion may be used in these couplings as well as in the Surelok couplings. The bellows seals include a toroidal portion that fits into a correspondingly shaped annular cavity in the side of the passageway of the fitting thereby providing a seal between the fitting and air or fluid path. The top of the seal abuts a respective seal in an adjoining fitting - thereby providing a sealed connection between the fittings.

One of the problems with the prior art couplings is that because the seal is position in the side of the passageway it creates turbulence in the flow of fluid or air, which results in inefficiencies in the machinery and therefore higher operational costs. Also the extent to which the seal is exposed to the medium being transported through the coupling can have adverse affects, such as dislodgment of the seal under certain circumstances.

At low air or fluid pressures, below 345 kPa (50 P. S I ), the bellows seals can tend to leak as fluid or gas is able to move behind the lower edge of the seal and out between the edge of the coupling and the seal. This can lead to the creation of dust, mud and other problems which can hinder efficient work practices. This can also lead to increased operation cost and danger to personnel.

In contrast at high pressures, above 2756 kPa (400 P.S.I.), the bellows seals can blow apart. This occurs when the lower edge of the seal folds back upon itself resulting in a portion of the seal blowing out the side of the coupling or the seal otherwise become dislodged within the fluid passageway.

Another limitation with existing seals is that they are positioned within the coupling and extend into the passageway thereby reducing the diameter of the flow path. Some earlier seals reduce the hose's flow path diameter from 50mm down to 32mm. This reduction of the flow path has adverse affects on the delivery of the gas or fluid and increases turbulence within the passageway.

It should be appreciated that any discussion of the prior art throughout the specification is included solely for the purpose of providing a context for the present invention and should in no way be considered as an admission that such prior art was widely known or formed part of the common general knowledge in the field as it existed before the priority date of the application.

SUMMARY OF THE INVENTION

It could be broadly understood that the invention resides in a hose coupling of unitary construction comprising a tail portion, a head, and a passageway passing therethrough, the tail portion configured for connection with a hose, the head being radially enlarged relative to the tail portion, and including an end face perpendicular to said passageway, claws extending outward radially and axially from the head for connection with a like coupling, whereby respective end faces of said hose coupling and like coupling abut, the hose coupling having a seal retaining groove extending inwardly axially of the end face and separated from the passageway by an inner wall, such that in use a seal located in and extending axially outwardly from the seal retaining groove is compressed by contact with an adjacent seal in said like coupling to form a sealed connection.

The tail portion may include ribs, teeth, male or female thread, or any other form of fixing means used on hose couplings for connecting a hose directly or indirectly thereto.

In one form the seal includes an abutment portion protruding axially from the seal retaining groove, and a resiliently deformable portion for retaining the seal in the groove. The resiliently deformable portion acts to anchor the seal within the groove to inhibit displacement therefrom due to the flow of gas or fluid through said passageway.

The extent to which the seal extends into the passageway of the hose coupling thereby constricting the passageway at the head, is less than 30% of the diameter of said passageway, or less than 20%, 10%, 5%, 2% or 1 %. This means that the exposure of the seal to the medium being transported through the coupling is reduced relative to conventional couplings to inhibit the adverse flow affects being produced within the flow path, such as turbulence.

In one form the seal includes an annular elastomeric portion coaxial with a generally rigid ring, the elastomeric portion including an upper abutment portion for abutment with a seal of an adjoining like coupling body the lower resiliently deformable portion being locatable within said annual seal retaining groove, wherein the rigid ring in located adjoining or integral with said abutment portion, whereby the abutment portion is inhibited from deformation in a lateral direction relative the passageway. The generally rigid ring may be constructed from metal, such as stainless steel, plastic or any other suitable rigid material. The rigid ring may have a central opening that is of the same diameter and aligned with an opening extending through the annular elastomeric portion;

The generally rigid ring may be embedded in the upper abutment portion, wherein the rigid ring is positioned within an annular slot, or the elastomeric portion of the seal is formed around the ring. In one form the rigid ring is separated from the upper abutment surface by a 1 mm thick layer of the elastomeric material. The inner boundary of the rigid ring is generally even with an inner boundary of the elastomeric portion to thereby inhibit the formation of turbulence in the flow path.

The respective passageways of the cooperating coupling bodies are preferably axially aligned to reduce the constriction of the passageway.

In one form the deformable portion comprises a depending arcuate leg extending downwardly circumferentially from the abutment portion, the leg being curved outwardly and forming an inwardly open annular chamber, wherein an opening of the chamber is positionable adjacent said inner wall of said hose coupling. \ The inner wall may include apertures extending therethrough whereby an amount of gas or fluid moving along said passageway can enter through said apertures and into said chamber of the resiliently deformable portion.

In another form the deformable portion of the seal may include bifurcated or forked legs, wherein the legs are splayed. The correspondingly shaped groove may include sides that slope inwardly toward the opening of the groove, such that the opening of the groove is narrowed.

The splayed legs may be resiliently flexible whereby they are compressed so they can be inserted through the opening of the groove. Once positioned within the groove the legs return to their original position whereby the legs bear against the inwardly sloping sides of groove to retain the seal in position.

When the cooperating coupling bodies are connected the outwardly extending abutment portion is acted upon by the seal of the opposing coupling body. This forces the seal downward into the groove. As a result the legs of the deformable portion tend to bend thereby providing greater pressure against the.sides of the groove and also upward pressure against the seal of the opposing coupling body.

Alternatively, the seal retaining groove may include generally parallel sides and the deformable portion of the seal may be configured to expand laterally to bear against a side or sides of the groove when it is compressed by the action of an adjoining coupling and corresponding seal. In another form the deformable portion includes a hollow tube portion that is positioned within a correspondingly shaped groove. In use as pressure is applied to the abutment portion of the seal the hollow tube portion is deformed or compressed such that it bears against the sides of said groove. The deformable portion may comprise any configuration that provides a compression means such as a curved leg or legs. Alternatively the groove may be shaped such that the deformable portion is able to move or expand into a recess. Furthermore the deformable portion may be constructed from a ^' material that can be resiliently compressed under pressure. The seal retaining groove may include a shoulder wherein the seal bears against the shoulder to inhibit blow out or displacement of the seal from within the groove.

The deformable portion may include ridges that engage with a side of the groove or channels in a side of the correspondingly shaped groove to inhibit the deformation of the deformable portion.

The deformable portion may further include a plurality of radial ribs that bear against a side of the seal retaining groove. The radial ribs are preferably deformable and extend circumferentially around the outer surface of the deformable portion such that they are compressed against the side of the seal retaining groove when the seal is positioned within the hose coupling.

The deformable portion may be a depending arcuate leg that is curved outwardly and includes a plurality of ribs that extend around the outer surface of the leg at different heights. The end or toe of the depending arcuate leg may be biased inwardly such that when the seal is positioned in the seal retaining groove the end or toe bears against the inner wall of the coupling member and the outer curved side of the seal bears against the opposite side of the correspondingly shaped seal retaining groove thereby forming an enclosed annular chamber.

In still another form the resiliently deformable portion includes a depending leg and toe extending circumferentially around the generally ring shaped seal, the leg and toe forming an inwardly open chamber. The leg and toe are positioned within the correspondingly shaped groove whereby the opening of the chamber is adjacent said inner wall of coupling.

It may be that in the event fluid or gas moves between the inner wall and the inner edge of the seal it is captured within the inwardly open chamber. This would increase the pressure within the chamber thereby further forcing the leg and toe against the sides of the correspondingly shaped groove.

The apertures that extend through the inner wall further permit an amount of gas or fluid moving along said passageway can enter through said apertures and into said chamber of the resiliently deformable portion. This inhibits displacement of the seal out from within the seal retaining groove.

The groove may be formed in the head of the hose coupling. Alternatively the groove or a portion of the groove may be formed by positioning an annular ring within the head of the coupling thereby forming a removable inner wall that is generally coaxially aligned with said passageway. The annular ring may be positioned inwardly of a shoulder in said head of the coupling such that the ring and shoulder cooperate to form the axially extending seal retaining groove.

The annular ring may be constructed from the same material as that of the coupling, so that any wear of the coupling and said ring are generally uniform. The use of a removable ring also means that it can be replaced in the event of abrasion within the passageway caused by the material being transported therethrough.

In accordance with another aspect of the invention there is proposed an annular seal positionable within an outwardly open annular groove in an end face of a hose coupling, said groove being coaxial with a passageway of the hose coupling, the seal having a deformable portion locatable within said groove and a reinforced elastomeric abutment portion extending outwardly from said groove for abutment with a corresponding seal of an attached like coupling, wherein the reinforced abutment portion is inhibited from deformation in a lateral direction relative the passageway.

The seal may be constructed from an artificial elastomer, synthetic rubber copolymer such as, nitrile butadiene rubber, or a natural rubber, wherein the stainless steel ring is embedded into or affixed adjacent the abutment portion of the seal. In one form the seal may reduce contact between the rubber portion of the seal and the flow of air or fluid. The contact surface between the elastomeric portion of the seal and the flow path of the medium through the passageway may be between 0.5mm and 8mm and may be 7mm, 6mm, 5mm, 4mm, 3mm, 2mm or 1 mm for a seal having a radius of 35mm.

The amount of contact between the seal and the flow of air or fluid will depend upon the size of the seal.

This limited contact between the elastomeric portion of the seal and the flow path reduces turbulence and therefore results in generally laminar flow. The seal may also reduce medium hammer within the hose line.

The aforementioned embodiments of the coupling and seal are compatible with other like couplings having conventional seals, including type A and type B coupling and those coupling sold under the Surelok trade mark.

The reinforced abutment portion of said seal may be configured to abut against the end face of a conventional seal or against a reinforced abutment portion of a like seal of an adjoining like coupling.

In this way the coupling and seal combination can be used with both conventional couplings and with a like coupling in accordance with the present invention. The term 'abut' used throughout the specification should be given the meaning of, "to be adjacent to" or "touching ". Accordingly the abutment portions of the adjoining hose couplings may touch or they may oppose each other such that said abutment portions may be separated by a gap of 5mm, 4mm, 3mm, 2mm or 1 mm, depending upon the diameter of the hose coupling. In still another aspect of the invention there is proposed a hose coupling having two cooperating coupling bodies, including

an outwardly open annular groove in an end face of at least one of said cooperating coupling bodies, the groove being coaxial with a passageway of said coupling body and separated therefrom by an inner wall,

an annular seal positionable in said groove and extending outwardly therefrom, the seal having a reinforced abutment portion and a deformable portion located within said groove,

wherein the reinforced abutment portion is inhibited from deformation in a lateral direction relative the passageway, whereby the reinforced abutment portion provides rigidity against lateral pressure from within the hose coupling when the two cooperating coupling bodies are connected.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate implementations of the invention and, together with the description and claims, serve to explain the advantages and principles of the invention In the drawings,

Figure 1 is a perspective view of a pipe coupling illustrating the position of the annular seal retaining groove;

Figure 2 is a side cross-sectional view of the connected cooperating pipe coupling members illustrating the location of respective seals in respective seal retaining grooves;

Figure 3 is a top view of the seal of figure 2;

Figure 4 is a cross-sectional view through A-A of the seal of figure 3;

Figure 5 is a side cross-sectional view of a pipe coupling and seal illustrating the position of the seal in the groove;

Figure 6 is a side cross-sectional view of a second embodiment of the pipe coupling and seal illustrating a correspondingly shaped groove;

Figure 7 is a perspective view of a portion of the seal of figure 4, illustrating the rigid ring;

Figure 8 is a perspective view of a portion of a third embodiment of the seal illustrating the position of the reinforcement ring internal of the elastomeric material; Figure 9 is a side cross-sectional view of a fourth embodiment of a pipe coupling and seal illustrating a correspondingly shaped groove having a shoulder;

Figure 10 is perspective of a fifth embodiment of the seal; Figure 11 is a side view of the seal of figure 10;

Figure 12 is a cross-sectional view of the seal of figure 11 through A-A;

Figure 13 is a side cross-sectional view of the seal of figure 10 retained within a correspondingly shaped groove;

Figure 14 is a side cross-sectional view of two connected pipe coupling

members illustrating a sixth embodiment of the seal being compressed by an opposing like seal;

Figure 15 is a side cross-sectional view of another embodiment of the pipe

coupling member illustrating apertures through which gas or fluid can pass to impinge upon the flexible portion of the seal; and Figure 16 is a seventh embodiment of the seal and corresponding shaped pipe coupling members.

DETAIL PORTIONED DESCRIPTION OF THE ILLUSTRATED AND EXEMPLIFIED EMBODIMENTS

There are numerous specific detail portions set forth in the following description. However, from the disclosure, it will be apparent to those skilled in the art that modifications and/or substitutions may be made without departing from the scope and spirit of the invention. In some circumstance specific detail portions may have been omitted or enlarged so as not to obscure the invention. Similar reference characters indicate corresponding parts throughout the drawings. Turning to the figures for a detailed explanation of the invention, there is illustrated a coupling member 10 demonstrating by way of examples, arrangements in which the principles of the present invention may be employed. As illustrated in figure 1 , in one embodiment the coupling member 10 is a claw type coupling and includes, a head 12 and tail 14 through which passageway 16 passes in a longitudinal direction. The coupling includes an end face 18 around which are positioned hooks 20 and protrusions 22 that are used to form an interference fit between the cooperating coupling bodies or fittings to thereby connect hoses 24, as illustrated in figure 2.

The coupling member 10, also referred to as coupling fittings, are pushed together and twisted so that protrusions 22 engage with and are retained by hooks 20. This action forces the opposing seals 30 held within respective coupling members 10 and 10a together, whereby the flat upper faces of the seals, are substantially perpendicular to the axis of the coupling, and abut when the fittings are joined, as illustrated in figure 2. This abutment makes a fluid or pneumatic seal between the fluid or air path within the fittings and the surrounding environment.

As further illustrated in figure 1 the coupling member 10 includes an outwardly open annular groove 26 in the end face 18. The groove 26 is generally coaxial with the passageway 16 and separated therefrom by an inner wall 28. The groove 26 may be formed in the head 12 or the groove may be formed by the placement of an annular wall member within the coupling that is generally aligned with the

passageway, wherein a space between the outer edge of the annular wall member and a side of the coupling forms the groove. The annular seal 30 is positionable within the groove 26 and extending outwardly therefrom for engagement with a seal 30 of a cooperating coupling member 10a as illustrated in figure 2.

The seal 30 includes a reinforced abutment portion 32 including a stainless steel ring 34 and a deformable portion 36 located within the corresponding groove 26. As illustrated in figure 2 the inner edge 38 of the seal 30 extends only slightly into the passageway 16 to thereby inhibit fluid or air flow disturbance.

As illustrated in figure 2 the respective abutment portions 18 of hose couplings 10 and 10a are separated by a gap. The reader will appreciate that the term 'abut' is to be given the meaning of, "to be adjacent to" or "touching". Therefore the abutment portion of the adjoining hose couplings may touch, or they may oppose each other such that the abutment portions are separated by a gap as shown in figures 2, 14, 15 and 16.

The reinforced seal provides structural rigidity against lateral pressure from the fluid or air within the flow path 40. Accordingly the reinforced abutment portion may be generally non-deformable in a lateral direction relative the flow path 40.

In one embodiment the seal 30 includes an annular elastomeric portion coaxial with a generally rigid ring, the elastomeric portion including an upper abutment portion for abutment with a seal of an adjoining coupling body and a lower deformable portion locatable within the annual groove, wherein the generally rigid ring in located adjoining the abutment portion such that the abutment portion is inhibited from deformation in a lateral direction relative the passageway.

The respective passageways of the cooperating coupling bodies are axially aligned to provide a generally smooth or even flow path.

The deformable portion 36 of the seal 30 illustrated n figures 2 to 5 includes bifurcated or forked legs 42, 44, that are generally splayed. The correspondingly shaped groove 26 includes sides 46 that slope inwardly toward the opening of the groove 26, such that the opening of the groove is narrowed as illustrated in figure 5.

The splayed legs 42, 44 are resiliency flexible whereby they can be compressed so they can be inserted through the opening of the groove 26. Once positioned within the groove 26 the legs 42, 44 return the their original position whereby they bear against the inwardly sloping sides 46 of groove 26 to retain the seal 30 in position.

When the cooperating coupling bodies 10 and 10a are connected, as illustrated in figure 2, the respective outwardly extending abutment portions 32 of the seals are acted upon by the opposing seal. This forces the seals into the respective grooves and as a result the legs 42, 44 of the deformable portion 36 tend to bend thereby providing greater pressure against the sides 46 of the groove 26 and also upward pressure against the opposing seal to thereby provide a tight fluid or pneumatic seal. The annular seal 30 may be constructed from an artificial elastomer, synthetic rubber copolymer such as, nitrile butadiene rubber, or a natural rubber. The stainless steel ring may be embedded into the abutment portion of the seal. The seal 30 can be made by moulding or otherwise forming a suitable elastomer used for the purposes of making seals, e.g. Buna-N Nitrile Duro 57-65, E.P.D.M. and silicone rubbers. The material used will depend upon the specific requirements of the particular application.

The configuration of the seal 30 reduces contact between the rubber portion of the seal and the flow of air or fluid which therefore reduces turbulence and results in generally laminar flow through the coupling. In one form the contact surface of the elastomeric portion of the seal 30 and the flow path is between 0.5-8mm and may be 1 mm or 2mm. The seal may also reduce medium hammer within the line.

In another embodiment, as illustrated in figure 6 the deformable portion includes a hollow tube portion 48 that is positioned within a correspondingly shaped groove 26. In use as pressure is applied by the abutment portion 32 of an adjacent seal 30 the hollow tube portion 48 is deformed or otherwise compressed causing it to bear against the sides of the groove 26.

The reader should however appreciate that the deformable portion 36 may comprise any configuration that provides a compression means such as a curved leg or flange that fits within a correspondingly shaped groove.

The reader will also appreciate that the seal 30 and coupling member 10 of the present invention is compatible with other like couplings having conventional seals, such as type A and type B couplings and the couplings sold under the

Surelock trade mark. The abutment portion 32 and deformable portion 36 in one embodiment are integrally formed with a generally rigid ring being embedded in the abutment portion 32. The rigid ring may be constructed from metal, plastic or any other suitable rigid material. Alternatively the abutment portion 32 and deformable portion 36 are constructed separately and welded or glued together, as illustrated in figure 7. In one embodiment the seal, used for a medium claw coupling having a

50mm hosetail portion, has an overall diameter of the seal is between 60-62mm with the thickness of the deformable portion being between 7-1 mm and the overall height of the seal between 11-15mm. In another embodiment where the seal is used on a small hosetail portion coupling the overall height of the seal is between 10- 11 mm, the overall diameter is around 35mm and the thickness of the deformable portion is around 5mm.

Figure 8 illustrates another embodiment of the seal 30 having the steel ring 34 within the elastomeric portion of the seal, such that the steel ring 34 does not adjoin the flow path of the passageway, but is rather separated therefrom by a section of the elastomeric material. In another embodiment, as illustrated in figure 9, the resiliently deformable portion 36 includes a depending circumferential leg 50 and toe 52 that forms an inwardly open chamber 54. The leg 50 and toe 52 are positioned within the correspondingly shaped groove 26 whereby the opening 56 of the chamber 54 adjacent the inner wall 28 of head 12. The resiliently deformable portion 36 may alternatively include a curved circumferential projection 60 that forms the inwardly open chamber 54 as illustrated in figures 10 to 15. The projection 60 may be arcuate or angular with the groove 26 being correspondingly shaped.

It may be that in the event fluid or gas moves between the inner wall 28 and the inner edge of the seal it is captured within the inwardly open chamber 54. This would increase the pressure within the chamber 54 thereby forcing the leg 50 and toe 52 against the sides of the correspondingly shaped groove 26. Alternatively the leg 50 and toe 52 are configured simply to assist in the location of the deformable portion within the groove 26. The configuration of leg 50 and toe 52 may assist in the insertion of the seal into the groove 26.

As illustrated in figure 9 the head 12 may include a shoulder 58 adjacent the groove 26. The seal 30 is shaped so that when engaged in the groove 26 a portion of the seal bears against the shoulder 58. This configuration assists in capturing the seal in the groove 26 to inhibit blow out or displacement thereof. The groove 26 may also be shaped such that the deformable portion is able to move or expand into a recess, or the deformable portion may be constructed from a materia! that can be resiliently compressed under pressure. Furthermore the deformable portion may include ridges that engage with channels in the side of the correspondingly shaped groove 26 in the head 12 to inhibit the deformation of the deformable portion. In still another embodiment, as illustrated in figures 10 to 13, the deformable portion 36 includes a circumferential projection 60 that is curved outwardly and includes a plurality of radial ribs 62 that extend around the outer surface of the projection 60 at different heights. In the present embodiment five radial ribs 62 extend circumferentially around the outer surface of the projection 60. The radial ribs 62 are deformable such that they are compressed against the side of the seal retaining groove 26 when the seal is positioned within the coupling member 10 as illustrated in figure 13.

The free end 64 of the circumferential leg 60 is biased slightly inwardly, as indicated by broken line 66 in figure 12. This means that when the seal is positioned in the seal retaining groove 26, as shown in figure 13, the end 64 bears against the inner wall 28 of the coupling member 10 and the outer curved side 68 of the seal 30 bears against the opposite side of the correspondingly shaped seal retaining groove 26 thereby forming an enclosed annular chamber 54.

The generally rigid ring 34 is embedded in the upper abutment portion 34, wherein the rigid ring is positioned within an annular slot, or the elastomeric portion of the seal is formed around the ring. In the present embodiment the rigid ring 34 is separated from the upper abutment surface by a 1mm thick layer 70 of the elastomeric material.

The reader should appreciate that the position and configuration of the steel ring insert 34 may vary without departing from the scope of the invention. The steel ring may be contained within the rubber material of the reinforced abutment portion 32 or may extend outwardly therefrom. As further illustrated in the figures the inner edge of the steel ring insert may be uniform with the inner edge of the rubber material.

Figure 14 illustrates the cooperating coupling 10 and 10a with respective seals 30 connected together. As illustrated in the figure the respective resiliently deformable portions 36 of the seals 30, in the present embodiment being

circumferential projections 60 are compressed as the abutment portions 32 of the seals 30 bear against each other. This causes the outer curved side 68 of the seal to bear against the sides 46 of the respective grooves 26. The compression of the resiliently deformable portion 36 within the groove assists to inhibit displacement of the seal therefrom. The resiliently deformable portion 36 acts as an anchor to located the seal 30 in position.

In still another embodiment, as illustrated in figure 15, the inner wall 28 may include apertures 72 extending therethrough whereby an amount of gas or fluid moving along the flow path 40 can enter through the apertures 72 and into the chamber 54 of the resiliently deformable portion 36. This further forces the outer curved side 68 of the seal against the sides 46 of the respective grooves 26 to inhibit displacement. Fluid and gas may also pass through opening 74 between the top 76 of wall 28 and therethrough into the chamber 54 to increase the pressure with the chamber 54 relative the ambient pressure surrounding the coupling 10.

In yet another embodiment, as illustrated in figure 16 the seal may comprise a resiliently deformable portion 36 and an abutment portion 78. The resiliently deformable portion 36 being positionable within the seal retaining groove 26 and configured to act as an anchor to prevent the displacement of the seal 30. The resiliently deformable portion 36 of the present embodiment has a partial generally circular cross-sectional profile and extends circumferentially around and extending outwardly coaxially from the abutment portion 78. The resiliently deformable portion 36 and abutment portion 78 may be of unitary construction or may be affixed together to form the annular seal 30. The seal retaining groove 26 is correspondingly shaped to retain the seal 30 therein.

The illustrated invention provides a coupling that has benefits over the prior art. The invention provides a reinforced seal that is inhibited from becoming dislodged during use. Furthermore the seal reduces the formation of vortices within the flow path. The reinforced abutment portion is also configured to abut against either the end face of a conventional seal or against a reinforced abutment portion of a seal of the present invention. In this way the coupling and seal combination can be used with both conventional coupling of a like configuration and with the coupling of the present invention. This means that existing stocks of coupling can be used without having to replace all the components.

Various features of the invention have been particularly shown and described in connection with the exemplified embodiments of the invention, however, it must be understood that these particular arrangements merely illustrate and that the invention is not limited thereto. Accordingly the invention can include various modifications, which fall within the spirit and scope of the invention. It should be further understood that for the purpose of the specification the word "comprise" or "comprising" means "including but not limited to".