NZ206673A - Pipe joining assembly - Google Patents

Description

V - J v ^ 73 Priority Date(s): .. & ?• ' i Complete Specification Filed: <?/-. iP.: $•? i Class:F.'A . .F/A4-/S/.W. ©3 JM'W.

Publication Date: 1 P.O. Journal, No: .

Patents Form No. 5 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION "IMPROVEMENTS IN CONNECTORS FOR DUCTING" —I",WE WATERMAIN FITTINGS PTY. LTD. a Victorian company of 9-19 Down Street, Collingwood, Victoria, 3066, Australia, hereby declare the invention, for which -t/we pray that a patent may be granted to me-Ais, and the method by which it is to be performed, to be particularly described in and by the following statement © C- 1 . . . • . - V 2066 7 3 The present invention relates, in general, to improvements in fittings suitable for connecting together pipes or tubing. More particularly, but not exclusively, the invention relates to an improved method of and means for providing what may be termed a branch pipe or fitting connection or attachment for systems which are adapted to contain and transmit fluid under pressure.

Nowadays, hydraulic or pneumatic systems are enjoying usage on an ever-increasing scale in a variety of contexts, both household and industrial. In such hydraulic or pneumatic systems the need often arises for the interconnection of two or more lengths of piling or tubing. Many different types of assemblies or fitting connections have in the past been proposed and used • in this particular field. By way of example, and dependent upon practical, spatial and other physical requirements, the interconnection of lengths of tubing may well call for the provision of a tee, an elbow or a joiner in a pipeline. In yet a further alternative it may be necessary merely to provide a cap or end connector means on a single pipe. ^ In the past, assemblies for achieving such results have included a plurality of mutually co-operating elements adapted, in use, to be appropriately positioned around the relevant pipeline or lines and thereafter to be interconnected in any known manner.

However, the prior art connection fittings have in general proven to be somewhat unsatisfactory in a number of respects, as outlined hereunder.

Firstly, and by reason of the number of co-operating .7; parts involved, actual installation could, become a somewhat intricate or complicated procedure, involving perhaps specialised equipment and in certain circumstances the services of a skilled serviceman.. Secondly, the very configuration of the fittings employed has now fceen found to give rise to inefficiencies in use, as for example in sealing, ultimately giving rise to undesirable leakage.

The present invention seeks to overcome the disadvantages associated with the prior art arrangements by providing an improved method of and means for interconnection of piping or tubing, utilizing fewer co-operating parts and encouraging substantially leak-proof sealing.

It should be understood that the arrangement in accordance with the present invention is specifically designed to be compatible with any type of tubing or piping, regardless of the material or construction thereof. In this regard it should be noted that, for a variety of reasons, plastics materials are now enjoying usage on an ever-increasing scale in the construction of piping or tubing for hydraulic or pneumatic systems. However, and whilst the fitting in accordance with the invention is particularly suited for use in interconnection of pipes of plastics material, it is not intended to be so restricted and may be employed for interconnecting pipes of other material, such as for example metal. Throughout the ensuing specification the expression "plastics material" is intended to refer to, for example, rigid or plasticized polyvinylchloride, polyethylene or any other suitable material.

It should furthermore be understood that, whilst 206673 the fitting in accordance with the present invention is primarily intended to be constructed of a metallic material, such as for example gunmetal, brass or perhaps even aluminium, this represents merely a preferred embodiment of the subject invention. Indeed, the fitting could be constructed of any suitable material, as for example a plastics material. there is provided an assembly for substantial fluid-tight connection to a conduit, said assembly including: a first member having a body portion defining a passage for fluid; a second member adapted for location on a conduit and for tightening co-operation with said first member and including a ramp portion; an intermediate member adapted for location around said conduit and to be housed within said second member, said intermediate member including means to cooperate with said ramp portion to cause said intermediate member to move radially inward to grip said conduit as said second member is tightened to said first member and at least one annular rib to define a holding means; and sealing means adapted for housing within said first member and including an end portion retainable in said holding means of said intermediate member whereby said end portion is moved radially inwardly with said intermediate member to maintain said sealing means in sealing contact with said conduit as said second member is tightened to said first member.

In order that the invention may be more clearly understood and put into practical effect, there shall now be described in detail a preferred construction of a conr^etptor In accordance with the present invention, therefore, / 4 assembly for ducting in accordance with the invention. The ensuing description is given by way of non-limitative example only and is with reference to the accompanying drawings, wherein: Fig. 1 is a perspective view cf a connector assembly in accordance with the present invention; Fig. 2 is a perspective view cf the assembly of Fig. 1, with parts or components separated; Fig. 3 is a perspective view of a first embodiment of a grip-ring member in accordance with the invention; Fig. 4 is a perspective view of a further embodiment of a grip-ring member in accordance with the invention; Fig. 5 is a perspective view of yet another embodiment of a grip-ring member in accordance with the invention; Fig. 6 shows an alternative construction for the grip-ring mouber illustrated in Fig. 2; Figs. 7, 8 and 9 are cross-sectional views, taken along the lines 3-3, 4-4 and 5-5, of Figs. 3 to 5 respectively; Figs. 10 to 13 are cross-sectional views (similar to Figs. 7 to 9) of yet further modifications cf a grip-ring member in accordance with the invention; and Fig. 14 is a cross-sectional view of the sealing means cf Fig. 2, taken along the line 13-13 thereon.

In the preferred embodiment illustrated a connector assembly in accordance with the invention is arranged so as to act as what might be termed an end connector for a pipe. It should be understood, however, that the connector assembly in accordance with the invention may be adapted for and is equally applicable to various other types of pipe configuration, as for example elbows, tees and others. The connector assembly illustrated includes an end piece or fitting 1 adapted in use to be secured in any known manner to a first conduit of any known type (not shown). The end piece 1 includes a main body 2 having a longitudinal passage or bore 3 extending substantially centrally therethrough, such a passage or bore 3 opening into a portion 4 of increased diameter adapted, in use, to receive in a substantial push-type fit a second conduit or pipe 5. The main body 2 preferably includes, at one end portion thereof, a male thread 6 adapted for co-operation with a complementary female "thread provided on a clamp member for the aforementioned first conduit. It should be understood, however, that other means may be provided for securing the said first conduit in position relative to the end-piece 1. The main body 2 further includes, at the other end thereof, a threaded portion 7 adapted for co-operation, for example, with a complementary threaded position 8 of a suitable clamping member 9 to be described in more detail hereinafter) designed to assist in retaining the second conduit 5 in a pre-arranged and substantially fixed position relative to the main body 2 (and hence the overall connector assembly).

As stated, in the preferred embodiment there is to be provided a means allowing for interconnection of respective 20667 first and second conduits. In order to allow for such interconnection, in accordance with a preferred feature of the present invention there is provided a fitting or connector assembly including the aforementioned end piece 1, a grip-ring member 10, the so-called clamp member 9, and an appropriate sealing means 11, said sealing means being adapted in use to be disposed within said end piece 1 and intermediate said grip-ring member 10 and said clamping member 9. Preferably, the outermost or free end of the body 2 of the end piece 1 is tapered or chamferred internally, as at 12, whereby to facilitate positioning of the second conduit 5, or alternatively the sealing means 11, therein.

The grip-ring member 10 preferably will take the form of a substantially wedge-shaped member, particular and preferred forms of which are illustrated, for example, in the drawings. The grip-ring member 10 is adapted, in use, to be located within the clamping member 9. Preferably, and as illustrated in Figs. 3 to 5 and 7 to 13, the grip-ring member 10 may include one or more protrusions or teeth 13 adapted, in use, to penetrate the surface of a conduit whereby to retain that grip-ring member 10 substantially fixed relative thereto, whilst at the sane time affording a better seal thereagainst. Alternatively, and as shown for example in Fig. 6, the grip-ring member 10 may include one or more splines 14 located appropriately around the internal dimension thereof, those splines 14 serving substantially the same purpose as the aforementioned teeth 13.

Preferably, and as illustrated, the grip-ring member 10 2066 73 is of a wedge-shape, when viewed in side elevation, and has at least one slot 15 extending longitudinally thereof, whereby to provide a form of split-ring type configuration. The provision of that slot 15 allows for expansion of said grip-ring member 10 whereby to perhaps accommodate different sized conduits. Alternatively, the slot 15 allows for contraction of said grip-ring member 10 whereby to assist in sealing.

In operation the slot 15 of the grip-ring member 10 allows for compression on the insertion thereof, thereby facilitating deposition of that member 10 into the clamping members 9. In this respect it should be noted that the internal configuration of the respective grip-ring member 10 and clamping member 9 are more or less complementary. With such a configuration annular sealing means, for example a ring-shaped member 11, effectively seals off any gap which might have been left between the end piece or fitting 1, the grip-ring member 10 and the clamping member 9. The end piece or fitting 1 preferably includes an annular recess which serves to house such sealing means 11 and prevents that sealing means 11 from being pushed from the end piece or fitting 1 by fluid pressure. In this regard it should be understood that the internal shoulder 16 provided in the main body 2 of end piece or fitting 1 provides a seating for the sealing means 11, and also assists in preventing the sealing means 11 from being ejected by fluid pressure.

The grip-ring member 10, as illustrated for example in the drawings, preferably may be provided with at least one additional tooth 17 on one end face thereof. This additional tooth (or teeth) 17 has been formed, in practice, to serve an important purpose, as will be explained in more detail later in this specification.

The outer exposed surfaces of both the body 2 of fitting 1 and the clamping member 9 are preferably provided with means, a3 illustrated for example at 18 in Figs. 1 and 2, which facilitate gripping thereof by a pipe wrench or the like tool.

The clamping member 9 is provided with the internal threaded portion 8, preferably of buttress form, to threadable engage the thread 7 on the main body 2, and the clamping member 9 preferably terminates at its other end in a tapered section 19 having an inner tapered surface which converges in an outward axial direction. The end terminates in an aperture 20 substantially of a size to accommodate the conduit 5, together with some tolerance to allow for situations wherein the conduit 5 is either non-linear or perhaps has some ovality where it enters the end-piece or fitting 1.

The principle of operation of the connector assembly in accordance with the invention will now be explained in more detail.

Initially the end piece or fitting 1 will be disposed in known manner on the end of a first conduit (not shown). The sealing means 11, gripping member 10 and clamping member 9 are then successively disposed relative to that end piece 1 as illustrated, for example, in Fig. 1. Once thus disposed the complementary male and female threads 7 and 8 on end piece or fitting 1 and clamping member are engaged and the overall assembly is tightened. Once the connector assembly is thus disposed on the first conduit it will be possible, merely as a 6673 result of a pushing action, to insert a second conduit 5 into that assembly. Thereafter, further tightening of the clamping member 9 on the end piece 1, either by manual means or by mechanical means, will result in contraction of the grip-ring member 10 therein and ultimately will cause that grip-ring member 10 to be in a friction or pressure type fit with the second conduit 5. It has been found in practice that, once the second conduit 5, end piece or fitting 1, clamping member 9 etc. are thus interconnected, any attempt to separate the assembly, as for example by attempting to pull the conduit 5 outwardly therefrom, will prove fruitless. In actual fact, experiments have shown that rupture will occur before separation.

The assembly in accordance with the present invention has been found, in use, to be responsible for a number of advantages when compared with the prior art, as explained in more detail hereinafter.

Firstly the teeth (or tooth) 13 provided internally of the grip-ring member 10 will be specifically designed and located so as to assist in keeping the sealing means 11 in a predetermined position relative to the end piece or fitting 1, as by "biting" into the surface of the conduit 5. This has been found to be of importance in ensuring ready location of the second conduit 5 within or relative to the end piece or fitting 1. If the teeth (or tooth) 13 were (or was) not present, there would be a tendency in use for the sealing means 11 to become physically separated from the end piece or fitting 1, and perhaps even eventually 2066 f constitute an obstruction to the passage of the second conduit 5 into that end piece or fitting 1.

The bottom-most tooth 17 provided on the front edge or face of the grip-ring member 10 furthermore serves to act as a barrier against the encroachment of unwanted material between the sealing means 11 and the grip-ring member 10. In this regard it may sometimes happen that the internal teeth (or tooth) 13 of the grip-ring member 10 will exhibit a tendency to cut or shear from the conduit 5 a sliver of material from the surface thereof. Without the tooth or teeth 17 provided on the front edge of the grip-ring member 10, such a sliver would be directed into the space existing between the sealing means 11 and the grip-ring member 10. The front tooth or teeth 17» in effective sealing contact with the sealing means 11, serves to prevent such encroachment of unwanted material.

The uppermost tooth 15 on the front edge of the grip-ring member 10 can be seen, in use, to be in engagement with a ramp 19 provided on the main body 2.

Such interengagement between the tooth 18 and ramp 19■> with the interposition of the sealing means 11 therebetween, serves to retain that sealing means 11 in place and prevents unwanted separation, as by "lifting", of the sealing means 11 from the associated conduit.

The other end or face of the grip-ring member 10 is preferably provided with a tapered or rounded section, designed to assist in the location of the conduit 5 relative thereto and within the end piece or fitting 1. 206673 The split or slot 15 provided in the grip-ring member 10 has been found, in practice, to function to prevent the possibility of overconpression or overcompressive loading on or of the conduit, e.g. a plastics material pipe. In prior art situations or arrangements there has existed the possibility of the imposition of an overcompressive load on the conduit, ultimately resulting in damage to that conduit. The width of the slot 15 in the grip-ring member may be varied to suit different requirements, thereby affording a built-in safety precaution.

The assembly in accordance with the present invention has been found to be particularly effective in situations where conduits are subjected to a pulsating fluid pressure. As the fluid pressure increases it act3 on the relatively large sealed surface area presented by the grip-ring member 10 and associated sealing means 11 to push it (the member 10) back, which in turn increases the gripping effect on the conduit 5- Thus the likelihood of the conduit 5 being ejected through sudden pressure surges is greatly reduced.

The sealing means 11 employed in the arrangement in accordance with the invention, generally in the form of an 0-ring type seal, is preferably constructed of rubber or the like material. However, and especially since nowadays rubber is becoming an increasingly more expensive material, in practical terms the sealing means 11 may "be constructed of any suitable resilient material. It should furthermore be understood that the sealing means 11 need not be circular in cross-section (as illustrated), but may in fact be of or take any suitable shape.

The arrangement in accordance with the present invention exhibits an important practical advantage in terms of the effectiveness of sealing afforded thereby. In this regard it should be noted that, with the prior art arrangements, tightening of the connector means could lead to deformation of the or each associated conduit, ultimately perhaps resulting in a partial "lifting-off" of the sealing means from that conduit, thereby giving rise to undesirable leakage by reason of inadequate sealing. The present applicant's arrangement, by its very configuration, effectively eliminates this possibility of leakage through lifting of the sealing means 11 and separation thereof from the conduit Indeed, the very shape of the grip-ring member 10 of the present applicant's assembly has been found, in use, to ensure continual sealing engagement between the conduit 5 and sealing means 11, regardless of whether or not the conduit 5 is deformed (as for example by overtightening of the clamping member 9). The wedge-shape of the grip-ring member 10 means that, as tightening load on the clamping member 9 increases, contact pressure or load on the conduit 5 via the sealing-means 11 is maintained, if not increased. With the present applicant's arrangement, even if the diameter of the conduit 5 was to be reduced during tightening or tensioning by the clamping member 9» the sealing means 11 has been found always to remain in compression, thereby ensuring proper sealing at all times.

It should be understood that, insofar as the grip-ring member 10 is concerned, the number and location of the teeth 2 0 ^ ^ *j; ■ ;appearing thereon is not essential to the practice of the invention. The number of teeth 15* or alternatively of splines 14, may be varied dependent upon such factors as size (diameter) of piping or conduit, the material of construction of that conduit, etc. The teeth themselves may be of any suitable shape but, in the preferred embodiments illustrated, can be seen to be of a substantially sawtooth shape.

Insofar as the various elements making up the present applicant's connector assembly are concerned, both the sealing means 11 and grip-ring member 10 preferably should be constructed of a suitable resilient material, as for example an elastomer of any known type. The end piece 1 end clamping member 9i on the other hand, should preferably be constructed of a metallic material, as for example brass. In practical terms, however, the end piece 1 and clamping member 9 may be constructed of any material, metallic or otherwise, which exhibit a suiteble strength and/or hardness.

The arrangement in accordance with the present invention exhibits the further practical advantage in that it does not require disassembly of the various components in order to allow for connection to a conduit. Indeed, so long as the clamping member 9 is in a relatively loose condition relative to the remainder of the assembly, a pipe or conduit may be appropriately inserted, the clamping member subsequently tightened, and an effective sealing achieved. This is in marked contrast to the prior art arrangements, which in fact necessitated disassembly in order to allow for location or insertion of a pipe or conduit therein.

It should be understood that, whilst the aforegoing description has referred merely to an assembly for use as an end connector (for connecting together two conduits in an effective straight line), the arrangement in accordance with the invention is equally suited for any other connection situation desired, as for example a tee, an elbow or the like. Indeed, a similar arrangement or assembly, with perhaps minor variations, will be suitable for the connection of any number of conduits in effectively any configuration.

Finally, it is to be understood that the aforegoing description refers merely to preferred embodiments of the present invention, and that variations and modifications are possible without departing from the spirit and scope of the invention. 206673

Claims (12)

WHAT WE CLAIM IS:

1. An assembly for substantial fluid-tight connection to a conduit, said assembly including: a first member having a body portion defining a passage for fluid; a second member adapted for location on a conduit and for tightening co-operation with said first member and including a ramp portion; an intermediate member adapted for location around said conduit and to be housed within said second member, said intermediate member including means to cooperate with said ramp portion to cause said intermediate member to move radially inward to grip said conduit as said second member is tightened to said first member and at least one annular rib to define a holding means; and sealing means adapted for housing within said first member and including an end portion retainable in said holding means of said intermediate member whereby said end portion is moved radially inwardly with said intermediate member to maintain said sealing means in sealing contact with said conduit as said second member is tightened to said first member.

2. An assembly as claimed in claim 1, in which said first member includes a sealing portion adapted for sealing contact with the end portion of said sealing means.

3. An assembly as claimed in claim 2, wherein said sealing portion is provided by a bevelled edge at the inner end of said second member.

4. An assembly as claimed in any preceding claim, wherein said first member includes an internal shoulder defining bore portion of lesser and greater diameter wherein the bore portion of greater diameter provides a housing for 16 J* 'In;206673;said sealing means.;

5. An assembly as claimed in any preceding claim,;wherein said holding means of said intermediate member comprises a pair of annular ribs each having a diameter such that said respective ribs cooperate with an outer and inner edge of said end portion of said sealing means thereby to retain said end portion in said holding means.;

6. An assembly as claimed in any preceding claim wherein said intermediate member is provided by a discontinuous annular member providing a longitudinally aligned gap between a pair of abutment faces of said gap allowing said annular member to be reduced in diameter as said second member is tightened to said first member until said abutment faces come into contact whereby to restrict further tightening thereof.;

7. An assembly as claimed in any preceding claim wherein said intermediate member includes gripping means to retain the conduit in position relative to said intermediate member.;

8. An assembly as claimed in claim 7, wherein said gripping means comprises one or more protrusions extending inwardly from an inner surface of said intermediate member.;

9. An assembly as claimed in claim 7 or claim 8, wherein said intermediate member includes at least one longitudinally extending spline.;

10. An assembly as claimed in any preceding claim, wherein said first and second members are constructed of a metallic material.;

11. An assembly as claimed in any one of claims 1 to 9 wherein said first and second members are constructed ofL;17;206673;plastics material.;

12. An assembly for conduits, substantially as hereinbefore described with reference to the accompanying drawings.;- 18 -;■J;-4 NOV 1986*