GB2234307A

GB2234307A - Rotary pipe couplings

Info

Publication number: GB2234307A
Application number: GB9016523A
Authority: GB
Inventors: John Claude Tippett
Original assignee: SWIVELS CONSULTANTS
Current assignee: SWIVELS CONSULTANTS
Priority date: 1989-07-28
Filing date: 1990-07-27
Publication date: 1991-01-30
Also published as: AU5997390A; GB9016523D0

Abstract

A rotary pipe coupling, particularly for use in coupling fire hoses, includes an outer body (2) a rotatable inner spindle (3) and a spigot (4), the body, spindle and spigot having a co-axial bore (5) and the spindle and spigot lying at least partly within the outer body. The spindle and spigot are each provided with engagement means for connection to hoses or conduits. The spigot includes a flange (10) within the housing provided with a fluid seal (12). The outer body includes engagement means preventing complete removal of the spigot and spindle therefrom. <IMAGE>

Description

IMPROVEMENTS IN OR RELATING T@ A COUPLING This invention relates to a coupling and has been devised particularly though not solely for us as a rotating coupling in a conduit or hose such as used by fire brigades.

It is an object of the present invention to provide a coupling which will at least provide the public with a useful choice.

Accordingly the invention consists in a coupling comprising an outer body; an inner rotatable spindle and an end spigot; said outer body, spindle and at least part of said spigot having a substantially co-axial bore therethrough; said inner spindle and spigot each being at least partly positioned in said outer body and each having engagement means whereby said spindle and said spigot may be engaged in use with a conduit or hose; said spigot having an axially extending flange partly positioned inside said inner spindle, a fluid seal between said flange and said spindle; engagement means between said outer body and said spigot to retain said spigot in connection with said outer body and connection means between said inner spindle and said outer body to substantially prevent removal of said inner spindle from said outer body whilst allowing relative rotational movement about the longitudinal axis of said bore.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

One preferred form of the invention will now be described with reference to the accompanying drawings in which Figure 1 is a cross sectional elevation of a coupling according to one preferred form of the invention, and Figure 2 is an end view of the coupling as shown in Figure 1.

In the preferred form of the invention a coupling 1 is provided as follows. The coupling 1 includes an outer body 2, an inner rotating spindle 3 and an end spigot 4. A bore 5 is provided through the coupling by providing bores through the outer body, inner spindle and end spigot and the bore 5 is substantially co-axial in the outer body 2, inner spindle 3 and at least part of the end spigot 4.

As shown in the figure the end spigot 4 has an outlet 6 substantially at right angles to the bore 5 but of course the outlet 6 could be straight through or at a different selected angle. The inner spindle 3 and spigot 4 may be engaged in use with the ends of conduits or hoses and for example threads 7 are provided in the inner spindle 3 and threads 8 are provided in the spigot 4. The recommended direction of flow within said bore 5 being from said spigot 4 to said spindle 3.

The end spigot 4 has an axially extending flange 10 and in the embodiment illustrated the flange 10 is positioned in a rebate 11 in the inner surface of the inner spindle 3 preferably so that the inner surfaces of the flange 10 and spindle 3 lie on substantially the same cylinder. A fluid seal 12 is provided by providing an 'O' - ring, graphite piston rings, polytetrafluoroethylene (PTFE) rings or bronze sealing rings between the inner surface of the inner spindle 3 and the outer surface of the extending flange 10. The fluid seal 12 may be positioned in a rebate 13 in the outer surface of the flange 10 or alternatively in the inner surface of the spindle 3.

Space may be left at 14 to provide a further seal, for example a buffer ring formed for example from TEFLON or a mechanical seal.

So as to spread the load between the outer body 2 and the inner spindle 3 while providing first friction reducing means for relative rotation of the inner spindle 3 about the bore 5 axis, a needle race 20 or carbon bearing can be provided. The first friction reducing means could also comprise a bronze-TEFLON or carbon bushing or a moulded plastic bushing. The needle race 20 may be fitted into a rebate in the outer body 2 and/or the inner spindle 3 and in the embodiment illustrated the needle race 12 is positioned principally in a rebate 21 in the outer body 2.

Between, for example, the end wall of the rebate 21 and the needle race 20 and/or the inner spindle 3, an anti-rubbing an sealing ring (not shown) may be provided if desired.

Connection means are provided to substantially prevent removal of the inner spindle 3 from the outer body 2. To this end in the preferred form an outwardly extending flange 30 is provided on the inner spindle 3 and this may be positioned in a further rebate 31 in the inner surface of the outer body 2. The outer body 2 may be threaded at 32 and a correspondingly threaded lock nut or plug 33 may be provided to engage those threads. An 'O' - ring 34 may be provided to seal the lock nut 33 to the inner spindle 3.

Between the inner edge 40 of the lock nut or plug 33 and the rear face 41 of the flange 30 is provided a thrust bearing or carbon disc 42, the faces of which receive thrust between the inner spindle 3 and the outer body 2 which is substantially parallel to the longitudinal axis of the bore 5. The thrust bearing may also be formed alternatively of a bronze-TEFLON or carbon bushing or a moulded plastic bushing.

An extension shroud 50 (not shown) may be provided to further extend the axially extending flange 10 so that it extends within the spindle 3 across the boundary between the flange 10 and the spindle 3.

In use the shroud 24 may further reduce the pressure on the inner spindle 3 allowing easier rotation of the spindle 3.

The outer body 2 and spigot 4 could be moulded from plastics material while the spindle 3 is formed either from plastics material or metal such as steel.

In use the coupling 1 is engaged in a conduit or hose by connecting a conduit or hose with each of the threads 7 and 8. The outer body 2 and inner spindle 3 are capable of relative movement while being held together by the lock nut or plug 33 which is engaged with threads 32 to prevent the passage of flange 30 past the lock nut 33.. Any tendency for the outer body and inner spindle to twist relative to one another is resisted by the needle race 20 to prevent unwanted locking of the outer body 2 and inner spindle 3 during use.

The provision of the axially extending flange 10 of the spigot 4 reduces, in use, the pressure on the spindle 3 hence allowing easier rotation of the spindle 3 relative to the outer body 2.

The provision of the thrust bearing 22 further aids the rotation of the spindle 3 and outer body 2 and the provision of a thrust bearing either side of the outwardly extending flange 30 will take up expansion between two rigid items coupled through coupling.

Thus it can be seen that a coupling is provided which at least in the preferred form of the invention will allow a rotating coupling to be included in a conduit or hose in a manner such that even under substantially large pressures, locking of the coupling parts one to the other, is substantially prevented As the loading on the seal area is kept down an 'O' - ring of for examples shore 90 grade can be used. Total pressure on the '0' - ring is kept low as the '0' - ring is confined to area little larger than the cross-section of the bore.

It is an advantage of the preferred form that the end spigot nut 4 and/or locking nut or plug 33 may be removed so that each of the parts can be readily removed or assembled should this be required.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A coupling comprising an outer body; an inner rotatable spindle and an end spigot; said outer body, spindle and at least part of said spigot having a substantially co-axial bore therethrough; said inner spindle and spigot each being at least partly positioned in said outer body and each having engagement means whereby said spindle and said spigot may be engaged in use with a conduit or hose; said spigot having an axially extending flange partly positioned inside said inner spindle, a fluid seal between said flange and said spindle; engagement means between said outer body and said spigot to retain said spigot in connection with said outer body and connection means between said inner spindle and said outer body to substantially prevent removal of said inner spindle from said outer body whilst allowing relative rotational movement about the longitudinal axis of said bore.

2. A coupling as claimed in claim 1 wherein said engagement means between said outer body and said spigot are provided by corresponding threads positioned on the inner surface of one end of said outer body and the outer surface of said spigot nut to retain in use said spigot in engagement with said outer body.

3. A coupling as claimed in either claim 1 or claim 2 wherein said coupling includes a first friction reducing means between the outer surface of said spindle and inner surface of said outer body.

4. A coupling as claimed in claim 3 wherein said first friction reducing means comprise a needle race.

5. A coupling as claimed in claim 3, wherein said first friction reducing means comprises a carbon disc or bearing.

6. A coupling as claimed in anyone of the preceding claims wherein said connection means includes a second friction reducing means having faces to receive forces between said outer body and said spindle substantially parallel to said axis of said bore.

7. A coupling as claimed in claim 6 wherein connection means includes a threaded locking nut or plug and corresponding threads said outer body.

8. A coupling as claimed in claim 7 wherein a further seal is provided between said locking nut or plug and said spindle.

9. A coupling as claimed in anyone of claims 6 to 8 wherein said second friction reducing means includes a thrust bearing.

10. A coupling as claimed in anyone of claims 6 to 8 wherein said second friction reducing means comprises a carbon disc or bearing.

11. A coupling as claimed in anyone of the preceding claims wherein said spindle has a rebate therein,, said axially extending flange being positioned in said rebate.

12. A coupling as claimed in anyone of the preceding claims wherein an extension shroud, connected to or extending from said flange, is positioned within the inside surface of said flange and said spindle, so as to extend across the boundary between said flange and said spindle.

13. A coupling substantially as herein described with reference to the accompany drawings.