AU717836B2

AU717836B2 - Pipe fitting and method of attaching to a pipe

Info

Publication number: AU717836B2
Application number: AU65542/96A
Authority: AU
Inventors: David Ernest Christie; Ross Ernest Christie; Eric Maxwell Parnham
Original assignee: Dux Eng
Current assignee: Philmac Pty Ltd
Priority date: 1995-09-22
Filing date: 1996-09-10
Publication date: 2000-04-06
Anticipated expiration: 2016-09-10
Also published as: AU6554296A

Description

1 P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 ge*e

ORIGINAL

COMPLETE SPECIFICATION STANDARD

PATENT

Invention Title: "PIPE FITTING AND METHOD OF ATTACHING TO A PIPE" The following statement is a full description of this invention, including the best method of performing it known to the Applicant:el 1A PIPE FITTING AND METHOD OF ATTACHING TO A PIPE This invention relates to a pipe fitting and a method of connecting pipes together.

Polybutylene pipes are now used extensively in plumbing. They are connected together through brass or copper or other metal fittings by swaging a metal collar usually of copper or aluminium on to the end of the pipe connected to the fitting.

The connection is often carried out in confined spaces which makes it a difficult operation for the plumber to ensure the collar, pipe and fitting are joined together in the correct position. There have been a number of proposals to improve the ease of attachment of the pipe to the fitting via a swaging operation and these have been commercially launched with some success. There is still, however, a need for other methods by which the collar can be located in relation to the fitting and the pipe in a manner to simplify the swaging operation in certain circumstances.

It is an object of this invention to provide a fitting and a method of connecting a pipe to that fitting which provides the public with at least an alternative choice to S: 20 the fittings and methods currently available.

In accordance with a first aspect of this invention there is provided a fitting for sealably engaging with the end of a pipe, comprising at least one spigot having a fluid flow path there through, the spigot being adapted to receive the end of a pipe by abutment of the pipe end against a pipe end locating shoulder associated with the or each spigot, each shoulder substantially circumferentially encircling the surface of the spigot, the pipe end being sealable to the spigot using a swaging collar, the fitting further having a collar locating and retaining means substantially adjacent to the pipe end locating shoulder, the swaging collar locating and retaining means being adapted to locate and positively retain a swaging collar in proper relationship to the spigot and the end of the pipe upon rotation of an appropriately adapted collar from a first position where it is not retained to a second position where it is retained.

130BO:NB:#23399.RS I I February 2000 2 In accordance with the invention there is also provided a method of joining a pipe to a fitting comprising, the steps of providing a fitting of the first aspect of this invention, locating a swaging collar on the spigot of the fitting in a manner so that it is positively retained on the fitting, inserting the end of the pipe in the space provided between the swaging collar and the external surface of the spigot, to abut against the pipe end locating shoulder, and then swaging the collar to form a good seal of the pipe to the spigot.

Preferably the collar will be positively retained in a second position on the fitting by rotation of the collar, from a first position, where it is not retained.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a plan view of the fitting of this invention; *so: Figure 2 is an exploded view of the fitting, the swaging

NO..

S"collar and the end of a pipe.

go .o Figure 3 is an exploded view of the fitting and other components of the invention; *0*b Figure 4 is a plan view of the fitting and other components of Figure 3 assembled; Figure 5 is an end view of the swaging collar of the invention.

Referring first to Figure 2, the fitting indicated by arrow 1 has a spigot indicated by arrow 2. A swaging collar indicated by arrow 5 has an internal diameter greater than that of pipe 4. The collar is placed over spigot 2 which then creates an annular space between the collar 5 and the spigot 2 into which the end 3 of pipe 4 can be inserted. When the pipe is forced into that space as far as it can go, the collar 5 is then swaged in known manner compressing the pipe between the collar 5 and the spigot 2.

3 In accordance with the preferred form of the invention the collar is retained on the fitting in the required relationship by inserting the fitting through it and then rotating the collar. A retaining means is provided on the fitting to retain the collar.

The fitting has one or more spigots. In the drawings three are shown but within the scope of the invention it is envisaged that as many spigots as may be required to serve as a connector can be provided. Each spigot is of a hard material, usually brass or copper or other metal, and will usually be formed integrally through a central body portion of the same metal in known manner but can be independently formed and subsequently joined together.

Each spigot will generally have some surface contour to improve the strength of the seal between that surface and the end of the pipe. For example, circumferential ribs 6 can be provided.

5 Associated with each spigot is a shoulder 7 which is present to provide a surface against which the end 3 of the pipe 4 can abut o so as to be located in the optimum position to achieve a good seal upon swaging. To achieve that purpose, the shoulder can be formed in segments and need not be a continuous circumferential surface fully encircling the pipe.

S.

Located immediately adjacent to that shoulder is a means which locates and retains the collar. The means to locate the collar can be a second shoulder 8 stepped back from the first shoulder and locating the collar by the end 9 of the collar 5 abutting

C.

against that shoulder 8. As with the first shoulder 7, the second shoulder 8 need not be a continuous surface but can have sufficient segments to give a sufficient location of the collar.

The collar is retained in relation to that shoulder preferably through a rotating motion of the collar. Means is provided on both the fitting and on the collar itself to achieve this purpose.

In one preferred form, the end of the collar has a number of inwardly depending protruberances. These are indicated as 10, 11, 4 12, 13, 14 and 15. The preferred number of these will become clearer below. A complementary retaining means to these protruberances is provided adjacent to the first shoulder 7 on the fitting. The retaining means shown in the drawings comprises a step 16 between the first and second shoulders, and extending outwardly from that step is an upstanding lug 17 of a shape and construction that one of the protruberances on the end of the collar can be forced behind and be retained in that position. Lug 17 defines a space between its rear surface and the second shoulder 8 into which one protruberance on the collar will engage.

The space has a narrow neck portion leading into a wider cavity.

Each protruberance on the end of the collar is adapted to be forceable through the neck, by finger pressure, into the wider cavity where it will be retained, but in a manner (caused by the shape and size of the components) to allow some limited degree of self-alignment between the collar, the spigot and the pipe. It can be rotated out of that cavity by finger pressure but normally will remain in that position so that then the swaging collar 5 is located in the most appropriate place to perform the swaging e. .2CF: operation when pipe 4 is inserted on the spigot inside the collar.

Generally there will be at least two retaining lugs associated S: with each spigot. The number of protruberances on the collar is not critical. It is feasible to use two protruberance on the end of the collar with two matching lugs on the fitting. Having a number of protruberances 10, 11 etc on the end of the collar makes it easier or quicker for a protruberance to engage with a lug on the fitting. The gap between the protruberances will need to be S sufficient to enable the lugs on the fitting to slide between adjacent protruberances to then allow the rotation of the collar to engage with each lug.

Referring to Figure 3, a further feature of the invention is to provide a protecting means 18 adapted to be inserted into the annular space between the swaging collar 5 and the spigot 6 to protect the open end of the collar 5 against distortion during E packaging and use. Means 18 can have a tubular portion 19 adapted 5 to slide neatly within the swaging collar 5 and have a flange portion 20 at the end which is generally of greater dimension than the end of the collar so that the protecting means 18 can be removed by hand pressure when it is desired to use the fitting to form the seal with the pipe as described above. The flange member can be of any suitable shape such as square and can be used to carry information relating to the fitting. The length of the tubular portion 19 of the protecting means 18 can be such that the end 21 of the spigot will abut against the internal surface of the flange means 20 before the tubular portion 19 of the protecting means is fully forced within the collar 5. This then leaves a gap 22 as shown in Figure 4 when the fitting and protecting means is fully assembled for sale.

Referring to Figure 5 the depths to which the protruberances 11, 12 etc project inwardly within the collar 5 are such that they will freely move over the surface 16 on fitting 1 but engage behind the lug 17.

Alternative means for retaining the protruberances are envisaged such as recesses scored in the step 16 between the two shoulders 7 i: and 8, again of a generally bayonet shape so that each protruberance can be slid along the entry to the recess and then snap into the end part of the recess, to be retained in that position. The end part of the recess can be substantially

'S

perpendicular to the entry portion so that the protruberance can be rotated to snap into the end portion.

**SS

Another possibility is to have an annular recess on the step 16 over which the protruberances can be forced to snap into that recess. That recess could be formed by the step being conical.

The collar 5 and associated protruberances can be that sold under the Registered Trade Mark POSI-RING and which is described and claimed in New Zealand Patent No. 206421 which is herein incorporated by reference.

6 In the method of the invention the collar 5 is connected to the fitting by sliding the collar so that end 9 abuts against shoulder 8. The collar is rotated so that a protruberance, eg. 10 engages behind a lug 17. Pipe 4 is then forced into the annular space between the collar and the spigot until end 3 abuts against shoulder 7. The collar can then be swaged. Swaging will normally occur on that part of the collar away from end 9 so that the protruberances 10, 11 etc, the lug 17 and the step 16 do not interfere with the achievement of a good seal.

As mentioned, each spigot will have associated with it a locating and retaining means for the collar. These can be formed independently in association with each spigot but again for ease of production, the locating and retaining means will be made of a different material than the metal from which the spigots and collar are made. A suitable material is polyethylene which can be moulded in the required shape about the body portion of the fitting. This will generally be done through injection moulding.

*e The attachment of the collar to the fitting need not be tight, there can be some looseness so that the collar is movable side to side in relation to the fitting. This may provide more flexibility and simplify the operation of forcing the end of the tube 4 between the collar and the spigot, giving some degree of self-alignment between the pipe, the collar and the spigot.

.4 ineto hr spoie Therefore in accordance with the invention there is provided a fitting and a method of connecting a pipe to that fitting which in the preferred form offers a simple yet effective positioning of the collar in relation to the fitting to enable the polybutylene pipe 4 to be forced on to the spigot and then the collar swaged.

While this invention has been described with reference to preferred embodiments, it is not to be construed as being limited thereto. Moreover where specific features have been referred to and known equivalents exist therefore, such equivalents are included herein as if specifically set forth.

Claims

1. A fitting for sealably engaging with the end of a pipe, comprising at least one spigot having a fluid flow path there through, the spigot being adapted to receive the end of a pipe by abutment of the pipe end against a pipe end locating shoulder associated with the or each spigot, each shoulder substantially circumferentially encircling the surface of the spigot, the pipe end being sealable to the spigot using a swaging collar, the fitting further having a collar locating and retaining means substantially adjacent to the pipe end locating shoulder, the swaging collar locating and retaining means being adapted to locate and positively retain a swaging collar in proper relationship to the spigot and the end of the pipe upon rotation of an appropriately adapted collar from a first position where it is not retained to a second position where it is retained.

2. A fitting as claimed in claim 1 in which an appropriately adapted collar has a series of inwardly depending protuberances which are adapted to engage with the retaining means upon rotation of the collar into said second position.

3. A fitting as claimed in claim 2 in which an upstanding lug is provided on a 20 step portion adjacent to the pipe end locating shoulder, and so adapted that a protuberance on the collar can be forced behind the lug to be retained thereby.

4. A combination of a fitting as claimed in any one of claims 1 to 3 with an appropriately adapted swaging collar retained on the fitting.

A combination as claimed in claim 4 in which a protecting means is provided for the free end of the swaging collar.

6. A combination as claimed in claim 5 in which the protecting means is a neat fit in the annular space between the swaging collar and the spigot. Lu BOB:NB:#23399.RSI I February 2000 8

7. A fitting for connection with the end of a pipe substantially as herein described with reference to the accompanying drawings.

8. A method of joining a pipe to a fitting comprising the steps of providing a combination as claimed in any of claims 4 to 6, where necessary removing the protecting means, and where necessary locating a swaging collar on the spigot of the fitting and rotating it so that it is positively retained on the fitting, inserting the end of the pipe in the space provided between the swaging collar and the external surface of the spigot to abut against the pipe end locating shoulder and then swaging the collar to form a good seal of the pipe to the spigot.

9. A method of connecting a pipe to a fitting substantially as herein described with reference to the accompanying drawings. DATED: 1 February 2000 CARTER SMITH BEADLE Patent Attorneys for the Applicant: DUX ENGINEERS LIMITED B01:NIB:#23399.RS1 I February 2000