The present invention relates to a connection assembly and more particularly to a pipe connection assembly for connecting pipes that are capable of carrying fluid (liquid or gas). The pipe connection assembly of the invention may also be used to connect pipes, poles or rods for any other use, for example in the assembly of a pole-supported structure. In particular, the assembly may be used to connect poles for assembling a temporary structure, and in one embodiment the poles have the dual uses of structural support and circulation of fluid, for example carrying hot water for heating or cold water for cooling of the structure. The pipe connection assembly of the invention is also useful for connecting water-carrying pipes in an irrigation system, which may be a temporary or modular irrigation system. Further, the assembly can be used to connect tubes carrying electrical power cables, fibre-optic cables and the like.
There are many methods employed in the art for connecting fluid-carrying pipes such as simple screw thread arrangements, so called “nut and olive” assemblies and “push-grip” methods employing a split collet and using an O-ring to seal.
A nut and olive assembly is an example of a compression type fitting. The fitting comprises an outer compression nut and an inner compression ring which is also known as an “olive”. When the nut is tightened, it clamps down on the olive, causing it to conform to the circumference of the pipe, thereby sealing the joint.
However, once the joint is taken apart, it is possible to remove the pipe from the fitting assembly, but the olive remains permanently squeezed into the pipe. This type of compression fitting is also not especially robust against stresses such as flexing and bending of the pipe. In addition, when assembling the fitting, the olive must be oriented correctly outside the pipe, leading to a relatively complicated fitting process.
A “push-grip” assembly employs a collet which is pushed on to the pipe to be connected and clamps it. For the avoidance of doubt, a standard collet known in the art is a type of chuck that forms a collar around the object to be held (for example a drilling bit, but in the context of this specification, the object is a pipe, rod or tube) and exerts a strong clamping force on the object (pipe, rod or tube) when the collet is tightened via a tapered outer collar.
The push-grip assembly known in the art has an advantage over other connectors, in that it is possible to remove the pipe from its fitting, but to do this it is necessary push the exposed end of a collet in one direction to release the grip of the collet, whilst pulling the pipe in the opposite direction to effect removal. This need for pushing and pulling at the same time is very awkward.
In addition, for larger pipe systems, such as 15 mm or 22 mm water pipes for domestic or irrigation purposes, purely manual action for gripping and releasing the collet is very difficult, whilst for larger pipes, manual action is quite impossible.
Accordingly there is a need in the art for an improved connection assembly. In short, the present invention uses a collet to join a pipe, rod, pole or similar to a connector. The collet of the present invention is provided with an external threaded portion, which is used to drive the closure of the collet required to grip the pipe. That is to say that when the collet is threaded onto an outer, internally threaded holder is and the collet is screwed to the holder, relative movement of a tapered outer portion of the collet along the holder drives the collet together and tightens the grip on the pipe. To relieve the grip the collet is turned in the opposite direction, allowing the collet to open out and so to release the pipe. This avoids the aforementioned problem known in the art, whereby the operator must simultaneously push the collet and pull out the pipe. In the present invention, all that is required is for the operator to unscrew the collet holder and subsequently withdraw the pipe.
The ease of connection and disconnection of pipes that is provided by the present invention makes the inventive assembly ideal for connecting fluid-carrying pipes or tubes, for example water pipes. The invention finds application in carrying hot and cold water for heating and cooling pipe assemblies. The inventive assembly is also useful in connecting water pipes in an irrigation system, which may be a temporary, modular or expandable irrigation system. As the pipes of the irrigation system can easily be interchanged using the assembly of the invention, the irrigation system can easily be extended to irrigate a larger area, or made smaller, by addition or removal of pipes.
The assembly of the invention is also useful in connecting pipes, rods or tubes in the construction of a structure or construction that is supported by pipes, rods, or tubes, for example a tent structure, marquee or solid-wall structure that is nevertheless based on a pole framework. The ease of connection of the poles which is provided by the assembly of the invention means that said structure, which may be a temporary structure, means that the structure can be rapidly assembled and disassembled.
According to the present invention, there is provided a connection assembly for connecting a pipe, rod or pole to a connector, the assembly comprising:
a collet having at a first end thereof a collet head having at least one abutment and at the second end thereof a collet collar, the collet having a bore therethrough, the collet bore being dimensioned and configured to receive and fittingly engage the pipe, rod or pole, the collet head being resiliently deformable so as to impinge on the pipe, rod or pole when deformed inwardly, the collet being provided with at least one screw thread on the external surface of the collet; and
a collet holder having a collet holder bore therethrough, the collet holder bore being dimensioned and configured to receive the collet, the collet holder bore comprising at least one screw thread on the surface thereof which matches the thread of the collet;
wherein in use the collet holder and collet are mutually rotatable about a collet screw thread and a collet holder screw thread to cause relative transverse movement between the collet and collet holder whereby the collet holder impinges on an abutment of the collet head to deform the collet head, thereby impinging on and gripping the pipe, rod or tube.
Preferably, the assembly further comprises:
a collet deflector dimensioned and configured to receive an abutment of the collet;
wherein in use relative transverse movement between the collet and the collet holder causes the collet to engage with the collet deflector, whereby the collet deflector impinges on the abutment of the collet head to deform the collet head, which thereby impinges on and grips the pipe, rod or tube.
According to the present invention, there is also provided a connection assembly for connecting a pipe, rod or pole to a connector, the assembly comprising:
a collet having at a first end thereof a collet head having at least one abutment and at the second end thereof a collet collar, the collet having a bore therethrough, the collet bore being dimensioned and configured to receive and fittingly engage the pipe, rod or pole, the collet head being resiliently deformable so as to impinge on the pipe, rod or pole when deformed inwardly, the collet being provided with at least one screw thread on the external surface of the collet;
a collet holder having a collet holder bore therethrough, the collet holder bore being dimensioned and configured to receive the collet, the collet holder bore comprising at least one screw thread on the surface thereof which matches the thread of the collet; and
a collet deflector dimensioned and configured to receive an abutment of the collet;
wherein in use the collet holder and collet are mutually rotatable about a collet screw thread and a collet holder screw thread to cause the collet to engage with the collet deflector, whereby the collet deflector impinges on an abutment of the collet head to deform the collet head, which thereby impinges on and grips the pipe, rod or tube.
Preferably, the collet deflector is a substantially O-shaped ring having an internal surface that matches, at least in part, an abutment of the collet.
Conveniently, the internal surface of the collet deflector is chamfered.
Advantageously the angle of the chamfer is 40 degrees.
Preferably the connection assembly further comprises a retaining means to retain the collet in the collet holder.
Advantageously the retaining means passes through a radial bore in the collet holder and engages with the collet thereby preventing relative movement between the collet and the collet holder.
Conveniently the retaining means is a pin or screw.
Preferably the collet holder further comprises a gripping portion to allow the collet holder to be manipulated.
Advantageously the collet comprises a gripping portion to allow the collet to be manipulated.
Conveniently the gripping portion or portions comprises spanner flats or a hexagonal section.
Preferably the collet head further comprises an inwardly directed lip for exerting concentrated force on the pipe, rod or tube when the collet head is deformed.
Advantageously the collet holder further comprises engagement means for engaging with the connector.
Conveniently the engagement means comprise a screw thread on an external surface of the collet holder which is dimensioned and configured to engage with a correspondingly dimensioned and configured screw thread provided on the connector.
Alternatively the engagement means comprise at least one barb provided on an external surface of the collet holder, said barb or barbs penetrating the connector or being housed in corresponding recesses in the connector in use.
Alternatively the engagement means comprise a circumferential groove or grooves provided in the collet holder for housing adhesive for adhesive engagement with the connector.
Preferably the assembly further comprises an O-ring for sealing the collet in the connector.
Conveniently the collet holder comprises a circumferential projection in the region of the collet holder to be engaged with the collet head, the circumferential projection being dimensioned and configured to at least partially house the O-ring.
Advantageously the abutment comprises a region of the collet head that has increasing external diameter in the direction from the collet collar at the second end of the collet to the collet head at the first end of the collet.
Preferably the abutment comprises a circumferentially flared portion.
Preferably the abutment comprises a circumferential lip.
Conveniently the collet holder comprises a region that has decreasing internal diameter from the direction of the part of the collet holder to be engaged with the collet head.
Preferably the region having decreasing internal diameter comprises an inwardly flared region.
Advantageously the region having decreasing internal diameter comprises a circumferential step.
The invention also provides a connector for connection to a pipe, rod or tube, the connector comprising a fluid-impermeable body, the body having a bore having a first region of diameter dimensioned and configured to fittingly receive the pipe, rod or tube, the bore having at least one second region of diameter dimensioned and configured to fittingly receive the connection assembly according to the invention.
The invention furthermore provides a kit for connecting a pipe, rod or tube to a connector, the kit comprising at least one connection assembly according to the invention together with at least one connector according to the invention.
Embodiments of the invention are described below with reference to the accompanying drawings in which:
Referring now to
As depicted in
The collet collar 6 is provided with screw thread 7 around the circumference thereof. Whilst in the embodiment shown, just one continuous screw thread 7 is depicted, it would of course be possible to provide a multiple-start thread, or multiple threads.
The head 5 of collet 1 is tapered i.e. flared outward in the direction moving from the thread 7 to the head 5. However, the internal bore 2 of the collet is of substantially similar cross-section throughout, as shown in
As will be described in more detail below, in the depicted embodiment the flared configuration of collet head 5 is used to drive the collet 1 closed. However it is possible that other configurations of collet head could be used; for example, an unflared collet head (such that the entire collet is of substantially identical diameter) could also be employed if provided with some sort of abutment or area of greater diameter to interact with the collet holder 10 described below. For example a circumferential lip; or one or more protrusions provided on collet head 5 would have the desired effect.
In the embodiment pictured in
The assembly of the invention also comprises a collet holder 10 which is depicted in
The collet holder also has a gripping portion 13, which as shown in
The internal bore 11 of the collet holder 10, as shown in
In any event, the dimension of the collet holder 10 is such that it is receivable by the narrowest end of the collet 1, i.e. in the region of the spanner flats 4. Thus the internally threaded 12 holder 10 is to be threaded with the threaded portion 7 of collet 1 by virtue of the mutually threadable screw threads 7 and 12. As the collet 1 is crewed into holder 10, the tapered end 14 of the holder 10 urges against the flared head 5 of collet 1. Due to the provision of slots 3 in the collar 6, said urging forces together the portions of the collar 6 adjacent the slots 3, thereby tending to close up the slots 3. Said forcing together of the head 5 of the collar 3 will cause the head 5 to impinge on a pipe placed within the bore 2 of the collet, thereby tending to clamp the pipe in the collet 1.
Whilst the method of operation has been described above with reference to the collet 1 being screwed onto the collet holder 10, it is to be appreciated that equally the collet holder 10 could be screwed in to the collet 1, which would have the same method of action. In sum, it is the relative movement of the collet holder 10 against the flared head 5 of the collet 1 which causes the head 5 to deform inwardly, thereby gripping a pipe.
The angle of the chamfer of the lip 8 is 30 degrees as depicted. However it is to be appreciated that other angles could be used for the chamfer, being less than 90 degrees but greater than zero degrees, for example 10 to 80, 20 to 60 or 45 degrees.
Turning once more to
Alternatively, as shown in
In yet an alternative embodiment of the invention (not shown) the threaded arrangement of
One advantage of the threaded assembly (
In the embodiment of the invention shown in
The relatively large cross section O-ring 20 has a second function, serving as a compressible thrust member, transferring thrust to urge the collet 1 further into the gripping condition. In order to allow this function, the fit of the collet thread 7 is made to a relative slack fit.
In another embodiment where, perhaps, space, cost, or the choice of O-ring, may be limited, the projection 19 may be absent (see
Turning briefly to describe the connector 16, depicted in
Beyond the sealing point of the assembly, i.e. beyond the O-rings 20 when moving in a direction away from the opening of the bore of the connector 16, there is provided a region of bore 22 which is of substantially identical diameter or of very slightly larger diameter to the pipe to be connected, so as to provide a fit to the pipe. This region 22 is provided to give stability to the pipe once gripped by the assembly 1, 10 and this region should be of a length not less than one third of the pipe diameter. This region is intended primarily as a support for the pipe, but in applications using a plastics pipe such as nylon, the length of pipe protruding from the assembly 1, 10 is advisable to allow the pipe to regain its full diameter after being subjected to the squeezing effect of the collet 1.
Further still away from the opening of the connector bore, there can be provided a region 23 of the connector bore which is narrower in diameter than the pipe. As above, the connector 16 can be a body having a bore and two bore openings. It is therefore to be appreciated that the second bore opening of the connector can be identical to the first bore opening for receiving a second assembly of collet 1 and collet holder 10, so that two pipes can similarly be attached to the connector. This arrangement is suitable for joining identical pipes, and could for example be used also when connecting two poles for framing a temporary building.
Alternatively, the connector 16 could have just one bore opening to receive one collet holder 10 and one collet 1. As described above, the bore has a suitable diameter for receiving the assembly 1, 10, fitting the pipe and possibly having a region of narrower diameter bore. The user can then drill into the connector to provide his or her own second opening to the bore and can provide his or her own attachment to the connector 16 in this way. For example, where the pipe being connected to the assembly by the collet 1 and holder 10 is a water pipe, the user might wish to provide a different type of attachment such as a manifold to the connector 16.
In use, the collet holder 10 can be permanently affixed to the connector 16 using the barbed 18 or adhesive arrangements described above. In use, the collet 1 must therefore be screwed into the collet holder 10. Similarly the connect 16 can be supplied in use screwed onto the screw-type collet holder 10 depicted in
Referring now to
The mode of action of the collet 1, shown in
In
As an additional means of holding the arrangement in place, the connection assembly is provided with a retaining means 28, which in this case is a screw or pin 28. The pin 28 passes through a radial bore in the collet holder 30 so that the end of the pin 28 which has passed through the collet holder 30 becomes located in an aperture between the collet head 5 and the collet screw thread. The pin 28 therefore prevents the collet 1 from falling out of the holder 30 because collet head abutment 5 is prevented from passing the pin 28 due to the enlarged size of the abutment.
The arrangement shown in
However, it is to be appreciated that the connection assembly does not necessarily need to have two identical connectors 30. For example, there could be one collet holder 30 as shown in
The arrangement shown in
The embodiment of
The invention described here also includes a kit for connecting pipes, rods or tubes which comprises at least one collet 1, at least one collet holder 10 together with a connector and preferably an O-ring. The assembly of the invention may be made from any machinable or die cast metal, machinable plastics, or semi-rigid mouldable plastics.
It has been found that the assembly of the present invention grips pipes, tubes or rods very tightly and rigidly. Not only can the assembly be used in simple fluid transfer applications, but the assembly can also be used securely to connect construction pipes, rods or poles in the assembly of unconventional buildings.
When used in this specification and claims, the terms “comprises” and “comprising” and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.
The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilized for realizing the invention in diverse forms thereof.
Number | Date | Country | Kind |
---|---|---|---|
0908123.3 | May 2009 | GB | national |
0913336.4 | Jul 2009 | GB | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/GB2010/050763 | 5/11/2010 | WO | 00 | 3/12/2012 |