A plumbing connector

Abstract

A pipe connector comprising a hollow body 1. A collet 3 is axially fixed to the body to form a cavity for the pipe. A locking cap 4 screws onto the collet to cause inward deflection of the collet onto

Description

The present disclosure relates to a plumbing connector for use with a plastic pipe. More specifically, it relates to a connector particularly suitable for use with multi-layered pipe (MLCP) for heating hot / cold water systems. However, it may be used for other types of pipe. In particular, the present disclosure relates to developments to the connector disclosed in our own earlier WO 2022 / 018412, WO 2022 / 018413 and PCT / GB2023 / 053124. These applications disclose a connector which can be used in commercial plumbing applications to replace conventional press-fit and push-fit connectors. These applications contain a more detailed discussion of the background art and the problems addressed, and their disclosure is incorporated by reference. WO 2011 / 099519 discloses a metal connector for connecting with a braided hose. EP0206582 discloses an example of a well-known plastic hose connector. This prior art has fundamentally different requirements from those of WO 2022 / 018412, WO 2022 / 018413, PCT / GB2023 / 053124 and the present disclosure in that they are designed to seal with pipes which are highly deformable and therefore can achieve good sealing and gripping by deflecting the material of the hose itself. The present disclosure relates to a number of modifications which have been made particularly to enhance the reliability of operation of the connectors of WO 2022 / 018412, WO 2022 / 018413 and PCT / GB2023 / 053124. According to a first aspect of the present disclosure, there is provided a pipe connector comprising a hollow body having a central throughway defining an axis, the body comprising a tubular part at at least one end, the tubular part having an outer face to seal, in use, with an inner diameter of a pipe placed over the tubular part; a collet fitted over the tubular part of the body so as to be axially fixed with respect to the body and being spaced from the tubular part to form a cavity for the pipe, the inner face of the collet being configured to grip the pipe, in use, and the outer face of the collet having a first screw thread; a locking cap having an inner face with a second screw thread which is complementary to the first screw thread, wherein screwing the locking cap onto the collet from an unlocked configuration to a locked configuration causes inward deflection of the collet to press, in use, the collet onto the pipe and the pipe onto the tubular part to seal the interface between the body and the pipe; wherein the collet has at least one axially extending through slot extending proximally from its distal end to divide the distal end of the collet into a plurality of segments: and; a first location feature at a mid-portion of at least one segment to engage with a complementary second location feature on the body to prevent relative rotation of the collet and body. Providing the location feature which prevents rotation between the collet and the body at a midportion of the at least one segment, rather than doing this using the through slots reduces any torsional deflection of the collet. As a result, radial deformation of the collet in the vicinity of the ring is significantly reduced or eliminated. This reduces the stresses and deformation on the collet. The first location feature may be a projection but is optionally a groove. The first location feature may be on an external face of the collet, but is optionally on an internal face of the collet. The first location feature may be axially spaced from the distal end of the collet but is optionally at a distal end of the collet. The connector may have a means to generate an audible signal as disclosed in the above prior art. A ring is optionally non-rotatably retained with respect to the collet, and saw tooth shaped protrusions are arranged around an inwardly facing surface of the locking cap, the protrusions being positioned to engage with complementary flexible tabs on the ring when the locking cap reaches a fully locked position such that relative rotation of the cap with respect to the body causes the saw tooth shaped projections to repeatedly deflect the tabs radially inwardly to generate an audible noise. This provides an improved acoustic output as the repeated inward deflection of the tabs which then snap outwards once they pass over an individual saw teeth is an efficient way to generate the acoustic signal. The reduced stress caused by the location features helps to ensure that the ring is free to vibrate to provide an audible indication of the locked position of the cap on the collet. The ring may be a close fit on the collet. Optionally the inner diameter of the ring is larger than the outer diameter of the part of the collet that it is retained on in an unstressed state. The spacing between the ring and collet assisted by the reduced deformation of the collet under torsional stress helps enhance the generation of the acoustic signal, as compared to a ring which is effectively damped by contact with the collet The flexible tabs may be arranged in a circumferential sense but are optionally angled at a complementary angle to ramp faces of the saw tooth shaped protrusions. This promotes face to face initial contact between the protrusions and a ramp face of a respective saw tooth shape projection to avoid potential snagging between the protrusions and saw tooth shape projections. A pair of O rings are optionally provided on the outer face of the tubular part to seal, in use, with the pipe. This provides redundancy in the event that one of the seals is damaged or dislodged. According to a second aspect of the disclosure there is provided a pipe connector comprising: a hollow body having a central throughway defining an axis, the body comprising a tubular part at at least one end, the tubular part having an outer face to seal, in use, with an inner diameter of a pipe placed over the tubular part: a collet fitted over the tubular part of the body so as to be axially fixed with respect to the body and being spaced from the tubular part to form a cavity for the pipe, the inner face of the collet being configured to grip the pipe, in use, and the outer face of the collet having a first screw thread; a locking cap having an inner face with a second screw thread which is complementary to the first screw thread, wherein screwing the locking cap onto the collet from an unlocked configuration to a locked configuration causes inward deflection of the collet to press, in use, the collet onto the pipe and the pipe onto the tubular part to seal the interface between the body and the pipe; wherein a ring is non-rotatably retained with respect to the collet, and saw tooth shaped protrusions are arranged around an inwardly facing surface of the locking cap, the protrusions being positioned to engage with complementary flexible tabs on the ring when the locking cap reaches a fully locked position such that relative rotation of the cap with respect to the body causes the saw tooth shaped projections to repeatedly deflect the tabs radially inwardly to generate an audible noise. This provides an improved acoustic output as the repeated inward deflection of the tabs which then snap outwards once they pass over an individual saw teeth is an efficient way to generate the acoustic signal. The optional features of the first aspect of the disclosure may apply equally to the second aspect. An example of a pipe connector in accordance with the presence disclosure will now be described with reference to the accompanying drawings, in which: Figure 1A is a side view of a connector and two pipes with the connector in its unlocked configuration and prior to insertion of the pipe; Figure 1B is a view similar to Figure 1A with the pipes inserted into the connector; Figure 1C is a view similar to Figures 1A and 1B in the locked configuration; Figures 2A to 2C are views which are similar to Figures 1A to 1C in part cross-sectional form showing internal features of the collet and pipe; Figures 3A to 3C are perspective views of the connector and pipes corresponding to Figures 1A to 1C; Figure 4A is a perspective view of the connector with one end in an unlocked configuration and the other end shown in an exploded configuration; Figure 4B is view similar to Figure 4A with the other end shown in an unlocked configuration and the one end shown in an exploded configuration; Figure 5 is a cross-section of the connector in the position shown in Figure 1B with the two pipes inserted and in the unlocked configuration; Figure 5A shows the detail in the rectangle A in Figure 5; Figure 6 is a view corresponding to Figure 5 with the connector in the locked position; Figure 6A shows the detail of rectangle A in Figure 6; Figure 7 is a view corresponding to Fig 1C; Figure 7A is a cross section through line A-A in Figure 7; Figure 7B shows the detail in circle B in Figure 7A. Figure 8 is a perspective view of a cap; and Figure 9 is a perspective view of a ring. The plumbing connector described below shows a double-ended axial connector in which both ends are configured according to the present disclosure. The connector may be applied to other shapes such as a single end, a right-angled or T connector. Further, the connector may be provided at only one end and the opposite end may have a different type of connection or be integrated into some other component such as a valve or other fitting connection. The connector is a plumbing connector for use with a plastic pipe P. This may be a single layer plastic pipe but is more commonly a multi-layered pipe (MLCP). As can best be seen, for example, in Fig. 5A, the multi-layered pipe has a number of layers, typically inner and outer polymeric layers and an intermediate layer of a metal such as aluminium. Plumbing connectors must be suitable for being used in both cold and hot water systems as well as in heating systems. As such, they must be able to cope with a continuous temperature of 95°C and must also be able to cope with temperatures of above 100°C for short periods. The connector is made from a body 1, an O-rings 2, a collet 3, a locking cap 4 and transparent ring 5. The body 1 is a double-ended body such that it has O-rings 2, collet 3, locking cap 4 and transparent ring 5 at either end. The components are preferably high performance polymers. For example the body 1 may be unfilled PPSU / PSU / PPS / PVDF. The locking cap 4 and collet 3 may be the same materials but these may be glass filled. Other possibilities for the cap and collet may be GF PA66 / PA12 / Amodel / Grivory’ or other suitable polymeric materials. The transparent ring 5 may be Grilamid or fiber reinforced polymer, preferably polycarbonate or polyester. The body 1 has a generally tubular configuration with a throughway 10 extending axially along a main central axis X (Fig. 1B). At the proximal end (i.e. the end closest to the open end of the connector, the distal end being the opposite end furthest from the open end), the body 1 has a tubular portion 11 over which the pipe P is received as shown, for example, in Fig. 6. Part way along the tubular portion 11 are a pair of annular grooves 12 each of which receives a respective O-ring 2. As shown in various figures, the O-rings 2 seal with the inner diameter of the pipe P. The collet 3 has a lip 30 at one end via which it is received, for example as a snap fit into a groove 14 in the body 1. The outer face of the collet 3 is provided with a screw thread 31 (Figures 5A and 6A). The locking cap 4 has a complementary screw thread 40 such that the locking cap 4 can be rotated with respect to the collect to lock the connector as described in greater detail below. As well as the screw-threaded engagement, the locking cap 4 is also captive on the collet 3. The collet 3 is provided with a plurality of first axial slots 32 (Figures 4A and B) extending distally from the proximal end. A plurality of second axial slots 34 extend proximally from the opposite distal end of the collet and these axially overlap with the first axial slots 32 but are circumferentially offset with respect to these slots. The collet 3 is made of a relatively rigid material and the slots provide the necessary flexibility for the collet to be fitted in place. This is done by forcing the collet 3 over the tubular portion 11 until the lip 30 snaps in the groove 14. A number of detents 15 are provided at the distal end of the tubular portion 11 which engage complementary grooves 34A in the collet arranged at or near the mid-point between adjacent second axial slots 34 to substantially prevent or inhibit rotation of the collet 3 with respect to the body 1. The collet 3 is thereby axially and radially fixed with respect to the body 1. With the collet 3 fixed in place, the locking cap 4 is then pressed on to the collet 3. The first axial slots 32 allow the distal end of the collet to compress and allow the locking cap 4 to be pressed onto the collet at least until some the part of the screw thread 31 engages with part of the screw thread 40. The collet may be pushed to a desired location at which the two screw threads 31,40 begin to engage. However, for a more reliable engagement, the locking cap 4 is pressed onto the collet beyond the unlocked position and the locking cap 4 is then screwed back to the unlocked position shown in Fig. 1 A. When the locking cap 4 is in the unlocked position, an inwardly extending annular shoulder 41 engages with a complementary outwardly extending shoulder 310 on the collet as best shown in Fig. 5A. This provides a stop to ensure that the locking cap 4 cannot be unscrewed beyond this unlocked position, thereby holding the locking cap 4 captive on the collet 3. The first axial slots 32 also serve to separate the proximal end of the collet 3 into separate legs 35 e.g., four separate legs 35. There could be a different number of first axial slots 32 and therefore a corresponding different number of legs 35, such as three or five etc. Each leg 35 has an inner tooth 36 and an outer tooth 37 closer to the proximal end of the collet than the inner tooth 36. The teeth 36, 37 are axially aligned with the O rings 2. Distally of the inner tooth 36 is a pipe receiving portion 38 with an inner diameter which receives the outer diameter of the pipe P. The collet has an inward bulge 37A between the two sets of teeth 36, 37. In the unlocked configuration shown, for example, in Fig. 5A, at the distal face of the connector, the inner diameter is significantly larger than the outer diameter of the pipe P. This can be seen in Fig. 5A where the innermost edge 39 of the proximal end of the collet is spaced from the pipe P. The connector is supplied in this unlocked configuration to an end user. This configuration of connector is depicted in Figs 1 A, 2A and 3A. In this unlocked configuration, the pipes P can be inserted into the connector. They are fully inserted to the position shown in Figs 1B, 2B, 3B, 5 and 5A. The connector is specifically designed to provide a low insertion force for the pipe P. A number of features of the design allow for this. These are described in WO2022 / 018413 (incorporated by reference). This also describes a mould for making the collet. The transparent ring 5 is fitted onto the collet 3 which holds it in place as shown in Figure 6 against a flange 311 at the distal end of the collet 3. The transparent ring 5 has an annular shape and is provided with a generally frustoconical face 51 and curved castellations 52 in the distal end of its inner face. Some of these castellations 52 engage with projections 312 on the collet 3 extending proximally from the flange 311. These prevent rotation between the collet 3 and ring 5. As is apparent from the figures as the castellations 52 extend around the whole ring 5, the ring can be inserted in any rotational orientation and will locate on the projections 312. As seen in Fig 6A the end of the pipe P in the fully inserted position extends distally beyond the end of the locking cap 4 in the locked configuration by a small amount Z. The frustoconical face 51 of the transparent ring 5 is oriented to face the exposed end of the pipe P. This allows the end of the pipe P to be clearly viewed by an operator. This is particularly the case when there is a high contrast between the pipe P, which is typically white, and the body 1 and collet 3 which can be a dark colour, preferably black. This provides an indication that the pipe is fully inserted both before and after the connector is locked. The ability to view the pipe directly enhances the reliability of this operation compared to a visual indicator which relies on seeing a secondary component. Figure 6A is a cross-section in a plane away from the second axial slot 34 such that, in this plane, the pipe P cannot be seen from outside the connector as it is obstructed by the collet 3. However, in a plane containing a second axial slot 34 there is a direct line of sight through the transparent ring 5 and the end of the slot 34 to the end of the pipe P. If the connector is being made up by hand, it is not possible for the locking cap 4 to be over-tightened as the geometry of the connector can be made such that it is not possible to advance the locking cap 4 any further using only a manual force. In the event that the user is using a tool, the tool can be provided with a torque limiting feature which can limit the torque which can be applied via the tool at a level well below that which is likely to cause damage to the connector. Further, once the locking cap 4 is fully tightened, the operator can easily view the end of the pipe P through the transparent ring 5 to provide reassurance that the pipe P is correctly located. This can be substantially more reliable than a connector which only relies on the movement of a secondary component in order to verify the correct location. Also, the above described arrangement of the shorter locking cap 4 and the presence of a transparent ring 5 means that the presence of the pipe P can be verified even when the connector is being used in a tight or cluttered space. The locking cap 4 is provided with a plurality of axially extending grooves 46 which are designed to allow the application of a tool which has a complementary geometry. The grooves 46 are open at the proximal end 47 and closed at the distal end 48 such that the tool can be slid in the distal direction onto the locking cap 4 until it reaches the closed end 48. Alternatively, the tool may be applied in a radial direction. As will be apparent from Figures 3A to 3C, the grooves 46 have a uniform depth along their length. Thus, whichever part of the groove 46 the tool engages with, it will have a uniform and reliable interaction with the end cap 4 such that the tool can reliably rotate the end cap 4 with the possibility of slippage or twisting of the tool being minimised. A feature to prevent overtightening is provided by a plurality of flexible tabs 54 which extend proximally from a proximal face of the ring 5 as best shown in Figure 7B, these are arranged circumferentially, and are angled to be are complementary with saw tooth shaped projections 44 which extend around the circumference of the inner face of the distal end of the locking cap 4 as best shown in Figs. 7B and 8. When the locking cap 4 reaches the fully locked position, the saw tooth shaped projections 44 engage with the flexible tabs 54. Rotation of the locking cap 4 causes the flexible tabs 54 to be deformed radially inwardly as they ride up the ramp surface of a respective saw tooth shaped projection 44. As each flexible protrusion reaches the end of the saw tooth shaped projection 44, it abruptly falls off the end face of the ramp onto the adjacent saw tooth shaped projection creating an audible click. Because the flexible tabs 54 are arranged at an angle, they are essentially aligned with the ramp face of the saw tooth shaped protrusion 44 thereby avoiding contact between the saw tooth shaped protrusion 44 and an edge of the flexible tab 54 which might cause snagging and undue wear. The audible signal is enhanced by the fact that ring 5 is not a tight fit against the adjacent part of the collet 3. As a result of this, the ring 5 is free to vibrate with respect to the collet 3 and this enhances the audible signal. This is achieved by the fact that the inner diameter of the ring 5 is slightly larger than the outer diameter of the adjacent part of the collet 3 creating a clearance 55 between the two as shown in Fig. 5A. The clearance is maintained by the manner in which the collet 3 engages with the body 1 as described above. In particular, engagement between the protrusions 15 and the grooves 34A means that relative rotation between the body 1 and the collet 3 is achieved in a manner which does not cause undue deflection of the segments of the collet 3 between the adjacent grooves 34. As a result of this, the clearance 55 can be reliably maintained. As well as providing an audible signal, the flexible tabs also provide an element of tamper-5 proofing. As is apparent from Fig. 7B, once the locking ring 4 is in its fully locked position, in order to unlock it, it is necessary to rotate it in the opposite direction from that previously described. As a result of this, the end face of each saw tooth shaped protrusion 44 pushes against a side of an adjacent flexible tab 54 which will cause it to be deformed. This deformation is not enough to render the connector inoperable. However, it does provide a 10 diagnostic tool for investigation into a subsequent failure of the connector.

Claims

1. A pipe connector comprising:a hollow body having a central throughway defining an axis, the body comprising a tubular part at at least one end, the tubular part having an outer face to seal, in use, with an inner diameter of a pipe placed over the tubular part;a collet fitted over the tubular part of the body so as to be axially fixed with respect to the body and being spaced from the tubular part to form a cavity for the pipe, the inner face of the collet being configured to grip the pipe, in use, and the outer face of the collet having a first screw thread;a locking cap having an inner face with a second screw thread which is complementary to the first screw thread, wherein screwing the locking cap onto the collet from an unlocked configuration to a locked configuration causes inward deflection of the collet to press, in use, the collet onto the pipe and the pipe onto the tubular part to seal the interface between the body and the pipe;wherein the collet has at least one axially extending through slot extending proximally from its distal end to divide the distal end of the collet into a plurality of segments: and;a first location feature at a mid-portion of at least one segment to engage with a complementary second location feature on the body to prevent relative rotation of the collet and body.

2. A pipe connector according to claim 1 wherein the first location feature is a groove.

3. A pipe connector according to claim 1 or claim 2 wherein the first location featureon an internal face of the collet.

4. A pipe connector according to any preceding claim, wherein the first location feature is at a distal end of the collet.

5. A pipe connector according to any preceding claim, wherein a ring is non-rotatably retained with respect to the collet, and saw tooth shaped protrusions are arranged around an inwardly facing surface of the locking cap, the protrusions being positioned to engage with complementary flexible tabs on the ring when the locking cap reaches a fully locked position such that relative rotation of the cap with respect to the body causes the saw toothshaped projections to repeatedly deflect the tabs radially inwardly to generate an audible noise.

6. A pipe connector according to claim 5, wherein the inner diameter of the ring is larger than the outer diameter of the part of the collet that it is retained on in an unstressed state.

7. A pipe connector according to claim 5 or claim 6, wherein the flexible tabs are angled at a complementary angle to ramp faces of the saw tooth shaped protrusions.

8. A pipe connector according to any preceding claim, wherein a pair of O rings are provided on the outer face of the tubular part to seal, in use, with the pipe.

9. A pipe connector comprising:a hollow body having a central throughway defining an axis, the body comprising a tubular part at at least one end, the tubular part having an outer face to seal, in use, with an inner diameter of a pipe placed over the tubular part:a collet fitted over the tubular part of the body so as to be axially fixed with respect to the body and being spaced from the tubular part to form a cavity for the pipe, the inner face of the collet being configured to grip the pipe, in use, and the outer face of the collet having a first screw thread;a locking cap having an inner face with a second screw thread which is complementary to the first screw thread, wherein screwing the locking cap onto the collet from an unlocked configuration to a locked configuration causes inward deflection of the collet to press, in use, the collet onto the pipe and the pipe onto the tubular part to seal the interface between the body and the pipe;wherein a ring is non-rotatably retained with respect to the collet, and saw tooth shaped protrusions are arranged around an inwardly facing surface of the locking cap, the protrusions being positioned to engage with complementary flexible tabs on the ring when the locking cap reaches a fully locked position such that relative rotation of the cap with respect to the body causes the saw tooth shaped projections to repeatedly deflect the tabs radially inwardly to generate an audible noise.

10. A pipe connector according to claim 5, wherein the inner diameter of the ring is larger than the outer diameter of the part of the collet that it is retained on in an unstressed state.5 11. A pipe connector according to claim 5 or claim 6, wherein the flexible tabs areangled at a complementary angle to ramp faces of the saw tooth shaped protrusions.

12. A pipe connector according to any of claims 9 to 11, wherein a pair of O rings are provided on the outer face of the tubular part to seal, in use, with the pipe.Application No: GB2319931.8Examiner: Mr Euros MorrisClaims searched: 1-8Date of search: 11 June 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance A - WO2022 / 18412 A2 (RELIANCE WORLDWIDE CORPORATION UK LTD): Whole document relevant A - WO2022 / 018413 Al (RELIANCE WORLDWIDE CORPORATION UK LTD): Whole document relevant.Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if combined with one or more other documents of same category. P Document published on or after the declared priority date but before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO &US patent documents classified in the following areas of the UKCX :Worldwide search of patent documents classified in the following areas of the IPC____________F16L_________________________________________________________The following online and other databases have been used in the preparation of this search reportInternational Classification:Subclass Subgroup Valid From F16L 0033 / 22 01 / 01 / 2006 F16L 0019 / 00 01 / 01 / 2006 F16L 0037 / 091 01 / 01 / 2006 F16L 0037 / 10 01 / 01 / 2006 F16L 0037 / 113 01 / 01 / 2006 F16L 0047 / 04 01 / 01 / 2006Application No: GB2319931.8Examiner:Miss Monika RamelClaims searched: 9-12Date of search: 16 January 2025Patents Act 1977Further Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance JtS A A 9-11 GB 2625100 A (RELIANCE WORLDWIDE CORPORATION UK LTD) Page 17 lines 1-10, Figures 14A and 14B US 2023 / 0265952 Al (RELIANCE WORLDWIDE CORPORATION UK LTD) Figures 3, 4, 11B, 24 GB 2597494 A (RELIANCE WORLDWIDE CORPORATION UK LTD) Figures 3, 4 and 11BCategories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From F16L 0033 / 22 01 / 01 / 2006 F16L 0019 / 00 01 / 01 / 2006 F16L 0037 / 091 01 / 01 / 2006 F16L 0037 / 10 01 / 01 / 2006 F16L 0037 / 113 01 / 01 / 2006Subclass Subgroup Valid From F16L 0047 / 04 01 / 01 / 2006

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