GB2478118A

GB2478118A - Expandable pipe connector

Info

Publication number: GB2478118A
Application number: GB1003093A
Authority: GB
Inventors: David Brain; Ronnie Brain
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-02-24
Filing date: 2010-02-24
Publication date: 2011-08-31
Also published as: GB201003093D0

Abstract

A pipe connector is provided to join broken ends of a pipe, particularly an exhaust pipe, by being fitted inside the ends of the fractured pipe in an un-expanded state before being expanded in order to press against the broken pipe's internal faces to clamp fast thereto. The pipe connector 200 comprises an expandable tube, and an expanding element that is operable to increase the diameter of the expandable tube, where the expandable tube has an elongate axis, a continuous split 210 from one end to the other of the expandable tube providing two opposed distal faces of the expandable tube which can be moved apart to increase the diameter of the expandable tube. The expanding element may comprise a saddle plate that is constrained to move away from an internal area of the expandable tube by an anchor. A method of joining a pipe using an expandable connector is also claimed.

Description

IMPROVED PIPE CONNECTOR AND METHOD THEREOF

The present invention relates to a pipe connector for connecting distal ends of two pipes. In particular, the present invention relates to a pipe connector for repairing a vehicle's exhaust pipe that has fractured into two components.

Pipe connectors for repairing a vehicle's exhaust pipe are known. Known pipe connectors comprise a sheet of metal that has been rolled into a generally tubular shape wherein the ends of the tubular sheet are arranged to overlap. The rolled metal sheet is inserted into the inside of distal ends of two pipes (i.e. to extend into either side of the fractured exhaust pipe). The diameter of the rolled metal sheet is then expanded, reducing the amount of overlap, by moving the distal ends towards each other. Consequently the pipe connector pushes against the inside of the pipes and secures them together.

As shown in Figure 1, a known pipe connector 10 comprises a rolled metal sheet 12. The metal sheet 12 has a central aperture and is rolled about its length so as to form a tubular part.

Distal ends 13, 14 of the rolled metal sheet 12 are arranged to overlap each other to form an overlapping section 15. Consequently, the aperture is arranged substantially opposite the middle of the overlapping section. A nut 16 is welded to the inside of the rolled metal sheet 12 and coincident with the aperture. A bolt 18 is arranged to engage the nut 16 so that the bolt 18 can be urged to extend further into the rolled metal sheet 12 by threaded connection between the nut 16 and the bolt 18. The bolt 18 has a domed cap 19 screwed on it's distil end.

In use, the known pipe connector 10 is arranged within a broken exhaust pipe 20. Thus the pipe connector 10 is arranged to extend into either side of the broken exhaust pipe 20 with the nut 12 extending from beneath the break in the exhaust pipe. The pipe connector 10 can then be expanded by tightening the bolt 12 within the nut 14 such that the domed cap 19 moves away from the nut 14. Accordingly, the domed cap 19 abuts the inside wall of the overlapping section 15 and causes the rolled metal sheet to expand. It will be appreciated that, for the rolled metal sheet's diameter to increase, the distal ends 13, 14 are intended to move toward each other with the inherent resiliency of the rolled metal sheet maintaining a generally tubular form. The tightening continues until the pipe connector 10 has expanded against the inside faces of the exhaust pipe 20 (as shown in Figure 2). Thus the pipe connector 10 provides a temporary fix in order to reconnect the two ends of the broken exhaust pipe 20.

It has been found that, in use, such pipe connectors are often disassembled for ease of insertion into the broken exhaust pipe. For instance, the domed cap 19 is removed from the bolt 18 and the bolt 18 completely unscrewed from the nut 16. Then, the rolled metal sheet 12 is inserted completely into one side of the broken exhaust pipe 20. Next, the other side of the broken exhaust pipe is brought into register with the side containing the pipe connector 10.

The rolled metal sheet 12 is then urged to extend out of the first pipe and into the other side of the broken exhaust pipe by urging it along the pipe using an operative's finger tips. Once the pipe connector has been urged sufficiently so that the nut 16 is accessible through the join of the broken pipes, the bolt 18 can then be reinserted into the nut 16 and tightened as before.

However, it will be appreciated that the domed cap 19 is not able to be reattached to the bolt's distal end. Moreover, it will be appreciated that the disassembly and reassembly is time consuming and complicated by roadside conditions. Furthermore, it is undesirable to provide unassembled parts as these may become misplaced.

It has been found that, during use, the domed cap 19 often nips against the rolled metal sheet.

Such nipping acts to prevent the two ends of the rolled metal sheet 12 from sliding over the other part of the metal sheet. Consequently, rather than expanding the diameter of the rolled metal sheet 12, tightening the bolt 18 within the nut 16 can cause the rolled metal sheet 12 to become deformed. This problem is emphasised when the domed cap 19 is removed.

It is an object of the present invention to attempt to overcome at least one of the above or other disadvantages. It is a further aim to provide a pipe connector that can be easily and quickly installed within two ends of a broken exhaust pipe. It is a further aim to provide a pipe connector that is expandable in a consistent and reliable manner. It is a further aim to provide a pipe connector with reduced assembly operations.

According to the present invention there is provided a pipe connector and method of joining two pipes as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

According to a first aspect of the present invention there is provided a pipe connector comprising an expandable tube. The expandable tube is elongate and has a continuous slit running from one axial end of the expandable tube to another. The continuous slit forms two opposed distal faces. An expanding means is provided to cause the expandable tube to increase in diameter. The expanding means being operable to cause the distal faces to move away from each other in order to increase the diameter of the expandable tube.

According to an exemplary embodiment, the expanding means comprises a saddle plate that is constrained to move away from an internal area of the expandable tube by an actuator. In these embodiments, the actuator is able to rotate with respect to the expandable tube but is restrained from moving toward or away from the expandable tube by an anchor. The anchor is fixed to the expandable tube but does not extend outward from the external diameter of the expandable tube even when in use. Here the actuator and saddle plate are arranged in a threaded connection. Thus rotation of the actuator causes the saddle plate to move toward and away from the anchor.

In the exemplary embodiments, the pipe connector comprises an increased frictional area.

Preferably the increased frictional area comprises a plurality of ridges that are angled with respect to the elongate axis of the expandable tube.

According to a further aspect there is provided a method of connecting two pipes using a pipe connector of the previous aspect. The method comprises inserting an unexpanded pipe connector into one pipe. Subsequently bringing a second pipe into register with the first but spaced a small distance there from. The method comprising subsequently urging the pipe connector into the second pipe by contacting the part of the pipe connector accessible through the spaced ends of the two pipes. When an actuator of the pipe connector is aligned with the gap, operating an expanding means in order to expand the pipe connector by causing two opposed distal faces of a continuous slit to move away from each other. Continuing to operate the expanding means until the pipe connector is expanded against the inside of the two pipes.

In the exemplary embodiments, the method preferably comprises using an increased frictional area to aid the urging of the pipe connector into the second pipe.

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: Figures 1 and 2 show a cross-sectional view through a prior art pipe connector when inserted into an exhaust pipe 20 in an unexpanded state and expanded state respectively; Figures 3 and 4 show a cross-sectional view through a pipe connector according to a first embodiment of the present invention in an unexpanded state and expanded state respectively; Figure 5 shows a schematic perspective view of an expandable tube for use in a pipe connector in accordance with the first embodiment; and Figure 6 shows a schematic perspective view of a saddle plate for use in a pipe connector in accordance with the first embodiment.

Referring to Figure 3, a pipe connector 100 is provided to join broken ends of a pipe (particularly an exhaust pipe) by fitting inside the ends of the fractured pipe in an un-expanded state before being expanded in order to press against the broken pipes internal faces to clamp fast thereto. The pipe connector 100 comprises an expandable tube 200, and an expanding means that is operable to increase the diameter. The expandable tube 200 has an elongate axis A-A (see Figure 5). A continuous split 210 is formed along the elongate axis and from one end 202 to the other 204 of the expandable tube 200. Consequently, two opposed distal faces 212, 214 of the expandable tube 200 are formed. Thus the diameter of the expandable tube 200 can be increased by moving the two distal faces 212, 214 apart. The expandable tube 200 is sized such that the end faces 212, 214 of a pipe connector 200 suitable for joining a particular diameter of broken pipe, do not overlap when the pipe connector is in an unexpanded state. Consequently the risk of nipping is decreased, if not substantially removed.

The expanding means preferably comprises a saddle plate 300 and an actuator 400. The saddle plate 300 is arranged inside the expandable tube 200 and constrained such that it is substantially moveable only in a radial direction relative to the elongate axis of the expandable tube 200. The actuator 400 acts to urge the saddle plate 300 away from one portion of the internal diameter of the expandable tube 200 such that an opposed area of the internal diameter moves away. Thus the diameter of expandable tube is increased. Preferably, the actuator is arranged radially. Furthermore, preferably the saddle plate 300 is arranged to bridge the continuous split 210 and abut an internal face of the expandable tube 200 in at least two places, one on either side of the continuous split 210. The actuator 400 is arranged to be operable to move the saddle plate away from an opposite side of the inside of the expandable tube. Consequently, the pipe connector 200 can be expanded by operating the actuator 400 in order to cause the saddle plate 300 to urge the end faces 212, 214 to move away from each other. As such, the diameter of the expandable tube 200 is increased. Figures 3 and 4 shows the pipe connector 200 in an un-expanded state and expanded state respectively.

Advantageously, because the saddle plate is constrained not to rotate relative to the expandable tube and because the two ends do not overlap, the risk of nipping the expandable tube is reduced, if not substantially removed. Thus the pipe connector expands reliably and with reduced risk of deforming in the location that the actuator acts.

Preferably, the actuator 400 includes an anchor 410. The anchor 410 (shown in expanded detail in Figure 3) is arranged to fix a portion of the actuator 400 to one side of the expandable tube 200. Here the anchor 410 is arranged to prevent the actuator 400 from protruding from an external diameter of the expandable tube 200. For instance, an access port 411 is provided in the expandable tube 200. The access port 411 enables the actuator 400 to be operated from an outside of the expandable tube. Suitably, as shown in the Figures, the anchor 410 comprises a distal end region of the actuator 400. Here two stops 412, 414 are provided on either side of the access port 411 that is formed through the expandable tube 200.

Consequently, the stops 412, 414 prevent the actuator from moving toward or away from the expandable tube 200 relative to the access port. However, the stops are not secured fast to the expandable tube. Consequently the anchor can still rotate thereto. Thus the actuator can be operated by a rotational actuation method.

Suitably, the access port 411 is a central aperture through which an elongate member 420 is arranged. A head is formed on one end of the elongate member. The head has a larger size than the elongate member and therefore forms the stop 414. It will be appreciated that, in order for the head 414 not to protrude from the external diameter of the expandable tube, the head 414 is preferably tapered and an area 413 that is around the aperture 414 is correspondingly tapered or countersunk. In order not to prevent the tapered head 414 from acting on a thinned area (for instance if the countersink taper was machined), it is preferable to countersink the area 413 surrounding the aperture by a pressing operation. The stop 412 is secured fast to the elongate member and spaced from the head 414. Preferably, the stop 412 is a nut and secured to a threaded portion of the elongate member 420. Thus, advantageously, the nut 412 can be easily assembled to the elongate member 420 and adjustments made in relation to the distance the nut 412 is spaced from the head 414. It is preferable that the nut 412 is welded or otherwise secured to the elongate member. This prevents it from working loose. It also prevents the pipe coupling from being disassembled.

This enables the actuator to be fine tuned to ensure it rotates smoothly relative to the access port. Preferably, the access port is centred and opposed to the continuous split 210.

Consequently the actuator operates radially with respect to the expandable tube 200. Thus abutment between the head and external surface 413 of the expandable tube prevents the elongate member from relatively moving in one axial direction and abutment between the stop 412 and inside surface of the expandable tube prevents the elongate member from relatively moving in an opposed axial direction.

Advantageously, because the actuator 400 does not protrude from the external diameter of the expandable tube 200, the pipe connector 100 does not need to be disassembled in order to fully insert the pipe connector 100 in to a broken pipe. Thus, the pipe connector 100 can be easily and quickly installed within one side of the broken pipe. Once the other side of the broken pipe is brought into register, the pipe connector can then be slid into the other side by using finger tips to encourage the part of the pipe connector accessible through the fracture area to move. When the access port is aligned with the fracture in the pipe, the actuator can be operated and the pipe connector expanded.

In order to aid the urging of the pipe connector into the second pipe, an area having increased friction is provided. The area having increased friction is preferably an elongate area that is arranged parallel with the elongate axis of the expandable tube 200. Preferably, the area having increased friction includes a series of ridges. The ridges are arranged at an angle to the elongate axis such that each ridge provides leverage in order for the finger tips (or a tool such as a screwdriver) to act to aid the urging of the pipe connector along a pipe. Preferably, the area having increased friction is provided by the continuous slit 210. Here, as shown in Figure 5, the continuous slit 210 has a non-linear path such that it oscillates back and forth in a zigzag. Thus edges of the end faces provide angled ridges (or angled slots). The ridges or slots are arranged relative to the elongate axis, which therefore aids the urging of the pipe connector. Advantageously, because the ridges are provided by opposed sides of the slit, the pipe connector is able to be urged in either direction.

In order to further improve the arrangement of the pipe connector within the fractured pipes, an indicator can be provided to indicate when the access port is aligned with the fracture (it will be appreciated that when the access port is central, the mark is visible at the fracture when equal amounts of the pipe connector extend into either end of the fractured pipe). Here, as shown in Figure 5, suitably a mark or flat area is provided. For instance, suitably a portion (and most preferably a central portion) of the continuous slit 210 is arranged to extend axially. In contrast to the portions to either side that extend at angles (zigzags) to the axial direction. Thus, advantageously, a visual indicator is provided to inform the operative that the pipe connector has been moved to the correct position. If necessary, the pipe connector can then be rotated within the pipes so that the actuator 400 is accessible to be operated.

Preferably the actuator 400 is operated by rotational movement. Here an elongate member 420 of the actuator includes a threaded portion that engages and co-operates with a threaded portion of the saddle plate 300. Suitably, the elongate member 420 is shown as including an external thread on its distal end. Here, a threaded boss 310 (Figure 6) is attached to the saddle plate 300. The threaded boss 310 is arranged to be sufficient in length such that an adequate length of thread maintains connection with the thread of the elongate member 420 even when in the expanded state. It will be appreciated that the actuator therefore includes an engaging means such as a splined socket for receiving a tool in order to activate the rotation.

Suitably, as shown in the Figures, a head 414 of the elongate member 420 includes the socket for receiving the tool.

Still referring to Figure 6, the saddle plate 300 is shown as being substantially elongate.

Consequently, rather than the saddle plate acting on at least two discrete points, one on either side of the continuous slit 210, the saddle plate acts on at least two elongate areas. Here each elongate area extends axially with respect to the axis of the expandable tube 200.

Advantageously, this spreads the force applied and provides a more uniform expansion of the tube's diameter. Preferably, the saddle plate can be sized so as to act on substantially the total length of the expandable tube. Suitably, the saddle plate 300 is arcuate. Thus, advantageously, the area of each contact between the saddle plate 300 and expandable tube is increased in the radial direction also. It is advantageous if the saddle plate is arranged to span the continuous slit 210 so that it remains in contact with the inside surfaces of the expandable tube even when in the expanded state.

Consequently there is provided a pipe connector that can be used quickly and conveniently to reattach a fractured pipe. For instance, the pipe connector is particularly useful for temporarily fixing a fractured exhaust pipe. Here, the pipe connector can be used to repair a fracture anywhere between the front manifold and rear of the exhaust. Different sized pipe connectors can be used to repair different sized exhaust pipes. Thus, the expansion percentage can be limited to avoid unduly stressing the expandable tube 200. For instance, a set of six pipe connectors can be provided to cover the range of exhaust pipes currently in use. Each pipe connector being sized, for instance, to optimally repair exhausts having diameters of between around 25-30mm, or 30-35mm, or 35-41mm, or 40-46mm, or 47-53mm, or 55-60 mm.

The material of the pipe connector can be selected to meet the requirements of the particular pipes to be connected. Suitably, to provide a robust repair to an exhaust pipe, the pipe connector can be fabricated from metal. To improve the manufacturability of the expandable tube, rather than being formed from a rolled sheet, the tube can be formed by machining or otherwise forming a slit into a tube.

Although preferred embodiment(s) of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made without departing from the scope of the invention as defined in the claims.

Claims

Claims 1. A pipe connector comprising an expandable tube and an expanding means, wherein the expandable tube is elongate and has a continuous slit running from one axial end of the expandable tube to another such that two opposed distal faces are provided, and the expanding means is arranged to cause the expandable tube to increase in diameter by causing the opposed distal faces to move away from each other.
2. The pipe connector according to claim 1, wherein the expanding means comprises a saddle plate that is constrained to move away from an internal area of the expandable tube by an actuator.
3. The pipe connector according to claim 3, wherein the actuator is able to rotate with respect to the expandable tube but is restrained from moving toward or away from the expandable tube by an anchor.
4. The pipe connector according to claim 3, wherein the anchor is fixed to the expandable tube by two stops that are arranged on either side of an access port through the expandable tube, the stop on the outside of the expandable tube and external side of the access port being correspondingly tapered such that the anchor does not extend outward from the external diameter of the expandable tube even when in use.
5. The pipe connector according to claim 4, wherein the taper around the access port is pressed formed such that the area around the access port extends into the expandable tube.
6. The pipe connector according to any of claims 2 to 5, wherein the actuator and saddle plate are arranged in a threaded connection such that rotation of the actuator causes the saddle plate to move toward and away from an opposed side of the expandable tube.
7. The pipe connector according to any preceding claim, wherein the pipe connector comprises an increased frictional area.
8. The pipe connector according to claim 7, wherein the increased frictional area comprises a plurality of ridges that are angled with respect to the elongate axis of the expandable tube.
9. The pipe connector according to claim 7 or 8, wherein the increased frictional area is provided by the continuous slit.
10. A method of connecting two pipes using a pipe connector, the method comprising inserting an unexpanded pipe connector into one pipe and subsequently bringing a second pipe into register with the first pipe but spaced a small distance there from, the method subsequently comprising urging the pipe connector into the second pipe by contacting the part of the pipe connector that is accessible through the spaced ends of the two pipes, and when an actuator of the pipe connector is aligned with the gap, operating an expanding means in order to expand the pipe connector by causing two opposed distal faces of a continuous slit to move away from each other.
11. The method of claim 10, wherein the method comprises contacting an increased frictional area through the gap between the two pipes in order to urge the pipe connector into the second pipe.
12. The method of claim 11, wherein the pipe connector is as claimed in any of claims ito 9.
13. A pipe connector substantially as herein described and with reference to Figures 3 to 6.
14. A method of connecting two pipes substantially as herein described and with reference to Figures 3 to 6.