GB2215798A

GB2215798A - Pipe jointing tool

Info

Publication number: GB2215798A
Application number: GB8807270A
Authority: GB
Inventors: John Clements; Clive Lumb; Victor Saywell
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-03-26
Filing date: 1988-03-26
Publication date: 1989-09-27
Also published as: GB8807270D0

Abstract

A pipe jointing tool comprises a body (10), two clamping arms (28), and a turnable clamping handle (22) for releasably clamping the body to the end of a pipe. An actuating bar (46) projects from the body and is movable by a handle (38) to apply a force in the longitudinal direction of the pipe to push or pull a sleeve longitudinally into position across the pipe joint. The invention simplifies the manoeuvring of sleeves across pipe joints, both in the laying of new pipework and in the repair or modification of existing pipework. <IMAGE>

Description

Title: Pipe Jointing Tool Field of the invention This invention relates to a pipe jointing tool for use in making pipe joints, either in new pipe runs or in the repair or modification of existing pipe runs.

Background to the invention Joints in pipes such as drainage pipes are made with the aid of a sleeve (sometimes called a coupling) which overlaps the pipe ends. In laying new pipework, the end of the last pipe section laid has a sleeve previously fitted thereon, and a new pipe section is offered up to the end of the last pipe section laid. The new pipe section is then inserted into the sleeve by the combination of manually pushing on the new pipe section and pulling on the sleeve. To repair or modify an existing pipe run, the damaged length (or the length requiring modification) is cut out by a chain cutter leaving facing ends of pipework.

A new pipe section with a sleeve on each end is located in the gap between the facing ends of pipework. The sleeves are then pushed from the new pipe section onto the facing ends so that the sleeves overlap the joints. Both in the laying of new pipework and in the repair or modification of existing pipework, the manoeuvring of the sleeves across the joints is a difficult and awkward task, frequently made more difficult by the confined space and adverse environment of a trench. The invention aims to provide a pipe jointing tool which facilitates the positioning of coupling sleeves across pipe joints.

Summary of the invention According to the invention a pipe jointing tool comprises a body, clamping means for releasably clamping the body to a pipe and actuating means operative to apply a force in the longitudinal direction of the pipe to push or pull a sleeve longitudinally into position across a pipe joint.

The clamping means may comprise two arms which embrace the pipe and a manually turnable member for tightening the arms so as to anchor the jointing tool on the pipe. Once anchored on the pipe, the actuating means are operated to push or pull the sleeve into the required position overlapping the pipe ends, after which the clamping means are released to enable the tool to be removed from the pipe.

The actuating means may include a bar which projects from the body and engages the sleeve to impart a pulling or pushing force thereto. In a preferred construction the bar projects longitudinally from the body and has on its end remote from the body a yoke shaped to engage the sleeve. The actuating means are preferably manually operable, conveniently by a handle which is pivotally movable with respect to the body so as to impart a pushing or pulling movement to the bar. The range of pivotal movement of the handle preferably corresponds to the required stroke of the bar, substantially equal to half the length of the sleeve to be drawn across the joint.

In a possible modification, a manually operative member serves both to operate the clamping means and the actuating means, for example by arranging for a first part of the movement of the member to clamp the body on the pipe and a further part of the movement of the member to move the bar longitudinally.

A pipe jointing tool according to the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a side view of the pipe jointing tool with an operating lever shown in two alternative positions; Figure 2 is an end view of the pipe jointing tool, and: Figure 3 is a sectional view on the line 33 of Figure 1; The pipe jointing tool has a body 10 comprising two side plates 12 rigidly interconnected by a top plate 14. The upper portions of the side plates 12 are in spaced parallel relationship and these portions of the side - plates have vertically elongated slots 16 best shown in Figure 3. Below these parallel portions, the side plates 12 are splayed apart and terminate in out turned lips 18.

A pin 20 extends through the two slots 16 and is adjustably movable in a vertical direction in the slots 16 by means of a clamping handle 22. The clamping handle 22 is attached to a shank 24 which is threaded through a bore in the pin 20. Hence, rotation of the clamping handle 22 causes the pin 20 to move up and down, guided by the slots 16.

The pin 20 carries spaced brackets 26 which are welded to the upper ends of clamping arms 28. The arms 28 extend downwardly through apertures 30 in the side plates 12.

Commencing from the upper ends of the clamping arms 28 where the latter are attached to the brackets 26, the clamping arms first diverge and then converge, so that the two clamping arms 28 cooperate to embrace a pipe such as that shown at 32 in the drawings. It will be appreciated that rotation of the clamping handle 22 clockwise as viewed from above draws the pin 20 upwardly in the slots 16 and this causes the clamping arms 28 to be drawn upwardly and inwardly towards one another so as to apply a progressive clamping action onto the pipe 32. This tightening by hand minimises the risk of over-tightening, which carries the risk of damaging the pipe. The arms 28 are released by screwing the clamping handle 22 anticlockwise as viewed from above, enabling the tool to be lifted away from the pipe.Hence, the clamping arms, the brackets 26, the pin 20 and the clamping handle 22 enable the pipe jointing tool to be clamped in a desired position on the pipe 32.

Referring to Figure 1, a lever 34 is pivotally mounted on a pin 36 spanning the side plates 12. The lever 34 is welded to the lower end of a handle 38 which has a hand grip 40 at its end remote from the body 10. The lower edge of the lever 34 has an open ended slot 42 within which is located a transverse pin 44 carried by a bar 46.

The bar 46 is guided for longitudinal movement with respect to the body 10 by means of spaced pairs of guide pins 48, 50. At its end remote from the body 10, the bar 46 carries a yoke 52 which embraces the pipe 32 with a small amount of clearance.

Figure 1 shows the lever in full lines in its lowered position (corresponding to a retracted position of the bar 46) and in broken lines in its raised position (corresponding to the extended position of the bar 46).

It will be realised that the clamping tool can be clamped in position on a pipe and the handle 38 pivoted upwards or downwards to impart to the bar 46 an extending or retracting movement, so as to apply a pulling or pushing force to a joining sleeve.

Assume a pushing action is required to effect the insertion of a new section of pipe in an existing pipe run. With the push/pull bar 46 fully retracted and the repair sleeve pushed fully onto the new section of pipe, the tool body 10 is clamped in position on the new section of pipe, as previously described, such that the yoke 52 is in contact with the repair sleeve. The jointing tool has a stroke action which automatically ensures that the repair sleeve is placed in the correct position exactly over the pipe joint. By operating the lever handle 38 an axial thrust is applied to the sleeve, thus completing the joint. The clamping handle 22 is released, permitting the removal of the tool from the pipe, so completing the operation.

Assume a pulling action is required to effect the laying of new sections of pipe in a new pipe run. With the push/pull bar 46 fully extended and the joining sleeve pushed onto the last section of pipe laid, the next section of pipe is prepared by fitting a joining sleeve onto the free end. The tool body 10 is clamped to the plain end of this pipe such that when lowered into the pipe trench the yoke 52 is located over and behind the joining sleeve on the last section of pipe laid. By operating the lever handle 38 an axial thrust is applied to the sleeve, thus drawing the new pipe into the joining sleeve of the last pipe laid and effecting the joint. The clamping handle 22 is released, permitting the removal of the tool from the pipe, so completing the operation.

The described pipe jointing tool has the following advantages: 1. Reduces physical effort.

2. Speeds up the pipe jointing process, especially difficult access repairs to existing pipe runs.

3. Reduces neccessity for wide trenches to permit the operator to climb into the trench.

4. Can be operated from ground level with extended clamp screw and operating lever.

5. Permits the use of narrow trenching machines giving reduced spoil removal.

6. Can be used for repairing or modifying existing pipe runs as well as laying new pipe.

7. Can be operated by hand, requires no other power source.

8. All metal construction with no loose parts to get lost.

9. Strong, maintenance free construction will operate in wet and muddy conditions.

10. Can be assembled to provide push down or pull up action, with either push or pull fitting of sleeve.

11. Lightweight, portable and compact to fit into confined spaces and narrow trenches 12. Fits over the pipe from above and does not need to surrond pipe completely, so clearance below pipe not necessary. Less digging (and less infilling afterwards) is required.

13. The tool can be used with plastics, ceramic or metal pipes.

14. The stroke of the lever handle 38 is set to match the required amplitude of movement of the sleeve, so that a properly made joint is assured each time.

15. The bar 46 may be interchanged with a bar having a yoke of different size, to suit different sizes of pipe.

Claims

1. A pipe jointing tool comprising a body, clamping means for releasably clamping the body to a pipe and actuating means operative to apply a force in the longitudinal direction of the pipe to push or pull a sleeve longitudinally into position across a pipe joint.

2. A pipe jointing tool according to claim 1, wherein the clamping means comprise two arms which embrace the pipe and a manually turnable member for tightening the arms so' as to anchor the jOiflti ng tool on the pipe.

3. A pipe jointing tool according to claim i or 2, wherein ne actuating weans include a bar which projects from the body and engages the sleeve to impart a pulling or pushing force thereto.

4. A pipe jointing tool according to claim 3, wherein the bar prc,ects longltudinally from the body and has on its end remote from the body a yoke shaped to engage the sleeve.

5. A pipe jointing tool according to any of the preceding claims, wherein the actuating means are manually operable.

6. A pipe jointing tool according to claim 5, wherein the actuating means are operated by a handle which is pivotally movable with respect to the body so as to impart a pushing or pulling movement to the bar.

7. A pipe jointing tool according to claim 1, wherein a manually operable member serves both to operate the clamping means and the actuating means.

8. A pipe jointing tool according to claims 3 and 7, wherein a first part of the movement of the member clamps the body on the pipe and a further part of the movement of the member moves the bar longitudinally.

9. A pipe jointing tool constructed and arranged substantially as herein particularly described with reference to the accompanying drawings.