A HAND TOOL

This invention relates to a hand tool, and in particular a hand tool for use with a T-shaped plumbing fitting.

During DIY activities or general household maintenance it is often necessary to remove a radiator from its plumbing fittings, or rotate the radiator relative to the plumbing fittings so as to, for example, replace the radiator or provide temporary access to a wall area behind the radiator.

Typically a radiator is connected into a plumbing circuit via a radiator valve at each end thereof. The radiator valve has a generally T-shaped configuration with one end of a cross member having a plumbing pipe connected thereto, and the other end of the cross member including a valve that allows a user to isolate the radiator. A leg of the radiator valve extends perpendicularly to the cross member, and is typically connected to the radiator by a compression fitting.

In order to remove or rotate the radiator a user must undo or loosen the compression fitting to allow movement of the radiator relative to a given radiator valve. To prevent leaks the compression fitting is usually tightened to such an extent that a user must use a spanner to undo the compression fitting.

Attempting to undo the compression fitting using a spanner imparts high bending stresses on the plumbing pipe which normally extends perpendicularly to the compression fitting and is restrained by a support surface such as a wall or a floor.

Such stresses on the plumbing pipe cause the walls of the pipe to collapse leading to bending, which can result in catastrophic failure and rupture of the plumbing pipe.

Similarly, tightening the compression fitting following replacement of the radiator to its original position also causes bending stresses in the plumbing pipe which can lead to the same problems as those outlined above.

Therefore there is a need to prevent bending of plumbing pipes during removal and connection of radiator valves to a radiator in order to obviate the aforementioned problems.

According to the invention there is provided a hand tool, for use with a plumbing fitting, comprising a pair of opposed jaws extending laterally from a handle towards one end thereof, at least one jaw including a generally planar engagement surface extending therefrom at an angle to the length of the handle.

The inclusion of at least one jaw having a generally planar engagement surface extending therefrom at an angle to the length of the handle provides a surface which a user is able to abut against the cross member of a radiator valve. Abutting the engagement surface against the radiator valve in this way prevents rotation of the radiator valve about an axis passing through the centre of the leg of the valve, while loosening or tightening the compression fitting. Avoiding rotation of the radiator valve prevents bending of the plumbing pipe connected thereto during removal and connection of a radiator valve to a radiator. In addition, avoiding such rotation helps to prevent a threaded connection between the radiator valve and a radiator becoming undone which could cause a leak.

Preferably each jaw includes a generally planar engagement surface extending therefrom at an angle to the length of the handle. Such an arrangement assists a user in abutting the engagement surfaces against the radiator valve.

Optionally the generally planar engagement surfaces lie parallel to one another. Having parallel engagement surfaces helps to ensure that they remain abutted against the radiator valve during use of the hand tool.

The generally planar engagement surfaces may extend in the same direction. This configuration allows a user to prevent rotation of the radiator valve in both clockwise and anti-clockwise directions, thereby enabling the user to both loosen and tighten a compression fitting without having to change the orientation of the hand tool relative to the radiator valve.

In another preferred embodiment of the invention the generally planar engagement surfaces extend in opposite directions. Such an arrangement increases the moment that the hand tool is able to impart on the radiator valve, for a given length of handle, so as to continue preventing rotation of the valve under high loading.

The or each generally planar engagement surface may extend from first and second sides of a respective jaw. This configuration helps to distribute the loading on the jaws of the hand tool while providing large engagement surfaces to abut a radiator valve.

Conveniently one jaw is moveable relative to the other jaw to vary the spacing between the jaws. This allows a user to use a single hand tool with a range of radiator valves of differing size.

Preferably at least one jaw includes an indicator to indicate the spacing between the jaws. As a result a user is able readily to adjust the spacing between the jaws to suit a particular task.

Optionally one jaw is separable from the other jaw. Such an arrangement allows for cleaning of the jaws following use.

There now follows a brief description of a preferred embodiment of the invention, by way of non-limiting example, with reference to the accompanying drawings in which:

Figure 1 shows a perspective view of a hand tool according to a first embodiment of the invention; Figure 2 shows another perspective view of the hand tool shown in Figure 1 ; and

Figure 3 shows a perspective view of the hand tool shown in Figure 1 engaged with a radiator valve.

A hand tool according to a first embodiment of the invention is designated generally by the reference numeral 10.

The hand tool 10 includes a pair of opposed jaws 12, 14 which extend laterally from a handle 16 towards one end 18 of the handle 16.

In the embodiment shown, each jaw 12, 14 includes a generally planar engagement surface 20 that extends from the respective jaw 12, 14 at an angle to the length L of the handle 16. In another embodiment of the invention, only one jaw 12, 14 includes the engagement surface 20. In a further embodiment of the invention, at least one jaw includes a recess extending at an angle to the length of the handle. The or each such recess helps a user to align the jaws with a plumbing fitting. In a preferred embodiment of the invention, the or each jaw includes a pair a planar engagement surfaces inclined relative to one another to define a recess therebetween.

In the embodiment shown, the engagement surfaces 20 lie parallel to one another. Other embodiments of the invention may include engagement surfaces that are arranged at an angle to one another.

The engagement surfaces 20 extend from first and second sides 22, 24 of each jaw 12, 14.

Each jaw 12, 14 may also include a removable sleeve (not shown) to protect a plumbing fitting from damage.

One jaw 12 is moveable relative to the other jaw 14 to vary the spacing between the jaws 12, 14. In this regard, the moveable jaw 12 is moveably received within a guide slot 26 located in the other jaw 14, and includes a toothed rack 28. The toothed rack 28 engages with a rotatable helical screw member 30 mounted in the other jaw 14. Rotation of the helical screw member 30 is translated into linear movement of the toothed rack 28 which causes movement of the moveable jaw 12 relative to the other jaw 14.

The other jaw 14 includes an indicator 32 in the form of a series of lines 1mm apart to indicate the spacing between the jaws 12, 14.

The moveable jaw 12 is separable from the other jaw 14 to facilitate cleaning of the jaws 12, 14.

In use, a user adjust the spacing between the jaws 12, 14, as desired, before abutting each engagement surface 20 against a cross member 34 of a radiator valve 36.

The engagement surfaces 20 prevent rotation of the radiator valve 36 about an axis A passing through the centre of a leg 38 of the valve 36 while a user loosens or tightens a compression fitting 40 that secures the valve 36 to a radiator 42. Avoiding rotation of the radiator valve 36 in this way prevents bending of a plumbing pipe 44 connected to the radiator valve 36 during removal and connection of the radiator valve 36 to a radiator 42.

A user may also abut each engagement surface 20 against the spout of a tap (not shown) to restrain the tap during, for example, removal of various fixtures therefrom.