GB2346651A - Support clamp - Google Patents

Abstract

A clamp the jaws of which have pronounced sharp teeth enabling it to be clamped on to soft timber such as ceiling joists. A fixed horizontal support <B>4</B> attached to one jaw of the clamp provides support for panel products, such as plasterboard, while these are being fixed, for example to a ceiling. A ratchet-operated clamp lock <B>3</B> provides a secure means of fixing the clamp in position while in use.

Description

SUPPORT CLAMP The invention relates to a support clamp which, when fastened to a ceiling joist, aids the fixing of panels such as plasterboards by providing a solid support upon which to rest one side of such a panel.

The normal procedure for fixing plasterboard etc is as follows : It takes two people to fit a 240 cm x 120 cm (8'x 4') sheet. Both people lift the sheet, and one positions themself beneath it, balancing it on his head and hands which makes his own balance very unstable. He then has to push the sheet up to the ceiling joists and hold it in position while the second person nails it to the joists. The sheet must be nailed securely around all its edges before the first person can release it. Holding the sheet is a very difficult and tiring job, especially when working off stepladders.

The support clamps I have designed comprise of two crossed handles connected by a central bolt and operating toothed jaws, a pivotal clamp lock operated by a ratchet system by means of which the jaws of the clamp can be locked in the required position, and a fixed horizontal support attached to one jaw of the clamp, and will support one side of a plasterboard in position relieving the workers of at least half the sheet's weight. Only one side of the sheet now needs to be nailed before it can be released, which frees both people to finish nailing the sheet, thus substantially reducing fitting time per sheet. In addition, because only one side of the sheet needs to be held, working off stepladders is made much safer.

Accordingly, these clamps provide good solid anchorage on a joist by which a panel can be securely supported.

The clamps are preferably made of steel to provide strength and allow good leverage, ensuring a secure fixing to a joist. The teeth on the clamp are sharp enough to sink into a wooden joist making it very safe to load weight onto the clamp. Preferably, rubber or plastic tubing covers the handles to make using the clamp more comfortable.

With just two of these clamps, smaller sheets of ceiling material ; such as 180 cm x 90 cm (6'x 3') plasterboard, can easily be fitted by just one person.

The clamps are operated very easily with one hand. When closed the clamp lock 3 works automatically on a ratchet system, holding the clamp firmly closed.

Releasing the clamp is also simple. The end of the clamp lock 3 is pushed down, unlocking the mechanism, while the top edge of the clamp lock 3 pushes against the edge of side 1 so forcing the clamp open.

A specific embodiment of the invention will now be described by way of example, with reference to the accompanying drawings in which: Figure 1 shows the clamp fixed to a joist, front view and side view Figure 2 shows the separate parts that make up the clamp Figure 3 shows the method of fitting the clamp at the correct distance along the joist Figure 4 shows the side view of sheet supported by clamp Figure 5 shows the problem with sagging of long lengths of timber As shown in Figure 1, the metal teeth on 1 and 2 sink into the wooden joist, then the clamp lock 3 holds the clamp firmly closed. The panel support 4 extends to the rear of the clamp, to prevent the clamp from twisting on the joist, when the plasterboard is placed onto it. A measuring string 5 is fitted to the clamp to aid positioning of the clamp along the joist, as shown in Figure 3.

Figure 2 shows the separate pieces that make up the clamp. The left handle 1 has a spur 6 fixed to it; this is to hold the clamp lock 3 in the desired position ensuring the clamp stays closed. The panel support 4 is fixed to the right handle 2. The measuring string 5 is fixed to the panel support 4.

Figure 3 shows the method of positioning the clamp on the joist at the correct distance from the previously fixed plasterboard. This is achieved by use of the measuring string. If the plasterboard being fitted is 120 cm (4') wide, the measuring string should be 125 cm (4'1") long. The loose end of the string is held against the edge of the previously fixed plasterboard then the clamp is extended along the joist until the string is taut. The clamp is now fitted to the joist.

With a second clamp fitted in the same position on an appropriately adjacent joist, the plasterboard can be installe. First one side is rested on the panel supports, then the other side can be pushed up to the joist and butted up to the previously fixed plasterboard as shown in Figure 4. At this point the plasterboard is firmly anchored to the joists, although it can still be moved around until it is in its final position. The plasterboard can now be nailed along the unclamped side after which it no longer needs to be held by either person, so allowing both to complete the nailing. The clamps can now be released and the process is repeated with the next sheet. Figure 5 demonstrates a problem that occurs when fixing long lengths of tongue and groove timber which are prone to sagging, making the insertion of the tongue into the groove very difficult. The problem can be overcome by fitting three or more clamps in appropriate positions across the joists and resting the plank on the panel supports so keeping it straight and aiding insertion of tongue into groove.

Claims (3)

1. CLAIMS 1 A clamp comprising two crossed handles connected by a central bolt and operating toothed jaws, a pivotal clamp lock operated by a ratchet system by means of which the jaws of the clamp can be locked in the required position, and a fixed horizontal support attached to one jaw of the clamp.
2. 2 A clamp as claimed in Claim 1 wherein a measuring string is attached to provide a simple means of measurement.
3. 3 A clamp as claimed in Claim 1 or Claim 2 wherein a rubber or plastic or other soft material is used to cover the lower part of each handle.