GB2161236A

GB2161236A - Masonry fixing device

Info

Publication number: GB2161236A
Application number: GB08416795A
Authority: GB
Inventors: Peter Louis Lunn
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-07-02
Filing date: 1984-07-02
Publication date: 1986-01-08
Also published as: GB8416795D0

Abstract

A fixing device 10 for use with a wood screw 17 is formed from sheet metal into a tube so as to have one slit 12 from end to end and another slit 18 part-way along the tube from the rear end 14. The front end 13 of the tube is partly closed in to form a nose with a hole 15 for the tip 16 of the screw 17. The edge of the hole 15 is shaped to engage the thread of the screw. The length of the device 10 is less than four times its maximum diameter. In use, penetration of the device 10 by the screw 17 expands the front end 13 of the tube so as to increase the maximum diameter of the device 10. In use, a hole 19 is drilled in masonry 20, device 10 is inserted into the hole 19 part-way along the length of the hole 19 and the "wood" screw 17 is then screwed home so that it expands the device 10, which thereby becomes securely fixed in the masonry. This applies to non-yielding masonry such as brick work. For yielding masonry, particularly porous masonry the fixing device may be hammered into the masonry using a setting tool 22. <IMAGE>

Description

SPECIFICATION "Masonry fixing device" This invention relates to a fixing device for use in masonry with a screw having a tapered end.

According to the invention there is provided a fixing device for use in masonry with a screw having a tapered end, comprising a generally tubular member formed from sheet metal into a tube so as to have a slit from end to end, one end of the tube being partly closed in to form a nose with a hole for the tip of the screw, the edge of the hole being shaped to engage the thread of the screw, the length of the device being less than four times its maximum diameter, whereby in use penetration of the device by the screw expands said one end of the tube so as to increase the maximum diameter of the device.

The invention will be described by way of exam ple with reference to the accompanying drawings, wherein Figures 1, 2 and 3 are perspective views of a fixing device embodying the invention, Figure 1 being a view from the front and one side, Figure 2 being a view from the front and the opposite side and Figure 3 being a view from the rear and one side; Figure 4 illustrates the device of Figures 1 to 3 in juxtaposition with a screw having a tapered end; Figure 5 illustrates the device and the screw of Figure 4, with the screw about to be screwed home into some masonry to fix e.g. wood to the masonry; Figure 6 corresponds to Figure 5, with the screw screwed home; and Figure 7 illustrates a setting tool.

Referring to Figures 1 to 3 of the drawings, the fixing device 10 comprises a generally tubular member 11 formed from sheet metal into a tube so as to have a slit 12 extending from the front end 13 to the rear end 14. The front end 13 of the tube is partly closed in to form a nose, with a hole 15 for the tip 16 (Figure 4) of the screw 17, which has a tapered end as shown, being an ordinary 'wood' screw, that is to say, a wood designed for screwing into wood (not being designed for screwing into masonry). The edge of the hole 15 is shaped to engage the thread of the screw. The length of the device 10 is less than four times its maximum diameter.

The nose formed by the front end 13 of the device 10 is curved in a plane normal to the axis of the tube (see Figures 1 and 2) and is also curved in planes in which the axis of the tube lies, as will be apparent from Figures 4 and 5. That is to say, the nose is curved in two dimensions.

The slit 12 extends longitudinally of the tube, whilst a second slit 18 extends part-way along the tube from the rear end 14.

In use, a hole 19 is drilled in the masonry 20 and through e.g. wood 21 which is to be fastened to the masonry. Then the device 10 is inserted, front end 13 first, into the hole 19 so that the device 10 finishes up part-way only along the hole 19, as shown in Figures 5 and 6. In order to position de vice 10 thus, it may be positioned on the front end of the screw 17 as shown in Figure 5 and the screw pushed in, without turning, until device 10 reaches the desired position. Alternatively, a set ting tool such as tool 22 of Figure 7 may be used to push the device 10 into hole 19. The next step is for the screw 17 to be driven home, that is to say, turned by means of a screwdriver (not shown) so as to expand the front end 13 and thus increase the maximum diameter of the device as shown in Figure 5.To some extent, the masonry becomes indented by the device 10 so that it cannot there after move forwards or backwards along the hole 19, hence securely holding the screw 17, the thread of which screw-threadedly engages the front end 13 of the device 10. In addition, the device 10, being made of metal, has inherent springiness so that continual pressure is exerted between the device 10 and the masonry 20.

It will be appreciated that the device 10 can be readily and cheaply made from strip metal by means of a press, and that it enables an ordinary "wood" screw to be used in masonry as shown, the only requirement being the drilling of a hole to take the device 10 in the first place.

The setting tool 22 has a projecting pin 22a at its front end, with a shoulder 22b for pushing device 10 (shown in chain-dot lines only in Figure 7) to be pushed into the hole 19.

Pre-drilling of a hole is necessary for masonry which is non-yielding, for example, brick work, concrete and clinker blocks. However, using the setting tool 22, the device 10 may be hammered into yielding masonry, particularly porous masonry such as that sold under the Registered Trade marks "THERMALITE", "DUROX" and "SIPOREX".

1. A fixing device for use in masonry with a screw having a tapered end, comprising a generally tubular member formed from sheet metal into a tube so as to have a slit from end to end, one end of the tube being partly closed in to form a nose with a hole for the tip of the screw, the edge of the hole being shaped to engage the thread of the screw, the length of the device being less than four times its maximum diameter, whereby in use penetration of the device by the screw expands said one end of the tube so as to increase the maximum diameter of the device.

2. A fixing device as claimed in claim 1 wherein the nose of the device is curved in a plane normal to the axis of the tube and in planes in which the said axis lies.

3. A fixing device as claimed in claim 1 or 2 wherein the slit extends longitudinally of the tube.

4. A fixing device as claimed in claim 1, 2 or 3 wherein a further slit extends part-way along the tube from the rear end.

5. A method of fixing a screw in masonry by means of a device as claimed in any preceding claim, comprising the steps of inserting the device into a preformed hole in the masonry and then

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION "Masonry fixing device" This invention relates to a fixing device for use in masonry with a screw having a tapered end. According to the invention there is provided a fixing device for use in masonry with a screw having a tapered end, comprising a generally tubular member formed from sheet metal into a tube so as to have a slit from end to end, one end of the tube being partly closed in to form a nose with a hole for the tip of the screw, the edge of the hole being shaped to engage the thread of the screw, the length of the device being less than four times its maximum diameter, whereby in use penetration of the device by the screw expands said one end of the tube so as to increase the maximum diameter of the device. The invention will be described by way of exam ple with reference to the accompanying drawings, wherein Figures 1, 2 and 3 are perspective views of a fixing device embodying the invention, Figure 1 being a view from the front and one side, Figure 2 being a view from the front and the opposite side and Figure 3 being a view from the rear and one side; Figure 4 illustrates the device of Figures 1 to 3 in juxtaposition with a screw having a tapered end; Figure 5 illustrates the device and the screw of Figure 4, with the screw about to be screwed home into some masonry to fix e.g. wood to the masonry; Figure 6 corresponds to Figure 5, with the screw screwed home; and Figure 7 illustrates a setting tool. Referring to Figures 1 to 3 of the drawings, the fixing device 10 comprises a generally tubular member 11 formed from sheet metal into a tube so as to have a slit 12 extending from the front end 13 to the rear end 14. The front end 13 of the tube is partly closed in to form a nose, with a hole 15 for the tip 16 (Figure 4) of the screw 17, which has a tapered end as shown, being an ordinary 'wood' screw, that is to say, a wood designed for screwing into wood (not being designed for screwing into masonry). The edge of the hole 15 is shaped to engage the thread of the screw. The length of the device 10 is less than four times its maximum diameter. The nose formed by the front end 13 of the device 10 is curved in a plane normal to the axis of the tube (see Figures 1 and 2) and is also curved in planes in which the axis of the tube lies, as will be apparent from Figures 4 and 5. That is to say, the nose is curved in two dimensions. The slit 12 extends longitudinally of the tube, whilst a second slit 18 extends part-way along the tube from the rear end 14. In use, a hole 19 is drilled in the masonry 20 and through e.g. wood 21 which is to be fastened to the masonry. Then the device 10 is inserted, front end 13 first, into the hole 19 so that the device 10 finishes up part-way only along the hole 19, as shown in Figures 5 and 6. In order to position de vice 10 thus, it may be positioned on the front end of the screw 17 as shown in Figure 5 and the screw pushed in, without turning, until device 10 reaches the desired position. Alternatively, a set ting tool such as tool 22 of Figure 7 may be used to push the device 10 into hole 19. The next step is for the screw 17 to be driven home, that is to say, turned by means of a screwdriver (not shown) so as to expand the front end 13 and thus increase the maximum diameter of the device as shown in Figure 5.To some extent, the masonry becomes indented by the device 10 so that it cannot there after move forwards or backwards along the hole 19, hence securely holding the screw 17, the thread of which screw-threadedly engages the front end 13 of the device 10. In addition, the device 10, being made of metal, has inherent springiness so that continual pressure is exerted between the device 10 and the masonry 20. It will be appreciated that the device 10 can be readily and cheaply made from strip metal by means of a press, and that it enables an ordinary "wood" screw to be used in masonry as shown, the only requirement being the drilling of a hole to take the device 10 in the first place. The setting tool 22 has a projecting pin 22a at its front end, with a shoulder 22b for pushing device 10 (shown in chain-dot lines only in Figure 7) to be pushed into the hole 19. Pre-drilling of a hole is necessary for masonry which is non-yielding, for example, brick work, concrete and clinker blocks. However, using the setting tool 22, the device 10 may be hammered into yielding masonry, particularly porous masonry such as that sold under the Registered Trade marks "THERMALITE", "DUROX" and "SIPOREX". CLAIMS

5. A method of fixing a screw in masonry by means of a device as claimed in any preceding claim, comprising the steps of inserting the device into a preformed hole in the masonry and then driving the screw through the device so as to expand said one end of the tube.

6. A method of fixing a screw in low density masonry by means of a device as claimed in any one of claims 1 to 4, comprising the steps of hammering the device into the masonry to form its own hole and then driving the screw through the device so as to expand said one end of the tube.