GB2485293A

GB2485293A - Fastening pin

Info

Publication number: GB2485293A
Application number: GB1200196.2A
Authority: GB
Inventors: Peter Julian Owen; Jonathan Bloy
Original assignee: Raptorgrip Ltd
Current assignee: Raptorgrip Ltd
Priority date: 2009-10-02
Filing date: 2009-10-02
Publication date: 2012-05-09
Also published as: GB201200196D0

Abstract

A fastening pin comprises a threaded head portion 10 and a threaded shank extending 11 from the head 10 to a tip 9 . The tip 9 has a cutting portion suitable for cutting into a substrate.

Description

A Fastening Assembly The present invention relates to a fastening pin for use in a fastening assembly for the attachment of objects to a substrate, especially, though not exclusively weak or soft construction material substrates, especially such substrates as plasterboard or other friable or weak materials, such as chipboard or medium density fibreboard (mdf), although may also be used for wood.

It is generally appreciated that the use of plasterboard as a construction material has introduced difficulties for the support of wall mounted functional and decorative fittings and fixtures such as sinks, light fittings, bathroom furniture, curtain rails etc. The friable nature of plasterboard means that it tends to crumble around the area adjacent a screw driven therein. This results in a loosening of the screw and thus of any bracket attached to it leaving both liable to fall out.

The problem is particularly acute where substantial load is placed onto the bracket, e.g. bathroom furniture such as a sink, or where the object is subjected to repeated or cyclic stresses.

In a similar manner, it is known that connecting chipboard or mdf together, or fastening objects to substrates made of chipboard or mdf or similar materials is difficult as, again, these materials tend to crumble around the area adjacent a screw driven therein, which results in a loosening of the screw and a reduction on the integrity of the connection or fastening.

Previous methods devised to overcome this problem include using large threaded screws or by clamping the bracket against both sides of the substrates.

CH693100 describes a bracket bent such that the apertures are aligned at an angle about 30°.

In orthopaedic surgery, it is known to use bracing plates having threaded apertures adapted to retain and lock a fastening screw. As described in US2001021951, these plates are used to brace broken bones to facilitate mending of fractures.

It is therefore an object of the present invention to provide a fastening device for a bracket that will overcome, or at least reduce the disadvantages of the known systems.

Accordingly, the invention provides a fastening pin comprising a threaded head portion having a thread configured in a conical helix, a threaded shank extending from the head to a tip having a cutting portion suitable for cutting into a substrate.

Preferably, the threaded head portion is enlarged or enlargening from the shank.

In a preferred embodiment, the threaded shank has a thread having a smaller external diameter than the thread of the head portion.

The head portion preferably defines a tool engageable structure for enabling the pin to be rotated into the substrate using a suitable tool.

The term bracket' in the context of this specification will be taken to mean a support or connector adapted to be affixed to a substrate forming a wall, ceiling or other similar surface, or to a door, doorframe or other building element, or to a part of furniture, for example flat pack furniture, so as to hold or bear the weight of an object mounted thereto.

Locking of the fastening pin directly to the bracket prevents or at least substantially inhibits the ability of the fastening pin to move independently from the bracket and therefore improves the bracket's retention to the substrate.

The locking action may take the form of a frictional tightening between the fastening pin and the bracket in addition to the frictional contact that is typically experienced between the cooperation of two threads.

Having the thread defined on the head allows the fastening means to be partially or fully received within the aperture thereby enabling an object to be mounted onto the bracket without being obstructed by a protruding fastening means.

The invention will now be described by way of embodiment with reference to the following figures in which: Figure 1 is a plan, side and bottom view of a fastening pin for attaching a bracket to a substrate according to one embodiment of the present invention; Figure 2 is a plan, side and bottom view of a second fastening pin for attaching a bracket to a substrate according to one embodiment of the present invention; Figure 3 is a top plan view of a bracket for use with the present invention; Figure 4 is a top plan view of a bracket for use with the present invention; Figure 5 is a top plan view of a bracket for use with the present invention; Figure 6 is an end edge view of the bracket of Figure 5; Figure 7 is a bottom plan view of the bracket of Figure 5; Figure 8 is a side edge view of the bracket of Figure 5; Figures 9 to 12 similar views to Figures 5 to 8 of the bracket with fastening pins passing therethrough; Figures 13 to 16 are similar views to Figures 9 to 12 with the fastening pins passing through the bracket at a different angle to that of Figures 9 to 12.; Figures 17 to 20 are similar views to Figures 5 to 8 of a bracket for use with the present invention; Figures 21 to 24 are similar views to Figures 17 to 20 of the bracket with fastening pins passing therethrough; Figures 25 to 28 are similar views to Figures 5 to 8 of a bracket for use with the present invention with a guide adapter in position to guide fastening pins into the bracket; Figures 29 to 32 are similar views to Figures 25 to 28 of the bracket with a different guide adapter in position after the fastening pins have been guided into the bracket; and Figures 33 to 36 are similar views to Figures 25 to 28 of the bracket with the guide adapter removed after the fastening pins have been guided into the bracket.

Thus, Figure 1 shows a fastening pin for fastening a bracket to a substrate. The fastening pin 8 has a cutting portion 9 and an enlarged head portion 10 at either end of a shank 11. Head portion 10 defines shoulders 12 defining a conical external thread 13. Defined within the end of head portion 10 is a recess 14 shaped for engagement with a tool e.g. screwdriver such as a Philips cross-screw, Allen key etc. The size of head portion 10 and slope of shoulder portions 12 are chosen to allow the head 10 to seat within an aperture in the bracket such that thread 13 is engageable with the edges of the apertures as will be more fully described hereafter.

Figure 2 shows a similar fastening pin to that of Figure 1, but, in this case, the shank 11 is provided with a thread 15 having an external diameter smaller than that of the head portion 10.

Figure 3 illustrates a first embodiment of a bracket 1 having a substantially planar portion 2 having a plurality of apertures 3. In this case six such apertures 3 are shown, but it will be appreciated that any appropriate number could be provided depending on the application, though it is preferred that at least two, preferably at least three apertures are used. As best seen in Figure 6, the bracket I includes a hook portion 4 substantially parallel to the planar portion 2 and joined thereto by an angled joining portion 5. Strengthening ribs 6 are provided in the planar portion 2 surrounding elongate apertures 7 used to reduce the overall weight of the bracket 1. The apertures 3 are obround shaped defined by an obround shaped wall. The apertures may be punched out from the planar portion 2 of the bracket 1 or may be otherwise formed depending on the thickness of the planar portion 2.

Figure 4 illustrates a second embodiment of a bracket 1 similar to that of Figure 3, with the same elements having the same reference numerals as in Figure 3. The elements which are the same will not be described again. As can be seen, in this embodiment, the apertures are generally elongate star-shaped defined by a zig-zag shaped wall. Figures 5 to 8 illustrate a third embodiment of a bracket 1, again with the same elements (which will not be described again) having the same reference numerals as in Figure 3. The apertures 3 are again star-shaped defined by zig-zag shaped walls, but in this embodiment, they are not elongate, but generally symmetrical about a central point.

Figures 9 to 12 show the bracket of the third embodiment with very similar views to those of Figures 5 to 8, but with fastening pins 8 similar to those of Figure 1 inserted through the apertures. As can be seen, the pins are driven into the substrate 16, shown in Figure 11, but not shown in Figures 9, 10 and 12 for clarity, at diverging angles. In particular, in this case, the pins are arranged to diverge at an angle of about 30° to the perpendicular to the planar portion 2 of the bracket, or to the surface 17 of the substrate 16 against which the planar portion 2 abuts. In this example, it can be seen that the outer pins of each of the two rows of three pins also diverge from the other pins in that row. The divergence of the pins provides much greater strength of fastening of the bracket to the substrate than pins that are driven into the substrate in parallel and perpendicular to the surface of the substrate. As the pins 8 are rotated into the substrate 16, the shank of the pins passes through the apertures, but the threaded head with its thread configured in a conical helix begins to engage the side wall of the aperture 3. In the case of the star-shaped apertures, it first engages with the innermost points of the zig-zag shaped wall and, as the fastening pin 8 is rotated further, the thread on the head portion engages further with the wall of the aperture and locks with it.

The angle at which the fastening pins are driven into the substrate can be determined by a guide adaptor, as will be described further below, or by the shape and size of the aperture. Thus, for example, the elongate star-shaped apertures of the second embodiment of the bracket, or the obround apertures of the first embodiment guide the fastening pins to be driven at an angle along the direction that they are elongate in. Of course, if the planar portion has a sufficient thickness, then the apertures can be formed with an axis through the planar portion of the bracket which diverges from perpendicular with respect to the plane of the planar portion. This will also guide the fastening pin being driven through the aperture to go through the substrate at an angle that diverges from the perpendicular.

Where possible, the length of the pins 8 are chosen such that the cutting portion 9 will protrude through to the other side of the substrate 16 before the threads 13 engage with the wall of the apertures 3. This is to preclude rotation of the pin 8 causing the bracket to be raised away from the surface of the substrate rather than causing the cutting portion 9 to penetrate further into the substrate 16. Where an adequate pin length can not be selected because the substrate is very thick, e.g. a breeze block, the hole may be predrilled before the pin is inserted.

To affix the bracket I to the substrate 16, the portion of the bracket defining the apertures 3 is held generally flush against the surface 17 of the substrate 16. A pin 8 is first positioned within aperture 3 and driven into the substrate 16 as a temporary fix. In some cases, a first pin may be driven in perpendicularly to enable easier first entry into the substrate surface 17 whilst the bracket I is not self-supported. Cutting portion 9 of the pin 8 acts to bore a channel in the substrate 16 for the shank 11 to pass through. Once the first pin 8 is secured, the remaining pins can be located and driven in.

Each pin 8 is driven until head 10 seats sufficiently into the aperture 3 that conical threads 12 are engaged. Further driving of the pin 8 causes the shoulder/thread 12, 13 to forcefully abut and be compressed against the wall of the aperture. This may also be accompanied by slight plastic deformation of the pin/thread 8/12 and/or the wall of the aperture 3.

With the pin 8 locked to the bracket 1, a substantially increased level of torque is required to rotate the pin 8 out from the locked position. This inhibits independent movement of the pin 8 from the bracket 1 and vice-versa thereby inhibiting the bracket's 1 ability to be moved from its affixed position.

Figures 13 to 16 show essentially the same embodiment as Figures 9 to 12, but where the pins are driven into the substrate 16 at an angle of about 45° to the perpendicular to the planar portion 2 of the bracket, or to the surface 17 of the substrate 16 against which the planar portion 2 abuts. Again, it can be seen that the outer pins of each of the two rows of three pins also diverge from the other pins in that row.

Because each of the pins 8 diverge, movement of the bracket 1 away from its fixed position will be will be resisted as the vector of the force will be at least partially transverse to the axis of at least one of the pins. Equally, as the pins are locked to the bracket 1, stress upon the bracket will not allow subsequent movement or play of the pins 8 which would otherwise accelerate loosening.

Modifications of the above assembly are possible, for example, the bracket may comprise any number of apertures 3 for receiving the corresponding number of pins 8, however it is preferred that at least three pins are used to achieve adequate attachment.

Although preferred, it is not necessary for all three pins to diverge and be located in more than one plane. For example, if there are two pins and apertures, they could be parallel, although extending non-perpendicularly to the bracket. In this case, both pins could extend downwardly into the substrate, so that the weight of the bracket (and whatever is supported on the bracket) is used to maintain the bracket in position against the plasterboard.

In a fourth embodiment, as shown in Figure 17 to 20, an upper surface of the planar portion 2, opposite to a surface that abuts the surface 17 of the substrate 16, may be provided with guides 18 around each aperture 3. The guides 18 are preferably part cylindrical in shape and extend at an angle around at least part of the apertures 3. In this way, they can guide the respective fastening pin entering the respective aperture at the correct angle to diverge from the perpendicular to the planar portion. Thus, the pin can be guided at the correct angle, irrespective of whether the aperture itself is formed with an axis through the planar portion at an angle that diverges from the perpendicular, or whether the aperture is formed in a relatively thin planar portion and is simply punched out of the material forming the planar portion. In the latter case, the guides 18 can, of course, be punched out of the material forming the planar portion, being formed by the same punching operation as that forming the apertures and being formed from the material punched out to form the apertures.

Figures 21 to 24 show the bracket of the fourth embodiment with very similar views to those of Figures 17 to 20, but with fastening pins 8 inserted through the apertures 3.

Figures 25 to 28 show similar views to those of Figures 5 to 8, but, in this case, the bracket 1 is provided with only three apertures 3. The apertures 3 are shown as having a generally symmetrical star-shape, although any of the previously described shapes could be used instead. Figures 25 to 28 show a guide adapter having a generally cuboid or box-like structure with a first surface 21 for abutting against the upper surface of the planar portion 2 of the bracket 1, and an opposed second surface 22 spaced apart from the first surface 21. The first and second opposed surfaces 21, 22 are connected by side walls 23, 24, which may extend beyond the first surface to provide an abutting wall 25 for abutting an edge of the planar portion 2 in order to easily position the guide adapter 20 over the planar portion 2. The first and second surfaces 21, 22 are provided with corresponding apertures 26, 27 offset with respect to each other through which the fastening pins 8 are positioned so as to be guided into the generally star-shaped or obround apertures at angles which diverges from perpendicular with respect to the planar portion 2 of the bracket. The corresponding apertures are joined by generally cylindrical guide walls 28 extending between the first and second surfaces 21, 22.

Each cylindrical guide wall 28 is provided with a plurality of guide ribs 29 extending radially inwardly so as to abut the fastening pin 8 but to provide less frictional resistance to its rotation as it is being driven into the substrate than if the pin contacted the whole of the guide wall 28.

Figures 29 to 32 show similar views to those of Figures 25 to 28, but, in this case, the cylindrical guide walls 28 do not have the guide ribs 29. Furthermore, the pins 8 are shown having been driven into the substrate 16.

Finally, Figures 33 to 36 show similar views to those of Figures 29 to 32, but, in this case, the guide adapter 20 has been removed after the pins have been driven into the substrate 16. Accordingly, these Figures are substantially the same as the views shown in Figures 9 to 12, except for the number of apertures 3 in the bracket 1.

It will be appreciated, that although the fastening pins shown with respect to most of the embodiments are similar to the pin of Figure 1, the pin of Figure 2 could alternatively be used. In this case, the thread 15 on the shank 11 of the pin 8 will engage with the substrate 16. The invention may equally be applied to other forms or shapes of bracket other than that shown. For example, they could be L' shaped, or of any other suitable shape, depending on the application for which they are to intended be used.

The fastening kit, although especially useful for weak or soft construction material substrates, especially such substrates as plasterboard or other friable or weak materials, such as chipboard or medium density fibreboard (mdf), may also be used for wood (whether softwood or hardwood.

By having pins of different lengths available, it is easy to fix the brackets to hollow walls or doors, or to solid ones, even if there is a construction material deeper behind the substrate through which the pins cannot pass, e.g a metal lintel over a door or window frame where a curtain fixing bracket may be placed. In this case, a shorter pin is chosen, which does not reach the metal lintel and the hole formed remains small in diameter and the plasterboard is not damaged as happens when a screw or rawlplug is screwed into a wall and then encounters the lintel, at which point it rotates without moving deeper and damages the hole already made.

Finally, in many instances, precise bracket placement is achieved without the necessity for prior measurement and marking of the wall, because a rapid, easy placement on the wall is achieved, with immediate fixing of the pins to the substrate.

It will also be appreciated that although only a few particular embodiments of the invention have been described in detail, various modifications and improvements can be made by a person skilled in the art without departing from the scope of the present invention. -11 -

Claims

Claims 1. A fastening pin comprising a threaded head portion having a thread configured in a conical helix, a threaded shank extending from the head to a tip having a cutting portion suitable for cutting into a substrate.
2. A fastening pin according to claim 1, wherein the threaded head portion is enlarged or enlargening from the shank.
3. A fastening pin according to either claim 1 or claim 2, wherein the threaded shank has a thread having a smaller external diameter than the thread of the head portion.
4. A fastening pin according to any one of claims I to 3, wherein the head portion defines a tool engageable structure for enabling the pin to be rotated into the substrate using a suitable tool.
5. A fastening pin according to any one of claims 1 to 4, wherein the substrate is formed of a weak or soft construction material.
6. A fastening pin for supporting an object onto a substrate substantially as hereinbefore described with reference to Figure 2 of the drawings.