Patent Description:
A track-mounted drywall system comprises a series of metal tracks that are attached to the ceiling and floor to provide a frame structure for drywall panels. The tracks are also attached to each other, typically using self-drilling screws, to provide a rigid frame. The tracks typically have an L or T profile for attaching drywall panels to the tracks.

After installation of the tracks drywall screws are used to attach the drywall panels to the tracks. The drywall screws pass through the drywall panels and are typically self-tapping for drilling through, and attaching to, the track. Known drywall screws have a bugle head having a tapered neck between the head and the threaded shank.

<CIT> discloses a screw for fastening a gypsum wallboard to support structures made of different materials. <CIT> discloses a self-drilling screw for use in steel houses.

In accordance with the present disclosure there is provided a drywall screw according to claim <NUM>.

In examples, the drywall screw has an axial direction defined by the threaded shank, and the planar bearing surface is perpendicular to the axial direction.

In examples, the first portion of the threaded shank has a first section with a fixed diameter, the first section extending from the planar bearing surface of the head.

In examples, the first portion of the threaded shank further comprises a tapered section joining the first portion and the second portion of the threaded shank.

In examples, the thread extends at least partially over the second portion, the tapered portion, and the first portion.

In examples, the thread of the threaded shank extends from the planar bearing surface, over the first portion of the threaded shank, including any tapered portion, and at least partially over the second portion of the threaded shank towards a tip of the drywall screw.

In examples, the drywall screw further comprises a self-drilling point. The self-drilling point may be adapted for drilling into metal, in particular steel.

In examples, the second portion is in a conical shape and the second portion extends along nearly an entire length of the threaded shank. Thus, this solution allows to avoid an excessive increase in torque when the diameter is suddenly changed.

In examples, the drywall screw further comprises a tool socket formed in the head and extending into the first portion of the threaded shank.

In examples, the head comprises a top surface, opposite to the planar bearing surface, and the tool socket is formed in the top surface of the head. In examples, the top surface is a planar surface. In examples, a height of the head (i.e., a distance between the planar bearing surface and the top surface) is at most about <NUM> millimetres, for example at most about <NUM> millimetres.

In examples, the threaded shank has a root diameter (diameter of the shaft from which the thread extends) of between about <NUM> millimetres and about <NUM> millimetres. In examples, the drywall screw (from top surface of the head to the point) may have a length of between about <NUM> millimetres and about <NUM> millimetres, for example <NUM> millimetres or <NUM> millimetres. In examples, the first portion of the threaded shank may have a length of between about <NUM> millimetres and about <NUM> millimetres, for example about <NUM> millimetres or about <NUM> millimetres.

In examples, the drywall screw is configured for joining together two metal tracks. In such an example, the two metal tracks may be held by the first portion of the threaded shank. In particular, the first portion of the threaded shank may pass through two sheet portions of the metal tracks to join them together.

Advantageously, the planar bearing surface provides for the head to sit flush on the metal track, allowing a drywall panel to be installed nearly flush on the metal track.

According to the invention, the drywall screw must be suitable for attaching a drywall panel to a metal track. In such an example, the drywall screw may be screwed into the drywall panel and into an underlying metal track. In such an example the second portion of the drywall screw is screwed into the metal track to secure the drywall panel to the metal track.

Advantageously, the drywall screw can alternatively be used to screw together two drywall panels.

Accordingly, the drywall screw of the invention can be used for all of the necessary attachments for joining together metal tracks and drywall panels to install a drywall.

As detailed below, the invention provides a drywall screw that can be used for attaching a drywall panel to a track.

As shown in <FIG>, the drywall screw <NUM> includes a head <NUM> and a threaded shank <NUM> extending from the head <NUM>. The threaded shank <NUM> includes a first portion <NUM> attached to the head <NUM>, and a second portion <NUM> distal from the head. A diameter of the first portion <NUM> of the threaded shank <NUM> is greater than a diameter of the second portion <NUM> of the threaded shank <NUM>. In this example, a tapered section <NUM> joins the first portion <NUM> and the second portion <NUM>.

As illustrated, the head <NUM> includes a planar bearing surface <NUM>. The bearing surface <NUM> is an underside of the head <NUM> that is in contact with the job part when the drywall screw <NUM> is used.

A top surface <NUM> of the head <NUM>, opposite to the bearing surface <NUM>, is also planar. Accordingly, the head <NUM> is in the form of a flat disc at the end of the threaded shank <NUM>.

The top surface <NUM> of the head <NUM> includes a tool socket <NUM>. In this example the tool socket <NUM> comprises a cross head section for receiving a screwdriver. The cross head tool socket <NUM> may be of the Philips type or other. In other examples the tool socket <NUM> may comprise a slotted tool socket for receiving a flat screwdriver. In other examples, the tool socket <NUM> may comprise a combination tool socket (i.e., for receiving cross head or flat screwdrivers), a hexagonal or Allen socket, a square socket, a Torx socket, or any other socket type for driving tools such as screwdrivers.

The tool socket <NUM> extends through the head <NUM> and partially into the body of the first portion <NUM> of the threaded shank <NUM> below. Accordingly, the head <NUM> can be made particularly thin as the tool socket <NUM> is accommodated in the first portion <NUM> of the threaded shank <NUM>. In addition, the first portion <NUM> of the threaded shank <NUM> can accommodate a deeper tool socket <NUM> to improve reliability and reduce the risks of stripping the drywall screw <NUM>.

The drywall screw <NUM> also includes a self-drilling point <NUM> at the distal end of the second portion <NUM> of the threaded shank <NUM>. As explained further hereinafter, the self-drilling point <NUM> is preferably adapted to drill into metal, in particular steel.

As shown most clearly in <FIG>, the drywall screw <NUM> has a longitudinal axis <NUM> defining an axial direction of the drywall screw <NUM>. The planar bearing surface <NUM> of the head <NUM> is perpendicular to the longitudinal axis <NUM>. The first portion <NUM> of the threaded shank <NUM> is joined to the head <NUM> with minimal radius in between, so that an edge of the first portion <NUM> and the planar bearing surface <NUM> are perpendicular and joined without any taper or radius therebetween. As explained further hereinafter, this permits the drywall screw <NUM> to be driven into a track or drywall board so that the head <NUM> is substantially flush with the track or drywall board.

As illustrated, a thread <NUM> extends along the drywall screw <NUM>. The thread <NUM> extend from the planar bearing surface <NUM>, or from immediately adjacent to the planar bearing surface <NUM>. The thread <NUM> extends over the entire first portion <NUM> of the threaded shank <NUM> and over the tapered section <NUM> of the threaded shank <NUM>. The thread <NUM> extends partially along the second portion of the threaded shank <NUM> towards the point <NUM>.

<FIG> illustrates dimensions of one particular example drywall screw <NUM>, but it will be appreciated that various drywall screws can be provided in different sizes. In particular, in the example shown in <FIG> the threaded shank <NUM> has a root diameter of <NUM> millimetres, and in various other examples the threaded shank <NUM> may have a root diameter of between about <NUM> millimetres and about <NUM> millimetres.

In the example illustrated in <FIG> the drywall screw <NUM> has a length (In examples, from top surface <NUM> of the head <NUM> to the point <NUM>) of about <NUM> millimetres, and in various other examples the drywall screw <NUM> may have a length (from top surface <NUM> of the head <NUM> to the point <NUM>) of between about <NUM> millimetres and about <NUM> millimetres, for example <NUM> millimetres.

In the example illustrated in <FIG> the first portion <NUM> of the threaded shank <NUM> has a length of <NUM> millimetres measured between the planar bearing surface <NUM> and the beginning of the tapered section <NUM>. In various other examples the first portion <NUM> of the threaded shank <NUM> has a length of between about <NUM> millimetres and about <NUM> millimetres, for example about <NUM> millimetres.

In examples, the thread <NUM> is configured for drywall panels and metal tracks. In particular, the thread may be a fine thread having a thread angle of approximately <NUM> degrees. The thread <NUM> may comprise a twin thread. The height of the thread may be between about <NUM> millimetres and <NUM> millimetre, depending on the size of the drywall screw <NUM>.

<FIG> illustrates use of the drywall screw <NUM> to attach a drywall panel <NUM> to a track <NUM>, in particular to a sheet portion <NUM> of the track <NUM>. The track <NUM> is typically made of metal, such as steel. As shown, the drywall screw <NUM> has been screwed through the drywall panel <NUM> and the sheet portion <NUM> of the track <NUM>. The self-drilling tip <NUM> has cut the path, particularly through the sheet portion <NUM> of the track <NUM>. The head <NUM>, in particular the planar bearing surface (<NUM>, see <FIG>) is in contact with the outer surface <NUM> of the drywall panel <NUM>. The first portion <NUM> of the threaded shank <NUM> is accommodated in the drywall panel <NUM>. The second portion <NUM> of the threaded shank <NUM> is attached to the sheet portion <NUM> of the track <NUM>.

<FIG> illustrates use of the drywall screw <NUM> to attach a first track <NUM> to a second track <NUM>. Such an attachment may be made when building a grid of tracks for later installation of drywall panels by the attachment illustrated in <FIG>. The first and second tracks <NUM>, <NUM> are made of metal, in particular steel.

As shown in <FIG>, the drywall screw <NUM> has been screwed through a sheet portion <NUM> of the second track <NUM> and a sheet portion <NUM> of the first track <NUM>. The self-drilling point <NUM> has cut through the material of the sheet portions <NUM>, <NUM> and the thread <NUM> has gripped the first and second sheet portions <NUM>, <NUM> to attach them to each other.

As shown, the first portion <NUM> of the threaded shank <NUM> joins the first and second sheet portions <NUM>, <NUM> together. The larger diameter of the first portion <NUM> provides an increased holding force and stronger attachment between the sheet portions <NUM>, <NUM>.

As shown, the head <NUM> is flush against the second sheet portion <NUM>, such that the planar bearing surface (<NUM>, see <FIG>) is flat against the second sheet portion <NUM>. Accordingly, the head <NUM> does not protrude much above the surface of the second sheet portion <NUM>, and a drywall panel can be installed on the second drywall section <NUM> without the need to countersink or recess the drywall panel to take account of the head <NUM>.

Accordingly, as illustrated in <FIG> and <FIG> the same drywall screw <NUM> can be used to attach together two tracks <NUM>, <NUM> (i.e., a track-to-track attachment) and also to attach a drywall panel <NUM> to a track <NUM> (i.e., a board-to-track attachment). Accordingly, the installers need fewer types of fastener when installing a drywall system. In addition, the flush head <NUM> (with planar bearing surface <NUM> and planar top surface <NUM> - see <FIG>) means that the installer does not have to recess or countersink fasteners to prevent problems with alignment. Accordingly, installation of a drywall system is faster and more convenient.

In one another embodiment described on <FIG>, the ratio between the first portion <NUM> and the second portion is changed compared to the previous embodiment. In this embodiment, the length of the threaded shank <NUM> corresponds nearly to the length of the second portion. As for the previous embodiment, the thread <NUM> still extends from the planar bearing surface <NUM> of the head <NUM>. In this embodiment, the second portion <NUM> is in a conical shape along nearly an entire length of the threaded shank <NUM>. Thus, this solution allows to avoid an excessive increase in torque when the diameter is suddenly changed. In this embodiment, the other features previously described are unchanged, for example radius, pitch or the like. For a conical shape, one preferred embodiment is to have a smooth transition between the first portion and the portion For example, a conical shape with a little ramp like two or three degrees measured at the middle of the shank <NUM>.

Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to", and they are not intended to (and do not) exclude other components, integers or steps.

Claim 1:
A drywall screw (<NUM>) for a track-mounted drywall system for attaching a drywall panel to a track, the drywall screw comprising a head (<NUM>) and a threaded shank (<NUM>) having a thread (<NUM>) joined to the head,
wherein the threaded shank (<NUM>) comprises a first portion (<NUM>) extending from the head and a second portion (<NUM>) extending from the first portion, the first portion having a larger diameter than the second portion; and
wherein the head comprises a planar bearing surface (<NUM>) from which the first portion of the threaded shank extends,
wherein the first portion of the threaded shank comprises the thread (<NUM>) extending from the planar bearing surface of the head.