Patent Description:
The invention moreover relates to a method of preparing a connecting member for use in building assembly.

In the construction of buildings which may be subject to deflection (e.g., due to wind or seismic forces), it can be desirable to allow a degree of freedom of movement to reduce stress and possible fracture of connected parts. Specifically, for example, walls such as partition walls that are not intended to support vertical loads (i.e., "curtain walls") can be designed to allow deflection due to changes in live loads, such as deflection of the primary structure of the building (i.e., main supporting components to which secondary members are attached) from wind-induced or seismic stress loading and/or from changes in live or dead loading of the floor below or the ceiling above the curtain wall.

In view of these considerations, it would be desirable for improved vertical deflection connectors to allow relative vertical movement while exhibiting greater strength in restricting relative horizontal movement. It would further be desirable for such connectors to still be readily manufactured and installed. <CIT> describes a building assembly for connecting building elements, which has a breakaway washer which is broken away from a slot of one building element and permits the slot to move relative to fastener.

To that end, a connecting member of the type described in the opening paragraph, according to the invention, is characterised in that said bushing slidingly engages said first edge and said second edge of said elongated slot, while being coupled to the plate by a friction fit; in that the predetermined threshold value comprises a force magnitude required to overcome frictional engagement of the bushing with the plate, and in that said bushing maintains said friction fit with said plate.

In an embodiment the bushing is coupled to the plate at an initial position within each of the one or more slots by one or more tabs connected to the bushing and to the plate. The bushing can comprise one or more bulges protruding from at least one edge of the bushing towards an edge of a respective one of the one or more slots, each of the one or more bulges being associated with a depression formed in a surface of the bushing. In addition, the bushing can be movable relative to the plate within a respective one of the one or more slots upon application of a force exceeding a predetermined threshold value required to break the one or more tabs.

A method of preparing a connecting member for use in building assembly, according to the invention, comprises: forming a pair of substantially parallel slits in a metal blank; forming a depression between the substantially parallel slits; forming an elongated slot by removing material beginning from the substantially parallel slits for a predetermined length and width away from the depression; forming one or more dimples at or near one or more edges of the bushing, wherein forming the one or more dimples displaces a portion of the metal blank surrounding the respective one of the one or more dimples so that the substantially parallel slits are narrowed, wherein a portion of the metal blank surrounding each respective one of the one or more dimples is displaced across substantially an entire width of a respective one of the substantially parallel slits, wherein the portion of the metal blank contacts a portion of the metal blank on an opposite edge of a respective one of the substantially parallel slits and is coupled to the portion of the metal blank by friction; and forming a connector opening through the depression to form a bushing in the blank; wherein the bushing is coupled to the blank at an initial position within the elongated slot but is movable relative to the blank within the elongated slot upon application of a force exceeding a predetermined threshold value; and wherein the predetermined threshold value comprises a force magnitude required to overcome frictional engagement of the bushing with the plate.

In an embodiment of the connecting member for use in building assembly the substantially rigid plate has one or more openings formed therein, the one or more openings being configured for receiving a fastener. An area around the one or more openings is modified by work hardening to improve a strength of the area.

Although some of the aspects of the subject matter disclosed herein have been stated hereinabove, and which are achieved in whole or in part by the presently disclosed subject matter, other aspects will become evident as the description proceeds when taken in connection with the accompanying drawings as best described hereinbelow.

The features and advantages of the present subject matter will be more readily understood from the following detailed description which should be read in conjunction with the accompanying drawings that are given merely by way of explanatory and non-limiting example, and in which:.

The present subject matter provides systems, assemblies, and methods for connecting vertical steel wall studs to a building structure in a manner to permit relative vertical movement but prevent relative horizontal movement therebetween. In particular, in one aspect, the present subject matter provides a connecting member for use in building assembly (e.g., as a vertical deflection connector). As illustrated in <FIG>, for example, a connector assembly, generally designated <NUM>, can include a substantially rigid plate member <NUM> (e.g. a steel plate) having an elongated slot <NUM> formed therein, wherein the elongated slot includes opposed first and second edges <NUM> and <NUM> along its longest dimension. One or more additional fastener-receiving openings can also be provided in plate member <NUM>.

Another connecting member is shown in <FIG> in which a large connector plate, generally designated <NUM>, similarly comprises a substantially rigid plate member <NUM> and a flange <NUM> that extends from an edge of plate member <NUM>. Large connector plate <NUM> can have a plurality of elongated slots <NUM> formed therein.

Regardless of the particular configuration, the connector assemblies disclosed herein can each further include a bushing or washer element associated with each of the elongated slots formed in the substantially rigid plate members. Specifically, for example, referring again to the configuration shown in <FIG>, a bushing <NUM> can comprise a main body <NUM> through which a fastener center opening <NUM> can be provided. In some embodiments, main body <NUM> of bushing <NUM> can include a face <NUM>, which can itself include a depressed area <NUM> that is substantially concentric with the fastener center opening <NUM> and is angled from face <NUM> toward a center of fastener center opening <NUM>. In this arrangement, depressed area <NUM> is adapted to receive a fastener (not show here) and guide the fastener into fastener center opening <NUM>.

Bushing <NUM> can be configured to be coupled to plate member <NUM> at an initial position within slot <NUM>. In particular, in the configuration shown in <FIG>, bushing <NUM> is coupled with the plate by one or more tabs connected to bushing <NUM> and to plate member <NUM>. A detailed view of this configuration is shown in <FIG>. As shown in <FIG>, and <FIG>, bushing <NUM> can be connected to plate member <NUM> by a first tab <NUM> that projects away from a main body <NUM> of bushing <NUM> and connects bushing <NUM> to first edge <NUM> of slot <NUM>. Similarly, a second tab <NUM> can project away from main body <NUM> of bushing <NUM> and connect bushing <NUM> to second edge <NUM> of slot <NUM>. In the particular configurations shown in <FIG>, and <FIG>, for example, first tab <NUM> can connect a first corner of bushing <NUM> to first edge <NUM> of slot <NUM>, and second tab <NUM> can connect a diagonally opposing corner of bushing <NUM> to second edge <NUM> of slot <NUM>.

In accordance with the present invention, however, as shown in <FIG>, there may be no physical connection between bushing <NUM> and plate member <NUM>, but bushing <NUM> is sized to have a width that is substantially similar to a width of slot <NUM>. In this configuration, although no tabs or other physical connector actually joins bushing <NUM> to plate member <NUM>, bushing <NUM> is coupled to plate member <NUM> by friction.

In either configuration, bushing <NUM> can be substantially retained in slot <NUM> at a desired initial position (e.g., by first and second tabs <NUM> and <NUM> or by friction fit), which can allow an installer to position connector assembly <NUM> in a desired orientation with respect to other building elements to which connector assembly <NUM> will be coupled without having to separately align bushing <NUM>. As a result, installation of connector assembly <NUM> can be easier than using conventional connectors.

That being said, connector assembly <NUM> is configured such that bushing <NUM> is movable relative to plate member <NUM> within slot <NUM> upon application of a force exceeding a predetermined threshold value. For example, once connector assembly <NUM> is installed as part of a partition wall, it can be desirable to allow a degree of freedom of movement to reduce stress and possible fracture of connected parts as discussed above. In this regard, bushing <NUM> can be designed to be movable from its initial position as needed to allow such movement. Specifically, referring to the embodiments shown in <FIG>, and <FIG>, first and second tabs <NUM> and <NUM> can be designed to break when a force that exceeds a designed threshold value is exerted between plate member <NUM> and bushing <NUM>. Loads that are sufficient to cause bushing <NUM> to break away can vary based on the material thickness selected for a given application. In some embodiments, for example, bushing <NUM> is designed to break away under applied loads in the range of <NUM> pounds for thinner steels (e.g., t = <NUM>) and up to <NUM> pounds for heaver steels (e.g., t = <NUM>).

Similarly, referring to <FIG>, a bushing <NUM> can be designed to be movable relative to plate member <NUM> within slot <NUM> if a force exerted between plate member <NUM> and bushing <NUM> exceeds the frictional force that holds bushing <NUM> in its position in slot <NUM>. In any configuration, the force needed to cause bushing <NUM> to break away or otherwise become dislodged from its initial attached position is designed to not substantially affect the load-carrying capacity of the member it is supporting horizontally by applying an axial load through the attachment.

In some embodiments, to create a connector assembly <NUM> having one of the configurations discussed herein, plate member <NUM> and bushing <NUM> can be formed from a single piece of sheet stock. Specifically, for example, <FIG> illustrate exemplary steps in the formation of connector assembly <NUM>. Referring to <FIG>, first and second parallel slits <NUM> and <NUM> can be formed in a blank <NUM> to begin to define the portion of blank <NUM> that can serve as bushing <NUM>. Specifically, for example, as show in <FIG>, first and second slits <NUM> and <NUM> can be placed substantially medially in blank <NUM>, although those having skill in the art will recognize that the particular location of the slits can be selected to correspond to the desired eventual location of slot <NUM>.

The formation of connector assembly further include forming a depression <NUM> in an area substantially between first and second slits <NUM> and <NUM>. Depression <NUM> can further define the portion of blank <NUM> that can serve as bushing <NUM>, although a connector opening need not be formed at the same time. In addition, the forming of depression <NUM> can displace the material of blank <NUM> so that first and second slits <NUM> and <NUM> grow narrower along a center line <NUM> of depression <NUM>. As will be discussed below, this narrowing of first and second slits <NUM> and <NUM> can advantageously help retain bushing +<NUM> within slot <NUM>, even after first and second tabs <NUM> and <NUM> are broken.

With the portion of blank <NUM> that can serve as bushing <NUM> substantially defined by one or more of first and second slits <NUM> and <NUM> and/or depression <NUM>, slot <NUM> can be formed by removing material from blank <NUM> beginning from first and second slits <NUM> and <NUM> and proceeding for a predetermined length and width away from depression <NUM>. In some embodiments, this removal of material can be controlled such that first and second tabs <NUM> and <NUM> are left intact, wherein the portion of blank <NUM> having depression <NUM> is maintained in contact with the rest of blank <NUM>. Finally, fastener center opening <NUM> can be formed through depression <NUM>, whereby bushing <NUM> can thus be formed.

The above method can be applied to a blank having any of a variety of material thicknesses. That being said, in some embodiments, depending on the particular process by which material is removed from blank <NUM> (e.g., for the formation of first and second slits <NUM> and <NUM>), it can be difficult to achieve the desired sizes of one or more of the openings in blank <NUM> for greater thicknesses of blank <NUM>. Specifically, for example, where blank <NUM> comprises a sheet of steel or other metal, one way to form first and second slits <NUM> and <NUM> can be to use a metal punch. For increasing thicknesses of blank <NUM>, however, wider punches may be needed to penetrate the entire thickness of blank <NUM>. As noted above, though, it can be desirable for first and second slits <NUM> and <NUM> to be as narrow as possible to help retain bushing <NUM> within slot <NUM>. In addition, a narrow slit can help to reduce lateral motion of the connected building element (e.g., a wall stud) with respect to the anchorage point of connector assembly <NUM>.

Furthermore, in conventional building practices, special fasteners with oversized heads are often not considered desirable for economic and practical reasons, and thus a "standard" screw can be preferred to be used in coupling connector assembly <NUM> to an associated building element. Referring to <FIG>, for example, a fastener <NUM> having a head portion <NUM> can be coupled with bushing <NUM> (i.e., to connect connector assembly <NUM> to another building element). Fastener <NUM> is shown in phantom in <FIG> so that the underlying structure can be clearly seen. When bushing <NUM> is in an attached state with respect to plate member <NUM> as shown in <FIG>, bushing <NUM> can be substantially aligned at or near the center of slot <NUM>. In this arrangement, head <NUM> of fastener <NUM> extends over the entire width of slot <NUM> and overlaps with plate member <NUM> by a first overlap region 63a.

In situations in which bushing <NUM> breaks away from plate member <NUM>, however, the amount that head <NUM> overlaps plate member <NUM> can be reduced to a second overlap region 63b. To maintain secure coupling of fastener <NUM> with connector assembly <NUM>, this second overlap region 63b should be sufficiently large that loads that are expected to be imparted between head <NUM> and plate member <NUM> can be supported. In some embodiments, for example, second overlap region 63b is sized to be greater than the material thickness of plate member <NUM>. As noted above, because it can be preferable in many situations for fastener to be a standard size, controlling the size of second overlap region 63b thus involves controlling one or more of the width of slot <NUM>, the width of bushing <NUM>, or the width of first and second slits <NUM> and <NUM>. In some configurations, head <NUM> can often be only marginally larger than the width of slot <NUM>, and thus any substantial movement of bushing <NUM> to one side of slot <NUM> (See, e.g., <FIG>) can result in second overlap region 63b becoming too small to support the expected loads. As a result, it can be advantageous for first and second slits <NUM> and <NUM> to be as small as possible so that lateral motion of the connected building element does not allow one side of head <NUM> to disengage from plate member <NUM>.

To address this issue, the formation of bushing <NUM> can involve narrowing the width of first and second slits <NUM> and <NUM> after their formation. Specifically, for example, as discussed above, the formation of depression <NUM> between first and second slits <NUM> and <NUM> can cause material to be displaced into first and second slits <NUM> and <NUM>, thereby narrowing the distance between bushing <NUM> and first and second edges <NUM> and <NUM> of slot <NUM>. Alternatively or in addition, as shown in <FIG>, one or more depressions or dimples <NUM> can be formed at or near the edges of the portion of blank <NUM> that defines bushing <NUM> to further displace material into first and second slits <NUM> and <NUM>. In this way, one or more bulges <NUM> that protrude from at least one edge of bushing <NUM> into first and second slits <NUM> and <NUM> can be formed. In some embodiments, bulges <NUM> can extend substantially the entire distance across a respective one of first or second slits <NUM> or <NUM> such that bulges <NUM> contact a respective one of first or second edges <NUM> or <NUM> of slot <NUM>. For instance, such a configuration can create the frictional engagement discussed above with respect to the embodiment Illustrated in <FIG>.

In addition, dimples <NUM> can further serve to keep the head of an assembly screw away from contact with the surface of plate member <NUM>. Specifically, for example, as shown in <FIG>, the fastener <NUM> can be inserted such that head <NUM> bears on a convex portion of dimples <NUM>. This engagement with the protruding portion of dimples <NUM> can hold head <NUM> of fastener <NUM> away from the surface of plate member <NUM> by a small distance <NUM> (because the dimples are on the bushing, not the main clip surface). Alternatively or in addition, other features of connector assembly <NUM> can provide such an offset between the head of an assembly screw and the surface of plate member <NUM>. In some embodiments, for example, the edges of center opening <NUM> can be cupped either away or toward the screw head. In other embodiments, a recessed or protruding ring can be provided around center opening <NUM>, where the edge of center opening <NUM> is flat and a recessed or protruded ring is provided a small distance outside the diameter. In yet further embodiments, the edges of bushing <NUM> can be bent either away or toward the screw head.

Regardless of how this offset is produced, the resulting spacing allows fastener <NUM> to be physically tightened to join connector assembly <NUM> with a building element <NUM> without rigidly engaging fastener <NUM> with plate member <NUM> directly, which can thereby allow building element <NUM> to be movable with respect to plate member <NUM>. In contrast, in competitive products without such a configuration for a bushing, the fastener must be loosened after assembly to allow such movement. Such loosening is an extra installation step, and further makes it possible for the fastener to work its way loose over time.

Alternatively, the size of first and second slits <NUM> and <NUM> can be controlled at their formation by using a multi-step process. As illustrated in <FIG>, for example, rather than sizing first and second slits <NUM> and <NUM> based on the size of a metal punch that can penetrate through the entire thickness of blank <NUM>, a first and second indentation <NUM> and <NUM> can be made at or around the area in which first and second slits <NUM> and <NUM>, respectively, are desired. (See, e.g., <FIG>) Then, a second, narrower punch can be used to penetrate the now narrower thickness of blank <NUM> within first and second indentation <NUM> and <NUM>. In other words, the final width of first and second slits <NUM> and <NUM> can be determined by the size of the tooling needed to penetrate the narrowed thickness within first and second indentations <NUM> and <NUM> rather than what is needed to penetrate the entire thickness of blank <NUM>.

Furthermore, in addition to narrowing the width of first and second slits <NUM> and <NUM>, the process steps discussed above can also serve to strengthen the material of one or both of plate member <NUM> and/or bushing <NUM>. Specifically, the formation of one or more of depression <NUM>, dimples <NUM>, or first and second indentations <NUM> and <NUM> can plastically deform the material surrounding these features at or near the edges of plate member <NUM> and/or bushing <NUM>. Those having skill in the art will recognize that such plastic deformation can improve the material strength of these elements at those locations through work hardening.

Accordingly, this improvement in the material strength can be applied to the formation of connector assembly <NUM> in areas other than those involving the formation of first and second slits <NUM> and <NUM>. Specifically, for example, <FIG> illustrates an embodiment in which substantially the entireties of first edge <NUM> and second edge <NUM> of slot <NUM> are deformed. Because first and second edges <NUM> and <NUM> are those portions of plate member <NUM> that engage bushing <NUM> when lateral loads are applied between the connected building elements, improving the strength of first and second edges <NUM> and <NUM> can correspondingly improve the strength of connector assembly <NUM> when exposed to such conditions. In addition, those having skill in the art will appreciate that such work hardening of other edges and interfaces of connector assembly <NUM> can provide further benefits to the strength of connector assembly <NUM>.

Claim 1:
A connecting member (<NUM>, <NUM>) for use in building assembly comprising:
a substantially rigid plate (<NUM>, <NUM>) having one or more elongated slots (<NUM>) formed therein, wherein at least one of the one or more elongated slots (<NUM>) comprises a first edge (<NUM>) and a second edge (<NUM>) along a longest dimension of a respective one of the one or more slots (<NUM>); and
a bushing (<NUM>) coupled to the plate at an initial position within each of the one or more slots (<NUM>) but movable relative to the plate (<NUM>, <NUM>) within a respective one of the one or more slots (<NUM>) upon application of a force exceeding a predetermined threshold value;
wherein the bushing (<NUM>) has a width that is substantially similar to a width between the first edge (<NUM>) and the second edge (<NUM>) of the respective one of the one or more slots (<NUM>) such that the bushing (<NUM>) is coupled to the plate (<NUM>, <NUM>) by a friction fit; and
wherein the predetermined threshold value comprises a force magnitude required to overcome frictional engagement of the bushing (<NUM>) with the plate (<NUM>, <NUM>).