In the context of cavity wall structures for construction, the walls are typically formed of two wythes. These may both be of masonry, the wythes being spaced apart to form a vertical space or cavity therebetween. Alternatively, it may have an outer masonry wall such as of bricks, with an inner building wall of wood, wallboard, concrete, concrete masonry units (“CMU”), tile, or similar commonly used interior wythe materials.
It has long been common in the field of cavity wall construction to use masonry anchors or other similar fastening mechanisms in order to anchor the two wythes to one another, thereby forming a conjoined, singular wall structure. Such anchors are typically fabricated from metal, such as steel, and comprise two elements attached, either in manufacture or upon installation, one element being a masonry reinforcement and the other at least one bracket.
Typically, the masonry reinforcement comprises a pair of generally parallel, elongate arms connected by a series of transverse bars. Most commonly, the masonry reinforcement is configured in either a ladder-type configuration with the transverse bars extending perpendicular to the elongate arms, or a truss-type configuration, wherein the transverse bars form a series of triangles with the elongate arms. In installation, the masonry reinforcement is positioned on a mortar joint within the inner wythe and acts as the support structure of the anchoring system. Multiple anchoring systems may be installed on several mortar joints within a particular cavity wall.
Extending externally laterally from the masonry reinforcement are a plurality of spaced-apart brackets. The brackets are typically welded to the inboard (closer the cavity) elongate arm of the masonry reinforcement. That weld may be at each node formed at the junction of an elongate arm and the transverse bar.
Multiple configurations of the brackets are known in the art. For example, a common configuration comprises two “eyes” at the terminal ends of a single U-shaped bracket, as shown in FIG. 1. The eyes receive a fastening member, such as a wall tie, that is affixed to the outer wythe. Typically, such U-shaped brackets are welded to the top of the masonry reinforcement, providing three welding points between the masonry reinforcement and bracket, but placing the masonry reinforcement and bracket on two different horizontal planes. While this configuration generally ensures a strong connection between the masonry reinforcement and bracket, while maintaining a generally horizontal configuration of the bracket relative the mortar joint, the added thickness within the mortar joint may decrease the strength of the wall structure as less mortar may occupy the thickness of the joint.
A similar prior art U-shaped bracket is depicted in U.S. Pat. No. 6,735,915, wherein the base of the “U” is concave, thereby defining two weld points between the masonry reinforcement and bracket. This eliminates the added thickness of the anchoring system when the bracket is welded on top of the masonry reinforcement, as in other prior art systems.
The eyes of the bracket must also provide sufficient strength to withstand tensile stress tending to pull the two wythes apart. Currently, it is known in the art to provide a partially closed eye at the two terminal ends of the U-shaped bracket. In manufacture, such brackets are formed by first bending a single wire to form the U-shaped portion of the bracket, and then performing the secondary operation to bend the two ends of the wire into the semi-circular eye, either prior to or during installation.
The stem of the bracket, i.e. the legs of the “U”, must also resist compressive stress.
The Applicant has perceived a need for an improved masonry anchor, and how to accomplish that.
The drawings are for the purpose of illustrating example embodiments and may not be drawn to scale. The inventions are not limited to the arrangements and instrumentalities shown in the drawings.