Abstract:
A tension strap connector assembly for use in a stabilizing foundation system for a manufactured home supported by at least one flanged beam. The tension strap connector assembly is adapted at a first end so as to hook around and latch about a flange of the manufactured home support beam. At a second end, the tension strap connector has a strap slot adapted to receive a tension strap of the stabilizing foundation system, wherein the tension strap is attached at one end to a ground anchor. The tension strap connector provides a means for altering the orientation of the tension strap relative to the hook portion so that the tension strap can be arranged in non-perpendicular orientations with respect to the manufactured home without creating a torsional stress concentration within the tension strap.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This is a continuation-in-part of U.S. Utility patent application Ser. No. 09/282,854, filed Mar. 31, 1999, now U.S. Pat. No. 6,176,056, which is a continuation-in-part of U.S. Utility patent application Ser. No. 09/195,468, filed Nov. 18, 1998, now U.S. Pat. No. 5,983,573. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to a strap connector assembly for use in a manufactured home stabilizing foundation system using tension straps. More particularly, the invention relates to a strap connector assembly which does not create harmful stress concentrations within the tie down straps when the straps are arranged in non-perpendicular orientations with respect to the manufactured home, and which positively latches to the manufactured home frame. 
     BACKGROUND OF THE INVENTION 
     Manufactured homes, such as mobile homes, trailers, prefabricated homes, and the like are manufactured at a central manufacturing site and, upon completion, are moved to a location where they are to be occupied. Because these homes are designed to be easily transported from one site to another, they are not built on permanent foundations but, rather, typically are placed on piers such as concrete blocks, pilings, or stabilizing jacks. Normally, the piers directly support the frame of the manufactured home which typically comprises two or more support beams, such as steel I-beams, to which the home is fixedly secured. 
     If the manufactured home is not anchored securely in position on its piers, the home can be shifted by strong winds or earth tremors which can cause the home to be forced from its foundation. Due to this risk, various types of stabilizing systems have been used for stabilizing the manufactured homes on their piers in order to keep the homes from shifting in response to wind and/or seismic forces. In one particularly effective system, a plurality of tension straps are used to tether the manufactured home to the ground. In these systems, the tension straps typically extend perpendicularly outwardly from incremental positions along the length of the manufactured home. Usually, the tension straps extend downwardly from the support beams of the manufactured home frame to ground anchors that are deeply embedded into the soil. Often, the tension straps are securely connected to the beams with strap connector assemblies that latch onto the support beams. Normally, a strap connector assembly comprise a metal clamp member that includes a hook which securely grips an upper flange of the support beam. The tension straps usually are threaded through a strap slot formed in the clamp member. These strap slots normally are configured so as to be parallel to the hook and the longitudinal direction of the manufactured home, such that the tension straps can be positioned substantially perpendicularly to the longitudinal direction of the manufactured home. 
     Although functioning adequately under most circumstances, conventional strap connector assemblies present several drawbacks. Most importantly, these strap connector assemblies do not account for longitudinal shifting of the manufactured home due to wind or seismic forces. When a manufactured home shifts under the influence of such forces, the longitudinal position of the strap connector assemblies, and their respective strap slots, likewise shift in the same longitudinal direction. Because the ground attachment points of the tension straps are fixed by the anchors, the tension straps cannot similarly shift longitudinally, thus causing the orientation of the tension straps to become diagonal with respect to the longitudinal direction of the I-beam of the manufactured home. In that the strap slots of the strap connector assembly cannot reorient themselves to accommodate the diagonal orientations of the straps, torsional stresses are concentrated on the straps at the point where the straps connect to the strap connector assemblies. Such stress concentrations can similarly occur in situations in which the tension straps are improperly installed, e.g. In a non-perpendicular orientation relative to the manufactured home. Large stresses can cause failure of one or more of the tension straps, therefore in order to securely fix the home to the foundation it is important to insure that there are no large stresses in the tension straps. Even if torsional stresses do not cause a failure of a strap, torsional stresses can violate the standards stipulated by the United States Department of Housing and Urban Development (HUD) regarding systems for stabilizing foundations. In addition, a shift of the ground anchor in the longitudinal direction coupled with the tension force in the tension strap induces a torque on the strap connector assembly. Such a torque can cause the strap connector assembly to orientate itself so as to relieve the stress, but in doing so the hook of the strap connector assembly is no longer properly secured to the I-beam. 
     Sometimes it is necessary or convenient to position the ground anchors  20  such that the tension straps  24  are not orientated perpendicular to the longitudinal direction of the I-beam of the home. For example, there may be an obstruction such as an underground pipe or wires, or a large stone, which can be surmounted if the tension strap could be positioned in a non-perpendicular orientation. From the above, it can be appreciated that it would be desirable to have a strap connector assembly which does not create harmful stress concentrations on the tension strap when the strap is orientated in a non-perpendicular orientation with respect to the home. It would also be desirable to have a strap connector assembly that is easily attached to the home within the standards set by HUD, such that when the strap is inadvertently in a non-perpendicular orientation there are no harmful stresses and the stabilized foundation remains in compliance with HUD standards. 
     U.S. Pat. No. 5,983,573, discloses a device for relieving torsional stresses in a tension strap used in a stabilizing foundation system. The disclosed device includes a clamp member for hooking onto an I-beam of the home and a swivel member coupled to the clamp member by a bolt or pin. While the product of the &#39;573 patent functions properly as intended, this two piece product with its connector bolt is more expensive to produce than a one piece product and requires some adjustment at the site of the manufactured home during installation. The present invention, described in more detail herein below, seeks to overcome these problems, while addressing the problem of relieving torsional stress in the tension strap. 
     SUMMARY OF THE INVENTION 
     Briefly described, the present invention relates to a tension strap connector assembly for use in a stabilizing foundation system for a manufactured home which comprises a frame including at least one flanged support beam. The tension strap connector assembly includes a hook portion adapted to latch about a flange of the manufactured home support beam, a strap slot adapted to receive a tension strap of the stabilizing foundation system, and the tension strap which has one end extending through the strap slot. The strap slot is shaped for altering the orientation of the tension strap relative to the hook portion so that the tension strap can be arranged in non-perpendicular orientations with respect to the lengths of the support beams of the manufactured home without once nor eating torsional stresses within the tension strap. 
     The strap connector assembly includes a connector plate and a rocket bearing. The connector plate includes a body portion having first and second ends, with a hook portion at the first end and strap mounting extension at the second end. The strap mounting extension extends from the body portion and has an opening extending therethrough. The opening has a convex edge distal from the first end of the body portion and is adapted to receive both the rocker bearing and a tension strap. The rocker bearing is formed from a flat strap into a U-shaped body having a pair of legs joined at one end by a concave bend having a concave inner surface and an outer convex surface. The outer convex surface of the rocker bearing provides a curved, rounded bearing surface for engagement by the tension strap. The inner concave surface of the rocker bearing is rectilinear along the transverse length of the rocker bearing, and is adapted to fit loosely around the convex edge of the opening in the connector plate. Due to the rectilinear transverse length of the concave inner bearing surface of the rocker bearing which is matched with and bears against the curvature of the convex edge of the opening in the connector plate, there is only one transverse point of contact between the concave bearing surface of the rocker bearing and the convex edge of the connector plate. This point of contact shifts as the rocker bearing rocks on the convex edge; similar to how the point of contact between a rocking chair and a floor shifts as the chair is rocked. The load of the tension strap is communicated to the rocker bearing, and from the rocker bearing to the connector plate at the movable point of contact. 
     An advantage of having the rocker bearing rock on the convex edge, instead of having a pivotably mounted swivel member, is that the rocker bearing and the connector plate do not become frozen together. Even when there is rust formed between the rocker bearing and the connector plate, the rust bond is easily broken because there is only one transverse point of contact between the connector plate and the rocker bearing. Whereas, in a device which uses a pin to couple two pieces together, the entire circumference of the pin can become bonded by rust to the coupled pieces, thereby locking the device into one orientation. Also, the connector plate is formed in one piece instead of multiple pieces pivotally connected by a bolt, or other conventional coupling connectors. In addition, the one piece structure is stronger and less expensive to manufacture. 
     The objects, features, and advantages of this invention will become apparent upon reading the following specification, when taken in conjunction with the accompanying drawings. It is intended that all such additional features and advantages be included therein with the scope of the present invention, as defined by the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views. 
     FIG. 1 is a partial end view a manufactured home and manufactured home stabilizing foundation system which includes a strap connector assembly and a tension strap, constructed in accordance with the present invention. 
     FIG. 2 is an expanded perspective view of the strap connector assembly and a looped end of a tension strap shown in FIG.  1 . 
     FIG. 3 is a cross sectional side view of the strap connector assembly and a looped end of a tension strap. 
     FIG. 4 is a top view of the strap connector assembly with the tension strap oriented perpendicular, to the length of an I-beam to which a home is fixedly secured, and a cross sectional view of the rocker bearing aligned in a plane perpendicular to the length of the I-beam. 
     FIG. 5 is a top view of the strap connector assembly, similar to FIG. 4, but showing the tension strap and rocker bearing oriented at an angle from the plane perpendicular to the length of the I-beam. 
    
    
     DETAILED DESCRIPTION 
     Referring now in more detail to the drawings, in which like reference numerals indicate corresponding parts throughout the several views, FIG. 1 illustrates a tension strap connector assembly  10  as used in a stabilizing foundation system  12  for a manufactured home  14 . 
     As shown in FIG. 1, the manufactured home  14  is supported by a frame which includes at least two parallel support beams  16  and a plurality of support piers  18  aligned along the lengths of the beams  16 . Normally, the support beams  16  are formed as steel I-beams and the support piers  18  comprise concrete blocks. The stabilizing foundation system  12  typically comprises a plurality of ground anchors  20 , each including a tension head  22  secured to the upper end of a shaft  23  which facilitates attachment of a tension strap  24  to the anchor. The tension straps  24  each are wound in a spiral at its lower end to a bifurcated bolt  25  in the tension head and extend upwardly from its ground anchor  20  to connect to the I-beam  16  of a manufactured home  14 . As indicated in FIG. 1, the tension strap  26  can extend from the ground anchor upwardly about the outer periphery of the manufactured home  14  or, in addition or alternatively, a tension strap  24  can connect to the support beams  16  of the manufactured home frame. In the latter case, connection is facilitated by the tension strap connector assembly  10 . 
     FIGS. 2 through 5 illustrate the tension strap connector assembly  10  in more detail. The strap connector assembly  10  generally includes a connector plate  27  and a rocker bearing  28 . The connector plate  27  includes a substantially planar body portion  30  having front end  32  and rear end  34 . A hook portion  36  extends obliquely at an acute angle from the front end  32  of the body portion  30 . A strap mounting extension  38  extends obliquely at an obtuse angle from the rear end  34  of the body portion  30 . The strap mounting extension  38  has a top side  40  and a bottom side  42 . Like the body portion  30 , the hook portion  36  and the strap mounting extension  38  typically are substantially planar in shape. As shown in FIG. 3, the strap mounting extension  38  is contained in a plane that forms an approximately 45° angle with the plane that contains the body portion  30 . The strap mounting extension  38  includes an opening  44  for receiving rocker bearing  28  and tension strap  24  shown in FIG.  3 . Opening  44  is formed such that an edge  46  is convex shaped, the convex edge  46  is distal from the first end  32  of connector plate  27 . 
     Rocker bearing  28 , illustrated in FIGS. 2 and 3, is formed from flat steel strap material and is formed into a U-shape and includes a curved end  48  and first leg  50  and second leg  52  extending therefrom. The curved end  48  has a convex outer surface  49  and a concave inner surface  47 . First and second legs  50  and  52  are essentially parallel and adapted to fit loosely around the convex edge  46  of the opening  44  of the connector plate  27  and straddle top and bottom sides  40  and  42  of the strap mounting extension  38 . 
     FIG. 3 illustrates rocker bearing  28  in its operational position with a portion of tension strap  24  inserted longitudinally through opening  44  and folded back over and connected to itself to form a looped end. Tension strap end  54  of tension strap  24  is affixed to portion  56  of tension strap  24  by connector means  53  including welding, bonding, riveting and/or using a nut and bolt, or other conventional connectors. In this manner tension strap  24  is fixedly looped around rocker bearing  28  and connector plate  27 , and rocker bearing  28  is prevented from becoming dislodged from between the strap and the connector plate. 
     Typically, prior art tension straps are received by openings having right angled edges, and consequently when a tension strap is bent around such an edge and tension is applied to the strap a sharp bend radius is produced in the tension strap. Tension straps are more likely to become fatigued and break at sharp radii bends than at bends with larger radii. Therefore, it is desirable to fixedly couple tension strap  24  to strap connector assembly  10  such that there are no sharp radii bends in tension strap  24 . Curved end  48  of rocker bearing  28  provides an inner concave surface  47  for bearing against the edge  46  of the opening  44  of the connector plate  27  and an outer convex surface  49  for engagement by the tension strap, thereby providing an essentially smooth rounded external surface around which tension strap  24  is bent. Because tension strap  24  conforms to curved end  48  of the rocker bearing  28 , the load from tension strap  24  is communicated to rocker bearing  28  over the entire convex outer surface  49  of curved end  48 , instead of being concentrated in a few sharp points of contact. 
     When strap connector assembly  10  is properly affixed to I-beam  16  of premanufactured home  18 , as illustrated in FIG. 3, connector plate  27  is oriented essentially perpendicular to the length of I-beam  16 ; body portion  30  lies atop the upper flange  58  of the I-beam  16  with hook portion  36  latched about top flange  58 . In this configuration, front end  32  of connector plate  27  is essentially parallel to the longitudinal direction of I-beam  16  and body portion  30  of connector plate  27  is configured to lie atop the entire width of I-beam  16 , such that second end  34  of the body portion  30  extends beyond or abuts the edge of the upper flange  58  of the I-beam  16 . Strap mounting extension  38  extends from second end  34  generally diagonally there down and out. 
     Referring now to FIGS. 4 and 5, strap connector assembly  10  is shown from above with a partial cross sectional view of rocker bearing  28  and tension strap  24 , with the cross sectional view taken along line I—I in FIG.  3 . Strap connector assembly  10  is properly affixed to I-beam  16  (not shown in FIGS. 4 and 5) as described herein above. In FIG. 4 rocker bearing  28  is orientated such that strap  24  extends from connector plate  27  in a plane essentially perpendicular to first end  32  of connector plate  27 . FIG. 5 illustrates the orientation of rocker bearing  28  responsive to tension strap  24  being orientated at an non-perpendicular angle to front end  32 . 
     To secure I-beam  16  to stabilized foundation  18  tension strap  24  is attached at one end to anchor  20  and at its other end looped through the opening  44  of the connector plate and around rocker bearing  28 . Tension in tension strap  24  pulls rocker bearing  28  onto convex edge  46 , such that concave inner surface  47  of curved end  48  between first leg  50  and second leg  52  bears against convex edge  46 . As illustrated in FIGS. 4 and 5 the concave inner surface  47  of the curved end  48  is rectilinear in the direction transverse to the curvature of rocker bearing  28 , and curved end  48  is in contact with convex edge  46  at only one transverse point, load bearing contact  60 . At the point of contact, the load from the tension in tension strap  24  is communicated through rocker bearing  28  to connector plate  27 . The tensional force in tension strap  24  can be decomposed into in a horizontal component of force and a vertical component of force. The horizontal component of the tension force pulls the connector plate, such that the hook portion  36  is latched around flange  58  of I-beam  16 . The vertical component of the tensional force pulls down on connector plate  27  such that body portion  30  is held against I-beam  16 . When the tension is directed in a plane perpendicular to front end  32  of strap connector assembly  10 , rocker bearing  28  bears on the vertex of convex edge  46 , as illustrated in FIG.  4 . Because rocker bearing  28  and convex edge  46  are in contact at only one transverse point, rocker bearing  28  can rock on convex edge  46 , and therefore the transverse point of contact can be shifted anywhere along the convex edge  46 . 
     FIG. 5 illustrates the orientation of rocker bearing  28  when strap  24  is angled non-perpendicular to front end  32  of connector plate  27 ; such an orientation occurs when anchor  20  is displaced along the longitudinal direction of I-beam  16  relative to strap connector  10 . The non-perpendicular orientation of tension strap  24  can be the result of longitudinal shifting of the mobile home or the result of improper positioning of the anchor during installation. In either case, the relative displacement of anchor  20  coupled with the tension force in tension strap  24  induces a torque on rocker bearing  28 . In response to the torque, the load-bearing contact  60  shifts along the convex edge  46  as rocker bearing  28  changes orientation so as to negate the applied torque. Therefore, torsional stresses in tension strap  24  are substantially reduced, and a possible source of strap failure is reduced. 
     While preferred embodiments of the invention have been disclosed in detail in the foregoing description and drawings, it will be understood by those skilled in the art that variations and modifications thereof can be made without departing from the spirit and scope of the invention as set forth in the following claims. For example, tension strap  24  can be affixed to rocker bearing  28 . All such variations and modifications are intended to be included herein within the scope of the present invention, as set forth in the following claims.