Field of the Invention
The present invention relates to a method and apparatus for tying down and anchoring a bulldog structure such as a mobile home, thereby providing improved stability and rigidity.
Background of the Invention
Mobile homes and like structures such as temporary or portable buildings are widely used because of their low cost and ability to be moved from one location to another. An inherent downfall of mobile homes is their structural instability because they are not constructed upon nor fixed to a foundation as are permanent structures, but are merely placed on blocks or jacks. Consequently, the aforementioned structures are susceptible to damage or destruction from high speed winds, surface vibrations, movement of occupants, or other similar forces.
In an effort to add structural stability to mobile homes, several types of tie down and anchoring apparatuses have evolved. U.S. Pat. No. 3,724,151 to Kaywood et al. discloses a mobile home anchoring apparatus having one end clamped to the mobile home underframe and the opposite end embedded in a concrete base. As Kaywood provides a means for linearly adjusting the tension of the anchoring apparatus in the form of a turnbuckle and chain. Lopes, U.S. Pat. No. 4,272,933, discloses a mobile home anchor which is similar to Kaywood but which eliminates the necessity of welding the loops of the eye bolts closed in the Kaywood structure without sacrificing strength. This is achieved by means of a first clevis bolted to the base and a second clevis attached upwardly to the legs of the base clevis.
However, the anchoring type devices such as disclosed in Kaywood and Lopes only attached to the under frame of the mobile homes and did not add any stability to the vertical walls or roof of the structure. Moreover, the mobile homes must have an under frame compatible with the clamping means disclosed in Kaywood and Lopes for those anchors to be properly attached to the frame.
Alternatively, tie down type devices are disclosed in U.S. Pat. No. 3,335,531 to Grimelli et al. and U.S. Pat. No. 3,726,054 to Anderson et al. Grimelli discloses an exteriorly mounted tie down system having a cross rod connected at each end to corner brackets positioned on opposite sides of the mobile home and a brace rod extends downwardly from each bracket and attaches at its lower end to hooks embedded in a concrete base. Additionally, Grimelli teaches the connection of the mobile home underframe to the hooks by means of a securing rod. Similarly, Anderson discloses an apparatus having a continuous cable positioned over the mobile home and anchored at each end on opposite sides of the mobile home.
The tie down type apparatus of the types disclosed in Grimelli and Anderson add stability to the vertical walls and roof of mobile homes but must be mounted on the exterior of the mobile homes.
Accordingly, it can be seen that it would be desirable to provide an apparatus for stabilizing and securing structures such as mobile homes which offers stability to both the underframe and vertical side members of the mobile home while remaining hidden from site.
Summary of the Invention
Briefly described, the present invention comprises a method and apparatus for securing and tying down building structures such as mobile homes to the earth or foundation upon which they rest. The apparatus for tying down mobile homes includes an elongated threaded rod assembly which is anchored at its lower end to a concrete base and extends upwardly, first through the floor joist and then up to the roof structure where it is connected to the rafters or other roof structures.
The elongated threaded rod assembly is comprised of a lower and a upper rod segment. The lower rod segment has its lower end embedded in a concrete base and its upper end extending through the floor joist of the mobile home and is internally threaded into the bottom of a hold-down block. This portion of the rod assembly anchors the mobile home by its frame, securing it to the foundation upon which it rests. A feature of the present invention is that the lower rod segment may function alone as an anchoring system without installing the upper rod segment, thereby offering great versatility.
The upper segment of the rod assembly has its lower end threaded into the top of the hold-down block and its upper end extending upwardly through openings in a roof beam and bracket. The bracket is an elongated member which extends over the upper surfaces of the rafters and roof beams. An internally threaded lock block is screwed onto the end of the upper rod segment extending past the roof beam and bracket. This portion of the rod system adds stability to the vertical walls and roof structure of a mobile home without having to exteriorly mount a system which would hamper the visual appeal of the structure and eventually weaken over time from the corrosive effect of nature. The present invention avoids these inadequacies by mounting the rod assembly in the interior space between the exterior and interior walls of the mobile home.
Accordingly, it is an object of the present invention to provide an improved apparatus for tying down and securing portable buildings such as mobile homes.
Another object of the present invention is to provide a tie down apparatus which does not detract from aesthetical value of the structure which it secures.
Another object of the present invention is to provide a tie down apparatus which is versatile in operation and which has improved securing capabilities, and is economical and easy to install.
Other objects, features and advantages of the present invention that can be understood from a review of the following specification when taken in conjunction with the accompanying drawings.
Brief Description of the Drawings
FIG. 1 is a perspective cut away view of the tie down apparatus for securing portable buildings such as a mobile home.
FIG. 2 side elevational view of the tie down apparatus for securing portable buildings such as mobile homes.
FIG. 3 is a detail of the base of the anchor structure.
FIG. 4 is a detail of the hold down block.
FIG. 5 is an exploded perspective view of the tie down apparatus, substantially illustrating the overlapping segments of the bracket and rafters.
Detailed Description of the Preferred Embodiment
Referring now in greater detail to the drawings, FIG. 1 illustrates a tie down apparatus 10 for anchoring a building structure 12, such as a mobile home or other portable building not anchored to the ground. The building structure typically has a floor structure mounted on a supporting frame which is suspended above the ground surface by concrete blocks, etc., and a roof structure suspended by studs, etc., over the floor structure. Tie down apparatus 10 includes an elongated threaded rod assembly 16 disposed in the space defined by an exterior facade 18 and an interior facade 20 of the building structure and an anchoring means such as concrete base 14 which usually is cast in place, in the ground and covered with soil, etc. The rod assembly extends through a floor joist 22 between wall studs 17 and upwardly to the roof beam 26. The elongated threaded rod assembly 16 includes a lower threaded rod 28 and upper threaded rod 30, connected together in end-to-end relationship by hold-down block 32. Lower and upper threaded roads, 28 and 30 respectively, are preferably made of steel or the equivalent.
As FIG. 2 illustrates, lower rod 28 is threaded at both ends, the lower end 34 being threaded into an anchor connection means such as base plate 36. The base plate and lower portion of lower threaded rod 28 are embedded in concrete base 14. Concrete base 14 may be disposed at ground level, or alternatively, submerged below the earth's surface and covered with soil, etc. as shown in detail in FIG. 3. Lower threaded rod 28 extends upwardly from concrete base 14, through opening in the floor joist 22 and the floor beam 41. A bolt 29 threaded onto lower threaded rod 28 and spacing means, such as washer 27, are disposed adjacent to the bottom surface of floor joist 22. The upper end 42 of lower threaded rod 28 extending above floor beam 41 is threaded into a floor connector means such as the hold-down block 32.
As illustrated in FIG. 4, the hold down block 32 has internally threaded bores, threaded bore 41 facing downwardly for receiving the upper end 42 of lower threaded rod 28, and threaded bore 45 facing upwardly for receiving the lower end 43 of upper threaded rod 30. Threaded bores 41 and 45 sham the same central axis, though in an alternative embodiment the threaded bores 41 and 45 can be disposed side by side, having parallel axes.
The upper rod 30 is threaded at both ends, the lower end 43 being threaded into hold-down block 32 and the upper end extends upwardly through roof beam 26 to a roof connection means such as elongated bracket 40. The portion of upper rod 30 extending past roof beam 26 and elongated bracket 40 is threaded into a lock block 46. As illustrated in FIG. 2, a bolt 35 threaded onto upper threaded rod 30 and a spacing means, such as washer 31, are disposed adjacent the bottom surface of roof beam 26.
FIG. 5 shows the overlapping engagement of elongated bracket 40 and the rafters 24. Bracket 40 has a plurality of outwardly projecting protrusions 50 which are spaced apart and sized and shaped so as to fit over rafters 24 with connecting spans 52 therebetween. When the bracket 40 has its protrusions fitted on rafters 24, the lower spans 52 between the protrusions lie flush against the upper surface of roof beam 26, and are fastened thereto by conventional means such as nails 54. The upper end 44 of upper threaded rod 30 protrudes through an opening in bracket 40 and is threaded into lock block 46.
It can be understood from the description above and the accompanying illustrations that the tie down functions as a hold down to resist the lifting forces created by negative air pressure resulting from wind traveling across the roof of the building structure. Additionally, the tie down functions a hold down to resist lateral movement at the base of the building structure.
If the mobile home or other building structure 12 has an obstruction, such as a window, electrical wiring, or plumbing, which is not suitable for the installation of the upper rod 30, the upper rod and its brackets 40 can be eliminated and the lower rod 28 may be used with the hold down block 32 and base 14 to hold down and secure the lower frame of the building structure 12.
Although the invention has been shown in a preferred form thereof, it should be understood that numerous changes, modifications, additions and deletions may be made thereto without departure from the spirit and scope of the invention as set forth in the following claims.