Fences – Metallic
Reexamination Certificate
2000-05-24
2002-12-10
Browne, Lynne H. (Department: 3679)
Fences
Metallic
C256S065080, C403S205000, C403S231000
Reexamination Certificate
active
06491286
ABSTRACT:
BACKGROUND
1. The Field of the Invention
This invention relates to fencing, and more particularly, to novel methods and apparatus for framing sheathed gate structures such as vinyl gates.
2. The Background Art
Gates have existed as long as fences have. Fences have existed substantially as long as the concept of private property has existed. With the advent of new materials and the decorative abilities of plastics, plastic fencing, such as vinyl, and its supporting fencing components have become popular.
Gates have limited ability to suspend from gateposts. Moreover, cantilevered structures need some type of rigid structural support. In addition, vinyl fencing systems do not typically support rigid corners. For example, stresses at corners of gates exceed the loads supportable by vinyl structures.
For many purposes, vinyl fencing is adequately strong, durable, weather resistant, structurally supportive, and the like. However, gates are moving members that are supported from a single side or end. Accordingly, substantial structural integrity is required to a greater degree in a gate than may be required from other fencing components. Moreover, since a gate may be effectively cantilevered, stresses may be substantially higher in portions of a gate, than they would be if merely supporting the weight of a fence structure directly thereabove.
Accordingly, in certain gate systems, a gate itself may be formed of a metal. Alternatively, the gate may be structurally framed of metal, covered with electrostatic powder coating, paint, or sheaths of vinyl material. Metal frames exhibit two serious difficulties, among others. Rigid frames are large, bulky to transport, heavy to handle, and problematic to inventory in a large number of size options.
Attempts to remedy the limitations of solid, prefabricated gates or gate frames, result in welds at corners of steel structures. The welds are subjected to substantial stress from twisting under windloads, slamming, eccentric loading, and various other forces incident to operation of the gate. Thus, assembled, metal, gate frames or gates lack rigidity, or else they tend to fracture at points assigned the responsibility for rigidity.
Gates enjoy another peculiarity. Since gates tend to cover a space or opening having a substantially rectangular aspect, gates are structurally not naturally rigid. That is, any four member structure (quadrilateral) is fundamentally unstable. Making a gate from a plastic serving as structural members is often untenable. Thus, a plastic fence may still require a metal gate.
Torsional rigidity is difficult in a gate, moreover, because a gate structure is typically dominated by two dimensions, a vertical dimension and a horizontal dimension, in which the gate extends. The transverse direction through the gate is typically orders of magnitude less than that of the longitudinal (vertical) or lateral (horizontal) dimension along the expanse of the gate.
Accordingly, forces in a transverse direction (through the gate) typically tend to twist one corner about the next two proximate corners. Thus, gate structures often break near the corners thereof due to torsion from loading transversely through the gate against any one of the corners.
In order to obtain maximum strength and stiffness, a tubular member represents a nearly optimal configuration. Rectangular tubular cross sections and circular tubular cross sections provide very stiff structures. Tubular members may be welded and braced to form comparatively strong gates. In order to stabilize the longitudinal and lateral dimensions of a gate structure, a diagonal brace or support may extend from an upper corner (inside) near a hinging mechanism down to an opposite lower corner (outside) that swings as the gate opens. Thus, a comparatively unobtrusive but strong gate support may greatly benefit the rectangular structure.
However, the overall lifetime of a gate structure begins with production of stock materials from which to construct a gate. Many materials are long. That is, one may define an aspect ratio as a relationship of one linear dimension to another linear dimension (typically in a direction orthogonal to the first). An aspect ratio may be thought of as a ratio of the relative aspects of the two dimensions. Gates may have an aspect ratio near unity for their longitudinal and lateral and longitudinal dimensions, but much smaller or greater for others (e.g. transverse: lateral longitudinal: transverse).
When materials are shipped from a source of raw stocks or from a manufacturer of gate hardware to a reseller or customer, total shipping weight is important. Moreover, total shipping volume is important. Shipping costs may increase with excess weight or with excess volume (cubic feet). Thus, a load may “gross out” a hauling vehicle if the weight reaches the maximum vehicle weight permissible. A load may “cube out” a hauling vehicle if the volume of packaging containing goods fills the entire available volume. Ideally, a load grosses out and cubes out a hauling vehicle at about the same point (same number of products). A vehicle grossed out could carry more volume if the volume were not so heavy. A vehicle that is cubed out could haul more weight if the weight did not fill up or require so much volume.
As this applies to gate hardware, maximum structural reliability is required at a minimum weight and minimum shipping volume. Traditionally, gate frames have been manufactured as rigid structures fully assembled. Often, gate frames are welded structures for supporting other gate materials, such as slats, pickets, panels, and the like. As a practical matter, tubular steel may be formed into rectangular structures to serve as gate frames. Whereas other gate materials may be shipped as long stocks, gates become large in two dimensions. Meanwhile, the tubular steels available for welding are often very heavy, comparatively, with respect to other gate materials (especially plastics such as vinyl).
Metallic gates and metallic gate frames have heretofore been extremely heavy. What is needed is a light weight, rigid, metal-reinforced, disassembled gate framing system for vinyl gates.
Likewise, metal-reinforced or metal-framed, gates in vinyl fencing systems are typically open at some point to weather. Some gates are merely painted, others have incomplete shielding by vinyl shrouds and the like. It would be an advance in the art, and a great improvement in the technology to form a metal framing system for vinyl gates in such a way as to use conventional vinyl parts as coverings for the gate framing members. It would also be a substantial improvement in the art to completely enclose the gate members against weather. It would also be an advance in the aesthetics of the art to develop a framing system using metal in rigidizing vinyl gates while completely enclosing metallic components from view and from weathering.
What is needed is a method and apparatus suitable for creating a comparatively rigid, durable frame for operating with vinyl fencing materials to be sheathed with vinyl for weather protection and aesthetics. What is also needed is a system that minimizes the weight of metal, maximizes the stiffness and strength of the frame and of the overall gate, takes a minimum volume to ship, and is comparatively simple to assemble at a destination site.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
In view of the foregoing, it is a primary object of the present invention to provide a system and method for a “knock-down” gate frame to be sheathed and assembled on site, during installation. In accordance with the invention, a gate framing apparatus and method are disclosed for supporting a plastic or other type of sheathed gate structure.
Consistent with the foregoing objects, and in accordance with the invention as embodied and broadly described herein, an apparatus and method are disclosed, in suitable detail to enable one of ordinary skill in the art to make and use the invention. In certain embodiments an apparatus and method in accordance with the present invention may include lateral b
Calton Robert H.
Hadfield, Sr. John L.
Browne Lynne H.
Cottingham John R.
Pate & Pierce & Baird
Vinyl Industries, Inc.
LandOfFree
Knocked-down, rigid, sheathed, gate frame does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Knocked-down, rigid, sheathed, gate frame, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Knocked-down, rigid, sheathed, gate frame will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2982704