Patent Grant
8347580
This invention relates to structural assemblies which may be formed from modular components, so as to provide varying sizes, configurations, and strength characteristics by combining only a limited number of parts. Such assemblies are very useful in the construction and maintenance of buildings, bridges, and other structures. In particular, the invention is directed to an improved structural member which is easily connected to like members and to other components using simple and economical fabrications, and for which the member's span strength and lateral rigidity may be increased by adding cooperating components and thereby forming a “composite” beam.
In the building trades, as well as in other industries, it is often necessary to configure a structural assembly in a non-uniform shape and to be able to quickly and easily move the assembly from one location to another. With specific reference to the construction industry, a scaffolding system or frame assembly is typically employed in close proximity to the building or structure being worked on, in order to provide artisans with a suitable area from which to perform their tasks. These tasks cover all aspects of a structure's construction and maintenance, including such diverse activities as applying materials to buildings under construction, washing the windows and exterior surfaces of completed buildings, and sandblasting and repainting the metal surfaces of bridge members.
In the past, scaffolding systems were constructed by bolting together vertical and horizontal members, and were essentially built from the ground up. These scaffolding systems were usually not movable, and therefore allowed access to only one portion of the building or structure at a time. To move on to the next portion of the building, it was usually necessary to disassemble the scaffolding system, relocate its base, and then reassemble the members involved. In addition to requiring a considerable amount of time and energy to dismantle and reassemble the scaffold each time it was moved, these prior art systems also presented significant safety risks to the workers using them. In addition, for most of these prior art scaffolding systems, the vertical height of the work platform could not be raised or lowered without dismantling a substantial portion of the scaffolding system.
Another problem that has become prevalent in modern construction and maintenance activities is the need for scaffolding systems which are readily adaptable in size and shape, and which can be easily configured to accommodate a variety of accessories. As the pace of building construction has increased, and the time available for completing each task has correspondingly decreased, such scaffolding systems have become key elements in the construction process. The variety and complexity of building shapes and structures has increased dramatically in recent years. Designing and fabricating customized scaffolding systems to fit particular building shapes and to accommodate particular tasks can be both time consuming and relatively expensive. Contemporary scaffolding systems must therefore be adaptable for use in many configurations and applications. The assembled platforms must also have sufficient span strength and torsional rigidity to safely hold both the workers using the scaffolding and their materials.
Recently, several scaffolding system improvements have been disclosed which alleviate a number of the problems noted above. U.S. Pat. No. 4,234,055, issued to G. L. Beeche on Nov. 18, 1980, describes a mobile suspension scaffold which requires assembly and dismantling only once for each construction site, at the beginning and the end of the job, respectively. The system described may be moved along the sides of a building and around building corners without being disassembled. A suspended scaffold system which may be used either independently or in conjunction with this mobile scaffold is the folding scaffold described in U.S. Pat. No. 4,253,548, issued to G. L. Beeche on Mar. 3, 1981. The system disclosed therein includes a plurality of work platforms which are foldably linked together. U.S. Pat. No. 4,967,875, issued to G. L. Beeche on Nov. 6, 1990, described a scaffolding system which employs modular components that may be combined to readily provide a variety of scaffold configurations and sizes. U.S. Pat. No. 5,203,428, issued to G. L. Beeche on Apr. 20, 1993, in turn discloses a scaffolding platform comprised of connected truss frames, which platform is particularly useful in conjunction with the scaffolding system disclosed by U.S. Pat. No. 4,967,875, and which may also be used independently thereof. The scaffold platform set forth in U.S. Pat. No. 5,203,428 is itself modular in nature, thereby further facilitating the assembly of scaffolding platforms which can conform to nearly any building size or shape. Finally, U.S. Pat. No. 5,214,899, issued to Beeche et al. on Jun. 1, 1993, describes a truss frame that is assembled from lightweight, modular components which are designed so as to provide the assembled frame with exceptional strength and rigidity.
For these and other commercially available scaffolding systems, the strength provided in the vertical and horizontal directions must be traded off against the amount of material used in the structural members, and, correspondingly, the cost and weight of those members. Another factor which must be considered is the availability and complexity required for components used to attach the scaffolding members to other structures.
In typical scaffolding applications, structural members are subject to both vertical load forces and horizontal deforming forces, produced, in part, by reaction to the load forces. For any given situation, either the vertical and horizontal strength provided by the structural member must be sufficient to withstand such forces, or appropriate additional bracing of the member must be incorporated into the scaffold design.
A cylindrically-shaped tube provides equal strength in the vertical and horizontal directions, so it does not need bracing to increase its horizontal strength. However, most scaffolding applications do not require equal amounts of horizontal and vertical strength, and a cylindrical design is therefore inefficient in that the member includes more metal material in certain locations than is necessary. Furthermore, the cylindrical shape of the member requires the use of special, non-standard accessories for such items as trolleys and building column mounts, which are relatively costly compared to available, off-the-shelf components.
Similarly, a square-shaped tube provides equal strength in both directions. Once again, however, since equal strength is usually not required in both the horizontal and vertical directions, such a member is also an inefficient use of metal material. To remedy that problem, a rectangularly-shaped tube may be formed. Doing so results in a non-symmetrical shape which reduces the modularity of the structural member. More importantly, a square-shaped or rectangularly-shaped tube presents its own difficulties with respect to attaching the members to like members and to other components. For example, in trolley/track applications, it is relatively difficult to attach the member to building columns without interfering with trolley travel.
Conventional I-beams provide significantly higher vertical strength than horizontal strength, and the top and bottom flanges incorporated therein provide better accessibility for attachments. However, because a conventional I-beam uses only a single web member between the flanges, the horizontal strength provided is significantly less than that provided by a square-shaped or rectangularly-shaped tube (both of which essentially have two web members).
What is needed, then, is a structural member which combines the desirable features of each of these prior art devices, one which makes an efficient use of the metal material while providing sufficient strength in both directions, and which provides ready access for connecting both like members and conventional accessories.
Accordingly, it is an object of the present invention to provide an improved structural member having increased horizontal strength compared to conventional I-beams, while utilizing an equivalent amount of material.
It is another object of the present invention to provide a structural member which is readily useable with conventional accessory components, such as trolleys and building infrastructure elements.
It is a further object of the present invention to provide a structural member for which the vertical and horizontal strength thereof may be increased by adding removable, cooperating modular components, so as to form a modular beam system wherein the same standard components are useable for multiple applications requiring varying member strengths.
It is also an object of this invention to provide a structural member which is readily and easily attachable to like members, both in an end-to-end relationship and in a perpendicular relationship.
It is an additional object of the present invention to provide a structural member and associated components which may be assembled in a modular fashion to form scaffolding systems having varying shapes, sizes, and strength characteristics.
The structural member of the present invention comprises a pair of top flanges which each extend along the length of the member in a separated and opposed co-planar fashion, and a pair of similarly separated and opposed co-planar bottom flanges which also each extend throughout the member's length. At least two web members connect the lowermost surfaces of the top flanges to the uppermost surfaces of the bottom flanges, and at least one leg member is disposed so as to connect the web members together in a spaced-apart relationship with respect to each other. In an especially useful embodiment, two leg members are used, the web members and the leg members each extend throughout the length of the structural member, and the web members and leg members are further disposed so as to form a rectangular central channel which extends along the length of the structural member, as well as two generally rectangularly-shaped slots which each extend in the same direction, with one of these slots located above the central channel and the other located below it.
The present invention further comprises cooperatively configured components which may be utilized to connect the inventive structural members together in end-to-end and perpendicular relationships, and also strengthening members which may be added to or removed from the structural members, as needed. The invention additionally includes components for attaching the structural members to other mechanisms and to conventional accessories, so as to provide a modular beam and scaffold system which is useful in many applications.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention itself, however, both as to its organization and its method of practice, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in which:
As is schematically illustrated by
Member 31 further comprises web member 38 which serves to connect the lowermost surface of top flange 30 with the uppermost surface of bottom flange 34, and to hold said flanges in a spaced-apart relationship. Web member 40 similarly connects and holds top flange 32 and bottom flange 36.
At least one leg member 42 is disposed between web members 38 and 40 so as to connect web members 38 and 40 together and to hold them in a spaced-apart relationship. In the embodiment illustrated by
For the embodiment illustrated by
As can be seen from
In the preferred embodiment illustrated by
As illustrated in
Schematically illustrated in
With end connector 58 inserted into channel 44 in the manner illustrated, and with fasteners inserted through corresponding openings 54 and 60 so as to “pin” the two adjoining ends of members 31 together, this end-to-end connection between members 31 serves to continue the condition of top flanges 30 and 32 being in compression and bottom flanges 34 and 36 being in tension, when member 31 is subjected to a vertical load.
In the alternative embodiment schematically illustrated by
Of course, for all of the arrangements shown in
It can be seen from the foregoing discussion that the structural member of the present, invention provides increased horizontal strength compared to conventional I-beams, while utilizing an equivalent amount of material. At the same time, the inventive structure incorporates elements which facilitate connection of the member to other like members, as well as to external structures and accessories. Furthermore, these same structural members may be utilized to form a “composite” beam system having increased strength, by assembling thereto removable, cooperating beam components. Hence, the present invention provides reusable modular components which may be readily combined to meet a variety of application requirements.
While the invention has been described in detail herein in accord with certain preferred embodiments thereof, many modifications and changes therein may be effected by those skilled in the art. Accordingly, it is intended by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.
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| Number | Date | Country | |
|---|---|---|---|
| 20040128942 A1 | Jul 2004 | US |
