Fire escape – ladder – or scaffold – Unitary foldable – rigid scaffold or ladder – Trestle
Reexamination Certificate
2003-03-25
2004-11-16
Thompson, II, Hugh B. (Department: 3634)
Fire escape, ladder, or scaffold
Unitary foldable, rigid scaffold or ladder
Trestle
C182S153000
Reexamination Certificate
active
06817445
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to sawhorses, and more particularly, to a single sawhorse having two separate support members that allow it to function as two sawhorses.
2. Description of the Related Art
Sawhorses are well known in the art and an example of one is provided by FIG. 1C of U.S. Pat. App. Pub. No. US2002/0011381. One of the most common uses of sawhorses is to support building materials during a construction project. Typically, the building materials are placed on the support members of two-sawhorses which are spaced a few feet apart with the two support members positioned in parallel. For example, when painting a strip of crown molding, a carpenter would place one end of the crown molding on the support member of one sawhorse and the other end of the crown molding on the support member of a second sawhorse. This would provide a raised support for the crown molding while allowing the carpenter to move freely around the crown molding while painting it. Sawhorses can be used in a similar manner to support other materials such as sheets of plywood or sheetrock and equipment such as a power miter saw.
The use of traditional sawhorses has at least two well-known drawbacks. First, traditional sawhorses are bulky and require significant amounts of space to both store and transport. And second, two traditional sawhorses are required to properly support a piece of building material.
Collapsible or foldable sawhorses such as those depicted in U.S. Pat. Nos. 4,819,762 and 5,927,436 to Osborne and Schutz, respectively, and in U.S. Pat. App. Pub. No. US2002/0011381 to Wilkerson have been introduced to reduce the space requirements of storing and transporting sawhorses. However, these collapsible or foldable sawhorses are generally more expensive than traditional sawhorses and thereby add to the expense of using sawhorses. Additionally, they require set-up time to unfold and are configured such that folding or unfolding often results in pinched fingers. Furthermore, they are not adjustable in height or width. Structurally, these sawhorses do not resemble the present invention.
Although, the prior art does not disclose a single sawhorse having two support members that serves the function of two sawhorses, it does disclose some workstations and other items that bear faint structural resemblances to the present invention. For example, U.S. Pat. No. 3,157,136 to Moody, U.S. Pat. No. 6,314,893 to Lee, and United Kingdom Pat. No. GB2,137,490, disclose respectively a folding support stand, a cutting machine table, and a baby care table. These devices are similar to the present invention in that each includes two sets of legs that open and close in a scissor-like motion. However, unlike the present invention, none of these devices is adjustable in height or width, nor includes cross-linked chains for added strength and stability.
Similarly, although the devices disclosed in U.S. Pat. No. 4,974,525 to Sheffield and U.S. Pat. No. 5,657,703 to Johnson include two sets of legs that open and close in a scissors-like motion and also include cross-linked chains, both of the devices differ structurally from the present invention in at least two respects. First neither of the devices is height adjustable and, second, neither of the devices' support member or members can be easily replaced with an inexpensive material such as a segment of two-by-four wood. Additionally, the Johnson device is complex in its configuration and, hence, is more expensive to manufacture.
Wherefore, none of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed and, thus, an adjustable sawhorse with two support members solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
The present invention is an adjustable sawhorse that functions as two sawhorses by providing two support members positioned several feet apart. The device is collapsible and can be adjusted to different heights and widths.
The device is comprised of two rectangular framed leg assemblies that are pivotally attached and operate with a scissors-like motion. Each leg assembly is comprised of a first and second “U” shaped tubular member with the first “U” shaped tubular member having a smaller diameter than that of the second, and with the sides of the first “U” shaped tubular member being slidably mounted inside the sides of the second. The second “U” shaped tubular member of each leg assembly includes two locking knobs to lock the first and second “U” shaped tubular members into place with respect to each other. The device includes two chains interlinking the two rectangular framed leg assemblies and a support member pivotally attached to the uppermost cross bar of each leg assembly. The device also includes a separate fastening strap to secure the device in its collapsed position.
The height and width of the device can be adjusted by either adjusting the length of the interlinking chains or by adjusting the size of each of the rectangular framed leg assemblies. The size of the leg assemblies are adjusted by sliding the first “U” shaped tubular member further into or out of the second “U” shaped tubular member.
The fastening strap is made of hook and loop fastening material. The support members are constructed of segments of two-by-four wood and can be easily replaced if damaged. All other components are constructed of galvanized steel.
Accordingly, it is a principal object of the invention to eliminate the need for two separate sawhorses when supporting building materials or equipment and to thereby reduce the costs associated with sawhorses.
It is another object of the invention to provide a sawhorse that is easily stored and transported.
It is a further object of the invention to provide a sawhorse with two support members wherein the height and spacing of the support members can be adjusted.
Still another object of the invention is to provide a sawhorse that incorporates two chains and four cross bars for stability.
Additionally, another object of the invention is to provide a sawhorse that incorporates two support members that, when damaged, can be easily replaced with commercially available materials.
Further, another object of the invention is to provide an adjustable and collapsible sawhorse that can be readily and easily opened, collapsed and adjusted.
Furthermore, another object of the invention is to provide a sawhorse with a minimal number of components that is simple and inexpensive to manufacture.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
REFERENCES:
patent: 295269 (1884-03-01), Miller
patent: 296209 (1884-04-01), Nelson
patent: 3157136 (1964-11-01), Moody
patent: 4819762 (1989-04-01), Osborne, Sr.
patent: 4974525 (1990-12-01), Sheffield
patent: 5657703 (1997-08-01), Johnson
patent: 5927436 (1999-07-01), Schutz
patent: 6314893 (2001-11-01), Lee
patent: 6536359 (2003-03-01), Liu
patent: 2002/0011381 (2002-01-01), Wilkerson
patent: 2 137 490 (1984-10-01), None
Litman Richard C
Thompson II Hugh B.
LandOfFree
Adjustable sawhorse with two support members does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adjustable sawhorse with two support members, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adjustable sawhorse with two support members will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3338437