Utility scaffolding having safety features

Information

  • Patent Grant
  • 6471003
  • Patent Number
    6,471,003
  • Date Filed
    Friday, January 19, 2001
    24 years ago
  • Date Issued
    Tuesday, October 29, 2002
    22 years ago
  • Inventors
  • Examiners
    • Chin-Shue; Alvin
    Agents
    • Hovey Williams LLP
Abstract
Scaffolding (10) having safety features for coupling scaffolding structural members so as to prevent equipment damage and worker injury from inadvertent disassembly, while permitting quick assembly and disassembly when desired. The scaffolding (10) incorporating the safety features broadly comprises legs (12); beams (14); a platform (16); coupling braces (18); platform pins (20); and platform clips (22). The first safety feature is a rounded, spring-biased, rotation-limited G-pin for adjustably coupling the beams (14) with the legs (12). The G-pin's rounded shape and a perpendicularly projecting stop (51) minimize risks of inadvertent removal. The second feature is a lockable pin (44) operable to independently couple structural members (12,14) in the event the G-pin is inadvertently removed. The third and fourth features are platform pins (20) and spring-biased platform clips (22) operable to prevent, respectively, undesirable horizontal and vertical movement of the platform (16).
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to scaffolding for providing an elevated work surface. More particularly, the invention relates to safety features for securing assembled scaffolding to prevent inadvertent disassembly and potentially resulting damage and injury.




2. Description of the Prior Art




Those ordinarily skilled in the art will appreciate that scaffolding is designed to be easily and quickly assembled where needed and disassembled for subsequent transport or storage. Unfortunately, in providing quickly connectable/disconnectable scaffolding assembly mechanisms, many existing scaffolding systems sacrifice safety and are prone to inadvertent and unsafe disassembly potentially resulting in damage or injury.




Such scaffolding is typically modular, with each module comprising four vertical legs, two horizontal beams, four coupling braces, and a work surface or platform, with the braces adjustably coupling the beams to the legs, and the work surface resting upon the beams.




Existing scaffolding systems typically use L-pins for coupling the braces with the legs. The legs and braces are each provided with a plurality of alignable first and second holes, respectively, through which the L-pins may be inserted. Platform height may be adjusted by removing the L-pins, repositioning the coupling braces to the desired height on the legs and replacing the L-pins in the corresponding aligned first and second holes. One disadvantage of the L-pin design is that it presents a projecting handle portion prone to catching on passing objects which can cause the L-pin to be inadvertently removed from the holes, thereby uncoupling the brace from the leg. This is particularly true where vibration in the scaffolding or other circumstances cause the L-pin to rotate so that its projecting handle portion extends outwardly in a manner especially suited to catch or snag upon passing objects.




Furthermore, the platforms are typically unsecured on the beams, relying only on contact with a beam lip to remain in place. Where platforms are warped or otherwise damaged, or are improperly placed upon the beams, they are prone to inadvertently slipping off the scaffolding.




Because existing scaffolding systems use assembly mechanisms that may result in inadvertent and unsafe disassembly of the scaffolding structure, a need exists for an improved system incorporating safety features to provide a more secure and reliable elevated work surface.




SUMMARY OF THE INVENTION




The present invention solves the above-described and other problems and provides a distinct advance in the art of safe scaffolding. More particularly, the present invention provides features which may be used in combination or independently to more safely and securely couple scaffolding members, including coupling the braces to the legs and the platform to the beams.




The first feature provides a round-handled, spring-biased, rotation-limited G-pin for adjustably coupling the legs to the braces. The G-pin is removably insertable into aligned first and second holes in, respectively, the leg and brace members, and includes a perpendicularly projecting stop, preferably a small roll pin, which prevents the G-pin from rotating outwardly and exposing itself to passing objects. The rounded shape of the G-pin's handle further minimizes potential snagging.




The second feature provides a lockable pin operable to support the coupling brace in the event the G-pin is inadvertently removed. The locking pin is insertable through a second pair of aligned first and second holes, parallel to the G-pin. The locking pin preferably extends completely through the brace and leg so as to provide a protruding portion adapted to receive a fastener.




The third and fourth features act to prevent inadvertent movement of the platform relative to the beams. The third feature provides platform pins welded or otherwise secured to the beams and rising upwardly therefrom to fit into pin holes drilled into the platform. Once the platform pins are received within the pin holes, the platform is prevented from shifting horizontally off of the beams. The fourth feature provides spring-biased C-clips operable to engage the beams and platform so as to prevent relative vertical movement therebetween and ensure that the platform will not inadvertently lift off the platform pins due, for example, to warping or vibration.




These novel features provide a safer and more reliable scaffolding structure than currently exists in the art, and are described in more detail in the section entitled DESCRIPTION OF A PREFERRED EMBODIMENT, below.











BRIEF DESCRIPTION OF THE DRAWING FIGURES




A preferred embodiment of the present invention is described in detail below with reference to the attached drawing figures, wherein:





FIG. 1

is a perspective view of scaffolding incorporating preferred embodiments of the four safety features of the present invention;





FIG. 2

is a fragmentary isometric view of a portion of the scaffolding of

FIG. 1

showing in detail preferred embodiments of a first two of the safety features of the present invention; and





FIG. 3

is a sectional view of a portion of the scaffolding of

FIG. 1

showing in detail preferred embodiments of a second two of the safety features of the present invention.











DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT




Referring to

FIG. 1

, scaffolding


10


is shown operable to provide an elevated work surface for one or more workers. It should be noted that the present invention is for safety features for securely coupling scaffolding structural members so as to permit quick and easy assembly and disassembly thereof while preventing potential equipment damage and worker injury resulting from inadvertent disassembly. These safety features are independent of any particular scaffolding design, type, or brand, and are not limited to the particular scaffolding


10


shown for illustrative purposes only.




The scaffolding


10


broadly comprises four legs


12


; two beams


14


; a platform


16


; four coupling braces


18


; four platform pins


20


; and two platform clips


22


. The legs


12


are vertical support members for elevating the scaffolding structure. The legs


12


may vary in appearance and design but are preferably elongated hollow square or round tubes. A plurality of cross-bars


26


are welded between pairs of legs


12


to produce an end-frame unit of two fixedly-spaced legs and a ladder-like structure therebetween for allowing workers easier access to the elevated platform


16


.




Each leg


12


includes a plurality of first holes


28


drilled therethrough at spaced intervals corresponding to the various possible heights to which the work platform


16


may be elevated. The number of such holes


28


is a matter of design choice. In a less preferred embodiment, only one or two holes are provided, in which case the work surface height is not adjustable.




The beams


14


are horizontal support members providing horizontal support for the scaffolding structure and, in particular, the platform


16


. The beams


14


may vary in appearance and design but, when assembled, are supported by the coupling braces


18


to extend between the legs


12


.




As is best shown in

FIG. 3

, the preferred beam


14


comprises a back


56


; a top and bottom


57


,


58


; and a lip


60


. The back


56


is an elongated rectangular piece of material, preferably metal, having first and second long edges and first and second short edges. The top and bottom


57


,


58


extend perpendicularly outward from, respectively, the first and second long edges. The lip


60


extends perpendicularly from the top


57


and parallel to the back


56


. The work surface


16


rests upon the top


57


of the beam


14


, and abuts the lip


60


which helps to prevent undesired movement of the properly positioned platform


16


.




Referring to

FIGS. 1 and 2

, the platform


16


provides a work surface operable, when supported by the beams


14


and elevated by the legs


12


, to support one or more workers and their equipment. The platform


16


may vary in appearance and design but is preferably ⅝ inch plywood or other material of similar strength. The platform


16


preferably includes handholds


30


cut thereinto to allow for easier handling, and pin holes


32


drilled therethrough to accommodate the platform pins


20


as described below.




Referring to

FIG. 2

, the coupling braces


18


are shown operable to adjustably and securely couple the legs


12


with the beams


14


while permitting quick and easy assembly and disassembly thereof. Each coupling brace


18


comprises a sleeve


40


; a G-pin


42


; a locking pin


44


; and a bracket


46


.




A first portion of the sleeve


40


allows the brace


18


to be adjustably coupled with the leg


14


. The sleeve


40


slidably fits over the leg


14


and presents at least two second holes


48


alignable with two of the first holes


28


in the leg


14


. A second portion of the sleeve


40


is preferably welded or otherwise secured to the beam


14


.




The G-pin


42


is operable to be retractably inserted through one of the second holes


48


and into or through one of the first holes


28


, thereby securing the sleeve


40


to the leg


12


. The G-pin


42


is preferably retained within and guided by a pin guide


50


projecting from the beam


14


and having at least one guide hole for receiving and slidably passing therethrough the G-pin


42


. The G-pin


42


is preferably spring-biased by a spring (not shown) which must be actuated in order to position the sleeve


40


for insertion and removal of the G-pin


42


into and from the first holes


28


.




The G-pin


42


includes a projecting handle portion


43


for gripping when inserting or removing the G-pin


42


. Although the handle portion


43


is preferably rounded, being G- or O-shaped, it may be more generally said that the pin


42


preferably includes a handle portion


43


which first projects away from the pin's axis and then curves or bends back toward the axis in such a manner so as to be less likely to catch or snag upon passing objects.




To further minimize potential snagging, the G-pin


42


includes a perpendicularly projecting roll pin


51


or other projection being of a length and positioned so that, when the G-pin


42


is rotated outwardly, the roll pin


51


contacts a portion of the pin guide


50


, beam


14


, or leg


12


and prevents further rotation. Thus, the roll pin


51


restricts the G-pin


42


from rotating outwardly into a position whereby it would protrude beyond the leg and beam


12


,


14


and be more likely to snag passing objects.




As will be appreciated by those with skill in the art, in some applications it may be desirable to eliminate the G-shaped pin


42


of the present invention, retain the L-shaped or other pin conventionally used, and minimize snagging risks by severely limiting pin rotation using the roll pin


51


or a variation thereof. This is a generally less desirable embodiment because pin movement will be so restricted as to hamper efficient assembly and disassembly of the scaffolding. Nevertheless, it should be noted that the roll pin's anti-rotation function does not require a particular pin or pin shape.




The locking pin


44


is operable to independently couple the coupling brace


18


with the leg


12


in the event that the G-pin


42


is inadvertently withdrawn. The locking pin


44


removably inserts into aligned first and second holes


28


,


48


spaced apart from and parallel to the G-pin


42


. Unlike the G-pin


42


, the locking pin


44


is neither spring-biased nor rotationally limited, nor is it retained by a pin guide. Instead, the locking pin


44


preferably includes a first end


49


presenting a stop, and a second end


47


operable to receive a fastener


45


. The nature of the fastener


45


is a matter of design choice, but may be a hexnut, wingnut, cotter pin, C-clip, or other suitable fastener. In a preferred embodiment, the locking pin


44


is of such a length that, when inserted through the first and second holes


28


,


28


, the second end


47


protrudes beyond the leg


12


and sleeve


40


so that a wire yolk


45


may be attached to the first and second ends


43


,


47


of the inserted locking pin


44


thereby preventing the pin's inadvertent removal.




The bracket


46


, is supportively secured at one end to the sleeve


40


and at an other end to the beam


14


, thereby providing additional structural support for the platform-supporting member


14


.




Referring to

FIG. 3

, there are preferably four platform pins


20


per platform


16


, the pins being welded or otherwise secured in an upright position to the beams


14


. The platform pins


20


are received within the platform holes


32


when the platform


16


is properly placed upon the beams


14


. The engaged relationship of the platform pins


20


and holes


32


restricts horizontal movement of the platform


16


, thereby preventing it from inadvertently slipping off the beam


14


.




The platform clips


22


may be applied once the platform


16


is properly placed upon the beams


14


and the platform pins


20


are received within the pin holes


32


. A mounting pin


70


projects perpendicularly from the back


56


of the beam


14


, and a lower leg portion of the platform clip


22


presents a hole through which the mounting pin


70


may be inserted. A spring


71


surrounding the mounting pin


70


biases the clip


22


against the back


56


of the beam


14


. A top portion of the clip


22


is operable to slip over the lip


60


of the beam


14


to retractably engage the platform


16


and restrict vertical movement thereof. Thus, the platform clips


22


prevent the platform


16


from lifting off the platform pins


20


, making them particularly desirable where work surfaces may warp due to moisture or bend under a load. When either of these situations occur, without the platform clips


22


the surface


16


might lift off of the platform pins


20


and over the lip


60


and slip off of the beams


14


. Thus, the platform pins


20


and clips


22


operate together to prevent platform


16


movement.




In operation, to assemble the scaffolding


10


, each G-pin


50


is retracted from its spring-biased position, the legs


12


are placed within the sleeves


40


of the coupling braces


18


, and the first and second holes


28


,


28


aligned according to the desired platform height


16


. The G-pins


42


may then be released so that they pass through the second holes


48


and into the first holes, thereby securely coupling the sleeves


40


with the legs


12


. The locking pins


44


may thereafter be inserted into first and second holes parallel to the G-pins, and secured with the fasteners


45


.




The platform


16


is then positioned so that the platform pins


20


of the beams


14


are received within the pin holes


32


of the platform


16


. The platform clips


22


are pulled away from the back


56


of the beam


14


until the upper portion of the clip


22


can be rotated over the lip


60


and platform


16


. The platform clip


22


is then released to return to its spring-biased position, thereby securely engaging the platform


16


and holding it firmly upon the beam


14


.




Disassembly of the scaffolding


10


is accomplished by performing the preceeding described steps in reverse order.




Although the invention has been described with reference to the preferred embodiment illustrated in the attached drawing figures, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims. In particular, the present invention is for safety features for securely and safely coupling scaffolding structural members, and is independent of any particular scaffolding design, type, or brand.



Claims
  • 1. Scaffolding for providing an elevated work surface, the scaffolding comprising:a platform defining the work surface and having a pin hole; a support member for supporting the platform, said support member including a first platform pin projecting transversely from the support member; a second platform pin projecting uprightly from the support member and received within the pin hole and thereby restrict horizontal movement of the platform relative to the support member; and a platform clip operable to,simultaneously engage both the platform and the support member and to thereby restrict vertical movement of the platform relative to the support member, said platform clip being shiftably retained on the first platform pin for movement into and out of an engaged position wherein vertical movement of the platform relative to the support member is restricted.
  • 2. The scaffolding as set forth in claim 1, the platform clip being coupled with the support member so as to be spring-biased when in the engaged position.
  • 3. The scaffolding set as set forth in claim 1,said vertical support member including a plurality of first holes; a coupling mechanism slidably received on the vertical support member and fixed relative to the horizontal support member to vertically and adjustably couple the vertical support member with the horizontal support member, the coupling mechanism having a second hole alignable with anyone of the first holes; and a coupling pin insertable into an aligned pair of first and second holes.
  • 4. The scaffolding set as set forth in claim 3, each of said plurality of first holes being vertically spaced from one another, each of said first holes being associated with the horizontal support member being in a corresponding vertical adjustment relative to the vertical support member so that when the coupling pin is inserted into the aligned pair of holes the horizontal support member is retained in the corresponding vertical adjustment.
  • 5. The scaffolding set as set forth in claim 1,said platform clip being shiftable along and rotatable about the first platform pin.
  • 6. The scaffolding set as set forth in claim 1,said platform being vertically shiftable relative to the second platform pin when the pin hole is received on the second platform pin and the platform clip is out of the engaged position.
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Number Name Date Kind
3968606 Facemire Jul 1976 A
4048059 Evans Sep 1977 A
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4263984 Masuda Apr 1981 A
4484663 Wyse Nov 1984 A
4493394 Karlsen Jan 1985 A
4630956 Gilbreath Dec 1986 A
4825976 Wyse May 1989 A
5069309 Swiderski Dec 1991 A
5137414 Sloan et al. Aug 1992 A
5152371 Wyse Oct 1992 A
5931260 Beauchamp Aug 1999 A
6223857 Wyse May 2001 B1