Information
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Patent Grant
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6471003
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Patent Number
6,471,003
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Date Filed
Friday, January 19, 200124 years ago
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Date Issued
Tuesday, October 29, 200222 years ago
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Inventors
-
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Examiners
Agents
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CPC
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US Classifications
Field of Search
US
- 182 118
- 182 119
- 182 222
- 182 115
- 182 141
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International Classifications
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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.
US Referenced Citations (13)