Note: Descriptions are shown in the official language in which they were submitted.
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SCAFFOLD SAFETY APPARATUS
BACKGROUND OF THE INVENTION
The U.S. Department of Labor sets out certain criteria to protect construction
workers from falling off high area platforms, including scaffolds. For
instance, the
criteria require, in part, that the workers be tied-off while working on such
platforms to
prevent accidental falls. Various devices have been used to tie-off or secure
workers,
but many of them are not suitable for erecting or building a scaffold and
often have
several drawbacks.
For example, some safety devices restrict workers to a work area of one or two
square meters which impede or slow down their ability to work efficiently and
get the
job completed quickly. Other safety devices prevent workers from moving
between
sections of scaffold because a lanyard, the cord that connects the harness to
the safety
device, often gets caught on the scaffold structure or the safety device
itself. Hence,
workers create a dangerous situation because, many times, they have to
disconnect the
lanyard from the safety device, move to the next section of scaffold, and
reconnect to a
safety device on this scaffold section. Workers can accidentally fall when
moving
between sections with such a device, or sometimes they forget to reconnect all
together.
Hence, a need exists for a scaffold safety device that allows workers to build
or
erect a scaffold. A further need exists to allow workers to be tied-off, but
provide a
larger work area. Yet, another need exists for a scaffold safety device that
does not
require a worker to disconnect and/or reconnect to a safety device when moving
between more than one scaffold section.
SUMMARY OF THE INVENTION
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The present invention relates to a scaffold safety apparatus that allows one
or
more construction workers to safely tie-off when on a scaffold, while allowing
the
worker to move across one or more scaffold sections without having to
disengage the
safety line. In one embodiment, the safety apparatus (e.g., safety device or
safety
mount) includes two offset elongated members disposed in essentially parallel
directions. At least one of these two elongated members has a device that
engages a
safety line (e.g., a cable clamp, a cable grab, a hook, or any combination
thereof). The
safety apparatus also has a connector that connects one elongated member to
the other
elongated member, and an attachment for securing at least one elongated member
to the
scaffold (e.g., a clamp, a clasp, a nut & bolt arrangement, a fastener, a
grip, a vise,
quick-release snap clamp, or any combination thereof). The connector connects,
for
instance, a top section of one elongated member to a bottom section of the
other
elongated member. The elongated members are offset by a distance in an amount
to
allow, when installed, a person to move across one or more scaffold sections,
and for
example, in an amount between about 1 inch (about 2.54 cm) and about 12 inches
(about
30.5 cm). Another embodiment further includes having a safety line engaged to
the
device.
The present invention also is directed to a scaffold safety mount that
includes a
first elongated member having an attachment for securing the first elongated
member to
a scaffold, a second elongated member, disposed in a direction essentially
parallel to that
of the first elongated member. The mount also has a device for engaging a
safety line,
and a cross bar connecting the top section of the first elongated member to
the bottom
section of the second elongated member. The first elongated member has a
length
sufficient to have an attachment for securing the member to the scaffold,
e.g., a length
between about 2 feet (about 61 cm) and about 6 feet (about 183 cm). The second
elongated member has a length sufficient to connect to the device for engaging
the
safety line, e.g., a length between about 2 feet (about 61 cm) and about 6
feet (about 183
cm). The cross bar has a length sufficient to connect the elongated members so
that a
person using the device, when installed, extends past the innermost portion of
the
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scaffold, and allows one to move across more than one scaffold section without
having
to disengage, e.g., a length between about 1 inch (about 2.54 cm) and about 12
inches
(about 30.5 cm).
The scaffold safety apparatus can be constructed from in a single piece, or
from
more than one piece. The apparatus of the present invention can also be made
of a
single type of material, different types of materials, blends of materials, or
any
combination thereof. In one embodiment, the elongated members and/or the cross
bar
can be made from a metal (e.g., steel, titanium, or any combination thereof),
alloy,
plastic, or any combination thereof.
The present invention additionally relates to a scaffold safety apparatus that
includes two offset elongated members disposed in essentially parallel
directions, at
least one of the two elongated members having a hook for engaging a safety
line; a
connector that connects the bottom section of the first elongated member to
the top
section of the second elongated member; and a clamp for securing at least one
elongated
member to a scaffold.
The present invention also pertains to a safety scaffold system. The system
includes more than one scaffold safety apparatus, as described herein, and a
safety line
engaged to the device (e.g., a hook). When the system is installed, the system
allows a
person to move across one or more scaffold sections without having to
disengage the
safety line. The safety line is positioned so that the line is secured to the
device for
engaging the safety line, double looped and secured (e.g., reattached). The
safety line is
attached to withstand a weight of between about 5000 lbs. ( 2267.96 kilograms)
and
about 20,000 lbs. (9,071.85 kilograms). The present invention further includes
a harness
system (e.g., a harness that is secured to the person, and a lanyard that
connects the
harness to the safety line) or body-belt system (e.g., a body belt that is
secured to the
person and lanyard that connects the body-belt to the safety line) for
engaging a person
to the safety line.
Another aspect of the present invention is a scaffold safety system that has a
scaffold, a device for engaging a safety line, an attachment for securing the
device to the
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scaffold; and a safety line engaged to the device. The safety line is threaded
through the
device for engaging the safety line, double looped, and reattached. The
attachment for
securing the device to the scaffold is positioned such that the safety line
clears the
innermost portion of the scaffold structure.
The methods of the present invention include methods for erecting or building
a
scaffold. The steps embody erecting or installing the first scaffold level and
attaching
the safety system, as described herein. The methods further include securing a
person to
the safety system, and installing a second scaffold level while secured to the
safety
system. These steps can be repeated to build or erect additional scaffold
levels.
The present invention also relates to methods for a person to safely use a
scaffold. The steps of the methods include, in one embodiment, engaging a
person to a
safety line of a safety scaffold system; engaging the safety line to the
safety scaffold
system, as described herein, and moving across one or more scaffold sections
without
disengaging the safety line. The method further includes a person engaging to
the safety
line with a lanyard hook, a lanyard and harness.
Yet another embodiment of the present invention relates to a safety scaffold
structure that includes a scaffold (e.g., a frame and brace type scaffold, a
cup lock type
scaffold, a quick erect system scaffold, tube and clamp type system scaffold,
a systems
scaffold, or any combination thereof) having one or more scaffold sections;
and the
scaffold safety apparatus described herein.
The present invention also embodies a scaffold safety kit that has one or more
scaffold safety apparatuses described herein and a safety line. The kit can
additionally
include a harness system or body-belt system.
One aspect of the present invention includes scaffold safety systems that
contain
a scaffold, more than one device for engaging a safety line; more than one
attachment
for securing the device to the scaffold; and a safety line engaged to the
devices, wherein
the safety line is double-looped. Another aspect of the invention pertains to
a scaffold
safety system that includes a scaffold railing; and a support secured to the
scaffold
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railing. The support has a device for engaging a safety line past the inside
portion of the
scaffold railing and includes at least one elongated member.
Another embodiment of the present invention is a scaffold safety apparatus for
use on a scaffold having a scaffold railing, wherein the apparatus has at
least one
elongated member having a device for engaging a safety line; and one or more
attachments for securing at least one elongated member to the scaffold;
wherein, when
installed on the scaffold, one of the following occurs: the apparatus is
positioned to
extend past the inner portion of the scaffold railing; the apparatus is offset
in an amount
greater than a distance between an inner and outer scaffold railing; the
apparatus is
offset by a distance of between about 1 inch (about 2.54 cm) and about 12
inches (about
30.5 cm); the apparatus is angled by an amount between about 145 degrees and
about
180 degrees from the point of attachment to the scaffold.
The present invention has several advantages. The scaffold safety apparatus of
the present invention allows for one to be secured while erecting or building
a scaffold.
It also provides a larger, more accessible work space for the worker, while
being tied off
or secured. Additionally, the present invention allows one to move across more
than
one section of scaffold without having to disconnect and reconnect to the
safety line,
unlike some devices currently on the market. Hence, the present invention
increases
safety without minimizing productivity.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will
be
apparent from the following more particular description of preferred
embodiments of the
invention, as illustrated in the accompanying drawings in which like reference
characters refer to the same parts throughout the different views. The
drawings are not
necessarily to scale, emphasis instead being placed upon illustrating the
principles of the
invention.
Fig. 1A is a diagram showing a side view of one embodiment of the scaffold
safety apparatus.
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Fig. l B is a diagram showing a perspective view of one embodiment of the
scaffold safety apparatus.
Fig. 1 C is a diagram showing a detailed view of the clamp attachment shown
Fig. 1B.
Fig. 1 C-1 is a diagram showing another detailed view of the clamp attachment
shown in Fig. 1B.
Fig. iD is a diagram showing a side view of one embodiment of the scaffold
safety apparatus.
Fig. lE is a diagram showing a side view of another embodiment of the scaffold
safety apparatus.
Fig. I F is a diagram showing a side view of another embodiment of the
scaffold
safety apparatus.
Fig. 1 G is a diagram showing a side view of another embodiment of the
scaffold
safety apparatus.
Fig. 1 H is a diagram showing a side view of another embodiment of the
scaffold
safety apparatus.
Fig. 2A is a diagram showing a perspective view of one embodiment of the
scaffold safety system.
Fig. 2B is a diagram showing a detailed view of the installed safety apparatus
of
Fig. 2A.
Fig. 3A is a diagram showing a front view of an embodiment of the scaffold
safety system as installed on a Frame & Brace Type scaffold.
Fig. 3B is a diagram showing a side view of one embodiment of the scaffold
safety system as installed on a Frame & Brace Type scaffold.
Fig. 3C is a diagram showing a bird's eye view of one embodiment of the
scaffold safety system as installed on a Frame & Brace Type scaffold.
Fig. 4A is a diagram showing a front view of an embodiment of the scaffold
safety system as installed on a Cup-Lock Type scaffold.
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Fig. 4B is a diagram showing a side view of one embodiment of the scaffold
safety system as installed on a Cup-Lock Type scaffold.
Fig. 4C is a diagram showing a bird's eye view of one embodiment of the
scaffold safety system as installed on a Cup-Lock Type scaffold.
DETAILED DESCRIPTION OF THE INVENTION
A description of preferred embodiments of the invention follows.
The present invention relates to a scaffold safety apparatus (e.g., mount)
that is
constructed to allow a person (e.g., a construction worker) to be securely
tied off to a
safety line, but at the same time, allows the person to move across multiple
sections of
scaffold. The ability to move across multiple sections of scaffold more easily
allows
workers to build or erect a scaffold, or to work on a scaffold level more
productively. In
particular, the present invention includes an apparatus that has two elongated
members
that are positioned in parallel directions. These elongated members are
offset, as further
described herein, by a distance to clear the inside portion (e.g., innermost
portion) of the
scaffold structure, when installed on a scaffold. Another aspect of the
invention
involves the scaffold safety system that includes the safety apparatus and a
safety line.
The safety line is attached to the safety apparatus and doubled looped along
the length of
the scaffold sections, as further described herein. The design of the
apparatus coupled
with the double looped safety line provides for a system that allows a person
to walk
along multiple scaffold sections without having to disconnect and/or reconnect
to the
safety line.
Referring to Figs. I A-C, scaffold safety apparatus 20 has elongated member
l0A
and elongated member l OB that are positioned in a parallel fashion, and
secured with
diagonal supports 21A and B. Generally, the members can be disposed in
essentially
parallel directions, meaning that the members may be parallel or, if not
exactly parallel
both are disposed in primarily the same direction (e.g., vertically). Fig. lA
is a side
view of the apparatus, Fig. 1 B is a perspective view of the same embodiment
of the
apparatus, and Figs. 1C and 1C-1 show a detailed view of the clamp used to
secure the
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apparatus to the scaffold railing. As shown in the diagram, elongated member
l0A and
member l OB are offset by distance D of a length sufficient to clear the
inside portion of
the scaffold railing. Elongated members have a length sufficient to allow for
the
member to be secured to the scaffold with the attachment, e.g., a length
between about 2
feet (about 61 cm) and about 6 feet (about 183 cm).
Although, in this embodiment, the elongated members are parallel, they can
assume other positions so long as the device for engaging a safety line
extends beyond
the innermost portion of the scaffold railing on which it is installed. See
Figs 1D-H
below for examples. This positioning of the member allows for a person to walk
freely
along one or more scaffold sections when the person is secured to a safety
line (e.g., a
doubled looped safety line) that is engaged to the safety apparatus.
Members 10A and lOB are connected by cross bar 14, as seen in Figs. lA-B.
Cross bar 14 connects the bottom portion of one elongated member, e.g., member
10A,
with the top portion of another elongated member, e.g., member l OB. In
addition to
cross bar 14, other connecting means can be employed to attach members I OA
and l OB
so long as they are positioned as described herein. Examples include, e.g.,
screws,
diagonally positioned bars,"X" type attachments, cross type attachments, and
others.
Any connectors or attachments can be used, including those that are developed
in the
future, so long as the device for engaging the safety line is secured and
positioned as
described herein. Such connectors are known in the art, and are commercially
available
from, e.g., Harding Co. (Exeter, New Hampshire), or Colony Co. (New Haven,
Connecticut). The connection can be permanent, e.g., welded, or can be
reversibly
attached, e.g., with clamps or screws. Elongated members are offset by a
distance
sufficient to place elongated member l0A in a position to clear the inside
portion of the
scaffold railing on which the apparatus is installed. The offset amount also
depends on
the design of the scaffold and the position of the inside railing. For
example, for several
of the existing scaffolds, offsetting the elongated members by a distance in
an amount
between about 1 inch (about 2.54 cm) and about 12 inches (about 30.5 cm)
generally
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extends the device for engaging the safety line past the inside portion of the
scaffold
railing.
The apparatus, including the elongated members and/or the connector, can be
made from several types of materials including metal, an alloy, plastic, any
other
suitable material, or combinations thereof. Any type of material can be used
so long as
the material has the strength to withstand the force of an accidental fall of
a person using
the device. Examples of such materials include steel, titanium, or a
combination thereof.
Figs. lA and 1B also show hook 16. Hook 16 is mounted to elongated member
10A. When installed on a scaffold, hook 16 extends past the inside railing of
the
scaffold on which the apparatus is installed. Hook 16 is used to engage a
safety line.
Examples of other devices that can be employed for engaging a safety line
include cable
clamps, cable grabs, hooks, catches or combinations thereof. Examples of
various types
of hooks can be used and include a form hook, a locking snap hook (e.g., U.S.
Patent
No. 4,527,728 and 4,434,536), a double lock hook, a ladder hook, and a twist &
lock
hook. Any device known in the art or developed in the future can be used so
long as the
device can securely engage a safety line. Such devices are commercially
available and
can be obtained, e.g., from Spider , a division of SafeWorks, LLC (Tukwila,
Washington), or Rose Manufacturing company (Englewood, Colorado).
Clamps 14 A and 14B, referring to Figs lA-C, are attachments for securing
member l OB to the scaffold. The attachment of the safety device can be
permanently
welded, or reversibly attached to the scaffold. One or more attachments for
securing the
safety apparatus to the scaffold can be used and can be attached to any
portion of the
apparatus. The attachments can be connected to a vertical member of the
scaffold, a
horizontal member of the scaffold or to a locking mechanism of the scaffold
(e.g., a cup
lock type scaffold). Attachments include, for example, clamps, clasps, nut &
bolt
arrangements, fasteners, grips, vises, quick-release snap clamp, and any
combination
thereof. Examples of clamps that can be used include beam clamps, right angle
clamps,
T-bolt clamps, eye-bolt clamps and swivel clamps. Such attachments are
commercially
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available and can be obtained from, Safway Services, Inc. (Waukesha,
Wisconsin);
Harding co (Exeter, New Hampshire) and Edge International (Laguna Niguel,
California). Any attachment, including those that are known and those
developed in the
future, can be used so long as the safety device is securely attached to the
scaffold.
Apparatus 20 can be installed on many types of scaffold including, for
example,
frame and brace type scaffolds, cup lock type scaffolds, quick erect system
scaffolds,
tube and clamp system scaffolds, systems scaffolds, or any combination
thereof, as
further described herein. Embodiments of the present invention, such as
apparatus 20,
universally fits and can be used all of the five types of scaffold listed
above.
In one embodiment, the apparatus can be interwoven into the structure of the
scaffold. Generally, scaffolds have levels that are connected or interlocked.
They can
be connected in various ways, such as using male and female ends (e.g., frame
and brace
type scaffold), or locking mechanisms (e.g., a cup lock type scaffold). The
apparatus
can have an attachment that takes advantage of the method for interlocking
levels of the
scaffold. For example, the apparatus can have a male or female end that is
inserted into
or received by a vertical or horizontal post of a scaffold, or have an
extension that locks
into the cup-locking mechanism.
Additional embodiments of the safety apparatus are shown in Figs. 1 D-1 H.
These embodiments of the safety apparatus illustrate that the device can be
designed in
various ways so long as the device for engaging the safety line, if installed
on a scaffold,
would extend past the inner portion of the scaffold railing. This positioning
past the
inner portion of the scaffold railing can be further described by the angle of
the device in
relation to its base or point of attachment to the scaffold, or even its
relationship to the
scaffold railing. The positioning of the device for engaging the safety line
can also be
described by a distance by which the device extends from its base or scaffold
railing.
For example, an embodiment of the invention includes a support having a base
for
attachment to the scaffold and device for engaging a safety line. The support
extends so
as to put the device in a position past the inner portion of the scaffold
railing. In the
embodiment described in Figs. lA-C, this position accomplished by cross bar 12
that
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offsets elongated member I OA by an amount between about 1 inch (about 2.54
cm) and
about 12 inches (about 30.5 cm) (e.g., 11 inches). Using the same embodiment,
the
position of the device for engaging the safety line is at an angle between
about 145
degrees and about 180 degrees (e.g., 157 degrees) with respect to elongated
member
l OB's point of attachment (e.g., the base or the support). Fig. 1 D shows an
embodiment
of the apparatus having only one elongated member, elongated member 10A.
Clamps
14A and B are connected to elongated member l0A with extension bars 15A and B.
Extension bars 15A and B offset hook 16 so that hook 16 extends past the
scaffold
railing when installed. Similarly, Fig lE shows an embodiment of the present
invention
in which hook 16 is properly positioned with extension bar 15A and an angled
elongated
member 10A, which forms an inverted "Z" shape. In Fig. 1 F, elongated members
l 0A
and lOB are directly attached without use of a cross bar, but hook 16 is
properly
positioned to be past the scaffold railing by an angled elongated member 10A.
Additionally, Fig. 1 G shows yet another embodiment that is similar to the
apparatus of
Fig. lA, but has a shorter cross bar and an angled elongated member 10A.
Lastly, Fig.
I H shows an example of the apparatus in which member l OB is angled to offset
Distance D and clamped to railings 30A and B of a frame and brace type
scaffold with
clamps 14A and B. Member l0A is the extended in a vertical direction, on which
hook
16 is mounted. Other embodiments can also be used with the present invention,
so long
as one of the following occurs: a) the apparatus extends past the inner
portion of the
scaffold railing; b) the apparatus is offset in an amount greater than
Distance D, c) the
apparatus is offset by a distance of between about 1 inch (about 2.54 cm) and
about 12
inches (about 30.5 cm); or c) the apparatus is angled by an amount between
about 145
degrees and about 180 degrees in relation to its base or point of attachment
to the
scaffold.
Hence, simply put, the present invention involves having at least one
elongated
member having a device for engaging the safety line, and at least one
attachment for
securing the elongated member to the scaffold, such that the device, when
installed on
the scaffold, extends past the innermost portion of the scaffold railing.
Figs. 1 D-1 H
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simply illustrate various designs to secure the apparatus to the scaffold and,
at the same
time, properly position the device for engaging the safety line, as described
herein.
One embodiment of the safety scaffold system is shown in Figs. 2A and 2B.
Although a set of four scaffold safety apparatuses 20 of Fig. lA-C is used in
this
instance, more or less safety apparatuses can be used to accomplish the task
of securing
an individual on a scaffold and allowing the individual to walk across more
than one
scaffold section 46 without having to disengage. In Figs. 2A and B, elongated
member
lOB of each apparatus is secured to scaffold railing 30A by clamp 14A and B.
Hook 16
is positioned past inside scaffold railing 30B. Safety line 22 is treaded
through hook 16
of each apparatus 20, and then double looped, or looped around and secured to
winch
32. Generally, the safety line should be tightened to withstand a force of an
accidental
fall of at least one person, e.g., in an amount between about 5000 lbs. (
2267.96
kilograms) and about 20,000 lbs. (9,071.85 kilograms). This can be
accomplished by
methods known in the art for securely attaching two ends of a cable or safety
line,
including, for example, using a come-a-long, or a winch (e.g., manual or
electronic) to
tighten the line. To assist on in tightening the safety line, the ends of the
safety lines can
be looped and hooked on to the come-a-long or winch device, and then secured.
After
the safety line is double-looped, it can be reattached to itself, secured with
a device,
attached to the safety apparatus or to the scaffold. Attaching the ends of the
line can be
accomplished with a cable attachment (e.g., a cable vice, a cable clamp, a
cable grip).
The line can be looped around the hook (e.g., device for engaging the safety
line), or
with a pulley or cable block, similar to a clothes drying line. This double
looping allows
a person to secure oneself to the safety line 22 with lanyard 26 via lanyard
hook 27. As
the person moves about the scaffold, lanyard hook 27 avoids elongated member
l0A and
hook 16 thereby allowing the person to move freely.
Figs. 3A-C show the present invention, as installed on a frame and brace type
scaffold. In the front view, shown in Fig. 3A, safety scaffold apparatus 20 is
installed at
the beginning and/or end of each scaffold section 46. Apparatus 20 is clamped
to
scaffold railing 30A with clamps 14A and B on the lower level of the scaffold.
Hook 16
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engages safety line 22, above the level to which member lOB is attached. More
clearly
seen in the side view, Fig. 3B, member IOA extends past the inner scaffold
railing 30B.
In this figure, the scaffold railing is shown in the level below the level on
which the
safety line is being used. The present invention can be installed on the upper
most level
of a scaffold, a lower level of a scaffold, or any level in between. Since the
system's
design involves having a safety line installed on the inside of the innermost
portion of
the scaffold railing, e.g., inner scaffold railing 30B, then the present
invention can be
used while stacking another scaffold level, or simply working on any level,
including a
mid-level or lower-level.
In particular, the present invention involves methods for safely erecting a
scaffold. The steps of the method include erecting a first (e.g., ground)
scaffold level,
securing the safety system of the present invention to the erected scaffold
level, securing
one or more persons to the safety line of the safety system (e.g., engaging
the lanyard to
the safety line), and erecting a second scaffold level while engaged to the
safety line.
The method can further include repeating these steps to erect additional
levels of
scaffolds. After installing the next scaffold level, the person can remain
tied off e.g., to
the safety system on the current level, while installing a second safety
system next level,
and so on.
The bird's eye view, Fig. 3C, of the safety system shows a person wearing
harness 24 and connected to safety line 22 with lanyard 26. Safety line 22 is
threaded
through hook 16 of each apparatus and doubled looped. The ends of safety line
22 are
tightened to withstand the force of an accidental fall, and reattached with
winch 32.
This double looping of the safety line allows a person to move across more
than one
scaffold section 46 without having to disengage.
Several types of devices can be used to secure a person to the safety line so
long
as the person is safely tied off to the safety line. Harness systems or body-
belt systems
can be used. A harness system, referred to herein, refers to a harness and
lanyard
configuration, and a body-belt system includes a body-belt and lanyard.
Similarly,
many types of lanyards exist and can be used with the present invention to
engage the
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safety line, and several devices, such as lanyard hooks, exist to attach the
lanyard to the
safety line. Harnesses, body-belts, and lanyards are known in the art and are
commercially available for use with the present invention. Additionally,
harnesses,
body-belts, lanyards and similar systems that are developed in the future can
be used as
well.
A safety line can be made of cable, rope or other suitable material. The
safety
line can be of various gauges, thicknesses and/or lengths so long as the line
has a
sufficient gauge to withstand the force of an accidental fall of one or more
persons, and
so long the line has a length sufficient to be double looped, as described
herein. The
force of an accidental fall is measured by tests known in the art. The weight
that the
apparatus can withstand ranges from about 5000 lbs. ( 2267.96 kilograms) and
about
20,000 lbs. (9,071.85 kilograms). The length of the safety line depends on the
number
of apparatuses used in the system and the distance they are spaced apart.
Safety lines
that known in the art or those later developed can be used. Safety lines can
be obtained
from a number of manufacturers, including, e.g., from Spider , a division of
SafeWorks, LLC (Tukwila, Washington).
Figs. 4A-4C show the safety scaffold system installed on a cup-lock type
scaffold. The safety scaffold system of present invention is not limited to a
particular
type of scaffold, and can be installed on many types of scaffold including,
for example,
frame and brace type scaffolds, cup lock type scaffolds, quick erect system
scaffolds,
tube and clamp system scaffolds, systems scaffolds, or any combination
thereof.
Scaffolds are known in the art and can be obtained from a number of
manufacturers
including, e.g., Vanguard manufacturing Inc. (New Ipswich, New Hampshire), or
Edge
International (Laguna Niguel, California). The present invention can be
installed on
scaffolds that are known in the art, or those later developed. The cup lock
type scaffold
uses a locking mechanism to secure the ends of vertical and horizontal members
of a
scaffold, as shown, e.g., in U.S. Patent No. 5,560,730. Some scaffolds,
including the
cup lock type scaffold, do not have both outer and inner scaffold railings 30A
and 30B,
as shown with the frame and brace type scaffold in Fig. 313, but has a single
scaffold
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railing at this position, such as scaffold railing 30C, shown in Figs. 4A and
B. As
referenced herein, when describing the position of the device for engaging the
safety
line as being past the inner most portion of the scaffold railing, in this
case, refers to
extending past the scaffold railing 30C. When referring to a scaffold having a
double
railing (e.g., an outer and inner railing as in scaffold railing 30A and 30B
in the frame
and brace type scaffold shown in Figs. 3A-C), the position of the device for
engaging
the safety line extends beyond the innermost portion of the vertical railing,
namely past
scaffold railing 30B. Generally, the device for engaging the safety line
extends past the
inner portion of the scaffold structure so that the line can be positioned to
allow one to
walk freely along more than one scaffold sections. Safety scaffold apparatus
20 is
secured with clamps 14A and B to scaffold railing 30C to be below the scaffold
level,
and member 10A is positioned to be above the scaffold level. Fig. 4C shows
that hooks
16 of each apparatus 20 is positioned past scaffold railing 30C, as described
herein, and
the safety line is secured and double looped, also as further described
herein.
Figs. 3A-C and 4A-C illustrate that the present invention can be installed and
used on various types of scaffolds, and is not limited to the particular
scaffold being
used.
Another embodiment of the present invention is a scaffold structure having the
safety features of the present invention. For example, a type of scaffold can
have a
member that integrates with the scaffold system, and also has the elements of
the present
invention (e.g., more than one device for engaging a safety line, a safety
line that is
engaged to the device and double looped, and an attachment to secure the
device to the
scaffold). A vertical member of a scaffold can have an elongated member that
simply
extends past the inner most portion of the scaffold railing, and a device for
engaging a
safety line can be attached to the end of the elongated member. The safety
line can be
treaded through the device, e.g., a hook and then double looped as described
herein.
Similarly, the present invention embodies scaffold accessories, e.g., as shown
for the
cup lock system, that has a member having an end that interlocks with the
scaffold
system. The other end of the member can have, e.g., the device for engaging
the safety
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line that extends beyond the innermost portion of the scaffold and the safety
line can
then be installed in accordance with the present invention.
The present invention also includes methods for safely using a scaffold. The
steps of the method include engaging a person to the safety line of the safety
scaffold
system, and moving across one or more scaffold sections without disengaging
the safety
line. To engage a person to the safety line, in one embodiment, one can put on
a harness
and attach a lanyard to it. The hook on a lanyard can engage the outer portion
of the
double looped safety line of the safety scaffold system of the present
invention.
EXEMPLIFICATION
Example 1: Construction of the safety scaffold apparatus
The apparatus shown in Fig. lA-C was constructed from two elongated members
and a cross bar. These parts were welded together so that the elongated
members were
essentially parallel. One elongated member has a device for securing a safety
line,
namely a hook, and the other elongated member has an attachment for securing
the
safety device to the scaffold, namely two clamps. The elongated members and
cross bar
were reinforced with diagonal supports. The elongated member having the hook
measures about 34 inches, and the elongated member having the clamps is about
32
inches in length. One clamp is positioned about 6 inches from the top of the
elongated
member, and the other clamp is positioned about 28 inches from the top of the
same
elongated member. The cross bar is approximately 11 inches in length. The
elongated
members and cross bar have a diameter of about 1 5/8th inches, and are made
from steel.
The hook, which is about 4 inches in length and 2 inches in width, was
attached with a
swivel attachment, and the clamps were attached with bolts. The hook was
purchased
froin Spider , a division of SafeWorks, LLC (Tukwila, Washington) (model no.
701283-1) and is further described by U.S. Patent Nos. 4,528,728 and
4,434,536. The
clamps were obtained from Safway Services, Inc. (Waukesha, Wisconsin) (model
no.CRAL2).
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Example 2: Use of the safety scaffold apparatus on a frame & brace type
scaffold
A series of four apparatuses, constructed as described in Example 1, were
installed on a tube and clamp type scaffold (Lynn-Lad Group, LTD. (Lynn,
Massachusetts)). Once the ground level of the scaffold was set-up, each of the
apparatuses was clamped to a vertical member of the scaffold, and positioned
so that the
elongated member having the hook was placed above the scaffold level to which
the
apparatus was clamped. The hook attached to the elongated member extended past
the
innermost portion of the scaffold railing underneath, which in this case was
the inner
railing of the tube and clamp system. The safety line was threaded through
each hook
and double looped and reattached to itself. The line was tightened and the
ends of the
line were held in place using a come-a-long device. A person, having a harness
and
lanyard, then engaged the lanyard hook to the safety line. The person then
proceeded to
attach the next scaffold level and install all the vertical and horizontal
members of the
next scaffold level without having to disengage and/or re-engage the safety
line. The
person repeated these steps to erect a multi-level scaffold.
Example 3: Use of the safety scaffold apparatus on a cup lock type scaffold
A series of four apparatuses, constructed in Example 1, were installed on a
cup
lock type scaffold (Lynn-Lad Group, LTD. (Lynn, Massachusetts)). Once the
ground
level of the scaffold was set-up, each of the apparatuses was clamped to a
vertical
member of the scaffold, and positioned so that the elongated member having the
hook
was placed above the scaffold level to which the apparatus was clamped. The
cup lock
type scaffold does not have a double scaffold railing; rather, it has a single
vertical
member at each support. Hence, the hook attached to the elongated member
extended
past the single vertical scaffold railing underneath. The safety line was
threaded through
each hook and double looped. The line was tightened and secured using a come-a-
long
device. A person, having a harness and lanyard, then engaged the lanyard hook
to the
safety line. The person then proceeded to attach the next scaffold level and
install the
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vertical and horizontal members of the next scaffold level without having to
disengage
and/or re-engage the safety line. The person repeated these steps to erect a
multi-level
scaffold.
The relevant teachings of all the references, patents and/or patent
applications
cited herein are incorporated herein by reference in their entirety.
While this invention has been particularly shown and described with references
to
preferred embodiments thereof, it will be understood by those skilled in the
art that
various changes in form and details may be made therein without departing from
the
scope of the invention encompassed by the appended claims.
