Note: Descriptions are shown in the official language in which they were submitted.
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OUICK CONNECT BREAK-AWAY TOOL TETHER
This invention is in the field of tools and like articles, and in particular
systems for
retaining such articles in attachment to a user's body.
BACKGROUND
For safety reasons, especially when working above other personnel, tools are
often
required to be tethered to the operator to prevent such tools from falling and
injuring
1o people below. Such tethers attach to the wearer at one end and to the tool
at the other
such that if the tool is dropped, it will fall only until the tether is at its
maximum length.
Such tethers are disclosed in United States Patent Numbers 6,776,317 to Parker
and
6,299,040 to Matins. The tethers there disclosed both include a resilient
portion,
is provided by an elastic cord inside a flexible but non-resilient sleeve that
bunches ug when
the elastic cord retracts, and extends to a maximum length when the cord
extends. Thus a
tool attached to the tether will initially stretch the elastic cord, slowing
the fall, and then
when the non-resilient sleeve is fully extended, the fall will be stopped.
Thus the shock
force on the operator from a falling tool is reduced.
zo
Alternatively the tether can comprises a coil as disclosed in United States
Patent Number
6,530,131 to Hopkins, or a cord attached to the wearer's wrist as disclosed in
United
States Patent Number 6,216,319 to Elkins. By attaching the cord to the wrist,
the length
required is very short compared to other tethers that attach to the general
area of the
25 operator's torso. It is however not possible to lay the tool down, or
deposit same in a tool
belt, to free the hand from the tool when it is desired to even briefly use
the hand for
another purpose.
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When changing tools, it is necessary to remove the tether from the first tool
and reattach
it to the second tool. Typically the tool is attached by a looped cord or
strap as disclosed
in the Parker and Matias devices, or a tie as disclosed in the Hopkins device.
A separate
tether can be provided for each tool that will be used, however the tethers
often become
s tangled when changing tools, interfering with operation of the tools.
Alternatively the Elkins device discloses tool receptacles sized to
accommodate various
tools, and including an eyelet. A clasp is mounted on the end of the cord for
attachment
to the eyelet such that the receptacles holding the different tools can be
attached to the
to cord or detached as the tools in the receptacles are being used or not
used. The
receptacles must be sized to accommodate each tool, and thus have limited
versatility
compared to the looped cord of Parker which can be tightened to hold a wide
variety of
tools.
1 s While improving safety for others, such prior art tethers can be hazardous
to the user. In
some applications the tool can be caught in moving machinery, or jammed in a
falling
object, and the user can be dragged into the machine, or off a scaffold or the
like. Matias
addresses this hazard by providing a tear-away portion at the end of the
tether where it is
attached to the user, such that when an excessive force is exerted the tether
will separate
2o from the wearer and allow the tool and tether to fall away_
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a tool tether for securing
tools and the
25 like to a worker that overcomes pmblems in the prior art.
The present invention provides, in a first embodiment, a tool tether apparatus
comprising
a quick coupler comprising a first coupler portion and a second coupler
portion operative
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to releasably engage the first coupler portion. A first tether portion has a
user end
adapted for attachment to a user and a connection end attached to the first
coupler portion
of the quick coupler, and a second tether portion has a tool end adapted for
attachment to
a tool and a connection end attached to the second coupler portion of the
quick coupler.
s At least one of the first and second tether portions is resilient, and the
quick coupler is
configured to break apart when a force exceeding a break-away force is exerted
on the
quick coupler.
The present invention provides, in a second embodiment, a tool tethering
system
1o comprising a quick coupler comprising a first coupler portion and a
plurality of second
coupler portions each operative to releasably engage the first coupler
portion. A resilient
first tether portion has a user end adapted for attachment to a user and a
connection end
attached to the first coupler portion of the quick coupler. The first tether
portion is
extendable from a relaxed length to a maximum length in response to a force
exerted
is thereon that is less than a break-away force. A plurality of substantially
non-resilient
second tether portions each has a tool end adapted for attachment to a tool
and a
connection end attached to one of the plurality of second coupler portions of
the quick
coupler such that each second tether portion can be connected by the quick
coupler to the
first tether portion. The quick coupler is configured to break apart when a
farce
20 exceeding the break-away force is exerted on the quick coupler.
The present invention provides, in a second embodiment, a method of tethering
an
operative tool selected from a plurality of available tools to a user, the
method
comprising providing a quick coupler comprising a first coupler portion and a
plurality of
25 second coupler portions each operative to releasably engage the first
coupler portion;
providing a resilient first tether portion having a user end attached to the
user and
attaching a connection end to the first coupler portion of the quick coupler,
wherein the
first tether portion is extendable from a relaxed length to a maximum length
in response
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to a force exerted thereon that is less than a break-away force; providing a
plurality of
substantially non-resilient second tether portions each having a tool end
adapted for
attachment to an available tool and a connection end attached to one of the
plurality of
second coupler portions of the quick coupler such that each second tether
portion can be
connected by the quick coupler to the first tether portion; configuring the
quick coupler
to break apart when a force exceeding the break-away force is exerted on the
quick
coupler; attaching a tool end of a second tether portion to each available
tool; and from
the plurality of available tools, selecting an operative tool attached to a
corresponding
second tether portion and engaging the second coupler portion attached thereto
with the
first coupler portion.
The resilient tether reduces the shock forces on the quick coupler when a toot
is dropped,
such that the break-away force is not exceeded, however if the tool is caught,
for example
in rotating machinery or in a falling object, the quick coupler will break
apart so that the
user is not dragged along with the tool. The second tether portions can be
made
relatively short such that when tethering one of a plurality of toots, a
second tether
portion can be attached to each tool in a tool belt or pouch, and then when a
particular
tool is being used the s~ond coupler portion of the corresponding second
tether portion
is simply engaged in the first coupler portion attached to the fast tether
portion which in
2o turn is attached to the user. The second tether portions are also
relatively simple and
inexpensive compared to the resilient first tether portion, and so a tethering
system can be
economically provided comprising a single first tether section and any
required number
of the second tether portions. When worn or damaged, the second tether
portions can be
discarded and replaced.
DESCRIPTION OF THE DRAWINGS:
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While the invention is claimed in the concluding portions hereof, preferred
embodiments
are provided in the accompanying detailed description which may be best
understood in
conjunction with the accompanying diagrams where like parts in each of the
several
diagrams are labeled with like numbers, and where:
Fig. 1 is a tope view of an embodiment of a tool tether apparatus of the
invention
showing the first tether portion at its relaxed length and disconnected from
the
second tether portion;
Fig. 2 is a top view of the first tether portion of the embodiment of Fig. 1
at its
maximum length;
Fig. 3 is a top view of the embodiment of Fig. 1 showing the first tether
portion at
its relaxed length and connected to the second tether portion by the quick
coupler;
~5
Fig. 4 is a top view of the embodiment of Fig. 1 showing the loop in the
second
tether portion open for attachment to a tool;
Fig. 5 is a top view of the embodiment of Fig. 1 showing the loop in the
second
20 tether portion closed for tightening to a tool, and with the first tether
portion at its
maximum length;
Fig. 6 is a side view of a tool tethering system using a single first tether
portion
and a plurality of second tether portions of the embodiment of Fig. 1.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS:
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Figs. 1 - 5 schematically illustrate a tool tether apparatus 1 of the
invention. The
apparatus 1 comprises a quick coupler 3 with a first coupler portion 5 and a
second
coupler portion 7 operative to releasably engage the first coupler portion 5.
A first tether
portion 9 has a user end 11 adapted for attachment to a user and a connection
end 13
attached to the first coupler portion 5 of the quick coupler 3. A second
tether portion 15
has a tool end 17 adapted for attachment to a tool and a connection end 19
attached to the
second coupler portion 7 of the quick coupler 3.
The quick coupler 3 is configured to break apart when a force exceeding a
break-away
to force is exerted on the quick coupler. Although other known mechanisms,
properly
selected, could provide the required quick coupler, the illustrated quick
coupler 3 is a
common nylon clip where the first coupler portion 5 comprises a male end that
is
releasably engaged in a corresponding female end that provides the second
coupler
portion 7. In order to prevent a tethered tool from being caught and dragging
the user
into machinery, or dragging him off a scafiFold or the like, the quick coupler
3 is sized
such that the break-away force is about 60 - 70 pounds. With a quick coupler 3
as
illustrated it has been found that when the force on the tether apparatus 1
exceeds that
break-away force, the first and second coupler portions 5, 7 will either
disengage or,
more often one of the first and second coupler portions 5, 7 will fracture
such that the
2o first and second tether portions 9, IS become disconnected.
In order to use a tethered tool, the tether must be long enough to reach from
attachment
point of the user end 11 of the first tether portion 9 to the user to the end
of the user's
extended arm, as illustrated in Fig. 6. While the tether apparatus 1 could
simply be made
long enough to allow this reach, excessive tether length increases the
occurrence of
tangling the tether_ To reduce the required length of the tether apparatus I,
the tether
apparatus 1 is resilient. In addition to reducing the length of the apparatus
1, the
resiliency also reduces the shock loading on the quick coupler 3. A heavy tool
falling
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from the user's hand and being jerked to a halt by the tether apparatus 1
could cause a
force to be exerted on the Quick coupler 3 that exceeds the break-away force.
By gently
breaking the tool's fall by stretching and exerting an increasing force as it
lengthens, the
tether apparatus reduces the force exerted on the quick coupler 3, providing
more secure
s tool tethering and reducing the risk that the break-away quick coupler 3
might separate
when it should be stopping a tool from falling.
In the illustrated tether apparatus 1 the fwst tether portion 9 is resilient
and the second
tether portion 15 is substantially non-resilient. The first tether portion 9
comprises an
to elastic cord inside a flexible but non-resilient sleeve that bunches up
when the elastic
cord retracts, and extends to a maximum length when the cord extends. Thus the
first
tether portion 9 is extendable from a relaxed length, as illustrated in Fig. 1
to a maximum
Iength as illustrated in Fig. 2 in response to a force exerted thereon that is
less than the
break-away force. Thus in use the tether apparatus 1 will stretch to its
maximum length
15 as illustrated in Figs. 5 and 6 in response to a normal reaching force,
less than the break-
away force, exerted thereon by the user, and then if for some reason the force
increases to
the break-away force, the quick coupler 3 will break apart, either by
disengaging or
fracturing in the illustrated embodiment, or by some similar means in other
contemplated
embodiments.
In the illustrated embodiment, the tool end 17 of the second tether portion 15
comprises a
cord 21 forming a loop 23 and a cord grip 25 slidable on the cord 21 to open
the loop 21,
as illustrated in Fig. 4 to fit same over a tool, and then slidable to the
position of Fig. 3
and adapted to releasably engage the cord 21 to tighten the loop 23 around a
tool. The
cord 21 forming the Ioop 23 also passes through a retainer 27, provided by a
short plastic
tube or the like, such that the cord grip 25 is prevented from sliding off the
end of the
loop. The user end 11 of the first tether portion 9 is attached to a hook 29
that can be
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opened or closed to releasably engage with an anchor worn by the user, such as
a ring on
a harness, belt, or the like:
The second tether portion 15 is substantially non-resilient such that same
retains
substantially the same length regardless of the force exerted on it, up to a
breaking force
which is of course also greater than the break-away force. In the illustrated
embodiment
the first portion 9 has a relaxed length that is slightly longer than the
length of the second
tether portion 15.
i0 The tether apparatus 1 can conveniently provide a tether system for
tethering an operative
tool selected from a plurality of available tools to a user, as illustrated in
Fig. 6. The first
tether portion 9 has a length that is substantially equal to or greater than a
length of the
second tether portion 15. A relatively shorter second tether portion 15 is
attached at the
tool end thereof to each of an available plurality of tools illustrated as a
drill 31, hammer
33, and screwdriver 35. In Fig. 6 a second tether portion 15A is attached to
the drill 31,
second tether portion 15B is attached to the hammer 33, and second tether
portion 15C is
attached to the screwdriver 35. The second coupler portions 7 at the
connection ends of
each second tether portions 15A, ISB, 15C are each engagable with the first
coupler
portion 5 on the connection end of the first tether portion 9 that is anchored
to the user.
In Fig. 6 the user has selected the drill 31 as the operative tool from the
plurality of
available tools, and has attached the corresponding second tether portion 15A
by
engaging the second coupler portion 7 attached thereto with the first coupler
portion 5.
Tlte user can readily change the operative tool by disengaging the second
coupler portion
7 from the first coupler portion 9 and engaging with the first coupler portion
a second
coupler portion 7 attached to a different selected one of the available tools.
The second
tether portions attached to idle tools simply hang beside the user where they
are readily
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available when required. The relatively shorter and non-resilient second
tether portions
15 are subject to tangling to a lesser degree than a full length tether. The
second tether
portions 15 are relatively simple and economical compare to the first tether
portion 9,
and can be replaced as required if damaged or worn while maintaining use of
the more
costly first tether portion.
The foregoing is considered as illustrative only of the principles of the
invention.
Further, since numerous changes and modifications will readily occur to those
skilled in
the art, it is not desired to limit the invention to the exact construction
and operation
to shown and described, and accordingly, alI such suitable changes or
modifications in
structure or operation which may be resorted to are intended to fall within
the scope of
the claimed invention.
