U.S. patent application number 12/508061 was filed with the patent office on 2010-01-28 for messenger clamp.
Invention is credited to BRIAN BOISCLAIR.
Application Number | 20100018014 12/508061 |
Document ID | / |
Family ID | 41567327 |
Filed Date | 2010-01-28 |
United States Patent
Application |
20100018014 |
Kind Code |
A1 |
BOISCLAIR; BRIAN |
January 28, 2010 |
MESSENGER CLAMP
Abstract
Messenger clamps can be formed from two messenger clamp halves.
Messenger clamps and messenger clamp halves can include break away
portions, which allow a messenger wire to fall when subjected to
high impact forces such as a tree falling on the messenger wire. A
messenger clamp half for use in forming a messenger clamp can
include an inside face having a first clamping groove and a second
clamping groove, and an outside face having at least one fault
groove. A break away portion of the messenger clamp half can
include one of the clamping grooves, and can further includes at
least a portion of the fault groove.
Inventors: |
BOISCLAIR; BRIAN;
(Goffstown, NH) |
Correspondence
Address: |
PATENT GROUP;C/O DLA PIPER US LLP
203 N. LASALLE ST., SUITE 1900
CHICAGO
IL
60601
US
|
Family ID: |
41567327 |
Appl. No.: |
12/508061 |
Filed: |
July 23, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61082986 |
Jul 23, 2008 |
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Current U.S.
Class: |
24/526 ;
24/522 |
Current CPC
Class: |
Y10T 24/44607 20150115;
Y10T 24/44034 20150115; H02G 7/08 20130101; Y10T 24/44573
20150115 |
Class at
Publication: |
24/526 ;
24/522 |
International
Class: |
A44B 21/00 20060101
A44B021/00 |
Claims
1. A messenger clamp half for use in forming a messenger clamp, the
messenger clamp half comprising: an inside face having a first
clamping groove and a second clamping groove, an outside face
having at least one fault groove; and at least one break away
portion that includes the first clamping groove or the second
clamping groove, and further includes at least a portion of the
fault groove.
2. The messenger clamp half of claim 1, wherein the outside face
includes a first fault groove and a second fault groove.
3. The messenger clamp half of claim 2, wherein the messenger clamp
half includes a first break away portion that includes the first
clamping groove and at least a portion of the first fault groove,
and a second break away portion that includes the second clamping
groove and at least a portion of the second fault groove.
4. The messenger clamp half of claim 1, further comprising a bolt
hole.
5. The messenger clamp half of claim 1, wherein the inside face
includes one or more mating features adapted to mate with
corresponding mating features on a second messenger clamp half.
6. The messenger clamp half of claim 1, wherein the fault groove
has a V-shaped cross section.
7. The messenger clamp half of claim 1, wherein the fault groove
has an angle of about 45.degree..
8. The messenger clamp half of claim 1, wherein the first clamping
groove and the second clamping groove each have a length that
traverses the messenger clamp half, and at least one of the first
clamping groove or the second clamping groove is arched along the
length and bows inwardly towards the center of the inner face.
9. The messenger clamp half of claim 1, wherein the first clamping
groove and the second clamping groove each have a length that
traverses the messenger clamp half, and at least one of the first
clamping groove or the second clamping groove is straight along the
length.
10. The messenger clamp half of claim 1, wherein the first clamping
groove and the second clamping groove each have an arcuate
cross-section.
11. The messenger clamp half of claim 10, wherein the arcuate cross
section of the second clamping groove is a different size than the
arcuate cross section of the first clamping groove.
12. The messenger clamp half of claim 1, wherein the fault groove
has a thickness that is less than a thickness of the messenger
clamp half as measured from the outside face to the inside face,
and the thickness is selected to provide sufficient structural
strength to maintain a messenger clamp under normal loading
conditions.
13. The messenger clamp half of claim 12, wherein the thickness of
the fault groove is selected to provide structural failure when
the, messenger clamp half is subjected to break away forces.
14. A messenger clamp comprising: a first messenger clamp half; and
a second messenger clamp half; wherein the first messenger clamp
half includes: an inside face having a first clamping groove and a
second clamping groove; an outside face having at least one fault
groove; and at least one break away portion that includes the first
clamping groove or the second clamping groove and further includes
at least a portion of the fault groove.
15. The messenger clamp of claim 14, wherein the second messenger
clamp half includes: an inside face having a first clamping groove
and a second clamping groove, an outside face having at least one
fault groove; and at least one break away portion that includes the
first clamping groove or the second clamping groove, and further
includes at least a portion of the fault groove.
16. The messenger clamp of claim 15, wherein the first and second
messenger clamp halves each further comprise a bolt hole.
17. The messenger clamp of claim 16, wherein the messenger clamp is
installed in an orientation where the first clamping grooves of
each messenger clamp half below the bolt hole, and a messenger wife
is retained by the first clamping grooves of the first and second
messenger clamp halves.
18. The messenger clamp half of claim 14, wherein the fault groove
has a thickness that is less than a thickness of the messenger
clamp half as measured from the outside face to the inside face,
and the thickness is selected to provide sufficient structural
strength to maintain a messenger clamp under normal loading
conditions.
19. The messenger clamp half of claim 18, wherein the thickness of
the fault groove is selected to provide structural failure when the
messenger clamp half is subjected to break away forces.
20. A messenger clamp comprising: a first messenger clamp half
including a bolt hole; and a second messenger clamp half including
a bolt hole; wherein the first messenger clamp half further
includes: an inside face having a first clamping groove and a
second clamping groove; an outside face having at least one fault
groove that is located below the bolt hole when the messenger clamp
is installed; and at least one break away portion that includes the
first clamping groove or the second clamping groove and further
includes at least a portion of the fault groove.
Description
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application Ser. No. 61/082,986, filed on Jul. 23, 2008, currently
pending.
BACKGROUND
[0002] This disclosure relates to messenger clamps utilized with
messenger wires for pole-mounted power distribution cables. More
specifically, this disclosure relates to messenger clamps having a
break away feature.
[0003] Utility wires that are attached to utility poles generally
include a power distribution line, which can include several power
conducting cables, and a messenger wire. An entire run of a power
distribution line encompasses the overall distance over which the
power conducting cables are to be installed at one time, with
individual spans being the distance from one utility pole to the
next.
[0004] A messenger wire is generally put in position between spans
to provide support to the power distribution line. For example, a
messenger wire can be formed from multiple strands, including
aluminum-clad steel strands, or a combination of aluminum-clad
steel strands and aluminum strands. Messenger wires can include,
for example, five, seven, or twelve strands, and can have a total
messenger wire diameter from about 0.385 inches to about 0.722
inches. A messenger wire can be lashed to the power distribution
line by heavy binding wire. The messenger wire is separated from
the power distribution line at the utility poles, where it can be
attached directly to the pole, or can be attached to a bracket on
the utility pole that utilizes a messenger clamp, to provide
vertical support for the power distribution line. Generally, the
messenger wire is secured to the top of the clamp, and the
conductors of the power distribution line hang below the clamp to
which the messenger wire is secured.
BRIEF SUMMARY
[0005] Messenger clamps utilized with messenger wires for
pole-mounted power distribution lines are provided herein that
include a break away feature. The messenger clamps can retain a
messenger Wire under normal loading conditions, and a portion of
the messenger clamp can break away under heavy impact loading, such
as a tree or branch falling onto the line, to release the messenger
wire arid reduce the likelihood of, or avoid, the breakage of the
utility pole.
[0006] In one aspect, a messenger clamp half for use in forming a
messenger clamp is provided that includes an inside face having a
first clamping groove and a second clamping groove, an outside face
having at least one fault groove, and at least one break away
portion. The break away portion can include the first clamping
groove or the second clamping groove, and further includes at least
a portion of the fault groove.
[0007] In another aspect, a messenger clamp is provided that
includes a first messenger clamp half and a second messenger clamp
half. The first messenger clamp half includes an inside face having
a first clamping groove and a second clamping groove, an outside
face having at least one fault groove, and at least one break away
portion. The break away portion includes the first clamping groove
or the second clamping groove and further includes at least a
portion of the fault groove.
[0008] In a third aspect, a messenger clamp is provided that
includes a first messenger clamp half including a bolt hole and a
second messenger clamp half including a bolt hole. The first
messenger clamp half further includes an inside face having a first
clamping groove and a second clamping groove, an outside face
having at least one fault groove that is located below the bolt
hole when the messenger clamp is installed, arid at least one break
away portion. The break away portion includes the first clamping
groove or the second clamping groove and further includes at least
a portion of the fault groove.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0009] Specific examples have been chosen for purposes of
illustration and description, and are shown in the drawings
attached hereto, forming a part of the specification.
[0010] FIG. 1 illustrates a messenger clamp connected to a tangent
bracket on a utility pole, with a messenger wire attached
thereto.
[0011] FIG. 2 is aback perspective view of one example of a
messenger clamp half.
[0012] FIG. 3 is an end view of the messenger clamp half of FIG.
2.
[0013] FIG. 4 is a back view of the messenger clamp half of FIGS. 2
and 3.
[0014] FIG. 5 is an end view of a second example of a messenger
clamp half.
[0015] FIG. 6 is a back view of the messenger clamp half of FIG.
5.
[0016] FIG. 7 is a front perspective view of the messenger clamp
half of FIGS. 5 and 6.
DETAILED DESCRIPTION
[0017] This disclosure relates to messenger clamps utilized in
spacer cable systems for pole-mounted power distribution lines.
More particularly, messenger clamps having at least one break away
portion are disclosed herein, which allow a messenger wire to
detach from a utility pole under certain conditions.
[0018] As illustrated in FIG. 1, a messenger clamp 100 can be
attached to a tangent bracket 200 on a utility pole 300. A
messenger wire 400 can be retained by the messenger clamp 100, and
can thus be connected to the utility pole 300 via the messenger
clamp 100 and the tangent bracket 200. Preferably, the messenger
wire 400 is attached to the bottom of the messenger clamp 100, and
hangs under the bolt 500 which secures the messenger clamp 100 to
the tangent bracket 200. This configuration differs from the
conventional configuration utilized for a messenger wire, where the
cable is attached to the top of the clamp.
[0019] A messenger clamp 100 can be formed from two messenger clamp
halves, and at least one of the messenger clamp halves can include
at least one break away portion. Under normal loading conditions,
the messenger clamp can retain a messenger wire in clamping grooves
on the messenger clamp halves. The messenger clamp can also retain
the messenger wire under higher than normal loading conditions,
such as severe weather However, the messenger clamp 100 can allow
the messenger wire 400 to detach from its connection to the utility
pole 300 under certain conditions that result in break away forces
and cause the break away portion of the messenger clamp half to
break away from the messenger clamp 100.
[0020] The amount of force determined to be a break away force can
vary depending upon the conditions under which it is desired that
the break away portion of the messenger clamp 100 will break away.
Break away forces can be created by forces such as instantaneous
load or shock. In some examples, break away forces can be applied
in a downward or horizontal direction at a non-specific angle.
Break away forces can include, for example, high impact forces such
as a tree or large branch falling onto the messenger wire. With
currently utilized messenger clamps, a such high impact force, can
be transferred from the messenger wire to the utility pole, which
can result in the pole breaking. The time and costs associated with
replacing utility poles can be very high, particularly in remote or
back-lot construction areas. The currently disclosed messenger
clamps can break away at a desired location, thus releasing the
messenger wire 400 and preventing the impact forces from being
transferred to the utility pole 300.
[0021] FIGS. 2 through 4 illustrate one example of a messenger
clamp half 102. Messenger clamp half 102 has a inside face 104, a
outside face 106, and a bolt hole 108. The inside face 104 has a
first clamping groove 110, a second clamping groove 112, and one or
more mating features 114a-114d. The outside face 106 has a first
fault groove 116 and a second fault groove 118. The bolt hole 108
can be located in the center of the messenger clamp half. The bolt
hole 108 can be located in the center of the messenger clamp half
with respect to the height or width of the messenger clamp half,
and is preferably located in the center of the messenger clamp half
with respect to the height and width of the messenger clamp
half.
[0022] Messenger clamp half 102 includes at least one break away
portion. A break away portion can be intended to break away when
subjected to break away forces. As illustrated in FIGS. 2 though 4,
messenger clamp half 102 includes a break away portion associated
with each of the first and second clamping grooves 110 and 112. The
first breakaway portion 120 of the messenger clamp half 102
includes first clamping groove 110 and at least a portion of the
first fault groove 116. Likewise, the second breakaway portion 122
of the messenger clamp half 102 includes second clamping groove 112
arid at least a portion of the second fault groove 118.
[0023] The fault grooves 116 and 118 can be designed to provide
structural failure when subjected to a break away force, allowing
their associated break away portions to break away. Thus the amount
of the fault groove that is included in a break away portion of the
messenger clamp half 102 can vary depending upon the design of the
fault groove. For example, the first break away portion 120 can
include about half of the first fault groove 116, less than about
half of the first fault groove 116, or greater than about half of
the first fault groove 116. Similarly, the second break away
portion can include about half of the second fault groove 118, less
than about half of the second fault groove 118, or greater than
about half of the second fault groove 118.
[0024] First clamping groove 110 and second clamping groove 112 can
each have a length that traverses the messenger clamp half 102.
First clamping groove 110 can be straight or arched along the
length of the first clamping groove 110. Similarly, second clamping
groove 112 can be straight or arched along the length of the second
clamping groove 112. As illustrated in FIGS. 2 and 4, first
clamping groove 110 and second clamping groove 112 are each arched
along their respective lengths, so that they bow inwardly towards
the center of the inside face of the messenger clamp half 102,
which is also towards the bolt hole 108 of the messenger clamp half
102.
[0025] First clamping groove 110 and a second clamping groove 112
can each have an arcuate cross-section. The cross-section of first
clamping groove 110 is preferably a different size from the
cross-section of second clamping groove 112, to allow use of the
messenger clamp with a broad range of messenger wire sizes. For
example, first clamping groove 110 can be smaller than second
clamping groove 112, and can have a smaller width and/or radius. In
a preferred embodiment, the first clamping groove 110 can be
utilized to retain messenger wires having a diameter from about 1/2
inch to about 3/4 inches, and second clamping groove 112 can be
utilized to retain messenger wires having a diameter from about
5/16 inches to about 7/16 inches. The messenger clamp can be
oriented on a tangent bracket with either first clamping groove 110
or second clamping groove 112 in the lower position, below the bolt
hole 108, to receive and retain the messenger wire.
[0026] As shown in FIGS. 2 and 3, fault grooves 116 and 118 are
located on the outside face 106 of a messenger clamp half 102. The
messenger clamp half 102 is designed to break along at least one of
the fault grooves, under specified loading parameters, such as when
subjected to a break away force. In practice, the messenger clamp
half 102 can break along the fault groove associated with the
clamping groove that is retaining the messenger wire.
[0027] As shown in FIGS. 2 and 3, fault grooves 116 and 118 are
grooves that traverse the length of the messenger clamp half 102,
and have a V-shaped cross section that is uniform along the length
of the messenger clamp half 102. Fault grooves 116 and 118 could
have any suitable cross-section shape, and can be formed from
notches, grooves, scoring, or any other suitable feature.
Additionally, fault grooves 116 and 118 do not have to be uniform
along the length of the messenger clamp half 102. Fault grooves 116
and 118 can be intermittent along the length of the messenger clamp
half 102.
[0028] FIG. 3 illustrates that the V-shaped cross-section of fault
groove 116 has an angle .alpha., and the V-shaped cross-section of
fault groove 118 has an angle .beta.. The fault grooves 116 and 118
can have any suitable angle. The angles of fault grooves 116 and
118 can be the same or different. In one example, angle .alpha. is
about 45.degree. and angle .beta. is also about 45.degree..
[0029] Fault grooves 116 and 118 each have a thickness that is less
then the total thickness of the messenger clamp half 102 as
measured from the outside face 106 to the inside face 104. For
illustrative purposes, the thickness T.sub.1 of fault groove 116 is
shown in FIG. 3. The thickness of fault groove 118 can be the same
as or different than the thickness T.sub.1 of fault groove 116. The
thickness of each fault groove can be chosen to provide sufficient
structural strength to the messenger clamp to retain a messenger
wire under normal loading conditions, as well as under above
normal, or high loading conditions that are below the desired break
away force, such as severe weather conditions. The thickness of
each fault groove can also be selected to provide structural
failure when subjected to a break away force.
[0030] FIGS. 5 through 7 illustrate one example of a messenger
clamp half 202. Messenger clamp half 202 has a inside face 204, a
outside face 206, and a bolt hole 208. The inside face 204 has a
first clamping groove 210, a second clamping groove 212, and mating
features 214a-214d. Messenger clamp half 202 includes a break away
portion associated with only one of its clamping grooves. The
outside face 206 has a fault groove 216, located at or near one end
of second clamping groove 212. A breakaway portion 218 of the
messenger clamp half 202 includes second clamping groove 212 and at
least a portion of the second fault groove 216.
[0031] As illustrated in FIG. 7, the messenger clamp half 202 can
also include a recessed portion 220. Recessed portion 220 can be
located around the bolt hole 208. As illustrated, recessed portion
220 is circular, and is concentric with bolt hole 208. The recessed
portion 220 can receive a boss on a tangent bracket, such as
tangent bracket 200 illustrated in FIG. 1. The recessed portion 220
can allow the messenger clamp to rotate about the tangent bracket
boss, and can thus adjust in position so that it rests at an angle
that accommodates any change in elevation between utility
poles.
[0032] First clamping groove 210 and second clamping groove 212 can
each have a length that traverses the messenger clamp half 202.
First clamping groove 210 can be straight or arched along its
length. Similarly, second clamping groove 212 can be straight or
arched along its length. As illustrated in FIGS. 5 and 6, first
clamping groove 210 arid second clamping groove 212 are each
straight.
[0033] First clamping groove 210 and a second clamping groove 212
can each have an arcuate cross-section. As illustrated, the
cross-section of first clamping groove 210 can be the same size the
cross-section of second clamping groove 212. Alternatively, the
cross-section of first clamping groove 210 can be a different size
from the cross-section of second clamping groove 212 as discussed
above with respect to messenger clamp half 102.
[0034] The messenger clamp can be oriented on a tangent bracket
with either first clamping groove 210 or second clamping groove 212
in the lower position, below the bolt hole 208, to receive and
retain the messenger wire. As shown in FIGS. 2 and 3, fault groove
216 is located on the outside face 206 of a messenger clamp half
202. The messenger clamp half 202 is designed to break along the
fault groove 216, under specified loading parameters, such as high
impact forces. Thus, in practice, when a messenger clamp is formed
utilizing messenger clamp half 202, and is installed with the
second clamping groove 212 in the lower position such that a
messenger wire is retained in the second clamping groove 212, the
messenger clamp half 202 can break along the fault groove 216 and
allow the messenger wire to fall when the specific loading
parameters are met.
[0035] As shown in FIGS. 5 and 7, fault groove 216 is a groove that
traverses the length of the messenger clamp half 202, and has a
V-shaped cross section that is uniform along the length of the
messenger clamp half 202. Fault groove 216 could have any suitable
cross-section shape, and can be formed from notches, grooves,
scoring, or any other suitable feature. Additionally, fault groove
216 does not have to be uniform along the length of the messenger
clamp half 202. Fault groove 116 can be intermittent along the
length of the messenger clamp half 202. FIG. 5 illustrates that the
V-shaped cross-section of fault groove 116 has an angle .gamma..
The angle .gamma. can be any suitable angle, including, but not
limited to about, 45.degree..
[0036] Fault groove 216 has a thickness T.sub.2 that is less then
the total thickness of the messenger clamp half 202 as measured
from the outside face 206 to the inside face 204. The thickness of
each fault groove can be chosen to provide sufficient structural
strength to the messenger clamp to retain a messenger wire under
normal loading conditions, as well as under high loading conditions
that are below the desired break away forces, such as severe
weather conditions.
[0037] A messenger clamp 100 can be formed by mating two messenger
clamp halves. The two messenger clamp halves can be the same or
different. In one example, two messenger clamp halves 102 as
illustrated in FIGS. 2 through 4 can be mated to form a messenger
clamp. Mating two messenger clamp halves 102 to form a messenger
clamp can be accomplished by bringing together their respective
inside faces 104 and mating features 114a-114d. For example, mating
features 114a and 114d of a first messenger clamp half 102 would
mate with mating features 114b and 114c of a second messenger clamp
half 102. In another example, two messenger clamp halves 202 as
illustrated in FIGS. 5 through 7 can be mated to form a messenger
clamp. Mating two messenger clamp halves 202 to form a messenger
clamp can be accomplished by bringing together their respective
inside faces 204 and mating features 214a-214d. For example, mating
features 214a and 214d of a first messenger clamp half 202 would
mate with mating features 214b and 214c of a second messenger clamp
half 202. With respect to each example, once the two messenger
clamp halves are mated, a bolt can be inserted through the bolt
hole 108 or 208 to attach the messenger clamp to a tangent bracket
on a utility pole. For example, a 5/8 inch bolt or a 3/4 inch bolt,
and also preferably a nut or lock washer, can be utilized to attach
the messenger clamp to a tangent bracket.
[0038] Each half of a messenger clamp can be made of any suitable
material, but is preferably cast ductile iron that has a hot dip
galvanized finish. For example, when two messenger clamp halves 102
or 202 are combined to form a messenger clamp, each messenger clamp
half 102 or 202 can be made of ductile iron that is fabricated from
a sand cast mold and each messenger clamp half 102 or 202 can be
hot dip galvanized after fabrication.
[0039] Messenger clamp halves 102 and 202 can have any suitable
dimensions. In a preferred embodiment, messenger clamp halves 102
and 202 can have a length of about 3.5 inches, and a height of
about 3 and 3/16 inches. A messenger clamp, formed from two
messenger clamp halves, can have any suitable weight, and weight,
for example, about 2.2 pounds.
[0040] In one example, with reference to FIGS. 1 and 2 through 4,
two messenger clamp halves 102 can be mated to form a messenger
clamp 100. The messenger clamp 100 can be installed in an
orientation where the second clamping grooves of each messenger
clamp half are below the bolt hole, and a messenger wire is
retained by the second clamping grooves 112 of the first and second
messenger clamp halves. Thus, as installed, the messenger clamp can
be bolted by bolt 500 to tangent bracket 200 on utility pole 300
such that the two second clamping grooves 112 are in the lower
position, below the bolt, and the messenger wire 400 can be
received and retained by the two second clamping grooves 112. Under
a normal loading conditions, messenger clamp 100 will retain
messenger wire 400 on the utility pole 300. If the messenger wire
400 is subjected to a break away force, such as a force that would
normally cause utility pole 300 to break, the messenger clamp 100
will break at fault groove 118, causing the second breakaway
portion 122 of the messenger clamp, including clamping groove 112
and the messenger wire 400 retained therein, to break off of the
messenger clamp 100 land fall.
[0041] wherein the messenger clamp is installed in an orientation
where the first clamping grooves of each messenger clamp half below
the bolt hole.
[0042] In another example, with reference to FIGS. 1 and 2 through
4, two messenger clamp halves 102 can be mated to form a messenger
clamp 100. The messenger clamp 100 can be installed in an
orientation where the first clamping grooves of each messenger
clamp half are below the bolt hole, and a messenger wire is
retained toy the first clamping grooves 110 of the first and second
messenger clamp halves. Thus, as installed, the messenger clamp 100
can be bolted to tangent bracket 200 on utility pole 300 such that
the two first-clamping grooves 110 are in the lower position, below
the bolt, and the messenger wire 400 can be received and retained
by the two first clamping grooves 110. Under a normal loading
conditions, messenger clamp 100 will retain messenger wire 400 on
the utility pole 300. If the messenger wire 400 is subjected to
high impact loading, such as forces that would normally cause
utility pole 300 to break, the messenger clamp 100 will break at
fault groove 116, causing the first breakaway portion 120 of the
messenger clamp, including clamping groove 110 and the messenger
wire 400 retained therein, to break off of the messenger clamp 100
and fall.
[0043] In a third example, with reference to FIGS. 1 and 5 through
7, two messenger clamp halves 202 can be mated to form a messenger
clamp 100. Messenger clamp 100 can be installed in an orientation
where the second clamping grooves of each messenger clamp half are
below the bolt hole, and a messenger wire is retained by the second
clamping grooves 212 of the first and second messenger clamp
halves. Thus, as installed, the messenger clamp 100 can be bolted
to tangent bracket 200 on utility pole 300 such that the two second
clamping grooves 212 are in the lower position, below the bolt, and
the messenger wire 400 can be received and retained by the two
second clamping grooves 212. Under a normal loading conditions,
messenger clamp 100 will retain messenger wire 400 on the utility
pole 300. If the messenger wire 400 is subjected to high impact
loading, such as forces that would normally cause utility pole 300
to break, the messenger clamp 100 will break at fault groove 216,
causing the first breakaway portion 218 of the messenger clamp,
including clamping groove 212 and the messenger wire 400 retained
therein, to break off of the messenger clamp 100 and fall.
[0044] In a fourth example, with reference to FIGS. 1 and 5 through
7, in areas where it is believed that the break away feature is not
needed, or where there is an intention not to allow the messenger
wire 400 to detach from the utility pole 300, two messenger clamp
halves 202 can be mated to form a messenger clamp 100, which can be
bolted to tangent bracket 200 on utility pole 300 such that the two
first clamping grooves 210 are in the lower position, below the
bolt. A messenger wire 400 can be received and retained by the two
first clamping grooves 210. Under a normal loading conditions,
messenger clamp 100 will retain messenger wire 400 on the utility
pole 300. Because the first clamping grooves 210 do not have a
fault groove associated therewith, the messenger clamp is not
intended to break and release the messenger wire 400 when the
messenger wire 400 is subjected to high impact loading, such as
forces that would normally cause utility pole 300 to break.
[0045] From the foregoing, it will be appreciated that although
specific examples have been described herein for purposes of
illustration, various modifications may be made without deviating
from the spirit or scope of this disclosure. It is therefore
intended that the foregoing detailed description be regarded as
illustrative rather than limiting, and that it be understood that
it is the following claims, including all equivalents, that are
intended to particularly point out and distinctly claim the claimed
subject matter.
* * * * *