U.S. patent application number 13/875002 was filed with the patent office on 2013-09-19 for portable cable puller.
This patent application is currently assigned to Actuant Corporation. The applicant listed for this patent is ACTUANT CORPORATION. Invention is credited to Christian P. Coulis, Anthony W. Gilbert, Edward A. Haase, Patrick J. Radle, Michael A. Schrauth.
Application Number | 20130240807 13/875002 |
Document ID | / |
Family ID | 43379685 |
Filed Date | 2013-09-19 |
United States Patent
Application |
20130240807 |
Kind Code |
A1 |
Radle; Patrick J. ; et
al. |
September 19, 2013 |
Portable Cable Puller
Abstract
A portable apparatus for pulling a cable through a conduit
includes a frame that has a base and caster wheels. The apparatus
further includes a boom that has at least one roller configured to
guide a rope connected to the cable along the boom. The boom also
includes a main boom pivotally connected to the base and an upper
boom pivotally connected to the main boom. A drive unit connects to
the boom and includes a rotatable spool configured to pull the rope
along the boom. The apparatus further includes a lift pivotally
connected to the frame and the boom. The lift is operable to move
the boom relative to the frame.
Inventors: |
Radle; Patrick J.; (Mequon,
WI) ; Schrauth; Michael A.; (De Pere, WI) ;
Coulis; Christian P.; (Sussex, WI) ; Haase; Edward
A.; (South Milwaukee, WI) ; Gilbert; Anthony W.;
(Waukesha, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ACTUANT CORPORATION |
Menomonee Falls |
WI |
US |
|
|
Assignee: |
Actuant Corporation
Menomonee Falls
WI
|
Family ID: |
43379685 |
Appl. No.: |
13/875002 |
Filed: |
May 1, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12825499 |
Jun 29, 2010 |
8434741 |
|
|
13875002 |
|
|
|
|
Current U.S.
Class: |
254/134.3FT |
Current CPC
Class: |
H02G 3/00 20130101; H02G
1/083 20130101; H02G 1/06 20130101 |
Class at
Publication: |
254/134.3FT |
International
Class: |
H02G 3/00 20060101
H02G003/00 |
Claims
1. An apparatus for pulling a cable through a conduit, comprising:
a frame; a boom pivotally connected to the frame and including at
least one roller configured to guide a rope connected to the cable
along the boom; and a plurality of ground-engaging wheels
supporting the frame, at least some of the wheels being caster
wheels that are rotatable about a vertical axis relative to the
frame to steer the apparatus thereby.
2. An apparatus as claimed in claim 1, wherein the caster wheels
include one caster wheel at each side of the frame at a first end
of the frame.
3. An apparatus as claimed in claim 2, wherein the boom is
pivotally connected to the frame at the first end of the frame.
4. An apparatus as claimed in claim 3, wherein the boom extends
from where it is pivotally connected to the frame upwardly and in a
direction toward a second end of the frame opposite from the first
end and is adapted to support a handle spaced apart from the
pivotal connection of the boom to the frame.
5. An apparatus as claimed in claim 2, wherein the wheels include
non-caster wheels that are fixed to the frame so as not to rotate
about a vertical axis relative to the frame at a second end of the
frame that is opposite from the first end of the frame.
6. An apparatus as claimed in claim 2, wherein the caster wheels
have brakes.
7. An apparatus as claimed in claim 2, wherein the apparatus
includes a lift assist mechanism to raise the boom.
8. An apparatus as claimed in claim 2, wherein the boom includes a
capstan adapted to be operated to apply tension to a rope.
9. An apparatus as claimed in claim 2, further comprising a joint
pivotally connecting a first member to a second member of the boom
and including a pin having an axis and being movable axially from a
first position to a second position and vice versa, in the first
position the pin fixing the first and second members angularly
relative to one another and in the second position permitting the
first and second members to pivot relative to one another.
10. An apparatus as claimed in claim 9, wherein in both the first
position and the second position the pin is constrained by the
joint.
11. An apparatus as claimed in claim 10, wherein the pin is biased
toward the first position.
12. An apparatus as claimed in claim 11, wherein the joint includes
an adjustment slot through which the pin moves when the pin is in
the second position.
13. An apparatus as claimed in claim 2, wherein the boom extends
from where it is pivotally connected to the frame upwardly and in a
direction toward a second end of the frame opposite from the first
end and is adapted to support a handle spaced apart from the
pivotal connection of the boom to the frame.
14. An apparatus as claimed in claim 13, wherein the handle is
along an axis of a roller at a joint of the boom.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/825,499 filed Jun. 29, 2010, which will
issue as U.S. Pat. No. 8,434,741 on May 7, 2013, and which claims
the benefit of U.S. Provisional Patent Application No. 61/221,290
filed Jun. 29, 2009, the disclosure of which is hereby incorporated
by reference in its entirety.
STATEMENT CONCERNING FEDERALLY SPONSORED RESEARCH OR
DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to powered cable pullers for
routing cables and wiring through conduits.
[0004] Cable pullers are well-known devices for pulling power
cables, data cables, or other wiring through both horizontal and
vertical building conduits; the cables are usually pulled upwardly
(referred to as an "up-pull") or downwardly (referred to as a
"down-pull"). Typical cable puller designs include a rope that
connects to and pulls cables through the conduit and a conduit
adapter that connects to the conduit to help support the device. In
some designs, the conduit adapter is reconfigurable or
interchangeable with other adapters to connect to conduits of
various sizes. Typical puller designs also include a boom connected
to the conduit adapter that guides the rope to a drive unit that
rotates to pull the rope. The boom includes multiple sections that
are connected by one or more pivotal joints. The pivotal joints
permit the boom to be accurately repositioned such that the device
is suitable for use with conduits that terminate at various
heights.
[0005] Typical cable puller designs, while eliminating the need for
contractors or other technicians to manually pull cables through
building conduits, include several drawbacks. For example, some
pullers are designed to have relatively high pulling capacities
(e.g., 6000 lbs or more) to overcome large friction forces when a
cable is pulled through a long conduit. High pulling capacity is
typically provided by using a larger drive unit. In addition, the
boom and other components are typically thick metal components to
provide durability and resistance to deflection due to the high
pulling forces. As a result, the large drive unit and boom cause
the device to be very heavy (e.g., 75 lbs. or more) and difficult
to reposition. A technician can be fatigued easily by lifting and
carrying such a puller if many consecutive pulls are performed.
[0006] A number of designs have been created in an attempt to
overcome the drawback of having to carry a cable puller between
different locations. For instance, some cable puller designs
include a base with wheels that support the drive unit and the
boom. Such designs permit even larger drive units and booms to be
used to further increase pulling capacity. The size of the base may
prevent these pullers from accessing smaller areas in which the
aforementioned designs fit easily. In addition, puller designs with
wheels are typically difficult for a technician to push because the
base is only inches off the ground.
[0007] All of the aforementioned puller designs are difficult to
accurately reposition after the puller is moved to the general
location of the conduit (i.e., difficult to accurately adjust the
boom to connect the conduit adapter to the conduit). This problem
occurs in part due to the weight of the cable puller as described
above. In addition, the pivotal joints of the boom each include a
pin that must be completely removed to reposition the boom
sections. After the boom is accurately repositioned, the pin must
be inserted into the joint while holding the puller in engagement
with the conduit. This can be particularly difficult if a single
technician must set up the power puller without assistance.
[0008] Further still, some of the aforementioned designs require a
technician to partially disassemble the boom to switch between
appropriate up-pull and down-pull configurations. For example, it
may be necessary to separate the boom sections and reverse the
orientation of several boom sections relative other sections. Such
actions can be time consuming and can fatigue a technician.
[0009] Considering the limitations of the previous powered puller
designs, a need exists for a design that is easily moved and
reconfigured at a work site. A need also exists for such a cable
puller to have a high pulling capacity.
SUMMARY OF THE INVENTION
[0010] In one aspect, the present invention provides a portable
apparatus for pulling a cable through a conduit. The apparatus
comprises a frame and a boom pivotally connected to the frame that
includes at least one roller configured to guide a rope connected
to the cable along the boom. Ground engaging wheels support the
frame, at least some of the wheels being caster wheels that are
rotatable about a vertical axis relative to the frame to steer the
apparatus.
[0011] In another aspect, the present invention provides an
apparatus for pulling a cable through a conduit. The apparatus
comprises a frame and a boom pivotally connected to the frame. The
boom includes at least one roller configured to guide a rope
connected to the cable along the boom. The boom further includes a
first member, a second member, and a joint connecting the first
member to the second member. The joint defines a first axis about
which the second member is pivotable relative to the first member
and a second axis about which the second member is rotatable
relative to the first member. The second axis is perpendicular to
the first axis.
[0012] In another aspect, the invention includes a lift pivotally
connected to the frame and the boom. The lift is operable to move
the boom relative to the frame.
[0013] The foregoing and other advantages of the invention will
appear in the detailed description which follows. In the
description, reference is made to the accompanying drawings which
illustrate a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will hereafter be described with reference to
the accompanying drawings, wherein like reference numerals denote
like elements, and:
[0015] FIG. 1 is a perspective view of a powered cable puller of
the invention performing an up-pull;
[0016] FIG. 2 is a side view of the powered cable puller of FIG. 1
performing an up-pull;
[0017] FIG. 3 is a partial side view of a boom of the powered cable
puller of FIG. 1;
[0018] FIG. 4 is a partial top view of the boom and a boom joint of
the powered cable puller of FIG. 1;
[0019] FIG. 5A is a side view of a pin of the boom joint in a fixed
position;
[0020] FIG. 5B is a side view of the pin of FIG. 5A with a handle
pulled to move the pin to a rotation position;
[0021] FIG. 5C is a side view of the pin of FIG. 5A with the handle
pulled and rotated to lock the pin in the rotation position;
[0022] FIG. 6 is a sectional view of the boom joint along line 6-6
of FIG. 4;
[0023] FIG. 7 is another partial side view of a boom of the powered
cable puller of FIG. 1;
[0024] FIG. 8 is a partial side view of a frame of the powered
cable puller of FIG. 1;
[0025] FIG. 9 is a side view of the powered cable puller of FIG. 1
performing a down-pull;
[0026] FIG. 10 is a perspective view of the powered cable puller of
FIG. 1 performing a down-pull;
[0027] FIG. 11 is a perspective view of the powered cable puller of
FIG. 1 performing a side-pull;
[0028] FIG. 12 is a perspective view of the powered cable puller of
FIG. 1 in a storage position;
[0029] FIG. 13 is a side view of the powered cable puller of FIG. 1
in the storage position;
[0030] FIG. 14 is a side view of the powered cable puller of FIG. 1
as viewed from the opposite direction as FIG. 13;
[0031] FIG. 14A is a detail view of the boom along line 14A-14A of
FIG. 14;
[0032] FIG. 14B is a detail view along line 14B-14B of FIG. 14;
[0033] FIG. 15 is a rear view of the powered cable puller of FIG. 1
in the storage position;
[0034] FIG. 16 is a bottom view of the powered cable puller of FIG.
1 in the storage position; and
[0035] FIG. 17 is a schematic illustration of a pump and an
actuator of the powered cable puller of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] The particulars shown herein are by way of example and only
for purposes of illustrative discussion of the embodiments of the
invention. The particulars shown herein are presented to provide
what is believed to be the most useful and readily understood
description of the principles and conceptual aspects of the
invention. In this regard, no attempt is made to show structural
details of the invention in more detail than is necessary for the
fundamental understanding of the invention. The description taken
with the drawings should make apparent to those skilled in the art
how the several forms of the present invention may be embodied in
practice.
[0037] Referring now to the figures and particularly FIG. 1, a
powered cable puller 10 of the present invention includes a conduit
adapter 12 for engaging a conduit 14 that may be part of an
electrical box or recessed in a wall or surface 16 of a building.
The puller 10 further includes a boom 18 that supports the conduit
adapter 12 and a drive unit 20 that rotates to pull a rope 22
connected to one or more cables (e.g., power cables, data cables,
or other wiring). The boom 18 is pivotally supported by a frame 24
and is reconfigurable to perform various types of pulls, such as
up-pulls (FIGS. 1 and 2), down-pulls (FIGS. 9 and 10) and
side-pulls (FIG. 11), and to fold to a storage position (FIGS.
12-16). These components and their interactions are described in
further detail in the following paragraphs, beginning with the
conduit adapter 12 and then proceeding to the boom 18 and the frame
24.
[0038] Referring to FIGS. 2, 3, and 10, the conduit adapter 12
includes a semi-circular adapter end 26 that engages the conduit
14. The adapter end 26 defines a passageway 28 to permit the rope
22 to pass therethrough. The adapter end 26 also connects to a
support bracket 30 that connects to the boom 18. The support
bracket 30 preferably releasably connects to the boom 18, for
example, through threaded fasteners and the like, to permit
interchangeability with adapters of other sizes.
[0039] The boom 18 includes a first end that has an adapter joint
32 that engages the conduit adapter 12. The adapter joint 32
includes a first roller 34 that is rotatably disposed between
adapter side plates 36. The first roller 34 guides the rope 22 from
the conduit adapter 12 and along the boom 18 to the drive unit 20.
The adapter side plates 36 each include a plurality of holes 38
that accommodates a first removable cotter pin assembly 40. The
first pin 40 also extends through holes in distal brackets 42 that
are pivotally connected to the side plates 36. As such, the first
pin 40 locks the side plates 36 relative to the distal brackets 42
when the pin 40 extends through one set of the holes 38. The first
pin 40 may be removed from the holes 38 and permit the adapter
joint 32 to pivot and be repositioned. It may be useful to pivot
and reposition the conduit adapter 12, for example, if the surface
16 has a slight incline. In addition to supporting the first pin
40, the distal brackets 42 also permit pivotal movement of the
first roller 34 and the adapter side plates 36 about an adapter
axis 43.
[0040] Still referring to FIGS. 2, 3, and 10, the adapter joint 32
connects to an upper boom 44. The upper boom 44 preferably includes
a telescoping boom 46 that fixedly connects to the distal brackets
42. The telescoping boom 46 also moves within a sleeve boom 48 such
that the length of the upper boom 44 may be varied. The telescoping
boom 46 and the sleeve boom 48 may be fixable to one another by a
second removable cotter pin assembly 50. In addition, the booms 46
and 48 may each be formed from tube stock material (e.g.,
2''.times.3'' tubular steel) and include separate arms 52 and 54
connected by one or more cross members 56. The end of the upper
boom 44 opposite the distal brackets 42 includes proximal brackets
58 that define a boom pivot axis 60. The upper boom 44 may pivot
relative to other sections of the boom 18 about the boom pivot axis
60. It may be useful to pivot and reposition the upper boom 44, for
example, to adjust the boom 18 to an appropriate height for a cable
pull or to fold the boom 18 to the storage position.
[0041] Referring now to FIGS. 3-6, the upper boom 44 connects to a
main boom 62. The main boom 62 includes a boom joint 64 that
connects to the proximal brackets 58 at the boom pivot axis 60. The
boom joint 64 includes a second roller 66 rotatably disposed
between joint side plates 68. The second roller 66 guides the rope
22 to the drive unit 20. The joint side plates 68 each include an
arcuate adjustment slot 70. In a preferred embodiment, each arcuate
adjustment slot 70 includes a plurality of slot indentations 72,
such as semi-circular surfaces. Each slot indentation 72 is
positioned across from a slot indentation 72 on the opposite side
of the slot 70. As such, each pair of opposite slot indentations 72
defines a slot enlargement 73, such as a circular hole that has a
diameter larger than the width of arcuate connecting holes 75
between the slot enlargements 73. The slot enlargements 73 and the
connecting holes 75 accommodate a second pin 74 as described
below.
[0042] The second pin 74 (shown separately from the cable puller 10
in FIGS. 5A-5C) includes a shaft 71 defining an axis 77. The shaft
71 is axially movable between a fixed position and a rotation
position in which the upper boom 44 is fixed and pivotable,
respectively, relative to the main boom 62. In the fixed position,
locking sections 76 of the shaft 71 are each disposed within one of
the slot enlargements 73 in the joint side plates 68 (note that in
FIG. 4 the locking sections 76 are enlarged and shown protruding
from the joint side plates 68 for clarity). The locking sections 76
have a diameter larger than the width of the arcuate connecting
holes 75. As such, the locking sections 76 are constrained in the
slot enlargements 73 and prevent the upper boom 44 from pivoting
relative to the main boom 62. As shown in FIG. 5B, the shaft 71 of
the second pin 74 is moved from the fixed position to the rotation
position by pulling a handle 80 fixedly connected to the shaft 71.
This action results in rotation sections 78 of the shaft 71 being
moved into the adjustment slot 70. The rotation sections 78 have a
diameter smaller than the width of the arcuate connecting holes 75.
As a result, in the rotation position the shaft 71 is permitted to
move through the adjustment slot 70 and the upper boom 44 is
permitted to pivot relative to the main boom 62.
[0043] In a preferred embodiment, the second pin 74 also includes a
spring 84 that biases the shaft 71 towards the fixed position. The
handle 80 also includes an annular spacer 81 having fingers 83
accommodated, in the fixed position, in finger grooves 85 of a
bracket 87 connected to one of the proximal brackets 58 by
fasteners (not shown) or the like. As shown in FIG. 5B, the fingers
83 move from the finger grooves 85 when the handle 80 is pulled and
the shaft 71 moves to the rotation position. As shown in FIG. 5C,
the handle 80 may then be turned, for example, by a quarter turn,
to move the fingers 83 out of alignment with the finger grooves 85.
The handle 80 may then be released to permit the fingers 83 to abut
the outer surface 91 of the bracket 87 and thereby hold the shaft
71 in the rotation position.
[0044] During use, a technician may pull and turn the handle 80 to
secure the shaft 71 of the second pin 74 in the rotation position
as described above. The technician may then configure the upper
boom 44 to place the adapter 12 generally in the area of the
conduit 14. Then, the technician may turn the handle 80 (for
example, by an opposite quarter turn to align the fingers 83 and
the finger grooves 85) such that the spring 84 forces the shaft 71
towards the fixed position. However, the upper boom 44 may still be
rotated relative to the main boom 62 unless the locking sections 76
of the pin 74 are aligned with a set of slot enlargements 73. That
is, the sides of the locking sections 76 will abut the side of the
joint side plates 68 surrounding the arcuate connecting holes 75
unless the locking sections 76 of the pin 74 are aligned with a set
of slot enlargements 73. The spring 84 will force the second pin 74
into a set of slot enlargements 73 once the locking sections 76 of
the pin 74 are aligned with a set of slot enlargements 73, after
which the upper boom 44 is fixed relative to the main boom 62.
[0045] From the above, it should be apparent that the second pin 74
does not need to be completely removed from the boom joint 64 to
reposition the upper boom 44. In addition, the second pin 74 does
not need to be awkwardly reinserted into the boom joint 64 as the
upper boom 44 is held in the proper position. As such, the boom
joint 64 permits the upper boom 44 to be locked and unlocked
relative to the main boom 62 by a technician only using a single
hand.
[0046] Referring now to FIGS. 4 and 6, the joint side plates 68
fixedly connect to a joint bracket 86 that supports a revolute
joint 88. The revolute joint 88 includes a joint sleeve 93 that
rotatably supports a joint shaft 95 fixedly connected to the joint
bracket 86. The joint shaft 95, and therefore the upper boom 44, is
rotatable about a revolute axis 90 that is perpendicular to the
boom pivot axis 60. Rotation about the revolute axis 90 permits the
upper boom 44 to be easily rotated to perform a down-pull (FIGS. 9
and 10) or a side-pull (FIG. 11). Of course, the rope 22 should be
routed along the boom 18 after the upper boom 44 is rotated to the
desired position so that the rope 22 does not contact or become
tangled with the boom 18.
[0047] Referring specifically to FIG. 6, the joint sleeve 93
includes upper and lower pin openings 97 that are alignable with a
first pin passageway 99 of the joint shaft 95 when performing an
up-pull (FIGS. 1 and 2) or a down-pull (FIGS. 9 and 10). A pin
assembly 89, such as a fastener that is threadably engagable with
the openings 97 or the passageway 99, may be inserted into one of
the openings 97 and the passageway 99 to lock the revolute joint 88
in a position for an up-pull or a down-pull. In some embodiments,
as shown in FIG. 6, the pin assembly 89 may include a
perpendicularly extending grip 103 for ease of rotating the pin
assembly 89. The pin assembly 89 may also be removed to rotate the
upper boom 44 and align the openings 97 with a second pin
passageway 101 of the joint shaft 95 extending perpendicularly
through the first pin passageway 99. Thereafter, the pin assembly
89 may be inserted into one of the openings 97 and the second
passageway 101 to lock the revolute joint 88 in a position to
perform a side pull (FIG. 11).
[0048] The revolute joint 88 advantageously permits the puller 10
to perform the different types of pulls described above. In
addition, the revolute joint 88 also permits the puller 10 to
operate in small spaces; for example, the puller 10 may perform a
side-pull in a narrow corridor that is only slightly wider than the
frame 24. Further still, the revolute joint 88 permits the puller
10 to switch between different types of pulls without requiring
disassembly of the boom; for example, the upper boom 44 does not
need to be separated from the main boom 62.
[0049] In addition to providing the multiple pivot axis structure
described above, the boom joint 64 also supports handles 61 that
extend along the pivot axis 60. When the boom 18 is folded to the
storage position (FIG. 12), the handles 61 are positioned such that
they may be easily grasped by a technician and the puller 10 may be
moved thereby.
[0050] Referring now to FIGS. 2, 7, and 10, the revolute joint 88
connects to an intermediate bracket 92 that is supported by an
intermediate boom 96. The intermediate boom 96 may include separate
tube stock arms 98 and 100 connected by one or more cross members
102. The intermediate boom 96 pivotally connects to a lower boom
104 that may include separate tube stock arms 106 and 108. The
intermediate and lower booms 96 and 104 may be fixable to one
another by a second removable cotter pin assembly 110. The lower
boom 104 includes stopper plates 111 that support the intermediate
boom 96 in the operating position and support brackets 112 that
support the intermediate boom 96 in the storage position. The lower
boom 104 removably supports the drive unit 20, which may be any
appropriate design known to those skilled in the art, such as
capstan that has a rotatable spool. In addition, a proximal end of
the lower boom 104 pivotally connects to the frame 24.
[0051] Referring to FIGS. 8, 10, and 11, the frame 24 includes a
base 114 that has a generally rectangular shape. The base 114 is
defined by several arms 116 that may be, for example, the same tube
stock material used to form the arms of the boom 18. The rear end
of the base 114 connects to rear wheels 124. The rear wheels 124
may be braked casters that rotate about a vertical axis to permit,
together with the handles 61, the puller 10 to be easily steered by
a technician. These components also permit the puller 10 to be
easily steered even if it is heavy and has a relatively high
pulling capacity.
[0052] One of the base arms 116 preferably removably supports
several conduit adapters 12 of various sizes that may be
interchanged with the conduit adapter 12 connected to the boom 18.
The opposite base arm 116 supports a pump 126, such as a
manually-driven hydraulic pump including a manual pump handle 127,
that is in fluid communication with an actuator 128 that pivotally
connects to the base 114 and the boom 18 to raise and lower the
boom 18.
[0053] Referring specifically to FIG. 17, a hydraulic fluid
reservoir 151 supplies hydraulic fluid through a hydraulic fluid
delivery line 153 to the pump 126 as the handle 127 is pivoted
toward the pump 126. The pump 126 supplies hydraulic fluid through
an actuator line 155 to the actuator 128 to extend the actuator rod
141 and thereby lift the boom 18. In addition, the pump 126
includes a manual valve 157, such as a screw valve commonly used
with bottle jacks and the like, positioned along a hydraulic fluid
return line 159 connected to the reservoir 151. The valve 157 may
be opened to permit the boom 18 to lower under its own weight and
thereby force hydraulic fluid to pass through the return line 159
and into the reservoir 151. The return line 159 preferably includes
a flow limiter 161 to reduce the flow rate as the hydraulic fluid
returns to the reservoir 151, thereby forcing the boom 18 to lower
slowly. That is, the flow limiter 161 has a fluid passageway having
a smaller cross-sectional area than that of the actuator line 155,
so as to slow down the rate that the boom 18 will lower under its
own weight when the valve 157 is opened. The pump 126 may also
include other appropriate components recognized by those skilled in
the art, such as check valves, pilot valves, and the like.
[0054] The actuator 128 also pivotally connects to a linkage
assembly 130 that raises and lowers the lower boom 104 as the
actuator 128 extends and retracts, respectively. As best understood
from FIG. 11, the actuator 128 extends to unfold the linkage
assembly 130 and raise the lower boom 104. Conversely, the actuator
128 retracts to fold the linkage assembly 130 and lower the lower
boom 104.
[0055] Referring to FIGS. 8 and 11, the linkage assembly 130 is
supported by a cross member 131 connected between the base arms
116. The linkage assembly 130 includes lower links 133 that are
preferably identical components. Each lower link 133 includes a
first end 135 pivotally connected to the cross member 131 and a
second end 137 pivotally connected to an actuator cross member 139.
As the name implies, the actuator cross member 139 connects to the
extendable rod 141 of the actuator 128. Upper links 143 of the
linkage assembly 130 are also preferably identical components and
each includes a first end 145 pivotally connected to the actuator
cross member 139. Each upper link 143 also includes a second end
147 (FIG. 8) pivotally connected to the one of the arms 106 or 108
of the lower boom 104.
[0056] The actuator 128 preferably only extends a limited amount
(e.g., an amount such that the lower boom 104 rotates at most 30
degrees relative to the base 114). The pump 126, actuator 128, and
the linkage assembly 130 advantageously support the boom 18 during
a pull and during setup for a pull, thereby reducing the amount of
lifting required by a technician. These components also help hold
the conduit adapter 12 in engagement with the conduit 14 during a
down-pull. Alternatively, the pump 126 and the actuator 128 could
be replaced by a manual crank lift (not shown).
[0057] A front end of the base 114 connects to one or more boom
supports 132 that support the lower boom 104 in the storage
position. The front end of the base 114 also connects to front
wheels 134 that are preferably fixed axle wheels. Each of the base
arms 116 preferably connects to a lifting handle 136. The lifting
handles 136 may be used to lift the puller 10, for example, into a
vehicle. The sides of the base 114 also preferably connect to a
drive unit bracket 138 that supports the drive unit 20 in the
storage position.
[0058] The powered puller 10 is preferably set up for a pull as
follows: starting from the storage position, the rear wheels 124
are locked using the brakes. Next, the hydraulic pump 126 is
operated, for example, using the manual pump handle 127, to pivot
and lift the lower boom 104 above the frame 24. The intermediate
boom 96 is then unfolded from the lower boom 104 so that the
stopper plates 111 support the intermediate boom 96. The
intermediate boom 96 is also locked in place by the pin assembly
110. Next, the second pin 74 is moved to the second position to
permit the upper boom 44 to pivot upwardly. The second pin 74 is
then moved to the first position to fix the upper boom 44 relative
to the intermediate boom 96. Next, the telescoping boom 46 may be
extended from the sleeve boom 48 and the upper boom 44 may be
rotated about the revolute axis 90 if a down-pull or a side-pull is
to be performed. Finally, the first pin 40 may be removed such that
the conduit adapter 12 may be repositioned to engage the conduit
14.
[0059] From the above disclosure, it should be apparent that the
powered cable puller of the invention may provide any combination
of the following advantages: high pulling capacity and ease of
movement and reconfiguration in an operating position, performance
of various types of pulls even in relatively small spaces, and ease
of transport in a storage position.
[0060] A preferred embodiment of the invention has been described
in considerable detail. Many modifications and variations to the
preferred embodiment described will be apparent to a person of
ordinary skill in the art. Therefore, the invention should not be
limited to the embodiment described, but should be defined by the
claims that follow.
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