U.S. patent application number 11/473433 was filed with the patent office on 2006-10-19 for underground cable laying apparatus.
Invention is credited to Steve Searby.
Application Number | 20060233615 11/473433 |
Document ID | / |
Family ID | 34394305 |
Filed Date | 2006-10-19 |
United States Patent
Application |
20060233615 |
Kind Code |
A1 |
Searby; Steve |
October 19, 2006 |
Underground cable laying apparatus
Abstract
Presented is an underground cable laying apparatus that leaves
virtually no visible scar in the turf under which cable, wire,
line, hose, etc. is laid. The apparatus utilizes a pair of
angularly displaced turf slicing wheels to slice and separate the
turf forming a slit into which cable may be laid. A cable guide
tube and roller properly place the cable within the slit. A pair of
turf closure wheels close the slit in close proximity to the
release point of the cable to ensure proper placement of the cable.
The slit in the turf is gently and completely closed over the
cable, leaving virtually no visible scar within the turf to upset
the aesthetic beauty of a lawn. Further, the configuration and
rolling action of the turf slicing wheels ensures that other
underground cables will not be damaged if inadvertently
encountered.
Inventors: |
Searby; Steve; (Lena,
IL) |
Correspondence
Address: |
REINHART BOERNER VAN DEUREN P.C.
483 NORTH MULFORD ROAD
SUITE 7
ROCKFORD
IL
61107
US
|
Family ID: |
34394305 |
Appl. No.: |
11/473433 |
Filed: |
June 23, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10680059 |
Oct 7, 2003 |
7090433 |
|
|
11473433 |
Jun 23, 2006 |
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Current U.S.
Class: |
405/180 |
Current CPC
Class: |
F16L 1/032 20130101;
H02G 1/06 20130101; E02F 5/101 20130101; E02F 5/08 20130101; E02F
5/12 20130101 |
Class at
Publication: |
405/180 |
International
Class: |
E02F 5/10 20060101
E02F005/10 |
Claims
1. An underground cable laying apparatus, comprising: a mounting
yoke; a pair of angularly displaced turf slicing wheels rotatably
coupled to the mounting yoke, the turf slicing wheels defining a
forward contact area therebetween; and a cable guide tube
positioned aft of the forward contact area of the turf slicing
wheels, the cable guide tube having a cable inlet and a cable
outlet.
2. The underground cable laying apparatus of claim 1, wherein, each
of the angularly displaced turf slicing wheels defines a radius and
an outer periphery thereof, and is mounted for rotation about a
respective turf slicing wheel axis directed such that, when viewed
from either side of the apparatus, the outer peripheries of the
turf slicing wheels are substantially superimposed upon one another
vertically and horizontally, with the peripheries coming together
at a point of contact in the forward contact zone and disposed
substantially horizontally forward of the axes of the turf slicing
wheels.
3. The underground cable laying apparatus of claim 2, wherein, the
point of contact is angularly positioned within a range of zero to
20 degrees down from a horizontal extension of the axes.
4. The underground cable laying apparatus of claim 2, wherein, the
point of contact is vertically positioned substantially
horizontally level with the axes, and substantially at ground level
when the apparatus is slicing the turf, such that substantially the
entire radius of the turf slicing wheels is disposed below ground
level in operation.
5. The underground cable laying apparatus of claim 4, wherein, the
pair of turf slicing wheels are angularly displaced relative to one
another along a vertical axis of the mounting yoke in such a manner
that the forward contact area is disposed substantially below the
point of contact, and outer peripheries of the turf slicing wheels
diverge below the forward contact area, in such a manner that the
slit in the turf has a defined horizontally extending bottom width
thereof, rather than being substantially V-shaped and terminating
in a vertex of the V-shape at the bottom of the slit.
6. The underground cable laying apparatus of claim 1, wherein the
pair of turf slicing wheels are angularly displaced relative to one
another along both a horizontal and a vertical axis of the mounting
yoke.
7. The underground cable laying apparatus of claim 1, further
comprising: a turf closure housing pivotally coupled relative to
the mounting yoke; and a pair of angularly positioned turf closing
wheels rotatably coupled to the turf closure housing.
8. The underground cable laying apparatus of claim 7, further
comprising a pair of closure assembly mounting arms fixably coupled
to the mounting yoke, and wherein the turf closure housing is
pivotally coupled to the closure assembly mounting arms.
9. The underground cable laying apparatus of claim 7, further
comprising, a turf follower spring coupled between the mounting
yoke and the turf closure housing.
10. The underground cable laying apparatus of claim 9, further
comprising, a spring tension nut positioned to vary a bias force
supplied by the turf follower spring.
11. The underground cable laying apparatus of claim 1, further
comprising, a feed tube support extension member coupled to the
cable guide tube in proximity to the cable outlet.
12. The underground cable laying apparatus of claim 1, further
comprising, a cable guide coupled to the cable feed tube and
displaced from the cable inlet to aid in guiding cable into the
cable inlet.
13. The underground cable laying apparatus of claim 1, wherein, the
cable guide tube is curved from the cable inlet to the cable
outlet.
14. The underground cable laying apparatus of claim 13, wherein,
the outlet of the cable guide tube is oriented to discharge the
cable substantially horizontally.
15. The underground cable laying apparatus of claim 1, wherein the
mounting yoke includes at least one mounting receptacle.
16. An apparatus for laying cable under turf without leaving a
visibly obvious scar in the turf, comprising: a mounting yoke
having at least one mounting receptacle defined therein; a pair of
turf slicing wheels rotatably mounted on the mounting yoke, the
turf slicing wheels being positioned in a diverging relationship to
one another such that a slit is opened in the turf when the pair of
turf slicing wheels is pulled therethrough; and a cable feed tube
positioned between the pair of turf slicing wheels and terminating
in a cable outlet positioned to guide the cable into the slit
opened by the pair of turf slicing wheels.
17. The apparatus of claim 16, further comprising a turf closure
assembly operably coupled to the mounting yoke and positioned
relative to the pair of turf slicing wheels to close the slit in
the turf opened thereby anterior of the cable outlet.
18. The apparatus of claim 17, wherein the turf closure assembly
comprises a pair of turf closing wheels angularly positioned
relative to one another and laterally displaced from one another a
distance greater than a lateral spacing at a trailing edge of the
pair of turf slicing wheels.
19. The apparatus of claim 16, further comprising a cable feed
guide mechanism positioned anterior and vertically downward of the
cable outlet relative to a surface of the turf to position the
cable within the slit in the turf and to protect an outer surface
of the cable from scraping.
20. A method of laying cable under a lawn, comprising the steps of:
lowering a pair of turf slicing wheels into the lawn; moving the
pair of turf slicing wheels through the lawn to open a slit
therein; guiding cable into the slit in the lawn; and closing the
slit after the cable has been positioned therein.
21. The method of claim 20, wherein the step of moving the pair of
turf slicing wheels through the lawn comprises the step of moving
the pair of turf slicing wheels through the lawn such that the pair
of turf slicing wheels rotate.
22. The method of claim 20, further comprising the step of watering
the lawn prior to the steps of lowering, moving, guiding, and
closing.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This patent application is a continuation-in-part of
co-pending U.S. patent application Ser. No. 10/680,059, filed Oct.
7, 2003.
FIELD OF THE INVENTION
[0002] This invention relates generally to apparatuses and methods
for laying underground cable or irrigation tubing.
BACKGROUND OF THE INVENTION
[0003] Aesthetics have always played an important role in home
design and landscaping. Indeed, most homeowners take pride in the
appearance of their yards and landscaping, often devoting many
hours each weekend to ensuring that their lawn and garden look
attractive and uncluttered.
[0004] Unfortunately, the necessities of day-to-day living often
result in the use and installation of unsightly equipment. For
example, the use of a garden hose and sprinkler to water the lawn
and garden, the use of a fence to contain a pet, the running of
cables and wires for lighting, cable TV, internet services, etc.
all are visibly unappealing to many homeowners. The solution of
choice for many homeowners is to run such cables, wires, pet
containment systems, sprinkler systems, etc., underground so as to
be hidden from view while still allowing the homeowner to reap the
benefits provided thereby.
[0005] To run each of these varied systems underground, in the
past, trenchers have been used to dig a small trench in the yard
into which is laid the cable, wire, pipe, etc., for the particular
system being installed. The soil removed from the trench is then
put back in over the wire, cable, pipe, etc. In this way, each of
these systems, wires, cable, etc., are hidden from view.
[0006] Unfortunately, this solution to the aesthetic problem has
resulted in an underground maze of wires, cable, pipes, etc., for
which no coordinated mapping is typically provided. Further,
utility marking services such as JULIE do not provide marking of
such consumer-installed underground cables, wires, pipes, etc.,
instead only marking the main utilities of gas, electric, water,
etc. As a result, the attempted installation of subsequent
underground systems using a trencher often results in damage or
breakage of the underground lines, cables, wires, pipes, etc., of
previously installed underground systems. This not only results in
frustration of the homeowner as the affected system may no longer
be used until it is repaired, but also additional expense for the
installers of the subsequent underground systems who have caused
the damage and now must bear the expense of repair. Additionally,
the type of damage resulting from the use of current methods for
underground cable laying often results in multiple breaks in the
underground system. That is, oftentimes the underground line,
cable, wire, pipe, etc., is snagged by these trenching apparatus
and pulled along until a failure occurs in the affected system.
Such failures may be at locations other than the point at which the
system was snagged by the trencher, often requiring a large portion
of the damaged underground system to be dug up to effectuate the
repair at the locations of the break.
[0007] A further disadvantage with current methods for laying
underground cable, wire, flexible tubing, etc., is that the current
methods leave a visible scar in the yard. This scar typically
requires the planting of additional grass or other ground cover
seed, which further increases the expense, detracts from the
aesthetics which it was meant to protect, and requires additional
lawn care to properly water the newly planted seed to ensure
germination and full growth to fully hide the trenched scar.
[0008] The above-mentioned problems, and desires, are not limited
to residential installations, but are also encountered in
institutional and commercial settings. For example, a great deal of
care is often lavished on establishing and maintaining healthy turf
on athletic fields, used for playing football, baseball, soccer, or
other outdoor sports. Large grassy areas, forming part of the
landscaping around commercial buildings, in public or private
parks, and on golf courses, are also examples of places in which it
is often necessary, or desirable, to provide complex underground
irrigation installations, or to run cabling for electric power,
communication, lighting systems, or heating systems under the
surface of the turf.
[0009] Where it becomes necessary, or desirable, to run additional
cables or tubing through an area of established turf, it is
desirable that such additional cables or tubing be installed in a
manner which does not leave a visible scar in the existing turf, or
damage underground cable or tubing which is already in place under
the turf.
[0010] Previously available equipment and methods have not proved
to be entirely satisfactory in alleviating the above-mentioned
problems, and in meeting the above described desires. For example,
in one piece of equipment currently being marketed for installation
of subsurface dripperlines in turf grass, a multi-blade lawn plow
includes a vertically mounted coulter wheel, for slicing through
the turf of a football field, or the like, followed by a ripper
blade extending below the coulter wheel, and having a passage
therein for feeding dripperless irrigation tubing into the ground
behind the ripper blade. The lawn plow further includes a pair of
tamping feet mounted adjacent the ripper blade for compacting the
soil after the dripperline has been buried. The entire multi-blade
plow apparatus is mounted on a frame, which is in turn attached to
a vibrating mounting arrangement of a trenching-type machine. Where
the subsurface installation includes existing underground cabling
and/or tubing, the ripper blades of the multi-blade lawn plow will,
in all probability, catch and cut, or otherwise damage, the
existing underground installation. The narrow, relatively sharp
edges of the vertically oriented coulter wheels may also cut or
damage the existing underground installation. It is, therefore,
unlikely that such a multi-blade lawn plow could be utilized for
installing cable or dripperline irrigation tubing in a turf grass
installation having existing underground heating cables, for
example.
[0011] It is also not likely that such a multi-blade lawn plow
could be utilized for laying dripperline irrigation tubing over the
top of an existing irrigation tubing system, supplying traditional
sprinkler heads, for example, without prior removal of the existing
sprinkler tubing. Attempts to utilize such a multi-blade lawn plow
for laying the dripperline irrigation tubing under the surface of
the ground on top of the existing tubing feeding traditional
sprinkler heads would likely result in the ripper blades catching
on the previously installed irrigation tubing, and thereby causing
significant damage to the turf grass surface as the existing tubing
is pulled along by the ripper blades.
[0012] In addition to the above-mentioned problems with utilizing
previously available trenching equipment and lawn plows, such as
leaving a visible scar in the turf, and/or cutting, catching, or
otherwise damaging previously installed underground facilities,
there are further difficulties which must be overcome, in placing
underground cable, wire, line, tubing, etc. under a turf surface.
For example, cable, of the type utilized in cable television
installations, is typically supplied on reels having a relatively
small diameter. As a result of the relatively small reel diameter,
the cable tends to develop a shape memory which will cause it to
attempt to re-coil itself, and, in the process, spring upward out
of the ground, if it is not secured by a significant amount of soil
pressure. In addition, care must be taken to ensure that the cable
is not kinked, damaged by abrasion, cut, or overly strained while
being guided into the soil under the turf. In this regard, it is
necessary that the bend radii imposed by application equipment be
relatively large. As a further complication, the outer surfaces of
the cable, and/or tubing, etc., being laid is of a nature which can
create substantial frictional force against various structures of
an apparatus being utilized for installing the cable and/or tubing.
If the frictional force of the laying mechanism, together with any
resistance to movement through the apparatus by changing the
direction of the cable, is not kept relatively low, the laid cable
or tubing will be dragged along with the placement machine, rather
than remaining where it is laid down under the turf.
[0013] Maintaining the health and appearance of the turf during and
subsequent to installation of the cable or tubing also requires
considerable care. It is necessary, for example, to close any
opening made for laying the cable or tubing quickly enough, and
with properly applied closure force so that exposure of the roots
to drying and sunlight, will be minimized, and in such a manner
that effective contact of the roots with the surrounding soil will
be reestablished following closure of the opening in the turf.
[0014] Through consideration of the above described problems and
desires, the inventor of the present invention came to recognize
that an improved apparatus, differing substantially from those
previously known, would be required. In this regard, the inventor
determined that an apparatus and method utilizing equipment for
cutting a slice through the turf by action of a rolling element
would be preferable to previously known approaches using ripper
blades or other types of traditional trenching equipment.
[0015] The inventor further recognized that the nature of the turf
itself, when subjected to slicing in an appropriate manner, could
be used to significant advantage in developing a new and improved
apparatus and method for laying underground cable, wire, line
tubing, etc. For example, unlike loose or bare soil, turf tends to
spring back, of its own accord, to close any slits cut therein.
Turf also tends to hold loosened soil in place, within the roots,
rather than allowing the soil to be moved upward onto the surface
of the ground.
[0016] The inventor also observed that even a relatively
shallow-rooted layer of turf, such as freshly laid sod, provided
substantial resistance to having a cable pop back out of the
ground, once the turf and soil was compacted back into place over
the laid cable or tubing. This was observed to be particularly the
case in well-watered turf.
[0017] Having concluded that traditional trenching equipment and
methods were unlikely to provide an improved apparatus and method,
solving the problems and meeting the desires laid out above, the
inventor considered a variety of other solutions, including the use
of various structural aspects of equipment utilized for planting
seeds through both conventional and reduced or zero tillage
methods. Such seed planting equipment has traditionally included
the use of one or more rolling coulters, in conjunction with some
form of seed feeding tube or structure, and a closure device, for
creating shallow V-shaped furrows into which the seed is
deposited.
[0018] Such traditional seed-planting-type equipment is not
suitable for use, however, or readily adapted for use, in laying
underground cables or tubing, under turf.
[0019] As illustrated in FIGS. 7a and 7b, the rotating coulter A,
or coulters, of seed planting equipment is typically designed for
rather shallow penetration into the soil, to provide a V-shaped
furrow, which extends only a limited distance D below the surface
of the ground G, with the depths of such furrows typically being in
the range of 1-4''. The actual depth D will be determined by the
particular type of seed being sown, but in general, the seed must
be kept within a limited distance of the top of the ground G, in
order for the plant emerging from the seed to reach and extend
above the surface G of the ground, and begin producing energy
through photosynthesis, prior to the nutritional reserves in the
seed itself being exhausted. Stated another way, it is necessary to
place seed relatively close to the ground surface B, in order for
the seeds to germinate properly and survive. The shallow depth D of
the V-shaped furrow produced by seed planting equipment is
therefore considerably less than the depth, for example 5-10'', at
which it is desired to lay underground cable or irrigation
tubing.
[0020] In order to create the V-shaped furrow desired for seed
planting, a typical seed planting apparatus often utilizes multiple
coulters A or disks having a point of contact C with one another
that is located at a considerable distance below a center B of the
coulter A or disk, with the coulter A or disk angling outward
vertically above and horizontally aft of the point of contact C.
The point of contact C is often selected to correspond with the
ground level G, when the seed planting mechanism is penetrating the
soil and forming a V-shaped furrow of the desired depth D.
[0021] As illustrated in FIG. 7a, this results in the depth D of
the V-shaped furrow being substantially less then the radius R of
the coulter or disk A. For example, in an apparatus disclosed in
U.S. Pat. No. 5,724,902, two disk blades are positioned to form a
V-shaped furrow opener with a contact point between the disks 20
and 22 being located substantially at an angle of 35.degree. from
the vertical axis (i.e. an angle of 55.degree. down from the
horizontal axis passing through the center B of the disk A). One of
the disks is smaller, and is mounted vertically with no
inclination. The larger of the two disks is inclined 6.degree.
along an axis extending through the contact point and the larger
disks center, to thus form a compound angle in both the vertical
and horizontal planes. By virtue of this arrangement, the tangency
or contact point of the two disks is located approximately 1.25''
above the lower edges of the disks, and is thus located at the soil
surface when the seeding tool is operated at a planting depth of
1.25''.
[0022] In similar fashion, U.S. Pat. No. 4,493,274, discloses a
pair of forming disks having a 14'' diameter and staggered
longitudinally by 1'', fore and aft with respect to one another,
and the axes inclined so that the included angle is 9.5.degree. and
the disks substantially contact each other at a point forward of
their axes at about 38.degree. downwardly from the horizontal. By
virtue of this arrangement, the 14'' diameter disks create a furrow
having a 2.69'' depth, when the point of contact is located at the
surface of the soil.
[0023] Because of the point of contact C is located so low on the
disks A of prior seed planting equipment, and as a result of the
disks A being angled with respect to one another and diverging
upward of the point of contact, if such seed planting equipment
were forced deeper into the ground, the disks A would cease to
function properly, with the individual disks A each cutting a
separate slit into the soil at the surface G of the ground, while
leaving undisturbed soil in the space between the upwardly
diverging edges of the disks A.
[0024] An additional problem preventing the use of prior
seed-planting equipment for laying of cable or tubing stems from
the fact that such seed-planting equipment is typically designed
for use only in relatively loose, non-turf applications. This is
true, even for so-called reduced tillage planting equipment. In
general, the rotating coulters or disks of a seed-planting
apparatus are utilized to cut through the soil, and by virtue of
the compound angling of the disks, to remove the soil from the
furrow and deposit it onto the ground alongside the furrow, so that
the seeds may be placed into the vertex at the bottom of the
V-shaped furrow. The seed-planting apparatus typically includes a
closure mechanism which moves the soil removed from the furrow back
into the furrow, to close the furrow, and firm the soil over the
seeds to provide good soil contact with the seed in the furrow and
to crush the sides of the furrow to provide a loose layer of soil
over the seeds, in the manner described, for example, in U.S. Pat.
No. 5,092,255. For proper germination of the seed, soil contact is
required, but it is also desirable that the soil not be overly
compacted to the point where the plant emerging from the seed will
be prevented from reaching the surface of the ground and emerging
from the furrow. It will be noted, by those having skill in the
art, that the seeds are also individual elements, which are
individually placed into the furrow, in stark contrast to a
continuous length of cable or tubing which may have a shape memory
tending to cause it to coil spring back out of the ground, or
otherwise move during the process of being laid into the soil. The
loose nature of soil placed back into the furrow by a closure and
firming apparatus of a seed planter is thus not designed, and is
totally inadequate for compressing the soil over a cable or
irrigation tube to the degree required for subsurface cable or
tubing installation, particularly when laying cable with a shape
memory tending to cause the cable to re-coil and pop out of loosely
packed or firmed soil.
[0025] As previously stated, prior seed-planting equipment,
including so-called zero-tillage or reduced-tillage planters are
not designed for use in turf applications. Trash remaining on the
surface of the soil, or clumps of turf will typically result in
substantial interference with the operation of typical planting
equipment. In order to deal with this problem, it is common
practice for prior seed-planting equipment to include various types
of trash cutting blades ahead of coulters used for making a furrow
in the soil. Such trash cutting devices have included, for example,
a wavy-edged coulter wheel for slicing up and disbursing any trash
or clumps of turf in the path of the furrow-forming coulter wheel.
Such trash cutting and disbursing devices leave unsightly scared
areas in turf, and would be totally antethical to the purposes of
the present invention. It is noted that in some prior types of
planters, used for placing seed into grassy surfaces of a pasture,
or the like, single vertical coulters are utilized for cutting a
very shallow (less than 1'' deep, for example) furrow into the
ground with the seed being deposited therein, as part of an
apparatus commonly known as a drill, rather than a planter.
[0026] The seed delivery tubes, of the type used in seed planting
equipment, are also typically designed to extend substantially
vertically, in order to maximize delivery rate of the seed into the
furrow. As disclosed in U.S. Pat. No. 6,347,594 B1, curved delivery
tubes tend to cause reduced delivery rate, and are thus typically
not utilized in seed planting equipment. Vertical, non-curved,
delivery tubes, of the type typically used in seed planting
equipment, would be highly undesirable, and essentially unworkable,
for feeding cable or tubing. Such a vertically oriented, non-curved
configuration, would not lend itself at all to smoothly feeding
cable or tubing into the ground in a horizontal direction, behind a
coulter wheel or wheels, in a manner which did not create excessive
drag within the delivery tube, or other adverse affects such as
straining, scraping, or kinking of the cable or tube at the point
where it must make a transition from the end of the essentially
vertically oriented delivery tube into the horizontal resting
position it must assume at the bottom of the furrow created by the
coulter wheels.
[0027] Prior seed-planting apparatuses also do not include any
structure or device capable of holding a cable or tube stationary
within the bottom of a trench or furrow, while the trench or furrow
is closed and the soil compacted sufficiently around the cable or
tube to prevent it from springing out of the trench or being
dragged along with the cable-laying machine. Although some prior
seed-planting machines include provisions for precluding having the
seed bounce out of the furrow, prior to being covered, these
devices would not be useful for holding a cable or tube in place,
in accordance with the requirements of the present invention. For
example, in U.S. Pat. No. 4,253,412, to Hogenson, a series of
plates are joined together by pairs of links and attached behind
the discharge end of a seed delivering boot. The plates of Hogenson
are not capable of exerting any appreciable downward force for
holding a cable or tube in place, in the manner required by a cable
laying apparatus. U.S. Pat. No. 5,092,255, to Long et al., and U.S.
Pat. No. 5,918,557, to Schaffert, disclose seed boot extensions for
reducing seed bounce and to help direct bouncing seeds into the
vertex in the bottom portion of a V-shaped furrow. The boot
extensions of Long and Schaffert are formed from a flexible
material, in order to allow the boot extension to ride up over any
chunks of soil within the furrow. The extensions of Long and
Schaffert would not apply sufficient force for holding a cable or
tube, in accordance with the requirements of the invention. In
addition, the extension of Schaffert is supported at a distance
above the furrow, for deflecting seed back into the furrow, but
does not contact the furrow or seed continuously.
[0028] U.S. Pat. No. 5,673,638, to Keeton, discloses a resilient
seed firming attachment for a planting machine having a free end,
which is cylindrically shaped, or otherwise configured into a shape
such as an inverted V shape substantially conforming to the furrow
shape, for positioning seed kernels into the furrow apex. Given the
downwardly convex shape of the seed forming attachment of Keeton,
it will be apparent, to those having skill in the art, that the
seed firming attachment of Keeton would not be usable for holding a
cable or tube in place, in accordance with the requirements of the
invention. Specifically, the downwardly convex surface of the seed
firming attachment of Keeton would not remain positioned on top of
the upwardly convex surface of the cable or tubing, but would tend
to slide off of the upwardly convex surface of the tubing, or would
allow the cable or tubing to slide outward and upward around the
firming attachment of Keeton. As a result, the cable or tube would
not be held in place, and would likely be pulled upward out of the
ground and potentially be wrapped around the firming attachment of
Keeton.
[0029] As a final point of inadequacy of prior seed-planting
apparatuses to be utilized for, or to be readily adapted for,
laying a cable or tube, it will be noted that the furrow closure
and firming arrangements of seed-planting apparatuses have
typically been positioned at a relatively long distance behind the
coulters utilized for making the furrow. This elongated spacing
would make it more difficult to achieve the various requirements of
the present invention, such as quickly closing the turf, after
insertion of the cable or tubing, and compacting the turf and soil
over the laid cable or tubing to a degree sufficient to hold it in
place within the soil and preclude having the cable or tube being
drawn through the soil with the apparatus used for installing the
cable or tube under the turf.
[0030] There exists, therefore, a need in the art for a new and
improved underground cable, wire, line, tubing, etc., laying
apparatus and method that substantially reduces or eliminates the
risk of breaking other underground systems, and which does not
leave a visible scar in the yard that requires additional care and
expense to correct.
BRIEF SUMMARY OF THE INVENTION
[0031] The term "cable", as used herein, with regard to describing
the present invention, is intended to be construed broadly to
include not only cable, but also line, wire, hose, fiber optic
cable, tubing, etc., or the like, that one may desire to vary under
the surface of the ground, and in particular, under the surface of
soil having turf growing thereon.
[0032] The present invention provides a new and improved
underground cable and the like laying apparatus. More particularly,
the present invention provides a new and improved underground cable
laying apparatus that is capable of crossing without damaging other
underground cables and the like. Further, the present invention
provides a new and improved underground cable laying apparatus that
does not leave a visibly obvious scar in the lawn under which the
cable has been laid.
[0033] In one form of the invention, an underground cable laying
apparatus includes a mounting yoke, a pair of angularly displaced
turf slicing wheels, and a cable guide tube. The pair of angularly
displaced turf slicing wheels are rotatably coupled to the mounting
yoke, in such a manner that the turf slicing wheels define a
forward contact area therebetween. The cable guide tube is
positioned aft of the forward contact area of the turf slicing
wheels, with the cable guide tube further having a cable inlet and
a cable outlet.
[0034] In an underground cable laying apparatus, according to the
invention, each of the angularly displaced turf slicing wheels may
define a radius and an outer periphery thereof, and be mounted for
rotation about a respective turf slicing wheel axis directed such
that, when viewed from either side of the apparatus, the outer
peripheries of the turf slicing wheels are substantially
super-imposed upon one another vertically and horizontally, with
the peripheries coming together at a point of contact in the
forward contact zone and disposed substantially horizontally
forward of the axes of the turf slicing wheels. The point of
contact may be angularly positioned within a range of zero to
twenty degrees down from a horizontal extension of the axes of the
turf slicing wheels. In some forms of the invention, the point of
contact may be vertically positioned substantially horizontally
level with the axes, and substantially at ground level when the
apparatus is slicing the turf, such that substantially the entire
radius of the turf slicing wheels is disposed below ground level in
operation. The pair of turf slicing wheels may be angularly
displaced relative to one another along a vertical axis of the
mounting yoke, in such a manner that the forward contact area is
disposed substantially below the point of contact, and the outer
peripheries of the turf slicing wheels diverge below the forward
contact area, in such a manner that the slit in the turf has a
defined horizontally extending bottom width thereof, rather than
being substantially V-shaped and terminating in a vertex of the
V-shape at the bottom of the slit.
[0035] In accordance with one embodiment of the present invention,
the underground cable laying apparatus includes a pair of angularly
displaced turf slicing wheels that slice and separate the turf
under which the underground cable is to be laid. A cable feed tube
is positioned between the turf slicing wheels to guide the
underground cable between the turf slicing wheels. A cable feed
guide wheel is positioned rearward of the opening of the cable feed
tube to aid in the positioning and proper laying of the underground
cable in a smooth fashion. In a preferred embodiment, the leading
edge of the cable feed tube includes a feed tube support extension
member to provide additional rigidity and stabilization of the
cable feed tube placement while laying the underground cable. A
cable guide wheel cleaning mechanism can be applied to prevent the
build up of soil on the guide wheel. A cable guide may also be
employed at an insertion end of the cable feed tube.
[0036] In a preferred embodiment of the present invention, the
underground cable laying apparatus also includes turf closing
wheels operative to close the slit in the turf into which the cable
has been laid. These turf closing wheels are carried by a turf
closure housing that is pivotably coupled to the mounting yoke of
the cable laying apparatus. Preferably, the turf closing wheels are
spring loaded by a turf follower spring within the turf closure
housing. This turf follower spring is preferably adjustable to vary
the spring load tension on the closing wheels based upon the type
of lawn under which the cable is to be laid. Positioning detents or
blocks limit the downward travel of the turf closure housing under
action of the turf follower spring.
[0037] In a preferred method of laying underground cable, and the
like, in accordance with the teachings of the present invention, a
thin slice in the turf is opened by the turf slicing wheels.
Preferably, the soil is moist, either from natural sources or from
a step of watering. Cable or the like is then positioned within the
open slice in the turf. Preferably, this step is accomplished by
guiding the cable to be laid into the slice in the turf. This step
of guiding may be accomplished in a preferred embodiment through
the use of a cable feed tube having at an aft end thereof a cable
guide, which may take the form of a wheel, roller, guide bar, etc.,
configured for maintaining the cable in the proper position within
the slice in the turf.
[0038] A cable guide, according to the invention, may take a
variety of forms having a downwardly facing, non-convex surface
thereof adapted for contacting the cable. Such a non-convex contact
surface may be flat, concave, and may include a groove therein for
partial receipt within the groove of the cable. Alternatively, or
in addition, the cable guide may be formed of a flexible material
having the ability to conform to the upwardly convex upper surface
of the cable. In some forms of the invention, the cable guide may
take the form of a flexible segment of tubing, having a bore
therein for passage therethrough of the cable, with a lower end of
the cable guide being directed, or flexibly movable by virtue of
contact with the bottom of the slice in the turf to expel the cable
in a substantially horizontal direction into the bottom of the
slice in the turf.
[0039] Preferably, the method of laying underground cable in
accordance with the present invention also includes the step of
closing the slice in the turf once the cable has been laid therein.
This step may be performed by providing a closing force in a
direction to close the slit. Preferably, this closing force is
applied to either side of the slit to preclude damage to the turf
under which the cable has been laid.
[0040] Through the method of the present invention, damage to other
underground systems, such as invisible fencing, other cables or
wires, or sprinkler systems is precluded or the likelihood of such
is significantly reduced. This is so because the rolling action of
the turf slicing wheels does not snag or otherwise cut the other
underground wires as occurs within the prior art methods of laying
cable. As such, a significant advantage is realized through the use
of the present invention for laying underground cable and the like.
Similarly, by opening a thin slice in the turf which is then closed
by applying a force to either side of the slice, the unsightly
scarring of the turf that commonly results with prior art methods
is also precluded.
[0041] Other aspects, objectives and advantages of the invention
will become more apparent from the following detailed description
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The accompanying drawings incorporated in and forming a part
of the specification illustrate several aspects of the present
invention and, together with the description, serve to explain the
principles of the invention. In the drawings:
[0043] FIG. 1 is a side view illustration of an embodiment of an
underground cable laying apparatus constructed in accordance with
the teachings of the present invention;
[0044] FIG. 2 is a cross-sectional illustration of the cable laying
apparatus of FIG. 1;
[0045] FIG. 3 is a frontal isometric view of the cable laying
apparatus of FIG. 1;
[0046] FIG. 4 is a rear isometric illustration of the cable laying
apparatus of FIG. 1;
[0047] FIG. 5 is a cross-sectional illustration of the cable laying
apparatus of FIG. 1 shown in operation laying an underground
cable;
[0048] FIG. 6 is a partial isometric illustration of a cable feed
guide wheel assembly of the cable laying apparatus of FIG. 1;
[0049] FIGS. 7a and 7b are schematic illustrations of a typical
prior art seed planting mechanism, having one or more coulters
arranged for cutting a V-shaped furrow in the earth, for deposition
of seeds therein, with the illustrations further showing that the
depth of such a V-shaped furrow below ground level is considerably
less than a radius of the coulter;
[0050] FIGS. 8a-8c illustrate the manner in which the invention is
utilized for cutting a non-V-shaped slit into turf-covered soil,
with a pair of angled coulters, in accordance with the invention,
in such a manner that the depth of the non-V-shaped slit is
significantly larger than the depth of the V-shaped furrow formed
by prior art devices and methods, with the depth of the slit,
according to the invention, being substantially equal to the radius
of the angled coulters;
[0051] FIGS. 9-11 illustrate several alternate embodiments of a
cable feed guide wheel, according to the invention, as applied in
the exemplary embodiment of the cable laying apparatus shown in
FIGS. 1-6;
[0052] FIGS. 12 and 13 illustrate an alternate embodiment of a
cable feed guide, according to the invention, having a downwardly
opening substantially convex surface thereof for contacting an
upper convex surface of a cable or tube being installed into
turf-bearing soil;
[0053] FIG. 14 illustrates an alternate embodiment of the exemplary
embodiment of the cable laying apparatus of FIGS. 1-6, which
includes a cable feed tube having a flexible outlet;
[0054] FIG. 15 illustrates an alternate embodiment, according to
the invention, of the apparatus shown in FIG. 14, with the
apparatus of FIG. 15 including a flexible cable feed tube liner and
extension; and
[0055] FIG. 16 illustrates an alternate embodiment, of the
exemplary embodiment of the cable laying apparatus shown in FIGS.
1-6, with the alternate embodiment of FIG. 16 illustrating a pair
of turf closing wheels having a flat, angled, contact surface
thereof, as compared to the rounded contacting surfaces of the turf
closing wheels shown in FIGS. 1-6.
[0056] While the invention will be described in connection with
certain preferred embodiments, there is no intent to limit it to
those embodiments. On the contrary, the intent is to cover all
alternatives, modifications and equivalents as included within the
spirit and scope of the invention as defined by the appended
claims.
DETAILED DESCRIPTION OF THE INVENTION
[0057] Turning now to the drawings, there is illustrated in FIG. 1
an exemplary embodiment of an underground cable laying apparatus 10
constructed in accordance with the teachings of the present
invention. In the interest of brevity, the term cable will be used
throughout this description to include cable, line, wire, hose,
fiber optic cable, tubing, etc., that one may desire to bury under
the surface of the ground.
[0058] As may be seen from this FIG. 1, the underground cable
laying apparatus 10 includes a mounting yoke 12 on which is mounted
a pair of turf slicing wheels 14, 16 (see FIG. 2). The mounting
yoke 12 includes mounting receptacles, for example receptacles 18,
20 that are positioned and configured to allow the apparatus 10 to
be mounted to a truck or other vehicle that will be used in the
cable laying process. As such, the particular configuration and
placement of the mounting receptacles may vary in particular
embodiments based upon the type of vehicle used in the cable laying
process. Indeed, the position and configuration of the mounting
receptacles may accommodate the usage of an intermediate mounting
or other equipment, for example a shaker unit, that may be directly
mounted to the vehicle.
[0059] In addition to the turf slicing wheels 14, 16, a turf
closing mechanism, for example turf closing wheels 22, 24 carried
on a turf closure housing 26, is pivotably mounted to the yoke 12
by the closure assembly mounting arms 28, 30. The turf closure
housing 26 may include positioning detents 32, 34, blocks,
shoulders, or other movement limiting structure to prevent the turf
closure wheels 22, 24 and their associated housing 26 from pivoting
downward beyond a desired location. However, as will be discussed
more fully below, the upward pivoting of the housing 26 is
preferably unimpeded within a range to allow the turf closing
wheels 22, 24 to follow the contours of the soil into which the
cable has been laid.
[0060] The underground cable laying apparatus also includes a cable
feed tube 36 used to guide the cable to be laid through the
apparatus 10. To facilitate this operation, the cable feed tube 36
includes a cable inlet 38 at a forward location of the apparatus 10
that receives the cable from the spool or other holding device. If
desired, the cable feed tube 36 may also include a cable guide 40
positioned above inlet 38. This cable guide 40 may have a diameter
larger than the inlet 38 to allow for some play in the cable before
it enters inlet 38. The cable feed tube 36 leads down between the
turf slicing wheels 14 to a position rearward of the leading edges
thereof. At this position the cable feed tube outlet 42 dispenses
the cable to be laid in the slice in the turf which has been
created by the turf slicing wheels 14, 16. At this outlet 42 a feed
tube support extension member 44 may be provided to add additional
stability and support for the end of the cable feed tube 36.
[0061] FIG. 2 provides a cross-sectional illustration of the
underground cable laying apparatus 10 illustrated in FIG. 1. As may
be seen from this cross-sectional illustration, the positioning of
the cable feed tube 36 preferably provides a curved path through
which the cable may be directed through the apparatus. In this way,
the possibility of snagging or chafing the exterior of the cable to
be laid is greatly reduced over prior systems that terminated in an
outlet perpendicular to the trench into which the cable was to be
laid. To further aid in the smooth and proper positioning of the
cable within the slice in the turf created by the turf slicing
wheels 14, 16, the apparatus 10 of the present invention may also
include a cable feed guide, such as wheel 46. This cable feed guide
wheel 46 is positioned in proximity to the outlet 42 to further
place the cable in the proper position in the slice in the turf
without scraping or otherwise damaging the exterior surface of the
cable. Indeed, in embodiments that utilize this cable feed guide
the cable feed tube may be straight with an outlet perpendicular to
the slit as the cable feed guide will ensure a smooth directional
change in the cable without damage thereto. To prevent the buildup
of soil within the groove 48 of the cable feed guide wheel 46, a
groove cleaning rod 50 may be provided. This groove cleaning rod 50
is positioned within the groove 48 of the cable feed guide wheel 46
in such a manner so as to prevent or reduce the amount of buildup
of soil within the groove so that the cable being dispensed may be
gently guided within the groove 48 to its proper position within
the slit in the turf.
[0062] As may also be seen from this cross-sectional illustration
of FIG. 2, the turf closure housing 26 is spring-biased to its
downward position by a turf follower spring 52. Preferably, this
turf follower spring 52 is coupled between the mounting yoke 12 via
a spring mount 56 and the rearward wall 54 of the turf closure
housing 26, rearward of the pivot point 58. The amount of force
that the turf closure wheels 22, 24 apply to the turf may be
adjusted by varying the spring tension. In the embodiment
illustrated in FIG. 2, this spring tension variation may be
accomplished by adjusting spring tension nut 60. The adjustment of
this spring tension is facilitated by the positioning detents 32,
34 as they prevent further downward pivoting of the turf closure
housing 26 through their engagement with the closure assembly
mounting arms 28, 30.
[0063] As may be seen from the frontal isometric illustration of
FIG. 3, the turf slicing wheels 14, 16 are angularly positioned
relative to one another. Preferably, they are angularly positioned
relative to both the horizontal and vertical axis of the mounting
yoke 12. That is, the turf slicing wheels 14, 16 are positioned
such that they contact each other at a contact point 61 along an
area 62, and are elsewhere displaced from one another. This
displacement between the turf slicing wheels 14, 16 preferably
increases both along a horizontal and vertical axis such that a
small slice is initiated in the turf by the forward contact area
62, and is widened along both the horizontal and vertical axes as
the apparatus 10 is moved through the turf. In this way, the turf
defining the slit is displaced both outwardly and upwardly to
accept the cable to be laid therein. With such a displacement of
the turf defining the slit, the turf closure wheels 22, which
provide an angular closing force on either side thereof, may then
fully close the slit without damage to the turf. Indeed, in most
situations the closure of the slit is complete without leaving a
residual scar in the turf whatsoever. As may be seen from this
frontal view of FIG. 3, the angular displacement of the turf
closure wheels 22, 24 is preferably greater than the angular
displacement along the same axis of the turf slicing wheels 14,
16.
[0064] As shown in FIGS. 3 and 8a, in the exemplary embodiment of
the underground cable laying apparatus 10, each of the angularly
displaced turf slicing wheels 14, 16 defines a radius R and an
outer periphery thereof, and is mounted for rotation about a
respective turf slicing wheel axis 17, 19 directed such that, when
viewed from either side of the cable laying apparatus 10, (as
depicted in FIG. 1, for example) the outer peripheries of the turf
slicing wheels 14, 16 are substantially super-imposed upon one
another vertically and horizontally, with the peripheries coming
together at the point of contact 61 in the forward contact zone 62
and disposed substantially horizontally forward of the axes 17, 19
of the turf slicing wheels 14, 16.
[0065] As illustrated in FIG. 8a, by virtue of the above described
attachment of the turf slicing wheels 14, 16, in the exemplary
embodiment of the cable laying apparatus 10, the point of contact
61 is angularly positioned within a range of zero to twenty degrees
down from a horizontal extension of the axes 17, 19. Specifically,
as shown in FIGS. 3 and 8a, the turf slicing wheels 14, 16, of the
exemplary embodiment of the apparatus 10, are operatively attached
to the mounting yoke 12, by a pair of bearings located within
bearing hubs 13, 15 attached to the turf slicing wheels 14, 16. In
the exemplary embodiment, the contact point 61 is horizontally
disposed slightly below the outer periphery of the hubs 13, 15,
which results in the point of contact 61 being vertically
positioned substantially horizontally level with the axes 17, 19,
and being positioned substantially at ground level G when the
apparatus is slicing the turf, such that substantially the entire
radius R of the turf slicing wheels 14, 16 is disposed below the
ground level G, during operation of the cable laying apparatus 10,
as illustrated in FIG. 8a.
[0066] In FIG. 8a, the turf slicing wheels 14, 16 are illustrated
with a scale diameter of 14'', and a diameter of the hubs (13, 15)
of 3''. When the turf slicing wheels 14, 16 are lowered into the
ground to a point where the hubs 13, 15 are positioned just above
the surface G of the ground, an embodiment of the invention having
14'' diameter turf slicing wheels (14, 16) and 3'' diameter hubs
13, 15, will extend into the ground to a depth D substantially
equal to the radius R of the wheels 14, 16 minus the radius r of
the hubs 13, 15, such that the resultant depth D of the slice in
the turf will have a depth of approximately 51/2'' below the
surface of the ground G. When operated in this manner, the point of
contact 61 of a 14'' diameter turf slicing wheel, with a 3''
diameter hub, will be located at an angle 21 of approximately
13.degree. downward from a horizontal extension of the axes 17, 19,
when the contact point 61 is positioned at the ground level G.
[0067] For purposes of comparison, the diameter of the coulter A in
the prior art seed-planting apparatus, shown in FIG. 7a, and the
diameter of the angularly displaced turf slicing wheels 14, 16, of
the exemplary embodiment of the invention shown in FIG. 8a are
illustrated to the same scale. By comparison of FIG. 7a and 8a, it
will be readily understood that the positioning of the contact
point 61 of the present invention is substantially different than
the position of the contact point C in seed-planting apparatuses.
In the present invention, the depth D of the slice in the turf is
substantially equal to the radius R of the turf slicing wheels 14,
16. In the exemplary embodiment of the underground cable laying
apparatus 10, having the turf slicing wheels 14, 16 attached to the
mounting yoke 12 by hubs 13, 15 having a 3'' diameter, the depth D
is reduced only by the relatively small radius r of the hubs 13,
15. In other embodiments of the invention, having smaller hubs, or
essentially hub-less attachments of the turf slicing wheels to a
mounting yoke, the turf slicing wheels may be lowered even further
into the ground, to a point where the contact point 61 between the
turf slicing wheels 14, 16 lies virtually at ground level G, with
the resultant depth D of the slice in the turf having a depth
virtually identical to the radius R of the turf slicing wheels 14,
16.
[0068] By way of comparison, as shown in FIG. 7a, and as previously
discussed in the Background section above, the point of contact C
in a seed-planting apparatus is typically positioned much farther
below the axis B of the a coulter of the seed-planting apparatus,
such that the point of contact C is typically located at a much
larger angle E down from the horizontal extension of the axis B
than is utilized in practicing the present invention. For example,
as previously stated above, seed-planting apparatuses typically
position the point of contact C at an angle E of 35.degree. to
55.degree. below the horizontal extension of the axis B, such that,
when the seed-planting apparatus is operated with the point of
contact C located substantially at ground level, the depth D of the
furrow formed will be substantially less then the radius R of the
coulter of the seed-planting apparatus.
[0069] As shown in FIG. 8b, by virtue of the pair of turf slicing
wheels 14, 16, of the exemplary embodiment 10, being angularly
displaced relative to one another along a vertical axis of the
mounting yoke, in the manner illustrated in FIGS. 3 and 8b, the
forward contact area 62 extends substantially downward from the
point of contact 61, with the outer peripheries of the turf slicing
wheels 14, 16 diverging below the forward contact area 62, in such
a manner that the slit in the turf has a defined horizontally
extending bottom width W thereof, as shown in FIGS. 8b and 8c. The
shape of the slit in the turf, created by the turf slicing wheels
14, 16 of the exemplary embodiment of the apparatus 10, according
to the invention, thus has a substantially different shape than the
V-shaped furrow of the type created by seed-planting equipment, as
illustrated in FIG. 7b. For purposes of illustration, FIGS. 7b, 8b
and 8c are all shown in the same relative scale, with the depth D
of the slit shown in 8b and 8c as created according to the present
invention being illustrated at a relative depth D of approximately
6'' below the surface of the ground G and the depth D of the
V-shaped furrow of FIG. 7b being illustrated at a representative
depth of approximately 3''.
[0070] A comparison of FIGS. 8b and 8c with FIG. 7b also serves to
illustrate other differences between the slit and turf created
through practice of the present invention, as compared to the
V-shaped furrow created in non-turf bearing soil of the type
created by typical seed-planting equipment. As shown in FIG. 7b,
seed planting apparatuses typically remove soil from the V-shaped
furrow and deposit it on top of the ground G in the process of
forming the V-shaped furrow. In contrast, in the slit in the turf
created through practice of the present invention, the turf is
neatly sliced by the forward contact area 62 of the turf slicing
wheels 14, 16, and the turf is separated far enough, as the turf
slicing wheels 14, 16 move forward, to allow the cable 68 to be
inserted aft of the turf slicing wheels 14, 16. Because of the
resilient nature of the turf, soil from the slit in the turf is not
brought up and deposited on top of the ground, as is the case in
seed-planting apparatuses. The soil is held in place by the turf
and its roots, substantially within the slice in the turf. As
illustrated in FIG. 8b, as the turf cutting wheels 14, 16 move
through the soil, the initial slit is widened by the angled
position of the turf slicing wheels 14, 16, and although the turf
tends to rise upward somewhat behind the hubs 13, 15, soil is not
removed from the slit and deposited on top of the ground.
[0071] In practicing the invention, it is preferable that the turf
be well watered, to enhance its capability to be spread apart,
without having dry loose dirt particles brought up onto the surface
of the ground, and also to be more readily compacted over the
cable, after the cable has been deposited in the bottom of the
slice in the turf.
[0072] As may be seen from the rear isometric view of FIG. 4, the
cable feed guide wheel 46 is positioned to dispense the cable to be
laid in the center of the slit in the turf created by turf slicing
wheels 14, 16, prior to the application of the closing force on the
slit by turf closing wheels 22, 24.
[0073] In operation, the apparatus 10 is lowered by the vehicle so
that the contact area 62 of the turf slicing wheels contacts the
upper surface 64 of the turf with the contact point 61 located
substantially at the surface G of the ground. As the vehicle
travels across the turf, rotation of the turf slicing wheels 14, 16
creates the slit in the turf that preferably opens both
horizontally and vertically to receive the cable to be laid
therein. Since the turf closure wheels 22, 24 are displaced
horizontally from one another by an amount greater than the maximum
slit width, the wheels 22, 24 ride on the outside of the slit and
provide a downward and inward closure force to effectuate a closure
of the slit once the cable has been laid therein. The amount of
force applied on the sides of the slit is dependent upon the
setting of the spring force of the turf follower spring 52 as
discussed above. Also, due to the close proximity of the turf
closure wheels 22, 24 to the rearward edge of the turf slicing
wheels 14, 16, closure of the slit into which the cable has been
laid occurs in very close proximity to the point where the cable
leaves the cable feed guide wheel. In this way, the proper
positioning of the cable within the slit is ensured. With prior
trencher systems, coils in the cable may allow the cable to rise
above the bottom of the trench before the soil is placed back in
the trench, resulting in areas where the cable is shallower than in
others, which may result in uncovering of the cable and forming a
hazardous condition.
[0074] As discussed briefly above, to ensure that the cable is
properly positioned within the slit in the turf, in the exemplary
embodiment of the cable laying apparatus 10, a cable feed guide
wheel 46 is used. However, one skilled in the art will recognize
that a roller or other guide mechanism may be used at this location
such as the alternate embodiment discussed below in relation to
FIGS. 9-15, to provide proper placement and smooth transitioning of
the cable from the cable feed tube to its position in the bottom of
the slit.
[0075] In an embodiment that utilizes a cable feed guide wheel 26,
such as that illustrated in FIG. 6, the provision of a guide wheel
cleaning mechanism may be desired. As introduced above, this
cleaning mechanism may include a cable groove cleaning rod 50 that
rides in the groove 48 of the cable feed guide wheel 46. As the
wheel rotates while dispensing the cable 68 any dirt or other
debris that may accumulate within groove 48 will be displaced by
the cleaning rod 50. Similarly, the cable feed guide wheel housing
70 may include wheel edge scrapers 72, 74 that clean the sides of
the wheel 46 and prevent the accumulation of soil or other debris,
which may affect the ability of the wheel 46 to rotate.
[0076] In practicing the invention, a cable feed guide may take a
variety of forms other than the grooved cable guide wheel 46
described above. For example, FIG. 9 illustrates a cable guide
wheel or roller 80 which does not include the groove 48 of the
embodiment of the cable feed guide wheel 46. Generally speaking, so
long as the cable feed guide element used in practicing the
invention presents a non-convex, i.e. flat or downwardly opening
concave surface, acting against the upper surface of the cable 68,
the cable feed guide will serve to hold the cable 68 in proper
position in the bottom of the slit prior to the slit being closed
by the turf closing wheels 24, 26.
[0077] FIGS. 10 and 11 illustrate alternate embodiments of a cable
guide wheel or roller (46, 80) formed from a material, or
configured in a manner that the surface of the wheel or roller may
deform about the upper surface of the cable 68. Cable guide wheels
or rollers formed from a resilient material provide an additional
advantage in that they tend to inherently shed dirt from the
outside surfaces thereof, as the wheel or roller flexes.
[0078] FIGS. 12 and 13 illustrate an alternate embodiment of the
invention, in which the feed tube 36 includes a static cable feed
guide 82, attached to the cable feed guide tube outlet 42, for
directing the cable 68 in a horizontal direction for discharge into
the slit in the turf. As best seen in FIG. 13, the static cable
feed guide 82 defines a downwardly opening substantially concave
surface 84 adapted for contacting the upper surface of the cable
68, with the downwardly opening concave surface 84 being configured
to preclude having the cable 68 escape from the concave surface
84.
[0079] FIG. 14 illustrates an alternate embodiment of a cable feed
guide 86, according to the invention, in the form of a flexible
tubular shaped extension of the cable feed tube 36 having a bore
therein, for directing the cable 68 into the slit in a horizontal
direction, while the flexible tube extension 86 is being bent into
a horizontal arc by contact between the bottom of the flexible tube
extension and the bottom surface W of the slit in the turf. For
such an embodiment, it is contemplated that the flexible tube
extension may be made from a polymer or composite material, having
sufficient bending stiffness to hold the cable 68 securely in the
bottom of the slit in the turf.
[0080] FIG. 15 illustrates a variation of the alternate embodiment
of the invention shown in FIG. 14, in which an underground laying
apparatus 10, according to the invention, includes a flexible tube
extension 88 which extends through the full length of the cable
feed tube 36, and is secured therein by a projecting flange 90, at
the inlet to the cable feed tube, with a portion of the flexible
tube 88 extending beyond the outlet end of the cable feed tube 36.
With this embodiment of the invention, the flexible feed tube
extension provides a continuous smooth surface from the inlet to
the outlet of the cable feed tube, in a form that may be readily
replaced, as the flexible tube extension becomes worn.
Alternatively, a selection of different flexible tube extensions
88, each having, respectively, bores thereof sized and/or
appropriately shaped to accommodate various sizes and types of
cable, wire, tubing, etc. to be installed with the cable laying
machine 10 may be provided, to tailor the configuration of the feed
tube 36 and cable feed guide to the particular type of cable and/or
tube being installed.
[0081] FIG. 16 illustrates an alternate embodiment of the closure
wheels 22, 24 of the exemplary embodiment of the underground cable
laying apparatus 10. In the alternate embodiment of the turf
closing wheels 22, 24, shown in FIG. 16, the outer periphery of the
turf closing wheels 24, 26 is configured to form a wide, flat area
of contact with the turf, which may be more advantageous than the
more rounded shape of the embodiment of the turf closing wheels 22,
24 shown in FIG. 4, for certain conditions of the turf, such as
when the turf is relatively wet or somewhat sparse. In other
embodiments of the invention, the turf closing wheels may have yet
other configurations. Turf closing structures, having appropriate
configurations other than wheels may also be used in practicing the
invention, in combination with other aspects of the invention.
[0082] The underground cable laying apparatus of the present
invention provides significant advantage through the use of the
turf slicing wheels, particularly in installation locations where
other installed underground systems may be in place, and where a
visible scar in the turf resulting from the cable laying operation
is not desired. In the first instance, the apparatus of the present
invention provides a significant advantage through the use of the
rotating turf slicing wheels for providing the slit in the turf
into which the cable is to be laid. Since the turf slicing wheels
rotate, there is a significantly reduced likelihood of damage to
other installed underground systems as results from typical
trenchers. Specifically, the rotating turf slicing wheels will not
snag and pull the other underground systems which it encounters,
and instead merely rolls over them while leaving them in place.
This non-damaging contact with previously installed underground
systems is aided by the angular relationship between the two turf
slicing wheels. That is, the relative angular displacement of the
turf slicing wheels forms a contact portion 62 that slices the top
layer of the turf, but then separate from one another at all other
locations. As a result, contact with previously installed
underground systems often occurs at a position where the turf
slicing wheels 14, 16 are separated from one another, but are still
in close proximity. As a result, the contact force is dispersed at
the two contact points with each of the individual turf slicing
wheels. Since these wheels are most likely still in close
proximity, the contact force is not sufficient to damage the
exterior surface of the previously installed underground
system.
[0083] In the second instance, unlike blade type systems that gouge
a slit into the turf, and trencher systems that completely remove
the soil to form a trench, the underground cable laying apparatus
of the present invention merely opens a slit in the turf, which is
quickly reclosed once the cable has been placed therein. The
angular placement of the turf slicing wheels ensures a narrow slit
is initiated in the turf, is slightly widened to allow placement of
the cable therein, and then is immediately reclosed by providing
angular downward and inward force on the sides of the slit opened
by the turf slicing wheels. As a result, it is nearly impossible to
observe where the slit was opened in the turf once the cable has
been laid therein. This is especially true when the turf is moist,
or has been recently watered.
[0084] Experience has shown that the present invention may be
practiced in a wide variety of soil types and turf conditions. It
is preferred, when practicing the invention, that the turf be
generally well watered, so that the soil is moist down to the depth
D of the slit below the surface of the ground G. Accordingly, it
may be desirable in practicing the invention, to water the turf
prior to installing the cable therein.
[0085] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference to
the same extent as if each reference were individually and
specifically indicated to be incorporated by reference and were set
forth in its entirety herein.
[0086] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the invention (especially in
the context of the following claims) is to be construed to cover
both the singular and the plural, unless otherwise indicated herein
or clearly contradicted by context. The terms "comprising,"
"having," "including," and "containing" are to be construed as
open-ended terms (i.e., meaning "including, but not limited to,")
unless otherwise noted. Recitation of ranges of values herein are
merely intended to serve as a shorthand method of referring
individually to each separate value falling within the range,
unless otherwise indicated herein, and each separate value is
incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
claimed. No language in the specification should be construed as
indicating any non-claimed element as essential to the practice of
the invention.
[0087] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the invention to be practiced otherwise than as specifically
described herein. Accordingly, this invention includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *