Note: Descriptions are shown in the official language in which they were submitted.
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SELF-PROPELLED DRILLING VEHICLE
BACKGROUND
(a) Field
[0001] The subject matter disclosed generally relates to apparatus and
devices used in a drilling environment, and more specifically to exploration
drilling vehicles.
(b) Related Prior Art
[0002] In the field of drill exploration, one existing challenge resides
in
placing an electric exploration drilling component into place to perform a
drilling
operation. An associated challenge resides in the electrical connection of the
exploration drilling component, since it is fed with heavy high electric
voltage
cable.
[0003] One common practice to response to that challenge consists in
having a drilling exploration component being towed or transported into place
with a vehicle such as a tractor or a bulldozer to perform the drilling
operation.
Such an ensemble involves that each time the drill exploration component must
be moved to explore in another location, the tractor or the bulldozer must
return
to the drill exploration component to move it.
[0004] Another existing solution consists in having a heavy operator-
driven
vehicle comprising a Roll Over Protection System (ROPS). Since the operator is
on the vehicle driving the vehicle when the latter is moving, security
requirements
demands the presence of the ROPS. The vehicle is therefore heavy, and provide
challenges in the operation of the vehicle, for instance dimensions of the
vehicle
and the view of the environment by the operator when operating the vehicle.
[0005] There is therefore a need for improvement in the field that would
face the above challenges while overcoming at least some of the drawbacks of
the existing solutions.
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SUMMARY
[0006] According to an embodiment, there is provided a self-propelled
drilling vehicle comprising ground engaging means adapted to propel the
drilling
vehicle, a drilling rod operating assembly comprising a drilling mast, a rod
engaging means and a rod guiding means, a first engine powered by an onboard
energy source, wherein the first engine is configured to controllably drive
the
ground engaging means and the vehicle stability means, and a second engine
powered by an external energy source, wherein the second engine is configured
to controllably drive the drilling rod operating assembly
[0007] According to an aspect, the first engine comprises one of an
internal combustion engine and an electric motor.
[0008] According to an aspect, the onboard energy source comprises one
of combusting fuel and a battery pack.
[0009] According to an aspect, the onboard energy source comprises a
battery pack, and wherein the self-propelled drilling vehicle is adapted to
recharge the battery pack when the second engine is connected to the external
energy source.
[0010] According to an aspect, the second engine comprises an electric
motor.
[0011] According to an aspect, the drilling vehicle further comprises a
releasable connection, wherein the external energy source is transmitted to
the
second engine through the releasable connection.
[0012] According to an aspect, the ground engaging means comprises at
least one of wheels, tires and tracks.
[0013] According to an aspect, the ground engaging means comprises at
least two independently driven propelling components, for driving
independently
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the at least two independently driven propelling components to steer the self-
propelled drilling vehicle.
[0014] According to an aspect, the drilling vehicle further comprises a
remote controller controlling power transmitted to the ground engaging means.
[0015] According to an aspect, the remote controller comprises a first
controller component mounted to the self-propelled drilling vehicle and a
second
controller component, in communication with the first controller component,
configured to be operated remotely from the self-propelled drilling vehicle.
[0016] According to an aspect, the first controller component and the
second controller component comprise one of WiFi communication capability,
Bluetooth communication capability, infrared communication capability, and
radio
frequency communication capability.
[0017] According to an aspect, the first engine and the second engine are
adapted to power a hydraulic system, wherein the hydraulic system is adapted
to
controllably power accessories comprising the ground engaging means when the
second engine is not powered up, and powering accessories and the drilling rod
driving means when the second engine is powered up.
[0018] According to an aspect, the accessories further comprise one of
drilling vehicle stability means, a drilling mast positioning cylinder and a
counter-
acting jack.
[0019] According to an aspect, the drilling vehicle further comprises a
frame to which are mounted the ground engaging means, the first engine, the
second engine and the drilling rod driving means.
[0020] According to an aspect, the drilling vehicle further comprises
harnessing means, wherein the harnessing means is adapted to one of
releasably attach a power cable to the self-propelled drilling vehicle and
releasably attach the self-propelled driving vehicle to a towing vehicle.
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[0021] According to an aspect, the drilling rod driving means comprises a
drilling mast controllably orientable between a moving configuration and an
operating configuration, wherein the moving configuration is more compact than
in the operating configuration.
[0022] According to an aspect, the ground engaging means have a
maximum height relatively to the ground, and wherein a center of gravity of
the
self-propelled drilling vehicle is lower than the maximum height of the ground
engaging means.
[0023] According to an aspect, the drilling vehicle further comprises a
frame, wherein the drilling rod driving means, the first engine and the second
engine are mounted to the frame, and wherein the drilling rod driving means is
mounted to the frame at a position distant from at least one of the first
engine
and the second engine.
[0024] According to an aspect, the first engine is adapted to provide a
first
output power, the second engine is adapted to provide a second output power
and wherein a power ratio between the first output power and the second output
power is about between 3 to 4 and 1 to 3.
[0025] According to another embodiment, there is provided a self-
propelled drilling vehicle comprising a ground engaging means configured to
propel the self-propelled drilling vehicle, a drilling rod driving means
configured to
operate a drilling rod, a first engine powered by an onboard energy source,
wherein the first engine is configured to controllably drive the ground
engaging
means, and a second engine powered by an external energy source, wherein the
second engine is configured to power the drilling rod driving means.
[0026] According to another embodiment, there is provided a self-
propelled drilling vehicle adapted for operating a drilling rod driving means
to be
mounted thereto, the drilling rod driving means being adapted for operating a
drilling rod. The drilling vehicle comprises a ground engaging means
configured
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to propel the self-propelled exploration drilling vehicle, a first engine
powered by
an onboard energy source, wherein the first engine is configured to
controllably
drive the ground engaging means, and a second engine powered by an external
energy source, wherein the second engine is configured to power the drilling
rod
driving means.
[0027] Features and advantages of the subject matter hereof will become
more apparent in light of the following detailed description of selected
embodiments, as illustrated in the accompanying figures. As will be realized,
the
subject matter disclosed and claimed is capable of modifications in various
respects, all without departing from the scope of the claims. Accordingly, the
drawings and the description are to be regarded as illustrative in nature, and
not
as restrictive and the full scope of the subject matter is set forth in the
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Further features and advantages of the present disclosure will
become apparent from the following detailed description, taken in combination
with the appended drawings, in which:
[0029] Fig. 1 illustrates a perspective elevated view of a self-propelled
drilling vehicle according to an embodiment;
[0030] Fig. 2 illustrates a perspective elevated view of a self-propelled
drilling vehicle in an operating configuration according to an embodiment;
[0031] Fig. 3 illustrates a perspective elevated view of a self-propelled
drilling vehicle in an operating configuration according to an embodiment;
[0032] Fig. 4 illustrates a perspective exploded view of an embodiment of
a self-propelled drilling vehicle;
[0033] Fig. 5 illustrates a perspective elevated view of a frame of an
embodiment of the self-propelled drilling vehicle;
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[0034] Figs. 6A and 6B illustrate top views of embodiments a self-
propelled drilling vehicle, the illustrated embodiments schematically
illustrating a
range of operating configurations available to perform in;
[0035] Fig. 7 illustrates a rear view of a self-propelled drilling
vehicle
schematically illustrating a range of operating configurations of an
embodiment of
the self-propelled drilling vehicle; and
[0036] Fig. 8 is a schematically illustration of a hydraulic circuit of
an
embodiment of the self-propelled drilling vehicle.
[0037] It will be noted that throughout the appended drawings, like
features are identified by like reference numerals.
DETAILED DESCRIPTION
[0038] Embodiments of self-propelled drilling vehicles are disclosed, and
more particularly self-propelled drilling vehicles adapted to be able to
autonomously move to and between operations location(s) and to perform
exploration processes, namely low-depth and medium-depth drilling operations.
[0039] The present invention will be more readily understood by referring
to the following examples which are given to illustrate the invention rather
than to
limit its scope.
[0040] Referring now to the drawings, and more particularly to Fig. 1, an
embodiment of a self-propelled drilling vehicle 10 comprises a frame 20, a set
of
wheels 30 mounted to the frame 20, and a drilling rod driving means 38,
comprising a rod engaging means 374 and a rod guiding means 375. The drilling
rod driving means 38, mounted to a drilling mast 40, is adapted to drive a
drilling
rod (not shown) when performing drilling operations. The wheels 30, in
cooperation with the tires (308 ¨ Fig. 2) mounted thereto, define ground
engaging
means that, when driven, are adapted to propel the self-propelled drilling
vehicle
10. The self-propelled drilling vehicle 10 is further equipped with a series
of
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engines and a hydraulic system 50, the functions of which will be explained
further in details in relation to the following drawings.
[0041] Now referring additionally to Fig. 2, the self-propelled drilling
vehicle
comprises four wheels 30, two front wheels and two back wheels, with a pair
on each side of the frame 20; the four (4) wheels 30 perform together as a
ground engaging means and are able, when driven, to propel the self-propelled
drilling vehicle 10 forth, back and to turn the self-propelled drilling
vehicle 10.
The wheels 30 are each adapted to mount twin tires 308, or in an alternate
embodiment (not shown) wide tires. Further, in an alternate embodiment (not
shown), specifically designed wheels are used; these wheels are adapted to
engage directly with the ground beneath. In another alternate embodiment (not
shown), tracks are mounted on each side of the frame 20 to the wheels 30. The
tracks are engaging with the ground. For each track, at least one driven wheel
30
per side of the self-propelled drilling vehicle 10 drives the track and thus
participate in propelling the self-propelled drilling vehicle 10.
[0042] Back to Fig. 1, the self-propelled drilling vehicle 10 is equipped
with
a towing structure 106 that may be releasably attached at one end to the self-
propelled drilling vehicle 10 and at the other end to a towing vehicle (not
shown)
to tow the self-propelled drilling vehicle 10 over long distances and/or for
fast
displacements that would exceed the speed capability of the self-propelled
drilling vehicle 10.
[0043] In Fig. 1, the self-propelled drilling vehicle 10 is illustrated
in a
moving, or compact, configuration, wherein the moving section area, or pass-
through area, defining the minimum dimensions of a tunnel for instance for the
self-propelled drilling vehicle 10 to pass through, is at a minimum. The self-
propelled drilling vehicle 10 will therefore have the capability to drive
through
relatively small tunnels and other passages having relatively small openings.
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[0044] In Fig. 2, the self-propelled drilling vehicle 10 is illustrated
in an
operating configuration, wherein the moving section area, or pass-through
area,
is greater than in its moving configuration. The operating configuration in
Fig. 2
features the drilling vehicle in contact with the ground over the tires 308.
In Fig. 3,
the self-propelled drilling vehicle 10 is illustrated in another operating
configuration in which the self-propelled drilling vehicle 10 is raised above
the
ground over four (4) hydraulic jacks 449 defining a drilling vehicle stability
means.
In Figs. 1 and 3, the drilling mast 40 is illustrated having moved from a
moving
configuration (see Fig. 1) to an operating configuration (see Figs. 1 and 3)
where
a drilling rod (not illustrated) may be driven by the drilling rod driving
means 38
into the ground to drill an exploration hole at some distance from the frame
20. In
an assembled perspective, a drilling rod operating assembly (not numbered)
comprises the drilling mast 40, a rod engaging means 374 and a rod guiding
means 375. To move the drilling mast 40 between moving and operating
configurations, and further between different operating configurations,
positioning
cylinders, among which the positioning cylinder 480 illustrated in Figs. 1 and
3,
operate on the drilling mast 40 to potentially change both positions and
orientations of the drilling mast 40 according to exploration requirements.
[0045] One must note that drilling vehicle requirements for an operating
configuration versus another may vary. Figs. 1 and 3 differ in the self-
propelled
drilling vehicle 10 being in contact with the ground through the tires 308 or
through the bottom extremity of the hydraulic jacks 449. Requirements for
operating conditions may also involve additional components such as means for
stabilization of the drilling mast 40, for example a mast stabilizer in the
form of
counter-acting hydraulic jacks, a.k.a. ram jacks (not shown) located at an
opposite end of the drilling mast 40 pressing over a solid surface opposed to
the
intended drilling direction or with mast mounting plate which is being bolted
into
the ground or the surface to be drilled. It must, therefore, be understood
that
operating configurations comprise any configuration of the self-propelled
drilling
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vehicle 10 wherein safety and operating requirements are respected and wherein
the drilling rod driving means 38 is able to operate a drilling rod to perform
a
drilling operation.
[0046] Back to Fig. 2, the self-propelled drilling vehicle 10 comprises a
housing 3 mounted to the frame 20. According to an embodiment, the frame
defines a longitudinal axis defining a general orientation according
substantially
to which the wheels 30 are adapted to propel the self-propelled drilling
vehicle
10. Substantially to one extremity of the frame 20 is mounted the drilling
mast 40,
while substantially to the other extremity is mounted the housing 3 configured
as
a cage housing mechanical components of the self-propelled drilling vehicle
10.
[0047] The mechanical components comprise a first engine, which
according to the illustrated embodiment is a diesel engine 134, and an onboard
energy-stocking component, illustrated as a diesel fuel tank 278. The first
engine
is configured to operate in cooperation with the energy-stocking component so
that the first engine may operate using the onboard energy source available in
the energy-stocking component. In the illustrated embodiment, the diesel
engine
134 is fluidly connected to diesel fuel tank 278.
[0048] The mechanical components further comprise a second engine,
namely an electric motor 1. The second engine is able to operate when
connected to a vehicle-external power source. According to an embodiment, the
electric motor is adapted to be fed with electric alternating current of
between
400-1000 volts through a feeding power cable 85 (see Fig. 8) connected at its
other extremity to a power grid, a generator, or any other available and
appropriate electrical power source (not shown).
[0049] The self-propelled drilling vehicle 10 further comprises a
hydraulic
system (see Figs. 4 and 5) driven by at least one of the first engine and the
second engine. The self-propelled drilling vehicle 10 illustrated further
comprises
an electric box 44, a series of hydraulic valves 312 and a hydraulic block
360.
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[0050] Now referring additionally to Fig. 4, the exploded view
illustrates the
configurations of the components of the self-propelled drilling vehicle 10,
which
results in the self-propelled drilling vehicle 10 combining an auto-propelling
capability, a very low moving section area, or pass-through area, requirement
and a very low vertical gravity center.
[0051] The exploded view of the self-propelled drilling vehicle 10 of
Fig. 4
shows the electric motor 1, the diesel engine 134 and the diesel fuel tank 278
outside the housing 3 while respecting the height of these components when in
an operating configuration. One must note that the housing 3 features side
openings 32 on both sides for improved serviceability. Typically, the side
openings 32 are closed with grid doors (see Fig. 1) to prevent foreign objects
from entering into contact with any of the electric motor 1 and the diesel
engine
134 when in operation while ensuring efficient ventilation inside the housing
3.
The embodiment of Fig. 4 comprises additional components, namely a liquid tank
and a hydraulic pump (see Fig. 8), not shown in that view, operating in
combination with the diesel engine 134. One must note that the heaviest
components, namely the electric motor, the liquid tank, hydraulic pump 295,
and
the diesel fuel tank 278 are located substantially close to the bottom of the
housing 3; the diesel engine 134 and additional serviceable components (not
identified specifically) being located above these other components. This
configuration is specifically chosen as lowering in an optimum manner the
center
of gravity of the components. Furthermore, the housing 3 extends according to
its
bottom at a level substantially equivalent to the bottom level of the frame 20
relatively to the ground. That configuration once again optimizes the gravity
center of the self-propelled drilling vehicle 10 at its lowest possible
position.
[0052] According to an embodiment, the center of gravity of the self-
propelled drilling vehicle 10 is lower than the maximum height of the ground
engaging means, namely the height of the tires 308.
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[0053] According to an embodiment, the center of gravity of the self-
propelled drilling vehicle 10 is lower than half the maximum height of the
ground
engaging means, namely the height of the tires 308.
[0054] According to an embodiment, the electric motor 1 and the diesel
engine 134 both power a distinct hydraulic pump part of the hydraulic system.
The diesel engine 134 powers a hydraulic pump 295 (not shown in the figure and
schematically illustrated on Fig. 8 as hydraulic pump 295). The electric motor
1
powers a hydraulic pump (not shown on the figure, schematically illustrated as
pump 2 in Fig. 8). The diesel engine 134 is conceived to provide the necessary
power to power a setup phase, while the electric motor 1 is capable of
providing
the power necessary to perform any operation of the self-propelled drilling
vehicle 10 during the operating phase, or out of the operating phase as long
as
the electric motor 1 is electrically connected to a proper power source.
[0055] Accordingly, for explanatory purposes, firstly for the operation of
the
self-propelled drilling vehicle 10 a setup phase takes place during which the
self-
propelled drilling vehicle 10 is disconnected from any proper power source. In
consequence, during the setup phase, the only energy source available for
operating the self-propelled drilling vehicle 10 is the onboard energy source,
namely the diesel fuel contained in the diesel fuel tank 278. Actions
performed
during the setup phase include displacement of the self-propelled drilling
vehicle
to an operating location, raising the self-propelled drilling vehicle 10 on
the
hydraulic jacks 449, moving the drilling mast in an operating position, etc.
[0056] Typically, when the self-propelled drilling vehicle 10 is self-
propelled using the diesel engine 134, an electric cable is releasably
attached to
the self-propelled drilling vehicle 10 using a harness, a hook or any other
alternate component configured to secure releasably a section of the electric
cable. Therefore, the extremity of the electric cable can be pulled by the
moving
self-propelled drilling vehicle 10. Once stopped, the electric cable can be
detached from the harness and connected to the electric motor 1. Hence
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operators do not have to pull manually, or use another pulling device, to
carry the
heavy electric cable behind the self-propelled drilling vehicle 10. Operators
rather only have to handle the extremity of the electric cable to connect it
to the
electric motor 1. However, it is to be understood that the electric cable can
be
releasably detached from the self-propelled drilling vehicle 10 during the
movement of said vehicle or during the setup phase.
[0057] Thus, during or at the end of the setup phase, the electrical
cable is
connected to the electric motor 1 to power up the electric motor 1. Once
connected, the electric motor 1, through its hydraulic pump, may provide power
to complete the setup phase, or may provide power to perform actions of the
operating phase. Specifically, the operating phase consists in exploration
drilling.
Thus, the hydraulic pump, powered by the electric motor 1, powers the drilling
rod driving means 38 which drive the drilling rod (not shown) into the ground
for
exploration drilling.
[0058] At the end of the operating phase, based on the requirements
associated with placing the self-propelled drilling vehicle 10 into a new
operating
configuration, and more specifically regarding if it is necessary to
disconnect the
electric cable from the electric motor 1 that would disconnect the electric
motor 1
from the electric power source, accessories such as the wheels 30, the
hydraulic
jacks 449 and the positioning cylinders 480 may be powered by either the
diesel
engine 134 or the electric motor 1.
[0059] Still on Fig. 4, one must see that the drilling mast 40 is mounted
to
the frame over a series of rotatable and pivotal plates. Such a solution
allows the
drilling mast 40 to take place in a plurality of operating positions while the
self-
propelled drilling vehicle 10 remains at the same location. Figs. 6A and 6B,
and 7
provide examples of the range of operating positions of the drilling mast 40.
[0060] Now referring additionally to Fig. 5, the frame 20 houses a
hydraulic
fluid tank 306 integral to the frame 20. The hydraulic fluid tank 306 is
adapted to
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hold a substantial portion of the fluid used by the hydraulic system, thus
necessary for operating of self-propelled drilling vehicle 10. It must be
noted that
once again the self-propelled drilling vehicle 10 is configured so as to
optimize
the height of the center of gravity of its components. It is further designed
to
optimize the serviceability of the components, having the low-service
requirement
heavy components located under the higher-service requirement lighter
components. The hydraulic fluid tank 306 is thus located at the bottom of the
frame 20, with serviceable lighter components, namely valves, pipes, etc.,
located above.
[0061] The illustration of the frame of Fig. 5 shows four (4) openings
302
on the sides the frame 20 for the wheels 30. The openings 302 are for
releasable
mounting the wheels 30 on the frame 20. The wheels 30 are hydraulically driven
planetary wheel drives. So, by controllably transmitting fluid to one of the
wheels
30, an operator drives the tire 308 mounted on the specific wheel to engage
the
ground. By controlling the flow of hydraulic fluid individually for each one
of the
four (4) wheels, the operator controls both the direction (back vs forth) and
its
orientation (the self-propelled drilling vehicle 10 turning left vs moving
straight
ahead vs turning right). For instance, by having the right wheels driven
forward
while blocking the left wheels, the operator forces the self-propelled
drilling
vehicle 10 to turn left. Thus, even though the illustrated wheels 30 have no
steering capability, by driving differently and independently the wheels, the
solution provides a steering capability for the self-propelled drilling
vehicle 10.
[0062] The self-propelled drilling vehicle is configured to be remotely
operated. Practically, it involves an operator verifying the operating state
of the
self-propelled drilling vehicle 10 and the electric cable being appropriately
attached to the self-propelled drilling vehicle 10. It further comprises the
operator
powering up the diesel engine 134. Afterward, the operator controls, using a
remote control (not shown), the accessories, namely the wheels, the
stabilization
jacks, etc. for the setup phase. The operator may be at some distance from the
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self-propelled drilling vehicle 10, for example, one hundred (100) feet,
during the
operation, ensuring its safety. Such a remote control comprises a first
controller
component 91 (see Fig. 8), illustrated in a perspective view as located in the
electric box 44, mounted to the self-propelled drilling vehicle 10, and a
second
controller component 92 (see Fig. 8), in communication with the first
controller
component 91 and configured to be operated remotely from the drilling vehicle
by
an operator. The first controller component 91 and the second controller
component 92 operate cooperatively as a controller 90 in operating
communication with hydraulic controls as illustrated on Fig. 8.
[0063] The technology used to remotely control the drilling vehicle may
vary according to embodiments. Exemplary embodiments involve use of a cable-
linked remote control, or the first and second controller components having
WiFi
communication capability, Bluetooth communication capability, infrared
communication capability, or radio communication capability without any
physical
component linking them.
[0064] According to another embodiment (not shown), the first engine is
an electric motor and the onboard energy source is a battery pack. With that
embodiment, the electric motor powered by the battery pack powers the
accessories, comprising the ground engaging means. When the second engine,
namely the electric motor 1, is connected to a power source, the electricity
from
the electric cable is used to power the electric motor and to charge the
battery
pack. Though, the battery pack is always charged at the end of an operating
phase.
[0065] According to an embodiment, the ratio of output power of the first
engine and the second engine is about between 3 to 4 to 1 to 3. According to
an
embodiment, the maximum output power of the first engine is between about 49
and 100 HP (horsepower). The maximum output power of the second engine in
between about 100 HP and 150 HP.
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[0066] According to an embodiment, the self-propelled drilling vehicle is
adapted for a drilling mast to be mounted thereto, including fluidly connected
to
the hydraulic system. Once the drilling mast mounted, the drilling vehicle is
adapted to perform drilling operations, for example exploration drilling
operations.
[0067] Fig. 8 schematically illustrates the hydraulic circuit of the self-
propelled drilling vehicle 10 with engines powering it. First, either one of
the
diesel engine 134 and the electric motor 1 powers the hydraulic system 50;
that
is, for the diesel engine 134, the hydraulic pump 295, and, for the electric
motor
1, the hydraulic pump 2. The hydraulic pump 2 is fluidly connected to the
hydraulic fluid tank 306 and to the controls 51 which are operated to
controllably
drive the fluid either to the drilling rod driving means 38 or to the
accessories
such as the wheels 30. The hydraulic pump 295 is fluidly connected to the
hydraulic fluid tank 306 and to a controller. The hydraulic pump 295 is
operated
to controllably drive the fluid to the accessories such as the wheels 30.
[0068] It is to be noted that the hydraulic system is schematically
illustrated therethrough and many details are omitted. For instance, the use
of
electronically control valves connected to the controller, the use of one-way
valve
to ensure operation of the system regardless of the engine operating on the
hydraulic circuit, the use directional control valves, etc.
[0069] While preferred embodiments have been described above and
illustrated in the accompanying drawings, it will be evident to those skilled
in the
art that modifications may be made without departing from this disclosure.
Such
modifications are considered as possible variants comprised in the scope of
the
disclosure.
