Note: Descriptions are shown in the official language in which they were submitted.
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SCREEN-HANDLING SYSTEM AND METHOD OF INSTALLING
SCREENING ON A ROCK FACE
TECHNICAL FIELD
[0001] The present invention relates generally to mining
equipment and, in particular, to rock bolting and screening.
BACKGROUND
[0002] In a mine, ground support, e.g. rock bolts and
screening, is used to prevent rock falls. Several different
types of rock bolts may be used but all require that holes be
drilled in the rock first. This is
done with equipment known
as rock bolters. These are mobile units with a bolting head
attached. To drill
a hole in the rock to install ground
support, the bolting head is placed against the rock face
(which is called "stinging the face") and then a hole is
drilled into the rock. The unit is then indexed to install
the ground support such as screening. As is
known in the
mining industry, wire mesh screening is installed in mines to
prevent loose rocks from falling.
[0003] Using conventional technologies, the installation of
screening has been found to be problematic. Known equipment
is generally complex, expensive and prone to breakdown. A
need therefore exists for an improved technology for
installing screening on a rock face in a mine.
SUMMARY
[0004] In general, the present invention provides a novel
screen handling system (also referred to herein as a "screen
handler") and a novel method of installing screening. The
screen handler (screen-handling system) has an actuator
incorporated within a stinger. The actuator causes a screen-
engaging finger (or stem) to extend and retract relative to
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the stinger. The finger engages or hooks the screen and then
the actuator retracts (pulls) the screen snugly against the
outer face of a stinger pad of the stinger. The
screen,
clamped against the outer face of the stinger pad, can thus be
manipulated (e.g. displaced or rotated). The screen is then
placed against the rock face in a mine. Rock bolts may then
be used to fasten the screen to the rock face.
[0005] Accordingly, one aspect of the present invention is a
screen handler (or screen-handling system or screen-handling
stinger) that includes a hydraulic stinger having a bore, a
screen-handling actuator disposed within the bore of the
hydraulic stinger for extending and retracting relative to the
stinger, and a screen-engaging finger connected to a movable
forward end of the actuator to engage a screen.
[0006] Another
aspect of the present invention is a method of
installing screening on a rock face. The
method entails
providing a screen-handling stinger having a screen-handling
actuator disposed within a bore of the stinger, extending the
screen-handling actuator relative to the stinger such that a
screen-engaging finger connected to a movable forward end of
the actuator hooks onto a screen, retracting the screen-
handling actuator until the screen abuts a stinger pad of the
hydraulic stinger, and bolting the screen to the rock face.
[0007] Yet
another aspect of the present invention is a rock
bolting and screen-installing system comprising a drill feed
for drilling a hole in a rock face, a bolting feed for
installing a rock bolt into the hole, a screen-handling
stinger for stinging a rock face to stabilize the system when
drilling, wherein the stinger comprises a bore and a screen-
handling actuator disposed within the bore of the stinger for
extending and retracting relative to the stinger.
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[0008] Yet a further aspect of the present invention is a
screen handler for handling a screen. The screen handler
includes a screen-handling actuator mounted to a forward end
of a feed rail and a screen-engaging finger connected to a
forward movable end of the actuator for engaging the screen
and for retracting the screen against a pad disposed at a
forward end of the screen handler.
BRIEF DESCRIPTION OF THE DRAWINGS
[0MOS] Further features and advantages of the present
invention will become apparent from the following detailed
description, taken in combination with the appended drawings,
in which:
[0010] FIG. 1 is an isometric view of a screen handler in
accordance with an embodiment of the present invention (shown
in its retracted posture);
[0011] FIG. 2 is an isometric view of the screen handler
holding a screen against a stinger pad;
(0012] FIG. 3 is a cross-sectional view of the screen handler
of FIG. 1;
[0013] FIG. 4 is a cross-sectional view of the screen handler
in an extended posture;
[0ou] FIG. 5 is an exploded assembly view of the screen
handler;
[0015] FIG. 6 is a side view of a rock bolter that includes
the screen handler;
[0016] FIG. 7 is an isometric view of a screen handler (in
its extended position) mounted to a drill feed in accordance
with another embodiment of the present invention; and
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[0017] FIG. 8
is an isometric view of the screen handler of
FIG. 7, shown in its retracted position.
[0018] It will be noted that throughout the appended
drawings, like features are identified by like reference
numerals. It
should furthermore be noted that the drawings
are not necessarily to scale.
DETAILED DESCRIPTION
[0019] By way
of introduction, the present invention provides
a screen handling system ("screen handler") and a method of
installing screening on a rock face of a mine.
V020] The
screen handler (screen-handling system or screen-
handling stinger) has a screen-handling actuator incorporated
within a central bore of a hydraulic stinger of a rock bolter.
The hybrid-function stinger thus has both the functions of a
conventional stinger (to sting the rock face to stabilize the
rock bolter for drilling and bolting) but also enables
screening to be gripped and manipulated for installation on
the rock face.
WO] The screen handler (screen-handling stinger) is
illustrated in FIG. 1. As shown in FIG. 1, the screen-
handling stinger, which is generally designated by reference
numeral 100 has two main subsystems: (i) a modified hydraulic
stinger having an internal central bore and (ii) a screen-
handling actuator subassembly that extends from and retracts
into the central bore of the stinger. The
screen-handling
stinger is thus both a stinger and a screen-handling device.
In other words, this invention may be understood as a stinger
that includes a screen-handling mechanism. For the purposes
of this specification, the term "screen handler" shall be
meant to include a mechanism that includes a stinger and a
screen-handling actuator. Similarly, the term "screen-handling
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stinger" shall mean a stinger that includes a screen-handling
mechanism.
[0On] As
depicted in FIG. 1, the screen handler (or screen-
handling stinger) 100 includes a stinger pad 101, a stinger
pivot adapter plate 102, a stinger pivot outer housing 103,
and a cylinder (actuator) retaining bracket 105 for holding a
screen-handling actuator. The
screen-handling stinger also
includes a front rotation motor adapter plate 115, a rotation
motor 116, and a rear rotation motor adapter plate 117. A
hose guide 120 may also be attached. These
various
components will be described in greater detail below. Unlike
a conventional stinger, the screen-handling stinger not only
stings a rock face but also has an internal actuator that
extends and retracts a screen-engaging finger to hold a screen
against the stinger pad as depicted in FIG. 2. This enables
the screen to be manipulated by the rock bolter to place the
screen in a desired location on a rock face. The rock bolter
then installs one or more rock bolts to secure the screen to
the rock face.
[0On] As
depicted by way of example in FIG. 2, the actuator
causes a screen-engaging finger (or stem) to extend and
retract relative to the stinger. The finger engages or hooks
the screen 50 and then the actuator retracts (pulls) the
screen snugly against the outer face of a stinger pad of the
stinger. The screen, clamped against the outer face of the
stinger pad, can thus be manipulated (e.g. displaced or
rotated). The screen is then placed against the rock face in
a mine. Rock bolts may then be used to fasten the screen to
the rock face.
[0024] SCREEN HANDLER (SCREEN-HANDLING STINGER)
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PM] The screen-handling stinger (or "screen handler" or
"screen-handling system") 100 will now be further described in
greater detail with reference to FIGS. 3-5. FIG. 3
is a
cross-sectional view of the screen-handling stinger of FIG. 1
(shown in the fully retracted posture). FIG. 4
is a cross-
sectional view of the screen-handling stinger in a fully
extended posture. As such, it is apparent from FIG. 3 and
FIG. 4 that the finger moves between a first (retracted)
position and a second (extended) position. FIG. 5
is an
exploded assembly view of the screen-handling stinger.
[0mas] As
depicted in FIGS. 3-5, the screen-handling stinger
100 includes a stinger pad 101 mounted to a stinger pivot
adaptor plate 102 which is rotationally mounted in the stinger
pivot outer housing 103 via a stinger rotation thrust bushing
104. The
bushing 104 may be retained by a retaining ring
(snap ring) 107. A seal 110 may be disposed between housing
103 and bushing 104. The outer housing 103 is mounted to a
cylinder retaining bracket 105. An 0-ring 111 is seated in a
groove in the rear face of outer housing 103 to provide a seal
between housing 103 and bracket 105. The pad
101 and the
adapter plate 102 each have a central bore through which the
screen handler (or more specifically a finger or stem of the
screen handler) may extend to engage the screen. In other
embodiments, the bore may be off-axis (not centrally
disposed). The shape of the pad may be circular as shown but
it may also have other shapes (e.g. U-shaped, X-shaped, cross-
shaped, square, rectangular, hexagonal, octagonal, etc.)
VICan The
cylinder (actuator) retaining bracket 105 retains
(or houses) the actuator subassembly 150. The
actuator
subassembly comprises a hydraulic actuator. The
actuator
includes a hydraulic cylinder and an internal hydraulically
driven piston, as well as a piston rod extending forwardly and
connecting to a finger (stem) that extends to engage or hook
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onto the screen. The
actuator assembly 150 may include a
cylinder fitting guard 127. The cylinder sits within a
cylinder guide bushing 106. A wiper
112 may be disposed
between the guide bushing 106 and the rear wall of the stinger
pad. The
wiper wipes dirt, dust, grime, etc. from the stem
(finger) when it retracts into the central bore inside the
stinger.
[0028] The
finger 160 has an undercut or notch 162 (zone of
reduced diameter) that engages a wire mesh segment of the
screen. Any
other suitable mechanism may be used to hook,
grip, attach or engage the screen. The
forward end of the
finger may have a bull-nose shape to push past a wire-mesh
segment of the screen. The forward and rearward walls of the
notch may be parallel to each other and have a square profile
as shown.
[0029] In
operation, the actuator extends to engage the wire
mesh segment of the screen by hooking the screen with the
undercut 162. The
actuator then partly retracts the screen
until the screen abuts the front face 101a of the stinger pad
101. The
retraction of the finger thus locks or clamps the
screen against the stinger pad. Once the
screen is snugly
abutted against the front face 101a of the stinger pad 101,
the screen can be handled or manipulated, e.g. translated
and/or rotated. Rotation of the screen is made possible by a
screen handler rotation motor 116.
[0mo] The cylinder retaining bracket 105 is mounted to a
front rotation motor adapter plate 115 by threaded fasteners
such as screws, e.g. hex head cap screws 119 with washers 114.
The screen handler rotation motor 116 is mounted between the
front adapter plate 115 and a rear rotation motor adapter
plate 117. The
motor 116 may be fastened to the front and
rear plates 115, 117 by threaded fasteners such as screws,
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e.g. hex head cap screws 121. A hose guide 120 may be mounted
to the rear plate 117 for guiding hydraulic hoses to the
actuator. The hose guide 120 may be mounted to the rear plate
117 by threaded fasteners such as screws, e.g. hex head cap
screws 126 and washers 114.
[00ai] The actuator assembly 150 may include an adjustment
mechanism. The
adjustment mechanism may include a friction
adjuster bolt 124 that threads into a screw thread insert
(e.g. a locking Heli-Coil insert) 123 and connects to a
friction brake bushing 122. By tightening the adjuster bolt,
the brake bushing 122 moves radially inwardly to increase the
frictional force exerted on the rotatable forward portion of
the screen-handling stinger. By loosening the adjuster bolt,
the brake bushing moves radially outwardly to reduce the
frictional force exerted on the rotatable forward portion of
the screen-handling stinger. The rotatable forward portion of
the stinger includes the pad 101, adapter plate 102, and
actuator 150. The adjuster bolt may have a knob for manual
adjustment or any head for adjustment using a wrench or
screwdriver or other tool. The adjustment mechanism enables
adjustment of the frictional coupling between the rotatable
forward portion of the screen-handling stinger and the rear
portion of the stinger (including housing 103). In other
words, the adjustment mechanism adjusts the frictional force
that frictionally couples the rotatable forward portion of the
screen-handling stinger (specifically the adapter plate 102)
to the rear portion (specifically outer housing 103 and
indirectly the retaining bracket 105 and front plate 115 which
are rotationally driven by the motor 116). In other
words,
the frictional coupling between components 102 and 103 is
adjustable. This adjustment exerts rotational resistance on
the rotation of the stinger so that it is selectively
rotatable. For example, the adjustment may be set so that the
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forward portion of the stinger (including the actuator)
rotates under a certain torque but not under other torque.
For example, it may be desirable to set the adjustment
mechanism to enable the forward portion of the stinger to
rotate independently relative to the rear portion when
indexing but to rotate the whole stinger (front and rear
portions coupled together) when picking up and manipulating a
screen.
[0032] METHOD OF INSTALLING A SCREEN
[0033] The
screen-handling stinger (or screen-handling system
or screen handler) that is disclosed herein also enables a
novel method of installing screening on a rock face in a mine.
[0034] This
novel method entails providing a screen-handling
stinger having a screen-handling actuator disposed within a
central bore of the stinger, extending the screen-handling
actuator relative to the stinger such that a screen-engaging
finger connected to a movable forward end of the actuator
hooks onto a screen, retracting the screen-handling actuator
until the screen abuts a stinger pad of the hydraulic stinger,
and bolting the screen to the rock face.
gmaq In one embodiment, the method further involves
rotating the screen. Rotating
may be accomplished using a
motor. The motor, in one embodiment, is affixed to a motor
adapter plate to which an actuator retaining bracket is
mounted. The actuator retaining bracket retains the screen-
handling actuator in this embodiment.
[0036] In one
embodiment, the method further involves wiping
the actuator using a wiper. In one specific embodiment, this
wiper may be disposed between a stinger pad and a guide
bushing. The
guide bushing may be disposed within a pivot
adapter plate (i.e. within a bore or inner diameter). The
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adapter plate may be mounted to the stinger pad in this
specific embodiment.
gmen In one embodiment, the method further involves
adjusting a frictional coupling between the adapter plate 102
and the outer housing 103. This may be accomplished using an
adjustment mechanism. This adjustment mechanism may have a
friction adjuster bolt that threads into a screw thread insert
and connects to a friction brake bushing.
[0038] ROCK BOLTING AND SCREEN INSTALLING SYSTEM
gmlq FIG. 6
is a side view of a rock bolting and screen
installing system (also referred to herein as a "rock
bolter"). This improved rock bolter, unlike conventional rock
bolters, includes a screen handler in the form of a modified
hydraulic stinger (i.e. a screen-handling stinger) having a
central bore in which is disposed a screen-handling actuator.
[0040] In
general, a rock bolter is designed to drill a hole
and then to install a rock bolt into the hole. For the
purposes of the present specification, the term "rock bolt" is
meant to encompass rebar, split sets, expandable bolts,
anchors or any other bolt-like elements designed to be
installed in a hole in a rock face to provide ground support.
[0041] With
reference to FIGS. 1-4, the rock bolter (or rock
bolting system), which is generally designated by reference
numeral 10, has a hydraulic stinger 20, a drill feed 30 and a
bolting feed 40. Each is
hydraulically actuated using a
hydraulic actuator (hydraulic cylinder, piston and rod). In
one specific embodiment, each of the stinger, drill feed and
bolting feed may be independently movable. In
operation, the
rock bolter is brought close to a rock face. A rock
face
means either the roof or the walls of a mine. Once the rock
bolter is properly positioned relative to the rock face, the
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rock bolter extends the stinger to sting the rock face.
Stinging the rock face means engaging or contacting the rock
face. Stinging is done to stabilize the rock bolter.
Therefore, stinging requires that the stinger press against
the rock face with sufficient force to stabilize the rock
bolter. With the stinger engaged against the rock face, the
rock bolter then extends the drill feed to drill a hole in the
rock. Once drilling is complete, the drill is withdrawn. The
finger is then extended by the screen-handling actuator from
the screen-handling stinger to engage a screen. The
actuator
retracts to pull the screen tightly against the pad. The rock
bolter then places the screen against a rock face by extending
and/or rotating the stinger and affixing the screen to the
rock face using one or more bolts.
[0042] As depicted in FIG. 6, the rock bolter 200 (rock
bolting and screen installing system) includes the screen-
handling stinger 100 and its forward bumper pad (stinger pad)
101. The rock bolter 200 includes a feed extension cylinder
228 and feed extension piston rod 229 for extending and
retracting the stinger 100.
g043] As further depicted in FIG. 6, the rock bolter 200
includes a mounting frame 212 for mounting the rock bolter to
a boom, platform, or other such structure. The rock
bolter
200 includes a carousel 214, a turret 216, and an indexing
mechanism 218.
[0044] The
drill feed 230 includes a rock drill 232 and drill
steel 33 that extends to the drill bit. The
drill bit is
advanced by the drill feed to drill the hole in the rock face.
After indexing using the indexing mechanism, the bolting feed
240 then drives a bolt 244 (having bolt tip 245) into the hole
that was drilled by the drill bit of the drill feed. The bolt
244 may include a bolt plate 246. The bolt plate 246 of the
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rock bolt is the end plate (flange, washer or head) of the
bolt that abuts the rock face when the rock bolt is inserted
into the hole. The rock
bolter may include a flexible
traveling bolt centralizer 300 and its sliding carriage 330
that is adapted to slid on the rails 242 of the bolting feed
of the rock bolter 200. The rock bolter may also include a
forward stationary bolt centralizer 350 that works with the
traveling centralizer to keep the bolt aligned with the hole.
[0045] This
screen handler or screen-handling stinger may be
an attachment that mountable to a distal and movable end of
any suitable feed to enable the stinger to grip and handle
screens. The
stinger itself may also extend and retract
relative to the rock bolter (and thus can translate or move
independently of the actuator inside the stinger). With the
rotational motor, the screen handler is able to both translate
and rotate the screen provided the screen is snugly clamped
against the stinger pad by the partly retracted finger. The
bolting feed may be used to insert a bolt into the rock face
to fasten the screen in place while the stinger is holding the
screen against the rock face.
[0m] FEED RAIL-MOUNTED SCREEN HANDLER
[0047] In another embodiment, the screen handler may be
mounted to a conventional feed rail or to a telescopic feed
rail as opposed to being mounted to, or incorporated within, a
hydraulic stinger. This feed rail may be either a drill feed
rail or a bolt feed rail. A rotation motor may be mounted
inside the feed rail (i.e. along an axis of the feed rail) or
outside of the feed rail (i.e. off-axis). For an
off-axis
motor, suitable gears, chain drive, belt drive or other power
transmission means are provided to transmit power from the
motor to rotate the screen handler.
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[0048] FIG. 7
and FIG. 8 show a feed-mounted screen handler
300 in accordance with another embodiment of the present
invention. The screen handler 300 is mounted to a drill feed
rail 310 in the illustrated example by a suitable mounting
bracket, flange or attachment 370. The
screen handler may
also be mounted to other types of feed rails. The
screen
handler has a cylindrical or circular bumper pad 301 (although
the pad may have any other suitable shape). The pad is 301 is
disposed at a forward end of the screen handler. An actuator
350 linearly displaces the finger 360 along an axis of
displacement that is substantially parallel to and aligned
with the feed rail although it may be off-axis in other
embodiments. The finger 360 of the actuator 350 extends from
a central bore (although the bore need not be aligned
centrally as shown). The finger is adapted (shaped and sized)
to engage a wire segment of the screen and to pull the screen
back against the pad 301 to thereby clamp or secure the screen
against the pad 301. The pad
301 is mounted to an adapter
plate 302 which is mounted to an outer housing 303 and an
actuator-retaining bracket 305. The
bracket 305 retains the
hydraulic actuator 350 that extends and retracts the finger
360.
[0049] This novel screen handler thus enables miners to
install protective screening on rock faces of mines. This
invention facilitates, and renders more efficient, the
installation of screening in a mine.
N050] The
present invention has been described in terms of
specific embodiments, examples, implementations and
configurations which are intended to be exemplary or
illustrative only. Other variants, modifications, refinements
and applications of this innovative technology will become
readily apparent to those of ordinary skill in the art who
have had the benefit of reading this disclosure. Such
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variants, modifications, refinements and applications fall
within the ambit and scope of the present invention.
Accordingly, the scope of the exclusive right sought by the
Applicant for the present invention is intended to be limited
solely by the appended claims and their legal equivalents.
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