U.S. patent number 3,827,754 [Application Number 05/321,337] was granted by the patent office on 1974-08-06 for low profile coal mining apparatus.
Invention is credited to Charles W. Gilley, deceased.
United States Patent |
3,827,754 |
Gilley, deceased |
August 6, 1974 |
LOW PROFILE COAL MINING APPARATUS
Abstract
Apparatus for mining shallow seams of coal or the like employs a
combination of parts resulting in a low profile of the machine and
which may be operated without requiring an operator to accompany
the machine to the mine face. The mining augers are remotely
controlled and may be adjusted to provide for mining of seams which
are thicker than the minimum profile height of the machine. The
augers are mounted on a carriage which travels along guides on a
base plate which can be shifted toward or from the mine face by
remote control, and the superstructure mounted on the carriage
reaches a height no greater than the diameter of the augers.
Inventors: |
Gilley, deceased; Charles W.
(late of Maury City, TN) |
Family
ID: |
23250183 |
Appl.
No.: |
05/321,337 |
Filed: |
January 5, 1973 |
Current U.S.
Class: |
299/30; 299/31;
299/57; 299/85.1 |
Current CPC
Class: |
E21C
29/16 (20130101); E21C 27/22 (20130101); E21C
35/24 (20130101) |
Current International
Class: |
E21C
35/00 (20060101); E21C 27/22 (20060101); E21C
29/00 (20060101); E21C 35/24 (20060101); E21C
27/00 (20060101); E21C 29/16 (20060101); E21c
027/24 (); E21c 029/16 () |
Field of
Search: |
;299/30,31,43,50,57,59 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Purser; Ernest R.
Attorney, Agent or Firm: Sherwood; William E.
Claims
What is claimed is:
1. Apparatus for mining coal or the like including, a base plate
having a low profile forward guide and a low profile rearward guide
affixed to the upper surface thereof, a low profile carriage
supported on said base plate and movable transversely thereof along
said guides, a pair of spaced augers projecting forwardly of said
base plate and mounted on said carriage with their axes parallel at
all times and directed toward the mine face normally to the path of
movement of said carriage, the rear portions of said augers being
at all times in advance of the forward edge of said base plate, low
profile motor means mounted on said carriage for driving said
augers and with its lowermost portion disposed adjacent said base
plate, means mounted on said carriage and coacting with said base
plate for moving said carriage transversely of said base plate, a
low profile orbital conveyor movable along said base plate beneath
said carriage rearwardly of said forward guide for moving material
dislodged by said augers and spilling over said forward guide,
means supported by said base plate for driving said conveyor, and
means for moving said apparatus selectively toward and from the
mine face.
2. Apparatus as defined in claim 1 wherein said means for moving
said carriage comprises a winch mounted on said carriage and
including cables attached at their ends to said base plate adjacent
the side edges of said base plate.
3. Apparatus as defined in claim 2 wherein said cables extend
adjacent the plane of said carriage and over the side reaches of
said orbital conveyor.
4. Apparatus as defined in claim 1 wherein the rearward guide is
shorter than the forward guide and is disposed to provide space for
movement of said orbital conveyor around its respective ends.
5. Apparatus as defined in claim 4 wherein said forward guide
serves as a confining wall along which the flights of said orbital
conveyor are moved.
6. Apparatus as defined in claim 4 wherein said guides comprise
L-shaped members with the respective upper legs thereof facing from
each other.
7. Apparatus as defined in claim 6 wherein said carriage includes a
plurality of rollers mounted thereon adjacent its forward edge and
movable in contact with the edge of the upper leg of said forward
guide.
8. Apparatus as defined in claim 6 wherein said carriage includes a
plurality of rollers mounted thereon adjacent its forward edge and
movable in contact with said base plate and beneath the upper leg
of said forward guide.
9. Apparatus as defined in claim 1 including an elevated and canted
shelf supported above the rear portion of said base plate and along
which said orbital conveyor is moved in its passage to and from its
movement along said base plate beneath said carriage.
10. Apparatus as defined in claim 9 including an opening in said
elevated shelf through which said orbital conveyor discharges its
contents.
11. Apparatus as defined in claim 10 including a bridge conveyor
having its forward end attached to said base plate and disposed
beneath said opening.
12. Apparatus as defined in claim 1 wherein said means for driving
said conveyor comprises a reversible motor driving a sprocket in
engagement with a chain of said conveyor and adapted to drive said
conveyor in either direction.
13. Apparatus as defined in claim 1 wherein said means for moving
said apparatus toward and from the mine face includes a skid plate
connected exclusively to said base plate by a plurality of
selectively extendible and retractable piston rods extending
horizontally from cylinders of fluid motors mounted on said skid
plate, and a plurality of roof plates connected to piston rods of
fluid motors mounted on said skid plate and adapted selectively to
be engaged and disengaged from the mine roof.
14. Apparatus for mining coal or the like including, a base plate,
a low profile carriage supported on said base plate and movable
transversely thereof, first and second spaced augers projecting
forwardly of said base plate and mounted on said carriage with
their axes parallel to the plane of said base plate at all times
and directed toward the mine face normally to the direction of
movement of said carriage, the respective augers having first and
second drive shafts, auger-pivoting means for selectively moving
said augers upwardly and downwardly, means mounted on said carriage
for actuating said auger-pivoting means, the rear portions of said
augers being at all times in advance of the forward edge of said
base plate, means mounted on said carriage for driving said augers,
means mounted on said carriage and coacting with said base plate
for moving said carriage transversely of said plate, a low profile
orbital conveyor movable along said base plate beneath said
carriage for moving material dislodged by said augers, means
supported on said base plate for driving said conveyor, and means
for moving said apparatus selectively toward and from the mine
face.
15. Apparatus as defined in claim 14 including a low profile
superstructure having uprights mounted on said carriage and
pivotally mounting a pair of interconnected spaced arms journalling
said first drive shaft and serving as the auger-pivoting means for
said first auger, and a double-acting fluid motor mounted on said
carriage and having a cylinder and piston rod connecting said
carriage to said interconnected arms.
16. Apparatus as defined in claim 14 including a superstructure
having uprights mounted on said carriage and supporting a pair of
coaxial separate shafts arranged parallel to said second drive
shaft a pair of interconnected spaced arms serving as the
auger-pivoting means for said second auger and mounted for pivotal
movement with one arm pivoting about one of said coaxial shafts and
the other arm pivoting about the other of said coaxial shafts, and
a double-acting fluid motor mounted on said carriage and having a
cylinder and piston rod connecting said carriage to said
interconnected arms.
17. Apparatus as defined in claim 16 wherein one of said arms
includes a bell crank portion having a lower end connected to the
cylinder and piston rod of said motor.
18. Apparatus as defined in claim 16 including a reversible fluid
pressure motor mounted on said carriage and including means for
driving one of said coaxial shafts independently of the other
coaxial shaft.
19. Apparatus as defined in claim 18 wherein said one of said
coaxial shafts comprises a winch drum and said means coacting with
said base plate comprises a pair of cables wound on said drum and
stretching adjacent the surface of said carriage to fixed abutments
respectively mounted at the side edges of said base plate.
20. Apparatus as defined in claim 19 including a pair of pulley
guides mounted adjacent the carriage plate beneath said winch drive
and around which the respective cables are passed.
21. Apparatus as defined in claim 16 wherein said auger-driving
means comprises a fluid pressure motor mounted centrally of said
carriage and driving a shaft provided with drive sprockets at each
end, one of said drive sprockets driving a first chain engaging
with a sprocket fixed to the shaft of one of said augers and the
other of said drive sprockets driving a chain engaging with a
sprocket fixed to one of said coaxial shafts, an auger-driving gear
fixed to the shaft of the other of said augers, and an idler gear
fixed to said chain-driven coaxial shaft and in mesh with said
auger-driving gear thereby to produce counter-rotation of the
augers.
22. A low profile remotely controlled apparatus for mining coal or
the like in low seams without requiring the presence of an operator
adjacent the mine face and including a base plate, a low profile
carriage supported on said base plate and movable transversely
thereof, a pair of spaced augers projecting forwardly of said base
plate and mounted on said carriage, the rear portions of said
augers being at all times in advance of the forward edge of said
base plate, a fluid pressure motor mounted on said carriage for
driving said augers, means including a winch driven by a reversible
fluid pressure motor mounted on said carriage and having cables
attached at their ends to said base plate for moving said carriage
transversely of said base plate, a low profile orbital conveyor
movable along said base plate beneath said carriage for moving
material dislodged by said augers, a fluid pressure motor supported
on said base plate for driving said conveyor, a skid plate having
roof plates disposed thereabove, a plurality of double-acting fluid
pressure cylinders having piston rods joining said base plate and
said skid plate and forming the exclusive means for varying the
spacing between said plates, a plurality of double-acting fluid
pressure cylinders having piston rods joining said skid plate and
the corresponding roof plates, a fluid pressure source located
externally of the mine and having conduits leading to and from the
respective motors, each of said motors having a solenoid operated
valve controlling the flow of fluid through the conduits connected
to the respective motor, and an electrical system operable from a
point remote from said base plate and having switches serving to
control the settings of the respective solenoids of said
valves.
23. An apparatus as defined in claim 22 including a bridge conveyor
connected at its forward end to said base plate and receiving
material discharged by said orbital conveyor, a fluid pressure
motor for driving said bridge conveyor and receiving fluid through
a conduit from said pressure source, a solenoid-operated valve
controlling flow of fluid to the bridge conveyor motor, and a
switch in said electrical system for controlling the setting of the
solenoid of the valve for the bridge conveyor motor.
24. An apparatus as defined in claim 22 wherein said electrical
system employs low voltage direct current and comprises the sole
usage of electricity required for operation of the apparatus within
the mine.
Description
BACKGROUND OF THE INVENTION
The present practice of auger mining of coal which does not require
an operator to crawl into the mine has obvious safety value, but
has other disadvantages such as the cummulative demand for power as
the auger length is extended, the periodic down-time as the auger
length is modified, and the amount of labor involved. Other types
of mining apparatus in which robot machines are employed, such for
example as the machines disclosed in the Alspaugh, et al., U.S.
Pat. Nos. 2,699,328 and 2,826,402, are relatively expensive and
complex, and in addition require considerable attention for
maintenance. Moreover, machines of this type are not well suited
for low seams, as illustrated by the definition in Alspaugh U.S.
Pat. No. 2,699,328 wherein the compact machine is stated to be 3
feet high.
As will be understood, mining of the so-called `low seams` of coal
or other materials has long presented problems to the designers of
mining machines and to operators of the same. Obviously, the
thinner the seam being mined the more cramped will be the space in
which an operator can accompany the apparatus during the mining
operation Accordingly, the need for remote control of the machine
increases with the dimunition of seam thickness while at the same
time the lower the profile of the apparatus the more limited is the
space available to the designer for the purpose of incorporating
the necessary machine elements and controls.
While the term `low seam` is comparative it will be understood that
a difference of not more than 1 inch of seam thickness may make all
of the difference between a given machine being usable or unusable.
Prior art patents often speak of machines for mining `low seams`
although a specified dimension may be lacking in their disclosures.
As will later appear in the present disclosure, however, the term
`low seam` is intended to signify a dimension of not more than 20
inches of seam thickness and indeed may be somewhat less.
This useful feature of the present invention derives essentially
from a novel combination of machine elements in which the conveying
apparatus, boring apparatus, power drives, and control apparatus
are all coordinated to obtain a low profile of the machine by the
cumulative effect of lowering the position of such elements to the
maximum practical extent. In addition, a conventional walking type
of machine is employed which may be operated as a robot from a
remote control point.
SUMMARY
The invention is embodied in a low profile dual-auger type of
mining apparatus having a base plate with transverse guides along
which a carriage is selectively moved. A low profile orbital
conveyor is driven by a motor supported on the base plate and
passes beneath the carriage. The carriage supports the augers in a
selectively pivoted position and includes motors for driving the
augers and for pivoting the same to the selected height on the mine
face. Remotely controlled means are provided for walking the
apparatus toward or from the mine face.
Among the objects of the invention are the provision of an improved
remotely controlled mining apparatus for use with low seams; the
provision of a low profile mining apparatus which may mine not only
low seams, but also seams of greater thickness; the provision of a
mining apparatus employing a hydraulic power system controlled by
low voltage solenoid valves; the provision of a low profile
carriage carrying dual augers and movable transversely of an
advancing base plate without requiring the presence of an operator
adjacent the base plate; and the provision of an improved conveying
means of low profile for removing material dislodged by a pair of
augers.
These and other objects and advantages of the invention will become
more apparent as the description proceeds and when considered in
conjunction with the accompanying drawings in which
FIG. 1 is a diagrammatic view indicating the nature of the cuts
which can be made in a seam of coal by the apparatus, the vertical
profile of the carriage being shown in dotted lines.
FIG. 2 is a plan view of the base plate and attached skid plate
with the carriage removed.
FIG. 3 is a side elevation of the structure of FIG. 2 with elements
omitted in the interest of clarity.
FIG. 4 is a plan view of the carriage and augers.
FIG. 5 is a sectional view to a larger scale taken on line 5--5 of
FIG. 4 and showing the carriage in operative position on the
forward guide.
FIG. 6 is a face view of the carriage supporting means of FIG.
5.
FIG. 7 is a sectional view taken on line 7--7 of FIG. 6.
FIG. 8 is a view of the carriage super structure taken on line 8--8
of FIG. 4 with parts in elevation and with parts omitted in the
interest of clarity.
FIG. 9 is a view to a larger scale as taken on line 9--9 of FIG. 4
and showing superstructure of the carriage plate.
FIG. 10 is an elevation view taken on line 10--10 of FIG. 4 and
showing superstructure of the carriage plate.
FIG. 11 is a view to a larger scale taken on line 11--11 of FIG. 2
and showing the mounting of the orbital conveyor drive
sprocket.
FIG. 12 is a diagrammatic view of the hydraulic drive system,
and
FIG. 13 is a wiring diagram for use in the robot control of the
apparatus.
A brief outline of the invention may be noted from consideration
initially of FIG. 1 indicating the general relationship of the
mining apparatus to the mine face 10 and showing its capability of
mining not only low seams, but also somewhat larger seams. As will
later appear, as the carriage plate 11 is moved along the guide 12,
affixed to the base plate 13, from its leftmost position to its
rightmost position, a complete cut equal in depth to the diameter
of each of the two augers is made, provided, however, that the axes
of the two augers are in the same plane. As will be noted, the
overall height D of the carriage assembly is somewhat less than the
diameter of the augers. When a cut is to be made in a seam thicker
than that made in a low seam, the righthand auger after making the
entry shown in solid lines at 14 is pivoted upwardly, while
rotating, into the dotted position 15, the lefthand auger meanwhile
still rotating in the solid line position 16. The carriage is then
moved to the right until the righthand auger occupies position 17
and the left hand auger fully overlaps the position 14. While still
rotating, the righthand auger is pivoted downwardly into position
18 and the left hand auger is pivoted upwardly into position 19
after which the carriage is moved to its leftmost position with the
lefthand auger being pivoted downwardly after it reaches position
20.
With the foregoing in mind, reference now is made to FIGS. 2 and 3
wherein the base plate 13 is shown with the forward guide 12 and
rearward guide 21 affixed thereto on its upper surface and spaced
from each other, the guide 21 being shorter and providing space for
an orbital conveyor to pass around its ends. The conveyor is
normally driven in the direction of the arrows and includes spaced
shallow flights 22 attached to an endless chain 23 engaged by idler
sprockets 25, 26, 27, 28 and 29 and by drive sprocket 24. Outer
walls 30, 31, 42 and 32 with arcuate walls 33 and 34 joining walls
30 and 31 respectively with the rear face portion 35 (FIG. 5) of
the forward guide 12 and with an arcuate wall 36 joining wall 32
with wall 42 provide a boundary along which the distal ends of the
flights will be moved and which confine the material being moved by
the conveyor.
As indicated in FIG. 11, the conveyor in its travel from adjacent
idler sprocket 26 to adjacent idler sprocket 25 moves in contact
with the base plate 13. However, its rearmost travel is along an
elevated and canted shelf 40 supported above that base plate and
joined at the left end to an intermediate inclined floor plate 41
having a wall 42 which joins walls 32 and 31. At the right end,
however, a shorter inclined floor plate 43 extends upwardly from
base plate 13 and an elevated opening 143 is provided between this
shorter plate and the canted shelf 40. Thus as the orbital conveyor
is moved it discharges its contents through that opening onto an
elongated bridge conveyor 46, later to be described.
Referring now to FIGS. 4 to 7, the generally rectangular flat
carriage plate 11 is provided at both its forward and rearward
edges with overhanging brackets 50, 51 respectively within which
are journalled the shafts of horizontally rotatable rollers 52
adapted to engage with the outwardly extending faces of the guides,
as seen in FIG. 5. A skirt 53 depending from the overhanging
bracket and spaced rearwardly of the beveled front edge 54 of the
base plate serves to mount the shafts of vertically rotating
rollers 55 which engage with the upper surface of the base plate.
These rollers support the weight of the carriage and the augers
carried thereby. Each end of skirt 53 is curved inwardly to
terminate adjacent the rear wall 35 of the guide thereby to shovel
the coal out of the path of the roller 55 as the carriage is
traversed to produce the mining action indicated in FIG. 1.
As will later be evident, as the augers move the broken coal (which
normally is of egg size or smaller) toward the carriage, such coal
spills over the top of forward guide 12 into the orbital conveyor
which is then moving under the carriage and behind guide 12.
Bracket 50 meanwhile is serving to divert the two streams of the
coal away from the rollers which mount the carriage on the base
plate. Significantly the described carriage mounting construction
enables the carriage plate 11 (which is required to carry certain
superstructure) to be located at the lowest practicable elevation
thus contributing to the low profile of the carriage and to the
mining of low seams.
A further important feature is noted on FIG. 8 wherein the carriage
plate 11 is provided with an aperture 60 into which the lower
portion 61 of the casing of the gear box of the auger driving motor
62 is mounted. This motor comprises a conventional rotary fluid
motor with gears serving to drive a shaft 63 having sprockets 64,
65 at its ends. In view of the power required for the auger drive
the gear box casing is of appreciable height and, unless lowered as
shown, would add to the profile of the mounted carriage. However,
sinking of the casing 61 to near the base plate 13 is made possible
since space is available between the rear guide 21 and the path of
travel of conveyor chain 23. Also shown on FIG. 8 is a portion of
the carriage superstructure including a pair of uprights 66, 67
affixed to the upper front surface of plate 11 and spaced from each
other to provide for pivotal movement of the forward arm 68 about
the pivot rod 69 and serving to adjust the working height of the
left auger 70. A similar pair of uprights 71, 72 mount a pivot rod
73 supporting a rearward arm 74 for that auger at the rear of plate
11. The distal ends of arms 68 and 74 are equipped with bearings in
which the auger shaft 75 is journalled and a member 76 is rigidly
attached to each arm and enables the assembly to pivot as a unit.
For pivoting the auger shaft 75 a double-acting fluid motor 80, as
seen in FIG. 10, employs a piston rod pivotally connected to a
bracket 77 affixed to arm 68 and a cylinder pivotally connected to
a lug 81 affixed to the upper surface of the carriage plate.
Intermediate its ends the auger shaft 75 has keyed thereto a
sprocket 82 driven by a chain 83 extending around the drive
sprocket of motor 62, the upper reach of this chain passing above
the member 76 and the lower reach thereof passing below that
member.
Extensions 84, 85 projecting from the front and rear uprights
provide for the mounting of a protective shroud (not shown) serving
to protect the apparatus from material which may fall from the roof
of the mine. As will be seen in FIG. 1 the top of these extensions
define the profile height D of the apparatus.
As shown in FIGS. 4 and 9, the shaft 89 of the righthand auger 90
is journalled in a combined bell crank and forward arm 91 and in a
rearward arm 92. At their distal ends, these arms are rigidly
joined by a member 94 which causes them to pivot as a unit. The
carriage plate has attached thereto a pair of spaced uprights 96,
97 in which a short shaft 98 is journalled for rotation and which
has an idler gear 99 attached thereto. This gear is constantly in
engagement with a gear 100 keyed to auger shaft 89 and which causes
that auger shaft to turn in a counter direction to the rotation of
the companion auger shaft 75. Also keyed to shaft 98 is a sprocket
101 over which a chain 102 is directed, this chain in turn being
driven by sprocket 64 associated with motor 62.
Additional spaced uprights 105, 106 and 107 rigidly attached to the
carriage plate provide a mounting for a winch shaft 109 coaxially
arranged with respect to shaft 98. A small shaft 110 mounted at its
ends in uprights 106 and 107 and having pulley guides 111, 112
suitably keyed thereto and located closely adjacent the carriage
plate is provided for the following purpose. As best shown in FIGS.
1 and 2, a first cable 115 is anchored at one end in an abutment
116 at the extreme left edge of the base plate 13 and a second
cable 117 is anchored at one end at the extreme right edge of that
base plate, the abutments having sufficient height to permit the
cables to be stretched above and close to the movable carriage
plate 11. These cables after passing the pulley guides are then
wrapped helically around winch shaft 109 in opposite directions and
have their innr ends rigidly affixed to that winch shaft whereupon
rotation of that shaft pays out one cable and rewinds the other.
Since the stretched cables lie close to the carriage plate, no
interference therewith can occur when the auger shafts are pivoted
downwardly as when a downwardly sloping cut by the augers may be
desired. Moreover, the resulting coaction of the base plate, the
carriage, and the cables together with the stepping of the
assembly, as later to be described, make it possible to conduct the
mining operation without requiring an operator to accompany the
machine into the mine.
For the purpose of rotating the winch shaft and thereby
reciprocating the carriage along the guides 12 and 21, a suitable
reversible fluid motor 120 and gear box are mounted on the carriage
plate. A sprocket 121 driven thereby in turn drives a chain 122
which engages with a sprocket 123 at the end of the winch shaft
109. A suitable shroud (not shown) encloses these sprockets and
chain and protects the same against coal being loaded into the
orbital conveyor.
Passing now to FIG. 10, a preferred arrangement for adjusting the
axis of the righthand auger 90 without increasing the profile
height D of the apparatus includes the mounting of the combined
bellcrank and arm 91 pivotally upon the winch shaft 109 between the
uprights 105 and 106. The shorter arm 130 of the bellcrank is
pivotable adjacent the carriage plate 11 and is pivotally connected
to the piston rod of a dual-acting fluid motor 131 the cylinder of
which is pivotally attached to an abutment 132 rigidly affixed to
the carriage plate. Actuation of this motor accordingly raises or
lowers the shaft 89 of the righthand auger.
Referring now to FIGS. 2 and 11, the intermediate inclined floor
plates 41, 43 and canted shelf 40 are supported by suitable braces
of which 140 and 141 are shown (FIG. 11). Adjacent the right rear
corner of base plate 13 a reversible fluid motor 142 is mounted
with a drive shaft inclined upwardly and carrying drive sprocket 24
engaging with chain 23 of the orbital conveyor. Adjacent this drive
sprocket the opening 143 in the orbital conveyor floor is located
and therebeneath the forward end of the bridge conveyor 46 is
suitably attached to the base plate 13. As will be understood, the
elongated bridge conveyor is driven at its rearward end as by means
of a suitable fluid motor 144 (FIG. 12) and as the base plate is
moved forwardly or rearwardly the bridge conveyor is simultaneously
shifted. In similar fashion the inclined floor plate 41 and the
shelf 40 are supported by braces at the left rear corner of the
base plate, and the idler sprocket 29 is mounted with its shaft
likewise inclined upwardly to engage with the chain of the orbital
conveyor. The height of the thus described assembly does not exceed
the dimension D.
For the purpose of advancing or retracting the base plate with its
attached bridge conveyor, a conventional stepping means is employed
comprising a skid plate 150 having a pair of abutments 151, 152 on
which a pair of parallel double-acting cylinders 153, 154 are
pivotally attached. Piston rods 155, 156 extending from the
cylinders are pivotally attached at their distal ends to abutments
157, 158 adjacent the rear edge of the base plate 13. The effective
length of extension of these rods from the cylinders is slightly
less than the distance to which the augers can be sumped into the
mine face.
Also mounted on the skid plate is a pair of spaced double-acting
vertically disposed cylinders 160, 161 having piston rods
projecting upwardly and pivotally attached to roof plates 162, 163
of substantial areas. Conveniently, an open end box housing 164 may
be located at the rear edge of the skid plate and the several fluid
pressure conduits serving the motors on the skid plate, base plate,
and carriage may be grouped within this housing (two such conduits
being indicated in FIG. 2) to avoid entanglement and to permit a
more effective movement of the mining apparatus.
Reference now is made to FIGS. 12 and 13 showing a suitable system
for operating the apparatus and indicating the comparative
simplicity of the control system. A pump 170, preferably of a
variable volume type, driven by a large motor 171 and located
externally of the mine draws fluid from a reservoir 172 and
supplies it to a first manifold conduit 173 leading into the mine
at a pressure of, for example, about 1,500-2,000 psi. A branch
conduit 174 controlled by a valve 175 leads to the motor 144 at the
rear of the bridge conveyor and disposed nearer the mouth of the
mine than the other motors of the apparatus. A second manifold
conduit 176 extends to the skid plate and has a third return
manifold conduit 177 leading to the reservoir 172 outside the mine.
Connected to the second and third manifold conduits are branch
conduits 179, 180 under control of valve 181 and communicating with
the respective ends of the left thrust cylinder 153. Likewise
connected to the second and third manifold conduits are branch
conduits 182, 183 under control of valve 184 and communicating with
the respective ends of the right thrust cylinder 154. Associated
with the respective valves 181 and 184 are conventional pressure
compensated flow control valves indicated generally at 178 and
178A.
Moreover, branch conduits 190, 191 under control of valve 192
communicate the second and third manifold conduits with the roof
jack motors 160, 161 through secondary manifold conduits 193, 194
thereby to effect simultaneous movement of these roof jack motors
under control of a single valve.
Also connected to the second and third manifold conduits are branch
conduits 195, 196 under control of a directional and pressure
compensated valve arrangement 197 and communicating with the
reversible motor 142 which drives the sprocket 24 for the orbital
conveyor. A fourth manifold conduit 200 extends to the carriage and
has a fifth return manifold conduit 201 leading to the reservoir
172 outside the mine. A branch conduit 203 under control of a
directional and pressure compensated valve arrangement 204 supplies
fluid to the auger-driving motor 62 and returns fluid therefrom to
the fifth manifold conduit 201 through branch conduit 205. Through
a branch conduit 210 fluid is supplied from the fourth manifold
conduit under control of a directional and pressure compensated
valve arrangement 211 to the winch motor 120 and is returned by
branch conduit 212 to the fifth return manifold conduit 201.
Likewise through a branch conduit 213 fluid is supplied from the
fourth manifold conduit under control of a directional and pressure
compensated valve arrangement 214 to the left auger-adjusting motor
80 and is returned by branch conduit 215 to manifold conduit 201.
In addition, through a branch conduit 216 fluid is supplied from
the branch conduit 200 under control of a directional and pressure
compensated valve arrangement 217 to the right auger-adjusting
motor 131 and is returned by branch conduit 218 to manifold conduit
201. Each of the valves 181, 184, 192, 214 and 217 may be the
conventional Vickers XM--DG4S4--012C--50 type defined as 4 way, 3
position, solenoid actuated, spring centered, closed center whereas
the valves 175, 197 and 211 for their respective motors may be
Vickers XM--DG4S4--0133C--50 type defined as 4 way, 3 position,
solenoid actuated, spring centered, motor spool.
For the more powerful auger motor 62 the valve 204 preferably is
the Vickers XM--DG5S4--0633--C--50 type defined as 4 way, 3
position, solenoid pilot actuated, spring centered, motor spool
type, and for the protection of the system a valve 220 which may be
the Vickers CG5--102A--C type defined as relief valve, solenoid
vented is provided and is adapted to vent into reservoir 172.
As shown in FIG. 13, a control panel 225 indicated by dotted lines
is provided for use by the operator in controlling the mining
operation. This normally is located outside the mine, although if
desired and feasible (as when seams of more than the defined `low`
height are being mined), it may be moved into the mine accompanied
by an operator. Since no electrical motors within the mine are to
be employed and since the only electrical energy required is for
operation of the solenoids of the valves, a relatively safe source
of low voltage current, for example 24 volts D.C., is supplied to
the control panel through conductors 226, 227.
METHOD OF OPERATION
The procedure to be followed in mining coal with the apparatus of
the invention may best be described as applied to surface entry
mining and involves at the beginning the provision of a ledge and a
sufficient opening into the seam to dispose within that seam the
base plate 13, and with a suitable temporary abutment being
provided for withstanding the forces generated at the beginning of
auger rotation. After starting the pump motor 171 outside the mine
the described fluid pressure system is filled with fluid, and the
initial cuts by the augers can be made and sufficient coal
excavated to provide room for the skid plate. The operator then
closes switch 230 (FIG. 13) in the proper direction to shift valve
192 and to cause the two roof jack motors 160, 161 to engage their
roof plates against the roof and to force skid plate 150 into tight
engagement with the mine floor thereby to provide a rigid abutment
inherent with the apparatus and against which auger-translating
forces may thereafter be applied. Next the switch 231 is closed in
the proper direction to shift valve 204 and to cause the auger
motor 62 to rotate and to drive the augers by means of chains 83
and 102. As will be understood, at this time the forward edge 54 of
the base plate is slightly outward of the vertical face of the seam
and the two augers are fully sumped into the seam. Thereafter, the
switch 232 is closed in the proper direction to shift valve 197 and
to cause the orbital conveyor motor to rotate and to drive the
sprocket 24 in engagement with chain 23 thus causing movement of
the orbital conveyor. Next switch 233 is closed in the proper
direction to shift valve 175 and to cause the motor 144 to drive
the bridge conveyor 46.
Then the switch 234 is closed in the proper direction to shift
valve 211 and to cause the winch motor 120 to turn in the direction
causing the carriage to move from left to right. Assuming now that
the diameter of the augers is twenty inches and that the point of
tangency of auger 70 is in the plane of the base plate 13 and
slightly to the left of that plate, and with the point of tangency
of the auger 90 in the same plane, the winch shaft upon rotation
will wind up the cable 117 and cause the right hand auger to be
moved to position 18 and the lefthand auger to be moved to position
14. A complete cut of 20 inches is then made and while the augers
are so being translated the dislodged coal is moved rearwardly and
spilled over the front guide 12 into the orbital conveyor which
like the bridge conveyor, is carrying away the coal. This
represents one alternative use of the apparatus as when the seam
thickness is equal to or only slightly greater than the diameter of
the augers. In this situation, after the carriage reaches its
righthandmost position switch 234 is restored to off position and
the winch motor comes to rest.
Then switch 230 is closed in the proper direction to cause valve
192 to shift and to retract the pistons in cylinders 160, 161 thus
disengaging the roof plates from the mine roof. Next switches 235
and 236 are closed in the proper direction to cause valves 181 and
184, respectively, to shift and to draw the cylinders 153, 154
toward the base plate. As will be understood, the weight of the
base plate which, for example, may be 12 feet in width, and the
weight of the carriage and its superstructure is far greater than
the weight of the skid plate and its attached parts. After skid
plate 150 is drawn to near the base plate, switch 230 is again
closed in the proper direction to cause valve 192 to shift and
again to clamp the skid plate to the mine floor and the roof plates
162, 163 to the roof. Thereafter, with the augers still rotating
and the orbital and bridge conveyors still travelling switches 235
and 236 are closed in the proper direction to cause valves 181, 184
respectively to shift and to extend the piston rods 155 and 156.
This action now causes the entire base plate 13 and the supported
carriage to move toward the mine face and as the base plate is so
moved it pulls forward the bridge conveyor. Any loose coal lying
between the mine face and the edge 54 of the base plate is cammed
up over the guide 12 and falls into the moving orbital conveyor and
as the assembly is so moved forwardly the two rotating augers are
sumped into the mine face in readiness for the next traverse of the
carriage. With the auger fully sumped into the seam the switch 234
is then closed in the proper direction to cause valve 211 to shift
and to cause the winch motor to rotate in the opposite direction.
As this occurs, the cable 115 is wound on the shaft 109 and the
carriage is moved from right to left with the left auger again
moving to position 16 and the right auger again moving to position
14. Thereafter the apparatus may be stepped forwardly as described
to initiate another cycle of operation.
When the mining has proceeded to the full extent of the power
provided by the hydraulic system, the several switches 231, 232,
233, 234, 237 and 238 are opened thus bringing their corresponding
motors to rest. Switches 213, 235 and 236 are then periodically
manipulated to walk the apparatus from the mine opening.
Although the apparatus is especially suited for mining low seams it
also is capable of mining thicker seams as shown in FIG. 1 and when
this is desired a different sequence of operation is followed.
Assuming that a seam of 30 inches is present and that the auger
diameter is 20 inches, the cycle would begin with the lefthand
auger sumped into the thick seam at position 16 (FIG. 1). The
switch 237 would then be closed in the proper direction to cause
valve 217 to shift and to cause fluid to be supplied to motor 131
in such way as to extend the piston rod thereof. Extension of this
rod acting in the bell crank leg 130 pivots the auger-supporting
arm 91 upwardly and brings the rotating auger 90 into position 15
in the coal seam. Switch 234 is then closed in the proper direction
as above described and the winch motor then moves the carriage to
the right until the righthand auger reaches position 17 and the
lefthand auger reaches position 14. Then with the augers still
rotating and the winch at rest, switch 237 is closed in the proper
direction to shift valve 217 and to retract the piston in the
cylinder of motor 131 whereupon the auger 90 pivots downwardly to
position 18 making an arcuate cut RC in the seam during this
movement. With the carriage still disposed at its extreme righthand
position, switch 238 is then closed in the proper direction to
shift valve 214 and to extend the piston rod in the cylinder of
motor 80 whereupon the auger 70 pivots upwardly to position 19.
Switch 234 is then closed in the proper direction to shift valve
211 and to actuate the winch motor which then moves the carriage to
the left. During this movement the auger 90 cuts the coal in the
seam between positions 18 and 14 and the auger 70 cuts the coal
between positions 19 and 20. When the carriage reaches its leftmost
position, switch 238 is then closed in the proper direction to
shift valve 214 and to retract the piston rod in the cylinder of
motor 80 whereupon the auger 70 pivots downwardly to position 16
making an arcuate cut LC in the seam during this movement.
As shown by FIGS. 12 and 13, closing of an emergency switch 240 at
any time serves to vent the pressure fluid system and to bring the
mining apparatus to a halt.
Having generally described the normal mining operation it will be
apparent to those skilled in the art that the apparatus possesses
valuable capabilities not yet described. For example, in the event
that an object falls from the mine roof and acts to clog movement
of the orbital conveyor in its passage beneath the carriage plate
it is a simple matter to shift switch 232 so as to shift valve 197
in the proper direction to reverse the rotation of motor 142. The
orbital conveyor can travel in either direction although its
flights propel the coal more efficiently in the clockwise direction
of FIG. 2. However, when motor 142 is reversed the drive sprocket
24 turns in a reverse direction and the conveyor can carry the
obstructing object to the opening 143.
Frequently, the seam being mined will be found to slope upwardly or
downwardly from a horizontal plane. The mounting of the dual auger
shafts in arms which may be selectively pivoted upwardly or
downwardly permits the apparatus to be accomodated to sloping
seams. As will be understood, the normal position of the pistons in
the cylinders of motors 80 and 131 thus will be located
intermediate the ends of those cylinders.
The arrangement of the various elements of the apparatus is
coordinated to effect a compact and relatively simple machine of
low profile and which is well suited for use as a robot controlled
from the exterior of the mine. Any suitable means for sensing the
several phases of operation and for communicating the necessary
information to the operator at a remote point may be employed, and
as such forms no part of the present invention.
As will be apparent, after the apparatus is installed in a mine
opening a single operator can control the operation from the
control panel 225. The bridge conveyor 46 can be of indeterminate
length and by means of conventional gearing one section of conveyor
can be attached to another in order to lengthen the same, the
lengthened conveyor still being driven by the single motor 144.
The conduits supplying pressure fluid to the motors as well as the
electrical conductors leading to the solenoid valves associated
with those motors may readily be bundled and pulled forwardly as
the apparatus is stepped into the mine; these conduits and
conductors being spaced from the bridge conveyor and being
withdrawn from the mine from a station outside the mine when the
apparatus is stepped from the mine.
As will be understood, other means for quickly withdrawing the
apparatus from the mine without relying upon the step-by-step
retraction may be employed without departing from the invention.
For example, cables (not shown) attached to the apparatus and
extending to a winch located outside the mine could be
employed.
Moreover, if an operator should accompany the apparatus into the
mine he is not required to occupy a position close to the base
plate where the likelihood of roof falls is greatest. Rather he may
move forwardly well behind the augers and take conventional
precautions, such as installing roof support plates, as he moves
forwardly thus to insure his safety under supported roof
conditions.
The apparatus is of a size making it economically feasible to mine
low seams and, as an example, a cut in excess of 12 feet in width
and to a depth of several hundred feet into the seam may be made
before the apparatus has to be withdrawn for making a similar cut
from the same seam. Furthermore, in contrast with conventional
auger mining much less labor is required for the production of a
given quantity of coal.
Having disclosed a preferred form of mining apparatus, it will be
understood that the invention may be embodied in other forms than
that described as the preferred form, and without departing from
the scope of the appended claims.
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