Note: Descriptions are shown in the official language in which they were submitted.
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Method and Device for Mining Underground Deposits
The invention relates to a method for mining underground
deposits using a mining machine, wherein an upper and a lower
drift are driven, which extend on both sides of the deposit to
be mined, and a preliminary bore is sunk between the two
drifts, as well as a device for carrying out said method.
For mining underground deposits, machine types have been
developed, which in most cases are displaceable along haulage
means parallelly with the seam or deposit. Depending on the
mightiness of the seam, different configurations have become
known, which, as a rule, are fixed in the drift by the aid of
chains or wire rope hoists. From DE-OS 38 09 768, a method for
mining underground deposits has, for instance, become known, in
which a preliminary bore is sunk between the two initially
driven tracks and a milling procedure using contradirectional
milling rolls, is performed by the aid of a chain or wire rope
hoist from the lower driven track to the upper driven track.
Due to the steepness of the drift, the exposed or excavated
material can each fall down onto a conveying means provided in
a driven track.
Another method for mining underground deposits is described in
AT 410 001 B. Prior to the beginning of the mining process, two
galleries are again initially driven on different levels, with
the seam extending in the region between those two galleries.
After this, a first connection gallery is driven along the seam
corresponding to the seam thickness, to which end
conventionally designed driving machines or even explosive
drilling methods may be employed. In the upper of the two
driven galleries, a ramp is formed to support a cable winch so
as to enable a mining machine mining the material starting from
the first connection gallery to emerge from the seam and be
again maneuvered back into the extraction region in an
accordingly offset manner. The mining machine employed is, for
instance, designed as a so-called "narrow reef miner", which
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renders feasible the efficient and economic mining of
particularly low seams using the undercutting principle and
which also enables the extraction of hard material in the
course of the seam track. The undercutting tools used in such
mining machines, in particular with hard material, allow for an
increased cutting performance due to a substantially higher
portion of broken material, wherein such tools working
according to the undercutting principle, due to the lumpy parts
excavated, enable tunnel driving and mining not only more
rapidly and more efficiently, but also with a substantially
reduced dust development. With the mining machine known from AT
411 481 B, layer by layer is radially removed from the.interior
outwards in an undercutting manner by tools fastened to a
rotationally driven drill head.
In accordance with the invention, the previously described
mining methods are to be improved to the effect that, departing
from a preliminary bore between an upper and a lower drift,
also the mining of very steeply extending deposits will be
feasible in a simple manner, whereby, in particular, also the
extraction of material in nearly perpendicularly extending
seams is to be feasible while, at the same time, ensuring the
safe positioning of the mining machine.
To solve this object, the method according to the invention is
characterized in that a supporting device is fixed at the mouth
of the preliminary bore in the upper drift, that a mining
machine supported on the supporting device is positioned at the
mouth of the preliminary bore so as to be oriented in the
longitudinal direction of the preliminary bore, and that the
mining machine is advanced from the upper drift to the lower
drift corresponding to the course of the preliminary bore. By
arranging a supporting device in the upper drift at the mouth
of the preliminary bore, the prerequisite is provided for the
positioning of the mining machine in the upper drift prior to
the start of the break-in procedure and prior to the immersion
into the seam, corresponding to the inclination of the course
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of the seam, so as to enable the mining machine to be arranged
and supported at any angle of inclination while, in particular,
enabling inclinations of up to 90 , such that even the mining of
very steeply located seams will be feasible directly from the
upper drift. In this case, the advance of the mining machine is
effected from the supporting device in the direction of the
preliminary bore from the upper drift to the lower drift. The
method according to the invention, thus, merely requires to
initially sink a preliminary bore between the upper and the
lower drift, with the extraction by the mining machine being
already feasible immediately thereupon.
When the mining machine has reached the lower drift, it is
provided according to a preferred mode of operation that the
mining machine is pulled back to the upper drift by the aid of
a wire rope hoist. The mining machine is, thus, able to
completely emerge from the seam and be again supported on the
supporting device. After this, the supporting device can be
moved in the upper drift to the next mining position desired so
as to enable the mining machine to be maneuvered back into the
mining region in an accordingly offset manner.
For the haulage of the extracted material, no separate haulage
device is necessary in the mining region according to a
preferred mode of operation, but it is provided that the
extracted material is removed towards the preliminary bore, or
in the direction of the already excavated region, by the aid of
a clearing tool provided on the mining machine so as to cause
the extracted material to fall down through the preliminary
bore, or the already excavated region, and reach a haulage
device arranged in the lower drift. The material broken loose
will, thus, fall into the lower drift by its own weight as soon
as it is moved into the preliminary bore by appropriate
clearing tools. The removal of the extracted material may
advantageously take place during the mining procedure such that
material is excavated and the extracted material is removed and
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hauled in a single operation. Hence results an extremely
efficient and time-saving mode of operation.
According to a preferred mode of operation, it is proceeded in
a manner that material is excavated using disc or roller tools
operating on the undercutting principle, thus ensuring a
particularly efficient and economic mode of 'operation as
already pointed out in the beginning.
In order to ensure the safe support of the mining machine in
the upper drift even with very steep and, in particular, nearly
perpendicular seams, it is preferably proceeded in a manner
that the mining machine is braced within the supporting device
designed as a frame-shaped structure by means of extractable
props. Such a frame-shaped support structure is, thus, fixed at
the mouth of the preliminary bore in the upper drift and, for
instance, delimits an interior space whose dimensions in the
vertical direction of the mining machine approximately
correspond to the thickness of the seam to be worked on. Within
the space defined by the frame-shaped support structure, the
mining machine can be braced by the aid of the extractable
props so as to enable an accordingly precise and safe
positioning of the mining machine even at a very steep course
of the seam. The frame-shaped support structure in this case
must be positioned in the upper drift in such a manner as to
enable the mining machine braced within the frame-shaped
support structure to be arranged corresponding to the
inclination of the course of the seam.
The device for carrying out the method according to the
invention is characterized by a mining machine as well as a
supporting device for supporting the mining machine in the
upper drift in the region of the mouth in a position oriented
in the longitudinal direction of the preliminary bore. As
already mentioned, the supporting device may be designed as a
frame-shaped structure within which the mining machine is
braceable by the aid of extractable props. To return the mining
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machine after having reached the lower drift, the mining
machine is preferably fastened to the supporting device by the
aid of a carrying device, said carrying device advantageously
being comprised of a chain hoist or a wire rope hoist. The
5 supporting device in this case is, for instance, provided with
a cable winch, by which the mining machine can be pulled back.
As already mentioned, a mining machine operating on the
undercutting principle is preferably arranged, to which end the
configuration is advantageously further developed such that the
mining machine carries disc or roller tools rotationally
mounted on a pivotable cantilever arm and operating on the
undercutting principle. In this respect, a configuration
according to AT 411 481 B may, for instance, be chosen, and it
is, therefore, preferably provided that the disc or roller
tools are fixed to a head drivable for rotation, whose axis of
rotation extends substantially in the direction of the axis of
the cantilever arm, said axis of rotation of the head carrying
the tools being mounted on the machine frame so as to be
pivotable about an axis crossing the axis of the cantilever arm
and extending upstream of the pivot axis of the cantilever arm
arranged transversely to the driving direction, viewed in the
driving direction. Further improvement results from a preferred
further development, according to which the pivot bearing of
the cantilever arm is arranged on a carriage displaceable in
the longitudinal direction of the machine frame. Such a
configuration allows the mining machine to remain braced within
the frame-shaped support structure at the beginning of the
break-in procedure and at the beginning of the immersion into
the seam, since it will do to advance the carriage along with
the disc or roller tools in the longitudinal direction of the
machine relative to the machine frame while thereby driving the
disc or roller tools into the seam. The support of the mining
machine within the support frame can, thus, be maintained at
the beginning of the break-in procedure so as to enable the
occurring forces to be taken up by the support structure via
the extractable props. It is only when the maximum advance of
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the carriage has been reached that the machine will have to be
reset. In order to achieve as stable a positioning of the
mining machine as possible within the machine frame and the
seam, respectively, the configuration is preferably further
developed in a manner that the machine frame is braceable
between the floor and the roof via a plurality of props,
wherein props are arranged on both sides of the longitudinal
central plane of the machine frame, and that at least one
further prop is arranged on the carriage in the region of the
pivot axis of the pivoting mechanism so as to be adjustable
relative to the roof and the.floor.
In order to ensure the haulage of the extracted material
simultaneously with the excavation of the material, the
configuration is advantageously devised such that the
cantilever arm carries clearing tools, preferably clearing
shields, for removing the excavated material in the direction
of the preliminary bore. Thereby, the removal of the extracted
material is simultaneously effected at a pivotal movement of
the cantilever arm carrying the cutting tools, wherein the
cantilever arm is pivoted in the direction towards the
preliminary bore such that the excavated material will fall
down via the preliminary bore onto the lower drift, from where
it can be transported off by a separate haulage device.
In the following, the invention will be explained in more
detail by way of an exemplary embodiment schematically
illustrated in the drawing. Therein, Fig. 1 is a schematic
illustration of the mining method by which an inclinedly
extending seam is mined between two drifts driven on different
levels; Fig. 2 is an enlarged illustration of the upper drift;
Fig. 3 is a view of the upper drift along arrow III of Fig. 2
at the beginning of the mining operation; and Fig. 4 is an
illustration corresponding to Fig. 3 with the mining operation
being further advanced.
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From Fig. 1 it is apparent that, prior to the beginning of the
mining operation, two drifts, namely an upper drift 1 and a
lower drift 2, are initially driven on different levels, with
the seam extending in the region between these two drifts 1 and
2. Subsequently, a preliminary bore 3 is formed along the seam,
wherein the inclination a of the preliminary bore 3 between the
upper and lower drifts may be up to 90 . Fig. 2, on an enlarged
scale, depicts the upper drift 1, which is joined by the
preliminary bore 3. In the region of this juncture or mouth, a
supporting device 4 is provided, which is designed as a frame-
like structure. The frame-like structure 4 is inclined in
accordance with the longitudinal direction of the preliminary
bore. At the beginning of the mining operation, the mining
machine 5 is braced within the supporting frame 4 by the aid of
props 6 such that the mining machine 5 will likewise be
arranged in accordance with the inclination of the preliminary
bore 3.
Fig. 3 is a top view on the mining machine 5, from which it is
apparent that props 6 are arranged on both sides of the
longitudinal axis of the machine. On the front end of the
machine 5 is arranged a cantilever arm 7 whose rotating head 8
carries disc or roller tools. The cantilever arm 7 is fixed to
the machine frame, or a carriage displaceable relative to the
machine frame, so as to be pivotable about a pivot axis 9, the
pivot drive being formed by hydraulic cylinder piston units 10.
By pivoting the cantilever arm 7, a region 11 adjoining the
preliminary bore 3 is exposed, wherein, at a pivotal movement,
the extracted material is removed towards the preliminary bore
3 by clearing tools fixed to the cantilever arm 7, falling down
to the lower drift 2 through said bore. While the mining
machine 5 in the illustration according to Fig. 3 is still
braced in the frame-like support structure 4 by the aid of the
props 10, Fig. 4 depicts a further advanced position of the
mining machine 5, in which the machine is braced against the
roof and the floor within the seam.
