Note: Descriptions are shown in the official language in which they were submitted.
WO 2022/139663
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DRILL BIT CHANGE IN FACE DRILL RIG
TECHNICAL FIELD
This invention relates to automatic drill bit change typically in
face drill rigs and, in particular, to a drill bit change positioner, a
drill bit feeder, a drill bit magazine, implementation in a drill rig,
a drill bit changer, and a method for drill bit change.
BACKGROUND AND RELATED ART
To maintain the function of a drill bit when drilling in rock, that
is, not to lose sharpness of the drill bit, the drill bit should be
replaced before it is worn out.
Today, when a drill bit is to be replaced, an operator may step
out of the drilling rig to change the drill bit manually. Drilling is
then halted and the operator will be in a position exposed to
machinery and hazards of the environment, such as falling rock
and slippery surfaces. Automatic or semi-automatic drill bit
changers have been proposed, but the drill bit changer solutions
seen to date appear to be technically overly complicated, to be
exposed to risk of collision with machinery or the rock
environment, to lack durability, as indicated above to demand
extensive interaction by a human operator, or to be inefficient in
terms of cost and running time lost in the drill bit change
operation.
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Drill bit wear characteristics vary depending on the type of rock
to be drilled and the type of drilling machine. When drilling for
the constructing of tunnels, a large amount of drill bit changes
need to be performed. Thus, significant time saving and other
advantages in relation the above-mentioned problems could be
gained therein.
Drill bit changing components or solutions in the general field of
rock drilling have been proposed in documents GB 1 357 715,
SE 378 877 B, WO 2009/156574 Al, WO 2009/156575 Al, and
EP 3 415 709 Al. None of these seems to provide solutions or
fully satisfactory solutions to the above-mentioned problems.
SUMMARY OF INVENTION
Generally, the invention solves or alleviates problems indicated
above. This is done by providing drill bit change, in which the
operator does not have to get out of the rig to change drill bits.
The operator can thus continue drilling with other drill beams of
the rig at the same time as the drill bit change takes place. The
risky working environment for the operator in front of the rig
vehicle when changing drill bits is avoided. The inventive drill bit
changer can be designed to be loaded with as many drill bits as
required for completing all drilling required in an entire face in
tunnel construction, from the drill rig's approach to the face to
its withdrawal from the face (for instance in drill and blast tunnel
construction). A human operator will not need to get out of a
protective operator compartment of the drill rig.
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A very slim design of the components and their mounting
alongside and in parallel to the feed beam are important aspects
of the invention and provides advantages by keeping the
components from physical exposure to the surroundings and to
other parts of the drill rig itself. The components all being
located behind or preferably well behind the front end of the
feed beam (except in a longitudinally protruding position for
interacting with the drill rod) also advantageously keeps the
components further out of physical exposure.
Although the invention is mainly directed towards a complete
solution for drill bit exchange in face drill rigs, components and
sub-methods included therein interact via distinct interfaces,
which motivates the invention also being defined through its
components and sub-methods alternatively to the combination
thereof. Particularly, the invention involves the following.
A drill bit change positioner movably mounted on a feed beam
configured to be part of a drill rig for rock drilling, said drill bit
change positioner movably mounted on the feed beam
comprising: the feed beam having a drill rod support bearing at
a front end configured to be turned towards a rock to be drilled,
a drilling machine at a rear end opposite to the front end , and a
longitudinal axis extending between the front end and the rear
end; the drill rod support bearing having a drilling machine side
and a drill bit side opposite thereto; a drill bit holder having a
drill bit holder axis and being configured to hold a drill bit
aligned with the drill bit holder axis; a positioner arm coupled, at
a first end thereof, to the drill bit holder; a longitudinal
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movement mechanism having a longitudinal movement axis
oriented alongside the feed beam parallel to the longitudinal
axis; the longitudinal movement mechanism being coupled to a
second end of the positioner arm distally of the first end
thereof; the longitudinal movement mechanism being configured
to move the drill bit holder by the positioner arm between a
retracted longitudinal position , in which the drill bit holder is at
least partly longitudinally retracted behind the drill bit side in a
direction from the front end towards the rear end, and a
protruded longitudinal position, in which the drill bit holder
protrudes longitudinally in its entirety in front of the drill bit side
in a direction from the rear end towards the front end; a
transverse movement mechanism coupled to the positioner arm
and being configured to move the drill bit holder transversally to
the longitudinal axis between a drill bit feeder position, in which
the drill bit holder is configured to interact with a drill bit feeder,
and a drill rod position, in which the drill bit holder is configured
to align longitudinally with the drill rod support bearing.
The compactness of the inventive drill bit changer is an
advantage along with a high capacity of holding new drill bits to
be used (possible along a large part of the length of side of the
feed beam, depending on numeral requirement). This leads to
the most significant benefit of the invention, which is protecting
human operators by removing the need for manual involvement
at the feed beam in the drill bit change process while at the face
to be drilled. In terms of realizing advantages of the invention,
reference is made also to a combination with a drill bit feeder
and a drill bit magazine.
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Optionally, the drill bit change positioner comprises the
longitudinal movement mechanism and the transverse
movement mechanism being integrated in a single drill bit holder
5 movement mechanism.
Optionally, the drill bit change positioner comprises the
transverse movement mechanism being configured to provide
the transverse movement of the drill bit holder around a
rotational movement axis aligned the longitudinal movement
axis.
Optionally, the drill bit change positioner comprises the
longitudinal movement axis and the drill bit feeder position being
located at opposing sides of the feed beam.
The drill bit change positioner makes efficient use of space that
may be available on a side of and underneath the feed beam,
with just a flat metal structure when retracted fitting very snugly
with the bottom of the feed beam. This structure reaches with its
drill bit holder to the opposite side of the feed beam, where it is
exchange used drill bits for new drill bits. The drill bit change
positioner has a small "footprint" at and around the feed beam
and it occupies a small volume only.
The invention further involves a drill bit feeder mounted on a
feed beam configured to be part of a drill rig for rock drilling,
said drill bit feeder mounted on the feed beam comprising: the
feed beam having a drill rod support bearing at a front end
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configured to be turned towards a rock to be drilled, a drilling
machine at a rear end opposite to the front end , and a
longitudinal axis extending between the front end and the rear
end; the drill rod support bearing having a drilling machine side
and a drill bit side opposite thereto; a drill bit gripper configured
to grip and release on one side of the feed beam a drill bit in a
drill bit holder of a drill bit change positioner, in locations
longitudinally behind the drill bit side in a direction from the front
end towards the rear end.
Optionally, the drill bit feeder comprises the drill bit change
positioner according to the above, wherein the drill bit feeder
position is on said one side of the feed beam.
The invention further involves a drill bit magazine mounted on a
feed beam configured to be part of a drill rig for rock drilling,
said drill bit magazine mounted on the feed beam comprising:
the feed beam having a drill rod support bearing at a front end
configured to be turned towards a rock to be drilled, a drilling
machine at a rear end opposite to the front end, and a
longitudinal axis extending between the front end and the rear
end; the drill rod support bearing having a drilling machine side
and a drill bit side opposite thereto; the drill bit magazine being
configured to hold a plurality of drill bits inside the drill bit
magazine and to feed on one side of the feed beam a drill bit to
a drill bit holder of a drill bit change positioner via locations
longitudinally behind the drill bit side in a direction from the front
end towards the rear end; the drill bit magazine being configured
to hold the plurality of drill bits parallel to the longitudinal axis;
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the drill bit magazine being configured to convey the plurality of
drill bits towards a drill bit feeder position.
Optionally, the drill bit magazine comprises a carrier mechanism
configured to mode the plurality of drill bits parallel to the
longitudinal axis.
Optionally, the drill bit magazine comprises the drill bit change
positioner and the drill bit holder according to the above.
The invention further involves a rock-drilling drill rig carrying, on
at least one drill boom thereof, the feed beam and at least one
of: the drill bit change positioner according to the above; the
drill bit feeder according to the above; the drill bit magazine
according to the above.
Further, the invention is a drill bit changer mounted on a feed
beam configured to be part of a drill rig for rock-drilling, said
drill bit changer mounted on the feed beam, comprising a drill bit
change positioner movably mounted on the feed beam according
to the above; a drill bit feeder mounted on the feed beam
according to the above, and, optionally, a drill bit magazine
mounted on a feed beam according to the above.
The method or sub-method aspects of the invention disclosed
herein constitute substantial contributions over the prior art, for
instance, in that a robust process for drill bit change.
BRIEF DESCRIPTION OF DRAWINGS
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Fig. 1 shows a drill rig for rock drilling, here in an underground
rock tunnel environment, equipped two feed beams each having
a drill bit changer (not shown explicitly), according to the
invention.
Fig. 2 shows a top-front-right-side perspective view of a front
end of one feed beam having a drill bit changer mounted thereto
and is further intended to be explanatory of an operational
principle of a combined longitudinal and transverse movement
mechanism of a drill bit change positioner, according to the
invention.
Fig. 3 shows a right side planar view of a front end of one feed
beam having a drill bit changer mounted thereto and is further
intended to be explanatory of an operational principle of a
combined longitudinal and transverse movement mechanism of
a drill bit change positioner, according to the invention, wherein
a drill bit holder thereof is in its longitudinally retracted position.
Fig. 4 shows a right side planar view of a front end of one feed
beam having a drill bit changer mounted thereto and is further
intended to be explanatory of an operational principle of a
combined longitudinal and transverse movement mechanism of
a drill bit change positioner, according to the invention, wherein
a drill bit holder thereof is in its longitudinally protruding
position.
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Fig. 5 shows a front view of a front end of one feed beam having
a drill bit changer mounted thereto, according to the invention,
wherein the drill bit changer is in a retracted longitudinal
position in which a new drill bit is to be received from a drill bit
feeder or a used drill bit is to be released to a drill bit feeder.
Fig. 6 shows a front view of a front end of one feed beam having
a drill bit changer mounted thereto, according to the invention,
wherein the drill bit changer is in a protruding longitudinal
position in which a drill bit is to be threaded onto or off from a
drill rod.
Fig. 7 shows a top-front-left-side perspective view of a front end
of one feed beam having a drill bit changer mounted thereto and
is further intended to be explanatory of an operational principle
of a drill bit change positioner, a drill bit feeder and a drill bit
magazine, according to the invention.
Figs. 8a and 8b show a planar side view of a drill bit feeder to
be mounted on a side of a feed beam in a releasing
configuration and a gripping configuration, respectively, and is
further meant to indicate an operational principle, according to
the invention.
Figs. 9a ¨ 9i show in planar cross-sectional side views a
combination of a drill bit feeder and a drill bit magazine to be
mounted on a side of a feed beam in different operational
configurations for conveying a new drill bit to a drill bit feeder
position and conveying a used drill bit from the drill bit feeder
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position to an ejection opening and is further meant to indicate
an operational principle, according to the invention.
Fig. 10 is a flow chart of a method of operating a drill bit change
5 positioner in a context of a rock-drilling drill rig, wherein a used
drill bit is removed from the drill rod.
Fig. 11 is a flow chart of a method of operating a drill bit change
positioner in a context of a rock-drilling drill rig, wherein a new
10 drill bit is provided to the drill rod.
Fig. 12 is a flow chart of a method of operating a drill bit
changer in a context of a rock-drilling drill rig, wherein the drill
bit changer has a drill bit feeder and a drill bit magazine, which
interact with the drill bit change positioner.
In summary, disclosed herein is an automatic drill bit changer on
a feed beam configured to be part of a drill rig for rock-drilling,
wherein the drill bit changer is elongate and mounted along
opposed first and second sides of the feed beam. The drill bit
changer has a drill bit change positioner movably on the first
side and reaching by a positioner arm underneath the feed beam
to the second side and a combination of a drill bit feeder and a
drill bit magazine mounted on the second side of the feed beam.
The drill bit change positioner is capable of swinging with a
single longitudinal and rotational movement axis from a drill bit
feeder position on the second side to a protruded position at
which it interacts with a drill rod to change drill bits. A drill rig so
equipped and related method aspects are disclosed.
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DETAILED EMBODIMENT DESCRIPTION
The figures illustrate an embodiment of the invention. Fig. 1
shows a face drill rig 1 about to drill into a face of a rock in an
underground tunnel. The rig 1 carries has two booms 2, 3 each
having a feed beam 4, 5 that carries a drill bit changer 6.
As shown in figs. 2 ¨ 9, each drill bit changer has three main
components: a drill bit change positioner 7, a drill bit feeder 8,
and a drill bit magazine 9 mounted at a front end 10 of the feed
beam 4.
Figs. 2 and 3 show a right side of the front end 10 and part of
the drill bit change positioner 7 mounted movably to the feed
beam 4. The drill bit change positioner 7 has a positioner arm 11
that extends underneath the feed beam 4 to an opposite side
(left side in this context) where it carries drill bit holder 12 in a
drill bit feeder position.
The drill bit change positioner 7 is movably mounted on a feed
beam 4 configured to be part of the drill rig 1 for rock drilling.
The drill bit change positioner 7 movably mounted on the feed
beam 4 and comprises: the feed beam 4 having a drill rod
support bearing 13 at the front end 10 configured to be turned
towards a rock to be drilled, a drilling machine 14 at a rear end
15 opposite to the front end 10, and a longitudinal axis 16
extending between the front end 10 and the rear end 15; the drill
rod support bearing 13 having a drilling machine side 17 and a
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drill bit side 18 opposite thereto; the drill bit holder 12 having a
drill bit holder axis 19 and being configured to hold a drill bit
aligned with the drill bit holder axis 19; a positioner arm 11
coupled, at a first end 21 thereof, to the drill bit holder 12; a
longitudinal movement mechanism 22 having a longitudinal
movement axis 23 oriented alongside the feed beam 4 in parallel
to the longitudinal axis 16; the longitudinal movement
mechanism 22 being coupled to a second end 24 of the
positioner arm 11 distally of the first end 21 thereof; the
longitudinal movement mechanism 22 being configured to move
the drill bit holder 12 by the positioner arm 11 between a
retracted longitudinal position 25, in which the drill bit holder 12
is at least partly longitudinally retracted behind the drill bit side
18 in a direction from the front end 10 towards the rear end 15,
and a protruded longitudinal position 26, in which the drill bit
holder 12 protrudes longitudinally in its entirety in front of the
drill bit side 18 in a direction from the rear end 15 towards the
front end 10; a transverse movement mechanism 27 coupled to
the positioner arm 11 and being configured to move the drill bit
holder 12 transversally to the longitudinal axis 16 between the
drill bit feeder position, in which the drill bit holder 12 is
configured to interact with a drill bit feeder 8, and a drill rod
position, in which the drill bit holder 12 is configured to align
longitudinally with the drill rod support bearing 13.
The longitudinal movement mechanism 22 and the transverse
movement mechanism 27 are integrated in a single drill bit
holder movement mechanism 28, which is made of a fixedly
mounted inner metal tube 29 inside a slidable outer metal tube
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30 operated for longitudinal movement by a hydraulic cylinder.
The outer metal tube 30 carries at one end the positioner arm
11, which extends underneath the feed beam 4 to the opposite
side where it carries drill bit holder 12 located in the drill bit
feeder position when the drill bit change positioner is retracted.
The outer metal tube 30 has an elongated guiding slot 31 that
interacts with a guiding pin 32, which is fixed in relation to the
beam 4. A mechanism is arranged for causing the outer metal
tube to slide longitudinally while also rotating as caused by the
interaction between the guiding slot 31 and the guiding pin 32.
Thus, the positioner arm 11 moves the drill bit holder 12
between the drill bit feeder position and a drill rod position.
Thus, the transverse movement mechanism 27 provides the
transverse movement of the drill bit holder 12 around a
rotational movement axis aligned the longitudinal movement
axis. As explained, the longitudinal movement axis 23 and the
drill bit feeder position 7 are located at opposing sides of the
feed beam 4.
Figs. 7 ¨ 9 show the drill bit feeder 8 mounted on a feed beam 4
configured to be part of a drill rig 1 for rock drilling, said drill bit
feeder 8 mounted on the feed beam 4 comprising: the feed
beam 4 having a drill rod support bearing 13 at a front end 10
configured to be turned towards a rock to be drilled, a drilling
machine 14 at a rear end 15 opposite to the front end 10 and a
longitudinal axis 16 extending between the front end 10 and the
rear end 15; the drill rod support bearing 13 having a drilling
machine side 17 and a drill bit side 18 opposite thereto; a drill
bit gripper 33 configured to grip and release on one side of the
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feed beam 4 a drill bit in a drill bit holder 12 of a drill bit change
positioner 7, in locations longitudinally behind the drill bit side
18 in a direction from the front end 10 towards the rear end 15.
In particular, figs. 8a and 8b show details of the drill bit feeder
8. It is further provided with a piston rod 34 having at a first end
thereof a central passage 35 for hydraulic fluid, an outlet 36 for
hydraulic fluid, a hydraulic piston 37 attached to the piston rod
34, an expansion chamber 38, all cooperating to pull or release
the piston rod 34. The piston rod 34 has at a second end thereof
an expander head 39 with two beveled jaws 40a and 40b, the
relative positions of which are variable by means of pulling or
releasing the piston rod 34, expander elements 41a and 41b
positioned between the jaws 40a and 40b, being beveled to
match the jaws 40a and 40b, and held together flexibly by two
rubber 0-rings 42a and 42b. When the piston rod 34 is released,
the jaws and the expander elements 41a and 41b form an
essentially smooth cylinder shape (fig 8b) that will make the
expander head 39 fit inside inner threads of a drill bit. When the
piston rod 34 is pulled, the expander elements will assume an
expanded configuration (fig 8a) that will make the expander
head 29 tightly grip inner threads of a drill bit. The piston rod 34
exits the expansion chamber 38 through a seal 43 adjacent to
the expander head 39. The expansion chamber 38 is formed by
a hydraulic cylinder 44 having a lid 45 at an end opposite to that
of the seal 43. The drill bit gripper 33 is formed generally by the
jaws, the expander elements and the 0-rings.
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The drill bit feeder 8 comprises the drill bit change positioner 7,
wherein the drill bit feeder position is on said one side of the
feed beam 4 (left side of feed beam in related figures).
5 Figs. 7 and 9 further show the drill bit magazine mounted on a
feed beam 4 configured to be part of a drill rig 1 for rock drilling,
said drill bit magazine 9 mounted on the feed beam 4
comprising: the feed beam 4 having a drill rod support bearing
13 at a front end 10 configured to be turned towards a rock to be
10 drilled, a drilling machine at a rear end 15 opposite to the front
end 10 and a longitudinal axis 16 extending between the front
end 10 and the rear end 15; the drill rod support bearing 13
having a drilling machine side 17 and a drill bit side 18 opposite
thereto; the drill bit magazine 9 being configured to hold a
15 plurality of new drill bits 46a and 46b (one or two shown in fig.
9) in receiving positions 47a ¨ 47c (advantageously seven or
more in total) inside the drill bit magazine 9 and to feed on one
side of the feed beam 4 a drill bit 46a to a drill bit holder 12 of a
drill bit change positioner 7 via locations longitudinally behind
the drill bit side 18 in a direction from the front end 10 towards
the rear end 15; the drill bit magazine being configured to hold
the plurality of drill bits 46a and 46b parallel to the longitudinal
axis 16; the drill bit magazine 9 being configured to convey the
plurality of drill bits 46a and 46b towards a drill bit feeder
position.
The drill bit magazine 9 comprises: a carrier mechanism 48
including a chain loop 49 with carrier pins 50 to move the new
drill bits 46a and 46b, said carrier mechanism 48 being
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configured to move the plurality of drill bits 46a and 46b parallel
to the longitudinal axis16 and eventually down onto a magazine
shelf 51 reachable by the drill bit feeder 8, which is to grip a drill
bit located on the magazine shelf 51 as described herein.
The drill bit magazine 9 interacts with the drill bit change
positioner 7 and the drill bit holder 12 thereof.
Figs. 1 ¨ 9 thus illustrate a rock-drilling drill rig 1 and
components thereof. The drill rig carries, on at least one drill
boom thereof, the feed beam 4 and at least one of the following
components: the drill bit change positioner 7; the drill bit feeder
8; the drill bit magazine 9.
Figs. 2 ¨ 9 show the drill bit changer 6 mounted on a feed beam
4 configured to be part of a drill rig 1 for rock-drilling, said drill
bit changer 6 mounted on the feed beam 4 comprising: a drill bit
change positioner 7 movably mounted on the feed beam 4; a
drill bit feeder 8 mounted on the feed beam 4.
Figs. 2 ¨ 9 further show the drill bit changer 6, comprising a drill
bit magazine 9 mounted on a feed beam 4.
Figs. 9a ¨ 9i show details of a combination of the drill bit feeder
8 and the drill bit magazine 9, both mounted alongside and
closely onto the feed beam 4, with their main longitudinal
dimension parallel to the longitudinal axis 16. The drill bit
magazine 9 has an loading opening 52 (depicted in fig. 7),
through which new drill bits 46a and 46b are to be introduced by
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an operator, either one by one or, possibly, via a cartridge (not
shown) holding several new drill bits. The drill bit magazine 9 is
designed as a generally cylindrical enclosure 53 (including the
loading opening 52) for an intended drill bit size, such as 50 mm
in greatest outer diameter. The cylindrical enclosure 53 has at
the bottom thereof the chain loop 49, horizontally (when feed
beam 4 is in level, as is generally assumed in this description)
looped around chain sprockets 54a and 54b, one of which is
coupled to a step motor 55. The chain loop 49 has the carrier
pins 50 mounted vertically thereon (at a distance from each
other greater than a maximum length of the intended drill bits) to
move the new drill bits towards a transfer opening 56 to make a
new drill bit land (advantageously via a top of the drill bit feeder
as an intermediate step to avoid risk of misplacement of the new
drill bit) on the magazine shelf 51. The drill bit magazine also
has an ejection opening 57 for ejecting used drill bits into a
container (not shown) to be located under the ejection opening
57.
The drill bit feeder 8 located below the new drill bits in the drill
bit magazine 9 is described above as to its composition. The
hydraulic cylinder 44, or an extension thereof, forms a drill bit
feeder shaft 58 operable to extend (parallel to the longitudinal
axis 16) in a direction of the drill bit holder 12 at a 1/4 extended
position, a 2/4 extended position, a 3/4 extended position, and
a 4/4 extended position. The drill bit feeder shaft 58 slides in a
feeder shaft guide 59 and has an actuator (not shown) to cause
it movements.
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Where possible and motivated, all components for drill bit
change disclosed herein, as well as the drill bits, are to be
protected in conventional ways from contamination by solids or
fluids in the environment or resulting from the drilling to be
performed. Conventional protection against vibration or physical
impact are also assumed included in the design as may be
required for robustness.
With further reference to a flow chart of fig. 10, the invention
can be expressed as a method for drill bit change in a rock-
drilling drill rig 1 carrying, on at least one drill boom 2 thereof, a
feed beam 4 and the drill bit change positioner 7 according to
the foregoing, said method comprising the following steps for
the drill bit change positioner 7 to remove and dispose of a used
drill bit:
- Retracting in step 1001 the drill rod 20 to make room for the
drill bit holder 12 in its protruded longitudinal position 26;
- Moving longitudinally and transversally in step 1002 the drill bit
holder 12 (when empty) from its retracted longitudinal position
25 to its protruded longitudinal position 26;
- Inserting in step 1003 the used drill bit into the drill bit holder
12 by advancing the drill rod to position the used drill bit in the
drill bit holder 12:
- Unscrewing and retracting in step 1004 the drill rod 20 from
the used drill bit, leaving it in the drill bit holder 12;
- Moving longitudinally and transversally in step 1005 the drill bit
holder 12 (now holding the used drill bit) from its protruded
longitudinal position 26 to its retracted longitudinal position 25.
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Once the drill bit holder 12 holds a used drill bit in its retracted
longitudinal position 25, it can interact with the drill bit feeder 8
to dispose of the used drill bit, as will be further described below
in relation to fig. 12.
With further reference to a flow chart of fig. 11, the invention
can be expressed as a method for drill bit change in a rock-
drilling drill rig 1 carrying, on at least one drill boom 2 thereof, a
feed beam 4 and the drill bit change positioner 7 according to
the foregoing, said method comprising the following steps for
the drill bit change positioner 7 to receive and move a new drill
bit to the drill rod 20 and releasing it to the drill rod 20:
- Receiving in step 1101 in the drill bit holder 12 a new drill bit
from the drill bit feeder 8 when the drill bit holder 12 is in its
retracted longitudinal position 25;
- Moving longitudinally and transversally in step 1102 the drill bit
holder 12 (when holding a received new drill bit) from its
retracted longitudinal position 25 to its protruded longitudinal
position 26, while ensuring that the drill rod 20 has made room
for the drill bit holder 12 in its protruded longitudinal position 26;
- Advancing the drill rod 20 in step 1103 and screwing it into the
new drill bit held by the drill bit holder 12;
- Retracting in step 1104 the drill rod 20 and the new drill bit
from the drill bit holder 7;
- Moving longitudinally and transversally in step 1105 the drill bit
holder 12 (now empty) from its protruded longitudinal position 26
to its retracted longitudinal position 25.
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The drill bit holder's 12 interaction with the drill bit feeder 8 will
be further described below.
As shown in figs. 9a ¨ 9i and with further reference to a flow
5 chart of fig. 12, the invention can be expressed as a method for
drill bit change in the rock-drilling drill rig 1 carrying, on said at
least one drill boom thereof, the feed beam and the drill bit
feeder 8 and the drill bit magazine 9 according to the foregoing,
said method comprising:
10 - As a starting point, loading at step 1201 (see also fig 9a) the
drill bit magazine 9 with new (or refurbished) drill bits, wherein
the drill bit feeder 8 is typically (but not necessarily) in the 3/4
extended position;
- The drill bit feeder 8 gripping from the drill bit holder 12 (in its
15 retracted longitudinal position 25) at step 1202 (see also fig 9b)
via its expander head 39 a used drill bit 60, in the 4/4 extended
position;
- The drill bit feeder 8 moving at step 1203 (see also fig 9c) via
its expander head 39 the used drill bit 60 to a position above the
20 ejection opening 57, in the 2/4 extended position;
- The drill bit feeder 8 withdrawing at step 1204 (see also fig 9d)
its expander head 39 from the used drill bit 60 for it to fall
through the ejection opening 57, in the 1/4 extended position;
- Moving at step 1205 (see also fig 9e) the drill bit feeder 8 to
receive the new drill bit 46a, in the 3/4 extended position;
- Receiving on top of the drill bit feeder shaft 58 at step 1206
(see also fig 9f) the new drill bit 46a, wherein the drill bit feeder
8 is typically (but not necessarily), in the 3/4 extended position;
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- The drill bit feeder 8 withdrawing at step 1207 (see also fig 9g)
to let the new drill bit 46a fall onto the drill bit magazine shelf
51, in the 2/4 extended position;
- The drill bit feeder 8 gripping from the drill bit magazine shelf
51 in the 3/4 extended position at step 1208 (see also fig 9h) via
its expander head 39 the new drill bit 46a and moving it into the
drill bit holder 12 (in its retracted longitudinal position 25), in the
4/4 extended position;
- The drill bit feeder 8 releasing the new drill bit 46a and
withdrawing at step 1209 (see also fig 9i) into the 3/4 extended
position;
The method steps described above in relation to the drill bit
feeder 8 and the drill bit magazine 9 can be divided into sub-
steps performed independently by the drill bit feeder 8 and the
drill bit magazine 9, respectively, as there is a functional
interface between the two, at which the drill bit magazine 9
releases and the drill bit feeder 8 receives each new drill bit.
DRAWING REFERENCES LIST
Face drill rig 1
Drill boom 2, 3
Feed beam 4, 5
Drill bit changer 6
Drill bit change positioner 7
Drill bit feeder 8
Drill bit magazine 9
Front end 10 of feed beam
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Positioner arm 11
Drill bit holder 12
Drill rod support bearing 13
Drilling machine 14
Rear end 15 of feed beam
Longitudinal axis 16 of feed beam
Drilling machine side 17 of drill rod support
Drill bit side 18 of drill rod support
Drill bit holder axis 19
Drill rod 20
First end 21 of positioner arm 11
Longitudinal movement mechanism 22
Longitudinal movement axis 23 of longitudinal movement
mechanism
Second end 24 of positioner arm 11
Retracted longitudinal position 25 of drill bit holder 12 (also
referred to as drill bit feeder position to denominate a
location of an interface, in which a drill bit is to be
transferred between the drill bit change positioner and the
drill bit feeder)
Protruded longitudinal position 26 of drill bit holder 12 (also
referred to as drill rod position to denominate a location of
an interface, in which a drill bit is to be transferred
between the drill bit change positioner and the drill rod)
Transverse movement mechanism 27 of drill bit change
positioner 7
Integrated single drill bit holder movement mechanism 28
Inner metal tube 29
Outer metal tube 30
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Elongated guiding slot 31
Guiding pin 32
Drill bit gripper 33
Piston rod 34
Central passage 35 of piston rod 34
Outlet 36 from piston rod for hydraulic fluid
Hydraulic piston 37
Expansion chamber 38
Expander head 39
Beveled jaws 40a and 40b opposite to each other
Expander elements 41a and 41b between beveled jaws
Rubber 0-rings 42a and 42b holding expander elements
Seal 43 of piston rod extension our of expansion chamber
Hydraulic cylinder 44 in which hydraulic piston travels
Lid 45 of hydraulic cylinder towards first end of piston rod
New drill bits 46a and 46b
Receiving positions 47a ¨ 47c for new drill bits in magazine
Carrier mechanism 48
Chain loop 49 of carrier mechanism
Carrier pins 50 of chain loop
Magazine shelf 51 (a generally enclosed space)
Loading opening 52 of magazine
Cylindrical enclosure 53
Chain sprockets 54a and 54b
Step motor 55
Transfer opening 56
Ejection opening 57
Drill bit feeder shaft 58
Drill bit feeder shaft guide 59
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Used drill bit 60
With "parallel" is herein meant substantially parallel.
With "alongside" is herein meant close beside something, or
extending in a line close beside something.
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