TECHNICAL FIELD
[0001] The present invention relates to booms for mining vehicle, and particularly to an
extendable boom.
BACKGROUND
[0002] In mines and other working sites, the mining apparatuses and vehicles are exposed
to harsh environmental conditions like falling objects. The operating cables, such
as electric, hydraulic, and data transfer cables, are routed outside the booms and
they are, thus, exposed to the environment. In applications where the boom is extendable,
the cables need to be long enough that they do not break when the boom is extended
to its extended position. Therefore, the cables hang loose when the extendable boom
is not in extended position and the loose cables may entangle itself. The external
cables are prone to break down and the repair and maintenance takes time. While the
apparatus is repaired, the apparatus is out of work, which costs. Further, cables
routed outside reduce visibility of the operator.
SUMMARY
[0003] The objective of the apparatus is to alleviate the disadvantages mentioned above.
[0004] In particular apparatus is to provide more efficient extendable boom having special
cable routing.
[0005] According to a first aspect, the present invention provides, it is an objective of
the present an extendable boom for a mining vehicle. The extendable boom comprises
an outer boom, an inner boom, having a distal end and a proximal end, arranged at
least partly inside the outer boom. The inner boom is arranged to extend in axial
direction out of the outer boom. Cables are provided for operating the device. The
inner boom comprises a rear pulley in proximity of the proximal end. The inner boom
comprises a front pulley mechanism, comprising a front pulley, at a distant from the
rear pulley towards the distal. The cables are routed within the inner boom and the
outer boom, wherein the cables are arranged to extend from the proximal end towards
the distal end, looped around the rear pulley towards the front pulley mechanism,
looped around the front pulley towards the distal end. An advantage of this is that
enclosing cables within boom structure reduces maintenance downtime, avoiding potential
for damage to exposed cables. Further, the risk for cables being impacted by falling
objects are significantly reduced. Also, the visibility of the operator is increased
as the cables are not routed outside of the boom structure.
[0006] In an embodiment of the device, the front pulley mechanism comprises a tensioner
device connected to the front pulley. An advantage of this is that the cables may
be tensioned inside the boom structure.
[0007] In an embodiment of the device, the tensioner device and the rear pulley are fixed,
and the front pulley is arranged to move between the tensioner device and the rear
pulley. An advantage of this is that inner boom may move in and out of the outer boom
with constant cable lengths.
[0008] In an embodiment of the device, the front pulley is tensioned by the tensioner device
towards the tensioner device. An advantage of this is that the front pulley may be
pretensioned.
[0009] In an embodiment of the device, the front pulley is arranged to move towards the
rear pulley and away from the tensioner device, when the inner boom is extended from
the outer boom. An advantage of this is that the front pulley may be tensioned towards
the tensioner device when the boom is extended.
[0010] In an embodiment of the device, the inner boom comprises at least one rod extending
from the proximal end towards the distal end, and the rear pulley and the front pulley
mechanism are connected to the telescopic tubes. An advantage of this is that the
mechanisms may be firmly connected to the inner boom parts without need of additional
connecting parts.
[0011] In an embodiment of the device, the rod is telescopic tube.
[0012] In an embodiment of the device, the rear pulley is fixed to the at least one rod,
and the front pulley is movable along the at least one rod. An advantage of this is
that present parts may be used for moving and guiding the moving front pulley.
[0013] In an embodiment of the device, the distal end is attached to a rotation unit.
[0014] In an embodiment of the device, the inner boom comprises a housing for protecting
inner parts from environmental conditions. An advantage of this is that extended inner
boom may be protected from environment.
[0015] In an embodiment of the device, the first end and the second end of the cables are
fixed outside of the inner boom. An advantage of this is that the cables length inside
the boom structure does not vary.
[0016] In an embodiment of the device, the tensioner device is a spring. An advantage of
this is that a spring is simple effective part for the purpose.
[0017] In an embodiment of the device, a hydraulic cylinder is provided within the boom
structure for reciprocating the inner boom. An advantage of this is that the extension
of the boom is enabled with components inside the boom structure.
[0018] In an embodiment of the device, the rear pulley and the front pulley mechanism are
connected to the hydraulic cylinder. An advantage of this is that there is no need
for separate components for fastening the pulleys.
[0019] According to another aspect, the invention provided a mining vehicle comprising an
extendable boom according to any of the above embodiments, wherein the distal end
of the inner boom is attached to a rotation unit comprising a working tool, and the
cables are routed inside the extendable boom to the rotation unit.
[0020] It is to be understood that the aspects and embodiments of the invention described
above may be used in any combination with each other. Several of the aspects and embodiments
may be combined together to form a further embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The accompanying drawings, which are included to provide a further understanding
of the invention and constitute a part of this specification, illustrate embodiments
of the invention and together with the description help to explain the principles
of the invention. In the drawings:
Fig. 1 shows an overview of an extendable boom in retracted position,
Fig. 2 shows an overview of an extendable boom in extended position,
Fig. 3 shows a detailed view of inner parts of the inner boom in retracted position,
Fig. 4 shows a detailed view of inner parts of the inner boom in extended position, and
Figs. 5 to 8 show embodiments of the inner parts of the inner boom comprising different fastening
means for a front pulley mechanism and a rear pulley.
DETAILED DESCRIPTION
[0022] Figures 1 and 2 show an overview of an extendable boom for a mining vehicle, such
as drilling rig used in mines or construction sites. In figure 1, the extendable boom
in a retracted position and in figure 2 the extendable boom is in an extended position.
The extendable boom 1 may be connected to a carrier of the mining vehicle from its
first end 2 and a rotation unit comprising a feed beam of a mining vehicle having
a working tool (e.g. rock drilling machine, reinforcement device, measurement device
or hydraulic breaker) may be fastened to the second end 3. Alternatively, the working
tool may be connected directly to the second end 3.
[0023] The extendable boom 1 comprises an outer boom 4 and inner boom 5, which may be connected
to a rotation unit. The outer boom 4 forms a housing for the extendable boom 1 and
the inner boom 5 is arranged at least partly inside the outer boom 4. The extension
of the boom 1 is achieved by moving the inner boom 5 in axial direction out of the
outer boom 4. The inner boom 5 has a retracted position, in which the inner boom 5
is in retracted inside the outer boom 4, i.e. the extendable boom 1 is in its shortest
length, and an extended position, in which the inner boom 5 is extended out of the
outer boom 4, i.e. the extendable boom 1 is in its greatest length.
[0024] Figure 3 shows a detailed view of the inner parts 6 of the inner boom 5 in the retracted
position and figure 4 shows a detailed view of the inner parts 6 of the inner boom
5 in the extended position. The inner boom 5 has two ends, a proximal end 7 and a
distal end 8. The proximal end 7 is closer to the first end of the extendable boom
1 and the distal end 8 is the opposite end that is closer to the second end of the
extendable boom 1.
[0025] The inner boom 5 comprises a rear pulley 9, which is provided in proximity of the
proximal end 7 and a front pulley mechanism 10, which is provided at a distant from
the rear pulley 9 towards the distal end 8. The front pulley mechanism 10 comprises
a front pulley 11. The pulley mechanisms are provided for routing cables 12 running
inside the extendable boom 1 and within the inner boom 5 and outer boom 4. The cables
may include electric cables and/or data transmission cables, such as CAN-cable to
feed the boom, drive motor, sensor, brake power and/or encoder cables etc. The cables
12 are extending from the distal end of the inner boom 5 towards the proximal end
7, looped around the rear pulley 9 (i.e. turn 180°) towards the front pulley mechanism
10, looped around the front pulley 11 (i.e. turn 180°) towards the proximal end 7.
[0026] The front pulley mechanism 10 may comprise a tensioner device 13 which is connected
to the front pulley 11. The tensioner device 13 may be for example a spring (e.g.
constant force spring or other linear or nonlinear force spring), a cylinder or a
winch, which is arranged to form tension between the front pulley 11 and the tensioner
device 13, i.e. pulling the front pulley towards the tensioner device. The tensioner
device 13 may also be for example a rubber element or a spring, which may be made
of rubber.
[0027] The rear pulley 13 and the tensioner device 13 may be fixed, e.g. to the inner boom
5, while the front pulley 11 is arranged to move between the tensioner device 13 and
the rear pulley 13. Thus, when the cables are fixed at both ends, the front pulley
11 may move towards the rear pulley 13, and away from the tensioner device 13, when
the inner boom 5 is extending out of the outer boom 4 to its extended position, i.e.
the extendable boom 1 is growing its length. The tensioner device 13 forms a tension
between the front pulley 11 and the tensioner device 13, when the inner boom 5 is
extending. When the inner boom 5 is retracting towards its retracted position, the
tension formed between the tensioner device 13 and the front pulley 11 moves the front
pulley towards the tensioner device 13. The front pulley 11 may be pretensioned towards
the tensioner device, when the inner boom 5 is in retracted position. The tensioner
device 13 and the front pulley 11 may be connected by a wire or wires, such as steel
wires, to carry the pretension and retraction force. The front pulley 11 may be arranged
to move half of the extended length of the inner boom 5. For example, when the inner
boom 5 is extended 1200 mm, the front pulley 11 will move 600 mm towards the rear
pulley 13. The inner boom 5 may comprise a hydraulic cylinder 15 for enabling the
movement of the inner cylinder between the extended position and retracted position.
A fixed clevis 16, or such, may be arranged at the end of the hydraulic cylinder 15
for fastening the hydraulic cylinder 15 to first end of the outer boom.
[0028] The inner boom 5 may comprise at least one rod extending from the proximal end 7
towards the distal end 8. The inner boom 5 may comprise several rods and the disclosure
apply also to the structure where several rods are used. In such structure, the definitions
should be understood to applied to rods. Different embodiments of the rod or rods
are shown in figures 5 to 8.
[0029] The rod provides linear guide and anchor points for the cable routing components,
such as the front pulley mechanism 10 and the rear pulley 9, which may be connected
to the rod as shown in figures 5 to 8. The rear pulley 9 and the tensioner device
13 may be fixed to the rod, for example by clamping. The front pulley 11 may be arranged
to be movable, e.g. slide, along the rod. The rear pulley 9, front pulley 11 and the
tensioner device 13 may be engaged with two parallel rods so that each component comprises
two clamping mechanism arranged on opposite sides of each pulley or tensioner device,
to engage with parallel rods. The rear pulley 9 may be engaged with different rods
than the front pulley 11 and the tensioner device 13.
[0030] The rod may be extended through the proximal end of the inner boom 5 inside the outer
boom 4 and/or the rod may extend through the distal end of the inner boom 5. Thus,
it may be used for guiding and moving the inner boom 5 between the extended position
and retracted position.
[0031] Figures 5 to 8 show different kind of structures of inner parts 6 and how the rear
pulley 9 and the front pulley mechanism 10 may be implemented inside the inner boom
5.
[0032] In figure 5, the inner boom 6 comprises several rods, which are service lines 14
of the device. The service lines 14 are used for providing fluids, such as hydraulic
fluid, to the working tool and they are extending through the proximal end 7 and the
distal end 8. The front pulley mechanism 10 and the rear pulley 9 are connected to
the service lines 14. The tubes may be telescopic tubes, which extend when the inner
boom 6 is extended.
[0033] In figure 6, the hydraulic cylinder 15 serves as the rod and the rear pulley 9 and
the front pulley mechanism 10 are connected to the hydraulic cylinder 15.
[0034] In figure 7, the hydraulic cylinder comprises dove tail guides 17. The dove tail
guide 17 may be fastened to a cylinder profile and providing even surfaces for the
sliding front pulley 11, which enables better control of the movement.
[0035] In figure 8, the inner boom 6 comprises several rods 18 which are connected to the
proximal end 7 and the distal end 8 of the inner boom so that they do not extend through
the ends, i.e. the rods are suspended to the end plates.
[0036] The inner boom 5 may comprise a housing for protecting the inner boom 5 components
when the inner boom 5 is extended out of the outer boom 4.
[0037] The distal end 8 of the inner boom 5 may be connected to a rotation unit, which allows
controlling and adjusting of the working tool in desired position.
[0038] The cables 12 may be fixed outside of the inner boom 5. For example, the first end
of the cables may be connected (and fixed) to the carrier of the mining vehicle, and
the other end to the working tool of the mining vehicle. Thus, the length of the cables
inside the extendable boom 1 is constant and the cable extension during the extension
of the boom 1 is achieved by the movable front pulley 11.
[0039] The extendable boom structure may be attached to a mining vehicle, such as a drilling
rig used in mines or construction sites. The first end of the boom may be connected
to a carrier of the mining vehicle and the distal end 8 of the inner boom 5 is attached
to a rotation unit comprising a feed beam of a mining vehicle having a working tool
(e.g. rock drilling machine, reinforcement device, measurement device or hydraulic
breaker). Alternatively, the working tool may be connected directly to the second
end 3. The cables 12 may be routed inside the extendable boom 1 from the carrier of
the mining vehicle to the working tool. As the cables are routed inside the boom structure,
they are protected from the environment, e.g. falling rocks. Further, they do not
hang loose in any situation, which could cause them break when hit to some objects.
[0040] Although the invention has been the described in conjunction with a certain type
of device, it should be understood that the invention is not limited to any certain
type of device. While the present inventions have been described in connection with
a number of exemplary embodiments, and implementations, the present inventions are
not so limited, but rather cover various modifications, and equivalent arrangements,
which fall within the purview of prospective claims.
1. An extendable boom (1) for a mining vehicle, comprising
- an outer boom (4),
- an inner boom (5), having a distal end (8) and a proximal end (7), arranged at least
partly inside the outer boom (4), wherein the inner boom (5) is arranged to extend
in axial direction out of the outer boom (4),
- cables (12) for operating the device,
characterized in that
- the inner boom (5) comprises a rear pulley (9) in proximity of the proximal end
(7),
- the inner boom (5) comprises a front pulley mechanism (10), comprising a front pulley
(11), at a distant from the rear pulley (13) towards the distal end (8),
- the cables (12) are routed within the inner boom (5) and the outer boom (4), wherein
the cables (12) are arranged to extend from the distal end (8) towards the proximal
end (7), looped around the rear pulley (9) towards the front pulley mechanism (10),
looped around the front pulley (11) towards the proximal end.
2. The extendable boom (1) according to claim 1, wherein the front pulley mechanism (10)
comprises a tensioner device (13) connected to the front pulley (11) .
3. The extendable boom (1) according to claim 1 or 2, wherein the tensioner device (13)
and the rear pulley (9) are fixed, and the front pulley (11) is arranged to move between
the tensioner device (13) and the rear pulley (9).
4. The extendable boom (1) according to claim 2 or 3, wherein the front pulley (11) is
tensioned by the tensioner device (13) towards the tensioner device (13).
5. The extendable boom (1) according to any one of claims 2 to 4, wherein the front pulley
(11) is arranged to move towards the rear pulley (9) and away from the tensioner device
(13), when the inner boom (5) is extended from the outer boom (4).
6. The extendable boom (1) according to any one of the preceding claims, wherein the
inner boom (5) comprises at least one rod extending from the proximal end (7) towards
the distal end (8), and the rear pulley (9) and the front pulley mechanism (10) are
connected to the rod.
7. The extendable boom (1) according claim 6, wherein the rod is telescopic tube.
8. The extendable boom (1) according to claim 6 or 7, wherein the rear pulley (9) is
fixed to the at least one rod, and the front pulley (11) is movable along the at least
one rod.
9. The extendable boom (1) according to any one of the preceding claims, wherein the
distal end (8) is attached to a rotation unit.
10. The extendable boom (1) according to any one of the preceding claims, wherein the
inner boom (5) comprises a housing for protecting inner parts (6) from environmental
conditions.
11. The extendable boom (1) according to any one of the preceding claims, wherein the
first end (2) and the second end (3) of the cables (12) are fixed outside of the inner
boom (5).
12. The extendable boom (1) according to any one of the preceding claims, wherein the
tensioner device (13) is a spring.
13. The extendable boom (1) according to any one of the preceding claims, wherein a hydraulic
cylinder (15) is provided within the boom structure for reciprocating the inner boom
(5).
14. The extendable boom (1) according to any one of the preceding claims, wherein the
rear pulley (9) and the front pulley mechanism (10) are connected to the hydraulic
cylinder (15).
15. A mining vehicle comprising an extendable boom (1) according to any one of the preceding
claims,
characterized in that
- the distal end (8) of the inner boom (5) is attached to a rotation unit comprising
a working tool, and
- the cables (12) are routed inside the extendable boom (1) to the rotation unit.