Note: Descriptions are shown in the official language in which they were submitted.
LARGE-DIAMETER COMBINATION IMPACTOR AND DOWN-THE-HOLE
DRILLING RIG
[0001] This application claims the benefit of priority to the Chinese Patent
Application No.
202011320910.X, titled "LARGE-DIAMETER COMBINATORIAL HAMMER AND
DOWN-THE-HOLE DRILL RIG", filed on November 23, 2020 with the China National
Intellectual Property Administration, which is incorporated herein by
reference in its entirety.
FIELD
[0002] The present application relates to the field of mining equipment, in
particular to a large-
diameter combinatorial hammer, and the present application further relates to
a down-the-hole
drill rig.
BACKGROUND
[0003] Underground pipelines are an important part of urban infrastructure and
include
several major categories such as water supply, water drainage, fuel gas, heat,
electricity and
industrial pipelines. In consideration of protection of surface buildings and
requirements of
construction efficiency, horizontally directional drilling technology is
increasingly used in
laying of urban underground pipelines. The horizontally directional drilling
technology is a
technique in which drilling equipment at the surface is used to drill into
ground with a small
angle of incidence relative to the ground, to form a pilot hole, then the
diameter of the pilot hole
is reamed step by step to the required size and then pipelines are laid. There
are two main
categories of geological layers of construction for a horizontally directional
drill rig, namely
soft soil strata and complex strata.
[0004] For non-excavation pipeline laying construction of the horizontally
directional drill rig
in the soft ground condition, due to the lower hardness of the ground and the
long-time
development, the current construction equipment for guide and reaming is
developed more
thoroughly. A guide hole may generally be formed by using a deflecting drill
bit. For reaming
construction, there are currently wing-shaped, spiral-shaped and recessed-
shaped bits, which
are complete in type and highly efficient in construction. By using bits with
different diameters
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to ream the hole step by step, the reaming requirements for large-diameter
pipelines in the soft
soil ground can be satisfied.
[0005] For non-excavation pipeline laying construction of the horizontally
directional drill rig
for complex stratum such as rock ground and gravel ground, due to the great
technical
difficulties, less research is carried on, and lots of problems occur in the
construction.
[0006] With continuously developing economy, rapidly growing population and
the on-going
acceleration of urbanization process, the diameters of the underground
pipelines are required to
be larger and larger, and the demand for a large-diameter reaming device is
becoming more and
more urgent. However, increasing the diameter of reaming lines in the complex
ground such as
rock ground and gravel ground by increasing the diameter of pneumatic reaming
hammer has
the following deficiencies.
[0007] The rock drilling capacity of the hammer mainly depends on the impact
force of the
hammer on a rock surface. The impact force comes from the compressed air. In
order to reduce
the loss of the compressed air, generally, the distance between the drill pipe
and the hammer
unit is short. However, due to the large outer diameter (500 mm to 3000 mm) of
the hammer,
the axial length is relatively short, the axial length is relatively short,
poor perpendicularity in
hole formation may easily occur especially during drilling in ravelly ground.
SUMMARY
[0008] In order to solve the above technical problems, a large-diameter
combinatorial hammer
is provided according to the present application, in which the overall axial
length is increased,
resulting in good perpendicularity in hole formation during drilling in
ravelly ground. A down-
the-hole drill rig to which the above large-diameter combinatorial hammer is
applied is further
provided according to the present application, which also has the above
advantageous effects.
[0009] The technical solutions according to the present application are as
follows.
[0010] A large-diameter combinatorial hammer, including:
a base,
a first joint configured to be connected to a drill pipe;
a first fixing plate sleeved onto the first joint;
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a first barrel body detachably connected to the first fixing plate;
a second barrel body connected to the first barrel body, where a second fixing
plate is
provided on the second barrel body; and
a reinforcing assembly connected to the first fixing plate and the second
fixing plate
respectively, where the reinforcing assembly is connected to the first joint;
where at least two hammer units are provided in the second barrel body, a
fixing plate
assembly is provided between the base and the second fixing plate, and the
hammer units are
each configured to pass through the fixing plate assembly.
[0011] Preferably, the large-diameter combinatorial hammer further includes a
first fixing
assembly, where the hammer units are connected to the second fixing plate
through the first
fixing assembly.
[0012] Preferably, the first fixing assembly includes a first connection
member and a clamping
seat; where
each of the hammer units includes a second joint, the second joint is
connected to the
clamping seat in a clamping manner, a first pressing member is provided at one
end of the first
connection member, and the first pressing member is arranged above the second
fixing plate;
and
the first connection member passes through the second fixing plate and the
clamping seat
to be in threaded connection with the second joint.
[0013] Preferably, the large-diameter combinatorial hammer further includes a
draw rod
assembly, where one end of the draw rod assembly is connected to the base, and
the other end
of the draw rod assembly is connected to the second fixing plate.
[0014] Preferably, the draw rod assembly includes a draw rod passing through
the second
fixing plate, the fixing plate assembly and the base in sequence; and
a second pressing member in threaded connection with one end of the draw rod,
where a
bottom of the second pressing member abuts against the second fixing plate,
and the other end
of the draw rod is in threaded connection with the base.
[0015] Preferably, the reinforcing assembly has an upper joint portion
provided in a plumb
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direction and connected to the first fixing plate; and where
at least two first reinforcing ribs are provided on an outer wall of the upper
joint portion,
and the at least two first reinforcing ribs are connected to the first fixing
plate.
[0016] Preferably, the reinforcing assembly further includes a lower joint
portion having one
end connected to the upper joint portion and the other end connected to the
second fixing plate;
and
at least two second reinforcing ribs are provided on an outer wall of the
lower joint portion,
and the at least two second reinforcing ribs are connected to the second
fixing plate.
[0017] Preferably, a first air passage is provided in the first joint, a
second air passage is
provided in the reinforcing assembly, a first through-hole is provided in the
second fixing plate,
where the first air passage is in communication with the second air passage,
the first through-
hole and the hammer units in sequence.
[0018] Preferably, a third air passage is provided in the clamping seat, a
fourth air passage is
provided in the second joint, and the fourth air passage is in communication
with the first
through-hole through the third air passage.
[0019] A down-the-hole drill rig is provided, including the above large-
diameter
combinatorial hammer.
[0020] Compared with the conventional technology, with the large-diameter
combinatorial
hammer according to the present application, the first barrel body is provided
in addition to the
second barrel body, so that the axial length of the whole large-diameter
combinatorial hammer
is extended, to avoid rock slag falling into the hole before the hole is
formed, thereby ensuring
high perpendicularity in hole formation. On the other hand, the reinforcing
assembly is provided
inside the first barrel body, so that in the large-diameter combinatorial
hammer, not only the
second fixing plate is connected to the first barrel body, but also the first
fixing plate and the
second fixing plate are connected through the reinforcing assembly at a middle
portion inside
the first barrel body, so that the first barrel body and the second barrel
body can be connected
more securely. This arrangement avoids the shaking of the first fixing plate,
the first barrel body,
the second fixing plate and the second barrel body at the connection positions
due to the
unstable connection, thereby further ensuring high perpendicularity of hole
formation. Thirdly,
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during the drilling process of impacting the rock stratum, the rock stratum
exerts a reverse
impact force on the hammer units, with the arrangement of the fixing plate
assembly, middle
portions of the hammer units are fixed, thereby avoiding the problem of poor
perpendicularity
of hole formation due to playing of the hammer units. In summary, with the
large-diameter
combinatorial hammer according to the present application, the overall axial
length is increased,
and the high perpendicularity of hole formation is achieved in the process of
drilling in loose
rock stratum.
[0021] A down-the-hole drill rig, to which the above large-diameter
combinatorial hammer is
applied, is further provided according to the present application, which also
has the above
advantageous effects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] For more clearly illustrating technical solutions in embodiments of the
present
application or in the conventional technology, drawings used in the
description of the
embodiments or the conventional technology will be briefly described
hereinafter. Apparently,
the drawings in the following description illustrate only some embodiments of
the present
application, for those skilled in the art, other drawings may be obtained
based on the provided
drawings without any creative efforts.
[0023] FIG. 1 is a schematic view showing the internal structure of a large-
diameter
combinatorial hammer according to an embodiment of the present application;
[0024] FIG. 2 is a schematic view showing the structure of the large-diameter
combinatorial
hammer with a second barrel body being mounted according to the embodiment of
the present
application;
[0025] FIG. 3 is a schematic view showing the structure of a reinforcing
assembly according
to an embodiment of the present application;
[0026] FIG. 4 is an exploded view of the reinforcing assembly according to the
embodiment
of the present application;
[0027] FIG. 5 is an exploded view of a fixing plate assembly and a draw rod
assembly
according to an embodiment of the present application;
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[0028] FIG. 6 is a sectional view of the large-diameter combinatorial hammer
according to
the embodiment of the present application;
[0029] FIG. 7 is a sectional view of the large-diameter combinatorial hammer
according to
the embodiment of the present application;
[0030] FIG. 8 is a schematic view of a hammer unit according to an embodiment
of the present
application; and
[0031] FIG. 9 is a schematic view showing an external structure of an air
distribution structure
of the large-diameter combinatorial hammer according to an embodiment of the
present
application.
[0032] Reference numerals are as follows:
1 first joint, 2 first fixing plate,
3 first barrel body, 31 third slag discharge
groove,
4 second barrel body, 42 second slag discharge
groove,
5 second fixing plate, 500 first through-hole,
6 reinforcing assembly, 61 upper joint portion,
62 first reinforcing rib, 63 second reinforcing rib,
64 avoidance position, 65 second air passage,
66 lower joint portion, 7 hammer unit,
71 second joint, 711 fourth air passage,
712 first central hole, 72 check valve,
73 air distribution seat, 74 piston,
75 first air chamber, 76 second air chamber,
8 base, 81 first slag discharge
groove,
82 mounting seat, 9 drill bit,
91 air outlet hole, 92 first air discharge groove,
10 draw rod assembly, 100 first air passage,
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101 second pressing member, 11 first fixing assembly,
111 first connection member, 112 clamping seat,
113 first pressing member, 114 third barrel body,
1123 third air passage, 12 fixing plate assembly,
121 third fixing plate, 122 fourth fixing plate,
123 fifth fixing plate, 13 air chamber.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0033] For those skilled in the art to better understand the technical
solutions in the present
application, the technical solutions of the embodiments of the present
application will be
described clearly and completely hereinafter, in conjunction with the drawings
in the
embodiments of the present application. Apparently, the described embodiments
are only part
of the embodiments of the present application, rather than all the
embodiments. All the other
embodiments obtained by those skilled in the art based on the embodiments in
the present
application without any creative efforts fall into the scope of protection of
the present
application.
[0034] It should be noted that when an element is referred to be "fixed to" or
"provided on"
another element, the element may be directly on the another element or
indirectly on the another
element; when an element is referred to be "connected to" another element, the
element may be
directly connected to the other element or indirectly connected to the another
element.
[0035] It should be noted that the orientation or positional relationship
indicated by the terms,
such as "length", "width", "upper", "lower", "front", "rear", "first",
"second", "perpendicular",
"horizontal", "top", "bottom", "inner", and "outer", are based on the
orientation or positional
relationship shown in the drawings, which are only used to facilitate the
description of the
present application and to simplify the description, rather than indicating or
implying that the
device or element referred to must have a specific orientation, or can only be
configured and
operated in a particular orientation. Therefore the above terms should not be
construed as a
limitation to the present application.
[0036] Furthermore, the terms "first", "second" and the like are for purpose
of description,
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and should not be construed as indicating or implying relative importance or
implying the
number of the indicated technical features. Therefore, the features defined by
"first" and
"second" may explicitly or implicitly include one or more of the features. In
the description of
the present application, the meaning of "multiple" or "plurality of" is two or
more, unless
specifically defined otherwise.
[0037] The structure, proportion, and size shown in the drawings of the
specification are only
used for cooperation with the contents disclosed in the specification to
facilitate understanding
and reading for those skilled in the art, and are not intend to limit the
conditions under which
the present application can be implemented, therefor they have no technically
substantive
meaning. Any modification of structure, change of proportional relationship,
or adjustment of
size without affecting the effects and purpose of the present application
should still fall within
the scope of the technical content disclosed in the present application.
[0038] As shown in FIG. 1 to FIG. 9, a large-diameter combinatorial hammer
according to the
present application includes a base 8, a first joint 1 connected to a drill
pipe, a first fixing plate
2 sleeved onto the first joint 1, a first barrel body 3 detachably connected
to the first fixing plate
2, a second barrel body 4 connected to the first barrel body 3, a second
fixing plate 5 being
provided on the second barrel body 4, and a reinforcing assembly 6 connected
to the first fixing
plate 2 and the second fixing plate 5 respectively. The reinforcing assembly 6
is connected to
the first joint 1, at least two hammer units 7 are provided in the second
barrel body 4, a fixing
plate assembly 12 is provided between the base 8 and the second fixing plate
5, and the hammer
units 7 each passes through the fixing plate assembly 12.
[0039] Compared with the conventional technology, with the large-diameter
combinatorial
hammer according to the present application, the first barrel body 3 is
provided in addition to
the second barrel body 4, so that the axial length of the whole large-diameter
combinatorial
hammer is extended, to avoid rock slag falling into the hole before the hole
is formed, thereby
ensuring a high perpendicularity in hole formation. On the other hand, the
reinforcing assembly
6 is provided inside the first barrel body 3, so that in the large-diameter
combinatorial hammer,
not only the second fixing plate 5 is connected to the first barrel body 3,
but also the first fixing
plate 2 and the second fixing plate 5 are connected through the reinforcing
assembly 6 at a
middle portion inside the first barrel body 3, so that the first barrel body 3
and the second barrel
body 4 can be connected more securely. This arrangement avoids the shaking of
the first fixing
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plate 2, the first barrel body 3, the second fixing plate 5 and the second
barrel body 4 at the
connection positions due to the unstable connection, thereby further ensuring
high
perpendicularity of hole formation. Thirdly, during the drilling process of
impacting the rock
stratum, the rock stratum exerts a reverse impact force on the hammer units 7,
with the
arrangement of the fixing plate assembly 12, middle portions of the hammer
units 7 are fixed,
thereby avoiding the problem of poor perpendicularity of hole formation due to
playing of the
hammer units 7. In summary, with the large-diameter combinatorial hammer
according to the
present application, the overall axial length is increased, and the high
perpendicularity of hole
formation is achieved in the process of drilling in loose rock stratum.
[0040] As shown in FIG. 6, the large-diameter combinatorial hammer in the
embodiment of
the present application includes a first fixing assembly 11, through which the
hammer units 7
are connected to the second fixing plate 5. This arrangement enables the
hammer units 7 to be
more securely connected to the second fixing plate 5.
[0041] Further, the first fixing assembly 11 includes a first connection
member 111 and a
clamping seat 112, each of the hammer units includes a second joint 71, the
second joint 71 is
connected to the clamping seat 112 in a clamping manner, a first pressing
member 113 is
provided at one end of the first connection member 111, and the first pressing
member 113 is
arranged above the second fixing plate 5. The first connection member 111 is
in threaded
connection with the second joint 71 after passing through the second fixing
plate 5 and the
clamping seat 112. In this embodiment, the clamping seat 112 is connected to
the second joint
71 in a clamping manner, and the first connection member 111 is in threaded
connection with
the second joint 71 after passing through the second fixing plate 5 and the
clamping seat 112,
so that the clamping seat 112 does not play, thereby avoiding shifting at a
position where the
second joint 71 and the clamping seat 112 are connected. On the other hand,
the first pressing
member 113 is used to limit the position between the first connection member
111 and the
second fixing plate 5. Preferably, the first pressing member 113 is a nut.
Thus, according to this
embodiment, the connection between the hammer units 7 to the second fixing
plate 5 more
reliable, which prevents the hammer units 7 from falling off the second fixing
plate 5.
[0042] Preferably, as shown in FIG. 1 to FIG. 3, the fixing plate assembly 12
includes a third
fixing plate 121 and a fourth fixing plate 122 arranged in parallel with each
other, and both of
which are parallel to the second fixing plate 5. Each of the third fixing
plate 121 and the fourth
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fixing plate 122 is sleeved on outer walls of the hammer units. With the
arrangement of the
third fixing plate 121 and the fourth fixing plate 122 and their relative
positional relationship
with the second fixing plate 5, the hammer units 7 will not shake during
operation.
[0043] In an embodiment according to the present application, a draw rod
assembly 10 is
provided. One end of the draw rod assembly 10 is connected to the base 8, and
the other end of
the draw rod assembly 10 is connected to the second fixing plate 5. The one
end of the draw
rod assembly 10 being connected to the base 8 and the other end of the draw
rod assembly 10
being connected to the second fixing plate 5. With the effects of the draw rod
assembly 10, the
base 8 and the second fixing plate 5, one end of each of the hammer units 7 is
connected to the
second fixing plate 5 and a bottom of each of the hammer units 7 is movably
connected to the
base 8, which prevents the hammer units 7 from falling off the base 8 in a
condition that a drill
bit 9 performs reciprocating motion to impact the rock stratum.
[0044] The draw rod assembly 10 includes a draw rod passing through the second
fixing plate
5, the fixing plate assembly 12 and the base 8 in sequence, and a second
pressing member 101
in threaded connection with one end of the draw rod. A bottom of the second
pressing member
101 abuts against the second fixing plate 5, and the other end of the draw rod
is in threaded
connection with the base 8. Preferably, the number of the draw rod assembly 10
is at least two,
thus multiple tensioning forces are applied, so that the relative position
between the second
fixing plate 5 and the base 8 does not change, thereby the hammer units 7 have
more stable
structures and less likely to fall off.
[0045] Further, as shown in FIG. 3, the fixing plate assembly 12 includes a
fifth fixing plate
123, the fifth fixing plate 123 is provided below the fourth fixing plate 122
and is sleeved on
an outer wall of each of the hammer units. The number of fixing plates in the
fixing plate
assembly 12 may be adjusted according to the length of the hammer units 7, and
the fifth fixing
plate 123, the fourth fixing plate 122 and the third fixing plate 121 work
together so that the
hammer units 7 do not shake during operation.
[0046] In an embodiment according to the present application, as shown in FIG.
1 to FIG. 4,
the reinforcing assembly 6 has an upper joint portion 61 provided in a plumb
direction and
connected to the first fixing plate 2, and at least two first reinforcing ribs
62 are provided on an
outer wall of the upper joint portion 61, and the first reinforcing ribs 62
are connected to the
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first fixing plate 2. With the arrangement of the first reinforcing ribs 62,
the connection between
the upper joint portion 61 and the first fixing plate 2 is more secure.
[0047] The reinforcing assembly 6 includes a lower joint portion 66 having one
end connected
to the upper joint portion 61 and the other end connected to the second fixing
plate 5. At least
two second reinforcing ribs 63 are provided on an outer wall of the lower
joint portion 66, and
the second reinforcing ribs 63 are connected to the second fixing plate 5.
With the arrangement
of the second reinforcing ribs 63, the connection between the lower joint
portion 66 and the
second fixing plate 5 is more secure.
[0048] The first reinforcing ribs 62 and the second reinforcing ribs 63 are
arranged in a
staggered manner so that there are multiple reinforcing points on the first
fixing plate 2 and the
second fixing plate 5, and the reinforcing assembly 6 has multiple reinforcing
points in different
directions, making the reinforcing assembly 6 has better structure rigidity.
[0049] In another embodiment, at least one of the first reinforcing ribs 62 is
aligned with a
corresponding one of the second reinforcing ribs 63. In this way, the
reinforcing assembly 6 has
at least one reinforcing point where the reinforcing forces are in the same
direction, so that the
first reinforcing ribs 62 and the second reinforcing ribs 63 are connected
more securely.
[0050] An avoidance position 64 is provided on a side wall of the lower joint
portion 66.
Generally, in order to have a cutting edge at a position near a center of a
bottom of the large-
diameter combinatorial hammer, at least one hammer unit 7 is mounted near the
center of the
large-diameter combinatorial hammer, and the hammer unit 7 is mounted on the
second fixing
plate 5 through a connection member. To avoid interference with the connection
member, the
avoidance position 64 is provided on the side wall of the lower joint portion
66.
[0051] In an embodiment according to the present application, as shown in FIG.
6 to FIG. 9,
a first air passage 100 is provided in the first joint 1, a second air passage
65 is provided in the
reinforcing assembly 6, a first through-hole 500 is provided in the second
fixing plate 5, and
the first air passage 100 is in communication with the second air passage 65,
the first through-
hole 500 and the hammer units 7 in sequence. The first barrel body 3 is
provided in addition to
the second barrel body 4, so that the axial length of the whole large-diameter
combinatorial
hammer is extended, to avoid rock slag falling into the hole before the hole
is formed, thereby
ensuring high perpendicularity in hole formation. On the other hand, the
reinforcing assembly
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6 is provided inside the first barrel body 3, so that in the large-diameter
combinatorial hammer,
not only the second fixing plate 5 is connected to the first barrel body 3,
but also the first fixing
plate 2 and the second fixing plate 5 are connected through the reinforcing
assembly 6 at a
middle portion inside the first barrel body 3, so that the first barrel body 3
and the second barrel
body 4 can be connected more securely. In addition, the connection of the
reinforcing assembly
6 allows the compressed air to flow from the first air passage to the second
air passage 65, the
first through-hole 500, and directly into the hammer units 7, thus avoiding
the loss of the
compressed air in circulation. Therefore, with the air distribution structure
of the large-diameter
combinatorial hammer according to the present application, at the same time of
preventing
failure or fracture by ensuring good structural rigidity at the connection
between the drill pipe
and the hammer and the drill pipe and the hammer, the loss of compressed air
can be reduced
and the rock drilling capacity of the hammer can be improved.
[0052] An outer wall of the first joint 1 is slidingly connected to an inner
wall of the
reinforcing assembly 6 so that a bottom of the first joint 1 is placed within
the second air passage
65. In this way, the compressed air is allowed to flow directly into the
reinforcing assembly 6
from the first joint 1. Preferably, lubricating oil may be applied between the
outer wall of the
first joint 1 and the inner wall of the reinforcing assembly 6, to avoid the
compressed air
escaping from the reinforcing assembly 6, which reduces the loss of compressed
air, thereby
increasing the energy conversion efficiency of the large-diameter
combinatorial hammer and
increasing the rock drilling capacity.
[0053] A third air passage 1123 is provided in the clamping seat, and a fourth
air passage 711
is provided in the second joint 71. The fourth air passage 711 is in
communication with the first
through-hole 500 through the third air passage 1123.
[0054] In this embodiment, the clamping seat 112 is connected to the second
joint 71 in a
clamping manner, preferably, a bolt is employed to pass through the second
fixing plate 5 and
the clamping seat 112 to be in threaded connection with the second joint 71,
so that the clamping
seat 112 does not play, thereby avoiding shifting at a position where the
second joint 71 and the
clamping seat 112 are connected. On the other hand, while improving the
reliability of the
connection between the hammer units 7 and the second fixing plate 5 by using
the clamping
seat 112, the clamping seat 112 is provided with the third air passage 1123
and the second joint
71 is provided with the fourth air passage 711, and the fourth air passage 711
is in
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communication with the first through-hole 500 through the third air passage
1123. This
arrangement allows the high pressure air to enter the fourth air passage 711
from the clamping
seat 112, which reduces the loss of high pressure air, thereby increasing the
rock drilling
capacity.
[0055] Further, an air chamber 13 is defined by the third fixing plate 121,
the second fixing
plate 5 and the second barrel body 4, and the air chamber 13 is in
communication with the third
air passage 1123 and the first through-hole 500 respectively. Connection
between the first barrel
body 3, the first fixing plate 2, the second barrel body 4 and the second
fixing plate 5 may be
performed by welding, which avoid the high pressure air flowing out from the
gap, and thus the
air chamber 13 is highly airtight, which speeds up the flow of high pressure
air from the first
through-hole 500 to the third air passage 1123, thereby further reducing the
loss of high pressure
air and increasing the rock drilling capacity.
[0056] Each of the hammer units includes a check valve 72 fitted to a first
central hole 712 in
the second joint 71, an air distribution seat 73 abutting against the other
end of the check valve
72, a piston 74 fitted to the air distribution seat 73, a first air chamber 75
provided between the
piston 74 and the air distribution seat 73, and a second air chamber 76
provided between the
piston 74 and an end of a drill shank. A drill bit 9 is detachably connected
to one end of the
hammer unit, the drill bit 9 includes the drill shank. A reciprocating motion
of the piston 74 is
realized by changing air pressure in the first air chamber 75 and the second
air chamber 76,
which in turn impacts the drill bit 9, causing the drill bit 9 to impact the
rock stratum.
[0057] The high pressure air entering the hammer units to impact the rock
stratum is
implemented as follows. At the beginning, the check valve 72 is fitted to the
first central hole
712 of the second joint 71, the high pressure air enters the drill rig, passes
through the first air
passage 100, the second air passage 65, the first through-hole 500, the air
chamber 13 and then
is distributed to each of the hammer units, the high pressure air enters into
the hammer unit
from the third air passage 1123 and the fourth air passage 711, acts on the
check valve 72 and
applies a pressure on the check valve 72. The check valve 72 moves downwards,
so that the
check valve 72 is no longer fitted to the first central hole 712. Since one
end of the check valve
72 abuts against the air distribution seat 73, when the high pressure air
reaches the second air
chamber 76, the air pressure in the second air chamber 76 is greater than the
air pressure in the
first air chamber 75, thus the piston 74 is pushed to move upwards. When the
piston 74 moves
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to a position where the piston 74 is fitted to the air distribution seat 73,
the air pressure in the
first air chamber 75 rises, at which time the air pressure in the first air
chamber 75 is greater
than the air pressure in the second air chamber 76, and the air pressure in
the first air chamber
75 pushes the piston 74 to impact downwards, the end of the piston 74 applies
an impact force
to an end of the drill bit 9, to drive the drill bit 9 to impact downwards.
[0058] The piston 74 and the drill bit 9 each is provided with an air outlet
hole 91, and a lower
end of the drill bit 9 is provided with a first air discharge groove 92, which
is connected to the
air outlet hole 91. In order to speed up the removal of crushed rock slag to
avoid the
accumulation of crushed rock slag near the drill bit 9, the high pressure air
enters through the
first central hole 712, bursts the check valve 72 open, and enters the air
passage in the air
distribution seat 73, flows into the first air chamber 75, then enters the air
outlet hole in the
piston 74 and the air outlet hole 91 in the drill bit 9, and finally enters
the first air discharge
groove 92. Since the first air discharge groove 92 is arranged at the lower
end of the drill bit 9,
the space between the lower end of the drill bit 9 and the bottom of the rock
stratum is limited,
and the high pressure air has a certain pressure and speed, thus the high
pressure air forms a
cyclone between the lower end of the drill bit 9 and the bottom of the rock
stratum. The cyclone
makes the crushed rock slag to be discharged around the drill bit 9, which
greatly accelerates
the speed of slag discharge and thereby avoiding overheating of the drill bit
9.
[0059] Further, the base 8 is provided with a first slag discharge groove 81,
and the first slag
discharge groove 81 is in communication with the first air discharge groove
92; the second
barrel body 4 is provided with a second slag discharge groove 42, and the
second slag discharge
groove 42 is in communication with the first slag discharge groove 81; and the
first barrel body
3 is provided with a third slag discharge groove 31, the third slag discharge
groove 31 is in
communication with the second slag discharge groove 42. In this way, the
crushed rock slag
flows from the first air discharge groove 92 to the first slag discharge
groove 81, the second
slag discharge groove 42, and the third slag discharge groove 31, which
enables the large-
diameter combinatorial hammer to discharge the rock slag in time while
drilling, avoiding
excessive friction between the rock slag and the first barrel body 3, the
second barrel body 4
and the base, thereby improving the service life.
[0060] Since the drill bit 9 performs up and down reciprocating motion, and
the base 8 is
sleeved on the outer wall of the drill bit 9, the base 8 is severely worn
after a long period of use,
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which increases the gap between the drill bit 9 and the base 8 through which
the crushed rock
slag may be blown into the second barrel body 4, causing the crushed rock slag
to enter the air
chamber 13, and finally the crushed rock slag enters the piston 74 inside the
hammer unit. Once
the crushed rock enters the first air chamber 75 and the second air chamber
76, the piston 74
will get stuck and cannot work. Therefore, a mounting seat 82 is provided in
the present
application, the mounting seat 82 is sleeved onto the outer wall of the drill
bit 9, and then the
mounting seat 82 is tightly fitted to the base 8. When the mounting seat 82 is
damaged, it can
be replaced without replacing the entire base 8, which reduces the maintenance
cost of the large-
diameter combinatorial hammer while ensuring the service performance of the
large-diameter
combinatorial hammer.
[0061] It should be noted that the following improvements are made to reduce
manufacturing
costs. With regard to the formation of the third slag discharge groove 31 on
the first barrel body
3 and the second slag discharge groove 42 on the second barrel body 4, a slice
of the third slag
discharge groove 31 and a slice of the second slag discharge groove 42 are cut
out of the first
barrel body 3 and the second barrel body 4, respectively, and the slices are
turned 1800 so that
both the opening of the third slag discharge groove 31 and the opening of the
second slag
discharge groove 42 face outward, and after the parts inside the large-
diameter combinatorial
hammer are assembled, welding is performed. In this way, the material of the
barrel body itself
can be used, which reduces the processing costs of the third slag discharge
groove 31 and the
second slag discharge groove 42, thereby reducing the manufacturing costs of
the large-
diameter combinatorial hammer.
[0062] A down-the-hole drill rig is provided according to the present
application. The down-
the-hole drill rig includes the above large-diameter combinatorial hammer, and
also has the
above effects, which will not be repeated here.
[0063] According to the above description of the disclosed embodiments, those
skilled in the
art can implement or practice the present application. Various modifications
to the embodiments
are apparent for those skilled in the art. The general principle defined
herein may be
implemented in other embodiments without departing from the spirit or scope of
the present
application. Therefore, the present application will not be limited to the
embodiments described
herein, but should be in accordance with the broadest scope consistent with
the principle and
novel features disclosed herein.
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